Optimization of Extraction Conditions for Total Flavonoids from Fructus Aurantii Immaturus and Its Anti-UVB Radiation Activity

[Objectives]Optimum extraction conditions of total flavonoids from Fructus Aurantii Immaturus(TFFAI)and its resistance activity to ultraviolet radiation were investigated in present research.[Methods]The optimal extraction conditions of TFFAI were determined by single factor and orthogonal experiments,and the survival rate of TFFAI on HaCaT cells irradiated with UVB rays was investigated.It s antioxidant capacity was determined by ABTS.[Results]The results showed that the highest yield of TFFAI was obtained with 70%ethanol at a solid-to-liquid ratio of 1:50(w/v)and 40℃for 1.5 h by single-factor and orthogonal experiments.Total flavonoids(0.25-1.00 mg/ml)could significantly improve the survival rate of HaCaT cell line.Meanwhile,the maximum absorption peak of TFFAI was found at 283 nm,and in-vitro antioxidant experiment identified that TFFAI had a good clearance rate to ABTS.It suggestes that TFFAI could protect the cells from UVB damage by absorption of UVB rays and anti-oxidation.[Conclusions]TFFAI played a protective role on UVB irradiated cells through UVB ultraviolet absorption and antioxidant pathways.

Mixed convectional and chemical reactive flow of nanofluid with slanted MHD on moving permeable stretching/shrinking sheet through nonlinear radiation,energy omission

Hybrid nanofluids are remarkable functioning liquids that are intended to reduce the energy loss while maximizing the heat transmission.In the involvement of suction and nonlinear thermal radiation effects,this study attempted to explore the energy transmission features of the inclined magnetohydrodynamic(MHD)stagnation flow of CNTs-hybrid nanofluid across the nonlinear permeable stretching or shrinking sheet.This work also included some noteworthy features like chemical reactions,variable molecular diffusivity,quadratic convection,viscous dissipation,velocity slip and heat omission assessment.Employing appropriate similarity components,the model equations were modified to ODEs and computed by using the HAM technique.The impact of various relevant flow characteristics on movement,heat and concentration profiles was investigated and plotted on a graph.Considering various model factors,the significance of drag friction,heat and mass transfer rate were also computed in tabular and graphical form.This leads to the conclusion that such factors have a considerable impact on the dynamics of fluid as well as other engineering measurements of interest.Furthermore,viscous forces are dominated by increasing the values ofλ_(p),δ_(m)andδ_(q),and as a result,F(ξ)accelerates while the opposite trend is observed for M andφ.The drag friction is boosted by the augmentation M,λ_(p)andφ,but the rate of heat transfer declined.According to our findings,hybrid nanoliquid effects dominate that of ordinary nanofluid in terms of F(ξ),Θ(ξ)andφ(ξ)profiles.The HAM and the numerical technique(shooting method)were found to be in good agreement.

Heat transfer and nanofluid flow over a porous plate with radiation and slip boundary conditions

Presence of different terms with various values can alter the thermal behavior of the nanofluids flow over porous surfaces.The aim of this research is to study the influence of nanoparticles volume fraction,nanoparticles type,suction or injection,the heat generation or absorption,the Eckert number,thermal and velocity slip parameters,and radiation on the velocity and temperature fields on the flow and heat transfer over a porous flat plate.Four different types of nanoparticles including metal nanoparticles (Cu),metal oxide nanoparticles (Al2O3) and carbon-based nanomaterials (MWCNTs and SWCNTs) which were dispersed in the water (as based fluid) are studied.The governing equations are converted into the ordinary differential equations using similarity solution and solved numerically by the RKF45 algorithm.The results of the simulations showed a contradiction with the results of other researchers who expressed that using nanoparticles with higher thermal conductivity and volume fraction led to increasing heat transfer rate in nanofluids;this study proves that,in some cases,boosting the volume fraction of nanoparticles has a potential to decrease the heat transfer rate due to significant changes in values of some parameters including radiation,heat generation,and viscous dissipation.

