Objective:To investigate morphological risk factors of basilar aneurysm rupture based on computer tomography angiography(CTA)parameters.Materials and methods:The clinical and CTA data of 43 patients with basilar aneur...Objective:To investigate morphological risk factors of basilar aneurysm rupture based on computer tomography angiography(CTA)parameters.Materials and methods:The clinical and CTA data of 43 patients with basilar aneurysm admitted to Shaanxi Provincial People's Hospital from January 2015 to July 2023 were analyzed.The patients were divided into“ruptured group”and“unruptured group,”and the morphological parameters of aneurysms were measured.The general data and morphological parameters between the two groups were statistically analyzed.Logistic regression was used to analyzed statistically significant parameters,and the receiver operating characteristic curve was drawn to evaluate its diagnostic effectiveness.Results:Irregular aneurysms were more likely to rupture than regular aneurysms(χ^(2)=13.971,P<0.05).The maximum diameter(4.92[3.37-6.94]mm),length-width ratio(1.31[1.14-1.55]),height(4.08[2.71-5.34]mm),aspect ratio(0.99[0.84-1.45]),and inflow angle(133.63±11.21°)of aneurysms in the ruptured group were larger than the unruptured group,and the differences were statistically significant(P<0.05).Binary logistic regression showed that aneurysm shape(OR=39.347,P=0.021),length-width ratio(OR=313.062,P=0.033),and inflow angle(OR=1.156,P=0.004)were independent risk factors for rupture.The area under the curve were 0.809,0.842.and 0.894,respectively.Conclusion:Aneurysm shape,aspect ratio,and blood flow incidence angle are independent risk factors for basilar aneurysm rupture,which means that they can be used to predict the risk of rupture to a certain extent.展开更多
Neoplasms of the vermiform appendix represent 1% of all gastrointestinal tumors, with epithelial and neuroendocrine histological subtypes being the most frequent. When two or more neoplasms with different components o...Neoplasms of the vermiform appendix represent 1% of all gastrointestinal tumors, with epithelial and neuroendocrine histological subtypes being the most frequent. When two or more neoplasms with different components originate synchronically in the appendix with clear margin between them, it is called a collision tumor, with exceptional cases being reported in literature. The purpose is to present two new cases of collision tumors of the appendix and perform a review of the published literature. Two cases of an 82-year-old female and a 41-year-old male with collision tumors of the vermiform appendix are presented, with clinical presentation, radiological evaluation and surgical treatment exposed. Our results are compared with other published reports. In accordance with the other reported cases, both patients presented with low-grade appendiceal mucinous neoplasm (LAMN). Female patient with synchronous goblet cell carcinoma managed with a completion right colectomy and Hyperthermic intraperitoneal chemotherapy (HIPEC) and the other patient with well-differentiated neuroendocrine (NET) tumor managed with laparoscopic appendectomy without adjuvant treatment. Since very few cases have been reported, no diagnostic and therapeutic consensus and guidelines exist up to date. We agree that local, regional, and systemic therapies should be chosen according to the tumor that represents the worst prognosis.展开更多
In this note, the authors prove that the commutator Tb generated by θ-type Calderón-Zygmund operator T and a Lipschitz function b is bounded from Lp(Rn) into Lip(β- np)(Rn) and also maps from L βn (Rn) into BM...In this note, the authors prove that the commutator Tb generated by θ-type Calderón-Zygmund operator T and a Lipschitz function b is bounded from Lp(Rn) into Lip(β- np)(Rn) and also maps from L βn (Rn) into BMO(Rn).展开更多
Purpose:Research dynamics have long been a research interest.It is a macro perspective tool for discovering temporal research trends of a certain discipline or subject.A micro perspective of research dynamics,however,...Purpose:Research dynamics have long been a research interest.It is a macro perspective tool for discovering temporal research trends of a certain discipline or subject.A micro perspective of research dynamics,however,concerning a single researcher or a highly cited paper in terms of their citations and“citations of citations”(forward chaining)remains unexplored.Design/methodology/approach:In this paper,we use a cross-collection topic model to reveal the research dynamics of topic disappearance topic inheritance,and topic innovation in each generation of forward chaining.Findings:For highly cited work,scientific influence exists in indirect citations.Topic modeling can reveal how long this influence exists in forward chaining,as well as its influence.Research limitations:This paper measures scientific influence and indirect scientific influence only if the relevant words or phrases are borrowed or used in direct or indirect citations.Paraphrasing or semantically similar concept may be neglected in this research.Practical implications:This paper demonstrates that a scientific influence exists in indirect citations through its analysis of forward chaining.This can serve as an inspiration on how to adequately evaluate research influence.Originality:The main contributions of this paper are the following three aspects.First,besides research dynamics of topic inheritance and topic innovation,we model topic disappearance by using a cross-collection topic model.Second,we explore the length and character of the research impact through“citations of citations”content analysis.Finally,we analyze the research dynamics of artificial intelligence researcher Geoffrey Hinton’s publications and the topic dynamics of forward chaining.展开更多
Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, th...Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, the patient navigation model has shown its effectiveness in improving the quality of life among patients with chronic diseases and reducing the shortage of current healthcare resources in some area. This study aims to identify the current status and dilemma of the patient navigation model applied in colorectal cancer care in China. Methods: Bibliometric method was used to analyze published articles regarding the application of patient navigation model in colorectal cancer care retrieved from the Web of Science database. Statistics were presented using visualization method processed by the Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software. Results: 124 articles, from 2006 to 2018, covering 14 countries, involving 931 researchers, 356 institutions and 60 publications were obtained;American research papers are the largest components of the aforementioned articles;only one of them is written by Chinese authors. The 3 leading institutions in this domain are University OF Rochester, Ohio State University, Icahn School of Medicine at Mount Sinai, yet the distribution of authors is relatively decentralized. “Cancer” is the main journal that publishes the researches in this domain. Research hotspots are on “cancer prevention and screening”, “health disparities”, “economic evaluation”, “patient navigators”, and “ethnicity”. Conclusion: In China, the research on the patient navigation is still in its infancy. Therefore, the Chinese government should provide more endorsement to this particular area and encourage the cooperation with other countries. China, having a long way to go, should further explore patient navigation on colorectal cancer care and establish a model that matches its cultural backgrounds.展开更多
Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring.Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt se...Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring.Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt season are necessary for climate prediction under global warming.Previous studies on Arctic sea ice phenology did not involve melt ponds that dramatically lower the ice surface albedo and tremendously affect the process of sea ice surface melt.Temporal means and trends of the Arctic sea ice phenology from 1982 to 2017 were examined based on satellite-derived sea ice concentration and albedo measurements.Moreover,the timing of ice ponding and two periods corresponding to it were newly proposed as key stages in the melt season.Therefore,four timings,i.e.,date of snow and ice surface melt onset(MO),date of pond onset(PO),date of sea ice opening(DOO),and date of sea ice retreat(DOR);and three durations,i.e.,melt pond formation period(MPFP,i.e.,MO–PO),melt pond extension period(MPEP,i.e.,PO–DOR),and seasonal loss of ice period(SLIP,i.e.,DOO–DOR),were used.PO ranged from late April in the peripheral seas to late June in the central Arctic Ocean in Bootstrap results,whereas the pan-Arctic was observed nearly 4 days later in NASA Team results.Significant negative trends were presented in the MPEP in the Hudson Bay,the Baffin Bay,the Greenland Sea,the Kara and Barents seas in both results,indicating that the Arctic sea ice undergoes a quick transition from ice to open water,thereby extending the melt season year to year.The high correlation coefficient between MO and PO,MPFP illustrated that MO predominates the process of pond formation.展开更多
In this note, the author prove that maximal Bocher-Riesz commutator Bbδ , generated by operator Bδ , and function b ∈ BMO(ω) is a bounded operator from Lp(μ) into Lp (ν), where ω∈ (μν-1 )1 p , μ , ν∈ Ap f...In this note, the author prove that maximal Bocher-Riesz commutator Bbδ , generated by operator Bδ , and function b ∈ BMO(ω) is a bounded operator from Lp(μ) into Lp (ν), where ω∈ (μν-1 )1 p , μ , ν∈ Ap for 1 < p < ∞. The proof relies heavily on the pointwise estimates for the sharp maximal function of the commutator Bbδ, .展开更多
In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseas...In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseases are reviewed from the aspects of agricultural control,botanical pesticide control and microbial pesticide control,and the development prospects are proposed,including accelerating innovative research on botani-cal pesticide control such as Chinese herb extracts,and screening microbial pesticides from valuable bio-control bacteria or plant endophyte metabolites for commercial production and utilization.展开更多
The aim of this article is to review our recent work on nonlocal dynamics of non-Gaussian systems arising in a gene regulatory network.We have used the mean exit time,escape probability and maximal likely trajectory t...The aim of this article is to review our recent work on nonlocal dynamics of non-Gaussian systems arising in a gene regulatory network.We have used the mean exit time,escape probability and maximal likely trajectory to quantify dynamical behaviors of a stochastic diferential system with non-Gaussianα-stable Lévy motions,to examine how the nonGaussianity index and noise intensity afect the gene transcription processes.展开更多
Seasonal distribution of mono-modal, monsoonal rainfall across the semi-arid ecotone of sub-Saharan of West Africa is highly variable and unpredictable. The ever-present risk of drought and crop failure in this enviro...Seasonal distribution of mono-modal, monsoonal rainfall across the semi-arid ecotone of sub-Saharan of West Africa is highly variable and unpredictable. The ever-present risk of drought and crop failure in this environment often results in food shortages that are met by emergency food aid. Humanitarian assistance planners would be better prepared for such interventions in a timely manner if they have reliable indicators that forewarn the impending failure of the rains. A good indicator would be a characteristic of the seasonal rainfall distribution that can be shown to be reasonably invariant over time and space. The objective of this study is to investigate whether such invariance existed for the seasonal median date (meaning the date when 50% of the seasonal total occurs). Such invariance is expected since the sun’s cyclic declination forces the advance and retreat of the Inter-tropical Front over West Africa. We examined the statistical properties of the seasonal median date for 1349 station-years of rainfall records for 30 rainfall stations in Burkina Faso and Niger with coordinates ranging from 9.88° to 18.5° north latitude and -4.77° to 13.2° longitude. The results showed that the median date was quite narrowly distributed over years with rather weak dependence on geographical coordinates. It can therefore be used as a reasonable ex-ante indicator of the success or failure of the rains as the rainy season progress.展开更多
