627 research outputs found

    Highly active P-doped sulfided NiMo/alumina HDS catalysts from Mo-blue by using saccharose as reducing agents precursor

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    Saccharose (SA) was used as organic additive in simultaneously impregnated P-doped NiMo/Al2O3 hydrodesulfurization (HDS) catalysts (Mo, Ni and P at 12, 3, and 1.6 wt%, respectively). One-pot impregnating solutions were prepared by MoO3 digestion (∼353 K) in diluted aqueous H3PO4, followed by 2NiCO3·3Ni (OH)2·4H2O addition. Saccharose (SA, SA/Ni=0.5, 1–3) was dissolved in originally emerald-green impregnating solutions which changed to cobalt blue by room-temperature aging (2–4 days, depending on SA concentration) due to Mo-blue formation by partial molybdenum species reduction. After sulfiding of samples impregnated with SA shorter MoS2 slabs of enhanced stacking were observed (by HR-TEM). Ni and Mo dispersion and nickel sulfidability (as determined by XPS) increased with the amount of organic modifier. Enhanced hydrodesulfurization activity in dibenzothiophene HDS was registered for catalyst obtained from Mo-blue precursor as to that of corresponding materials obtained from conventional emerald-green NiMoP impregnating solutions (with or without SA). However, in solids at high saccharose content (SA/Ni=3) enhanced “NiMoS” phase amount was not reflected in improved activity. Probably, excessive amount of carbonaceous deposits from SA residua decomposition during catalyst activation provoked partially plugged porous network (as determined by N2 physisorption) in sulfided formulations. That fact seemed to limit accessibility of reactant molecules to surface active sites. Mo-blue precursor obtained through monosaccharides partial reduction seemed to play decisive role in obtaining HDS catalysts of improved properties. Saccharose results a highly soluble, cheap and non-toxic environmentally-friendly additive to produce catalysts of enhanced HDS activity.The authors acknowledge support through 117086 SENERCONACYT-Hidrocarburos grant and Y.00105 Project from IMP. A.W. Gutiérrez thanks CONACYT for graduate student scholarship

    Los roles de género de los hombres y las mujeres en el México contemporáneo

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    Desde el nacimiento, hombres y mujeres presentan una diferenciación clara des- de la biología; sin embargo, las variantes comportamentales, sentimentales y de pensamiento se atribuyen más a la influencia de la cultura. Por ello, la presente investigación pretendió conocer el significado contemporáneo del rol de género que hombres y mujeres consideran tener. Se trabajó con una muestra de 300 jóvenes universitarios repartidos equitativamente por sexo. Como instrumento de recolección de datos se utilizó la técnica de redes semánticas naturales. Los resultados muestran diferencias significativas, encontrándose que los hombres se definen con un rol que implica proteger, proveer, comprender, ser profesio- nista, seguro y amoroso, en comparación con las mujeres, que indicaron verse como profesionistas, independientes, esposas o amas de casa, cuyo rol es com- partir y educar. Finalmente, para la definición de lo que a los hombres del país les toca ser y hacer, se observó que los varones se definieron como profesionis- tas, honestos, inteligentes, fuertes, amables, emprendedores, padres y libres, mientras que las mujeres los definieron como padres, proveedores, profesionistas, fieles, honestos y protectores. Esto permite afirmar que los roles que viven los jóvenes universitarios muestran cambios importantes respecto de los roles sexuales tradicionales de la cultura mexicana

    Nitrogen compounds removal from oil-derived middle distillates by MIL-101(Cr) and its impact on ULSD production by hydrotreating

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    Es un articulo sobre sintesis caracterizacion de catalizadoresoil) for ultra-low sulfur diesel (ULSD) production by hydrotreating (HDT) were pretreated by selective nitrogen organic compounds (NOC) adsorption. Highly crystalline metal-organic framework (MOF) MIL-101(Cr) prepared with propylene oxide (proton scavenger) as textural improver was employed to that end. MOF was characterized by N2 physisorption, X-ray diffraction, thermal analysis, infrared, Raman and UV-vis spectroscopies, and electron microscopy (SEM and HR-TEM). NOC removal was performed at room temperature and atmospheric pressure, the adsorbent being easily regenerable under mild conditions. Extruded MOF efficiently removed NOC from real feedstocks to concentrations ~ 80 ppm, allowing ULSD production at much milder conditions to those used during pristine feedstocks HDT. Operating temperature could be greatly diminished (from 350°C to 330°C, at 56 kg/sq cm (5.77 MPa), LHSV = 1.5/h, H2/oil = 2500 cy ft/bbl (445 cu m/cu m)) which could notably prolong cycle life of NiMo/Al2O3 formulation used.SENER-CONACYT-HIDROCARBUROS FUND IMP 00117, 6105

