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High aluminum concentration and initial establishment of Handroanthus impetiginosus : clues about an Al non-resistant species in Brazilian cerrado

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Journal of Forestry Research 2020年第6期31卷 2075-2082页

作者： Ane marcela das chagas Mendon ca Jean Marcel Sousa Lira Ana Luiza de Oliveira Vilela Daniel Amorim Vieira Nayara cristina de Melo Joao Paulo Rodrigues Alves Delfi no Barbosa Programa de Pós-Graduacao em Fisiologia Vegetal Departamento de BiologiaUniversidade Federal de LavrasLavrasMG 37200-000Brazil Programa de Pós-Graduacao em ciências Ambientais Instituto de Ciências ExatasUniversidade Federal de AlfenasAlfenasMG 37130-001Brazil Programa de Pós-Graduacao em Fitotecnia Departamento de AgriculturaUniversidade Federal de LavrasLavrasMG 37200-000Brazil Instituto Federal de Educacao ciência e Tecnologia do Pará BelémPA 66093-020Brazil

cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmental *** investigated leaf nutritional status,and photosynthetic and growth characteristics during the initial establishment of Handroanthus impetiginosus(*** Dc.)Mattos,a secondary tree species distributed in the Brazilian *** goal was to understand leaf-level traits related to diff erent aluminum *** plants were cultivated in four diff erent aluminum sulfate concentrations:0,1,2,and 4 mM Al,for 40 *** performed analyses of growth,leaf gas exchange,chloroplast pigment content,and leaf mineral *** observed a linear increase of Al leaf content as a function of Al concentration in the nutrient *** grown in 1 mM Al showed a remarkable increase of K leaf content,net photosynthesis,stomatal conductance,and transpiration,while in 4 mM Al there were reductions of N,P,and K contents,gas exchange characteristics,and *** did not have mechanisms of avoidance,compartmentalization,or resistance to high Al ***,this species showed a hormetic response,with low Al concentrations stimulating and high Al concentrations inhibiting plant responses.

关键词： Hormesis Low Al concentration Al toxicity cerrado species carbon assimilation

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Diet switch and omega-3 hydroxy-fatty acids display differential hepatoprotective effects in an obesity/nonalcoholic fatty liver disease model in mice

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World Journal of Gastroenterology 2018年第4期24卷 461-474页

作者： Roberto Rodriguez-Echevarria Jose Macias-Barragan marcela Parra-Vargas Judith Rebeca Davila-Rodriguez Eduardo Amezcua-Galvez Juan Armendariz-Borunda Institute for Molecular Biology and Gene Therapy-cUcS Department of Molecular Biology and GenomicsUniversity of GuadalajaraGuadalajara 44340Mexico Department of Health Sciences-cUValles University of GuadalajaraGuadalajara 46600Mexico Hospital civil de Guadalajara Guadalajara 46600Mexico

AIM To study the effect of 18-hydroxy-eicosapentaenoic acid(18-HEPE) and 17-hydroxy-docosahexaenoic acid(17-HDHA) in a murine model of obesity/nonalcoholic fatty liver *** c57 BL/6 mice were fed with standard chow diet(cD) or high-fat, fructose-enriched diet(HFD) for 16 wk. Then, three groups were treated for 14 d with either, diet switch(HFD for cD), 18-HEPE, or 17-HDHA. Weightand fasting glucose were recorded on a weekly basis. Insulin tolerance test was performed at the end of treatment. Histological analysis(HE and Masson's trichrome stain) and determination of serum insulin, glucagon, glucagon-like peptide 1(GLP-1), glucose-dependent insulinotropic polypeptide, adiponectin and resistin were carried out as well as liver proteins by western *** Mice treated with hydroxy-fatty acids 18-HEPE and 17-HDHA displayed no weight loss or improved insulin sensitivity. However, these mice groups showed a significant amelioration on serum GLP-1, adiponectin and resistin levels. Also, a significant reduction on inflammatory infiltrate was observed at both portal and lobular zones. Furthermore, up-regulation of PPARα/γ protein levels was observed in liver tissue and it was associated with decreased levels of NF-κB also determined by western blot analysis. On the other hand, diet switch regimen resulted in a marked improvement in most parameters including: weight loss, increased insulin sensitivity, decreased steatosis, restored levels of insulin, glucagon, leptin, adiponectin and resistin. However, no significant changes were observed regarding inflammatory infiltrate in this last *** 18-HEPE and 17-HDHA differentially exert hepatoprotective effects through up-regulation of nuclear receptors PPARα/γ and amelioration of serum adipokines profile.