This study was designed to explore the prevalence of fibrovascular proliferation not regressed in zone Ⅱ stage 3 retinopathy of prematurity(ROP)after initial intravitreal ranibizumab(IVR)injections and to explore the...This study was designed to explore the prevalence of fibrovascular proliferation not regressed in zone Ⅱ stage 3 retinopathy of prematurity(ROP)after initial intravitreal ranibizumab(IVR)injections and to explore the possible influence factors.Fifty-seven patients(108 eyes)with ROP who underwent intravitreal injection of ranibizumab between January 2013 and July 2014 participated in the retrospective study.Based on regress of fibrovascular tissue or not after initial injections of ranibizumab,eligible eyes were divided into two groups.Data was collected and analyzed with SPSS 16.0.In the study,108 eyes of 57 patients(18 females,39 males)underwent initial intravitreal injection.The mean birth weight was 1,440.0±357.7 g and the mean gestational age was 30.5±2.0 weeks.Eight of 57(14.0%)patients showed unfavorable fibrovascular proliferation after initial ranibizumab treatment within 2 weeks.Among them,11 eyes were controlled by further laser treatment and 3 eyes underwent vitrectomy.The difference of occurrence rate in hemorrhage between the two groups was significant(P<0.030),and the unfavorable group required more laser treatment(P<0.001).The incidence of unfavorable fibrovascular proliferation was relatively high,and intraocular hemorrhage was possibly associated with the progress in zone Ⅱ stage 3 ROP after initial IVR injection.展开更多
With the rapid development of the society,water contamination events cause great loss if the accidents happen in the water supply system.A large number of sensor nodes of water quality are deployed in the water supply...With the rapid development of the society,water contamination events cause great loss if the accidents happen in the water supply system.A large number of sensor nodes of water quality are deployed in the water supply network to detect and warn the contamination events to prevent pollution from speading.If all of sensor nodes detect and transmit the water quality data when the contamination occurs,it results in the heavy communication overhead.To reduce the communication overhead,the Connected Dominated Set construction algorithm-Rule K,is adopted to select a part fo sensor nodes.Moreover,in order to improve the detection accuracy,a Spatial-Temporal Abnormal Event Detection Algorithm with Multivariate water quality data(M-STAEDA)was proposed.In M-STAEDA,first,Back Propagation neural network models are adopted to analyze the multiple water quality parameters and calculate the possible outliers.Then,M-STAEDA algorithm determines the potential contamination events through Bayesian sequential analysis to estimate the probability of a contamination event.Third,it can make decision based on the multiple event probabilities fusion.Finally,a spatial correlation model is applied to determine the spatial-temporal contamination event in the water supply networks.The experimental results indicate that the proposed M-STAEDA algorithm can obtain more accuracy with BP neural network model and improve the rate of detection and the false alarm rate,compared with the temporal event detection of Single Variate Temporal Abnormal Event Detection Algorithm(M-STAEDA).展开更多
Purpose: By case studies of the service for regional economic development(SRED) carried out by the National Science Library of the Chinese Academy of Sciences(NSLC), this article tries to describe basic directions of ...Purpose: By case studies of the service for regional economic development(SRED) carried out by the National Science Library of the Chinese Academy of Sciences(NSLC), this article tries to describe basic directions of special libraries in the SRED.Design/methodology/approach: By comparing the aims and service forms of the SRED provided by domestic and foreign libraries and information service institutions, the authors examined the basic services provided by special libraries. Through a summary of the SRED exploration carried out by the NSLC, the authors introduce its main content, service methods, products, and service mechanisms. By analyzing the information needs of SRED users and summarizing users' practical experiences of services, the authors propose a design for the SRED framework of the NSLC. In addition, the authors mention key points to be noticed during the process of service implementation, illustrating them with a number of selected SRED cases. The authors suggest that the SRED network and joint service mechanism are effective ways to implement SRED services. Findings: Based on information resource and expert networks, special libraries like the NSLC can carry out SRED to meet user requirements. The NSLC has not only constructed its own SRED framework, but has also expanded the patron service to the industrial intelligence service area. By setting up a nationwide S&T(science and technology) novelty search network and a literature and information service alliance, the NSLC provides a variety of information training services. This enriches the content of the knowledge service of special libraries and enlarges the library service of the NSLC.Research limitations: The SRED of Chinese libraries is still in the exploratory stage. Questions as how to scientifically design service content and service modes, and how to establish a sustainable regional service system based on user needs are still being researchedand discussed. Furthermore, we need to pay more attention to the construction of the service network and respond more quickly to feedback while creating the SRED.Practical implications: The SRED experience of the NSLC has shown that special libraries can implement a knowledge service for economic development, and the SRED is an important direction of knowledge services for special libraries.Originality/value: Through describing a practical SRED, this paper provides a valuable reference for libraries in the transformation process from library service to knowledge service. The experimental SRED of the NSLC has verified the rationality of our service framework in support of regional economic development.展开更多
