1,031 research outputs found
Preyssler Heteropolyacids in the Self-Etherification of 5-Hydroxymethylfurfural to 5,5′-[Oxybis(methylene)]bis-2-furfural Under Mild Reaction Conditions
The synthesis of 5,5′-[oxybis(methylene)]bis-2-furfural (OBMF) from 5-hydroxymethylfurfural (5-HMF) was studied using bulk and alumina-supported Preyssler heteropolyacids (HPAs). The formation of OBMF was related to the amount of Brønsted acid sites, and the lowest yield of OBMF was obtained with supported HPAs. However, the Lewis acidity of the HPA supported on Al2O3 favored the formation of 2,5-dimethylfurane. The effects of solvent, catalyst loading, temperature, and reaction time on the selectivity to OBMF from 5-HMF were studied to optimize OBMF production using bulk Preyssler HPAs; a yield of 84 % to OBMF was obtained at 5 h and 343 K. These results demonstrate that bulk Preyssler HPA is a good candidate for OBMF synthesis under mild reaction conditions.Fil: Páez, Alexander. Universidad Pedagógica y Tecnológica de Colombia; ColombiaFil: Rojas, Hugo A.. Universidad Pedagógica y Tecnológica de Colombia;Fil: Portilla Zúñiga, Omar Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Sathicq, Angel Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Afonso, Carlos A. M.. Universidade de Lisboa; PortugalFil: Romanelli, Gustavo Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Ciencias Aplicadas ; ArgentinaFil: Martínez, José J.. Universidad Pedagógica y Tecnológica de Colombia; Colombi
"Fire burns matter: A case-control study of severe accidental burns in pediatric patients"
"Objective: We aimed to identify factors associated with severe accidental burns in patients ≤12 years old.
Materials and methods: We conducted a matched case-control study, in which we retrospectively reviewed the
medical records of children treated in a single institution from 2014-2016. We classified the cases (patients with
severe burns) and controls (patients with non-severe burns) according to the criteria of the American Burn
Association. We used multivariate conditional logistic regression analysis to identify the relationship between the
etiology of burns and their severity.
Results: We reviewed 180 cases and 90 controls. The most common etiology of burns was boiling water in both
cases (65.6%) and controls (83.3%). Most burns occurred inside the home (84.1%) and in the afternoon (37.4%).
Multivariate analysis identified that severe burns were mainly due to exposure to fire (odds ratio [OR]: 3.22, 95%
confidence interval [CI]: 1.53-6.81). Similarly, these patients were more likely to live in a rural area (OR: 2.96, 95%
CI: 1.17-6.19).
Conclusions: In pediatric patients ≤12 years of age severe accidental burns are more likely to be caused by fire
compared to boiling water. Public health interventions should focus on populations located in rural areas.
Application of web design in the influence of positioning, based on SEO methodology, applied to the company the company EuroPerú S.A.C.
The project consists of the implementation of the SEO methodology to the website of the
company Europeru S.A.C under the brand name "modaGuiss" with the aim of generating a
presence on the internet and positioning it in the first Google search results; to increase the
passive and active traffic of the page and therefore, increase in potential customers, interactions,
followers, etc. Finally, the web application “ModaGuiss | Footwear and Shoes” starting from the
design of the page through the analysis of the competition with free tools for searching and
filtering meta information for subsequent implementation of indexing in the consoles of the
aforementioned search engines. With what was obtained as a result, appear in the search results
with the words: ModaGuiss, Zapatos Guiss, Zapatos Huancayo, etc. However, to climb positions
it was necessary to generate backlinks to our page and maintain constant activity. At the end of
the development of the web app and the positioning, good results were obtained such as the
positioning of the brand and domain name, by comparing the page without SEO and the page
created with SEO, it was possible to specify that the SEO methodology allows you to position
quickly in search engines, unlike not using it, which takes months or years to position your page.Campus At
Tasas netas de acreción de carbonato de calcio en el complejo de ecosistemas marinos-costeros de la Ensenada Rancho Luna, Cienfuegos, Cuba
Debido a las emisiones cada vez mayores de dióxido de carbono a la atmósfera, la absorción de este gas por el océano se realiza a gran velocidad, provocando un aumento en la acidez del agua de mar. Este proceso, conocido como acidificación oceánica, conlleva a que en muchos organismos calcificadores se reduzca la capacidad de formar sus estructuras de carbonato de calcio. El objetivo de esta investigación fue determinar las tasas netas de acreción de carbonato de calcio (g CaCO3 cm-2 año-1) de taxones de sucesión temprana, en el complejo de ecosistemas marinos-costeros de la Ensenada Rancho Luna,
Cienfuegos. Para la cuantificación de la tasas netas de acreción de carbonato de calcio se construyeron 12 dispositivos de muestreo basados en la metodología Vargas-Ángel et al. en el 2015, posicionándose seis de ellos en cada ecosistema estudiado (manglar y arrecife). Los valores medios de netas de acreción de carbonato de calcio fueron de 0.87 ± 0.19 g CaCO3 cm-2 año-1 en el arrecife y 0.59 ± 0.05 g CaCO3 cm-2 año-1 en el manglar. Se identificaron siete taxones, correspondientes a cuatro grupos funcionales de sucesión temprana, el césped (turf), el CaCO3 /sedimento, el grupo funcional Sin Calcio y las algas coralinas costrosas. Estas últimas fueron las principales aportadoras de CaCO3, encontrándose principalmente en el arrecife. Se determinó a la magnesita como forma cristalina de CaCO3 dominante, y las algas coralinas costrosas, el grupo de mayor vulnerabilidad ante el efecto de la acidificación oceánica.
