Search

Your search keyword '"Hugo, Martin"' showing total 249 results
Start Over Author "Hugo, Martin"

Refine your results

more »

more »

more »

more »
249 results on '"Hugo, Martin"'

226. Modification of Multi-Wall carbon nanotubes using controlled microwave Irradiation: Experimental determination of the enthalpy change.

Author

Llarena-Bravo, Topacio, Sobral, Hugo Martin, Ordóñez-Romero, César Leonardo, and Alvarez-Zauco, Edgar

Subjects
*CARBON nanotubes, *MAGNETRONS, *TRANSMISSION line theory, *FOURIER transform infrared spectroscopy, *HEAT of formation, *NANOTUBES, *ENTHALPY
Abstract

[Display omitted] • Carbon nanotubes purification assisted by microwaves. • Experimental determination of Enthalpy change energy for carbon nanotubes. • Transmission line theory applied to nanostructures modification. Irradiation of multi-wall carbon nanotubes (MWCNT) was performed at different energy densities to characterize structural changes induced by a highly localized 2.45 GHz electric field. For this purpose, a transversal electric (TE 102) resonant microwave cavity was designed and coupled to a standard 800 W microwave oven magnetron. The nanotubes were sealed inside a Pyrex reactor at 10-4 Torr to avoid oxidation or reactions with the environment. Irradiated MWCNT properties were characterized using Raman Spectroscopy, Fourier Transform Infrared Spectroscopy, Thermogravimetry, Solubility tests and Transmission Electron Microscopy. In this work, the energy densities required to modify the MWCNT structure were obtained through an optical method. From an energy density of 82 J/cm3, nanotubes presented nondestructive structural changes, loss of catalytic particles and a decrease of amorphous carbon structures on the surface. A more effective modification with high purity and clearly better structured walls was observed for 167 J/cm3. Furthermore, it was determined that at an energy density of 6.9 KJ/mol a higher purification of MWCNTs is obtained. This value is in agreement with the enthalpy of formation reported for the MWCNTs. This experimental approach could be applied for the functionalization of carbon nanostructures. Finally, the purification process is easily scalable, environmentally friendly and makes maximum use of the irradiated energy. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

227. Alkaloids in the Mite Scheloribates laevigatus: Further Alkaloids Common to Oribatid Mites and Poison Frogs.

Author

Saporito, Ralph A., Norton, Roy A., Andriamaharavo, Nirina R., Garraffo, Hugo Martin, and Spande, Thomas F.

Subjects
ALKALOIDS, MITES, DENDROBATIDAE, POISONOUS animals, FROGS
Abstract

Poison frogs are chemically defended from predators by diverse alkaloids, almost all of which are sequestered unchanged from alkaloid-containing arthropods in the frog diet. Oribatid mites recently have been proposed as a major dietary source of poison frog alkaloids. Here, we report on alkaloids common to an oribatid mite and poison frogs. Gas chromatographic-mass spectrometric analysis of methanol extracts of adult Scheloribates laevigatus (Oribatida: Scheloribatidae) revealed nine alkaloids. Five of these have been detected previously in the skin glands of poison frogs: two isomers of the pumiliotoxin 291G, two isomers of the 5,6,8-trisubstituted indolizidine 209C, and the 5,6,8-trisubstituted indolizidine 195G. The other four alkaloids, a pumiliotoxin, a tricyclic (coccinelline-like), and two isomers of an izidine, were not previously known, but are similar in structure to alkaloids found in poison frogs. Alkaloids were not detected in immature S. laevigatus, suggesting that they are adult-specific and possibly the result of mite biosynthesis. Although most of the alkaloids detected in S. laevigatus are common to poison frogs, the geographic distributions of these organisms are not sympatric. The findings of this study indicate that oribatid mites, and in particular, members of the genus Scheloribates, represent a relatively unexplored arthropod repository for alkaloids and a significant dietary source of alkaloids in poison frogs. [ABSTRACT FROM AUTHOR]

Published
2011
Full Text
View/download PDF

228. Contribution by different marine bacterial communities to particulate beam attenuation.

Author

Montes-Hugo, Martin A., Ducklow, Hugh, and Schofield, Oscar M.