On Radiation Boundary Conditions and Wave Transformation Across the Surf Zone

The purpose of this paper is to extend the validity of Li's parabolic model (1994) by incorporating a combined energy factor in the mild-slope equation and by improving the traditional radiation boundary conditions. With wave breaking and energy dissipation expressed in a direct form in the equation, the proposed model could provide an efficient numerical scheme and accurate predictions of wave transformation across the surf zone. The radiation boundary conditions are iterated in the model without use of approximations. The numerical predictions for wave height distributions across the surf zone are compared with experimental data over typical beach profiles. In addition, tests of waves scattering around a circular pile show that the proposed model could also provide reasonable improvement on the radiation boundary conditions for large incident angles of waves.

Effects of UV-B radiation and different light repair conditions on the early development of the tetraspores of Chondrus ocellatus Holm

The effects of exposure to UV-B radiation, 280-315 nm, and dark or dark repair conditions on the early development of Chondrus ocellatus Holm collected from Qingdao coast were studied under the laboratory condition. After being exposed to different doses [0, 36, 72, 108, 144 and 180 J/（m2.d）] of UV-B radiation, one treatment of tetraspores were put back to normal culture condition （PAR）, the other treatment were put into dark condition to repair for 2 h. During the cultivation, the diameter of the tetraspores were recorded every 4 d till the 50th day when vertical branches formed in all treatments. Then at the 50th day, CPDs, phycoerythrin, chlorophyll a and MAAs （Palythine and asterina-330） were measured. The results showed that low doses UV-B radiation could significantly accelerate the growth rate of the rate reduced gradually with UV-B radiation keep on tetraspores of C. ocellatus and the growth increasing. The variation trend of both the phycoerythrin and chlorophyll a concentration reduced significantly （P 〈0.05） once given the UV- B radiation. Under UV-B stress, the CPDs were induced, and the concentrations of CPDs were significant low in dark repair groups. The data of MAAs analyzed by LC/MS in the tetraspores of C. ocellatus suggested that there were two MAAs formed （palythine and asterina-330） after UV-B radiation induced, and low dose of UV-B irradiation could significantly induced the concentration of MAAs. From the growth and development state of the tetraspores, negative effects of UV-B radiation on the dark repair groups were more serious than PAR.

Peristaltic flow with convective mass condition and thermal radiation

The primary objective of present investigation is to introduce the novel aspects of convective mass condition and thermal radiation in the peristaltic transport of fluid. Magnetohydrodynamic(MHD) fluid was considered in a symmetric channel. Heat and mass transfer characteristics were analyzed in the presence of Soret and Dufour effects, and the results were presented via two forms of thermal radiation. The temperature, concentration and pressure rise per wavelength were examined. It is observed that the velocity slip and magnetic field parameters have opposite effects on the pressure rise per wavelength. Temperature of fluid is a decreasing function of the radiation parameter. Further, the temperature of fluid decreases by increasing the heat transfer Biot number. It is notified that the heat transfer rate at the wall is a decreasing function of radiation parameter.

Unsteady MHD Mixed Convection Flow with Slip of a Nanofluid in the Stagnation Region of an Impulsively Rotating Sphere with Effects of Thermal Radiation and Convective Boundary Conditions

Unsteady magnetohydrodynamic mixed convection flow of an electrically conducting nanofluid in a stagnation region of a rotating sphere is studied numerically in the present article. Slip and convective boundary conditions are imposed to surface of the sphere and the thermal radiation effects are taken into account. The nanofluid is simulated using Buongiorno’s nanofluid model and the nanofluid particle fraction on the boundary is considered to be passively rather than actively controlled. Non-similar solutions are applied on the governing equations and the MATLAB function bvp4c is used to solve the resulting system. Effects of the key-parameters such as slip parameter, Biot number, radiation parameter, rotation parameter, Lewis number and Brownian motion parameter on the fluid flow, temperature and nanoparticle volume fraction characteristics are examined. Details of the numerical solution and a comprehensive discussion with the physical meaning for the obtained results are performed. The results indicated that the increase in slip parameter enhances the velocity profiles, while it decreases the temperature distributions. Also, the increase in either slip parameter or Biot number causes an improvement in the rate of heat transfer.

