The flow distribution in the rectangular channel of a laboratory filter-press electrochemical reactor was evaluated using three flow models namely: (a) axial dispersion, (b) sum of two phases and (c) ...fast and stagnant zones. In the case of the axial-dispersion model, several methods have been used to calculate the Peclet number; the moment method, the non-linear least-squares and the Laplace transform technique. Several boundary conditions, involving different physical and experimental assumptions of the flow were used to solve the partial differential equation that describes the flow behaviour. A total of nine expressions to examine flow dispersion has been used. The comparison of experimental and predicted response signals was made by evaluating the root mean squared error. A data fit in real time has been found to be a better choice as solutions based on the evaluation of moments are prone to error due the overweight of the signal at long times. Data fitting in the Laplace plane is very accurate but it does not guarantee a good fit in real time. Models based on the sum of a fast and a slow or stagnant phase resulted in solutions having very low values of the extension of the slow and stagnant phases, the assumption of a single phase with some degree of dispersion was considered more appropriate.
Additive manufacturing (or 3D printing) involves the process of fabricating a part by layer-by-layer assembly of materials with processes such as extrusion, binding, melting, and photopolymerization. ...It is transforming how we assemble our prototypes and, in the future, manufacture our products. There have been a number of materials that can be utilized for this technology, however, high performance polymer nanocomposites are a very important class of material that is just recently being used in additive manufacturing. High performance polymer is a group of polymer materials that are known to retain its desirable mechanical, thermal, and chemical properties when subjected to harsh environment such as high temperature, high pressure, and corrosive chemicals. When mixed with nanofillers such as carbon nanotube, nanoclay, and graphene, these polymers can have improved mechanical properties and sometimes acquire properties that were not present initially like thermal and electrical conductivity. This review article aims to summarize available additive manufacturing techniques, high performance polymers and nanofillers available, and research efforts on its use for additive manufacturing.
•Current significance of chlor-alkali, chlorate, aluminium and zinc industries.•New challenges in energy management related to PEM and Solid Oxide Fuel Cells and Redox Flow Batteries.•Promising ...environmental applications in industrial waste treatment and soil remediation.•New ways to encourage, support, and implement optimal corrosion control practices.
Over the last century, electrochemical engineering has contributed significantly to societal progress by enabling development of industrial processes for manufacturing chemicals, such as chlorine and the Nylon precursor adiponitrile, as well as a wide range of metals including aluminium and zinc. In 2011, ca. 17 M tonne Cu p.a. was electro-refined to 99.99%+ purity required by electrical and electronic engineering applications, such as for electrodepositing with exquisite resolution multi-layer inter-connections in microprocessors. Surface engineering is widely practised industrially e.g. to protect steels against corrosion e.g. by electroplating nickel or using more recent novel self-healing coatings. Complex shapes of hard alloys that are difficult to machine can be fabricated by selective dissolution in electrochemical machining processes. Electric fields can be used to drive desalination of brackish water for urban supplies and irrigation by electrodialysis with ion-permeable membranes; such fields can also be used in electrokinetic soil remediation processes. Rising concerns about the consequences of CO2 emissions has led to the rapidly increasing development and deployment of renewable energy systems, the intermittency of which can be mitigated by energy storage in e.g. redox flow batteries for stationary storage and novel lithium batteries with increased specific energies for powering electric vehicles, or when economically viable, in electrolyser-fuel cells. The interface between electrochemical technology and biotechnology is also developing rapidly, with applications such as microbial fuel cells.
Some of these applications are reviewed, the challenges assessed and current trends elucidated in the very active area of Chemical Engineering bordering with material science and electrochemistry.
The COVID-19 pandemic has brought about changes in the management of urology patients, especially those with prostate cancer.
The aim of this work is to show the changes in the ambulatory care ...practices by individualized telematic care for each patient profile.
Articles published from March 2020 to January 2021 were reviewed. We selected those that provided the highest levels of evidence regarding risk in different aspects: screening, diagnosis, treatment and follow-up of prostate cancer.
We developed a classification system based on priorities, at different stages of the disease (screening, diagnosis, treatment and follow-up) to which the type of care given, in-person or telephone visits, was adapted. We established 4 options, as follows: in priority A or low, care will be given by telephone in all cases; in priority B or intermediate, if patients are considered subsidiary of an in-person visit after telephone consultation, they will be scheduled within 3 months; in priority C or high, patients will be seen in person within a margin from 1 to 3 months and in priority D or very high, patients must always be seen in person within a margin of up to 48 h and considered very preferential.
Telematic care in prostate cancer offers an opportunity to develop new performance and follow-up protocols, which should be thoroughly analyzed in future studies, in order to create a safe environment and guarantee oncologic outcomes for patients.
