Search

The sweet potato weevil (Cylas formicarius(Fab.) (Coleoptera: Brentidae)) is a pest that feeds on sweet potato (Ipomoea batatas(L.) Lam. (Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles (HIPVs) promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored. The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed viastable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of (Z)-3-hexenyl acetate (z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatasocimene synthase (IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate, (Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene, respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies.

Byline: Hai-Xing. Mai, Guo-Hui. Mei, Fei-Long. Zhao, Bo-Tao. Li, Yong-Yong. Tang, Bin. Zhang, Xiao-Jie. Xu, Li-Jun. Chen Objective: Sunitinib/sorafenib (SU/SO), dendritic cells (DCs), or DC-cytokine-induced killer (CIK) could significantly prolong [...]

Human epidermal growth factor receptor 2 (HER2) is a tumor biomarker with significant prognostic and therapeutic implications for invasive ductal breast carcinoma (IDC).

C13H16O6, monoclinic, P21/c(no. 14), a= 12.180(3) Å, b= 13.813(4) Å, c= 7.842(2) Å, β= 93.917(4)°, V= 1316.2(6) Å3, Z= 4, Rgt(F) = 0.0442, wRref(F2) = 0.1375, T = 296(2) K.

Here, we demonstrate a novel donor-intermediate-receptor energy transfer model through a Ce3+→ Tb3+→ Eu3+scheme in a CaTbAl3O7:Ce3+,Eu3+nanocrystalline phosphor. A new type of CaTbAl3O7and CaTbAl3O7:RE3+(RE3+= Ce3+and/or Eu3+) nanocrystalline phosphors were prepared by a simple sol–gel method. There exist efficient energy transfers of Ce3+→ Tb3+, Tb3+→ Eu3+, and Ce3+→ Tb3+→ Eu3+in CaTbAl3O7:RE 3+(RE 3+= Ce3+and/or Eu3+) nanocrystalline phosphors. With near-UV or UV light excitation, the as-prepared CaTbAl3O7:RE 3+(RE 3+= Ce3+and/or Eu3+) nanocrystalline phosphors’ luminous color can be regulated from green to green-yellow, yellow, orange, and orange-red by adjusting the doping concentration, categories, and different proportions of codoping Ce3+to Eu3+ions in the CaTbAl3O7matrix. The luminescence mechanism with respect to the CaTbAl3O7:RE3+(RE3+= Ce3+and/or Eu3+) nanocrystalline phosphors has been tentatively proposed. Due to their excellent luminescence properties, the as-prepared CaTbAl3O7, CaTbAl3O7:Ce3+, CaTbAl3O7:Eu3+, and CaTbAl3O7:Ce3+,Eu3+nanocrystalline phosphors exhibit bright prospects in NUV-LEDs and other photoelectric field.

Structured soft clays are widely distributed in the coastal regions of China. The characteristics of the natural structure greatly influence the compressibility and permeability of marine soft clays and should be considered in the theory of their consolidation. When a large surcharge load is applied to a structured clay deposit, large strains can be induced in the clay layer due to the high compressibility, where the consolidation process follows the large strain assumption. However, there are few published theories of consolidation in which both the natural structure of marine soft clays and the large strain assumption can be considered simultaneously. In this study, a novel large strain consolidation model for structured marine soft clays was developed by considering the variation of structural yield stress with depth and using different calculation methods for initial effective stress of structured clay deposits in the Lagrangian coordinate system. The corresponding solution was derived by the finite difference method. Finally, the influences of the natural structure of soft clays and different geometric assumptions on consolidation behavior were investigated. The results show that the dissipation rate of excess pore water pressure of structured clays under the large strain assumption is expected to be faster than that under the small strain assumption, and the difference in consolidation behavior between the two assumptions increases with the strain level of natural structured clays. If the strain level in the clay layer is more than 15%, the difference in consolidation behavior between the large and small strain assumptions must be considered.

In this study, Si and SiC powder with a critical particle size ranged from 0.1 to 0.4mm was added into MgO-C refractory as antioxidants. At 1200°C in air atmosphere, oxidation weight losses of cylindrical specimens with additives were measured and the effective diffusion coefficient of oxygen in refractories was calculated from the results. Thus, the effects of antioxidants particle size on the oxidation resistance were researched. The result shows that the particle size of antioxidant has a considerable influence on oxidation resistance of material. The oxidation resistance of MgO-C refractories increased at first as the critical particle size of Si powder increased from 0.1 to 0.2mm and then decreased as the critical particle size increased up to 0.4mm, while the oxidation resistance of MgO-C refractories decreased as the critical particle size of SiC additives increased from 0.1 to 0.4mm. The minimum effective diffusion coefficients of oxygen in MgO-C refractories added by Si and SiC were 10.90 and 14.09cm2/min, individually.