Nonlinear three-dimensional stretched flow of an Oldroyd-B fluid with convective condition, thermal radiation, and mixed convection

The effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed. The heat transfer phenomenon is explored by considering the non-linear thermal radiation and heat generation/absorption. The boundary layer as- sumptions are taken into account to govern the mathematical model of the flow analy- sis. Some suitable similarity variables are introduced to transform the partial differen- tial equations into ordinary differential systems. fifth-order techniques with the shooting method The Runge-Kutta-Fehlberg fourth- and are used to obtain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturbation solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tabulated and investigated. The enhancement in the values of the Deborah number shows a reverse behavior on the liquid velocities. The results show that the temperature and the thermal boundary layer are reduced when the non- linear convection parameter increases. The values of the Nusselt number are higher in the non-linear radiation situation than those in the linear radiation situation.

An Efficient Method for Local Base Transform in Pekeris Waveguide with Radiation Condition

In this paper, for the fast computation of the coordinates under the basis of the eigenfunctions of Helmholtz operator, we derive the conjugate operator with the radiation boundary condition. Further, we prove the cross orthogonality between the linearly-independent eigenfunctions of the Helmholtz operator and the linearly-independent eigenfunctions of the conjugate operator. The numerical simulations demonstrate the effectiveness of our treatment.

Statistical second-order two-scale analysis and computation for heat conduction problem with radiation boundary condition in porous materials

This paper discusses a statistical second-order two-scale（SSOTS） analysis and computation for a heat conduction problem with a radiation boundary condition in random porous materials.Firstly,the microscopic configuration for the structure with random distribution is briefly characterized.Secondly,the SSOTS formulae for computing the heat transfer problem are derived successively by means of the construction way for each cell.Then,the statistical prediction algorithm based on the proposed two-scale model is described in detail.Finally,some numerical experiments are proposed,which show that the SSOTS method developed in this paper is effective for predicting the heat transfer performance of porous materials and demonstrating its significant applications in actual engineering computation.

Significance of radiation esophagitis:Conditional survival assessment in patients with non-small cell lung cancer

Purpose:This study aimed to examine the effect of radiation esophagitis(RE)and the dynamics of RE on subse-quent survival in non-small cell lung cancer(NSCLC)patients who underwent radiotherapy.Experimental Design:Patients with NSCLC treated with fractionated thoracic radiotherapy enrolled in prospective trials were eligible.RE was graded prospectively according to Common Terminology Criteria for Adverse Events(CTCAE)v3.0 per protocol requirement weekly during-RT and 1 month after RT.This study applied conditional survival assessment which has advantage over traditional survival analysis as it assesses the survival from the event instead of from the baseline.P-value less than 0.05 was considered to be significant.The primary endpoint is overall survival.Results:A total of 177 patients were eligible,with a median follow-up of 5 years.The presence of RE,the maximum RE grade,the evolution of RE and the onset timing of RE events were all correlated with subsequent survival.At all conditional time points,patients first presented with RE grade1(initial RE1)had significant inferior subsequent survival(multivariable HRs median:1.63,all P-values<0.05);meanwhile those with RE progressed had significant inferior subsequent survival than those never develop RE(multivariable HRs median:2.08,all P-values<0.05).Multivariable Cox proportional-hazards analysis showed significantly higher C-indexes for models with inclusion of RE events than those without(all P-values<0.05).Conclusion:This study comprehensively evaluated the impact of RE with conditional survival assessment and demonstrated that RE is associated with inferior survival in NSCLC patients treated with RT.

Research on the Arrangement of Dew Point Temperature Detectors of Capillary Plane Radiation Air-Conditioning

Based on analysis of the reason and process of condensation on ceiling radiant cooling panels, two kinds of arrangement of detectors are put forward. The physical model is established, the results show that detectors are arranged as the form of triangle is more suitable. It can not only satisfy the use requirement but also it is economical and practical. Finally we can conclude that the inlet water temperature 0.5&deg;C higher than dew point temperature is safe and reliable.

