El Estudio caracteriza y actualiza la fauna silvestre vertebrada de la Península de<br> Cos... more El Estudio caracteriza y actualiza la fauna silvestre vertebrada de la Península de<br> Cosigüina, evaluando los elementos ambientales y sociales en que esta se<br> desarrolla, identificando en el proceso las amenazas a la biodiversidad y opciones<br> de conservación. Analizamos los resultados faunísticos de muchas de las<br> "Evaluación de campo" conocidas para la reserva, incluyendo datos históricos. Esta<br> zona presenta una variedad de hábitats típicos de Pacífico nicaragüense,<br> sobresaliendo una importante cobertura vegetal de bosque seco alrededor del<br> volcán (con su laguna cratérica al fondo), así como una amplia zona marinocostera<br> con pequeños parches de esteros y manglares; que en conjunto abrigan<br> poblaciones faunísticas esenciales para el equilibrio ecológico de la zona y de las<br> poblaciones humanas. En total se registran 305 especies de fauna silvestre<br> vertebrada (no ictiológ...
This is a study of the experiences of Latina garment workers and their mostly white managers. It ... more This is a study of the experiences of Latina garment workers and their mostly white managers. It is a women-centered analysis of the social practices at work and at home. As such, the research departs from the structural accounts of the garment industry which portray Latina garment workers as objects who are part of an economic process that tend to erase their lived experiences. Using field site observations at a denim contracting shop and in-depth interviews with Latina garment workers and their managers, I link their personal account of work to how gender, ethnicity, and immigration status impact work. In Los Angeles, Latinas continue to make-up the majority of garment workers. Through their voices we learn the reasons why they entered in the garment industry, why they stay in this exploitative field, and some of the ways they resist their exploitation. Their voices challenge the old myths that garment work takes little skill to master. These women recount their everyday experienc...
Revista Latinoamericana De Metalurgia Y Materiales, Dec 9, 2013
Three materials were deposited on AISI-SAE 4340 steel using the wire arc thermal spray technique.... more Three materials were deposited on AISI-SAE 4340 steel using the wire arc thermal spray technique. The deposited materials are commercially known as 140MXC (Fe, Nb, Cr, W), 530AS, which is a steel similar to AISI-SAE 1015, and 560AS, which is a steel similar to AISI-SAE 420. With the aim of evaluating the best strategy for increasing the corrosion resistance in the coating-substrate system, the coatings were deposited in three different ways: (1) homogeneous monolayers (single layers) of each material, (2) (Double layer) bilayers composed of a monolayer of 140MXC over a monolayer of either 530AS or 560AS, and (3) simultaneous monolayertype (single layer) coatings achieved by depositing 140MXC + 530AS in the first case and 140MXC + 560AS in the second case. The coatings were characterized by optical microscopy and X-ray diffraction. The corrosion resistance was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization. The resistance to polarization of the material deposited in bilayers was increased through the congestion of defects with corrosion products, while the simultaneous monolayers achieved increased corrosion resistance by the reduction of defects with respect to 140MXC. The details and mechanisms of corrosion in the fabricated coatings are described in this study.
Síntesis y caracterización de polvos de dióxido de estaño dopado con hierro (Sn (1-x) Fe x o 2) p... more Síntesis y caracterización de polvos de dióxido de estaño dopado con hierro (Sn (1-x) Fe x o 2) para la preparación de películas delgadas Synthesis and characterization of powders of tin dioxide doped with iron (Sn (1-x) Fe x o 2) for the preparation of thin films López, E. I ; Marín, J. I y Osorio, J. II Resumen. En este trabajo se establecen las condiciones apropiadas para la síntesis de polvos SnO 2 dopado con hierro al 10% a través de la ruta sol-gel. La caracterización de los polvos obtenidos por este método se realiza mediante la aplicación de diferentes técnicas espectroscópicas como Mössbauer e infrarroja por transformada de Fourier, así como por difracción de rayos X.