C14H16O5, triclinic, P1‾$‾{1}$(no. 2), a= 8.5293(8) Å, b= 11.5626(11) Å, c= 14.2196(13) Å, α= 88.888(10)°, β= 74.988(10)°, γ= 87.556(10)°, V= 1353.2(2) Å3, Z= 4, Rgt(F) = 0.0430, wRref(F2) = 0.1202, T= 296(2) K.

AbstractSample-time errors can greatly degrade the dynamic range of a time-interleaved sampling system. In this paper, a novel correction technique employing a cubic spline interpolation is proposed for inter-channel sample-time error compensation. The cubic spline interpolation compensation filter is developed in the form of a finite-impulse response (FIR) filter structure. The correction method of the interpolation compensation filter coefficients is deduced. A 4GS/s two-channel, time-interleaved ADC prototype system has been implemented to evaluate the performance of the technique. The experimental results showed that the correction technique is effective to attenuate the spurious spurs and improve the dynamic performance of the system.

The cracking bending strength for steel-polypropylene hybrid fiber reinforced concrete (HFRC) had been studied based on experimental test. the inicial cracking strength achieve significant improvement compare to plain concrete, and the highest increase is 16.7%. There is a synergistic effect exist when steel fiber is 1.0% in volume or polypropylene fiber is 0.1% in volume, and the synergistic effect raise to vertex (1.043) when both of those two requirements are fulfilled.

Three different volume ratio steel fiber and polypropylene fiber were mixed into concrete matrix to study the hybrid effect of fibers. Cube HFRC specimens were tested under uniaxial and triaxial load. Hybrid effects on compressive strength of the results were analyzed and compared. It was founded that there were positive and negative effects in HFRC under compression. Positive hybrid effects of HFRC could be found when volume ratios of fiber (no less than 1.0% for steel fiber and 0.1% for polypropylene fiber) were added into HFRC.

In allusion to the status quo of deficient in evaluation theory and methods on the social risk of dam-break, this paper established 24 index systems for the evaluation of dam-break social risk composed by the dam-break hazard intensity, accident probability, hazard-affected body inherent vulnerability and disaster relief capacity. The quantitative calculation formula has also been put forward for evaluation indexes. In line with the Delphi method, a judgment matrix on the social risk caused by dam-break has been constructed, and has obtained the weight of each index by virtue of analytic hierarchy process. The results show the internal friction angle, the downstream main ditch longitudinal gradient, the current dam height and the monitoring & forecasting capacity are the key indicators that affect the social risks of dam-break. The results of this study help to further enhance and improve the technical level of risk evaluation for the tailings pond.

Frost resistance of low antifreeze design level hydraulic concrete was studied with Climate Simulation System. Three temperature of -17°C, -20°C, -30°C were chosen as the inner low temperature of concrete specimen during freezing-thawing. The properties of mass, dynamic elastic modulus, flexural strength and compressive strength of low antifreeze design level hydraulic concrete under different low temperature were compared. And the microscopic property of low antifreeze design level hydraulic concrete was observed by environmental scanning electron microscope (ESEM).

The dynamic risk of underground cavities after gas outburst in coal uncovering construction of hydropower station was emphatically analyzed. The tunnel construction conditions in Xiangjiaba hydropower station were taken as an example. Based on the computational fluid dynamics theory and gas outburst theory, this paper used the ANSYS CFX CFD code to model the gas diffusion after gas outburst. The space-time characteristics of underground cavities dynamic risk were analyzed. The results show that the danger area ranges of gas explosion and asphyxia reach respectively the maximum value at about 140s and 50s. The influence range and duration of the former are significantly higher than the latter. The direction of hazardous area movement is mainly consistent with the air flow direction. ANSYS CFX simulation can visually display dynamic risk of underground cavities, and has a good prospect in gas hazard prevention in hydraulic and hydroelectric engineering.

The method, using slope buckling safety factor to measure the degree of dam-break hazard, results in the unscientific conclusions of identical dam-break risk with respect to the desolate & uninhabited gobi desert and densely populated & highly economic-developed city. On the basis of vulnerability theory, a dam-break hazard vulnerability assessment index system, which comprehensively considering the inherent risks of dam-break and the intrinsic vulnerability of hazard-affected bodies, was established. The production of dam-break hazard-causing factor intensity, including the current dam height, reservoir capacity & downstream main ditch longitudinal, and accident probability by the Monte Carlo method is the inherent risk level of dam-break. The result by the multiplying physical exposure and the intrinsic vulnerability, including household fitness index & the emergency self-help index, as well as the disaster relief capacity is the hazard-affected body vulnerability. Results are contributable to further consummate the vulnerability risk assessment technology and the reliability of dam-break hazard.