    Dibenzothiophene hydrodesulfurization over P-CoMo on sol-gel alumina modified by La addition. Effect of rare-earth content

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    articuloAlumina-lanthana (La at 1, 3, or 5 wt%) supports were prepared by sol-gel from Al alkoxide sol where La(NO 3 ) 3 was added. Annealed (550 °C) xerogels were characterized by N 2 physisorption, thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy- energy dispersive spectroscopy (SEM-EDS), CO 2 -adsorption studied in IR region, Raman and ultraviolet-vis (UV-vis) spectroscopies. The texture of amorphous binary matrices of high La dispersion was adequate to applications in catalysts for middle distillates hydrodesulfurization (HDS). Generally, the amount and strength of surface basic sites increased with La content in solids. Mo (at 2.8 at. nm −2 ) and Co (at Co/(Co+Mo) = 0.3) were deposited over carriers by one-pot simultaneous impregnation in the presence of PO 4 3− (P 2 O 5 /(NiO+MoO 3 ) = 0.2 mass ratio). Calcined (400 °C) Co-Mo-P impregnated precursors had decreased basicity as to that of corresponding carriers, suggesting strong La-deposited species interaction. As La content in carriers increased Mo=O Raman stretching vibrations shifted to lower wave-numbers (949 to 935 cm −1 ) suggesting octahedral molybdates coordination change to tetrahedral. Although La at the lowest concentration (1 wt%) enhanced dibenzothiophene, HDS (~38% higher as to the Al 2 O 3 -supported formulation) desulfurization was significantly diminished at augmented content. Presence of hardly sulfidable tetrahedral Mo originated during impregnation at basic conditions in pores of La-modified carriers seemed to dictate observed behavior. Rare earth content in formulations enhanced selectivity to biphenyl.: J. Escobar acknowledges financial support from IMP (Y.00105) and SENER-CONACYTHidrocarburos (115086) fund

    Immune protection against Trypanosoma cruzi induced by TcVac4 in a canine model

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    Chagas disease, caused by Trypanosoma cruzi, is endemic in southern parts of the American continent. Herein, we have tested the protective efficacy of a DNA-prime/T. rangeli-boost (TcVac4) vaccine in a dog (Canis familiaris) model. Dogs were immunized with two-doses of DNA vaccine (pcDNA3.1 encoding TcG1, TcG2, and TcG4 antigens plus IL-12- and GMCSF- encoding plasmids) followed by two doses of glutaraldehyde-inactivated T. rangeli epimastigotes (TrIE); and challenged with highly pathogenic T. cruzi (SylvioX10/4) isolate. Dogs given TrIE or empty pcDNA3.1 were used as controls. We monitored post-vaccination and post-challenge infection antibody response by an ELISA, parasitemia by blood analysis and xenodiagnosis, and heart function by electrocardiography. Post-mortem anatomic and pathologic evaluation of the heart was conducted. TcVac4 induced a strong IgG response (IgG2>IgG1) that was significantly expanded post-infection, and moved to a nearly balanced IgG2/IgG1 response in chronic phase. In comparison, dogs given TrIE or empty plasmid DNA only developed high IgG titers with IgG2 predominance in response to T. cruzi infection. Blood parasitemia, tissue parasite foci, parasite transmission to triatomines, electrocardiographic abnormalities were significantly lower in TcVac4-vaccinated dogs than was observed in dogs given TrIE or empty plasmid DNA only. Macroscopic and microscopic alterations, the hallmarks of chronic Chagas disease, were significantly decreased in the myocardium of TcVac4-vaccinated dogs.We conclude that TcVac4 induced immunity was beneficial in providing resistance to T. cruzi infection, evidenced by control of chronic pathology of the heart and preservation of cardiac function in dogs. Additionally, TcVac4 vaccination decreased the transmission of parasites from vaccinated/infected animals to triatomines.CONACYT PROY No. 156701 UAEM PROY No. 2381/2006U National Institutes of Health/National Institute of Allergy and Infectious Diseases http://www.niaid.nih.gov/Pages/ default.aspx GRANT NUMBER (AI072538) NJG; American Heart Association http://www.heart.org/ HEARTORG/ GRANT NUMBER (0855059F) to NJG

