•A machine vision system was designed to detect defects on machined metal parts.•Defects, very similar to the surface finishing, can be detected.•The basis of the image processing is image ...fusion.•The machine vision system is assessed following the measurement system analysis.
Suppliers of metallic components with high-precision surfaces are facing a trend towards zero-defect tolerance regarding their finishing. Because of the lack of standardization and the difficulty of the task, this inspection is generally done manually. This work aims to detect defects on machined metal parts even if their orientation and shape are very similar to the surface finishing. A machine vision system, performing the detection of flaws on textured surfaces is fully described. One of its main devices, the lighting system, has been carefully designed to ensure the imaging of defects. Hence, multiple images are acquired under different lighting conditions, processed separately, and merged into one. Features extracted from this fused image and the former processing steps establish the feature space for a supervised learning classifier based on artificial neural networks. Results of the automated inspection show that the system works effectively with a low value of false rejections, which makes it suitable for industrial applications.
A set of benzophenone-derived bisphosphonium salts was synthesized and assayed for lethal activity on the human protozoan parasite Leishmania. A subset of them, mostly characterized by phosphonium ...substituents with an intermediate hydrophobicity, inhibited parasite proliferation at low micromolar range of concentrations. The best of this subset, 4,4′-bis((tri-n-pentylphosphonium)methyl)benzophenone dibromide, showed a very scarce toxicity on mammalian cells. This compound targets complex II of the respiratory chain of the parasite, based on (i) a dramatically swollen mitochondrion in treated parasites, (ii) fast decrease of cytoplasmic ATP, (iii) a decrease of the electrochemical mitochondrial potential, and (iv) inhibition of the oxygen consumption rate using succinate as substrate. Thus, this type of compounds represents a new lead in the development of leishmanicidal drugs.
The goal of this paper was aimed to the formulation of nanoparticles by using two different propyl-starch derivatives – referred to as PS-1 and PS-1.45 – with high degrees of substitution: 1.05 and ...1.45 respectively. A simple o/w emulsion diffusion technique, avoiding the use of hazardous solvents such as dichloromethane or dimethyl sulfoxide, was chosen to formulate nanoparticles with both polymers, producing the
PS-1 and
PS-1.45 nanoparticles. Once the nanoparticles were prepared, a deep physicochemical characterization was carried out, including the evaluation of nanoparticles stability and applicability for lyophilization. Depending on this information, rules on the formation of
PS-1 and
PS-1.45 nanoparticles could be developed. Encapsulation and release properties of these nanoparticles were studied, showing high encapsulation efficiency for three tested drugs (flufenamic acid, testosterone and caffeine); in addition a close to linear release profile was observed for hydrophobic drugs with a null initial burst effect. Finally, the potential use of these nanoparticles as transdermal drug delivery systems was also tested, displaying a clear enhancer effect for flufenamic acid.
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Background
Spanish population is rather homogeneous in its genetic and sociocultural characteristics, but allergen sensitization shows wide geographical variations. We aimed at assessing whether ...sensitization to different allergens in the diverse geographical areas induced different clinical and quality‐of‐life characteristics in adult patients with a first‐time diagnosis of rhinitis and/or asthma.
Methods
Two sequential, identically designed studies were carried out to evaluate such associations (PERFILAR I and II). PERFILAR II was an extension of PERFILAR I with additional allergens being included. Both phases were epidemiological, descriptive, cross‐sectional, nonintervention multicenter studies. Participants were required to have lived for at least the last 2 years in the geographical zone. Asthma control assessment was based on ACQ‐5. Health‐related quality of life was evaluated with validated scales for rhinitis (ESPRINT‐15) and asthma (Mini‐AQLQ). Skin prick tests were used to identify sensitization to involved allergens.
Results
A total of 301 physicians recruited 2711 patients for PERFILAR I+II. Sensitization to allergens was significantly different in patients with rhinitis with/without asthma. Seasonal allergens were associated with rhinitis, a longer time to asthma development, and more severe and commonly intermittent rhinitis. HDM were associated with more common rhinitis, and Alternaria was associated with asthma. The study confirms an association of geographical areas with relevant allergens and allergic clinical picture.
Conclusion
Different types of aeroallergens and specific sensitization profiles are associated with different allergic clinical pictures (rhinitis with/without asthma), different clinical symptoms, and different levels of severity. This could have implications to predict later clinical course and to select appropriate management approaches.
Response surfaces of: (a) efficiency η; (b) pumping power II; and (c) mixing energy cost mec.
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•The response surface methodology has been used to optimize a micromixing unit.•The grid ...convergence study shows that previous results from the same geometry have a huge uncertainty.•Depending on different targets, different optimal geometries are proposed.•The geometry giving the highest mixing efficiency is shown to be also good when it works as a microreactor.
The optimization of a mixing unit by means of CFD (computational fluid dynamics) and RSM (response surface methodology) is presented in this work. The starting geometry is the one studied by Fang and co-workers 14 consisting in a T-type microchannel with the mixing unit inserted in the straight main channel. The mixing takes place at a very low Reynolds number and is promoted by means of two bars at 69° each with respect to the mixing unit walls. These angles are the input parameters of the optimization process while the output ones are the mixing efficiency, the needed pumping power to run the channel and the mixing energy cost. Fang and co-workers found numerically an efficiency of around 22% when one mixing unit was employed, while an almost perfect mixing could be reached by using 28 of them. However, they did not carry out a grid convergence study and their results were got for just one mesh. Due to this, before the optimization tasks and thanks to the Grid Convergence Index, it is shown that Fang and co-workers’ mixing efficiency has an uncertainty of around 40%. This is due to the fact that, with the optimal grid, the mixing efficiency is around 12.5% which is quite far from what Fang and co-workers said. Additionally, with the RSM and by using the optimal mesh, it is found that the optimal angles α1 and α2 are: ∼76° and ∼62° to get the highest efficiency which is around 14%; and ∼72° and ∼74° to get both the lowest pumping power to run the channel and the lowest mixing energy cost. The performing of the micromixer as a microreactor, where a basic reaction must take place, is finally assessed.
