Cinética de la reducción carbotérmica de la calcopirita del Complejo Marañón

Taking the Peru a leadership in the production of metals in the world, the world’s largest producer of silver, the second of copper and zinc, and the sixth in gold, it is necessary to develop intensive metallurgical research to give greater technological value to our concentrates. In the framework of clean technologies direct reduction of sulphides is of interest in metallurgical processes for obtaining base metal. In this investigation shows results of the kinetics of direct reduction of the chalcopyrite of complex marañón with coal in the presence of dolomite as an opportunity to produce copper from a sulphide avoiding air pollution. We studied the effect of the variables involved in the reduction carbotermica: Temperature, reasons molars of reactants, being kinetic model that we describe the phenomenology of reduction process of the chalcopyrite.Teniendo el Perú un liderazgo en la producción de metales en el mundo, el mayor productor mundial de plata, el segundo de cobre y zinc, y el sexto en oro, es preciso desarrollar intensivas investigaciones metalúrgicas para dar mayor valor tecnológico a nuestros concentrados. En el marco de las tecnologías limpias la reducción directa de sulfuros es de interés en los procesos metalúrgicos para la obtención de metal base. En la presente investigación se muestra resultados de la cinética de reducción directa de la calcopirita del complejo marañón con carbón en presencia de dolomita como una posibilidad de producir cobre a partir de un sulfuro evitando la contaminación atmosférica. Se estudiaron el efecto de las variables involucradas en la reducción carbotérmica: Temperatura, razones molares de los reactantes, encontrándose modelos cinéticos que nos describen la fenomenología del proceso de reducción de la calcopirita

The photochemical mediated ring contraction of 4H-1,2,6-thiadiazines to afford 1,2,5-thiadiazol-3(2H)-one 1-oxides

E.B. and C.G.T. are grateful to Heriot-Watt University and the EPSRC CRITICAT Centre for Doctoral Training (E.B. Ph.D. Studentship: EP/L016419/1, C.G.T Ph.D. Studentship: EP/LO14419/1) for funding and training. C.G.T. is grateful to the Heriot-Watt Annual Fund for financial support. P.A.K. and A.S.K. thank the University of Cyprus for the Internal Grant “Thiadiazine-Based Organic Photovoltaics”, and the Cyprus Research Promotion Foundation (Grant Nos. ΣΤΡΑΤΗΙΙ/0308/06, NEKYP/0308/02 ΥΓΕΙΑ/0506/19, and ΕΝΙΣΧ/0308/83). M.J.P. thanks the EPSRC for funding (Grant Nos. EP/T021675 and EP/V006746), and the Leverhulme Trust (Grant No. PG-2020-208). S.A.M. thanks the EPSRC for funding (Grant No. EP/T019867/1).1,2,6-Thiadiazines treated with visible light and 3O2 under ambient conditions are converted into difficult-to-access 1,2,5-thiadiazole 1-oxides (35 examples, yields of 39–100%). Experimental and theoretical studies reveal that 1,2,6-thiadiazines act as triplet photosensitizers that produce 1O2 and then undergo a chemoselective [3 + 2] cycloaddition to give an endoperoxide that ring contracts with selective carbon atom excision and complete atom economy. The reaction was optimized under both batch and continuous-flow conditions and is also efficient in green solvents.Publisher PDFPeer reviewe

Presence-Absence Sampling Plans for Stink Bugs (Hemiptera: Pentatomidae) in the Midwest Region of the United States

Stink bugs represent an increasing risk to soybean production in the Midwest region of the United States. The current sampling protocol for stink bugs in this region is tailored for population density estimation and thus is more relevant to research purposes. A practical decision-making framework with more efficient sampling effort for management of herbivorous stink bugs is needed. Therefore, a binomial sequential sampling plan was developed for herbivorous stink bugs in the Midwest region. A total of 146 soybean fields were sampled across 11 states using sweep nets in 2016, 2017, and 2018. The binomial sequential sampling plans were developed using combinations of five tally thresholds at two proportion infested action thresholds to identify those that provided the best sampling outcomes. Final assessment of the operating characteristic curves for each plan indicated that a tally threshold of 3 stink bugs per 25 sweeps, and proportion infested action thresholds of 0.75 and 0.95 corresponding to the action thresholds of 5 and 10 stink bugs per 25 sweeps, provided the optimal balance between highest probability of correct decisions (≥ 99%) and lowest probability of incorrect decisions (≤ 1%). In addition, the average sample size for both plans (18 and 12 sets of 25 sweeps, respectively) was lower than that for the other proposed plans. The binomial sequential sampling plan can reduce the number of sample units required to achieve a management decision, which is important because it can potentially reduce risk/cost of management for stink bugs in soybean in this region

