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Primordial black hole mass functions as a probe of cosmic origin

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： yi-fu cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce cosmology.The standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from PBHs.We demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic origin.Additionally,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： Jin-yi cai College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor's algorithm rotation gates quantum computing prime factorization

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Comparison of prognosis and postoperative morbidities between standard pancreaticoduodenectomy and the TRIANGLE technique for resectable pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 689-699页

作者： He-Xing Hang Zheng-Hua cai yi-Fei Yang Xu fu Yu-Dong Qiu Hao Cheng Division of Pancreatic Surgery Department of General SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina

BACKGROUND Radical surgery combined with systemic chemotherapy offers the possibility of long-term survival or even cure for patients with pancreatic ductal adenocar-cinoma(PDAC),although tumor recurrence,especially locally,still inhibits the treatment efficacy.The TRIANGLE technique was introduced as an extended dissection procedure to improve the R0 resection rate of borderline resectable or locally advanced PDAC.However,there was a lack of studies concerning postoperative complications and long-term outcomes of this procedure on patients with resectable PDAC.PDAC.METHODS Patients with resectable PDAC eligible for PD from our hospital between June 2018 and December 2021 were enrolled in this retrospective cohort study.All the patients were divided into PDstandard and PDTRIANGLE groups according to the surgical procedure.Baseline characteristics,surgical data,and postoperative morbidities were recorded.All of the patients were followed up,and the date and location of tumor recurrence,and death were recorded.The Kaplan-Meier method and log-rank test were used for the survival analysis.RESULTS There were 93 patients included in the study and 37 underwent the TRIANGLE technique.Duration of operation was longer in the PDTRIANGLE group compared with the PDstandard group[440(410-480)min vs 320(265-427)min](P=0.001).Intraoperative blood loss[700(500-1200)mL vs 500(300-800)mL](P=0.009)and blood transfusion[975(0-1250)mL vs 400(0-800)mL](P=0.009)were higher in the PDTRIANGLE group.There was a higher incidence of surgical site infection(43.2%vs 12.5%)(P=0.001)and postoperative diarrhea(54.1%vs 12.5%)(P=0.001)in the PDTRIANGLE group.The rates of R0 resection and local recurrence,overall survival,and disease-free survival did not differ significantly between the two groups.CONCLUSION The TRIANGLE technique is safe,with acceptable postoperative morbidities compared with standardized PD,but it does not improve prognosis for patients with resectable PDAC.

关键词： Pancreatic ductal adenocarcinoma TRIANGLE technique Pancreaticoduodenectomy Prognosis Postoperative morbidities

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N-Heterocyclic carbene-catalyzed enantioselective(dynamic) kinetic resolutions and desymmetrizations

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Science China Chemistry 2024年第2期67卷 482-511页

作者： yi Zhang Hui cai Xiuhai Gan Zhichao Jin National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityHuaxi DistrictGuiyang550025China

N-heterocyclic carbene-catalyzed enantioselective kinetic resolutions,dynamic kinetic resolutions,and desymmetrization reactions are systematically reviewed.The content is organized according to the activation modes involved in these transformations.future advances within this highly active research field are discussed from our perspectives on the topic.

关键词： N-heterocyclic carbene kinetic resolution dynamic kinetic resolution desymmetrization organocatalysis

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Digital twin modeling and controlling of optical power evolution enabling autonomous-driving optical networks:a Bayesian approach

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Advanced Photonics 2024年第2期6卷 69-80页

作者： Xiaomin Liu yihao Zhang Yuli Chen yichen Liu Meng cai Qizhi Qiu Mengfan fu Lilin yi Weisheng Hu Qunbi Zhuge Shanghai Jiao Tong University State Key Laboratory of Advanced Optical Communication Systems and NetworksDepartment of Electronic EngineeringShanghaiChina

Optical networks are evolving toward ultrawide bandwidth and autonomous operation.In this scenario,it is crucial to accurately model and control optical power evolutions(OPEs)through optical amplifiers(OAs),as they directly affect the signal-to-noise ratio and fiber nonlinearities.However,a fundamental contradiction arises between the complex physical phenomena in optical transmission and the required precision in network control.Traditional theoretical methods underperform due to ideal assumptions,while data-driven approaches entail exorbitant costs associated with acquiring massive amounts of data to achieve the desired level of accuracy.In this work,we propose a Bayesian inference framework(BIF)to construct the digital twin of OAs and control OPE in a data-efficient manner.Only the informative data are collected to balance the exploration and exploitation of the data space,thus enabling efficient autonomous-driving optical networks(ADONs).Simulations and experiments demonstrate that the BIF can reduce the data size for modeling erbium-doped fiber amplifiers by 80%and Raman amplifiers by 60%.Within 30 iterations,the optimal controlling performance can be achieved to realize target signal/gain profiles in links with different types of OAs.The results show that the BIF paves the way to accurately model and control OPE for future ADONs.

