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Two-dimensional layered materials are a new class of materials that have emerged in recent years. Usually, it is formed by strong covalent bonds or ionic bonds within the layers. The interlayer are stacked together by weak Van der Waals force. The purpose of this paper is to investigate the role of the band structure of materials in experimental research, and other physical properties, in order to prepare the material into a device. Measuring its two-dimensional optical characteristics under an optical microscope can understand the use scenarios and development trends of 2D materials in electronics initially. At present, graphene is the hottest research on the market, and it is also the first discovered two-dimensional material, it is characterized by a working belt bandwidth, good optical reflectivity, and short reaction time, but the graphene material itself is the electronic structure with zero band gap .especially with a low damage threshold and a small adjustable modulation depth, In particular, its low damage threshold, small adjustable area in the adjustment breadth and its poor thermal effect limit its role in the field of high-energy lasers. Especially the characteristics of Low damage threshold and small adjustable modulation depth, especially low damage threshold, small adjustable area in adjustment breadth and poor thermal effect etc. limit its role in the field of high-energy lasers. In this paper, obtain the plasma characteristics of the nanostructured surface of graphene by using s-SNOM and chemical vapor deposition. And relate the Plasma size on the plasma surface nanopattern to the excited wavelength and structure closely in a certain mode, and enhance resonance in a gap of 25 nm wide; and using s-SNOM to study other methods for preparing characteristic structure of plasma on the surface of graphene nanomaterials. The experimental results show that molybdenum disulfide is the material that can reflects the two-dimensional layered structure best, its optical properties are related to the number of layers closely. Moreover, for the construction of photovoltaic devices, photodetector and light emitters, it is important to study different nanostructures using scattering near-field optical microscopy. It is important to study different nanostructures by scattering near-field optical microscopy. Infrared light excites the optical properties of graphene and molybdenum disulfide. [ABSTRACT FROM AUTHOR]

Composite organogels based on 1,3,5-tris(4-dodecyloxybenzoylamino)phenylbenzene (DBAPB), a known gelator, and N,N′-di(octadecyl)-perylene-3,4,9,10-tetracarboxylic diimide (C18PTCDI), a nongelator dye, have been achieved, leading to controllable color and emitting color changes. SEM images and XRD patterns revealed that the packing of the DBAPB-based gelator could almost be maintained in the composite gels. The temperature-dependent UV−vis absorption and temperature-dependent fluorescence emission spectra illustrated that the color and emitting color of the composite gels could be controlled by the content of C18PTCDIas well as the temperature in the gel phases. When the content of C18PTCDIwas 1 mol %, C18PTCDIcould be isolated as unimolecules in the composite gel, which was yellow and gave bright greenish-yellow emission under 365 nm light. For the mixed systems containing 2−10 mol % C18PTCDI, the fresh gels, which were obtained after cooling the hot solutions for a short time, were yellow and produced greenish-yellow emission under 365 nm illumination. However, the corresponding stable composite gels, which were obtained via prolonging the cooling time, were red and emitted weak red emission excited by UV light as a result of the formation of C18PTCDIaggregates. The reversible color and emitting color changes could be realized in the gel phases over a narrow temperature range. Moreover, the excitation energy of DBAPBcould be transferred to C18PTCDIin the composite gels, leading to obvious emission quenching of the former. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "The Presence of Hypothermia Within 24 Hours of Sepsis Diagnosis Predicts Persistent Lymphopenia," by A. M. Drewry and colleagues in the 2015 issue.

