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A graph is 1-planar if it can be drawn on the Euclidean plane so that each edge is crossed by at most one other edge. A proper vertex k-coloring of a graph G is defined as a vertex coloring from a set of k colors such that no two adjacent vertices have the same color. A graph that can be assigned a proper k-coloring is k-colorable. A cycle is a path of edges and vertices wherein a vertex is reachable from itself. A cycle contains k vertices and k edges is a k-cycle. In this paper, it is proved that 1-planar graphs without 4-cycles or 5-cycles are 5-colorable. [ABSTRACT FROM AUTHOR]

To investigate the values of 10-m drag coefficient (CD) in different coastal areas under the influence of tropical cyclones, the present study used the observational data from four towers in different coastal areas of the South China Sea (SCS) during six tropical cyclone (TC) passages, and employed the eddy covariance method and the flux profile method. The analysis of footprint showed that the fluxes at Zhizai Island (ZZI), Sanjiao Island (SJI) and Donghai Island (DHI) were influenced basically by the ocean, and the flux at Shangyang Town (SYT) was influenced mainly by the land. The results showed that the dependence relationships of CD on 10-m wind speed (U10) in four different coastal areas under the influence of TCs were different. CD at ZZI and SJI initially increased and then decreased as U10 increased, similar to the pattern over the ocean. CD at ZZI and SJI represented the values over shallow water with seawater depths of ~7 m and ~2 m, respectively. Moreover, the critical wind speed at which CD peaked gradually decreased as the seawater depth became shallower in the coastal areas. CD at DHI and SYT decreased monotonously as U10 increased, similar to the pattern over the land. CD at DHI represented the value over the transition zone from shallow water to coastal land, and CD at SYT represented the value over the coastal land. Meanwhile, the eddy covariance method and the flux profile method were compared at ZZI and SYT during TC passages. It was found that their CD values obtained by the two methods were close. Finally, the parameterizations of observed u* and CD as a function of U10 over four different coastal areas were given under the influence of high winds. These parameterizations of observed CD may be used in high-resolution numerical models for landfalling TC forecast. [ABSTRACT FROM AUTHOR]

Compactness and miniaturization have become increasingly important in the development of high-power microwave devices. Based on this rising demand, a novel C-band coaxial transit-time oscillator (TTO) with a low external guiding magnetic field is proposed and analyzed. The proposed device has the following advantages: simple structure, short axial length, high power conversion efficiency, and low external guiding magnetic field, which are of great significance for developing the compact and miniaturized high-power microwave devices. The application of a shorter axial length is made possible by the use of a transit radiation mechanism. Also, loading the opening foil symmetrically to both ends of the buncher helps reduce the external magnetic field of the proposed device. Unlike traditional foils, the proposed opening foil has a circular-hole; therefore, the electron beam will not bombard the conductive foil to generate plasma. This makes it possible to realize long pulse and high repetition rate operation of the device in future experiments. Through numerical calculation and PIC particle simulation, the stability of the intense relativistic electron beam (IREB) and the saturation time of the device are improved by using the conductive foil. The voltage and current of the diode are 548 kV and 11.4 kA, respectively. Under a 0.4-T external guiding magnetic field, a C-band output microwave with a frequency of 4.27 GHz and power of 1.88 GW can be generated. The power conversion efficiency of the proposed device is about 30%. [ABSTRACT FROM AUTHOR]

To explore the function of endogenous abscisic acid (ABA) in answer to excess zinc (Zn), calli from Arabidopsis (Arabidopsis thaliana) mutant lines, abi1-1 (ABA insensitive) and aba1-1 (with reduced level of ABA), and their associated wild-type (Landsberg erecta, Ler) were used. Excess Zn resulted in oxidative damage characterized by ion leakage, malondialdehyde (MDA), and hydrogen peroxide (H2O2) accumulation, and relative cell viability decrease in Arabidopsis calli. ABA-deficient mutant (aba-1) callus suffered more serious oxidative damage in comparison with wild-type (Ler) callus. Sodium tungstate, an ABA synthesis inhibitor, aggravated excess Zn-induced ion leakage, H2O2 and MDA accumulation in wild-type and aba1-1 mutant calli. Also, sodium tungstate obviously suppressed proline production and ascorbate peroxidase (APX) activity whereas promoted lipoxygenase (LOX) activity in wild-type and aba1-1 mutant calli in the presence of excess Zn. Instead, exogenous ABA treatment significantly elevated proline concentration and APX activity and inhibited LOX activity and thus alleviated excess Zn-induced ion leakage, H2O2 and MDA accumulation, and relative cell viability decrease in wild-type and aba-1 mutant calli. Moreover, no significant effects of sodium tungstate or exogenous ABA application on calli derived from abi1-1 mutant were observed under excess Zn. Endogenous ABA might function as a signal in exciting antioxidases and proline accumulation and thus protect against toxicity induced by excess Zn. [ABSTRACT FROM AUTHOR]