Recibido: 23.09.2022 Aceptado: 06.09.2023
Editor: Susana Perera Valderram
A semente não é suficiente, a árvore deve ser acompanhada: importância do contexto de implementação em programas de educação ambiental
There is a growing consensus on the advantages and benefits of implementing environmental education programs in school communities, but few studies focus on the conditions that make it possible for them to be incorporated as daily practices. The purpose of this research paper was to identify contextual barriers and facilitators of the implementation of a program of pedagogical innovation and education for the sustainability of the municipality, carried out in a city in the south of Chile. The sample consisted of 36 teacher coordinators of schools where the program is implemented. During an assessment session, the researchers applied an open-ended question survey, aimed at investigating the contextual factors affecting the implementation. Subsequently, through focal groups, these factors were delved into with the same participants. The authors found that the critical factors are: (1) the support and motivation of the community; (2) the curricular integration of the program; (3) the implementation supports; and (4) the expertise of the executing teacher. The transculturality of the identified factors is analyzed and the practical and theoretical implications of the findings are discussed.Existe un consenso cada vez mayor sobre las ventajas y los beneficios de implementar programas de educación ambiental en las comunidades escolares, pero hay pocos estudios acerca de las condiciones que hacen posible que sean incorporados como prácticas cotidianas. El propósito de este artículo de investigación fue identificar barreras y facilitadores contextuales de la implementación de un programa de innovación pedagógica y educación para la sustentabilidad de la municipalidad llevado a cabo en una ciudad del sur de Chile. Participaron 36 docentes coordinadores de escuelas donde se implementa el programa. A través de una jornada de evaluación se aplicó una encuesta de preguntas abiertas orientada a indagar los factores contextuales que afectan la implementación. Después, mediante grupos focales, se profundizó en estos factores con los mismos participantes. Se encontró que los factores críticos son: 1) el apoyo y motivación de la comunidad, 2) la integración curricular del programa, 3) los soportes de implementación, y 4) la experticia del docente ejecutor. Se analiza la transculturalidad de los factores identificados y se discuten las implicancias prácticas y teóricas de los hallazgos.Existe um consenso crescente sobre as vantagens e benefícios da implementação de programas de educação ambiental nas comunidades escolares, mas há poucos estudos sobre as condições que permitem que eles sejam incorporados como práticas cotidianas. O objetivo deste artigo de pesquisa foi identificar barreiras e facilitadores contextuais da implementação de um programa de inovação e educação pedagógica para a sustentabilidade do município, realizado em uma cidade no sul do Chile. Participaram 36 professores coordenadores das escolas onde o programa é implementado. Durante um dia de avaliação, um questionário de perguntas abertas foi aplicado para investigar os fatores contextuais que afetam a implementação. Então, por meio de grupos focais, esses fatores foram aprofundados com os mesmos participantes. Constatou-se que os fatores críticos são: 1) apoio e motivação da comunidade, 2) integração curricular do programa, 3) apoio à implementação e 4) a experiência do professor em execução. A transculturalidade dos fatores identificados é analisada e as implicações práticas e teóricas dos resultados são discutidas
Role of echocardiography in the ventricular assessment of the transplanted heart versus heart rejection