Subjects
HETEROTROPHIC bacteria, MASS attenuation coefficients, MARINE bacteria, MAGNITUDE estimation, LIGHT scattering, MIE scattering, LIFE zones, BIOMASS estimation
Abstract

The article presents a study which investigates the involvement of heterotrophic marine bacteria (HB) in oceanic regions to the particulate beam attenuation coefficient (cp) magnitude and variability. It calculates the number of HB in oceanic regions through surface measurements of bacterial abundance, physio-optical empirical relationships, and light scattering models. It was found that the involvement of HB to cp was not dominant and cp response to HB concentrations was indirect. It suggests that though there were possible restrictions in HB biomass-dependent parameters estimation, the averaged cHB/cp values can be used as an ecological index for the discrimination of biogeographic regions with different dynamics of particles.

Published
2009
Full Text
View/download PDF

229. Recent Changes in Phytoplankton Communities Associated with Rapid Regional Climate Change Along the Western Antarctic Peninsula.

Author

Montes-Hugo, Martin, Doney, Scott C., Ducklow, Hugh W., Fraser, William, Martinson, Douglas, Stammerjohn, Sharon E., and Schofield, Oscar

Subjects
*PHYTOPLANKTON populations, *CLIMATE change, *CLIMATE change research, *ARTIFICIAL satellites in earth sciences, *FIELD research, *DATA analysis, *CHLOROPHYLL, *ICE sheets
Abstract

The climate of the western shelf of the Antarctic Peninsula (WAP) is undergoing a transition from a cold-dry polar-type climate to a warm-humid sub-Antarctic-type climate. Using three decades of satellite and field data, we document that ocean biological productivity, inferred from chlorophyll a concentration (Chl a), has significantly changed along the WAP shelf. Summertime surface Chl a (summer integrated Chl a -63% of annually integrated Chl a) declined by 12% along the WAP over the past 30 years, with the largest decreases equatorward of 63°S and with substantial increases in Chl a occurring farther south. The latitudinal variation in Chl a trends reflects shifting patterns of ice cover, cloud formation, and windiness affecting water-column mixing. Regional changes in phytoplankton coincide with observed changes in krill (Euphausia superba) and penguin populations. [ABSTRACT FROM AUTHOR]

Published
2009
Full Text
View/download PDF

230. Horizontal Sighting Range and Secchi Depth as Estimators of Underwater PAR Attenuation in a Coastal Lagoon.

Author

Montes-Hugo, Martin A., Alvarez-Borrego, Saul, and Giles-Guzman, Alma D.

Abstract

Attenuation of photosynthetically available radiation (PAR) measured using a light meter, was related to Secchi disk, horizontal black disk and horizontal sighting ranges observed in a coastal lagoon of the Southern California Current System. Vertical attenuation coefficient (K[sub PAR]) was calculated from radiometric PAR profiles. Vertical (Z[sub D]) and horizontal (HS) sighting ranges were measured with white (Secchi depth or Z[sub SD], HS[sub w]) and black (Z[sub BD], HS[sub B]) targets. Empirical power models for the K[sub PAR]-Z[sub SD] (K[sub PAR] = 1.47 Z[sub SD, sup -1.13]), K[sub PAR-Z[sub BD] (K[sub PAR = 0.98 Z[sub BD, sup -1.26]), K[sub PAR] - HS[sub W] (K[sub PAR] = 1.22 HS[sub W, sup -1.14]), and K[sub PAR] - HS[sub B] (K[sub PAR] = 0.73 HS[sub B, sup -1.07]) relationships were developed. The parameters of these models may not apply to other water bodies because their values depend on the range of water reflectance in each case, as reported in the literature. This is the first contribution reporting K[sub PAR]-HS empirical relations in an estuarine environment but their application may be limited to this coastal lagoon. While this approach may be universal, more data are needed to explore the variability of the parameters between different water bodies. [ABSTRACT FROM AUTHOR]

Published
2003
Full Text
View/download PDF

233. Aillu: sistema de botiquín comunitario de atención primaria para la promoción y prevención sanitaria en la población de Cochabamba, Áncash