    Variability of indication criteria in knee and hip replacement: an observational study

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    <p>Abstract</p> <p>Background</p> <p>Total knee (TKR) and hip (THR) replacement (arthroplasty) are effective surgical procedures that relieve pain, improve patients' quality of life and increase functional capacity. Studies on variations in medical practice usually place the indications for performing these procedures to be highly variable, because surgeons appear to follow different criteria when recommending surgery in patients with different severity levels. We therefore proposed a study to evaluate inter-hospital variability in arthroplasty indication.</p> <p>Methods</p> <p>The pre-surgical condition of 1603 patients included was compared by their personal characteristics, clinical situation and self-perceived health status. Patients were asked to complete two health-related quality of life questionnaires: the generic SF-12 (Short Form) and the specific WOMAC (Western Ontario and Mcmaster Universities) scale. The type of patient undergoing primary arthroplasty was similar in the 15 different hospitals evaluated.</p> <p>The variability in baseline WOMAC score between hospitals in THR and TKR indication was described by range, mean and standard deviation (SD), mean and standard deviation weighted by the number of procedures at each hospital, high/low ratio or extremal quotient (EQ<sub>5-95</sub>), variation coefficient (CV<sub>5-95</sub>) and weighted variation coefficient (WCV<sub>5-95</sub>) for 5-95 percentile range. The variability in subjective and objective signs was evaluated using median, range and WCV<sub>5-95</sub>. The appropriateness of the procedures performed was calculated using a specific threshold proposed by Quintana et al for assessing pain and functional capacity.</p> <p>Results</p> <p>The variability expressed as WCV<sub>5-95 </sub>was very low, between 0.05 and 0.11 for all three dimensions on WOMAC scale for both types of procedure in all participating hospitals. The variability in the physical and mental SF-12 components was very low for both types of procedure (0.08 and 0.07 for hip and 0.03 and 0.07 for knee surgery patients). However, a moderate-high variability was detected in subjective-objective signs. Among all the surgeries performed, approximately a quarter of them could be considered to be inappropriate.</p> <p>Conclusions</p> <p>A greater inter-hospital variability was observed for objective than for subjective signs for both procedures, suggesting that the differences in clinical criteria followed by surgeons when indicating arthroplasty are the main responsible factors for the variation in surgery rates.</p

    Oral versus intramuscular administration of vitamin B12 for vitamin B12 deficiency in primary care : a pragmatic, randomised, non-inferiority clinical trial (OB12)

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    The trial was financed by Ministerio de Sanidad y Consumo Español through their call for independent clinical research, Orden Ministerial SAS/2377, 2010 (EC10-115, EC10-116, EC10-117, EC10-119, EC10-122); CAIBER—Spanish Clinical Research Network, Instituto de Salud Carlos III (ISCIII) (CAI08/010044); and Gerencia Asistencial de Atención Primaria de Madrid. This study is also supported by the Spanish Clinical Research Network (SCReN), funded by ISCIII-Subdirección General de Evaluación y Fomento de la Investigación, project number PT13/0002/0007, within the National Research Program I+D+I 2013-2016 and co-funded with European Union ERDF funds (European Regional Development Fund). This project received a grant for the translation and publication of this article from the Foundation for Biomedical Research and Innovation in Primary Care (FIIBAP) Call 2017 for grants to promote research programs.Objectives To compare the effectiveness of oral versus intramuscular (IM) vitamin B12 (VB12) in patients aged ≥65 years with VB12 deficiency. Design Pragmatic, randomised, non-inferiority, multicentre trial in 22 primary healthcare centres in Madrid (Spain). Participants 283 patients ≥65 years with VB12 deficiency were randomly assigned to oral (n=140) or IM (n=143) treatment arm. Interventions The IM arm received 1 mg VB12 on alternate days in weeks 1–2, 1 mg/week in weeks 3–8 and 1 mg/month in weeks 9–52. The oral arm received 1 mg/day in weeks 1–8 and 1 mg/week in weeks 9–52. Main outcomes Serum VB12 concentration normalisation (≥211 pg/mL) at 8, 26 and 52 weeks. Non-inferiority would be declared if the difference between arms is 10% or less. Secondary outcomes included symptoms, adverse events, adherence to treatment, quality of life, patient preferences and satisfaction. Results The follow-up period (52 weeks) was completed by 229 patients (80.9%). At week 8, the percentage of patients in each arm who achieved normal B12 levels was well above 90%; the differences in this percentage between the oral and IM arm were −0.7% (133 out of 135 vs 129 out of 130; 95% CI: −3.2 to 1.8; p>0.999) by per-protocol (PPT) analysis and 4.8% (133 out of 140 vs 129 out of 143; 95% CI: −1.3 to 10.9; p=0.124) by intention-to-treat (ITT) analysis. At week 52, the percentage of patients who achieved normal B12 levels was 73.6% in the oral arm and 80.4% in the IM arm; these differences were −6.3% (103 out of 112 vs 115 out of 117; 95% CI: −11.9 to −0.1; p=0.025) and −6.8% (103 out of 140 vs 115 out of 143; 95% CI: −16.6 to 2.9; p=0.171), respectively. Factors affecting the success rate at week 52 were age, OR=0.95 (95% CI: 0.91 to 0.99) and having reached VB12 levels ≥281 pg/mL at week 8, OR=8.1 (95% CI: 2.4 to 27.3). Under a Bayesian framework, non-inferiority probabilities (Δ>−10%) at week 52 were 0.036 (PPT) and 0.060 (ITT). Quality of life and adverse effects were comparable across groups. 83.4% of patients preferred the oral route. Conclusions Oral administration was no less effective than IM administration at 8 weeks. Although differences were found between administration routes at week 52, the probability that the differences were below the non-inferiority threshold was very low.Publisher PDFPeer reviewe

