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Sample records for ddq bajo tensiones

  1. Spring back evaluation by bending under tension tests in conditions of multiaxial stresses corresponding to deep drawing processes. Application to AISI 304 DDQ stainless steel sheet; Evaluacion del springback mediante ensayos de doblado bajo tension en condiciones de multiaxialidad tipicas de los procesos de embuticion profunda. Aplicacion a chapa de acero inoxidable AISI 304 DDQ

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, V.; Coello, J.; Martinez, A.; Calatayud, A.

    2013-09-01

    In this paper, a methodology has been developed for evaluating the spring back of AISI 304 DDQ stainless steel sheet based on a bending under tension test. The main difference of the methodology herein carried out is that tests are made under the multiaxial stresses state that take place in deep drawing processes. This affects to the level of stress value in the test and to the hardening state of the sheet. Springback evaluation has been done in two different areas. Bending area has been evaluated from elastic recovery ratio defined as the ratio between the bending radius after and before bending. Bending and unbending extreme has been studied from the measured curvature radius in this area and taking into account the geometric equivalence of the test with the drawing cups process. Results found allow to state that drawing ratio or deformation ratio have a negligible influence on the springback into the range of values experimented here. Bending radius has hardly influence as well while bending angle is the most significant variable. The results obtained are compared to those measured in deep-drawn cups, finding a great agreement. (Author)

  2. Distribución de tensiones tangenciales en vigas de sección constante bajo esfuerzos cortantes

    OpenAIRE

    Fernández, T.; Viaño, J.; Samartín, A.

    2000-01-01

    En este trabajo se analizan algunos resultados obtenidos por Trabucho y Viaño, mediante desarrollos asintótico de las ecuaciones de la elasticidad tridimensional en vigas de sección constante, para la distribución de tensiones tangenciales en una sección transversal bajo la acción de un esfuerzo cortante. Se aplican, con carácter ilustrativo, a vigas con distintos tipos de secciones transversales (rectangular, circular, triangular y perfil UPN) comparando los resultados con los qu...

  3. Evaluación de la fuerza de doblado y de fricción en el conformado de chapa de acero inoxidable AISI 304 DDQ mediante ensayos de doblado en condiciones multiaxiales de embutición

    Directory of Open Access Journals (Sweden)

    Coello, J.

    2012-08-01

    Full Text Available Die radius is a critical area from the viewpoint of friction in forming processes. Moreover the sheet, that has been previously deformed in flange area, suffers bending and unbending stresses. Then, die-sheet contact in die radius must be especially considered in order to guarantee the suitable lubrication conditions. In the present work, a test method is carried out for evaluating an AISI 304 DDQ steel under similar conditions to those existing in the die radius area and that, usually, are not really reproduced in traditional bending under tensions tests. Deformation under pure shear condition, the bending and the radius angle have been established as variables of the tests. Results allow to obtain the apparent pressure sheet-bending tool, that increases with bending angle and decreases with tool radius. This last variable is the most significant while the bending angle has lesser influence. Although experimental results present some concordances with values obtained by analytical methods, some corrections must be considered in them in order to improve the theoretical values.

    El radio de entrada a la matriz se considera una de las zonas críticas en los procesos de conformado de chapa mediante embutición profunda. El análisis de la fuerza de fricción y de doblado existentes resulta importante para predecir el comportamiento de la chapa en dicha zona, así como para garantizar una lubricación adecuada a las condiciones de procesado. En el presente trabajo, se aplica un método de ensayo que evalúa las acciones en el proceso de doblado del acero AISI 304 DDQ bajo condiciones similares a las que sufre el material en los procesos de embutición y que no son reproducidas por los clásicos ensayos de doblado bajo tensión. Se establecen como variables la deformación experimentada previamente por el material en condiciones típicas de cortante puro, “pure shear”, el ángulo de doblado y el radio de doblado. Los resultados obtenidos

  4. Spectrophotometric and electrochemical studies of the interaction of cryptand 222 with DDQ and I2 in ethanol solution

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    Abolfazl Semnani

    2006-12-01

    Full Text Available Spectrophotometric and electrochemical studies concerning the interaction of cryptand 222 with DDQ and I2 have been performed in ethanol solution. In the case of DDQ, the results are indicative of the formation of C222¬+ and DDQ- through an equilibrium reaction. The results of I2 indicate the formation of I2-ethanol complex and I3- in the absence of C222. In the presence of C222, the formation of C222I¬+ and I3- through a non-equilibrium reaction is confirmed. The equilibrium constant of the redox reaction between DDQ and C222 has been calculated from the absorbance mole ratio data, using the nonlinear least square program “KINFIT”. The electrochemical reversibility of I-/I2 couple and irreversibility of DDQ/DDQ- is indicated by amperometry. The behavior of DDQ and I2 has been compared. A comparison with aprotic solvents has also been made.

  5. Análisis de tensiones en árboles de geometría compleja bajo cargas debido al efecto giroscópico.

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    M. Sánchez Noa

    2005-09-01

    Full Text Available En el presente trabajo se exponen los resultados del análisis realizado en árboles de compleja geometríapertenecientes a un multiplicador planetario tipo 2KH-A destinado a emplearse en aerogeneradores deelectricidad. En el mismo, se presentan los modelos físico-matemáticos de dichos árboles para seranalizados mediante el método de los elementos finitos, considerando el estado de carga que surge alfuncionar el mecanismo y contemplando el efecto adicional de las cargas giroscópicas. Se muestran laszonas de conflicto de tensiones y se analizan propuestas de diseño que permitan, garantizando laresistencia y rigidez, realizar variaciones dimensionales y mejorar la compacidad de los elementos,disminuyendo a la vez el peso de los mismos.

  6. Elevated voltage level I.sub.DDQ failure testing of integrated circuits

    Science.gov (United States)

    Righter, Alan W.

    1996-01-01

    Burn in testing of static CMOS IC's is eliminated by I.sub.DDQ testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip.

  7. Elevated voltage level I{sub DDQ} failure testing of integrated circuits

    Science.gov (United States)

    Righter, A.W.

    1996-05-21

    Burn in testing of static CMOS IC`s is eliminated by I{sub DDQ} testing at elevated voltage levels. These voltage levels are at least 25% higher than the normal operating voltage for the IC but are below voltage levels that would cause damage to the chip. 4 figs.

  8. Determinación de los indicadores de deformación bajo tensiones multiaxiales de embutición. Aplicación al acero electrocincado DC-05 (UNE en ISO 10130

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    Miguel, V.

    2007-04-01

    Full Text Available In this work a methodology to investigate deep drawing quality steel sheets deformation tendency under multiaxial deep drawing stresses has been proposed. The method consists in assaying a sheet in a wedge die in order to introduce a pure shear estate in the material. 0º, 45º and 90º rolling directions are selected in the assays, and transversal strain is the variable considered in them. A strain coefficient ‰ has been defined in order to evaluate thickness variations in the test. Almost no changes in thickness have been registered and this indicates that strain carried out in the test is similar to that taking place in deep drawing. The stress necessary for practice a certain plastic deformation is obtained too and a potential function between them is formulated. Indicators presented in this work are compared to anisotropy and strength coefficients obtained in normalized tensile tests. These results allow us to justify the steel behaviour in the cup deep drawing processes related to ear forming.

    En este trabajo se establece una metodología para la investigación de la tendencia a la deformación de chapa de acero de alta embutibilidad bajo tensiones multiaxiales de embutición. El método consiste en ensayar chapa en una matriz con forma de cuña produciendo en el material un estado de deformación típico de embutición (pure shear. Se seleccionan tres direcciones de laminación (0º, 45º y 90º y se establece la deformación en anchura como variable de ensayo. Se ha definido un coeficiente de deformación con el fin de evaluar las variaciones obtenidas en el espesor del material constatándose la no existencia de cambios significativos en éste. También, se obtiene la tensión necesaria para realizar distintas deformaciones estableciendo correlaciones de tipo potencial tensión-deformación. Se contrastan los indicadores obtenidos con el índice de anisotropía y el de endurecimiento del material bajo condiciones normalizadas

  9. Influencia del medio de ensayo y dirección de aplicación de la carga en el comportamiento a corrosión bajo tensiones de la aleación de aluminio 7075

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    Badía, J. M.

    2004-12-01

    Full Text Available The goal of this work is to prove the validity of using synthetic sea water as an alternative method instead of the NaCl solution used in stress corrosion crack growth tests in aluminium alloys, according to ASTM G 44. Several samples of 7075 alloy have been tested in different conditions and directions in both environments, which can be considered as equivalent. Only the samples tested in thickness direction have shown crack growth during the test. The use of sea water entails a great advantage in practice, by less superficial alteration, and lets therefore a much more reliable measure of the crack.

    El objetivo de este trabajo es comprobar la validez del empleo de agua de mar sintética como método alternativo a la solución de NaCl utilizada en los ensayos de crecimiento de grieta por corrosión bajo tensiones en aleaciones de aluminio, según la norma ASTM G- 44. Para ello, se ha procedido al ensayo de muestras de aleación 7075 en diferentes estados de tratamiento y con distintas orientaciones en ambos medios, comprobándose que pueden considerarse equivalentes. Sólo las probetas ensayadas en la dirección del espesor mostraron crecimiento de grieta durante los ensayos. La utilización del agua de mar representa una gran ventaja práctica ya que altera mucho menos la superficie de las muestras y permite, por tanto, una medida mucho más fiable de la grieta durante el ensayo.

  10. Recent advances with quiescent power supply current (I(sub DDQ)) testing at Sandia using the HP82000

    Science.gov (United States)

    Righter, A. W.; Leong, D. J.; Cox, L. B.

    Last year at the HP82000 Users Group Meeting, Sandia National Laboratories gave a presentation on I(sub DDQ) testing. This year, some advances are presented on this testing including DUT board fixturing, external DC PMU measurement, and automatic IDD-All circuit calibration. Implementation is examined more than theory, with results presented from Sandia tests. After a brief summary I(sub DDQ) theory and testing concepts, how the break (hold state) vector and data formatting present a test vector generation concern for the HP82000 is described. Fixturing of the DUT board for both types of I(sub DDQ) measurement is then discussed, along with how the continuity test and test vector generation must be taken into account. Results of a test including continuity, IDD-All and I(sub DDQ) Value measurements is shown. Next, measurement of low current using an external PMU is discussed, including noise considerations, implementation and some test results showing nA-range measurements. A method is presented for automatic calibration of the IDD-All analog comparator circuit using RM BASIC on the HP82000, with implementation and measurement results. Finally, future directions for research in this area is explored.

  11. Friction and bending forces evaluation of AISI 304 DDQ steel sheet forming by bending tests under deep-drawing multiaxial stresses; Evaluacion de la fuerza de doblado y de friccion en el conformado de chapa de acero inoxidable AISI 304 DDQ mediante ensayos de doblado en condiciones multiaxiales de embuticion

    Energy Technology Data Exchange (ETDEWEB)

    Coello, J.; Miguel, V.; Ferrer, C.; Calatayud, A.; Martinez, A.

    2012-11-01

    Die radius is a critical area from the viewpoint of friction in forming processes. Moreover the sheet, that has been previously deformed in flange area, suffers bending and unbending stresses. Then, die-sheet contact in die radius must be especially considered in order to guarantee the suitable lubrication conditions. In the present work, a test method is carried out for evaluating an AISI 304 DDQ steel under similar conditions to those existing in the die radius area and that, usually, are not really reproduced in traditional bending under tensions tests. Deformation under pure shear condition, the bending and the radius angle have been established as variables of the tests. Results allow to obtain the apparent pressure sheet-bending tool, that increases with bending angle and decreases with tool radius. This last variable is the most significant while the bending angle has lesser influence. Although experimental results present some concordances with values obtained by analytical methods, some corrections must be considered in them in order to improve the theoretical values. (Author) 18 refs.

  12. Tension Headache

    Science.gov (United States)

    ... tight band around your head. A tension headache (tension-type headache) is the most common type of headache, and ... Headache after a head injury, especially if the headache gets worse ... tension or stress. But research suggests muscle contraction isn't the ...

  13. Túnel bajo el agua

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    Stamhuis, E.

    1964-03-01

    Full Text Available This article describes the results obtained by the Dutch Central Institute of Scientific Research when studying the problem of underwater tunnels. This Institute has sought to establish general specifications for the design of this type of tunnels, so that they shall be more efficient than those at present in use. Firstly, a study was made of the strength, waterproof qualities, and most rational type of ventilation, with a view to drawing up of general principles on this aspect of the design. An analysis is given of the shape, suitable cross sections and constructive methods, and these are compared with those adopted in the construction of underwater tunnels at present in use in America. Particular attention has been given to designs which are largely based on prefabrication and the use of factory made structural parts, and also on the transport and erection of these at the site. The author goes on to discuss the interplay of soil and water pressures, buoyancy forces, and cases in which the tunnel is subjected to important bending and shear forces on particular sections of it. In this connection care is taken to give the theoretical considerations a ready practical interpretation. In particular, a description is given of special distance pieces which connect the two tubes making up a tunnel, also the system of joining two sections of the tube, and the measure of watertightness and flexibility which such joints provide. Finally, a summary is given of the theoretical foundations, as well as a number of observations and items of advise, which are applicable to these types of structures.El ingeniero A. Eggink describió, en un trabajo publicado últimamente, un nuevo tipo de túnel bajo el agua para canalizar la circulación rodada. En este trabajo se desarrolla un análisis sobre las consideraciones que han jugado un papel predominante en la redacción del proyecto de ejecución de un túnel subacuo. Acompañan al trabajo los resultados referentes

  14. Tension headache.

    Science.gov (United States)

    Ziegler, D K

    1978-05-01

    Headache is an extremely common symptom, and many headaches undoubtedly have a relationship to stressful situations. The clear definition, however, of a "tension headache" complex and its differentiation from migraine in some patients is difficult. The problems are in the identification of a specific headache pattern induced by stress or "tension" and the relationship of the symptom to involuntary contraction of neck and scalp muscles. Treatment consists of analgesics and occasionally mild tranquilizers. Psychotherapy consists of reassurance and often other supportive measures, including modification of life styles. Various feedback techniques have been reported of value, but their superiority to suggestion and hypnosis is still problematic.

  15. Viviendas de muy bajo coste

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    Lemus, V.

    1982-11-01

    Full Text Available Not available.En el Instituto de Investigaciones en Materiales de la Universidad Nacional Autónoma de México, se está desarrollando un área de investigación sobre tecnología de materiales y tecnología de sistemas constructivos, la cual está integrada por diversos proyectos encaminados a solucionar problemas relativos a la vivienda. El presente trabajo consiste en el desarrollo de materiales compuestos a base de desechos agrícolas e industriales, con características tales como baja densidad, resistencia adecuada, excelentes propiedades térmicas y acústicas y, fundamentalmente, bajo costo y gran disponibilidad. Los resultados obtenidos son bastante alentadores debido a la durabilidad y resistencia mecánica obtenidos a base del tratamiento proporcionado a la materia orgánica. Se comentan las aplicaciones actuales y futuras de estos nuevos materiales.

  16. A simple spectrophotometric determination of diclofenac sodium in commercial dosage forms using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)

    International Nuclear Information System (INIS)

    Raza, A.; Ansari, T.M.; Niazi, S.B.; Bukhari, S.I.H.

    2005-01-01

    A rapid, simple and sensitive spectrophotometric method has been developed for the determination of diclofenac sodium in pure and tablet formulations. The method depends on the charge-transfer complexation between diclofenac sodium as n-electron donor with 2,3-dichloro-,6-dicyano-1,4-benzoquinone (DDQ) in acetonitrile medium as pi-acceptor to give a colored complex which absorbs maximally at 545 nm. Beer's law has been obeyed in the concentration range of 13-275 micro gram ml/sup -1/ with molar absorptivity of 2.5 x 10/sup 3/L mole/sup -1/cm/sup -1/. The proposed method is precise, accurate and specific for routine quantitative analysis of the drug in bulk and dosage forms. (author)

  17. con bajo peso al nacer

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    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  18. The intangible legacy of the Indonesian Bajo

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    Chandra Nuraini

    2016-05-01

    Full Text Available The Sama-Bajau, or Bajo diaspora, extends from the southern Philippines and Sabah (Malaysian Borneo to the eastern part of Indonesia. The Indonesian Bajo, now scattered along the coasts of Sulawesi (Celebes and East Kalimantan, the Eastern Lesser Sunda Islands and Maluku, were once mostly nomadic fishermen of the sea or ocean freight carriers. Today, the Bajo are almost all fishermen and settled. Their former and present ways of life made them favour intangible forms of culture: it is impossible to transport bulky artefacts when moving frequently by boat, or when living in stilt houses, very close to the sea or on a reef. It is therefore an intangible legacy that is the essence of the Bajo’s culture. Sandro healers have a vast range of expertise that allows them to protect and heal people when they suffer from natural or supernatural diseases. On the other hand, music and especially oral literature are very rich. In addition to song and the pantun poetry contests, the most prestigious genre is the iko-iko, long epic songs that the Bajo consider to be historical rather than fictional narratives. The Bajo’s intangible heritage is fragile, since it is based on oral transmission. In this article, I give a description of this heritage, dividing it into two areas: the knowledge that allows them to “protect and heal” on the one hand, and to “distract and relax”, on the other.

  19. Reactor vessel stud tensioner

    International Nuclear Information System (INIS)

    Malandra, L.J.; Beer, R.W.; Salton, R.B.; Spiegelman, S.R.; Cognevich, M.L.

    1982-01-01

    A quick-acting stud tensioner, for facilitating the loosening or tightening of a stud nut on a reactor vessel stud, has gripper jaws which when the tensioner is lowered into engagement with the upper end of the stud are moved inwards to grip the upper end and which when the tensioner is lifted move outward to release the upper end. (author)

  20. Tension type headache

    Directory of Open Access Journals (Sweden)

    Debashish Chowdhury

    2012-01-01

    Full Text Available Tension type headaches are common in clinical practice. Earlier known by various names, the diagnosis has had psychological connotations. Recent evidence has helped clarify the neurobiological basis and the disorder is increasingly considered more in the preview of neurologists. The classification, clinical features, differential diagnosis and treatment of tension type headache are discussed in this paper.

  1. Tensions in Distributed Leadership

    Science.gov (United States)

    Ho, Jeanne; Ng, David

    2017-01-01

    Purpose: This article proposes the utility of using activity theory as an analytical lens to examine the theoretical construct of distributed leadership, specifically to illuminate tensions encountered by leaders and how they resolved these tensions. Research Method: The study adopted the naturalistic inquiry approach of a case study of an…

  2. Parachute Cord Tension Sensor

    Data.gov (United States)

    National Aeronautics and Space Administration — To design and fabricate a light weight (few oz), very small (~2 inch length) parachute cord tension sensor demonstrator device.A major challenge for the CPAS (The...

  3. Leadership. Using Creative Tension.

    Science.gov (United States)

    Cook, David L.

    1986-01-01

    Leadership involves maintaining a balance of the variables which comprise leadership. Love and fear, types of power, success and effectiveness, and driving and restraining forces are discussed as sources of the creative tension a leader uses to influence others. (MT)

  4. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide.......To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  5. Spontaneous tension haemopneumothorax

    OpenAIRE

    Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

    2008-01-01

    Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such c...

  6. cultivadas bajo un gradiente de sombra

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    Marco V. Gutiérrez

    2007-01-01

    Full Text Available Se evaluó el crecimiento de 9 especies de palmas cultivadas bajo un gradiente de sombra producido por mallas de polipropileno negro de 40, 50, 60, 70 y 80% de sombra, más un tratamiento de malla aluminizada de 70%, y uno con plantas a pleno sol. Las especies evaluadas fueron Caryota mitis (cola de pez, Chamaedorea costaricana (pacaya, Chamaedorea tepejilote (tepejilote, Dypsis lutescens (areca, Licuala elegans (licuala, Phoenix roebelenii (fénix, Ptychosperma macarthurii (palma macarthur, Roystonea regia (palma real, y Veitchia merrillii (navideña. Se midió la altura de las plantas, la longitud de las hojas maduras, y el número de hojas cosechadas, durante 5 cosechas por 2 años. En general, la altura de las plantas y la longitud de las hojas fueron menores a 0-40% de sombra, se incrementaron a 50-70%, y decrecieron a 80%. C. mitis, C. tepejilote, L. elegans y P. macarthurii, se comportaron como especies obligadas de sombra y no sobrevivieron a pleno sol. C. costaricana y D. lutescens sobrevivieron a plena exposición solar, y su crecimiento alcanzó valores máximos a 50-60%. P. roebelenii, R. regia, y V. merrillii mostraron un crecimiento reducido a 0-40%, pero éste mejoró bajo los demás niveles de sombra a lo largo del gradiente. En general, 1-2 años es un periodo apropiado para el cultivo de palmas de crecimiento rápido (R. regia, Chamedorea spp., D. lutescens en casas de mallas. Palmas de lento crecimiento (L.elegans pueden permanecer 3-5 años en una casa de sombra. Se discute estrategias para el uso de gradientes de sombra en el tiempo y en el espacio, según la utilidad y los requerimientos de las especies, los requisitos establecidos por el mercado, y el ciclo de producción del material vegetal.

  7. Determination and analysis of the dispersive optical constants of the 5,5',6,6'-tetraphenyl-2,2'-bi([1,3]dithiolo[4,5-b][1,4]dithiinylidene)-DDQ complex thin film

    International Nuclear Information System (INIS)

    Atalay, Y.; Basoglu, A.; Avci, D.; Arslan, M.; Ozturk, T.; Ertas, E.

    2008-01-01

    The synthesis and optical properties of the 5,5',6,6'-tetraphenyl-2,2'-bi([1,3]dithiolo [4,5-b] [1,4]dithiinylidene)-2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) complex thin film were investigated by the optical characterization. The optical constants such as refractive index, extinction coefficient and absorption coefficient were determined using the transmittance T(λ) and reflectance R(λ) spectra and the refractive index dispersion was analyzed using single oscillator of Wemple-Didomenico model. The single oscillator energy E 0 and the dispersion energy E d were calculated. The effect of temperature on refractive dispersion and optical band gap E g is also discussed. As a result, the annealing temperatures have an important effect on refractive index of thin film

  8. Viviendas de bajo costo sistema SALVY

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    Suárez Ibarra, Salvador

    1984-06-01

    Full Text Available The aim of this work is to offer an alternative for solving the current problem of housing, through a building system which has been developed and tested in our country — the SAL VY SYSTEM. It is directed towards solving the problem of low-cost housing with own technology, enabling these houses to be built quickly, using materials which are not traditional in building, but are abundant in our country. The house presented by us allows the user to extend its height according to his needs and financial possibilities, keeping the free area of the plot for so-called kitchen gardens.Este trabajo tiene como objetivo presentar una alternativa para la solución del problema actual de la vivienda, a través de un sistema constructivo desarrollado y experimentado en nuestro país —SISTEMA SALVY, dirigido a solucionar el problema de la vivienda de bajo costo, con una tecnología propia que permite la construcción de estas viviendas de una manera rápida, utilizando materiales no tradicionales en construcción, pero abundantes en nuestro país. La vivienda que presentamos permite al usuario ampliarla en altura, de acuerdo a sus necesidades y posibilidades económicas, manteniendo el área libre de la parcela para los denominados huertos del hogar.

  9. Spontaneous tension haemopneumothorax.

    Science.gov (United States)

    Patterson, Benjamin Oliver; Itam, Sarah; Probst, Fey

    2008-10-31

    We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported.Aetiology and current approach to spontaneous haemothorax are discussed briefly.

  10. Spontaneous tension haemopneumothorax

    Directory of Open Access Journals (Sweden)

    Itam Sarah

    2008-10-01

    Full Text Available Abstract We present a patient with sudden onset progressive shortness of breath and no history of trauma, who rapidly became haemodynamically compromised with a pneumothorax and pleural effusion seen on chest radiograph. He was treated for spontaneous tension pneumothorax but this was soon revealed to be a tension haemopneumothorax. He underwent urgent thoracotomy after persistent bleeding to explore an apical vascular abnormality seen on CT scanning. To our knowledge this is the first such case reported. Aetiology and current approach to spontaneous haemothorax are discussed briefly.

  11. Restos de vida en Bajo este sol tremendo de Carlos Busqued

    Directory of Open Access Journals (Sweden)

    Marcos Seifert

    2017-07-01

    Full Text Available Este trabajo se propone analizar cómo la novela de Carlos Busqued Bajo este sol tremendo (2009 se apoya en la representación de vidas desechadas, basura y todo tipo de restos para instalarse en una tensión entre orden y exceso. La narración plantea una lógica en la que la basura, en lugar de constituirse en un indicio que posibilite la reconstrucción del paisaje social, exhibe lo desbordante, lo inasimilable y los vacíos de sentido. En el mundo que nos presenta Busqued lo viviente se vuelve resto en la medida en que encarna una heterogeneidad irreductible a cualquier estructura social y productiva. This paper analyzes the way in which Carlos Busqued's novel Bajo este sol tremendo (2009 is based on the representation of discarded lives, garbage, and all kinds of remains and thus proposes a tension between order and excess. The narration raises a logic in which garbage, instead of constituting an indicator that allows for the reconstruction of the social landscape, exhibits the overflowing, the unassimilable, and the voids of meaning. In the world that Busqued presents, the living becomes a remainder because it embodies an irreducible heterogeneity with regards to any social and productive structure.

  12. Túnel bajo el Elba - Hamburgo - Alemania Federal

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1976-03-01

    Full Text Available This important work, constructed to solve the traffic problem between the northern and Southern parts of Hamburg, has an overall length of 3,325 m. The greater part of the tunnel is provided with special aeration, supplied by three ventilation stations. The tunnel is made up of three independent! circulation tubes, each with two traffic lanes. The lateral tubes are intended for one way traffic, whereas the middle lane is designed for two way traffic. In the section under the river itself, these three tubes, along with the ventilating ducts, come together into one single rectangular piece. This particular stretch consists of eight members, which were constructed in nearby dry dock and were later sunk and laid on the river bottom, along a previously excavated trench. It was completed by means of highly advanced technological methods for sealing the joints and subsequently the trench was again covered up with the excavation material. The section under the greatest slope of the river bed was excavated by means of the method of the advancing driller pipe shield, and the end sections were so near the surface that the work was carried out in the open air. The northern ventilation station —a reinforced concrete construction, connecting sections of the tunnel— further contains the safety and control stations for the entire length of the tunnel, and is equipped with the most modern technical devices.Esta importante obra, construida para solucionar el problema del tráfico entre las zonas norte y sur de la ciudad de Hamburgo, tiene una longitud total de 3.325 m. En la mayor parte de su recorrido se utiliza un sistema de aireación especial, abastecido por tres estaciones de ventilación. El túnel está constituido por tres tubos de circulación independientes, con dos carriles cada uno. Los tubos laterales se utilizan para el tráfico en un solo sentido, mientras que el central permite la circulación en ambas direcciones. En el tramo bajo

  13. Creating Tension in Writing.

    Science.gov (United States)

    Folta, Bernarr

    This paper discusses the rationale and teaching methods for a six-week unit, for a high school freshman English Class, on perception, semantics, and writing, which places special focus on developing tension in student writing. The first four objectives of the course focus on perception and the next two focus on semantics. The seventh…

  14. Tension-filled Governance?

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    on the statesituated tension-filled functional relationship between legitimation and accumulation, the study both historically and theoretically reworks this approach and reapplies it for the post-1970s/1990s governance period. It asks whether and to what extent governance has served as a distinctive post- 1970s/1990s...

  15. Rein tension during canter

    NARCIS (Netherlands)

    Egenvall, Agneta; Eisersiö, Marie; Rhodin, Marie; van Weeren, P.R.; Roepstorff, Lars

    2015-01-01

    Riders generally use reins as a means for communication with the horse. At present, the signalling pattern is poorly understood. The aim of this study was to illustrate and analyse the rein tension patterns in a number of rider/horse combinations across a variety of exercises in the canter gait. Our

  16. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta...

  17. Coulomb string tension, asymptotic string tension, and the gluon chain

    OpenAIRE

    Greensite, Jeff; Szczepaniak, Adam P.

    2014-01-01

    We compute, via numerical simulations, the non-perturbative Coulomb potential of pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.

  18. Factores asociados al bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Georgina J Peraza Roque

    2001-10-01

    Full Text Available El bajo peso al nacer (BPN ha constituido un enigma en la ciencia a través de los tiempos. Múltiples son las investigaciones realizadas acerca de las causas que lo producen y las consecuencias que provoca. Su importancia no solo radica en lo que significa en la morbilidad y la mortalidad infantil, sino que estos niños tienen habitualmente múltiples problemas posteriores. El Programa para la Reducción del BPN señala que los niños nacidos con un peso inferior a los 2 500 g presentan riesgo de mortalidad 14 veces mayor durante el primer año de vida, en comparación con los niños que nacen con un peso normal a término. Dentro de los factores de riesgo del BPN se han encontrado con mayor frecuencia en estudios realizados por diferentes autores, los siguientes: el embarazo en la adolescencia, la desnutrición en la madre, el hábito de fumar, la hipertensión arterial durante el embarazo, la sepsis cervicovaginal, la anemia y los embarazos gemelares, entre otros. Es innegable la influencia que el BPN tiene sobre las futuras generaciones, por lo que debe constituir la diana de los esfuerzos que el médico y la enfermera deben desarrollar en su prevención, sobre todo en la comunidadLow birth weight has been an enigma for Science through times. A lot of research works have been carried out about its causes and consequences. The importance of LBW not only lies in its meaning for infant mortality and morbidity but also in the many problems that low birth weight children regularly face in the future. The program for the reduction of LBW points out that newborns weighing under 2500g have during his/her first year of life a mortality risk 14 times higher than newborns with a normal weight at term. Among the low birth weight risk factors, a number of studies by various authors have frequently found the following; pregnancy at adolescence; undernourishment in mothers, smoking, blood hypertension during pregnancy, cervix-vaginal sepsis; anemia, twin

  19. Túnel bajo el puerto de Boston

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1963-05-01

    Full Text Available The new tunnel under Boston harbour has been constructed because of the insufficient capacity of a similar, earlier, tunnel to cope with the ever increasing road traffic. This tunnel is 1,550 ms long, and 9.50 ms in external diameter. There are two traffic lanes, each 3.20 ms wide. Inside it is faced with ceramic tiles, has fluorescent lighting, and ventilation is maintained by means of two ducts, one at each entrance, where the necessary compressor and other equipment has been situated. The most interesting feature of this important project is the excavation method adopted for its construction: the tunnel crosses a clay layer, which at certain places is sufficiently fluid to allow a pneumatic shield to be forced through it leaving hardly any debris behind. It will be readily appreciated that this procedure shows an obvious advantage over ordinary methods, in which it is necessary to cut out, and transport to the exterior all the excavated material. The metal sheathing was by the Commercial Shearing and Stamping Co., Youngstown, Ohio.Este nuevo túnel, bajo el puerto de Boston, es una consecuencia de la necesidad imperiosa que se hacía sentir dada la insuficiente capacidad del otro túnel similar antiguo y el aumento continuo del tráfico urbano y por carretera. Tiene 1.550 m de longitud, 9,50 m de diámetro exterior y una calzada con dos bandas de circulación de 3,20 m de anchura cada una. Está revestido ccn baldosa cerámica, iluminado con luz fluorescente, y el aire viciado se ventila y renueva por medio de dos torres de ventilación—una en cada portal—, en las que se han instalado el equipo mecánico adecuado de ventilación y compresores. La parte más interesante de esta importante obra estriba en los procedimientos empleados para llevar a cabo la excavación, pues atraviesa un banco de arcilla que, en ciertos tramos, es suficientemente fluida para permitir dejarse empujar y ceder paso a un escudo neumático que avanza sin apenas

  20. Tension-type headache

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Jensen, Rigmor; Bendtsen, Lars

    2009-01-01

    The substantial societal and individual burdens associated with tension-type headache (TTH) constitute a previously overlooked major public health issue. TTH is prevalent, affecting up to 78% of the general population, and 3% suffer from chronic TTH. Pericranial myofascial nociception probably...... is important for the pathophysiology of episodic TTH, whereas sensitization of central nociceptive pathways seems responsible for the conversion of episodic to chronic TTH. Headache-related disability usually can be reduced by identification of trigger factors combined with nonpharmacologic and pharmacologic...... treatments, but effective treatment modalities are lacking. Benefits can be gained by development of specific and effective treatment strategies....

  1. General definition of gravitational tension

    International Nuclear Information System (INIS)

    Harmark, T.; Obers, N.A.

    2004-01-01

    In this note we give a general definition of the gravitational tension in a given asymptotically translationally-invariant spatial direction of a space-time. The tension is defined via the extrinsic curvature in analogy with the Hawking-Horowitz definition of energy. We show the consistency with the ADM tension formulas for asymptotically-flat space-times, in particular for Kaluza-Klein black hole solutions. Moreover, we apply the general tension formula to near-extremal branes, constituting a check for non-asymptotically flat space-times. (author)

  2. La organización social en los barrios bajos

    Directory of Open Access Journals (Sweden)

    William Foote Whyte

    2010-07-01

    Full Text Available

    Por mucho tiempo, los sociólogos han estudiado los barrios bajos en términos de desorganización social. El interés en los mismos parece provenir de dos fuentes: una urgencia por promover reformas sociales y un esfuerzo para comprender el proceso de urbanización. Observando el quiebre de los controles del grupo primario en la vida de ciudad, algunos sociólogos han considerado analizar la situación resultante en términos del concepto de desorganización social. Los barrios bajos han sido caracterizados por ciertos sociólogos, como áreas de almas perdidas y misiones, áreas donde individuos y familias viven en intimidad forzada con personas a las cuales normalmente rechazan y evitan; áreas donde no se aprecian estándares de decencia o buena conducta excepto los impuestos por una autoridad externa. Según la opinión de otros sociólogos, los barrios bajos son un área de libertad e individualismo. Harvey Zorbaugh dice que la política en el distrito bajo no es como la política en el distrito de clase media. Como no se ajusta a los estándares de la clase media, no es más que un juego. Más aún, la preocupación con el estudio de la desorganización familiar ha conducido a algunos sociólogos a subestimar cualquier grado de organización que se pueda encontrar en los barrios bajos

  3. Tension type headaches: a review

    African Journals Online (AJOL)

    Location of the pain:There is often a typical location for tension- type headaches, as ... Cranial nerve abnormalities, including papilloedema. • Signs of ... peripheral and central mechanisms underlie tension-type ... Physiotherapy has been shown to be an effective management option for .... Acupuncture in primary headache.

  4. MUSCLE TENSION DYSPHONIA

    Directory of Open Access Journals (Sweden)

    Irena Hočevar Boltežar

    2004-07-01

    Full Text Available Background. Muscle tension dysphonia (MTD is the cause of hoarseness in almost one half of the patients with voice disorders. The otorhinolaryngologic examination discovers no evident organic lesions in the larynx at least in the beginning of the voice problems. The reason for the hoarse voice is a disordered and maladjusted activity of the muscles taking part in phonation and/or articulation. In some patients, the irregular function of the larynx results in mucosal lesions on vocal folds. The factors participating in the development of MTD, directly or indirectly influence the quality of laryngeal mucosa, the activity of the phonatory muscles and/or increase of the vocal load. In the diagnostics and treatment of the MTD a phoniatrician, a speech and language therapist and a psychologist closely cooperate with the patient who must take an active role. The treatment is a long-lasting one but resulted in a high percentage of clinical success.Conclusions. Most likely, MTD is not a special disease but only a reflection of any disorder in the complicated system of regulation and realization of phonation. The prognosis of treatment is good when all unfavourable factors participating in development of MTD are eliminated and a proper professional voice- and psychotherapy started.

  5. Factores de riesgo en el bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Guillermo Díaz Alonso

    Full Text Available Se realizó un estudio retrospectivo de tipo caso control en el área del Policlínico Docente "Luis A. Turcios Lima" del municipio 10 de Octubre durante el período de 1990 a 1993, con el objetivo de identificar el comportamiento del bajo peso al nacer, establecer la existencia y la intensidad de esta entidad con los factores de riesgo seleccionados, e identificar el grado de influencia individual de dichos factores. La muestra quedó conformada por 92 recién nacidos de bajo peso y 468 con normopeso. Las variables estudiadas fueron la edad materna, la valoración ponderal, las complicaciones obstétricas, las enfermedades asociadas con la gestación, el hábito de fumar y el período intergenésico. Se aplicó el test chi-cuadrado, el odds- -ratio y el de riesgo atribuible en los nacimientos expuestos y en la población total. Todas las variables estuvieron asociadas significativamente con el bajo peso al nacer, y fueron identificadas como factores de riesgo con influencia marcada: la edad materna de 35 años o más, la amenaza de parto prematuro, la rotura prematura de membranas, la toxemia y la diabetes mellitus; con efecto moderado, el bajo peso materno, un período intergenésico menor de 1 año, la hipertensión arterial, el asma bronquial, el hábito de fumar, la sepsis urinaria, y con influencia ligera, la edad materna inferior a los 20 años.

  6. CULTIVOS BAJO CUBIERTA EN EL SURESTE DE ESPAÑA

    Directory of Open Access Journals (Sweden)

    Encarnación Gil Meseguer

    2011-01-01

    Full Text Available En España, más de 62.000 ha regadas se cultivan en ambiente controlado, bajo determinadas cubiertas. Dos tercios se localizan en Andalucía, y más de la cuarta parte, en el Sureste de la Península Ibérica. En el espacio surestino, delimitado por la coincidencia de las isolíneas climáticas (isoyeta de los 400 mm anuales e isoterma de 16ºC de TMA y la línea de costa mediterránea entre Almería y Alicante, sobresalen una serie de estructuras con cubiertas de plásticos y mallas para la producción de cultivos intensivos en las comarcas del Levante Almeriense-Bajo Almanzora, Lorca y Valle Guadalentín, Campo de Cartagena-Mar Menor, Meridional de Alicante-Vega Baja, etc. Los avances tecnológicos aplicados al riego y al ciclo natural de la planta, se incorporan al cultivo forzado bajo cubierta, logrando modificar el ciclo de cultivo, con una amplitud en los calendarios para presentar el producto en los momentos de mayor demanda. El interés de esta agricultura intensiva de invernaderos, mallas y acolchados radica en su mayor productividad, empleo y precio final del producto.

  7. Tension pneumocephalus: Mount Fuji sign

    Directory of Open Access Journals (Sweden)

    Pulastya Sanyal

    2015-01-01

    Full Text Available A 13-year-old male was operated for a space occupying lesion in the brain. A noncontrast computed tomography scan done in the late postoperative period showed massive subdural air collection causing compression of bilateral frontal lobes with widening of interhemispheric fissure and the frontal lobes acquiring a peak like configuration - causing tension pneumocephalus-"Mount Fuji sign." Tension pneumocephalus occurs when air enters the extradural or intradural spaces in sufficient volume to exert a mass or pressure effect on the brain, leading to brain herniation. Tension pneumocephalus is a surgical emergency, which needs immediate intervention in the form of decompression of the cranial cavity by a burr hole or needle aspiration. The Mount Fuji sign differentiates tension pneumocephalus from pneumocephalus.

  8. Mitochondrial Respiration and Oxygen Tension.

    Science.gov (United States)

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  9. Aulas-laboratorios de bajo costo, usando TIC

    Directory of Open Access Journals (Sweden)

    Silvia E. Calderón

    2015-01-01

    Full Text Available En este trabajo se presentan los resultados de una propuesta educativa orientada a promover el desarrollo de un pensamiento critico y un mayor interes por las ciencias experimentales. Con este fin desarrollamos propuestas de proyectos educativos susceptibles de ser destinadas a las aulas y laboratorios de las escuelas secundarias y primeros anos de la universidad, que resaltan los aspectos metodologicos de las ciencias. Aqui, realizamos una compilacion de varios proyectos, que ilustran formas de incorporar las tecnologias de la informacion y la comunicacion (TIC en diversos experimentos de ciencias, muchos de ellos publicados individualmente anteriormente, y que en conjunto se pueden utilizar para implementar un aula-laboratorio de bajo costo. Con TIC hacemos referencia a la convergencia de computadoras, sistemas audiovisuales, Internet, telefonia, y diversos equipos que se integran con algunos de ellos. Los proyectos intentan integrar areas como fisica, matematica, quimica, informatica, arte, etc. y apuntan a que los estudiantes puedan responder a las preguntas: .Como sabemos esto?, .Por que creemos en aquello? Preguntas que ilustran la naturaleza del pensamiento cientifico. Nuestra contribucion mas significativa es haber desarrollado ≪aulas-laboratorios≫ de muy bajo costo, usando TIC. Con el advenimiento de programas como ≪Una Laptop por Nino≫ que se estan implementando en varios paises de Latinoamerica, resulta oportuno utilizar este recurso como base para generar laboratorios de bajo costo, que creemos pueden ser una herramienta util para mejorar el aprendizaje de las ciencias, incentivar vocaciones y contribuir a desarrollar un pensamiento critico, a la par de desarrollar habilidades con el uso de las TIC que pueden ser de utilidad en diversos ambitos academicos y laborales.

  10. [Epiphytic algae from Bajo Pepito, Isla Mujeres, Quintana Roo, Mexico].

    Science.gov (United States)

    Quan-Young, L I; Díaz-Martín, M A; Espinoza-Avalos, J

    2006-06-01

    A total of 96 epiphytic algae species were identified from Bajo Pepito, Quintana Roo, México. 60.4% (58) belonged to the Rhodophyta, 19.79% (19) to the Phaeophyta, 16.6% (16) to the Chlorophyta and 3.1% (3) to the Cyanophyta; 49 species (50.5%) were found only in one month, while Heterosiphonia crispella was found in all of the sampled months. That species provided the largest contribution to the biomass of epiphytes. During January we registered the greater biommass and richness of epiphytes species, coincidently with high values of host species cover and rainfall.

  11. Desafío con wssv bajo fluctuaciones de temperatura

    OpenAIRE

    Sonnenholzner, Stanislaus

    2002-01-01

    Desafío con WSSV bajo fluctuaciones de temperatura En trabajos anteriores sobre el efecto de la temperatura del agua sobre la supervivencia del camarón infectado con el virus de la Mancha Blanca, se demostró que una temperatura constante de 33ºC por 8 días genera una respuesta inmune en el camarón correlacionada a una supervivencia superior al 90%, lo cual se tradujo posteriormente en una propuesta práctica de cultivo de camarón en estanques con invernaderos, actualmente en evaluación e...

