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Agricultural Sciences 2013年第9期4卷 491-498页

作者： Hector Sotelo-nava Oscar Gabriel Villegas-Torres Martha Lilia Domínguez-Patino Francisco Perdomo-Roldán Elías Hernández Castro agustín damián nava Margarita Ramos García Facultad de Ciencias Agropecuarias Universidad Autónoma del Estado de MorelosCuernavacaMexico Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosCuernavacaMexico Unidad Academica de Ciencias Agropecuarias y Ambientales Universidad Autónoma de GuerreroIgualaMexico

In two contrasting agricultural ecohabitats (agrohabitats) in the avocado production area in the municipality of Cuernavaca, Morelos, an analysis of nutrimental status, soil fertility and water quality was conducted to measure soil fertility levels and to determine the nutrimental state of the trees. The “Hass” variety avocado groves studied had an average age of 8 years;the first grove was planted in an acrisol soil (1700 to 1900 meters above mean sea level [mamsl]);the second, in an andosol soil (1200 to 1700 mamsl). In each agrohabitat, tests were performed to determine the soil’s physical and chemical characteristics. The physical and chemical characteristics of the soils of this zone differ as do the nutrimental states of the avocado trees in the two agrohabitats. The trees showed excessive concentration of Ca, Fe, S, Z and Mg. The indices of Deviation from Optimal Percentage (DOP) in the two agrohabitats showed different nutrimental requirements;nevertheless, they were low and very near to zero, 14.218 and 13.350 respectively. The water used for the agricultural irrigation was low in salinity and sodium content and thus may be used for the agricultural irrigation without restrictions.

关键词： Avocado nutrimental Imbalance Index Diagnosis nutrimental Status nutrients

Hepatic lipid metabolism changes in short-and long-term prehepatic portal hypertensive rats

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World Journal of Gastroenterology 2006年第42期12卷 6828-6834页

作者： Maria-Angeles Aller Elena Vara Cruz García Maria-Paz nava Alejandra Angulo Fernando Sánchez-Patán Ana Calderón Patri Vergara Jaime Arias SurgeryⅠ Department School of Medicine Complutense University of Madrid Spain Biochemical and Molecular Biology Department School of Medicine Complutense University of Madrid Spain Animal Physiology Department (Physiology Ⅱ) School of Biological Sciences Complutense University of Madrid Spain Physiology Unit. Veterinary School Autonoma University of Barcelona Bellaterra Catalua Spain

AIM: To verify the impairment of the hepatic lipid metabolism in prehepatic portal hypertension. METHODS: The concentrations of free fatty acids, diacylglycerol, triglycerides, and phospholipids were assayed by using D-[U-14C] glucose incorporation in the different lipid fractions and thin-layer chromatography and cholesterol was measured by spectrophotometry, in liver samples of Wistar rats with partial portal vein ligation at short- (1 mo) and long-term (1 year) (i.e. portal hypertensive rats) and the control rats. RESULTS: In the portal hypertensive rats, liver phospholipid synthesis significantly decreased (7.42 ± 0.50 vs 4.70 ± 0.44 nCi/g protein; P nd was associated with an increased synthesis of free fatty acids (2.08 ± 0.14 vs 3.36 ± 0.33 nCi/g protein; P nCi/g protein), triglycerides (2.40 ± 0.30 vs 4.49 ± 0.15 nCi/g protein) and cholesterol (24.28 ± 2.12 vs 57.66 ± 3.26 mg/g protein; P nCLUSIOn: Prehepatic portal hypertension in rats impairs the liver lipid metabolism. This impairment consists in an increase in lipid deposits (triglycerides,diacylglycerol and cholesterol) in the liver, accompanied by a decrease in phospholipid synthesis.

关键词： Portal hypertension Free fatty acids Diacylglycerides Triglycerides Phospholipids Cholesterol

Role of the intestinal barrier in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 401-407页

作者： Mike G Laukoetter Porfirio nava Asma nusrat Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States Department of General Surgery University of Muenster Muenster 48149 Germany Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States

A critical function of the intestinal mucosa is to form a barrier that separates luminal contents from the interstitium. The single layer of intestinal epithelial cells (IECs) serves as a dynamic interface between the host and its environment. Cell polarity and structural properties of the epithelium is complex and is important in the development of epithelial barrier function. Epithelial cells associate with each other via a series of intercellular junctions. The apical most intercellular junctional complex referred to as the Apical Junction Complex (AJC) is important in not only cell-cell recognition, but also in the regulation of paracellular movement of fluid and solutes. Defects in the intestinal epithelial barrier function have been observed in a number of intestinal disorders such as inflammatory bowel disease (IBD). It is now becoming evident that an aberrant epithelial barrier function plays a central role in the pathophysiology of IBD. Thus, a better understanding of the intestinal epithelial barrier structure and function in healthy and disease states such as IBD will foster new ideas for the development of therapies for such chronic disorders.