Suppressor of cytokine signaling 2 (SOCS2) plays an essential role in a number of physiological phenomena and functions as a tumor suppressor. Understanding the predictive effects of SOCS2 on non-small cell lung cancer (NSCLC) is urgently needed. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to assess SOCS2 gene expression levels in NSCLC. The clinical significance of SOCS2 was evaluated through Kaplan-Meier curve analysis and the analysis of related clinical factors. Gene Set Enrichment Analysis (GSEA) was used to identify the biological functions of SOCS2. Subsequently proliferation, wound-healing, colony formation and Transwell assays, and carboplatin drug experiments were used for verification. The results revealed that SOCS2 expression was low in the NSCLC tissues of patients in TCGA and GEO database analyses. Downregulated SOCS2 was associated with poor prognosis, as determined by Kaplan-Meier survival analysis (HR 0.61, 95% CI 0.52-0.73; P<0.001). GSEA showed that SOCS2 was involved in intracellular reactions, including epithelial-mesenchymal transition (EMT). Cell experiments indicated that knockdown of SOCS2 caused the malignant progression of NSCLC cell lines. Furthermore, the drug experiment showed that silencing of SOCS2 promoted the resistance of NSCLC cells to carboplatin. In conclusion, low expression of SOCS2 was associated with poor clinical prognosis by effecting EMT and causing drug resistance in NSCLC cell lines. Furthermore, SOCS2 could act as a predictive indicator for NSCLC. [ABSTRACT FROM AUTHOR]

A bogie system is the key equipment of railway vehicles. Rigorous practical evaluation of bogies is still a challenge. Presently, there is overreliance on part-specific experiments in practice. In the present work, a risk evaluation index system of a bogie system has been established based on the inspection data and experts' evaluation. Then, considering quantitative and qualitative aspects, the risk state of a bogie system has been evaluated using an extension theory and an entropy weight method. Finally, the method has been used to assess the bogie system of four different samples. Results show that this method can assess the risk state of a bogie system exactly. [ABSTRACT FROM AUTHOR]

The differences among polymers containing silicon or phosphorus, 20% polyhedral oligomeric silsesquioxane polyimide (20%-POSS-PI), 30% polysiloxane- block -polyimides (30%-PSX-PI), poly(siloxane imide) homopolymer (PSX-PI), and arylene ether phosphine oxide homopolymer (P-PPO), on mass loss, erosion yield, and surface morphology were elucidated. The tolerance against atomic oxygen (AO) was improved versus Kapton®H after introducing silicon or phosphorus to the polymers. The relative order of the mass loss was PSX-PI < P-PPO < 20%-POSS-PI < 30%-PSX-PI. In contrast, the erosion yields of 30%-PSX-PI, 20%-POSS-PI, and P-PPO decreased by orders of magnitude (PSX-PI declined by about two orders). The surface of Kapton®H was seriously eroded by AO exhibiting a "carpet-like" shape, and the roughness of the surface of Kapton®H became remarkable as the AO fluence increased. PSX-PI, P-PPO, 20%-POSS-PI, and 30%-PSX-PI at an AO fluence of 5.2 × 1020 atoms/cm2 had different surface morphologies, and the relative order of the surface roughness was PSX-PI < 30%-PSX-PI < 20%-POSS-PI < P-PPO. The 30%-PSX-PI and PSX-PI had minor mass losses and a smooth surface. This kind of material might replace inorganic coatings for applications in low earth orbit. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Iron Parameters Determine the Prognosis of Critically Ill Patients," in the 2016 issue.

The large-flowered Chinese chrysanthemum is one of the most morphologically complex ornamental plants, and its identification and classification requires a welldefined and reproducible system. The diversity of the capitulum is determined mainly by multiple shapes of ray florets. However, the existing classification systems for ray floret types are incomplete and unsystematic. In this study, 299 ray florets from 151 large- flowered chrysanthemum varieties in China, as well as 12 related traits of ray florets, were selected for quantitative classification. First, as one of the most important indices of ray floret shape, the corolla tube merged degree (CTMD) was defined as the corolla tube length/ray floret length (CTL/RFL). Combined with a probability grading method and linear regression analysis, the CTMD was divided into three groups, flat, spoon, and tubular, of which the CTL/RFL ranged from 0 to 0.20, 0.20 to 0.60, and 0.60 to 1.00, respectively. Second, Q-mode cluster analysis indicated that each group could be further categorized into three types (straight, curved, and atypical), based on other important variables in the ray floret. Finally, the ray floret was classified into nine types, including flat-straight, flat-curve, flat-atypical, spoon-straight, spoon-curve, spoon-atypical, tubular-straight, tubular-curve, and tubular-atypical. This ray floret classification system will be valuable in the classification of capitulum shape and has significance for the identification, breeding, and international standardization of chrysanthemum cultivars. [ABSTRACT FROM AUTHOR]