  12. Magnetic tension and gravitational collapse

    International Nuclear Information System (INIS)

    Tsagas, Christos G

    2006-01-01

    The gravitational collapse of a magnetized medium is investigated by studying qualitatively the convergence of a timelike family of non-geodesic worldlines in the presence of a magnetic field. Focusing on the field's tension, we illustrate how the winding of the magnetic forcelines due to the fluid's rotation assists the collapse, while shear-like distortions in the distribution of the field's gradients resist contraction. We also show that the relativistic coupling between magnetism and geometry, together with the tension properties of the field, lead to a magneto-curvature stress that opposes the collapse. This tension stress grows stronger with increasing curvature distortion, which means that it could potentially dominate over the gravitational pull of the matter. If this happens, a converging family of non-geodesic worldlines can be prevented from focusing without violating the standard energy conditions

  13. Bajo materialismo y surrealismo. El debate Bataille-Breton

    Directory of Open Access Journals (Sweden)

    Noelia Denise Dunan

    2015-01-01

    Full Text Available Hacia 1923 Georges Bataille era un joven desconocido que comenzaba a entablar amistades y también enemistades en el núcleo del movimiento surrealista e intelectual de París. Alentado por algunos de aquellos vínculos, lee a Mauss y Durkheim, Nietzsche y Freud y, comienza a delinear un pensamiento que se plasmará en la creación de Documents. Resulta difícil comprender la relevancia de esta revista y la producción batailleana sin referir a sus primeras lecturas y al debate que tempranamente entabló con el máximo exponente del movimiento surrealista, André Breton. Bataille coordinó allí un grupo de disidentes y convirtió la publicación en una máquina contra el surrealismo. El presente artículo desarrolla la formación de Bataille para hacer hincapié en la categoría de bajo materialismo construida en tensión entre el idealismo surrealista y los distintos materialismos. Así puede verse que Documents y el bajo materialismo conjugan las preocupaciones que perseguirá toda su vida.

  14. Perubahan Sosial Pada Komunitas Suku Bajo Di Pesisir Teluk Tomini

    Directory of Open Access Journals (Sweden)

    Muhammad Obie

    2016-06-01

    Full Text Available Abstract: Society and culture of human being always change as an ever –present phenomena in the world. A distinction is sometimes made then between processes of change within the social structure, which serve in part to maintain the structure, and, even the processes itself can be slow or fast through evolusion and revolusion.   One of the factors that quicken the social change process is the government interventions. This study aims at analyzing the social change on the Bajo Tribe community as the impact of various government programs at Tomini bay coastal. This research used strategy of historical sociology. The kinds of data collected were primer and secondary data that were analyzed by using qualitative approac. The result showed that various   government programs at Tomini bay, such as designating conservation area, granting concession license to private sectors through forest concession right (FCR, indefeasible right of use (IRU, and fishing industry at the bay had caused the loss of access of the Bajo tribe community to coastal and marine resources area. Various interventions of government programs had implication on resettlement of the Bajo tribe community, causing the Bajo tribe divided into sea Bajo and land Bajo. The loss of access of the Bajo tribe to coastal and marine resources caused traditional institution weaken which made its philosophy of living in harmony with nature, and  conservation ethics fade away, its local wisdom, and self identity lose, and its social capital destructed.  الملخص: كان المجتمع وحضارته متغيّرين في أيّ كان المجتمع وهذه الحضارة. ويكون الفرق في كون هذا التغيّر. قد تكون عملية التغيّر متمهّلة أو سريعة وقد تكون عن طريق التطوّر والثّورة. وأحد العناصر المسرعة في عملية هذا التغيّر هو تدخّل الحكومة. حاولت هذه

  15. AUTOGENIC THERAPY IN TENSION HEADACHE

    Science.gov (United States)

    Amruthraj, Brunda; Mishra, H.; Kumaraiah, V.

    1987-01-01

    SUMMARY Ten subjects diagnosed as Psychalgia were taken for study. A multiple baseline design was adapted and clients were subjected to 30 sessions of autogenic training. They were assessed using physiological (EMG and thermal change) and behavioural measures (Visual analogue scale and behavioural symptom checklist). Findings revealed autogenic therapy to be effective in reducing tension headache. PMID:21927245

  16. Tensions of Corporate Social Responsibility

    DEFF Research Database (Denmark)

    Strand, Robert

    , and formally rational tools like key performance indicators (KPIs) can be developed and employed in service of the selected substantively rational ends. I show how these KPIs can serve to highlight tensions between substantively rational ends. As such, I argue the CSR bureaucracy can create a space...

  17. AUTOGENIC THERAPY IN TENSION HEADACHE

    OpenAIRE

    Amruthraj, Brunda; Mishra, H.; Kumaraiah, V.

    1987-01-01

    SUMMARY Ten subjects diagnosed as Psychalgia were taken for study. A multiple baseline design was adapted and clients were subjected to 30 sessions of autogenic training. They were assessed using physiological (EMG and thermal change) and behavioural measures (Visual analogue scale and behavioural symptom checklist). Findings revealed autogenic therapy to be effective in reducing tension headache.

  18. bajo el bosque en Costa Rica. 1980-2000

    Directory of Open Access Journals (Sweden)

    Rafael Ocampo

    2007-01-01

    Full Text Available La ipecacuana o raicilla, hierba nativa de América, es la única planta medicinal del trópico húmedo de Costa Rica cultivada bajo el bosque. Es cultivada en la región Huetar Norte, limítrofe con Nicaragua; la raíz seca de ipecacuana se ha comercializado en Costa Rica como materia prima para la industria farmacéutica internacional desde principios del siglo XX. De acuerdo con las estadísticas oficiales, las exportaciones de raicilla desde Costa Rica en los últimos 20 años han significado un promedio de 64 t año-1. Este trabajo resume actividades relacionadas con la descripción y cultivo de la planta, así como algunos de los aspectos agroecológicos de su cultivo.

  19. Factores de riesgo en el bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Guillermo Díaz Alonso

    1995-06-01

    Full Text Available Se realizó un estudio retrospectivo de tipo caso control en el área del Policlínico Docente "Luis A. Turcios Lima" del municipio 10 de Octubre durante el período de 1990 a 1993, con el objetivo de identificar el comportamiento del bajo peso al nacer, establecer la existencia y la intensidad de esta entidad con los factores de riesgo seleccionados, e identificar el grado de influencia individual de dichos factores. La muestra quedó conformada por 92 recién nacidos de bajo peso y 468 con normopeso. Las variables estudiadas fueron la edad materna, la valoración ponderal, las complicaciones obstétricas, las enfermedades asociadas con la gestación, el hábito de fumar y el período intergenésico. Se aplicó el test chi-cuadrado, el odds- -ratio y el de riesgo atribuible en los nacimientos expuestos y en la población total. Todas las variables estuvieron asociadas significativamente con el bajo peso al nacer, y fueron identificadas como factores de riesgo con influencia marcada: la edad materna de 35 años o más, la amenaza de parto prematuro, la rotura prematura de membranas, la toxemia y la diabetes mellitus; con efecto moderado, el bajo peso materno, un período intergenésico menor de 1 año, la hipertensión arterial, el asma bronquial, el hábito de fumar, la sepsis urinaria, y con influencia ligera, la edad materna inferior a los 20 años.A case-control retrospective study was carried out at "Luis A. Turcios Lima" Teaching Polyclinics form 10 de Octubre municipality during the period of 1990-1993, with the aim of identifying the behaviour of low birth weight, establishing the occurrence and intensity of this entity with selected risk factors, and identifying the degree of individual influence of such factors. The sample consisted of 92 low birth weight infants and 468 with normal weight. Variables studied were: maternal age, weight appraisal, and obstetric complications, diseases associated with pregnancy, smoking habit, and the

  20. Urinary incontinence - tension-free vaginal tape

    Science.gov (United States)

    ... ency/article/007377.htm Urinary incontinence - tension-free vaginal tape To use the sharing features on this page, please enable JavaScript. Placement of tension-free vaginal tape is surgery to help control stress urinary ...

  1. Robust Tensioned Kevlar Suspension Design

    Science.gov (United States)

    Young, Joseph B.; Naylor, Bret J.; Holmes, Warren A.

    2012-01-01

    One common but challenging problem in cryogenic engineering is to produce a mount that has excellent thermal isolation but is also rigid. Such mounts can be achieved by suspending the load from a network of fibers or strings held in tension. Kevlar fibers are often used for this purpose owing to their high strength and low thermal conductivity. A suite of compact design elements has been developed to improve the reliability of suspension systems made of Kevlar.

  2. Surface Tension Confines Cryogenic Liquid

    Science.gov (United States)

    Castles, Stephen H.; Schein, Michael E.

    1989-01-01

    New type of Dewar provides passive, constant-temperature cryogenic cooling for scientific instruments under normal-to low-gravity conditions. Known as Surface-Tension-Contained Liquid Cryogen Cooler (STCLCC), keeps liquid cryogen in known location inside the Dewar by trapping liquid inside spongelike material. Unique sponge material fills most of volume of inner tank. Sponge is all-silica, open-cell material similar to that used for Space Shuttle thermal-protection tiles.

  3. Delayed Tension Pneumothorax During Surgery

    Directory of Open Access Journals (Sweden)

    Ying-Lun Chen

    2005-10-01

    Full Text Available Tension pneumothorax is a life-threatening emergency that rapidly results in cardiopulmonary arrest. It requires prompt diagnosis and treatment. We present 2 cases from our practice, 1 caused by blunt chest trauma and the other resulting from laparoscopic surgery. Both were successfully treated by insertion of a chest tube. The diagnosis and treatment of intraoperative pneumothorax is discussed together with a review of the literature.

  4. Factores de riesgo de bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Marcelo Bortman

    1998-05-01

    Full Text Available El bajo peso al nacer (BPN es el principal factor determinante conocido de la mortalidad infantil. Pese a la notable reducción de las tasas de mortalidad infantil y al aumento de las tasas de supervivencia de niños con BPN, en Neuquén, Argentina, no se han observado descensos notables de las tasas de BPN. El propósito de este estudio fue conocer los factores de riesgo de BPN, su frecuencia en la población y el papel de la atención prenatal en su prevención, y desarrollar una escala de riesgo que permita identificar a las mujeres en mayor riesgo de dar a luz un niño de bajo peso. Con tal propósito se realizó un estudio transversal en el cual se utilizó 50% de los datos del Sistema Informático Perinatal correspondientes al período 1988­1995 y procedentes de los 29 hospitales de la provincia de Neuquén (46 171 nacimientos. Se analizaron la distribución del peso y la frecuencia de los posibles factores de riesgo de BPN. La asociación entre estos factores y el BPN se analizó mediante un modelo de regresión logística. Con los resultados obtenidos se desarrolló una escala aditiva, que fue validada con el 50% restante de los registros de nacimientos. La razón de posibilidades (RP más elevada correspondió a la falta de atención prenatal (RP = 8,78; IC95%: 6,7 a 11,4. Las RP asociadas con una atención prenatal inadecuada, una primera consulta prenatal tardía, preeclampsia o eclampsia, hemorragia o anomalías de la placenta o sus membranas e historia de un hijo previo con BPN fueron mayores de 2,0. El riesgo de tener hijos con BPN también fue más alto en las mujeres mayores de 40 años, las menores de 20, las solteras, las fumadoras, aquellas cuyo intervalo intergenésico fue menor de 18 meses y las que tenían un índice de masa corporal menor de 20. Por último, se encontró una relación lineal directa entre el puntaje en la escala y el riesgo de tener un hijo con BPN.

  5. The Plastic Tension Field Method

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2005-01-01

    This paper describes a calculation method for steel plate girders with transverse web stiffeners subjected to shear. It may be used for predicting the failure load or, as a design method, to determine the optimal amount of internal web stiffeners. The new method is called the plastic tension field...... method. The method is based on the theory of plasticity and is analogous to the so-called diagonal compression field method developed for reinforced concrete beams with transverse stirrups, which is adopted in the common European concrete code (Eurocode 2). Many other theories have been developed...

  6. Axelrod's model with surface tension

    Science.gov (United States)

    Pace, Bruno; Prado, Carmen P. C.

    2014-06-01

    In this work we propose a subtle change in Axelrod's model for the dissemination of culture. The mechanism consists of excluding from the set of potentially interacting neighbors those that would never possibly exchange. Although the alteration proposed does not alter the state space topologically, it yields significant qualitative changes, specifically the emergence of surface tension, driving the system in some cases to metastable states. The transient behavior is considerably richer, and cultural regions become stable leading to the formation of different spatiotemporal patterns. A metastable "glassy" phase emerges between the globalized phase and the disordered, multicultural phase.

  7. ¿Aerolíneas de bajo costo en colombia?

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Mantilla

    2003-11-01

    Full Text Available Con la apertura del mercado en Colombia, la competencia entre aerolíneas se agudizó ante la entrada de nuevos operadores y la flexibilización de tarifas como estrategia para la captación de una mayor demanda. Las ventajas competitivas de cada aerolínea fueron el punto clave para la disputa del mercado y todas ellas trabajan hoy en fórmulas que les permitan maximizar beneficios y minimizar costos, enfrentando así la crisis que vive la industria, debido a los acontecimientos del 11 de septiembre de 2001. Puede decirse que los grandes esfuerzos se hacen en los departamentos comerciales, pues debido al auge de las tecnologías y al uso del internet, tanto empresas de transporte aéreo como agentes turísticos deben enfrentar el problema de la competencia de precios. Sin embargo, esto les ofrece a las aerolíneas la oportunidad de comercializar sus servicios a "bajo costo", esquema que ha resultado favorable para empresas y clientes.

  8. Factores de riesgo del bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Ernesto Rosell Juarte

    1996-06-01

    Full Text Available Se realizó una investigación de casos y controles en las mujeres que parieron niños con bajo peso, de los consultorios urbanos de médicos de la familia pertenecientes al Policlínico Comunitario Docente "Carlos J. Finlay" de Camagüey, durante el año 1994, con el objetivo de identificar los factores de riesgo biológico y socioeconómicos que con más frecuencia se asociaron; se estudiaron 32 "casos" y 53 "controles" de un universo de 521 nacidos vivos. Se demostró que la edad materna hasta 19 años y de 35 y más, la ganancia insuficiente de peso durante la gestación, el antecedente familiar de prematuridad, la amenaza de parto pretérmino y la ruptura prematura de las membranas, resultaron ser factores de riesgo, y esto no coincide con lo reportado por algunos autores en la evaluación de otros factores asociados.

  9. Update on normal tension glaucoma

    Directory of Open Access Journals (Sweden)

    Jyotiranjan Mallick

    2016-01-01

    Full Text Available Normal tension glaucoma (NTG is labelled when typical glaucomatous disc changes, visual field defects and open anterior chamber angles are associated with intraocular pressure (IOP constantly below 21 mmHg. Chronic low vascular perfusion, Raynaud's phenomenon, migraine, nocturnal systemic hypotension and over-treated systemic hypertension are the main causes of normal tension glaucoma. Goldmann applanation tonometry, gonioscopy, slit lamp biomicroscopy, optical coherence tomography and visual field analysis are the main tools of investigation for the diagnosis of NTG. Management follows the same principles of treatment for other chronic glaucomas: To reduce IOP by a substantial amount, sufficient to prevent disabling visual loss. Treatment is generally aimed to lower IOP by 30% from pre-existing levels to 12-14 mmHg. Betaxolol, brimonidine, prostaglandin analogues, trabeculectomy (in refractory cases, systemic calcium channel blockers (such as nifedipine and 24-hour monitoring of blood pressure are considered in the management of NTG. The present review summarises risk factors, causes, pathogenesis, diagnosis and management of NTG.

  10. The study and design of tension controller

    Science.gov (United States)

    Jun, G.; Lamei, X.

    2018-02-01

    Tension control is a wide used technology in areas such as textiles, paper and plastic films. In this article, the tension control system release and winding process is analyzed and the mathematical model of tension control system is established, and a high performance tension controller is designed. In hardware design, STM32F130 single chip microcomputer is used as the control core, which has the characteristics of fast running speed and rich peripheral features. In software design, μC/OS-II operating system is introduced to improve the efficiency of single chip microcomputer, and enhance the independence of each module, and make development and maintenance more convenient. The taper tension control is adopted in the winding part, which can effectively solve the problem of rolling shrinkage. The results show that the tension controller has the characteristics of simple structure, easy operation and stable performance.

  11. Soft-tissue tension total knee arthroplasty.

    Science.gov (United States)

    Asano, Hiroshi; Hoshino, Akiho; Wilton, Tim J

    2004-08-01

    It is far from clear how best to define the proper strength of soft-tissue tensioning in total knee arthroplasty (TKA). We attached a torque driver to the Monogram balancer/tensor device and measured soft-tissue tension in full extension and 90 degrees flexion during TKA. In our surgical procedure, when we felt proper soft-tissue tension was being applied, the mean distraction force was noted to be 126N in extension and 121N in flexion. There was no significant correlation between soft-tissue tension and the postoperative flexion angle finally achieved. To the best of our knowledge, this is the first study to assess the actual distraction forces in relation to soft-tissue tension in TKA. Further study may reveal the most appropriate forces to achieve proper soft-tissue tension in the wide variety of circumstances presenting at knee arthroplasty.

  12. The Equilibrium Spreading Tension of Pulmonary Surfactant

    OpenAIRE

    Dagan, Maayan P.; Hall, Stephen B.

    2015-01-01

    Monomolecular films at an air/water interface coexist at the equilibrium spreading tension (γe) with the bulk phase from which they form. For individual phospholipids, γe is single-valued, and separates conditions at which hydrated vesicles adsorb from tensions at which overcompressed monolayers collapse. With pulmonary surfactant, isotherms show that monolayers compressed on the surface of bubbles coexist with the three-dimensional collapsed phase over a range of surface tensions. γe therefo...

  13. Ley marco de aseguramiento universal en salud, bajo la lupa

    Directory of Open Access Journals (Sweden)

    Leoncio Díaz

    2009-04-01

    Full Text Available La Ley Marco de Aseguramiento Universal en Salud, concebida en el marco del modelo neoliberal conservador, excluyente y polarizante, fue aprobada en circunstancias en la que persisten grandes contrastes entre sistemas de salud. Por un lado, los países que mantienen subsistemas inconexos y privatizados y, por otro, los que unificados y bajo la responsabilidad del Estado, garantizan a todos el acceso integral, gratuito y de calidad a los servicios de salud. En América y el Caribe, existen países cuyos pobladores carecen de derechos y posibilidades, evidenciando las profundas inequidades que mantienen en exclusión a la mayoría pobre y de extrema pobreza, entre ellos, el Perú muestra indicadores de salud que aún se mantienen en cifras alarmantes y por debajo de los que presentan otras realidades en el mundo. En las últimas tres décadas hubo ensayos frustros de reformas, como la integración funcional del Ministerio de Salud con el Instituto Peruano de Seguridad Social, o el Sistema Nacional Coordinado y Descentralizado en Salud. Actualmente se formula la Ley Marco de Aseguramiento Universal, que mantiene los actuales subsistemas sin variación alguna y con sus propias autonomías, ensayando pilotos, estableciendo planes parciales, implementándola de manera progresiva, priorizando la privatización y debilitando la función rectora del Ministerio de Salud, al crear una superintendencia omnipotente, lo cual continuará permitiendo la exclusión social de más de 9 millones de peruanos. Existe, por tanto, la necesidad de plantear la unificación de los subsistemas, para construir un Sistema Único de Salud, capaz de otorgar salud plena, integral, de calidad y sin costo alguno al 100% de ciudadanos.

  14. Capital intelectual bajo el modelo de e-commerce

    Directory of Open Access Journals (Sweden)

    Gladys Rodríguez

    2009-09-01

    Full Text Available Hoy el mundo está cambiando de una economía basada en el acero, automóviles y carreteras hacia una nueva economía construida con base en silicio, computadoras y redes. Esta revolución tecnológica no se limita a modificar los equipos, los productos, las trayectorias tecnológicas y el modelo organizativo. Sino, como en todo cambio de paradigma hay un proceso de desmantelamiento de lo establecido y la construcción de un nuevo conjunto de principios. Hoy ese nuevo paradigma se fundamenta en el conocimiento, la pericia y sobre todo el talento del hombre. Por tanto, el objetivo principal es describir la importancia que tiene el capital intelectual en las organizaciones de e-commerce. La metodología empleada consistió en una revisión teórica con base a la literatura especializada de autores tales como: Edvinsson y Malone (1998, Brooking (1997, Luz Clara (2001, Merino (2004 y Añez (2005: orientándose hacia el capital intelectual bajo el esquema de negocios de organizaciones de e-commerce. Entre los resultados se destacan dos propuestas: una que describe el proceso de transformación de un negocio tradicional a un negocio de e-commerce sobre la base del capital intelectual; la otra, referida a indicar estrategias gerenciales que apuntan a identificar y evaluar la relación del capital intelectual en cuanto a las innovaciones/ respuestas a los cambios exigidos por el proceso de globalización en el marco de organizaciones de e-commerce.

  15. Actin filaments as tension sensors.

    Science.gov (United States)

    Galkin, Vitold E; Orlova, Albina; Egelman, Edward H

    2012-02-07

    The field of mechanobiology has witnessed an explosive growth over the past several years as interest has greatly increased in understanding how mechanical forces are transduced by cells and how cells migrate, adhere and generate traction. Actin, a highly abundant and anomalously conserved protein, plays a large role in forming the dynamic cytoskeleton that is so essential for cell form, motility and mechanosensitivity. While the actin filament (F-actin) has been viewed as dynamic in terms of polymerization and depolymerization, new results suggest that F-actin itself may function as a highly dynamic tension sensor. This property may help explain the unusual conservation of actin's sequence, as well as shed further light on actin's essential role in structures from sarcomeres to stress fibers. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Normal-tension glaucoma (Low-tension glaucoma)

    Science.gov (United States)

    Anderson, Douglas R

    2011-01-01

    Glaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP), with the degree and rate of damage depending on the IOP and presumably the degree of abnormal physiology. Diagnosis of normal-tension glaucoma (NTG), defined as glaucoma without a clearly abnormal IOP, depends on recognizing symptoms and signs associated with optic nerve vulnerability, in addition to absence of other explanations for disc abnormality and visual field loss. Among the findings are a halo or crescent of absence of retinal pigment epithelium around the disc, bilateral pre-chiasmal visual field defects, splinter hemorrhages at the disc margin, vascular dysregulation (low blood pressure, cold hands and feet, migraine headache with aura, and the like), or a family history of glaucoma. Possibly relevant, is a history of hemodynamic crisis, arterial obstructive disease, or sleep apnea. Neurological evaluation with imaging is needed only for atypical cases or ones that progress unexpectedly. Management follows the same principle of other chronic glaucomas, to lower the IOP by a substantial amount, enough to prevent disabling visual loss. However, many NTG cases are non-progressive. Therefore, it may often be wisein mild cases to determine whether the case is progressive and the rate of progression before deciding on how aggressivene to be with therapy. Efforts at neuroprotection and improvement in blood flow have not yet been shown effective. PMID:21150042

  17. Normal-tension glaucoma (Low-tension glaucoma

    Directory of Open Access Journals (Sweden)

    Anderson Douglas

    2011-12-01

    Full Text Available Glaucoma is now considered an abnormal physiology in the optic nerve head that interacts with the level of intraocular pressure (IOP, with the degree and rate of damage depending on the IOP and presumably the degree of abnormal physiology. Diagnosis of normal-tension glaucoma (NTG, defined as glaucoma without a clearly abnormal IOP, depends on recognizing symptoms and signs associated with optic nerve vulnerability, in addition to absence of other explanations for disc abnormality and visual field loss. Among the findings are a halo or crescent of absence of retinal pigment epithelium around the disc, bilateral pre-chiasmal visual field defects, splinter hemorrhages at the disc margin, vascular dysregulation (low blood pressure, cold hands and feet, migraine headache with aura, and the like, or a family history of glaucoma. Possibly relevant, is a history of hemodynamic crisis, arterial obstructive disease, or sleep apnea. Neurological evaluation with imaging is needed only for atypical cases or ones that progress unexpectedly. Management follows the same principle of other chronic glaucomas, to lower the IOP by a substantial amount, enough to prevent disabling visual loss. However, many NTG cases are non-progressive. Therefore, it may often be wisein mild cases to determine whether the case is progressive and the rate of progression before deciding on how aggressivene to be with therapy. Efforts at neuroprotection and improvement in blood flow have not yet been shown effective.

  18. Traumatic tension pneumocephalus: Two case reports

    Directory of Open Access Journals (Sweden)

    Abubaker Al-Aieb

    2017-01-01

    Conclusions: These are two rare cases with posttraumatic tension pneumocephalus treated conservatively with a favorable outcome. Early diagnosis of tension pneumocephalus is a crucial step to facilitate early recovery; however, the associated injuries need attention as they could influence the hospital course.

  19. Embracing Tensions in Feminist Organizational Communication Pedagogies

    Science.gov (United States)

    Linabary, Jasmine R.; Long, Ziyu; Mouton, Ashton; Rao, Ranjani L.; Buzzanell, Patrice M.

    2017-01-01

    Feminist pedagogies hold potential to create more inclusive and transformative classrooms. Adopting a tension-centered approach, we draw on our individual and collective reflections on the design and instruction of a multi-section undergraduate organizational communication course to build an autoethnographic account of the tensions associated with…

  20. Tending the tensions in co-creation

    DEFF Research Database (Denmark)

    Phillips, Professor MSO Louise; Nordentoft, Helle Merete; Pedersen, Lektor Christina Hee

    -for-granted positive value. In the panel we de-romanticise “co-creation” and explore how it is enacted in particular organisational contexts, concentrating on context-specific tensions arising in the meeting between different knowledge forms and interests. These include tensions BETWEEN dialogic views of knowledge co-creation...

  1. Post-tensioning system surveillance program

    International Nuclear Information System (INIS)

    Drew, G.E.

    1979-01-01

    Nuclear power plant containment structure post-tensioning system tendon surveillance program is described in detail. Data collected over three yearly post-tensioning system Surveillance Programs is presented and evaluated to correlate anticipated stress losses with actual losses. In addition corrosion protected system performance is analyzed

  2. Tension and robustness in multitasking cellular networks.

    Directory of Open Access Journals (Sweden)

    Jeffrey V Wong

    Full Text Available Cellular networks multitask by exhibiting distinct, context-dependent dynamics. However, network states (parameters that generate a particular dynamic are often sub-optimal for others, defining a source of "tension" between them. Though multitasking is pervasive, it is not clear where tension arises, what consequences it has, and how it is resolved. We developed a generic computational framework to examine the source and consequences of tension between pairs of dynamics exhibited by the well-studied RB-E2F switch regulating cell cycle entry. We found that tension arose from task-dependent shifts in parameters associated with network modules. Although parameter sets common to distinct dynamics did exist, tension reduced both their accessibility and resilience to perturbation, indicating a trade-off between "one-size-fits-all" solutions and robustness. With high tension, robustness can be preserved by dynamic shifting of modules, enabling the network to toggle between tasks, and by increasing network complexity, in this case by gene duplication. We propose that tension is a general constraint on the architecture and operation of multitasking biological networks. To this end, our work provides a framework to quantify the extent of tension between any network dynamics and how it affects network robustness. Such analysis would suggest new ways to interfere with network elements to elucidate the design principles of cellular networks.

  3. Tension Pneumothorax following an Accidental Kerosene Poisoning ...

    African Journals Online (AJOL)

    Tension pneumothorax is a rare complication following an accidental kerosene poisoning. In such situation, a bed-side needle thoracocentesis is performed because of its potential of becoming fatal; hence its clinical importance. A case of 15 month old boy with tension pneumothorax following accidental kerosene ...

  4. Initial tension loss in cerclage cables.

    Science.gov (United States)

    Ménard, Jérémie; Émard, Maxime; Canet, Fanny; Brailovski, Vladimir; Petit, Yvan; Laflamme, George Y

    2013-10-01

    Cerclage cables, frequently used in the management of fractures and osteotomies, are associated with a high failure rate and significant loosening during surgery. This study compared the capacity to maintain tension of different types of orthopaedic cable systems. Multifilament Cobalt-Chrome (CoCr) cables with four different crimp/clamp devices (DePuy, Stryker, Zimmer and Smith&Nephew) and one non-metallic Nylon (Ny) cable from Kinamed were instrumented with a load cell to measure tension during insertion. Significant tension loss was observed with crimping for all cables (Ptensioner led to an additional unexpected tension loss (CoCr-DePuy: 18%, CoCr-Stryker: 29%, CoCr-Smith&Nephew: 33%, Ny: 46%, and CoCr-Zimmer: 52%). The simple CoCr (DePuy) cable system outperformed the more sophisticated locking devices due to its significantly better ability to prevent tension loss. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Dynamical modeling of surface tension

    International Nuclear Information System (INIS)

    Brackbill, J.U.; Kothe, D.B.

    1996-01-01

    In a recent review it is said that free-surface flows ''represent some of the difficult remaining challenges in computational fluid dynamics''. There has been progress with the development of new approaches to treating interfaces, such as the level-set method and the improvement of older methods such as the VOF method. A common theme of many of the new developments has been the regularization of discontinuities at the interface. One example of this approach is the continuum surface force (CSF) formulation for surface tension, which replaces the surface stress given by Laplace's equation by an equivalent volume force. Here, we describe how CSF might be made more useful. Specifically, we consider a derivation of the CSF equations from a minimization of surface energy as outlined by Jacqmin. This reformulation suggests that if one eliminates the computation of curvature in terms of a unit normal vector, parasitic currents may be eliminated For this reformulation to work, it is necessary that transition region thickness be controlled. Various means for this, in addition to the one discussed by Jacqmin are discussed

  6. Bilateral tension pneumothorax after acupuncture.

    Science.gov (United States)

    Mohammad, Nurashikin

    2018-04-19

    Acupuncture is an ancient complementary medicine which is currently used worldwide. Many serious adverse events have been reported which include a spectrum of mild-to-fatal complications. However, the level of awareness with regard to complications is still low both to physicians and patients. We report a 63-year-old who presented with acute shortness of breath 2 hours after having had acupuncture. On examination, there was absent breath sound heard on the left lung and slightly reduced breath sound on the right lung. She had type 1 respiratory failure. Urgent chest radiograph confirmed bilateral pneumothorax which was more severe on the left with tension pneumothorax and mediastinal shift. Chest tubes were inserted bilaterally after failed needle aspiration attempts. Subsequently, the pneumothoraces resolved, and she was discharged well. The bilateral pneumothoraces caused by acupuncture were curable but could have been potentially fatal if diagnosis was delayed. This case report adds to the limited current literature on the complications of acupuncture leading to bilateral pneumothoraces. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Multibreath alveolar oxygen tension imaging.

    Science.gov (United States)

    Clapp, Justin; Hamedani, Hooman; Kadlecek, Stephen; Xin, Yi; Shaghaghi, Hoora; Siddiqui, Sarmad; Rossman, Milton D; Rizi, Rahim R

    2016-10-01

    This study tested the ability of a multibreath hyperpolarized HP (3) He MRI protocol to increase the accuracy of regional alveolar oxygen tension (PA O2 ) measurements by lessening the influence of gas-flow artifacts. Conventional single-breath PA O2 measurement has been susceptible to error induced by intervoxel gas flow, particularly when used to study subjects with moderate-to-severe chronic obstructive pulmonary disease (COPD). Both single-breath and multibreath PA O2 imaging schemes were implemented in seven human subjects (one healthy, three asymptomatic smokers, and three COPD). The number and location of voxels with nonphysiologic PA O2 values generated by intervoxel gas flow were compared between the two protocols. The multibreath scheme resulted in a significantly lower total percentage of nonphysiologic PA O2 values (6.0%) than the single-breath scheme (13.7%) (P = 0.006). PA O2 maps showed several patterns of gas-flow artifacts that were present in the single-breath protocol but mitigated by the multibreath approach. Multibreath imaging also allowed for the analysis of slow-filling areas that presented no signal after a single breath. A multibreath approach enhances the accuracy and completeness of noninvasive PA O2 measurement by significantly lessening the proportion of nonphysiologic values generated by intervoxel gas flow. Magn Reson Med 76:1092-1101, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  8. Gastrothorax or tension pneumothorax: A diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Singh Sarvesh

    2011-01-01

    Full Text Available Gastrothorax, a rare complication following thoracoabdominal aortic aneurysm repair, is reported. The clinical features of a gastrothorax and tension pneumothorax are similar and thus, a gastrothorax can masquerade as a tension pneumothorax. The diagnosis is made by a high level of clinical suspicion, chest X-ray shows a distended stomach with air fluid levels and a computerised tomography is useful in assessing the diaphragm and establishing the positions of the various intra-abdominal organs. Also, the risk of an intercostal drainage tube placement and the role of nasogastric tube in avoiding the development of a tension gastrothorax is highlighted.

  9. El crecimiento y desarrollo ante la prematuridad y el bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Christine Baccarat de Godoy Martins

    2015-09-01

    Full Text Available Objetivo: Realizar una revisión bibliográfica sobre el crecimiento y desarrollo de prematuros y/o de bajo peso al nacer. Metodología: Se utilizaron las bases de datos lilacs, medline y scielo. Se encontraron 64 trabajos: 10 publicados en 2005, 10 en 2006, 12 en 2007, 16 en 2008, 8 en 2009 y 8 en 2010. Las publicaciones halladas pertenecían a las áreas de medicina (59,4%, nutrición (7,8%, enfermería (7,8%, salud pública (7,8%, psicología (6,2%, epidemiología (4,7%, fisiología (3,1% y fonoaudiología (3,1%. Resultados:Los textos encontrados permitieron la organización del conocimiento producido según las siguientes categorías de análisis: Factores asociados al bajo peso en el nacimiento/prematuridad; Repercusiones del bajo peso en el nacimiento/prematuridad para el crecimiento y desarrollo y medidas de prevención; y Supervivencia de los recién nacidos prematuros o de bajo peso. Conclusión: Los niños nacidos prematuramente y de bajo peso generalmente presentan déficit de desarrollo. Un acompañamiento postnatal centrado en el crecimiento y desarrollo es fundamental.

  10. Influencia de la sobremaduración en las propiedades mecánicas y comportamiento a corrosión bajo tensión de una aleación de aluminio 7075 T6

    Directory of Open Access Journals (Sweden)

    Badía, J. M.

    2004-04-01

    Full Text Available The effect of a reageing heat treatment following a T6 temper on the mechanical properties and the stress corrosion cracking behaviour (SCC on the EN AW 7075 aluminium alloy is studied. The reageing time was 27 hours for all the temperatures used: 147, 152 and 163 ºC; this last temperature is indicated in the MIL-H-6088F standard to obtain the T73 temper from the T6 temper. The mechanical properties and the stress corrosion behaviour are evaluated and, compared with the T6 and T73 tempers. The evolution of the microstructure is analysed with transmission electron microscopy (TEM and differential scanning calorimetry (DSC techniques, and related with the properties. The reageing following to the T6 temper made a more stable structure higher the temperature, and, consequently, lowing the stress corrosion susceptibility. For temperatures lower than 147 ºC, this diminution of stress corrosion susceptibility occurs without reducing the mechanical properties. So, the 147 ºC reageing heat treatment has better stress corrosion behaviour than the T6 temper, with similar mechanical properties. By the other hand, the stress corrosion susceptibility achieved with the 152 ºC reageing is slightly worse than the T73 one, but their mechanical properties are better.

    En este trabajo se estudia el efecto de la aplicación de una etapa de remaduración posterior al estado T6 sobre las propiedades mecánicas y el comportamiento a corrosión bajo tensiones de una aleación EN AW 7075. Todas las remaduraciones se dieron durante 27 horas a tres temperaturas distintas: 147, 152 y 163 ºC; esta última corresponde a la indicada por la norma MIL-H-6088F para la obtención del estado T73 a partir del estado T6. Se evalúan las propiedades mecánicas y a corrosión bajo tensiones de estos tratamientos, teniendo como referencia los tratamientos T6 y T73. Se analiza la evolución de la microestructura con técnicas de microscopia electrónica de transmisión (TEM y

  11. Managing Tensions And Forging Creative Synergies Between ...

    African Journals Online (AJOL)

    Managing Tensions And Forging Creative Synergies Between Indigenous And Modern Settlement Planning Concepts And Practices: Lessons For The Design And Planning For Sustainable Settlements And Built-Forms In Southern Africa.

  12. Tension perturbations of black brane spacetimes

    International Nuclear Information System (INIS)

    Traschen, Jennie; Fox, Daniel

    2004-01-01

    We consider black brane spacetimes that have at least one spatial translation Killing field that is tangent to the brane. A new parameter, the tension of a spacetime, is defined. The tension parameter is associated with spatial translations in much the same way that the ADM mass is associated with the time translation Killing field. In this work, we explore the implications of the spatial translation symmetry for small perturbations around a background black brane. For static-charged black branes we derive a law which relates the tension perturbation to the surface gravity times the change in the horizon area, plus terms that involve variations in the charges and currents. We find that as a black brane evaporates the tension decreases. We also give a simple derivation of a first law for black brane spacetimes. These constructions hold when the background stress-energy is governed by a Hamiltonian, and the results include arbitrary perturbative stress-energy sources

  13. Notch effects in uniaxial tension specimens

    International Nuclear Information System (INIS)

    Delph, T.J.

    1979-03-01

    Results of a literature survey on the effect of notches on the time-dependent failure of uniaxial tension specimens at elevated temperatures are presented. Particular attention is paid to the failure of notched specimens containing weldments

  14. Tension waves in tethered satellite cables

    Science.gov (United States)

    Lallman, F. J.

    1984-01-01

    A one-degree-of-freedom simulation of the Tethered Satellite System (TSS) was programmed using a distributed system model of the tether based on the one-dimensional wave equation. This model represents the time varying tension profile along the tether as the sum of two traveling waves of tension moving in opposite directions. A control loop was devised which combines a deployment rate command with the measured tension at the deployer to produce a smooth, stable rate of deployment of the subsatellite. Simulation results show a buildup of periodic bursts of high frequency oscillation in tension. This report covers the mathematical modelling and simulation results and explains the reason for the observed oscillations. The design of a possible vibration damping device is discussed.

  15. Social Change of Bajo Tribe Society in Karimunjawa: From "Sea Tribe" to "Land Tribe"

    Directory of Open Access Journals (Sweden)

    Titiek Suliyati

    2017-12-01

    The result of the research shows that there is a social change in Bajo society living permanently in Karimunjawa that is, the change of daily behavior in the society, social interaction with other tribes, values held by the society and social institution, structure and social classes. Social change occurring to Bajo society in Karimunjawa brings positive influences. The social changes among others are awareness towards the importance of education, Bajo society has new jobs other than fisherman, the increase of income, living standard, also modernization in fisheries system. The negative impact as a consequence of the social changes is faded culture, changes in life orientation and views of life, and consumerism in the society.

  16. RESPUESTAS CARDIOVASCULARES AL ENTRENAMIENTO DE FUERZA BAJO OCLUSIÓN VASCULAR [Cardiovascular responses to strength training under occlusive training

    Directory of Open Access Journals (Sweden)

    Sergio Benito Hernández

    2013-11-01

    Full Text Available El entrenamiento de la fuerza bajo oclusión vascular se muestra como una alternativa al entrenamiento de alta intensidad. El presente estudio muestra las respuestas cardiovasculares a este tipo de entrenamiento. 10 sujetos fueron sometidos a dos protocolos de entrenamiento oclusivo diferenciados por el peso levantado, (30% del peso máximo, post30, y 70% del peso máximo, post70. Se registraron los valores de tensión arterial sistólica (TAS, diastólica (TAD y frecuencia cardiaca (FC. Los resultados evidencian disminución significativa en TAS y TAD en el grupo post30 en 7 y 13 mm Hg respectivamente en referencia a los valores basales (p<0.05, resultando un descenso muy significativo en el grupo post70, 14 y 20 mm Hg respectivamente (p<0.005. Los valores de la FC no se vieron alterados por ninguno de los protocolos experimentales (p>0.05. Los efectos de tamaño para todos los grupos resultaron triviales (d<0.25. En conclusión los resultados del presente estudios presentan una tendencia a la reducción de la tensión arterial significativa en TAS y TAD en los protocolos de entrenamiento oclusivo, resultando más notable cuando se aplica la mayor intensidad de entrenamiento. Resultan necesarios más estudios que examinen el comportamiento de los parámetros cardiovasculares tras el entrenamiento de fuerza bajo oclusión vascular.AbstractOcclusive strength training is shown like an alternative to intensive training. Present study shown cardiovascular responses to this training. 10 subjects were subjected to two occlusion training protocols, differentiated by the weight lifted (30 % of maximum weight lifted, post30, and 70 % of maximum weight lifted, post70. The values of arterial systolic tension (TAS, diastolic (TAD and heart rate (FC were recorded. The results showing a significant decline in TAS and TAD after post30 of 7 and 13 mm Hg respectively from basis values (p<0.05, resulting a very significant decline in post70 group, 14 and 20 mm Hg

  17. Tension Hydrothorax Related to Disseminated Endometriosis

    Directory of Open Access Journals (Sweden)

    AnnaKate Deal, MD

    2016-01-01

    Full Text Available We present the case of a 34-year-old woman presenting to the emergency department (ED with dyspnea, cough, and fever. She was found to have a tension hydrothorax and was treated with ultrasound-guided thoracentesis in the ED. Subsequent inpatient evaluation showed the patient had disseminated endometriosis. Tension hydrothorax has not been previously described in the literature as a complication of this disease.

  18. Condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México

    Directory of Open Access Journals (Sweden)

    CERÓN-MIRELES PRUDENCIA

    1997-01-01

    Full Text Available Objetivo. Estudiar la asociación entre condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México. Material y métodos. Se encuestaron 2 623 trabajadoras que atendieron sus partos en tres grandes hospitales de la Ciudad de México en 1992. Se obtuvo información sobre los principales factores biológicos y sociales que se asocian al bajo peso al nacer; asimismo, se determinó el estrés ocupacional utilizando el instrumento desarrollado por Karasek. Se utilizaron modelos de regresión logística para evaluar la relación de las condiciones de trabajo con el bajo peso al nacer, controlando por variables confusoras. Resultados. El bajo peso al nacer fue más alto en trabajadoras con jornadas mayores a 50 horas semanales (RM= 1.6; IC= 1.17, 2.28 y con conflictos laborales (RM= 1.5; IC= 1.0, 2.25. La falta de apoyo social tangible fue identificado como un factor de riesgo de bajo peso al nacer (RM= 1.7; IC= 1.20, 2.33. Las medidas preventivas laborales como el cambio de tareas, disminución de la jornada y las salidas por enfermedad no mostraron un efecto benéfico en el peso al nacer, a excepción de la licencia de maternidad; las madres que no la tuvieron mostraron una probabilidad 2.2 veces mayor para bajo peso al nacer (IC= 1.66, 2.93. Conclusiones. Estos hallazgos resaltan la importancia de identificar los factores de riesgo ocupacional en el embarazo..

