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Effects of Hedera helix *** on the understory early regeneration in an oak temperate forest in Mexico City

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Ecological Processes 2023年第1期12卷 438-449页

作者： Héctor Adrián Jiménez-Hernández Leticia Bonilla-Valencia Yuriana Martínez-Orea Mara Jessica Zamora-Almazan francisco Javier Espinosa-García Silvia Castillo-Argüero Facultad de Ciencias Universidad Nacional Autónoma de MéxicoMexico CityMexico Instituto de Investigaciones en Ecosistemas y Sustentabilidad Universidad Nacional Autónoma de MéxicoMichoacánMexico

Background Hedera helix *** an invasive weed species introduced in several regions of the world,so it is relevant to study its effects on the plant community and the changes occurring after its *** established invaded(with/without removal of ***)and non-invaded(with/without removal of the understory)plots to compare some community attributes in an oak forest in Mexico City and monitored them every 2 months for 1 year,taking soil samples to compare some edaphic variables between the *** invasive species negatively affect natural regenera-tion,seedlings of native species would be less abundant in plots invaded by *** than in the non-invaded *** invasive species modify the soil microbiota through exudates and often allelochemicals,soil chemical variables would differ between invaded and non-invaded *** The abundance of native species was lower in the invaded plots,but the richness and diversity of species were not statistically *** composition of the two invaded plots was similar to each other and more alike to that of the non-invaded *** species composition of the invaded plots was associated with soil potassium and phosphorus concentrations,whereas that of the non-invaded plots was more associated with soil nitrogen *** Following the removal of ***,several native species were registered,leading to a similar species composition as in the non-invaded plots,suggesting that some vegetation recovery can be expected following *** removal in 1 year.

关键词： Ivy Invasive plant Mechanical control Diversity Species composition

Conservation and variability of hepatitis B core at different chronic hepatitis stages

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World Journal of Gastroenterology 2020年第20期26卷 2584-2598页

作者： Marcal Yll Maria Francesca Cortese Mercedes Guerrero-Murillo Gerard Orriols Josep Gregori Rosario Casillas Carolina González Sara Sopena Cristina Godoy Marta Vila David Tabernero Josep Quer Ariadna Rando Rosa Lopez-Martinez Rafael Esteban Mar Riveiro-Barciela Maria Buti francisco rodríguez-Frías Liver Pathology Unit Departments of Biochemistry and MicrobiologyHospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Liver Unit Liver Disease Laboratory-Viral HepatitisVall d'Hebron Institut Recerca-Hospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Department of Microbiology Hospital Universitari Vall d'HebronUniversitat Autònoma de BarcelonaBarcelona 08035Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas Instituto de Salud Carlos ⅢMadrid 28029Spain Liver Unit Department of Internal MedicineHospital Universitari Vall d'HebronUniversitat Autónoma de BarcelonaBarcelona 08035Spain

BACKGROUND Since it is currently not possible to eradicate hepatitis B virus(HBV)infection with existing treatments,research continues to uncover new therapeutic *** core protein,encoded by the HBV core gene(HBC),intervenes in both structural and functional processes,and is a key protein in the HBV life *** this reason,both the protein and the gene could be valuable targets for new therapeutic and diagnostic ***,alterations in the protein sequence could serve as potential markers of disease *** To detect,by next-generation sequencing,HBC hyper-conserved regions that could potentially be prognostic factors and targets for new *** Thirty-eight of 45 patients with chronic HBV initially selected were included and grouped according to liver disease stage[chronic hepatitis B infection without liver damage(CHB,n=16),liver cirrhosis(LC,n=5),and hepatocellular carcinoma(HCC,n=17)].HBV DNA was extracted from patients’plasma.A region between nucleotide(nt)1863 and 2483,which includes HBC,was amplified and analyzed by next-generation sequencing(Illumina Mi Seq platform).Sequences were genotyped by distance-based discriminant *** and intergroup nt and amino acid(aa)conservation was determined by sliding window *** presence of nt insertion and deletions and/or aa substitutions in the different groups was determined by aligning the sequences with genotype-specific consensus *** Three nt(nt 1900-1929,2249-2284,2364-2398)and 2 aa(aa 117-120,159-167)hyper-conserved regions were shared by all the clinical *** groups showed a similar pattern of conservation,except for five nt regions(nt 1946-1992,2060-2095,2145-2175,2230-2250,2270-2293)and one aa region(aa 140-160),where CHB and LC,respectively,were less conserved(P<0.05).Some group-specific conserved regions were also observed at both nt(2306-2334 in CHB and 1935-1976 and 2402-2435 in LC)and aa(between aa 98-103 in CHB and 28-30 and 5

