Electrospraying is a technique now applied for the production of food nanoparticles, nanofibres and nanocapsules, which could constitute a good alternative for the development of films. The goal of ...this work was to determine the electrospraying operation conditions and the zein concentration that would allow a film to be produced and also to evaluate the structural characteristics and barrier and thermal properties of films developed at different thicknesses. Results showed that films can be obtained by electrospraying, resulting possible to produce homogeneous films, without electrical arc formation during processing when using a 11.4% zein solution, an electrical voltage of 7.8–8.7 kV and a distance of 1.5 ± 0.5 cm between the nozzle and the deposit plaque. Regarding the effect of the production methods (electrospraying and casting) and the film thickness on film appearance, both variables had significant effect on colour parameters, observing a more yellowish colour (b* = 72.3 ± 6.8) and lower transparency (%T = 90.6 ± 0.21) at larger thicknesses (100 μm), and a smoother and more homogeneous surface (ESEM) when films were obtained by electrospraying. Water vapour permeability was only influenced by film thickness (1.51 × 10−08 to 3.11 × 10−08 g/s-m-Pa) in both methodologies. The glass transition temperatures (Tg) for electrospraying and casting films were different (222 °C and 231 °C respectively) and higher than that of zein powder (165 °C), indicating a possible change in the film structure due to the process. Under the process conditions tested in this work, electrospraying can be considered as an alternative technique to produce films.
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•Electrospraying can be used to produce zein films.•Electrospraying generates similar films to those produce by casting.•Electrosprayied zein generates different products as varying process conditions.
Under greenhouse conditions, we evaluated establishment of four tree species and their capacity to degrade crude oil recently incorporated into the soil; the species were as follows:
Cedrela odorata
...(tropical cedar),
Haematoxylum campechianum
(tinto bush),
Swietenia macrophylla
(mahogany), and
Tabebuia rosea
(macuilis). Three-month-old plants were planted in soil with three treatments of heavy petroleum and a control (C0 0 mg kg
−1
; C1 18,000 mg kg
−1
; C2 31,700 mg kg
−1
; C3 47,100 mg kg
−1
) with four repetitions per treatment and species; the experiment was carried out for 245 days. Height and biomass of all species significantly diminished as petroleum concentration increased, although plant survival was not affected. The quantity of colony-forming units (CFU) of rhizospheric bacteria varied among tree species and treatments; petroleum stimulated bacterial CFU for
S. macrophylla
. The number of fungi CFU for
S. macrophylla
and
T. rosea
was significantly greater in C0 than in soil with petroleum, but among species and among different concentrations, no significant differences were found. The greatest percentage of total petroleum hydrocarbon (TPH) degradation was found in C1 for soil without plants (45 %). Differences from the remaining treatments (petroleum concentrations in soil and plant species) were not significant (
P
< 0.05). Among all trees,
H. campechianum
had the greatest TPH degradation (32.5 % in C2).
T. rosea
(C1) and
H. campechianum
(C2) resulted in petroleum degradation at levels ranging from 20.5 to 32.5 %. On the basis of this experiment, the tree species used did not improve TPH degradation. However, all of them showed high rates of survival and vigor. So, as tree species provide goods and services, experiments with inoculation of hydrocarbonclastic microorganisms, addition of fertilizers, and mixture of tree and grasses are recommended.
