Striping is a common phenomenon in remote sensing imagery acquired by most spaceborneand airborne multispectral sensors. In contrast to the destriping of the images of optoelectronic mechanical scanners, fewer work ha...Striping is a common phenomenon in remote sensing imagery acquired by most spaceborneand airborne multispectral sensors. In contrast to the destriping of the images of optoelectronic mechanical scanners, fewer work has been done for push-broom CCD images. Based on the characteristics of HY -1 push-broom multispectral CCD camera and its prelaunch radiometric calibration results, the striping features are analyzed and a quantitative striping removal algorithm is proposed. The algorithm is to obtain the inter-detector equalization curves to reflect the differences between detectors by statistic analysis of the satellite imagery data set, and image stripes arising from the nonuniformity of the detectors of the CCD array can be removed using the estimated equalization curves. The preliminary results show that this method can effectively remove the stripes and preserve the radiometric accuracy of the raw data at the same time.展开更多
The Microwave Temperature Sounder(MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technolo...The Microwave Temperature Sounder(MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technology Microwave Sounder(ATMS), striping pattern noise, primarily in the cross-track direction, exists in MWTS-2 radiance observations. In this study, an algorithm based on principal component analysis(PCA) combined with ensemble empirical mode decomposition(EEMD) is described and applied to MWTS-2 brightness temperature observations. It is arguably necessary to smooth the first three principal component(PC) coefficients by removing the first four intrinsic mode functions(IMFs) using the EEMD method(denoted as PC3/IMF4). After the PC3/IMF4 noise mitigation, the striping pattern noise is effectively removed from the brightness temperature observations. The noise level in MWTS-2 observations is significantly higher than that detected in ATMS observations. In May 2014, the scanning profile of MWTS-2 was adjusted from varying-speed scanning to constantspeed scanning. The impact on striping noise levels brought on by this scan profile change is also analyzed here. The striping noise in brightness temperature observations worsened after the profile change. Regardless of the scan profile change, the striping noise mitigation method reported in this study can more or less suppress the noise levels in MWTS-2 observations.展开更多
In order to remove the stripe noises in cotton foreign fiber images by line scanning camera collected, in multi threshold segmentation of rough set, every region’s color is instead of the statistics color of the regi...In order to remove the stripe noises in cotton foreign fiber images by line scanning camera collected, in multi threshold segmentation of rough set, every region’s color is instead of the statistics color of the region. This method can retain the detail information of original image as far as possible, and do well in the stripe noise removal. The roughness of rough set was calculated respectively using directional diagram, Canny operator and Sobel operator. Comparing the three methods, the results indicate that the Canny operator keeps the more details of image, and directional diagram and Sobel operator have the better effects on denoising.展开更多
The current study investigated the effects of intermittent feeding(IF)and fasting strategies at different times post–hatch on muscle growth and white striping(WS)breast development.In the first trial,32 one-day-old A...The current study investigated the effects of intermittent feeding(IF)and fasting strategies at different times post–hatch on muscle growth and white striping(WS)breast development.In the first trial,32 one-day-old Abor Acre broilers were fed ad libitum(AL)for 3 d post–hatch and then randomly allotted into 4 feeding strategies including AL,1h-IF group(1 h IF,4 times feeding/d,1 h each time),1.5h-IF(1.5 h IF,4 times feeding/d,1.5 h each time),and fasting(1d acute fasting,6 d free access to feed)groups and fed for 7 d.Although angiogenic genes including VEGFA,VEGFR1,and VEGFR2,and myogenic genes including MYOG and MYOD were upregulated(P<0.05),the breast muscle satellite cell(SC)number and PAX7,MYF5 expression were decreased by the IF strategies(P<0.05).One-day fasting at 6 d of age also upregulated angiogenic genes and MYOD expression(P<0.05),downregulated MYF5 expression(P<0.05),but did not change SC number(P>0.05).In the second trial,384 one-day-old birds were fed AL for 1 wk and then randomly allotted to the above 4 feeding strategies starting at 8 d of age until 42 d of age.Similarly,IF and fasting strategies upregulated the expression of angiogenic and myogenic genes(P<0.05).Both 1h-IF and 1.5h-IF increased breast muscle SC number(P<0.05).At slaughter,breast muscle fiber diameter of 1.5h-IF was smaller but the SC number was larger than that of the birds fed AL(P<0.05).The IF and fasting strategies prevented WS development,and reduced breast WS scores and triglyceride content(P<0.05)without changing the body weight(P>0.05).Fasting and 1h-IF reduced the expression of adipogenic genes ZNF423 and PDGFRα(P<0.05).Moreover,IF and fasting strategies reduced fibrosis in breast muscle and reduced skeletal muscle-specific E3 ubiquitin ligases(TRIM63 and MAFBX)(P<0.05).Fasting significantly reduced CASPASE-3 in breast muscle(P<0.05).In conclusion,IF starting in the first week decreases SC number.Compared to AL,IF or fasting promotes muscular angiogenesis,increases SC number,prevents muscle degeneration,and prevents the development of WS without impairing the growth performance of broiler chickens.展开更多