  19. Density and surface tension of ionic liquids.

    Science.gov (United States)

    Kolbeck, C; Lehmann, J; Lovelock, K R J; Cremer, T; Paape, N; Wasserscheid, P; Fröba, A P; Maier, F; Steinrück, H-P

    2010-12-30

    We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf(2)N](-))-based and 12 1-methyl-3-octylimidazolium ([C(8)C(1)Im](+))-based ionic liquids (ILs) with the vibrating tube and the pendant drop method, respectively. This comprehensive set of ILs was chosen to probe the influence of the cations and anions on density and surface tension. When the alkyl chain length in the [C(n)C(1)Im][Tf(2)N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease in density is observed. The surface tension initially also decreases but reaches a plateau for alkyl chain lengths greater than n = 8. Functionalizing the alkyl chains with ethylene glycol groups results in a higher density as well as a higher surface tension. For the dependence of density and surface tension on the chemical nature of the anion, relations are only found for subgroups of the studied ILs. Density and surface tension values are discussed with respect to intermolecular interactions and surface composition as determined by angle-resolved X-ray photoelectron spectroscopy (ARXPS). The absence of nonvolatile surface-active contaminants was proven by ARXPS.

  20. Oxygen tension level and human viral infections

    Energy Technology Data Exchange (ETDEWEB)

    Morinet, Frédéric, E-mail: frederic.morinet@sls.aphp.fr [Centre des Innovations Thérapeutiques en Oncologie et Hématologie (CITOH), CHU Saint-Louis, Paris (France); Université Denis Diderot, Sorbonne Paris Cité Paris, Paris (France); Casetti, Luana [Institut Cochin INSERM U1016, Paris (France); François, Jean-Hugues; Capron, Claude [Institut Cochin INSERM U1016, Paris (France); Laboratoire d' Hématologie, Hôpital Ambroise Paré, Boulogne (France); Université de Versailles Saint-Quentin en Yvelynes, Versailles (France); Pillet, Sylvie [Laboratoire de Bactériologie-Virologie-Hygiène, CHU de Saint-Etienne, Saint-Etienne (France); Université de Lyon et Université de Saint-Etienne, Jean Monnet, GIMAP EA3064, F-42023 Saint-Etienne, Lyon (France)

    2013-09-15

    The role of oxygen tension level is a well-known phenomenon that has been studied in oncology and radiotherapy since about 60 years. Oxygen tension may inhibit or stimulate propagation of viruses in vitro as well as in vivo. In turn modulating oxygen metabolism may constitute a novel approach to treat viral infections as an adjuvant therapy. The major transcription factor which regulates oxygen tension level is hypoxia-inducible factor-1 alpha (HIF-1α). Down-regulating the expression of HIF-1α is a possible method in the treatment of chronic viral infection such as human immunodeficiency virus infection, chronic hepatitis B and C viral infections and Kaposi sarcoma in addition to classic chemotherapy. The aim of this review is to supply an updating concerning the influence of oxygen tension level in human viral infections and to evoke possible new therapeutic strategies regarding this environmental condition. - Highlights: • Oxygen tension level regulates viral replication in vitro and possibly in vivo. • Hypoxia-inducible factor 1 (HIF-1α) is the principal factor involved in Oxygen tension level. • HIF-1α upregulates gene expression for example of HIV, JC and Kaposi sarcoma viruses. • In addition to classical chemotherapy inhibition of HIF-1α may constitute a new track to treat human viral infections.

  1. Toward a general psychological model of tension and suspense.

    Science.gov (United States)

    Lehne, Moritz; Koelsch, Stefan

    2015-01-01

    Tension and suspense are powerful emotional experiences that occur in a wide variety of contexts (e.g., in music, film, literature, and everyday life). The omnipresence of tension and suspense suggests that they build on very basic cognitive and affective mechanisms. However, the psychological underpinnings of tension experiences remain largely unexplained, and tension and suspense are rarely discussed from a general, domain-independent perspective. In this paper, we argue that tension experiences in different contexts (e.g., musical tension or suspense in a movie) build on the same underlying psychological processes. We discuss key components of tension experiences and propose a domain-independent model of tension and suspense. According to this model, tension experiences originate from states of conflict, instability, dissonance, or uncertainty that trigger predictive processes directed at future events of emotional significance. We also discuss possible neural mechanisms underlying tension and suspense. The model provides a theoretical framework that can inform future empirical research on tension phenomena.

  2. Serie Madera para construcción La madera certificada bajo el concepto del triple resultado

    OpenAIRE

    Camacho-Cornejo, Diego; Moya-Roque, Róger

    2012-01-01

    A nivel mundial existe una tendencia de utilización de los productos certificados de madera bajo el concepto de triple resultado. En Costa Rica, diferentes empresas trabajan bajo este concepto. Es por ello que el presente trabajo tiene como objetivo mostrar el desarrollo de la madera certificada en Costa Rica, estableciendo la importancia de utilizar este tipo de madera, las ventajas de utilizarla en relación a aquella que no presenta esta certificación. Así mismo se presenta un detalle de la...

  3. LA INSATISFACCIÓN LABORAL COMO FACTOR DEL BAJO RENDIMIENTO DEL TRABAJADOR

    OpenAIRE

    Granda Carazas, Segundo Eloy

    2014-01-01

    El tema "la insatisfacción laboral como factor del bajo rendimiento del trabajador" es importante, ya que se puede constatar que en algunas organizaciones, pese a sus significativos esfuerzos para ampliar y modernizar su infraestructura, afrontan problemas de rendimiento laboral. Este artículo se orienta a determinar en qué medida la insatisfacción laboral se asocia al bajo rendimiento laboral en una organización. Como factores constituyentes de la insatisfacción laboral se considerar...

  4. Tensiones residuales generadas en acero F-522 por distintos tipos de mecanizado

    Directory of Open Access Journals (Sweden)

    García-Navas, V.

    2005-08-01

    , como en el interior del material. En este trabajo se han medido, mediante difracción de rayos-X, las tensiones residuales en un acero F-522 templado y revenido, generadas por dos procesos de torneado (torneado duro convencional y torneado duro asistido por láser y dos procesos de rectificado (de afino y de producción. Asimismo, se ha estudiado la evolución a lo largo de la profundidad de la fracción volumétrica de austenita retenida, de la microestructura y de nanodureza con el objetivo de relacionar estos resultados con los estados de tensiones obtenidos para cada mecanizado. Se ha observado que el torneado genera fuertes tensiones de tracción en la superficie y el rectificado tensiones de compresión. Inmediatamente, bajo la superficie, el rectificado genera tensiones ligeramente tractivas o nulas, mientras que el torneado genera tensiones fuertemente compresivas. Estos resultados indican que el proceso óptimo de mecanizado (prescindiendo de consideraciones económicas sería aquel que combinase un torneado duro con un ligero rectificado final

  5. A novel approach to pipeline tensioner modeling

    Energy Technology Data Exchange (ETDEWEB)

    O' Grady, Robert; Ilie, Daniel; Lane, Michael [MCS Software Division, Galway (Ireland)

    2009-07-01

    As subsea pipeline developments continue to move into deep and ultra-deep water locations, there is an increasing need for the accurate prediction of expected pipeline fatigue life. A significant factor that must be considered as part of this process is the fatigue damage sustained by the pipeline during installation. The magnitude of this installation-related damage is governed by a number of different agents, one of which is the dynamic behavior of the tensioner systems during pipe-laying operations. There are a variety of traditional finite element methods for representing dynamic tensioner behavior. These existing methods, while basic in nature, have been proven to provide adequate forecasts in terms of the dynamic variation in typical installation parameters such as top tension and sagbend/overbend strain. However due to the simplicity of these current approaches, some of them tend to over-estimate the frequency of tensioner pay out/in under dynamic loading. This excessive level of pay out/in motion results in the prediction of additional stress cycles at certain roller beds, which in turn leads to the prediction of unrealistic fatigue damage to the pipeline. This unwarranted fatigue damage then equates to an over-conservative value for the accumulated damage experienced by a pipeline weld during installation, and so leads to a reduction in the estimated fatigue life for the pipeline. This paper describes a novel approach to tensioner modeling which allows for greater control over the velocity of dynamic tensioner pay out/in and so provides a more accurate estimation of fatigue damage experienced by the pipeline during installation. The paper reports on a case study, as outlined in the proceeding section, in which a comparison is made between results from this new tensioner model and from a more conventional approach. The comparison considers typical installation parameters as well as an in-depth look at the predicted fatigue damage for the two methods

  6. Emergency percutaneous needle decompression for tension pneumoperitoneum

    Directory of Open Access Journals (Sweden)

    Körner Markus

    2011-05-01

    Full Text Available Abstract Background Tension pneumoperitoneum as a complication of iatrogenic bowel perforation during endoscopy is a dramatic condition in which intraperitoneal air under pressure causes hemodynamic and ventilatory compromise. Like tension pneumothorax, urgent intervention is required. Immediate surgical decompression though is not always possible due to the limitations of the preclinical management and sometimes to capacity constraints of medical staff and equipment in the clinic. Methods This is a retrospective analysis of cases of pneumoperitoneum and tension pneumoperitoneum due to iatrogenic bowel perforation. All patients admitted to our surgical department between January 2005 and October 2010 were included. Tension pneumoperitoneum was diagnosed in those patients presenting signs of hemodynamic and ventilatory compromise in addition to abdominal distension. Results Between January 2005 and October 2010 eleven patients with iatrogenic bowel perforation were admitted to our surgical department. The mean time between perforation and admission was 36 ± 14 hrs (range 30 min - 130 hrs, between ER admission and begin of the operation 3 hrs and 15 min ± 47 min (range 60 min - 9 hrs. Three out of eleven patients had clinical signs of tension pneumoperitoneum. In those patients emergency percutaneous needle decompression was performed with a 16G venous catheter. This improved significantly the patients' condition (stabilization of vital signs, reducing jugular vein congestion, bridging the time to the start of the operation. Conclusions Hemodynamical and respiratory compromise in addition to abdominal distension shortly after endoscopy are strongly suggestive of tension pneumoperitoneum due to iatrogenic bowel perforation. This is a rare but life threatening condition and it can be managed in a preclinical and clinical setting with emergency percutaneous needle decompression like tension pneumothorax. Emergency percutaneous decompression is no

  7. Surface tension in soap films: revisiting a classic demonstration

    International Nuclear Information System (INIS)

    Behroozi, F

    2010-01-01

    We revisit a classic demonstration for surface tension in soap films and introduce a more striking variation of it. The demonstration shows how the film, pulling uniformly and normally on a loose string, transforms it into a circular arc under tension. The relationship between the surface tension and the string tension is analysed and presented in a useful graphical form. (letters and comments)

  8. Surface tension in soap films: revisiting a classic demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Behroozi, F [Department of Physics, University of Northern Iowa, Cedar Falls, IA 50614 (United States)], E-mail: behroozi@uni.edu

    2010-01-15

    We revisit a classic demonstration for surface tension in soap films and introduce a more striking variation of it. The demonstration shows how the film, pulling uniformly and normally on a loose string, transforms it into a circular arc under tension. The relationship between the surface tension and the string tension is analysed and presented in a useful graphical form. (letters and comments)

  9. Mentoring Preservice Teachers: Identifying Tensions and Possible Resolutions

    Science.gov (United States)

    Hudson, Peter; Hudson, Sue

    2018-01-01

    Tensions can occur in the mentor-mentee relationship during school-based professional experiences that require problem solving. What are the tensions for mentor teachers in preservice teacher education and how might these tensions be resolved? This qualitative study collected data from 31 high school mentor teachers about tensions experienced with…

  10. Exploratory experimental investigations on post-tensioned structural glass beams

    DEFF Research Database (Denmark)

    Louter, C.; Nielsen, Jens Henrik; Belis, J.

    2013-01-01

    This paper discusses two projects on post-tensioned glass beams, performed at EPFL and DTU, respectively. In these projects small scale glass beams (length of 1.5m and 1m) are post-tensioned by means of steel threaded rods tensioned at the beam ends. The purpose of post-tensioning glass beams...

  11. Estratificación del bajo peso al nacer desde un enfoque de determinantes sociales

    Directory of Open Access Journals (Sweden)

    Hilda María Delgado Acosta

    2013-03-01

    Full Text Available Fundamento: el área materno-infantil requiere de un enfoque en sus determinantes para aumentar el alcance estratégico de sus programas. Objetivo: estratificar el bajo peso al nacer en el municipio de Cienfuegos y caracterizar el bajo peso de acuerdo a determinantes sociales seleccionadas. Métodos: se realizó un estudio epidemiológico, descriptivo, correlacional sobre la estratificación del bajo peso al nacer en los consejos populares del municipio Cienfuegos, en el período comprendido entre los años 2003 y 2007. Los estratos se definieron según el valor de la media del índice de bajo peso al nacer en este periodo. Para realizar el análisis de las variables cualitativas en muestras independientes se utilizó la prueba de independencia u homogeneidad utilizada en el caso de dos muestras con resultado dicotómico o más. El procesamiento estadístico se realizó en el programa SPSS versión 15,0 y se utilizaron como medidas matemáticas para las variables cualitativas el porcentaje, y para las variables cuantitativas la media aritmética. La técnica estadística para relacionar las variables fue la prueba Chi-cuadrado. Resultados: se mostraron diferencias estadísticamente significativas entre los estratos de bajo, mediano y alto riesgo, en el nivel de escolaridad, estado civil, ocupación, evaluación nutricional, hábito de fumar, antecedentes de bajo peso al nacer, período ínter genésico. La única enfermedad asociada que mostró diferencias entre ellos fue la hipertensión gestacional. Conclusiones: el bajo peso al nacer continúa siendo un serio problema de salud en el municipio Cienfuegos, cuestión esta que debe ser abordada desde sus determinantes para realizar intervenciones futuras y el logro de mejores resultados.

  12. On relation between the quark-gluon bag surface tension and the colour tube string tension

    International Nuclear Information System (INIS)

    Bugaev, K.A.; Zinovjev, G.M.

    2010-01-01

    We revisit the bag phenomenology of deconfining phase transition aiming to replenish it by introducing systematically the bag surface tension. Comparing the free energies of such bags and the strings confining the static quark-antiquark pair, we express the string tension in terms of the bag surface tension and the bulk pressure in order to estimate the bag characteristics using the lattice QCD (LQCD) data. Our analysis of the bag entropy density demonstrates that the surface tension coefficient is amazingly negative at the cross-over (continuous transition). The approach developed allows us to naturally account for an origin of a pronounced maximum (observed in the LQCD studies) in the behaviour of heavy quark-antiquark pair entropy. The vicinity of the (tri-)critical endpoint is also analyzed to clarify the meaning of vanishing surface tension coefficient.

  13. Factores nutricionales maternos y el bajo peso al nacer en un área de salud

    Directory of Open Access Journals (Sweden)

    Arley Rey Vilchez

    2013-01-01

    Full Text Available Fundamento: el bajo peso al nacer es multifactorial y se atribuye a causas maternas, fetales y ambientales. Los hábitos alimentarios inadecuados unidos a otros factores nutricionales maternos son determinantes. Objetivo: identificar los factores nutricionales maternos relacionados con el bajo peso al nacer en pacientes del Área I del municipio Cienfuegos. Métodos: se realizó un estudio analítico, retrospectivo, de casos y controles entre enero 2006 y diciembre 2008. Se estudiaron 50 madres de recién nacidos bajo peso (casos y 100 madres de niños normopesos (controles a razón de 2 por cada caso, seleccionadas del registro de nacimientos del área. Se revisaron las historias clínicas obstétricas y se entrevistó a cada paciente para evaluar sus hábitos alimentarios según frecuencia de comidas y grupos de alimentos consumidos. El procesamiento de la información se realizó utilizando el programa estadístico SPSS versión 15,0. Los resultados se presentaron en tablas con frecuencias absolutas, porcentajes y resultados de las técnicas estadísticas empleadas. Resultados: se comportaron como factores de riesgo: la edad materna, el estado nutricional al inicio del embarazo, la ganancia de peso durante la gestación y la hemoglobina del tercer trimestre. Las mujeres con hábitos alimentarios inestables e insuficientes tuvieron 33 veces más probabilidades de tener neonatos bajo peso y las que refirieron dietas no saludables según grupos de alimentos consumidos tuvieron 9 veces más riesgo. Conclusiones: los factores nutricionales maternos influyeron en la incidencia del bajo peso al nacer, fundamentalmente los hábitos alimentarios inadecuados.

  14. Factores de riesgo de bajo peso al nacer en un hospital cubano, 1997-2000

    Directory of Open Access Journals (Sweden)

    Escobar José Andrés Cabrales

    2002-01-01

    Full Text Available Objetivo. Identificar qué factores de riesgo materno durante el embarazo se asocian a la incidencia de bajo peso al nacer (menos de 2 500 g. Métodos. Se diseñó un estudio de casos y testigos con 764 casos de nacimiento simple con un peso al nacer de menos de 2 500 g, y 1 437 testigos del Hospital Gineco-Obstétrico Provincial de Sancti Spíritus, Cuba, durante el cuatrienio de 1997-2000. Los datos se obtuvieron de historias clínicas, registros de partos y entrevistas personales con las madres. Se realizó un análisis con dos variables y se controlaron los posibles factores de confusión mediante regresión logística dicotómica con el programa SPSS. Se usó un modelo final de múltiples variables para identificar los factores de riesgo maternos asociados con el bajo peso al nacer. Resultados. El análisis con múltiples variables mostró una asociación significativa del bajo peso al nacer con la presencia de anemia en la madre cuando se detectó el embarazo, la sepsis urinaria durante el embarazo, el asma bronquial, un aumento de peso materno menor de 8 kg durante todo el embarazo, el hábito de fumar durante el mismo, antecedentes de bajo peso al nacer en partos anteriores, la presencia de hipertensión arterial desde antes de la gestación y la consulta prenatal extemporánea. Conclusiones. A partir de estos resultados se concluyó que, independientemente de la medida de impacto utilizada, es importante tratar de disminuir los factores de riesgo identificados a fin de reducir la incidencia del bajo peso al nacer en la provincia de Sancti Spíritus.

  15. Factores de riesgo de bajo peso al nacer en un hospital cubano, 1997-2000

    Directory of Open Access Journals (Sweden)

    José Andrés Cabrales Escobar

    2002-09-01

    Full Text Available Objetivo. Identificar qué factores de riesgo materno durante el embarazo se asocian a la incidencia de bajo peso al nacer (menos de 2 500 g. Métodos. Se diseñó un estudio de casos y testigos con 764 casos de nacimiento simple con un peso al nacer de menos de 2 500 g, y 1 437 testigos del Hospital Gineco-Obstétrico Provincial de Sancti Spíritus, Cuba, durante el cuatrienio de 1997-2000. Los datos se obtuvieron de historias clínicas, registros de partos y entrevistas personales con las madres. Se realizó un análisis con dos variables y se controlaron los posibles factores de confusión mediante regresión logística dicotómica con el programa SPSS. Se usó un modelo final de múltiples variables para identificar los factores de riesgo maternos asociados con el bajo peso al nacer. Resultados. El análisis con múltiples variables mostró una asociación significativa del bajo peso al nacer con la presencia de anemia en la madre cuando se detectó el embarazo, la sepsis urinaria durante el embarazo, el asma bronquial, un aumento de peso materno menor de 8 kg durante todo el embarazo, el hábito de fumar durante el mismo, antecedentes de bajo peso al nacer en partos anteriores, la presencia de hipertensión arterial desde antes de la gestación y la consulta prenatal extemporánea. Conclusiones. A partir de estos resultados se concluyó que, independientemente de la medida de impacto utilizada, es importante tratar de disminuir los factores de riesgo identificados a fin de reducir la incidencia del bajo peso al nacer en la provincia de Sancti Spíritus.

  16. Fatigue in tension perpendicular to the grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Bo Uhre; Hoffmeyer, Preben

    1999-01-01

    Traditinally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduce in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In order to test the predictive validity of the result from the small tension specimens, fatigue experiments...

  17. Fatigue In Tension Perpendicular to the Grain

    DEFF Research Database (Denmark)

    Clorius, Christian Odin; Pedersen, Martin Uhre; Hoffmeyer, Preben

    2004-01-01

    Traditionally fatigue resistance is quantified as number of cycles to failure at a given stress level. A previous study by the authors showed that fatigue in compression parallel to the grain is governed partly by duration of load and partly by an effect of loading, i.e. a combination of a creep...... mechanism and a mechanism connected to damage introduced in the loading sequences. The purpose of the present study is to disentangle the effect of duration of load from the effect of load oscillation in fatigue in tension perpendicular to the grain. Fatigue experiments are made on small specimens...... and on dowel type joints with slotted in steel plates. In series of ten, the small specimens are taken to fatigue failure in uniform tension at square wave shaped load cycles at 0.01 Hz and 0.1 Hz. In arder to test the predictive validity of the result from the small tension specimens, fatigue experiments...

  18. Tensions between Teams and Their Leaders

    Directory of Open Access Journals (Sweden)

    J. David Johnson

    2016-10-01

    Full Text Available The intersection of teamwork and leadership results in tensions, dilemmas, and paradoxes for both individuals and for institutions such as simultaneously empowering individuals at the same time it frustrates them when our naive, cultural understanding of leadership centralizes power and values leaders who can impose their will and vision on others. Perhaps the fundamental paradox of teamwork and leadership is that the more leadership is focused on an individual the less likely a team’s potential will be realized. Six specific domains where tensions arise are: at team boundaries; culture; who is in charge, rationality/cognition; diversity; and collaborations. Three approaches - clarifying different levels of analysis, temporal factors, and overarching concepts - to resolving tensions are discussed. New conceptions of leadership and the importance of the larger cultural frame within which they are embedded are needed for the management of technology and innovation.

  19. Cellular control of connective tissue matrix tension.

    Science.gov (United States)

    Langevin, Helene M; Nedergaard, Maiken; Howe, Alan K

    2013-08-01

    The biomechanical behavior of connective tissue in response to stretching is generally attributed to the molecular composition and organization of its extracellular matrix. It also is becoming apparent that fibroblasts play an active role in regulating connective tissue tension. In response to static stretching of the tissue, fibroblasts expand within minutes by actively remodeling their cytoskeleton. This dynamic change in fibroblast shape contributes to the drop in tissue tension that occurs during viscoelastic relaxation. We propose that this response of fibroblasts plays a role in regulating extracellular fluid flow into the tissue, and protects against swelling when the matrix is stretched. This article reviews the evidence supporting possible mechanisms underlying this response including autocrine purinergic signaling. We also discuss fibroblast regulation of connective tissue tension with respect to lymphatic flow, immune function, and cancer. Copyright © 2013 Wiley Periodicals, Inc.

  20. Surface tension of normal and heavy water

    International Nuclear Information System (INIS)

    Straub, J.; Rosner, N.; Grigull, V.

    1980-01-01

    A Skeleton Table and simple interpolation equation for the surface tension of light water was developed by the Working Group III of the International Association for the Properties of Steam and is recommended as an International Standard. The Skeleton Table is based on all known measurements of the surface tension and individual data were weighted corresponding to the accuracy of the measurements. The form of the interpolation equation is based on a physical concept. It represents an extension of van der Waals-equation, where the exponent conforms to the 'Scaling Laws'. In addition for application purposes simple relations for the Laplace-coefficient and for the density difference between the liquid and gaseous phases of light water are given. The same form of interpolation equation for the surface tension can be used for heavy water, for which the coefficients are given. However, this equation is based only on a single set of data. (orig.) [de

  1. Tension Stiffened and Tendon Actuated Manipulator

    Science.gov (United States)

    Doggett, William R. (Inventor); Dorsey, John T. (Inventor); Ganoe, George G. (Inventor); King, Bruce D. (Inventor); Jones, Thomas C. (Inventor); Mercer, Charles D. (Inventor); Corbin, Cole K. (Inventor)

    2015-01-01

    A tension stiffened and tendon actuated manipulator is provided performing robotic-like movements when acquiring a payload. The manipulator design can be adapted for use in-space, lunar or other planetary installations as it is readily configurable for acquiring and precisely manipulating a payload in both a zero-g environment and in an environment with a gravity field. The manipulator includes a plurality of link arms, a hinge connecting adjacent link arms together to allow the adjacent link arms to rotate relative to each other and a cable actuation and tensioning system provided between adjacent link arms. The cable actuation and tensioning system includes a spreader arm and a plurality of driven and non-driven elements attached to the link arms and the spreader arm. At least one cable is routed around the driven and non-driven elements for actuating the hinge.

  2. Focal adhesions, stress fibers and mechanical tension

    Energy Technology Data Exchange (ETDEWEB)

    Burridge, Keith, E-mail: Keith_Burridge@med.unc.edu [Department of Cell Biology and Physiology, and Lineberger Comprehensive Cancer Center, 12-016 Lineberger, CB#7295, University of North Carolina, Chapel Hill, NC (United States); Guilluy, Christophe, E-mail: christophe.guilluy@univ-nantes.fr [Inserm UMR-S1087, CNRS UMR-C6291, L' institut du Thorax, and Université de Nantes, Nantes (France)

    2016-04-10

    Stress fibers and focal adhesions are complex protein arrays that produce, transmit and sense mechanical tension. Evidence accumulated over many years led to the conclusion that mechanical tension generated within stress fibers contributes to the assembly of both stress fibers themselves and their associated focal adhesions. However, several lines of evidence have recently been presented against this model. Here we discuss the evidence for and against the role of mechanical tension in driving the assembly of these structures. We also consider how their assembly is influenced by the rigidity of the substratum to which cells are adhering. Finally, we discuss the recently identified connections between stress fibers and the nucleus, and the roles that these may play, both in cell migration and regulating nuclear function. - Highlights: • The different types of stress fiber and focal adhesion are described. • We discuss the controversy about tension and assembly of these structures. • We describe the different models used to investigate assembly of these structures. • The influence of substratum rigidity is discussed. • Stress fiber connections to the nucleus are reviewed.

  3. Inclusion and Participation: Working with the Tensions

    Directory of Open Access Journals (Sweden)

    Gideon Calder

    2011-12-01

    Full Text Available Democracy is crucially about inclusion: a theory of democracy must account for who is to be included in the democratic process, how, and on what terms. Inclusion, if conceived democratically, is fraught with tensions. This article identifies three such tensions, arising respectively in: (i the inauguration of the democratic public; (ii enabling equal participation; and (iii the relationship between instrumental and non-instrumental accounts of democracy’s value. In each case, I argue, rather than seeking somehow to dissolve or avoid such tensions, theories of democracy should allow us to live with their implications reflexively: to work with them. Such tensions are counter-democratic to the extent that they derail what Nancy Fraser calls “participatory parity,” under which citizens count as “full partners in social interaction.” But the extent to which they do this is not itself dependent on points of paradox in the very idea of inclusion. Such parity relies on complex factors, social and economic, which democratic institutions and procedures will not by themselves address. To achieve full democratic inclusion we must already have addressed such factors; no account of democracy itself, however finely-tuned, will do this.

  4. Tension and relaxation in the individual.

    Science.gov (United States)

    Newbury, C R

    1979-06-01

    Increasing materialism in society is resulting in more wide spread nervous tension in all age groups. While some degree of nervous tension is necessary in everyday living, its adverse effects require that we must learn to bring it under control. Total tension is shown to have two components: a controllable element arising from factors in the environment and the inbuilt uncontrollable residue which is basic in the individual temperament. The effects of excessive or uncontrolled stress can be classified as 1) emotional reactions such as neurotic behaviour (anxiety hypochondria, hysteria, phobia, depression obsessions and compulsions) or psychotic behaviour and 2) psychosomatic reactions (nervous asthma, headache, insomnia, heart attack). Nervous energy can be wastefully expended by such factors as loss of temper, wrong attitudes to work, job frustration and marital strains. Relaxation is the only positive way to control undesirable nervous tension and its techniques require to be learned. A number of techniques (progressive relaxation, differential relaxation, hypnosis, the use of biofeedback, Yoga and Transcendental Meditation) are described and their application to dental practice is discussed.

  5. WORRY, ANXIETY AND TENSION — IMPORTANCE ...

    African Journals Online (AJOL)

    Enrique

    cognitive. Tension: Increased and unpleasant motor and psychological activity or a state of mental or ... MRC Research Unit on Anxiety and Stress. Disorders ... and brain imaging. Worry ... serve an adaptive function to the daily challenges of our environment. ... connection to physical symptoms ... Experience-conditioning.

  6. Surface Tension Measurements with a Smartphone

    Science.gov (United States)

    Goy, Nicolas-Alexandre; Denis, Zakari; Lavaud, Maxime; Grolleau, Adrian; Dufour, Nicolas; Deblais, Antoine; Delabre, Ulysse

    2017-01-01

    Smartphones are increasingly used in higher education and at university in mechanics, acoustics, and even thermodynamics as they offer a unique way to do simple science experiments. In this article, we show how smartphones can be used in fluid mechanics to measure surface tension of various liquids, which could help students understand the concept…

  7. Rebellion and Agrarian Tensions in Sierra Leone

    NARCIS (Netherlands)

    Peters, K.; Richards, P.

    2011-01-01

    This paper assesses the extent to which customary governance in Sierra Leone can be held responsible for an increasingly unstable two-class agrarian society. A case is made for regarding the civil war (1991–2002) as being an eruption of long-term, entrenched agrarian tensions exacerbated by chiefly

  8. Normal tension glaucoma and Alzheimer disease

    DEFF Research Database (Denmark)

    Bach-Holm, Daniella; Kessing, Svend Vedel; Mogensen, Ulla Brasch

    2012-01-01

    Purpose: To investigate whether normal tension glaucoma (NTG) is associated with increased risk of developing dementia/Alzheimer disease (AD). Methods: A total of 69 patients with NTG were identified in the case note files in the Glaucoma Clinic, University Hospital of Copenhagen (Rigshospitalet...

  9. Coexisting tensions between the 'traditionmodernity' and the ...

    African Journals Online (AJOL)

    Coexisting tensions between the 'traditionmodernity' and the 'sustainability- integration' approaches to urban development policy and planning practices in Botswana. ... exists at several levels and manifest in urban planning's preoccupation with the physicality of spatial forms, often justified in the embracing of globalization.

  10. Tension and Approximation in Poetic Translation

    Science.gov (United States)

    Al-Shabab, Omar A. S.; Baka, Farida H.

    2015-01-01

    Simple observation reveals that each language and each culture enjoys specific linguistic features and rhetorical traditions. In poetry translation difference and the resultant linguistic tension create a gap between Source Language and Target language, a gap that needs to be bridged by creating an approximation processed through the translator's…

  11. Transcutaneous oxygen tension in imminent foot gangrene

    DEFF Research Database (Denmark)

    Tønnesen, K H

    1978-01-01

    Transcutaneous oxygen tension at 44 degree C and maximal isotope clearance (90m Tc-pretechnetate + histramine) just proximal to the 1st toe and systolic toe blood pressure (strain gauge) were studied on a tilt table in patients with various degrees of obstructive arteriosclerotic disease. In legs...

  12. Internationalization and Global Tension: Lessons From History

    Science.gov (United States)

    Altbach, Philip G.; de Wit, Hans

    2015-01-01

    Increasing political and military tension in several parts of the world will inevitably affect international higher education. Nationalist, religious, and ideological conflicts challenge the original ideas of international cooperation and exchange in higher education as promoters of peace and mutual understanding and of global engagement. Since…

  13. Educational Leadership: Key Challenges and Ethical Tensions

    Science.gov (United States)

    Duignan, Patrick

    2007-01-01

    "Educational Leadership" is a major research book on contemporary leadership challenges for educational leaders. In this groundbreaking new work, educational leaders in schools, including teachers, are provided with ways of analysing and resolving common but complex leadership challenges. Ethical tensions inherent in these challenges are…

  14. Tension Builds over AFT Reform Agenda

    Science.gov (United States)

    Sawchuk, Stephen

    2012-01-01

    Can a teachers' union successfully be both a hardball-playing defender of its rights and a collaborative force for the common good? It is both a question of philosophy and, increasingly, one of policy direction for the American Federation of Teachers (AFT), whose biennial convention in Detroit showed delegates grappling with the tension between…

  15. Exact analytical density profiles and surface tension

    Indian Academy of Sciences (India)

    journal of. May 2005 physics pp. 785–801. Classical charged fluids at equilibrium near ... is provided by the excess surface tension for an air–water interface, which is determined ... the potential drop created by the electric layer which appears as soon as the fluid has ...... radii, by symmetry, the charge density profile is flat,.

  16. Bajo Peso al Nacer. Factores de riesgo y calidad de la atención Prenatal. Buenaventura. 2008-2009

    Directory of Open Access Journals (Sweden)

    Luis Enrique Gallardo-Ibarra

    2012-01-01

    Full Text Available Se realizó estudio descriptivo sobre Bajo Peso al Nacer, Área de Salud Buenaventura, bienio 2008-2009, sobre factores de riesgo y calidad de la atención médica recibida por las gestantes que aportaron recién nacidos bajo peso. Los datos estadísticos se obtuvieron mediante revisión de historias clínicas familiares, obstétricas y hospitalarias. Se emplearon métodos estadísticos histórico lógico, análisis y síntesis e inducción-deducción. Se obtuvo predominio del CIUR como variedad de Bajo Peso al Nacer, mostraron asociación con el bajo peso al nacer la valoración nutricional Bajo Peso materna al inicio de la gestación, insuficiente ganancia de peso, ingreso percápita bajo, malas condiciones de vivienda, antecedentes de dos o más abortos, multigestación, período intergenésico corto, HTA y sepsis cervicovaginal. La Atención Prenatal fue deficiente. No existió relación entre grupos de edades menores de 20 o mayor de 35 años y hábitos tóxicos con la aparición del bajo peso al nacer.

  17. Transitions of tethered chain molecules under tension.

    Science.gov (United States)

    Luettmer-Strathmann, Jutta; Binder, Kurt

    2014-09-21

    An applied tension force changes the equilibrium conformations of a polymer chain tethered to a planar substrate and thus affects the adsorption transition as well as the coil-globule and crystallization transitions. Conversely, solvent quality and surface attraction are reflected in equilibrium force-extension curves that can be measured in experiments. To investigate these effects theoretically, we study tethered chains under tension with Wang-Landau simulations of a bond-fluctuation lattice model. Applying our model to pulling experiments on biological molecules we obtain a good description of experimental data in the intermediate force range, where universal features dominate and finite size effects are small. For tethered chains in poor solvent, we observe the predicted two-phase coexistence at transitions from the globule to stretched conformations and also discover direct transitions from crystalline to stretched conformations. A phase portrait for finite chains constructed by evaluating the density of states for a broad range of solvent conditions and tensions shows how increasing tension leads to a disappearance of the globular phase. For chains in good solvents tethered to hard and attractive surfaces we find the predicted scaling with the chain length in the low-force regime and show that our results are well described by an analytical, independent-bond approximation for the bond-fluctuation model for the highest tensions. Finally, for a hard or slightly attractive surface the stretching of a tethered chain is a conformational change that does not correspond to a phase transition. However, when the surface attraction is sufficient to adsorb a chain it will undergo a desorption transition at a critical value of the applied force. Our results for force-induced desorption show the transition to be discontinuous with partially desorbed conformations in the coexistence region.

  18. Algas epífitas de Bajo Pepito, Isla Mujeres, Quintana Roo, México

    Directory of Open Access Journals (Sweden)

    L.I Quan-Young

    2006-06-01

    Full Text Available Epiphytic algae from Bajo Pepito, Isla Mujeres, Quintana Roo, México. A total of 96 epiphytic algae species were identified from Bajo Pepito, Quintana Roo, México. 60.4% (58 belonged to the Rhodophyta, 19.79% (19 to the Phaeophyta, 16.6% (16 to the Chlorophyta and 3.1% (3 to the Cyanophyta; 49 species (50.5% were found only in one month, while Heterosiphonia crispella was found in all of the sampled months. That species provided the largest contribution to the biomass of epiphytes. During January we registered the greater biommass and richness of epiphytes species, coincidently with high values of host species cover and rainfall. Rev. Biol. Trop. 54(2: 317-328. Epub 2006 Jun 01.

  19. Estudio de una Cronosecuencia de Suelos en el Bajo Cauca (Antioquia

    Directory of Open Access Journals (Sweden)

    Jaramillo J. Daniel F.

    1996-09-01

    Full Text Available En la región del Bajo Cauca, Antioquia, se estudiaron tres terrazas, a diferentes alturas, las cuales poseen diferencias apreciables entre la evolución de sus respectivos suelos. La terraza de mayor altura presentó los suelos más evolucionados: Typic Paleudult; la de mediana altura presentó suelos de incipiente evolución, clasificados como Typic Dystropept y la de menor altitud presentó suelos recientes, con muy bajo grado de evolución: Tropic Fluvaquent. Las diferencias en evolución observadas entre los suelos se deben a los largos intervalos de tiempo transcurridos entre la formación de los tres niveles de las terrazas. La fertilidad natural de los suelos desarrollados sobre las terrazas alta y media se puede calificar como baja a muy baja; por su parte, la terraza a menor altura posee alta fertilidad.

  20. DESARROLLO E IMPLEMENTACIÓN DE FOTOCONTROL TEMPORIZADO CON TECNOLOGÍA DE BAJO CONSUMO

    Directory of Open Access Journals (Sweden)

    Fredy Hernán Martínez Sarmiento

    2013-09-01

    Full Text Available En este trabajo se presenta el desarrollo e implementación de un fotocontrol con tecnología de bajo consumo desarrollado con un microcontrolador, el cual controla variables de tensión, luminosidad  y sincronización con la red, por medio de  una salida con modo PWM producir una salida de Vdc en el relé. El microcontrolador realiza un  muestreo análogo de voltaje sobre la onda sinusoidal y se hace un filtro de promedio móvil para eliminar ruido de la onda.La temporización se realiza cuando el contacto del relé está cerrado y el tiempo a temporizar es programado por el usuario el cual lo requiera, el fotocontrol presenta un modo de ultra bajo consumo en el microcontrolador con un supercap.

  1. Habilidades pre-escolares de los niños nacidos prematuramente y con bajo peso

    OpenAIRE

    Sasha A. Martínez-Espiet; Irene Sumaza Laborde; Leila Crespo Fernández; Maribel Campos Rivera; Frances Boulon Díaz

    2016-01-01

    RESUMEN: El objetivo de este estudio fue conocer el nivel de desarrollo en la etapa pre-escolar de un grupo de niños nacidos prematuramente y con bajo peso. Se evaluó un grupo 20 niños de cuatro años nacidos prematuramente y con bajo peso y un grupo de 20 niños nacidos luego de gestación completada y peso deseado utilizando la prueba de integración visual-motora Beery-Buktenica. Además, se administró el cuestionario del desarrollo Ages and Stages (ASQ-3) a las 40 madres. El análisis estadísti...

  2. Los exilios de católicos y arrianos bajo Leovigildo y Recaredo

    Directory of Open Access Journals (Sweden)

    Vallejo Girvés, Margarita

    2003-06-01

    Full Text Available In this paper we try to analyse the various topics of the exile that have been applied by the visigothic kings Leovigild and Reccared. It is known that most part of the individuals that had suffered this exile were ecclesiasticals, catholics under Leovigild and arians during Reccared, but all of them were of germanic origin.

    En este artículo se analizan los diversos tipos de exilio que aplicaron los monarcas visigodos Leovigildo y Recaredo. Se da la circunstancia de que la mayoría de ellos fueron eclesiásticos y que bajo Leovigildo lo sufrieron singularmente los católicos y los arríanos bajo Recaredo, pero en ambos casos todos los condenados son de origen germánico.

  3. Necessary Tension in Marine Risers Tension des colonnes montantes en mer

    Directory of Open Access Journals (Sweden)

    Lubinski A.

    2006-11-01

    Full Text Available The tension governing transverse static and dynamic deflections in a riser is not the actual tension but the so-called « effective tension » The concept of effective tension and effective compression is thoroughly explained, and means for calculating effective forces are given. Numerical examples are worked out for risers whose length is between 152 m (520 ft and 920 m (3020 ft. The reciprocal of maximum bending moment of the vicinity of the hall joint is plotted versus the effective tension of the ball joint. Bending moments used were obtained through use of static and dynamic computer programs applied ta a variety of conditions of wave loading, use or non-use of buoyant moterial sleeves, etc. The most important parameters affecting riser performance are the effective La tension régissant les déflections transversales statiques et dynamiques d'une colonne montante n'est pas la tension réelle mais ce qu'on appelle « la tension effective ». Le concept de tension ou de compression effective est expliqué en détail et la façon de calculer les forces effectives est indiquée dans cet article. Des exemples numériques sont développés pour des colonnes montantes de longueur comprise entre 152 m (520 ft et 920 m (3 020 ft. On a tracé la courbe de l'inverse du moment fléchissant en fonction de la tension effective à l'articulation. Les moments fléchissants utilisés ont été calculés par ordinateur en utilisant des programmes dynamiques et statiques pour des conditions variées d'action des vagues, la colonne montante étant ou non munie de manchettes de flottabilité, etc. Les deux paramètres les plus importants qui affectent le bon comportement d'une colonne montante sont la tension effective et la charge latérale.

  4. Bajo rendimiento escolar: una perspectiva desde el desarrollo del sistema nervioso

    Directory of Open Access Journals (Sweden)

    K. Shapiro Bruce, MD.

    2011-03-01

    Full Text Available El bajo rendimiento escolar es un problema frecuente y tiene múltiples causas; las alteraciones que lo caracterizan, se expresan fundamentalmente en las áreas de funcionamiento cognitivo, académico y conductual. El bajo rendimiento escolar es una vía final común de diferentes trastornos, etiologías y mecanismos. Es habitual la presencia de múltiples alteraciones, porque la disfunción cerebral en la niñez generalmente afecta a muchas funciones. Consecuente con lo anterior, los programas de manejo deben ser individualizados, comprensivos e incorporar aspectos del niño en particular, la escuela y la familia. La planificación del tratamiento incluye, educación y entrenamiento de los padres, adecuaciones académicas, técnicas para mantener la autoestima y un enfoque psicofarmacológico. Es necesario monitorear en forma continua los programas de manejo especialmente para detectar comorbilidades importantes que puedan emerger, para realizar modificaciones que se adecuen a los cambios en las demandas académicas y sociales a las diferentes edades del niño y para proveer de información actualizada. Las consecuencias que tenga el bajo rendimiento escolar para el niño dependerán en medida importante de las alteraciones subyacentes. El personal de salud tiene múltiples roles en la prevención, detección, diagnóstico y manejo del niño con bajo rendimiento escolar.