Author

Fiestas Urbina, Hugo Martin and Fiestas Urbina, Hugo Martin

Abstract

La Atención Primaria de Salud ofrece tratamiento y medicación básica a la población, asimismo, promueve el cuidado de su salud al brindarles información sobre cómo prevenir afecciones. Sin embargo, su acceso en comunidades rurales como Cochabamba, en el departamento de Áncash, es limitado y genera ineficacia en la promoción de la salud y prevención de enfermedades. En este contexto, el botiquín representa una herramienta fundamental de primeros auxilios, cuyo estudio guio esta investigación con un enfoque de Diseño Social, Emocional y Participativo. Su diseño actual se orienta a innovaciones técnicas y funcionales con productos de similar morfología, donde la organización de medicamentos e insumos de primeros auxilios es primordial. No obstante, se limitan casi exclusivamente al tratamiento de emergencia y solo apoyan la atención primaria superficialmente. Este estudio plantea el diseño del Sistema de Botiquín Comunitario Aillu, que brinda atención primaria accesible, y facilita la promoción sanitaria y prevención de enfermedades respiratorias y digestivas. Para validarlo, se realizó una serie de entrevistas a distancia bajo la metodología del Diseño Centrado en el Humano, apoyada por enfoques sociales y emocionales. Asimismo, se planteó una validación a distancia con métodos etnográficos y netnográficos. La información recopilada se organizó por medio de tablas de registro y se analizó a través de mapas de empatía y un diagrama de afinidad. Estos brindaron parámetros de diseño y mostraron el interés local de participar en la salud comunitaria, donde Aillu les brinda las herramientas para involucrarse en la Atención Primaria de Salud, les permite ser protagonistas de la promoción sanitaria e incentiva su participación activa. Por ello, se espera que el Sistema Aillu cree un vínculo de cooperación con el centro médico que permita desarrollar la autogestión comunitaria de su salud básica., Primary Health Care offers treatment and basic medication to the population, likewise, it promotes their health care by providing them with information on how to prevent diseases. However, its access in rural communities such as Cochabamba, in the department of Ancash, is limited and generates ineffectiveness in health promotion and disease prevention. In this context, the first aid kit represents a fundamental first aid tool, and its study guided this research with a Social, Emotional and Participatory Design approach. Its current design is oriented towards technical and functional innovations with products of similar morphology, where the organization of medicines and first aid supplies is essential. However, they are almost exclusively limited to emergency treatment and only superficially support primary care. This study proposes the design of the Aillu Community Health Kit System, which provides accessible primary care, and facilitates health promotion and prevention of respiratory and digestive diseases. To validate it, a series of distance interviews was carried out under the Human Centered Design methodology, supported by social and emotional approaches. Likewise, a remote validation with ethnographic and netnographic methods was proposed. The information collected was organized through registration tables and analyzed through empathy maps and an affinity diagram. These provided design parameters and showed local interest in participating in community health, where Aillu provides them with the tools to get involved in Primary Health Care, allows them to be protagonists of health promotion and encourages their active participation. For this reason, it is expected that the Aillu System will create a cooperative link with the medical center that will allow them to develop community self-management of their basic health.

234. Fisioten: Sistema Integral de Fisioterapia para Pacientes con Tendinitis

Author

Loaiza Soracco, Renato Gonzalo, Fiestas Urbina, Hugo Martin, Loaiza Soracco, Renato Gonzalo, and Fiestas Urbina, Hugo Martin

Abstract

En el Perú hay alrededor de 49000 pacientes que reciben fisioterapia por discapacidad motora, pero esto solo representa el 5.25% de los afectados. El tratamiento de tendinitis es fundamental y debe realizarse con constancia. Para ello, se desarrollan protocolos de técnicas mixtas que involucran diversas sesiones fisioterapéuticas; sin embargo, estos procedimientos no son integrados para diferentes áreas afectadas, requieren de atención especializada y dependen de la capacidad física de los pacientes. Mediante este estudio se propone el Fisioten, un sistema integral de fisioterapia de tendinitis compuesto de técnicas de rehabilitación para hombro, rodilla y tendón, en una misma estación; que no solo facilita la labor del profesional médico, sino que permite al paciente manejar su tratamiento independientemente, de forma práctica e inclusiva. Se utilizaron herramientas observacionales y encuestas para definir los requerimientos necesarios con los que se desarrolló el modelo conceptual, que luego fue validado a partir de opiniones de expertos sobre su practicidad y eficacia en la fisioterapia de tendinitis. Fisioten brinda a sus usuarios la capacidad de realizar múltiples técnicas de fisioterapia sin la necesidad de asistir a distintas citas de atención médica, y la posibilidad de continuar la rehabilitación en la comodidad del hogar.