Airborne LiDAR data are usually collected with partially overlapping strips in order to serve a seamless and fine resolution mapping purpose.One of the factors limiting the use of intensity data is the presence of str...Airborne LiDAR data are usually collected with partially overlapping strips in order to serve a seamless and fine resolution mapping purpose.One of the factors limiting the use of intensity data is the presence of striping noise found in the overlapping region.Though recent researches have proposed physical and empirical approaches for intensity data correction,the effect of striping noise has not yet been resolved.This paper presents a radiometric normalization technique to normalize the intensity data from one data strip to another one with partial overlap.The normalization technique is built based on a second-order polynomial function fitted on the joint histogram plot,which is generated with a set of pairwise closest data points identified within the overlapping region.The proposed method was tested with two individual LiDAR datasets collected by Teledyne Optech’s Gemini(1064 nm)and Orion(1550 nm)sensors.The experimental results showed that radiometric correction and normalization can significantly reduce the striping noise found in the overlapping LiDAR intensity data and improve its capability in land cover classification.The coefficient of variation of five selected land cover features was reduced by 19–65%,where a 9–18%accuracy improvement was achieved in different classification scenarios.With the proven capability of the proposed method,both radiometric correction and normalization should be applied as a pre-processing step before performing any surface classification and object recognition.展开更多
Theory and practice have confirmed that the propagation of converted transverse waves in azimuthally anisotropic media results in shear-wave splitting,causing differences in travel time and reflection amplitude betwee...Theory and practice have confirmed that the propagation of converted transverse waves in azimuthally anisotropic media results in shear-wave splitting,causing differences in travel time and reflection amplitude between S1/S2 waves,which reduces the imaging quality and vertical resolution of converted transverse wave.Therefore,eliminating shear-wave splitting is one of the important steps in the imaging processing of converted transverse wave.Due to the limitations of actual data acquisition and signal-tonoise ratio,it is difficult to directly determine a set of orthogonal four components for shear-wave splitting analysis,which cannot achieve good correction processing results.To this end,starting from Alford rotation,an orthogonal four component equation system is derived,and the least squares method is used to stably solve the high signal-to-noise ratio orthogonal four components.Based on this,the crack orientation and fast/slow wave delay are estimated through azimuth and time-delay scanning,and the shear-wave splitting correction and fast/slow wave separation are completed by layer striping from shallow to deep.The synthetic data and actual data calculations show that this method can achieve good azimuthal anisotropy correction,separation of S1/S2 waves,and accurate imaging.展开更多
The Earth's crust,the outer shell of the Earth,consists of continental crust and oceanic crust.Oceanic crust is created at the mid-oceanic ridge,where it is magnetized in the ambient field of the Earth.As new mate...The Earth's crust,the outer shell of the Earth,consists of continental crust and oceanic crust.Oceanic crust is created at the mid-oceanic ridge,where it is magnetized in the ambient field of the Earth.As new material is extruded,the crust spreads outward,retaining its magnetization.The reversal of the polarity of the Earth's magnetic field over geologic time leads to a pattern of striped magnetic anomalies.In this study,we carry out a preliminary evaluation on how data from the Macao Science Satellite-1(MSS-1),which has a low orbital inclination,influences inversion models of the oceanic crustal magnetic field when combined with data from the Swarm mission.For our modeling we use an equivalent source method based on a cubed-sphere grid.Our model captures the broad magnetic structure over the North Atlantic Ocean and demonstrates that the trend of magnetic stripes is consistent with the age frame of the oceanic crust.The amplitude of the radial magnetic field at 450 km the North Atlantic Ocean ranges from–11 nT to+8 nT.The addition of MSS-1 observations to Swarm data generates results consistent with the overall magnetic stripe pattern.The lack of short-wavelength scale structure reveals the limitation of high-altitude satellites in portraying fine features and hence lower-altitude observations would be required to delineate a more detailed crustal signature.It is expected to obtain a finer structure of oceanic magnetic stripes by combining low-altitude CHAMP field data and east-west gradient data derived from MSS-1 in future work.展开更多
To realize effective co-phasing adjustment in large-aperture sparse-aperture telescopes,a multichannel stripe tracking approach is employed,allowing simultaneous interferometric measurements of multiple optical paths ...To realize effective co-phasing adjustment in large-aperture sparse-aperture telescopes,a multichannel stripe tracking approach is employed,allowing simultaneous interferometric measurements of multiple optical paths and circumventing the need for pairwise measurements along the mirror boundaries in traditional interferometric methods.This approach enhances detection efficiency and reduces system complexity.Here,the principles of the multibeam interference process and construction of a co-phasing detection module based on direct optical fiber connections were analyzed using wavefront optics theory.Error analysis was conducted on the system surface obtained through multipath interference.Potential applications of the interferometric method were explored.Finally,the principle was verified by experiment,an interferometric fringe contrast better than 0.4 is achieved through flat field calibration and incoherent digital synthesis.The dynamic range of the measurement exceeds 10 times of the center wavelength of the working band(1550 nm).Moreover,a resolution better than one-tenth of the working center wavelength(1550 nm)was achieved.Simultaneous three-beam interference can be achieved,leading to a 50%improvement in detection efficiency.This method can effectively enhance the efficiency of sparse aperture telescope co-phasing,meeting the requirements for observations of 8-10 m telescopes.This study provides a technological foundation for observing distant and faint celestial objects.展开更多
FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in F...FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).展开更多
The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe pa...The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.展开更多