    Obstetric outcomes of sars-cov-2 infection in asymptomatic pregnant women

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    Altres ajuts: Fondo Europeo de Desarrollo Regional (FEDER)Around two percent of asymptomatic women in labor test positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Spain. Families and care providers face childbirth with uncertainty. We determined if SARS-CoV-2 infection at delivery among asymptomatic mothers had different obstetric outcomes compared to negative patients. This was a multicenter prospective study based on universal antenatal screening for SARS-CoV-2 infection. A total of 42 hospitals tested women admitted for delivery using polymerase chain reaction, from March to May 2020. We included positive mothers and a sample of negative mothers asymptomatic throughout the antenatal period, with 6-week postpartum follow-up. Association between SARS-CoV-2 and obstetric outcomes was evaluated by multivariate logistic regression analyses. In total, 174 asymptomatic SARS-CoV-2 positive pregnancies were compared with 430 asymptomatic negative pregnancies. No differences were observed between both groups in key maternal and neonatal outcomes at delivery and follow-up, with the exception of prelabor rupture of membranes at term (adjusted odds ratio 1.88, 95% confidence interval 1.13-3.11; p = 0.015). Asymptomatic SARS-CoV-2 positive mothers have higher odds of prelabor rupture of membranes at term, without an increase in perinatal complications, compared to negative mothers. Pregnant women testing positive for SARS-CoV-2 at admission for delivery should be reassured by their healthcare workers in the absence of symptoms

    The origin and speciation of orchids

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    SummaryOrchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of an up-to-date phylogeographic analysis.We present a new Orchidaceae phylogeny based on combined high-throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants.The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica.These results alter our understanding of the geographic origin of orchids, previously proposed as Australian, and pinpoint Central America as a region of recent, explosive speciation

    Jardins per a la salut

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    Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia. Assignatura: Botànica farmacèutica. Curs: 2014-2015. Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són el recull de les fitxes botàniques de 128 espècies presents en el Jardí Ferran Soldevila de l’Edifici Històric de la UB. Els treballs han estat realitzats manera individual per part dels estudiants dels grups M-3 i T-1 de l’assignatura Botànica Farmacèutica durant els mesos de febrer a maig del curs 2014-15 com a resultat final del Projecte d’Innovació Docent «Jardins per a la salut: aprenentatge servei a Botànica farmacèutica» (codi 2014PID-UB/054). Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pels professors de l’assignatura. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica. També s’ha pretès motivar els estudiants a través del retorn de part del seu esforç a la societat a través d’una experiència d’Aprenentatge-Servei, deixant disponible finalment el treball dels estudiants per a poder ser consultable a través d’una Web pública amb la possibilitat de poder-ho fer in-situ en el propi jardí mitjançant codis QR amb un smartphone
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