235. Aillu: sistema de botiquín comunitario de atención primaria para la promoción y prevención sanitaria en la población de Cochabamba, Áncash

Author

Fiestas Urbina, Hugo Martin and Fiestas Urbina, Hugo Martin

Abstract

La Atención Primaria de Salud ofrece tratamiento y medicación básica a la población, asimismo, promueve el cuidado de su salud al brindarles información sobre cómo prevenir afecciones. Sin embargo, su acceso en comunidades rurales como Cochabamba, en el departamento de Áncash, es limitado y genera ineficacia en la promoción de la salud y prevención de enfermedades. En este contexto, el botiquín representa una herramienta fundamental de primeros auxilios, cuyo estudio guio esta investigación con un enfoque de Diseño Social, Emocional y Participativo. Su diseño actual se orienta a innovaciones técnicas y funcionales con productos de similar morfología, donde la organización de medicamentos e insumos de primeros auxilios es primordial. No obstante, se limitan casi exclusivamente al tratamiento de emergencia y solo apoyan la atención primaria superficialmente. Este estudio plantea el diseño del Sistema de Botiquín Comunitario Aillu, que brinda atención primaria accesible, y facilita la promoción sanitaria y prevención de enfermedades respiratorias y digestivas. Para validarlo, se realizó una serie de entrevistas a distancia bajo la metodología del Diseño Centrado en el Humano, apoyada por enfoques sociales y emocionales. Asimismo, se planteó una validación a distancia con métodos etnográficos y netnográficos. La información recopilada se organizó por medio de tablas de registro y se analizó a través de mapas de empatía y un diagrama de afinidad. Estos brindaron parámetros de diseño y mostraron el interés local de participar en la salud comunitaria, donde Aillu les brinda las herramientas para involucrarse en la Atención Primaria de Salud, les permite ser protagonistas de la promoción sanitaria e incentiva su participación activa. Por ello, se espera que el Sistema Aillu cree un vínculo de cooperación con el centro médico que permita desarrollar la autogestión comunitaria de su salud básica., Primary Health Care offers treatment and basic medication to the population, likewise, it promotes their health care by providing them with information on how to prevent diseases. However, its access in rural communities such as Cochabamba, in the department of Ancash, is limited and generates ineffectiveness in health promotion and disease prevention. In this context, the first aid kit represents a fundamental first aid tool, and its study guided this research with a Social, Emotional and Participatory Design approach. Its current design is oriented towards technical and functional innovations with products of similar morphology, where the organization of medicines and first aid supplies is essential. However, they are almost exclusively limited to emergency treatment and only superficially support primary care. This study proposes the design of the Aillu Community Health Kit System, which provides accessible primary care, and facilitates health promotion and prevention of respiratory and digestive diseases. To validate it, a series of distance interviews was carried out under the Human Centered Design methodology, supported by social and emotional approaches. Likewise, a remote validation with ethnographic and netnographic methods was proposed. The information collected was organized through registration tables and analyzed through empathy maps and an affinity diagram. These provided design parameters and showed local interest in participating in community health, where Aillu provides them with the tools to get involved in Primary Health Care, allows them to be protagonists of health promotion and encourages their active participation. For this reason, it is expected that the Aillu System will create a cooperative link with the medical center that will allow them to develop community self-management of their basic health.

236. Fisioten: Sistema Integral de Fisioterapia para Pacientes con Tendinitis

Author

Loaiza Soracco, Renato Gonzalo, Fiestas Urbina, Hugo Martin, Loaiza Soracco, Renato Gonzalo, and Fiestas Urbina, Hugo Martin

Abstract

En el Perú hay alrededor de 49000 pacientes que reciben fisioterapia por discapacidad motora, pero esto solo representa el 5.25% de los afectados. El tratamiento de tendinitis es fundamental y debe realizarse con constancia. Para ello, se desarrollan protocolos de técnicas mixtas que involucran diversas sesiones fisioterapéuticas; sin embargo, estos procedimientos no son integrados para diferentes áreas afectadas, requieren de atención especializada y dependen de la capacidad física de los pacientes. Mediante este estudio se propone el Fisioten, un sistema integral de fisioterapia de tendinitis compuesto de técnicas de rehabilitación para hombro, rodilla y tendón, en una misma estación; que no solo facilita la labor del profesional médico, sino que permite al paciente manejar su tratamiento independientemente, de forma práctica e inclusiva. Se utilizaron herramientas observacionales y encuestas para definir los requerimientos necesarios con los que se desarrolló el modelo conceptual, que luego fue validado a partir de opiniones de expertos sobre su practicidad y eficacia en la fisioterapia de tendinitis. Fisioten brinda a sus usuarios la capacidad de realizar múltiples técnicas de fisioterapia sin la necesidad de asistir a distintas citas de atención médica, y la posibilidad de continuar la rehabilitación en la comodidad del hogar.