关键词： Hepatitis B virus Hepatitis B core gene Next-generation sequencing Genetic conservation Amino acid substitution Gene therapy Small interfering RNA

Characterization of hepatitis B virus X gene quasispecies complexity in mono-infection and hepatitis delta virus superinfection

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World Journal of Gastroenterology 2019年第13期25卷 1566-1579页

作者： Cristina Godoy David Tabernero Sara Sopena Josep Gregori Maria Francesca Cortese Carolina González Rosario Casillas Mar?al Yll Ariadna Rando Rosa López-Martínez Josep Quer Gloria González-Aseguinolaza Rafael Esteban Mar Riveiro-Barciela Maria Buti francisco rodríguez-Frías Liver Pathology Unit Departments of Biochemistry and Microbiology Hospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona Liver Unit Liver Disease Laboratory-Viral Hepatitis Vall d’Hebron Institut Recerca-Hospital Universitari Vall d'Hebron Universitat Autònoma de Barcelona Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) Instituto de Salud Carlos Ⅲ Roche Diagnostics SL Centro de Investigación Médica Aplicada (CIMA) Universidad de Navarra Liver Unit Department of Internal MedicineHospital Universitari Vall d’Hebron Universitat Autònoma de Barcelona (UAB)

Hepatitis delta virus(HDV) seems to strongly suppress hepatitis B virus(HBV)replication, although little is known about the mechanism of this interaction. Both these viruses show a dynamic distribution of mutants, resulting in viral quasispecies. Next-generation sequencing is a viable approach for analyzing the composition of these mutant spectra. As the regulatory hepatitis B X protein(HBx) is essential for HBV replication, determination of HBV X gene(HBX)quasispecies complexity in HBV/HDV infection compared to HBV monoinfection may provide information on the interactions between these two *** To compare HBV quasispecies complexity in the HBX 5' region between chronic hepatitis delta(CHD) and chronic HBV mono-infected *** Twenty-four untreated patients were included: 7/24(29.2%) with HBeAgnegative chronic HBV infection(CI, previously termed inactive carriers), 8/24(33.3%) with HBeAg-negative chronic hepatitis B(CHB) and 9/24(37.5%) with CHD. A serum sample from each patient was first tested for HBV DNA *** HBX 5' region [nucleotides(nt) 1255-1611] was then PCR-amplified for subsequent next-generation sequencing(MiSeq, Illumina, United States). HBV quasispecies complexity in the region analyzed was evaluated using incidencebased indices(number of haplotypes and number of mutations), abundancebased indices(Hill numbers of order 1 and 2), and functional indices(mutation frequency and nucleotide diversity). We also evaluated the pattern of nucleotide changes to investigate which of them could be the cause of the quasispecies *** CHB patients showed higher median HBV-DNA levels [5.4 logIU/mL,interquartile range(IQR) 3.5-7.9] than CHD(3.4 logIU/mL, IQR 3-7.6)(P = n.s.)or CI(3.2 logIU/mL, IQR 2.3-3.5)(P < 0.01) patients. The incidence and abundance indices indicated that HBV quasispecies complexity was significantly greater in CI than CHB. A similar trend was observed in CHD patients, although only Hill numbers of order 2 showed

关键词： Hepatitis B virus Hepatitis delta virus Hepatitis B X gene Next-generation sequencing Viral quasispecies Hepatitis B virus-hepatitis delta virus interaction

Genetic Diversity of the Endemic Xantus’ Hummingbird Using 16 Novel Polymorphic Microsatellite Loci, and Their Cross Amplification between Six Related Species

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Open Journal of Genetics 2016年第1期6卷 19-27页

作者： Cristina González-Rubio Sanvicente Ricardo rodríguez-Estrella Oscar Adrián Lozano-Garza francisco J. García-De-León Laboratorio de Genética para la Conservación Centro de Investigaciones Biológicas del Noroeste La Paz Mexico Laboratorio de Análisis Espacial Ecología y Conservación Centro de Investigaciones Biológicas del Noroeste La Paz Mexico

A set of 16 microsatellite loci was developed and characterized for the Xantus’ hummingbird (Hylocharis xantusii) by using 454 next-generation sequencing. Twenty-five H. xantusii samples from one population were genotyped;all loci were polymorphic, with the number of alleles ranging from three to ten. The mean observed heterozygosity was 0.681 for all loci. No significant linkage disequilibrium was detected, but five loci (Hxan05, 06, 09, 13 and 14) showed deviation from Hardy-Weinberg equilibrium. These microsatellite loci are the first to be characterized for H. xantusii. A moderate to high level of cross-species amplification was observed across the six hummingbird species (31% - 87.5%), with the best cross amplification results observed in the closest related species (H. leucotis, Cynanthus latirostris, Calypte costae). The availability of these molecular tools allows assessing questions integrating population genetics, ecology, conservation, and evolutionary history for H. xantusii and for other phyogenetically related species.

