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Based on the daily data of precipitation and runoff over the Longtan reservoir from 1960 to 2015,this paper selects four weight assignment methods to calculate the feature vector of flood season stages based on Fisher optimal dissection method,and analyzes the number of optimal flood season stages of the reservoir.The results show that:When ten days are used as the unit of flood season staging,the weight coefficients have little influence on the result of flood season staging.The flood season staging results of the Longtan reservoir based on the Fisher optimal dissection method can better reflect the characteristics of rainstorms and flood in the flood season of the basin,and the optimal number of flood season stages is five.According to the optimal staging results,the flood season in the Longtan reservoir is divided into pre-flood transition period (April 1~April 30),pre-flood period (May 1~May 20),main flood period (May 21~July 20),post-flood period (July 21~September 10) and post-flood transition period (September 11~October 31).

Objective To explore the predictive value of neutrophil-to-lymphocyte ratio(NLR) and platelet-to-lymphocyte ratio (PLR) in the prognosis and curative effect of locally advanced nasopharyngeal carcinoma(NPC) patients. Methods We collected the clinical information of locally advanced NPC patients from a randomized prospective clinical trial in Guizhou cancer hospital from July 2015 to December 2016. The patients were treated with two cycles of TPF induction chemotherapy and cisplatin-based concurrent chemoradiotherapy. The relationship between NLR, PLR before treatment and the therapeutic effect of patients was analyzed. We compared the curative effect between chrono-chemotherapy group and routine group. Results The mean values of NLR and PLR in stage Ⅳa/b patients were higher than those in stage Ⅲ patients (P=0.010); the immediate effect of metastatic lymph nodes in low PLR group was better than that in high PLR group (P=0.029), and the curative effect of primary lesion and overall curative effect three months after radiotherapy were better in low PLR group (P=0.012, P=0.027); there was no significant difference in immediate effect or overall curative effect three months after radiotherapy between conventional group and chronological group (P > 0.05). Conclusion NLR and PLR are related to the clinical staging of nasopharyngeal carcinoma. The later tumor stage is, the higher NLR and PLR values are. The predictive value of NLR for the patients' short-term efficacy is not well. PLR may be a predictor for recent outcomes of patients with locally advanced nasopharyngeal carcinoma, and high PLR may predict poor short-term efficacy.

Toxoplasmosis, a parasitic disease resulting from Toxoplasma gondii infection, remains prevalent worldwide, and causes great harm to immunodepressed patients, pregnant women and newborns. Although various molecular approaches to detect T. gondii infection are available, they are either costly or technically complex. This study aimed at developing a rapid visual detection assay using recombinase-aided amplification (RAA) and lateral flow dipstick (LFD) coupled with CRISPR-Cas13a fluorescence (RAA-Cas13a-LFD) to detect T. gondii. The RAA-Cas13a-LFD assay was performed in an incubator block at 37 °C within 2 h, and the amplification results were visualized and determined through LFD by the naked eye. The detection limit was 1 × 10−6 ng/μL by our developed RAA-Cas13a-LFD protocol, 100-fold higher than that by qPCR assay (1 × 10−8 ng/μL). No cross-reaction occurred either with the DNA of human blood or Ascaris lumbricoides, Digramma interrupta, Entamoeba coli, Fasciola gigantica, Plasmodium vivax, Schistosoma japonicum, Taenia solium, and Trichinella spiralis, and the positive rate by RAA-Cas13a-LFD assay was identical to that by qPCR assay (1.50% vs. 1.50%) in detecting T. gondii infection in the unknown blood samples obtained from clinical settings. Our findings demonstrate that this RAA-Cas13a-LFD assay is not only rapid, sensitive, and specific and allows direct visualization by the naked eye, but also eliminates sophisticated and costly equipment. More importantly, this technique can be applied to on-site surveillance of T. gondii.

The annual maximum flood magnitude and occurrence time are of great significance to the safe flood control and comprehensive benefits of reservoirs.Taking Changzhou reservoir as the example,this paper uses Von Mises function distribution and Pearson Type Ⅲ distribution to describe the time probability distribution of flood and probability distribution of peak discharge respectively,establishes the joint distribution of the two variables of the occurrence time and magnitudes of the annual maximum flood based on Frank Copula function,and describes the occurrence time distribution characteristics,joint return period and conditional return period of annual maximum flood in Changzhou reservoir.The results show that the joint distribution function based on Frank Copula function can fit both occurrence time and magnitudes of the annual maximum flood well,and can effectively mine the information of inflow flood,which can provide reference for the optimal dispatching and risk management.