Cadmium plating on metal surfaces is commonly used for corrosion protection and to achieve good s... more Cadmium plating on metal surfaces is commonly used for corrosion protection and to achieve good solderability on the 304L stainless steel shell of the MC4636 lightning arrestor connector (LAC) for the W76-1 system. This study examined the use of zinc as a potential substitute for the cadmium protective surface finish. Tests were performed with an R and RMA flux and test temperatures of 230ºC, 245ºC, and 260ºC. Contact angle, θ C , served as the generalized solderability metric. The wetting rate and wetting time parameters were also collected. The solderability (θ C) of the Erie Plating Cd/Ni coatings was better than that of similar Amphenol coatings. Although the θ C data indicated that both Cd/Ni platings would provide adequate solderability, the wetting rate and wetting time data showed the Amphenol coatings to have better performance. The Zn/Ni coatings exhibited non-wetting under all flux and temperature conditions. Based on the results of these tests, it has been demonstrated that zinc plating is not a viable alternate to cadmium plating for the LAC connectors 1 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Dept. of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. Contents Pg. Tables iv 1.
Portions of this document may be iiiegible in electronic image products. images are produced from... more Portions of this document may be iiiegible in electronic image products. images are produced from the best avaiiabie originai document. .
1 See Makowski & Ostroy (2001) and Gale (2000) for two essential references on the recent literat... more 1 See Makowski & Ostroy (2001) and Gale (2000) for two essential references on the recent literature about the reestablishment of the perfect competition framework within a strategic behaviour approach as an alternative view regarding the traditional price-taker hypothesis.
Resumo: Con la finalidad de evaluar las propiedades dietéticas de dos fórmulas, una a base de car... more Resumo: Con la finalidad de evaluar las propiedades dietéticas de dos fórmulas, una a base de carne de pollo y la otra ADN (Alimentos Dietético Nutricional elaborado por Laboratorios Davis SA Chile), se reviso 146 expedientes de niños desnutridos severos, ...
The Energy Citations Database (ECD) provides access to historical and current research (1948 to t... more The Energy Citations Database (ECD) provides access to historical and current research (1948 to the present) from the Department of Energy (DOE) and predecessor agencies.
The Energy Citations Database (ECD) provides access to historical and current research (1948 to t... more The Energy Citations Database (ECD) provides access to historical and current research (1948 to the present) from the Department of Energy (DOE) and predecessor agencies.
Objective. To develop a rapid, easy and clinically relevant in vivo model to evaluate novel insul... more Objective. To develop a rapid, easy and clinically relevant in vivo model to evaluate novel insulin secretagogues on human islets, we investigated the effect of insulin secretagogues on functional human islets in a humanized mouse model. Materials/Methods. Human islets were transplanted under the kidney capsule of streptozotocin (STZ)-induced diabetic mice with immunodeficiency. Human islet graft function was monitored by measuring non-fasting blood glucose levels. After diabetes was reversed, human islet transplanted mice were characterized physiologically by oral glucose tolerance and pharmacologically with clinically proven insulin secretagogues, glucagon-like peptide-1 (GLP-1), exenatide, glyburide, nateglinide and sitagliptin. Additionally, G protein-coupled receptor 40 (GPR40) agonists were evaluated in this model. Results. Long-term human islet graft survival could be achieved in immunodeficient mice. Oral glucose challenge in human islet transplanted mice resulted in an immediate incremental increase of plasma human C-peptide, while the plasma mouse C-peptide was undetectable. Treatments with GLP-1, exenatide, glyburide, nateglinide and sitagliptin effectively increased plasma human C-peptide levels and improved postprandial glucose concentrations. GPR40 agonists also stimulated human C-peptide secretion and significantly improved postprandial glucose in the human islet transplanted mice.
Undergraduate biochemistry students should have great familiarity with titration curves. These cu... more Undergraduate biochemistry students should have great familiarity with titration curves. These curves allow the prediction of protonation states, charges, and isoelectric points. Here we describe an experiment in which students identify four amino acids based on their titration behavior. Students make solutions of each unknown amino acid and monitor the change in pH upon adding aliquots of a strong base. They identify the amino acids based on the shapes of the curves. They annotate the plots with isoelectric points, pKas, buffering regions and the structures of the amino acids.
To obtain a copy of this paper or presentation: note the name of the conference or event in the R... more To obtain a copy of this paper or presentation: note the name of the conference or event in the Resources Relation field. Other useful information can be found in the Availability, Publisher, Research Organization, Author (affiliation information) fields and/or Document ...
