767 research outputs found
Evaluación de metodologías para la aplicación de sistemas de protección contra la corrosión en el interior de tanques de lastre en embarcaciones marinas
In this paper, different methodologies of surface preparation for applyinga paint system used in ballast tanks of marine vessels are studied andtheir influences in the performance of the paint system are evaluated.Typical rusts found on boat surfaces were characterized, field tests wereconducted with different surface preparations in hard-to-reach areas,controlling the contamination degree by soluble salts and comparingdifferent methods (Bresle method, Sleeve test, Saltsmart test and ionchromatography) and different roughness profiles (sand blasting, powergrinding and sandpaper, scraping and picketing) in order to determinethe more efficient combination of methods for the surface preparation inhard-to-reach areas. Different properties of a paint system were evaluateduring laboratory and field exposure tests. The final exposure time was 7months. It was found that the methods of surface preparation by picketingand power grinding + sandpaper have the higher salt contents (> 10 μg/cm2), exceeding the maximum permitted limit of 5.0 μg/cm2Este artículo presenta los resultados de la evaluación del desempeño ymetodologías de preparación superficial para la aplicación de un sistemade pinturas utilizado en tanques de lastre de embarcaciones marinas.Se caracterizaron las herrumbres típicas encontradas en superficies deembarcaciones, se realizaron pruebas de campo haciendo diferentespreparaciones de superficies en áreas de difícil acceso que permitierancontrolar el grado de contaminación por sales solubles, comparandodiferentes métodos (Método Bresle, Sleeve test, Saltsmart, cromatografíaiónica) y varios perfiles de anclaje (sand blasting, grata y lija, escariadory piqueteo) con el fin de determinar la combinación de los métodos máseficientes en la práctica para la preparación de zonas de difícil acceso. Seevaluaron las propiedades de un sistema de pinturas en laboratorio y encampo durante 7 meses de exposición. Se encontró que los métodos depreparación de superficie por piqueteo y grata + lija son los que presentanel mayor contenido de sales (> de 10 μg/cm2), superando el límitemáximo permitido de 5.0 μg/cm2. A partir del método de preparacióncon escariador están por debajo de los 10 μg/cm2
Evaluation of methodologies for the application of protection systems against corrosion inside ballast tanks in marine vessels
RESUMEN: Este artículo presenta los resultados de la evaluación del desempeño y metodologías de preparación superficial para la aplicación de un sistema de pinturas utilizado en tanques de lastre de embarcaciones marinas. Se caracterizaron las herrumbres típicas encontradas en superficies de embarcaciones, se realizaron pruebas de campo haciendo diferentes preparaciones de superficies en áreas de difícil acceso que permitieran controlar el grado de contaminación por sales solubles, comparando diferentes métodos (Método Bresle, Sleeve test, Saltsmart, cromatografía iónica) y varios perfiles de anclaje (sand blasting, grata y lija, escariador y piqueteo) con el fin de determinar la combinación de los métodos más eficientes en la práctica para la preparación de zonas de difícil acceso. Se evaluaron las propiedades de un sistema de pinturas en laboratorio y en campo durante 7 meses de exposición. Se encontró que los métodos de preparación de superficie por piqueteo y grata + lija son los que presentan el mayor contenido de sales (> de 10 μg/cm2), superando el límite máximo permitido de 5.0 μg/cm2. A partir del método de preparación con escariador están por debajo de los 10 μg/cm2.ABSTRACT: In this paper, different methodologies of surface preparation for applying a paint system used in ballast tanks of marine vessels are studied and their influences in the performance of the paint system are evaluated. Typical rusts found on boat surfaces were characterized, field tests were conducted with different surface preparations in hard-to-reach areas, controlling the contamination degree by soluble salts and comparing different methods (Bresle method, Sleeve test, Saltsmart test and ion chromatography) and different roughness profiles (sand blasting, power grinding and sandpaper, scraping and picketing) in order to determine the more efficient combination of methods for the surface preparation in hard-to-reach areas. Different properties of a paint system were evaluate during laboratory and field exposure tests. The final exposure time was 7 months. It was found that the methods of surface preparation by picketing and power grinding + sandpaper have the higher salt contents (> 10 μg/ cm2), exceeding the maximum permitted limit of 5.0 μg/cm2
A Ribosomal Misincorporation of Lys for Arg in Human Triosephosphate Isomerase Expressed in Escherichia coli Gives Rise to Two Protein Populations
