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Background Aberrant expression of exosomal miRNAs has emerged as a research hotspot. However, no studies have been conducted on the dysregulation of exosomal miRNAs derived from cancer‐associated fibroblasts (CAFs) in supraglottic laryngeal squamous cell carcinoma (SLSCC). Methods Cancer‐associated fibroblasts and paired normal fibroblasts (NFs) from SLSCC patients were cultured, and exosomes in the culture supernatants were collected and identified. Exosomal miRNA expression was compared in each pair of CAFs and NFs by next‐generation sequencing, and expression of selected exosomal miRNAs was validated by reverse transcription‑quantitative PCR. Four online bioinformatic algorithms predicted the potential target genes of aberrantly expressed miRNAs, while gene ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment and network analysis identified downstream target genes and their interactions. Results Three pairs of CAFs and NFs were successfully cultured and purified. CAF‐derived exosomal miRNAs were mostly downregulated and included miR‐656‐3p, miR‐337‐5p, miR‐29a‐3p and miR‐655‐3p; however, some, including miR‐184‐3p, miR‐92a‐1‐5p, miR‐212‐3p and miR‐3135b, were upregulated. Bioinformatics analysis revealed involvement of these miRNAs in biological processes, cellular components and molecular functions. KEGG analysis revealed the top 30 pathways involvement in cancer initiation and progression and in cell cycle regulation. An interaction network showed miR‐16‐5p, miR‐29a‐3p, miR‐34c‐5p, miR‐32‐5p and miR‐490‐5p as the top five miRNAs and CCND1, CDKN1B, CDK6, PTEN and FOS as the top five target genes. Conclusions SLSCC patients showed aberrant expression of CAF‐derived exosomal miRNAs. The top five miRNAs and their target genes may jointly constitute a carcinogenic tumour microenvironment and act as biomarkers for SLSCC intervention., Twelve critical CAF‐derived exosomal miRNAs are identified in three supraglottic LSCC patients through next‐generation sequencing, which are further divided into top 5 and top 10 based on the expression level and the number of target genes. Ten critical target genes of these exosomal miRNAs are identified, which are further divided into top 5 and top 10 based on the number of upstream and downstream interacting miRNAs and target genes. Five of the top ten target genes are related to cell cycle regulation, indicating that the abnormal regulation of cell cycle plays a key role in the pathogenesis of supraglottic LSCC.

To develop Senecavirus A (SVA) virus-like particles (VLPs), a recombinant prokaryotic expression plasmid pET28a-SVA-VP031 was constructed to co-express SVA structural proteins VP0, VP3 and VP1, according to the genomic sequence of the field isolate CH-FJ-2017 after the recombinant proteins were expressed in E .coli system, and purified by Ni+ ion chromatographic method. The SVA VLPs self-assemble with a high yield in vitro buffer. A typical VLPs with an average diameter of 25-30 nm which is similar to native virions by using TEM detection. Animals immunized by SVA VLPs shown that the VLPs induced high titers neutralizing antibodies in Guinea pigs. This study indicated that the VLPs produced with co-expressing SVA structural proteins VP0, VP3 and VP1 in prokaryotic system is a promising candidate and laid an important foundation for the development of a novel SVA VLPs vaccine.

Alcohol consumption, which affects the structure and composition of the laryngeal microbiota, is one of the most important risk factors for laryngeal squamous cell cancer (LSCC). Our results demonstrated that high enrichment of

Glottic squamous cell carcinoma (GSCC) is the most prevalent type of laryngeal carcinoma. The value of prophylactic lymph node dissection (LND) in resected GSCC remains controversial. This study aims to quantitatively assess the probability of occult lymph node metastasis (LNM) for GSCC patients and devise individualized postoperative radiotherapy strategies.A total of 1319 patients with GSCC were retrospectively analyzed.GSCC patients with T1-T2 stages showed significantly lower LNM rate than those with T3-T4 stages. For patients with T3-T4 GSCC, multivariate logistic analyses indicated that three factors-maximum tumor diameter (MTD) of more than 2.0 cm, relatively low differentiation, and tumor invasive depth of no less than 1.0 cm-were independent risk factors for the existence of LNM. A predictive nomogram was established based on these factors. The accuracy and validity of our model were verified by 0.716 and remained at 0.717 after 1000 bootstrapping. The calibration curve was also plotted and showed a favorable agreement. The patients were stratified into two groups based on their individual LNM risk points. Possible LNM rates for low-risk and high-risk subgroups were 4.7% and 25.2%, respectively.A new post-operative strategy selection flow chart was established based on our newly created nomogram which can effectively predict the individualized possibility of occult LNM for GSCC patients. For clinical T3-4N0 patients in the high-risk subgroup, prophylactic dose post-operative radiation therapy is recommended. However, for all those clinically diagnosed as T1-2N0 stage, regular follow-up is sufficient in view of the low occult LNM rate.Level of Evidence: 2a.

