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A novel stellar spectrum denoising method based on deep Bayesian modeling

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Research in Astronomy and Astrophysics 2021年第7期21卷 127-142页

作者： Xin Kang Shi-yuan he Yan-Xia Zhang Institute of Statistics and Big Data Renmin University of ChinaBeijing 100872China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesBeijing 100101China

Spectrum denoising is an important procedure for large-scale spectroscopical surveys. This work proposes a novel stellar spectrum denoising method based on deep Bayesian modeling. The construction of our model includes a prior distribution for each stellar subclass, a spectrum generator and a flow-based noise model. Our method takes into account the noise correlation structure, and it is not susceptible to strong sky emission lines and cosmic rays. Moreover, it is able to naturally handle spectra with missing flux values without ad-hoc imputation. The proposed method is evaluated on real stellar spectra from the Sloan Digital Sky Survey(SDSS) with a comprehensive list of common stellar subclasses and compared to the standard denoising auto-encoder. Our denoising method demonstrates a superior performance to the standard denoising auto-encoder, in respect of denoising quality and missing flux imputation. It may be potentially helpful in improving the accuracy of the classification and physical parameter measurement of stars when applying our method during data preprocessing.

关键词： methods:data analysis methods:numerical methods:statistical techniques:spectroscopic

heterozygosity of Knob-Associated Tandem Repeats and Knob Instability in Mitotic Chromosomes of Zea （Zea mays L. and Z. diploperennis Iltis Doebley）

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Journal of Integrative Plant Biology 2005年第11期47卷 1345-1351页

作者： Zhi-Yong XIONG Yong LIU Yong-Gang he Yun-Chun SONG Ke-Xiu LI Guan-yuan he China-UK HUST-RRes （Rothamsted Reseach UK） Genetic Engineering and Genomics Joint Laboratory Huazhong University of Science and Technology （HUST） Wuhan 430074 China Key Laboratory of the Ministry of Education for Plant Developmental Biology Wuhan University Wuhan 430072 China

Knobs are blocks of heterochromatin present on chromosomes of maize （Zea mays L.） and its relatives that have effects on the frequency of genetic recombination, as well as on chromosome behavior. Knob heterozygosity and instability in six maize inbred lines and one Z. diploperennis Iltis Doebley line were investigated using the fluorescence in situ hybridization （FISH） technique with knob-associated tandem repeats （180 bp and 350 bp （TR- 1）） as probes. Signals of seven heterozygous knobs containing 180- bp repeats and of one heterozygous knob containing TR- 1 were captured in chromosomes of all materials tested according to the results of FISH, which demonstrates that the 180-bp repeat is the main contributor to knob heterozygosity compared with the TR- 1 element. In addition, one target cell with two TR- 1 signals on one homolog of chromosome 2L, which was different from the normal cells in the maize inbred line GB57, was observed, suggesting knob duplication and an instability phenomenon in the maize genome.

关键词： fluorescence in situ hybridization knob repetitive DNA sequence Zea diploperennis Z. mays.

Some Recursion Formulae for the Number of Derangements and Bell Numbers

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Journal of Mathematical Research with Applications 2016年第1期36卷 15-22页

作者： yuan he Jing PAN Faculty of Science Kunming University of Science and Technology

In this paper, a further investigation for the number of Derangements and Bell numbers is performed, and some new recursion formulae for the number of Derangements and Bell numbers are established by applying the generating function methods and Padé approximation techniques. Illustrative special cases of the main results are also presented.

关键词： the number of Derangements Bell numbers Padé approximants recursion formulae

Study of screening,transport pathway,and vasodilation mechanisms on angiotensin-Ⅰconverting enzyme inhibitory peptide from Ulva prolifera proteins

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Acta Oceanologica Sinica 2023年第11期42卷 98-106页

作者： Zhiyong Li yuan he Hongyan he Caiwei Fu Mengru Li Aiming Lu Dongren Zhang Tuanjie Che Songdong Shen School of Biology&Basic Medical Sciences Soochow UniversitySuzhou 215101China Key Laboratory of Functional Genomic and Molecular Diagnosis of Gansu Province Lanzhou 730030China

In this study,Ulva prolifera protein was used for preparing angiotensin-I converting enzyme(ACE)-inhibitory peptide via virtual gastrointestinal digestion and in silico *** parameters of the obtained peptide,such as inhibition kinetics,docking mechanism,stability,transport pathway,were explored by Lineweaver-Burk plots,molecular docking,in vitro stimulate gastrointestinal(GI)digestion and Caco-2 cells monolayer model,***,a novel anti-ACE peptide LDF(IC_(50),(1.66±0.34)μmol/L)was screened and synthesized by chemical *** was a no-competitive inhibitor and its anti-ACE inhibitory effect mainly attributable to four Conventional Hydrogen Bonds and Zn701 *** could keep activity during simulated GI digestion in vitro and was transported by peptide transporter PepT1 and passive-mediated ***,it could activate Endothelial nitric oxide synthase(eNOS)activity to promote the production of NO and reduce Endothelin-1(ET-1)secretion induced by AngiotensinⅡ(AngⅡ)in Human Umbilical Vein Endothelial Cells(HUVECs).Meanwhile,it could promote mice splenocytes proliferation in a concentration-dependent *** study indicated that this peptide was a potential ingredient functioning on vasodilation and enhancing immunity.