A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophtha...A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection concentrations.The sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime analyses.The activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade TCT.Both 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,respectively.The photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap experiments.The Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.展开更多
Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and ...Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and their underlying mechanism remains largely unknown. Here, we report a rice floury endosperm22(flo22) mutant with delayed amyloplast development in endosperm cells. Map-based cloning and complementation tests demonstrated that FLO22 encodes a mitochondrion-localized P-type PPR protein.Mutation of FLO22 resulting in defective transsplicing of mitochondrial nad1 intron 1 and perhaps causing instability of mature transcripts affected assembly and activity of complex Ⅰ, and mitochondrial morphology and function. RNA-seq analysis showed that expression levels of many genes involved in starch and sucrose metabolism were significantly down-regulated in the flo22mutant compared with the wild type, whereas genes related to oxidative phosphorylation and the tricarboxylic acid cycle were significantly upregulated. In addition to involvement in splicing as a P-type PPR protein, we found that FLO22 interacted with DYW3, a DYW-type PPR protein, and they may function synergistically in mitochondrial RNA editing. The present work indicated that FLO22 plays an important role in endosperm development and plant growth by participating in nad1 maturation and multi-site editing of mitochondrial messager RNA.展开更多
Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidanc...Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidance.Herein,we demonstrate a facile strategy to introduce two types of defects into the CuO-ZnO model catalyst,namely oxygen vacancies(OVs)induced by H2 partial reduction and localized amorphous regions(LARs)generated via the ball milling process.Using industrially important Rochow–Müller reaction as a representative,we found OVs predominantly improved the target product selectivity of dimethyldichlorosilane,while LARs significantly increased the conversion of reactant Si.The CuO-ZnO catalyst with optimized OVs and LARs contents achieved the best catalytic property.Theoretical calculation further revealed that LARs promote the generation of the Cu3Si active phase,and OVs impact the electronic structure of the Cu3Si active phase.This work provides a new understanding of the roles of different catalyst defects and a feasible way of engineering the catalyst structure for better catalytic performances.展开更多
Plastid-to-nucleus retrograde signaling coordinates nuclear gene expression with chloroplast developmental status and is essential for the photoautotrophic lifestyle of plants.Previous studies have established that te...Plastid-to-nucleus retrograde signaling coordinates nuclear gene expression with chloroplast developmental status and is essential for the photoautotrophic lifestyle of plants.Previous studies have established that tetrapyrrole biosynthesis(TPB)and plastid gene expression(PGE)play essential roles in plastid retrograde signaling during early chloroplast biogenesis;however,their functional relationship remains unknown.In this study,we generated a series of rice TPB-related gun(genome uncoupled)mutants and systematically analyzed their effects on nuclear and plastid gene expression under normal conditions or when subjected to treatments with norflurazon(NF;a noncompetitive inhibitor of carotenoid biosynthesis)and/or lincomycin(Lin;a specific inhibitor of plastid translation).We show that under NF treatment,expression of plastid-encoded polymerase(PEP)-transcribed genes is significantly reduced in the wild type but is derepressed in the TPB-related gun mutants.We further demonstrate that the derepressed expression of PEPtranscribed genes may be caused by increased expression of the PEP core subunit and nuclear-encoded sigma factors and by elevated copy numbers of plastid genome per haploid genome.In addition,we show that expression of photosynthesis-associated nuclear genes(PhANGs)and PEP-transcribed genes is correlated in the rice TPB-related gun mutants,with or without NF or Lin treatment.A similar correlation between PhANGs and PGE is also observed in the Arabidopsis gun4 and gun5 mutants.Moreover,we show that increased expression of PEP-transcribed plastid genes is necessary for the gun phenotype in NF-treated TPB-related gun mutants.Further,we provide evidence that these TPB-related GUN genes act upstream of GUN1 in the regulation of retrograde signaling.Taken together,our results suggest that the TPB-related GUN genes control retrograde plastid signaling by regulating the PGE-dependent retrograde signaling pathway.展开更多
文摘Objective:To investigate morphological risk factors of basilar aneurysm rupture based on computer tomography angiography(CTA)parameters.Materials and methods:The clinical and CTA data of 43 patients with basilar aneurysm admitted to Shaanxi Provincial People's Hospital from January 2015 to July 2023 were analyzed.The patients were divided into“ruptured group”and“unruptured group,”and the morphological parameters of aneurysms were measured.The general data and morphological parameters between the two groups were statistically analyzed.Logistic regression was used to analyzed statistically significant parameters,and the receiver operating characteristic curve was drawn to evaluate its diagnostic effectiveness.Results:Irregular aneurysms were more likely to rupture than regular aneurysms(χ^(2)=13.971,P<0.05).The maximum diameter(4.92[3.37-6.94]mm),length-width ratio(1.31[1.14-1.55]),height(4.08[2.71-5.34]mm),aspect ratio(0.99[0.84-1.45]),and inflow angle(133.63±11.21°)of aneurysms in the ruptured group were larger than the unruptured group,and the differences were statistically significant(P<0.05).Binary logistic regression showed that aneurysm shape(OR=39.347,P=0.021),length-width ratio(OR=313.062,P=0.033),and inflow angle(OR=1.156,P=0.004)were independent risk factors for rupture.The area under the curve were 0.809,0.842.and 0.894,respectively.Conclusion:Aneurysm shape,aspect ratio,and blood flow incidence angle are independent risk factors for basilar aneurysm rupture,which means that they can be used to predict the risk of rupture to a certain extent.