BACKGROUND: Heart transplantation is an alternative for individuals with end-stage heart disease. However, episodes of heart rejection (HR) are frequent and increase morbidity and mortality, requiring the use of an accurate non-invasive exam for their diagnosis, since endomyocardial biopsy (EMB) is not a complication-free procedure. OBJECTIVE: To compare the parameters obtained by use of Doppler echocardiography in a group of transplanted patients with HR (TX1) and another group of transplanted patients without rejection (TX0), having as reference a control group (CG) and observing the behavior of the left ventricular systo-diastolic function expressed as the myocardial performance index (MPI) METHODS: Transthoracic echocardiographies were performed from January 2006 to January 2008 to prospectively assess 47 patients divided into three groups: CG (36.2%); TX0 (38.3%); and TX1 (25.5%). The MPI was compared between the groups, and data were analyzed by use of Fisher exact test and nonparametric Kruskal-Wallis test, both with significance level of 5%. RESULTS: The groups did not differ regarding age, weight, height, and body surface. When compared to GC, TX0 and TX1 showed a change in the left ventricular systo-diastolic function, expressed as an increase in MPI, which was greater in TX1 [0.38 (0.29 - 0.44); 0.47 (0.43 - 0.56); 0.58 (0.52 - 0.74), respectively; p < 0.001]. CONCLUSION: Echocardiography was a very accurate test to detect changes in the systo-diastolic function of the transplanted heart; however, it did not prove to be reliable to replace BEM in the safe diagnosis of HR.FUNDAMENTO: O Transplante Cardíaco (TC) é uma alternativa para os indivíduos com doença cardíaca terminal. Na evolução pós-transplante, a ocorrência de episódios de Rejeição Cardíaca (RC) é evento frequente que aumenta a morbimortalidade, sendo necessário o emprego de exame não invasivo com boa acurácia para seu diagnóstico, pois a Biópsia Endomiocárdica (BEM) não é um procedimento isento de complicações. OBJETIVO: Comparar parâmetros obtidos com o princípio Doppler, entre os pacientes transplantados com RC (TX1) e os pacientes transplantados sem rejeição (TX0); utilizando como referência o Grupo Controle (GC) e observando o comportamento da função sistodiastólica ventricular esquerda expressa por meio do Índice de Performance Miocárdica (IPM). MÉTODOS: Foram realizados ecocardiogramas transtorácicos no período de janeiro de 2006 a janeiro de 2008, para a avaliação prospectiva de 47 pacientes, subdivididos em GC (36,2%), TX0 (38,3%) e TX1 (25,5%), comparando-se o IPM entre eles. Para a análise dos dados foram realizados os testes exato de Fisher e o não paramétrico de Kruskal-Wallis, ambos com nível de significância de 5%. RESULTADOS: Os grupos não diferiram em relação a idade, peso, altura e superfície corpórea. Quando comparado ao GC, TX0 e TX1 apresentaram alteração da função sistodiastólica ventricular esquerda, expressa como aumento do IPM, que foi mais intenso no TX1 [0,38 (0,29 - 0,44) X 0,47 (0,43 - 0,56) X 0,58 (0,52 - 0,74) p < 0,001]. CONCLUSÃO: O ecocardiograma mostrou-se como exame de boa acurácia na detecção das alterações da função sistodiastólica do coração transplantado; entretanto, não foi confiável como método substituto da BEM para o diagnóstico seguro de RC.1031103
Ciguatoxin occurrence in food-web components of a Cuban Coral Reef Ecosystem: Risk-assessment implications
In Cuba, ciguatera poisoning associated with fish consumption is the most commonly occurring non-bacterial seafood-borne illness. Risk management through fish market regulation has existed in Cuba for decades and consists of bans on selected species above a certain weight; however, the actual occurrence of ciguatoxins (CTXs) in seafood has never been verified. From this food safety risk management perspective, a study site locally known to be at risk for ciguatera was selected. Analysis of the epiphytic dinoflagellate community identified the microalga Gambierdiscus. Gambierdiscus species included six of the seven species known to be present in Cuba (G. caribaeus, G. belizeanus, G. carpenteri, G. carolinianus, G. silvae, and F. ruetzleri). CTX-like activity in invertebrates, herbivorous and carnivorous fishes were analyzed with a radioligand receptor-binding assay and, for selected samples, with the N2A cell cytotoxicity assay. CTX activity was found in 80% of the organisms sampled, with toxin values ranging from 2 to 8 ng CTX3C equivalents g−1 tissue. Data analysis further confirmed CTXs trophic magnification. This study constitutes the first finding of CTX-like activity in marine organisms in Cuba and in herbivorous fish in the Caribbean. Elucidating the structure–activity relationship and toxicology of CTX from the Caribbean is needed before conclusions may be drawn about risk exposure in Cuba and the wider Caribbean.info:eu-repo/semantics/publishedVersio
