Comparison and Verification of Coherent Doppler Wind Lidar and Radiosonde Data in the Beijing Urban Area

As a new type of wind field detection equipment, coherent Doppler wind lidar(CDWL) still needs more relevant observation experiments to compare and verify whether it can achieve the accuracy and precision of traditional observation equipment in urban areas. In this experiment, a self-developed CDWL provided four months of observations in the southern Beijing area. After the data acquisition time and height match, the wind profile data obtained based on a Doppler beam swinging(DBS) five-beam inversion algorithm were compared with radiosonde data released from the same location. The standard deviation(SD) of wind speed is 0.8 m s^(–1), and the coefficient of determination R~2 is 0.95. The SD of the wind direction is 17.7° with an R~2 of 0.96. Below the height of the roughness sublayer(about 400 m), the error in wind speed and wind direction is significantly greater than the error above the height of the boundary layer(about 1500 m). For the case of wind speeds less than 4 m s^(–1), the error of wind direction is more significant and is affected by the distribution of surrounding buildings. Averaging at different height levels using suitable time windows can effectively reduce the effects of turbulence and thus reduce the error caused by the different measurement methods of the two devices.

Genome-wide association study of vitamin E in sweet corn kernels

Vitamin E,consisting of tocopherols and tocotrienols,serves as a lipid-soluble antioxidant in sweet corn kernels,providing nutrients to both plants and humans.Though the key genes involved in the vitamin E biosynthesis pathway have been identified in plants,the genetic architecture of vitamin E content in sweet corn kernels remains largely unclear.In the present study,an association panel of 204 inbred lines of sweet corn was constructed.Seven compounds of vitamin E were quantified in sweet corn kernels at 28 days after pollination.A total of 119 loci for vitamin E were identified using a genome-wide association study based on genotyping by sequencing,and a genetic network of vitamin E was constructed.Candidate genes identified were involved mainly in RNA regulation and protein metabolism.The known gene ZmVTE4,encodingγ-tocopherol methyltransferase,was significantly associated with four traits(α-tocopherol,α-tocotrienol,theα/γ-tocopherol ratio,and theα/γ-tocotrienol ratio).The effects of two causative markers on ZmVTE4 were validated by haplotype analysis.Finally,two elite cultivars(Yuetian 9 and Yuetian 22)with a 4.5-fold increase in the sum ofα-andγ-tocopherols were developed by marker-assisted selection,demonstrating the successful biofortification of sweet corn.Three genes(DAHPS,ADT2,and cmu2)involved in chorismate and tyrosine synthesis were significantly associated with theα/γ-tocotrienol ratio.These results shed light on the genetic architecture of vitamin E and may accelerate the nutritional improvement of sweet corn.

Comparative transcriptome analysis of sweet corn seedlings under low-temperature stress

Stress induced by low temperature, which represents a widespread environmental factor,strongly affects maize growth and yield. However, the physiological characteristics and molecular regulatory mechanisms of maize seedlings in response to cold remain poorly understood. In this study, using RNA-seq, we investigated the transcriptome profiles of two sweet com inbred lines, "Richao"(RC) and C5, under cold stress. A total of 357 and 455 differentially expressed genes(DEGs) were identified in the RC and C5 lines, respectively, 94 DEGs were detected as common DEGs related to cold response in both genotypes, and a total of 589 DEGs were detected as cold tolerance-associated genes. By combining protein function clustering analysis and significantly enriched Gene Ontology(GO) terms analysis,we suggest that transcription factors may play a dominating role in the cold stress response and tolerance of sweet com. Furthermore, 74 differentially expressed transcription factors were identified, of those many genes involved in the metabolism and regulation of hormones. These results expand our understanding of the complex mechanisms involved in chilling tolerance in maize, and provide a set of candidate genes for further genetic analyses.

Correction: The NAC transcription factor ClNAC68 positively regulates sugar content and seed development in watermelon by repressing ClINV and ClGH3.6

In this article 1,author name Yanping Wang was incorrectly tagged as corresponding author.Prof.Wang should be the co-first author,instead of the corresponding author.The original article has been corrected.