  5. Actualización en el manejo del colesterol hdl bajo

    Directory of Open Access Journals (Sweden)

    Rigotti R. Attilio, Dr.

    2012-11-01

    Full Text Available Los niveles plasmáticos bajos de colesterol transportado en las lipoproteínas de alta densidad (HDL constituyen un elemento independiente de riesgo cardiovascular ateroesclerótico. Algunos protocolos clínicos enfocados en el manejo farmacológico de los niveles bajos de colesterol HDL en pacientes de alto riesgo cardiovascular han mostrado resultados favorables. Por otro lado, existen nuevas formulaciones de la niacina, el agente farmacológico disponible más efectivo para el manejo del colesterol HDL bajo, y se están desarrollando nuevos fármacos más potentes para aumentar los niveles plasmáticos de colesterol HDL. En el futuro, nuevos medicamentos que modulen el metabolismo de HDL y demuestren beneficio sobre el control del riesgo cardiovascular ateroesclerótico, podrían mejorar aún más el manejo actual de esta condición patológica que se basa esencialmente en el uso de estatinas.

  6. Perfil cognitivo de niños con rendimientos bajos en comprensión lectora

    Directory of Open Access Journals (Sweden)

    Lorena Canet-Juric

    2013-10-01

    Full Text Available La mayoría de los niños con dificultades en la comprensión lectora poseen rendimientos inferiores en un conjunto de procesos cognitivos. El objetivo del presente estudio es establecer un perfil cognitivo asociado al bajo rendimiento en comprensión lectora en relación a la habilidad de monitoreo, a la producción de inferencias, al vocabulario, a la amplitud de memoria de trabajo y a la capacidad inhibitoria, en niños hispanoparlantes. Para ello se administraron tareas correspondientes a dichos procesos en niños con altos y bajos rendimientos en comprensión lectora. Los resultados mostraron que si bien los niños con mala comprensión presentan bajos rendimientos en estas habilidades, no puede establecerse un perfil consistente ya que hay niños con problemas en comprensión que presentan normal o superior rendimiento en algunas de estas habilidades cognitivas.

  7. Assessment and reduction of diaphragmatic tension during hiatal hernia repair.

    Science.gov (United States)

    Bradley, Daniel Davila; Louie, Brian E; Farivar, Alexander S; Wilshire, Candice L; Baik, Peter U; Aye, Ralph W

    2015-04-01

    During hiatal hernia repair there are two vectors of tension: axial and radial. An optimal repair minimizes the tension along these vectors. Radial tension is not easily recognized. There are no simple maneuvers like measuring length that facilitate assessment of radial tension. The aims of this project were to: (1) establish a simple intraoperative method to evaluate baseline tension of the diaphragmatic hiatal muscle closure; and, (2) assess if tension is reduced by relaxing maneuvers and if so, to what degree. Diaphragmatic characteristics and tension were assessed during hiatal hernia repair with a tension gage. We compared tension measured after hiatal dissection and after relaxing maneuvers were performed. Sixty-four patients (29 M:35F) underwent laparoscopic hiatal hernia repair. Baseline hiatal width was 2.84 cm and tension 13.6 dag. There was a positive correlation between hiatal width and tension (r = 0.55) but the strength of association was low (r (2) = 0.31). Four different hiatal shapes (slit, teardrop, "D", and oval) were identified and appear to influence tension and the need for relaxing incision. Tension was reduced by 35.8 % after a left pleurotomy (12 patients); by 46.2 % after a right crural relaxing incision (15 patients); and by 56.1 % if both maneuvers were performed (6 patients). Tension on the diaphragmatic hiatus can be measured with a novel device. There was a limited correlation with width of the hiatal opening. Relaxing maneuvers such as a left pleurotomy or a right crural relaxing incision reduced tension. Longer term follow-up will determine whether outcomes are improved by quantifying and reducing radial tension.

  8. Thermal Analysis of Bending Under Tension Test

    DEFF Research Database (Denmark)

    Ceron, Ermanno; Martins, Paulo A.F.; Bay, Niels

    2014-01-01

    during testing is similar to the one in the production tool. A universal sheet tribo-tester has been developed, which can run multiple tests automatically from coil. This allows emulating the temperature increase as in production. The present work performs finite element analysis of the evolution......The tribological conditions in deep drawing can be simulated in the Bending Under Tension test to evaluate the performance of new lubricants, tool materials, etc. Deep drawing production with automatic handling runs normally at high rate. This implies considerable heating of the tools, which...... sometimes can cause lubricant film breakdown and galling. In order to replicate the production conditions in bending under tension testing it is thus important to control the tool/workpiece interface temperature. This can be done by pre-heating the tool, but it is essential that the interface temperature...

  9. Quantum surface tension in ideal gases

    International Nuclear Information System (INIS)

    Sisman, A.

    2005-01-01

    Due to wave character of atoms, an ideal gas confined in a finite domain exhibits Casimir like size effects. These effects become appreciable in a domain with at least one dimension in the order of micron. On this scale, thermodynamic state functions of an ideal gas become shape and size dependent and some new effects appear. In the literature, only some domains of regular shapes have been considered. In this study, the results are generalized to a domain of an arbitrary shape by using Weyl s conjecture for density of states. It is seen that free energy expression of an ideal Maxwellian gas consists of a classical volume dependent term and also a quantum originated surface dependent term, which causes a quantum surface tension. In a rectangular box filled by an ideal gas and separated by a movable wall into two parts, it is shown that a lateral force appears on the movable wall due to quantum surface tension

  10. Separation anxiety: Stress, tension and cytokinesis

    International Nuclear Information System (INIS)

    Mohan, Krithika; Iglesias, Pablo A.; Robinson, Douglas N.

    2012-01-01

    Cytokinesis, the physical separation of a mother cell into two daughter cells, progresses through a series of well-defined changes in morphology. These changes involve distinct biochemical and mechanical processes. Here, we review the mechanical features of cells during cytokinesis, discussing both the material properties as well as sources of stresses, both active and passive, which lead to the observed changes in morphology. We also describe a mechanosensory feedback control system that regulates protein localization and shape progression during cytokinesis. -- Highlights: ► Cytokinesis progresses through three distinct mechanical phases. ► Cortical tension initially resists deformation of mother cell. ► Late in cytokinesis, cortical tension provides stress, enabling furrow ingression. ► A mechanosensory feedback control system regulates cytokinesis.

  11. Tension Tests On Bored Piles In Sand

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Clausen, Johan; Damkilde, Lars

    2006-01-01

    The lengths of the bored piles varied from 2 m to 6 m and all were of a diameter of 140 mm. The piles were tested to failure in tension and the load-displacement relations were recorded. The investigation has shown pronounced differences between the load bearing capacities obtained by different...... design methods. The methods proposed by Fleming et al. and Reese & O’Neill seem to produce the best match with the test results....

  12. Surface tension confined liquid cryogen cooler

    Science.gov (United States)

    Castles, Stephen H. (Inventor); Schein, Michael E. (Inventor)

    1989-01-01

    A cryogenic cooler is provided for use in craft such as launch, orbital, and space vehicles subject to substantial vibration, changes in orientation, and weightlessness. The cooler contains a small pore, large free volume, low density material to restrain a cryogen through surface tension effects during launch and zero-g operations and maintains instrumentation within the temperature range of 10 to 140 K. The cooler operation is completely passive, with no inherent vibration or power requirements.

  13. Surface tension of H2O and D2O

    International Nuclear Information System (INIS)

    Vargaftik, N.B.; Voljak, L.D.; Volkov, B.N.

    1975-01-01

    There is a great number of works on surface tension of clean water (H 2 O) at temperatures up to 100 deg C and very few above the boiling point. Works on surface tension of heavy water (D 2 O) are insufficient. A review of works on surface tension of both kinds of water is given

  14. Bilateral tension pneumothorax related to acupuncture.

    Science.gov (United States)

    Tagami, Rumi; Moriya, Takashi; Kinoshita, Kosaku; Tanjoh, Katsuhisa

    2013-06-01

    We report on a patient with a rare case of bilateral tension pneumothorax that occurred after acupuncture. A 69-year-old large-bodied man, who otherwise had no risk factors for spontaneous pneumothorax, presented with chest pressure, cold sweats and shortness of breath. Immediately after bilateral pneumothorax had been identified on a chest radiograph in the emergency room, his blood pressure and percutaneous oxygen saturation suddenly decreased to 78 mm Hg and 86%, respectively. We confirmed deterioration in his cardiopulmonary status and diagnosed bilateral tension pneumothorax. We punctured his chest bilaterally and inserted chest tubes for drainage. His vital signs promptly recovered. After the bilateral puncture and drainage, we learnt that he had been treated with acupuncture on his upper back. We finally diagnosed a bilateral tension pneumothorax based on the symptoms that appeared 8 h after the acupuncture. Because the patient had no risk factors for spontaneous pneumothorax, no alternative diagnosis was proposed. We recommend that patients receiving acupuncture around the chest wall must be adequately informed of the possibility of complications and expected symptoms, as a definitive diagnosis can be difficult without complete information.

  15. Tension-induced binding of semiflexible biopolymers

    International Nuclear Information System (INIS)

    Benetatos, Panayotis; Heydt, Alice von der; Zippelius, Annette

    2014-01-01

    We investigate theoretically the effect of polymer tension on the collective behavior of reversibly binding cross-links. For this purpose, we employ a model of two weakly bending wormlike chains aligned in parallel by a tensile force, with a sequence of inter-chain binding sites regularly spaced along the contours. Reversible cross-links attach and detach at the sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and find the emergence of a free-energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the tension increases. We show that this transition is related to the cross-over between weak and strong localization of a directed polymer in a pinning potential. The cross-over to the strongly bound state can be interpreted as a mechanism for force-stiffening which exceeds the capabilities of single-chain elasticity and thus available only to reversibly cross-linked polymers. (paper)

  16. Generalized surface tension bounds in vacuum decay

    Science.gov (United States)

    Masoumi, Ali; Paban, Sonia; Weinberg, Erick J.

    2018-02-01

    Coleman and De Luccia (CDL) showed that gravitational effects can prevent the decay by bubble nucleation of a Minkowski or AdS false vacuum. In their thin-wall approximation this happens whenever the surface tension in the bubble wall exceeds an upper bound proportional to the difference of the square roots of the true and false vacuum energy densities. Recently it was shown that there is another type of thin-wall regime that differs from that of CDL in that the radius of curvature grows substantially as one moves through the wall. Not only does the CDL derivation of the bound fail in this case, but also its very formulation becomes ambiguous because the surface tension is not well defined. We propose a definition of the surface tension and show that it obeys a bound similar in form to that of the CDL case. We then show that both thin-wall bounds are special cases of a more general bound that is satisfied for all bounce solutions with Minkowski or AdS false vacua. We discuss the limit where the parameters of the theory attain critical values and the bound is saturated. The bounce solution then disappears and a static planar domain wall solution appears in its stead. The scalar field potential then is of the form expected in supergravity, but this is only guaranteed along the trajectory in field space traced out by the bounce.

  17. Tension-induced binding of semiflexible biopolymers

    Science.gov (United States)

    Benetatos, Panayotis; von der Heydt, Alice; Zippelius, Annette

    2015-03-01

    We investigate theoretically the effect of polymer tension on the collective behaviour of reversible cross-links. We use a model of two parallel-aligned, weakly-bending wormlike chains with a regularly spaced sequence of binding sites subjected to a tensile force. Reversible cross-links attach and detach at the binding sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and we show the emergence of a free energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the polymer tension increases. The force-induced first-order transition in the number of cross-links implies a sudden force-induced stiffening of the effective stretching modulus of the polymers. This mechanism may be relevant to the formation and stress-induced strengthening of stress fibers in the cytoskeleton. We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) via grant SFB-937/A1.

  18. Detection of low tension cosmic superstrings

    Science.gov (United States)

    Chernoff, David F.; Tye, S.-H. Henry

    2018-05-01

    Cosmic superstrings of string theory differ from conventional cosmic strings of field theory. We review how the physical and cosmological properties of the macroscopic string loops influence experimental searches for these relics from the epoch of inflation. The universe's average density of cosmic superstrings can easily exceed that of conventional cosmic strings having the same tension by two or more orders of magnitude. The cosmological behavior of the remnant superstring loops is qualitatively distinct because the string tension is exponentially smaller than the string scale in flux compactifications in string theory. Low tension superstring loops live longer, experience less recoil (rocket effect from the emission of gravitational radiation) and tend to cluster like dark matter in galaxies. Clustering enhances the string loop density with respect to the cosmological average in collapsed structures in the universe. The enhancement at the Sun's position is ~ 105. We develop a model encapsulating the leading order string theory effects, the current understanding of the string network loop production and the influence of cosmological structure formation suitable for forecasting the detection of superstring loops via optical microlensing, gravitational wave bursts and fast radio bursts. We evaluate the detection rate of bursts from cusps and kinks by LIGO- and LISA-like experiments. Clustering dominates rates for G μ 10‑14.2 (LIGO cusp), G μ>10‑15 (LISA cusp) and G μ>10‑ 14.1 (LISA kink).

  19. Speaker and Observer Perceptions of Physical Tension during Stuttering.

    Science.gov (United States)

    Tichenor, Seth; Leslie, Paula; Shaiman, Susan; Yaruss, J Scott

    2017-01-01

    Speech-language pathologists routinely assess physical tension during evaluation of those who stutter. If speakers experience tension that is not visible to clinicians, then judgments of severity may be inaccurate. This study addressed this potential discrepancy by comparing judgments of tension by people who stutter and expert clinicians to determine if clinicians could accurately identify the speakers' experience of physical tension. Ten adults who stutter were audio-video recorded in two speaking samples. Two board-certified specialists in fluency evaluated the samples using the Stuttering Severity Instrument-4 and a checklist adapted for this study. Speakers rated their tension using the same forms, and then discussed their experiences in a qualitative interview so that themes related to physical tension could be identified. The degree of tension reported by speakers was higher than that observed by specialists. Tension in parts of the body that were less visible to the observer (chest, abdomen, throat) was reported more by speakers than by specialists. The thematic analysis revealed that speakers' experience of tension changes over time and that these changes may be related to speakers' acceptance of stuttering. The lack of agreement between speaker and specialist perceptions of tension suggests that using self-reports is a necessary component for supporting the accurate diagnosis of tension in stuttering. © 2018 S. Karger AG, Basel.

  20. Structural design significance of tension-tension fatigue data on composites

    Science.gov (United States)

    Grimes, G. C.

    1977-01-01

    Constant cycle tension-tension fatigue and related static tension data have been generated on six single composite material/orientation combinations and twenty-one hybrid composite material/orientation combinations. Anomalies are related to the temperature rise and stopped interval creep, whereas endurance limit stresses (runouts) are associated with static proportional limit values, when they occur, and internal damage. The significance of these room temperature-dry data on the design allowables and weight of aerodynamic structueres is discussed. Such structures are helicopter rotor blades and wing and horizontal stabilizer lower surfaces. Typical criteria for turning these data into preliminary allowables are shown, as are examples of such allowables developed from the data. These values are then compared to those that might be used if the structures were made of metal.

  1. Condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México

    Directory of Open Access Journals (Sweden)

    PRUDENCIA CERÓN-MIRELES

    1997-01-01

    Full Text Available Objetivo. Estudiar la asociación entre condiciones de trabajo materno y bajo peso al nacer en la Ciudad de México. Material y métodos. Se encuestaron 2 623 trabajadoras que atendieron sus partos en tres grandes hospitales de la Ciudad de México en 1992. Se obtuvo información sobre los principales factores biológicos y sociales que se asocian al bajo peso al nacer; asimismo, se determinó el estrés ocupacional utilizando el instrumento desarrollado por Karasek. Se utilizaron modelos de regresión logística para evaluar la relación de las condiciones de trabajo con el bajo peso al nacer, controlando por variables confusoras. Resultados. El bajo peso al nacer fue más alto en trabajadoras con jornadas mayores a 50 horas semanales (RM= 1.6; IC= 1.17, 2.28 y con conflictos laborales (RM= 1.5; IC= 1.0, 2.25. La falta de apoyo social tangible fue identificado como un factor de riesgo de bajo peso al nacer (RM= 1.7; IC= 1.20, 2.33. Las medidas preventivas laborales como el cambio de tareas, disminución de la jornada y las salidas por enfermedad no mostraron un efecto benéfico en el peso al nacer, a excepción de la licencia de maternidad; las madres que no la tuvieron mostraron una probabilidad 2.2 veces mayor para bajo peso al nacer (IC= 1.66, 2.93. Conclusiones. Estos hallazgos resaltan la importancia de identificar los factores de riesgo ocupacional en el embarazo..Objective. To study the association between maternal working conditions and low birth-weight in Mexico City. Material and methods. Interviews of 2 623 workers who gave birth in Mexico City hospitals during 1992 were analyzed. Information on the main biologic and social factors associated to low birth-weight was registered. Occupational stress was determined with the instrument designed by Karasek. Logistic regression models to evaluate the relationship between working conditions and low birth-weight were used, controlling by confounding variables. Results. Low birth-weight was

  2. Usos del celular en jóvenes chilenos de bajos recursos

    OpenAIRE

    Margarita Pedreros-Gajardo; Luis Araya-Castillo

    2013-01-01

    En este trabajo analizamos los significados que los jóvenes y las jóvenes de Chile de bajos recursos atribuyen a la compra, uso y tenencia de un celular. La investigación cualitativa utilizada no sólo nos permitió descubrir las necesidades que los sujetos jóvenes buscan satisfacer con la compra y/o uso de un celular, sino también los factores socioculturales que determinan este comportamiento de compra. La importancia del presente no es sólo por la pretensión de ser un estudio sociológico sob...

  3. Bluetooth 4.0 Low Energy: la futura solucion inalambrica de bajo consumo

    OpenAIRE

    Morales Pedro, Ricard

    2011-01-01

    En los últimos años el sector de las telecomunicaciones se ha erigido como uno de los mas innovadores de nuestra sociedad, donde la irrupción de nuevos estandares de comunicación inalambrica esta permitiendo ir eliminando la necesidad de los cables de transmisión para conectar dispositivos. Con este proposito nació Bluetooth, una tecnologia que permite transmisiones inalambricas de corto alcance de forma robusta y sencilla, junto con un consumo reducido y un bajo coste. Tras la aparición de B...

  4. Sobre un modelo de Holthausen para la empresa competitiva bajo incertidumbre en el precio

    OpenAIRE

    Álvarez López, A. A.

    1999-01-01

    El modelo presentado por HOLTHAUSEN (1979) amplía el modelo original de SANDMO (1971) para una empresa competitiva bajo incertidumbre en el precio y aversión al riesgo. La aportación esencial de HOLTHAUSEN es la de considerar que existe un mercado de futuros para el bien que la empresa produce, lo que causa que el comportamiento de ésta frente al riesgo sea diferente. En este trabajo planteamos el problema de decisión de la empresa del modelo de HOLTHAUSEN como un problema de optimización de ...

  5. Efectos del bajo peso materno preconcepcional sobre el embarazo y el parto

    OpenAIRE

    López Montero, Maribel; Trufero Cánovas, Norma

    2006-01-01

    Se realizó un estudio de cohorte no concurrente pareado 1:1 para investigar los efectos del bajo peso materno preconcepcional (malnutrición materna por defecto) sobre el embarazo, el parto y el recién nacido en el Policlínico Finlay del municipio Camagüey desde octubre de 2002 hasta abril de 2004. Fueron estudiadas 51 gestantes malnutridas por defecto y 51 embarazadas sin riesgo. Los datos fueron tomados a partir de los registros oficiales de la atención perinatal complementados con una encue...

  6. Alumnos con Bajo Rendimiento Escolar, los blogs y el tutor de Primaria

    OpenAIRE

    Rico-Sánchez, Jesús David

    2013-01-01

    Teniendo en cuenta el problema que tiene el sistema educativo español con un índice muy elevado de fracaso escolar, se pretendió investigar concretamente sobre los alumnos del sexto curso de Primaria que presentan Bajo Rendimiento Escolar aprovechando los avances tecnológicos existentes en la actualidad y que han penetrado con gran fuerza en la sociedad. Por ello, el problema planteado en este trabajo es estudiar si el potencial motivador, comunicativo y utilitario del Edublog puede ayudar a ...

  7. La identificación de espacios mineros e industriales abandonados: el caso del Bajo Besaya

    OpenAIRE

    García Valiente, Nieves; Nogués Linares, Soledad

    2014-01-01

    La recuperación de los terrenos conocidos como “brownfields” es un tema recurrente en las políticas del suelo y el medio ambiente de la Unión Europea para el horizonte 2020. Con una tradición eminentemente industrial y minera, el Bajo Besaya presenta, en la actualidad, amplios espacios abandonados degradados, que son el resultado del cese de las actividades productivas anteriores. Éstos suponen un detrimento para la zona, por lo que es necesaria su transformación de pasivos ambientales y soci...

  8. Análisis del bajo peso en la atención primaria

    Directory of Open Access Journals (Sweden)

    Miguel Lugones Botell

    1995-08-01

    Full Text Available Se realiza un estudio retrospectivo de algunos aspectos relacionados con la atención prenatal de las gestantes y su análisis correspondiente, que tuvieron recién nacidos de bajo peso en el período comprendido entre 1988 y 1991, ambos inclusive. Se concluye que los principales factores relacionados con éste fueron: nuliparidad, madre trabajadora, poca ganancia de peso en el embarazo y entre las afecciones asociadas con la gestación encontramos la amenaza de aborto, la anemia y la enfermedad hipertensiva del embarazo, entre las más frecuentes.

  9. Análisis del amortiguamiento en vidrio estructural bajo cargas de impacto

    OpenAIRE

    Ramos, Alberto; Pelayo, F.; Lamela, María Jesús; Fernández Canteli, Alfonso; Huerta Gómez de Merodio, María Consuelo; Pacios Alvarez, Antonia

    2013-01-01

    Los últimos avances tecnológicos y las tendencias arquitectónicas actuales han impulsado notablemente el uso de una gran variedad de productos de vidrio en la construcción que, en función de sus propias características, permiten diseñar y calcular elementos estructurales de este material bajo condiciones de seguridad. Este trabajo presenta la evaluación y el análisis de las propiedades de amortiguamiento de placas rectangulares de vidrio laminado de 1938 mm x 876 mm con distinto espesor, segú...

  10. Corrosión microbiológica en aceros de bajo carbono

    OpenAIRE

    Medina-Custodio, O; Ortiz-Prado, A; Jacobo-Armendáriz, V.H.; Schouwenaars-Franssens, R

    2009-01-01

    La corrosión microbiológica es un tipo común de deterioro que afecta diversas industrias, una de ellas es la petrolera en la que se estiman que el 20% o 30% de fallas en las tuberías de trasporte de hidrocarburos es favorecida por microorganismos. Las reacciones químicas que sustentan éstos, generan transferencia de iones, lo que justifica el empleo de técnicas electroquímicas para su análisis. En este trabajo, se estudiaron probetas de acero de bajo carbono SAE 1018, sumergidas en un medio n...

  11. Involucramiento parental escolar en alumnos de bachillerato de alto y bajo rendimiento

    OpenAIRE

    Ortega Pierres, Susana; Andrade, Patricia; Vásquez Olmedo, Claudia Elena

    2016-01-01

    El Sistema Educativo Mexicano enfrenta problemas como bajo desempeño y reprobación, circunstancias que anteceden el abandono escolar, el cual se ubica como un fenómeno multicausal, en el que además de los diversos factores relacionados (personales, familiares, escolares, económicos sociales, etc.) se caracteriza por una tendencia a incrementarse conforme los alumnos avanzan en la escuela. De 100 alumnos que ingresan a primaria, 24 concluyen el nivel medio superior y de estos solo 14 concluyen...

  12. Evaluación de un cluster bajo agricultura protegida en México

    OpenAIRE

    Padilla-Bernal, Luz Evelia; Reyes-Rivas, Eliver; Pérez-Veyna, Óscar

    2012-01-01

    El naciente cluster de tomate bajo agricultura protegida en Zacatecas enfrenta el reto de participar en los mercados globales de una manera sostenible; una respuesta viable para ello es elevar su capacidad de upgrading. En este trabajo se determina la relación entre la eficiencia colectiva en el upgrading del cluster. La información se obtuvo a través de un cuestionario aplicado a técnicos de las unidades de producción (UP), el cual se complementó con entrevistas a propietarios o gerentes, in...

  13. La importancia de los materiales en las viviendas de muy bajo coste

    OpenAIRE

    Salas, Julián

    1992-01-01

    El texto que sigue se encuadra en el contexto de intentar enmarcar la importancia considerable del capítulo de los materiales de construcción en el subsector de las viviendas de muy bajo coste en los Países en Vías de Desarrollo en general, y en Latinoamérica en particular. El autor trata de cuantificar, en forma global, la repercusión de los materiales en varios supuestos y como ésta aumenta al disminuir —prácticamente desaparecer— las partidas de instalaciones y acabados. De conformidad...

  14. Cuerpo y subjetividad: materiales y tensiones

    OpenAIRE

    Cachorro, Gabriel

    2007-01-01

    En este artículo se efectúa un abordaje del tema cuerpo y subjetividad a través de un ejercicio exploratorio de sus materiales y tensiones. Las preguntas posibles de formular son: ¿Qué discusiones tenemos por debajo de la subjetividad corporal?, ¿cuáles son las raíces históricas de este tema?, ¿qué problemáticas lo atraviesan? La enunciación de estos interrogantes nos ayuda a establecer la posición de investigador y a explicitar los argumentos teóricos. Se desprende de esta propuest...

  15. Temporomandibular disorders and tension-type headache.

    Science.gov (United States)

    Mongini, Franco

    2007-12-01

    Pathologies currently defined as temporomandibular disorders may be different in nature. Temporomandibular joint (TMJ) disorders and craniofacial and cervical myogenous pain (MP) are distinct pathologies but may be superimposed and share some etiologic factors. Tension-type headache (TTH) may often be associated with craniofacial and cervical pain, and the same pharmacologic and nonpharmacologic treatment may be efficacious for both. Psychiatric comorbidity (depression and/or anxiety disorder) is less frequent in sheer TMJ disorders, compared with MP and TTH. A screening for the presence of an underlying psychiatric disorder should be part of the clinical evaluation in patients suffering from headache and facial pain.

  16. Small-Bolt Torque-Tension Tester

    Science.gov (United States)

    Posey, Alan J.

    2009-01-01

    The device described here measures the torque-tension relationship for fasteners as small as #0. The small-bolt tester consists of a plate of high-strength steel into which three miniature load cells are recessed. The depth of the recess is sized so that the three load cells can be shimmed, the optimum height depending upon the test hardware. The three miniature load cells are arranged in an equilateral triangular configuration with the test bolt aligned with the centroid of the three. This is a kinematic arrangement.

  17. Superficial tension: experimental model with simple materials

    Directory of Open Access Journals (Sweden)

    Tintori Ferreira, María Alejandra

    2012-09-01

    Full Text Available In this work appears a didactic offer based on an experimental activity using materials of very low cost, orientated to achieving that the student understand and interpret the phenomenon of superficial tension together with the importance of the modeling in sciences. It has as principal aim of education bring the student over to the mechanics of the static fluids and the intermolecular forces, combining scientific contents with questions near to the student what provides an additional motivation to the reflection of the scientific investigation.

  18. Effective tension and fluctuations in active membranes

    OpenAIRE

    Loubet, Bastien; Seifert, Udo; Lomholt, Michael Andersen

    2011-01-01

    We calculate the fluctuation spectrum of the shape of a lipid vesicle or cell exposed to a nonthermal source of noise. In particular we take into account constraints on the membrane area and the volume of fluid that it encapsulates when obtaining expressions for the dependency of the membrane tension on the noise. We then investigate three possible origins of the non-thermal noise taken from the literature: A direct force, which models an external medium pushing on the membrane. A curvature f...

  19. Comparison of acceptor properties for interaction of TCNE and DDQ ...

    African Journals Online (AJOL)

    ... with tetracyanoethylene and 2,3-dichloro-5,6-dicyanobezoquinone as acceptors result in charge-transfer adducts of composition 2:1 of acceptor to donor, [(acceptor)2(donor)]. Formation constants, K, as well as the thermodynamic parameters, ΔH°, ΔS°, and ΔG° were determined by UV-Vis titration method for the adducts.

  20. A polarized view on DNA under tension

    Science.gov (United States)

    van Mameren, Joost; Vermeulen, Karen; Wuite, Gijs J. L.; Peterman, Erwin J. G.

    2018-03-01

    In the past decades, sensitive fluorescence microscopy techniques have contributed significantly to our understanding of the dynamics of DNA. The specific labeling of DNA using intercalating dyes has allowed for quantitative measurement of the thermal fluctuations the polymers undergo. On the other hand, recent advances in single-molecule manipulation techniques have unraveled the mechanical and elastic properties of this intricate polymer. Here, we have combined these two approaches to study the conformational dynamics of DNA under a wide range of tensions. Using polarized fluorescence microscopy in conjunction with optical-tweezers-based manipulation of YOYO-intercalated DNA, we controllably align the YOYO dyes using DNA tension, enabling us to disentangle the rapid dynamics of the dyes from that of the DNA itself. With unprecedented control of the DNA alignment, we resolve an inconsistency in reports about the tilted orientation of intercalated dyes. We find that intercalated dyes are on average oriented perpendicular to the long axis of the DNA, yet undergo fast dynamics on the time scale of absorption and fluorescence emission. In the overstretching transition of double-stranded DNA, we do not observe changes in orientation or orientational dynamics of the dyes. Only beyond the overstretching transition, a considerable depolarization is observed, presumably caused by an average tilting of the DNA base pairs. Our combined approach thus contributes to the elucidation of unique features of the molecular dynamics of DNA.

  1. Shape accuracy optimization for cable-rib tension deployable antenna structure with tensioned cables

    Science.gov (United States)

    Liu, Ruiwei; Guo, Hongwei; Liu, Rongqiang; Wang, Hongxiang; Tang, Dewei; Song, Xiaoke

    2017-11-01

    Shape accuracy is of substantial importance in deployable structures as the demand for large-scale deployable structures in various fields, especially in aerospace engineering, increases. The main purpose of this paper is to present a shape accuracy optimization method to find the optimal pretensions for the desired shape of cable-rib tension deployable antenna structure with tensioned cables. First, an analysis model of the deployable structure is established by using finite element method. In this model, geometrical nonlinearity is considered for the cable element and beam element. Flexible deformations of the deployable structure under the action of cable network and tensioned cables are subsequently analyzed separately. Moreover, the influence of pretension of tensioned cables on natural frequencies is studied. Based on the results, a genetic algorithm is used to find a set of reasonable pretension and thus minimize structural deformation under the first natural frequency constraint. Finally, numerical simulations are presented to analyze the deployable structure under two kinds of constraints. Results show that the shape accuracy and natural frequencies of deployable structure can be effectively improved by pretension optimization.

  2. Materiales, tecnologías y prototipos de viviendas de muy bajo coste

    Directory of Open Access Journals (Sweden)

    Salas Serrano, Julián

    1982-11-01

    Full Text Available Not available.El fin último de la investigación es el de conseguir unas tipologías de viviendas realizadas mediante materiales, procedimientos o sistemas constructivos que permitan proporcionar un producto final, cuyas características fundamentales sean: adecuación a las necesidades físicas y socioculturales de la zona y, prioritariamente, la consecución de un muy bajo coste da ejecución de las mismas. Cuando se habla a continuación de «viviendas de muy bajo coste» se debe entender que nos referimos a las que cumplen básicamente las dos condiciones limitativas aceptadas por las Naciones Unidas (UNCHSHABITAT: a Superficie construida comprendida entre 30 y 50 m2. b Coste de construcción inferior a los 100 $ USA (1982 por metro cuadrado construido. (Para nuestras condiciones, fijaríamos un coste aproximado de 10.000 pts/m2.

  3. Algunas variables bioquímicas en adolescentes obesos con antecedente de bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    María del Carmen Valdés Alonso

    Full Text Available Introducción: la malnutrición intraútero ha sido postulada con vinculación a afecciones del desarrollo embrionario que determinan el desarrollo ulterior de obesidad, diabetes mellitus tipo 2, dislipidemias, disfunción mitocondrial y aterosclerosis. Objetivo: determinar las complicaciones metabólicas en adolescentes obesos con antecedentes de bajo peso al nacer. Métodos: estudio descriptivo y de corte transversal. Se incluyeron 50 pacientes obesos, con antecedentes de bajo peso al nacer y embarazo a término, de ambos sexos, en las edades comprendidas entre 9 y 17 años de edad, que asistieron a la consulta externa del servicio de Endocrinología del Hospital Pediátrico Docente "Juan Manuel Márquez", en el período comprendido de enero de 2011 a enero de 2012. Se realizaron determinaciones de colesterol, triglicéridos, aminotransferasas hepáticas, glucemia, e insulinemia en ayunas y posprandial de dos horas. Resultados: las variables bioquímicas estudiadas no mostraron diferencias entre los puntos de corte utilizados para clasificar el peso al nacer. La transaminasa glutámico pirúvica mostró valores más altos en los adolescentes entre 15 y 17 años de edad. Conclusiones: la hipertrigliceridemia fue más elevada en el sexo femenino, mientras que la hiperglucemia y la hiperinsulinemia lo fueron en el masculino.

  4. Glosa paseada bajo el fuego y la lluvia: cinco lentes para mirar el Chocó

    Directory of Open Access Journals (Sweden)

    Mónica María del Valle Idárraga

    2011-12-01

    Full Text Available A partir de la perspectiva general de la ecocrítica o ecopoética, este artículo analiza los modos como se representa la naturaleza y su relación con lo humano en la obra Glosa paseada bajo el fuego y la lluvia (1982 del escritor chocoano Carlos Arturo Caicedo Licona. Las cinco instancias de esa figuración que aquí se estudian ayudan a crear un universo simbólico que respalda una idea de chocoanidad cifrada en prácticas, creencias, recorridos y visiones desde un marco anterior a tecnologías de la identidad como la biodiversidad o la patrimonialización.Based on the general premises of Ecocriticism, this article explores the ways in which nature and its inter-relation to human beings is created in Glosa paseada bajo el fuego y la lluvia, a work by Carlos Arturo Caicedo Licona, a writer from Chocó, Colombia. Five instances of that representation are analyzed as pieces that, while describing practices, conceptions, beliefs and cartographic descriptions, structure an idea of Chocoan identity previous to current identity technologies, such as patrimonialization and biodiversity.

  5. THE CONSTRUCTION AND CONTESTATION OF ISLAMIC IDENTITY OF THE BAJO PEOPLE IN WAKATOBI ISLANDS, SOUTH EAST SULAWESI, INDONESIA

    Directory of Open Access Journals (Sweden)

    Benny Baskara

    2014-02-01

    Full Text Available On the one one hand, the Bajo people are well-known as ‘the sea people’ who have their own indigenous belief system – belief in the Lord of the Sea. On the other hand, they also acknowledge themselves as Muslims. Thus, the religious identity of the Bajo people reflects a unique combination of Islamic teachings and their indigenous beliefs. This unique combination is not only expressed in their religious life, in their rituals and worship practices, but also in the values found in their customary practices (adat as a guiding system for their life. This paper examines the construction and contestation of the religious identity of the Bajo people, especially how they construct their identities in relation to their natural, social, and religious environments. The contestation of the Bajo religious identity covers three aspects: the contestation of the Islam of ‘the sea people’ against the Islam of ‘the land people’, the contenstation of the ‘official’ Islam against the ‘traditional’ Islam, and the challenges of modernity, especially the commodification of the Bajo religious expressions. This contestation, in turn, reconstructs their religious identity into a more adaptive one.

  6. The tension of framed membranes from computer simulations

    DEFF Research Database (Denmark)

    Hamkens, Daniel; Jeppesen, Claus; Ipsen, John H.

    2018-01-01

    the membranes display power-law characteristics for the equation of state, while higher tension levels includes both an extended linear (elastic) as well as a highly non-linear stretching regime. For semi-flexible membranes a transition from extended to buckled conformations takes place at negative frame......Abstract.: We have analyzed the behavior of a randomly triangulated, self-avoiding surface model of a flexible, fluid membrane subject to a circular boundary by Wang-Landau Monte Carlo computer simulation techniques. The dependence of the canonical free energy and frame tension on the frame area...... is obtained for flexible membranes. It is shown that for low bending rigidities the framed membrane is only stable above a threshold tension, suggesting a discontinuous transition from the collapsed (branched polymer) state to a finite tension extended state. In a tension range above this threshold tension...

  7. A simple method for the design of tension structures combining topological mapping and nonlinear structural analysis

    Directory of Open Access Journals (Sweden)

    Jurado-Piña, R.

    2014-12-01

    Full Text Available When designing a tension structure the shape is not known at the beginning of the process. Form-finding methods allow the designer to obtain an initial shape from given boundary conditions. Several form-finding methods for tension structures are already available in the technical literature; all of them posses certain limitations and drawbacks and no single method is optimal for all problems. The engineer may select the proper combination of methods best suited to the designer’s needs. In this paper it is proposed a combined method to achieve satisfactory equilibrium configurations for fabric tension structures. The force density method (FDM implemented with topological mapping (TM is used as a search engine for the preliminary design, and a procedure that employs nonlinear structural analysis is proposed for final refinement of the initial equilibrium configuration hence allowing the use of the same analysis tool for both refinement of the solution and analysis under loading.Al diseñar una estructura tensada la forma inicial es normalmente desconocida. Los métodos de búsqueda de forma permiten al ingeniero obtener una geometría inicial dadas unas condiciones de contorno. Existen diferentes métodos de búsqueda de formas de equilibrio, pero todos tienen limitaciones y no existe uno único óptimo para cualquier tipo de problema. El ingeniero debe elegir la combinación de métodos que mejor se adapte a sus necesidades. En este artículo se propone un método combinado para generar configuraciones de equilibrio satisfactorias en estructuras tensadas. Como motor de búsqueda para el diseño preliminar se emplea el método de las densidades de fuerza (FDM implementado con mallado en topología (TM, y se propone un procedimiento basado en análisis no lineal de estructuras para el refinamiento de la configuración inicial de equilibrio, permitiéndose así el empleo de las mismas herramientas tanto para el refinamiento de la solución inicial

  8. Surface tension of liquid Al-Cu binary alloys.

    OpenAIRE

    Schmitz, Julianna; Brillo, Jürgen; Egry, Ivan; Schmid-Fetzer, Rainer

    2009-01-01

    Surface tension data of liquid Al–Cu binary alloys have been measured contactlessly using the technique of electromagnetic levitation. A digital CMOS-camera (400 fps) recorded image sequences of the oscillating liquid sample and surface tensions were determined from analysis of the frequency spectra. Measurements were performed for samples covering the entire range of composition and precise data were obtained in a broad temperature range. It was found that the surface tensions can ...

  9. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2006-01-01

    A special Bending-Under-Tension (BUT) transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all...... measured directly, thus enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication...

  10. The law of corresponding states and surface tension of metals

    International Nuclear Information System (INIS)

    Digilov, R.

    2001-01-01

    Full Text: Surface tension of liquid metals is one of fundamental and most important quantities in theory and practice of material processing and its temperature dependence leads to the well-known Marangoni convection. Although currently methods are sufficiently precise to measure the surface tension, there are uncertainties in experimental data and its temperature dependence mainly due to impurity, which even a trace of it strongly affects the results of measurements. The theoretical treatment from the first principles is unwieldy and not always permits one to calculate the surface tension with certainty. Another active research field deals with empirical correlation between the surface tension and bulk thermodynamic properties, which we interpret as a simple consequence of the law of corresponding states. In order to relate the surface tension and to bulk properties of liquid metals the reduced formula is derived by scaling with the melting point T m (0) at p = 0 and atomic volume Ω 0 2/3 at T = 0 K as macroscopic parameters for scaling ε and a characterizing the interatomic potential in metals. The reduced surface tension and the reduced surface entropy obtained in high temperature limit are discussed and compared with the experiment. The reduced temperature coefficient of the surface tension found is a universal constant for the metals of the same structure. It is shown that pressure dependence of the surface tension, so called baric coefficient of the surface tension, can be described by pressure dependence of scaling parameters T m (p) and Ω 0 (p). (author)

  11. Strain Capacity of Reinforced Concrete Members Subjected to Uniaxial Tension

    DEFF Research Database (Denmark)

    Hagsten, Lars German; Rasmussen, Annette Beedholm; Fisker, Jakob

    2017-01-01

    The aim of this paper is to set up a method to determine the strain capacity of tension bars of reinforced concrete (RC) subjected to pure tension. Due to the interaction between reinforcement and concrete and due to the presence of cracks, the stresses in both reinforcement and concrete...... are varying along the length of the tension bar. The strain capacity of the tension bar is seen as the average strain in the reinforcement at the load level corresponding to the ultimate stress capacity of the reinforcement at the cracks. The result of the approach is in overall good agreement when comparing...

  12. An automatic tension measurement system of MWPC wires

    International Nuclear Information System (INIS)

    D'Antone, I.; Lolli, M.; Torromeo, G.

    1992-01-01

    An electronic system is presented for automatic mechanical tension measurement to test wire chambers. The developed system works in the tension range from 50 g to 300 g; this large working range is obtained by using a microcontroller that performs a digital control on the bridge of an oscillator containing the wire of which the tension has to be measured. The microcontroller automatically brings the system towards the oscillation condition and subsequently, measuring the frequency, it evaluates, displays and sends to a host computer the value of the mechanical tension of the wires. The system is precise and allows fast measurements. A description of the hardware and software design is given. (orig.)