Through systematic summary and problem analysis of domestic and foreign urban flood control design,this paper believes that the urban flood control design should develop from traditional water conservancy engineering design to a new stage of building urban waterfront space that integrates urban planning,ecological environment,garden landscape and other disciplines,and puts forward a new concept of urban flood control design based on urban waterfront space design.Through key measures such as the transformation of the water system in the connected area,the construction of green flexible ecological embankments,and the design of waterfront spaces shared by people and water,the waterfront spaces with urban public service functions can be created,which can effectively reduce the blocking of the ecological corridor between the city and the water system,better achieve the comprehensive effects of water security and aquatic ecology,as well as effectively promote the harmonious coexistence of city &water and the high-quality and sustainable development of the city under the premise of ensuring the safety of flood (tide) control.

With advantages of reasonable, rapid and accurate aid decision making, the urban waterlogging decision support system can comprehensively improve the ability of flood and waterlogging control. This paper systematically reviews the research progress of urban waterlogging decision support system and its application in large and medium-sized cities, points out the problems of low data accuracy, narrow research scope and slow calculation speed in system development and application, forecasts the development trend of the system, and puts forward several solutions, such as strengthening the multi-source data collection of urban waterlogging, improving the integrated forecasting of waterlogging in river basin and urban, and optimizing the overall calculation speed of the model.

The flood of the Xijiang River basin is formed by the heavy rain, with obvious seasonalvariation law, and the study of the flood season staging is of great significance to optimize theoperation of the reservoir and coordinate the contradiction between flood control and benefitpromotion. This paper studies the flood season staging of different stations in Xijiang River bythe fuzzy set analysis method, and comprehensively determines the stages of the flood season ofdifferent stations as follows: for Wuxuan station, the pre-flood period is from April 1 to May 26,the main flood period is from May 27 to August 15, and the post-flood period is from August 16 toOctober 31; for Dahuangjiangkou station, the pre-flood period is from April 1 to June 3, the mainflood period is from June 4 to August 14, and the post-flood period is from August 15 to October31; while for Wuzhou station: the pre-flood period is from April 1 to June 6, the main floodperiod is from June 7 to August 30, and the post-flood period is from August 31 to October 31. Theresults show that the period of the flood season staging of different stations in Xijiang isdifferent, and the period of flood season staging set by the fuzzy set analysis method isconsistent with that obtained from the actual flood control experience and the actual situation ofthe stations, which can provide the technical reference for the flood control & drought relief andthe optimal scheduling of the reservoir group.

BackgroundMetal tungsten (W) has a high melting point, low hydrogen solubility and high thermal conductivity. Therefore, it has been selected as one of the most promising plasma-facing materials for the future international thermonuclear experimental reactor (ITER).PurposeThis study aims to investigate the etching process of polycrystalline W induced by low energy hydrogen ion irradiation.MethodsPolycrystalline W materials were irradiated with 130 eV hydrogen ions. The irradiation damage behavior of W was researched by scanning electron microscopy (SEM), conductive atomic force microscopy (CAFM), Energy Dispersive Spectrometer (EDS) and nano indentation.ResultsThe investigates show that when the irradiation dose of H ions increases from 1.0×1024 ions∙m-2 to 1.5×1025 ions∙m-2, the surface of W material experiences a periodic evolution process from forming bubbles with H aggregation, the bubbles becoming bigger at grain boundaries, and gradually diffusing to the grain surface, until the W surface layer falls off due to the rupture of H bubbles. The irradiation dose required for one period of evolution is about (6.0~8.0)×1024 ions∙m-2. Nano indentation measurements show that the surface hardness of W material decreases after H ion irradiation. No impurities, especially elements of C and O, are detected on the W surface by EDS.ConclusionsIt is verified that the evolution of the unstable damage layer on the W surface induced by irradiations of low energy H ion is the main reason for the etching of W material. This work is very important for further understanding of the etching mechanism of W surface induced by H ion irradiation under the condition that the energy of irradiated H ion is lower than the sputtering threshold energy.