237. Aillu: sistema de botiquín comunitario de atención primaria para la promoción y prevención sanitaria en la población de Cochabamba, Áncash

Author

Fiestas Urbina, Hugo Martin and Fiestas Urbina, Hugo Martin

Abstract

La Atención Primaria de Salud ofrece tratamiento y medicación básica a la población, asimismo, promueve el cuidado de su salud al brindarles información sobre cómo prevenir afecciones. Sin embargo, su acceso en comunidades rurales como Cochabamba, en el departamento de Áncash, es limitado y genera ineficacia en la promoción de la salud y prevención de enfermedades. En este contexto, el botiquín representa una herramienta fundamental de primeros auxilios, cuyo estudio guio esta investigación con un enfoque de Diseño Social, Emocional y Participativo. Su diseño actual se orienta a innovaciones técnicas y funcionales con productos de similar morfología, donde la organización de medicamentos e insumos de primeros auxilios es primordial. No obstante, se limitan casi exclusivamente al tratamiento de emergencia y solo apoyan la atención primaria superficialmente. Este estudio plantea el diseño del Sistema de Botiquín Comunitario Aillu, que brinda atención primaria accesible, y facilita la promoción sanitaria y prevención de enfermedades respiratorias y digestivas. Para validarlo, se realizó una serie de entrevistas a distancia bajo la metodología del Diseño Centrado en el Humano, apoyada por enfoques sociales y emocionales. Asimismo, se planteó una validación a distancia con métodos etnográficos y netnográficos. La información recopilada se organizó por medio de tablas de registro y se analizó a través de mapas de empatía y un diagrama de afinidad. Estos brindaron parámetros de diseño y mostraron el interés local de participar en la salud comunitaria, donde Aillu les brinda las herramientas para involucrarse en la Atención Primaria de Salud, les permite ser protagonistas de la promoción sanitaria e incentiva su participación activa. Por ello, se espera que el Sistema Aillu cree un vínculo de cooperación con el centro médico que permita desarrollar la autogestión comunitaria de su salud básica., Primary Health Care offers treatment and basic medication to the population, likewise, it promotes their health care by providing them with information on how to prevent diseases. However, its access in rural communities such as Cochabamba, in the department of Ancash, is limited and generates ineffectiveness in health promotion and disease prevention. In this context, the first aid kit represents a fundamental first aid tool, and its study guided this research with a Social, Emotional and Participatory Design approach. Its current design is oriented towards technical and functional innovations with products of similar morphology, where the organization of medicines and first aid supplies is essential. However, they are almost exclusively limited to emergency treatment and only superficially support primary care. This study proposes the design of the Aillu Community Health Kit System, which provides accessible primary care, and facilitates health promotion and prevention of respiratory and digestive diseases. To validate it, a series of distance interviews was carried out under the Human Centered Design methodology, supported by social and emotional approaches. Likewise, a remote validation with ethnographic and netnographic methods was proposed. The information collected was organized through registration tables and analyzed through empathy maps and an affinity diagram. These provided design parameters and showed local interest in participating in community health, where Aillu provides them with the tools to get involved in Primary Health Care, allows them to be protagonists of health promotion and encourages their active participation. For this reason, it is expected that the Aillu System will create a cooperative link with the medical center that will allow them to develop community self-management of their basic health.

238. Fisioten: Sistema Integral de Fisioterapia para Pacientes con Tendinitis

Author

Loaiza Soracco, Renato Gonzalo, Fiestas Urbina, Hugo Martin, Loaiza Soracco, Renato Gonzalo, and Fiestas Urbina, Hugo Martin

Abstract

En el Perú hay alrededor de 49000 pacientes que reciben fisioterapia por discapacidad motora, pero esto solo representa el 5.25% de los afectados. El tratamiento de tendinitis es fundamental y debe realizarse con constancia. Para ello, se desarrollan protocolos de técnicas mixtas que involucran diversas sesiones fisioterapéuticas; sin embargo, estos procedimientos no son integrados para diferentes áreas afectadas, requieren de atención especializada y dependen de la capacidad física de los pacientes. Mediante este estudio se propone el Fisioten, un sistema integral de fisioterapia de tendinitis compuesto de técnicas de rehabilitación para hombro, rodilla y tendón, en una misma estación; que no solo facilita la labor del profesional médico, sino que permite al paciente manejar su tratamiento independientemente, de forma práctica e inclusiva. Se utilizaron herramientas observacionales y encuestas para definir los requerimientos necesarios con los que se desarrolló el modelo conceptual, que luego fue validado a partir de opiniones de expertos sobre su practicidad y eficacia en la fisioterapia de tendinitis. Fisioten brinda a sus usuarios la capacidad de realizar múltiples técnicas de fisioterapia sin la necesidad de asistir a distintas citas de atención médica, y la posibilidad de continuar la rehabilitación en la comodidad del hogar.