The diversity of rodents in Asian deserts is high.Nevertheless,little is known about their use of daily torpor and hibernation,which are employed by many small mammals worldwide for energy and water conservation to pe...The diversity of rodents in Asian deserts is high.Nevertheless,little is known about their use of daily torpor and hibernation,which are employed by many small mammals worldwide for energy and water conservation to permit survival under adverse environmental conditions.We quantified for the first time,using temperature transponders and data loggers,long-term torpor expression and patterns in sympatric desert hamsters Phodopus roborovskii,striped hamsters Cricetulus barabensis and 3-toed jerboas Dipus sagitta under controlled conditions.Animals were live-trapped in Inner Mongolia in August and held in captivity under short photoperiods and low ambient temperatures(T,s)for about 6 months.Both hamster species(~half of individuals)expressed spontaneous(food available)daily torpor.Daily torpor in desert hamsters was less frequent and shallower than that in striped hamsters,which also had longer torpor bouts during torpor at T 15.8±0.4℃.Only one individual jerboa entered hibernation spontaneously at T,6.2±0.5℃,but all hibernated after food deprivation.The 2 hamster species only slightly changed their body mass during the acclimation,whereas jerboas greatly increased their body mass by 27.9%during the first 2 months of acclimation probably as a preparation for the hibernating season.Our data show that short photoperiod and moderately low T,induces spontaneous daily torpor in the 2 hamster species,suggesting that it is used regularly in the wild.Hibernation in Jerboas occurred at T,6.2±0.5°C especially when food was withheld suggesting limited food availability is the proximate trigger of their hibernation.展开更多
Aegilops variabilis(S^(v)S^(v)U^(v)U^(v))is a source of resistance to wheat stripe rust.The phKL locus in Chinese common wheat landrace Kaixian-Luohanmai(KL)can induce homoeologous wheat-alien chromosome pairing and r...Aegilops variabilis(S^(v)S^(v)U^(v)U^(v))is a source of resistance to wheat stripe rust.The phKL locus in Chinese common wheat landrace Kaixian-Luohanmai(KL)can induce homoeologous wheat-alien chromosome pairing and recombination.In this study,we confirmed that the whole 2S^(v)chromosome introgressed into wheat from Ae.variabilis accession AS116 conferred all-stage stripe rust resistance.The underlying gene(s),named YrAev,was mapped to the long arm 2S^(v)L using an F_(2)population.Two 2S^(v)-2B recombinants,derived from a cross of the 2S^(v)(2B)chromosome substitution line and KL,were confirmed to harbor the resistance locus.The physical region containing YrAev,determined from RNA-seq data,was 844.6-852.1 Mb on the chromosome arm 2S^(l)of the Ae.longissima(S^(v)genome donor species of Ae.variabilis)accession TL05 assembly v1.0.Differential gene expression analysis of post-inoculation with the Pst race has indicated two disease-resistance-related genes(annotated as mixed lineage kinase domain-like protein and nucleotide-binding leucine-rich repeat like protein,respectively)as promising candidates for YrAev.This study demonstrates the utility of the phKL gene system in alien gene localization and transfer.The resistant translocation line harboring YrAev can be exploited by wheat breeders as a novel source of resistance to stripe rust.展开更多
Amplitude stripes imposed by ionospheric scintillation have been frequently observed in many of the equatorial nighttime acquisitions of the Advanced Land Observing Satellite(ALOS)Phased Array-type L-band Synthetic Ap...Amplitude stripes imposed by ionospheric scintillation have been frequently observed in many of the equatorial nighttime acquisitions of the Advanced Land Observing Satellite(ALOS)Phased Array-type L-band Synthetic Aperture Radar(PALSAR).This type of ionospheric artifact impedes PALSAR interferometric and polarimetric applications,and its formation cause,morphology,and negative influence have been deeply investigated.However,this artifact can provide an alternative opportunity in a positive way for probing and measuring ionosphere scintillation.In this paper,a methodology for measuring ionospheric scintillation parameters from PALSAR images with amplitude stripes is proposed.Firstly,sublook processing is beneficial for recovering the scattered stripes from a single-look complex image;the amplitude stripe pattern is extracted via band-rejection filtering in the frequency domain of the sublook image.Secondly,the amplitude spectrum density function(SDF)is estimated from the amplitude stripe pattern.Thirdly,a fitting scheme for measuring the scintillation strength and spectrum index is conducted between the estimated and theoretical long-wavelength SDFs.In addition,another key parameter,the scintillation index,can be directly measured from the amplitude stripe pattern or indirectly derived from the scintillation strength and spectrum index.The proposed methodology is fully demonstrated on two groups of PALSAR acquisitions in the presence of amplitude stripes.Self-validation is conducted by comparing the measured and derived scintillation index and by comparing the measurements of range lines and azimuth lines.Cross-validation is performed by comparing the PALSAR measurements with in situ Global Position System(GPS)measurements.The processing results demonstrate a powerful capability to robustly measure ionospheric scintillation parameters from space with high spatial resolution.展开更多
Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), is an airborne disease. In China, it frequently develops initially in central Shaanxi and southwestern Gansu, and from there, inoculum spreads to ...Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), is an airborne disease. In China, it frequently develops initially in central Shaanxi and southwestern Gansu, and from there, inoculum spreads to the eastern wheat production regions. Field investigations have suggested that Pst could spread from the west to the east within central Shaanxi andthat Gansu could serve as the inoculum source for central Shaanxi, but there is no direct evidence for this hypothetical dispersal route. In the current study, 321 Pst isolates collected from central Shaanxi and Gansu in the 2019–2020 and2020–2021 winter wheat cropping seasons were genotyped using 23 pairs of KASP-SNP markers. The dispersion among subpopulations was analyzed using several approaches, and overall, the populations were found to exhibit high levels of genetic diversity. There was little genetic divergence(0.05>FST>0) within central Shaanxi. However, significant gene flow(Nm>4) driven by wind-oriented dispersal from west(Baoji) to east(Weinan) occurred. There was also gene flow among the 4 Gansu subpopulations of Tianshui, Longnan, Pingliang, and Qingyang. Migration of the pathogen occurred between central Shaanxi and Gansu. Migration from Gansu to central Shaanxi was major compared with that from central Shaanxi to Gansu that was minor. Genetic variation occurred among isolates, instead of among subpopulations and within isolates. Linkage disequilibrium revealed that there was strong genetic recombination in the subpopulations from Gansu and central Shaanxi. Therefore, the present study provides molecular evidence that Pst spread from west to east in central Shaanxi and showed that Gansu(especially Longnan and Tianshui) was one of the major origins of the pathogen inoculum of wheat stripe rust in central Shaanxi. The results revealed the west-to-east transmission route of wheat stripe rust in central Shaanxi, being used to guide integrated management of the disease.展开更多
1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was fir...1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was first recognized in the early 1900s,when Biffen(1905)demonstrated that resistance to stripe rust in wheat(Triticum aestivum)followed Mendelian rules of inheritance[2].This foundational insight was later expanded by Flor(1942),who formulated the“gene-for-gene”model describing the genetic interplay between host resistance(R)genes and pathogen avirulence(Avr)genes[3].展开更多
[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experiment...[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.展开更多
[Objective] The study aimed to screen wheat cultivars with high temperature resistance to stripe rust from the wheat resources in Huanghuai growth area. [Method] Seedlings of 165 wheat cultivars from Huanghuai growth ...[Objective] The study aimed to screen wheat cultivars with high temperature resistance to stripe rust from the wheat resources in Huanghuai growth area. [Method] Seedlings of 165 wheat cultivars from Huanghuai growth area were identified by wheat stripe rust under high temperature; then the wheat cultivars showing stripe rust at seedling stage were further used to identify the same resistance in field. [Results] 13 cultivars were proved to be stripe rust resistant under high temperature, and the expression stages of stripe rust in the 13 cultivars were revealed. The field identification results confirmed the identification results at seedling stage via inoculation of mixed stripe rust of physiological races. The stripe resistances of wheat cultivars were also proved to be non-race-specific. [Conclusion] Wheat resources in Huanghuai growth area are abundant in wheat cultivars with high temperature resistance to stripe rust.展开更多
Wheat stripe rust has become the most dangerous disease which threaten safe yield of wheat in Sichuan Province. It is meaningful to provide technique support for integrated disease control by exploring the effective c...Wheat stripe rust has become the most dangerous disease which threaten safe yield of wheat in Sichuan Province. It is meaningful to provide technique support for integrated disease control by exploring the effective control measures of wheat stripe rust. Wheat stripe rust dynamic developments of all-planting and mixed-planting have been systematically investigated in this study by taking different mixed-planting combinations among 6 wheat varieties with different resistance levels. The results of this experiment show that the mixed-plantings of 4 and 6 wheat varieties can delay the occurance of wheat stripe rust,slow the speed of disease and decline the damage of disease as well as stabilize yield of wheats.展开更多
基金This work was supported by the HY- 1 satellite project of the National Satellite Ocean Application Service.
文摘Striping is a common phenomenon in remote sensing imagery acquired by most spaceborneand airborne multispectral sensors. In contrast to the destriping of the images of optoelectronic mechanical scanners, fewer work has been done for push-broom CCD images. Based on the characteristics of HY -1 push-broom multispectral CCD camera and its prelaunch radiometric calibration results, the striping features are analyzed and a quantitative striping removal algorithm is proposed. The algorithm is to obtain the inter-detector equalization curves to reflect the differences between detectors by statistic analysis of the satellite imagery data set, and image stripes arising from the nonuniformity of the detectors of the CCD array can be removed using the estimated equalization curves. The preliminary results show that this method can effectively remove the stripes and preserve the radiometric accuracy of the raw data at the same time.
基金supported by the National Key R&D Program (Grant No. 2018YFC1506702)
文摘The Microwave Temperature Sounder(MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technology Microwave Sounder(ATMS), striping pattern noise, primarily in the cross-track direction, exists in MWTS-2 radiance observations. In this study, an algorithm based on principal component analysis(PCA) combined with ensemble empirical mode decomposition(EEMD) is described and applied to MWTS-2 brightness temperature observations. It is arguably necessary to smooth the first three principal component(PC) coefficients by removing the first four intrinsic mode functions(IMFs) using the EEMD method(denoted as PC3/IMF4). After the PC3/IMF4 noise mitigation, the striping pattern noise is effectively removed from the brightness temperature observations. The noise level in MWTS-2 observations is significantly higher than that detected in ATMS observations. In May 2014, the scanning profile of MWTS-2 was adjusted from varying-speed scanning to constantspeed scanning. The impact on striping noise levels brought on by this scan profile change is also analyzed here. The striping noise in brightness temperature observations worsened after the profile change. Regardless of the scan profile change, the striping noise mitigation method reported in this study can more or less suppress the noise levels in MWTS-2 observations.