Seismic analysis of dam-foundation-reservoir system including the effects of foundation mass and radiation damping

One of the main concerns in using commercial software for finite element analyses of dam-foundation-reservoir systems is that the simplifying assumptions of the massless foundation are unreliable. In this study, an appropriate direct finite element method is introduced for simulating the mass, radiation damping and wave propagation effect in foundations of damfoundation-reservoir systems using commercial software ABAQUS. The free-field boundary condition is used for modeling the semi-infinite foundation and radiation damping, which is not a built-in boundary condition in most of the available commercial software for finite element analysis of structures such as ANSYS or ABAQUS and thus needs to be implemented differently. The different mechanism for modeling of the foundation, earthquake input and far-field boundary condition is described. Implementation of the free-field boundary condition in finite element software is verified by comparing it with analytical results. To investigation the feasibility of the proposed method in dam-foundation-reservoir system analysis, a series of analyses is accomplished in a variety of cases and the obtained results are compared with the substructure method by using the EAGD-84 program. Finally, the massed and massless foundation results are compared and it is concluded that the massless foundation approach leads to the overestimation of the displacements and stresses within the dam body.

A CLIMATOLOGICAL STUDY ON SOLAR ULTRAVIOLET RADIATION

According to 2698 sets of observation data on solar direct radiation in sub-divisions of wave band at 10 spots of seven regions in China, the empirical formula and nomograph for estimating ultraviolet irradiance at wavelength λ< 400nm were obtained. Furthermore, a climatological method for estimating diffuse ultraviolet irradiance under various sky conditions was also developed based on radiation transmission equations. Using monthly mean daa at fixed time from eight stations, monthly mean daily totals of direct, diffuse and global ultraviolet radiations, as well as their fractions in the whole wave band were estimated respectively. Results show that the fraction of global ultraviolet radiation in the whole wave band is rather conservative, 5.5±0.4 Percent under clear sky condition, and 5.3±0.4 Percent under mean sky condition.

Dynamical Analysis of Radiation and Heat Transfer on MHD Second Grade Fluid

Convective flow is a self-sustained flow with the effect of the temperature gradient.The density is non-uniform due to the variation of temperature.The effect of the magnetic flux plays a major role in convective flow.The process of heat transfer is accompanied by a mass transfer process;for instance,condensation,evaporation,and chemical process.Due to the applications of the heat and mass transfer combined effects in a different field,the main aim of this paper is to do a comprehensive analysis of heat and mass transfer of MHD unsteady second-grade fluid in the presence of ramped boundary conditions near a porous surface.The dynamical analysis of heat transfer is based on classical differentiation with no memory effects.The non-dimensional form of the governing equations of the model is developed.These are solved by the classical integral(Laplace)transform technique/method with the convolution theorem and closed-form solutions are attained for temperature,concentration,and velocity.The physical aspects of distinct parameters are discussed via graph to see the influence on the fluid concentration,velocity,and temperature.Our results suggest that the velocity profile decrease by increasing the Prandtl number.The existence of a Prandtl number may reflect the control of the thickness of momentum and enlargement of thermal conductivity.Furthermore,to validate our results,some results are recovered from the literature.

Effect of UV Radiation and Other Abiotic Stress Factors on DNA of Different Wild Plant Species Grown in Three Successive Seasons in Alpine and Subalpine Regions

Plants in natural ecosystems are exposed to a combination of UV radiation,ionizing radiation(IR)and other abiotic factors.These factors change with the altitude.We investigated DNA alterations of some wild plants of different plant families in natural ecosystems at three altitudes in Rila Mountain,Bulgaria(1500,1782,and 2925 m above sea level(a.s.l.)exposed to UV radiation,IR and other abiotic stresses,to assess the tolerance of plant species to the changing environmental conditions in three successive growth seasons.For this purpose,physicochemical,cytogenetic,and molecular methods were applied.DNA damage was assessed by micronucleus test and molecular method comet assay adapted and applied by us to wild plant species from Onagraceae,Rosaceae,Boraginaceae,Saxifragaceae,Orobanchaceae,Asteraceae and Poaceae families,growing at three different altitudes.Variability in the DNA sensitivity and the level of tolerance was observed among the plant species in response to combined abiotic factors assessed by induced DNA damage and gross beta activity.The studied representatives of Poaceae were less susceptible than the other studied species at all three altitudes and showed close level of DNA injuries to that of unaffected control plant grown in laboratory conditions.The lower levels of DNA damage of these wild plant species corresponded to their lower ability to accumulate radionuclides.There was a particularly pronounced low level of DNA injuries in the plant species at the highest altitude.The level of DNA damage showed correlation with the values of some abiotic environmental factors.The results would contribute to the elucidation of the extent of adaptation of plant species to the continuously changing environment and would be useful in selecting sensitive herbaceous monitor species for environmental impact assessment at mountain and alpine sites.