The NAC transcription factor CINAC68 positively regulates sugar content and seed development in watermelon by repressing CIINV and CIGH3.6

NAC(NAM,ATAF1/2,and CUC2)transcription factors play important roles in fruit ripening and quality.The watermelon genome encodes 80 NAC genes,and 21 of these NAC genes are highly expressed in both the flesh and vascular tissues.Among these genes,CINAC68 expression was signi fi cantly higher in flesh than in rind.However,the intrinsic regulatory mechanism of CINAC68 in fruit ripening and quality is still unknown.In this study,we found that ClNAC68 is a transcriptional repressor and that the repression domain is located in the C-terminus.Knockout of CINAC68 by the CRISPR-Cas9 system decreased the soluble solid content and sucrose accumulation in mutant flesh.Development was delayed,germination was inhibited,and the IAA content was signi ficantly decreased in mutant seeds.Transcriptome analysis showed that the invertase gene CUNV was the only gene involved in sucrose metabolism that was upregulated in mutant flesh,and expression of the indole-3-acetic acid-amido synthetase gene CIGH3.6 in the IAA signaling pathway was also induced in mutant seeds.EMSA and dual-luciferase assays showed that CINAC68 directly bound to the promoters of CUNV and CIGH3.6 to repress their expression.These results indicated that CINAC68 positively regulated sugar and IAA accumulation by repressing CUNV and CIGH3.6.Our findings provide new insights into the regulatory mechanisms by which NAC transcription factors affect fruit quality and seed development.

Ureteral reconstruction with decellularized small intestinal submucosa matrix for ureteral stricture: A preliminary report of two cases

Objective:To determine the feasibility of decellularized small intestinal submu-cosa(5IS)matrix in repairing ureteral strictures.Methods:Two patients with ureteral stenoses underwent ureteral reconstruction with SIS ma-trix at the Zhejiang Provincial Corps Hospital of Chinese People's Armed Forces between June 2014 and June 2016.The ureteral stenoses were repaired with a semi-tubular SIS matrix and the postoperative recoveries were observed.Results:Both operations were successfully completed.The average operative time was 90 min and the average length of hospital stay was 15 days.No fevers,incision infections,intestinal obstruction,graft rejection,or other serious complications were noted.After 2 months,ure-teroscopic examinations showed that the surfaces of the original patches were covered by mu-Cosa and there were no apparent stenoses in the lumens.The ureteral stents were replaced every 2 months postoperatively and removed 12 months postoperatively.No infections or uri-nary leakage occurred after removal of the stents.Intravenous urography was performed 6 and 12 months postoperatively.The results showed that the ureters were not obstructed and there was no apparent stenosis at the anastomosis sites.The average follow-up time was>12 months.Long-term follow-up is still ongoing,and computed tomography examin ations of the urinary tract have been conducted in the outpatient department of our hospital 1,3,and 6 months after removal of the double-J stents,suggesting the absence of hydronephrosis.The serum creatinine levels remained stable during the follow-up.Conclusion:SIS matrix reconstruction is a feasible method to repair ureters stenosis.

A Polyp Detection Method Based on FBnet

The incidence of colorectal cancer(CRC)in China has increased in recent years.The mortality rate of CRC has become one of the highest among all cancers;CRC increasingly affects the health and quality of people’s lives.However,due to the insufficiency of medical resources in China,the workload on medical doctors has further increased.In the past few decades,the adult CRC mortality and morbidity rate dropped sharply,mainly because of CRC screening and removal of adenomatous polyps.However,due to the differences in polyp itself and the skills of endoscopists,the detection rate of polyps varies greatly.In this paper,we adopt an anchor-free mechanism and introduce a better method to factorize the process of bounding box regression.Firstly,we regress the shape of object by the variant of Faster RCNN.Secondly,we re-define the target function of the location of object.The experimental result shows that our method achieves a mAP of 55.8%,which outperforms other state-of-the-art methods by at least 11.9%.This will greatly help to reduce the missed diagnosis of clinicians during endoscopy and treatment,and provide effective help for early diagnosis,early treatment and prevention of CRC.

Air Quality Prediction Based on Kohonen Clustering and ReliefF Feature Selection

Air quality prediction is an important part of environmental governance.The accuracy of the air quality prediction also affects the planning of people’s outdoor activities.How to mine effective information from historical data of air pollution and reduce unimportant factors to predict the law of pollution change is of great significance for pollution prevention,pollution control and pollution early warning.In this paper,we take into account that there are different trends in air pollutants and that different climatic factors have different effects on air pollutants.Firstly,the data of air pollutants in different cities are collected by a sliding window technology,and the data of different cities in the sliding window are clustered by Kohonen method to find the same tends in air pollutants.On this basis,combined with the weather data,we use the ReliefF method to extract the characteristics of climate factors that helpful for prediction.Finally,different types of air pollutants and corresponding extracted the characteristics of climate factors are used to train different sub models.The experimental results of different algorithms with different air pollutants show that this method not only improves the accuracy of air quality prediction,but also improves the operation efficiency.

