Study on Epidemic Characteristics and Its Causes of Wheat Stripe Rust in Nanchong City

On basis of the research result of stripe rust for 16 years since 1999,the epidemic characteristics and trend of stripe rust in the city were determined.Namely,the earlier the initial stage appeared,the heavier the disease would be.Furthermore,stripe rust has two introduction infection peaks,of which the first peak plays a key role.In farmlands,there are one to three epidemic peaks,and the infection area of the first peak plays the key role on the epidemic area of that year.In addition,the accumulated areas of late January was in significantly positive correlation with annually total area,with a correlation coefficient of 0.769 2.In recent 16 years,the frequency of severe stripe rust was as high as 81.25% which was 50% higher than that before 1995.The slight stripe rust became just in 2013,with a frequency of 6.3%,which indicated that the city has become a region hit by severe stripe rust.The internal reason is the reduction or loss of wheat variety＇s resistance to tripe rust for a new physiological race of rust is becoming pathogenic stronger and be the major race.Big fluctuation of temperatures in warm winter and spring,foggy and dew days slants much would be the external reason.

Relationship Between H^+-ATPase Activity and Fluidity of Tonoplast in Barley Roots Under NaCl Stress

H +_ATPase activity of tonoplast in roots of Hordeum vulgare L. cv. 'Tanyin 2' (salt_tolerant cultivar) increased when the roots were exposed to 50-200 mmol/L NaCl for 2 d, and decreased when NaCl concentration was increased to 600 mmol/L. In 'Kepin 7' (salt_sensitive cultivar), tonoplast H +_ATPase activity in roots also increased at lower levels of NaCl (50-100 mmol/L), but decreased at higher levels of NaCl (200-600 mmol/L). Tonoplast fluidity in roots of 'Tanyin 2' decreased at 50-200 mmol/L NaCl, and increased significantly at 600 mmol/L NaCl. Under salt stress, the change of tonoplast fluidity was identical with that of the ratio of unsaturated fatty acids to saturated fatty acids in tonoplast lipid of barley roots. It is proposed that the increase of tonoplast fluidity due to increased degree of unsaturation of fatty acids is one of the reasons leading to the decrease of H +_ATPase activity under higher level of NaCl stress.

Ammonia Volatilization from Winter Wheat Field Top Dressed with Urea

Ammonia volatilization was measured with a continuous air flow enclosure method from a winter wheat field in the Experimental Farm of Jurong Agricultural School to investigate its main influencing factors. The experiment with five treatments in triplicate, no N (control), 100, 200 and 300 kg N ha-1 with rice straw cover at a rate of 1500 kg ha-1 and 200 kg N ha-1 without rice straw, started when the winter wheat was sown in 1994. Sixty percent of the total amount of N applied was hasal and 40% was top-dressed. The measurement of ammonia volatilization was immediately conducted after urea was top-dressed on soil surface at wheat elongation stage in spring of 1996 and 1997. The results showed that there was a diurnal variation of ammonia volatilization rate from the winter wheat field, which synchronized with air temperature. N losses through ammonia volatilization increased with increasing N application rate, but the ratio of N lost through ammonia volatilization to applied N was not significantly affected by N application rate. The coverage of rice straw had no significant effect on ammonia volatilization. Soil moisture and rain events after urea was top-dressed affected ammonia volatilization significantly.

Convective heat and mass transfer effects in three-dimensional flow of Maxwell fluid over a stretching surface with heat source

Heat and mass transfer effects in three-dimensional flow of Maxwell fluid over a stretching surface were addressed.Analysis was performed in the presence of internal heat generation/absorption. Concentration and thermal buoyancy effects were accounted. Convective boundary conditions for heat and mass transfer analysis were explored. Series solutions of the resulting problem were developed. Effects of mixed convection, internal heat generation/absorption parameter and Biot numbers on the dimensionless velocity, temperature and concentration distributions were illustrated graphically. Numerical values of local Nusselt and Sherwood numbers were obtained and analyzed for all the physical parameters. It is found that both thermal and concentration boundary layer thicknesses are decreasing functions of stretching ratio. Variations of mixed convection parameter and concentration buoyancy parameter on the velocity profiles and associated boundary layer thicknesses are enhanced. Velocity profiles and temperature increase in the case of internal heat generation while they reduce for heat absorption. Heat transfer Biot number increases the thermal boundary layer thickness and temperature. Also concentration and its associated boundary layer are enhanced with an increase in mass transfer Biot number. The local Nusselt and Sherwood numbers have quite similar behaviors for increasing values of mixed convection parameter, concentration buoyancy parameter and Deborah number.