Background Thoracoscopic-laparoscopic procedures have been used more in the operations of esophagus cancer; in most times we call it minimally invasive esophagectomy, which is becoming mature. However, the efficacy of minimally invasive esophagectomy is still unclear, especially about the dissection of lymph nodes and survival. Methods A retrospective review was performed. The development process of minimally invasive esophagectomy for esophageal cancer was divided into three stages: the first stage 20, the second stage 37, the third stage 50. Result Total 107 patients underwent minimally invasive esophagectomy between July 2010 and May 2015. The number of lymph node resected during the three stages increased significantly, with a mean of 12.65, 15.91, and 20.16 nodes, respectively (p = 0.0075). The number of lymph nodes dissection greater than or equal to 12 or 18 increased significantly (p = 0.000). The patients from the first and the second stages had the similar 2-year survival rate (p = 0.8618). There is no significant difference in the 2-year disease-free survival rate (p = 0.606). Conclusion Surgeons accumulate experience on lymphadenectomy during minimally invasive esophagectomy as time goes by, and experience on 50 to 60 cases is essential and necessary to accomplish an apparent progress. [ABSTRACT FROM AUTHOR]

Silymarin is a traditional therapeutic used to protect the liver, acting to oppose lipid peroxidation, to enhance liver regeneration and functioning as an antioxidant. However, the effects of silymarin on pulmonary vascular dysfunction have not been investigated. In the present study, the modulatory effects of silymarin on pulmonary vascular dysfunction and the underlying mechanisms behind this were investigated in a lung ischemia-reperfusion (I/R) injury rat model. Male Sprague Dawley rats were randomly divided into 3 groups, including: i) A control group (n=10); ii) an I/R group (n=10); and iii) a silymarin-treated group (n=10). All experimental rats received 250 mg/kg/day of silymarin for 8 days. Silymarin was demonstrated to markedly improve lung I/R-induced pulmonary vascular dysfunction and lung moisture. Following silymarin treatment, inflammation and oxidative stress in the lung I/R-injury rats were demonstrably suppressed. Treatment with silymarin also inhibited the activation of caspase-3 and -9, and hypoxia inducible factor-1a (HIF-1α) and inducible nitric oxide synthase (iNOS) protein expression in the lung I/R-injury rats. Silymarin was concluded to impact upon pulmonary vascular dysfunction through the HIF-1α-iNOS pathway in the lung I/R injury rat model. [ABSTRACT FROM AUTHOR]

Objective: To study the expression of spleentyrosine kinase (Syk) gene in non--small--cell lung cancer and the relationship between Syk mRNA and microvessel density (MVD) in the tumor cells. Materials and Methods: The expression of Syk gene in 70 cases of lung tumor tissues, adjacent tissues, and normal lung tissues were examined with reverse transcription polymerase chain reaction (RT--PCR). The expression of MVD was examined with immunohistochemical streptavidin--biotin complex (SABC). The relation between them was analyzed. Results: Syk mRNA expression rates were 5.7, 95.7, and 100% in tumor, adjacent lung cells, and normal lung cells, respectively. The expression rate in tumor cells was significantly lower compared with those in normal lung tissue and adjacent lung tissue (P < 0.05), expression rate among different pathologic types, differentiation and clinical stages did not reveal any statistically significant differences (P > 0.05). The positive rate of CD34 in tumor was higher than that in adjacent tissues and normal lung tissues. The expression of Syk mRNA and MVD were negatively correlated. Conclusions: The lack of Syk mRNA expression in lung cancer play an important role in angiogenesis. [ABSTRACT FROM AUTHOR]

