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Micromorphology of Surface Crusts in the Knersvlakte,South Africa

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Journal of Mountain Science 2009年第2期6卷 189-196页

作者： Sarah-Jane C.Fox Anthony J.Mills Rosa M.Poch Department of Soil Science Stellenbosch UniversityStellenbosch South Africa Department of Environment and Soil Science University of LleidaRovira Roure 191 Lleida

Soils in the Knersvlakte are particularly prone to crusting and have lower inherent infiltrability than other soils across western southern Africa. Micromorphological techniques were used to examine the structure and porosity of soil crusts in the Knersvlakte to ascertain why crusting is so intense in this region. Quantile regression using boundary lines was employed to examine the relationships between infiltrability and soil properties for all samples (n = 67). This analysis showed that infiltrability is potentially maximal at low water-dispersible 'clay plus silt' content and low silt content (r2 = 0.72 and 0.64; respectively, n = 67) (Figure 2). The strength of crusts, pH, EC, clay mineralogy, and water-dispersible clay, silt and 'clay plus silt' content were compared, and a pore analysis using optical microscopy was undertaken on images of six soil thin sections (n = 6) (circular and parallel polarizers). Pore analysis was further undertaken on five horizontal slices of equal dimensions taken through each soil thin section. The porosity samples with low infiltrability ( 100 mm·hr-1, n = 2). The porosity samples with low infiltrability showed a trend of lower pH and greater water dispersible clay percentage. Porosity varied within the porosity samples due to the presence of dense clay/silt bands (< 0.5 mm in width) with relatively few air vesicles. The porosity samples with horizontal slices of low porosity (but large numbers of air vesicles) had low infiltrability, while those without slices of low porosity (and relatively few air vesicles) had high infiltrability. We conclude that the intense crusting and resultant low infiltrability of soils in the Knersvlakte appears to be related to the formation of thin, dense clay/silt bands in the pedoderm.

关键词：微观表面低孔隙度土壤特性分散粘土硬壳南非低pH值分位数回归

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling appr

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

Cell senescence,loss of splicing,and lipid metabolism in TDP-43-related neurodegenerative processes

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Neural Regeneration Research 2023年第8期18卷 1725-1726页

作者： Pascual Torres Reinald Pamplona Manuel Portero-Otin Metabolic Pathophysiology Research Group Department of Experimental MedicineUniversity of Lleida-IRBLleidaLleidaSpain

In recent work,we have shown that cell senescence of mouse fibroblasts in vitro associates with a build-up of cryptic exons in selected mRNAs,whose level is usually controlled by the activity of TAR DNA binding protein of 43 kDa(Tdp-43)(Torres et al.,2022).In vivo,we also found traits of cell senescence in the motor neuron disease model achieved by overexpressing SOD-G93A,the SOD1 gene(harboring a single amino acid substitution of glycine to alanine at codon 93).

关键词： metabolism degenerative

Transient and DNA-free in vivo CRISPR/Cas9 genome editing for flexible modeling of endometrial carcinogenesis

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Cancer Communications 2023年第5期43卷 620-624页

作者： Raúl Navaridas Maria Vidal-Sabanés Anna Ruiz-Mitjana Aida Perramon-Güell Cristina Megino-Luque David Llobet-Navas Xavier Matias-Guiu Joaquim Egea Mario Encinas Lídia Bardia Julien Colombelli Xavier Dolcet Oncological Pathology Group Department of Basic Medical SciencesUniversity of LleidaBiomedical Research Institute of LleidaLleidaSpain Molecular Mechanisms and Experimental Therapy in Oncology-Oncobell Program Bellvitge Biomedical Research Institute’L’Hospitalet de LlobregatBarcelonaSpain Department of Pathology Bellvitge HospitalUniversity of BarcelonaBellvitge Biomedical Research InstituteL’Hospitalet de LlobregatBarcelonaSpain Department of Pathology Arnau de Vilanova HospitalUniversity of LleidaBiomedical Research Institute of LleidaLleidaSpain Cancer Networking Biomedical Research Center Institute of Health Carlos IIIMadridSpain Molecular Developmental Neurobiology Group Department of Basic Medical SciencesUniversity of LleidaBiomedical Research Institute of LleidaLleidaSpain Developmental and Oncogenic Signalling Group Department of ExperimentalMedicineUniversity of LleidaBiomedical Research Institute of LleidaLleidaSpain Advanced Digital Microscopy Core Facility Institute for Research in BiomedicineBarcelona Institute of Science and TechnologyBarcelonaSpain

Dear Editor,The Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)and CRISPR-associated protein 9(Cas9)(CRISPR/Cas9)-mediated generation of somatically genetically engineered mouse models have emerged as a new approach for in vivo modeling of cancer[1].Here,we describe a novel DNA-free,easy,rapid,flexible,multiplexable,and robust method to model endometrial neoplasia by CRISPR/Cas9 ribonucleoprotein(RNP)electroporation into the uterus of mice.