We previously observed that human homodimeric triosephosphate isomerase (HsTIM) expressed in Escherichia coli and purified to apparent homogeneity exhibits two significantly different thermal transitions. A detailed exploration of the phenomenon showed that the preparations contain two proteins; one has the expected theoretical mass, while the mass of the other is 28 Da lower. The two proteins were separated by size exclusion chromatography in 3 M urea. Both proteins correspond to HsTIM as shown by Tandem Mass Spectrometry (LC/ESI-MS/MS). The two proteins were present in nearly equimolar amounts under certain growth conditions. They were catalytically active, but differed in molecular mass, thermostability, susceptibility to urea and proteinase K. An analysis of the nucleotides in the human TIM gene revealed the presence of six codons that are not commonly used in E. coli. We examined if they were related to the formation of the two proteins. We found that expression of the enzyme in a strain that contains extra copies of genes that encode for tRNAs that frequently limit translation of heterologous proteins (Arg, Ile, Leu), as well as silent mutations of two consecutive rare Arg codons (positions 98 and 99), led to the exclusive production of the more stable protein. Further analysis by LC/ESI-MS/MS showed that the 28 Da mass difference is due to the substitution of a Lys for an Arg residue at position 99. Overall, our work shows that two proteins with different biochemical and biophysical properties that coexist in the same cell environment are translated from the same nucleotide sequence frame
Marco activo de recursos de innovación docente: Madrid
Una guía de espacios e instituciones para actividades educativas complementarias en enseñanza secundaria y Formación Profesional
Compromising between European and US allergen immunotherapy schools: Discussions from GUIMIT, the Mexican immunotherapy guidelines
Background: Allergen immunotherapy (AIT) has a longstanding history and still remains the only disease-changing treatment for allergic rhinitis and asthma. Over the years 2 different schools have developed their strategies: the United States (US) and the European. Allergen extracts available in these regions are adapted to local practice. In other parts of the world, extracts from both regions
and local ones are commercialized, as in Mexico. Here, local experts developed a national AIT guideline (GUIMIT 2019) searching for compromises between both schools.
Methods: Using ADAPTE methodology for transculturizing guidelines and AGREE-II for evaluating guideline quality, GUIMIT selected 3 high-quality Main Reference Guidelines (MRGs): the European Academy of Allergy, Asthma and Immunology (EAACI) guideines, the S2k guideline of
various German-speaking medical societies (2014), and the US Practice Parameters on Allergen Immunotherapy 2011. We formulated clinical questions and based responses on the fused evidence available in the MRGs, combined with local possibilities, patient's preference, and costs. We
came across several issues on which the MRGs disagreed. These are presented here along with arguments of GUIMIT members to resolve them. GUIMIT (for a complete English version, see Supplementary data) concluded the following:
Results: Related to the diagnosis of IgE-mediated respiratory allergy, apart from skin prick testing
complementary tests (challenges, in vitro testing and molecular such as species-specific allergens) might be useful in selected cases to inform AIT composition. AIT is indicated in allergic rhinitis and suggested in allergic asthma (once controlled) and IgE-mediated atopic dermatitis. Concerning the correct subcutaneous AIT dose for compounding vials according to the US school: dosing tables and formula are given; up to 4 non-related allergens can be mixed, refraining from mixing high with low protease extracts. When using European extracts: the manufacturer's indications
should be followed; in multi-allergic patients 2 simultaneous injections can be given (100% consensus); mixing is discouraged. In Mexico only allergoid tablets are available; based on doses used in all sublingual immunotherapy (SLIT) publications referenced in MRGs, GUIMIT suggests a probable effective dose related to subcutaneous immunotherapy (SCIT) might be: 50–200% of the monthly SCIT dose given daily, maximum mixing 4 allergens. Also, a table with practical suggestions on non-evidence-existing issues, developed with a simplified Delphi method, is added.
Finally, dissemination and implementation of guidelines is briefly discussed, explaining how we used online tools for this in Mexico.
Conclusions: Countries where European and American AIT extracts are available should adjust AIT according to which school is followed
FANSY POSTCOV: A composite clinical immunological predictive index for post-COVID-19 syndrome unveils distinctive features in a cohort study of mild to critical patients.
Experiencias en el aula: cuarto encuentro de prácticas pedagógicas innovadoras.
Cuarto encuentro de prácticas pedagógicas innovadoras, evento que se llevo a cabo los días 7 y 8 de Octubre de 2019
Experiencias en el aula: cuarto encuentro de prácticas pedagógicas innovadoras.
Cuarto encuentro de prácticas pedagógicas innovadoras, evento que se llevo a cabo los días 7 y 8 de Octubre de 2019
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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