Reducing Nitrogen Dosage in Triticum durum Plants with Urea-Doped Nanofertilizers
Nanotechnology is emerging as a very promising tool towards more efficient and sustainable
practices in agriculture. In this work, we propose the use of non-toxic calcium phosphate nanoparticles
doped with urea (U-ACP) for the fertilization of Triticum durum plants. U-ACP nanoparticles present
very similar morphology, structure, and composition than the amorphous precursor of bone mineral,
but contain a considerable amount of nitrogen as adsorbed urea (up to ca. 6 wt % urea). Tests on
Triticum durum plants indicated that yields and quality of the crops treated with the nanoparticles at
reduced nitrogen dosages (by 40%) were unaltered in comparison to positive control plants, which
were given the minimum N dosages to obtain the highest values of yield and quality in fields. In
addition, optical microscopy inspections showed that Alizarin Red S stained nanoparticles were
able to penetrate through the epidermis of the roots or the stomata of the leaves. We observed that
the uptake through the roots occurs much faster than through the leaves (1 h vs. 2 days, respectively).
Our results highlight the potential of engineering nanoparticles to provide a considerable efficiency
of nitrogen uptake by durum wheat and open the door to design more sustainable practices for
the fertilization of wheat in fields.This research was funded by Fondazione CARIPLO (project no. 2016-0648: Romancing the stone:
size-controlled HYdroxyaPATItes for sustainable Agriculture–HYPATIA) and the Spanish Ministerio de Ciencia,
Innovación y Universidades (MCIU/AEI/FEDER) with the Projects NanoSmart (RYC-2016-21042) and NanoVIT
(RTI-2018-095794-A-C22). GBRR also acknowledges the Spanish MICINN for her postdoctoral contract within
the Juan de la Cierva Program (JdC-2017)
Preyssler Heteropolyacids in the Self-Etherification of 5-Hydroxymethylfurfural to 5,5′-[Oxybis(methylene)]bis-2-furfural Under Mild Reaction Conditions
The synthesis of 5,5′-[oxybis(methylene)]bis-2-furfural (OBMF) from 5-hydroxymethylfurfural (5-HMF) was studied using bulk and alumina-supported Preyssler heteropolyacids (HPAs). The formation of OBMF was related to the amount of Brønsted acid sites, and the lowest yield of OBMF was obtained with supported HPAs. However, the Lewis acidity of the HPA supported on Al2O3 favored the formation of 2,5-dimethylfurane. The effects of solvent, catalyst loading, temperature, and reaction time on the selectivity to OBMF from 5-HMF were studied to optimize OBMF production using bulk Preyssler HPAs; a yield of 84 % to OBMF was obtained at 5 h and 343 K. These results demonstrate that bulk Preyssler HPA is a good candidate for OBMF synthesis under mild reaction conditions.Centro de Investigación y Desarrollo en Ciencias Aplicada
Retos del derecho constitucional contemporáneo
1 documento en PDF de 16 páginas.Con reflexiones académicas sobre el “neoconstitucionalismo”, este libro recoge conclusiones de la experiencia constitucional en Colombiay en otros países. Especialmente crítico, destaca los aciertos del neoconstitucionalismo y plantea cómo este ha sido incapaz de fortalecer la justicia y de modelar una sociedad más incluyente, por lo cual los autores recomiendan una revisión profunda de sus tesis principales y retomar las fuentes propias de la juridicidad humana y la universalidad de sus bienes básicos y fundamentales.PRESENTACIÓN
CAPÍTULO PRIMERO LA CORTE CONSTITUCIONAL ANTE EL TRIBUNAL DE LA HISTORIA
1. Introducción
2. El "núcleo puro y duro de la Constitución de 1991"
3. "Yo doy las órdenes". La ingeniería social de la Corte Constitucional de Colombia
4. Constitución y Corte Constitucional: una misma cosa
5. Nuevamente el "deseo" como fundamento de la juridicidad: un juez que dice mentiras
6. A modo de conclusión: los poderosos también caen
CAPÍTULO II LOS DERECHOS HUMANOS. ¿ENTRE DESEOS PARTICULARES Y BIENES FUNDAMENTALES?
