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Interplay between mesenchymal stromal cells and the immune system after transplantation: implications for advanced cell therapy in the retina
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作者 María Norte-Muñoz David García-Bernal +2 位作者 Diego García-Ayuso Manuel Vidal-Sanz Marta Agudo-Barriuso 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期542-547,共6页
Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the und... Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical models.Mesenchymal stromal cells are well positioned as therapeutics because they address the underlying mechanisms of neurodegeneration,namely trophic factor deprivation and neuroinflammation.Most studies have focused on the beneficial effects of mesenchymal stromal cell transplantation on neuronal survival or functional improvement.However,little attention has been paid to the interaction between mesenchymal stromal cells and the host immune system due to the immunomodulatory properties of mesenchymal stromal cells and the long-held belief of the immunoprivileged status of the central nervous system.Here,we review the crosstalk between mesenchymal stromal cells and the immune system in general and in the context of the central nervous system,focusing on recent work in the retina and the importance of the type of transplantation. 展开更多
关键词 adaptive immunity cell therapy central nervous system immune system innate immunity mesenchymal stromal cells NEUROREGENERATION preclinical studies RETINA TRANSPLANTATION
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The Representation of Soil Moisture−Atmosphere Feedbacks across the Tibetan Plateau in CMIP6 被引量:1
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作者 Joshua TALIB Omar V.MÜLLER +2 位作者 Emma J.BARTON Christopher M.TAYLOR Pier Luigi VIDALE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第11期2063-2081,共19页
Thermal processes on the Tibetan Plateau(TP)influence atmospheric conditions on regional and global scales.Given this,previous work has shown that soil moisture−driven surface flux variations feed back onto the atmosp... Thermal processes on the Tibetan Plateau(TP)influence atmospheric conditions on regional and global scales.Given this,previous work has shown that soil moisture−driven surface flux variations feed back onto the atmosphere.Whilst soil moisture is a source of atmospheric predictability,no study has evaluated soil moisture−atmosphere coupling on the TP in general circulation models(GCMs).In this study,we use several analysis techniques to assess soil moisture−atmosphere coupling in CMIP6 simulations including:instantaneous coupling indices;analysis of flux and atmospheric behaviour during dry spells;and a quantification of the preference for convection over drier soils.Through these metrics we partition feedbacks into their atmospheric and terrestrial components.Consistent with previous global studies,we conclude substantial inter-model differences in the representation of soil moisture−atmosphere coupling,and that most models underestimate such feedbacks.Focusing on dry spell analysis,most models underestimate increased sensible heat during periods of rainfall deficiency.For example,the model-mean bias in anomalous sensible heat flux is 10 W m−2(≈25%)smaller compared to observations.Deficient dry-spell sensible heat fluxes lead to a weaker atmospheric response.We also find that most GCMs fail to capture the negative feedback between soil moisture and deep convection.The poor simulation of feedbacks in CMIP6 experiments suggests that forecast models also struggle to exploit soil moisture−driven predictability.To improve the representation of land−atmosphere feedbacks requires developments in not only atmospheric modelling,but also surface processes,as we find weak relationships between rainfall biases and coupling indexes. 展开更多
关键词 model evaluation land-atmosphere feedbacks Tibetan Plateau PRECIPITATION surface energy balance
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Application of the extended Fourier amplitude sensitivity testing(FAST)method to inflated,axial stretched,and residually stressed cylinders
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作者 H.ASGHARI H.TOPOL +1 位作者 B.MARKERT J.MERODIO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2139-2162,共24页
This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafuncti... This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual stresses.The metafunctions and the Ishigami function are considered in the sensitivity analysis(SA).The effects of the input variables on the output variables are investigated,and the most important parameters of the system under the applied pressure and axial force such as the axial stretch and the azimuthal stretch are determined. 展开更多