ClSnRK2.3 negatively regulates watermelon fruit ripening and sugar accumulation

Watermelon(Citrullus lanatus) as non-climacteric fruit is domesticated from the ancestors with inedible fruits. We previously revealed that the abscisic acid(ABA) signaling pathway gene ClSnRK2.3 might infuence watermelon fruit ripening. However,the molecular mechanisms are unclear. Here,we found that the selective variation of ClSnRK2.3 resulted in lower promoter activity and gene expression level in cultivated watermelons than ancestors, which indicated ClSnRK2.3 might be a negative regulator in fruit ripening. Overexpression (OE) of ClSnRK2.3 significantly delayed watermelon fruit ripening and suppressed the accumulation of sucrose, ABA and gibberellin GA4. Furthermore,we determined that the pyrophosphate-dependent phosphofructokinase(ClPFP1) in sugar metabolism pathway and GA biosynthesis enzyme GA20 oxidase(Cl GA20ox) could be phosphorylated by ClSnRK2.3 and thereby resulting in accelerated protein degradation in OE lines and finally led to low levels of sucrose and GA4. Besides that, ClSnRK2.3 phosphorylated homeodomain-leucine zipper protein(ClHAT1) and protected it from degradation to suppress the expression of the ABA biosynthesis gene 9’-cis-epoxycarotenoid dioxygenase 3(Cl NCED3). These results indicated that ClSnRK2.3 negatively regulated watermelon fruit ripening by manipulating the biosynthesis of sucrose, ABA and GA4. Altogether, these findings revealed a novel regulatory mechanism in non-climacteric fruit development and ripening.

Bionic design and performance test of maize grain cleaning screen through earthworm motion characteristics

The maize mixture feeding with a large mass cannot be migrated backward rapidly along the planar reciprocating vibrating screen,and it is easy to accumulate in the front of the screen,which leads to the decrease of screening efficiency.Based on the reverse engineering technology,using the wavy geometry formed during the earthworm(Pheretima guillelmi)moving as a bionic prototype,a bionic screen was designed to make the maize mixture migrate backward rapidly in the front of the screen.The contour curve of earthworm’s head in an axial contracted state was extracted and fitted to obtain its equation.Based on the difference of concave position of the lower surface’s wavy geometry during the earthworm moving,the motion of the bionic screen was divided into four postures,and the conversion between different postures of the bionic screen was realized by the cam drive mechanism.The kinematics simulation of the bionic screen was carried out through ADAMS,and the displacement and velocity of the bionic screen were analyzed.When the feeding mass of the maize mixture was set at 5 kg/s,6 kg/s and 7 kg/s,the test results showed that the time of the maize mixture migrated(TOMMM)in the front of the bionic screen was shortened by 0.18 s,0.71 s,and 1.36 s,respectively,compared with that of planar reciprocating vibrating screen.The total screening time(TST)of the bionic screen was shortened by 1.28 s,1.33 s,and 1.53 s,respectively.The ability of the maize mixture to be migrated backward was improved.This study can provide a reference for the innovative design of the cleaning screen.

Natural variation in the NAC transcription factor NONRIPENING contributes to melon fruit ripening

ThThe NAC transcription factor NONRIPENING(NOR)is a master regulator of climacteric fruit ripening.Melon(Cucumis melo L.)has climacteric and nonclimacteric fruit ripening varieties and is an ideal model to study fruit ripening.Two natural CmNAC-NOR variants,the climacteric haplotype CmNAC-NOR^(S,N) and the non-climacteric haplotype CmNAC-NOR^(A,S),have effects on fruit ripening;however,their regulatory mechanisms have not been elucidated.Here,we report that a natural mutation in the transcriptional activation domain of CmNAC-NORS,Ncontributes to climacteric melon fruit ripening.CmNAC-NOR knockout in the climacteric-type melon cultivar“BYJH”completely inhibited fruit ripening,while ripening was delayed by 5-8 d in heterozygous cmnac-nor mutant fruits.CmN AC-NOR directly activated carotenoid,ethylene,and abscisic acid biosynthetic genes to promote fruit coloration and ripening.Furthermore,CmNAC-NOR mediated the transcription of the“CmNAC-NOR-CmNAC73-CmCWINV2”module to enhance flesh sweetness.The transcriptional activation activity of the climacteric haplotype CmNAC-NORS,Non these target genes was significantly higher than that of the nonclimacteric haplotype CmNAC-NOR^(A,S).Moreover,CmNAC-NORS,Ncomplementation fully rescued the non-ripening phenotype of the tomato(Solanum lycopersicum)cr-nor mutant,while CmNAC-NOR^(A,S) did not.Our results provide insight into the molecular mechanism of climacteric and non-climacteric fruit ripening in melon.