MgO-C continuous temperature-measuring sensors for liquid steel were made of fused magnesia with different critical particle sizes from 0. 5 to 2. 0 mm, thus the effects what magnesia’s particle size affect sensors’ properties and lifetime were studied. The result shows that the MgO-C continuous temperature-measuring sensor has good aggression resistance to basic tundish powders and meets the requirement for response time of temperature measuring practice in tundish. The sensor’s service life, which is affected by multi-properties of material and operating environment, reached its maximum when the critical particle size of magnesia was 1. 0 mm. The average lifetime of sensors was 43 or 40 h when served for casting SPHC or Q195 steel.

A radar signal processing system characterizing high instantaneous dynamic range and low system latency is designed based on a specifically developed signal processing platform. Instantaneous dynamic range loss is a critical problem when digital signal processing is performed on fixed-point FPGAs. In this paper, the problem is well resolved by increasing the wordlength according to signal-to-noise ratio (SNR) gain of the algorithms through the data path. The distinctive software structure featuring parallel pipelined processing and “data flow drive” reduces the system latency to one coherent processing interval (CPI), which significantly improves the maximum tracking angular velocity of the monopulse tracking radar. Additionally, some important electronic counter-countermeasures (ECCM) are incorporated into this signal processing system.

The pulse description word (PDW) measurement method of digital channelized reconnaissance receiver was investigated. The parameter measurement flow of digital channelized reconnaissance receiver was introduced. The measurement methods of the instantaneous amplitude, the instantaneous frequency, the pulse width of wideband frequency modulated signal and the direction of arrival (DOA) were discussed in detail, which have been applied to reconnaissance receiver in ESM system successfully.

Through exploiting a modified focal-length function, two-dimensional metallic cylindrical focusing micromirrors (MCFMs) with different preset focal depths are designed. Rigorous electromagnetic theory and the boundary element method are applied to analyzing the focal characteristics, including the actual focal depth, the relative focal depth, the focal spot size and the diffraction efficiency. Through setting the preset focal depth to be positive or negative, numerical results reveal that the designed MCFMs can successfully modulate the optical field distribution to achieve a long axial focal depth or increased lateral resolution, respectively. In addition, due to the inherent achromatic aberration property of the metallic reflective system, the common long-focal-depth region of the designed MCFM under multiwavelength illumination is greatly enlarged, in comparison with a dielectrically cylindrical microlens. It is expected that the designed MCFMs should have many practical applications in micro optics systems.

Using a general focal-length function, two-dimensional long-focal-depth (LFD) metallic cylindrical focusing micromirrors (MCFMs) are designed and the focal performance is systematically investigated based on rigorous electromagnetic theory and the boundary element method. For a positive preset focal depth, simulation results reveal that the designed MCFMs still possess an LFD property and high lateral resolution even when the f-number is reduced to f/0.3. On the other hand, through setting the preset focal depth to be negative, increased lateral resolution is obtained, compared with the conventional MCFM. In addition, under multiwavelength illumination, a large common LFD region is demonstrated for the designed LFD MCFMs, which is due to the intrinsic achromatic property of reflective systems.

Shrinkage stress of cementitious materials will generate if the dry shrinkage is restrained in drought condition. Shrinkage stress has influence on crack resistance of cementitious materials. The dry shrinkage of cementitious materials in different relative humidity was studied with Climate Simulation System. The dry shrinkage change law of concrete in 20°C, 60% relative humidity for 500 days and in 20°C, 10% relative humidity for 180 days was compared. The relation between water loss rate and shrinkage rate of cementitious materials in drought condition was analyzed.

800x600 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} In this study a resonant column apparatus was used to obtain the shear modulus and damping ratio of the waste granular rubber and cement soil mixtures. Specimens were tested for different rubber contents and confining pressures. Experiments show that with the rubber increased, the damping ratio of the rubber and cement soil mixtures increases, dynamic modulus decreases. When the confining pressure increases, the shear modulus of rubber and cement soil mixtures increase gradualy, damping ratio increase slightly.

Orthogonal tests are designed for hybrid fiber reinforced concrete. Bending toughness of hybrid fiber reinforced concrete, with the substrate intensity C30, the quantity of the volume for the steel fiber dosage 0~1.5% and polypropylene fiber dosage 0~0.3%, are studied. The results show that the hybrid fibers significantly improve the toughness of the concrete matrix. When the dosage reaches to a certain number, the affection of fiber toughness is decreased. Based on the test results the best dosage of hybrid fibers which is the steel fiber 1% mixed with 0.1% polypropylene fiber is recommended.

The sural neurofasciocutaneous flap has been widely used for reconstruction of soft-tissue defects in the lower leg, ankle, and foot. It can provide a large amount of tissue without compromising the function of the leg. The authors report the applications of the free peroneal perforator–based sural neurofasciocutaneous flap.