关键词 sensitivity analysis(SA) Fourier amplitude sensitivity test(FAST)method cylindrical inflation nonlinear elasticity
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Feeding ecology of a highly aerial bird during its long breeding season
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作者 Sandra Fernandes Vanessa A.Mata Luis P.da Silva 《Avian Research》 SCIE CSCD 2023年第1期62-69,共8页
Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aer... Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aerial birds has been mostly studied through techniques that fail to produce highly resolved prey identifications,and for that have been replaced by molecular techniques,such as DNA metabarcoding.Faecal samples of Pallid Swifts were monthly collected from a colony in the north of Portugal during the breeding season.DNA from the faecal samples was used to sex the birds and to identify the arthropods present in the diet through DNA metabarcoding.From the detected prey items,74 families were identified belonging to 16 orders,with Hymenoptera and Hemiptera being the most frequently consumed.There were seasonal variations in diet richness,composition and prey size.Regarding the diet of males and females,although no differences were found between the diet of males and females in terms of composition and richness,there were differences in the size of arthropods preyed by the different sexes,with males feeding on larger arthropods.The large seasonal variation in Pallid Swifts’diet during the breeding season is probably a result of spatiotemporal variation in aerial prey,of which swifts likely predate opportunistically.Although no significant differences were detected in diet richness and composition between sexes,the fact that males consumed larger prey may suggest the existence of sexual dietary segregation in this group of birds.At last,several pest species were found in these swifts’diet,which,if studied through DNA metabarcoding,can be used to monitor small arthropods,including airborne pests. 展开更多
关键词 AMerial foraging Apus plius Dietary s-ssonal variation FReeding omlogy Metahercoding Opimel foraging theoary
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Appraisal of Engineering Phases of a Mineral Asset: From Exploration to Mine Approval
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作者 Edmundo Tulcanaza 《Journal of Minerals and Materials Characterization and Engineering》 CAS 2023年第3期69-79,共11页
It is well known that the most common methodology for evaluating a mineral asset is the NPV. Most of the mining companies employ this technique for evaluating the expected economic benefits provided by the exploration... It is well known that the most common methodology for evaluating a mineral asset is the NPV. Most of the mining companies employ this technique for evaluating the expected economic benefits provided by the exploration and exploitation of a mineral deposit. However, companies also wish to know how their assets are creating value through the several exploration and development phases. The purpose being to assess the progressive value of the mineral asset in agreement with the information and data cumulated through the different steps from exploration to project approval. This paper establishes the value of a copper mineral deposit through their successive phases from exploration to feasibility and approval using the options’ binomial nodes framework. Results are applied to two copper negotiations for method validation. 展开更多
关键词 Mine Value Exploration Phases Binomial Nodes Copper Deposits Method Validation
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Avian malaria,haematocrit,and body condition in invasive wetland passerines settled in southwestern Spain
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作者 Jaime Muriel Luz Garcia-Longoria +2 位作者 Sergio Magallanes Juan Antonio Ortiz Alfonso Marzal 《Avian Research》 SCIE CSCD 2023年第1期99-107,共9页
Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds.Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native pas... Avian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds.Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native passerines,with exotic species underrepresented.However,introduced species may carry on and spread new pathogens to native species,and play a role on parasite transmission cycle in invaded bird communities as pathogen reservoir.Here,we molecularly assess the prevalence and diversity of haemosporidian parasites in three introduced wetland passerines(the Red Avadavat Amandava amandava,the Yellow-crowned Bishop Euplectes afer,and the Common Waxbill Estrilda astrild)captured during the same season in southwestern Spain.We also explored the relation between parasite infection,body condition,haematocrit,and uropygial gland volume.We detected an overall parasite prevalence of 3.55%,where Common Waxbills showed higher prevalence(6.94%)than Red Avadavats(1.51%).None Yellow-crowned Bishops were infected with haemosporidians.Almost 60%of infections were caused by Leucocytozoon,and about 40%by Plasmodium.We identified four unique lineages of Plasmodium and three of Leucocytozoon.Moreover,91%of the identified host-parasite interactions represented new host records for these haemosporidian parasites.Parasite infection was not related to body condition,haematocrit,and uropygial gland volume of the wetland passerines.Haematocrit values varied seasonally among bird species.Additionally,haematocrit was positively related to body condition in the Yellow-crowned Bishops,but not in the other species.Red Avadavats had higher haematocrit levels than Yellow-crowned Bishops,whereas Common Waxbills showed the lower haematocrit values.The uropygial gland volume was positively correlated with body condition in all bird species.Common Waxbills showed higher uropygial gland volumes related to their body size than birds from other two species.These outcomes highlight the importance of exotic invasive species in the transmission dynamics of haemosporidian parasites. 展开更多
关键词 Avian malaria Exotic species Introduced birds LEUCOCYTOZOON PLASMODIUM Uropygial gland
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Quantum Codes Do Not Increase Fidelity against Isotropic Errors
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作者 Jesús Lacalle Luis Miguel Pozo-Coronado +1 位作者 André Luiz Fonseca de Oliveira Rafael Martín-Cuevas 《Journal of Applied Mathematics and Physics》 2023年第2期555-571,共17页
In this article, we study the ability of error-correcting quantum codes to increase the fidelity of quantum states throughout a quantum computation. We analyze arbitrary quantum codes that encode all qubits involved i... In this article, we study the ability of error-correcting quantum codes to increase the fidelity of quantum states throughout a quantum computation. We analyze arbitrary quantum codes that encode all qubits involved in the computation, and we study the evolution of n-qubit fidelity from the end of one application of the correcting circuit to the end of the next application. We assume that the correcting circuit does not introduce new errors, that it does not increase the execution time (i.e. its application takes zero seconds) and that quantum errors are isotropic. We show that the quantum code increases the fidelity of the states perturbed by quantum errors but that this improvement is not enough to justify the use of quantum codes. Namely, we prove that, taking into account that the time interval between the application of the two corrections is multiplied (at least) by the number of qubits n (due to the coding), the best option is not to use quantum codes, since the fidelity of the uncoded state over a time interval n times smaller is greater than that of the state resulting from the quantum code correction. 展开更多
关键词 Quantum Error Correcting Codes Isotropic Quantum Computing Errors Quantum Computing Error Fidelity Quantum Computing Error Variance
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Air Quality Estimation Using Nonhomogeneous Markov Chains: A Case Study Comparing Two Rules Applied to Mexico City Data
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作者 Eliane R. Rodrigues Juan A. Cruz-Juárez +1 位作者 Hortensia J. Reyes-Cervantes Guadalupe Tzintzun 《Journal of Environmental Protection》 2023年第7期561-582,共22页
A nonhomogeneous Markov chain is applied to the study of the air quality classification in Mexico City when the so-called criterion pollutants are used. We consider the indices associated with air quality using two re... A nonhomogeneous Markov chain is applied to the study of the air quality classification in Mexico City when the so-called criterion pollutants are used. We consider the indices associated with air quality using two regulations where different ways of classification are taken into account. Parameters of the model are the initial and transition probabilities of the chain. They are estimated under the Bayesian point of view through samples generated directly from the corresponding posterior distributions. Using the estimated parameters, the probability of having an air quality index in a given hour of the day is obtained. 展开更多
关键词 Air Quality Index Air Pollution Mexico City Nonhomogeneous Markov Chains Bayesian Inference
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Thinking outside the black box:are the brain endothelial cells the new main target in Alzheimer's disease?