文摘Neoplasms of the vermiform appendix represent 1% of all gastrointestinal tumors, with epithelial and neuroendocrine histological subtypes being the most frequent. When two or more neoplasms with different components originate synchronically in the appendix with clear margin between them, it is called a collision tumor, with exceptional cases being reported in literature. The purpose is to present two new cases of collision tumors of the appendix and perform a review of the published literature. Two cases of an 82-year-old female and a 41-year-old male with collision tumors of the vermiform appendix are presented, with clinical presentation, radiological evaluation and surgical treatment exposed. Our results are compared with other published reports. In accordance with the other reported cases, both patients presented with low-grade appendiceal mucinous neoplasm (LAMN). Female patient with synchronous goblet cell carcinoma managed with a completion right colectomy and Hyperthermic intraperitoneal chemotherapy (HIPEC) and the other patient with well-differentiated neuroendocrine (NET) tumor managed with laparoscopic appendectomy without adjuvant treatment. Since very few cases have been reported, no diagnostic and therapeutic consensus and guidelines exist up to date. We agree that local, regional, and systemic therapies should be chosen according to the tumor that represents the worst prognosis.
基金Supported by NSFC(10571014)NSFC(10571156)+1 种基金the Doctor Foundation of Jxnu (2443)the Natural Science Foundation of Jiangxi province(2008GZS0051)
文摘In this note, the authors prove that the commutator Tb generated by θ-type Calderón-Zygmund operator T and a Lipschitz function b is bounded from Lp(Rn) into Lip(β- np)(Rn) and also maps from L βn (Rn) into BMO(Rn).
基金This work is supported by the Programs for the Young Talents of National Science Library,Chinese Academy of Sciences(Grant No.2019QNGR003).
文摘Purpose:Research dynamics have long been a research interest.It is a macro perspective tool for discovering temporal research trends of a certain discipline or subject.A micro perspective of research dynamics,however,concerning a single researcher or a highly cited paper in terms of their citations and“citations of citations”(forward chaining)remains unexplored.Design/methodology/approach:In this paper,we use a cross-collection topic model to reveal the research dynamics of topic disappearance topic inheritance,and topic innovation in each generation of forward chaining.Findings:For highly cited work,scientific influence exists in indirect citations.Topic modeling can reveal how long this influence exists in forward chaining,as well as its influence.Research limitations:This paper measures scientific influence and indirect scientific influence only if the relevant words or phrases are borrowed or used in direct or indirect citations.Paraphrasing or semantically similar concept may be neglected in this research.Practical implications:This paper demonstrates that a scientific influence exists in indirect citations through its analysis of forward chaining.This can serve as an inspiration on how to adequately evaluate research influence.Originality:The main contributions of this paper are the following three aspects.First,besides research dynamics of topic inheritance and topic innovation,we model topic disappearance by using a cross-collection topic model.Second,we explore the length and character of the research impact through“citations of citations”content analysis.Finally,we analyze the research dynamics of artificial intelligence researcher Geoffrey Hinton’s publications and the topic dynamics of forward chaining.
文摘Background: The mortality rate of colorectal cancer in China is on the rise, which has exceeded the global average rate, thus making the care of colorectal cancer widely concerned. As a comprehensive nursing model, the patient navigation model has shown its effectiveness in improving the quality of life among patients with chronic diseases and reducing the shortage of current healthcare resources in some area. This study aims to identify the current status and dilemma of the patient navigation model applied in colorectal cancer care in China. Methods: Bibliometric method was used to analyze published articles regarding the application of patient navigation model in colorectal cancer care retrieved from the Web of Science database. Statistics were presented using visualization method processed by the Bibliographic Items Co-occurrence Matrix Builder (BICOMB) software. Results: 124 articles, from 2006 to 2018, covering 14 countries, involving 931 researchers, 356 institutions and 60 publications were obtained;American research papers are the largest components of the aforementioned articles;only one of them is written by Chinese authors. The 3 leading institutions in this domain are University OF Rochester, Ohio State University, Icahn School of Medicine at Mount Sinai, yet the distribution of authors is relatively decentralized. “Cancer” is the main journal that publishes the researches in this domain. Research hotspots are on “cancer prevention and screening”, “health disparities”, “economic evaluation”, “patient navigators”, and “ethnicity”. Conclusion: In China, the research on the patient navigation is still in its infancy. Therefore, the Chinese government should provide more endorsement to this particular area and encourage the cooperation with other countries. China, having a long way to go, should further explore patient navigation on colorectal cancer care and establish a model that matches its cultural backgrounds.