文摘In order to remove the stripe noises in cotton foreign fiber images by line scanning camera collected, in multi threshold segmentation of rough set, every region’s color is instead of the statistics color of the region. This method can retain the detail information of original image as far as possible, and do well in the stripe noise removal. The roughness of rough set was calculated respectively using directional diagram, Canny operator and Sobel operator. Comparing the three methods, the results indicate that the Canny operator keeps the more details of image, and directional diagram and Sobel operator have the better effects on denoising.
基金financially supported by the National Key R&D Program of China(2018YFE0127300)the 2115 Talent Development Program of China Agricultural Universitythe Young Talent Supporting Program Funding of the College of Animal Science and Technology,China Agricultural University Education Foundation Grant (1041-2221002).
文摘The current study investigated the effects of intermittent feeding(IF)and fasting strategies at different times post–hatch on muscle growth and white striping(WS)breast development.In the first trial,32 one-day-old Abor Acre broilers were fed ad libitum(AL)for 3 d post–hatch and then randomly allotted into 4 feeding strategies including AL,1h-IF group(1 h IF,4 times feeding/d,1 h each time),1.5h-IF(1.5 h IF,4 times feeding/d,1.5 h each time),and fasting(1d acute fasting,6 d free access to feed)groups and fed for 7 d.Although angiogenic genes including VEGFA,VEGFR1,and VEGFR2,and myogenic genes including MYOG and MYOD were upregulated(P<0.05),the breast muscle satellite cell(SC)number and PAX7,MYF5 expression were decreased by the IF strategies(P<0.05).One-day fasting at 6 d of age also upregulated angiogenic genes and MYOD expression(P<0.05),downregulated MYF5 expression(P<0.05),but did not change SC number(P>0.05).In the second trial,384 one-day-old birds were fed AL for 1 wk and then randomly allotted to the above 4 feeding strategies starting at 8 d of age until 42 d of age.Similarly,IF and fasting strategies upregulated the expression of angiogenic and myogenic genes(P<0.05).Both 1h-IF and 1.5h-IF increased breast muscle SC number(P<0.05).At slaughter,breast muscle fiber diameter of 1.5h-IF was smaller but the SC number was larger than that of the birds fed AL(P<0.05).The IF and fasting strategies prevented WS development,and reduced breast WS scores and triglyceride content(P<0.05)without changing the body weight(P>0.05).Fasting and 1h-IF reduced the expression of adipogenic genes ZNF423 and PDGFRα(P<0.05).Moreover,IF and fasting strategies reduced fibrosis in breast muscle and reduced skeletal muscle-specific E3 ubiquitin ligases(TRIM63 and MAFBX)(P<0.05).Fasting significantly reduced CASPASE-3 in breast muscle(P<0.05).In conclusion,IF starting in the first week decreases SC number.Compared to AL,IF or fasting promotes muscular angiogenesis,increases SC number,prevents muscle degeneration,and prevents the development of WS without impairing the growth performance of broiler chickens.
基金The research was supported by the Natural Sciences and Engineering Research Council of Canada[RGPIN-2015-03960].
文摘Airborne LiDAR data are usually collected with partially overlapping strips in order to serve a seamless and fine resolution mapping purpose.One of the factors limiting the use of intensity data is the presence of striping noise found in the overlapping region.Though recent researches have proposed physical and empirical approaches for intensity data correction,the effect of striping noise has not yet been resolved.This paper presents a radiometric normalization technique to normalize the intensity data from one data strip to another one with partial overlap.The normalization technique is built based on a second-order polynomial function fitted on the joint histogram plot,which is generated with a set of pairwise closest data points identified within the overlapping region.The proposed method was tested with two individual LiDAR datasets collected by Teledyne Optech’s Gemini(1064 nm)and Orion(1550 nm)sensors.The experimental results showed that radiometric correction and normalization can significantly reduce the striping noise found in the overlapping LiDAR intensity data and improve its capability in land cover classification.The coefficient of variation of five selected land cover features was reduced by 19–65%,where a 9–18%accuracy improvement was achieved in different classification scenarios.With the proven capability of the proposed method,both radiometric correction and normalization should be applied as a pre-processing step before performing any surface classification and object recognition.
基金supported by Sinopec Science and Technology Research Project(P23098,P25152).
文摘Theory and practice have confirmed that the propagation of converted transverse waves in azimuthally anisotropic media results in shear-wave splitting,causing differences in travel time and reflection amplitude between S1/S2 waves,which reduces the imaging quality and vertical resolution of converted transverse wave.Therefore,eliminating shear-wave splitting is one of the important steps in the imaging processing of converted transverse wave.Due to the limitations of actual data acquisition and signal-tonoise ratio,it is difficult to directly determine a set of orthogonal four components for shear-wave splitting analysis,which cannot achieve good correction processing results.To this end,starting from Alford rotation,an orthogonal four component equation system is derived,and the least squares method is used to stably solve the high signal-to-noise ratio orthogonal four components.Based on this,the crack orientation and fast/slow wave delay are estimated through azimuth and time-delay scanning,and the shear-wave splitting correction and fast/slow wave separation are completed by layer striping from shallow to deep.The synthetic data and actual data calculations show that this method can achieve good azimuthal anisotropy correction,separation of S1/S2 waves,and accurate imaging.