  13. Autoestima en adolescentes con bajo rendimiento escolar a través del psicodiagnóstico de Rorschach

    Directory of Open Access Journals (Sweden)

    Magally de Garrido-Lecca

    1997-12-01

    Full Text Available El objetivo fue determinar si existen diferencias en la autoestima de adolescentes con bajo rendimiento escolar comparados con los de un rendimiento promedio o superior. Los participantes fueron 60 adolescentes, entre 13 y 16 años, de ambos sexos, con un C.I. promedio o superior al promedio, de los cuales 30 presentaban un bajo rendimiento escolar  (grupo de estudio y 30 un buen rendimiento (grupo contraste. Se administró el WISCR para determinar el C.I. y el Rorschach según el SC de Exner para evaluar la autoestima. Los resultados mostraron que el Rorschach es adecuado para evaluar la autoestima. Asimismo existe una diferencia significativa en la autoestima de adolescentes con bajo rendimiento como resultado de sus déficits afectivos, en comparación con los de alto rendimiento.

  14. Cavitation propagation in water under tension

    Science.gov (United States)

    Noblin, Xavier; Yip Cheung Sang, Yann; Pellegrin, Mathieu; Materials and Complex Fluids Team

    2012-11-01

    Cavitation appears when pressure decreases below vapor pressure, generating vapor bubbles. It can be obtain in dynamical ways (acoustic, hydraulic) but also in quasi-static conditions. This later case is often observed in nature, in trees, or during the ejection of ferns spores. We study the cavitation bubbles nucleation dynamics and its propagation in a confined microfabricated media. This later is an ordered array of microcavities made in hydrogel filled with water. When the system is put into dry air, it dehydrates, water leaves the cavities and tension (negative pressure) builds in the cavities. This can be sustained up to a critical pressure (of order -20 MPa), then cavitation bubbles appear. We follow the dynamics using ultra high speed imaging. Events with several bubbles cavitating in a few microseconds could be observed along neighboring cells, showing a propagation phenomenon that we discuss. ANR CAVISOFT 2010-JCJC-0407 01.

  15. Tension Tests of Copper Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyung Jo; Kim, Chung Youb [Chonnam Nat’l Univ., Gwangju (Korea, Republic of)

    2017-08-15

    Tension tests for copper thin films with thickness of 12 μm were performed by using a digital image correlation method based on consecutive digital images. When calculating deformation using digital image correlation, a large deformation causes errors in the calculated result. In this study, the calculation procedure was improved to reduce the error, so that the full field deformation and the strain of the specimen could be accurately and directly measured on its surface. From the calculated result, it can be seen that the strain distribution is not uniform and its variation is severe, unlike the distribution in a common bulk specimen. This might result from the surface roughness introduced in the films during the fabrication process by electro-deposition.

  16. Tension Type Headache: Evaluation of Chronic Type

    Directory of Open Access Journals (Sweden)

    Ömer Karadaş

    2013-11-01

    Full Text Available Tension type headache(TTH which is a primary headache has episodic and chronic forms. Episodic TTH (ETTH can also be frequent-type and non-frequent-type. According to population-based studies, annual prevalence rates are 38.3% for ETTH and 2.2% for chronic TTH (CTTH. Patients can shift between the sub-groups of TTH. In particular, patients with ETTH are at risk of developing CTTH. Peripheral and central nociceptive mechanism are thought to be responsible in occurrence of TTH. Psychiatric disorders are frequently associated with TTH. Although basic and combined analgesics are used in acute treatment and antidepresants are used in prophylaxis, new treatment modalities are needed.

  17. Effective tension and fluctuations in active membranes.

    Science.gov (United States)

    Loubet, Bastien; Seifert, Udo; Lomholt, Michael Andersen

    2012-03-01

    We calculate the fluctuation spectrum of the shape of a lipid vesicle or cell exposed to a nonthermal source of noise. In particular, we take constraints on the membrane area and the volume of fluid that it encapsulates into account when obtaining expressions for the dependency of the membrane tension on the noise. We then investigate three possible origins of the nonthermal noise taken from the literature: A direct force, which models an external medium pushing on the membrane, a curvature force, which models a fluctuating spontaneous curvature, and a permeation force coming from an active transport of fluid through the membrane. For the direct force and curvature force cases, we compare our results to existing experiments on active membranes.

  18. Importancia de los antecedentes maternos en el recién nacido bajo peso

    Directory of Open Access Journals (Sweden)

    Gil Vicente Sarmiento Brooks

    2000-10-01

    Full Text Available Se realizó un estudio observacional, analítico, con un modelo de diseño del tipo casos y controles en 117 mujeres del Policlínico Docente "La Rampa" perteneciente al municipio Plaza de la Revolución de las cuales 17 tuvieron un recién nacido con un peso inferior a los 2 500 g. Las restantes 100 mujeres lograron niños con un peso igual al anteriormente señalado o superior. Analizamos la influencia de algunos antecedentes como el orden de nacimientos y de embarazos, el número de abortos y las gestaciones de bajo peso anteriores y determinados antecedentes patológicos de la madre. Se concluyó que los factores que influyen en el nacimiento de un niño con bajo peso son, entre otros: que sea el primer nacimiento (RR = 2; el primer embarazo (RR = 1,8; el haber tenido 2 o más abortos previos (RR = 4,9, el antecedente de haber tenido uno o más recién nacido de bajo peso (RNBP (RR = 6,9 y ciertas enfermedades maternas como la urosepsis (RR = 3,7, la hipertensión crónica (RR = 3,21, la anemia (RR = 2,7 y el asma (RR = 1,9. Se hacen algunas recomendacionesAn observational and analytical case-control study was conducted among 117 women attended at "La Rampa" Teaching Polyclinic, in the municipality of Plaza de la Revolución. 17 of these women had a newborn infant with a birth weight under 2 500 g. The rest of them had children with the same weight or higher. The influence of some history as the order of births and pregnancies, the number of abortions and the previous low weight gestations and certain pathological history of the mother were analyzed. It was concluded that the factors that influenced on the birth of a low birth weight infant are, among others: the first birth (RR=2, the first pregnancy (RR=1,8; having had 2 or more previous abortions (RR=4,9, having had one or more low birth weight infants (RR=6,9, and some maternal diseases as urosepsis (RR=3,7, chronic hypertension (RR=3,21, anemia (RR=2,7 and asthma (RR=1,9

  19. Modelación de tensiones de contacto originadas en la llanta del secador rotatorio de menas lateríticas

    Directory of Open Access Journals (Sweden)

    Edidiong Uboho

    2013-11-01

    Full Text Available El propósito de la investigación fue modelar el comportamiento de las tensiones de contacto de naturaleza compresiva y térmica que se originan en las llantas del horno de tambor rotatorio, con el fin de realizar ensayos de fatiga y desgaste superficial en las llantas. Primeramente se estableció un modelo teórico para estimar las tensiones en la llanta. Se discretizó, mediante el software ANSYS v.12.1, un modelo geométrico equivalente de la llanta y de la zona de contacto. Por último, mediante el método de elementos finitos, se simularon los contactos para estimar el comportamiento de las tensiones. Los resultados mostraron que la tensión máxima actúa sobre la línea media de la banda de contacto y su valor es directamente proporcional a la fuerza sobre la llanta y a su temperatura. El valor más elevado de tensión máxima de contacto (415,14 MPa se observó para 1 254 467 N de fuerza sobre la llanta y temperatura de 100 °C; mientras que el valor más bajo (87,662 MPa fue para 1 153 915 N y 40 °C.

  20. Situación General de la Industria de la Construcción de Bajo Bordo

    OpenAIRE

    Chui, Alexander; Gamero, Magali; Cornejo, Karla; Rios, Vanessa; Valdivia, Maria Laura; Benzaquén de las Casas, Jorge

    2016-01-01

    Objetivo: Determinar las condiciones en que se encuentra la industria de construcción naval de bajo bordo en el Perú, relacionado con su contexto latinoamericano. Métodos: Se estableció un protocolo de actuación a base entrevistas, cuestionarios y recopilación de datos con el fin de conocer los principales indicadores de la dinámica funcional e industria de construcción naval de bajo bordo. Resultados: El Perú ha crecido notablemente en las últimas dos décadas como consecuencia de la apertura...

  1. Comportamiento Tribológico de Aluminio Sinterizado y Desgastado Bajo Distintas Condiciones Comportamiento Tribológico de Aluminio Sinterizado y Desgastado Bajo Distintas Condiciones

    Directory of Open Access Journals (Sweden)

    Veridiana Reyes Z.

    2012-02-01

    Full Text Available Wear is one of the most costly damages in industry and research has been directed towards its prevention. This paper deals with the behavior of aluminum pieces, prepared by powder metallurgy, under wear. The samples tested were prepared under different processing conditions (compacting pressure, temperature and sintering time. The wear test was carried out ina pin-in-disc machine, at various rates and wear pressures. The results showed the tribological behavior of aluminum. Also, a comparative study between a 356-aluminium alloy and pure aluminum was carried out, showing the feasibility of attaining similar tribological behavior between a conventional alloy and pure aluminum prepared by powder metallurgy techniques.El desgaste es uno de los daños más costosos para la industria y las investigaciones buscan entender los mecanismos del desgaste que podrían disminuirlo o evitarlo. Este trabajo analiza el comportamiento del aluminio obtenido por metalurgia de polvos cuando se somete a desgaste. Las muestras usadas fueron preparadas bajo diversas condiciones de proceso (presión de la compactación, la temperatura y tiempode tratamiento térmico. Las pruebas de desgaste se realizaron en una máquina de pin-en-disco y fueron probados diferentes valores de velocidad y presión de desgaste. Los resultados obtenidos muestran el comportamiento tribológico del aluminio. Se presenta también un estudio comparativo entre una aleación de aluminio 356 y aluminio puro, demostrándose la viabilidad de lograr un comportamiento tribológico similar entre esta aleación convencional y el aluminio puro preparado por metalurgia de polvos.

  2. Membrane tension regulates clathrin-coated pit dynamics

    Science.gov (United States)

    Liu, Allen

    2014-03-01

    Intracellular organization depends on close communication between the extracellular environment and a network of cytoskeleton filaments. The interactions between cytoskeletal filaments and the plasma membrane lead to changes in membrane tension that in turns help regulate biological processes. Endocytosis is thought to be stimulated by low membrane tension and the removal of membrane increases membrane tension. While it is appreciated that the opposing effects of exocytosis and endocytosis have on keeping plasma membrane tension to a set point, it is not clear how membrane tension affects the dynamics of clathrin-coated pits (CCPs), the individual functional units of clathrin-mediated endocytosis. Furthermore, although it was recently shown that actin dynamics counteracts membrane tension during CCP formation, it is not clear what roles plasma membrane tension plays during CCP initiation. Based on the notion that plasma membrane tension is increased when the membrane area increases during cell spreading, we designed micro-patterned surfaces of different sizes to control the cell spreading sizes. Total internal reflection fluorescence microscopy of living cells and high content image analysis were used to quantify the dynamics of CCPs. We found that there is an increased proportion of CCPs with short (<20s) lifetime for cells on larger patterns. Interestingly, cells on larger patterns have higher CCP initiation density, an effect unexpected based on the conventional view of decreasing endocytosis with increasing membrane tension. Furthermore, by analyzing the intensity profiles of CCPs that were longer-lived, we found CCP intensity decreases with increasing cell size, indicating that the CCPs are smaller with increasing membrane tension. Finally, disruption of actin dynamics significantly increased the number of short-lived CCPs, but also decreased CCP initiation rate. Together, our study reveals new mechanistic insights into how plasma membrane tension regulates

  3. Damage development in woven fabric composites during tension-tension fatigue

    DEFF Research Database (Denmark)

    Hansen, U.

    1999-01-01

    of the operating fatigue damage mechanism(s). Fatigue leads to a degradation of material properties. Consequently, in connection with impact induced local stress raisers, fatigue produces continuously changing non-uniform stress fields because of stress redistribution effects. Other models addressing evolution...... of fatigue damage in composite materials have not been able to simulate evolving nonuniform stress fields. Therefore. in the second part of this paper, an analytical/numerical approach capable of addressing these issues is also proposed.......Impacted woven fabric composites were tested in tension-tension fatigue. In contrast to results from static testing, the effects of low energy impact damage in a fatigue environment were found to be the critical element leading to failure of the specimen. This difference emphasizes the need...

  4. Sobre la toma de decisiones económicas bajo incertidumbre

    Directory of Open Access Journals (Sweden)

    Aurora García Gallego

    2012-04-01

    Full Text Available En este artículo resumimos la evolución de la Teoría Económica sobre la toma de decisiones bajo incertidumbre. Tras una breve introducción a la teoría de la Utilidad Esperada, nos referimos a comportamientos paradójicos que obligaron a los economistas a adoptar teorías menos simplistas que permitieran explicar un mayor abanico de fenómenos. La mayor complejidad conlleva una descripción multidimensional de las actitudes humanas frente al riesgo económico. Sin embargo, las mediciones de la actitud frente al riesgo utilizadas por los economistas continúan siendo, en su mayoría, unidimensionales.

  5. Vernacular modernism and melodramatic imagination in Bajo el cielo antioqueño

    Directory of Open Access Journals (Sweden)

    Álvaro Andrés Villegas

    2016-12-01

    Full Text Available This article focuses on the film “Bajo el cielo antioqueño”, directed by Arturo Acevedo Vallarino and released in 1925. First, the collective efforts of the Medellin privileged sectors are described, which participated as investors and as actors. Then, the movie’s appropriation of what could be called the “vernacular modernism” is analyzed through the cultural matrix of melodrama, which is characterized by intensity and schematization of feelings, by the story’s development from ignorance to recognition, the supremacy of family relationships and essential loyalties, as well as by the expression of emotional excess. Finally, the acceptance of the movie by the audience, which was characterized by the consensus towards the regional representation shown in the movie, will be commented on.

  6. Desarrollo postembrionario de Ronderosia bergi (Orthoptera: Acrididae: Melanoplinae bajo condiciones controladas

    Directory of Open Access Journals (Sweden)

    Yanina MARIOTTINI

    2006-01-01

    Full Text Available Mediante el seguimiento de cohortes correspondientes a la primera generación de bioterio, provenientes de ejemplares capturados en el sudeste de la provincia de San Luis, se registraron algunos parámetros biológicos fundamentales del acridio Ronderosia bergi (Stål bajo condiciones controladas (30°C, 40% HR; 14hs. luz, 10 hs. oscuridad. La duración total del desarrollo postembrionario fue de 213 días, de los cuales 30 correspondieron a los cinco estadios del desarrollo ninfal. El número promedio de huevos por postura fue de 16,8, y la madurez sexual fue alcanzada dentro de los 4-5 días después del ingreso a imago. Las diferencias con los escasos datos provenientes de estudios previos, obedecerían a las distintas condiciones de crianza o a una alta variabilidad intraespecífica.

  7. Bajo peso al nacer y su implicación en el desarrollo psicomotor

    Directory of Open Access Journals (Sweden)

    Doris Amparo Parada-Rico

    2015-12-01

    Full Text Available Los niños que al nacer presentan peso bajo, pueden desarrollar graves problemas de salud, así mismo, el riesgo de sufrir problemas e incapacidades en su desarrollo psicomotor a largo plazo es mayor. En la revisión en bases de datos científicas, se identifica como un problema de salud a escala mundial, puesto que estos recién nacidos pueden tener serias limitaciones en su supervivencia y posteriormente en su calidad de vida; por ende, se debe evaluar minuciosamente su desarrollo psicomotor, de manera que se asegure la detección temprana de factores de riesgo susceptibles a intervenciones de cuidado.

  8. Comportamiento del fruto de uchuva Physalis peruviana L., bajo diferentes temperaturas de almacenamiento

    Directory of Open Access Journals (Sweden)

    Elberth Hernando Pinzón

    2015-12-01

    Full Text Available El fruto de la uchuva Physalis peruviana L. es muy apetecido en los mercados internacionales, por sus características nutracéuticas; sin embargo, por ser un fruto climatérico, los procesos de maduración se dan de forma acelerada disminuyendo considerablemente su vida poscosecha. Teniendo en cuenta lo anterior se han desarrollado diferentes técnicas que permiten desacelerar los procesos normales de maduración, entre las que se encuentran, la modificación de atmósferas o el almacenamiento a diferentes temperaturas, siendo éste último, muy utilizado por la facilidad de manejo y bajo costo. Por lo anterior, se evaluó el comportamiento del fruto de uchuva ecotipo Colombia sometido a diferentes temperaturas de almacenamiento, a los que se les evaluó la pérdida de masa fresca, índice de color, firmeza, sólidos solubles totales y acidez total. Se presentaron diferencias significativas para todas las variables evaluadas entre los tratamientos bajo refrigeración y el testigo. La temperatura de almacenamiento, influyó sobre todas las características físicas y químicas evaluadas de manera satisfactoria, ya que luego de 18 días después de almacenamiento los frutos refrigerados conservaron su calidad, siendo favorable para su comercialización; sin embargo, se espera en estudios futuros realizar pruebas de vida en anaquel que permitan descartar fisiopatías que afecten la presentación del producto así como su consumo.

  9. New data about the archaeological area of Marroquíes Bajos: the fifth ditch

    Directory of Open Access Journals (Sweden)

    Sánchez, Alberto

    2005-12-01

    Full Text Available The present paper presents the results that were obtained in the excavation carried out in the plot DOC-1 (SUNP-1 in the Archaeological Area of Marroquíes Bajos. The main contribution of this excavation in the context of all the research done in this archaeological area has to do with its Chalcolithic phase, in particular with the delimitation and documentation of the fifth ditch in an extension that was hitherto unknown. Along with this ditch, a fortified structure was also documented, which consisted of two walls and a semicircular hollow tower which was very likely to protect an entrance. Finally, the research has yielded the first data on the food and health of the people in this settlement by analysing a set of bone remains located on the bottom of the ditch.

    Este trabajo presenta los resultados obtenidos en la excavación realizada en la parcela DOC-1 (SUNP-1 de la Zona Arqueológica de Marroquíes Bajos. La principal aportación de la excavación al ámbito de las investigaciones desarrolladas en esta zona arqueológica se centra en su fase calcolítica, concretamente en la delimitación y documentación del quinto foso en una extensión no conocida hasta el momento. Asociado este foso se documentó igualmente una estructura fortificada compuesta por dos muros y una torre semicircular hueca que muy posiblemente protegía un acceso. Finalmente la investigación desarrollada a permitido obtener los primeros datos sobre alimentación y salud de la población del asentamiento mediante el análisis de un conjunto de restos óseos localizados en el fondo del foso.

  10. Conducting Qualitative Data Analysis: Managing Dynamic Tensions within

    Science.gov (United States)

    Chenail, Ronald J.

    2012-01-01

    In the third of a series of "how-to" essays on conducting qualitative data analysis, Ron Chenail examines the dynamic tensions within the process of qualitative data analysis that qualitative researchers must manage in order to produce credible and creative results. These tensions include (a) the qualities of the data and the qualitative data…

  11. Tensions within Teaching: An Autoethnography of an American Teacher

    Science.gov (United States)

    Tuura, Brianne Marie

    2012-01-01

    This dissertation examines the personal transformation of an American teacher as she becomes aware of the social, political, and economic tensions that exist within the American school system and the affects these tensions have on her ability to teach. As the researcher becomes more aware of power structures surrounding her, the reader is enabled…

  12. Dorzolamide increases retinal oxygen tension after branch retinal vein occlusion

    DEFF Research Database (Denmark)

    Noergaard, Michael Hove; Bach-Holm, Daniella; Scherfig, Erik

    2008-01-01

    To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs.......To study the effect of dorzolamide on the preretinal oxygen tension (RPO(2)) in retinal areas affected by experimental branch retinal vein occlusion (BRVO) in pigs....

  13. Curvature dependence of the electrolytic liquid-liquid interfacial tension

    NARCIS (Netherlands)

    Bier, Markus; de Graaf, J.; Zwanikken, J.W.; van Roij, R.H.H.G.

    2009-01-01

    The interfacial tension of a liquid droplet surrounded by another liquid in the presence of microscopic ions is studied as a function of the droplet radius. An analytical expression for the interfacial tension is obtained within a linear Poisson–Boltzmann theory and compared with numerical results

  14. Measurement for Surface Tension of Aqueous Inorganic Salt

    Directory of Open Access Journals (Sweden)

    Jiming Wen

    2018-03-01

    Full Text Available Bubble columns are effective means of filtration in filtered containment venting systems. Here, the surface tension has a significant influence on bubble size distribution and bubble deformation, which have a strong impact on the behavior of the bubble column. The influence of aqueous inorganic compounds on the surface tension depends on the electrolytic activity, Debye length, entropy of ion hydration, and surface deficiencies or excess. In this work, the surface tensions of same specific aqueous solutions have been measured by different methods including platinum plate method, platinum ring method, and maximum bubble pressure method. The measured surface tensions of both sodium hydroxide and sodium thiosulfate are less than that of water. As solution temperature ranges from 20 to 75°C, the surface tension of 0.5 mol/L sodium hydroxide solution decreases from 71 to 55 mN/m while that of 1 mol/L solution decreases from 60 to 45 mN/m. Similarly during the same temperature range, the surface tension of 0.5 mol/L sodium thiosulfate decreases from 70 to 38 mN/m, and that of 1 mol/L sodium thiosulfate is between 68 and 36 mN/m. The analysis for the influence mechanism of aqueous inorganic on surface tension is provided. In addition, experimental results show that the surface tension of solid aerosol suspension liquid has no obvious difference from that of distilled water.

  15. The tension as perturbative parameter in string theory

    International Nuclear Information System (INIS)

    Gamboa, J.

    1990-01-01

    We propose an approach to string theory where the zero theory is the null string. We find an explicit form of the propagator for the null string in the momentum space. We show that considering the tension as perturbative parameter, the perturbative series is completely summable and we find the propagator of the bosonic open string with tension T. (author) [pt

  16. Corrosion resistance of grouted post-tensioning systems : [summary].

    Science.gov (United States)

    2013-08-01

    The increased popularity of post-tensioned bridge construction in the United States has led to concerns about corrosion and its impact on the life cycle of these bridges. Although the vast majority of post-tensioned bridges in the United States have ...

  17. The Tension between Justice and Freedom in Paulo Freire's Epistemology.

    Science.gov (United States)

    Joldersma, Clarence W.

    2001-01-01

    Explores how the concept of freedom in Paulo Freire's constructivist epistemology-constituted as agentive, spontaneity-based action-is in tension with his ethical project of a pedagogy for justice, one based on responsibility and non-indifference. Resolution of this tension means reconceptualizing the grounding notion of the subject beyond a…

  18. Rapid cable tension estimation using dynamic and mechanical properties

    Science.gov (United States)

    Martínez-Castro, Rosana E.; Jang, Shinae; Christenson, Richard E.

    2016-04-01

    Main tension elements are critical to the overall stability of cable-supported bridges. A dependable and rapid determination of cable tension is desired to assess the state of a cable-supported bridge and evaluate its operability. A portable smart sensor setup is presented to reduce post-processing time and deployment complexity while reliably determining cable tension using dynamic characteristics extracted from spectral analysis. A self-recording accelerometer is coupled with a single-board microcomputer that communicates wirelessly with a remote host computer. The portable smart sensing device is designed such that additional algorithms, sensors and controlling devices for various monitoring applications can be installed and operated for additional structural assessment. The tension-estimating algorithms are based on taut string theory and expand to consider bending stiffness. The successful combination of cable properties allows the use of a cable's dynamic behavior to determine tension force. The tension-estimating algorithms are experimentally validated on a through-arch steel bridge subject to ambient vibration induced by passing traffic. The tension estimation is determined in well agreement with previously determined tension values for the structure.

  19. Planck and the local Universe: quantifying the tension

    CERN Document Server

    Verde, Licia; Protopapas, Pavlos

    2013-01-01

    We use the latest Planck constraints, and in particular constraints on the derived parameters (Hubble constant and age of the Universe) for the local universe and compare them with local measurements of the same quantities. We propose a way to quantify whether cosmological parameters constraints from two different experiments are in tension or not. Our statistic, T, is an evidence ratio and therefore can be interpreted with the widely used Jeffrey's scale. We find that in the framework of the LCDM model, the Planck inferred two dimensional, joint, posterior distribution for the Hubble constant and age of the Universe is in "strong" tension with the local measurements; the odds being ~ 1:50. We explore several possibilities for explaining this tension and examine the consequences both in terms of unknown errors and deviations from the LCDM model. In some one-parameter LCDM model extensions, tension is reduced whereas in other extensions, tension is instead increased. In particular, small total neutrino masses ...

  20. Myosin II dynamics are regulated by tension in intercalating cells.

    Science.gov (United States)

    Fernandez-Gonzalez, Rodrigo; Simoes, Sérgio de Matos; Röper, Jens-Christian; Eaton, Suzanne; Zallen, Jennifer A

    2009-11-01

    Axis elongation in Drosophila occurs through polarized cell rearrangements driven by actomyosin contractility. Myosin II promotes neighbor exchange through the contraction of single cell boundaries, while the contraction of myosin II structures spanning multiple pairs of cells leads to rosette formation. Here we show that multicellular actomyosin cables form at a higher frequency than expected by chance, indicating that cable assembly is an active process. Multicellular cables are sites of increased mechanical tension as measured by laser ablation. Fluorescence recovery after photobleaching experiments show that myosin II is stabilized at the cortex in regions of increased tension. Myosin II is recruited in response to an ectopic force and relieving tension leads to a rapid loss of myosin, indicating that tension is necessary and sufficient for cortical myosin localization. These results demonstrate that myosin II dynamics are regulated by tension in a positive feedback loop that leads to multicellular actomyosin cable formation and efficient tissue elongation.

  1. Identification of source and recharge zones in an aquifer system from water stable isotope. Case Study Bajo Cauca Antioqueno

    International Nuclear Information System (INIS)

    Palacio B, Paola Andrea; Betancur V, Teresita

    2008-01-01

    Hydrology and hydrogeochemical are auxiliary techniques to valid conceptual hydrogeology an recharge models. Stable isotopes from water trace sources and path flow and Tritium indicates age. This paper is about the use of D 18, D 2H y 3H to study the aquifer system on Bajo Cauca antioqueno

  2. Ethnography in community psychology: promises and tensions.

    Science.gov (United States)

    Case, Andrew D; Todd, Nathan R; Kral, Michael J

    2014-09-01

    Community psychology recognizes the need for research methods that illuminate context, culture, diversity, and process. One such method, ethnography, has crossed into multiple disciplines from anthropology, and indeed, community psychologists are becoming community ethnographers. Ethnographic work stands at the intersection of bridging universal questions with the particularities of people and groups bounded in time, geographic location, and social location. Ethnography is thus historical and deeply contextual, enabling a rich, in-depth understanding of communities that is aligned with the values and goals of community psychology. The purpose of this paper is to elucidate the potential of ethnography for community psychology and to encourage its use within the field as a method to capture culture and context, to document process, and to reveal how social change and action occur within and through communities. We discuss the method of ethnography, draw connections to community psychology values and goals, and identify tensions from our experiences doing ethnography. Overall, we assert that ethnography is a method that resonates with community psychology and present this paper as a resource for those interested in using this method in their research or community activism.

  3. Tension pneumothorax due to perforated colon.

    Science.gov (United States)

    Abdullah, Muhammad; Stonelake, Paul

    2016-05-31

    A very rare case of traumatic diaphragmatic hernia is reported in a 65-year-old woman who presented 46 years after her initial thoracoabdominal injury with tension faecopneumothorax caused by a perforated colon in the chest cavity. She presented in a critical condition with severe respiratory distress, sepsis and acute kidney injury. She had a long-standing history of bronchial asthma with respiratory complications and had experienced progressive shortness of breath for the past year. A recent CT scan had excluded the presence of a diaphragmatic hernia but showed a significantly raised left hemidiaphragm. On admission, chest X-rays showed a significantly raised left hemidiaphragm and mediastinal shift, but the possibility of a diaphragmatic hernia with strangulated bowel in the chest was not suspected until the patient was reviewed by the surgical and intensive care unit consultants the next morning and a repeat CT performed. She had a successful outcome after her emergency operation. 2016 BMJ Publishing Group Ltd.

  4. Muscle tension dysphonia in Vietnamese female teachers.

    Science.gov (United States)

    Nguyen, Duong Duy; Kenny, Dianna T; Tran, Ninh Duy; Livesey, Jonathan R

    2009-03-01

    There has been no published research on muscle tension dysphonia (MTD) in speakers who use a tonal language. Using a sample of 47 Northern Vietnamese female primary school teachers with MTD, we aimed to discover whether professional voice users of tonal languages presented with the same symptoms of MTD as speakers of nontonal languages and whether they presented with additional symptoms as a result of speaking a tonal language. The vocal characteristics were assessed by use of a questionnaire and expert perceptual evaluation. Laryngeal features were assessed by photolaryngoscopy. The results showed that MTD was associated with a larger number of vocal symptoms than previously reported. However, the participants did not have the same vocal symptoms reported in English speakers, for example, hard glottal attack, pitch breaks, unusual speech rate, and glottal fry. Factor analysis of the vocal symptoms revealed three factors: "vocal fatigue/hyperfunction," "physical discomfort," and "voice quality," all of which demonstrated high reliability. The major laryngeal characteristic was a glottal gap. The glottal shapes observed included: 44.7% had an incomplete closure, 29.8% a posterior gap, 12.8% an hourglass-shaped gap, 8.5% a spindle-shaped gap, and 4.3% had complete glottal closure. The findings implied a potential contribution of linguistic-specific factors and teaching-related factors to the presentation of this voice disorder in this group of teachers.

  5. BIOFEEDBACK TRAINING AND TENSION-TYPE HEADACHE.

    Science.gov (United States)

    Šecić, Ana; Cvjeticanin, Timon; Kes, Vanja Bašić

    2016-03-01

    Biofeedback is a training method, which connects physiological and psychological processes in a person for the purposes of improving his/her physical, emotional, mental and spiritual health. In biofeedback treatment, an active role of the patient is stressed for him/her to be able to actively control the physiological and emotional processes. The aim of biofeedback is to improve the conscious control of the individual's involuntary physiological activity. Research has shown that biofeedback, either applied alone or in combination with other behavioral therapies (techniques), is an effective treatment for various medical and psychological disorders, from headache and hypertension to temporomandibular and attention deficit disorders. More than 90% of adults experience headache once a year, which makes headache one of the most common symptoms and diagnoses in medicine. Tension-type headaches occur in at least 40% of the population and their impact on the health insurance costs and diminished productivity is significant. Studies have shown that clinical biofeedback training is effective in treating headaches. Moreover, the authors stress the need for additional research and further development of methodology for this kind of research.

  6. Updated constraints on the cosmic string tension

    International Nuclear Information System (INIS)

    Battye, Richard; Moss, Adam

    2010-01-01

    We reexamine the constraints on the cosmic string tension from cosmic microwave background (CMB) and matter power spectra, and also from limits on a stochastic background of gravitational waves provided by pulsar timing. We discuss the different approaches to modeling string evolution and radiation. In particular, we show that the unconnected segment model can describe CMB spectra expected from thin string (Nambu) and field theory (Abelian-Higgs) simulations using the computed values for the correlation length, rms string velocity and small-scale structure relevant to each variety of simulation. Applying the computed spectra in a fit to CMB and SDSS data we find that Gμ/c 2 -7 (2σ) if the Nambu simulations are correct and Gμ/c 2 -7 in the Abelian-Higgs case. The degeneracy between Gμ/c 2 and the power spectrum slope n S is substantially reduced from previous work. Inclusion of constraints on the baryon density from big bang nucleosynthesis (BBN) imply that n S 2 and loop production size, α, we find that Gμ/c 2 -7 for αc 2 /(ΓGμ) 2 -11 /α for αc 2 /(ΓGμ)>>1.

  7. Ocular Blood Flow and Normal Tension Glaucoma

    Directory of Open Access Journals (Sweden)

    Ning Fan

    2015-01-01

    Full Text Available Normal tension glaucoma (NTG is known as a multifactorial optic neuropathy characterized by progressive retinal ganglion cell death and glaucomatous visual field loss, even though the intraocular pressure (IOP does not exceed the normal range. The pathophysiology of NTG remains largely undetermined. It is hypothesized that the abnormal ocular blood flow is involved in the pathogenesis of this disease. A number of evidences suggested that the vascular factors played a significant role in the development of NTG. In recent years, the new imaging techniques, fluorescein angiography, color Doppler imaging (CDI, magnetic resonance imaging (MRI, and laser speckle flowgraphy (LSFG, have been used to evaluate the ocular blood flow and blood vessels, and the impaired vascular autoregulation was found in patients with NTG. Previous studies showed that NTG was associated with a variety of systemic diseases, including migraine, Alzheimer’s disease, primary vascular dysregulation, and Flammer syndrome. The vascular factors were involved in these diseases. The mechanisms underlying the abnormal ocular blood flow in NTG are still not clear, but the risk factors for glaucomatous optic neuropathy likely included oxidative stress, vasospasm, and endothelial dysfunction.

  8. Tension tests of concrete containment wall elements

    International Nuclear Information System (INIS)

    Schultz, D.M.; Julien, J.T.; Russel, H.G.

    1984-01-01

    Tension tests of concrete containment wall elements were conducted as part of a three-phase research program sponsored by the Electric Power Research Institute (EPRI). The objective of the EPRI experimental/analytical program is twofold. The first objective is to provide the utility industry with a test-verified analytical method for making realistic estimates of actual capacities of reinforced and prestressed concrete containments under internal over-pressurization from postulated degraded core accidents. The second objective is to determine qualitative and quantitative leak rate characteristics of typical containment cross-sections with and without penetrations. This paper covers the experimental portion to the EPRI program. The testing program for Phase 1 included eight large-scale specimens representing elements from the wall of a containment. Each specimen was 60-in (1525-mm) square, 24-in (610-mm) thick, and had full-size reinforcing bars. Six specimens were representative of prototypical reinforced concrete containment designs. The remaining two specimens represented prototypical prestressed containment designs. Various reinforcement configurations and loading arrangements resulted in data that permit comparisons of the effects of controlled variables on cracking and subsequent concrete/reinforcement/liner interaction in containment elements. Subtle differences, due to variations in reinforcement patterns and load applications among the eight specimens, are being used to benchmark the codes being developed in the analytical portion of the EPRI program. Phases 2 and 3 of the test program will examine leak rate characteristics and failure mechanisms at penetrations and structural discontinuities. (orig.)

  9. Peran Tradisi Lisan Iko-Iko Berbasis Sastra Melayu dalam Penguatan Komunitas Etnis Bajo

    Directory of Open Access Journals (Sweden)

    I Ketut Suardika

    2016-12-01

    Full Text Available Etnia Bajo merupakan  suatu komunitas berbudaya  Melayu hidup secara berkelompok  di berbagai wilayah pesisir pantai dan pulau terpencil eli Nusantara dan Asia Tenggara. Di Kawasan Barat Indonesia dan Malay­ sia Barat disebut Orang Laut, atau Suku Laut. Di Malaysia Timur, Brunai Darussalam, dan Philipina disebut Orang Bajau.Meskipun memiliki nama yang berbeda-beda berdasarkan  geografis tempat tinggalnya, tetapi dari segi  budaya  memiliki  persamaan  khususnya  proses  pewarisan  pengetahuan,  nilai, dan  keterampilan dalam bentuk  penguatan  komunitas  melalui tradisi lisan Iko-iko, nauya (nyanyian dan pantun. Beberapa kajian  menunjukkan   bahwa  Etnis  Bajo  ini  berasal  dari  Selat  Malaka,  selanjutnya   mereka  tersebar  di kawasan  Kepulauan  Melayu  (Malaysia,  Indonesia,  Brunai Darussalam, dan Philipina  akibat  kedatangan imperialisme  Portugis  yang merebut  Malaka  pada tahun 1511, Orang Bajo  sebagai salah satu inti rakyat Kerajaan Malaka bangkit melawan Imperialisme Portugis, setelah kerajaannya  takluk. mereka tetap melan­ jutkan perlawanan  eli laut dengan tersebar  di eli berbagai  kawasan tersebut. Pola pemukiman  yang semi­ nomaden  sebagai  nelayan  tradisional,  mengakibatkan  mereka mengembangkan sistem  pembelajaran  asli (learning comunitas system. Salah satu media pembelajaran  yang banyak digunakan adalah iko-iko (cerita kepahlawanan, jenis  tradisi  lisan  ini terancam  punah karena  kurang  eliminati generasi  muda, umumnya mereka yang bisa mengisahkannya berusia sekitar 50 tahun ke atas. Tradisi sastra iko-iko berperan menyam­ paikan pesan  moral dan semangat  juang yang dituturkan  secara lisan  dari generasi  ke generasi, berkisah tentang kepahlawanan dan elibawakan selama beberapa jam yang dinyanyikan menjelang tidur dan atau saat dalam  pelayaran.  Ciri  khas  iko-iko  adalah  lirik  dan baitnya  secara  teratur  yang

  10. LA PATAGONIA COMO TERRITORIO EN DISPUTA: TENSIONES ENTRE EL ESTADO, LA IGLESIA Y LA CONGREGACIÓN SALESIANA POR EL ESPACIO MISIONERO

    Directory of Open Access Journals (Sweden)

    María Nicoletti

    2012-06-01

    Full Text Available La Patagonia fue el primer territorio salesiano “ad gentes”. La creación de su administración bajo la figura de un Vicariato y Prefectura apostólica de parte de la Congregación Salesiana y el Colegio de Propaganda Fide, trajo aparejados numerosos conflictos con las Iglesias Argentina y Chilena y con ambos Estados nacionales. Estos conflictos, en el marco histórico de la construcción de las naciones del siglo XIX y principios del siglo XX, fueron acompañados por los planes de evangelización que la Congregación salesiana había formulado para los pueblos originarios. Bajo la gestión y dirección de los dos primeros rectores mayores de la Congregación, Don Bosco y Don Rua, se resolvieron los problemas con las Iglesias y Estados de ambas naciones, cargados de tensiones en la construcción del territorio de evangelización considerado según cada institución como “terra nullius”, “territorio salesiano” o “territorio nacional y diocesano”.

  11. Ultrasound Findings in Tension Pneumothorax: A Case Report.

    Science.gov (United States)

    Inocencio, Maxine; Childs, Jeannine; Chilstrom, Mikaela L; Berona, Kristin

    2017-06-01

    Delayed recognition of tension pneumothorax can lead to a mortality of 31% to 91%. However, the classic physical examination findings of tracheal deviation and distended neck veins are poorly sensitive in the diagnosis of tension pneumothorax. Point-of-care ultrasound is accurate in identifying the presence of pneumothorax, but sonographic findings of tension pneumothorax are less well described. We report the case of a 21-year-old man with sudden-onset left-sided chest pain. He was clinically stable without hypoxia or hypotension, and the initial chest x-ray study showed a large pneumothorax without mediastinal shift. While the patient was awaiting tube thoracostomy, a point-of-care ultrasound demonstrated findings of mediastinal shift and a dilated inferior vena cava (IVC) concerning for tension physiology, even though the patient remained hemodynamically stable. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case demonstrates a unique clinical scenario of ultrasound evidence of tension physiology in a clinically stable patient. Although this patient was well appearing without hypotension, respiratory distress, tracheal deviation, or distended neck veins, point-of-care ultrasound revealed mediastinal shift and a plethoric IVC. Given that the classic clinical signs of tension pneumothorax are not uniformly present, this case shows how point-of-care ultrasound may diagnose tension pneumothorax before clinical decompensation. Published by Elsevier Inc.

  12. Automated wireless monitoring system for cable tension using smart sensors

    Science.gov (United States)

    Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jongwoong; Cho, Soojin; Spencer, Billie F.; Yun, Chung-Bang

    2013-04-01

    Cables are critical load carrying members of cable-stayed bridges; monitoring tension forces of the cables provides valuable information for SHM of the cable-stayed bridges. Monitoring systems for the cable tension can be efficiently realized using wireless smart sensors in conjunction with vibration-based cable tension estimation approaches. This study develops an automated cable tension monitoring system using MEMSIC's Imote2 smart sensors. An embedded data processing strategy is implemented on the Imote2-based wireless sensor network to calculate cable tensions using a vibration-based method, significantly reducing the wireless data transmission and associated power consumption. The autonomous operation of the monitoring system is achieved by AutoMonitor, a high-level coordinator application provided by the Illinois SHM Project Services Toolsuite. The monitoring system also features power harvesting enabled by solar panels attached to each sensor node and AutoMonitor for charging control. The proposed wireless system has been deployed on the Jindo Bridge, a cable-stayed bridge located in South Korea. Tension forces are autonomously monitored for 12 cables in the east, land side of the bridge, proving the validity and potential of the presented tension monitoring system for real-world applications.

  13. Habilidades pre-escolares de los niños nacidos prematuramente y con bajo peso

    Directory of Open Access Journals (Sweden)

    Sasha A. Martínez-Espiet

    2016-06-01

    Full Text Available RESUMEN: El objetivo de este estudio fue conocer el nivel de desarrollo en la etapa pre-escolar de un grupo de niños nacidos prematuramente y con bajo peso. Se evaluó un grupo 20 niños de cuatro años nacidos prematuramente y con bajo peso y un grupo de 20 niños nacidos luego de gestación completada y peso deseado utilizando la prueba de integración visual-motora Beery-Buktenica. Además, se administró el cuestionario del desarrollo Ages and Stages (ASQ-3 a las 40 madres. El análisis estadístico se llevó a cabo mediante una prueba t de studentpara grupos independientes. El grupo de niños nacidos prematuramente obtuvo puntuaciones significativamente inferiores en las pruebas que medían las habilidades de percepción visual (µ1 83.65 ; µ2 93.7 (p=0.0001, integración visual-motora (µ1 93.6 ; µ2 104.8 (p=0.001 y motor fina (µ1 36.00 ; µ2 44.25 (p=0.033 al ser comparados con el grupo de niños nacidos luego de una gestacióncompletada.El estudio sugiere que los niños nacidos prematuramente y con bajo peso presentan menor ejecución en el desarrollo sensorio-motor durante la etapa pre-escolar. Estas desventajas pasan desapercibidas y pueden representar rezago en las tareas escolares futuras que requieren de dichas habilidades. Es importante fomentar la evaluación y estimulación ambiental temprana en esta población aún en ausencia de indicadores de riesgo. ABSTRACT: The purpose of this study was to evaluate the development among a group of pre-school children born premature and with low weight. We evaluated a group of four years old children; 20 children born prematurely and 20 children born after a full gestation and desired weight, using the Beery-Buktenica visual-motor integration test. We also administered the Ages and Stages Questionnaire (ASQ-3 development test to all 40 mothers. Statistical analysis was performed using student t test for independent groups. The group of children born prematurely scored significantly lower

  14. Bajo peso al nacer, crecimiento y desarrollo en el primer año de vida

    Directory of Open Access Journals (Sweden)

    Elia Rosa Lemus Lago

    1997-04-01

    Full Text Available Se efectuó un estudio descriptivo, longitudinal y retrospectivo en el área de salud del Policlínico Docente "19 de Abril" con los niños nacidos con peso inferior a los 2 500 g, en el año 1994, y se siguió su evolución clínica durante el primer año de vida, que correspondió a una muestra de 23 infantes. Los datos fueron recogidos de las historias clínicas individuales de los niños y de la embarazada. Se analizaron los parámetros peso, talla, circunsferencia cefálica, valoración nutricional y desarrollo psicomotor. Predominó el bajo peso para la edad gestacional con un 65,2 y el 34,7 % correspondió a los nacidos antes del término de la gestación. El 100 % de los pretérmino al año de vida tuvieron una valoración nutricional normal. No se comportaron de igual forma los de bajo peso para la edad gestacional en los que el 20 % quedaron por debajo del 3er. percentil.A descriptive, longitudinal and retrospective study was conducted at the health area of the "19 de Abril" Teaching Polyclinic. 23 infants who were born in 1994 with a birth weight < 2 500 g were included in the sample. Their clinical evolution was followed during the first year of life. The data were obtained from the individual medical histories of the children and of the pregnant women. The following parameters were analyzed: weight, size, cephalic perimeter, nutritional assessment and psychomotor development. Low weight prevailed for the gestational age with 65.2 %, whereas 34.7 % corresponded to preterm deliveries. 100 % of the preterm infants had a normal nutritional assessment after the first year of life. However, 20 % of those with low weight at the gestational age remained under the third percentile.

