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Pancreatic cancer is one of the most aggressive cancers worldwide with a high mortality rate. Prognosis remains poor even in this era of advanced medicine mainly due to early metastasis and invasion. The present study aimed to explore and validate predictors of distant metastasis and prognosis in pancreatic cancer. In our preliminary experiment, we established a novel metastatic pancreatic cancer cell line BxPC-M8 from parent BxPC-3 cells. Via whole genome sequencing, RT-qPCR, western blotting, migration and invasion assays, we initially found that BxPC-M8 shared similar biological characteristics to BxPC-3, but only differed in enhanced metastatic and invasive capabilities with a significant increase in collagen type VI α1 chain (COL6A1) expression. Knockdown of COL6A1 via small interfering RNA led to a significant decrease in migration and invasion of BxPC-M8 cells, suggesting suppressed epithelial-mesenchymal transition. Furthermore, a significant increase in COL6A1 expression was observed in cancerous tissue compared with paracancerous tissue (40.7 vs 3.7, P=0.001). Additionally, its expression was observed to be significantly associated with distant metastasis and vascular invasion at the time of surgery. Multivariate analysis revealed that COL6A1 expression (hazard ratio 1.90, 95% confidence interval 1.04-3.47, P=0.037) is an independent predictor of overall survival (OS). The median OS observed for COL6A1+ and COL6A1− patients was found to be 8±4 and 14±7 months (P=0.021), respectively. Of note, we identified that COL6A1 expression in tissue samples was associated with significantly reduced OS (P=0.001), demonstrating that COL6A1 may serve an important role in the metastatic process and could be considered as a predictor of poor outcomes in patients with pancreatic cancer. In addition, our findings suggest that COL6A1 could be an indicator of distant metastasis and a valid prognostic predictor in such patients; however, further investigation is required.

Carboxyl ester lipase (CEL) encodes a cholesterol ester hydrolase that is secreted into the duodenum as a component of pancreatic juice. The objective of this study was to characterize the CEL gene, investigate the association between the CEL promoter variants and chicken phenotypic traits, and explore the CEL gene regulatory mechanism. An insertion/deletion (indel) caused by a 99-bp insertion fragment was shown for the first time in the chicken CEL promoter, and large differences in allelic frequency were found among commercial breeds, indigenous and feral birds. Association analysis demonstrated that this indel site had significant effects on shank length, shank girth, chest breadth at 8 weeks (p p CEL gene in pancreatic tissue. Moreover, the expression levels of the genes APOB, MTTP, APOV1 and SREBF1, which are involved in lipid transport, were significantly reduced by adding a 4% oxidized soybean oil diet treatment at the individual level and transfecting the embryonic primary hepatocytes with a CEL-overexpression vector. Interestingly, the results showed that the expression level of the II homozygous genotype was significantly higher than that of the ID and DD genotypes, while individuals with DD genotypes had higher phenotypic values. Therefore, these data suggested that the CEL gene might affect body growth by participating in hepatic lipoprotein metabolism and that the 99-bp indel polymorphism could be a potentially useful genetic marker for improving the economically important traits of chickens.

Recent decades have seen increasingly restrictive regulations applied to gasoline engines. Gasoline combustion chemistry must be investigated to achieve a better understanding and control of internal combustion engine efficiency and emissions. In this work, several gasoline fuels, namely the FACE (Fuel for Advanced Combustion Engines) gasolines, were selected as targets for oxidation study in jet-stirred reactors (JSR). The study is facilitated by formulating various gasoline surrogate mixtures with known hydrocarbon compositions to represent the real gasolines. Surrogates included binary mixtures of n-heptane and iso-octane, as well as more complex multi-component mixtures. The oxidation characteristics of FACE gasolines and their surrogates were experimentally examined in JSR-1 and numerically simulated under the following conditions: pressure 1 bar, temperature 500–1050 K, residence time 1.0 and 2.0 s, and two equivalence ratios (ϕ = 0.5 and 1.0). In the high temperature region, all real fuels and surrogates showed similar oxidation behavior, but in the low temperature region, a fuel’s octane number and composition had a significant effect on its JSR oxidation characteristics. Low octane number fuels displayed more low temperature reactivity, while fuels with similar octane number but a larger number of n-alkane components were more reactive. A gasoline surrogate kinetic model was examined with FACE gasoline experiments either measured in JSR-2, or taken from previous work under the following conditions: pressure 10 bar, temperature 530–1200 K, residence time 0.7 s, and three equivalence ratios (ϕ = 0.5, 1.0 and 2.0). Comparison between FACE gasoline experimental results with surrogate model predictions showed good agreement, demonstrating considerable potential for surrogate fuel kinetic modeling in engine simulations.