Analysis of Solar Ultraviolet Radiation in Xilinhot

To further reveal the variation laws of ultraviolet radiation to provide better service for production and people＇s life, based on observation data of solar ultraviolet radiation obtained by Xilinhot National Climate Observatory in 2007-2012, the variation laws of solar ultraviolet radiation and its relationship with meteorological factors in different cloud conditions in Xilinhote were analyzed by using the mathematical and statistical methods and SPSS 11.5 software. The results showed that the solar ultraviolet radiation had obvious daily, seasonal and annual variations; the solar ultraviolet radiation was weak in the morning and evening but strong at noon; the maximum appeared from June to August, while the minimum appeared in November and December. It had significant correlation with total solar radiation, photosynthetically active radiation, air temperature, air humidity and ground temperature （0-5 cm）. At present, the maximum intensity of ultraviolet radiation （UV-B） was 0.20-1.91 W/m2 from January to March and 0.13-1.43 W/m2 from October to De- cember respectively, which were lower than the safety standard for people and animals （2 W/mZ）. However, the maximum might appear from April to September, ranging from 2.02 to 3.39 W/m2, which was easy to bring a threat and harm to people and animals.

Correlation Analyses between Ultraviolet Radiation, Global Solar Radiation, and Metrological Variables and the COVID-19 Cases in Arid Climate

The transmission of infectious diseases is influenced by several meteorological factors. In this study, the influence of several such factors in the transmission of COVID-19 (from 26 March 2020 to 29 July 2021) in the arid weather of Riyadh, Saudi Arabia was investigated using the Spearman and Kendall rank tests. The factors considered were the average, maximum, and minimum values of air temperatures, air pressure, wind speed, relative humidity, absolute humidity, dew point temperatures, and the average values of the global solar radiation and ultraviolet radiation at bands A and B. The data on meteorological factors were obtained from the King Abdulaziz City for Science and Technology (KACST) weather station, whereas the data on the daily COVID-19 cases were obtained from the official webpage of the Saudi Arabian Ministry of Health (MOH). The results revealed that air temperature (average, minimum, and maximum) average and maximum wind speed, maximum dew point temperature, global solar radiation, and ultraviolet radiation at A and B bands are positively associated with the daily number of COVID-19 cases reported in Riyadh. However, relative humidity, atmospheric pressure (averages, minimum, and maximum) is anti-correlated with the number of daily COVID-19 cases, while absolute humidity exerts no influence. These results are in total agreement with some of the previously established studies and are either contradicted partly or totally with others conducted at several locations around the world. The results could help not only epidemiologists understand the behavior of COVID-19 against meteorological variables but also national and international organizations and healthcare policymakers devise control strategies to combat the virus.

AN ADAPTIVE OPEN BOUNDARY CONDITION

A significant improvement of the open boundary condition which was originally studied by Engquist and Majda is given.The method given here is applicable without limitation of the angle between the direction of the incident wave and the normal to the boundary.It also improves the precision of the method from order one to two.The test examples show that this method is much better than the method mentioned above.

NUMERICAL AND EXPERIMENTAL STUDY OF THERMAL DISTRIBUTION INSIDE AIR-CONDITIONED AUTOMOBILE CHAMBER

A study of the fluid and temperature fields inside the air conditioned automobile chamber is carried out with numerical calculation. Combined with buoyancy, a k ε model is adopted to solve the turbulent flow in a typical air conditioned automobile chamber. During the calculation, the solar radiation energy is also considered by means of the Monte Carlo method. Human body is regarded as an important component during the calculation. To verify the numerical calculation, experiments have been carried out under a series of working conditions and the results are acceptable. In order to meet the demand of industrial engineering, software CAAC was provided with a convenient interface. Finally, most of the factors were analyzed to evaluate their importance.