Purpose: To compare the outcomes of tyrosine kinase inhibitors in combination with reduced-dose chemotherapy with those of standard induction chemotherapy and to compare the outcomes between TKIs with chemotherapy regimen and transplantation in adults with Philadelphia chromosome-positive acute lymphoblastic leukemia Methods: We retrospectively reviewed all patients treated with tyrosine kinase inhibitors in combination with chemotherapy. These patients were divided into the TKIs with reduced-dose chemotherapy group (62 patients) and the TKIs with standard chemotherapy group (143 patients). In further treatment, patients were divided into the transplant group (55 patients) and the non-transplant group (143 patients).Results: The complete remission rate (88.7% vs 83.9%, P=0.372) and early mortality rate (3.2% vs 3.5%, P=0.922) were similar between the TKIs with reduced-dose chemotherapy group and the TKIs with standard chemotherapy group. The proportions of lung infection (P=0.047) and bloodstream infection (P=0.024) and the proportion of patients with >21 days of hospitalization (P4 types of antibiotics (P=0.003), and on restrictive tigecycline and/or polymyxin (P=0.031) were higher in the standard chemotherapy group than in the TKIs with reduced-dose chemotherapy group. For cost analysis, the total costs and antimicrobial costs were higher in the standard chemotherapy group than in the TKIs with reduced-dose chemotherapy group. The 3-year overall survival rates and 3-year disease-free survival rates were significantly better in the transplant group than in the non-transplant group. Conclusion: An induction regimen combining TKIs with reduced-dose chemotherapy and transplantation in first CR remains a good option for patients with Ph+ALL.

Summary Nuclear Magnetic Resonance (NMR) log can provide accurate porosity independent of lithology , and NMR logging is more advantageous over conventional logs. In recent decades, it has been broadly applied in reservoir evaluation and pore structure study of sandstone and carbonate formations. But in igneous rocks, NMR porosity is underestimated compared to the actual porosity, which limits the application of NMR measurement in such reservoirs. To tackle this problem, NMR measurements were firstly introduced from DX, XS, and CPZ regions, China, and the effect of different igneous rocks on NMR porosity was analyzed in detail. NMR transvers relaxation time ( T2) of igneous rock is very short and the T2 distribution is in fast relaxation region, and the amplitude of NMR signals is so low. From NMR measurement analysis, NMR porosity relative error generally increases from acid, middle to mafic igneous rocks. Then, combined with element measurement, some influential factors were summarized from laboratory experiments and the relationships of NMR porosity relative error between different paramagnetic elements and magnetic susceptibility were investigated. The elemental analysis from plasma emission spectrometer showed that, NMR porosity relative error is related to paramagnetic mineral contents, and it generally increases as the iron and manganese contents increase. Moreover, the magnetic susceptibility of igneous rock is usually significantly greater than the sedimentary rocks, and from acid, middle to mafic igneous rocks, the magnetic susceptibility trends to increase. According the above analysis, some NMR porosity correction correlations are constructed. Finally, in case study from CPZ region, NMR logging porosity was correlated by the constructed correction correlation from iron content of element spectrum capture log, the corrected NMR porosity is in good agreement with core porosity, which proves the empirical correction method from the paramagnetic element contents reliable. Therefore, this study provides the foundation for NMR measurement correction and NMR logging interpretation of such complex igneous rocks formation.

A mixed potential ammonia sensor using In2O3 sensing electrode was prepared, and its sensing performance was enhanced by adjusting particle size with calcination heating rate as well as the utilization of NiCo2O4 reference electrode. It was found that the sensor with a calcination heating rate of 2 °C min−1 had the best performance, with a sensitivity of −61.27 mV decade−1 at 525 °C, and the TEM results showed that the average particle size was 70.36 nm. Furthermore, the sensor exhibited good stability against oxygen concentration fluctuation. The results also indicated that the mixed potential has a linear relationship with the logarithm of NH3 concentration, suggesting that the ammonia sensors in this study conform to the mixed potential theory. To address the issue that most ammonia sensors are susceptible to NO2 interference, NiCo2O4 was used as reference electrode to replace the Pt reference electrode, which could greatly offset the response of NO2 and improve the sensors selectivity. In summary, the developed In2O3/YSZ/NiCo2O4 sensor exhibited a great potential for NH3 monitoring in SCR systems.

Alcohol consumption, which affects the structure and composition of the laryngeal microbiota, is one of the most important risk factors for laryngeal squamous cell cancer (LSCC). Our results demonstrated that Fusobacterium nucleatum (F. nucleatum) highly enriched in LSCC was associated with poor prognosis. F. nucleatum increased miR-155-5p and miR-205-5p expression to suppress alcohol dehydrogenase 1B and transforming growth factor beta receptor 2 expression by activating TLR4- and MYD88-dependent innate immune signaling, resulting in ethanol metabolism reprogramming to accumulate F. nucleatum and PI3K/AKT signaling pathway activation to promote epithelial-mesenchymal transition in LSCC, further promoting uncontrolled LSCC progression and metastasis. Therefore, the positive feed-forward loop between F. nucleatum and ethanol metabolism reprogramming promotes cell proliferation, migration, and invasion to affect LSCC patient prognosis. The amount of F. nucleatum is a potential prognostic biomarker, a finding yielding valuable insight into clinical management and may potentially improving the oncologic outcome of LSCC patients.

Preoperative tracheotomy is an effective option that secures upper airway patency in laryngeal carcinoma patients suffering from upper airway obstruction, but the influence of this treatment on oncologic outcomes of laryngeal carcinoma remains controversial. The purpose of this study was to determine the impact of preoperative tracheotomy on overall survival in supraglottic carcinoma patients with tumor obstruction of the upper airway, and explore the potential causes.This retrospective study collected 243 consecutive patients with advanced stage supraglottic carcinoma from 2005 to 2010. Preoperative tracheotomy in the management of upper airway obstruction in patients with supraglottic carcinoma was analyzed.The mean age was 60.9 years at diagnosis, with men accounting for 98.4% of all patients. Thirty nine (16.0%) patients presenting with tumor obstruction of the upper airway required preoperative tracheotomy. T4 stage patients had higher rate of tracheotomy than those of patients with T3 stage (36.8% vs 12.2%). Patients with upper airway obstruction presented with greater tumor area compared with patients without (13.7 cmAdvanced stage supraglottic carcinoma patients with upper airway obstruction undergoing preoperative tracheotomy experienced worse overall survival. Advanced T stage and greater tumor size were associated with upper airway obstruction, indicating that the negative influence of tumor obstruction on survival may be cause by these two preoperative variables. Therefore, preoperative tracheotomy acts only as an alternative procedure, and is not a prognostic agent.