Ketohydroperoxides (KHPs) are oxygenated hydrocarbons that include carbonyl and peroxide functional groups. The decomposition pathways of KHPs are chain branching pathways in low temperature chemistry of alkanes and oxygenated biofuels, which makes KHPs critical intermediates in ignition processes in advanced combustion engines. In this work, KHP formation was investigated in the low temperature oxidation of a primary reference fuel (PRF 70), a binary mixture of 30 vol% n-heptane and 70 vol% iso-octane to represent a low octane number gasoline surrogate. Species were detected and measured in a jet-stirred reactor (JSR), coupled with time-of-flight molecular beam mass spectrometer using synchrotron vacuum-ultraviolet radiation as photon ionization source (SVUV-PI-TOF-MBMS) which provides in-situ measurement of unstable KHPs. Simultaneous KHPs production from higher reactivity n-heptane and lower reactivity iso-octane at similar temperatures was observed. Kinetic modeling was used to study the reactivity across a wide temperature range and to examine KHP formation chemistry. Specifically, signals vs. temperature profiles in experiments and mole fraction vs. temperature profiles in simulations, were compared to indicate the most possible saturated KHP isomers. Possible formation pathways for olefinic KHPs and di-olefinic KHPs are discussed. This work reports simultaneous formation of KHPs from two fuel molecules in a gasoline surrogate mixture, discusses important reaction pathways in low temperature oxidation, and explains simultaneous KHP production in n-heptane/iso-octane mixtures, i.e., low temperature oxidation of less reactive iso-octane is initiated by OH radicals produced from high reactivity n-heptane oxidation.

The development of sulfur host materials with simultaneous suppressed shuttle effect, improved electrical/ionic conductivity and high sulfur loading is highly desired for lithium-sulfur batteries. Herein, we proposed that two-dimensional heterostructures made of layered covalent triazine framework on Ti3C2 MXene nanosheets (CTF/TNS) as a sulfur host show multiple-in-one advantages for lithium-sulfur batteries. The integrity of organic CTF with ordered pore structure and inorganic TNSs with high conductivity imparts the heterostructures three-dimensional spatial confinement for high sulfur loading and efficient electron/ion transport for improved reaction kinetics. In addition, lithiophilic N sites in CTF and sulfurophilic Ti sites in TNSs enable dual-site chemical anchoring of polysulfides to effectively suppress shuttle effect. With a high sulfur loading of 76 wt%, the S@CTF/TNS cathode shows high reversible capacity (1441 mA h g−1 at 0.2 C), outstanding cycling stability (up to 1000 cycles at 1 C with a 0.014 % capacity decay rate per cycle) and excellent rate capability. Notably, even with a high areal sulfur loading of 5.6 mg cm−2, a high capacity retention of 94 % is still obtained after 100 cycles.

To report a patient with cyclic esotropia with a high accommodative convergence to accommodation (AC/A) ratio after surgical correction of intermittent exotropia who was found to have bilateral anomalous medial rectus muscle insertion sites. A 5-year-old girl developed intermittent esotropia on alternating days after undergoing bilateral lateral rectus recessions for correction of intermittent exotropia. Alternate prism and cover measurement of ocular alignment and binocular function was assessed on consecutive days. Surgical correction was performed for the full amount measured on a “crossed” day. On “straight” days, her eyes were orthotropic with normal binocular vision. Examination on “crossed” days revealed a left esotropia of 75 prism diopters (PD) at near fixation and 40 PD at distance fixation in primary gaze without fusion or stereopsis. The patient underwent bilateral medial rectus recessions in conjunction with posterior fixation sutures (MRP). During surgery, the distance from the limbus to the medial rectus muscle insertion was 3.5 mm bilaterally. Postoperatively, the cycle was broken, and the esotropia disappeared with no recurrence at the latest follow-up at 12 months. MRP is an effective procedure for correction of cyclic esotropia with a high AC/A ratio. Strabismus surgeons should design surgical strategies based on preoperative measurement of deviations at all distances and the anatomy of muscle insertions in patients with cyclic esotropia.

