Design and selection of an artificial diet for the coconut black-headed caterpillar, Opisina arenosella, based on orthogonal array analysis

Opisina arenosella has been an outbreak pest of coconut trees in southern China since 2013. To develop efficient control methods for this invasive pest, adequate rearing protocols are desirable. In this study, an orthogonal array of artificial diets with 11 factors at 3 levels was deployed for both 2 nd–4 th and 5 th–6 th instar larvae of O. arenosella. Biological parameters including survival time of larvae, development time from larva to pupa, pupation rate, emergence rate, and pupal weight were monitored to reveal the most important components in the diet formulas. Biological parameters in O. arenosella were most affected by brewer’s yeast, sucrose, ascorbic acid, and wheat germ. Statistical analysis indicated that different diet combinations supported optimum performance of biological parameters for 2 nd–4 th and 5 th–6 th instar larvae. The validity of the optimization predicted by the orthogonal array analysis was confirmed in a follow-up bioassay with similar optimized diets for both 2 nd–4 th and 5 th–6 th instar larvae. The optimal artificial diet has great potential for the mass rearing technique, and can provide valuable results for using parasitoids in biological control of O. arenosella.

Analysis of the regional spectral properties in northwestern South China Sea based on an empirical orthogonal function

This study presents an analysis of the spectral characteristics of remote sensing reflectance(Rrs)in northwestern South China Sea based on the in situ optical and water quality data for August 2018.Rrswas initially divided into four classes,classes A to D,using the max-classification algorithm,and the spectral properties of whole Rrs were characterized using the empirical orthogonal function(EOF)analysis.Subsequently,the dominant factors in each EOF mode were determined.The results indicated that more than 95%of the variances of Rrs are partly driven by the back-scattering characteristics of the suspended matter.The initial two EOF modes were well correlated with the total suspended matter and back-scattering coefficient.Furthermore,the first EOF modes of the four classes of Rrs(A-D Rrs-EOF1)significantly contributed to the total variances of each Rrs class.In addition,the correlation coefficients between the amplitude factors of class A-D Rrs-EOF1 and the variances of the relevant water quality and optical parameters were better than those of the unclassified ones.The spectral shape of class ARrs-EOF1 was governed by the absorption characteristic of chlorophyll a and colored dissolved organic matter(CDOM).The spectral shape of class B Rrs-EOF1 was governed by the absorption characteristic of CDOM since it exhibited a high correlation with the absorption coefficient of CDOM(ag(λ)),whereas the spectral shape of class C Rrs-EOF1 was governed by the back-scattering characteristics but not affected by the suspended matter.The spectral shape of class D Rrs-EOF1 exhibited a relatively good correlation with all the water quality parameters,which played a significant role in deciding its spectral shape.

Orthogonal experiment investigation on wear resistance of MoSi2

The influence of lubricant conditions, wear loads, and counterparts on thefriction and wear characteristics of an MoSi_2 material was investigated by means of orthogonalanalysis. Orthogonal experiment results show that the order of influencing degree of the factors islubricant condition > load > counterpart. MoSi_2 has excellent friction-wear comprehensiveproperties against higher-hardness counterparts on the higher load and 20 oil lubricant conditions.

Targeted metabolomics study of fatty-acid metabolism in lean metabolic-associated fatty liver disease patients

BACKGROUND The annual incidence of metabolic-associated fatty liver disease(MAFLD)in China has been increasing and is often overlooked owing to its insidious charac-teristics.Approximately 50%of the patients have a normal weight or are not obese.They are said to have lean-type MAFLD,and few studies of such patients are available.Because MAFLD is associated with abnormal lipid metabolism,lipid-targeted metabolomics was used in this study to provide experimental evidence for early diagnosis and pathogenesis.MAFLD and analyze metabolic pathways.UPLC-Q-Orbitrap/MS content determination was used to determine serum palmitic acid(PA),oleic acid(OA),linoleic acid(LA),and arachidonic acid(AA)levels in lean-type MAFLD patients.RESULTS Urea nitrogen and uric acid levels were higher in lean-type MAFLD patients than in healthy individuals(P<0.05).Alanine transaminase and cholinesterase levels were higher in lean-type MAFLD patients than in healthy indi-viduals(P<0.01).The expression of high-density lipoprotein and apolipoprotein A-1 were lower in lean-type MAFLD patients than in healthy individuals(P<0.05)and the expression of triglycerides and fasting blood glucose were increased(P<0.01).A total of 65 biomarkers that affected the synthesis and metabolism of fatty acids were found with P<0.05 and variable importance in projection>1.The levels of PA,OA,LA,and AA were significantly increased compared with healthy individuals.CONCLUSION The metabolic profiles of lean-type MAFLD patients and healthy participants differed significantly,yielding 65 identified biomarkers.PA,OA,LA,and AA exhibited the most significant changes,offering valuable clinical guidance for prevention and treatment of lean-type MAFLD.

