As the skin is the main protective organ of the body, it is exposed to wounds or injuries which carry out a healing process during a period of approximately 15 days depending on the severity of the ...injury. In the present research, the development of chitosan-based hydrogels loaded with silver nanoparticles and calendula extract (Ch-AgNPs-Ce) was proposed. This can be used to fulfill the hemostatic, anti-infective, antibacterial, healing and anti-inflammatory functions through controlled release of the nanoparticles and calendula extract in substitution of commonly used drugs. The physical properties of the silver nanoparticles were analyzed by UV–visible spectroscopy, scanning and transmission electron microscopy, showing a size between 50 and 100 nm. The antibacterial properties were evaluated by the agar well diffusion method. Antimicrobial testing of the hydrogels showed that the inclusion of silver nanoparticles provides concentration-dependent antibacterial behavior against E. coli and S. aureus. The healing properties of the system were tested in two diabetic patients to whom said hydrogels were placed, obtaining a positive curative result after a few weeks. Therefore, it can be concluded that Ch-AgNPs-Ce hydrogels can achieve healing in chronic or exposed wounds after a period of time which can be used in alternative treatments in patients with poor healing capacity.
Watertightness test standards are used to evaluate enclosure components in terms of water penetration resistance. Currently, there is a wide variety of watertightness tests in use for façades ...elements and wall systems. However, recent research has revealed many inconsistencies in the possibility of current test standards to reproduce real exposure conditions. As such, the main test parameters specified in watertightness test standards have been called into question. Nonetheless, these studies do not pay attention to the protocols and the technical specifications incorporated in the test standards. Neither to the influence that these aspects could have on the watertightness results. The present paper provides a general overview of current watertightness tests standards from around the world. Thereafter, a thorough comparison of the technical specifications incorporated in the protocols of the test standards has been carried out. Finally, an evaluation and discussion of some parameters suggested in the tests standards is undertaken based on the state of the art and laboratory experiments over diverse mock-ups.
The adequate protection against meteorological conditions of rear-ventilated façades rests on the optimization of the construction design for the joints, cavity depths and wall interfaces. In the ...late 1990s and early 2000s several authors analysed the water management characteristics of open joints in rainscreen systems, although only few of them attempted to quantify infiltration rates into the air cavity. However, none of these studies provided reliable quantitative data on wind-driven rain intrusion to the water resistive barrier of rear-ventilated façades. The provision of this data will give the means of determining the moisture load to which the façade is to be subjected during a rain event and for which the façade must be able to manage. Consequently, the aim of his paper is to compare quantitatively the water management characteristics of different types of rear-ventilated façade systems by adopting a holistic approach to this kind of enclosure system. In order to conduct this study, three façade systems have been selected based on the type of fixing method and the design of the vertical and horizontal joints. Afterwards, the full-scale mock-ups have been built and tested in controlled laboratory conditions. During these tests, the amount of water infiltrating into the air cavity and the amount of water reaching the water resistive barrier have been measured. Finally, a comparison between the results obtained for every mock-up has been made.
The chilhuacle chili (Capsicum annuum L.) is a Mexican native variety whose production has been highly valuable because it is the main ingredient of the Oaxacan black mole, a typical Mexican dish. It ...is basically grown in the Cañada Region of the State of Oaxaca, Mexico, within the Tehuacán-Cuicatlán Biosphere Reserve. Importantly, it is cultivated under traditional agricultural systems, where a range of agronomic constraints associated with the production process and the incidence and severity of pests and diseases represent significant impediments that hinder the yield potential. Additionally, the genetic basis of the crop is highly restricted. Under such environmental and production conditions, the mean crop yield of chilhuacle chili can reach 1 t ha−1 of dehydrated fruits, which can be used in the food, chemical, and pharmaceutical industries. In this review we summarize the current progress on chilhuacle chili cultivation and outline some crucial guidelines to improve production, as well as other research topics that need to be further addressed.
Beans (
spp.) are one of the most important legumes for their nutritional value and health benefits in many world regions. In addition to
, there are four additional species that are cultivated in ...many regions of the world and are a source of food for human consumption:
,
,
, and
In this work, phenolic compounds, antioxidant activity, and anti-nutritional compounds of 18 bean accessions, corresponding to four different species of the genus
, were analyzed. In addition, their physical characteristics, proximate composition, and amino acid content were determined in order to compare their phytochemical composition and nutritional value. The species closest to each other in terms of essential amino acid content were
with
and
with
Furthermore, there was a strong positive correlation between antioxidant activity and flavonoids, anthocyanins, and lectins with all the accessions collected. Significant differences in the content of phenolic compounds were found among the bean species studied. Therefore, in addition to
, other species such as
and
have high biological and antioxidant potential that could be beneficial to human health when consumed as nutraceutical foods.