239. Accumulation of polyubiquitinated proteins: A consequence of early inactivation of the 26S proteasome.

Author

Reeg, Sandra, Castro, José P., Hugo, Martin, and Grune, Tilman

Subjects
*PROTEASOMES, *PROTEOLYSIS, *PROTEINS, *OXIDATIVE stress, *UBIQUITINATION
Abstract

The proteasomal degradation system is one of the most important protein degradation systems in the cytosol and nucleus. This system is present in two major forms: the ATP-stimulated 26S/30 S proteasome or the ATP-independent 20S core proteasome. While the first recognize ubiquitin-tagged target proteins and degrade them, the 20S proteasome works also independent from ATP, but requires partially unfolded substrates. While the role of the proteasome in the selective removal of oxidized proteins is undoubted, the debate about a selective ubiquitination of oxidized proteins is still ongoing. Here we demonstrate, that under some conditions of oxidative stress an accumulation of oxidized and of K48-ubiquitinated proteins occurs. However, the removal of oxidized proteins seems not to be linked to ubiquitination. In further experiments, we could show that the accumulation of ubiquitinated proteins under certain oxidative stress conditions is rather a result of a different sensitivity of the 26S proteasome and the ubiquitination machinery towards oxidants. Image 1 • Oxidative stress leads to a temporary presence of K48-polyubiquitinated proteins. • Polyubiquitination of proteins after oxidative stress is not selective for oxidized proteins. • The 26S proteasome has a higher sensitivity towards oxidative inactivation, compared to the ubiquitination machinery. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

240. Retired ocean liner begins spooky special effects tour.

Author

Hugo Martin

Abstract

LOS ANGELES - The Queen Mary, a retired ocean liner that has become a floating hotel in the Long Beach harbor, has turned to the type of special effects made famous in Hollywood to try to boost visitor numbers. [ABSTRACT FROM PUBLISHER]

Published
2017

246. Síntesis de adsorbentes a partir de subproductos microparticulados de la actividad minera de cantera

Author

Castillo Rodriguez, Ferley Yussef and Galindo Valvuena, Hugo Martin

Subjects
541 - Química física [540 - Química y ciencias afines], 622 - Minería y operaciones relacionadas [620 - Ingeniería y operaciones afines], Zeolite, 546 - Química inorgánica [540 - Química y ciencias afines], Hydrolysis, Aluminum silicates, Zeolite industry, Waste mining, 549 - Mineralogía [540 - Química y ciencias afines], Catalysis, Silicatos de aluminio, Zeolitas, Cristalización, Industria de la zeolita, Hidrolisis, Adsorption, Catálisis, Crystallization, Residuos mineros, Adsorción
Abstract