Epithelial cells release cytokines and they probably contribute to chronic inflammation detected ... more Epithelial cells release cytokines and they probably contribute to chronic inflammation detected in bronchial asthma, rhinitis and nasal polyposis. To investigate the effect of cultures on cytokine gene expression to compare epithelial cell cytokine release by both healthy nasal nucosa (HNM) and nasal polyps (NP), and the modulation by dexamethasone and to investigate which cytokines may promote eosinophil survival. Epithelials cells were cultured to confluence, human epithelial cell conditioned media generated with or without dexamethasone, and supernatants measured by ELISA. Cytokine gene expression was investigated by reverse transcription-polymerase chain reaction (RT-PCR). Fresh epithelial cells only expressed mRNA for intesleukin-8 (IL-8) and granulocyte macrophage-colony stimulating factor (GM-CSF) while cultured cells expressed mRNA for IL-1 beta, IL-6, IL-8, tumour necrosis factor-alpha (TNF alpha) and GM-CSF. Epithelial cells from NP significantly (P &lt; 0.05) released more IL-8 (25431 +/- 3163 pg/mL), and GM-CSF (1229 +/- 391 pg/mL) than those from HNM (18604 +/- 1723 pg/mL for IL-8; and 611 +/- 98 pg/mL for GM-CSF). Dexamethasone 10 microM inhibited the release of all cytokines, this effect being similar (40-50%) in both HNM and NP, except for IL-6 which was higher in HNM. Eosinophil survival induced by epithelial cell secretions from both HNM and NP was strongly blocked by GM-CSF antibody while it was partially blocked by antibodies to TNF alpha and IL-8. These findings suggest that although epithelial cell culture procedures may upregulate cytokine gene expression, nasal polyps may represent a more active inflammatory tissue by releasing more cytokines than healthy nasal mucosa this release being inhibited by steroids; and that, in addition to GM-CSF, other cytokines such as TNF alpha and IL-8, may also be involved in the promotion of eosinophil survival.
Eosinophilic infiltration of the respiratory mucosa is considered an inflammatory hallmark of all... more Eosinophilic infiltration of the respiratory mucosa is considered an inflammatory hallmark of allergic rhinitis, bronchial asthma and nasal polyposis. However, the mechanisms involved in this infiltration have not yet been totally elucidated. The objective of this study was to investigate and compare the influence of epithelial cell secretions from both nasal polyps (NP) and normal nasal mucosa (NM) on in vitro eosinophil survival. Epithelial cells were identified by microscopy and immunohistochemistry, cultured to confluence, and human epithelial cell conditioned media (HECM) was generated from cultures. Eosinophils were isolated at high viability and purity (&amp;amp;gt; 90%) from peripheral blood and incubated with HECM. HECM from both NM and NP increased eosinophil survival in a dose-dependent manner, this effect being maximal at a concentration of 25% for NM (73.4% +/- 5.5%, n = 26, P &amp;amp;lt; 0.001) and of 10% for NP (74.5% +/- 8.4%, n = 18, P &amp;amp;lt; 0.001). Incubation of monoclonal antibody to human GM-CSF with HECM, neutralized the induction of eosinophil survival by HECM from both NM and NP. HECM from NP contained higher concentrations of GM-CSF (111 +/- 25.4 pg/ml, n = 17) than HECM from NM (97.1 +/- 15.2 pg/ml, n = 8), without reaching statistical significance. Pre-incubation of dexamethasone with eosinophils also blocked HECM-induced eosinophil survival from both NM (10(-8)-10(-5) M; IC50 = 9.5 nM) and NP (10(-7)-10(-5) M; IC50 = 83 nM). These results suggest that: firstly eosinophil infiltration into the respiratory mucosa during allergic reaction and nasal polyposis may be modulated at least in part by GM-CSF from epithelial cells; and secondly epithelial cells from NP might have a more potent effect on inducing eosinophil infiltration of the respiratory mucosa than epithelial cells from NM. Finally, we may consider this as a reliable in vitro model to compare the role of epithelial cells from inflammatory (NP) and non-inflammatory (NM) tissue in respiratory inflammation.