关键词： Intestine Barrier function Tight Junction InflammatorY bowel disease Crohn's disease Ulcerativecolitis

Identification of Arceuthobium globosum using unmanned aerial vehicle images in a high mountain forest of central Mexico

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Journal of Forestry Research 2020年第5期31卷 1759-1771页

作者： Luis A.Leon-Banuelos Angel R.Endara-Agramont William Gomez-Demetrio Carlos G.Martınez-Garcıa E.Gabino nava-Bernal 50000 TolucaMexicoMexico

The identification of forests infested by parasitic plants is important for the design of appropriate control and prevention *** images and geographic information systems are commonly used to analyze the presence of pest and parasitic plants in the *** there is a need for finer *** the last decade,the use of unmanned aerial vehicles has become increasingly common for capturing aerial images(n RGB values(Red,Green and Blue)through the colorimetric ranges for use in identification of Yellow Dwarf Mistletoe(YDM)(Arceuthobium globosum)in aerial images taken in a forest of central Mexico via a programmed *** tonalities of YDM were classified according to its phenological stages,***(young stage),yellow(adult stage),and brown(senescence stage),considering two light intensities,sunny and ***-parametric tests were used in statistical *** Spearman test showed significant negative correlation(pn phenological stage and colour,indicating that lower RGB values were associated with greater *** differences between groups were analysed using Kruskal–Wallis(pnd Mann–Whitney tests(pntified the presence and predominant colours of YDM according to its phenological stage.

关键词： Colorimetric analysis RGB Pinus hartweggi Parasitic plants Remote sensing

Uniformity in premating reproductive isolation along an intraspecific cline

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Current Zoology 2018年第5期64卷 641-652页

作者： Jeanne Marie ROBERTSOn Roman nava Andrds VEGA Kristine KAISER Department of Biology California State University Northridge 18111 Nordhoff Street Northridge CA 91330-8303 USA naturel History Museum of Los Angeles County 900 Exposition Boulevard Los Angeles CA 90007 USA Department of Biology San Diego State University 5500 Campanile Drive San Diego CA 92116 USA AMBICOR 400 E. 75 S. 75 E. de la Municipalidad de Tibas Tibas Costa Rica

Premating reproductive isolation （RI） may reduce gene flow across populations that have differentiated in traits important for mate choice. Examining RI across genetic and phenotypic clines can inform the fundamental evolutionary processes that underlie population and lineage differentiation. We conducted female mate-choice studies across an intraspecific red-eyed treefrog cline in Costa Rica and Panama with 2 specific aims：（1） to characterize RI across the cline and examine the relationship between premating RI and genetic and phenotypic distance and （2） to evaluate our results within a broader evolutionary and taxonomic perspective through examination of other RI studies. We found that female red-eyed treefrogs prefer local males relative to non-local males, indicating that some premating RI has evolved in this system, but that preference strength is not associated with phenotypic or geographic distance. Our analysis of 65 other studies revealed no clear pattern between the strength of RI and geographic distribution （allopatry, parapatry, cline） or phenotypic distance, but revealed extreme variation and overlap in levels of intra- and interspecific levels of RI. This work contributes to a growing body of literature that examines intraspecific RI across a cline to understand the selective processes that shape evolutionary patterns at the earliest stages of divergence.

关键词： advertisement call anuran color pattern courtship signals mate choice.

