Persistence and intensity of soil water repellency from soils with andic properties from the Campania region (Southwest, Italy) under different forest types

Congreso celebrado del 2-6, julio, 2012, en Fiera del Levante, Bari, Italia.Soil water repellency (SWR) is a property of many soils that is getting more and more interesting for the scientific community, because of its consequences on soil erosion risk, runoff or infiltration rates and even plant ecology. The presence of hydrophobic organic acids released by roots and plant tissues, fungal activity, organic matter mineralization rates, or wildfires are considered the main causes of SWR. Some of the consequences of SWR are reduced soil infiltration rates, enhanced runoff flow and soil erosion. Significance of these effects depends upon the severity and spatial variability of SWR. SWR is often associated to vegetation types, although it cannot be assumed that certain species always induce water repellency under natural conditions. Because of resins, waxes and aromatic oils in their tissues, evergreen trees as eucalyptus and coniferous are usually associated with soil hydrophobicity, although it has been found also in a variety of soils, climates and vegetation types. But the relationship between water repellent soils and plant species is not always one-to-one. Soil properties as texture, aggregation, acidity, microbiome and other are also implied in the development of hydrophobicity. Regarding organic matter, several authors have reported inconsistent results after studying the relationship between soil organic matter content and SWR. A possible explanation for this is that quality of organic matter is more important than content. Consequently, it is necessary to investigate the role that organic matter content and properties play in the development of hydrophobicity in different soil and vegetation types. The objective of this research is the study the relationship between SWR and organic matter properties in andic soils from the Campania region (SW Italy) under different vegetation types.Peer reviewe

A 3-D indoor analysis of path loss modeling using kriging techniques

This study proposes a novel measurement-based method to predict and model three-dimensional (3-D) path loss in indoor scenarios, which first regresses 28 GHz measurements via median path loss modeling and then includes ordinary Kriging to interpolate shadowing. The performance of this method is evaluated by investigating the spatial structure that follows shadowing through the semivariogram, covariance function, and correlogram as variography tools. It is shown that semivariogram outperforms the other statistics to describe shadowing spatial continuity in path loss modeling in terms of the mean absolute error.This work was supported by the National Council of Science and Technology CONACYT, through the student scholarship number 746015, under Project RTI2018-095499-B-C31, funded by the Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER, UE)

Composition and Antidiarrheal Activity of Bidens odorata

The antidiarrheal effects of chloroform, methanol, and aqueous extracts of Bidens odorata Cav. were investigated at doses of 200 mg/kg on castor-oil-induced diarrhea. The chloroform extract of B. odorata (CBO) reduced diarrhea by 72.72%. The effect of CBO was evaluated on mice with diarrhea induced by castor oil, MgSO4, arachidonic acid, or prostaglandin E2. CBO inhibited the contraction induced by carbachol chloride on ileum (100 µg/mL) and intestinal transit (200 mg/kg) in Wistar rats. The active fraction of CBO (F4) at doses of 100 mg/kg inhibited the diarrhea induced by castor oil (90.1%) or arachidonic acid (72.9%) but did not inhibit the diarrhea induced by PGE2. The active fraction of F4 (FR5) only was tested on diarrhea induced with castor oil and inhibited this diarrhea by 92.1%. The compositions of F4 and FR5 were determined by GC-MS, and oleic, palmitic, linoleic, and stearic acids were found. F4 and a mixture of the four fatty acids inhibited diarrhea at doses of 100 mg/kg (90.1% and 70.6%, resp.). The results of this study show that B. odorata has antidiarrheal effects, as is claimed by folk medicine, and could possibly be used for the production of a phytomedicine

Genetic characterization by amplified fragment length polymorphism (AFLP) markers and morphochemical traits of Carica papaya L. genotypes

