Síntesis de óxido de grafito, dopaje con aminas aromáticas y su posterior reducción. Caracterización de los compuestos obtenidos

El objetivo del presente trabajo es la síntesis de óxido de grafito (OG) por el método de Hummers modificado y su posterior funcionalización con las aminas: o-fenilen-diamina (oPDA) y con la tetraamina 3,3’-diaminobencidina(TABNCD). El óxido de grafito dopado con las aminas dio lugar a OG-oPDA y OG-TABNCD; posterior- mente el OG y los dopados se redujeron utilizando borohidruro de sodio(BHS). El dopaje de OG con oPDA y TABNCD se realizó con exceso de ácido polifosfórico (APF) y el último se llevó a cabo con calentamiento en etapas. La reducción de OG-TABNCD con BHS se llevó a cabo en 3 lotes con cantidades distintas. Los materiales obtenidos fueron caracterizados por Espectroscopía IR, RAMAN, Difracción de Rayos X(DRX), Análisis Termogravimétrico (TGA), Fisisorción de nitrógeno (Áreas BET) y Microscopía Electrónica de Barrido (SEM).The present work concerns the synthesis of graphite oxide (GO) based on the modified Hummers method, the functionalization of GO was carried out with the amines: o-phenylenediamine (oPDA) and the tetraamine 3,3’-diaminobenzidine (TABNCD). The doped GO produces GO-oPDA and GO-TABNCD respectively. Thereafter OG, GO-oPDA and GO-TABNCD were reduced with sodium borohydride (SBH). The doping of GO with oPDA and TABNCD was performed with polyphosphoric acid (PPA) in excess and in the case of TABNCD this was carried out by means of a progressive heating. The reduction of GO-TABNCD was performed in three different batches. All obtained materials were subjected to spectroscopic analyses of IR, RAMAN, X ray diffraction (DRX), Termogravimetric analysis (TGA), Nitrogen fisisortion (BET area) and Scaning electronic microscopy (SEM)

Evaluation of the Loading, Unloading, and Permanent Deformation of Newly Available Epoxy Resin Coated Ni-Ti Wires Using Self-Ligating Brackets

Aim. The purpose of this study was to evaluate the load and unload deflection and permanent deformation of round 0.016′′ and rectangular 0.016′′×0.022′′ regular and coated Ni-Ti wires. Materials and Methods. Ni-Ti archwires produced by two manufacturers were evaluated. Both regular and coated round and rectangular Ni-Ti wire segments (n=15) from each group were submitted to a three-point bending test. Both types of wires were evaluated for permanent deformation at the end of a recovery cycle. Results. The coated round 0.016′′ Ni-Ti wires produced a significantly lower force in loading (p<0.01) and unloading (p<0.01) than regular wires of the same manufacturer and size. There was no significant difference in permanent deformation between coated and regular round Ni-Ti wires from the same company. For rectangular 0.016×0.022′′ Ni-Ti wires, there was a significant difference in the loading evaluation, but the unloading test presented no significant differences. The permanent deformation of the rectangular wires revealed no significant difference between them. Conclusion. The addition of an esthetic coating to these new Ni-Ti wires produced changes in their mechanical properties, manifested as a reduction in the applied force, which should be considered in clinical management

Melanocortin-1 Receptor, Skin Cancer and Phenotypic Characteristics (M-SKIP) Project: Study Design and Methods for Pooling Results of Genetic Epidemiological Studies

Background: For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia. Design and methods: Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling. Discussion: Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields

Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p&lt;0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (&lt;1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (&lt;1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

The Helicobacter pylori Genome Project : insights into H. pylori population structure from analysis of a worldwide collection of complete genomes

Helicobacter pylori, a dominant member of the gastric microbiota, shares co-evolutionary history with humans. This has led to the development of genetically distinct H. pylori subpopulations associated with the geographic origin of the host and with differential gastric disease risk. Here, we provide insights into H. pylori population structure as a part of the Helicobacter pylori Genome Project (HpGP), a multi-disciplinary initiative aimed at elucidating H. pylori pathogenesis and identifying new therapeutic targets. We collected 1011 well-characterized clinical strains from 50 countries and generated high-quality genome sequences. We analysed core genome diversity and population structure of the HpGP dataset and 255 worldwide reference genomes to outline the ancestral contribution to Eurasian, African, and American populations. We found evidence of substantial contribution of population hpNorthAsia and subpopulation hspUral in Northern European H. pylori. The genomes of H. pylori isolated from northern and southern Indigenous Americans differed in that bacteria isolated in northern Indigenous communities were more similar to North Asian H. pylori while the southern had higher relatedness to hpEastAsia. Notably, we also found a highly clonal yet geographically dispersed North American subpopulation, which is negative for the cag pathogenicity island, and present in 7% of sequenced US genomes. We expect the HpGP dataset and the corresponding strains to become a major asset for H. pylori genomics

Propuesta de optimización para el proceso de fabricación de un producto culinario para la reducción de merma, en una industria alimenticia

Proponer la optimización del proceso de fabricación del producto culinario para la reducción de merma, así aumentar la eficiencia del proceso al minimizar la merma generada con la finalidad de elevar la productividad de la empresa

Annotated checklist of amphibians and reptiles from&amp;nbsp;Quer&amp;eacute;taro, Mexico, including new records, and comments on controversial species