Light–matter interaction at the atomic scale rules fundamental phenomena such as photoemission and lasing while enabling basic everyday technologies, including photovoltaics and optical ...communications. In this context, plasmons, the collective electron oscillations in conducting materials, are important because they allow the manipulation of optical fields at the nanoscale. The advent of graphene and other two-dimensional crystals has pushed plasmons down to genuinely atomic dimensions, displaying appealing properties such as a large electrical tunability. However, plasmons in these materials are either too broad or lying at low frequencies, well below the technologically relevant near-infrared regime. Here, we demonstrate sharp near-infrared plasmons in lithographically patterned wafer-scale atomically thin silver crystalline films. Our measured optical spectra reveal narrow plasmons (quality factor of ∼4), further supported by a low sheet resistance comparable to bulk metal in few-atomic-layer silver films down to seven Ag(111) monolayers. Good crystal quality and plasmon narrowness are obtained despite the addition of a thin passivating dielectric, which renders our samples resilient to ambient conditions. The observation of spectrally sharp and strongly confined plasmons in atomically thin silver holds great potential for electro-optical modulation and optical sensing applications.
Consensus document on dog and cat allergy Dávila, I.; Domínguez‐Ortega, J.; Navarro‐Pulido, A. ...
Allergy (Copenhagen),
June 2018, 2018-06-00, 20180601, Letnik:
73, Številka:
6
Journal Article
Recenzirano
The prevalence of sensitization to dogs and cats varies by country, exposure time and predisposition to atopy. It is estimated that 26% of European adults coming to the clinic for suspected allergy ...to inhalant allergens are sensitized to cats and 27% to dogs. This document is intended to be a useful tool for clinicians involved in the management of people with dog or cat allergy. It was prepared from a consensus process based on the RAND/UCLA method. Following a literature review, it proposes various recommendations concerning the diagnosis and treatment of these patients, grounded in evidence and clinical experience. The diagnosis of dog and cat allergy is based on a medical history and physical examination that are consistent with each other and is confirmed with positive results on specific IgE skin tests. Sometimes, especially in polysensitized patients, molecular diagnosis is strongly recommended. Although the most advisable measure would be to avoid the animal, this is often impossible and associated with a major emotional impact. Furthermore, indirect exposure to allergens occurs in environments in which animals are not present. Immunotherapy is emerging as a potential solution to this problem, although further supporting studies are needed.
With the increasing competitiveness in the vine market, coupled with the increasing need for sustainable use of resources, strategies for improving farm management are essential. One such effective ...strategy is the implementation of precision agriculture techniques. Using photogrammetric techniques, the digitalization of farms based on images acquired from unmanned aerial vehicles (UAVs) provides information that can assist in the improvement of farm management and decision-making processes. The objective of the present work is to quantify the impact of the pest Jacobiasca lybica on vineyards and to develop representative cartography of the severity of the infestation. To accomplish this work, computational vision algorithms based on an ANN (artificial neural network) combined with geometric techniques were applied to geomatic products using consumer-grade cameras in the visible spectra. The results showed that the combination of geometric and computational vision techniques with geomatic products generated from conventional RGB (red, green, blue) images improved image segmentation of the affected vegetation, healthy vegetation and ground. Thus, the proposed methodology using low-cost cameras is a more cost-effective application of UAVs compared with multispectral cameras. Moreover, the proposed method increases the accuracy of determining the impact of pests by eliminating the soil effects.
Contributing to the need for new graphene nanoribbon (GNR) structures that can be synthesized with atomic precision, we have designed a reactant that renders chiral (3,1)-GNRs after a multistep ...reaction including Ullmann coupling and cyclodehydrogenation. The nanoribbon synthesis has been successfully proven on different coinage metals, and the formation process, together with the fingerprints associated with each reaction step, has been studied by combining scanning tunneling microscopy, core-level spectroscopy, and density functional calculations. In addition to the GNR’s chiral edge structure, the substantial GNR lengths achieved and the low processing temperature required to complete the reaction grant this reactant extremely interesting properties for potential applications.
Increasingly high hopes are being placed on organic semiconductors for a variety of applications. Progress along these lines, however, requires the design and growth of increasingly complex systems ...with well‐defined structural and electronic properties. These issues have been studied and reviewed extensively in single‐component layers, but the focus is gradually shifting towards more complex and functional multi‐component assemblies such as donor–acceptor networks. These blends show different properties from those of the corresponding single‐component layers, and the understanding on how these properties depend on the different supramolecular environment of multi‐component assemblies is crucial for the advancement of organic devices. Here, our understanding of two‐dimensional multi‐component layers on solid substrates is reviewed. Regarding the structure, the driving forces behind the self‐assembly of these systems are described. Regarding the electronic properties, recent insights into how these are affected as the molecule's supramolecular environment changes are explained. Key information for the design and controlled growth of complex, functional multicomponent structures by self‐assembly is summarized.
The variety of applications for organic materials is continuously growing and includes increasingly complex functionalities. This requires the synthesis and growth of ever more refined molecular thin films and structures. The use of multiple molecular components greatly increases the range of achievable structures and functionalities. Key knowledge for a controlled and rational growth of multicomponent monolayer assemblies is summarized.
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