Carica papaya L. is a native fruit from Central America and Mexico and it is an economically important fruit. As a pre-breeding genetic study, the variability of both parents (L7 and M22) and the F1 individuals derived from their crosses (L7 × M22), was evaluated in terms of 32 morphochemical traits, and contrasted with their genetic diversity indicated by amplified fragment length polymorphism (AFLP) markers. According to morphochemical traits, L7 and M22 were grouped in two different clades. The first group included L7 and 13 genotypes from the F1, while a second group included the parent M22 and 15 other genotypes from the F1 progeny. The analysis based on morphochemical traits showed an average correlation of 0.652 among genotypes. For AFLP analysis the combination of the primers E-ACA/M-CTA had the best polymorphic index (72.73%). When they were grouped based on AFLPs markers, it was confirmed that both parents are genetically distant, and they were again grouped in two different clades. Five genotypes from the F1 population were grouped in the same clade as L7 and shared 55% similarity. Twenty six genotypes were grouped in the same clade as M22, showing 63.3% similarity. Another 12 genotypes (mainly female genotypes) were grouped in a third independent clade. This relative general agreement between the grouping based on a large number of morphochemical traits (including both plant and fruit traits) and that based on its genetic diversity using AFLPs, suggests that morphochemical characterization, together with genetic analysis by AFLPs, can be complementary and useful techniques for the identification and assessment of genetic diversity within C. papaya L. genotypes, that should be useful for genetic breeding programs of this important species.Key words: Morphological markers, AFLP markers, genetic similarity, Carica papaya L

‘Candidatus Rickettsia asemboensis’ and Wolbachia spp. in Ctenocephalides felis and Pulex irritans fleas removed from dogs in Ecuador

Abstract\ud \ud Background\ud Flea-borne infections are distributed worldwide. Up to date there are no reports about microorganisms associated to fleas in Ecuador.\ud \ud \ud Methods\ud Seventy-one Pulex irritans and 8 Ctenocephalides felis fleas were removed from dogs in two Ecuadorian areas (Pastaza and Chimborazo Provinces) in December 2012. DNA extracts were tested by polymerase chain reaction (PCR) assays targeting universal 16S rRNA, as well as screened for the presence of Rickettsia spp. (gltA, htrA, ompB, sca4 and ompA genes) and Bartonella spp. (rpoB, gltA and ITS genes).\ud \ud \ud Results\ud Our results showed the presence of ‘Candidatus Rickettsia asemboensis’ (highly similar to R. felis) in C. felis and Wolbachia spp. endosimbionts in P. irritans collected from animals in Ecuador. No fleas were found to be positive for any Bartonella species or Yersinia pestis.\ud \ud \ud Conclusions\ud Clinicians should be aware of the potential risk of this new Candidatus Rickettsia sp. and keep in mind other flea-borne infections since these flea species frequently bite humans

Adaptable Ultraviolet Refl ecting Polymeric Multilayer Coatings of High Refractive Index Contrast

A synthetic route is demonstrated to build purely polymeric nanostructured multilayer coatings, adaptable to arbitrary surfaces, and capable of effi ciently blocking by refl ection a targeted and tunable ultraviolet (UV) range. Refl ection properties are determined by optical interference between UV light beams refl ected at the interfaces between polystyrene layers of different porosity and hence refractive index. As no dopant absorber intervenes in the shielding effect, polymer degradation effects are prevented. Alternated porosity results from the modulation of photochemical effects at the few tens of nanometers length scale, combined with the collective osmotic shock induced during the processing of the precursor diblock copolymer fi lm. Experimental evidence of the application of this method to coat rough surfaces with smooth and conformal UV protecting fi lms is providedEuropean Union’s Seventh Framework Programme 307081Ministerio de Economía y Competitividad MAT2011-2359

Extracción y purificación de timol y carvacol en orégano (Lippia graveolens Kunth) para su evaluación biológica sobre semillas de maíz cebú (Zea mays L.) y sorgo (Sorghum bicolor L. Moench) como fitorregulador natural.