基金The National Key Research and Development Program of China under contract No.2018YFC1406102the Funds for the Distinguished Young Scientists of Hubei Province(China)under contract No.2019CFA057the National Natural Science Foundation of China under contract Nos 41941010 and 41776200。
文摘Information on the Arctic sea ice climate indicators is crucial to business strategic planning and climate monitoring.Data on the evolvement of the Arctic sea ice and decadal trends of phenology factors during melt season are necessary for climate prediction under global warming.Previous studies on Arctic sea ice phenology did not involve melt ponds that dramatically lower the ice surface albedo and tremendously affect the process of sea ice surface melt.Temporal means and trends of the Arctic sea ice phenology from 1982 to 2017 were examined based on satellite-derived sea ice concentration and albedo measurements.Moreover,the timing of ice ponding and two periods corresponding to it were newly proposed as key stages in the melt season.Therefore,four timings,i.e.,date of snow and ice surface melt onset(MO),date of pond onset(PO),date of sea ice opening(DOO),and date of sea ice retreat(DOR);and three durations,i.e.,melt pond formation period(MPFP,i.e.,MO–PO),melt pond extension period(MPEP,i.e.,PO–DOR),and seasonal loss of ice period(SLIP,i.e.,DOO–DOR),were used.PO ranged from late April in the peripheral seas to late June in the central Arctic Ocean in Bootstrap results,whereas the pan-Arctic was observed nearly 4 days later in NASA Team results.Significant negative trends were presented in the MPEP in the Hudson Bay,the Baffin Bay,the Greenland Sea,the Kara and Barents seas in both results,indicating that the Arctic sea ice undergoes a quick transition from ice to open water,thereby extending the melt season year to year.The high correlation coefficient between MO and PO,MPFP illustrated that MO predominates the process of pond formation.
基金supported by the NNSF (10961015, 11261023) of Chinathe Jiangxi Natural Science Foundation of China (20122BAB201011), GJJ12203
文摘In this note, the author prove that maximal Bocher-Riesz commutator Bbδ , generated by operator Bδ , and function b ∈ BMO(ω) is a bounded operator from Lp(μ) into Lp (ν), where ω∈ (μν-1 )1 p , μ , ν∈ Ap for 1 < p < ∞. The proof relies heavily on the pointwise estimates for the sharp maximal function of the commutator Bbδ, .
基金Supported by Open Fund Project of Key Laboratory of Plant Nutrition and Fertilizer,Ministry of Agriculture and Rural Affairs"Study on Precise Nutrient Demand Model of Corn"(KLPNF-2018-4)
文摘In order to provide the technological support for further implementing measures of reducing chemical pesticide to control plant diseases,the research progress on non-chemical pesticide measures to control plant diseases are reviewed from the aspects of agricultural control,botanical pesticide control and microbial pesticide control,and the development prospects are proposed,including accelerating innovative research on botani-cal pesticide control such as Chinese herb extracts,and screening microbial pesticides from valuable bio-control bacteria or plant endophyte metabolites for commercial production and utilization.
基金This work was supported by the National Natural Science Foundation of China Grants 11801192,11531006,11371367,11271290 and 11771062.
文摘The aim of this article is to review our recent work on nonlocal dynamics of non-Gaussian systems arising in a gene regulatory network.We have used the mean exit time,escape probability and maximal likely trajectory to quantify dynamical behaviors of a stochastic diferential system with non-Gaussianα-stable Lévy motions,to examine how the nonGaussianity index and noise intensity afect the gene transcription processes.
文摘Seasonal distribution of mono-modal, monsoonal rainfall across the semi-arid ecotone of sub-Saharan of West Africa is highly variable and unpredictable. The ever-present risk of drought and crop failure in this environment often results in food shortages that are met by emergency food aid. Humanitarian assistance planners would be better prepared for such interventions in a timely manner if they have reliable indicators that forewarn the impending failure of the rains. A good indicator would be a characteristic of the seasonal rainfall distribution that can be shown to be reasonably invariant over time and space. The objective of this study is to investigate whether such invariance existed for the seasonal median date (meaning the date when 50% of the seasonal total occurs). Such invariance is expected since the sun’s cyclic declination forces the advance and retreat of the Inter-tropical Front over West Africa. We examined the statistical properties of the seasonal median date for 1349 station-years of rainfall records for 30 rainfall stations in Burkina Faso and Niger with coordinates ranging from 9.88° to 18.5° north latitude and -4.77° to 13.2° longitude. The results showed that the median date was quite narrowly distributed over years with rather weak dependence on geographical coordinates. It can therefore be used as a reasonable ex-ante indicator of the success or failure of the rains as the rainy season progress.
基金This work was supported by the National Natural Science Foundation of China(grant No.81470649).