El Estudio caracteriza y actualiza la fauna silvestre vertebrada de la Península de<br> Cos... more El Estudio caracteriza y actualiza la fauna silvestre vertebrada de la Península de<br> Cosigüina, evaluando los elementos ambientales y sociales en que esta se<br> desarrolla, identificando en el proceso las amenazas a la biodiversidad y opciones<br> de conservación. Analizamos los resultados faunísticos de muchas de las<br> "Evaluación de campo" conocidas para la reserva, incluyendo datos históricos. Esta<br> zona presenta una variedad de hábitats típicos de Pacífico nicaragüense,<br> sobresaliendo una importante cobertura vegetal de bosque seco alrededor del<br> volcán (con su laguna cratérica al fondo), así como una amplia zona marinocostera<br> con pequeños parches de esteros y manglares; que en conjunto abrigan<br> poblaciones faunísticas esenciales para el equilibrio ecológico de la zona y de las<br> poblaciones humanas. En total se registran 305 especies de fauna silvestre<br> vertebrada (no ictiológ...
This is a study of the experiences of Latina garment workers and their mostly white managers. It ... more This is a study of the experiences of Latina garment workers and their mostly white managers. It is a women-centered analysis of the social practices at work and at home. As such, the research departs from the structural accounts of the garment industry which portray Latina garment workers as objects who are part of an economic process that tend to erase their lived experiences. Using field site observations at a denim contracting shop and in-depth interviews with Latina garment workers and their managers, I link their personal account of work to how gender, ethnicity, and immigration status impact work. In Los Angeles, Latinas continue to make-up the majority of garment workers. Through their voices we learn the reasons why they entered in the garment industry, why they stay in this exploitative field, and some of the ways they resist their exploitation. Their voices challenge the old myths that garment work takes little skill to master. These women recount their everyday experienc...
Revista Latinoamericana De Metalurgia Y Materiales, Dec 9, 2013
Three materials were deposited on AISI-SAE 4340 steel using the wire arc thermal spray technique.... more Three materials were deposited on AISI-SAE 4340 steel using the wire arc thermal spray technique. The deposited materials are commercially known as 140MXC (Fe, Nb, Cr, W), 530AS, which is a steel similar to AISI-SAE 1015, and 560AS, which is a steel similar to AISI-SAE 420. With the aim of evaluating the best strategy for increasing the corrosion resistance in the coating-substrate system, the coatings were deposited in three different ways: (1) homogeneous monolayers (single layers) of each material, (2) (Double layer) bilayers composed of a monolayer of 140MXC over a monolayer of either 530AS or 560AS, and (3) simultaneous monolayertype (single layer) coatings achieved by depositing 140MXC + 530AS in the first case and 140MXC + 560AS in the second case. The coatings were characterized by optical microscopy and X-ray diffraction. The corrosion resistance was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization. The resistance to polarization of the material deposited in bilayers was increased through the congestion of defects with corrosion products, while the simultaneous monolayers achieved increased corrosion resistance by the reduction of defects with respect to 140MXC. The details and mechanisms of corrosion in the fabricated coatings are described in this study.
Síntesis y caracterización de polvos de dióxido de estaño dopado con hierro (Sn (1-x) Fe x o 2) p... more Síntesis y caracterización de polvos de dióxido de estaño dopado con hierro (Sn (1-x) Fe x o 2) para la preparación de películas delgadas Synthesis and characterization of powders of tin dioxide doped with iron (Sn (1-x) Fe x o 2) for the preparation of thin films López, E. I ; Marín, J. I y Osorio, J. II Resumen. En este trabajo se establecen las condiciones apropiadas para la síntesis de polvos SnO 2 dopado con hierro al 10% a través de la ruta sol-gel. La caracterización de los polvos obtenidos por este método se realiza mediante la aplicación de diferentes técnicas espectroscópicas como Mössbauer e infrarroja por transformada de Fourier, así como por difracción de rayos X.