Gaseous Loss of Nitrogen from Fertilizers Applied to Wheat on a Calcareous Soil in North China Plain

Nitrogen (N) losses from ammonium bicarbonate or urea applied to wheat and then followed immediately by irrigation were investigated. Ammonia volatilization was determined by a micrometeorological method (ammonia sampler), total N loss was estimated by the 15N mass balance method, and denitrification loss was measured by the difference method (calculated from the difference between the total N loss and ammonia loss)and a direct method (measuring the emission of (N2+N2O)-15N ). Total ammonia losses from ammonium bicarbonate and urea in 33 days were 8.7% and 0.9% of the applied nitrogen, respectively. The corresponding total N losses were 21.6% and 29.5%. Apparent denitrification losses (by the difference method) were rather high, being 12.9% from ammonium bicarbonate and 28.6% from urea. However, no emission of (N2+N2O)-15N was detected using the direct method.

Postharvest Losses in the Wheat Logistics Chain： A Brazilian Case Study

This paper highlighted the losses occurring along the wheat supply chain in Rio Grande do Sul （RS）, Brazil, which accounts for almost half of the domestic wheat production. Based on a field research, a questionnaire was applied to representative agents in the market. Then the wheat supply chain in the state of RS was characterized and loss rates in each stage of that chain were quantified. Typically, losses during transportation in the domestic market account for about 11.8% of the total amount of wheat grain that leaves the farms. Losses during harvest and storage in cooperatives, which account for 93.2% of total losses, stand out in this context. Transportation operations account for 6.8% of total losses in the analyzed flow. Based on the results obtained in this study, strategies are suggested to reduce food losses in different links of the logistics chain, such as to evidence and quantify the wheat losses, to manage losses and set reduction targets and to give attention to transportation service levels.

Series Solution for Rotating Flow of an Upper Convected Maxwell Fluid over a Stretching Sheet

The equations for two-dimensional flow of an upper convected Maxwell （UCM） fluid in a rotating frame are modeled. The resulting equations are first simplified by a boundary layer approach and then solved by a homotopy analysis method （HAM）. Convergence of series solution is discussed through residual error curves. The results of the influence of viscoelastic and rotation parameters are plotted and discussed.

Reflections on Islam and Co-Existence in the Upper Cross River Region of Nigeria

Situated within the Cross River State of Nigeria, the Upper Cross River area covers the northern half of Cross River State comprising Ugep, Obubra, Ikom, Ogoja, and Obudu divisions. Bounded on the north by the Benue region, west by Ebonyi and Enugu states and east by the Republic of Cameroon, this unique area experienced colonial rule. Christianity established its dominance in this area during colonial times, leaving no room for Islam. However, following the 1967 to 1970 civil war, groups of Islamic traders, clerics, and businessmen started trickling into the area, and settling there. They began to spread their faith in the region hut could not establish their political presence there. Some familiarised themselves with the culture of the indigenous people, and won converts not by force, but via the proselytisation of their faith. Community leaders did not abandon the old verities which bound traditional society in the region together. The pattern was often a pragmatic choice--accepting the best of the faiths resulting in peaceful co-existence and assured social harmony in the region. Pockets of Islamic converts could be found in Ogoja, Obudu, and some strategic commercial locations in the region. Against this backdrop, the paper examines the co-existence of Islam in the Upper Cross River Region （UCRR） and the impact made economically, culturally and religiously on the peoples of the region. The research adopted secondary and primary sources of information in its methodology. It therefore established that the UCRR of Nigeria serves as an excellent example, or a convenient model for the study of mutual religious co-existence between adherents of the Islamic and other faiths in the region.

Temporal and Spatial Distribution Patterns of Grain Crops in the West Liaohe River Basin

Here,we quantitatively determine temporal and spatial distribution characteristics of main grain crops in the West Liaohe River basin,Inner Mongolia,China,from 2000 to 2010 based on MODIS remote sensing data and NDVI time series information for the years 2000,2005 and 2010.Phenological calendars and a decisionmaking tree extraction model were also used to obtain spatial distribution information of spring maize,spring wheat and soybean.We found that in 2010,the sown area of the main grain crops in the West Liaohe River basin was 11 965.08km2,of which,the sown area for spring maize accounted for 92.28%and was concentrated in the lower reaches of the region.Spring wheat accounted for 3.14% and was mainly in the middle reaches.Soybean accounted for 4.58% and was predominantly in the upper reaches.From 2000 to 2005,the sown area of these grain crops in the West Liaohe River basin grew by 29.77%,mainly in the lower reaches： spring maize grew by 38.99%,spring wheat by 39.04% and soybean by 21.27%.From 2005 to 2010,growth in the sown area of these crops was slow（5.18% growth） and mainly in the lower reaches of the basin.The sown area of spring maize increased,but decreased for both spring wheat and soybean.

f(R) gravity and Maxwell equations from the holographic principle

Extending the holographic program of our previous work,we derive f(R) gravity and the Maxwell equations from the holographic principle,using time-like holographic screens.We find that to derive the Einstein equations and f(R) gravity by a natural holographic approach,the quasi-static condition is necessary.We also find the surface stress tensor and the surface electric current,surface magnetic current on a holographic screen for f(R) gravity and Maxwell's theory,respectively.

