Frequent and accurate inspections of industrial components and equipment are essential because failures can cause unscheduled downtimes, massive material, and financial losses or even endanger ...workers. In the mining industry, belt idlers or rollers are examples of such critical components. Although there are many precise laboratory techniques to assess the condition of a roller, companies still have trouble implementing a reliable and scalable procedure to inspect their field assets. This article enumerates and discusses the existing roller inspection techniques and presents a novel approach based on an Unmanned Aerial Vehicle (UAV) integrated with a thermal imaging camera. Our preliminary results indicate that using a signal processing technique, we are able to identify roller failures automatically. We also proposed and implemented a back-end platform that enables field and cloud connectivity with enterprise systems. Finally, we have also cataloged the anomalies detected during the extensive field tests in order to build a structured dataset that will allow for future experimentation.
Résumé
Objectif
Proposer un algorithme diagnostique rationnalisant l’utilisation de la ponction lombaire (PL) dans le diagnostic de l’hémorragie sous-arachnoïdienne (HSA) et ne la réservant qu’aux ...patients à haut risque.
Méthode
Nous avons effectué une revue extensive de la littérature de 2009 à 2014, dans la base de données Medline/Pubmed, avec les termes
Aneurysmal Subarachnoid Hemorrhage
(MeSH Term) et
Diagnosis
(MeSH Term) et nous avons dérivé de ces résultats un algorithme diagnostique intégrant les aspects cliniques, l’imagerie par tomodensitométrie (TDM) et la recherche de xanthochromie par PL.
Résultats
Mille neuf cent quatre articles ont été identifiés, dont quatre-vingt dix-huit ont été inclus dans l’analyse. De cette analyse a été dérivé un algorithme diagnostique d’une céphalée suspecte d’HSA, avec indication au recours à la PL selon la probabilité clinique intégrant le délai depuis l’apparition des symptômes et le score d’Ottawa notamment.
Conclusions
La PL avec recherche de xanthochromie garde sa place dans le diagnostic de l’HSA, mais son utilisation peut être rationnalisée. L’algorithme proposé ne la réserve qu’aux patients à haut risque, notamment lorsque les performances de l’imagerie ne sont plus assez bonnes.
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•Ultrasound (US) increases the Ag surface loading on TiO2.•The support is micrometric TiO2, which eliminates health risks associated to nanoparticles.•Under US, Ag crystallites range ...from 1 to 10nm vs. 0.3 to 3nm.•Aggregates of Ag nanoparticles increase the visible light absorption compared to nano-disperse Ag.•Samples obtained with US degrade 3–11% more acetone in 6h.
Titanium dioxide is the most popular photocatalyst to degrade organic pollutants in air, as well as in water. The principal drawback preventing its commercial application lies in its limited absorption of the visible light (400–700nm), while it is active under UV irradiation (≤387nm). Supporting noble metals in the form of nanoparticles on TiO2 increases its activity in the visible range. However, both the synthesis of noble metal nanoparticles and their deposition on TiO2 are multi-step processes that often require organic solvents. Here, we deposit Ag nanoparticles from AgNO3 on the surface of micrometric TiO2 with H2O as a solvent and under ultrasound irradiation at 30Wcm−2. Ultrasound increases the surface amount of Ag on TiO2 with heterogeneous size distribution of Ag nanoparticles, which are bigger and overlaid (1–20nm vs. 0.5–3nm) compared to the sample obtained in traditional conditions (TEM images). While this change in morphology had no effect on acetone photodegradation under UV light, the 5%, 10%, and 20% Ag-TiO2 degraded 17%, 20% and 24% acetone under visible light, respectively. The 10% by weight Ag-TiO2 sample obtained in absence of ultrasound only degraded 14% acetone in 6h, while the bare TiO2 was not active.