Comportamiento de los iones metálicos lixiviados en la cementación del cobre

This article describes the cementation process of leached solutions from copper sulphide ores being and without being toasted. With favorable results in this study, we get the pattern for the feasibility of moving from the classical technology of concentration to the technology of cementation of copper sulfide minerals containing silver and gold. Simulation steps have been performed considering the different variables involved in the process such as time, agitation, solution concentration, pH and others. A kinetic model of copper cementation from PLS solutions purified by Solvent Extraction (SX) has been developed and it has the following form: C = 6.08 exp (- 0.03 t) Recoveries were obtained greater than 90% copper, which gives the possibility to improve the costs of national ores and con- centrates, as well as to open a favorable scenario for new national metallurgical projects.El presente artículo trata de describir la cementación de soluciones lixiviadas de minerales sulfurados de cobre sin tostar y tostados, obteniéndose resultados favorables lo que nos dan la pauta para la factibilidad de pasar de la clasica tecnología de concentración a la tecnología de cementación de minerales sulfurados de cobre con buenos tenores de plata y oro. Se ha procedido a realizar simulaciones del proceso considerando las variables involucradas en el proceso, tales como tiempo, agitación, concentración de soluciones, pH entre otros. El Modelo Cinético de Cementación del Cobre a partir de soluciones PLS purificadas por Extracción por Solventes (SX) encontrado tiene la siguiente configuración: C = 6,08 exp( - 0,03t) Se han obtenido recuperaciones mayores del 90% de cobre, lo cual nos indica la posibilidad de mejorar los costos de los minerales y concentrados nacionales y abrir un escenario favorable para otros proyectos metalúrgicos nacionales

Transporters in Drug Development: 2018 ITC Recommendations for Transporters of Emerging Clinical Importance

This white paper provides updated International Transporter Consortium (ITC) recommendations on transporters that are important in drug development following the 3rd ITC workshop. New additions include prospective evaluation of organic cation transporter 1 (OCT1) and retrospective evaluation of organic anion transporting polypeptide (OATP)2B1 because of their important roles in drug absorption, disposition, and effects. For the first time, the ITC underscores the importance of transporters involved in drug-induced vitamin deficiency (THTR2) and those involved in the disposition of biomarkers of organ function (OAT2 and bile acid transporters)

Day-and-night glycaemic control with closed-loop insulin delivery versus conventional insulin pump therapy in free-living adults with well controlled type 1 diabetes: an open-label, randomised, crossover study.