Sulfur dioxide (SO2) is one of the key pollutants in the atmosphere that should be monitored in many combustion facilities. In this paper, YSZ-based mixed potential SO2 sensors were developed utilizing the perovskite-type SrFeO3 sensing electrode, and Pd doping was applied to enhance the sensing performance. It was found that the sensor utilizing the Pd0.05-SrFeO3 sensing electrode showed the highest sensitivity toward 1–30 ppm SO2 at 575 ° C , and exhibited a piecewise linear relationship between Δ V and the logarithm of SO2 concentrations in this concentration range. The significant enhancement of sensing performances by 5 at% Pd doping was mainly attributed to the increasing of electrochemical catalytic activity of the anodic reaction. After the sensing performance test in the temperature range between 525 ° C –625 ° C , 575 ° C was selected as the optimum operating temperature. The sensing performances of the developed Pd0.05-SrFeO3 sensor were further evaluated at 575 ° C , exhibiting good selectivity to CO, CO2, NO, and NO2 interference and good long-term stability. In addition, the fluctuation of oxygen concentration can be corrected by the Butler-Volmer equation following the mixed potential theory.

Ag/SnO2 electrical contact material is currently recognized as the most promising environmentally friendly alternative material, but it has the problems of difficult processing and poor wettability between Ag matrix and SnO2 particles. Ag/SnO2Bi2O3CuO composite materials are prepared by reaction synthesis and powder metallurgy technology and the influence of different technology on the microstructure and properties are analyzed and discussed in this paper. The results indicate that the main phases in the Ag/SnO2Bi2O3CuO composite materials prepared by two kinds of technology are Ag, SnO2 and Bi2Sn2O7. The second phase oxide particles in Ag/SnO2Bi2O3CuO composite materials prepared by two kinds of technology mainly have six kinds of distribution position. The physical and mechanical properties of Ag/SnO2Bi2O3CuO composite materials prepared by reaction synthesis technology are better than those by powder metallurgy technology. In addition, the microstructure of Ag/SnO2Bi2O3CuO composite materials prepared by the reaction synthesis technology is more uniform and the distribution of the second phase oxide particles is more dispersive than that by powder metallurgy technology. The difference of microstructure of Ag/SnO2Bi2O3CuO prepared by two kinds of technology mainly occurs in the raw materials and the process of sintering and reaction.

Six interface models are constructed and used to find out the cohesion properties of W-ZrC interfaces through first principles calculations. It is revealed that interface orientation has an important effect on heat of formation and interface strength of W-ZrC interfaces, i.e., the W(110)-ZrC(111) interfaces with the Kurdjumov-Sachs (KS) relationship are not only energetically more favorable with more positive heats of formation, but also possess higher work of separation. Electronic structure calculations also show that the W-C bond fundamentally determines the magnitude of the interface cohesion between W and ZrC. The derived results are in good agreement with experimental observations in the literature, and could provide a deep understanding of cohesion properties of W-ZrC interfaces.

Electrical contact material's properties such as processability and switching behavior is strongly depend on the fabrication method. Here we present a study for evaluating the potential impact of fabrication technology for Ag/10SnO2 electrical contact materials. The result indicated that fabrication technology had an important influence on electrical contact physical phenomena, arc erosion morphology and arc erosion model of Ag/10SnO2 electrical contact materials. The mass change measured by volumetric method is 0.3765 mg larger than that of weighing method. In addition, the formation process and mechanism on arc erosion of Ag/10SnO2 electrical contact materials fabricated by different technology were discussed.

The influence of trace La on the oxidation of Ag-Sn alloy has been widely discussed. Here we present a detailed study for evaluating the potential impact of high content La for the oxidation of Ag-Sn alloy. We found that there are two kinds of intermetallic compounds in Ag-2Sn-4La alloy. The intermetallic compounds underwent a preferential oxidation, and the corresponded precipitation sequence of oxides was La2O3, La2Sn2O7 and SnO2. Based on the acquired insight, we suggest that high content La can accelerate the oxidation of Ag-Sn alloy oxidation but is not beneficial for the microstructure design of Ag-SnO2 electrical contact material.

Vision-based quadrotor will be a good carrier for big data. This paper investigates the quadrotor tracking control by designing an adaptive sliding mode controller based on the backstepping technique with the advantages of simplicity in design and ease of application. A sliding mode controller is first developed to ensure fast convergence speed with the desired reference, and then the backstepping technique is used until the desired reference trajectory is achieved and finally the appropriate control laws are obtained. In order to achieve the precise and fast localization of a quadrotor, a popular visual odometry algorithm is applied to gathering good position information required in motion estimation. We employ Kalman filter for sensor data fusion and state estimation. Gazebo is applied by creating a 3D dynamic environment to recreate the complex environment potentially encountered in the real world.