Cadmium plating on metal surfaces is commonly used for corrosion protection and to achieve good s... more Cadmium plating on metal surfaces is commonly used for corrosion protection and to achieve good solderability on the 304L stainless steel shell of the MC4636 lightning arrestor connector (LAC) for the W76-1 system. This study examined the use of zinc as a potential substitute for the cadmium protective surface finish. Tests were performed with an R and RMA flux and test temperatures of 230ºC, 245ºC, and 260ºC. Contact angle, θ C , served as the generalized solderability metric. The wetting rate and wetting time parameters were also collected. The solderability (θ C) of the Erie Plating Cd/Ni coatings was better than that of similar Amphenol coatings. Although the θ C data indicated that both Cd/Ni platings would provide adequate solderability, the wetting rate and wetting time data showed the Amphenol coatings to have better performance. The Zn/Ni coatings exhibited non-wetting under all flux and temperature conditions. Based on the results of these tests, it has been demonstrated that zinc plating is not a viable alternate to cadmium plating for the LAC connectors 1 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Dept. of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. Contents Pg. Tables iv 1.
Portions of this document may be iiiegible in electronic image products. images are produced from... more Portions of this document may be iiiegible in electronic image products. images are produced from the best avaiiabie originai document. .
1 See Makowski & Ostroy (2001) and Gale (2000) for two essential references on the recent literat... more 1 See Makowski & Ostroy (2001) and Gale (2000) for two essential references on the recent literature about the reestablishment of the perfect competition framework within a strategic behaviour approach as an alternative view regarding the traditional price-taker hypothesis.
Resumo: Con la finalidad de evaluar las propiedades dietéticas de dos fórmulas, una a base de car... more Resumo: Con la finalidad de evaluar las propiedades dietéticas de dos fórmulas, una a base de carne de pollo y la otra ADN (Alimentos Dietético Nutricional elaborado por Laboratorios Davis SA Chile), se reviso 146 expedientes de niños desnutridos severos, ...
The Energy Citations Database (ECD) provides access to historical and current research (1948 to t... more The Energy Citations Database (ECD) provides access to historical and current research (1948 to the present) from the Department of Energy (DOE) and predecessor agencies.
The Energy Citations Database (ECD) provides access to historical and current research (1948 to t... more The Energy Citations Database (ECD) provides access to historical and current research (1948 to the present) from the Department of Energy (DOE) and predecessor agencies.
Objective. To develop a rapid, easy and clinically relevant in vivo model to evaluate novel insul... more Objective. To develop a rapid, easy and clinically relevant in vivo model to evaluate novel insulin secretagogues on human islets, we investigated the effect of insulin secretagogues on functional human islets in a humanized mouse model. Materials/Methods. Human islets were transplanted under the kidney capsule of streptozotocin (STZ)-induced diabetic mice with immunodeficiency. Human islet graft function was monitored by measuring non-fasting blood glucose levels. After diabetes was reversed, human islet transplanted mice were characterized physiologically by oral glucose tolerance and pharmacologically with clinically proven insulin secretagogues, glucagon-like peptide-1 (GLP-1), exenatide, glyburide, nateglinide and sitagliptin. Additionally, G protein-coupled receptor 40 (GPR40) agonists were evaluated in this model. Results. Long-term human islet graft survival could be achieved in immunodeficient mice. Oral glucose challenge in human islet transplanted mice resulted in an immediate incremental increase of plasma human C-peptide, while the plasma mouse C-peptide was undetectable. Treatments with GLP-1, exenatide, glyburide, nateglinide and sitagliptin effectively increased plasma human C-peptide levels and improved postprandial glucose concentrations. GPR40 agonists also stimulated human C-peptide secretion and significantly improved postprandial glucose in the human islet transplanted mice.
Undergraduate biochemistry students should have great familiarity with titration curves. These cu... more Undergraduate biochemistry students should have great familiarity with titration curves. These curves allow the prediction of protonation states, charges, and isoelectric points. Here we describe an experiment in which students identify four amino acids based on their titration behavior. Students make solutions of each unknown amino acid and monitor the change in pH upon adding aliquots of a strong base. They identify the amino acids based on the shapes of the curves. They annotate the plots with isoelectric points, pKas, buffering regions and the structures of the amino acids.
To obtain a copy of this paper or presentation: note the name of the conference or event in the R... more To obtain a copy of this paper or presentation: note the name of the conference or event in the Resources Relation field. Other useful information can be found in the Availability, Publisher, Research Organization, Author (affiliation information) fields and/or Document ...