Mesoporous MgO micro-particles (20–80 μm) with crystalline phase framework wall were synthesized through a simple hydrothermal homogeneous precipitation route using urea as precipitating reagent. It possesses high specific area (278 m 2 /g), pseudo parallel pore and wall arrangement and large amount of basic sites and exhibits excellent catalytic activity for acetone condensation to mesityl oxide and isophorone even at low temperatures (

Small esters represent an important class of high octane biofuels for advanced spark ignition engines. They qualify for stringent fuel screening standards and could be synthesized through various pathways. In this work, we performed a detailed investigation of the combustion of two small esters, MA (methyl acetate) and EA (ethyl acetate), including quantum chemistry calculations, experimental studies of combustion characteristics and kinetic model development. The quantum chemistry calculations were performed to obtain rates for H-atom abstraction reactions involved in the oxidation chemistry of these fuels. The series of experiments include: a shock tube study to measure ignition delays at 15 and 30 bar, 1000-1450 K and equivalence ratios of 0.5, 1.0 and 2.0; laminar burning velocity measurements in a heat flux burner over a range of equivalence ratios [0.7-1.4] at atmospheric pressure and temperatures of 298 and 338 K; and speciation measurements during oxidation in a jet-stirred reactor at 800-1100 K for MA and 650-1000 K for EA at equivalence ratios of 0.5, 1.0 and at atmospheric pressure. The developed chemical kinetic mechanism for MA and EA incorporates reaction rates and pathways from recent studies along with rates calculated in this work. The new mechanism shows generally good agreement in predicting experimental data across the broad range of experimental conditions. The experimental data, along with the developed kinetic model, provides a solid groundwork towards improving the understanding the combustion chemistry of smaller esters. (C) 2018 The Combustion Institute. Published by Elsevier Inc. All rights reserved. The authors at KAUST acknowledge funding support from the Office of Sponsored Research under the Future Fuels Program. The authors at NUI Galway recognize funding support from Science Foundation Ireland via their Principal Investigator Program through project number 15/IA/3177. Cavallotti acknowledges the financial support of the Chemical Sciences and Engineering Division of Argonne National Laboratories for his sabbatical. The work by authors at LLNL was performed under the auspices of the U.S. Department of Energy (DOE), Contract DE-AC52-07NA27344 and was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies and Vehicle Technologies Offices. The authors at Lund University acknowledge financial support from the Centre for Combustion Science and Technology (CECOST), and Swedish Research Council (VR) via project 2015-04042. Part of this material is based on work at Argonne supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, under Contract No. DE-AC02-06CH11357. The NREL research was conducted as part of the Co-Optimization of Fuels & Engines (Co-Optima) project sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies and Vehicle Technologies Offices. peer-reviewed 2020-07-17

International audience; Alkylated cycloalkanes are an important chemical class in conventional fuels. Methylcyclohexane (MCH) is a simple alkylated cycloalkane that is a potential candidate to represent the naphthenic content in transportation fuel surrogates. Detailed experimental speciation data for MCH gas-phase oxidation and pyrolysis is still lacking in the literature. This work investigates the high-temperature pyrolysis and low-temperature oxidation of MCH in a jet-stirred reactor. Under low-temperature conditions, highly oxygenated intermediate species indicative of "alternative isomerization" of hydroperoxyalkylperoxy (OOQOOH) radicals and the subsequent third sequential O2 addition are presented. Furthermore, a detailed chemical kinetic model capable of predicting MCH combustion was developed using new thermodynamic group values and recently published rate coefficients. Alternative isomerization of OOQOOH radicals and third sequential O2 addition pathways were incorporated into the reaction mechanism. Additionally, an approach for reducing the complexity of the MCH low-temperature chemical pathways has been investigated to limit the arduousness of developing kinetic models. The experimentally measured species concentration profiles at atmospheric pressure, equivalence ratios of 0.25, 1.0, 2, and ∞, and temperatures in the range of 500-1100 K were used to validate and improve the chemical kinetic model. The model was further tested against rapid compression machine ignition delay times taken from literature.

In the absence of both positive and negative selection, DNA sequences evolve at the neutral rate, R = 1. Due to the prevalence of negative selection, R∼1 is rarely achieved in organismal evolution. However, when R ∼ 1 is observed, it does not necessarily indicate neutral evolution because positive and negative selection could be equally strong but in opposite directions - hereby referred to as quasi-neutrality. We now show that somatic-cell evolution could be the paradigm of quasi-neutral evolution for these reasons: 1) Quasi-neutrality is much more likely in small populations (size N < 50) than in large ones; 2) Stem cell population sizes in single niches of normal tissues, from which tumors likely emerges, have small N’s (usually < 50); 3) the genome-wide evolutionary rate across tissue types is close to R = 1; 4) Relative to the average of R ∼ 1, many genes evolve at a much higher or lower rate, thus hinting both positive and negative selection; 5) When N < 50, selection efficacy decreases rapidly as N decreases even when the selection intensity stays constant; 6) Notably, N is smaller in the small intestine (SmI) than in the colon (CO); hence, the ∼ 70 fold higher rate of phenotypic evolution (observed as cancer risk) in the latter can be explained by the greater efficacy of selection, which then leads to the fixation of more advantageous mutations and fewer deleterious ones in the CO. Under quasineutrality, positive and negative selection can be measured in the same system as the two forces are simultaneously present or absent.