Com straw, rice straw and wheat straw were chosen as the substrates, and the effect of lime pretreatment time and temperature were comparatively examined by determination of the enzymatic transformation ratio. Results showed the yield of reducing sugar of wheat straw and rice straw could reach 60.38% and 46.77% respectively after lime pretreatment of 2h at the temperature of 90 °C. In contrast, corn straw needed more higher pretreated temperature of 121 °C for 1 h, whose yield of reducing sugar reached 56.82%. Wheat straw was more suitable for the pretreatment using lime. Further microstructural analysis of the straw samples was investigated by infrared spectrum, results showed that lime pretreatment could significantly degrade lignin in wheat straw. The selective degradation of lignin promoted the destruction of the spatial structure barrier of lignocellulosic macromolecules, retained more cellulose for later enzymatic saccharification, and improved straw enzymatic saccharification efficiency. [ABSTRACT FROM AUTHOR]

In traditional vulnerability assessments, a synthetic index method is usually used to select all types of social and economic indexes so that more aspects can be covered; however, the requisite social and economic data are not always available or are not highly relevant to the studied geographical space, which makes it difficult to conduct quantitative calculations. In this paper, a spatial value density assessment method was developed to improve the hazard of place model. First, a three-dimensional (3D) model of a coastal city was obtained using oblique airborne photogrammetry and image-based 3D reconstruction and then, architecture footprints were employed to extract the geometric information of each individual building. Additionally, a vulnerability assessment system was established to quantitatively account for the aggregate economic value of a selected set of urban surface features. Using geographic information system (GIS) techniques, the aggregate value of these urban features within each geographic unit can be accurately calculated to quantify the exposure and vulnerability of coastal cities to storm surge. A vulnerability assessment was conducted using Weihai city as an example. The study shows that vulnerability assessment accuracy was greatly improved by downscaling the assessment granularity from county-level administrative districts to a 1-km grid. [ABSTRACT FROM AUTHOR]

Key message: Shading could improve plant growth in Torreya grandis seedling, and 75 % shade is likely the optimum light irradiance level for its growth. Abstract: Light is a critical factor that affects the survival and early growth of tree seedlings. Torreya grandis, an economically important subtropical plant, is a shade-preferring species; however, the optimum light intensity for the growth of this species was still unclear. To determine the optimum light intensity, we examined the growth, chlorophyll fluorescence, gas exchange, and chloroplast ultrastructure of T. grandis seedlings growing under four levels of shade (i.e., 0, 50, 75, and 90 %). The results showed that T. grandis attained the greatest Pn and biomass when cultivated with 75 % shade. Seedlings grown under 75 % shade exhibited a 155 % increase in the height increment, a 440 % increase in the diameter increment, a 42.2 % increase in biomass, and a 102 % increase in the photosynthetic rate compared with seedlings grown in full sun. Moreover, 75 % shaded plants had the lowest antioxidant enzyme activities, malondialdehyde content and ion leakage. Full sunlight and 50 % shade significantly reduced the growth of T. grandis which was associated with a decrease in the maximal photochemical efficiency, photosynthetic rate, chlorophyll content and biomass compared with those under 75 % shade. Compared with the 75 % shaded plants, seedlings grown under 90 % shade had a reduced photosynthetic rate, which was accompanied by increased malondialdehyde content, relative electrolyte conductivity and antioxidant enzymes activities, suggesting that seedlings under the 90 % shade had the lower energy utilizing capacity. Higher antioxidant enzyme activities might be an efficient adaptation to protection against oxidative stress under low light conditions. Therefore, our results indicate that 75 % shade is likely the optimum light irradiance level for T. grandis seedling growth. [ABSTRACT FROM AUTHOR]

