•Characterization of a solar cell parameters using artificial neural networks.•Based solely on the information of the data sheet.•Generation of synthetic data to train the network.•The obtained ...parameters will always be unique for each input provided.•The method can be applied to other similar characterization problems.
This article presents a method to estimate the parameters of a photovoltaic cell model in its equivalent circuit of a single-diode using artificial neural networks; more specifically, the multilayer perceptron concept is used. The data required to estimate the parameters are based solely on the information available in the manufacturer’s data sheet. The neural network has two hidden layers and the selected training method was Bayesian regularization. The training data were produced synthetically to ensure that a large part of the range of possible parameter values is covered. The network performance is validated with a data set not included in the training set, making the comparison with a recognised method from the literature, and even more, with experimental data obtained from a real photovoltaic panel. The main advantage of this method is that, once the network is trained, the parameters returned by the network will always be unique for each input provided, which is not the case with other artificial intelligence methods such as genetic algorithms or differential evolution. In addition, this method can be directly applied to other similar problems, only by modifying the inputs and outputs of the network.
Skin wound healing is a complex biochemical process of tissue repair and remodeling in response to injury. Currently, the drugs used to improve the healing process are inaccessible to the population, ...are costly, and have side effects, making the search for new treatment alternatives necessary. Propolis is a natural product produced by bees that is widely recognized and used in folk medicine for its multiple biomedical activities. However, therapeutic information regarding Mexican propolis is limited. This study aimed to evaluate the wound-healing effect of the Chihuahua ethanolic extract of propolis (ChEEP). Macroscopic and histological analyses were performed using a mouse wound-healing model. The topic acute toxicity assay showed that propolis at 10% w/v had no toxic effects. ChEEP has antibacterial activity against the Gram-positive bacteria
and
. Moreover, it exhibited good anti-inflammatory activity evaluated through mouse ear edema induced by 12-O-tetradeca-noylphorbol-13-acetate (TPA). A full-thickness incision lesion was created in mice and treated topically with 10% ChEEP. At Day 14 post-treatment, it was observed that propolis increased wound contraction and reduced healing time and wound length; furthermore, propolis increased the tensile strength of the wound, as determined with the tensiometric method, and promoted the formation of type I collagen at the site of injury, as evaluated with Herovici stain. These findings suggest that the topical administration of ChEEP can improve skin wound healing, probably due to the synergistic effect of its components, mainly polyphenols, in different steps of the wound-healing process. It should be noted this is the first time that the wound-healing activity of a Mexican propolis has been evaluated.
A comparative investigation of the chiral amplification features of a series of three families of C3‐symmetric tricarboxamides, 1,3,5‐triphenylbenzenetricarboxamides (TPBAs), benzenetricarboxamides ...(BTAs) and oligo(phenylene ethynylene) tricarboxamides (OPE‐TAs), is here reported. As previously observed for BTAs and OPE‐TAs, a similar dichroic response is obtained for TPBAs decorated with one, two or three chiral side chains bearing stereogenic centers, thus confirming the efficient transfer of point chirality to the supramolecular helical aggregates. Unlike BTAs and OPE‐TAs, the chiral amplification ability of TPBAs in majority rules experiments shows a negligible dependence on the number of chiral centers per monomeric unit, and stands the largest among the series of tricarboxamides. Detailed experimental and theoretical studies demonstrate that the rotation angle between the TPBA units in the helical stack is intermediate to that observed for BTAs and OPE‐TAs. This feature strongly conditions the steric interactions between vicinal molecules in the stack and the final chiral amplification outcome. Furthermore, theoretical calculations show that achiral side chains favor the interdigitation of the helical aggregates and thereby the formation of bundle superstructures.
A comparative investigation of the chiral amplification features of a series of three families of C3‐symmetric tricarboxamides, namely TPBAs, BTAs, and OPE‐TAs, is reported. Whilst the transfer of point chirality of the three families is similar, the ability for chiral amplification is very different. The number of stereogenic centers per monomeric unit strongly conditions chiral amplification in BTAs and OPE‐TAs but exerts a negligible effect in TPBAs.
La Plataforma NoGracias es una organización de la sociedad civil que ejerce acción en defensa de un sistema sanitario público democrático (transparente y responsable ante los ciudadanos) y soberano ...(sus decisiones no quedan dictadas por los intereses de otros actores, como las industrias). Queda inscrita en el racionalismo respecto a su confianza en la ciencia y su método, pero a la vez es crítica con las derivas que ha tomado el encaje racionalista de la medicina contemporánea, esto es, la medicina basada en la evidencia. Opera en un escenario en el que el Estado ha perdido sus fortalezas clásicas en favor de grupos empresariales y donde el acceso al proceso político no es sencillo. A lo largo de sus más de 10 años de historia, la Plataforma ha construido un marco teórico que desafía a grandes poderes y ahora recorre un largo camino hacia su institucionalización.