关键词： Nonalcoholic fatty liver disease Polyunsaturated fatty acids 18-hydroxy-eicosapentaenoic acid 17-hydroxy-docosahexaenoic acid Obesity

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Large-scale permafrost degradation as a primary factor in Larix sibirica forest dieback in the Khentii massif,northern Mongolia

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Journal of Forestry Research 2020年第1期31卷 197-208页

作者： David Juricka Jitka Novotna Jakub Houska Jana Parilkova Jan Hladky Vaclav Pecina Hana cihlarova marcela Burnog Jakub Elbl Zdena Rosicka Martin Brtnicky Jindrich Kynicky Department of Geology and Pedology Faculty of Forestry and Wood TechnologyMendel University in BrnoZemedelska 161300 BrnoCzech Republic central European Institute of Technology Brno University of TechnologyPurkynova 656/12361200 BrnoCzech Republic Institute of Water Structures Faculty of Civil EngineeringBrno University of TechnologyZizkova 1760200 BrnoCzech Republic

The objective of this study is to investigate the potential causes of widespread Larix sibirica *** observed in the Khentii massif of northern *** ratio of deadwood to living trees in affected stands in the Goricho region,the southernmost study site situated close to the Gobi Desert,was as high as 3.6:*** fluctuations monitored over 2 years using electrical impedance spectrometry revealed that the Goricho study site had higher soil moisture levels than the two less affected sites Barun Bayan and Dzun *** soil moisture was recorded in an area characterized by highly skeletal soils,ones with more than 35%by volume of rock fragments,and comparatively shallow soil horizons,from valley to *** layer of permafrost influencing hydrogeological processes is much deeper in the Goricho region compared to the undisturbed study *** analysis confirmed a significant number of dead *** on sites with developed *** forest stands,however damaged,grow in this region on well-drained scree slopes or on rocky *** mass mortality observed for *** may be directly linked to accelerated permafrost thaw in the area bordered by the Tuul and the Terelj *** assumption is that *** root system necrosis occurred as a result of long-term waterlogging of developed soils with high spatial heterogeneity,normally able to absorb high quantities of *** areas unaffected were scree fields and rocky bastions characterized by adequate *** of our findings support the primary stages of large-scale permafrost thaw,i.e.,correlating increases in soil moisture with increasing permafrost active layer thickness.

关键词： Larix sibirica Mortality Permafrost thawing Waterlogging Mongolia

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Effects of conservation Tillage on Total and Aggregated Soil Organic carbon in the Andes

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Open Journal of Soil Science 2013年第8期3卷 361-373页

作者： marcela Quintero Nicholas B. comerford Decision and Policy Analysis Research Area International Center for Tropical Agriculture (CIAT) Cali Colombia University of Florida North Florida Research and Education center University of Florida (UF) Quincy USA University of Florida North Florida Research and Education center University of Florida (UF) Quincy USA

Many Andisols of the Andes have been disturbed by traditional potato-based rotation agriculture disrupting soil structure, water retention capacity and organic matter content. This study was undertaken to investigate the contribution of conservation farming technology or reduced tillage in potato-based rotations in the colombian Andes in order to rehabilitate total and aggregated soil organic c in disturbed organic matter-rich Andisols. Soils were sampled from farms with 7-year of reduced tillage and farms with conventional farming practices. Ultrasound energy was applied to samples to disrupt aggregation and total soil c was determined in order to investigate the amount of carbon held inside the aggregates of different soil size classes. Results indicated that reduced tillage in potato-based crop rotations increased the soil c concentration and average c content in the whole profile (≈117 cm depth) by 50 and 33% (1636 t c ha?1 vs. 1224 t c ha?1), respectively, as compared to conventional farming practices. carbon content increased 177% in the subsoil (A2 horizon, 78 -117 cm depth, from 215 to 596 t?ha?1), although most of the soil c was in the A1 horizon (between 0 -78 cm average thickness, 1097 t?ha?1). These increases show that reduced tillage enhances c stores in Andisols which are already high in organic matter. In addition, c in aggregates represented more than 80% of the total organic matter and it was positively affected by conservation practices. The c increase was preferential in the smaller macroaggregates (