Despite considerable efficacy of arsenic trioxide (As2O3) in acute promyelocytic leukemia (APL) treatment, other non-APL leukemias, such as chronic myeloid leukemia (CML), are less sensitive to As2O3 treatment. However, the underlying mechanism is not well understood. Here we show that relative As2O3-resistant K562 cells have significantly lower ROS levels than As2O3-sensitive NB4 cells. We compared the expression of several antioxidant enzymes in these two cell lines and found that peroxiredoxin 1/2/6 and catalase are expressed at high levels in K562 cells. We further investigated the possible role of peroxirdoxin 1/2/6 and catalase in determining the cellular sensitivity to As2O3. Interestingly, knockdown of peroxiredoxin 1/2/6 did not increase the susceptibility of K562 cells to As2O3. On the contrary, knockdown of catalase markedly enhanced As2O3-induced apoptosis. In addition, we provide evidence that overexpression of BCR/ABL cannot increase the expression of PRDX 1/2/6 and catalase. The current study reveals that the functional role of antioxidant enzymes is cellular context and treatment agents dependent; targeting catalase may represent a novel strategy to improve the efficacy of As2O3 in CML treatment. [ABSTRACT FROM AUTHOR]

A novel coaxial relativistic transit-time oscillator with low guiding magnetic field is proposed and investigated to generate high power microwave at Ku-band. With the coaxial structure and a quasi body wave adopted as the operating mode, the device has a larger space-charge limiting current, higher power handling capacity, and lower guiding magnetic field. Moreover, for further improving the output power, a coaxial TM02 mode resonant reflector is well designed. Main structure parameters of the device are optimized by particle in cell simulations. A typical simulation result is that, with a 358 keV, 7.25 kA beam guided by a magnetic field of about 0.7 T, an 810 MW microwave pulse at 14.25 GHz is generated, yielding a conversion efficiency of about 31%. The primary experiments are also carried out. At a low guiding magnetic field of 0.7 T, a microwave pulse with power of 400 MW, pulse duration of 30 ns, frequency of 14.3 GHz close to the simulation one, and efficiency of 15.4% is generated. [ABSTRACT FROM PUBLISHER]

Since the reform and opening up, China's economic development has made great achievements, but it did not benefit all. The income gap among the famers expanded continuously, which not only exacerbated the problem of rural poverty and weakened the income growth of farmers, but also seriously affect the harmony and stability for the sustainable development of Chinese economy and society. This paper firstly analyzed by income decision equation cross-section data collected from 566 households of sample survey in Jiangsu, He'nan and Sichuan Provinces and determined the major factors affecting the farmer households' incomes. Secondly, it analyzed the contribution of each significant factor on the income differences between households by Shapley value decomposition. The results showed that the average outdoor-work time of household labor force during a year was the most important factor affecting households' income increase and differences in between. And the average education years of labors took the second place. Based on the above mentioned results, this paper suggested that speeding up the development of non-agricultural industries in rural areas, increasing the non-agricultural employment opportunities, adding financial input to rural education, and providing equal access to education and training to farmers will sustainably increase farmers' incomes, and reduce the differences between farmers incomes at the same time. [ABSTRACT FROM AUTHOR]

The removal of aggravating factors is important to reduce the severity of infantile eczema, but there are few studies on the assessment and identification of the aggravating factors in infantile eczema. Parents of children with infantile eczema ages 1 to 10 months ( N = 250) were recruited. Parents were required to complete a questionnaire. Two hundred forty-two (96.8%) children had skin dryness, 80% bathed with soap or shower gel, 82% often perspired, 84.8% wore tight-fitting clothes, 80.8% dressed in five layers of thick clothing, 85.6% were in contact with wool or feathers, and 59.2% were exposed to sunlight (>20 minutes/day). Eczema severity was greater after vaccination in 20%. Two hundred thirty-five mothers avoided eating potential food allergens (e.g., milk, egg whites, and fish), but this failed to improve the severity of symptoms in 93.6% of the children. Thirty patients had Neocate as a substitute for cow's milk, which resulted in symptom severity improvement in 10%. Thirty children were given food allergens, which exacerbated symptoms in 13.3%. One hundred twenty-eight (51.2%) of the children were treated with corticosteroid ointment; 62.5% had the ointment applied for only 2 to 3 days, and 6.2% had the corticosteroid ointment applied to weeping lesions. The vast majority of parents did not know about the aggravating factors for infantile eczema. The results demonstrated a strong need for educational programs to help parents understand and control infantile eczema. [ABSTRACT FROM AUTHOR]