Influence of Non-linear Radiation Heat Flux on Rotating Maxwell Fluid over a Deformable Surface: A Numerical Study

Mathematical model for Maxwell fluid flow in rotating frame induced by an isothermal stretching wall is explored numerically. Scale analysis based boundary layer approximations are applied to simplify the conservation relations which are later converted to similar forms via appropriate substitutions. A numerical approach is utilized to derive similarity solutions for broad range of Deborah number. The results predict that velocity distributions are inversely proportional to the stress relaxation time. This outcome is different from that observed for the elastic parameter of second grade fluid. Unlike non-rotating frame, the solution curves are oscillatory decaying functions of similarity variable. As angular velocity enlarges, temperature rises and significant drop in the heat transfer coefficient occurs. We note that the wall slope of temperature has an asymptotically decaying profile against the wall to ambient ratio parameter. From the qualitative view point, temperature ratio parameter and radiation parameter have similar effect on the thermal boundary layer. Furthermore, radiation parameter has a definite role in improving the cooling process of the stretching boundary.A comparative study of current numerical computations and those from the existing studies is also presented in a limiting case. To our knowledge, the phenomenon of non-linear radiation in rotating viscoelastic flow due to linearly stretched plate is just modeled here.

Simulation of the stratospheric gravity waves generated by the Typhoon Matsa in 2005

The generation of stratospheric gravity waves （GWs） due to typhoon is simulated by using a meso-scale model （WRF） with a typhoon case, the Matsa in 2005. An 8-day model run that covers the major stages of the Matsa＇s development reproduces the key features of the typhoon. For example, good agreements in the typhoon＇s track, the intensity, and the spiral clouds, as well as mean state of stratosphere, are seen between the simulation results and the observation. Simulation results clearly show that with typhoon propagates northwestward, pronounced stratospheric GWs are generated continuously in the vicinity of Matsa. The GWs exhibit the typical curve-like wave fronts away from the Typhoon Matsa, and propagate preferentially in the up- stream of the background winds. These characteristics reflect that the stratospheric GWs are closely associated with the ty- phoon, and thus the GWs are referred to as Tropical Cyclone related Gravity Waves （TC-GWs）. The results also show that these waves should have a rather large horizontal scale so that the outmost wave fronts can be seen at the distance of ~ 1000 km to the typhoon center in the horizontal plane of 20 kin. This is consistent with the phenomenon of stratospheric TC-GWs with 1000 km horizontal scale disclosed by the previous observational analysis results.

Time Periodic Electroosmotic Flow of The Generalized Maxwell Fluids in a Semicircular Microchannel

Analytical solutions are presented using method of separation of variables for the time periodic electroosmotic flow (EOF) of linear viscoelastic fluids in semicircular microchannel. The linear viscoelastic fluids used here are described by the general Maxwell model. The solution involves analytically solving the linearized Poisson-Boltzmann (P -B) equation, together with the Cauchy momentum equation and the general Maxwell constitutive equation. By numerical computations, the influences of electric oscillating Reynolds number Re and Deborah number De on velocity amplitude are presented. For small Re, results show that the larger velocity amplitude is confined to the region near the charged wall when De is small. With the increase of the Deborah number De, the velocity far away the charged wall becomes larger for large Deborah number De. However, for larger Re, the oscillating characteristic of the velocity amplitude occurs and becomes significant with the increase of De, especially for larger Deborah number.

Influence of Non-Maxwellian Particles on Dust Acoustic Waves in a Dusty Magnetized Plasma

In this paper an investigation into dust acoustic sofitary waves （DASWs） in the presence of superthermM electrons and ions in a magnetized plasma with cold dust gains and trapped electrons is discussed. The dynamic of both electrons and ions is simulated by the generalized Lorentzian （κ） distribution function （DF）. The dust grains are cold and their dynamics are studied by hydrodynamic equations. The basic set of fluid equations is reduced to modified Korteweg-de Vries （mKdV） equation using Reductive Perturbation Theory （RPT）. Two types of solitary waves, fast and slow dust acoustic soliton （DAS） exist in this plasma. Caiculations reveal that compressive solitary structures are possibly propagated in the plasma where dust grains are negatively （or positively） charged. The properties of DASs are also investigated numerically.

Large Amplitude Dust Ion Acoustic Solitons and Double Layers in Dusty Plasmas with Ion Streaming and High-Energy Tail Electron Distribution

Large amplitude dust ion acoustic （DIA） solitons as well as double layers （DLs） are studied in a dusty plasma having a high-energy-tail electron distribution. The influence of electron deviation from the Maxwellian distribution and ion streaming on the existence domain of solitons is discussed in the （M, f） space using the pseudo-potential approach. It is found that in the presence of streaming ions and for a fixed f, solitons may appear for larger values of M. This means that in the presence of ion streaming, high values of the Mach number are needed to have soliton. The DIA solitary waves profile is highly sensitive to the ion streaming speed. Their amplitude is found to decrease with an increase of the ion streaming speed. In addition, we find that the ion streaming effect may lead to the appearance of double layers. The results of this axticle should be useful in understanding the basic nonlinear features of DIA waves propagating in space dusty plasmas, especially those including a relative motion between species, such as comet tails and solar wind streams, etc.