Celery, Apium graveolens L. (Apiaceae), is an essential salad ingredient in different parts of the world, and production is principally destined for the fresh market. Celery hosts several insect ...species, including the weevil Listroderes costirostris Schoenher (Coleoptera: Curculionidae). Listroderes costirostris currently is present in the San Quintin Valle, Baja California, Mexico, on commercial celery crops. Hypera postica (Gyllenhal) (Coleoptera: Curculionidae) feeds on several plants of the Fabaceae family and is the principal pest affecting Medicago sativa L. (Fabaceae) alfalfa crops. The purpose of this work was to assess the degree of infestation, spatial distribution, and the association between L. costirostris and H. postica on A. graveolens, in Baja California, Mexico. We established 4 quadrants in 1 ha, and we sampled 100 plants per quadrant in each sample. We collected 22 samplings, counting the larvae and adults of both species. Hypera postica was reported herein for the first time feeding on A. graveolens plants. Between 9.57% and 28.68% of the celery plants served as hosts to both species. Listroderes costirostris had the highest percentage of infested plants. The competitive interaction of these 2 species affected H. postica, which showed lesser abundance. Both species were associated in all the sample quadrants. Listroderes costirostris registered an aggregated distribution pattern, whereas H. postica presented a uniform distribution. The spatial distribution of H. postica is the result of competing for food and space with L. costirostris.
Clinico-pathological correlation studies show that some otherwise healthy elderly individuals who never developed cognitive impairment harbor a burden of Alzheimer's disease lesions (plaques and ...tangles) that would be expected to result in dementia. In the absence of comorbidities explaining such discrepancies, there is a need to identify other brain changes that meaningfully contribute to the cognitive status of an individual in the face of such burdens of plaques and tangles. Glial inflammatory responses, a universal phenomenon in symptomatic AD, show robust association with degree of cognitive impairment, but their significance in early tau pathology stages and contribution to the trajectory of cognitive decline at an individual level remain widely unexplored. We studied 55 brains from individuals at intermediate stages of tau tangle pathology (Braak III-IV) with diverging antemortem cognition (demented vs. non-demented, here termed `resilient'), and age-matched cognitively normal controls (Braak 0-II). We conducted quantitative assessments of amyloid and tau lesions, cellular vulnerability markers, and glial phenotypes in temporal pole (Braak III-IV region) and visual cortex (Braak V-VI region) using artificial-intelligence based semiautomated quantifications. We found distinct glial responses with increased proinflammatory and decreased homeostatic markers, both in regions with tau tangles (temporal pole) and without overt tau deposits (visual cortex) in demented but not in resilient. These changes were significantly associated with markers of cortical cell damage. Similar phenotypic glial changes were detected in the white matter of demented but not resilient and were associated with higher burden of overlying cortical cellular damage in regions with and without tangles. Our data suggest that changes in glial phenotypes in cortical and subcortical regions represent an early phenomenon that precedes overt tau deposition and likely contributes to cell damage and loss of brain function predicting the cognitive status of individuals at intermediate stages of tau aggregate burden (Braak III-IV).
Se elaboró una crema para la piel a base de cáscaras de plátano, ya que en él se encuentran proteínas, carbohidratos, fibra, potasio y vitaminas, las cuales tienen múltiples beneficios. Con el fin de ...disminuir los residuos orgánicos que se generan en los lugares donde se comercializa la fruta, se recolectaron cáscaras de plátano en el basurón de residuos orgánicos del Mercado de Metepec, Estado de México. Se mezclaron con productos de origen vegetal como la glicerina, aceites de almendras, ajonjolí, germen de trigo, cera de abeja, pectina y esencia de plátano. Se aplicaron dos diferentes métodos para la preparación de la crema, el primero fue con alcohol cetílico (C16H34O) y el segundo con cera de abeja. Se obtuvieron dos fases; la fase oleosa y la fase acuosa, ambas mezclas se colocaron a baño maría y finalmente se emulsionaron para realización de la crema. Para comprobar su eficiencia, se aplicaron encuestas a los usuarios (personas de distintas edades), arrojando que se puede aplicar en la piel seca, debido a la capacidad y humectación que la crema tiene en la piel. Este producto se suma a las pequeñas acciones que pueden generar cambios en el ambiente, mediante la disminución de los residuos orgánicos dispuestos en forma unadecuanda y una forma accesible del costo del producto, que es favorable para todos. Como es una prueba prototipo, se está analizando la posibilidad de crear una microempresa que se dedique a la elaboración de dicho producto, obviamente tomando estándares de calidad.