PURPOSE To compare the clinical outcomes of bilateral medial rectus plication and resection for the treatment of convergence insufficiency (CI)-type intermittent exotropia (IXT). METHODS Fifty-five patients with CI-type IXT were included in this prospective study and were followed for 6 months. The patients were randomized into two groups: the bilateral medial rectus plication (BMRP) group (n = 27) and the bilateral medial rectus resection (BMRR) group (n = 28). The eye examinations of each patient were carried out before the surgery and at 1 day and 1, 3 and 6 months postoperatively. The success rate, angle of deviation, stereoacuity, operative time and postoperative conjunctival swelling and redness score were analysed. RESULTS The mean deviation at distance at 1 day postoperatively was +6.6 ± 5.6 prism dioptres (PD) in the BMRP group, which was lower than the value of +10.8 ± 9.3 PD observed in the BMRR group (p = 0.046). There was more overcorrection in the BMRR group at first day after surgery. However, there were no significant differences in deviations or success rates were observed between the two groups at 1, 3 and 6 months after surgery (p > 0.05). The operative time in the BMRP (12.9 ± 1.4 min) group was shorter than that in the BMRR (14.7 ± 1.4 min) group (p

This work identifies classes of cool flame intermediates from n-heptane low-temperature oxidation in a jet-stirred reactor (JSR) and a motored cooperative fuel research (CFR) engine. The sampled species from the JSR oxidation of a mixture of n-heptane/O2/Ar (0.01/0.11/0.88) were analyzed using a synchrotron vacuum ultraviolet radiation photoionization (SVUV-PI) time-of-flight molecular-beam mass spectrometer (MBMS) and an atmospheric pressure chemical ionization (APCI) Orbitrap mass spectrometer (OTMS). The OTMS was also used to analyze the sampled species from a CFR engine exhaust. Approximately 70 intermediates were detected by the SVUV-PI-MBMS, and their assigned molecular formulae are in good agreement with those detected by the APCI-OTMS, which has ultra-high mass resolving power and provides an accurate elemental C/H/O composition of the intermediate species. Furthermore, the results show that the species formed during the partial oxidation of n-heptane in the CFR engine are very similar to those produced in an ideal reactor, i.e., a JSR. The products can be classified by species with molecular formulae of C7H14Ox (x = 0–5), C7H12Ox (x = 0–4), C7H10Ox (x = 0–4), CnH2n (n = 2–6), CnH2n−2 (n = 4–6), CnH2n+2O (n = 1–4), CnH2nO (n = 1–6), CnH2n−2O (n = 2–6), CnH2n−4O (n = 4–6), CnH2n+2O2 (n = 0–4, 7), CnH2nO2 (n = 1–6), CnH2n−2O2 (n = 2–6), CnH2n−4O2 (n = 4–6), and CnH2nO3 (n = 3–6). The identified intermediate species include alkenes, dienes, aldehyde/keto compounds, olefinic aldehyde/keto compounds, diones, cyclic ethers, peroxides, acids, and alcohols/ethers. Reaction pathways forming these intermediates are proposed and discussed herein. These experimental results are important in the development of more accurate kinetic models for n-heptane and longer-chain alkanes.