关键词： conservation Tillage Soil Organic carbon Soil Aggregates Andes Potato

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Blood pressure and stature in Helicobacter pylori positive and negative persons

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World Journal of Gastroenterology 2014年第19期20卷 5625-5631页

作者： marcela Kopacova Ilona Koupil Bohumil Seifert Miluska Skodova Fendrichova Jana Spirkova Viktor Vorisek Stanislav Rejchrt Tomas Douda Ilja Tacheci Jan Bures 2~(nd)Department of Internal Medicine-Gastroenterology Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital50005 Hradec KraloveCzech Republic centre for Health Equity Studies Stockholm UniversityKarolinska Institute17177 StockholmSweden Institute of General Practice First Faculty of MedicineCharles University12002 PrahaCzech Republic Institute of clinical Biochemistry and Diagnostics Charles University in PrahaFaculty of Medicine at Hradec KraloveUniversity Teaching Hospital50005 Hradec KraloveCzech Republic

To evaluate vital signs and body indices in Helicobacter pylori (H. pylori) positive and negative persons. A total of 22 centres entered the study. They were spread over the whole country, corresponding well to the geographical distribution of the czech population. A total of 1818 subjects (aged 5-98 years) took part in the study, randomly selected out of 38147 subjects. H. pylori infection was investigated by means of a 13c-urea breath test. Data on height, weight, systolic and diastolic blood pressure and heart rate were collected at the clinics of general practitioners. The overall prevalence of H. pylori infection was 30.4% (402/1321) in adults (≥ 18 year-old) and 5.2% (26/497) in children and adolescents (≤ 17 year-old). Once adjusted for age and gender, only a difference in body mass index remained statistically significant with H. pylori positive adults showing an increase of 0.6 kg/m2 in body mass index. Once adjusted for age and gender, we found a difference in height between H. pylori positive and H. pylori negative children and adolescents. On further adjustment for place of residence, this difference became statistically significant, with H. pylori positive children and adolescents being on average 3.5 cm shorter. H. pylori positive adults were significantly older compared to H. pylori negative subjects. Once adjusted for age and gender, H. pylori infection had no impact on body weight, body mass index and vital signs either in adults or children and adolescents. chronic H. pylori infection appeared to be associated with short stature in children. H. pylori infection did not influence blood pressure, body weight and body mass index either in adults or children and adolescents.

关键词： Epidemiology Helicobacter pylori czech Republic 13c-urea breath test Blood pressure Heart rate Weight Stature Body mass index

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Ibuprofen-Maltodextrin Interaction: Study of Enantiomeric Recognition and complex characterization

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Pharmacology & Pharmacy 2013年第1期4卷 18-30页

作者： claudia Garnero carolina Aloisio marcela Longhi Departamento de Farmacia Facultad de Ciencias Químicas Universidad Nacional de Córdoba Ciudad Universitaria Córdoba Argentina

The interaction between ibuprofen and maltodextrins with different dextrose equivalent was studied in solution and solid state in order to investigate the effect on the solubility of ibuprofen and to determine their usefulness in terms of chiral recognition. Apparent binding constants were calculated using nuclear magnetic resonance spectroscopy experiments and solubility studies. The results showed an increase in the apparent solubility of ibuprofen in the presence of maltodextrins that depended on their ionization state. The freeze-drying method was used to prepare solid complexes, while physical mixtures were obtained by simple blending. These solid systems were characterized in the solid state using differential scanning calorimetry, thermogravimetric analysis, Fourier Transform-Infrared spectroscopy, scanning electron microscopy and X-ray diffractometry. Detailed nuclear magnetic resonance studies provided evidence of the influence of the type and concentration of the maltodextrin host on the chiral recognition of racemic ibuprofen, indicating that these linear ligands act as chiral selectors.