YSZ-based mixed-potential sensors with double-sensing electrodes were fabricated for ammonia (NH3) detection. ZnO and LaCoO3 nanoparticles prepared by flame spray pyrolysis (FSP) method were used as the sensing materials. The sensing responses of ZnO and LaCoO3 sensing electrodes can be overlapped based on the double-sensing-electrode structure, thereby significantly enhancing the sensitivity compared with the traditional mixed-potential sensors using Pt reference electrode. The sensitivities of this sensor reached up to -102.85, -75.312, -70.165, -48.616 mV/decade to 10–50 ppm NH3 at 450, 475, 500, 525 ℃ , respectively. Moreover, the NO2 interference effects on NH3 detection of ZnO and LaCoO3 electrodes were opposite and can be counteracted based on the double-sensing-electrode structure, eliminating most of the cross-sensitivity to NO2. The double-sensing-electrode sensor exhibited good performance under CO, CH4, NO, NO2 interference, oxygen fluctuation, and humidity variations, and showed good long-term stability. The results of sensing performance exhibited the sensors with double-sensing electrodes have a great potential for application on SCR system of diesel engines. In further studies, each sensing electrode can be optimized respectively and the sensitivity and selectivity of NH3 sensors could be enhanced to a higher level.

Estimation of S-wave velocity is one of the most critical steps for prestack seismic inversion. Based on the petrophysical model of fractured carbonate rocks, theoretical methods are firstly investigated for estimating P- and S-wave velocities in the presence of fractures. Then, the methods of calculating elastic properties in fractured carbonate rocks are discussed. The mineral concentration, total porosity, and fracture porosity from core X-ray diffraction and routine core measurements or log interpretation results are used to estimate the P- and S-wave velocities. In the given carbonate rock model, the elastic properties of carbonate rocks with different porosity and fractures are calculated. Two field tests prove that the proposed new method is effective and accurate. Furthermore, the model is useful for fluid identification, which is one of the most outstanding problems for carbonate reservoir description. The simulation results suggest that the larger the fracture porosity is, the easier fluid typing. In Tahe Oilfield, the elastic properties of different fluid zones indicate that bulk modulus and Young’s modulus are more sensitive to fluid than shear modulus, the Lamé constant, and Poisson’s ratio.

Three red oak derived lignin samples: 1. lignin extracted from red oak chips using γ-valerolactone (GVL lignin), 2. lignin extracted from the pyrolysis oil of red oak chips by fractionation and water extraction (pyrolytic lignin) and 3. pyrolytic lignin hydrogenated over Ru/C (hydrogenated pyrolytic lignin), were analyzed by FT-ICR MS, NMR, and GPC. More than 1100 distinct molecular weights were observed by FT-ICR MS of the lignin streams while changes in the O/C and H/C ratios suggested the dehydration of hydroxylated sidechains from pyrolysis and partial saturation of the compounds from hydrogenation. The relative average molecular weight of the lignin determined by GPC decreased five-fold after pyrolysis. Quantitative 13C, HSQC, and HMBC NMR revealed a decrease in the C–O aliphatics from pyrolysis potentially forming alkane, alkene, and carbonyl functionalities. The aldehydes and ketones were highly reactive during hydrogenation and may potentially be responsible for coke formation.

Penalty boundary intersection (PBI) is one popular method in decomposition based evolutionary multi-objective algorithms, where the penalty factor is crucial for striking a balance between convergence and diversity in a high-dimensional objective space. Meanwhile, the distribution of the obtained solutions highly depends on the setting of the weight vectors. This paper proposes an adaptive decomposition-based evolutionary algorithm for many-objective optimization, which introduces one adaptation mechanism for PBI-based decomposition and the other for adjusting the weight vector. The former assigns a specific penalty factor for each subproblem by using the distribution information of both population and the weight vectors, while the latter adjusts the weight vectors based on the objective ranges to handle problems with different scales on the objectives. We have compared the proposed algorithm with seven state-of-the-art many-objective evolutionary algorithms on a number of benchmark problems. The empirical results demonstrate the superiority of the proposed algorithm.

Hypopharyngeal squamous cell carcinoma (HSCC) is an aggressive disease with poor prognosis, yet studies have largely been more qualitatively focused. Our study aims to quantitatively predict the risk of occult contralateral lymph node metastasis (cLNM) for HSCC patients with ipsilateral lymph node metastasis (iLNM). This will be based on pre- and post-operative indexes to guide the selection of prophylactic contralateral lymph node dissection (cLND) and postoperative adjuvant treatments. Multivariate analyses of 462 primary HSCC patients with iLNM showed that the age of patients, subregions of tumor, pathological T (pT) stage, ipsiateral MLS and metastatic lymph node number (MLN), and lymph nodal necrosis were independent cLNM risk factors. These were used to construct two nomograms that can effectively predict the contralateral neck involvement in HSCC patients with ipsilateral positive lymph nodes. The first nomogram (pre-model) provides quantitative assessment on the necessity of cLND, while the second nomogram (post-model) informs regions of interest for therapeutic radiation. Overall, patients deemed high-risk of cLNM by pre-model should receive cLND. Post-operation, patients deemed high-risk of cLNM by post-model should receive therapeutic radiation targeting contralateral neck lymph nodes, moderate-risk group warrants comparatively lower dose contralaterally, while low-risk group requires only follow-up.