文摘This study was designed to explore the prevalence of fibrovascular proliferation not regressed in zone Ⅱ stage 3 retinopathy of prematurity(ROP)after initial intravitreal ranibizumab(IVR)injections and to explore the possible influence factors.Fifty-seven patients(108 eyes)with ROP who underwent intravitreal injection of ranibizumab between January 2013 and July 2014 participated in the retrospective study.Based on regress of fibrovascular tissue or not after initial injections of ranibizumab,eligible eyes were divided into two groups.Data was collected and analyzed with SPSS 16.0.In the study,108 eyes of 57 patients(18 females,39 males)underwent initial intravitreal injection.The mean birth weight was 1,440.0±357.7 g and the mean gestational age was 30.5±2.0 weeks.Eight of 57(14.0%)patients showed unfavorable fibrovascular proliferation after initial ranibizumab treatment within 2 weeks.Among them,11 eyes were controlled by further laser treatment and 3 eyes underwent vitrectomy.The difference of occurrence rate in hemorrhage between the two groups was significant(P<0.030),and the unfavorable group required more laser treatment(P<0.001).The incidence of unfavorable fibrovascular proliferation was relatively high,and intraocular hemorrhage was possibly associated with the progress in zone Ⅱ stage 3 ROP after initial IVR injection.
文摘With the rapid development of the society,water contamination events cause great loss if the accidents happen in the water supply system.A large number of sensor nodes of water quality are deployed in the water supply network to detect and warn the contamination events to prevent pollution from speading.If all of sensor nodes detect and transmit the water quality data when the contamination occurs,it results in the heavy communication overhead.To reduce the communication overhead,the Connected Dominated Set construction algorithm-Rule K,is adopted to select a part fo sensor nodes.Moreover,in order to improve the detection accuracy,a Spatial-Temporal Abnormal Event Detection Algorithm with Multivariate water quality data(M-STAEDA)was proposed.In M-STAEDA,first,Back Propagation neural network models are adopted to analyze the multiple water quality parameters and calculate the possible outliers.Then,M-STAEDA algorithm determines the potential contamination events through Bayesian sequential analysis to estimate the probability of a contamination event.Third,it can make decision based on the multiple event probabilities fusion.Finally,a spatial correlation model is applied to determine the spatial-temporal contamination event in the water supply networks.The experimental results indicate that the proposed M-STAEDA algorithm can obtain more accuracy with BP neural network model and improve the rate of detection and the false alarm rate,compared with the temporal event detection of Single Variate Temporal Abnormal Event Detection Algorithm(M-STAEDA).
基金supported by the National Science Library of the Chinese Acedemy of Sciencesthe Bureau of Development and Planning of the Chinese Academy of Sciences
文摘Purpose: By case studies of the service for regional economic development(SRED) carried out by the National Science Library of the Chinese Academy of Sciences(NSLC), this article tries to describe basic directions of special libraries in the SRED.Design/methodology/approach: By comparing the aims and service forms of the SRED provided by domestic and foreign libraries and information service institutions, the authors examined the basic services provided by special libraries. Through a summary of the SRED exploration carried out by the NSLC, the authors introduce its main content, service methods, products, and service mechanisms. By analyzing the information needs of SRED users and summarizing users' practical experiences of services, the authors propose a design for the SRED framework of the NSLC. In addition, the authors mention key points to be noticed during the process of service implementation, illustrating them with a number of selected SRED cases. The authors suggest that the SRED network and joint service mechanism are effective ways to implement SRED services. Findings: Based on information resource and expert networks, special libraries like the NSLC can carry out SRED to meet user requirements. The NSLC has not only constructed its own SRED framework, but has also expanded the patron service to the industrial intelligence service area. By setting up a nationwide S&T(science and technology) novelty search network and a literature and information service alliance, the NSLC provides a variety of information training services. This enriches the content of the knowledge service of special libraries and enlarges the library service of the NSLC.Research limitations: The SRED of Chinese libraries is still in the exploratory stage. Questions as how to scientifically design service content and service modes, and how to establish a sustainable regional service system based on user needs are still being researchedand discussed. Furthermore, we need to pay more attention to the construction of the service network and respond more quickly to feedback while creating the SRED.Practical implications: The SRED experience of the NSLC has shown that special libraries can implement a knowledge service for economic development, and the SRED is an important direction of knowledge services for special libraries.Originality/value: Through describing a practical SRED, this paper provides a valuable reference for libraries in the transformation process from library service to knowledge service. The experimental SRED of the NSLC has verified the rationality of our service framework in support of regional economic development.
基金Project supported by the National Natural Science Foundation of China(22063010)the Youth Innovation Team of Shaanxi Universities。
文摘A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection concentrations.The sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime analyses.The activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade TCT.Both 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,respectively.The photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap experiments.The Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.