Significance Highly oxygenated molecules are involved in autooxidation reactions leading to the formation of secondary organic aerosols (SOAs); they are also critical intermediates in autooxidation processes for liquid hydrogen degradation and the ignition of fuels in advanced combustion systems. However, these reactions are still poorly understood. In this study, we unveil a generalized reaction mechanism involving the autooxidation of peroxy radicals with at least three stages of sequential O2 addition. We elucidate important underlying kinetics and structural characteristics of autooxidation processes used for developing new technologies including those aimed at reducing climatically active SOAs and pollutants from fuel combustion. We show that advances can be made by bridging experimental and theoretical methods used by atmospheric and combustion scientists., Decades of research on the autooxidation of organic compounds have provided fundamental and practical insights into these processes; however, the structure of many key autooxidation intermediates and the reactions leading to their formation still remain unclear. This work provides additional experimental evidence that highly oxygenated intermediates with one or more hydroperoxy groups are prevalent in the autooxidation of various oxygenated (e.g., alcohol, aldehyde, keto compounds, ether, and ester) and nonoxygenated (e.g., normal alkane, branched alkane, and cycloalkane) organic compounds. These findings improve our understanding of autooxidation reaction mechanisms that are routinely used to predict fuel ignition and oxidative stability of liquid hydrocarbons, while also providing insights relevant to the formation mechanisms of tropospheric aerosol building blocks. The direct observation of highly oxygenated intermediates for the autooxidation of alkanes at 500–600 K builds upon prior observations made in atmospheric conditions for the autooxidation of terpenes and other unsaturated hydrocarbons; it shows that highly oxygenated intermediates are stable at conditions above room temperature. These results further reveal that highly oxygenated intermediates are not only accessible by chemical activation but also by thermal activation. Theoretical calculations on H-atom migration reactions are presented to rationalize the relationship between the organic compound’s molecular structure (n-alkane, branched alkane, and cycloalkane) and its propensity to produce highly oxygenated intermediates via extensive autooxidation of hydroperoxyalkylperoxy radicals. Finally, detailed chemical kinetic simulations demonstrate the influence of these additional reaction pathways on the ignition of practical fuels.

Transition metal oxides/carbon (TMOs/C) composites are important for high-performance lithium-ion batteries (LIBs), but the development of interface-stable TMOs/C composite anodes for robust lithium storage is still a challenge. Herein, mesoporous TiO

Learning from the idea of food fermentation, a facile and environmentally benign method has been developed for the preparation of 3D microorganism inspired hydrogels (MIH). To clarify the effect of temperature on the fermentation capacity of yeast, bubble coalescence, gelation time, pore shape and swelling behavior of MIH, a series of temperatures from 25 °C to 50 °C were set to synthesise super-/macro-porous polyacrylamide (PAM) hydrogels with fast response and hierarchical pore structure via an environmental friendly fermentation method. It is found that the gelation process of acrylamide and CO2 gas foaming process of yeast fermentation play decisive roles in controlling the pore structure and swelling behavior of PAM hydrogels. A mutual benefit on the fermentation and unique porous structure make HSYT hydrogels potentially applicable for drug delivery systems, food industries and chemical separation.

The lead-free solders are adopted to avoid lead pollution in the past decades, however, the mechanical behaviors under complex loading are still requires further study. For example, change of environment temperature is one of the hazards affecting the electronics reliability, especially the temperature cycles which will increase the temperature damage rapidly and the working life could be reduced. In the current study, the rate-dependent Johnson-Cook model is modified, and the temperature cycle related damage model is proposed. The pre-damage caused by temperature is considered. With the modification of damage model, the full failure process of solder can be described. In order to verify the proposed model, the temperature cycling experiments were conducted at recycle temperature ranges from 77.15∼398K and 77.15∼293K with different number of recycle times. The model is implemented by UMAT and conducted by the finite element software ABAQUS. The simulation results are compared with the experiments, and the developed model can simulate the behaviors (such as the change of strength and the plasticity) of Sn3.0Ag0.5Cu lead-free solder after temperature cycles with reasonable accuracy. Besides, the proposed model can be applied to measure the temperature recycle damage of solder, which is useful to evaluate its reliability under complex working conditions.

Structural reliability issues attract more and more attentions with the rapid development of electronic packaging industry. Sn-Ag-Cu alloys have long been used as solder materials for the interconnections of microelectronic devices because of low melting temperature and good wettability. Many tensile tests were performed on Sn-3Ag-0.5Cu solder alloys at various strain rates and over a wide temperature range [1]. And thermal cycling aging studies on a lead-free Sn-Ag-Cu solder joint were investigated [2]. In this study, a series of tensile tests of Sn-3Ag-0.5Cu were investigated at different number of cycles and different temperatures. The possible mechanism of tensile strength, ductility improvement were discussed. The samples were placed in liquid nitrogen environment at 77 K for 10 minutes and then 293K(398K) for 10 minutes as one thermal cycle. The number of cycles is 5, 15, 25 and 35. Thermal cycling induces changes in properties.