The aberrant expression of long non-coding RNA HOTAIR and transmethylase EZH2 played important roles in the progression and development of laryngeal squamous cell carcinoma (LSCC).This research was aimed to explore the expression and correlation with clinicopathological characteristics of HOTAIR and EZH2 in LSCC, and to evaluate the function of the two in regulating the proliferation and cis-platinum resistance processes of LSCC.Quantitative real time-PCR (qPCR) was conducted to measure the expression of HOTAIR and EZH2 in tissue samples. Clinicopathological features were collected and statistically analyzed combining with the expression of HOTAIR and EZH2. The variance of EZH2 with down-regulating HOTAIR was measured by qPCR. CCK-8 proliferation test was conducted to detect the proliferation feature in LSCC cells. After cultured with a series of cis-platinum concentrations for 24 h, cell viability was detected using CCK-8 assay, and the inhibition rates were calculated.HOTAIR and EZH2 were over-expressed in LSCC tissue. The higher expression was significantly related to T phase, pathological grades, and risk of lymphatic metastasis of LSCC. Suppressing HOTAIR expression stimulated EZH2 expressing, promoted the proliferation of AMC-HN8 cells, and increased the sensitivity to cis-platinum of the LSCC cells.

The oxidation mechanism of WC–Co cemented carbides during early oxidation stage was investigated by electron probe X-ray micro-analyser (EPMA), grazing incidence X-ray diffraction (GIXRD) and X-ray photoelectron spectroscopy (XPS). Temperature-time diagram of oxidation of WC–Co cemented carbides, obtained by EPMA results, can be divided into three regions, including (i) very slight oxidation, (ii) selective oxidation of the Co phase, and (iii) simultaneous oxidation of the Co and the WC phases. In region (ii), the Co phase will be completely oxidised while the WC phase only partly in a thin surface layer according to XPS results. Additionally, oxide scales mainly contains CoWO 4 with a little WO 3 according to GIXRD results. Contrarily, in region (iii), oxide scales mainly contains WO 3 with a little CoWO 4 . Finally, a schematic diagram of oxidation process was constructed.

The 1.5 mm thick Cu/Al composite sheet was obtained after explosive-welding and 6 passes cold rolling. The effects of annealing temperature and time on the microstructure, mechanical properties, and conductivity of cold-rolled Cu/Al composite sheets were investigated. The results show that the thickness of the interface diffusion layer with compounds of Al2Cu, AlCu, and Al4Cu9 increases with the increase in annealing temperature and holding time, and the total activation energy is 108 kJ mol−1. The tensile strength of composite sheets decreases and the fracture elongation increases with the increase of annealing temperature. Especially when the annealing temperature increased from 300 ℃ to 350 ℃, the tensile yield strength decreased from 225 MPa to 77 MPa, and the elongation increased from 16% to 37.5%. The tensile-shear strength of composite sheets reaches to 117 MPa after annealing at 400 ℃ for 2 h. The conductivity of composite sheet is greatly affected by the annealing time. At the annealing temperature of 350 ℃ and time of 4 h, the composite sheets show a better conductivity of 96.4% IACS.

The eco-friendly Ag/SnO2 composites are the most promising substitution of Ag/CdO contact materials, but the poor wettability between liquid Ag and SnO2 limits its industrial application. This paper presents the first study on influence of La2Sn2O7 on wettability between liquid Ag and SnO2. The wetting angle was measured by substrate drop method, and the microstructure and element diffusion in the wetting interface were analyzed by Electron Probe Micro-Analyzer. Results show that La2Sn2O7 decreases the wetting angle between liquid Ag and SnO2, and the wettability is the best when adding 25 wt% La2Sn2O7 at our all testing temperature. The interface between Ag and SnO2 changes from flat to wavy after adding La2Sn2O7. The diffusion and infiltration in the interface between Ag and La2Sn2O7 is significantly helpful to improve the wettability between Ag and SnO2.

Al–Cu, being a high-strength aluminium alloy, is used to prepared castings which are widely used in the automotive and aerospace industries as lightweight parts. However, corrosion is an issue. The Al–Cu alloys show improved properties when other elements are added to them. One such alloy is Al–4.5Cu–3.5Zn–0.5Mg. In order to improve the corrosion resistance and strength of this Al–4.5Cu–3.5Zn–0.5Mg cast alloy, a novel non-isothermal ageing (NIA) treatment was developed that comprised a heating stage up to 250 °C, followed by a cooling stage down to room temperature at the rate of 60 °C·h−1. Specimens were removed throughout the process and immediately quenched for morphological, mechanical, and electrochemical testing. The hardness continuously increased up to 124 HV with ageing time. The alloy exhibited optimal properties after ageing for ~340 min (with the aging temperature reaching 130 °C during the cooling stage of the NIA treatment), with a tensile strength and maximum corrosion depth of 395 MPa and 165 μm, respectively. Fine precipitates discontinuously appeared at the grain boundaries during the cooling stage. Some new fine Ω phases were precipitated in the grains, thereby narrowing the precipitation-free zone. Thus, high strength and good corrosion resistance of the alloy can be obtained via the NIA treatment. Notably, NIA treatments are less time-consuming than isothermal ageing treatments, thereby expanding the applications of high-strength cast aluminium alloys in the manufacturing industry.