基金supported by the National Natural Science Foundation of China(42250101,42250102,42250103)the Macao Foundation,and the Science and Technology Development Fund,Macao SAR(File No.0002/2019/APD)。
文摘The Earth's crust,the outer shell of the Earth,consists of continental crust and oceanic crust.Oceanic crust is created at the mid-oceanic ridge,where it is magnetized in the ambient field of the Earth.As new material is extruded,the crust spreads outward,retaining its magnetization.The reversal of the polarity of the Earth's magnetic field over geologic time leads to a pattern of striped magnetic anomalies.In this study,we carry out a preliminary evaluation on how data from the Macao Science Satellite-1(MSS-1),which has a low orbital inclination,influences inversion models of the oceanic crustal magnetic field when combined with data from the Swarm mission.For our modeling we use an equivalent source method based on a cubed-sphere grid.Our model captures the broad magnetic structure over the North Atlantic Ocean and demonstrates that the trend of magnetic stripes is consistent with the age frame of the oceanic crust.The amplitude of the radial magnetic field at 450 km the North Atlantic Ocean ranges from–11 nT to+8 nT.The addition of MSS-1 observations to Swarm data generates results consistent with the overall magnetic stripe pattern.The lack of short-wavelength scale structure reveals the limitation of high-altitude satellites in portraying fine features and hence lower-altitude observations would be required to delineate a more detailed crustal signature.It is expected to obtain a finer structure of oceanic magnetic stripes by combining low-altitude CHAMP field data and east-west gradient data derived from MSS-1 in future work.
文摘To realize effective co-phasing adjustment in large-aperture sparse-aperture telescopes,a multichannel stripe tracking approach is employed,allowing simultaneous interferometric measurements of multiple optical paths and circumventing the need for pairwise measurements along the mirror boundaries in traditional interferometric methods.This approach enhances detection efficiency and reduces system complexity.Here,the principles of the multibeam interference process and construction of a co-phasing detection module based on direct optical fiber connections were analyzed using wavefront optics theory.Error analysis was conducted on the system surface obtained through multipath interference.Potential applications of the interferometric method were explored.Finally,the principle was verified by experiment,an interferometric fringe contrast better than 0.4 is achieved through flat field calibration and incoherent digital synthesis.The dynamic range of the measurement exceeds 10 times of the center wavelength of the working band(1550 nm).Moreover,a resolution better than one-tenth of the working center wavelength(1550 nm)was achieved.Simultaneous three-beam interference can be achieved,leading to a 50%improvement in detection efficiency.This method can effectively enhance the efficiency of sparse aperture telescope co-phasing,meeting the requirements for observations of 8-10 m telescopes.This study provides a technological foundation for observing distant and faint celestial objects.
基金supported by the National Natural Science Foundation of China(Grant Nos.11204131 and 11974181)。
文摘FeSe is an Fe-based paramagnetic superconductor with the simplest structure.The competition between the Néel and stripe magnetic orders is believed to be one of the reasons for the absence of magnetic orders in FeSe.FeSe is recognized as a prototypical platform for competing magnetic interactions,including Néel,stripe,and staggered antiferromagnetic coupling.However,the correlations between these magnetic orders and how they change with varying environmental conditions require further study.Here,we calculated the magnetic order of monolayer FeSe in three diferent environments:pure one,with slight lattice distortion,and on SrTiO_(3) substrate,by frst principles calculations.We fnd that in the calculated dispersion relation E(q)between the spin spiral energy E and spin spiral vector q of the monolayer FeSe structure,the stripe magnetic order M(π/2,π/2)has the lowest energy,and there is a fat E(q)between the wave vector X(π/2,0)and Néel magnetic order 2X(π,0),which are the degenerate E(q)states.The ground state of M and the highest density of states around 2X may be the reason for the competition of two magnetic orders.The slight lattice distortion does not alter the magnetic properties of monolayer FeSe.When monolayer FeSe is attached to the SrTiO_(3)substrate,the degenerate E(q)is still retained;meanwhile,the energy of the 2X(π,0)state is closer to the M state,which may be one of the reasons for the increase of superconducting temperature in FeSe/SrTiO_(3).
基金supported by grants from theKey Scientific and Technological Project of Henan Province,China(222102110124)the Joint Fund of Science and Technology Research and Development Plan,Henan Province,China(222103810009)+4 种基金the National Natural Science Foundation of China(32172574,3217180560)the Funding of Joint Research on Agricultural Varieties Improvement of Henan Province,China(2022010503)the Major Science and Technology Project of Henan Province,China(221100110400)the Natural Science Foundation of Henan,China(222300420050)the Science and Technology Innovation Talent Support Program of Henan Province,China(23HASTIT034).
文摘The color and pattern of watermelon rind are crucial external traits that directly affect consumer preferences.Watermelons with stripes having a stronger color than the background rind are ideal for studying stripe patterns in plants,while there is still limited knowledge about the genetic mechanisms underlying stripe coloration due to the lack of germplasm resources.In this study,we focused on a watermelon germplasm with colorless stripes,and genetic analysis revealed that the trait is controlled by a single recessive gene.The gene Clsc(Citrullus lanatus stripe coloration),which is responsible for the colorless stripe,was localized into a 147.6 kb region on Chr9 by linkage analysis in a large F2 mapping population.Further analysis revealed that the Cla97C09G175170 gene encodes the APRR2 transcription factor,plays a crucial role in determining the watermelon colorless stripe phenotype and was deduced to be related to chlorophyll synthesis and chloroplast development.Physiological experiments indicated that Cla97C09G175170 may significantly influence chloroplast development and chlorophyll synthesis in watermelon.The results of this study provide a better understanding of the molecular mechanism of stripe coloration in watermelon and can be useful in the development of marker-assisted selection(MAS)for new watermelon cultivars.