关键词： CRISPR/Cas9 DNA CRISPR

Declining metabolic scaling parallels an ontogenetic change from elongate to deep-bodied shapes in juvenile Brown trout

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Current Zoology 2023年第3期69卷 294-303页

作者： Jorge-Ruben Sanchez-Gonzalez Alfredo G.Nicieza Department of Organisms andSystems Biology University of Oviedo33006O OviedoSpain Biodiversity Research Institute(IMIB) University of Oviedo-Principality of Asturias-CSIC33600 MieresSpain Department of Animal Science-Wildlife Section University of Lleida25006 LleidaSpain

Body shape and metabolic rate can be important determinants of animal performance,yet often their effects on influential traits are evaluated in a non-integrated way.This creates an important gap because the integration between shape and metabolism may be crucial to evaluate metabolic scaling theories.Here,we measured standard metabolic rate in 1-and 2-years old juvenile brown trout Salmo trutta,and used a geometric morphometrics approach to extricate the effects of ontogeny and size on the link between shape and metabolic scaling.We evidenced near-isometric ontogenetic scaling of metabolic rate with size,but also a biphasic pattern driven by a significant change in metabolic scaling,from positive to negative allometry.Moreover,the change in metabolic allometry parallels an ontogenetic change from elongate to deep-bodied shapes.This is consistent with the dynamic energy budget(DEB)and surface area(SA)theories,but not with the resource transport network theory which predicts increasing allometric exponents for trends towards more robust,three-dimensional bodies.In addition,we found a relationship between body shape and size independent metabolic rate,with a positive correlation between robustness and metabolic rate,which fits well within the view of Pace-of-Life Syndromes(POLS).Finally,our results align with previous studies that question the universality of metabolic scaling exponents and propose other mechanistic models explaining the diversity of metabolic scaling relationships or emphasizing the potential contribution of ecological factors.

关键词： biphasic allometric scaling metabolic rate ontogenetic allometry shape surface-area trout

The relationship between fire severity and burning efficiency for estimating wildfire emissions in Mediterranean forests

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林业研究:英文版 2023年第5期34卷 1195-1206页

作者： Bountouraby Balde Cristina Vega-Garcia Pere Joan Gelabert Aitor Ameztegui Marcos Rodrigues Department of Agriculture and Forest Engineering University of LleidaAv.Alcalde Rovira Roure19125198 LleidaSpain Department of Geography and Land Management University of ZaragozaPedro Cerbuna 1250009 SaragossaSpain

Forests are exposed to changing climatic conditions reflected by increasing drought and heat waves that increase the risk of wildfire ignition and spread.Climatic variables such as rain and wind as well as vegetation structure,land configuration and forest management practices are all factors that determine the burning potential of wildfires.The assessment of emissions released by vegetation combustion is essential for determining greenhouse gases and air pollutants.The estimation of wildfire-related emissions depends on factors such as the type and fraction of fuel(i.e.,live biomass,ground litter,dead wood)consumed by the fire in a given area,termed the burning efficiency.Most approaches estimate live burning efficiency from optical remote sensing data.This study used a data-driven method to estimate live burning efficiency in a Mediterranean area.Burning severity estimations from Lands at imagery(dNBR),which relate to fuel consumption,and quantitative field data from three national forest inventory data were combined to establish the relationship between burning severity and live burning efficiency.Several proxies explored these relationships based on dNBR interval classes,as well as regres sion models.The correlation results between live burning efficiency and dNBR for conifers(R=0.63)and broad-leaved vegetation(R=0.95)indicated ways for improving emissions estimations.Median estimations by severity class(low,moderate-low,moderate-high,and high)are provided for conifers(0.44-0.81)and broad-leaves(0.64-0.86),and regression models for the live fraction of the tree canopy susceptible to burning(7 branches,and leaves).The live burning efficiency values by severity class were higher than previous studies.