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作者 Enrique Estudillo Adolfo López-Ornelas +3 位作者 Alejandro Rodríguez-Oviedo Neptali Gutiérrez de la Cruz Marco Antonio Vargas-Hernández Adriana Jiménez 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2592-2598,共7页
The blood-brain barrier is the interface through which the brain interacts with the milieu and consists mainly of a sophisticated network of brain endothelial cells that forms blood vessels and selectively moves molec... The blood-brain barrier is the interface through which the brain interacts with the milieu and consists mainly of a sophisticated network of brain endothelial cells that forms blood vessels and selectively moves molecules inside and outside the brain through multiple mechanisms of transport.Although brain endothelial cell function is crucial for brain homeostasis,their role in neurodegenerative diseases has historically not been considered with the same importance as other brain cells such as microglia,astroglia,neurons,or even molecules such as amyloid beta,Tau,or alpha-synuclein.Alzheimer's disease is the most common neurodegenerative disease,and brain endothelial cell dysfunction has been reported by several groups.However,its impairment has barely been considered as a potential therapeutic target.Here we review the most recent advances in the relationship between Alzheimer's disease and brain endothelial cells commitment and analyze the possible mechanisms through which their alterations contribute to this neurodegenerative disease,highlighting their inflammatory phenotype and the possibility of an impaired secretory pattern of brain endothelial cells that could contribute to the progression of this ailment.Finally,we discuss why shall brain endothelial cells be appreciated as a therapeutic target instead of solely an obstacle for delivering treatments to the injured brain in Alzheimer's disease. 展开更多
关键词 DEMENTIA endothelial cells NEURODEGENERATION NEUROINFLAMMATION neuronal death paracellular transport transcellular transport
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Metabolic complications in liver transplant recipients 被引量:10
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作者 Miguel Jiménez-Pérez Rocío González-Grande +2 位作者 Edith Omonte Guzmán Víctor Amo Trillo Juan Miguel Rodrigo López 《World Journal of Gastroenterology》 SCIE CAS 2016年第28期6416-6423,共8页
The metabolic syndrome(MS), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, wi... The metabolic syndrome(MS), which includes obesity,dyslipidaemia, hypertension and hyperglycaemia according to the most widely accepted definitions now used, is one of the most common post-transplant complications, with a prevalence of 44%-58%. The MS, together with the immunosuppression, is considered the main risk factor for the development of cardiovascular disease(CVD) in transplant recipients, which in turn accounts for 19%-42% of all deaths unrelated to the graft. The presence of MS represents a relative risk for the development of CVD and death of 1.78. On the other hand, non-alcoholic fatty liver disease(NAFLD), considered as the manifestation of the MS in the liver, is now the second leading reason for liver transplantation in the United States after hepatitis C and alcohol. NAFLD has a high rate of recurrence in the liver graft and a direct relation with the worsening of other metabolic disorders, such as insulin resistance or diabetes mellitus. Consequently, it is vitally important to identify and treat as soon as possible such modifiable factors as hypertension, overweight, hyperlipidaemia or diabetes in transplanted patients to thus minimise the impact on patient survival. Additionally, steroid-free regimens are favoured, with minimal immunosuppression to limit the possible effects on the development of the MS. 展开更多
关键词 METABOLIC SYNDROME LIVER TRANSPLANTATION immunosuppressions Risk factors non-alcoholic FATTY LIVER d
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Biliary acute pancreatitis:a review 被引量:6
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作者 Osvaldo M.Tiscomia Susana Hamamura +4 位作者 Enriqueta S.deLehmann Graciela Otero Hipolito Waisman Patricia Tiscornia-Wasserman Simmy Bank 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第2期157-168,共12页
INTRODUCTIONIt is axiomatic that the most effective and soundlybased plan of treatment of any disorder is one aimedat the mechanism or mechanisms responsible for itsdevelopment.This basic notion,coupled withrecent rep... INTRODUCTIONIt is axiomatic that the most effective and soundlybased plan of treatment of any disorder is one aimedat the mechanism or mechanisms responsible for itsdevelopment.This basic notion,coupled withrecent reports in which,surprisingly there is atotal lack of reference to the probable involvementof autonomic-arc-reflexes in the 展开更多