The use of selenium nanoparticles (SeNPs) in the biomedical area has been increasing as an alternative to the growing bacterial resistance to antibiotics. In this research, SeNPs were synthesized by ...green synthesis using ascorbic acid (AsAc) as a reducing agent and methanolic extract of
L. flowers as a stabilizer. Characterization of SeNPs was performed by UV-vis spectrophotometry, infrared spectrophotometry (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) techniques. SeNPs of 40-60 nm and spherical morphologies were obtained. The antibacterial activity of marigold extracts and fractions was evaluated by disk diffusion methodology. The evaluation of SeNPs at different incubation times was performed through the colony-forming unit (CFU) count, in both cases against
,
, and
bacteria. Partial antibacterial activity was observed with methanolic extracts of marigold leaves and flowers and total inhibition with SeNPs from 2 h for
, 1 h for
, and 30 min for
In addition, SeNPs were found to exhibit antioxidant activity. The results indicate that SeNPs present a potentiated effect of both antimicrobial and antioxidant activity compared to the individual use of marigold extracts or sodium selenite (Na
SeO
). Their application emerges as an alternative for the control of clinical pathogens.
Cerium (Ce) belongs to the rare earth elements (REEs), and although it is not essential for plants, it can stimulate growth and other physiological processes. The objective of this research was to ...evaluate the effect of Ce on seed germination, initial seedling growth, and vegetative growth in rice (Oryza sativa L.) cv. Morelos A-98. During the germination process, the seeds were treated with Ce concentrations of 0, 4, 8, and 12 μM; after 5 d, germination percentage was recorded and after 10 d seedling growth was measured. For vegetative growth, a hydroponic system was established where 14-d-old plants without previous Ce treatment were transferred into nutrient solution. After two weeks of acclimatizing, 0, 25, 50, and 100 μM Ce were added to the nutrient solution for 28 d. Ce significantly increased germination and the initial growth variables of the seedlings. During vegetative growth, Ce increased plant height, number of tillers, root volume, and shoot fresh and dry biomass, without affecting root biomass weight. With low Ce concentrations (25 and 50 μM), the concentrations of chlorophylls and amino acids in the shoots were similar to those in the control, like amino acid concentration in the roots at a concentration of 25 μM Ce. Conversely, the concentration of total sugars increased in the shoot with the application of 25, 50, and 100 μM Ce, and in the roots with the application of 50 μM Ce. Also, Ce did not affect the concentration of macro or micronutrients in the shoots. However, in the roots, the high Ce concentration decreased the concentrations of Ca, Fe, Mn, and Zn, while the Mg concentration increased. Our results indicate that Ce, at the right concentrations, can function as a biostimulant in rice germination and growth.
•Heavy metal concentrations in the SPM were high during the dry period than in the rains.•The volumetric levels of SPM depicted the influence of oceanic waters.•Calculated Toxic Risk Index indicated ...low toxic risk to the benthos living in the lagoon.•The mean –ERM- Quotient denoted 9% probability of toxicity to the biota.
The present study aimed to evaluate multi-element concentrations (Al, As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sr) in suspended particulate material (SPM) collected from Ensenada de La Paz (ELP) lagoon, Baja California Sur, Mexico in two different periods (September and May) to comprehend their origin, geochemical behavior, mass transfer and associated ecotoxicological risks. The 24 hr variation coefficient of volumetric SPM levels were found to be 51.7% in September and 40.5% in May, signifying the effects of oceanic waters. The calculated enrichment factor (EF) values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM, and in this study, Mo had the highest EF of 46.77 probably due to its origin from continental weathering. From the ecotoxicological perspective, the integrated toxic risk index revealed low toxic risk to the benthic community. However, the mean-ERM-Quotient calculated using the particulate concentrations of As, Cd, Cr, Cu, Ni, Pb indicated 9% probability of toxicity to biota. The comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELP lagoon signify low to moderate contamination.
Display omitted
PDF