Epithelial cells release cytokines and they probably contribute to chronic inflammation detected ... more Epithelial cells release cytokines and they probably contribute to chronic inflammation detected in bronchial asthma, rhinitis and nasal polyposis. To investigate the effect of cultures on cytokine gene expression to compare epithelial cell cytokine release by both healthy nasal nucosa (HNM) and nasal polyps (NP), and the modulation by dexamethasone and to investigate which cytokines may promote eosinophil survival. Epithelials cells were cultured to confluence, human epithelial cell conditioned media generated with or without dexamethasone, and supernatants measured by ELISA. Cytokine gene expression was investigated by reverse transcription-polymerase chain reaction (RT-PCR). Fresh epithelial cells only expressed mRNA for intesleukin-8 (IL-8) and granulocyte macrophage-colony stimulating factor (GM-CSF) while cultured cells expressed mRNA for IL-1 beta, IL-6, IL-8, tumour necrosis factor-alpha (TNF alpha) and GM-CSF. Epithelial cells from NP significantly (P &lt; 0.05) released more IL-8 (25431 +/- 3163 pg/mL), and GM-CSF (1229 +/- 391 pg/mL) than those from HNM (18604 +/- 1723 pg/mL for IL-8; and 611 +/- 98 pg/mL for GM-CSF). Dexamethasone 10 microM inhibited the release of all cytokines, this effect being similar (40-50%) in both HNM and NP, except for IL-6 which was higher in HNM. Eosinophil survival induced by epithelial cell secretions from both HNM and NP was strongly blocked by GM-CSF antibody while it was partially blocked by antibodies to TNF alpha and IL-8. These findings suggest that although epithelial cell culture procedures may upregulate cytokine gene expression, nasal polyps may represent a more active inflammatory tissue by releasing more cytokines than healthy nasal mucosa this release being inhibited by steroids; and that, in addition to GM-CSF, other cytokines such as TNF alpha and IL-8, may also be involved in the promotion of eosinophil survival.
Eosinophilic infiltration of the respiratory mucosa is considered an inflammatory hallmark of all... more Eosinophilic infiltration of the respiratory mucosa is considered an inflammatory hallmark of allergic rhinitis, bronchial asthma and nasal polyposis. However, the mechanisms involved in this infiltration have not yet been totally elucidated. The objective of this study was to investigate and compare the influence of epithelial cell secretions from both nasal polyps (NP) and normal nasal mucosa (NM) on in vitro eosinophil survival. Epithelial cells were identified by microscopy and immunohistochemistry, cultured to confluence, and human epithelial cell conditioned media (HECM) was generated from cultures. Eosinophils were isolated at high viability and purity (&amp;amp;gt; 90%) from peripheral blood and incubated with HECM. HECM from both NM and NP increased eosinophil survival in a dose-dependent manner, this effect being maximal at a concentration of 25% for NM (73.4% +/- 5.5%, n = 26, P &amp;amp;lt; 0.001) and of 10% for NP (74.5% +/- 8.4%, n = 18, P &amp;amp;lt; 0.001). Incubation of monoclonal antibody to human GM-CSF with HECM, neutralized the induction of eosinophil survival by HECM from both NM and NP. HECM from NP contained higher concentrations of GM-CSF (111 +/- 25.4 pg/ml, n = 17) than HECM from NM (97.1 +/- 15.2 pg/ml, n = 8), without reaching statistical significance. Pre-incubation of dexamethasone with eosinophils also blocked HECM-induced eosinophil survival from both NM (10(-8)-10(-5) M; IC50 = 9.5 nM) and NP (10(-7)-10(-5) M; IC50 = 83 nM). These results suggest that: firstly eosinophil infiltration into the respiratory mucosa during allergic reaction and nasal polyposis may be modulated at least in part by GM-CSF from epithelial cells; and secondly epithelial cells from NP might have a more potent effect on inducing eosinophil infiltration of the respiratory mucosa than epithelial cells from NM. Finally, we may consider this as a reliable in vitro model to compare the role of epithelial cells from inflammatory (NP) and non-inflammatory (NM) tissue in respiratory inflammation.
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