  15. Peso bajo, sobrepeso, obesidad y crecimiento en adolescentes en el Perú 2009-2010

    Directory of Open Access Journals (Sweden)

    Jaime Pajuelo R

    2015-04-01

    Full Text Available Introducción: El grupo de adolescentes representan, de alguna manera, la quinta parte de la población y no se encuentran al margen de los problemas nutricionales. Objetivos: Conocer la situación nutricional, el crecimiento y algunos factores determinantes, en adolescentes en el Perú. Diseño: Estudio descriptivo, observacional, transversal. Participantes: Adolescentes. Intervenciones: En 14 753 adolescentes de 10 a 19 años se obtuvo el peso, talla, índice de masa corporal (IMC. Se utilizó la referencia percentilar de Must y los puntajes Z de OMS. Principales medidas de resultados: Promedios y DE. Prevalencias IC 95%. OR IC 95%. Chi-cuadrado y regresión múltiple. Resultados: Se encontró prevalencias de 2,6; 5,9; 79; 9,3 y 3,2 (Must; 0,2; 1,1; 82,6; 12,5; 3,5% (OMS de déficit, peso bajo, normal, sobrepeso y obesidad, respectivamente. Predominó el sobrepeso-obesidad en áreas urbanas, en los no pobres, en la costa, selva y Lima Metropolitana, en los que vivían por debajo de 3 000 msnm. Los factores de riesgo para el déficit-bajo peso fueron: género masculino, pobres extremos, pobres no extremos, vivir en la costa norte y sierra centro, y como factor protector los que estaban por debajo de los 1 000 msnm. Los factores de riesgo del sobrepeso-obesidad fueron el vivir en áreas urbanas, costa sur y por debajo de los 1 000 msnm, los que vivían entre los 1 000 y 2 999 msnm; y los factores de protección fueron el ser pobre extremo, el pobre no extremo, vivir en costa norte, sierra norte, sierra centro y sierra sur y selva. El 28,5% presentó retardo de crecimiento (adolescentes de 10 a 17 años. Los factores de riesgo del retardo de crecimiento fueron: vivir en áreas rurales, en la mayoría de los dominios geográficos excepto la costa sur, los niveles de pobreza (extrema y no extrema, los niveles de altitud (1 000 a 2 999 y más de 3 000 msnm. Conclusiones: El sobrepeso-obesidad es el problema de mayor magnitud en los adolescentes

  16. lnteracciones medicamentosas en pacientes bajo tratamiento con itraconazol para diferentes tipos de micosis

    Directory of Open Access Journals (Sweden)

    Adriana L. Fernández

    1999-12-01

    Full Text Available Algunos estudios han reportado un aumento en la frecuencia e importancia de las interacciones del itraconazol en pacientes bajo polifarmacia con fármacos que afectan el sistema enzimático de la citocromo P450 y modifican el metabolismo del azol. Con el propósito de determinar las características epidemiológicas, farmacológicas y clínicas de las interacciones medicamentosas en pacientes bajo tratamiento con itraconazol para diferentes tipos de micosis, se realizó un estudio descriptivo transversal retrospectivo en el que se analizaron 21 historias clínicas de pacientes atendidos en la Corporación para Investigaciones Biológicas durante el período 1994-1997. Entre la población estudiada, seis pacientes presentaron paracoccidioidomicosis; cinco, cromoblastomicosis; cuatro, histoplasmosis; cuatro, criptococosis, y dos, aspergilosis. En promedio, la dosis de itraconazol, la duración y el número de fármacos recibidos concomitantes fueron 223,8 mgldia, 44,3 semanas y 2,7 fármacos, respectivamente. En 10 individuos, se presentaron enfermedades de base y en 15, enfermedades concomitantes. Se documentó interacción medicamentosa (niveles no detectables o no terapéuticos de itraconazol en 18 pacientes, de los cuales 17 presentaban sospecha clínica y 14 sospecha paraclínica de interacción. El medicamento más frecuentemente involucrado con interacción fue la rifampicina, seguido de los inhibidores H, antiácidos y fenitoina. Similar a lo encontrado en otros estudios, la administración concomitante de estos fármacos con el itraconazol, reduce los niveles séricos de este último y altera la respuesta clínica al tratamiento. Este estudio es una aproximación inicial, aún no realizada en nuestra población, que permitirá establecer protocolos para el manejo y prevención de interacciones medicamentosas en pacientes en tratamiento con itraconazol y otros fármacos.

  17. Bending Under Tension Test with Direct Friction Measurement

    DEFF Research Database (Denmark)

    Andreasen, Jan Lasson; Olsson, David Dam; Chodnikiewicz, K.

    2004-01-01

    A special BUT-transducer has been developed in which friction around the tool radius can be directly measured when drawing a plane sheet strip around a cylindrical tool-pin under constant back tension. The front tension, back tension and torque on the tool-pin are all measured directly, thus...... enabling accurate measurement of friction and direct determination of lubricant film breakdown for varying normal pressure, sliding speed, tool radius and tool preheat temperature. The transducer is applied in an experimental investigation focusing on limits of lubrication in drawing of stainless steel...

  18. On innovation patterns and value-tensions in public services

    DEFF Research Database (Denmark)

    Fuglsang, Lars; Rønning, Rolf

    2015-01-01

    to the possibility of intertwined innovation patterns. Focusing public sector services, this paper agues that intertwined innovation patterns emerge within public services as a response to value-tensions. Values can be defined as measures for beneficial behaviour that guide innovation. Value-tensions in public...... services include tensions between the political, economic, communal, aesthetic and intellectual values. The contribution of the paper to service innovation research is the emphasis on the concept of intertwined innovation patterns, such as the intertwinement of science driven and task driven innovation....... Further, the paper contributes by pinpointing how varied values guide innovation in public services....

  19. Tension in the recent Type Ia supernovae datasets

    International Nuclear Information System (INIS)

    Wei, Hao

    2010-01-01

    In the present work, we investigate the tension in the recent Type Ia supernovae (SNIa) datasets Constitution and Union. We show that they are in tension not only with the observations of the cosmic microwave background (CMB) anisotropy and the baryon acoustic oscillations (BAO), but also with other SNIa datasets such as Davis and SNLS. Then, we find the main sources responsible for the tension. Further, we make this more robust by employing the method of random truncation. Based on the results of this work, we suggest two truncated versions of the Union and Constitution datasets, namely the UnionT and ConstitutionT SNIa samples, whose behaviors are more regular.

  20. Tension pneumothorax, is it a really life-threatening condition?

    Science.gov (United States)

    2013-01-01

    Background Tension pneumothorax is a life-threatening occurrence that is infrequently the consequence of spontaneous pneumothorax. The aim of this study was to identify the risk factors for the development of tension pneumothorax and its effect on clinical outcomes. Methods We reviewed patients who were admitted with spontaneous pneumothorax between August 1, 2003 and December 31, 2011. Electronic medical records and the radiological findings were reviewed with chest x-ray and high-resolution computed tomography scans that were retrieved from the Picture Archiving Communication System. Results Out of the 370 patients included in this study, tension pneumothorax developed in 60 (16.2%). The bullae were larger in patients with tension pneumothorax than in those without (23.8 ± 16.2 mm vs 16.1 ± 19.1 mm; P = 0.007). In addition, the incidence of tension pneumothorax increased with the lung bulla size. Fibrotic adhesion was more prevalent in the tension pneumothorax group than in that without (P = 0.000). The bullae were large in patients with fibrotic adhesion than in those without adhesion (35.0 ± 22.3 mm vs 10.4 ± 11.5 mm; P = 0.000). On multivariate analysis, the size of bullae (odds ratio (OR) = 1.03, P = 0.001) and fibrotic adhesion (OR = 10.76, P = 0.000) were risk factors of tension pneumothorax. Hospital mortality was 3.3% in the tension pneumothorax group and it was not significantly different from those patients without tension pneunothorax (P = 0.252). Conclusions Tension pneumothorax is not uncommon, but clinically fatal tension pneumothorax is extremely rare. The size of the lung bullae and fibrotic adhesion contributes to the development of tension pneumothorax. PMID:24128176

  1. Surface tension modelling of liquid Cd-Sn-Zn alloys

    Science.gov (United States)

    Fima, Przemyslaw; Novakovic, Rada

    2018-06-01

    The thermodynamic model in conjunction with Butler equation and the geometric models were used for the surface tension calculation of Cd-Sn-Zn liquid alloys. Good agreement was found between the experimental data for limiting binaries and model calculations performed with Butler model. In the case of ternary alloys, the surface tension variation with Cd content is better reproduced in the case of alloys lying on vertical sections defined by high Sn to Zn molar fraction ratio. The calculated surface tension is in relatively good agreement with the available experimental data. In addition, the surface segregation of liquid ternary Cd-Sn-Zn and constituent binaries has also been calculated.

  2. Secuelas del neurodesarrollo de recién nacidos prematuros de extremadamente bajo peso y de muy bajo peso a los dos años de edad, egresados de la Unidad de Cuidados Intensivos Neonatales del Hospital Nacional Edgardo Rebagliati Martins 2009-2014

    OpenAIRE

    Fernández Sierra, Carmen; Matzumura Kasano, Juan; Gutiérrez Crespo, Hugo; Zamudio Eslava, Luisa; Melgarejo García, Giannina

    2017-01-01

    Objetivo: Describir las secuelas del neurodesarrollo de los recién nacidos prematuros de extremadamente bajo peso y de muy bajo peso a los dos años de edad, egresados de la Unidad de Cuidados Intensivos Neonatales del Hospital Nacional Edgardo Rebagliati Martins. Materiales y métodos: Estudio descriptivo, retrospectivo, transversal en una población de 190 prematuros de extremadamente bajo peso y de muy bajo peso que nacieron durante enero 2009 a junio del 2014, egresados de la Unidad de Cuida...

  3. Climate-derived tensions in Arctic security.

    Energy Technology Data Exchange (ETDEWEB)

    Backus, George A.; Strickland, James Hassler

    2008-09-01

    Globally, there is no lack of security threats. Many of them demand priority engagement and there can never be adequate resources to address all threats. In this context, climate is just another aspect of global security and the Arctic just another region. In light of physical and budgetary constraints, new security needs must be integrated and prioritized with existing ones. This discussion approaches the security impacts of climate from that perspective, starting with the broad security picture and establishing how climate may affect it. This method provides a different view from one that starts with climate and projects it, in isolation, as the source of a hypothetical security burden. That said, the Arctic does appear to present high-priority security challenges. Uncertainty in the timing of an ice-free Arctic affects how quickly it will become a security priority. Uncertainty in the emergent extreme and variable weather conditions will determine the difficulty (cost) of maintaining adequate security (order) in the area. The resolution of sovereignty boundaries affects the ability to enforce security measures, and the U.S. will most probably need a military presence to back-up negotiated sovereignty agreements. Without additional global warming, technology already allows the Arctic to become a strategic link in the global supply chain, possibly with northern Russia as its main hub. Additionally, the multinational corporations reaping the economic bounty may affect security tensions more than nation-states themselves. Countries will depend ever more heavily on the global supply chains. China has particular needs to protect its trade flows. In matters of security, nation-state and multinational-corporate interests will become heavily intertwined.

  4. Differences of optic disc appearance between normal tension and high tension glaucoma patients

    Directory of Open Access Journals (Sweden)

    Stojčić Milan

    2011-01-01

    Full Text Available Introduction. The term glaucoma is used to cover a wide range of diseases, whose main feature is optic neuropathy. According to the level of intraocular pressure (IOP, the open angle glaucoma is arbitrarily divided into high tension glaucoma (HTG and normal tension glaucoma (NTG. Objective. The aim of this study was to investigate the differences of optic disc cup appearance between patients with NTG and HTG. Methods. Prospective study included 30 patients (60 eyes with NTG and 30 patients (60 eyes with HTG. IOP was measured by Goldmann applanation tonometry. Examination of optic disc head was performed by indirect ophthalmoscopy with Volk 90 D superfield lens through a dilated pupil to observe qualitative and quantitative parameters. Visual fields were examined in all patients with the Octopus program G1, full threshold strategy (Octopus 500 EZ, Interzeag, Switzerland. Results. Vertical form of optic disc cup was present in 11 eyes with NTG (18.3% and three eyes with HTG (5% (p<0.05. A disc with localized tissue loss (polar notching on the inferior pole was observed in eight eyes with NTG (13.3% and in one eye with HTG (1.7% (p<0.01. Uniformly enlarged, round cup was more frequent in patients with HTG than NTG: 93.3% and 68.3% respectively (p<0.05. Conclusion. The perceived differences indicate a complex multifactorial nature of glaucoma disease and a possible existence of two pathophysiological ways of optic disc changes within the same basic disease.

  5. Palmito de pejibaye (Bactris gasipaes cultivado bajo diferentes densidades de laurel (Cordia alliodora

    Directory of Open Access Journals (Sweden)

    Johnny Montenegro

    2001-01-01

    Full Text Available Se evalu6 el incremento en altura y gro- SOT de rebrotes, la altura del tallo dominante, la alliodoproducci6n de palmito y el numero de rebrotes diapOT cepa en plantaciones sin y bajo 2 poblacio- domines de laurel (92 y 370 arboles/ha y el efecto ofdel sombreamiento, en la zona Atlantica de Costa Rica. Se observ6 un mayor incremento en el diametro y la altura de los rebrotes en el monocultivo (P=0.0403, P=0.0033 respectiva- mente unicamente en los estadios iniciales de crecimiento. Una mayor altura del tallo princi- pal (P=0.0143se observ6 en la asociaci6n con haraltas densidades de arboles de laurel. EI nume- ro de rebrotes pOT cepa fue mayor (P=0.05 en maxilas parcelas sin la presencia de arboles. Las ma- yores producciones de palmito fueron encon- whetradas en el monocultivo y con 92 arboles ha/(P=O.O 117, determinandose un menor ren- dimiento con mayores niveles de intercepci6n de luz fotosinteticamente activa pOT parte del estrato arb6reo (r=0.68, P=0.0415. Los ingre- monosos fueron mayores en el tratamiento sin arbo- les, los cuales ejercieron un efecto negativo so- bre el rendimiento productivo del cultivo.

  6. COMPETENCIAS PERSONALES Y PROFESIONALES APLICADAS POR GERENTES BAJO ESCENARIOS DE INCERTIDUMBRE ECONÓMICA

    Directory of Open Access Journals (Sweden)

    Jenniz La Madriz

    2016-04-01

    Full Text Available En Venezuela, las compañías de seguro están operando en un entorno económico de incertidumbre, con reducción de ingresos económicos, inflación e inestabilidad financiera. Ante este escenario, la investigación tuvo como objetivo identificar las competencias que aplican los gerentes del área de seguros, para mantener el negocio posicionado en el mercado, tomando como muestra 22 gerentes. El tipo de investigación es de campo, sustentado en los diseños mixtos secuenciales Creswell (2003. Los resultados permitieron identificar que 47,4% de los gerentes encuestados, manifestaron que de las competencias personales que ponen en práctica en su lugar de trabajo, en contextos de incertidumbre económica, están la responsabilidad - comunicación efectiva - resolución de problemas - negociación y trabajar como parte de un grupo. En cuanto a las competencias profesionales, el 52,6% respondieron que está dedicada a gestionar personal, administrar recursos, planificar - organizar estrategias y rendir resultados, bajo escenarios de incertidumbre económica.

  7. Prospectiva de la cadena Productiva de mango bajo el enfoque dinámico

    Directory of Open Access Journals (Sweden)

    Juan Pablo Tribín-Rivera

    2014-01-01

    Full Text Available El propósito del presente documento de investigación, es relacionar los resultados del análisis prospectivo de la cadena productiva de mango en la Provincia del Tequendama – Cundinamarca por medio de dinámica de sistemas, con el fin de compararla desde distintos escenarios; mercado interno frente al mercado externo, y así poder determinar el escenario prospectivo más conveniente para los productores. De igual forma se proponen políticas que mejoren las condiciones de los productores de la región y se relaciona el modelo de simulación por dinámica de sistemas, que puede ser utilizado en diferentes cadenas productivas. La construcción del modelo de simulación se desarrolló con base en las experiencias adquiridas por medio de visitas de campo, recolección de información primaria y secundaria, y la colaboración de expertos que participan, directa o indirectamente, en dicha cadena productiva, enmarcadas bajo el proyecto de investigación titulado “Mercado prospectivo del mango: Comparativo entre el mercado interno y el mercado externo para la Provincia del Tequendama – Cundinamarca”

  8. La gestion bajo una cultura de calidad en Mexico: una verificacion empirica.

    Directory of Open Access Journals (Sweden)

    Rositas, J.

    2004-07-01

    Full Text Available El artículo presenta de entrada, enfoques administrativos que pueden ser englobados en el término “Gestión bajo una cultura de calidad” (GBCC, conocida internacionalmente como Total Quality Management [TQM], o simplemente Gestión de Calidad, citándose en seguida dos puntos de vista contrapunteados a nivel internacional en relación a este enfoque. Se presentan esfuerzos previos de consultores e implantadores mexicanos que, en base al método de casos y de generalizaciones empíricas de sus experiencias profesionales, consideran a la GBCC como una de las grandes tendencias y fuerzas de cambio en el siglo XXI. Se hace referencia a la escasez de investigaciones en las que se ponga a prueba estadísticamente los conceptos de teóricos, practicantes y consultores del área de la calidad. El autor propone y pone a prueba un modelo agregado de ecuaciones estructurales basado en datos de campo de su investigación de doctorado aportados por 45 empresas manufactureras mexicanas. El análisis de datos, realizado con los paquetes de software SPPS y AMOS, arroja coeficientes de regresión y de determinación, así como niveles de bondad del ajuste, altamente significativos. Al concluir, el autor sugiere estrategias adicionales para refinar futuros análisis de datos.

  9. Robot educativo de bajo costo que interpreta melodías en piano

    Directory of Open Access Journals (Sweden)

    Yeison Alberto Buitrago Suescún

    2013-01-01

    Full Text Available Presenta el diseño de un robot educacional que interpreta melodías en un piano. El propósito principal de este robot es servir como instrumento de prácticas en materias relacionadas con fundamentos de robótica, especialmente en los temas de análisis cinemático. Su control se implementó en el software Matlab, que es de uso común en las universidades. Los materiales y equipos utilizados para su implementación son de fáciladquisición y bajo costo, con el fin de que pueda ser replicado fácilmente por un estudiante. La aplicación del intérprete de melodías en un piano estimula a los estudiantes desde edades tempranas a incursionar en esta área tan importante.

  10. Afrontamiento, salud mental y felicidad bajo huelga y ocupación universitaria

    Directory of Open Access Journals (Sweden)

    Emilio Moyano-Díaz

    2017-01-01

    Full Text Available Se identificó la relación entre estrategias de enfrentamiento, salud mental (SM y felicidad en trabajadores de una universidad en huelga y ocupación estudiantil, de acuerdo con status laboral - académico o administrativo-, grado de concordancia con el movimiento estudiantil y sexo. Ciento sesenta y dos participantes respondieron a la Escala de felicidad subjetiva y estrategias de enfrentamiento, y a la Escala de Goldberg (GHQ12. Obtuvimos y discutimos: 1 el uso del humor está asociado con SM y la felicidad y ésta, a la reevaluación cognitiva, enfrentamiento religioso y bajo enfrentamiento de evitación, 2 mayor malestar por la ocupación peor SM, 3 no tener acceso a el espacio de trabajo está asociado con peor SM, más con iguales niveles de felicidad que los que tuvieron acceso, 4 el enfrentamiento varía de acuerdo con el status de académico o administrativo y con el sexo, 5 SM y felicidad no varían de acuerdo con el status académico, 6 aquellos que son pro-movimiento estudiantil presentan mejor SM que aquellos que no lo son.

  11. Modelo matemático de un sistema coordinado productor-comprador bajo el enfoque VMI

    Directory of Open Access Journals (Sweden)

    Fidel Torres

    2012-12-01

    Full Text Available En este trabajo se desarrolla un nuevo modelo matemático de un sistema coordinado productor-comprador mediante un acuerdo de inventarios administrados por el vendedor (VMI. El modelo propuesto considera el tiempo de fabricación del lote e incluye un esquema de sincronización entre el productor y el comprador que facilita la coordinación de la cadena de suministros. El análisis del modelo matemático de coordinación tiene en cuenta las tasas de producción y de demanda y los costos totales anuales de ordenar y mantener inventarios del productor y del comprador. El estudio es complementado por un análisis de sensibilidad que se enfoca sobre los efectos de las variaciones de los parámetros sobre algunas medidas de desempeño en el esquema coordinado VMI entre el productor y el comprador.  Finalmente, se deducen y verifican las condiciones analíticas bajo las cuales la implementación coordinada de VMI otorga beneficios al productor, al comprador y a la cadena de suministros. Los resultados muestran que es posible que el productor y el comprador obtengan beneficios en la implementación de VMI seleccionando una combinación apropiada de los parámetros usando el esquema de coordinación propuesto en una relación gana-gana.

  12. Evaluación de un cluster bajo agricultura protegida en México

    Directory of Open Access Journals (Sweden)

    Luz Evelia Padilla-Bernal

    2012-01-01

    Full Text Available El naciente cluster de tomate bajo agricultura protegida en Zacatecas enfrenta el reto de participar en los mercados globales de una manera sostenible; una respuesta viable para ello es elevar su capacidad de upgrading. En este trabajo se determina la relación entre la eficiencia colectiva en el upgrading del cluster. La información se obtuvo a través de un cuestionario aplicado a técnicos de las unidades de producción (UP, el cual se complementó con entrevistas a propietarios o gerentes, investigadores y funcionarios gubernamentales; posteriormente, se hizo una clasificación de las UP por nivel tecnológico aplicando la técnica de análisis de conglomerado con lo que se obtuvo el índice de eficiencia colectiva, el tipo de gobernanza de las cadenas de valor con las que se relacionan las agroempresas y los tipos de upgrading logrados. Se encontró que las economías externas fueron más dominantes que las acciones conjuntas; la eficiencia colectiva y el upgrading se encuentran positivamente relacionados; asimismo, se observó que el alto nivel tecnológico es condición necesaria, más no suficiente, para que las agroempresas permanezcan competitivas en el mercado global, por lo que se requiere elevar su capacidad de upgrading.

  13. Investigating the tension load of rubber composites by impact ...

    Indian Academy of Sciences (India)

    This work deals with establishing the tension load by impact dynamic testing of rubber composite con- veyor belts. ... top layer ('top cover'), a fabric carcass which provide tensile strength, skim ... components of machines like CBs [20]. CBs of ...

  14. Tension bulla: a cause of reversible pulmonary hypertension.

    Science.gov (United States)

    Waxman, Michael J; Waxman, Jacob D; Forman, John M

    2015-01-01

    A tension pneumothorax represents a medical emergency warranting urgent diagnosis and treatment. A rapidly expanding bulla may resemble the same clinical presentation but requires an entirely different treatment. A 53-year-old woman presented with increasing shortness of breath and her physical examination and chest x-ray were interpreted as showing a tension pneumothorax. A chest tube was placed which did not resolve the process. Placement of a second chest tube was likewise unsuccessful. A chest CT was then performed and was interpreted as showing an unresolved tension pneumothorax, despite seemingly adequate placement of the 2 chest tubes. Further review of the CT showed the border of a giant bulla and a tentative diagnosis was made of a rapidly expanding bulla with tension physiology. Echocardiogram revealed significant pulmonary hypertension. The bulla was surgically excised, the patient had marked improvement in her clinical symptoms and signs, and echocardiographic follow-up showed complete resolution of the pulmonary hypertension.

  15. [Diagnostic and therapy of tension-type headache].

    Science.gov (United States)

    Straube, A

    2014-08-01

    Episodic headache of the tension type is the most prevalent primary headache with a lifetime prevalence of about 78 %. Clinical characteristics are a dull, moderate, holocephalic headache without accompanying autonomic or vegetative symptoms. The episodic tension-type headache often lasts only 30 min up to a maximum of a few days. In contrast to this clinically often undemanding headache, chronic tension-type headache can cause considerable disability in patients. The 1-year prevalence is 1-3 % of the population. All therapy strategies combine nonpharmaceutical therapy such as education of the patient, regular aerobic exercise, and psychological treatment (e.g., Jacobson's progressive muscle relaxation etc.) with pharmaceutical treatment such as tricyclic antidepressants or combined serotonergic and noradrenergic antidepressants. Combination therapy has been proven to be more effective than singular strategies; however, the chronic tension-type headache still poses a therapeutic problem.

  16. Quantifying the BICEP2-Planck tension over gravitational waves.

    Science.gov (United States)

    Smith, Kendrick M; Dvorkin, Cora; Boyle, Latham; Turok, Neil; Halpern, Mark; Hinshaw, Gary; Gold, Ben

    2014-07-18

    The recent BICEP2 measurement of B-mode polarization in the cosmic microwave background (r = 0.2(-0.05)(+0.07)), a possible indication of primordial gravity waves, appears to be in tension with the upper limit from WMAP (r < 0.13 at 95% C.L.) and Planck (r < 0.11 at 95% C.L.). We carefully quantify the level of tension and show that it is very significant (around 0.1% unlikely) when the observed deficit of large-scale temperature power is taken into account. We show that measurements of TE and EE power spectra in the near future will discriminate between the hypotheses that this tension is either a statistical fluke or a sign of new physics. We also discuss extensions of the standard cosmological model that relieve the tension and some novel ways to constrain them.

  17. Corrosion characteristics of unprotected post-tensioning strands under stress.

    Science.gov (United States)

    2014-05-01

    An investigation was conducted to determine the effect of stress condition : and environmental exposure on corrosion of post-tensioned strands during ungrouted periods. : Exposures for periods of up to 4 weeks of stressed, as-received strand placed i...

  18. Machine for winding under tension a prestressing wire

    International Nuclear Information System (INIS)

    Perez, M.A.; Thillet, Georges.

    1975-01-01

    This invention concerns a machine for winding under tension a prestressing wire or cable. It is used in the wrapping of cylindrical structures, particularly concrete vessels, for the purpose of achieving radial prestressing in them [fr

  19. Central and peripheral mechanisms in chronic tension-type headache

    OpenAIRE

    Lipchik, Gay L.; Holroyd, Kenneth A.; France, Christopher R.; Kvaal, Steven A.; Segal, David; Cordingley, Gary E.; Rokicki, Lori A.; McCool, Heidi R.

    1996-01-01

    The second exteroceptive suppression of masseter muscle activity (ES2) and tenderness in pericranial muscles were evaluated in 112 young adults who met IHS criteria in the following diagnostic classifications: 31 chronic tension headache, 31 episodic tension headache, 33 migraine without aura and 17 migraine with aura. An additional 31 subjects served as controls. Pericranial muscle tenderness better distinguished diagnostic subgroups and better distinguished recurrent headache sufferers from...

  20. Precipitating and relieving factors of migraine versus tension type headache

    OpenAIRE

    Haque, Badrul; Rahman, Kazi Mohibur; Hoque, Azharul; Hasan, ATM Hasibul; Chowdhury, Rajib Nayan; Khan, Sharif Uddin; Alam, Mondal Badrul; Habib, Mansur; Mohammad, Quazi Deen

    2012-01-01

    Abstract Background To determine the differences of precipitating and relieving factors between migraine and tension type headache. Methods This is a cross sectional study. We retrospectively reviewed the records of 250 migraine patients and 250 patients diagnosed as tension type headache from the specialized headache clinic in Dept. of Neurology, Dhaka Medical College Hospital. Data were collected through a predesigned questionnaire containing information on age, sex, social status and a pre...

  1. Surface tension and related thermodynamic quantities of aqueous electrolyte solutions

    CERN Document Server

    Matubayasi, Norihiro

    2013-01-01

    Surface tension provides a thermodynamic avenue for analyzing systems in equilibrium and formulating phenomenological explanations for the behavior of constituent molecules in the surface region. While there are extensive experimental observations and established ideas regarding desorption of ions from the surfaces of aqueous salt solutions, a more successful discussion of the theory has recently emerged, which allows the quantitative calculation of the distribution of ions in the surface region. Surface Tension and Related Thermodynamic Quantities of Aqueous Electrolyte Solutions provides a d

  2. Stress measurement and bolt tensioning by ultrasonic methods

    International Nuclear Information System (INIS)

    Smith, J.F.; Greiner, J.D.

    1980-01-01

    In the past decade, a new technique has been developed for measuring tensile stresses in solids. This ultrasonic technique has been used thus far primarily for measuring fastener tension. The precision of measurement is routinely to 2-3% and, with special care, to approx. 1%. The method is insensitive to the frictional losses which plague tensioning by torque wrench. Though the approach is relatively new, it promises a wide range of applicability

  3. Managing the accountability-autonomy tensions in university research commercialisation

    OpenAIRE

    Narayan, Anil K.; Northcott, Deryl; Parker, Lee D.

    2017-01-01

    This article investigates organisational responses to emerging concerns about how accountability–autonomy tensions can be managed within the context of university research commercialisation. The findings suggest that changed expectations of university research practices, which result from the introduction of a commercialisation logic, can be managed via the homogenisation of research goals and strategies. The successful management of accountability–autonomy tensions also depends on utilising ...

  4. The duality of tensions at the workplace for female leaders

    OpenAIRE

    Haidinger, Julia

    2017-01-01

    The qualitative research undertaken was set out to understand the challenges experienced by female leaders at the workplace. Therefore, semi-structured interviews with 12 female leaders in top management positions from different industries were conducted. As a consequence, a duality between tensions concerning 1) character traits, 2) beauty and 3) motherhood was confirmed through the experiences shared by the participants. Women identified these tensions as highly challenging and difficult to...

  5. Managing Tensions Between New and Existing Business Models

    DEFF Research Database (Denmark)

    Sund, Kristian J.; Bogers, Marcel; Villarroel Fernandez, Juan Andrei

    2016-01-01

    Exploring new business models may be a good way to stay competitive, but doing so can create tensions internally, in areas such as organizational structure and competition for resources. Companies exploring business model innovation may not recognize the inevitability of these tensions and thus b...... be poorly prepared to manage them. But understanding these issues may lessen some of the organizational challenges associated with business model innovation....

  6. Stress Measurement and Bolt Tensioning by Ultrasonic Methods

    Science.gov (United States)

    Smith, J. F.; Greiner, John D.

    1980-07-01

    In the past decade, a new technique has been developed for measuring tensile stresses in solids. This ultrasonic technique has been used thus far primarily for measuring fastener tension. The precision of measurement is routinely to 2-3% and, with special care, to ˜1%. The method is insensitive to the frictional losses which plague tensioning by torque wrench. Though the approach is relatively new, it promises a wide range of applicability.

  7. Study on the makinq of Cockroft Walton high tension

    International Nuclear Information System (INIS)

    Hutapea, Sumihar.

    1976-01-01

    A prototype of a generator is being developed at the GAMA Research Center. Experience in working with some components, high voltage capacitor, column, and potential divider is discussed. High voltage diode, the type which is usually used in television, is used. The tension of the generator is measured by using the high ohmic resistence of 4000 megaohm. The maximum tension can be reached no more than 150000 volts. (author)

  8. Nonzero Ideal Gas Contribution to the Surface Tension of Water.

    Science.gov (United States)

    Sega, Marcello; Fábián, Balázs; Jedlovszky, Pál

    2017-06-15

    Surface tension, the tendency of fluid interfaces to behave elastically and minimize their surface, is routinely calculated as the difference between the lateral and normal components of the pressure or, invoking isotropy in momentum space, of the virial tensor. Here we show that the anisotropy of the kinetic energy tensor close to a liquid-vapor interface can be responsible for a large part of its surface tension (about 15% for water, independent from temperature).

  9. Modeling and characterization of strengthened concrete tension members

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Stang, Henrik

    2011-01-01

    The structural potential for cracking of externally strengthened concrete tension members, can be predicted with three parameters, describing the structural cracking potential based on fracture mechanical properties of the of concrete and interface between concrete and strengthening medium....... With these parameters, it is possible to design reinforcement and obtain a required cracking behavior of a given structure. Design recommendations for single and multiple cracking of the tension specimen are given in terms of fracture mechanical parameters, and a structural stiffness parameter....

  10. Contact angle control of sessile drops on a tensioned web

    Science.gov (United States)

    Park, Janghoon; Kim, Dongguk; Lee, Changwoo

    2018-04-01

    In this study, the influence of the change of tension applied to flexible and thin web substrate on the contact angle of sessile drop in roll-to-roll system was investigated. Graphene oxide and deionized water solutions were used in the experiments. Tension was changed to 29, 49, and 69 N, and the casting distance of the micropipette and the material was set to 10, 20, and 40 mm, and the droplet volume was set to 10, 20, and 30 μL, respectively. Statistical analysis of three variables and analysis of the variance methodology showed that the casting distance was most significant for the contact angle change, and the most interesting tension variable was also affected. The change in tension caused the maximum contact angle to change by 5.5°. The tension was not uniform in the width direction. When the droplet was applied in the same direction in the width direction, it was confirmed that the tension unevenness had great influence on the contact angle up to 11°. Finally, the casting distance, which has a large effect on the contact angle, was calibrated in the width direction to reduce the width direction contact angle deviation to 1%. This study can be applied to fine patterning research using continuous inkjet printing and aerosol jet printing, which are roll-to-roll processes based on droplet handling.

  11. Muscle trigger point therapy in tension-type headache.

    Science.gov (United States)

    Alonso-Blanco, Cristina; de-la-Llave-Rincón, Ana Isabel; Fernández-de-las-Peñas, César

    2012-03-01

    Recent evidence suggests that active trigger points (TrPs) in neck and shoulder muscles contribute to tension-type headache. Active TrPs within the suboccipital, upper trapezius, sternocleidomastoid, temporalis, superior oblique and lateral rectus muscles have been associated with chronic and episodic tension-type headache forms. It seems that the pain profile of this headache may be provoked by referred pain from active TrPs in the posterior cervical, head and shoulder muscles. In fact, the presence of active TrPs has been related to a higher degree of sensitization in tension-type headache. Different therapeutic approaches are proposed for proper TrP management. Preliminary evidence indicates that inactivation of TrPs may be effective for the management of tension-type headache, particularly in a subgroup of patients who may respond positively to this approach. Different treatment approaches targeted to TrP inactivation are discussed in the current paper, focusing on tension-type headache. New studies are needed to further delineate the relationship between muscle TrP inactivation and tension-type headache.

  12. Patients with tension-type headaches feel stigmatized

    Directory of Open Access Journals (Sweden)

    Sanjay Prakash

    2016-01-01

    Full Text Available The author, a sufferer of tension-type headache (TTH, believes that the word "tension" in "tension-type headache" carries a social stigma and that patients do not accept a diagnosis of TTH readily. TTH is the most common primary headache disorder. The disability of TTH as a burden of society is greater than that of migraine. Absenteeism because of TTH is higher than that due to migraine. However, patients with TTH do not go for consultation. Even the prevalence of new daily persistent headache (NDPH is 12 times higher at the headache clinic than that of chronic TTH (CTTH. These points hint that TTH patients probably do not want to visit the clinic. The author believes that it could be because of the stigma attached to "tension." Herein, the author has noted the first responses given by 50 consecutive patients with TTH when they were told that they had been suffering from TTH. The first answer of 64% of patients with TTH was "I do not have any tension/stress ." This denial is similar to the denial declared by patients with depression. Depression and tension are similar in the sense that both are considered as a signs of personal weakness. Such a preconception in the society creates a stigma, and patients deny the diagnosis, conceal symptoms, and become reluctant to seek help and treatment.

  13. Producción de biogás a partir de residuos organicos en biodigestores de bajo coste

    OpenAIRE

    Ferrer Martí, Ivet; Uggetti, Enrica; Poggio, Davide; Velo García, Enrique

    2015-01-01

    PRODUCCIÓN DE BIOGÁS A PARTIR DE RESIDUOS ORGANICOS EN BIODIGESTORES DE BAJO COSTE Ivet Ferrer*, Enrica Uggetti**, Davide Poggio***, Enric Velo**** Grup de Recerca en Cooperació i Desenvolupament Humà C. Jordi Girona, 31 08034 - Barcelona, Spain Phone: +34 93 401 64 63 Pàgina web: http://www.upc.edu/grecdh *, **, ***, **** Palabras clave: Digestión anaerobia; Biodigestor; Biogás; Energía; Fertilizante. RESUMEN ...

  14. Jenis dan Status Konservasi Ikan Hiu yang Tertangkap di Tempat Pelelangan Ikan (TPI Labuan Bajo, Manggarai Barat, Flores

    Directory of Open Access Journals (Sweden)

    Ismail Syakurachman Alaydrus

    2016-03-01

    Full Text Available The study aimed to determine the types of sharks are caught, sold and conservation status in the fish auction place (TPI Labuan Bajo, West Manggarai, Flores, East Nusa Tenggara have been conducted in February and March 2014 in Labuan Bajo. The research method was the survey method and used Market Survey sampling techniques and identification by Rapid Assessment method. Descriptively analyzed data, displayed in the form of narration and a table. Based on the results of the study, found 114 individual sharks, 55 individual males, 59 females were classified into three orders, namely Orectolobiformes, Lamniformes, and Carcharhiniformes; 4 families that Carcharhinidae, Odontaspididae, Rhynchobatidae, and Ginglymostomatidae; 5 genera namely Carcharhinus, Triaenodon, Rhyncobatus, Prionace, and Rhizoprionodon and 9 types of sharks that Carcharhinus melanopterus, Triaenodon obesus, Carcharhinus limbatus, Carcharhinus taurus, Carcharhinus amblyrhynchos, Rhynchobatus australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus. Based on the state of conservation, shark found in Labuan Bajo TPI classified Vulnerable and Near Threatened, the dominant type of shark found is Carcharhinus melanopterus (91 fishes while the least was found is Rhynchobatus australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus (each 1 individual.

  15. Perceiving the affordance of string tension for power strokes in badminton: expertise allows effective use of all string tensions.

    Science.gov (United States)

    Zhu, Qin

    2013-01-01

    Affordances mean opportunities for action. These affordances are important for sports performance and relevant to the abilities developed by skilled athletes. In racquet sports such as badminton, different players prefer widely different string tension because it is believed to provide opportunities for effective strokes. The current study examined whether badminton players can perceive the affordance of string tension for power strokes and whether the perception of affordance itself changed as a function of skill level. The results showed that string tension constrained the striking performance of both novice and recreational players, but not of expert players. When perceptual capability was assessed, perceptual mode did not affect perception of the optimal string tension. Skilled players successfully perceived the affordance of string tension, but only experts were concerned about saving energy. Our findings demonstrated that perception of the affordance of string tension in badminton was determined by action abilities. Furthermore, experts could adjust the action to maintain a superior level of performance based on the perception of affordance.

  16. Microbiological corrosion in low carbon steels; Corrosion microbiologica en aceros de bajo carbono

    Energy Technology Data Exchange (ETDEWEB)

    Medina-Custodio, O; Ortiz-Prado, A; Jacobo-Armendariz, V. H; Schouwenaars-Franssens, R [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: medina_1979@yahoo.com; armandoo@servidor.unam.mx; vjacobo@dgapa.unam.mx; raf_schouweenaars@yahoo.com

    2009-01-15

    The Microbiologically Induced Corrosion affects several industries, such as oil industry where it is estimated that 20% to 30% pipes failures are related with microorganism. The chemical reactions generate ions transfer, this validate the use of electrochemical technique for its analysis. Coupons submerged in a nutritional medium with presence and absence of three different microorganisms during two periods, 48 hours and 28 days were studied. Polarization resistance (Rp) and Electrochemical Impedance Spectroscopy (EIS) techniques were applied to determine the corrosively of the systems. The results show a greater corrosive effect of abiotic systems, this indicates a microorganisms protection effect to the metal, opposite to the first hypothesis. This result was ratified observing surface coupons by using Scanning Electron Microscopy (SEM) technique. A possible mechanism based on Evans - Tafel graph is proposed to explain inhibitor microorganism effect. [Spanish] La corrosion microbiologica es un tipo comun de deterioro que afecta diversas industrias, una de ellas es la petrolera en la que se estiman que el 20% o 30% de fallas en las tuberias de trasporte de hidrocarburos es favorecida por microorganismos. Las reacciones quimicas que sustentan estos, generan transferencia de iones, lo que justifica el empleo de tecnicas electroquimicas para su analisis. En este trabajo, se estudiaron probetas de acero de bajo carbono SAE 1018, sumergidas en un medio nutritivo rico en cloruros en presencia y ausencia de tres diferentes cargas microbianas, en tiempos de exposicion de 48 horas y 28 dias. Se realizaron ensayos de resistencia a la polarizacion (Rp) y espectroscopia de impedancia electroquimica (EIS) para determinar el efecto corrosivo de los diferentes sistemas. Los resultados muestran que el medio abiotico causa el mayor efecto corrosivo, lo que indica un efecto protector de los microorganismos al metal contradiciendo la hipotesis inicialmente propuesta. La observacion

  17. Especies forrajeras utilizadas bajo silvo-pastoreo en el centro de Chiapas

    Directory of Open Access Journals (Sweden)

    R. Pinto

    2004-01-01

    Full Text Available Con el objetivo de conocer los usos, la composición química y degradabilidad ruminal de especies arbóreas y herbáceas del trópico mexicano, se desarrolló el presente trabajo en el Valle Central del estado de Chiapas, México. A través de entrevistas con productores se identificaron 14 leñosas y 7 herbáceas con mayor mención forrajera, así como sus múltiples usos. De éstas, el contenido de PC varió de medio a alto (5.8-28.7%, sobresaliendo las especies herbáceas, el contenido de MO fue muy similar entre especies (79.1 96.6% y los niveles más altos de FDN y FDA se encontraron en los frutos y las mayores concentraciones de FT en los follajes arbóreos. En términos de degradabilidad a 24 h de la PC, MS y MO, sobresalieron el follaje de G. americana y el fruto de E. cyclocarpum (P<0.05, en tanto, el follaje y fruto de A. pennatula, y el follaje de B. ungulata y M. hondurana presentaron los valores más bajos (P<0.05 de todas las especies en evaluación. Los parámetros de degradabilidad ruminal (a, b, a+b, c de los frutos fueron menores en comparación a los follajes. Sobresalió el fruto de E. cyclocarpum por su alto potencial de degradabilidad. Para el caso del follaje, excepto el género Acacia, todas las especies presentaron valores altos de degradabilidad ruminal de la MS

  18. El ideal de Yo bajo la tutela del Superyó.

    Directory of Open Access Journals (Sweden)

    María Paulina Mejía.

