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Exact satisfiability and phase transition analysis of the regular(k,d)-CNF formula

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Frontiers of Computer Science 2024年第1期18卷 263-265页

作者： Guoxia nie Daoyun XU xi WANG Zaijun ZHANG College of Computer Science and Technology Guizhou UniversityGuiyang 550025China School of Mathematics and Statistics Qiannan Normal University for NationalitiesDuyun 558000China Key Laboratory of Industrial Automation and Machine Vision of Qiannan Duyun 558000China

1Introduction The satisfiability(SAT)problem has been considered the"seed"of other NP-complete *** regular partial exact(k,d)-SAT problem is an important extension of the SAT *** any(k,d)-CNF formula with a variable set V,V'is a proper subset of V,the problem involves determining whether a truth assignment set on V'exists such that only a literal in each clause is *** V'=V,it is a regular exact(k,d)-SAT ***,both experimental verifications and theoretical analyses of k-SAT problem have shown that the ratioα(clause constraint density)of the number of clauses m to the number of variables n is an important parameter affecting the satisfiability of the formula[1].However,the regular(k,d)-SAT problem has the same clause constraint density d/k.

关键词： formula constraint exact

Quantification of Trace Amounts of Impurities in High Purity Cobalt by High Resolution Inductively Coupled Plasma Mass Spectrometry

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Chinese Chemical Letters 2006年第8期17卷 1077-1080页

作者： Hua Lin xiE xi du nie You Gen TANG Department of Chemistry Hunan Institute of Technology Hengyang 421008 School of Chemistry and Chemical Engineering Central south university Changsha 410083

An analytical method using high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS） for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results.

关键词： High resolution inductively coupled plasma mass spectrometry high purity cobalt,trace impurities matrix effect spectral interference internal standards.

Matrix Effects and Behaviors of Elements in Oxalic Acid Medium by Inductively Coupled Plasma Mass Spectrometry

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Chinese Chemical Letters 2006年第7期17卷 945-948页

作者： Hua Lin xiE Yu Jie LI xi du nie Li Bo LI Department of Chemistry Hunan Institute of Technology Hengyang 421008 College of Chemistry and Chemical Engineering Central south University Changsha 410083

The influence of different concentration of oxalic acid matrix on elemental inductively coupled plasma mass spectrometry （ICP-MS） has been investigated. It has been proved that the sensitivity of analytes can be significantly enhanced by adding small amounts of oxalic acid medium with adjusted nebulizer flow-rate gas, especially for the elements with ionization potential between 9 and 11 eV. Oxalic acid, as an enhancement agent, can be used to compensate the signal depression caused by inorganic matrix and to improve the detection limits about two to eight times, for the hard-to-ionize elements in ICP-MS determination.

关键词： ICP-MS oxalic acid enhancement effect.

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang Zhen-yuan nie Hong-chang Liu Yue Liu Can Wang Jin-lan xia Wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

Clinical manifestations and spermatogenesis outcomes in Chinese patients with congenital hypogonadotropic hypogonadism caused by inherited or de novo FGFR1 mutations

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Asian Journal of Andrology 2024年第4期26卷 426-432页

作者： Yu-Fan Yang Hai-Lu Ma xi Wang Min nie Jiang-Feng Mao Xue-Yan Wu Department of Endocrinology Peking Union Medical College HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100730China.

Fibroblast growth factor receptor 1(FGFR1)mutations are associated with congenital hypogonadotropic hypogonadism(CHH)through inheritance or spontaneous *** detected FGFR1 mutations in a Chinese cohort of 210 CHH patients at Peking Union Medical College Hospital(Beijing,China)using next-generation and Sanger *** assessed missense variant pathogenicity using six bioinformatics tools and compared clinical features and treatment outcomes between inherited and de novo mutation *** 19 patients with FGFR1 mutations,three were recurrent,and 16 were novel *** of the novel mutations were likely pathogenic according to the American College of Medical Genetics and Genomics(ACMG)guidelines,with the prevalent P366L *** majority of FGFR1 mutations was inherited(57.9%),with frameshift mutations exclusive to the de novo mutation *** inherited mutation group had a lower incidence of cryptorchidism,short stature,and skeletal *** the inherited mutation group,luteinizing hormone(LH)levels were 0.5 IU l−1,follicle-stimulating hormone(FSH)levels were 1.0 IU l−1,and testosterone levels were 1.3 nmol l−*** contrast,the de novo group had LH levels of 0.2 IU l−1,FSH levels of 0.5 IU l−1,and testosterone levels of 0.9 nmol l−1,indicating milder hypothalamus–pituitary–gonadal axis(HPGA)functional deficiency in the inherited *** inherited mutation group showed a tendency toward higher spermatogenesis *** conclusion,this study underscores the predominance of inherited FGFR1 mutations and their association with milder HPGA dysfunction compared to de novo mutations,contributing to our understanding of the genetic and clinical aspects of FGFR1 mutations.