关键词： Ibuprofen Maltodextrin chiral Recognition complex characterization Nuclear Magnetic Resonance Spectroscopy Solubility Studies

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An Experimental Study of Self-compacting concrete Made with Filler from construction and Demolition Waste

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Open Journal of civil Engineering 2020年第4期10卷 364-384页

作者： Mônica Batista Leite marcela crusoé Figueiredo civil and Environmental Engineering Graduate Program Department of Technology State University of Feira de Santana Feira de Santana Brazil UNIFAcS Feira de Santana Brazil

This study evaluated the influence of the Portland cement replacement by 0, 5%, 10%, 15% and 20% of construction and Demolition Waste (cDW) filler contents in the production of self-compacting concrete (Scc). The Scc ... 详细信息

This study evaluated the influence of the Portland cement replacement by 0, 5%, 10%, 15% and 20% of Construction and Demolition Waste (CDW) filler contents in the production of self-compacting concrete (SCC). The SCC mixtures were evaluated on fresh state by slump flow, J-ring, resistance of segregation, specific gravity, and on hardened state by compressive and splitting tensile strength, specific gravity, air voids and absorption rate. The results indicated that all Scc produced with cDW filler met the limits established at any level of substitution without changes of the w/c ratio or superplasticizer content. It was possible to verify that the presence of cDW filler, in substitution of cement, by volume, improves the resistance to segregation and up to 5% of cDW filler decreases the loss of fluidity with time as compared to reference. It was found that all Scc mixtures, at 28 days, had the average compressive strength above 50 MPa, without showing significant loss with up to 20% of cDW filler. For splitting tensile strength, Scc recycled mixtures reached up to 92.5% of the Scc used as referenc

关键词： Self-compacting concrete construction and Demolition Waste Filler Mineral Admixtures Slump Flow

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What can natural edges of gallery forests teach us about woody community performance in sharp ecotones?

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Journal of Plant Ecology 2017年第6期10卷 937-948页

作者： Gabriela Aparecida de Oliveira coelho marcela de castro Nunes Santos Terra Hisaias de Souza Almeida Eduardo van den Berg Departamento de ciências Florestais Universidade Federal de LavrasC.Postal 3037LavrasMG 37200-000Brazil Instituto de Recursos Naturais Universidade Federal de ItajubáC.Postal 50ItajubáMG 37500-903Brazil Departamento de Biologia Universidade Federal de LavrasC.Postal 3037LavrasMG 37200-000Brazil

Aims The diversity and structure of forest edges are a central issue in ***,most studies have focused on anthropogenic for-est edges,being natural ones least *** studied the com-munities of shrubs and trees in natural edges of gallery forests with the main goal of learning what are the main factors that shape the structure and diversity of these natural sharp *** We evaluated 10 gallery forest sites,allocating in each of them three 15×20 m *** plots were laid out in relatively rectilinear stretches of forest edges,respecting a minimal distance of 10 m between each *** they are permanent plots and meant to study eventual fluctuations in the forest-grasslands limits,we allocated the plots with their longest side parallel to the forest edge and covering perpendicularly 5 m of the grassland and 10 m of *** the plots we identified,mapped and measured all shrub and tree individuals with diameter at breast height(DBH)≥1 *** Findings Although many differences exist among the communities in terms of density and basal area,all of them were highly dense and had relatively low basal *** addition,both the number of individu-als and the basal area increased rapidly towards the forest *** results also revealed that the edge communities are composed mainly by small individuals that demand a great amount of *** the vertical stratification and the proportion of the functional groups are similar among the sites yet change quickly in the first 10 m of the forest ***,the floristic similarities were low among the communities mainly due to the species turnover within each ***,although the overall structure is constant in the studied edges,the low floristic similarity among them possibly indicates that the species within the same functional groups are sub-stituting each other across the *** older and seemingly stable,our results showed the gallery forest edges are quite simila

关键词： beta diversity edge effects ecotone forest-grassland transition functional groups.

