Zeolitization of Diatomite Residues by a Simple Method

Abstract The possibility of transforming a diatomite-rich waste from the brewing industry into synthetic zeolites has been investigated. After precalcination at 550 °C to eliminate the retained organic matter, the clean diatomite (Dt; with a Si/Al molar ratio of 17.4), was hydrothermally treated for 24 h with continuous stirring in a 3M NaOH solution at 80 °C. The results of mineralogical characterization by X-ray diffraction with Rietveld refinement have shown a crystallization of 55% of zeolite P, which was neoformed from the amorphous phase, opal-CT and quartz of the starting sample. The spectra obtained by Fourier Transform Infrared Spectrometry have corroborated such zeolitization. N2 adsorption–desorption isotherms have shown that the zeolitized material (Dt-Z) is mesoporous, with almost 60% more specific surface area than Dt (62.6 m2/g vs. 39.4 m2/g), greater microporosity and 40% smaller average pore size than Dt (71 Å vs. 118 Å). This study is a first approximation to know the potential of diatomite wastes as zeolite precursors, for which additional research including an aluminum source will be required.This research was conducted as a part of the ECO-MET-AL Project, PID2019-109520RB-I00/AEI/10.13039/501100011033, “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a “Proyectos I+D+i” en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I+D+i y de I+D+i orientada a los Retos de la Sociedad, Convocatoria 2019”. Thanks also to the SCAI of the University of Jaén, the University of Castilla-La Mancha and the University of Málaga for their services. The authors also acknowledge the Postdoctoral Contract granted through the Resolution of 21 May 2020, of the General Secretariat for Universities, Research and Technology of the Government of Andalusia (Spain) within the scope of the Andalusian Plan for Research, Development and Innovation (PAIDI 2020)

Riesgos de adaptación en franquicias: herramientas de contabilidad de gestión para mitigarlos

El crecimiento sostenido del mercado de franquicias en países desarrollados, impulsa su afianzamiento en mercados emergentes. En Colombia se han establecido más de 500 marcas de este formato empresarial y, sin embargo, la documentación estadística o académica que describa la adaptación de este tipo de empresas en el país y sus procesos de internacionalización son escasos. Como una contribución al acervo académico y a la comprensión de este fenómeno, el presente artículo es un estudio de tres casos exploratorios que tiene como objetivo identificar los riesgos de adaptación de franquicias dedicadas a la prestación servicios de formación extracurricular para niños en Colombia. Las entrevistas fueron realizadas a los líderes responsables del proceso de expansión de la franquicia en Colombia. Los riesgos de adaptación identificados se agruparon en desarrollo comercial y animación de la red, los cuales evidencian, perfiles inadecuados en la selección de franquiciados, afectación de la marca, poco estudio de la competencia y problemas de comunicación y seguimiento

Comparative Life Cycle Assessment of Lightweight Aggregates Made from Waste—Applying the Circular Economy

Abstract The application of Life Cycle Assessment in the construction sector can be a very useful tool to reduce the environmental impact generated by the sector. In order to quantify the improvement in environmental terms with the use of artificial lightweight aggregates (LWA) manufactured with waste, in this work, we conducted a comparative evaluation of the life cycle of LWAs for a total of five different scenarios: LWAs obtained in a traditional way, i.e., using exclusively clay in their manufacture (Spanish blond clay, Portuguese red clay and Portuguese blond clay), and LWAs manufactured with four different wastes, with a partial substitution of 2.5% for each of the clays per waste (almond and hazelnut shells, sludge from the purification of paper money, cork dust and coffee grounds). The functional unit was set as the production of 1 kilo of lightweight aggregates and the CML 2000 methodology and the SimaPro software were used. The results obtained in this research allow us to conclude that the addition of organic wastes showed a slightly higher environmental performance than the conventional system, the ALAs manufactured with almond and hazelnut shells being the most environmentally friendly option, with reductions of more than 30% in some cases, followed by the LWAs manufactured with coffee grounds. On the other hand, the addition of paper sewage sludge and cork dust represents minimal environmental optimization.This research was conducted as a part of the ECO-MET-AL Project (PID2019-109520RB-I00), “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a ‘Proyectos I + D + i’ en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I + D + i y de I + D + i orientada a los Retos de la Sociedad, Convocatoria 2019”. The authors also gratefully acknowledge the technical and human support provided by CICT of the University of Jaén and the University of Málaga (UJA, MINECO, Junta de Andalucía, FEDER)

Determinación del grado de satisfacción ciudadana acerca del transporte público vehicular en Valledupar, Cesar

El  deterioro  en  los  vehículos  de  transporte público  y  el  mal  servicio  que  estos  prestan han ocasionado que la ciudadanía opte por utilizar servicios de transporte que están en contra de las leyes,  como el mototaxismo y el uso indebido de taxis tomados como rutas de colectivos. El objetivo general de esta in- vestigación fue determinar el grado de sa- tisfacción ciudadana acerca del transporte público vehicular en la ciudad de Valledupar, Cesar. Para lograr el objetivo general se utili- zó la investigación de tipo descriptiva con un enfoque mixto, la cual se basó en encuestas a la comunidad universitaria y a la población que transita frecuentemente por el centro de la ciudad. Dentro de los resultados obtenidos se destaca el hecho de que la socialización de las nuevas rutas establecidas es deficiente, además de que el 61% de los encuestados no está de acuerdo con el valor exigido por la empresa prestadora del servicio. Se concluyó que el grado de satisfacción de la población de Valledupar con respecto a los vehículos de transporte público es bajo, puesto que el servicio que se presta no suple totalmente las necesidades de los usuario

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.