Spatio-temporal variability of surface chlorophyll a in the Yellow Sea and the East China Sea based on reconstructions of satellite data of 2001-2020

Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental monitoring.The spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)method.The reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day data.Chl-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early winter.By performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and summer.The increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring blooms.The high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a concentrations.The sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).

VIRTUAL EXPERIMENTAL ANALYSIS ON CLEANING ELEMENT OF SUGARCANE HARVESTER

The laws of influence of different factors have been analyzed in order to enhance the working efficiency and fatigue life of the cleaning element in brush shape of the sugarcane harvester. Based on the principle of orthogonal experiment design, the virtual-orthogonal-experimental analysis for the cleaning element is carried out on the finite element analysis （FEA） software-ANSYS after analyzing the nonlinear structural behavior in the working procedure. The results are analyzed with the overall balancing method, and then the optimal combination is got, which is made up of different levels of different factors. Also the optimal combination of design parameters of the cleaning element received fiom the virtual experimental analysis is conducted an experiment to confirm that the virtual analysis model and results are right, and the effect of factors on the function of the cleaning element is obtained by more analysis and further optimizing.

THE CONSTRUCTION OF ORTHOGONAL WAVELET BASIS ON[0,1] AND NUMERICAL SIMULATION

In this paper, we show the construction of orthogonal wavelet basis on the interval [0, 1],using compactly supportted Daubechies function. Forwardly, we suggest a kind of method to deal with the differential operator in view of numerical analysis and derive the appoximation algorithm of wavelet ba-sis and differential operator, which affects on the basis, to functions belonging to L2 [0, 1 ]. Numerical computation indicate the stability and effectiveness of the algorithm.

Microwave Technique for Polysaccharide Extraction from Dendrobium huoshanense

The effect of material granularity, extraction times, extraction time, mi-crowave power and solid-liquid ratio on the yield of polysaccharide of Dendrobium huoshanense in microwave-assisted extraction was discussed through single factor experiment. The key factors in polysaccharide extraction and the advantages over the traditional extraction method were studied based on orthogonal experiment. The results showed that the influences became unobvious with the promotion of the fac-tor’s level. The orthogonal experiment showed that the optimal factor in the mi-crowave-assisted extraction was that the sample was extracted for four times with an extraction time of 40 min under 550 W. Al these results would lay a founda-tion for exploring a new method for the extraction of polysaccharide from Dendrobi-um huoshanense.

The Interannual Variability of Summer Rainfall in the Arid and Semiarid Regions of Northern China and Its Association with the Northern Hemisphere Circumglobal Teleconnection

Using the latest daily observational rainfall datasets for the period 1961–2008, the present study investigates the interannual variability of June–September （JJAS） mean rainfall in northern China. The regional characteristics of JJAS mean rainfall are revealed by a rotated empirical orthogonal function （REOF） analysis. The analysis identifies three regions of large interannual variability of JJAS rainfall： North China （NC）, Northeast China （NEC）, and the Taklimakan Desert in Northwest China （TDNWC）. Summer rainfall over NC is shown to have displayed a remarkable dry period from the late 1990s; while over NEC, decadal-scale variation with a significant decreasing trend in the last two decades is found, and over TDNWC, evidence of large interannual variability is revealed. Results also show that the interannual variability of JJAS rainfall in northern China is closely associated with the Northern Hemisphere circumglobal teleconnection （CGT）. Correlation coefficients between the CGT index and regional-averaged JJAS mean rainfall over NC and NEC were calculated, revealing values of up to 0.50 and 0.53, respectively, both of which exceeded the 99% confidence level.