We present an updated checklist of amphibians and reptiles of Quer&amp;eacute;taro, Mexico. The herpetofauna of Quer&amp;eacute;taro is composed of 136 species, 35 amphibians (seven caudates and 28 anurans) grouped in nine families and 20 genera; 101 reptiles (five turtles, 33 lizards, and 63 snakes) grouped in 20 families and 59 genera. We did not include 13 previous records that do not have adequate evidence. We include three newly reported species for Quer&amp;eacute;taro: Coniophanes imperialis (Baird &amp;amp; Girard, 1859), Scaphiodontophis annulatus (Dum&amp;eacute;ril, Bibron &amp;amp; Dum&amp;eacute;ril, 1854), and Xenosaurus newmanorum (Taylor, 1949). A total of 69 species (51% of the total species) are endemic to Mexico, while one species, Sceloporus exsul (Dixon, Ketchersid &amp;amp; Lieb, 1972), is endemic to the state. According to Mexican law (SEMARNAT NOM-059), 50 species are threatened or under special protection, while according to the IUCN red list, only 11 species are under some category of risk. We suggest that a greater survey effort for amphibians and reptiles is required to discover unrecorded species in those areas that have not been sufficiently sampled

Experimental Study on the Performance of Controllers for the Hydrogen Gas Production Demanded by an Internal Combustion Engine

This work presents the design and application of two control techniques&mdash;a model predictive control (MPC) and a proportional integral derivative control (PID), both in combination with a multilayer perceptron neural network&mdash;to produce hydrogen gas on-demand, in order to use it as an additive in a spark ignition internal combustion engine. For the design of the controllers, a control-oriented model, identified with the Hammerstein technique, was used. For the implementation of both controllers, only 1% of the overall air entering through the throttle valve reacted with hydrogen gas, allowing maintenance of the hydrogen&ndash;air stoichiometric ratio at 34.3 and the air&ndash;gasoline ratio at 14.6. Experimental results showed that the average settling time of the MPC controller was 1 s faster than the settling time of the PID controller. Additionally, MPC presented better reference tracking, error rates and standard deviation of 1.03 &times; 10 &minus; 7 and 1.06 &times; 10 &minus; 14 , and had a greater insensitivity to measurement noise, resulting in greater robustness to disturbances. Finally, with the use of hydrogen as an additive to gasoline, there was an improvement in thermal and combustion efficiency of 4% and 0.6%, respectively, and an increase in power of 545 W, translating into a reduction of fossil fuel use

Hospital Municipal de Zona Bananera

Hoy en día es de gran importancia para la sociedad contar con buena infraestructura en el sector de la salud, con la finalidad de garantizar de forma eficiente este derecho fundamental. En el departamento del Magdalena (Colombia) se ha presentado desde hace muchos años una situación insostenible en este sentido, debido a que hay graves deficiencias en los servicios hospitalarios. La infraestructura se encuentra en precarias condiciones, se presentan elevadas cifras de remisión de pacientes y además con la reciente pandemia debido al COVID-19 se han evidenciado todas estas falencias. Dicha problemática se agrava en el municipio de Zona Bananera. De esta manera, se hace pertinente la formulación del proyecto “Hospital Municipal de Zona Bananera”, el cual contará con los diversos servicios hospitalarios y especialidades que ofrece un hospital de segundo nivel. Este proyecto contará con un edificio principal de cuatro niveles (incluyendo el sótano), un pabellón de urgencias, parqueaderos, zona de recolección de residuos, zonas verdes, planta de tratamiento de aguas residuales y sus respectivas vías de acceso; impactando así la calidad de vida de la población local y departamental. Con este proyecto, se contemplan todos los estudios de prefactibilidad y sus respectivos diseños arquitectónicos e ingenieriles previos a la construcción del Hospital tales como: estudios geotécnicos, diseño de cimentaciones y estructura del edificio principal, redes hidrosanitarias, estudios del tránsito, diseño de vías y de pavimento. Cabe resaltar que en dichos estudios se presentaron obstáculos debido a la falta de información. Sin embargo, se lograron realizar las estimaciones pertinentes al caso cumpliendo todos los requerimientos técnicos de la normativa vigente en Colombia. Finalmente, se lograron obtener los diseños pertinentes de la infraestructura planteada con la cual se prevé que posee el potencial de solucionar la problemática en cuestión.Today it is of great importance for society to have a good infrastructure in the health sector, in order to efficiently guarantee this fundamental right. In the department of Magdalena (Colombia) an unsustainable situation in this sense has been presented for many years, due to the fact that there are serious deficiencies in hospital services, the infrastructure is in precarious conditions, there are high numbers of patient referrals. Furthermore, with the recent pandemic due to COVID-19, all these shortcomings have been evidenced. This problem is aggravated in the municipality of Zona Bananera. In this way, the formulation of the project "Hospital Municipal de Zona Bananera" becomes pertinent, which will have the various hospital services and specialties offered by a second-level hospital. This project will have a main building with four levels (including the basement), an emergency pavilion, parking lots, waste collection area, green areas, wastewater treatment plant and their respective access roads; thus impacting the quality of life of the local and departmental population. With this project, all the pre-feasibility studies and their respective architectural and engineering designs prior to the construction of the Hospital are contemplated, such as: geotechnical studies, design of foundations and structure of the main building, hydrosanitary networks, traffic studies, design of roads and of pavement. It should be noted that these studies presented obstacles due to the lack of information. However, it was possible to make the pertinent estimates for the case, complying with all the technical requirements of the regulations in force in Colombia. Finally, it was possible to obtain the pertinent designs of the proposed infrastructure with which it is expected that it has the potential to solve the problem in question