La pandemia por COVID-19 ha supuesto un cambio en la atención a pacientes en el ámbito urológico, especialmente con cáncer de próstata.
El objetivo de este trabajo es mostrar los cambios en el manejo a nivel ambulatorio individualizando para cada perfil de paciente la atención telemática.
Se han revisado artículos publicados desde marzo del 2020 hasta enero del 2021. Se han seleccionado aquellos que aportaban los mayores niveles de evidencia en cuanto al riesgo en distintos aspectos: cribado, diagnóstico, tratamiento y seguimiento del cáncer de próstata.
Desarrollamos una clasificación según prioridades, en diferentes etapas de la enfermedad (cribado, diagnóstico, tratamiento y seguimiento) adaptando a esta el tipo de control: presencial o telefónico. Establecemos 4 opciones: prioridad A o baja, en la que la atención será telefónica en todos los casos; prioridad B o intermedia, en la que si el paciente valorado telefónicamente se considera subsidiario de visita presencial, esta se citará dentro de los 3 meses posteriores; prioridad C o alta, el paciente será visto presencial con un margen para la visita de 1 a 3 meses, y prioridad D o muy alta, la visita deberá ser siempre presencial con un margen de hasta 48 h y considerada muy preferente.
La atención telemática en cáncer de próstata representa una oportunidad para desarrollar nuevos protocolos de actuación y seguimiento que deberán ser analizados exhaustivamente en futuros trabajos con el fin de conformar un entorno seguro y garantizar resultados oncológicos para los pacientes.
We present a new catalog of TeV gamma-ray sources using 1523 days of data from the High-Altitude Water Cherenkov (HAWC) Observatory. The catalog represents the most sensitive survey of the northern ...gamma-ray sky at energies above several TeV, with three times the exposure compared to the previous HAWC catalog, 2HWC. We report 65 sources detected at ≥5 significance, along with the positions and spectral fits for each source. The catalog contains eight sources that have no counterpart in the 2HWC catalog, but are within 1° of previously detected TeV emitters, and 20 sources that are more than 1° away from any previously detected TeV source. Of these 20 new sources, 14 have a potential counterpart in the fourth Fermi Large Area Telescope catalog of gamma-ray sources. We also explore potential associations of 3HWC sources with pulsars in the Australia Telescope National Facility (ATNF) pulsar catalog and supernova remnants in the Galactic supernova remnant catalog.
Large Cr, V and Ni contents were found in soils near Cd. Pemex in Tabasco, Mexico. Their origin was hypothesized to be either anthropogenic, derived from emissions of a petrochemical facility, or ...lithogenic, from the volcanic ash deposited by the “El Chichon” volcano, or accumulated residually by pedogenesis. We proved these possible origins by analyzing composite samples taken from the soil surface at different distances from the facility as well as samples from two soil profiles located close and far away from the facility within the same land unit, i.e. Acrisols developed on Miocene marine terraces. The sites located far away from the facility were closer to the volcano, and therefore supposedly more affected by the ash deposition. All samples were analyzed for their total metal content and profile samples for their different metal fractions. Additionally the soil microstructure, mineralogy and elemental composition of particular pedogenic features were studied in thin sections from the different soil horizons.
Results evidenced that the emissions from the petrochemical facility do not contribute significantly to the total concentration of Cr, Ni and V in the adjacent soils. Nickel was found in the soil in concentrations between 39 and 318mgkg−1; particularly large contents of this element were associated to volcanic ash additions visualized in the thin sections. Micromorphological analyses of nodule like pebbles found in both profiles evidenced that these features are laterite fragments transported from preexisting soil. The matrix of these fragments is enriched with Cr and V (3000–7000mgkg−1 of Cr, and 1000–3000mgkg−1V), and these elements are actually translocated into relatively newly formed iron concretions found within these laterites and reaching concentrations of up to 10,000–17,000mgkg−1 Cr.
The fractionation showed that Cr and V were dominantly associated to crystalline iron oxides and to the residual fraction; water extractable, exchangeable and EDTA extractable fractions were below detection limits (<2mgkg−1). Only Ni was extractable with NH4-acetate in the profile affected by volcanic ash in concentrations between 3.4 and 6.3mgkg−1.
We conclude that the studied elements are of lithogenic and pedogenic origin; they were enriched dominantly through residual accumulation by lateritization, probably of mesozoic ultramafic rocks from the margins of the Caribbean plate, and later fragmented and transported by water to the present location; only Ni was also partly added by the recent volcanic activity.
► Water transported laterite fragments from pedorelicts are responsible for the large Cr, V and Ni contents in the studied soils. ► Nearby El Chichón volcano contributed also to the Ni contents. ► Petroleum processing activities have not contributed significantly to the observed metal contents.