关键词： congenital hypogonadotropic hypogonadism de novo FGFR1 inherited

Mechanism of Qili Qiangxin Capsule for Heart Failure Based on miR133a-Endoplasmic Reticulum Stress

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Chinese Journal of Integrative Medicine 2024年第5期30卷 398-407页

作者： JI xiao-di YANG Ding CUI xi-yuan LOU Li-xia nie Bo ZHAO Jiu-li ZHAO Ming-jing WU Ai-ming Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine Key Laboratory of Chinese Internal Medicine of Ministry of Education and BeijingBeijing 100700China Department of Traditional Chinese Medicine Fuwai HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100037China

Objective:To investigate the pharmacological mechanism of Qili Qiangxin Capsule(QLQX)improvement of heart failure(HF)based on miR133a-endoplasmic reticulum stress(ERS)***:A left coronary artery ligation-induced HF after myocardial infarction model was used in this *** were randomly assigned to the sham group,the model group,the QLQX group[0.32 g/(kg·d)],and the captopril group[2.25 mg/(kg·d)],15 rats per group,followed by 4 weeks of *** function such as left ventricular ejection fraction(EF),fractional shortening(FS),left ventricular systolic pressure(LVSP),left ventricular end diastolic pressure(LVEDP),the maximal rate of increase of left ventricular pressure(+dp/dt max),and the maximal rate of decrease of left ventricular pressure(–dp/dt max)were monitored by echocardiography and *** and eosin(HE)and Masson stainings were used to visualize pathological changes in myocardial *** m RNA expression of mi R133a,glucose-regulated protein78(GRP78),inositol-requiring enzyme 1(IRE1),activating transcription factor 6(ATF6),X-box binding protein1(XBP1),C/EBP homologous protein(CHOP)and Caspase 12 were detected by *** protein expression of GRP78,p-IRE1/IRE1ratio,cleaved-ATF6,XBP1-s(the spliced form of XBP1),CHOP and Caspase 12 were detected by Western *** T-mediated d UTP nick-end labeling(TUNEL)staining was used to detect the rate of ***:QLQX significantly improved cardiac function as evidenced by increased EF,FS,LVSP,+dp/dt max,-dp/dt max,and decreased LVEDP(Pduced collagen volume fraction in myocardial tissue(P<0.01).Results from RT-PCR and Western blot showed that QLQX significantly increased the expression of mi R133a and inhibited the m RNA expressions of GRP78,IRE1,ATF6 and XBP1,as well as decreased the protein expressions of GRP78,cleave

关键词： heart failure Qili Qiangxin Capsule miR133a endoplasmic reticulum stress apoptosis

Giant cavernous aneurysms occluded by aneurysmal thrombosis,calcification,parent artery occlusion:A case report and review of literature

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World Journal of Clinical Cases 2024年第16期12卷 2822-2830页

作者： Ming-xi Wang Qing-Bin nie School of Medicine Huaqiao UniversityXiamen 361021Fujian ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijing 100853China