7. La sociedad secularizada
8. Las "lisonjas de los bribones"
9. De Protágoras a Rorty
10. Rawls, Nozick, Hume, Constant
11. Pluralismo sin fundamentalismos
12. El riesgo del "mandarinismo"
13. El juez constitucional. ¿Imparcial e independiente?
14. El riesgo de la manipulación ideológica del derecho
15. Algunos rasgos del nuevo constitucionalismo
16. ¿Oligarquías del fundamentalismo secularista?
17. ¿Magistratura al servicio de la justicia o al servicio de intereses?
18. Opinión pública y limitación del poder
19. Epílogo. El ojo independiente de la sociedad y los pequeños pelotones
CAPÍTULO III POSITIVISMO, NEOCONSTITUCIONALISMO Y ACTIVISMO JUDICIAL
20. Preliminares
A) EL POSITIVISMO JURÍDICO DE HANS KELSEN
21. Autointerés y conflicto
22. La norma
23. Activismo judicial
24. Conclusión. Dominación ilegal y tiranía
B) NEOCONSTITUCIONALISMO
25. El sujeto de derechos y la despolitización de la convivencia
26. Los derechos
27. Activismo judicial
28. Estado de naturaleza y anarquismo
29. Consideraciones finales
CAPÍTULO IV LAS APORÍAS PRESENTES DEL DERECHO CONSTITUCIONAL
30. Constitución, derecho constitucional y constitucionalismo
31. Constitucionalismo, derecho público y derecho privado
32. Constitución del Estado y constructivismo social
33. ¿Separación de poderes?
34. Un escolio sobre el "judicialismo"
35. El funcionalismo federalista
36. Constitucionalismo y personalismo
37. Neo y posconstitucionalismo
CAPÍTULO V DEL LAICISMO A LA LAICIDAD. UNAS REFLEXIONES (NO EXCLUSIVAMENTE) ESPAÑOLAS
38. ¿De nominibus non est disputandum?" o "res denominatur a potiori?"
39. Al principio, "non est potestas nisi a Deo"
40. El Estado moderno y sus transformaciones. La puesta en plural del pecado original y la doctrina social de la Iglesia como contestación cristiana del mundo moderno
41. La ruina espiritual de un pueblo por efecto de una política
42. Las incoherencias de la predicación actual y la reedificación del derecho público cristiano
CAPÍTULO VI LAS RELACIONES ENTRE RELIGIÓN Y POLÍTICA EN LA SOCIEDAD POSTSECULAR DEL SIGLO XXI
43. Presentación
44. La política
45. La religión
46. Las relaciones entre política y religión
47. La actual trascendencia social, cultural y política del fenómeno religioso
48. El debate Habermas - Ratzinger y el advenimiento de la llamada sociedad postsecular
CAPÍTULO VII EL CONSTITUCIONALISMO FRENTE A LAS CONSTITUCIONES CONTEMPORÁNEAS
49. Introducción
50. El concepto de Constitución
51. La clasificación de las constituciones y una mirada realista
52. La necesidad de "desestatizar" las fuentes del derecho constitucional
53. Una evaluación del principio de separación de poderes
54. La diferencia entre el mundo del "rule of law" y del Estado de derecho
55. El nacimiento del control de constitucionalidad
56. La tradición constitucional en el reconocimiento de los derechos y libertades
57. Las garantías y su progresiva fragmentación en los textos constitucionales
58. El dimensionamiento de una Constitución
59. Las llamadas constituciones modernas
60. Las nuevas tendencias constitucionales
61. Conclusión. El ejemplo constitucional anglosajón
CAPÍTULO VIII LA TEORÍA DE LOS PRINCIPIOS Y EL ESTADO CONSTITUCIONAL. LUCES Y SOMBRAS
62. El Estado constitucional y los principios jurídico-constitucionales
63. La teoría de los principios en la teoría contemporánea del derecho
64. Principios jurídicos y valores constitucionales
65. Criterios distintivos entre principios y reglas
66. La cuestión del fundamento de los principios. Una asignatura pendiente en la teoría principalista de los derechos
CAPÍTULO IX EL CONTROL DE CONSTITUCIONALIDAD DE REFORMAS CONSTITUCIONALES. ALGUNAS SALIDAS PARA LA ENCRUCIJADA CONTRAMAYORITARIA
67. Introducción
68. Las sombras del control de reformas por sustitución
69. Algunas salidas
70. La aplicabilidad de estas alternativas al caso colombiano
BIBLIOGRAFÍ
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