Background: The current flourishing of the specialty coffee market has motivated the development of this research on the basis that the harvested coffee fruits are a determining factor in drink ...quality. Objectives: The aim of this study was to evaluate the effect of the composition of harvested coffee (Coffea arabica L.) regarding the organoleptic quality of the coffee drink for the varieties Caturra and Colombia. Methods: Treatments for the assessed varieties were defined with different percentage compositions of coffee fruits M1 (100R), M2 (80R, 13OV, 7SR), M3 (60R, 26OV, 12SR, 2UR) and the control M4, which included fruits in different ripening stages, ripe (R), overripe (OV), semi-ripe (SR) and unripe (UR), in different proportions in experimental units of 10 kg of harvested coffee. The experimental design envisaged 3 rounds (repetitions) of harvest. The harvested coffee was classified manually according to its ripening stage using a previously developed scale based on colorimetry and recording the degrees Brix of 50 fruits in each ripening stage. The standardized wet processing method was carried out; a Q Grader cupping panel of five members was used for the sensory analysis of the coffee drink. Results: The results showed that for the variety Caturra statistical differences in cup quality between treatments were not found, whereas for the variety Colombia, treatments M1 and M3 showed similar behavior, with statistically significant differences regarding M2 and M4. Finally, the mathematical modeling obtained to predict the cup score depending on the coffee ripening stages composition, counted with coefficients of determination R2 of 0.833 and 0.852 with an error of 1.85 and 1.03% for the varieties Caturra and Colombia, respectively. Conclusions: The model developed with fuzzy logic and validated with information from other farms, presented an error of less than 2% in the estimation of the cup as a function of the ripening stages composition of the coffee varieties Caturra and Colombia.
Cribriform adenocarcinoma of salivary gland (CASG) is a rare, salivary gland tumor. In this report, we describe a case of CASG harboring a novel PPP2R2A::PRKD1 fusion. A 58‐year‐old female presented ...with an intraoral mass adjacent to the lower left third molar region. Morphological features at histological examination, immunohistochemical staining (p63+, p40−), and tumor location were indicative of CASG. However, due to the potential focal presence of a biphasic component within the tumor, RNA sequencing was performed to confirm the diagnosis. The subsequently found novel PPP2R2A::PRKD1 fusion adds to the rapidly evolving molecular landscape of salivary gland tumors. Additionally, we report that CASG may show some entrapment of pre‐existent salivary gland ducts, which may be misinterpreted as tumor cells with myoepithelial differentiation.
INTRODUCTIONNew imaging studies have appeared in recent years for the diagnosis and follow-up of metastatic urological tumours. MATERIAL AND METHODSA total of 41 patients were reviewed with suspected ...recurrence of a urothelial or kidney tumour, analysing the diagnostic performance of PET-CT scans undertaken between 2013 and 2016. RESULTSWe collected 17 urothelial tumours and 24 renal tumours, with a median follow-up of 30 months. A total of 39.3% of the urothelial tumours were high grade and 29.3% of the kidney tumours were clear cell Fuhrman II. As a whole, the imaging studies detected recurrences in 34 patients. CT was positive in 83% of the patients, while the PET scan was positive in 75.6%, CT/PET coincidence was 50%. The PET scan detected further disease in 41% of the cases compared to 5% by CT. This resulted in a change of therapeutic strategy in 40% of the patients. Sensitivity, specificity, positive predictive value and negative predictive value for the CT and the PET scans were 92% and 92%, 57% and 100%, 92% and 100%, and 57% and 70% respectively. CONCLUSIONThe PET scan showed similar sensitivity for urological tumours to the standard imaging techniques but with higher specificity, positive predictive value and negative predictive value. This led to a change in treatment strategy for 40% of the patients in our series. The PET scan will probably become the standard test in the extension and follow-up studies of most urological tumours.
Early identification of learning difficulties is a critical component of the Response to Intervention (RtI) model. In kindergarten, the screening of foundational reading skills can provide a ...data-based guideline for identifying students requiring a more intensive response-based intervention before starting elementary school. This study examines the classification accuracy and best predictors of a set of Spanish curriculum-based measures administered during kindergarten. The study’s sample included 189 students tested in the fall, winter, and spring. Receiver operating characteristic (ROC) analysis was conducted. The composite score of the curriculum-based measurement (CBM) revealed area under the ROC curve (AUC) values of 0.83, 0.97, and 0.94 in the fall, winter, and spring, respectively. Phonemic awareness and letter-sound knowledge were the only isolated measures that demonstrated excellent AUC values throughout kindergarten. Logistic regression models showed that, when entered simultaneously, all measures were significant predictors of reading risk at some moment of the school year.
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