基金supported by grants from the National Natural Science Foundation of China to QSC(31470473 and 32260261)a Chinese Academy of Sciences Visiting Scientists Fellowship to FG.
文摘The diversity of rodents in Asian deserts is high.Nevertheless,little is known about their use of daily torpor and hibernation,which are employed by many small mammals worldwide for energy and water conservation to permit survival under adverse environmental conditions.We quantified for the first time,using temperature transponders and data loggers,long-term torpor expression and patterns in sympatric desert hamsters Phodopus roborovskii,striped hamsters Cricetulus barabensis and 3-toed jerboas Dipus sagitta under controlled conditions.Animals were live-trapped in Inner Mongolia in August and held in captivity under short photoperiods and low ambient temperatures(T,s)for about 6 months.Both hamster species(~half of individuals)expressed spontaneous(food available)daily torpor.Daily torpor in desert hamsters was less frequent and shallower than that in striped hamsters,which also had longer torpor bouts during torpor at T 15.8±0.4℃.Only one individual jerboa entered hibernation spontaneously at T,6.2±0.5℃,but all hibernated after food deprivation.The 2 hamster species only slightly changed their body mass during the acclimation,whereas jerboas greatly increased their body mass by 27.9%during the first 2 months of acclimation probably as a preparation for the hibernating season.Our data show that short photoperiod and moderately low T,induces spontaneous daily torpor in the 2 hamster species,suggesting that it is used regularly in the wild.Hibernation in Jerboas occurred at T,6.2±0.5°C especially when food was withheld suggesting limited food availability is the proximate trigger of their hibernation.
基金supported by the National Natural Science Foundation of China(32172020,31971884)the National Key Research and Development Program of China(2024YFD1201202,2024YFD1200402)+4 种基金the Sichuan Science and Technology Program(2022ZDZX0014,2023YFN0085)the Qinghai Provincial Key Laboratory of Crop Molecular Breeding(2023-1-1)the State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China(SKLKF202409)the Alliance of National and International Science Organizations for the Belt and Road Regions(ANSO-CR-KP-202205)the International Partnership Program of Chinese Academy of Sciences(077GJHZ2023028GC)。
文摘Aegilops variabilis(S^(v)S^(v)U^(v)U^(v))is a source of resistance to wheat stripe rust.The phKL locus in Chinese common wheat landrace Kaixian-Luohanmai(KL)can induce homoeologous wheat-alien chromosome pairing and recombination.In this study,we confirmed that the whole 2S^(v)chromosome introgressed into wheat from Ae.variabilis accession AS116 conferred all-stage stripe rust resistance.The underlying gene(s),named YrAev,was mapped to the long arm 2S^(v)L using an F_(2)population.Two 2S^(v)-2B recombinants,derived from a cross of the 2S^(v)(2B)chromosome substitution line and KL,were confirmed to harbor the resistance locus.The physical region containing YrAev,determined from RNA-seq data,was 844.6-852.1 Mb on the chromosome arm 2S^(l)of the Ae.longissima(S^(v)genome donor species of Ae.variabilis)accession TL05 assembly v1.0.Differential gene expression analysis of post-inoculation with the Pst race has indicated two disease-resistance-related genes(annotated as mixed lineage kinase domain-like protein and nucleotide-binding leucine-rich repeat like protein,respectively)as promising candidates for YrAev.This study demonstrates the utility of the phKL gene system in alien gene localization and transfer.The resistant translocation line harboring YrAev can be exploited by wheat breeders as a novel source of resistance to stripe rust.
基金supported partly by the National Natural Science Foundation of China(NSFC)(62101568 and 62371460)the Scientific Research Program of the National University of Defense Technology(ZK21-06)the Taishan Scholars of Shandong Province(ts20190968)。
文摘Amplitude stripes imposed by ionospheric scintillation have been frequently observed in many of the equatorial nighttime acquisitions of the Advanced Land Observing Satellite(ALOS)Phased Array-type L-band Synthetic Aperture Radar(PALSAR).This type of ionospheric artifact impedes PALSAR interferometric and polarimetric applications,and its formation cause,morphology,and negative influence have been deeply investigated.However,this artifact can provide an alternative opportunity in a positive way for probing and measuring ionosphere scintillation.In this paper,a methodology for measuring ionospheric scintillation parameters from PALSAR images with amplitude stripes is proposed.Firstly,sublook processing is beneficial for recovering the scattered stripes from a single-look complex image;the amplitude stripe pattern is extracted via band-rejection filtering in the frequency domain of the sublook image.Secondly,the amplitude spectrum density function(SDF)is estimated from the amplitude stripe pattern.Thirdly,a fitting scheme for measuring the scintillation strength and spectrum index is conducted between the estimated and theoretical long-wavelength SDFs.In addition,another key parameter,the scintillation index,can be directly measured from the amplitude stripe pattern or indirectly derived from the scintillation strength and spectrum index.The proposed methodology is fully demonstrated on two groups of PALSAR acquisitions in the presence of amplitude stripes.Self-validation is conducted by comparing the measured and derived scintillation index and by comparing the measurements of range lines and azimuth lines.Cross-validation is performed by comparing the PALSAR measurements with in situ Global Position System(GPS)measurements.The processing results demonstrate a powerful capability to robustly measure ionospheric scintillation parameters from space with high spatial resolution.