The results from a hybrid approach that combines a mesoscale meteorological model with a diagnostic model to produce high-resolution wind fields in complex coastal topography are evaluated. The diagnostic wind model (California Meteorological Model, CALMET) with 100-m horizontal spacing was driven with outputs from the Weather Research and Forecasting (WRF) model to obtain near-surface winds for the 1-year period from 12 September 2003 to 11 September 2004. Results were compared with wind observations at four sites. Traditional statistical scores, including correlation coefficients, standard deviations (SDs) and mean absolute errors (MAEs), indicate that the wind estimates from the WRF/CALMET modeling system are produced reasonably well. The correlation coefficients are relatively large, ranging from 0.5 to 0.7 for the zonal wind component and from 0.75 to 0.85 for the meridional wind component. MAEs for wind speed range from 1.5 to 2.0 m s-1 at 10 meters above ground level (AGL) and from 2.0 to 2.5 m s-1 at 60 m AGL. MAEs for wind direction range from 30 to 40 degrees at both levels. A spectral decomposition of the time series of wind speed shows positive impacts of CALMET in improving the mesoscale winds. Moreover, combining the CALMET model with WRF significantly improves the spatial variability of the simulated wind fields. It can be concluded that the WRF/CALMET modeling system is capable of providing a detailed near-surface wind field, but the physics in the diagnostic CALMET model needs to be further improved. [ABSTRACT FROM AUTHOR]

Observational data of the severe typhoon Hagupit are obtained by a 3-dimensional ultrasonic anemometer which is installed on a 100-meter-high meteorological tower located at an islet off the coast of Guangdong. The characteristics of the extreme wind load parameters for offshore wind turbines under the influence of extreme winds at severe typhoon intensity are analyzed. By comparing the observed data with the results derived from the International Electrotechnical Commission (IEC) standard 61400-1, the applicability of the methods computing extreme wind load parameters in the IEC standard are investigated under typhoon conditions. The results are as follows. (1) The changes of both the offshore extreme gust wind speeds and the extreme wind directions render a \"M\" shape bi-modal distribution with peak values in the eyewall region of Hagupit. (2) There are significant differences of amplitudes of the observed extreme operating gust wind speeds and extreme wind direction from the results calculated from the IEC standard. (3) The amplitudes of both the extreme operating gust wind speeds and the extreme directions exceed the upper limits of the IEC standard for three standard classes of wind turbines, and the values calculated by IEC standard are much significantly larger than the measured ones. (4) The observed extreme operating gust wind speeds are consistent with the results calculated by the IEC standard when wind turbines are under full or partial workload or cut-off conditions, although the amplitude of extreme wind directions calculated in terms of the IEC standard is larger than that of direct measurements. Measured extreme operating gust wind speeds sometimes exceed the IEC design criteria. [ABSTRACT FROM AUTHOR]

Using the technique of smooth filtering and cylindrical filtering, the initial vortex circulation and large-scale environmental field were separated from the background field. Then the separated initial vortex circulation was translated and reinserted in the location where it was observed. This led to the determination of a method of initial vortex relocation. For seven tropical cyclones at 23 points of measurement time in the years of 2006 and 2007, two schemes, either directly adding a tropical cyclone bogus model in the background or adding it after the relocation of the initial vortex in the background field, were employed. Simulation experiments were compared. The results showed that the mean errors of the simulated tropical cyclone tracks at 24 and 48 hours were both smaller with the scheme of adding tropical cyclone bogus model after the relocation of the initial vortex in the background field. The relocation method of the initial vortex decreases the error caused by the deviation of the initial tropical cyclone location in tropical cyclone models. The relocation method is conducive to improving the track forecast of tropical cyclone models and has a good perspective for operational application. [ABSTRACT FROM AUTHOR]