The realization of antipulverization electrode structures, especially using low-carbon-content anode materials, is crucial for developing high-energy and long-life lithium-ion batteries (LIBs); however, this technology remains challenging. This study shows that SnO2 triple-shelled hollow superstructures (TSHSs) with a low carbon content (4.83%) constructed by layer-by-layer assembly of various nanostructure units can withstand a huge volume expansion of ≈231.8% and deliver a high reversible capacity of 1099 mAh g-1 even after 1450 cycles. These values represent the best comprehensive performance in SnO2 -based anodes to date. Mechanics simulations and in situ transmission electron microscopy suggest that the TSHSs enable a self-synergistic structure-preservation behavior upon lithiation/delithiation, protecting the superstructures from collapse and guaranteeing the electrode structural integrity during long-term cycling. Specifically, the outer shells during lithiation processes are fully lithiated, preventing the overlithiation and the collapse of the inner shells; in turn, in delithiation processes, the underlithiated inner shells work as robust cores to support the huge volume contraction of the outer shells; meanwhile, the middle shells with abundant pores offer sufficient space to accommodate the volume change from the outer shell during both lithiation and delithiation. This study opens a new avenue in the development of high-performance LIBs for practical energy applications.

Importance Some uncertainty about the clinical value and dosing of atropine for the treatment of myopia in children remains. Objective To evaluate the efficacy vs the adverse effects of various doses of atropine in the therapy for myopia in children. Data Sources Data were obtained from PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials, from inception to April 30, 2016. The reference lists of published reviews and clinicaltrials.gov were searched for additional relevant studies. Key search terms included myopia , refractive errors , and atropine . Only studies published in English were included. Study Selection Randomized clinical trials and cohort studies that enrolled patients younger than 18 years with myopia who received atropine in at least 1 treatment arm and that reported the annual rate of myopia progression and/or any adverse effects of atropine therapy were included in the analysis. Data Extraction and Synthesis Two reviewers independently abstracted the data. Heterogeneity was statistically quantified by Q, H, and I 2 statistics, and a meta-analysis was performed using the random-effects model. The Cochrane Collaboration 6 aspects of bias and the Newcastle-Ottawa Scale were used to assess the risk for bias. Main Outcomes and Measures The primary outcome was a difference in efficacy and the presence of adverse effects at different doses of atropine vs control conditions. The secondary outcomes included the differences in adverse effects between Asian and white patients. Results Nineteen unique studies involving 3137 unique children were included in the analysis. The weighted mean differences between the atropine and control groups in myopia progression were 0.50 diopters (D) per year (95% CI, 0.24-0.76 D per year) for low-dose atropine, 0.57 D per year (95% CI, 0.43-0.71 D per year) for moderate-dose atropine, and 0.62 D per year (95% CI, 0.45-0.79 D per year) for high-dose atropine ( P d , 0.97, 1.76, and 1.94, respectively). All doses of atropine, therefore, were equally beneficial with respect to myopia progression ( P = .15). High-dose atropine were associated with more adverse effects, such as the 43.1% incidence of photophobia compared with 6.3% for low-dose atropine and 17.8% for moderate-dose atropine (χ 2 2 = 7.05; P = .03). In addition, differences in the incidence of adverse effects between Asian and white patients were not identified (χ 2 1 = 0.81; P = .37 for photophobia). Conclusions and Relevance This meta-analysis suggests that the efficacy of atropine is dose independent within this range, whereas the adverse effects are dose dependent.

This work examines the oxidation of a well-characterized, high-octane-number FACE (fuel for advanced combustion engines) F gasoline. Oxidation experiments were performed in a jet-stirred reactor (JSR) for FACE F gasoline under the following conditions: pressure, 10 bar; temperature, 530–1250 K; residence time, 0.7s; equivalence ratios, 0.5, 1.0, and 2.0. Detailed species profiles were achieved by identification and quantification from gas chromatography with mass spectrometry (GC-MS) and Fourier transform infrared spectrometry (FTIR). Four surrogates, with physical and chemical properties that mimic the real fuel properties, were used for simulations, with a detailed gasoline surrogate kinetic model. Fuel and species profiles were well-captured and -predicted by comparisons between experimental results and surrogate simulations. Further analysis was performed using a quantities of interest (QoI) approach to show the differences between experimental and simulation results and to evaluate the gasoline surro...