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Multi-temporal NDVI analysis using UAV images of tree crowns in a northern Mexican pine-oak forest

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林业研究:英文版 2023年第6期34卷 1855-1867页

作者： JoséLuis Gallardo-Salazar marcela Rosas-chavoya Marín Pompa-García Pablito Marcelo López-Serrano Emily García-Montiel Arnulfo Meléndez-Soto Sergio Iván Jiménez-Jiménez Instituto de Investigaciones Agropecuarias y Forestales Universidad Michoacana de San Nicolás de Hidalgo(UMSNH)58330 MoreliaMichoacánMexico Programa Institucional de Doctorado en ciencias Agropecuarias y Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Facultad de ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.DurangoValle del Sur s/n34120 DurangoDurangoMéxico Instituto de Silvicultura e Industria de la Madera Universidad Juárez del Estado de DurangoBoulevard del Guadiana 501Ciudad UniversitariaTorre de Investigación34120 DurangoMéxico INIFAP-cENID RASPA centro Nacional de Investigación Disciplinaria en Relación Agua-Suelo-Planta-Atmósfera Margen derecha canal Sacramento km 6.5Zona industrial35140 Gómez PalacioDurangoMexico

The use of unmanned aerial vehicles(UAV)for forest monitoring has grown significantly in recent years,providing information with high spatial resolution and temporal *** with multispectral sensors allow the use of indexes such as the normalized difference vegetation index(NDVI),which determines the vigor,physiological stress and photo synthetic activity of *** study aimed to analyze the spectral responses and variations of NDVI in tree crowns,as well as their correlation with climatic factors over the course of one *** study area encompassed a 1.6-ha site in Durango,Mexico,where Pinus cembroides,Pinus engelmannii,and Quercus grisea *** images were acquired with UAV and information on meteorological variables was obtained from NASA/POWER *** ANOVA explored possible differences in NDVI among the three *** correlation was performed to identify the linear relationship between NDVI and meteorological *** differences in NDVI values were found at the genus level(Pinus and Quercus),possibly related to the physiological features of the species and their *** grisea had the lowest NDVI values throughout the year which may be attributed to its sensitivity to relative humidity and *** the use of UAV with a multispectral sensor for NDVI monitoring allowed genera differentiation,in more complex forest analyses hyperspectral and LiDAR sensors should be integrated,as well other vegetation indexes be considered.

关键词： Multispectral images Normalized diff erence Vegetation index Phenology Unmanned aerial vehicles Multitemporal analysis

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critical Nitrogen Dilution curve in Processing Potato cultivars

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American Journal of Plant Sciences 2015年第19期6卷 3144-3156页

作者： claudia marcela Giletto Hernán Eduardo Echeverría Unidad Integrada FcA UNMdP-INTA Balcarce Argentina

The critical nitrogen dilution curve (cNDc) can be used as a diagnostic tool to assess crop N nutrition during the growing season. Potato cultivars have different biomass production and accumulation of N and consequently different growth patterns. These differences among cultivars may result in different cNDc. The aims were a) to determine the cNDc for different potato cultivars;b) to compare these curves with reference curves;and c) to assess the possibility of using the cNDc to estimate the N nutritional status of the crop. The biomass production and N concentration of shoots and tubers of potato cultivars Innovator, Gem Russet, Umatilla Russet, Bannock Russet and Markies Russet were measured. The harvest index (HI) and N harvest index (NHI) were determined. The coefficient a of the cNDc was similar among cultivars, while the coefficients b for Innovator and Gem Russet (-0.42 and -0.36, respectively) were smaller than those for the other cultivars (average -0.25). HI and NHI were greater in Innovator, smaller in Markies Russet, and intermediated in the other three cultivars. The coefficients b of the cNDc were correlated with HI and NHI (HI, r = -0.62, p ctively). The relationship between relative tuber yield (RY) and N nutrition index (NNI) was fit by a quadratic-plateau function. At similar situations of N deficiency, Innovator had lower yield and greater response to N rate than the other potato cultivars. The differences in HI and NHI among cultivars may explain the differences in the coefficient b of the cNDc. The NNI identified the status of N adequately in potato cultivars.

关键词： Harvest Index N Harvest Index coefficient of Dilution Processing Potato

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