We study the solution of neutral delay differential equations (NDDEs) by using boundary value methods (BVMs). The BVMs require the solution of nonsymmetric, large and sparse linear systems. The GMRES method with Strang-type block-circulant preconditioner is proposed to solve these linear systems. We show that, if an -stable BVM is used for solving a system of NDDEs, then our preconditioner is invertible and the spectrum of the preconditioned system is clustered. It follows that, when the GMRES method is applied to the preconditioned systems, the method can converge rapidly. Numerical results are given to show that our method is effective. [ABSTRACT FROM AUTHOR]

Background: Misuse and overuse of antibiotics by physicians in the treatment of children is common in China. This study aimed to reveal the overall use of antibiotics to treat children hospitalized in four types of pediatric wards.Methods: Seven independent point prevalence surveys (PPSs) were conducted in Shanghai Children's Hospital of Shanghai Jiao Tong University over the period 2012 to 2018. Pediatric ward types were defined general pediatric medical, pediatric surgical, pediatric intensive care units (PICU), and neonatal.Results: A total of 3975 pediatric patients were included in the study, of which 63.9% received at least one dose antibiotic. The top five classes of antibiotics administered were cephalosporins (43.8%, n = 1743), penicillins (13.2%, n = 526), carbapenems (8.7%, n = 347), nitroimidazoles (7.1%, n = 281) and macrolides (6.5%, n = 257). The five most commonly used generic antibiotics were cefuroxime (14.9%, n = 594), ceftriaxone (9.7%, n = 387), cefotaxime (9.0%, n = 358), meropenem (8.1%, n = 320) and ampicillin/sulbactam (6.0%, n = 239). Meropenem was among top five antibiotics prescribed in the general pediatric, PICU and neonatal wards and sixth in the pediatric surgical wards. Of all children on antibiotics, 23.4% received prophylactic treatment, and prophylaxis accounted for 68.1% of indications for treatment in the pediatric surgical wards.Conclusions: Given that over-treatment with third-generation cephalosporins and carbapenems has been associated with treatment-resistant infections, the prescription of these drugs should be strictly controlled and monitored, and measures should be taken to improve the management of surgical prophylaxis in hospitalized children in China. [ABSTRACT FROM AUTHOR]

Avian infectious bronchitis virus (IBV) is the causative agent of infectious bronchitis, which results in considerable economic losses. It is imperative to develop safe and efficient candidate vaccines to control IBV infection. In the current study, recombinant baculoviruses co-expressing the S1 and N proteins and mono-expressing S1 or N proteins of the GX-YL5 strain of IBV were constructed and prepared into subunit vaccines rHBM-S1-N, rHBM-S1 and rHBM-N. The levels of immune protection of these subunit vaccines were evaluated by inoculating specific pathogen-free (SPF) chickens at 14 days of age, giving them a booster with the same dose 14 days later and challenging them with a virulent GX-YL5 strain of IBV 14 days post-booster (dpb). The commercial vaccine strain H120 was used as a control. The IBV-specific antibody levels, as well as the percentages of CD4+ and CD8+ T lymphocytes, were detected within 28 days post-vaccination (dpv). The morbidity, mortality and re-isolation of the virus from the tracheas and kidneys of challenged birds were evaluated at five days post-challenge (dpc). The results showed that the IBV-specific antibody levels and the percentages of CD4+ and CD8+ T lymphocytes were higher in the rHBM-S1-N vaccinated birds compared to birds vaccinated with the rHBM-S1 and rHBM-N vaccines. At 5 dpc, the mortality, morbidity and virus re-isolation rate of the birds vaccinated with the rHBM-S1-N vaccine were slightly higher than those vaccinated with the H120 control vaccine but were lower than those vaccinated with the rHBM-S1 and rHBM-N vaccines. The present study demonstrated that the protection of the recombinant baculovirus co-expressing S1 and N proteins was better than that of recombinant baculoviruses mono-expressing the S1 or N protein. Thus, the recombinant baculovirus co-expressing S1 and N proteins could serve as a potential IBV vaccine and this demonstrates that the bivalent subunit vaccine including the S1 and N proteins might be a strategy for the development of an IBV subunit vaccine. [ABSTRACT FROM AUTHOR]