México es el principal exportador a nivel mundial de orégano mexicano; debido al contenido de aceite esencial. Su contenido de metabolitos secundarios se relaciona con el proceso de germinación y actividad biológica de muchas plantas dependiendo de la dosis. Los cereales juegan un papel primordial en la vida alimenticia del hombre por la fuente de nutrientes que proporciona, así como la gran importancia económica, en México se hace necesario estudiar el Maíz Cebú y Sorgo , los cuales por sus características agronómicas y nutricionales pudieran aportar grandes beneficios en la alimentación, a nivel mundial. Se evaluó el efecto de timol y carvacrol durante la germinación de semillas de maíz y sorgo. Se colocaron 20 semillas por caja petri en cuatro grupos de 15 cajas para cada tratamiento: 2,1, 0.1 (ppm) y el control. A los 9 días se cortó por separado radícula, coleoptilo y endospermo. Los resultados para peso seco de coleoptilo y radícula mostraron diferencias significativas entre los tratamientos pero no entre las especies, mientras que para el peso seco del endospermo las diferencias son significativas tanto entre genotipos como entre tratamientos. A menor concentración existe un estímulo en el crecimiento. Los extractos de orégano podrían funcionar como estimulantes naturales

Rendimiento de grano en líneas de sorgo cultivadas bajo riego y riego limitado en Texas

El objetivo de este trabajo fue evaluar, bajo riego y riego limitado, el rendimiento de grano de 40 líneas F7 de sorgo (Sorghum bicolor L. Moench) seleccionadas por tolerancia a sequía en la Facultad de Agronomía de la Universidad Autónoma de Nuevo León (FAUANL) en Marín, Nuevo León, México. Los estudios se efectuaron en College Station, Texas, en el ciclo Otoño-Invierno 2011, y en Lubbock, Texas en el ciclo Primavera-Verano 2011. Las 40 líneas se dividieron en dos grupos de 20 genotipos para integrar dos experimentos, más cinco líneas experimentales y un híbrido comercial como testigo. Entonces, se estudiaron 26 tratamientos, con dos repeticiones. Se utilizó un diseño de bloques completos al azar con covarianza, con el número de plantas por parcela como covariable independiente y el rendimiento de grano de sorgo como variable dependiente. El rendimiento de grano por planta fue en general mayor en College Station que en Lubbock. En ambas localidades, tanto en riego como en riego limitado, se identificaron líneas F7 cuyo rendimiento de grano fue estadísticamente superior a aquel del híbrido testigo y de las líneas que participaron en la cruza que dio origen a la F2 de la cual se seleccionaron

Fire effects on C and H isotopic composition in plant biomass and soil: Bulk and particle size fractions

This work studies carbon (C) and hydrogen (H) isotope composition of plant biomass and soil organic matter (SOM) in an attempt to assess both, changes exerted by fire and possible inputs of charred materials to the soil after a wildfire. Isotope composition of bulk soil, soil particle size fractions and biomass of the dominant standing vegetation in the area (Quercus suber) from Doñana National Park (SW-Spain) were studied by isotope ratio mass spectrometry (IRMS). SOM C isotope composition indicates the occurrence of two SOM pools with different degree of alteration. Coarse soil fractions (>0.5 mm) were found 13C depleted with δ13C values close to those in leaf biomass, pointing to a predominance of poorly transformed SOM. Conversely, fine fractions (0.5 mm) displayed significant lower δ2H values than the intermediate and fine ones (<0.5 mm), again similar to those in leaf biomass (c. -80‰), whereas the fine fractions were found deuterium (2H)-enriched with significant higher δ2H values (c. 50‰), suggesting physical speciation of H depending on soil particle size. The fire produced a significant 2H depletion (Δ2H c. -10‰) in the finer fractions (<0.1 mm). The study of stable isotope analysis added new information and complements the results obtained by other proxies to better understand the effect of fire on SO