关键词 cholelithiasis/physiopathology pancreatitis/physiopathology BILE REFLUX common BILE duct SPHINCTEROTOMY endoscopic
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Gallbladder tuberculosis: False-positive PET diagnosis of gallbladder cancer 被引量:5
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作者 JM Ramia K Muffak +3 位作者 A Fernández J Villar D Garrote JA Ferron 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第40期6559-6560,共2页
Gallbladder tuberculosis (GT) is an extremely rare disease, and very few cases have been reported in the literature. The first case of GT was described in 1870 by Gaucher. A correct preoperative diagnosis of GT is unu... Gallbladder tuberculosis (GT) is an extremely rare disease, and very few cases have been reported in the literature. The first case of GT was described in 1870 by Gaucher. A correct preoperative diagnosis of GT is unusual, and it is frequently confused with various gallbladder diseases. We present a new case of a patient who underwent surgery with the preoperative diagnosis of gallbladder cancer after a false positive positron emission tomography scan in the diagnostic work-up. 展开更多
关键词 胆囊疾病 结核 病理 治疗 临床
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Hepatoprotective properties of oleanolic and ursolic acids in anti-tubercular drug-induced liver damage 被引量:10
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作者 Gabriel A.Gutiérrez-Rebolledo Georgina A.Siordia-Reyes +1 位作者 Mariana Meckes-Fischer Adelina Jiménez-Arellanes 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第7期625-632,共8页
Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c ... Objective:To estimate to what extent the mixture of ursolic acid and oleanolic acid,in addition to the antitubercular standard regime,affects the hepatotoxicity profile.Methods:Liver injury was induced in male BALB/c mice by administering,per os and daily for 11 weeks,a combination of anti-Tubercular(anti-TB) agents Rifampicin(10 mg/kg),Isoniazid(10 mg/kg),and Pyrazinamide(30 mg/kg).The ursolic acid and oleanolic acid mixture at doses of 100 or 200 μg/mouse/day was subcutaneously injected throughout the entire study period(11 weeks).Biochemical and hematological analysis was supplemented by liver histological examination.Results:Animals treated with the mixture of triterpenic acids exhibited significantly decreased aspartate transaminase and alanine aminotransferase levels and amelioration of the histopathological alterations produced by the anti-TB drugs.Conclusions:The triterpene mixture is able to prevent the steatosis induced by the anti-TB drugs. 展开更多
关键词 Ursolic ACID Oleanolic ACID Hepatoprotector effect ANTITUBERCULAR DRUGS TRITERPENES
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Morphometric, Physicochemical, Thermal, and Rheological Properties of Rice (<i>Oryza sativa</i>L.) Cultivars <i>Indica ×Japonica</i> 被引量:2
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作者 Laura Elizabeth Morales-Martínez Luis Arturo Bello-Pérez +2 位作者 Mirna María Sánchez-Rivera Elsa Ventura-Zapata Antonio Ruperto Jiménez-Aparicio 《Food and Nutrition Sciences》 2014年第3期271-279,共9页
The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate... The anther culture technical was applied to produce haploid lines of rice (Oryza sativa L.). The hybrids (K/ A92VM061, K/A92VM067, K/A92VM0611, K/A92VM719, K/A92VM720 and K/A92VM721) were obtained in order to generate new varieties from Indica and Japonica cultivars. Morphometric parameters of the grains were evaluated by image analysis. Flours were prepared from the whole rice grains and physicochemical, thermal and rheological properties, X-ray diffraction pattern and evaluation of color using the CIELAB system were assessed. The hybrids lines showed long (061, 611, 721), medium (719 and 720) and short (067) grains. The rice samples presented lipids (2.6% - 3.2%), protein (11% - 15%), total dietary fiber (8.4% - 10.2%), total starch (65% - 74%) and apparent amylose (5% - 32%) contents. Gelatinization temperature (Tp) was found in the range of 66.1℃ - 79.4℃ with enthalpy (ΔH) value between 3.4 - 8.1 J/g. The retrogradation parameters (temperature and ΔH) were lower than those for gelatinization in all samples. The rice samples presented A-type X-ray diffraction pattern. Rice pastes showed a non-Newtonian behavior and the brightness (L*) characterize the color of the samples. Hybrid rice grains presented morphometric properties more similar to Japonica than Indica variety. Rice hybrid had higher protein content than Indica variety. Apparent amylose, viscosity and gelatinization temperature varied significantly among hybrids and varieties. 展开更多