关键词： Baja California Peninsula Hylocharis xantusii Microsatellites Pyrosequencing Cross-Species Amplification

Preoperative calculation of angles of vision and working area in laparoscopic surgery to treat a giant hiatal hernia

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World Journal of Gastrointestinal Surgery 2021年第12期13卷 1638-1650页

作者： francisco Javier Perez Lara Rogelio Zubizarreta Jimenez francisco Javier Moya Donoso Jose Manuel Hernández Gonzalez Tatiana Prieto-Puga Arjona Arturo del Rey Moreno Maria Pitarch Martinez Surgery Service Antequera HospitalRincón de la Victoria 29730MálagaSpain DOXA Microfluidics Rincon de la Victoria 29738MálagaSpain

BACKGROUND Giant hiatal hernias still pose a major challenge to digestive surgeons,and their repair is sometimes a highly complex *** is usually performed by laparoscopy,while the role of the thoracoscopic approach has yet to be clearly *** To preoperatively detect patients with a giant hiatal hernia in whom it would not be safe to perform laparoscopic surgery and who,therefore,would be candidates for a thoracoscopic *** In the present study,using imaging test we preoperatively simulate the field of vision of the camera and the working area(instrumental access)that can be obtained in each patient when the laparoscopic approach is *** From data obtained,we can calculate the access angles that will be obtained in a preoperative computerised axial tomography coronal section,according to the location of the *** also provide the formula for performing the angle calculations If the trocars are placed in loss common situations,thus enabling us to determine the visibility and manoeuvrability for any position of the *** The working area determines the cases in which we can operate safely and those in which certain areas of the hernia cannot be accessed,which is when the thoracoscopic approach would be safer.

关键词： Hiatal hernia Angles Approach Laparoscopy Thoracoscopy

An approximate Kerr-Newman-like metric endowed with a magnetic dipole and mass quadrupole

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Communications in Theoretical Physics 2024年第8期76卷 124-138页

作者： francisco Frutos-Alfaro Space Research Center and School of Physics University of Costa RicaSan PedroSan JoseCosta Rica

Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely, mass, rotation, mass quadrupole, charge,and magnetic dipole moment. All these spacetimes approximately satisfy the Einstein-Maxwell field equations. The first metric is generated using the Hoenselaers-Perjés method from given relativistic multipoles. The second metric is a perturbation of the Kerr-Newman metric, which makes it a relevant approximation for astrophysical calculations. The last metric is an extension of the Hartle-Thorne metric that is important for obtaining internal models of compact objects perturbatively. The electromagnetic field is calculated using Cartan forms for locally non-rotating observers. These spacetimes are relevant for inferring properties of compact objects from astrophysical observations. Furthermore, the numerical implementations of these metrics are straightforward, making them versatile for simulating potential astrophysical applications.

关键词： Gravitation Einstein-Maxwell equations Compact objects

Validation of GIS layers in the EU:getting adapted to available reference data

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International Journal of Digital Earth 2011年第S1期4卷 42-57页

作者： francisco Javier Gallego IPSC Joint Research Centre of the ECIspraItaly

An optimal validation of a thematic map would ideally require in-situ observations of a large sample of units specifically conceived for the map under *** is often not possible due to budget *** alternative can be using photo-interpretation of high or very high resolution images instead of in-situ observations or using available data sets that do not fully comply with the ideal characteristics:unit size,reference date or sampling *** paper illustrates some examples of use of available data in the European *** land cover maps,the best existing data set is probably Land Use/Cover Areaframe Survey(LUCAS)that has been conducted by Eurostat on four occasions since *** LUCAS is based on systematic sampling,advantages and limitations of systematic sampling are discussed.A fine-scale population density map is presented as an example of a situation in which reference data on a statistical sample cannot be collected.