Background and Aims: Lung cancer has become one of the most dangerous malignant tumors in the world nowadays, whose pathogenesis is complex involving multi-genes and multi-elements. This study aims to investigate the values of spleen tyrosine kinase (Syk) and vascular endothelial growth factor-C (VEGF-C) in lymphangiogenesis and metastasis of lung adenocarcinoma A549 cells. Materials and Methods: The pcDNA3.1-VEGF-C and pLNCX-syk were constructed and transfected into A549 cells. After cells with stable expression were sorted, the level of VEGF-C was tested by RT-PCR and immunohistochemistry and the mRNA of syk was tested by RT-PCR. The cell invasion assay was investigated by transwell chamber in vitro. Restriction enzyme digestion and gel electrophoresis demonstrated successful construction of the pcDNA3.1-VEGF-C. Results: RT-PCR and immunohistochemistry revealed higher expression of VEGF-C in VEGFC-construct-transfected A549 cells than that in controls (P < 0.05). Successful construction of the pLNCX-syk was demonstrated by restriction enzyme electrophoresis and sequencing. RT-PCR revealed Syk expression higher in syk-construct-transfected cells than in controls (P < 0.05). Conclusions: The results indicate a potential link between the upregulation of Syk and VEGF-C expression and lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

The thermal expansion and phase transition of unpoled and poled [0 0 1]-oriented 0.69Pb(Mg1/3Nb2/3)O3-0.31PbTiO3 crystals are investigated using thermomechanical analysis, domain evolution, and dielectric measurement. Results of thermomechanical analysis show that the unpoled crystal exhibits negative thermal expansion at a temperature range from 30 °C to 120 °C, and the lattice parameter c of the tetragonal (T) phase is larger than those of the rhombohedral (R) and cubic (C) phases, i.e., cT > cR and cT > cC. Two additional structural modifications near 50 °C and 125 °C are detected in the unpoled crystal. Compared with that of the poled crystal, the T → C phase transition temperature of the unpoled crystal is relatively higher. An increase in temperature causes the unpoled crystal to undergo R → T → C phase transition, whereas R → M → T → C phase transition sequences are observed in the poled crystal. The phase transition behaviors are further verified by domain evolution and dielectric measurement. The significant differences between poled and unpoled crystals are attributed to the differences in their domain structures. [ABSTRACT FROM AUTHOR]

Two novel aromatic diamine monomer, 2,2'-bis[4-(5-amino-2-pyridinoxy)phenyl] hexafluoropropane (6FBAPDP) and 2,2'-bis[4-(5-amino-2-pyridinoxy)phenyl] propane (BAPDP), were successfully synthesized. Aimed at clarifying the structure-property relationships of pyridine-containing high-performance polymers, a series of novel fluorinated polyimides PI-(1-4) were prepared from 6FBAPDP with various commercially aromatic anhydrides, and polyimide (PI-5) was synthesized derived from BAPDP and 2,2'-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) via a two-stage process with heating imidization method. The fluorinated polyimides PI-(1-4) exhibited good solubility in strong polar solvents, such as N, N-dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, m-cresol, and could afford flexible, tough and transparent films with an UV-visible absorption cut-off wavelength at 342-393 nm. The glass transition temperatures of these polyimides were recorded between 239 and 306 °C by differential scanning calorimetry, and the 5% weight loss occurred at temperatures above 498 and 490 °C, in nitrogen and air, respectively. The polyimide films had the in-plane coefficients of thermal expansion (CTE) that ranged from 54 to 74 ppm °C-1. Moreover, the fluorinated polyimide films showed low moisture absorptions of 0.51-0.82% and outstanding mechanical properties with the tensile strengths of 75-100 MPa, tensile moduli of 3.2-4.0 GPa and elongation at break of 5.5-10.3%, good dielectric properties with low dielectric constants of 2.71-2.92 at 1 MHz. [ABSTRACT FROM AUTHOR]