关键词： Forest wildfires Emissions Greenhouse gases Satellite images

Ocular surface squamous neoplasia resistant to topical interferon alpha 2b in a patient with follicular lymphoma

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International Journal of Ophthalmology(English edition) 2021年第7期14卷 1122-1124页

作者： Valentin Huerva Magi Vilaltella Department of Ophthalmology University Hospital Arnau de VilanovaLleida 25198Spain School of Medicine University of Lleida(UdL)Lleida 25198Spain Biomedical Research Institute of lleida(IRB) Lleida 25198Spain

Dear Editor,Treatment for ocular surface squamous neoplasia(OSSN)includes topical mitomycin C(MMC),5-fluorouracil(5-FU)and interferon(IFN)-alpha 2b eyedrops[1-2].Compared to other treatments,such as mitomycin C(MMC),I... 详细信息

关键词： interferon squamous neoplasia

Organic practices and gender are effective strategies to provide healthy pork loin

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Journal of Integrative Agriculture 2016年第3期15卷 608-617页

作者： Javier Alvarez-Rodríguez Daniel Villalba Dolors Cubiló Daniel Babot Marc Tor Animal Science Department University of Lleida-Agrotecnio Center Lleida 25198 Spain

This study evaluated the influence of husbandry（organic feed and management but not free-ranging vs. conventional） and sex（barrows vs. gilts） on pork meat quality. A total of 60 Longissimus thoracis pork muscle samples from different 3-way crossbred genotypes were chosen from 3 conventional and 2 organic pig farms. Technological meat quality was measured at 24 h post-mortem and muscle fatty acid content and composition was analysed by gas chromatography. The loin from organic pigs at 24 h of retail display had lower pH, but it had no detrimental effects on drip loss. All the International Commission on Illumination colour attributes except meat lightness differed between husbandry systems. Moisture and crude protein content were lower whereas intramuscular fat content was greater in organic than in conventional pork. Total saturated fatty acid（SFA）, monounsaturated fatty acid（MUFA）, polyunsaturated fatty acid（PUFA） and PUFA n-6 contents did not differ between husbandry systems, but total PUFA n-3（mainly C18：3 n-3） were greater in organic than in conventional pork. Sex did not affect ultimate p H or meat colour attributes but barrows showed lower moisture and greater intramuscular fat than gilts. Total SFA and MUFA content were similar but all the PUFA（both n-6 and n-3） were lower in barrows than in gilts. These results suggest that some bioactive compounds from dietary origin, i.e., linolenic acid（C18：3 n-3） content from dietary vegetable oils（soybean or olive olein）, might be used to highlight the nutritive value of（not free-ranging） organic pork meat. In addition, gilts were leaner than barrows and showed a more favourable PUFA/SFA ratio.

关键词： Longissimus muscle chemical composition intramuscular fat fatty acids pigs

Soil mineral nitrogen dynamics in fallow periods in a rainfed semiarid Mediterranean agricultural system

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Pedosphere 2023年第4期33卷 622-637页

作者： Awais SHAKOOR Àngela D.BOSCH-SERRA Antonio LIDON Damián GINESTAR Jaime BOIXADERA university of lleida Department of Environment and Soil SciencesAvda.Alcalde Rovira Roure 191Lleida E-25198(Spain) Institute of Water and Environmental Engineering Universitat Politècnica de ValènciaCamino de Vera s/n.Valencia E-46022(Spain) Institute for Multidisciplinary Mathematics Universitat Politècnica de ValènciaCamino de Vera s/n.Valencia E-46022(Spain) Department of Agriculture LivestockFisheries and FoodGovernment of CataloniaAvda.Alcalde Rovira Roure 191Lleida E-25198(Spain)

Rainfed agricultural systems in semiarid Mediterranean environments are subject to erratic but often heavy rainfall events.As an agronomic practice,fallow periods can be included even within the existing European Union common policy for crop diversification.This study aimed to quantify the effects of previous mineral fertilization on soil mineral nitrogen(N_(min))content and potential nitrate leaching during no-till fallow periods of crop rotation.The Leaching Estimation and Chemistry Model(LEACHM)was used for soil N_(min)prediction after fallow.During fallow periods,N_(min)measured in the soil profile increased by an average of 125 kg N ha^(-1),whereas the model showed an average increase of 95 kg N ha^(-1).The amount of nitrogen(N)leached was estimated to be 11–38 kg N ha^(-1).The N balance simulated using LEACHM might differ from the actual situation.The calibrated LEACHM underestimated soil N_(min)after a drought period followed by soil water replenishment,probably due to a pulse in soil C and N mineralization caused by the wetting of dry soil,but overestimated soil N_(min)after occasional rainy spells when soil quickly became saturated,probably due to occasional nitrous oxide emissions not being fully accounted for by the model and specific preferential water flow,which might lead to greater nitrate leaching than that simulated by LEACHM using the convection-dispersion equation.The results show that soil N_(min)measurements after fallow periods cannot be well predicted by LEACHM.The findings of this study provide a support for fertilization planning for crop rotation systems including a fallow period to avoid overfertilization in the following cropping season and reduce N environmental impacts.

关键词： crop rotation Latin Hypercube-One factor at a Time(LH-OAT)method Leaching Estimation and Chemistry Model(LEACHM) mineral fertilizer nitrogen balance nitrogen environmental impacts nitrogen leaching soil water