Ag/Ni electrical contact materials tend to be weld together under high current and/or high temperature, which was a key problem to restrict the usage of Ag/Ni electric contact materials. Arc erosion characteristics of Ag/12Ni electrical contact material after 50,000 operations under direct current 19 V, 20 A and resistive load conditions were investigated. The result indicated that the probability distribution and change trend of arc energy and arc time during 50,000 operations were similar and the relationship between arc time and arc energy followed exponential function. On the one hand, “Crater” type erosion pit, island-like melted silver, pore, crack and coral-like structure spitting were observed on erosion surface of Ag/Ni contact materials. On the other hand, distribution of Ag and Ni element on molten pool of movable contact was different from that of stationary contact. For movable contact, element Ni mainly distributed on melted pool root, whereas element Ag mainly distributed inside of melted pool. For stationary contact, however, element Ni and Ag distributed layer by layer. Furthermore, arc erosion of stationary contact is more serious than that of movable contact. Keywords: Ag/Ni electrical contact material, Arc erosion, Erosion morphology, Element mapping

Substantial work in the literature has been devoted to studying emulsion stability caused by specific fractions of crude oil, such as asphaltenes or naphthenic acids. However, emulsion stability issues occur in the field with whole crude oil present and not just fractions. Understanding how all molecules in whole crude oils behave when the solubility parameter is varied could help to answer the question of what makes an emulsion stable from a molecular perspective. This work attempts to address solubility and the molecules that lead to emulsion stability from the whole crude oil perspective. Investigating the specific solubility class of molecules for emulsion stability limits understanding of interactions between different solubility classes, whether competitive or synergistic. In this work, emulsion stability and the composition of the interfacially active crude oil molecules are studied in parallel. Emulsion stability tests were performed with solutions containing different amounts of asphaltenes and h...

The oxidation experimental of WC–Co cemented carbides was carried out at 500 °C in air. Selective oxidation phenomenon of Co phase in WC–Co cemented carbides was observed and proved by EPMA and AFM. At first, the O content in Co phase increases quickly, and then tends to be stable after oxidation of 20 min. In sharp contrast, no change of O content in WC phase was observed. Moreover, it was found that the oxide scales thickness of Co phase increased parabolically with oxidation time. And thermodynamic and kinetic analysis of oxidation was done.

Based on theoretical analysis of internal oxidation kinetics, the local oxygen partial pressure within the internal oxidized Ag–3at.%Sn alloy was derived as a function of the ambient oxidization parameters firstly. Further combined with the interface structure stability diagram, the evolution of Ag/SnO2 interface structures in internal oxidization of Ag–3at.%Sn alloy has been quantitatively clarified. The prediction results indicates that the stoichiometric Ag/SnO2 interface dominates in internal oxidation of Ag–3at.%Sn alloy in air atmosphere at 973 K, while a gradient structures with both O-rich and stoichiometric interface were formed at the condition of 3 atm pure oxygen atmosphere at 873 K.

Thermochemical sulfate reduction (TSR) alters petroleum composition as it proceeds towards the complete oxidation of hydrocarbons to CO 2 . The effects of TSR on the molecular and isotopic composition of volatile species are well known; however, the non-volatile higher molecular weight aromatic and polar species have not been well documented. To address this deficiency, a suite of onshore Gulf coast oils and condensates generated from and accumulating in Smackover carbonates was assembled to include samples that experienced varying levels of TSR alteration and in reservoir thermal cracking. The entire molecular composition of aromatic hydrocarbons and NSO species were characterized and semi-quantified using comprehensive GC × GC (FID and CSD) and APPI–FTICR-MS. The concentration of thiadiamondoids is a reliable indicator of the extent of TSR alteration. Once generated by TSR, thiadiamondoids remain thermally stable in all but the most extreme reservoir temperatures (>180 °C). Hydrocarbon concentrations and distributions are influenced by thermal cracking and TSR. With increasing TSR alteration, oils become enriched in monoaromatic hydrocarbons and the distribution of high molecular weight aromatic hydrocarbons shifts towards more condensed species with a decrease in the number of alkyl carbons. Organosulfur compounds are created by the TSR process. In addition to the increase in benzothiophenes and dibenzothiophenes noted in previous studies, TSR generates condensed species containing one or more sulfur atoms that likely are composed of a single or multiple thiophenic cores. We hypothesize that these species are generated from the partial oxidation of PAHs and dealkylation reactions, followed by sulfur incorporation and condensation reactions. The organosulfur species remaining in the TSR altered oils are “proto-solid bitumen” moieties that upon further condensation, oxidation or sulfur incorporation result in highly sulfur enriched solid bitumen, which is chemically distinct from pyrobitumen formed by thermal cracking reactions. Although TSR involves the oxidation of hydrocarbons to CO 2 , prior studies of TSR-altered oils have not identified intermediate products. Using NESI–FTIRC-MS, the presence and distribution of oxygenated species become evident. All oils possess minor amounts of O 2 and O 4 species, presumable mono- and di-naphthenic acids originating from the source. As TSR progresses, the distribution of oxygenated species shifts towards increasing species with higher oxygen content, up to O 8 . Similar trends are observed for the SO x species. We hypothesize that these are partially oxidized condensed hydrocarbons and that these species are likely formed by the reaction proposed by Puttmann et al. (1989) for the oxidation of PAHs associated with Kupferschiefer mineralization, whereby hydrocarbons with aryl–aryl bonds incorporate sulfur to form thiophenic species. The rate of TSR is influenced by reservoir temperature and the presence of H 2 S. Typically, high reservoir temperatures (>140 °C) are needed for extensive TSR alteration to occur. Oil from the Gin Creek Field appears to have received a charge of H 2 S, presumably from TSR alteration of a down dip reservoir, which has accelerated the TSR reaction within a relatively cold reservoir (∼109 °C). This condition has allowed for the generation and preservation of abundant sulfur containing species that would be thermally cracked at higher temperatures.