Automatic Detection of nephrops norvegicus Burrows from Underwater Imagery Using Deep Learning

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Computers, Materials & Continua 2022年第3期70卷 5321-5344页

作者： Atif naseer Enrique nava Baro Sultan Daud Khan Yolanda Vila Jennifer Doyle ETSI Telecomunicación Universidad deMálagaMálaga29071Spain Department of Computer Science National University of TechnologyIslamabad44000Pakistan Instituto Espanol de Oceanografía Centro Oceanográfico de CádizCádiz39004Spain Marine Institute Rinville OranmoreIreland

The norway lobster,nephrops norvegicus,is one of the main commercial crustacean fisheries in *** abundance of nephrops norvegicus stocks is assessed based on identifying and counting the burrows where they live from underwater videos collected by camera systems mounted on *** Spanish Oceanographic Institute(IEO)andMarine Institute Ireland(MIIreland)conducts annual underwater television surveys(UWTV)to estimate the total abundance of nephrops within the specified area,with a coefficient of variation(CV)or relative standard error of less than 20%.Currently,the identification and counting of the nephrops burrows are carried out manually by the marine *** is quite a time-consuming *** a solution,we propose an automated system based on deep neural networks that automatically detects and counts the nephrops burrows in video footage with high *** proposed system introduces a deep-learning-based automated way to identify and classify the nephrops *** research work uses the current state-of-the-art Faster RCnn models Inceptionv2 and Mobilenetv2 for object detection and *** conduct experiments on two data sets,namely,the Smalls nephrops survey(FU 22)and Cadiz nephrops survey(FU 30),collected by Marine Institute Ireland and Spanish Oceanographic Institute,*** the results,we observe that the Inception model achieved a higher precision and recall rate than *** best mean Average Precision(mAP)recorded by the Inception model is 81.61%compared to Mobilenet,which achieves the best mAP of 75.12%.

关键词： Faster RCnn computer vision nephrops norvegicus nephrops norvegicus stock assessment underwater videos classification

A Temporal Domain Decomposition Algorithmic Scheme for Large-Scale Dynamic Traffic Assignment

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International Journal of Transportation Science and Technology 2012年第1期1卷 1-24页

作者： Eric J.nava Yi-Chang Chiu Department of Civil Engineering and Engineering Mechanics University of Arizona1209 E 2nd St.TucsonAZUSA

With emergent interest of Simulation-Based Dynamic Traffic Assignment(SBDTA)in the field of transportation network modeling,deployment of SBDTA models for traffic operations and transportation planning have increased significantly in recent *** parallel,research and development of innovative approaches of the SBDTA model have enhanced the quality of both the assignment component,i.e,improvement of convergence quality of the Dynamic User Equilibrium(DUE)problem,and the traffic simulation ***,computational requirement remains to be one of the great challenges for DTA implementations on large-scale networks with a long analysis *** paper presents a temporal decomposition scheme for large spatial-and temporal-scale dynamic traffic assignment,in which the entire analysis period is divided into *** assignment is performed sequentially in each Epoch,thus improving the model scalability and confining the peak run-time memory requirement regardless of the total analysis period.A proposed self-turning scheme adaptively searches for the run-time-optimal Epoch setting during iterations regardless of the characteristics of the modeled *** numerical experiments confirm the promising performance of the proposed algorithmic schemes.

关键词： dynamic traffic assignment method of isochronal vehicle assignment simulation computational efficiency large scale

Analysis of Fragmentation Processes in High-Mountain Forests of the Centre of Mexico

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American Journal of Plant Sciences 2013年第3期4卷 697-704页

作者： Angel Rolando Endara-Agramont Rafael Calderón-Contreras Gabino nava-Bernal Sergio Franco-Maass Instituto de Ciencias Agropecuarias y Rurales Toluca México Universidad Autónoma Metropolitana D. F. México México

High-mountain forests (>3500 masl) are the main supplier of environmental services to Mexico City and its metropolitan area. Taking as a study case the nevado de Toluca national Park, this article focuses on the considerable reduction on the density of its forest cover, characterised by disturbances in the structure and dynamics of Pinus hartwegii. This specie is located towards the upper limits of the altitudinal gradient (3500 - 4100 masl) constituting the only pine species in the world capable to be established in those extreme environmental conditions. The information was collected through the implementation of 30 Sampling Plots (SP) of 20 × 50 mts (1000 m2) in three forest density categories: dense, semi-dense and fragmented. For each forest category, all trees ≥2.5 cm DBH were measured in 10 SPs. The measurement variables were DBH, total and commercial height, forest health and forest extraction. The results show the abundance of dense, semi-dense and fragmented forest (336, 202 and 150 trees/Ha-1), with extraction percentages of 11%, 20% and 33% respectively. The horizontal structure distribution shows the shape of an inverted J for the three conditions. However, the phytosanitary conditions of the semi-dense forests (83% infested trees) and fragmented (63% infested trees), do not guaranties the survival of the adult trees, implying an intensification of the fragmentation process for the next decade;given the reduction of the regeneration patterns due to the lack of healthy tree breeding.