关键词 Brown RICE Hybrid Grains MORPHOMETRIC Parameters GELATINIZATION Temperature Flow Behavior PASTING Viscosity
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CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS 被引量:3
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作者 丁小丽 Juan J.NIETO 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1003-1013,共11页
Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The ex... Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results. 展开更多
关键词 CONTROLLABILITY OPTIMALITY neutral equations different fractional orders
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Bifid pancreatic tail as cause of acute pancreatitis 被引量:1
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作者 Hanna Rafaela Ferreira Dalla Pria Rafael Andrade Santiago +1 位作者 Fernanda Garozzo Velloni Giuseppe D’ippolito 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第5期480-481,共2页
To the Editor:Wepresentacaseofa22-year-oldwomanwithrecurrent episodes of acute pancreatitis. The patient had no known risk factors such as history of alcoholism, smoking, pre-existing medical conditions, family member... To the Editor:Wepresentacaseofa22-year-oldwomanwithrecurrent episodes of acute pancreatitis. The patient had no known risk factors such as history of alcoholism, smoking, pre-existing medical conditions, family members with pancreatitis, autoimmune disease orregularuseofmedications.Duringthelastepisode,anamylase peak (1175 U/L) and increased inflammatory markers were de- 展开更多
关键词 pre-existing medicall DILATATION or CHOLELITHIASIS
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High Light Intensity Increases the CAM Expression in “MD-2” Micro-Propagated Pineapple Plants at the End of the Acclimatization Stage 被引量:2
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作者 René C. Rodríguez-Escriba Romelio Rodríguez +6 位作者 Dariel López Gustavo Y. Lorente Yaima Pino Carlos E. Aragón Yolanda Garza Florencio E. Podestá Justo L. González-Olmedo 《American Journal of Plant Sciences》 2015年第19期3109-3118,共10页
This work describes the evaluation of morpho-physiological and biochemical changes in “MD-2” micro-propagated pineapple plants (Ananas comosus (L.) Merr.) grown after 30 days under low light intensity (LL, greenhous... This work describes the evaluation of morpho-physiological and biochemical changes in “MD-2” micro-propagated pineapple plants (Ananas comosus (L.) Merr.) grown after 30 days under low light intensity (LL, greenhouse light conditions at 250 μmol·m-2·s-1) or high light intensity (HL, field light conditions at 800 μmol·m-2·s-1). Gas exchange, leaf pH, protein content and superoxide dismutase activity (SOD) (EC 1.15.1.1) were measured every 3 h during one day. Chlorophylls content and succulence index (SI) were determined at 9 h. Results showed significant differences in CO2 exchange rates, with a maximum occurring at 6 h (3.00 and 8.25 μmol CO2 m-2·s-1 for leaves under LL and HL conditions respectively). Plants under HL conditions had higher CO2 uptake and lower pH values between 0 h and 6 h respective to LL plants. The maximum pH value was attained 3 h before in HL plants. Leaf SI was increased and chlorophyll content decreased by HL conditions. SOD activity was higher in plants under HL conditions, near doubling those of LL plants at 18 h (2.8 versus 1.5 U·mg-1 Protein respectively). Both groups showed a typical CAM phenotype, but it was stronger in HL conditions, which may confer these plants with a better acclimation to transfer to the field. 展开更多
关键词 Crassulacean Acid Metabolism HARDENING STAGE Ex VITRO Vitroplants Gaseous Exchange
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Technique to Obtain Mitotic Chromosomes of <i>Conyza bonariensis</i>L. Cronquist (Asteraceae) 被引量:1
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作者 Juliana Maria de Paula Cecília Alzira Ferreira Pinto-Maglio 《American Journal of Plant Sciences》 2015年第9期1466-1474,共9页