Information extraction for space objects based on narrowband radars is still a hot spot in the field of automatic target recognition. The attitude stability of space objects can be determined by randomicity and periodicity detection for RCS series. In this paper, a nonparametric statistics theory called run test is adopted to perform randomicity detection. Autocorrelation function and cepstrum analysis are used to judge periodicity and estimate the rotate speed for rotary targets. What’s more, a novel method is proposed here for attitude stability determination according to the rule of posture angle altering. The experiments with real data indicate the effectiveness of the methods.

As any linear antennas can be considered to be comprised of a large number of dipole antenna, therefore the study of dipole antenna characteristics has a very important significance to the application of the general linear antennas. In this paper, Firstly, the radiation field of the dipole antenna is analyzed, and then the radiation field mathematic model of a specific structural antenna is established. The antenna is composed of two orthogonal half-wavelength dipoles, and the current phase of one dipole is advanced the other by 90°. According to the polarization theory of electromagnetic wave, the polarization of this antenna is discussed. The antenna pattern mathematical formula is deduced in horizontal and perpendicular plane, and the antenna pattern is given in graphics. Finally, a new method is introduced that the directivity of horizontal polarization component can be enhanced by increasing the number of antenna elements in the vertical plane, the simulation result show that this method not only enhance the energy of horizontal direction, but also restrain the radiation of other direction.

In cities, green infrastructure has been used to mitigate flood risk, improve water quality, and harvest precipitation as a water source. Effective maintenance of green infrastructure requires optimal irrigation of plant root systems during the prolonged drying period. Based on the measurement of soil moisture, various drip irrigation systems have been developed. Surface irrigation, however, has the disadvantage of loss of soil moisture through evaporation. In addition, the growth of plants is mainly dependent on subsurface soil moisture, especially within the root zones. Therefore, there is a need to develop an automatic system regulating soil moisture at different depths. In this study, an Arduino-based irrigation control system was developed to regulate the volumetric water contents of soil within a certain depth range. A one-dimensional soil column test was conducted to demonstrate its performance. The test results show that the system enabled the regulation of soil water content within the specified range (12–20%) with an error of 2%. The error was further minimized by recalibrating the upper limit of the system. This study provides an improved green infrastructure irrigation system to control the moisture distribution within the soil subsurface.

Based on the modified state-space self-tuning control (STC), a novel low-order tuner via the modified observer/Kalman filter identification (OKID) is proposed for stochastic fractional-order chaotic systems. The OKID method is a time-domain technique that identifies a discrete input-output map by using known input-output sampled data in the general coordinate form, through an extension of the eigensystem realization algorithm (ERA). First, the estimated system in the general coordinate based on the conventional OKID method is transformed to the one in an observer form to fit the state-space innovation form for the STC. Then, in stead of the conventional recursive least squares (RLS) identification algorithm used for STC, the Kalman filter as a parameter estimator with the state-space innovation form is presented for effectively estimating the time-varying parameters. Besides, taking the advantage of the digital redesign approach, the derivation of the current-output-based observer is proposed for the modified STC. As a result, the low-order state-space self-tuner with the high-gain controller property is then proposed for stochastic fractional-order chaotic systems, which the fractional operators are well approximated using the standard high integer-order operators. Finally, the fractional-order Chen and Roumlssler systems with stochastic system process and measurement noises are used as illustrative examples to demonstrate the effectiveness of the proposed methodology [ABSTRACT FROM PUBLISHER]

C8H6N2O1, monoclinic, P21/c(no. 14), a= 8.6277(17) Å, b= 13.134(3) Å, c= 13.062(5) Å, β= 110.54(3)°, V= 1386.0(7) Å3, Z= 8, Rgt(F) = 0.0512, wRref(F2) = 0.1581, T= 293(2) K.

C10H10N1O4S1Na, monoclinic, P21/c, a= 16.737(3) Å, b= 6.6610(13) Å, c= 10.427(2) Å, β= 97.69(3)°, V= 1152.0(4) Å3, Z= 4, Rgt(F) = 0.0419, wRref(F2) = 0.1104, T= 293(2) K.

Abstract: To investigate the changes of trace elements in the hair of Rhesus monkeys with esophageal precancerous lesions from Taihang Mountain. Methods: The quantities of trace and other elements including Cu, Zn, Fe, Mn in the hair of Rhesus monkeys were determined using atomic absorption spectrophotometry. Results: Compared with normal subjects, Fe content is remarkably higher in the cases of esophageal epithelium proliferation (P<0.01), and Cu content is significantly higher in those with high proliferation (P<0.05); The results showed no marked difference in the quantities of Zn and Mn between the cases and the normal (P>0.05). Conclusion: the present study may provide some basic information foundation for the study of the human esophageal cancer.