Anomaly feature of seasonal frozen soil variationson the Qinghai-Tibet Plateau

The seasonal frozen soil on the Qinghai-Tibet Plateau has strong response to climate change, and its freezing-thawing process also affects East Asia climate. In this paper, the freezing soil maximum depth of 46 stations covering 1961–1999 on the plateau is analyzed by rotated experience orthogonal function (REOF). The results show that there are four main frozen anomaly regions on the plateau, i.e., the northeastern, southeastern and southern parts of the plateau and Qaidam Basin. The freezing soil depths of the annual anomaly regions in the above representative stations show that there are different changing trends. The main trend, except for the Qaidam Basin, has been decreasing since the 1980s, a sign of the climate warming. Compared with the 1980s, on the average, the maximum soil depth decreased by about 0.02 m, 0.05 m and 0.14 m in the northeastern, southeastern and southern parts of the plateau, but increased by about 0.57 m in the Qaidam Basin during the 1990s. It means there are different responses to climate system in the above areas. The spectrum analysis reveals different change cycles: in higher frequency there is an about 2-year long cycle in Qaidam Basin and southern part of the plateau in the four representative areas whereas in lower frequency there is an about 14-year long cycle in all the four representative areas due to the combined influence of different soil textures and solutes in four areas.

Effect of welding parameters on Al/Ti joint property in electron beam welding-brazing

The electron beam welding-brazing being used to join 5A06 Al alloy to TC4 Ti alloy decreases the formation of brittle intermetallic compound.Experiments were carried out to study the influence of electron beam welding parameters on the tensile strength of welds,based on an orthogonal test and analysis method.The welding parameters include beam current,welding speed,scanning figure,scanning frequency,figure size,beam offset and focus current.The optimum parameters for3 mm 5A06 Al alloy and 2 mm TC4 alloy were as follows：acceleration voltage was 60 kV,beam current was 11 mA,welding speed was 600 mm/min,focus current was 0 mA,scan figure was O,scanning frequency was 1 000 Hz and beam offset was 0.5 mm.The results show that the joints were with good appearance and quality welded by the optimum parameters.The successful joints could be gained and the maximum tensile strength of Al/Ti dissimilar alloy joints could be up to 222.61 MPa using electron beam welding-brazing.

Bias correction of sea surface temperature retrospective forecasts in the South China Sea

Offline bias correction of numerical marine forecast products is an effective post-processing means to improve forecast accuracy. Two offline bias correction methods for sea surface temperature(SST) forecasts have been developed in this study: a backpropagation neural network(BPNN) algorithm, and a hybrid algorithm of empirical orthogonal function(EOF) analysis and BPNN(named EOF-BPNN). The performances of these two methods are validated using bias correction experiments implemented in the South China Sea(SCS), in which the target dataset is a six-year(2003–2008) daily mean time series of SST retrospective forecasts for one-day in advance, obtained from a regional ocean forecast and analysis system called the China Ocean Reanalysis(CORA),and the reference time series is the gridded satellite-based SST. The bias-correction results show that the two methods have similar good skills;however, the EOF-BPNN method is more than five times faster than the BPNN method. Before applying the bias correction, the basin-wide climatological error of the daily mean CORA SST retrospective forecasts in the SCS is up to-3°C;now, it is minimized substantially, falling within the error range(±0.5°C) of the satellite SST data.

Temporal-spatial oceanic variation in relation with the three typical Kuroshio paths south of Japan

Empirical orthogonal function(EOF)analysis was applied to a 50-year long time series of monthly mean positions of the Kuroshio path south of Japan from a regional reanalysis.Three leading EOF modes characterize the contributions from three typical paths of the Kuroshio meander:the typical large meander path,the offshore nonlarge meander path,and the nearshore non-large meander path,respectively.Accordingly,the spatial variation characteristics of oceanic anomaly fields can be depicted by their regression fields upon the associated three leading principal components(PCs),which are well-matched with the results of composite analysis corresponding to each period of the three typical Kuroshio paths.A new index for the typical large meander is defined by using the second leading PC,which is highly correlated with the Kushimoto-Uragami index.Spectral analysis of this new index series shows variability of the Kuroshio path south of Japan at time scales of about 7–8 years and 20 years.