    1999-01-01

    Full Text Available Este texto se ocupará de analizar la naturaleza y función del Ideal del Yo, así como s relación con la instancia del superyó. Para tal fin se retomará el texto Introducción al Narcisismo, en el cual Freud introduce el Superyó con el nombre de conciencia moral y en el que, a su vez, explica el origen del ideal del Yo como el heredero de la ley y el nacimiento de del “juicio propio”. El ideal del Yo y el Superyó, ambos herederos del Complejo de Edipo, tienen en común que, si bien son resultado de la intervención de la ley y se valen del lenguaje, no se acogen a su estructura y a sus leyes, es decir, que no funcionan con la lógica de la falta y privilegian significantes unarios, que por estar solos no posibilitan la construcción de sentido.En síntesis, este artículo pretende demostrar cómo el Ideal del Yo, bajo la tutela del Superyó, logra darle respuestas al sujeto en relación al ser hombre y ser mujer pero del lado del goce. La lógica que se contrapone a la dimensión del lenguaje y el deseo, los cuales se estructuran a partir de la falta. El ser desde esta dimensión deja de ser una certeza para constituirse en una pregunta

  19. Estimación del tiempo de desarrollo de Lutzomyia evansi bajo condiciones experimentales

    Directory of Open Access Journals (Sweden)

    Claudia Martínez Suárez

    2012-01-01

    Full Text Available Objetivo: Estimar el tiempo promedio de desarrollo de Lutzomyia evansi. Materiales y métodos: Se inició una colonia de Lutzomyia evansi con individuos recolectados en la zona urbana de la ciudad de Sincelejo (Colombia. La colonia fue mantenida en el laboratorio durante tres generaciones filiales bajo condiciones experimentales promedio de 26ºC de temperatura y 94% de humedad relativa. Resultados: La duración del desarrollo de Lutzomyia evansi fue de 36 a 45 días. El tiempo requerido para el desarrollo de los huevos fue en promedio de 6,75 días (rango de 6 a 8 días. La duración en promedio de los diferentes estadios larvales fue 5,75 días en larvas de primer estadio (rango de 5 a 8 días, 5,75 días en larvas de segundo estadio (rango de 4 a 7 días, 5 días en larvas de tercer estadio (rango de 4 a 7 días y 7 días en larvas de cuarto estadio (rango de 6 a 8 días. En la fase de pupa, la duración en promedio fue de 9,75 días (rango de 7 a 17 días. Conclusiones: El tiempo promedio requerido para el desarrollo de Lutzomyia evansi, comprendido desde la alimentación sanguínea de la hembra madre hasta la emergencia del adulto, es de 40 días.

  20. Condiciones de trabajo, fatiga laboral y bajo peso al nacer en vendedoras ambulantes

    Directory of Open Access Journals (Sweden)

    Hernández-Peña Patricia

    1999-01-01

    Full Text Available Objetivo. Este trabajo tipifica las condiciones demográficas, socioeconómicas, laborales, de fatiga laboral y daño reproductivo en una población femenina en edad fértil que trabaja en la venta ambulante en las calles de la Ciudad de México. Material y métodos. Se entrevistaron 426 vendedoras ambulantes. Se describió a la población entrevistada y se exploró la asociación de los componentes de la fatiga laboral con el bajo peso al nacer (BPN mediante regresión logística, en un subgrupo de mujeres que laboraron en la venta ambulante durante su última gestación. Resultados. De las mujeres entrevistadas, 56% realiza jornadas de trabajo superiores a las 48 horas semanales, 87% carece de seguridad social y 68% tiene estudios no mayores de primaria. El riesgo de presentar BPN se eleva cuando se carece de control sobre la cantidad de mercancía a vender (RM 6.5, IC95% 1.3-31, se venden artículos de ocasión como refacciones y ornamentos (RM 6.3, IC95% 1.5-26, se exhibe la mercancía sobre el piso o se carga para su venta (RM 7.7, IC95% 1.8-32, y cuando los recursos para instalar el puesto por primera vez no proceden de la red social de apoyo de la vendedora (RM 7.4, IC95% 1.2-44. Conclusiones. Estos resultados contribuyen a identificar a las vendedoras con mayor riesgo de presentar un hijo con BPN, y sugerir medidas preventivas.

  1. CONTAMINACIÓN DEL SUELO EN LA ZONA MINERA DE RASGATÁ BAJO (TAUSA. MODELO CONCEPTUAL

    Directory of Open Access Journals (Sweden)

    María Eugenia Guerrero Useda

    2016-01-01

    Full Text Available Se desarrolló un modelo conceptual del riesgo de contaminación físico química del suelo en la vereda Rasgatá Bajo. Esta vereda del municipio de Tausa, en Cundinamarca, está en la zona limítrofe del declarado por la Corporación Autónoma Regional de Cundinamarca en 2009, Distrito Regional de Manejo Integrado de los Recursos Naturales Renovables Páramo Guargua y Laguna Verde. La vocación productiva local por tradición ha sido el cultivo de papa (Solanum tuberosum L y la extracción y transformación de arcilla y carbón, actividades con graves impactos sobre el suelo, por lo que el objetivo del proyecto fue identificar y evaluar la condición de este recurso en territorios donde confluyen actividades de extracción y transformación de arcilla y carbón. Se siguió un enfoque metodológico mixto que combinó investigación documental, observaciones in situ y medición de características físico químicas para determinar las fuentes y tipos de contaminantes con riesgo de afectar el suelo aledaño a las faenas mineras y con impactos toxicológicos para las personas, la fauna y la flora. Los datos obtenidos aportarán al rediseño y evaluación de los planes de manejo ambiental local.

  2. Estudio de materiales adsorbentes de bajo costo para remover Cr(VI de efluentes acuosos

    Directory of Open Access Journals (Sweden)

    Claudia Vargas-Niño

    2011-01-01

    Full Text Available El presente estudio muestra el enorme potencial de dos tipos de sólidos diferentes, una alúmina comercial y un material producto del compostaje, en la adsorción/eliminación de Cr(VI en medio acuoso, en concentraciones de metal equivalentes a las halladas en aguas residuales provenientes de industrias en Colombia. Ambos materiales mostraron propiedades importantes para la eliminación de Cr(VI, considerándose de mayor relevancia el compost por ser un material de bajo costo. Se establecieron las condiciones óptimas para la adsorción de cromo sobre alúmina y sobre compost. Para la alúmina: concentración inicial de Cr(VI = 10 mgL-1, volumen de solución por masa de adsorbente = 100 mL/g, pH = 2,0, tiempo de equilibrio = 1 hora, y agitación = 150 rpm. Para el compost: concentración inicial de Cr(VI = 3 mg L-1, volumen de solución por masa de adsorbente = 50 mL/g, pH = 2.5, tiempo de equilibrio = 3 horas, y agitación = 150 rpm. Además, los resultados mostraron que las propiedades de adsorción del compost se pueden mejorar mediante la adición de pequeñas cantidades de alúmina. El estudio permitió seleccionar al compost como un material promisorio para procedimientos de remediación de aguas residuales que contienen cromo (VI dentro de una política de manejo y uso de residuos sólidos con el objeto de minimizar el impacto ambiental de éstos.

  3. Desarrollo post-embrionario de Microcerella acrydiorum (Diptera: Sarcophagidae bajo condiciones de laboratorio

    Directory of Open Access Journals (Sweden)

    Andrea V. DE ARRIBA

    2006-01-01

    Full Text Available Se estudió el desarrollo post-embrionario de Microcerella acrydiorum (Weyenbergh bajo condiciones controladas (temperatura media: 27,50 ± 2,60°C, humedad relativa media: 36,47 ± 8,10% y fotoperíodo artificial: 14 horas luz y se determinaron los siguientes parámetros biológicos: tiempo de desarrollo larval y pupal, período de prelarviposición, supervivencia y razón sexual. El tiempo de desarrollo larval fue de 3,78 ± 0,81 días, el tiempo de desarrollo pupal de 8,63 ± 1,45 días, el período de prelarviposición de 18,25 ± 4,06 días y el ciclo completo fue de 30,66 días. La probabilidad de supervivencia al estado adulto fue de 75,80%. Al menos el 98,73% de las larvas lograron formar el pupario, de estas el 85,81% completó la metamorfosis y transformadas en adultos abandonaron los puparios; sólo el 89,47% de los adultos emergió a la superficie. El estado pupal resultó ser el más susceptible, concentrando casi el 58% de las muertes. La proporción de sexos no se apartó de la relación esperada 1:1 (p > 0,15.

  4. Vivencia infantil del clima de violencia y represión bajo dictadura

    Directory of Open Access Journals (Sweden)

    Salomón Magendzo

    2000-01-01

    Full Text Available Esta investigación parte del supuesto de que el régimen dictatorial chileno no sólo afectó a los niños y niñas cuyos familiares fueron directamente detenidos, torturados y/o desaparecidos, sino también a aquellos que sólo tuvieron que vivir el clima de represión masiva, especialmente en los barrios de bajos recursos. La mayor parte de los jóvenes entrevistados recordaron espontáneamente el clima caracterizado por protestas de la población y represión intensa durante el período 1983-1986. Las entrevistas fueron analizadas a través de un método inductivo, sin categorías preestablecidas. Partiendo del relato de los propios jóvenes sobre su infancia, se identificaron los siguientes ejes que permitieron ordenar la información: la descripción del clima de violencia y represión; el fenómeno de la vivencia emocional de dicho clima como niños y niñas; las reacciones familiares frente al referido clima; la visión de la infancia, la familia y la población que los entrevistados perciben que tuvieron como niños y niñas; las consecuencias del haber vivido en un clima de violencia y represión a nivel personal y social; y la relación de los jóvenes con sus recuerdos, así como la visión actual que tienen de su población. El artículo da cuenta de lo encontrado en los ejes mencionados para luego extenderse a una discusión acerca de los resultados.

  5. Uso eficiente del agua para el cultivo de rosa cv. Freedom bajo invernadero

    Directory of Open Access Journals (Sweden)

    John J. Arévalo-H

    2013-08-01

    Full Text Available Determinar el requerimiento de agua y el momento adecuado de distribución, es un factor fundamental para el cultivo de flores. El objetivo del presente trabajo fue determinar el efecto de la aplicación de tres láminas de riego sobre el desarrollo y producción del cultivo de la Rosa cv. Freedom, bajo invernadero. El experimento se realizó con tres láminas de riego en un cultivo de rosa (Rosa spp. cv. Freedom. Se analizó el crecimiento de los tallos florales, la vida en florero, la producción y la eficiencia en el uso del agua. Los tratamientos se basaron en tres niveles de evapotranspiración de cultivo (ETc (70, 80 y 100%. Durante el estudio, el cultivo se mantuvo en producción constante. Se aplicaron 384,87, 254,25 y 218,97 m³ correspondiente a 100, 80 e 70% de ETc respectivamente, significando un ahorro de agua de 14,0 y 21,8% en el 80 e 70% de ETc respectivamente. El coeficiente de cultivo (Kc vario entre 0,58 y 1,65, con una media de 1,13. No se encontraron diferencias en la producción. Las curvas de crecimiento presentaron incremento continuo, con ajuste al modelo logístico. El 70% de ETc presentó la mayor eficiencia en el uso del agua, con 185 tallos m-3. La conservación media de los tallos florales fue de 12 a 15 días. La mayor causa de pérdida fue la deshidratación, que inició en el día 11, comportamiento normal del tallo floral.

  6. Ethical tensions: A qualitative systematic review of new graduate perceptions.

    Science.gov (United States)

    Hazelwood, Tori; Murray, Carolyn M; Baker, Amy; Stanley, Mandy

    2017-01-01

    New graduate transition into the workforce is challenging and can involve managing ethical tensions. Ethical tensions cause new graduates to doubt their capabilities due to their lack of experience. To support new graduates, we need to know what these ethical tensions are. To explore the ethical tensions perceived to occur in practice for new graduate health professionals. This qualitative systematic review involved a search of five databases (Medline, EMBASE, AMED, CINAHL and Scopus) which resulted in the retrieval of 3554 papers. After the two-phased screening process, eight studies were identified that met the inclusion criteria and had rich data on the review question. Articles were read several times, critically appraised and analysed through thematic analysis. Ethical considerations: No ethical approval was required for the systematic review. The review was conducted following well-established reporting guidelines enabling transparency and rigour. Studies originated from Australia, United States, Iran and China. One study included speech pathologists and seven were with nurses. Four themes included the following: (1) enduring an unknown workplace culture that generates uncertainty without support for new graduates; (2) being vulnerable because of distress from bullying, exclusion and being a scapegoat; (3) constraining systems and institutional restrictions that cause dilemmas; and (4) experiencing disillusionment from lost ideals about ethical practice. This review has brought to light the vulnerability of new graduates to negative workplace culture and collegial incivility. In addition, new graduates are subjected to ethical tensions created by institutional constraints which can create dilemmas and uncertainties through practice that does not align with what they anticipated. Understanding ethical tensions experienced by new graduates enables provision of informed support. There needs to be considerable cultural change for orientation and socialisation of

  7. NOAA ESRI Geotiff - 5m Bathymetry around Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Geotiff with 5 meter cell size representing the bathymetry of selected portions of seafloor around Bajo De Cico in Puerto Rico, derived...

  8. NOAA TIFF Image - 1 m Backscatter Mosaic of Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD83 (NCEI Accession 0131853)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1 meter resolution backscatter mosaic of Bajo de Cico off the coast of western Puerto Rico, collected using a Kongsberg EM 1002 (95 kHz)...

  9. NOAA ESRI Grid - 3m Bathymetry around Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Grid with 3 meter cell size representing the bathymetry of selected portions of seafloor around Bajo De Cico in Puerto Rico, derived...

  10. NOAA ESRI Grid - 5m Bathymetry around Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Grid with 5 meter cell size representing the bathymetry of selected portions of seafloor around Bajo De Cico in Puerto Rico, derived...

  11. NOAA ESRI Geotiff - 3m Bathymetry around Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Geotiff with 3 meter cell size representing the bathymetry of selected portions of seafloor around Bajo De Cico in Puerto Rico, derived...

  12. NOAA ESRI Geotiff - 10m Bathymetry around Bajo de Cico, Puerto Rico, Project NF-07-06, 2007, UTM 19 NAD 83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains an ESRI Geotiff with 10 meter cell size representing the bathymetry of selected portions of seafloor around Bajo De Cico in Puerto Rico,...

  13. Riesgos y consecuencias de las prácticas sexuales en adolescentes bajo los efectos de alcohol y otras drogas

    Directory of Open Access Journals (Sweden)

    Guillermo Castaño Pérez

    2013-03-01

    Full Text Available Introducción: la sexualidad, y el consumo de alcohol y drogas en los adolescentes, figuran en la actualidad como uno de los asuntos con mayor prioridad para la salud pública. La preocupación radica en reducir los riesgos de infecciones de transmisión sexual, el virus de la inmunodeficiencia humana y los embarazos tempranos no deseados. Objetivo: analizar las prácticas sexuales bajo el efecto de alcohol y otras drogas, y los riesgos que esto implica, en los adolescentes de la ciudad de Medellín. Métodos: la muestra se estableció mediante método probabilístico aleatorio y por conglomerados. El universo correspondió al número total de estudiantes matriculados en colegios públicos y privados de la ciudad de Medellín de 8vo., 9no., 10mo. y 11no. grados, en el año 2010 (91 857 estudiantes con edades comprendidas entre los 14 y 17 años. El tamaño muestral incluido fue de 955 estudiantes usando un intervalo de confianza de 95. Se diseñó un estudio descriptivo, transversal para conocer las prácticas sexuales bajo el efecto de alcohol u otras drogas, y los riesgos que corren los adolescentes. Se establecieron frecuencias, porcentajes y asociaciones estadísticas con el programa SPSS, versión 19.0 Resultados: consumir alcohol u otras drogas y tener prácticas sexuales presenta una asociación estadística significativa (p= 0,000. El 62,4 % de los adolescentes que han consumido una sustancia psicoactiva, han tenido relaciones sexuales, frente a un 29,4 % que, habiendo consumido alcohol y otras drogas, no lo han hecho. El alcohol es la droga más usada (79,8 %. Le siguen la marihuana (31,83 %, poppers (8,97 %, la cocaína (7,75 % y el éxtasis (5,71 %. Las prácticas sexuales más frecuentes bajo el efecto de sustancias psicoactivas son las exploratorias (manoseo, caricias, para un 71,02 %, seguida de la penetrativa vaginal (63,67 %, el sexo oral (45,30 % y la masturbación (19,59 %. De los adolescentes que tienen prácticas sexuales (N

  14. Prediction of tension-type headache risk in adolescents

    Directory of Open Access Journals (Sweden)

    K. A. Stepanchenko

    2016-08-01

    Full Text Available Tension-type headache is the actual problem of adolescent neurology, which is associated with the prevalence of the disease, the tendency of the disease to the chronic course and a negative impact on performance in education, work capacity and quality of patients’ life. The aim. To develop a method for prediction of tension-type headache occurrence in adolescents. Materials and methods. 2342 adolescent boys and girls at the age of 13-17 years in schools of Kharkiv were examined. We used questionnaire to identify the headache. A group of adolescents with tension-type headache - 1430 people (61.1% was selected. The control group included 246 healthy adolescents. Possible risk factors for tension-type headache formation were divided into 4 groups: genetic, biomedical, psychosocial and social. Mathematical prediction of tension-type headache risk in adolescents was performed using the method of intensive indicators normalization of E.N. Shigan, which was based on probabilistic Bayesian’s method. The result was presented in the form of prognostic coefficients. Results. The most informative risk factors for tension-type headache development were the diseases, from which the teenager suffered after 1 year (sleep disorders, gastrointestinal diseases, autonomic disorders in the family history, traumatic brain injury, physical inactivity, poor adaptation of the patient in the kindergarten and school, stresses. Diagnostic scale has been developed to predict the risk of tension-type headache. It includes 23 prognostic factors with their gradation and meaning of integrated risk indicator, depending on individual factor strength influence. The risk of tension-type headache development ranged from 25,27 to 81,43 values of prognostic coefficient (low probability (25,27-43,99, the average probability (43,99-62,71 and high probability (62,71- 81,43. Conclusion. The study of tension-type headache risk factors, which were obtained by using an assessed and

  15. Exploring the tensions of being and becoming a medical educator.

    Science.gov (United States)

    Sethi, Ahsan; Ajjawi, Rola; McAleer, Sean; Schofield, Susie

    2017-03-23

    Previous studies have identified tensions medical faculty encounter in their roles but not specifically those with a qualification in medical education. It is likely that those with postgraduate qualifications may face additional tensions (i.e., internal or external conflicts or concerns) from differentiation by others, greater responsibilities and translational work against the status quo. This study explores the complex and multi-faceted tensions of educators with qualifications in medical education at various stages in their career. The data described were collected in 2013-14 as part of a larger, three-phase mixed-methods research study employing a constructivist grounded theory analytic approach to understand identity formation among medical educators. The over-arching theoretical framework for the study was Communities of Practice. Thirty-six educators who had undertaken or were undertaking a postgraduate qualification in medical education took part in semi-structured interviews. Participants expressed multiple tensions associated with both becoming and being a healthcare educator. Educational roles had to be juggled with clinical work, challenging their work-life balance. Medical education was regarded as having lower prestige, and therefore pay, than other healthcare career tracks. Medical education is a vast speciality, making it difficult as a generalist to keep up-to-date in all its areas. Interestingly, the graduates with extensive experience in education reported no fears, rather asserting that the qualification gave them job variety. This is the first detailed study exploring the tensions of educators with postgraduate qualifications in medical education. It complements and extends the findings of the previous studies by identifying tensions common as well as specific to active students and graduates. These tensions may lead to detachment, cynicism and a weak sense of identity among healthcare educators. Postgraduate programmes in medical education

  16. Caregiving, perceptions of maternal favoritism, and tension among siblings.

    Science.gov (United States)

    Suitor, J Jill; Gilligan, Megan; Johnson, Kaitlin; Pillemer, Karl

    2014-08-01

    Studies of later-life families have revealed that sibling tension often increases in response to parents' need for care. Both theory and research on within-family differences suggest that when parents' health declines, sibling relations may be affected by which children assume care and whether siblings perceive that the parent favors some offspring over others. In the present study, we explore the ways in which these factors shape sibling tension both independently and in combination during caregiving. In this article, we use data collected from 450 adult children nested within 214 later-life families in which the offspring reported that their mothers needed care within 2 years prior to the interview. Multilevel analyses demonstrated that providing care and perceiving favoritism regarding future caregiving were associated with sibling tension following mothers' major health events. Further, the effects of caregiving on sibling tension were greater when perceptions of favoritism were also present. These findings shed new light on the conditions under which adult children are likely to experience high levels of sibling tension during caregiving. Understanding these processes is important because siblings are typically the individuals to whom caregivers are most likely to turn for support when assuming care of older parents, yet these relationships are often a major source of interpersonal stress. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Effects of surface tension on tray point efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G.X.; Afacan, A.; Chuang, K.T. (Alberta Univ., Edmonton, AB (Canada))

    1994-08-01

    Sieve tray efficiencies for the distillation of methanol/water, acetic acid/water, and cyclohexane/n-heptane mixtures were measured as a function of composition under fixed vapor and liquid rates in a 0.15 m diameter distillation column. The three binary distillation systems used in the study had a wide range of surface tensions measured as a function of composition. From the efficiencies measured, the number of vapor- and liquid-phase transfer units (Ng and Nl) was determined and the effects of surface tension on Ng and Nl were identified. To further verify the results obtained from the distillation column, bubble sizes in froths for air/water, air/methanol, and air/(water + surfactant) systems with different surface tensions were measured. The results show that surface tension has a significant effect on tray efficiency and the number of transfer units. Bubble sizes in the tray froths were mainly determined by surface tension, and bubble breakup and coalescence occur in the froths. 45 refs., 15 figs., 1 tab.

  18. A density gradient theory based method for surface tension calculations

    DEFF Research Database (Denmark)

    Liang, Xiaodong; Michelsen, Michael Locht; Kontogeorgis, Georgios

    2016-01-01

    The density gradient theory has been becoming a widely used framework for calculating surface tension, within which the same equation of state is used for the interface and bulk phases, because it is a theoretically sound, consistent and computationally affordable approach. Based on the observation...... that the optimal density path from the geometric mean density gradient theory passes the saddle point of the tangent plane distance to the bulk phases, we propose to estimate surface tension with an approximate density path profile that goes through this saddle point. The linear density gradient theory, which...... assumes linearly distributed densities between the two bulk phases, has also been investigated. Numerical problems do not occur with these density path profiles. These two approximation methods together with the full density gradient theory have been used to calculate the surface tension of various...

  19. Tension stiffening in partially prestressed concrete flexural members

    International Nuclear Information System (INIS)

    Oukaili, K. N.

    2000-01-01

    Concrete tensile strength is not being zero, cracking does not extend to the neutral axis as assumed in standard cracked section analysis. In addition, un cracked concrete, which exists above the crack tip in the tension zone, contributes to the stiffness of the member. This paper discusses the influence of concrete tensile stress below the neut ural axis position at the cracked section on the tension stiffening phenomenon and deflection of progressively cracking partially prestressed concrete flexural members. The computation of the neutral axis location, which takes into consideration the effect of concrete in tension, can be achieved by solving iteratively tow simultaneous equation derived from forces and moments equilibrium, strain compatibility and linear stress - strain relationship in concrete across the section depth. Once the section depth after cracking is known, it can be used to calculate the effective moment of inertia for deflection analysis. (author). 13 refs., 3 figs., 1 table

  20. Tensile behavior and tension stiffening of reinforced concrete

    International Nuclear Information System (INIS)

    Choun, Young Sun; Seo, Jeong Moon

    2001-03-01

    For the ultimate behavior analysis of containment buildings under severe accident conditions, a clear understanding of tensile behaviors of plain and reinforced concrete is necessary. Nonlinear models for tensile behaviors of concrete are also needed. This report describe following items: tensile behaviors of plain concrete, test results of reinforced concrete panels in uniaxial and biaxial tension, tension stiffening. The tensile behaviors of reinforced concrete are significantly influenced by the properties of concrete and reinforcing steel. Thus, for a more reliable evaluation of tensile behavior and ultimate pressure capacity of a reinforced or prestressed concrete containment building, an advanced concrete model which can be considered rebar-concrete interaction effects should be developed. In additions, a crack behavior analysis method and tension stiffening models, which are based on fracture mechanics, should be developed. The model should be based on the various test data from specimens considering material and sectional properties of the containment building

  1. Modeling of surface tension effects in venturi scrubbing

    Science.gov (United States)

    Ott, Robert M.; Wu, Tatsu K. L.; Crowder, Jerry W.

    A modified model of venturi scrubber performance has been developed that addresses two effects of liquid surface tension: its effect on droplet size and its effect on particle penetration into the droplet. The predictions of the model indicate that, in general, collection efficiency increases with a decrease in liquid surface tension, but the range over which this increase is significant depends on the particle size and on the scrubber operating parameters. The predictions further indicate that the increases in collection efficiency are almost totally due to the effect of liquid surface tension on the mean droplet size, and that the collection efficiency is not significantly affected by the ability of the particle to penetrate the droplet.

  2. Uniaxial Tension Test of Slender Reinforced Early Age Concrete Members

    Directory of Open Access Journals (Sweden)

    Wenbo Zhang

    2011-08-01

    Full Text Available The present study aims to obtain the tensile properties of early age concrete based on a uniaxial tension test employing RC slender members. First, the paper shows that concrete strain is equal to the strain of rebar at the mid-span of the RC member. The tensile Young’s modulus and the strain capacity of early age concrete are estimated using strain measurements. The experiment indicated that the tensile Young’s modulus at an early age is higher than the compressive modulus. This observation was similar to one found in a previous investigation which used a direct tension test of early age concrete. Moreover, the paper describes how an empirical equation for mature concrete can be applied to the relation between uniaxial tensile strength and splitting tensile strength even in early age concrete. Based on a uniaxial tension test, the paper proposes an empirical equation for the relationship between standard bond stresses and relative slip.

  3. Changing market values? Tensions of contradicting public management discourses

    DEFF Research Database (Denmark)

    Plotnikof, Mie

    2016-01-01

    that the discursive tensions between such value-laden practices indicate a changing marketization associated with collaboration and trust, yet also competition. Research limitations/implications To research it becomes critical to advance theoretical and empirical knowledge on the constitutive effects of such complex......The purpose of this paper is to address studies of New Public Governance (NPG) as a post-New Public Management (NPM) tendency. Although NPG is considered a contrast to NPM and its market incentives, it argues that the practices emerging in tensions of NPM and NPG discourses indicate not a clear......-cut shift away from NPM, but rather changes that combine competition with collaboration and trust. Design/methodology/approach It offers a discourse approach to advance the theorizing and empirical unfolding of the tensions of contradicting, yet co-existing discourses of NPM and NPG and their effects...

  4. Surface tension and density of Si-Ge melts

    Science.gov (United States)

    Ricci, Enrica; Amore, Stefano; Giuranno, Donatella; Novakovic, Rada; Tuissi, Ausonio; Sobczak, Natalia; Nowak, Rafal; Korpala, Bartłomiej; Bruzda, Grzegorz

    2014-06-01

    In this work, the surface tension and density of Si-Ge liquid alloys were determined by the pendant drop method. Over the range of measurements, both properties show a linear temperature dependence and a nonlinear concentration dependence. Indeed, the density decreases with increasing silicon content exhibiting positive deviation from ideality, while the surface tension increases and deviates negatively with respect to the ideal solution model. Taking into account the Si-Ge phase diagram, a simple lens type, the surface tension behavior of the Si-Ge liquid alloys was analyzed in the framework of the Quasi-Chemical Approximation for the Regular Solutions model. The new experimental results were compared with a few data available in the literature, obtained by the containerless method.

  5. Resistance to small plastic strains during martensite tempering under tension

    Energy Technology Data Exchange (ETDEWEB)

    Zabil' skij, V.V.; Sarrak, V.I. (AN SSSR, Sverdlovsk. Inst. Fiziki Metallov)

    1982-11-01

    The mechanism of plastic deformation of martensite of a series of hardened steels (N18, 20KhG, 50KhFA and others) during tempering under tension and the role of residual internal microstresses and phase transformations are studied. It is shown that martensite low resistance to small plastic deformations during tempering under tension which is usually associated with phase transformations depends as well on the level of residual internal microstresses in the martensite structure. The decrease of resistance to deformation in the course of the decomposition of a solid solution is due to weakening of martensitic matrix because of carbon departure from the solid solution and carbide coarsening. An assumption is made that martensite plastic deformation during tempering under tension is realized at the expense of the directed microplastic deformation in the regions of higher concentration of internal stresses.

  6. Surface tension in microsystems engineering below the capillary length

    CERN Document Server

    Lambert, Pierre

    2014-01-01

    This book describes how surface tension effects can be used by engineers to provide mechanical functions in miniaturized products (<1 mm). Even if precursors of this field such as Jurin or Laplace already date back to the 18th century, describing surface tension effects from a mechanical perspective is very recent. The originality of this book is to consider the effects of capillary bridges on solids, including forces and torques exerted both statically and dynamically by the liquid along the 6 degrees-of-freedom. It provides a comprehensive approach to various applications, such as capillary adhesion (axial force), centering force in packaging and micro-assembly (lateral force) and recent developments such as a capillary motor (torque). It devises how surface tension can be used to provide mechanical functions such as actuation (bubble-actuated compliant table), sealing and tightness, energy harvesting, nanodispending.

  7. Actividad enzimática del suelo -Deshidrogenasa , -ß Glucosidasa , Fosfatasa y Ureasa - bajo diferentes cultivos.

    Directory of Open Access Journals (Sweden)

    Carlos Henríquez

    2014-01-01

    Full Text Available Se analizó la actividad de 4 enzimas del suelo en fincas bajo diferentes manejos agronómi - cos y en diferentes tipos de suelos. Las enzimas evaluadas fueron la Fosfatasa, β-Glucosidasa, Deshidrogenasa y Ureasa. Se tomaron muestras de suelo de los primeros 20 cm de profundidad con el fin de analizarlas químicamente y determinar la actividad de las 4 enzimas a evaluar. Se encontró que la actividad de la Deshidrogenasa varió de 0,13 a 4,46 con un promedio de 1,17 (μg INTF.g - 1 .h -1 ; la β-Glucosidasa varió de 31,9 a 208,1 con un promedio de 108,1 (μg PNP.g -1 .h -1 . Por otro lado la Fosfatasa tuvo valores entre 413,4 y 3043,6 con un promedio de 1521,5 μg PNP.g -1 .h -1 , mientras que la Ureasa varió de 12,5 a 52,8 con un promedio de 38,3 μg N-NH4.g -1 .h -1 . La Fos - fatasa correlacionó con el porcentaje de materia orgánica y de carbono en el suelo (0,75 y 0,76 respectivamente, p<0,01; se encontró una rela - ción inversa entre la actividad de esta enzima y el contenido de P disponible (r de -0,53, p<0,10. La Ureasa correlacionó con la Fosfatasa (r de 0,61 p<0,05 y con la Deshidrogenasa (r de -0,77 p<0,01. El análisis multivariado de conglomera - dos a partir de la actividad enzimática permitió hacer grupos similares según el tipo de cultivo, lo que evidencia el potencial de utilización que tiene esta propiedad para realizar estudios más detallados.

  8. Viabilidad de Saccharomyces boullardii en queso fresco bajo condiciones de acidez “in vitro”

    Directory of Open Access Journals (Sweden)

    Rafael Zamora-Vega

    2015-01-01

    Full Text Available Un alimento funcional contiene en su formulación una o más sustancias que generan bienestar a la salud humana como son probióticos, prebióticos y ácidos grasos, entre otros. En los alimentos funcionales los microorganismos probióticos deben permanecer viables y activos en el alimento y durante el pasaje gastrointestinal, para garantizar su potencial efecto benéfico en el huésped. En el presente estudio se evaluó la viabilidad de la levadura probiótica Saccharomyces boulardii tanto de forma libre como encapsulada bajo condiciones de acidez, adaptada a un queso fresco. Método: La levadura fue expuesta en el alimento tanto en forma libre como encapsulada. Los materiales usados para encapsular fueron una mezcla de alginato de sodio, inulina y mucílago de nopal (Opuntia ficus-indica. Para la liberación del microorganismo, el estudio se realizó a pH de 2.0 y 6.5, simulándose las condiciones de acidez de estómago y colon respectivamente, a diferentes tiempos de exposición de 0, 60, 120 y 180 min. Resultados: A pH de 2.0 se observó mayor pérdida en la viabilidad del probiótico en forma libre, la cual fue de 23.72, 27.03 y 33.02 % respectivamente, con respecto a la viabilidad inicial; cuando el microorganismo se adicionó al queso en forma encapsulada, su pérdida de viabilidad a los mismos tiempos de exposición fue de 5.74, 14.24 y 18.81%, manteniendo mayor supervivencia. Por otra parte, a pH de 6.5 el probiótico libre en el alimento mostró una pérdida de viabilidad de 2.23, 3.50 y 5.94%, en cambio de forma encapsulada la pérdida de viabilidad fue de 0.95, 2.20 y 3.03%, respectivamente, observándose mayor supervivencia que en estado libre. Conclusión: El queso fresco mantuvo viable el nivel de supervivencia de Saccharomyces boulardii, particularmente cuando fue adicionado en forma encapsulada comparado a cuando fue incorporado en estado libre.

  9. La Frontera como Recurso Turístico. Posibilidades del Bajo/Baixo Guadiana

    Directory of Open Access Journals (Sweden)

    José Manuel Jurado-Almonte

    2018-02-01

    Full Text Available En el espacio de integración de la Unión Europea persisten las fronteras, ya sin las dificultades y barreras de antaño, pero manteniendo numerosos símbolos y elementos del patrimonio cultural que siguen marcando una diferencia. Son líneas divisorias y, a la vez, franjas de territorios de transición con un importante patrimonio natural y cultural que se convierten ahora en recursos de atracción para novedosas demandas turísticas. Por ello, se estudia ya el turismo de frontera como un nuevo producto donde el recurso de la frontera y la historia es el principal atractivo y destino, aunque de forma complementaria a otros recursos y productos turísticos. Al margen de otros territorios y destinos fronterizos de Europa o del mundo, nuestra preocupación investigadora se centra en la Raya luso-española, en su extremo sur, en el Bajo Guadiana, en espacios que participan del Algarve, Baixo Alentejo y Huelva. En este territorio se conjugan destinos turísticos consolidados (Algarve y Costa Occidental de Huelva con un interior muy próximo e ignoto para la mayor parte de los turistas alojados en ese borde costero, a apenas unas decenas de kilómetros. Sin embargo, en los últimos años, un incipiente espacio turístico parece abrirse tierras adentro (y aguas desde la costa. El estuario del Guadiana actúa de puerta de entradahacia un interior rico en recursos y patrimonios histórico-artísticos y naturales y que podría favorecerse de un turismo de frontera. Nuestra hipótesis principal es que el desarrollo del turismo de frontera podría ser una oportunidad para este territorio transfronterizo. En este trabajo tratamos, por tanto, de: -\tAnalizar el marco geográfico y el patrimonio natural y cultural de este ámbito transfronterizo, con una breve semblanza a su población y políticas de cooperación en materia de infraestructuras de accesibilidad y de turismo. -\tdiagnosticar este novedoso producto turístico y para este territorio en

  10. Mecanismo de acción de las fosfatasas ácidas de bajo peso molecular

    Directory of Open Access Journals (Sweden)

    Emilio Guija

    2007-12-01

    Full Text Available Las fosfatasas ácidas son enzimas ampliamente distribuidas en la naturaleza y tienen la propiedad de hidrolizar fosfomonoésteres a pH 5,0, liberando como productos de la reacción un alcohol y fosfato inorgánico. Cuando se compara los valores de kcat/Km de las fosfatasas de hígado, de bovino, alpaca y porcino, nos permite sugerir que estas enzimas tienen elevada afinidad por el sustrato p-nitrofenil fosfato. Los productos que se liberan durante la catálisis por fosfatasa ácida, muestran que el fenol o el p-nitrofenol se comportan como inhibidores de tipo no competitivo, mientras que el fosfato inorgánico muestra una inhibición de tipo competitiva. Para evidenciar la probable formación de un complejo covalente en la secuencia catalítica, se utilizó diversos nucleófilos más eficientes que el agua, tales como metanol, etanol y glicerol. Las modificaciones que produjeron en los valores Km, Vmax y los productos liberados en la reacción sugieren la formación de un complejo enzima-fosfato. El pH afecta los valores de Km y Vmax de las fosfatasas ácidas, un análisis del comportamiento de estas enzimas en un rango de pH comprendido entre 3,8 y 6,8 sugieren que en el sitio activo existe un residuo de aminoácido con un valor pKa de 6,0. El uso del dietilpirocarbonato, un compuesto que selectivamente reacciona con el residuo histidina en las proteínas, inhibe completamente a estas fosfatasas. Así mismo, un experimento de cinética de inhibición múltiple realizado en presencia de fosfato inorgánico y dietilpirocarbonato permite calcular un valor Ki que es igual al obtenido en otras condiciones experimentales. En tal sentido, las fosfatasas ácidas de bajo peso molecular catalizarían las reacciones a través de un modelo de tipo uni biordenado, con la formación de un complejo covalente intermedio, y que el residuo histidina participaría directamente en la catálisis.

  11. La importancia de los materiales en las viviendas de muy bajo coste

    Directory of Open Access Journals (Sweden)

    Salas, Julián

    1992-09-01

    Full Text Available This text fits into the context of the attempt to emphasize the considerable importance of the factor of the construction materials in the subsection of low cost housing in Developing Countries in general and in Latín America in particular. The author tries to quantify, in a global manner, the repercussion of the materials through different assumptions and to show how it increases as the sections of installations and finishes diminish —in fact, practically disappear—. In accordance with this and as a consequence, the author discusses the necessity to use autochthonous materials and to support the research and technological development which lay stress on the use of alternative materials and the re-use of agro-industrial waste. As a pan of the Chapter V reproduced here, a special Section entitled "The Industry of Construction Materials" is contemplated, a section which we omitted and which can be found in n.º 198 of this Quarterly where it was originally published.

    El texto que sigue se encuadra en el contexto de intentar enmarcar la importancia considerable del capítulo de los materiales de construcción en el subsector de las viviendas de muy bajo coste en los Países en Vías de Desarrollo en general, y en Latinoamérica en particular. El autor trata de cuantificar, en forma global, la repercusión de los materiales en varios supuestos y como ésta aumenta al disminuir —prácticamente desaparecer— las partidas de instalaciones y acabados. De conformidad y como consecuencia de lo anterior, el autor se ocupa de la necesidad de emplear materiales autóctonos y de apoyar la investigación y el desarrollo tecnológico que ponen énfasis en la utilización de materiales alternativos y la reutilización de desechos agro-industriales. Formando parte del Capítulo V que se reproduce, se contempla un apartado específico con el título "La Industria de Materiales de la Construcción" que hemos omitido, remitiendo al lector

  12. Contact Angles and Surface Tension of Germanium-Silicon Melts

    Science.gov (United States)

    Croell, A.; Kaiser, N.; Cobb, S.; Szofran, F. R.; Volz, M.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Precise knowledge of material parameters is more and more important for improving crystal growth processes. Two important parameters are the contact (wetting) angle and the surface tension, determining meniscus shapes and surface-tension driven flows in a variety of methods (Czochralski, EFG, floating-zone, detached Bridgman growth). The sessile drop technique allows the measurement of both parameters simultaneously and has been used to measure the contact angles and the surface tension of Ge(1-x)Si(x) (0 less than or equal to x less than or equal to 1.3) alloys on various substrate materials. Fused quartz, Sapphire, glassy carbon, graphite, SiC, carbon-based aerogel, pyrolytic boron nitride (pBN), AIN, Si3N4, and polycrystalline CVD diamond were used as substrate materials. In addition, the effect of different cleaning procedures and surface treatments on the wetting behavior were investigated. Measurements were performed both under dynamic vacuum and gas atmospheres (argon or forming gas), with temperatures up to 1100 C. In some experiments, the sample was processed for longer times, up to a week, to investigate any changes of the contact angle and/or surface tension due to slow reactions with the substrate. For pure Ge, stable contact angles were found for carbon-based substrates and for pBN, for Ge(1-x)Si(x) only for pBN. The highest wetting angles were found for pBN substrates with angles around 170deg. For the surface tension of Ge, the most reliable values resulted in gamma(T) = (591- 0.077 (T-T(sub m)) 10(exp -3)N/m. The temperature dependence of the surface tension showed similar values for Ge(1-x)Si(x), around -0.08 x 10(exp -3)N/m K, and a compositional dependence of 2.2 x 10(exp -3)N/m at%Si.