NoGracias group is a civil society organization that takes action in defense of a democratic (transparent and accountable to citizens) and sovereign public health system (its decisions are not dictated by the interests of other actors such as industries). It is inscribed in rationalism regarding its confidence in science and its method, but at the same time it is critical of the drifts that the rationalist fit of contemporary medicine has taken, that is, evidence-based medicine. It operates in a scenario in which the State has lost its classic strengths in favor of business groups and where access to the political process is not easy. Throughout its more than ten years of history, NoGracias has been able to build a theoretical framework that challenges great powers and goes a long way toward its institutionalization.
The chiroptical features of supramolecular polymers formed from N‐heterotriangulenes 1–3 have been investigated by circular dichroism (ECD) and vibrational circular dichroism (VCD) techniques. In ...solution, the CD spectra demonstrate that the helicity of the aggregates depends on only the stereogenic centres located at the peripheral chains. In the gel state, the chiroptical features are conditioned by the point chirality of the stereogenic centres and by the achiral solvent utilised. Sonication of the gels formed in CCl4 reveals both kinetic and thermodynamic phases. These findings reveal the presence of pathway complexity in the gel state triggered by sonication. The described solvent‐induced helical stereomutation demonstrates that the gel state can be utilised as an outstanding benchmark for investigating uncommon chiroptical effects and to explore the rules of chirality transmission.
Twists and turns: The chiroptical features of supramolecular polymers formed from N‐heterotriangulenes 1–3 have been investigated by circular dichroism and vibrational circular dichroism techniques. Solvent‐directed pathway complexity, yielding kinetic or thermodynamic aggregates, is observed for N‐heterotriangulenes 1–3 in the gel state (see figure).
Purpose
This study presents a prototype smartphone application for occupational dosimetry in interventional practices based on electronic personal dosimeters to assist in dose monitoring.
Methods
The ...prototype receives and records information from the occupational dose report containing the cumulative dose of electronic personal dosimeters worn over the apron at chest level and electronic area dosimeters located on C‐arms (reference dosimeters), for each fluoroscopy‐guided procedure. Using their smartphones, personnel involved in interventional practices can review and compare their occupational records with an investigation level, the dose limits, and their department colleagues (anonymously). The ratio between Hp(10) measured by the personal and the reference dosimeters at the C‐arm is presented as an indicator of consistent use of suspended operator shield. Some general results extracted from the first months of use are presented.
Results
The reference dosimeter located at the C‐arm (without lead protection and acting as an ambient dosimeter) recorded in one of the laboratories 217 mSv during 308 procedures over 5 months, showing an indication of the radiation risk present in an interventional laboratory. The ratio between the personal cumulative dose and the dose at a reference C‐arm dosimeter ranged from 0.2% to 1.67% (a factor of 8.5) for different interventionalists. These differences suggest different protection habits among interventional operators, as well as a target for dose reduction.
Conclusions
With this system, professionals have easy access to their occupational dosimetry records (including information on the workload) in the setting of their interventional departments, to thereby actively engage in the protection process.
Livestock animals, such as swine, are an important source of
in the human population. Currently, there is limited knowledge regarding the potential influence that the
genotype might exert on ...establishing infection in swine. Herein, we investigated the role of 2
isolates, type II and III, representative of the genotypes circulating in Europe, in the immune responses and infection dynamics in piglets. Recently obtained oocysts (10
) from the
field isolates TgShSp1 (type II, ToxoDB genotype #3) and TgShSp24 (type III, #2) were used for oral infection. Thirteen 50-day-old female piglets of the Landrace-Large White crossbreed were randomly allocated into three different groups: Group 1 (G1, n=5), inoculated with TgShSp1; Group 2 (G2, n=5), inoculated with TgShSp24; and Group 3 (G3, n=3), a non-infected control group. Clinical signs were monitored daily until 42 days post-infection (dpi) when piglets were euthanized. Blood samples were collected weekly to test the cellular immune response in parasite-stimulated peripheral blood and specific IgG, IgG1 and IgG2, responses in sera. Parasite distribution and burden were evaluated in target tissues using a mouse bioassay and quantitative RT-PCR (qPCR). Apathy and a moderate decrease in feed consumption were observed in G1 and G2 piglets between 5 and 8 dpi, coinciding with fever (>40°C). G2 piglets had higher temperatures for a longer duration. Using mouse bioassay and qPCR, the detection frequency was higher in G2
G1, and the highest parasite burdens in target tissues were also found in G2. Seroconversion was detected at 14 dpi in both infected groups, but higher antibody levels were observed in G2 piglets. Cytokine analyses revealed the production of IL-8, IL-1β and IFN-ɤ from 7 dpi in both infected groups. Moreover, IL-12 was produced from 7 dpi in G1 and from 14 dpi in G2. Levels of IL-8 were higher in G2, but IL-1β, IL-12 and IFN-ɤ were higher in G1 at 14 dpi. This cytokine profile reveals a predominant proinflammatory response that could be involved in limiting
infection in piglets, although it is more efficient against TgShSp1 type II-driven infection.
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