BACKGROUND Patients with giant intracranial aneurysms(GIAs)are at a high risk of rupture,morbidity,and mortality even after surgical or endovascular *** described a case of a spontaneously occluded GIA secondary to gradual growth of the GIA,continuously progressed aneurysmal thrombosis,complete aneurysmal calcification and complete occlusion of the parent artery-the right internal carotid artery(RICA).CASE SUMMARY A 72-year-old female patient complained of sudden pain in her right eye upon admission to our *** had been diagnosed with a GIA[30 mm(axial)×38 mm(coronal)×28 mm(sagittal)]containing an aneurysmal thrombus located in the cavernous sinus segment of RICA diagnosed by magnetic resonance imaging(MRI),enhanced MRI,and magnetic resonance angiography more than 14 years ***,with slow growth of the cavernous carotid GIA,aneurysmal thrombosis progressed continuously,spontaneous occlusion of the RICA,complete aneurysmal calcification,and occlusion of the GIA occurred *** had no history of subarachnoid hemorrhage but missed the chance for endovascular therapy at an early *** a result,she was left with severe permanent sequelae from the injuries to the right cranial nerves Ⅱ,Ⅲ,Ⅳ,V1/V2,and Ⅴ.CONCLUSION The risk of rupture of the cavernous carotid GIAs was relatively low and possibly further be reduced by the stasis flow and spontaneous occlusion of the parent artery internal carotid artery(ICA)induced by the mass effect of the cavernous carotid GIAs and the extremely rare aneurysmal ***,nowadays,it is advisable to recommend early endovascular treatment for the cavernous carotid GIAs to prevent injuries to the surrounding intracranial nerves and occlusion of the ICA,mainly caused by the mass effect of the cavernous carotid GIAs.

关键词： Giant intracranial aneurysm Cavernous sinus Aneurysmal thrombosis and calcification Spontaneous occlusion of the parent artery Conservative therapy Case report

Fluid-structure interaction simulation for multi-body flexible morphing structures

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Chinese Journal of Aeronautics 2024年第2期37卷 137-147页

作者： Wenzhi GUO Yongtao SHUI Lu nie Gang CHEN State Key Laboratory of Strength and Vibration for Mechanic Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Launch Vehicle Technology Beijing 100076China China Academy of Aerospace Science and Innovation Beijing 100086China Shannxi Key Laboratory of Service Environment and Control for Flight Vehicles Xi’an Jiaotong UniversityXi’an 710049China

The multi-body flexible morphing airfoil can improve the aerodynamic characteristics based on different flight missions *** researches have focused on the unsteady aerodynamic characteristics of flexible wings under passive ***,the unsteady aerodynamic characteristics with the fluid-structure interaction effects in the multi-body active actuation process of morphing airfoil deserve further *** this paper,a fluid-structure coupled simulation method for multi-body flexible morphing airfoil with active actuation subsystem was investigated,and the aerodynamic characteristics during deformation were compared with different skin flexibility,flow field environment,actuation mode and actuation *** numerical results show that for the steady aerodynamic,the skin flexibility can improve the stability *** the unsteady process,the change trend of the transient lift coefficient and pitching moment are consistent with those of the active drive characteristics,while the instantaneous lift-drag ratio coefficient is greatly affected by the driving mode and can be improved by increasing the driving duration.

关键词： Fluid-structure interaction Multi-body dynamics modeling Flexible structures Aerodynamics Morphing wings

A reduced-order model for fast predicting ionized flows of hypersonic vehicles along flight trajectory

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Chinese Journal of Aeronautics 2024年第1期37卷 89-105页

作者： Jingchao ZHANG Chunsheng nie Jinsheng CAI Shucheng PAN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

An improved Reduced-Order Model(ROM)is proposed based on a flow-solution preprocessing operation and a fast sampling strategy to efficiently and accurately predict ionized hypersonic *** ROM is generated in low-dimensional space by performing the Proper Orthogonal Decomposition(POD)on snapshots and is coupled with the Radial Basis Function(RBF)to achieve fast prediction ***,due to the disparate scales in the ionized flow field,the conventional ROM usually generates spurious negative ***,this issue is addressed by performing flow-solution preprocessing in logarithmic space to improve the conventional ***,extra orthogonal polynomials are introduced in the RBF interpolation to achieve additional improvement of the prediction *** addition,to construct high-efficiency snapshots,a trajectory-constrained adaptive sampling strategy based on convex hull optimization is *** evaluate the performance of the proposed fast prediction method,two hypersonic vehicles with classic configurations,i.e.a wave-rider and a reentry capsule,are used to validate the proposed *** two cases show that the proposed fast prediction method has high accuracy near the vehicle surface and the free-stream region where the flow field is *** with the conventional ROM prediction,the prediction results are significantly improved by the proposed method around the discontinuities,*** shock wave and the ionized *** a result,the proposed fast prediction method reduces the error of the conventional ROM by at least 45%,with a speedup of approximately 2.0×105compared to the Computational Fluid Dynamic(CFD)*** test cases demonstrate that the method developed here is efficient and accurate for predicting ionized hypersonic flows.

关键词： Reduced-order model Radial basis function Constrained sampling Transfer function Fast flow prediction Ionized hypersonic flows