关键词： High-Mountain Forests Fragmentation Forest Structure Forest Health

Advancing immunosuppression in liver transplantation: A narrative review

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 441-448页

作者： Samuele Iesari Francesca Laura nava Ilaria Elena Zais Laurent Coubeau Mariano Ferraresso Evaldo Favi Jan Lerut General Surgery and Kidney Transplantation Fondazione IRCCS Ca’Granda Ospedale Maggiore Policlinico15 Via della Commenda20122 MilanItaly Institut de Recherche Expérimentale et Clinique Universitécatholique de Louvain10 Avenue Hippocrate1200 BrusselsBelgium Service de Chirurgie et Transplantation Abdominale Cliniques Universitaires Saint-Luc55 Avenue Hippocrate1200 BrusselsBelgium Department of Clinical Sciences and Community Health Universitàdegli Studi di Milano19 Via della Commenda20122 MilanItaly

Immunosuppression is essential to ensure recipient and graft survivals after liver transplantation(LT). However, our understanding and management of the immune system remain suboptimal. Current immunosuppressive therapy cannot selectively inhibit the graft-specific immune response and entails a significant risk of serious side effects, i.e., among others, de novo cancers, infections, cardiovascular events, renal failure, metabolic syndrome, and late graft fibrosis, with progressive loss of graft function. Pharmacological research, aimed to develop alternative immunosuppressive agents in LT, is behind other solidorgan transplantation subspecialties, and, therefore, the development of new compounds and strategies should get priority in LT. The research trajectories cover mechanisms to induce T-cell exhaustion, to inhibit co-stimulation, to mitigate non-antigen-specific inflammatory response, and, lastly, to minimize the development and action of donor-specific antibodies. Moreover, while cellular modulation techniques are complex, active research is underway to foster the action of T-regulatory cells, to induce tolerogenic dendritic cells, and to promote the function of B-regulatory cells. We herein discuss current lines of research in clinical immunosuppression, particularly focusing on possible applications in the LT setting.

关键词： Liver transplantation Immunosuppression Drug development Long-term results Clinical operational tolerance

nanofibrous nerve conduits for repair of 30-mm-long sciatic nerve defects

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neural Regeneration Research 2013年第24期8卷 2266-2274页

作者： Esmaeil Biazar Saeed Heidari Keshel Majid Pouya Hadi Rad Melody Omrani nava Mohammad Azarbakhsh Shirin Hooshmand Department of Biomaterial Engineering Tonekabon Branch Islamic Azad University Student Research Committee Proteomics Research Center Faculty of Paramedical Sciences Shahid Beheshti University of Medical Sciences Department of Tissue Engineering School of Advanced Technologies in Medicine Tehran University of Medical Sciences Department of Medical Sciences Tonekabon Branch Islamic Azad University Faculty of Medical Sciences Babol University of Medical Sciences

It has been confirmed that nanofibrous poly（3-hydroxybutyrate-co-3-hydroxyvalerate） nerve conduit can promote peripheral nerve regeneration in rats. However, its efficiency in repair of over 30-mm-long sciatic nerve defects needs to be assessed. In this study, we used a nanofibrous poly（3-hydroxybutyrate-co-3-hydroxyvalerate） nerve conduit to bridge a 30-mm-long gap in the rat sciatic nerve. At 4 months after nerve conduit implantation, regenerated nerves were macroscopi- cally observed and histologically assessed. In the nanofibrous graft, the rat sciatic nerve trunk had been reconstructed by restoration of nerve continuity and formation of myelinated nerve fiber. There were Schwann cells and glial cells in the regenerated nerves. Masson＇s trichrome staining showed that there were no pathological changes in the size and structure of gastrocnemius muscle cells on the operated side of rats. These findings suggest that nanofibrous poly（3-hydroxybutyrate-co-3- hydroxyvalerate） nerve conduit is suitable for repair of long-segment sciatic nerve defects.

关键词： neural regeneration peripheral nerve injury sciatic nerve artificial conduit nanofiber poly(3-hydr-oxybutyrate-co-3-hydroxyvalerate) macroscopic observation histology grants-supported paper neuroregeneration