Influence of tool pin profile and rotational speed on the formation of friction stir welding zone in AZ31 magnesium alloy

In this investigation,the effect of friction stir welding(FSW)parameters such as tool pin profiles,rotational speed and welding speed on the mechanical properties of tensile strength,hardness and impact energy of magnesium alloy AZ31 was studied.The experiments were carried out as per Taguchi parametric design concepts and an L9 orthogonal array was used to study the influence of various combinations of process parameters.Statistical optimization technique,ANOVA,was used to determine the optimum levels and to find the significance of each process parameter.The results indicate that rotational speed(RS)and transverse speed(TS)are the most significant factors,followed by tool pin profile(PF),in deciding the mechanical properties of friction stir welded magnesium alloy.In addition,mathematical models were developed to establish relationship between different process variables and mechanical properties.

Optimization of parameters and study of joint microstructure of resistance spot welding of magnesium alloy

Experimental investigations on the DC spot welding of Mg alloy AZ31B are presented. Experiments are carried out to study the influence of spot welding parameters （ electrode force, welding heat input and welding time） on the tensile shear load and the diameter of nugget, based on an orthogonal test and analysis method. The optimum parameters are as follows： electrode force is 2 000 N, welding heat input is 80% and welding time is 6 cycles. The microstrueture of spot weld is single fine equiaxed crystals in the nugget, of which the structure is β-Mg17Al12 precipitated on α-Mg boundaries induced by nonequilibrium freezing. And the surface condition of the workpiece has great influence on the joint quality.

RIEMANN BOUNDARY VALUE PROBLEMS WITH GIVEN PRINCIPAL PART

In this article, the authors discuss the Riemann boundary value problems with given principal part. First, authors consider a special case and give a classification of the solution class Rn by the way. And then, they consider the general case. The solvable conditions for this problem and its solutions is obtained when it is solvable.

Does the system of independent directors help improve the quality of accounting information： From the perspective of earnings conservatism

Based on the sample data of the listed firms on the A stock market, we analyze how the system of independent directors influence the earning conservatism from 4 dimensions designed to measure the monitoring power of these independent directors： Percentage within BDs, professional capacities, stimulation and work conditions. From the empirical results, we conclude that the more powerful of the independent directors, the better the accounting conservatism, and that their positive impact increases along with the improvement on corporate governance, meanwhile the work conditions plays the most important role, and then are the percentage within BDs and their professional capacities, the stimulation and personal reputation appear the least importance.

Analysis of Serum Metabolic Profile by Ultra-performance Liquid Chromatography-mass Spectrometry for Biomarkers Discovery： Application in a Pilot Study to Discriminate Patients with Tuberculosis

Background：Tuberculosis （TB） is a chronic wasting inflammatory disease characterized by multisystem involvement,which can cause metabolic derangements in afflicted patients.Metabolic signatures have been exploited in the study of several diseases.However,the serum that is successfully used in TB diagnosis on the basis of metabolic profiling is not by much.Methods：Orthogonal partial least-squares discriminant analysis was capable of distinguishing TB patients from both healthy subjects and patients with conditions other than TB.Therefore,TB-specific metabolic profiling was established.Clusters of potential biomarkers for differentiating TB active from non-TB diseases were identified using Mann-Whitney U-test.Multiple logistic regression analysis of metabolites was calculated to determine the suitable biomarker group that allows the efficient differentiation of patients with TB active from the control subjects.Results：From among 271 participants,12 metabolites were found to contribute to the distinction between the TB active group and the control groups.These metabolites were mainly involved in the metabolic pathways of the following three biomolecules：Fatty acids,amino acids,and lipids.The receiver operating characteristic curves of3D,7D,and 11D-phytanic acid,behenic acid,and threoninyl-γ-glutamate exhibited excellent efficiency with area under the curve （AUC） values of 0.904 （95% confidence interval [CI]：0.863-0.944）,0.93 （95% CI：0.893-0.966）,and 0.964 （95% CI：0.941-0.988）,respectively.The largest and smallest resulting AUCs were 0.964 and 0.720,indicating that these biomarkers may be involved in the disease mechanisms.The combination of lysophosphatidylcholine （18∶0）,behenic acid,threoninyl-γ-glutamate,and presqualene diphosphate was used to represent the most suitable biomarker group for the differentiation of patients with TB active from the control subjects,with an AUC value of 0.991.Conclusion：The metabolic analysis results identified new serum biomarkers that can distinguish TB from non-TB diseases.The metabolomics-based analysis provides specific insights into the biology of TB and may offer new avenues for TB diagnosis.