ilustraciones, fotografías Las actividades de explotación minera de cantera a cielo abierto para la producción de agregados para la industria de la construcción producen un subproducto microparticulado que hasta ahora no presentan aplicaciones económicas ni tecnológicas viables. La distribución de tamaño de partícula de este subproducto impide su aplicación en la formulación de concretos. La carencia de aplicaciones para este material particulado ha llevado a su clasificación como residuo sólido, cuya disposición final es la apilado a cielo abierto; debido a este apilamiento, las partículas sólidas son dispersadas fácilmente por corrientes de aire y aguas lluvias, impactando negativamente fuentes hídricas, suelos, vegetación y establecimientos urbanos alrededor del lugar de disposición final del material. Atendiendo a la problemática ambiental generada por estos sólidos y su disposición final, esta investigación se planteó el objetivo de desarrollar procesos de conversión que permitan transformar a este residuo en materiales con aplicaciones tecnológicas tales como zeolitas. El sólido, denominado usualmente como fino de cantera o fino producido en la molienda de roca de cantera, es una mezcla de arcillas, cuarzo, materia orgánica y pedazos de vidrio, plásticos y metales. El uso de este microparticulado en procesos de conversión físicoquímicos permitirá posicionar a este sólido como una materia prima de bajo costo para síntesis inorgánicas. Así mismo, la percepción de los finos como materia prima se ajusta a los preceptos de la economía circular. El proceso de conversión del fino de cantera está basado en una hidrólisis alcalina hidrotérmica que produce un material sólido además de silicatos solubles. El producto sólido de la hidrólisis, que es el de interés en esta investigación, fue identificado como la zeolita analcima mediante difracción de rayos X. 3 g de zeolita son obtenidos a partir de 12 g de fino de cantera durante el tratamiento hidrotérmico. La zeolita analcima fue empleada en esta tesis como precursor de procesos hidrotérmicos de activación alcalinos y ácidos que buscaron potenciar su capacidad de retención de adsorbatos en procesos de adsorción. Las condiciones empleadas para las activaciones usaron diferentes ácidos y mezclas de estos, así como diferentes bases y mezclas. Las activaciones con diferentes sistemas alcalinos y básicos fueron promovidas por la actividad diferencial que presentan los ácidos o bases en los procesos de remoción de aluminio o silicio de la estructura del precursor. (Texto tomado de la fuente) The exploitation of open-pit quarries for the production of aggregates used in the construction industry produces microparticulated wastes that so far have no viable economic or technological applications. The particle size distribution of this by-product prevents its application in the concrete formulation. The lack of applications for these particulate matter determines them as solid waste, the final disposal of which is open piles; due to this stacking, the solid particles are easily dispersed by air currents, rainwater, negatively impacting water sources, solids vegetation and urban places around the place of final disposal of the material. Attending to the environmental problems generated by these solids and their final disposal, this research it was proposed to develop conversion processes allow modified this waste in to materials with technological applications such as adsorption. The solid, usually called quarry fines or fines produced in the grinding of quarry rock, is a mixture of clays, quartz, organic matter and pieces of glass, plastics and metals. The use of this microparticle in physicochemical conversion processes will allow this solid to be positioned it as a raw material of low cost for organic synthesis. Likewise, the perception of quarry fines as a raw material is in line with the precepts of the circular economy. The quarry fine conversion process is based on a hydrothermal alkaline hydrolysis that produces a solid material in addition soluble silicates. The solid product of hydrolysis, which is of interest in this research, was identified as analcime zeolite by X-ray diffraction. from 12 g of treated fine quarry solids, three grams of solid product are obtained during the hydrothermal process. Analcime zeolite was used in this research as a precursor for alkaline and acid hydrothermal activation processes that sought to enhance its adsorbate retention capacity in adsorption processes. The conditions used the activation used different acids and mixtures of these, as well as different bases and mixtures of these. The activations whit different alkaline and basic system were promoted by the different activity that the acids or bases present in the aluminum or silicon removal processes from the precursor framework Maestría Conversión físico química de residuos mineros

Published
2023

247. Decadal variability in coastal phytoplankton community composition in a changing West Antarctic Peninsula.

Author

Schofield, Oscar, Saba, Grace, Coleman, Kaycee, Carvalho, Filipa, Couto, Nicole, Ducklow, Hugh, Finkel, Zoe, Irwin, Andrew, Kahl, Alex, Miles, Travis, Montes-Hugo, Martin, Stammerjohn, Sharon, and Waite, Nicole

Subjects
*ALGAL blooms, *PHYTOFLAGELLATES, *TERRITORIAL waters, *FOOD chains
Abstract

The coastal waters of the West Antarctic Peninsula (WAP) are associated with large phytoplankton blooms dominated by large (>20 µm) diatoms however, nanoplankton (<20 µm) are also an important component of the food web. The dominant nanoflagellates in the WAP are cryptomonad algae. Using a twenty-year time series collected by the Palmer Long Term Ecological Research program at the United States Palmer Research Station, we assessed long-term patterns and stability in the coastal phytoplankton communities in the WAP. There was significant interannual variability in the integrated water column chlorophyll a (chl- a ) concentrations, which varied by a factor of 5 over the 20-year time series. There has been a significant positive increase in the seasonally integrated concentration of chl- a over the time series. The dominant phytoplankton were diatoms, with cryptophytes the second most abundant. Mixed flagellates also constituted a significant fraction of the chl- a but showed less inter a nnual variability than diatoms and cryophytes. Peak phytoplankton biomass was observed in summer months, when monthly averaged wind speed was lower than in the fall and autumn. Cryptophytes were most abundant during the summer months (December-January) after the seasonal retreat of sea ice. While diatoms were observed over the full range of observed salinities 32–34.5) as well as over the full range of in situ temperatures (−1.5 to 2.5 °C), the cryptophyte populations were observed in locations with lower salinity 32.5–33.75) and colder water (−1 to 1 °C). Environmental factors that favored a shallower seasonal mixed layer resulted in larger diatom blooms compared to the other phytoplankton taxa. During summer with lower phytoplankton biomass, a larger proportion of the chlorophyll a was associated with cryptophytes. These results demonstrate that continued temperature changes along the West Antarctic Peninsula will result in changes in phytoplankton concentration and community composition, which has significant ramifications for the food web. [ABSTRACT FROM AUTHOR]