关键词： optical fiber communications digital twin Bayesian inference optical amplifiers autonomous-driving optical networks

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Graphitic carbon nitride nanosheets mitigate cadmium toxicity in Glycine max L.by promoting cadmium retention in root and improving photosynthetic performance

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Journal of Environmental Sciences 2024年第5期139卷 543-555页

作者： Kai Xu Yunyu Guo Chenghua Xing Ronglong fu Bin Zou Rongchuan Liu Luyi cai Jianfang Yan Xi-Lin Wu Miaozhen cai College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China College of Agriculture Jinhua PolytechnicJinhua 321007China

Cadmium(Cd)pollution poses a serious threat to plant growth and yield.Nanomaterials have shown great application potential for alleviation of Cd toxicity to plants.In this study,we applied graphitic carbon nitride nanosheets(g-C_(3)N_(4)NSs)for alleviation of Cd-toxicity to soybean(Glycine max L.).The g-C_(3)N_(4)NSs supplementation significantly improved plant growth and reduced oxidative damage in the Cd-toxicated soybean seedlings through hydroponic culture.Particularly,the g-C_(3)N_(4)NSs dynamically regulated the root cell wall(RCW)components by increasing pectin content and modifying its demethylation via enhancing pectin methylesterase(PME)activity,therefore greatly enhanced stronger RCW-Cd retention(up to 82.8%)and reduced Cd migration to the shoot.Additionally,the g-C_(3)N_(4)NSs reversed the Cd-induced chlorosis,increased photosynthetic efficiency because of enhancement in F_v/F_mration,Y(Ⅱ)and sugars content.These results provide new insights into the alleviation of Cd toxicity to plants by g-C_(3)N_(4)NSs,and shed light on the application of low-cost and environmental-friendly carbon-based NMs for alleviating heavy metal toxicity to plants.

关键词： Cadmium Carbon nitride nanosheets Cell wall Pectin Pectin methylesterase Soybean

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Different lymph node staging systems for predicting the prognosis of colorectal neuroendocrine neoplasms

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1745-1755页

作者： Yuan-yi Zhang Yue-Wei cai Xia Zhang Department of Pathology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina Department of Emergency Zhaoqing Second People’s HospitalZhaoqing 526020Guangdong ProvinceChina Department of Pathology and Physiology Zhaoqing Medical CollegeZhaoqing 526020Guangdong ProvinceChina

BACKGROUND Colorectal neuroendocrine neoplasms(NENs)are a rare malignancy that primarily arises from the diffuse distribution of neuroendocrine cells in the colon and rectum.Previous studies have pointed out that the status of lymph node may be used to predict the prognosis.AIM To investigate the predictive values of lymph node ratio(LNR),positive lymph node(PLN),and log odds of PLNs(LODDS)staging systems on the prognosis of colorectal NENs treated surgically,and compare their predictive values.METHODS This cohort study included 895 patients with colorectal NENs treated surgically from the Surveillance,Epidemiology,and End Results database.The endpoint was mortality of patients with colorectal NENs treated surgically.X-tile software was utilized to identify most suitable thresholds for categorizing the LNR,PLN,and LODDS.Participants were selected in a random manner to form training and testing sets.The prognosis of surgically treating colorectal NENs was examined using multivariate cox analysis to assess the associations of LNR,PLN,and LODDS with the prognosis of colorectal NENs.C-index was used for assessing the predictive effectiveness.We conducted a subgroup analysis to explore the different lymph node staging systems’predictive values.RESULTS After adjusting all confounding factors,PLN,LNR and LODDS staging systems were linked with mortality in patients with colorectal NENs treated surgically(Pfurthermore,the area under the receiver operating characteristic curve values for LODDS staging system remained consistently higher than those of PLN or LNR,even at the 1-,2-,3-,4-,5-and 6-year follow-up periods.CONCLUSION LNR,PLN,and LODDS were found to significantly predict the prognosis of patients with colorectal NENs treated surgically.