基金supported by grants from the National Key R&D Program of China (2021YFF1000200)National Natural Science Foundation of China (31901513)+6 种基金the “JBGS” Project of Seed Industry Revitalization in Jiangsu Province (JBGS [2021]008)Jiangsu Province Agriculture Independent Innovation Fund Project (CX(19)1002)the Fundamental Research Funds for the Central Universities (KJQN202005)the China Postdoctoral Science Foundation (2019M661864)also supported by the Key Laboratory of Biology, Genetics, and Breeding of Japonica Rice in Mid-lower Yangtze River, Ministry of Agriculture, Chinathe Jiangsu Collaborative Innovation Center for Modern Crop ProductionNational Observation and Research Station of Rice Germplasm Resources, Nanjing, Jiangsu。
文摘Most of the reported P-type pentatricopeptide repeat(PPR) proteins play roles in organelle RNA stabilization and splicing. However, P-type PPRs involved in both RNA splicing and editing have rarely been reported, and their underlying mechanism remains largely unknown. Here, we report a rice floury endosperm22(flo22) mutant with delayed amyloplast development in endosperm cells. Map-based cloning and complementation tests demonstrated that FLO22 encodes a mitochondrion-localized P-type PPR protein.Mutation of FLO22 resulting in defective transsplicing of mitochondrial nad1 intron 1 and perhaps causing instability of mature transcripts affected assembly and activity of complex Ⅰ, and mitochondrial morphology and function. RNA-seq analysis showed that expression levels of many genes involved in starch and sucrose metabolism were significantly down-regulated in the flo22mutant compared with the wild type, whereas genes related to oxidative phosphorylation and the tricarboxylic acid cycle were significantly upregulated. In addition to involvement in splicing as a P-type PPR protein, we found that FLO22 interacted with DYW3, a DYW-type PPR protein, and they may function synergistically in mitochondrial RNA editing. The present work indicated that FLO22 plays an important role in endosperm development and plant growth by participating in nad1 maturation and multi-site editing of mitochondrial messager RNA.
基金support from the National Natural Science Foundation of China(Nos.21878301 and 21978299)the Open Research Fund of State Key Laboratory of Multiphase Complex Systems(No.MPCS-2021-D-08)+4 种基金GRINM Group.Y.J.J.thanks the financial support from the Research Foundation for Advanced Talents of Beijing Technology and Business University(No.19008020159)X.L.C.thanks the financial support from the project for improving the research ability of postgraduate from Beijing Technology and Business University(No.19008022056)L.W.X.thanks the financial support from the Research Foundation for Youth Scholars of Beijing Technology and Business University(No.QNJJ2022-22)Z.Y.Z.thanks the financial support of Guangdong Provincial Key Laboratory of Materials and Technologies for Energy Conversion(MATEC)Guangdong Technion-Israel Institute of Technology and Guangdong Key Discipline Fund(2022)for this collaboration。
文摘Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidance.Herein,we demonstrate a facile strategy to introduce two types of defects into the CuO-ZnO model catalyst,namely oxygen vacancies(OVs)induced by H2 partial reduction and localized amorphous regions(LARs)generated via the ball milling process.Using industrially important Rochow–Müller reaction as a representative,we found OVs predominantly improved the target product selectivity of dimethyldichlorosilane,while LARs significantly increased the conversion of reactant Si.The CuO-ZnO catalyst with optimized OVs and LARs contents achieved the best catalytic property.Theoretical calculation further revealed that LARs promote the generation of the Cu3Si active phase,and OVs impact the electronic structure of the Cu3Si active phase.This work provides a new understanding of the roles of different catalyst defects and a feasible way of engineering the catalyst structure for better catalytic performances.
基金supported by grants from the National Natural Science Foundation of China(91935301)National Natural Science Foundation of China Joint Program(U1701232)+4 种基金Jiangsu Science and Technology Development Program(BE2021360)Jiangsu Agricultural Science and Technology Innovation Fund Project(SCX(19)1079)Jiangsu Province Agriculture Independent Innovation Fund Project(CX(19)1002)National Key Research and Development Program of China(2016YFD0100903)the Fundamental Research Funds for the Central Universities(JCQY201902).
文摘Plastid-to-nucleus retrograde signaling coordinates nuclear gene expression with chloroplast developmental status and is essential for the photoautotrophic lifestyle of plants.Previous studies have established that tetrapyrrole biosynthesis(TPB)and plastid gene expression(PGE)play essential roles in plastid retrograde signaling during early chloroplast biogenesis;however,their functional relationship remains unknown.In this study,we generated a series of rice TPB-related gun(genome uncoupled)mutants and systematically analyzed their effects on nuclear and plastid gene expression under normal conditions or when subjected to treatments with norflurazon(NF;a noncompetitive inhibitor of carotenoid biosynthesis)and/or lincomycin(Lin;a specific inhibitor of plastid translation).We show that under NF treatment,expression of plastid-encoded polymerase(PEP)-transcribed genes is significantly reduced in the wild type but is derepressed in the TPB-related gun mutants.We further demonstrate that the derepressed expression of PEPtranscribed genes may be caused by increased expression of the PEP core subunit and nuclear-encoded sigma factors and by elevated copy numbers of plastid genome per haploid genome.In addition,we show that expression of photosynthesis-associated nuclear genes(PhANGs)and PEP-transcribed genes is correlated in the rice TPB-related gun mutants,with or without NF or Lin treatment.A similar correlation between PhANGs and PGE is also observed in the Arabidopsis gun4 and gun5 mutants.Moreover,we show that increased expression of PEP-transcribed plastid genes is necessary for the gun phenotype in NF-treated TPB-related gun mutants.Further,we provide evidence that these TPB-related GUN genes act upstream of GUN1 in the regulation of retrograde signaling.Taken together,our results suggest that the TPB-related GUN genes control retrograde plastid signaling by regulating the PGE-dependent retrograde signaling pathway.