Extreme environmental events can strongly affect coastal marine ecosystems but are typically unpredictable. Reliable data on benthic community conditions before such events are rarely available, ...making it difficult to measure their effects. At the end of October 2018, a severe storm hit the Ligurian coast (NW Mediterranean) producing damages to coastal infrastructures. Thanks to recent data collected just before the event on two Posidonia oceanica seagrass meadows hit by the storm, it has been possible to assess the impact of the event on one of the most valuable habitats of the Mediterranean Sea. By means of seagrass cover and depth data gathered along four depth transects positioned within the two meadows in areas differently exposed to the storm waves, and by using models (WW3® + SWAN + XBeach 1D) to evaluate wave height and bed shear stress, we showed that meadows experienced erosion and burial phenomena according to exposure. Paradoxically, meadows in good conditions suffered more damage as compared to those already suffering from previous local anthropogenic impacts. Besides the direct effect of waves in terms of plant uprooting, a major loss of P. oceanica was due to sediment burial in the deepest parts of the meadows. Overall, the loss of living P. oceanica cover amounted to about 50%. Considering that previous research showed that the loss of the original surface of P. oceanica meadows in 160 years due to anthropogenic pressures was similarly around 50%, the present study documented that an extreme environmental event can generate in a single day a loss of natural capital equal to that produced gradually by more than a century of human impact.
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•Extreme weather events may affect severely the submerged benthic habitats.•Posidonia oceanica meadows halved their living cover.•The loss of P. oceanica in one day equate that lost in 160 years by human impact.
•Positive effect of US in synthesizing Me-modified TiO2 (Me = Ag, Cu, Mn) for pollutants degradation in gas-phase.•Application of ultrasound for the photocatalytic removal of organic compounds in ...water using Ag-doped TiO2.•Combined with photocatalytic water treatment, the organic compounds degradation and mineralization increases.
Sonochemistry is based on acoustic cavitation, which consist in the formation, growth, and implosive collapse of bubbles within a liquid. Collapsing bubbles generate localized hot spots, characterized by temperatures up to 5000 K and pressures up to 1800 atm. These extreme conditions allow producing a variety of nanostructured and amorphous materials, as well as they are advantageous for chemical processes. Ultrasound requires inexpensive equipment and fewer steps than conventional methods. Combining ultrasound and photocatalysis enhances the performance of the processes, reduces reaction time, avoids the use of extreme physical conditions and improves the photocatalytic materials properties increasing their activity. Here, we reported the positive effect of US in synthesizing Me-modified TiO2 (Me = Ag, Cu, Mn) for pollutants degradation in gas-phase; also, we proved the advantageous application of ultrasound for the photocatalytic removal of organic compounds in water. Ultrasound produced more efficient Me-doped TiO2, which showed higher activity in visible light. When combined with photocatalytic water treatment, the organic compounds degradation and mineralization increases.
•Sonophotocatalysis with an ultrasonic power of 50 Wcm−2 degrades 100% of Isoproturon.•Kronos 1077 is a valid and safer photocatalyst to substitute P25.•HPLC-MS detected 7 byproducts of the ...Isoproturon degradation never reported before.•We identified the structure of 3 byproducts for the first time.•Sonophotocatalysis leads to smaller byproducts compared to photocatalysis.
Pollutants of emerging concern contaminate surface and ground water. Advanced oxidation processes treat these molecules and degrade them into smaller compounds or mineralization products. However, little information on coupled advanced oxidation techniques and on the degradation pathways of these pollutants is available to identify possible ecotoxic subproducts. In the present work, we investigate the ultrasound assisted photocatalytic degradation pathway of the herbicide Isoproturon. We worked in batch mode in a thermostatic glass reactor. We compared the activity of nanometric TiO2 P25 with that of Kronos 1077, a micrometric TiO2. We discuss the individual, additive and synergistic degradation action of photolysis, sonolysis, sonophotolysis, and sonophotocatalysis by varying catalyst loading and/or ultrasound power for the last three techniques. With 0.1 g L−1 catalyst, photocatalysis and sonophotopcatalysis completely degrade Isoproturon within 240 min and 60 min, respectively (>99% conversion). Sonophotocatalysis breaks Isoproturon down into smaller molecules than photocatalysis alone.