关键词： Positive lymph node Lymph node ratio Log odds of positive lymph nodes Prognosis Colorectal neuroendocrine neoplasms

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Solvent transport dynamics and its effect on evolution of mechanical properties of nitrocellulose(NC)-based propellants under hot-air drying process

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Defence Technology（防务技术） 2024年第2期32卷 262-270页

作者： Enfa fu Mingjun yi Qianling Liu Zhenggang Xiao Key Laboratory of Special Energy Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094People's Republic of China

Appropriate drying process with optimized controlling of drying parameters plays a vital role in the improvement of the quality and performance of propellant products.However,few research on solvent transport dynamics within NC-based propellants was reported,and its effect on the evolution of mechanical properties was not interpreted yet.This study is conducted to gain a comprehensive understanding of hot-air drying for NC-based propellants and clarify the effect of temperature on solvent transport behavior and further the change of mechanical properties during drying.The drying kinetic curves show the drying time required is decreased but the steady solvent content is increased and the drying rate is obviously increased with the increase of hot-air temperatures,indicating hot-air temperatures have a significant effect on drying kinetics.A modified drying model was established,and results show it is more appropriate to describe solvent transport behavior within NC-based propellants.Moreover,two linear equations were established to exhibit the relationship between solvent content and its effect on the change of tensile properties,and the decrease of residual solvent content causes an obvious increase of tensile strength and tensile modulus of propellant products,indicating its mechanical properties can be partly improved by adjustment of residual solvent content.The outcomes can be used to clarify solvent transport mechanisms and optimize drying process parameters of double-based gun propellants.

关键词： Nitrocellulose-based propellants Solvent transport dynamics Mechanical properties Drying kinetics Effective solvent diffusion coefficient

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Nurse anesthetists’perceptions and experiences of managing emergence delirium:A qualitative study

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World Journal of Psychiatry 2024年第4期14卷 553-562页

作者： yi Xin fu-cai Lin Chen Huang Bin He Ya-Ling Yan Shuo Wang Guang-Ming Zhang Rui Li Wuxi Medical College Jiangnan UniversityWuxi 214122Jiangsu ProvinceChina Department of Anesthesiology Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China Department of Nursing Tongren Hospital Shanghai Jiao Tong University School of MedicineShanghai 200335China

BACKGROUND This study employs a descriptive phenomenological approach to investigate the challenges anesthesia nurses face in managing emergence delirium(ED),a common and complex postoperative complication in the post-anesthesia care unit.The role of nurses in managing ED is critical,yet research on their understanding and management strategies for ED is lacking.AIM To investigate anesthetic nurses’cognition and management experiences of ED in hopes of developing a standardized management protocol.METHODS This study employed a descriptive phenomenological approach from qualitative research methodologies.Purposeful sampling was utilized to select 12 anesthetic nurses from a tertiary hospital in Shanghai as research subjects.Semi-structured interviews were conducted,and the data were organized and analyzed using Colaizzi’s seven-step analysis method,from which the final themes were extracted.RESULTS After analyzing the interview content,four main themes and eight subthemes were distilled:Inefficient cognition hinders the identification of ED(conceptual ambiguity,empirical identification),managing diversity and challenges(patientcentered safe care,low level of medical-nursing collaboration),work responsibilities and pressure coexist(heavy work responsibilities,occupational risks and stress),demand for high-quality management(expecting the construction of predictive assessment tools and prevention strategies,and pursuing standardized management processes to enhance management effectiveness).CONCLUSION Nursing managers should prioritize the needs and suggestions of nurses in order to enhance their nursing capabilities and provide guidance for standardized management processes.

关键词： Anesthetic nurse Emergence delirium Postoperative complications Cognition Disease management Qualitative research

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Outlier-resistant distributed fusion filtering for nonlinear discrete-time singular systems under a dynamic event-triggered scheme

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 237-249页

作者： Zhibin HU Jun HU cai CHEN Hongjian LIU Xiaojian yi Department of Applied Mathematics Harbin University of Science and TechnologyHarbin150080China Heilongjiang Provincial Key Laboratory of Optimization Control and Intelligent Analysis for Complex Systems Harbin University of Science and TechnologyHarbin150080China School of Automation Harbin University of Science and TechnologyHarbin150080China School of Mathematics and Physics Anhui Polytechnic UniversityWuhu241000China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314003China Tangshan Research Institute Beijing Institute of TechnologyTangshan063099China

This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is used.Moreover,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data transmission.For the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter gains.furthermore,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion rule.As such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation performance.Moreover,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is presented.Finally,the validity of the developed algorithm is checked using a simulation example.

关键词： Distributed fusion filtering Multi-sensor nonlinear singular systems Dynamic event-triggered scheme Outlier-resistant filter Uniform boundedness

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