基金supported by the National Key R&D Program of China (2021YFD1401000)the National Natural Science Foundation of China (32072358 and 32272507)the Natural Science Basic Research Plan in Shaanxi Province, China (2020JZ-15)。
文摘Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici(Pst), is an airborne disease. In China, it frequently develops initially in central Shaanxi and southwestern Gansu, and from there, inoculum spreads to the eastern wheat production regions. Field investigations have suggested that Pst could spread from the west to the east within central Shaanxi andthat Gansu could serve as the inoculum source for central Shaanxi, but there is no direct evidence for this hypothetical dispersal route. In the current study, 321 Pst isolates collected from central Shaanxi and Gansu in the 2019–2020 and2020–2021 winter wheat cropping seasons were genotyped using 23 pairs of KASP-SNP markers. The dispersion among subpopulations was analyzed using several approaches, and overall, the populations were found to exhibit high levels of genetic diversity. There was little genetic divergence(0.05>FST>0) within central Shaanxi. However, significant gene flow(Nm>4) driven by wind-oriented dispersal from west(Baoji) to east(Weinan) occurred. There was also gene flow among the 4 Gansu subpopulations of Tianshui, Longnan, Pingliang, and Qingyang. Migration of the pathogen occurred between central Shaanxi and Gansu. Migration from Gansu to central Shaanxi was major compared with that from central Shaanxi to Gansu that was minor. Genetic variation occurred among isolates, instead of among subpopulations and within isolates. Linkage disequilibrium revealed that there was strong genetic recombination in the subpopulations from Gansu and central Shaanxi. Therefore, the present study provides molecular evidence that Pst spread from west to east in central Shaanxi and showed that Gansu(especially Longnan and Tianshui) was one of the major origins of the pathogen inoculum of wheat stripe rust in central Shaanxi. The results revealed the west-to-east transmission route of wheat stripe rust in central Shaanxi, being used to guide integrated management of the disease.
基金supported by the National Natural Science Foundation of China (U21A20224)the Key Research and Development Program of Ministry of Science and Technology of China(2023YFD1200402) to Zhiyong Liuby funding from King Abdullah University of Science and Technology to Brande B.H.Wulff
文摘1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was first recognized in the early 1900s,when Biffen(1905)demonstrated that resistance to stripe rust in wheat(Triticum aestivum)followed Mendelian rules of inheritance[2].This foundational insight was later expanded by Flor(1942),who formulated the“gene-for-gene”model describing the genetic interplay between host resistance(R)genes and pathogen avirulence(Avr)genes[3].
基金Supported by Program for New Century Excellent Talents in University(NCET-04-0907)the Innovative Research Team in University (IRT0453)~~
文摘[Objective] The experiment aimed to explore physiological and biochemical changes of leaves after plants were mutated. [Method] A rice double mutant with stripes on stems, leaves and spikelets were taken as experimental materials to study the enzyme activity changes in different growth stages and amino acid variation in rice. [ Result] The SOD activity in mutant was higher than that in wild plant at tillering metaphase, but lower than that in wild type before heading stage and late flowering; the POD activity in three stages increased firstly then declined and the activity showed highest maximal activity at before heading stage. However, the POD activity in wild type showed the opposite change trend; the CAT activity presented degression at three stages, especially high at tillering metaphase, but reverse changes in wild type; the MDA activity decreased at three stages, but it was still higher than that in wild type, besides, the soluble sugar content of mutant was lower, but total amino acid content was increased. [ Conclusion] The expression of mutant characteristics was correlated with SOD, POD, CAT and MDA activity Changes and these changes made the mutant survive and rice quality change at last.
文摘[Objective] The study aimed to screen wheat cultivars with high temperature resistance to stripe rust from the wheat resources in Huanghuai growth area. [Method] Seedlings of 165 wheat cultivars from Huanghuai growth area were identified by wheat stripe rust under high temperature; then the wheat cultivars showing stripe rust at seedling stage were further used to identify the same resistance in field. [Results] 13 cultivars were proved to be stripe rust resistant under high temperature, and the expression stages of stripe rust in the 13 cultivars were revealed. The field identification results confirmed the identification results at seedling stage via inoculation of mixed stripe rust of physiological races. The stripe resistances of wheat cultivars were also proved to be non-race-specific. [Conclusion] Wheat resources in Huanghuai growth area are abundant in wheat cultivars with high temperature resistance to stripe rust.
文摘Wheat stripe rust has become the most dangerous disease which threaten safe yield of wheat in Sichuan Province. It is meaningful to provide technique support for integrated disease control by exploring the effective control measures of wheat stripe rust. Wheat stripe rust dynamic developments of all-planting and mixed-planting have been systematically investigated in this study by taking different mixed-planting combinations among 6 wheat varieties with different resistance levels. The results of this experiment show that the mixed-plantings of 4 and 6 wheat varieties can delay the occurance of wheat stripe rust,slow the speed of disease and decline the damage of disease as well as stabilize yield of wheats.