关键词： Ulva prolifera protein ACE-inhibitory peptide in vitro GI digestion vasodilation mechanism immunomodulation

Bilinear Forms and Dark-Dark Solitons for the Coupled Cubic-Quintic Nonlinear Schrodinger Equations with Variable Coefficients in a Twin-Core Optical Fiber or Non-Kerr Medium

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Communications in Theoretical Physics 2019年第12期71卷 1393-1398页

作者： Mei-Xia Chu Bo Tian Yu-Qiang yuan Ze Zhang he-yuan Tian State Key Laboratory of Information Photonics and Optical Communications and School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Twin-core optical fibers are applied in such fields as the optical sensing and optical communication,and propagation of the pulses,Gauss beams and laser beams in the non-Kerr media is *** in this paper are the coupled cubic-quintic nonlinear Schrodinger equations with variable coefficients,which describe the effects of quintic nonlinearity for the ultrashort optical pulse propagation in a twin-core optical fiber or non-Kerr *** on the integrable conditions,bilinear forms are derived,and dark-dark soliton solutions can be constructed in terms of the Gramian via the Kadomtsev-Petviashvili hierarchy *** and interaction of the dark-dark solitons are presented and discussed through the graphic *** different values of the delayed nonlinear response effect b(z),where z represents direction of the propagation,the linear-and parabolic-shaped one dark-dark soltions can be *** between the parabolic-and periodic-shaped two dark-dark solitons are presented with b(z)as the linear and periodic functions,*** of velocities of the two dark-dark solitons vary with z and the amplitudes of the solitons remain unchanged can be *** between the two dark-dark solitons of different types are displayed,and we observe that the velocity of one soliton is zero and direction of the velocity of the other soliton vary with *** find that those interactions are elastic.

关键词： optical fiber coupled cubic-quintic nonlinear Schrodinger equations dark-dark solitons Kadomtsev-Petviashvili hierarchy reduction

Multi-frequency point supported LLRF front-end for CiADS wide-bandwidth application

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Nuclear Science and Techniques 2020年第3期31卷 66-73页

作者： Qi Chen Zheng Gao Zheng-Long Zhu Zong-heng Xue yuan he Xian-Wu Wang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The China initiative Accelerator Driven System,CiADS,physics design adopts 162.5 MHz,325 MHz,and 650 MHz cavities,which are driven by the corresponding radio frequency(RF)power system,requiring frequency translation front-end for the RF *** that application,a general-purpose design front-end prototype has been developed to evaluate the multi-frequency point supported design *** difficult parts to achieve the requirements of the general-purpose design are reasonable device selection and balanced *** a carefully selected low-noise wide-band RF mixer and amplifier to balance the performance of multi-frequency supported down-conversion,specially designed LO distribution net to increase isolation between adjacent channels,and external band-pass filter to realize expected up-conversion frequencies,high maintenance and modular front-end generalpurpose design has been *** of standard parameters show an R2 value of at least 99.991%in the range of-60-10 dBm for linearity,up to 18 dBm for P1dB,and up to 89 dBc for cross talk between adjacent *** phase noise spectrum is lower than 80 dBc in the range of 0-1 MHz;cumulative phase noise is 0.006°;and amplitude and phase stability are 0.022%and 0.034°,respectively.

关键词： Frequency jump RF Front-end LLRF CiADS

Novel invagination procedure for pancreaticojejunostomy using double purse string sutures:A technical note

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World Journal of Gastrointestinal Surgery 2023年第12期15卷 2792-2798页

作者： Jun Li he-yuan Niu Xing-Kai Meng Department of hepatobiliary Pancreatic and Splenic SurgeryThe Affiliated Hospital of Inner Mongolia Medical UniversityHohhot 010010Inner Mongolia Autonomous RegionChina