Published
2017
Full Text
View/download PDF

248. Inclusion through folk high school in Sweden - the experience of young adult students with high-functioning autism.

Author

Hugo M and Hedegaard J

Subjects
Humans, Qualitative Research, Schools, Students, Sweden, Young Adult, Academic Success, Autistic Disorder
Abstract

Purpose: The purpose of this study is to provide a description of the learning environment at Folk High School for participants with high-functioning autism and to examine their learning experience at Folk High School., Methods: A qualitative interview study was conducted with 21 participants who were enrolled at Folk High School which had been adapted to suit young adults with high-functioning autism. The interviews were analysed by means of a thematic content analysis which resulted in the identification of 6 themes related to learning experiences at Folk High School., Results: The participants enjoyed themselves and felt secure at Folk High School. They felt that they and their academic endeavours were suitably recognised, acknowledged, and understood. They reported that the teaching was suitably adapted for them and they felt that they could succeed in their studies. A frequent report that they made concerned their experience of clear structures in the teaching process and its predictability. The participants stated that Folk High School has the ability to satisfy each participant's needs, which entailed lower levels of perceived stress than what they had experienced in their previous schooling. The participants experienced personal development during their time at Folk High School., Conclusions: Folk High School, and its special character, is able to successfully satisfy the needs of participants with high-functioning autism. Many of the participants, for the first time in their lives, experienced a sense of inclusion in an educational system and felt that they could succeed in their studies. However, there exists a risk that they become institutionalised, which entails that the participants function well primarily in Folk High School's safe and caring environment.Implications for rehabilitationA supportive environment including both formal and social learning is paramount for people with high-functioning autism.Individually adapted teaching that is structured and predictable improve the conditions under which they can focus on their studies and enjoy academic success.The teachers' relational competence and ability to show interest in each individual are crucial.Social- and special-pedagogic competencies need to co-exist so as to improve learning conditions.Internship/workplace training can provide an important social learning experience for participants, as they learn about themselves and others and as they develop their social competence.To practice living on one's own is a significant challenge, but it can create opportunities to learn about one's self and to develop a sense of responsibility and other social skills.

Published
2021
Full Text
View/download PDF

249. Happily (n)ever after: Aging in the context of oxidative stress, proteostasis loss and cellular senescence.

Author

Höhn A, Weber D, Jung T, Ott C, Hugo M, Kochlik B, Kehm R, König J, Grune T, and Castro JP

Subjects
Aging metabolism, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 metabolism, Diabetes Mellitus, Type 2 pathology, Humans, Neoplasms genetics, Neoplasms metabolism, Neoplasms pathology, Oxidants metabolism, Aging genetics, Antioxidants metabolism, Cellular Senescence genetics, Oxidative Stress genetics
Abstract

Aging is a complex phenomenon and its impact is becoming more relevant due to the rising life expectancy and because aging itself is the basis for the development of age-related diseases such as cancer, neurodegenerative diseases and type 2 diabetes. Recent years of scientific research have brought up different theories that attempt to explain the aging process. So far, there is no single theory that fully explains all facets of aging. The damage accumulation theory is one of the most accepted theories due to the large body of evidence found over the years. Damage accumulation is thought to be driven, among others, by oxidative stress. This condition results in an excess attack of oxidants on biomolecules, which lead to damage accumulation over time and contribute to the functional involution of cells, tissues and organisms. If oxidative stress persists, cellular senescence is a likely outcome and an important hallmark of aging. Therefore, it becomes crucial to understand how senescent cells function and how they contribute to the aging process. This review will cover cellular senescence features related to the protein pool such as morphological and molecular hallmarks, how oxidative stress promotes protein modifications, how senescent cells cope with them by proteostasis mechanisms, including antioxidant enzymes and proteolytic systems. We will also highlight the nutritional status of senescent cells and aged organisms (including human clinical studies) by exploring trace elements and micronutrients and on their importance to develop strategies that might increase both, life and health span and postpone aging onset., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results