Liutex core line and POD analysis on hairpin vortex formation in natural flow transition

In this study,the new method of the vortex core line based on Liutex definition,also known as Liutex core line,is applied to support the hypothesis that the vortex ring is not a part of theΛ-vortex and the formation of the ring-like vortex is formed separately from theΛ-vortex.The proper orthogonal decomposition(POD)is also applied to analyze the Kelvin-VHelmholtz(K-H)instability happening in hairpin ring areas of the flow transition on the flat plate to understand the mechanism of the ring-like vortex formation.The new vortex identification method named modified Liutex-Omega method is efficiently used to visualize and observe the shapes of vortex structures in 3-D.The streamwise vortex structure characteristics can be found in POD mode one as the mean flow.The other POD modes are in stremwise and spanwise structures and have the fluctuation motions,which are induced by K-H instability.Moreover,the result shows that POD modes are in pairs and share the same characteristics such as amplitudes,mode shapes,and time evolutions.The vortex core and POD results confirm that theΛ-vortex is not self-deformed to a hairpin vortex,but the hairpin vortex is formed by the K-H instability during the development of Lambda vortex to hairpin vortex in the boundary layer flow transition.

Analysis of Phytochemical Constituents of Zuogui Wan in Rat Serum and its Effects on Early Embryonic Development of Mice

Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese medicine.The objective of this study is to elucidate the phytochemical constituents of ZGW-treated rat serum(ZGWRS)using ultra-performance liquid chromatography-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry(UPLC-ESI-Q-TOF-MS).Methods:ZGW was administered to rats,and the phytochemical constituents in rat serum were determined using UPLC-ESI-Q-TOF-MS.MetaboLynx analysis in negative ion mode was adopted to characterize the chemical constituents of ZGWRS.Orthogonal partial least squares discriminant analysis was applied for the discovery of constituents of ZGW that entered the serum of rats.The fertilized eggs collected from the same experiment were randomly divided into four groups,including the normal,40 mmol/L glucose,40 mmol/L glucose 5%control rat serum,and 40 mmol/L glucose 5%ZGWRS groups.They were cultivated at 37°C and 5%CO2 in a saturated humidity CO2 incubator.The blastocyst rate and two-cell rate were used to evaluate the effects of ZGWRS on embryonic development.Results:Thirteen constituents were identified in the ZGWRS,among which sweroside,loganin,morroniside,loganic acid,and 8-epiloganic acid were from Fructus Corni(Shan Zhu Yu).5-Hydroxymethyl-2-furfural-glucuronide,2-H-5-hydroxymethyl-2-furfural-glucuronide,3-hydroxy-2,6,6-trimethyl-1-cyclohexene-1-carboxylic acid,andβ-D-ribofuranuronic acid methyl ester triacetate were from Radix Rehmanniae Preparata(Shu Di Huang).Coumaric acid was from Fructus Lycii(Gou Qi Zi).Kaempferol-3-beta-O-glucuronide and cuscutamine were from Semen Cuscutae(Tu Si Zi).The embryonic development was significantly inhibited using 40 mmol/L glucose.Compared with the normal group,the blastocyst rate of the glucose group was decreased.The blastocyst rate of the 40 mmol/L glucose 5%ZGWRS group was significantly higher than that of the glucose group,indicating that ZGWRS negates the effect of glucose on mouse embryonic development.Conclusion:The results verified that a rapid and robust UPLC-ESI-Q-TOF-MS-based platform had been successful for identifying multiple constituents of ZGW.ZGWRS is rich in active constituents of iridoid glycosides.The results of this study also showed that ZGWRS could negate the effect of glucose on mouse embryonic development.