Atmospheric solid analysis probe (ASAP) and atmospheric pressure gas chromatography (APGC) are relatively new ionization techniques. In this study, we applied these two techniques to characterize complex petroleum fraction samples under atmospheric pressure. The ion formation of petroleum standards (paraffins, isoparaffins, naphthenes and aromatic hydrocarbons) in ASAP and APGC was investigated. Two primary ionization pathways were observed, nitrogen fixation (addition) and charge transfer. Paraffins and isoparaffins standards are primarily ionized by nitrogen addition. Cyclic paraffins and aromatic compounds are primarily ionized by charge transfer. ASAP was applied to analyze a saturate fraction of petroleum vacuum resid under atmospheric pressure. An expanded composition coverage was demonstrated. APGC coupled with tandem mass spectrometry was demonstrated to characterize biomarkers in complex petroleum samples with high specificity, providing similar information as compared to the traditional gas chromatography electron ionization (GC–EI) under vacuum.

Objective: This study aimed to investigate the expression of Notch1 in human laryngeal squamous cell carcinoma (LSCC) tissues and its relationship to clinicopathologic characteristics as well as their prognostic value in LSCC. Methods: Samples from 106 patients with LSCC were analyzed for Notch1 expression by immunohistochemical staining. The relationship between Notch1 expression and clinicopathologic parameters was subsequently analyzed. Univariate analysis and multivariate analysis of patient survival were examined using the Kaplan-Meier method and Cox proportional hazards model, respectively. Results: We found that Notch1 had positive expression in 71 of 106 cases of LSCC (66.98%), which was obviously higher than laryngeal normal tissues ( P < .01) and significantly correlated with the clinical stage, lymph node metastasis, and histological grade (all Ps < .05). Univariate analysis revealed that Notch1 expression tended to show an unfavorable influence on overall survival (OS) and disease-free survival (DFS) (both Ps < .01). Multivariate analysis demonstrated that Notch1 was an independent prognostic factor for patients with LSCC ( P < .05). Conclusion: These results reveal that Notch1 expression is a potential prognostic factor for malignant progression, metastasis, and survival of LSCC patients. Furthermore, it has been demonstrated that high expression of Notch1 was associated with unfavorable OS and DFS in LSCC patients.

Evidence indicates that a hypoxic micro-environment plays an essential role in the regulation of cancer stem cells (CSCs). However, whether hypoxia is able to regulate the stem-like biological properties of laryngeal cancer cells remains unknown. In this study, we investigated the influence of hypoxia on the stemness of two laryngeal cancer cell lines, Hep-2 and AMC-HN-8. We cultured the two cell lines under hypoxia and normoxia and examined the influence of hypoxia on the expression of hypoxia-inducible factors (HIFs) and the cancer stem-like properties of these cells, including cell cycle distribution, expression of stem cell genes (OCT4, SOX2 and NANOG) and laryngeal CSC surface marker (CD133), proliferation, invasion, colony formation and sphere formation capacity. We determined that both of these cell lines, when maintained under hypoxic conditions, showed expanded cells in the G0/G1 phase, exhibited preferential expression of stem cell genes and CD133, and manifested upregulation of HIFs. When treated with hypoxia followed by normoxia exposure, the two cell lines exhibited enhanced capacities for proliferation, invasion, and sphere and colony formation compared with cells maintained consistently under normoxia. Our findings indicate that a hypoxic microenvironment may upgrade the stem-like biological properties of laryngeal cancer cell lines by the expansion of the CD133(+) stem cell fraction.

Retinal ganglion cells (RGCs) are projection neurons in the neural retina that relay visual information from the environment to the central nervous system. The early expression of MATH5 endows the post-mitotic precursors with RGC competence and leads to the activation of Brn3b that marks committed RGCs. Nevertheless, this fate commitment process and, specifically, regulation of Brn3b remain elusive. To explore the molecular mechanisms underlying RGC generation in the mouse retina, we analyzed the expression and function of Fez family zinc finger 2 (FEZF2), a transcription factor critical for the development of projection neurons in the cerebral cortex. Fezf2 mRNA and protein were transiently expressed at embryonic day 16.5 in the inner neuroblast layer and the prospective ganglion cell layer of the retina, respectively. Knockout of Fezf2 in the developing retina reduced BRN3B+ cells and increased apoptotic cell markers. Fezf2 knockdown by retinal in utero electroporation diminished BRN3B but not the coexpressed ISLET1 and BRN3A, indicating that the BRN3B decrease was the cause, not the result, of the overall reduction of BRN3B+ RGCs in the Fezf2 knockout retina. Moreover, the mRNA and promoter activity of Brn3b were increased in vitro by FEZF2, which bound to a 5′ regulatory fragment in the Brn3b genomic locus. These results indicate that transient expression of Fezf2 in the retina modulates the transcription of Brn3b and the survival of RGCs. This study improves our understanding of the transcriptional cascade required for the specification of RGCs and provides novel insights into the molecular basis of retinal development.