Analyzing the Role of Fe0 and Fe3+ in the Formation of Expanded Clay Aggregates

The effect of the addition of Fe0 and Fe3+ on the formation of expanded clay aggregates was studied using iron-free kaolin as an aluminosilicates source. Likewise, the incorporation of cork powder as a source of organic carbon and Na2CO3 as a flux in the mixtures was investigated in order to assess its effect in combination with the iron phases. An experimental protocol, statistically supported by a mixture experiments/design of experiments approach, was applied to model and optimize the bloating index, density, absorption capacity, and mechanical strength. The process of expansion and pore generation and the associated decrease in density required the addition of iron, such that the optimum mixtures of these properties presented between 25 and 40 wt.% of Fe0 or Fe3+, as well as the incorporation of 3.5–5 wt.% of organic carbon. The addition of Fe3+ produced a greater volumetric expansion (max. 53%) than Fe0 (max. 8%), suggesting that the formation of the FeO leading to this phenomenon would require reducing and oxidizing conditions in the former and the latter, respectively. The experimental and model-estimated results are in good agreement, especially in the aggregates containing Fe0. This reinforces the application of statistical methods for future investigations.Many thanks for Mark Tyrer (https://orcid.org/0000-0003-3327-895X, accessed on 20 June 2023) that help us to improve the english for our research work. This research was conducted as a part of the ECO-MET-AL Project, PID2019-109520RB-I00/AEI/10.13039/501100011033, “Can industrial and mining metalliferous wastes produce green lightweight aggregates? Applying the Circular Economy” funded by the Spanish Ministry of Science, Innovation and Universities and ERDF funds, framed in the “Ayudas a “Proyectos I+D+i” en el marco de los Programas Estatales de Generación de Conocimiento y Fortalecimiento Científico y Tecnológico del Sistema de I+D+i y de I+D+i orientada a los Retos de la Sociedad, Convocatoria 2019”. We also wish to thank the SCAI of the University of Jaén, the University of Castilla-La Mancha and the University of Málaga for their services

Effect of aliskiren on post-discharge outcomes among diabetic and non-diabetic patients hospitalized for heart failure: insights from the ASTRONAUT trial

Aims The objective of the Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was to determine whether aliskiren, a direct renin inhibitor, would improve post-discharge outcomes in patients with hospitalization for heart failure (HHF) with reduced ejection fraction. Pre-specified subgroup analyses suggested potential heterogeneity in post-discharge outcomes with aliskiren in patients with and without baseline diabetes mellitus (DM). Methods and results ASTRONAUT included 953 patients without DM (aliskiren 489; placebo 464) and 662 patients with DM (aliskiren 319; placebo 343) (as reported by study investigators). Study endpoints included the first occurrence of cardiovascular death or HHF within 6 and 12 months, all-cause death within 6 and 12 months, and change from baseline in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 1, 6, and 12 months. Data regarding risk of hyperkalaemia, renal impairment, and hypotension, and changes in additional serum biomarkers were collected. The effect of aliskiren on cardiovascular death or HHF within 6 months (primary endpoint) did not significantly differ by baseline DM status (P = 0.08 for interaction), but reached statistical significance at 12 months (non-DM: HR: 0.80, 95% CI: 0.64-0.99; DM: HR: 1.16, 95% CI: 0.91-1.47; P = 0.03 for interaction). Risk of 12-month all-cause death with aliskiren significantly differed by the presence of baseline DM (non-DM: HR: 0.69, 95% CI: 0.50-0.94; DM: HR: 1.64, 95% CI: 1.15-2.33; P < 0.01 for interaction). Among non-diabetics, aliskiren significantly reduced NT-proBNP through 6 months and plasma troponin I and aldosterone through 12 months, as compared to placebo. Among diabetic patients, aliskiren reduced plasma troponin I and aldosterone relative to placebo through 1 month only. There was a trend towards differing risk of post-baseline potassium ≥6 mmol/L with aliskiren by underlying DM status (non-DM: HR: 1.17, 95% CI: 0.71-1.93; DM: HR: 2.39, 95% CI: 1.30-4.42; P = 0.07 for interaction). Conclusion This pre-specified subgroup analysis from the ASTRONAUT trial generates the hypothesis that the addition of aliskiren to standard HHF therapy in non-diabetic patients is generally well-tolerated and improves post-discharge outcomes and biomarker profiles. In contrast, diabetic patients receiving aliskiren appear to have worse post-discharge outcomes. Future prospective investigations are needed to confirm potential benefits of renin inhibition in a large cohort of HHF patients without D