BACKGROUND: Tight control of blood glucose concentration in people with type 1 diabetes predisposes to hypoglycaemia. We aimed to investigate whether day-and-night hybrid closed-loop insulin delivery can improve glucose control while alleviating the risk of hypoglycaemia in adults with HbA1c below 7·5% (58 mmol/mol). METHODS: In this open-label, randomised, crossover study, we recruited adults (aged ≥18 years) with type 1 diabetes and HbA1c below 7·5% from Addenbrooke's Hospital (Cambridge, UK) and Medical University of Graz (Graz, Austria). After a 2-4 week run-in period, participants were randomly assigned (1:1), using web-based randomly permuted blocks of four, to receive insulin via the day-and-night hybrid closed-loop system or usual pump therapy for 4 weeks, followed by a 2-4 week washout period and then the other intervention for 4 weeks. Treatment interventions were unsupervised and done under free-living conditions. During the closed-loop period, a model-predictive control algorithm directed insulin delivery, and prandial insulin delivery was calculated with a standard bolus wizard. The primary outcome was the proportion of time when sensor glucose concentration was in target range (3·9-10·0 mmol/L) over the 4 week study period. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT02727231, and is completed. FINDINGS: Between March 21 and June 24, 2016, we recruited 31 participants, of whom 29 were randomised. One participant withdrew during the first closed-loop period because of dissatisfaction with study devices and glucose control. The proportion of time when sensor glucose concentration was in target range was 10·5 percentage points higher (95% CI 7·6-13·4; p<0·0001) during closed-loop delivery compared with usual pump therapy (65·6% [SD 8·1] when participants used usual pump therapy vs 76·2% [6·4] when they used closed-loop). Compared with usual pump therapy, closed-loop delivery also reduced the proportion of time spent in hypoglycaemia: the proportion of time with glucose concentration below 3·5 mmol/L was reduced by 65% (53-74, p<0·0001) and below 2·8 mmol/L by 76% (59-86, p<0·0001). No episodes of serious hypoglycaemia or other serious adverse events occurred. INTERPRETATION: Use of day-and-night hybrid closed-loop insulin delivery under unsupervised, free-living conditions for 4 weeks in adults with type 1 diabetes and HbA1c below 7·5% is safe and well tolerated, improves glucose control, and reduces hypoglycaemia burden. Larger and longer studies are warranted. FUNDING: Swiss National Science Foundation (P1BEP3_165297), JDRF, UK National Institute for Health Research Cambridge Biomedical Research Centre, and Wellcome Strategic Award (100574/Z/12/Z)

Time spent in hypoglycemia according to age and time-of-day: Observations during closed-loop insulin delivery.

OBJECTIVE We aimed to assess whether percentage of time spent in hypoglycemia during closed-loop insulin delivery differs by age-group and time-of-day. METHODS We retrospectively analyzed data from hybrid closed-loop studies involving young children (2-7 years), children and adolescents (8-18 years), adults (19-59 years), and older adults (≥60 years) with type 1 diabetes. Main outcome was time spent in hypoglycemia <3.9mmol/l. Eight weeks of data for 88 participants were analyzed. RESULTS Median time spent in hypoglycemia over the 24-hour period was highest in children and adolescents (4.4%; [IQR 2.4-5.0]) and very young children (4.0% [3.4-5.2]), followed by adults (2.7% [1.7-4.0]), and older adults (1.8% [1.2-2.2]); p<0.001 for difference between age-groups. Time spent in hypoglycemia during nighttime (midnight-05:59) was lower than during daytime (06:00-23:59) across all age-groups. CONCLUSION Time in hypoglycemia was highest in the pediatric age-group during closed-loop insulin delivery. Hypoglycemia burden was lowest overnight across all age-groups

Introduction to Special Issue - In-depth study of air pollution sources and processes within Beijing and its surrounding region (APHH-2 Beijing)

Abstract. The Atmospheric Pollution and Human Health in a Chinese Megacity (APHH-Beijing) programme is an international collaborative project focusing on understanding the sources, processes and health effects of air pollution in the Beijing megacity. APHH-Beijing brings together leading China and UK research groups, state-of-the-art infrastructure and air quality models to work on four research themes: (1) sources and emissions of air pollutants; (2) atmospheric processes affecting urban air pollution; (3) air pollution exposure and health impacts; and (4) interventions and solutions. Themes 1 and 2 are closely integrated and support Theme 3, while Themes 1-3 provide scientific data for Theme 4 to develop cost-effective air pollution mitigation solutions. This paper provides an introduction to (i) the rationale of the APHH-Beijing programme, and (ii) the measurement and modelling activities performed as part of it. In addition, this paper introduces the meteorology and air quality conditions during two joint intensive field campaigns - a core integration activity in APHH-Beijing. The coordinated campaigns provided observations of the atmospheric chemistry and physics at two sites: (i) the Institute of Atmospheric Physics in central Beijing, and (ii) Pinggu in rural Beijing during 10 November – 10 December 2016 (winter) and 21 May- 22 June 2017 (summer). The campaigns were complemented by numerical modelling and automatic air quality and low-cost sensor observations in the Beijing megacity. In summary, the paper provides background information on the APHH-Beijing programme, and sets the scene for more focussed papers addressing specific aspects, processes and effects of air pollution in Beijing