External electric fields may reduce emissions and improve combustion efficiency by active control of combustion processes. In-depth, quantitative understanding of ion chemistry in flames enables predictive models to describe the effect of external electric fields on combustion plasma. This study presents detailed cation profile measurements in low-pressure, burner-stabilized, methane/oxygen/argon flames. A quadrupole molecular beam mass spectrometer (MBMS) coupled to a low-pressure ( P = 30 Torr) combustion chamber was utilized to measure ion signals as a function of height above the burner. Lean, stoichiometric and rich flames were examined to evaluate the dependence of ion chemistry on flame stoichiometry. Additionally, for the first time, cataloging of flame cations is performed using a high mass resolution time-of-flight mass spectrometer (TOF-MS) to distinguish ions with the same nominal mass. In the lean and stoichiometric flames, the dominant ions were H 3 O + , CH 3 O 2 + , C 2 H 7 O + , C 2 H 3 O + and CH 5 O + , whereas large signals were measured for H 3 O + , C 3 H 3 + and C 2 H 3 O + in the rich flame. The spatial distribution of cations was compared with results from numerical simulations constrained by thermocouple-measured flame temperatures. Across all flames, the predicted H 3 O + decay rate was noticeably faster than observed experimentally. Sensitivity analysis showed that the mole fraction of H 3 O + is most sensitive to the rate of chemi-ionization CH + O ↔ CHO + + E − . To our knowledge, this work represents the first detailed measurements of positive ions in canonical low-pressure methane flames.

This paper presented a classification algorithm which could find the concept drifts from the data streams, called Incremental Updated Discriminant Eigenspace (IUDE). The algorithm constructs the eigenspace model of the data streams based on the algorithm of LDA (linear discriminant analysis). It handles the Gradual Concept Drifts by incremental update the Discriminant eigenspace. And at the same times, it uses the Mean Square Error (MSE) to handle the Abrupt Concept Drifts. The 1-nearest neighbour (1-NN) method classifies the new data streams. The experiment result shows that it is better flexibility over concept drifts than traditional approaches.

Based on the production of baking bread, rolls, cake, beer or Chinese steamed bread, a novel microorganism inspired macro/super-porous hydrogel composed of specific polymers and single-celled fungi, yeast, was prepared by the production of carbon dioxide (CO2) via a fermentation method. The appearance, porous structure, swelling behavior and adsorption properties of the resulting hydrogels were investigated by optical microscopy, scanning electron microscopy (SEM), UV/Vis spectroscopy and gravimetric methods. The resultant hydrogel presents a yellowish brown color similar to that of ale yeast, and the integration of polymeric materials and fungi has significantly improved the pore shape/size, swelling and adsorption properties of the hydrogels. Both super- and macro-pores with diameters ranging from 1 mm to 5 μm exist in the hierarchical matrix of the hydrogels. The super/macro-porous hydrogels can absorb water very rapidly and swell to an equilibrium state in less than 60 min. With increasing consumption of yeast or sugar, the adsorption capacity (Qt) of hydrogels can be increased by 1.39–1.87 times. After adsorbing cationic dye crystal violet (CV), pores of the hydrogel matrix were blocked and a dense layer was formed. By using same fermentation method porous fibers, elastomers, ceramics and metals could be obtained, which might have potential applications in the fields of cell culture, catalytic substrates, chemical separation and battery electrodes.

Structural reliability issues attract more and more attentions with the rapid development of electronic packaging industry. As the most venerable part of electronic packaging structure, the mechanical reliability of solder joints is greatly relevant to the system reliability of electronic products. The mechanical properties of solder materials have to be reasonably evaluated if numerical simulations are preferred compared with experimental studies. In the present study, a thermo-visco-plastic constitutive model is proposed for both lead-containing and lead-free solders under monotonic and cyclic loading conditions. Due to a simple formulation form and only a few parameters, the proposed thermo-visco-plastic constitutive model can be implemented into finite element software at minor effort and the determination of parameters can be achieved conveniently by regression to experimental data. The validations against experimental data show that the proposed model is capable of well simulating the tensile behavior of various solder materials at different strain rates and working temperatures. In addition, the required parameters in the proposed model are proved to be well defined as good changing patterns are achieved by revealing the intrinsic characteristic properties of solder material under various conditions.

To improve thermal-responsibility of poly N -isopropylacrylamide/inorganic hectorite hydrogels, inorganic hectorite severed as physical cross-linker, a kind of nonionic surfactant detergent polyoxyethylene 20 cetyl ether (POECE) was used as template to prepare nanostructured hydrogels (THPN hydrogels). The structure, morphology, temperature-sensitivity and swelling behavior of THPN hydrogels were characterized. Comparing to pure PNIPA hydrogel, THPN hydrogels exhibited higher swelling ratio as well as faster response rate. In the case of temperature-sensitivity, the volume phase transition temperature (VPTT) of THPN hydrogels was between 32 and 34 °C, slightly different from pure PNIPA hydrogel. The results of FTIR, 1 H NMR and TGA showed that a small amount of POECE adsorbed onto surface of hectorite, and it is maybe one of the reasons of higher swelling ratio and faster response rate. SEM and FESEM images showed that THPN hydrogels have more regular and smoother pore structure due to the POECE which severed as the effect of POECE template, and the hectorite dispersed homogeneously in THPN hydrogels regardless of adsorption of POECE, respectively.