El osteosarcoma (OS) es un tumor maligno de hueso, constituye el 75% en pacientes jóvenes, afecta principalmente huesos de las extremidades inferiores. No existe ningún método eficaz para prevenir ...este tipo de cáncer y puede inducir la amputación. El beta-sitosterol (BS) es un compuesto vegetal. Estudios han demostrado propiedades biomédicas inmunomoduladoras, antimutagénicas, antiinflamatorias y antioxidantes. El benzopireno (BZP) es un hidrocarburo, capaz de inducir OS. Considerando estos antecedentes, se planteó este proyecto de investigación. Por lo que el objetivo fue determinar en un modelo de carcinogénesis ósea en ratas, la actividad quimioterapéutica de beta-sitosterol en el desarrollo del osteosarcoma. Se indujeron lesiones neoplásicas mediante la administración perifemoral de BZP. De la 7ª a la 9ª semana se administró por vía oral BS. Se registró el peso de las ratas, periódicamente se tomaron muestras sanguíneas para realizar estudios de genotoxicidad; se realizaron pruebas bioquímicas mediante para determinar velocidad de sedimentación (VSG), fosfatasa alcalina (FA) y deshidrogenasa láctica (DHL) y tomografía axial computarizada (TAC). Al cumplir la novena semana, se realizó eutanasia, se extrajeron los fémures, tibias, hígado y pulmones para su estudio histopatológico. Los resultados parciales en las ratas, evaluado por el estudio histopatológico demuestran la formación de OS en el fémur tratado. Así mismo el peso en ambas cepas, presentó una disminución estadísticamente significativa de la tercera a la 7ª semana, sin embargo, el peso comenzó a estabilizarse a partir de la 8ª semana. El BZP fue altamente genotóxico en ambas cepas de ratas. Las pruebas bioquímicas presentaron diferencias estadísticamente significativas a partir de la 3ª semana de tratamiento con BZP en los valores de la VSG, FA y DHL, en todas las ratas tratadas, sin embargo, a partir de la 8ª semana se observó una disminución de la FA y DHL en algunos animales administrados con BS. Se concluye que la administración de BZP contribuye a la inducción de OS en las ratas tratadas, y el BS puede ayudar a disminuir la actividad carcinogénica del BZP, lo que nos da la pauta para continuar con otros estudios que permitan considerar el uso del BS en personas con OS.
Concrete carbonation data from 16 test sites in 9 countries (Bolivia, Chile, Colombia, Costa Rica, Mexico, Spain, Uruguay, Portugal, and Venezuela) were compared to identify concrete performance due ...to carbonation at natural exposure conditions after almost six years of exposure. This research is part of the DURACON project ("Effect of the environment on reinforcement durability"), a long-term Ibero-American project intended to correlate the influence of urban and marine meteorochemical parameters on the performance of reinforced concrete structures. Environmental parameters were measured following the ISO 9223 standard. Concrete was physically characterized by the results of compressive strength, elastic modulus, total and effective porosity, and water absorption resistance (Fagerlund method) laboratory tests. Concrete specimens (with and without steel reinforcement bars-rebars) were prepared for electrochemical and physical/mechanical/chemical tests using materials available in each country. Concrete composition was kept similar between specimens by following strict preparation protocols. Two water/cement (w/c) ratios were used: 0.45 w/c ratio concrete had a minimum cement content of 400 kg/m sigma up 3 times and 0.65 w/c ratio concrete had a minimum 28-day compressive strength of 210 kg/cm sigma up 2 greater than or equal to Materials were type I Portland cement, siliceous sand, and crushed rock as coarse aggregates (13-mm maximum nominal size). After six years of exposure, corrosion potentiality and probability analysis of the reinforcement at the different sites indicated the concrete prepared in Venezuela to have the highest probability of experiencing carbonation-induced reinforcement corrosion. The concrete prepared at the Cali, Colombia, site had the lowest probability. Carbonation aggressiveness was found to be highest at tropical sites, with the Venezuela sites exhibiting the most aggressive conditions among the participating countries.
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