Mass spectrometry imaging (MSI) has emerged as an important tool in the last decade and it is beginning to show potential to provide new information in many fields owing to its unique ability to acquire molecularly specific images and to provide multiplexed information, without the need for labeling or staining. In MSI, the chemical identity of molecules present on a surface is investigated as a function of spatial distribution. In addition to now standard methods involving MSI in vacuum, recently developed ambient ionization techniques allow MSI to be performed under atmospheric pressure on untreated samples outside the mass spectrometer. Here we review recent developments and applications of MSI emphasizing the ambient ionization techniques of desorption electrospray ionization (DESI), laser ablation electrospray ionization (LAESI), probe electrospray ionization (PESI), desorption atmospheric pressure photoionization (DAPPI), femtosecond laser desorption ionization (fs-LDI), laser electrospray mass spectrometry (LEMS), infrared laser ablation metastable-induced chemical ionization (IR-LAMICI), liquid microjunction surface sampling probe mass spectrometry (LMJ-SSP MS), nanospray desorption electrospray ionization (nano-DESI), and plasma sources such as the low temperature plasma (LTP) probe and laser ablation coupled to flowing atmospheric-pressure afterglow (LA-FAPA). Included are discussions of some of the features of ambient MSI for example the ability to implement chemical reactions with the goal of providing high abundance ions characteristic of specific compounds of interest and the use of tandem mass spectrometry to either map the distribution of targeted molecules with high specificity or to provide additional MS information on the structural identification of compounds. We also describe the role of bioinformatics in acquiring and interpreting the chemical and spatial information obtained through MSI, especially in biological applications for tissue diagnostic purposes. Finally, we discuss the challenges in ambient MSI and include perspectives on the future of the field.

In the present study, powder internal oxidation and hot extrusion were used to prepare silver metal oxide (Ag-MeO) contact materials. Water atomized Ag–5.08 wt.%Sn–3.15 wt.%Sb alloy powders were internal oxidized and hot extruded with extrusion ratios of 49:4 and 49:1. The microstructures of composite powders and final products were studied by OM, SEM and TEM in details. The distribution of oxide particles in silver matrix are highly depended upon extrusion ratios. The oxide particles refined by the fracture of oxide clusters and distributed more uniform in the 49:1 extrusion. SnO2 and Ag1.7Sb2O5.77 are two kinds of reinforced particles identified. The influence of extrusion ratio and following anneal treatment on the properties, including of density, Vickers hardness and electric conductivity, were discussed. The best performance exhibited on the annealed sample of 49:1 extrusion, with density, Vickers hardness and electrical conductivity of 9.83 g/cm3, 91.6 HV and 71%IACS, respectively.

Thermochemical sulfate reduction (TSR) involves a complex series of redox reactions whereby petroleum is oxidized by sulfate forming H2S and CO2. A highly aromatic, sulfur rich carbonaceous residue, which we define as TSR-solid bitumen, is commonly seen in reservoir rocks where TSR has occurred. Using atmospheric pressure photoionization (APPI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry, we find that TSR altered oils and condensates contain highly condensed polynuclear aromatic and naphthenoaromatic species with 0–3 S atoms. These chemical species are not present in petroleum fluids of equivalent maturity that have not experienced TSR and must have been formed by the TSR process. We call these species proto-solid bitumen as they represent the type of organic compounds that could easily precipitate from the TSR altered oils with slight chemical alteration or changes in reservoir conditions.

Ambient ion soft landing, a process in which polyatomic ions are deposited from air onto a surface at a specified location under atmospheric pressure, is described. Ions generated by electrospray ionization are passed pneumatically through a heated metal drying tube, their ion polarity is selected using ion deflectors, and the dry selected ions are soft-landed onto a selected surface. Unlike the corresponding vacuum soft-landing experiment, where ions are mass-selected and soft-landed within a mass spectrometer, here the ions to be deposited are selected through the choice of a compound that gives predominantly one ionic species upon ambient ionization; no mass analysis is performed during the soft landing experiment. The desired dry ions, after electrical separation from neutrals and counterions, are deposited on a surface. Characterization of the landed material was achieved by dissolution and analysis using mass spectrometry or spectrofluorimetry. The treated surface was also characterized using fluorescence microscopy, which allowed surfaces patterned with fluorescent compounds to be imaged. The pure dry ions were used as reagents in heterogeneous ion/surface reactions including the reaction of pyrylium cations with d-lysine to form the N-substituted pyridinium cation. The charged microdroplets associated with incompletely dried ions could be selected for soft landing or surface reaction by choice of the temperature of a drying tube inserted between the ion source and the electrical ion deflectors.

The lipid composition of the human lens is distinct from most other tissues in that it is high in dihydrosphingomyelin and the most abundant glycerophospholipids in the lens are unusual 1-O-alkyl-ether linked phosphatidylethanolamines and phosphatidylserines. In this study, desorption electrospray ionization (DESI) mass spectrometry-imaging was used to determine the distribution of these lipids in the human lens along with other lipids including, ceramides, ceramide-1-phosphates, and lyso 1-O-alkyl ethers. To achieve this, 25 μm lens slices were mounted onto glass slides and analyzed using a linear ion-trap mass spectrometer equipped with a custom-built, 2-D automated DESI source. In contrast to other tissues that have been previously analyzed by DESI, the presence of a strong acid in the spray solvent was required to desorb lipids directly from lens tissue. Distinctive distributions were observed for [M + H](+) ions arising from each lipid class. Of particular interest were ionized 1-O-alkyl phosphatidylethanolamines and phosphatidylserines, PE (18:1e/18:1), and PS (18:1e/18:1), which were found in a thin ring in the outermost region of the lens. This distribution was confirmed by quantitative analysis of lenses that were sectioned into four distinct regions (outer, barrier, inner, and core), extracted and analyzed by electrospray ionization tandem mass spectrometry. DESI-imaging also revealed a complementary distribution for the structurally-related lyso 1-O-alkyl phosphatidylethanolamine, LPE (18:1e), which was localized closer to the centre of the lens. The data obtained in this study indicate that DESI-imaging is a powerful tool for determining the spatial distribution of human lens lipids.