BACKGROUND Postoperative pancreatic fistula(POPF)is one of the most serious complications after pancreaticoduodenectomy(PD),and the choice of pancreaticojejunostomy(PJ)is considered a key factor affecting the occurrence of *** anastomotic methods and their modifications have been proposed,and there is no method that can completely avoid the occurrence of *** on our team’s experience in pancreatic surgery and a review of relevant literature,we describe a novel invagination procedure for PJ using double purse string sutures,which has resulted in favourable *** To describe the precise procedural steps,technical details and clinical efficacy of the novel invagination procedure for *** This study adopted a single-arm retrospective cohort study methodology,involving a total of 65 consecutive patients who underwent PD with the novel invagination procedure for PJ,including the placement of a pancreatic stent,closure of the residual pancreatic end,and two layers of purse-string *** data included age,sex,body mass index(BMI),pancreatic texture,pancreatic duct diameter,operation time,and blood *** outcomes included the operation time,blood loss,and incidence of POPF,postoperative haemorrhage,delayed gastric emptying,postoperative pulmonary infection,postoperative abdominal infection,and postoperative pulmonary *** The mean age of the patients was 59.12(±8.08)*** males and 25 females were included,and the mean BMI was 21.61 kg/m^(2)(±2.74).A total of 41.53% of patients had a pancreatic duct diameter of 3 mm or *** mean operation time was 263.83 min(±59.46),and the mean blood loss volume was 318.4 mL(±163.50).Following the surgical intervention,only three patients showed grade B POPF(4.62%),while no patients showed grade C *** patients(5/65,7.69%)were diagnosed with postoperative *** patients(6/65,9.23%)experienced delayed gastric *** patients(4/65,6.15%)developed post

关键词： Pancreatic anastomosis Pancreatojejunostomy Pancreatic fistula

Synonymous Codon Usage Bias and Overexpression of a Synthetic Gene Encoding Interferon α2b in Yeast

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中国病毒学 2007年第3期22卷 226-232页

作者： Bin FANG　 Bu-feng LIANG　 Guang-yuan he China-UK HUST-RRes Genetic Engineering and Genomics Joint Lab Huazhong University of Science and Technology （HUST） Wuhan 430074 China Joint R＆D Lab （Suzhong Pharma Co. Ltd） IHS Wuhan Institute of Virology Chinese Academy of Sciences Wuhan 430071 China

To achieve higher level expression of Interferon α2b(IFN-α2b)in methylotrophic yeast(Pichia pastoris),a cDNA fragment coding for the mature IFN-α2b was designed and synthesized based on the synonymous codon bias of *** and optimized G+C *** synthetic IFN-α2b was inserted into the secreted expression vector pPICZαA,and then integrated into *** GS115 genome by ***-copy integrants in the Mut+ recombinant *** strain were screened by high concentrations of Zeocin.120 hours culturing allowed expression of the IFN-α2b transformant up to 810 mg/L as detected by SDS-PAGE and quantitative *** addition,Western blot analysis showed that the recombinant proteins had *** significant antiviral activity of the recombinant IFN-α2b protein was verified by WISH/VSV system,which was 3.3×105 IU/mL.

关键词：酵母菌干扰素-α2b 同义密码子基因表达过表达

Mixed-mode fracture behavior in deep shale reservoirs under different loading rates and temperatures

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Petroleum Science 2023年第5期20卷 3037-3047页

作者： Yu Suo Yan-Jie Zhao Xiao-Fei Fu Wen-yuan he Zhe-Jun Pan School of Petroleum Engineering Northeast Petroleum UniversityDaqing163318HeilongjiangChina Postdoctoral Resource Center Daqing Oilfield Company LimitedDaqing163458HeilongjiangChina Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development(Northeast Petroleum University) Ministry of EducationDaqing163318HeilongjiangChina heilongjiang Province Key Laboratory of Oil and Gas Reservoir Fracturing and Evaluation Daqing163318HeilongjiangChina PetroChina International Exploration and Development Company Limited Corporation Beijing100034China

In the last years,shale gas has gradually substituted oil and coal as the main sources of energy in the *** with shallow shale gas reservoirs,deep shale is characterized by low permeability,low porosity,strong heterogeneity,and strong *** the process of multi-cluster fracturing of horizontal wells,the whole deformation process and destruction modes are significantly influenced by loading *** this investigation,the servo press was used to carry out semi-circular bend(SCB)mixedmode fracture experiments in deep shales(130,160,190℃)with prefabricated fractures under different loading rates(0.02,0.05,0.1,0.2 mm/min).The fracture propagation process was monitored using acoustic *** deformation characteristics,displacementeload curve,and acoustic emission parameters of shale under different loading rates were studied during the mixed-mode fracture *** results showed that during the deformation and fracture of the specimen,the acoustic emission energy and charge significantly increased near the stress peak,showing at this point the most intense acoustic emission *** the increase in loading rate,the fracture peak load of the deep shale specimen also ***,the maximum displacement decreased to different *** the increase in temperature,the effective fracture toughness of the deep shale gradually ***,the maximum displacement *** different loading rates,the deformation of the prefabricated cracks showed a nonlinear slow growthelinear growth *** slope of the linear growth stage increased with the increase in loading *** addition,as the loading rate increased,an increase in tension failure and a decrease in shear failure were ***,the control chart showing the relationship between tension and the shear failure under different temperatures and loading rates was determined.

关键词： Deep shale Mixed-mode fracture toughness Loading rate Deformation characteristics