With heterogeneous catalysts, chemical promotion takes place at their surfaces. Even in the case of single-atom alloys, where small quantities of a reactive metal are dispersed within the main host, it is assumed that both elements are exposed and available to bond with the reactants. Here, we show, on the basis of in situ X-ray absorption spectroscopy data, that in alloy catalysts made from Pt highly diluted in Cu the Pt atoms are located at the inner interface between the metal nanoparticles and the silica support instead. Kinetic experiments indicated that these catalysts still display better selectivity for the hydrogenation of unsaturated aldehydes to unsaturated alcohols than the pure metals. Density functional theory calculations corroborated the stability of Pt at the metal-support interface and explained the catalytic performance as being due to a remote lowering of the activation barrier for the dissociation of H2 at Cu sites by the internal Pt atoms.

roadheader; cutting head; coal and rock property; load analysis; firmness coefficient

“Red/blue spot” is a common undesirable phenomenon in small and medium-sized TFT-LCD products, which directly affects the display quality of the product. It has always been a difficult problem in the display industry, which greatly reduces the market competitiveness of corresponding products. In this work, pressure tests are carried out on liquid crystal panels with different sizes and resolutions. The effects of different factors such as the flatness of the photo space, the distribution density of the spacers, and the glass thickness on the “red/blue spot” are compared. By increasing the flatness of the PS station, the septum distribution density, and the thickness of the glass, the sample’s anti-extrusion ability can be increased by 46.1%, 30%, and 23.1%, respectively. The experimental results can provide the basis for industry to further improve quality of products.

The effects of different concentrations of gallic acid (0 mg/g, 1 mg/g, 2 mg/g, 4 mg/g, and 6 mg/g) on the physicochemical properties of Lateolabrax japonicas myofibrillar protein were studied with 400 W ultrasound. The results showed that gallic acid decreased the particle size, total sulfhydryl group, carbonyl and dimer tyrosine content and Ca2+-ATPase activity (P

The last study on n-alkanes in surface sediments of Taihu Lake was in 2000, only 13 surface sediment samples were analysed, in order to have a comprehensive and up-to-date understanding of n-alkanes in the surface sediments of Taihu Lake, 41 surface sediment samples were analyzed by GC-MS. C10 to C37 were detected, the total concentrations of n-alkanes ranged from 2109 ng g−1 to 9096 ng g−1 (dry weight). There was strong odd carbon predominance in long chain n-alkanes and even carbon predominance in short chain n-alkanes. When this finding was combined with the analysis results of wax n-alkanes (WaxCn), carbon preference index (CPI), unresolved complex mixture (UCM), hopanes and steranes, it was considered that the long chain n-alkanes were mainly from terrigenous higher plants, and that the short chain n-alkanes mainly originated from bacteria and algae in the lake, compared with previous studies, there were no obvious anthropogenic petrogenic inputs. Terrestrial and aquatic hydrocarbons ratio (TAR) and C21−/C25+ indicated that terrigenous input was higher than aquatic sources and the nearshore n-alkanes were mainly from land-derived sources. Moreover, the distribution of short chain n-alkanes presented a relatively uniform pattern, while the long chain n-alkanes presented a trend that concentrations dropped from nearshore places to the middle of lake.

Photodynamic therapy (PDT) is a promising cancer treatment but has limitations due to its dependence on oxygen and high-power-density photoexcitation. Here, we report polymer-based organic photosensitizers (PSs) through rational PS skeleton design and precise side-chain engineering to generate •O2- and •OH under oxygen-free conditions using ultralow-power 808 nm photoexcitation for tumor-specific photodynamic ablation. The designed organic PS skeletons can generate electron-hole pairs to sensitize H2O into •O2- and •OH under oxygen-free conditions with 808 nm photoexcitation, achieving NIR-photoexcited and oxygen-independent •O2- and •OH production. Further, compared with commonly used alkyl side chains, glycol oligomer as the PS side chain mitigates electron-hole recombination and offers more H2O molecules around the electron-hole pairs generated from the hydrophobic PS skeletons, which can yield 4-fold stronger •O2- and •OH production, thus allowing an ultralow-power photoexcitation to yield high PDT effect. Finally, the feasibility of developing activatable PSs for tumor-specific photodynamic therapy in female mice is further demonstrated under 808 nm irradiation with an ultralow-power of 15 mW cm-2. The study not only provides further insights into the PDT mechanism but also offers a general design guideline to develop an oxygen-independent organic PS using ultralow-power NIR photoexcitation for tumor-specific PDT.