关键词： accuracy assessment area frame sampling systematic sampling LUCAS land cover maps population density

Translational pancreatic cancer research:a comparative study on patient-derived xenograft models

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World Journal of Gastroenterology 2018年第7期24卷 794-809页

作者： Mercedes Rubio-Manzanares Dorado Luis Miguel Marín Gómez Daniel Aparicio Sánchez Sheila Pereira Arenas Juan Manuel Praena-fernández Juan Jose Borrero Martín francisco Farfán López Miguel ángel Gómez Bravo Jordi Muntané Relat Javier Padillo Ruiz Department of Hepatobiliary and Pancreatic Surgery Virgen del Rocio University Hospital Oncology Surgery Cell Therapy and Organ Transplantation Group Institute of Biomedicine of Seville (IBiS) Virgen del Rocio University Hospital University of Seville Statistics Methodology and Evaluation of Research Unit Virgen del Rocio University Hospital Pathology Department Virgen del Rocio University Hospital

AIM To assess the viability of orthotopic and heterotopic patient-derived pancreatic cancer xenografts implanted into nude *** This study presents a prospective experimental analytical follow-up of the development of tumours in mice upon implantation of human pancreatic adenocarcinoma samples. Specimens were obtained surgically from patients with a pathological diagnosis of pancreatic adenocarcinoma. Tumour samples from pancreatic cancer patients were transplanted into nude mice in three different locations(intraperitoneal, subcutaneous and pancreatic). Histological analysis(haematoxylin-eosin and Masson's trichrome staining) and immunohistochemical assessment of apoptosis(TUNEL), proliferation(Ki-67), angiogenesis(CD31) and fibrogenesis(α-SMA) were performed. When a tumour xenograft reached the target size, it was reimplanted in a new nude mouse. Three sequential tumour xenograft generations were generated(F1, F2 and F3).RESULTS The overall tumour engraftment rate was 61.1%. The subcutaneous model was most effective in terms of tissue growth(69.9%), followed by intraperitoneal(57.6%) and pancreatic(55%) models. Tumour development was faster in the subcutaneous model(17.7 ± 2.6 wk) compared with the pancreatic(23.1 ± 2.3 wk) and intraperitoneal(25.0 ± 2.7 wk) models(P = 0.064). There was a progressive increase in the tumour engraftment rate over successive generations for all three models(F1 28.1% vs F2 71.4% vs F3 80.9%, P < 0.001). There were no significant differences in tumour xenograft differentiation and cell proliferation between human samples and the three experimental models among the sequential generations of tumour xenografts. However, a progressive decrease in fibrosis, fibrogenesis, tumour vascularisation and apoptosis was observed in the three experimental models compared with the human samples. All three pancreatic patient-derived xenograft models presented similar histological and immunohistochemical *** In our experie

关键词： Immunohistological analysis Pancreatic cancer Patient-derived xenograft Animal model Nude mice

Recycling of Glass Fibers from Fiberglass Polyester Waste Composite for the Manufacture of Glass-Ceramic Materials

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Journal of Environmental Protection 2012年第8期3卷 740-747页

作者： Felix Antonio López Maria Isabel Martín Irene García-Díaz Olga rodríguez francisco Jose Alguacil Maximina Romero Centro Nacional de Investigaciones Metalúrgicas (CENIM) CSIC Avda. Gregorio del Amo 8 28040 Madrid Spain Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC) Madrid Spain Instituto de Ciencias de la Construcción Eduardo Torroja (IETCC) CSIC Serrano Galvache 4 28033 Madrid Spain

This work presents the feasibility of reusing a glass fiber resulting from the thermolysis and gasification of waste composites to obtain glass-ceramic tiles. Polyester fiberglass (PFG) waste was treated at 550℃ for 3 h in a 9.6 dm3 thermolytic reactor. This process yielded an oil (≈24 wt%), a gas (≈8 wt%) and a solid residue (≈68 wt%). After the polymer has been removed, the solid residue is heated in air to oxidize residual char and remove surface contamination. The cleaning fibers were converted into glass-ceramic tile. A mixture consisting of 95 wt% of this solid residue and 5% Na2O was melted at 1450℃ to obtain a glass frit. Powder glass samples (<63 μm) was then sintered and crystallized at 1013℃, leading to the formation of wollastonite-plagioclase glass-ceramic materials for architectural applications. Thermal stability and crystallization mechanism have been studied by Differential Thermal Analysis. Mineralogy analyses of the glass-ceramic materials were carried out using X-ray Diffraction.

关键词： Valorisation Waste Composite Thermolysis Gasification Glass Fiber Glass-Ceramic