Cytogenetic analysis requires cytological preparations that unequivocally reveal the chromosome number and permit optimal visualizations of chromosome morphology for the construction of karyotypes and ideograms. Chrom... Cytogenetic analysis requires cytological preparations that unequivocally reveal the chromosome number and permit optimal visualizations of chromosome morphology for the construction of karyotypes and ideograms. Chromosomal characterization is possible only by establishing these two parameters. To cytogenetically characterize the weed Conyza bonariensis (L.) Cronquist (Asteraceae), it was necessary to improve cytological analysis techniques to obtain optimal results. This species belongs to a genus whose plants have wide phenotypic plasticity. These plants can be morphologically differentiated by other types of analysis, and thus the application of this technique will serve as a reference for cytogenetical analysis of other groups of plants that have cytogenetic characteristics similar to those of C. bonariensis. The methodology described here highlights three main protocol steps: 1) root tip collection from newly germinated seed radicles and from young root tips of mature plants, 2) pretreatment of meristems with antimitotic agents, both isolated and combined, and 3) acid and enzymatic hydrolytic processes. 展开更多
关键词 HAIRY Fleabane CYTOGENETICS Chromosomes WEED
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Convergence of Invariant Measures of Truncation Approximations to Markov Processes 被引量:2
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作者 Andrew G. Hart Richard L. Tweedie 《Applied Mathematics》 2012年第12期2205-2215,共11页
Let Q be the Q-matrix of an irreducible, positive recurrent Markov process on a countable state space. We show that, under a number of conditions, the stationary distributions of the n × n north-west corner augme... Let Q be the Q-matrix of an irreducible, positive recurrent Markov process on a countable state space. We show that, under a number of conditions, the stationary distributions of the n × n north-west corner augmentations of Q converge in total variation to the stationary distribution of the process. Two conditions guaranteeing such convergence include exponential ergodicity and stochastic monotonicity of the process. The same also holds for processes dominated by a stochastically monotone Markov process. In addition, we shall show that finite perturbations of stochastically monotone processes may be viewed as being dominated by a stochastically monotone process, thus extending the scope of these results to a larger class of processes. Consequently, the augmentation method provides an attractive, intuitive method for approximating the stationary distributions of a large class of Markov processes on countably infinite state spaces from a finite amount of known information. 展开更多
关键词 INVARIANT Measure TRUNCATION Approximation Augmentation EXPONENTIAL ERGODICITY Stochastic MONOTONICITY Markov Process
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Land cover changes and fragmentation in mountain neotropical ecosystems of Oaxaca, Mexico under community forest management 被引量:4
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作者 Rafael M~a Navarro Cerrillo Dennis J.Esteves Vieira +2 位作者 Susana Ochoa-Gaona Bernardus H.J.de Jong M~a del Mar Delgado Serrano 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第1期143-155,共13页
Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat im... Changes in land cover have a direct impact on forest ecosystem goods and services. In this study, changes in land cover in Sierra de Juarez–Oaxaca ecosystems were estimated using a consistent processing of Landsat images and OBIA methodology. Additionally, landscape analyses using FRAGSTAT were conducted. In 2014, Sierra de Juarez–Oaxaca was covered by approximately 84% of forests, mainly pine-oak and cloud forests. After extensive deforestation until 2001, this trend was reversed and the forest cover surface area in 2014 was slightly higher than in 1979. The comparison of the landscape structure of the forested and agricultural lands suggests an increase in habitat heterogeneity. However, interspersion and juxtaposition indices, showing the patch shape by patch area and perimeter, were similar throughout the study period(1979–2014). Social and economic drivers can explain this situation: namely, community organization, forest enterprises, payment for ecosystem services programs, and changes of agricultural activity. Communities in the Sierra of Oaxaca have reforested degraded lands, created community forest enterprises, and preserved the forest under conservation schemes like those proposed by the Mexican payment for ecosystem services programs. However, their sustainable management faces internal challenges and has become highly dependent on political and institutional decisions beyond their control. 展开更多
关键词 Tropical and TEMPERATE FORESTS Social forestry Land USES segmentation OBIA FRAGSTAT
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