The exploration of new and efficient energy storage mechanisms through nanostructured electrode design is crucial for the development of high-performance rechargeable batteries. Herein, black phosphorus quantum dots (BPQDs) and Ti3C2 nanosheets (TNSs) are employed as battery and pseudocapacitive components, respectively, to construct BPQD/TNS composite anodes with a novel battery-capacitive dual-model energy storage (DMES) mechanism for lithium-ion and sodium-ion batteries. Specifically, as a battery-type component, BPQDs anchored on the TNSs are endowed with improved conductivity and relieved stress upon cycling, enabling a high-capacity and stable energy storage. Meanwhile, the pseudocapacitive TNS component with further atomic charge polarization induced by POTi interfacial bonds between the two components allows enhanced charge adsorption and efficient interfacial electron transfer, contributing a higher pseudocapacitive value and fast energy storage. The DMES mechanism is evidenced by substantial characterizations of X-ray photoelectron spectroscopy and X-ray absorption fine structure spectroscopy, density functional theory calculations, and kinetics analyses. Consequently, the composite electrode exhibits superior battery performance, especially for lithium storage, such as high capacity (910 mAh g−1 at 100 mA g−1), long cycling stability (2400 cycles with a capacity retention over 100%), and high rate capability, representing the best comprehensive battery performance in BP-based anodes to date.

Local government's debt is now highly concerned by all levels of governments, it relates to the safety of China's economy, the research discusses the early warning of the local government's debt risk, It not only has theoretical significance but also has much more practical value. Based on the index selection of local government's debt risk and determination of risk range, We build early warning model of the local government's debt risk using the fuzzy comprehensive evaluation method, and apply the data of Jiangsu province to inspect the effectiveness of the early warning model, the research results show that the overall level of local government's debt risk is controllable in Jiangsu province.

Application of an oscillatory electric field is known to alter the separation distance between micron-scale colloidal particles and an adjacent electrode. This behavior is believed to be partially due to a lift force caused by electrohydrodynamic flow generated around each particle, with previous work focused on identifying a single steady-state “height” of the individual particles over the electrode. Here, we report the existence of a pronounced bifurcation in the particle height in response to low-frequency electric fields. Optical and confocal microscopy observations reveal that application of a ∼100 Hz field induces some of the particles to rapidly move several particle diameters up from the electrode, while the others move closer to the electrode. Statistics compiled from repeated trials demonstrate that the likelihood for a particle to move up follows a binomial distribution, indicating that the height bifurcation is random and does not result from membership in some distinct subpopulation of particles. The fraction of particles that move up increases with increased applied potential and decreased frequency, in a fashion qualitatively consistent with an energy landscape predicated on competition between electrohydrodynamic flow, colloidal interactions, and gravitational forces. Taken together, the results provide evidence for the existence of a deep tertiary minimum in the effective electrode-particle interaction potential at a surprisingly large distance from the electrode.

This paper narrated the origins of the environment development and things about engineering courses in our university. It analyzed issues about how to improve personal training and correct faultiness in current situation. According to the engineering specific area, using “TCP/IP protocol principle and network programming” as example, this paper discussed the methods about accelerating the process of electronic information engineering and stated the reason why it is necessary and significant to improve our teaching methods. Finally, it concluded the process and achievements in this decade.

Purpose. Amblyopia is the leading cause of visual impairment in children, affecting up to 4% of the general population. Several clinical trials evaluated the efficacy of levodopa versus placebo in treating amblyopia. However, the results appeared contradictory, suggesting both beneficial and ineffective. The aim of this study was to address the efficacy and tolerance of levodopa on amblyopia. Methods. Randomized controlled trials were identified and extracted from PubMed, EMBASE, Web of Science, and the Cochrane library. The quality of included trials was assessed by using Jadad score and heterogeneity was analyzed using chi-square test. Both efficacy and tolerance endpoints were evaluated. Data were extracted and analyzed using standard meta-analysis. Results. A total of 6 trials were identified from the search strategy. The pooled mean difference of endpoint logMAR of levodopa versus placebo was -0.11 (95% confidence interval -0.19~-0.02, p=0.01). Amblyopic patients receiving levodopa did not show significantly higher frequent adverse events than those receiving placebo. Conclusions. The use of levodopa is an effective and safe option for the treatment of amblyopia, and levodopa can be considered as first-line treatment of amblyopia.