Graphitic carbon nitride (g-C3N4) is an emerging metal-free photocatalyst, however, engineering the photocatalytic efficiency for the effective degradation of hazardous molecules is still ...challenging. An unstable and low bandgap CuWO4 was composited with g-C3N4 to achieve synergistic benefits of tuning the visible light responsiveness and stability of CuWO4. CuWO4/g-C3N4 nanocomposite exhibited a relatively high visible light absorption region and the bandgap was modified from 2.77 to 2.53 eV evidenced via UV-DRS. Moreover, the fast electron transfer rate was observed with CuWO4/g-C3N4 nanocomposite as confirmed using PL and photocurrent studies. XRD, FT-IR, and HR-TEM analyses signified the formation of CuWO4/g-C3N4 nanocomposite. CuWO4/g-C3N4 nanocomposite showed enhanced photocatalytic degradation of Tetracycline (TC) about ∼7.4 fold greater than pristine g-C3N4 in 120 min. Notably, the OH• and •O2− radicals played a most significant role in photocatalytic TC degradation. Furthermore, the energy band structure, density of state, and Bader charge analyses of these molecules were performed.
•CuWO4/g-C3N4 exhibited enhanced photocatalytic degradation of Tetracycline.•The built-in electric field and the matched energy band triggered Z-scheme system.•The stability of nanocomposite improved up to 6 cycles compared with CuWO4.•The OH.• and •O2− played a significant role in the photocatalytic degradation•The energy band structure, density of state and Bader charge analyses were analysed.
Optical microscopy videos enable experts to analyze the motion of several biological elements. Particularly in blood samples infected with Trypanosoma cruzi (T. cruzi), microscopy videos reveal a ...dynamic scenario where the parasites' motions are conspicuous. While parasites have self-motion, cells are inert and may assume some displacement under dynamic events, such as fluids and microscope focus adjustments. This paper analyzes the trajectory of T. cruzi and blood cells to discriminate between these elements by identifying the following motion patterns: collateral, fluctuating, and pan-tilt-zoom (PTZ). We consider two approaches: i) classification experiments for discrimination between parasites and cells; and ii) clustering experiments to identify the cell motion. We propose the trajectory step dispersion (TSD) descriptor based on standard deviation to characterize these elements, outperforming state-of-the-art descriptors. Our results confirm motion is valuable in discriminating T. cruzi of the cells. Since the parasites perform the collateral motion, their trajectory steps tend to randomness. The cells may assume fluctuating motion following a homogeneous and directional path or PTZ motion with trajectory steps in a restricted area. Thus, our findings may contribute to developing new computational tools focused on trajectory analysis, which can advance the study and medical diagnosis of Chagas disease.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mediterranean marine biodiversity has received only a fraction of the attention accorded to its terrestrial counterpart, despite the great cultural and economic importance that the sea has been ...having for the Mediterranean countries. A rough estimate of more than 8500 species of macroscopic marine organisms should live in the Mediterranean Sea, corresponding to somewhat between 4% and 18% of the world marine species. This is a conspicuous figure if one considers that the Mediterranean Sea is only 0.82% in surface area and 0.32% in volume as compared to the world ocean. The high biodiversity of the Mediterranean Sea may be explained by historical (its tradition of study dates older than for almost any other sea), paleogeographic (its tormented geological history through the last 5 my has been determining the occurrence of distinct biogeographic categories), and ecological (its variety of climatic and hydrologic situations within a single basin has probably no equals in the world) reasons. Present-day Mediterranean biodiversity is undergoing rapid alteration under the combined pressure of climate change and human impact, but protection measures, either for species or ecosystems, are still scarce. To understand the role and patterns of Mediterranean marine biodiversity, marine ecological research should: first, re-value those scientific areas currently unfashionable with funding agencies (systematics, biogeography and taxonomy); second, start monitoring biodiversity with a long-term approach at a whole Mediterranean scale, possibly through an internationally co-ordinated network of marine protected areas.
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