  13. A microfluidic cell culture array with various oxygen tensions.

    Science.gov (United States)

    Peng, Chien-Chung; Liao, Wei-Hao; Chen, Ying-Hua; Wu, Chueh-Yu; Tung, Yi-Chung

    2013-08-21

    Oxygen tension plays an important role in regulating various cellular functions in both normal physiology and disease states. Therefore, drug testing using conventional in vitro cell models under normoxia often possesses limited prediction capability. A traditional method of setting an oxygen tension in a liquid medium is by saturating it with a gas mixture at the desired level of oxygen, which requires bulky gas cylinders, sophisticated control, and tedious interconnections. Moreover, only a single oxygen tension can be tested at the same time. In this paper, we develop a microfluidic cell culture array platform capable of performing cell culture and drug testing under various oxygen tensions simultaneously. The device is fabricated using an elastomeric material, polydimethylsiloxane (PDMS) and the well-developed multi-layer soft lithography (MSL) technique. The prototype device has 4 × 4 wells, arranged in the same dimensions as a conventional 96-well plate, for cell culture. The oxygen tensions are controlled by spatially confined oxygen scavenging chemical reactions underneath the wells using microfluidics. The platform takes advantage of microfluidic phenomena while exhibiting the combinatorial diversities achieved by microarrays. Importantly, the platform is compatible with existing cell incubators and high-throughput instruments (liquid handling systems and plate readers) for cost-effective setup and straightforward operation. Utilizing the developed platform, we successfully perform drug testing using an anti-cancer drug, triapazamine (TPZ), on adenocarcinomic human alveolar basal epithelial cell line (A549) under three oxygen tensions ranging from 1.4% to normoxia. The developed platform is promising to provide a more meaningful in vitro cell model for various biomedical applications while maintaining desired high throughput capabilities.

  14. PAX RUSSICA: AMBIGÜEDAD GEOPOLÍTICA DE LAS TENSIONES Y CONFLICTOS EN EL ESPACIO DE LA ANTIGUA UNIÓN SOVIÉTICA

    Directory of Open Access Journals (Sweden)

    Silvia Marcu

    2011-01-01

    Full Text Available Una de las herencias de los últimos años del comunismo en la Unión Soviética (URSS, para la nueva Rusia, consistió en los conflictos de naturaleza étnica o confesional que estallaron cuando la opresión política del régimen dejó de paralizar el espíritu nacional. Los mismos entraron en el diccionario geopolítico postsoviético bajo la denominación de tensiones permanentes y "conflictos congelados" - frozen conflicts; su análisis parte de la idea de que sus premisas están en el pasado, y que el régimen comunista los "congeló" a través del terror dispersado a la escala de la sociedad, sin conseguir alguna vez resolverlos. El artículo presenta el laberinto de las tensiones y de los conflictos generados por la mezcla de naciones, etnias, y por la intensa fragmentación vivida en el espacio postsoviético después de la caída de la URSS. La primera parte presenta los factores condicionantes que desencadenaron dichos conflictos y tensiones, mientras que la segunda y tercera parte intentan realizar una breve síntesis de los focos más importantes donde los mismos se produjeron. Las conclusiones apuntan sobre el papel de Rusia como potencia y su influencia en la región.

  15. Surface tension alteration on calcite, induced by ion substitution

    DEFF Research Database (Denmark)

    Sakuma, Hiroshi; Andersson, Martin Peter; Bechgaard, Klaus

    2014-01-01

    The interaction of water and organic molecules with mineral surfaces controls many processes in nature and industry. The thermodynamic property, surface tension, is usually determined from the contact angle between phases, but how does one understand the concept of surface tension at the nanoscale...... preferentially as ion pairs at solution-calcite interfaces. Mg2+ incorporation weakens organic molecule adhesion while strengthening water adsorption so Mg2+ substitution renders calcite more water wet. When Mg2+ replaces 10% of surface Ca2+, the contact angle changes dramatically, by 40 to 70, converting...

  16. Patient goals after tension free vaginal tape operation

    DEFF Research Database (Denmark)

    Glavind, Karin; Bjørk, Jonna; Kousgaard, Sabrina Just

    INTRODUCTION: This prospective study investigates sexual function in women after a tension-free vaginal tape (TVT) operation and compares short-term and long-term effects. METHODS: Sixty-three women had a TVT operation performed at Aalborg University Hospital, Department of Gynecology and Obstetr......INTRODUCTION: This prospective study investigates sexual function in women after a tension-free vaginal tape (TVT) operation and compares short-term and long-term effects. METHODS: Sixty-three women had a TVT operation performed at Aalborg University Hospital, Department of Gynecology...

  17. Globalization, financial capitalism, and corporate social responsibility: Structural tensions

    Directory of Open Access Journals (Sweden)

    David Barbosa Ramírez

    2014-12-01

    Full Text Available Globalization and financial capitalism keep a synergy in a global context whose problems such as environmental degradation, social inequity, economic crises and corruption are intensified. Corporate Social Responsibility emerges as a mechanism that seeks to mitigate some of these problems, although its effectiveness and impact today are challenged. The system which globalization, financial capitalism and social responsibility are a part of, is currently facing a number of structural tensions that contribute to the analysis, understanding and solving of the mentioned problems. This paper identifies and analyzes four of the aforementioned structural tensions.

  18. How to simulate global cosmic strings with large string tension

    Energy Technology Data Exchange (ETDEWEB)

    Klaer, Vincent B.; Moore, Guy D., E-mail: vklaer@theorie.ikp.physik.tu-darmstadt.de, E-mail: guy.moore@physik.tu-darmstadt.de [Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 2, Darmstadt, D-64289 Germany (Germany)

    2017-10-01

    Global string networks may be relevant in axion production in the early Universe, as well as other cosmological scenarios. Such networks contain a large hierarchy of scales between the string core scale and the Hubble scale, ln( f {sub a} / H ) ∼ 70, which influences the network dynamics by giving the strings large tensions T ≅ π f {sub a} {sup 2} ln( f {sub a} / H ). We present a new numerical approach to simulate such global string networks, capturing the tension without an exponentially large lattice.

  19. Phenylephrine Decreases Vascular Tension in Goat Arteries in Specific Circumstances.

    Directory of Open Access Journals (Sweden)

    Renu R Raj

    Full Text Available Phenylephrine (PE causes vasoconstriction through alpha adrenergic receptors. PE-induced vasodilatation has also been reported earlier in pre-constricted vessels. Here we demonstrate in spiral strips of goat arteries that addition of PE can decrease tone even from base-line levels (i.e. not pre-constricted and show that this process requires nitric oxide (NO and alpha adrenergic stimulation, but is cGMP-independent. Under control conditions, PE caused vasoconstriction, but under conditions where NO levels are higher, as with L-Arginine or sodium nitroprusside, PE decreased vessel tension. L-Arginine/PE combination was not able to decrease tension when alpha adrenoceptors were blocked with Phentolamine or endothelial nitric oxide synthase (eNOS was blocked with Nω-Nitro-L-arginine (L-NNA. Propranolol, a beta blocker, was unable to prevent the reduction in tension by the L-Arginine/PE combination. Adrenaline and noradrenaline (and not isoproterenol also reduced vessel tension in the presence of L-Arginine. Even when NO levels were not enhanced, relieving NO from having to stimulate the enzyme soluble guanylyl cyclase (sGC (either by using sGC blockers, namely ODQ or methylene blue, or by enhancing cGMP levels (with sildenafil which by negative feedback probably inhibits sGC led to PE-induced reduction of vascular tension. PMA-phorbol myristate acetate-an agonist which stimulates Protein Kinase C was able to prevent the ability of PE to reduce vascular tension in a high NO environment. Our conclusion is that PE reduces vascular tension through alpha adrenoceptors if there is excess NO availability to activate a putative pathway. Though the reduction of vessel tone by PE is dependent on NO, it is independent of cGMP. Prior treatment with PMA or PE itself can prevent further PE-induced reduction of tension in a high NO environment. The results here suggest, counter-intuitively, that alpha blockers may be of help in the treatment of septic shock

  20. Tension-induced vesicle fusion: pathways and pore dynamics

    DEFF Research Database (Denmark)

    Shillcock, Julian C.

    2008-01-01

    and eventually opens a pore to complete the fusion process. In pathway II, at higher tension, a stalk is formed during the fusion process that is then transformed by transmembrane pore formation into a fusion pore. Whereas the latter pathway II resembles stalk pathways as observed in other simulation studies......, fusion pathway I, which does not involve any stalk formation, has not been described previously to the best of our knowledge. A statistical analysis of the various processes shows that fusion is the dominant pathway for releasing the tension of the vesicles. The functional dependence of the observed...

  1. Infinite tension limit of the pure spinor superstring

    Energy Technology Data Exchange (ETDEWEB)

    Berkovits, Nathan [ICTP South American Institute for Fundamental Research,Instituto de Física Teórica, UNESP - Univ. Estadual Paulista,Rua Dr. Bento T. Ferraz 271, 01140-070, São Paulo, SP (Brazil)

    2014-03-04

    Mason and Skinner recently constructed a chiral infinite tension limit of the Ramond-Neveu-Schwarz superstring which was shown to compute the Cachazo-He-Yuan formulae for tree-level d=10 Yang-Mills amplitudes and the NS-NS sector of tree-level d=10 supergravity amplitudes. In this letter, their chiral infinite tension limit is generalized to the pure spinor superstring which computes a d=10 superspace version of the Cachazo-He-Yuan formulae for tree-level d=10 super-Yang-Mills and supergravity amplitudes.

  2. Surface tension mediated conversion of light to work

    Science.gov (United States)

    Okawa, David; Pastine, Stefan J; Zettl, Alexander K; Frechet, Jean M. J

    2014-12-02

    Disclosed are a method and apparatus for converting light energy to mechanical energy by modification of surface tension on a supporting fluid. The apparatus comprises an object which may be formed as a composite object comprising a support matrix and a highly light absorptive material. The support matrix may comprise a silicon polymer. The highly light absorptive material may comprise vertically aligned carbon nanotubes (VANTs) embedded in the support matrix. The composite object is supported on a fluid. By exposing the highly light absorptive material to light, heat is generated, which changes the surface tension of the composite object, causing it to move physically within the fluid.

  3. [Delayed (tension) pneumothorax after placement of a central venous catheter].

    Science.gov (United States)

    Tan, E C; van der Vliet, J A

    1999-09-11

    Laborious attempts at introducing a central venous catheter for parenteral nutrition in two women, aged 36 and 62 years, were followed by shortness of breath after 32 and 10 hours, respectively. This symptom was due to a (tension) pneumothorax not visible on earlier roentgenograms. Thoracic drainage led to recovery. In all patients with a central venous catheter an undetected delayed pneumothorax can be present. Urgent chest X-ray examination should be performed in all patients with acute respiratory symptoms. Patients undergoing elective intubation with positive pressure breathing should be examined carefully, since they are at risk of developing a late (tension) pneumothorax.

  4. Tensions of Health: Narratives of Employee Wellness Program Participants.

    Science.gov (United States)

    Tang, Lu; Baker, Jane S; Meadows, Cui Zhang

    2016-09-01

    This article examines dialectical tensions in the health narratives of participants of the Employee Wellness Program (EWP) of a large public university in the southeastern United States. Semi-structured interviews (n = 12) with team leaders in the program indicated that health is a multifaceted concept characterized by three pairs of dialectical tensions: autonomy versus connection, private versus public, and control versus lack of control. These findings suggest that to better promote health and wellness in the workplace, EWP staff should consider employees' unique experiences and beliefs about health when designing organization-wide programs and campaigns. © 2016 The Author(s).

  5. Modified tension band wiring of medial malleolar ankle fractures.

    Science.gov (United States)

    Georgiadis, G M; White, D B

    1995-02-01

    Twenty-two displaced medial malleolar ankle fractures that were treated surgically using the modified tension band method of Cleak and Dawson were retrospectively reviewed at an average follow-up of 25 months. The technique involves the use of a screw to anchor a figure-of-eight wire. There were no malreductions and all fractures healed. Problems with the technique included technical errors with hardware placement, medial ankle pain, and asymptomatic wire migration. Despite this, modified tension band wiring remains an acceptable method for fixation of selected displaced medial malleolar fractures. It is especially suited for small fracture fragments and osteoporotic bone.

  6. Factores de riesgo de bajo peso al nacer Risk factors for low birthweight

    Directory of Open Access Journals (Sweden)

    Marcelo Bortman

    1998-05-01

    Full Text Available El bajo peso al nacer (BPN es el principal factor determinante conocido de la mortalidad infantil. Pese a la notable reducción de las tasas de mortalidad infantil y al aumento de las tasas de supervivencia de niños con BPN, en Neuquén, Argentina, no se han observado descensos notables de las tasas de BPN. El propósito de este estudio fue conocer los factores de riesgo de BPN, su frecuencia en la población y el papel de la atención prenatal en su prevención, y desarrollar una escala de riesgo que permita identificar a las mujeres en mayor riesgo de dar a luz un niño de bajo peso. Con tal propósito se realizó un estudio transversal en el cual se utilizó 50% de los datos del Sistema Informático Perinatal correspondientes al período 1988­1995 y procedentes de los 29 hospitales de la provincia de Neuquén (46 171 nacimientos. Se analizaron la distribución del peso y la frecuencia de los posibles factores de riesgo de BPN. La asociación entre estos factores y el BPN se analizó mediante un modelo de regresión logística. Con los resultados obtenidos se desarrolló una escala aditiva, que fue validada con el 50% restante de los registros de nacimientos. La razón de posibilidades (RP más elevada correspondió a la falta de atención prenatal (RP = 8,78; IC95%: 6,7 a 11,4. Las RP asociadas con una atención prenatal inadecuada, una primera consulta prenatal tardía, preeclampsia o eclampsia, hemorragia o anomalías de la placenta o sus membranas e historia de un hijo previo con BPN fueron mayores de 2,0. El riesgo de tener hijos con BPN también fue más alto en las mujeres mayores de 40 años, las menores de 20, las solteras, las fumadoras, aquellas cuyo intervalo intergenésico fue menor de 18 meses y las que tenían un índice de masa corporal menor de 20. Por último, se encontró una relación lineal directa entre el puntaje en la escala y el riesgo de tener un hijo con BPN.Low birthweight (LBW is the main known determinant of

  7. Requerimiento hídrico de la berenjena Solanum melongena L. bajo

    Directory of Open Access Journals (Sweden)

    Sánchez V. Carlos

    2004-12-01

    Full Text Available

    El objetivo del presente trabajo fue determinar los requerimientos hídricos de dos genotipos de berenjena Solanum melongena L. bajo riego por goteo en el valle del Sinú medio, en época seca. El estudio se hizo en el Centro de Investigación Turipaná, de Corpoica, ubicado en Cereté, Córdoba, en un suelo clasificado como eutropet. Se utilizó un diseño de bloques al azar con un arreglo factorial de parcelas divididas, con dos genotipos de berenjena (Morada y Lila gris bajo cinco dosis de riego 1, 2, 4, 6 y 8 l∙planta -1∙día-1. Los resultados  demostraron que los genotipos de berenjena morada y lila gris se comportaron similarmente, sin presentar diferencias significativas. Hubo diferencias altamente significativas en las variables altura de planta, diámetro del tallo y rendimiento. El tratamiento de riego de 8 l∙planta

  8. Enfermedad periodontal: ¿es factor de riesgo para parto pretérmino, bajo peso al nacer o preeclampsia?

    Directory of Open Access Journals (Sweden)

    José Luis Castaldi

    2006-04-01

    Full Text Available OBJETIVOS: Evaluar si la enfermedad periodontal (EP constituye un factor de riesgo de parto pretérmino, bajo peso al nacer o preeclampsia y si hay alguna relación entre las formas clínicas de la EP y los resultados obstétricos mencionados. MÉTODOS: Estudio analítico, transversal y prospectivo de todas las mujeres que tuvieron su parto en el Hospital Dr. José Penna, de la ciudad de Bahía Blanca, Argentina, entre el 1.º de febrero y el 18 de julio de 2003 y entre el 1.º de marzo y el 31 de mayo de 2004. A las mujeres que cumplieron los criterios de inclusión (ser mayor de 18 años, tener al menos 18 dientes, no ser diabética y que los hijos hubieran sobrevivido al parto se les practicó un examen odontológico en busca de hemorragia al sondaje, movilidad dentaria o inflamación gingival y se realizaron mediciones clínicas de la pérdida de inserción. Se calcularon las razones de posibilidades (odds ratios, RP con sus intervalos de confianza del 95% (IC95% y se ajustaron los resultados por las variables "ser fumadora" y "tener anemia". RESULTADOS: Se registraron 2 003 nacimientos, correspondientes a 1 982 partos. Se excluyeron 420 (21,2% mujeres por no cumplir los criterios de inclusión o por no poder realizárseles el diagnóstico odontológico previsto. De las 1 562 mujeres evaluadas, 809 (51,8% presentaban alguna de las afecciones buscadas; de ellas, 274 (17,5% padecían EP grave y 535 (34,3% tenían gingivitis. En total, 149 (9,5% partos fueron pretérmino, en 161 (10,3% nacieron niños con bajo peso y en 157 (10,0% se presentaron casos de preeclampsia. No se observó asociación alguna entre la EP y el parto pretérmino (RP = 1,06; IC95%: 0,74 a 1,50, el bajo peso al nacer (RP = 1,05; IC95%: 0,74 a 1,47 y la preeclampsia (RP = 0,99; IC95%: 0,70 a 1,40. El riesgo de dar a luz un niño con bajo peso al nacer en el subgrupo de fumadoras de más de 10 cigarrillos diarios fue mayor en las que tenían enfermedad periodontal grave que

  9. PAUTAS PARA LA GESTIÓN INTEGRADA DE LOS RECURSOS HÍDRICOS EN LOS BAJOS SUBMERIDIONALES (ARGENTINA)

    OpenAIRE

    M. PARIS; R. P. MARANO

    2017-01-01

    La cuenca hidrográfi ca es una unidad territorial compleja tanto por sus características naturales, como por las particularidades de la sociedad. Dado que ésta es una “unidad territorial”, entonces los problemas que surjan de la gestión de los recursos hídricos serán de toda la cuenca. En el ámbito de Santa Fe está contemplado un Plan de Manejo Integral de los Bajos Submeridionales. Algunas acciones fueron llevadas a cabo en este marco, pero no hay una Agenda del Agua que sea reconocida po...

  10. Aplicación de tecnologías inalámbricas de bajo consumo para entornos exteriores ferroviarios

    OpenAIRE

    Garrido Calvo, Víctor

    2013-01-01

    El objetivo del proyecto es el análisis del funcionamiento de tecnologías inalámbricas de bajo consumo, tales como ZigBee, aplicadas en el transporte ferroviario de mercancías para la interconexión entre vagones y/o con la locomotora o vagón principal que permitan: - Localizar, posicionar e dentificar el material móvil (trenes / vagones / contenedores) y las mercancías transportadas. - Intercambiar información de manera ágil y flexible entre el material móvil y los Centros de C...

  11. Infecciones del tracto urinario bajo en adultos y embarazadas: consenso para el manejo empírico

    OpenAIRE

    Martinez, E; Osorio, J; Delgado, J; Esparza, G.E; Motoa, G; Blanco, V.M; Hernandez, C.A; Agudelo, A; Aluma, L.J; Betancurt, C.A; Ospina, W; Camargo, J.C; Canaval, H; Castañeda, C; Correa, A

    2013-01-01

    Introducción: La infección no complicada del tracto urinario bajo y la bacteriuria asintomática son causas frecuentes de consulta médica ambulatoria y en el servicio de urgencias en Colombia y el mundo. La falta de pautas y consenso para el manejo, así como la emergencia de resistencia a las múltiples opciones terapéuticas disponibles en los uropatógenos provenientes de la comunidad, hacen necesario elaborar unas recomendaciones que orienten al clínico sobre el abordaje óptimo de estas entida...

  12. Estudio embriológico de Iguana iguana (Linnaeus, 1758) bajo condiciones de incubación controladas

    OpenAIRE

    Ossa Velásquez Jaime de la; Guzmán Lotero Edith Liliana

    2000-01-01

    Se realiza un estudio de Iguana iguana para establecer los estadios embrionarios que caracterizan la especie, bajo condiciones de incubaci6n artificial controladas de 32.5°C y humedad relativa promedio de 90% ± 2, colectándose y fijándose 5 huevos diarios a partir de la postura y durante 67 días. El peso promedio de los huevos fue de 15.4001 g, largo 3.84 mm, ancho 2.7 mm, notándose que estos son independientes del tiempo transcurrido de incubación. El peso de los embriones no presen...

  13. Un análisis de los determinantes del pago bajo Contratos de Préstamo Grupal

    OpenAIRE

    Santiago Pulido, Juan Manuel

    2013-01-01

    En la presente tesis doctoral se estudia la relación entre cohesión social y pago en contratos de préstamo grupal con las herramientas de la economía de redes sociales. En un primer planteamiento, el mecanismo del préstamo grupal se aproxima a uno de contribución voluntaria encontrando que el pago esperado de participar es función directa de la probabilidad de pago individual. Esta última se estudia en primer instancia bajo independencia en los eventos de pago. El mecanismo se tra...

  14. Humedad crítica y repelencia al agua en andisoles colombianos bajo cobertura de pinus patula schltdl y cham.

    OpenAIRE

    Jaramillo Jaramillo, Daniel Francisco

    2011-01-01

    En un lote con Andisoles bajo cobertura de Pinus patula Schltdl y Cham se ubicaron 4 transectos sobre los cuales se hizo un muestreo horizontal cada 5 cm, en 4 profundidades, con el fin de establecer si había una zona de transición de humedad crítica en el suelo que estuviera controlando la presencia de repelencia al agua en él. Se hicieron determinaciones de WDPT en el campo y luego en muestras secadas a 35°C, en laboratorio. En cada condición se determinó el contenido gravimétrico de hum...

  15. Caracterización de 14 genotipos de tomate (Lycopersicon esculentum Mill. cultivados bajo invernadero en Costa Rica

    Directory of Open Access Journals (Sweden)

    José Eladio Monge-Pérez

    2014-11-01

    Full Text Available Se caracterizaron 14 genotipos de tomate producidos bajo invernadero, tanto a nivel cualitativo como cuantitativo. Los datos muestran una amplia variabilidad entre genotipos y brindan información útil a los productores en el proceso de selección del genotipo a utilizar en su sistema productivo, según el nicho de mercado de interés. Se destacan varios genotipos de tomate tipo “cherry! y “uva” por su alto contenido de sólidos solubles, que pueden ser opciones para los consumidores que demandan un producto de alta calidad.

  16. Determinantes sociales de la mortalidad infantil en municipios de bajo índice de desarrollo humano en México

    OpenAIRE

    Duarte-Gómez, María Beatriz; Núñez-Urquiza, Rosa María; Restrepo-Restrepo, José Alonso; Richardson-López-Collada, Vesta Louise

    2015-01-01

    Introducción: Se realizó un estudio con el objetivo de identificar determinantes sociales de mortalidad infantil en zonas rurales en México, y recomendar estrategias para disminuir esta mortalidad. Métodos: Se tomó una muestra por conveniencia de 16 municipios de bajo índice de desarrollo humano. Se identificaron fallecimientos de menores de un año de edad a través de registros oficiales y de entrevistas con autoridades civiles, personal de salud y líderes comunitarios. También se realizar...

  17. Fortificaciones de la II Edad del Hierro en el Bajo Aragón : un estilo regional

    OpenAIRE

    Melguizo , Salvador; Moret , Pierre

    2006-01-01

    International audience; Se estudian en esta comunicación las fortificaciones del final de la época ibérica en dos áreas del Bajo Aragón: la desembocadura del Regallo, en Caspe, con los yacimientos de La Tallada y Palermo I, y el valle medio del Matarraña, entre Calaceite y Valdeltormo, con los yacimientos de San Antonio, Els Castellans y Torre Cremada. Se observa en ellos un patrón repetitivo, caracterizado por la presencia de tres elementos, concentrados en la zona de acceso más vulnerable: ...

  18. Desarrollo comunitario en el medio rural: un proyecto en la mancomunidad de Villas del Bajo Carrion y Ucieza

    OpenAIRE

    Giraldo Rojo, Cristina

    2017-01-01

    Este proyecto de fin de grado ha sido elaborado con el fin de hallar teorías de desarrollo comunitario, así como también realizar un análisis de estas mismas. De igual forma que se han analizado las iniciativas por parte de los diferentes agentes y administraciones, para después elaborar y planificar unas actividades de desarrollo comunitario en la Mancomunidad de Villas del bajo Carrión y Ucieza, situado en la provincia de Palencia. Grado en Educación Social

  19. Incidencia de la estrategia colombiana de desarrollo bajo en carbono en el mercado de bonos de carbono en Colombia

    OpenAIRE

    Castellanos Garcia, Camilo Andres

    2015-01-01

    La presente investigación tiene como objetivo principal determinar el papel de la estrategia colombiana de desarrollo bajo en carbono en el mercado de bonos de carbono en Colombia. Esto con el fin de demostrar que las acciones nacionalmente apropiadas de mitigación NAMAS son un mecanismo de mitigación y puede no tener una incidencia en la oferta ni tampoco en la demanda del mercado de bonos de carbono en Colombia. Esta investigación se llevará a cabo por medio de un estudio de caso con un enf...

  20. Diseño de un cuadricóptero de bajo coste basado en herramientas de software libre

    OpenAIRE

    Ciudad Gómez, Rubén

    2016-01-01

    El presente proyecto tiene como objetivo la realización de un cuadricóptero de bajo coste desarrollado con herramientas de software libre, con el fin de permitir el acceso y modificación del mismo a cualquiera que posea los conocimientos necesarios. Los cuadricópteros se definen como un vehículo aéreo no tripulado con cuatro rotores en los extremos. Los ejemplos existentes de estos tipos de vehículos son casi siempre de grandes cuadricópteros, los cuales utilizan diferentes tecnologías en ...

  1. Riesgos y consecuencias de las prácticas sexuales en adolescentes bajo los efectos de alcohol y otras drogas

    OpenAIRE

    Guillermo Castaño Pérez; Eduardo Arango Tobón; Santiago Morales Mesa; Alexander Rodríguez Bustamante; Carolina Montoya Montoya

    2013-01-01

    Introducción: la sexualidad, y el consumo de alcohol y drogas en los adolescentes, figuran en la actualidad como uno de los asuntos con mayor prioridad para la salud pública. La preocupación radica en reducir los riesgos de infecciones de transmisión sexual, el virus de la inmunodeficiencia humana y los embarazos tempranos no deseados. Objetivo: analizar las prácticas sexuales bajo el efecto de alcohol y otras drogas, y los riesgos que esto implica, en los adolescentes de la ciudad de Medellí...

  2. Desarrollo de alimentos tipo snack de bajo contenido graso a partir de discos de manzana verde

    OpenAIRE

    Tavera Quiroz, María José

    2015-01-01

    Esta investigación se basó en el desarrollo de productos tipo snack bajos en grasa a partir de manzana verde Granny Smith (Malus domestica). Se desarrollaron snacks a partir de manzanas verdes estudiando diferentes alternativas de cocción (fritado, horneado o su combinación) con el objetivo de obtener productos con menor contenido graso que los tradicionales pero con las propiedades que los consumidores valoran en los mismos, como el color y la textura crocante. Para ello se analizó...

  3. Estudios biológicos sobre procambarus clarkii girard (decapoda cambaridae) en las marismas del bajo Guadalquivir

    OpenAIRE

    Cano Sánchez, Esperanza

    1994-01-01

    Procambarus clarkii Girard, es un cangrejo de agua dulce, vulgarmente conocido como cangrejo americano o rojo, originario de Estados Unidos (zona Sur central) y México (zona Noreste) (HOBBS, 1972 a). Fue introducido en Las Marismas del Bajo Guadalquivir en 1974 y debido a que presenta una alta tasa de reproducción, actividad excavadora y buena adaptación a zonas con drásticas fluctuaciones temporales en el nivel del agua (HUNER & BARR, 1984 a), en poco tiempo se extendió por toda la marisma. ...

  4. Determinantes sociales de la mortalidad infantil en municipios de bajo índice de desarrollo humano en México

    OpenAIRE

    Duarte-Gómez, María Beatriz; Núñez-Urquiza, Rosa María; Restrepo-Restrepo, José Alonso; López-Collada, Vesta Louise Richardson

    2015-01-01

    ResumenINTRODUCCIÓN: Se realizó un estudio con el objetivo de identificar determinantes sociales de mortalidad infantil en zonas rurales en México, y recomendar estrategias para disminuir esta mortalidad.MÉTODOS: Se tomó una muestra por conveniencia de 16 municipios de bajo índice de desarrollo humano. Se identificaron fallecimientos de menores de un año de edad a través de registros oficiales y de entrevistas con autoridades civiles, personal de salud y líderes comunitarios. También se reali...

  5. Selección de portafolios usando simulación y optimización bajo incertidumbre

    Directory of Open Access Journals (Sweden)

    Claudia Lorena Martinez Torres

    2004-01-01

    Full Text Available Los métodos utilizados usualmente en la formación de portafolios, son basados en hipótesis que no son reales en mercados emergentes, y en consecuencia no son aplicables a estos mercados. Ellos no indican la forma en que debe ser conformado el portafolio. Se presenta entonces, una metodología basada en simulación y optimización bajo incertidumbre que permite realizar la conformación del portafolio. Se realizan pruebas en el mercado colombiano y la Bolsa de Nueva York.

  6. C2-rational cubic spline involving tension parameters

    Indian Academy of Sciences (India)

    preferred which preserves some of the characteristics of the function to be interpolated. In order to tackle such ... Shape preserving properties of the rational (cubic/quadratic) spline interpolant have been studied ... tension parameters which is used to interpolate the given monotonic data is described in. [6]. Shape preserving ...

  7. Nonlinear transverse vibrations of elastic beams under tension

    International Nuclear Information System (INIS)

    Ichikawa, Y.H.; Konno, Kimiaki; Wadati, Miki.

    1980-02-01

    Nonlinear transverse vibrations of elastic beams under end-thrust have been examined with full account of the rigorous nonlinear relation of curvature and deformation of elastic beams. When the beams are subject to tension, the derived equation is shown to be reduced to one of the new integrable evolution equations discovered by us. (author)

  8. Liquid-liquid interfacial tension of electrolyte solutions

    NARCIS (Netherlands)

    Bier, Markus; Zwanikken, J.W.; van Roij, R.H.H.G.

    2008-01-01

    It is theoretically shown that the excess liquid-liquid interfacial tension between two electrolyte solutions as a function of the ionic strength I behaves asymptotically as (-) for small I and as (±I) for large I. The former regime is dominated by the electrostatic potential due to an unequal

  9. Role perception, job-related tension and organisational confidence ...

    African Journals Online (AJOL)

    Role perception, job-related tension and organisational confidence of the village extension workers in Nsukka zone of Enugu State Agricultural Development ... Data for the study were collected through structured questionnaire administered on 44 VEWS selected, using ... their role-expectations as being important. Many of ...

  10. Aerodynamic Profiles of Women with Muscle Tension Dysphonia/Aphonia

    Science.gov (United States)

    Gillespie, Amanda I.; Gartner-Schmidt, Jackie; Rubinstein, Elaine N.; Abbott, Katherine Verdolini

    2013-01-01

    Purpose: In this study, the authors aimed to (a) determine whether phonatory airflows and estimated subglottal pressures (est-P[subscript sub]) for women with primary muscle tension dysphonia/aphonia (MTD/A) differ from those for healthy speakers; (b) identify different aerodynamic profile patterns within the MTD/A subject group; and (c) determine…

  11. New tensioning equipment saves time at Browns Ferry

    International Nuclear Information System (INIS)

    Wagner, P.

    1996-01-01

    Improved reactor vessel tensioning technology has proved very successful at TVA's Browns Ferry station. The new equipment was used during unit 2's autumn 1994 outage and will be used there at the next outage, scheduled for March 1996. It will be deployed at unit 3, currently in restart mode. (author)

  12. Replicating an Intervention: The Tension between Fidelity and Adaptation

    Science.gov (United States)

    Morrison, Diane M.; Hoppe, Marilyn J.; Gillmore, Mary Rogers; Kluver, Carisa; Higa, Darrel; Wells, Elizabeth A.

    2009-01-01

    Increased awareness of the importance of tailoring interventions to participants' cultures has focused attention on the limited generalizability of a single test of an intervention to determine efficacy. Adaptation is often necessary to replicate interventions across cultures. This produces a tension between fidelity to the original intervention…

  13. Effects of post mortem temperature on rigor tension, shortening and ...

    African Journals Online (AJOL)

    Fully developed rigor mortis in muscle is characterised by maximum loss of extensibility. The course of post mortem changes in ostrich muscle was studied by following isometric tension, shortening and change in pH during the first 24 h post mortem within muscle strips from the muscularis gastrocnemius, pars interna at ...

  14. "Tissue oxygen tension, a determinant of resistance to infection and ...

    African Journals Online (AJOL)

    "Tissue oxygen tension, a determinant of resistance to infection and healing" - An Inaugural Lecture. K Jönsson. Abstract. An Inaugural Lecture Given in the University of Zimbabwe on 21 June 2001. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  15. Modeling combined tension-shear failure of ductile materials

    International Nuclear Information System (INIS)

    Partom, Y

    2014-01-01

    Failure of ductile materials is usually expressed in terms of effective plastic strain. Ductile materials can fail by two different failure modes, shear failure and tensile failure. Under dynamic loading shear failure has to do with shear localization and formation of adiabatic shear bands. In these bands plastic strain rate is very high, dissipative heating is extensive, and shear strength is lost. Shear localization starts at a certain value of effective plastic strain, when thermal softening overcomes strain hardening. Shear failure is therefore represented in terms of effective plastic strain. On the other hand, tensile failure comes about by void growth under tension. For voids in a tension field there is a threshold state of the remote field for which voids grow spontaneously (cavitation), and the material there fails. Cavitation depends on the remote field stress components and on the flow stress. In this way failure in tension is related to shear strength and to failure in shear. Here we first evaluate the cavitation threshold for different remote field situations, using 2D numerical simulations with a hydro code. We then use the results to compute examples of rate dependent tension-shear failure of a ductile material.

  16. First-principles prediction of liquid/liquid interfacial tension

    DEFF Research Database (Denmark)

    Andersson, Martin Peter; Bennetzen, M.V.; Klamt, A.

    2014-01-01

    of groundwater aquifers contaminated by chlorinated solvents to drug delivery and a host of industrial processes. Here, we present a model for predicting interfacial tension from first principles using density functional theory calculations. Our model requires no experimental input and is applicable to liquid...

  17. Closed-Loop Tension Control System for Injection Moulding Machine

    African Journals Online (AJOL)

    When the mould unit is full, this drive keeps transporting filament materials without proper control. This project developed a closed loop feedback tension control system and it is to replace servo motor drive system for the transportation of filament and it demonstrated a new technological advancement and the theory of ...

  18. Creative tensions in youth ministry in a congregational context

    African Journals Online (AJOL)

    2015-02-06

    Feb 6, 2015 ... is here understood as a source of creative energy that informs and guides ... smart phone or .... keep the tension intact and create energy for creative ..... Root, A., 2007, Revisifing relafional youth ministry: From a strategy of ...

  19. Tensions and Dilemmas about Education in Human Rights in Democracy.

    Science.gov (United States)

    Magendzo, Abraham

    1994-01-01

    Asserts that incorporating human rights issues into the curriculum causes tensions, especially in nations with histories of military dictatorships. Describes human rights education in Chile and other Latin American nations. Discusses whether human rights should be a separate curriculum subject or integrated into all courses. (CFR)

  20. Indentation of a floating elastic sheet: geometry versus applied tension.

    Science.gov (United States)

    Box, Finn; Vella, Dominic; Style, Robert W; Neufeld, Jerome A

    2017-10-01

    The localized loading of an elastic sheet floating on a liquid bath occurs at scales from a frog sitting on a lily pad to a volcano supported by the Earth's tectonic plates. The load is supported by a combination of the stresses within the sheet (which may include applied tensions from, for example, surface tension) and the hydrostatic pressure in the liquid. At the same time, the sheet deforms, and may wrinkle, because of the load. We study this problem in terms of the (relatively weak) applied tension and the indentation depth. For small indentation depths, we find that the force-indentation curve is linear with a stiffness that we characterize in terms of the applied tension and bending stiffness of the sheet. At larger indentations, the force-indentation curve becomes nonlinear and the sheet is subject to a wrinkling instability. We study this wrinkling instability close to the buckling threshold and calculate both the number of wrinkles at onset and the indentation depth at onset, comparing our theoretical results with experiments. Finally, we contrast our results with those previously reported for very thin, highly bendable membranes.

  1. Tension and Compression Creep Apparatus for wood-Plastic Composites

    Science.gov (United States)

    Scott E. Hamel; John C. Hermanson; Steven M. Cramer

    2011-01-01

    Design of structural members made of wood-plastic composites (WPC) is not possible without accurate test data for tension and compression. The viscoelastic behavior of these materials means that these data are required for both the quasi-static stress-strain response, and the long-term creep response. Their relative incompressibility causes inherent difficulties in...

  2. The upsurge of tension between Renamo and Frelimo in Mozambique

    African Journals Online (AJOL)

    The upsurge of tension between Renamo and Frelimo in Mozambique: The contest for traditional leadership support. Happy Kayuni. Abstract. Soon after independence in 1975, Mozambique was plunged into a protracted civil war involving the ruling party Frelimo and the rebel movement Renamo. Renamo controlled ...

  3. Investigating the tension load of rubber composites by impact

    Indian Academy of Sciences (India)

    This work deals with establishing the tension load by impact dynamic testing of rubber ... Faculty of Mining, Ecology, Process Control and Geotechnology, Technical University of Košice, Institute of Logistics, Park Komenského 14, 043 84 ...

  4. Measurement of interfacial tension of immiscible liquid pairs in microgravity

    Science.gov (United States)

    Weinberg, Michael C.; Neilson, George F.; Baertlein, Carl; Subramanian, R. Shankar; Trinh, Eugene H.

    1994-01-01

    A discussion is given of a containerless microgravity experiment aimed at measuring the interfacial tension of immiscible liquid pairs using a compound drop rotation method. The reasons for the failure to execute such experiments in microgravity are described. Also, the results of post-flight analyses used to confirm our arguments are presented.

  5. Surface tension of compositions of polyhexametyleneguanidine hydrochloride - surfactants

    Directory of Open Access Journals (Sweden)

    S. Kumargaliyeva

    2012-12-01

    Full Text Available We made up songs bactericidal polyhexamethyleneguanidine hydrochloride (metacyde with the surface-active substances - anionic sodium dodecylsulfate, cationic cetylpyridinium bromide, and nonionic Tween-80 and measured the surface tension of water solutions. The study showed that the composition metacyde with surface-active agents have a greater surface activity than the individual components.

  6. Dousing the tension in the Niger delta through administrative agency

    African Journals Online (AJOL)

    Dousing the tension in the Niger delta through administrative agency: A programme evaluation of Niger delta development commission as an intervention regime. ... the study concludes that because of systemic constraints arising from the hegemonic interests of the dominant coalitions in the Nigerian Social formation, ...

  7. Spectral fatigue analysis of a tensioned riser compliant tower

    NARCIS (Netherlands)

    Karadeniz, H.; Vrouwenvelder, A.C.W.M.; Shi, C.

    1998-01-01

    In this paper, the conceptual Tensioned Riser Compliant Tower (TRCT) structure of the Shell Oil, which is developed for a region of approximately 600 meter water depth of the West of Shetlands in the North Sea, is analyzed by using the SAPOS program of the Delft University of Technology. The fatigue

  8. Nanofluidic bubble pump using surface tension directed gas injection

    NARCIS (Netherlands)

    Tas, Niels Roelof; Berenschot, Johan W.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt; van den Berg, Albert

    2002-01-01

    A new concept for liquid manipulation has been developed and implemented in surface-micromachined fluid channels. It is based on the surface tension directed injection of a gas into the liquid flow through micrometer-sized holes in the microchannel wall. The injected gas is directed to an exhaust by

  9. Electrical injuries due to railway high tension cables.

    Science.gov (United States)

    Reichl, M; Kay, S

    1985-08-01

    We have noted a large number of young boys being admitted to our Unit with burns due to railway high tension cables. On review of these cases we have noted: most of the burns were due to arcing, there is a high level of ignorance among the population at risk. We propose some ways of preventing these injuries.

  10. Minimally invasive tension band wiring technique for olecranon fractures.

    Science.gov (United States)

    Takada, Naoya; Kato, Kenji; Fukuta, Makoto; Wada, Ikuo; Otsuka, Takanobu

    2013-12-01

    Some types of implants, such as plates, screws, wires, and nails, have been used for open reduction and internal fixation of olecranon fractures. A ≥ 10 cm longitudinal incision is used for open reduction and internal fixation of olecranon fractures. According to previous studies, tension band wiring is a popular method that gives good results. However, back out of the wires after the surgery is one of the main postoperative complications. Moreover, if the Kirschner wires are inserted through the anterior ulnar cortex, they may impinge on the radial neck, supinator muscle, or biceps tendon. Herein, we describe the minimally invasive tension band wiring technique using Ring-Pin. This technique can be performed through a 2 cm incision. Small skin incisions are advantageous from an esthetic viewpoint. Ring-Pin was fixed by using a dedicated cable wire that does not back out unless the cable wire breaks or slips out of the dedicated metallic clamp. As the pins are placed in intramedullary canal, this technique does not lead to postoperative complications that may occur after transcortical fixation by conventional tension band wiring. Minimally invasive tension band wiring is one of the useful options for the treatment of olecranon fractures with some advantages.

  11. Splines under tension for gridding three-dimensional data

    International Nuclear Information System (INIS)

    Brand, H.R.; Frazer, J.W.

    1982-01-01

    By use of the splines-under-tension concept, a simple algorithm has been developed for the three-dimensional representation of nonuniformly spaced data. The representations provide useful information to the experimentalist when he is attempting to understand the results obtained in a self-adaptive experiment. The shortcomings of the algorithm are discussed as well as the advantages

  12. Population and economy in the Bajo Ebro in Roman times. Basic concepts for a rural landscape model | Poblamiento y economía en el Bajo Ebro en época romana. Bases para un modelo de paisaje rural

    Directory of Open Access Journals (Sweden)

    Víctor Revilla Calvo

    1994-12-01

    Full Text Available This paper analyses the settlement patterns and the social-economic structures in Bajo Ebro in Roman times. It covers especifically relationships among settlements, rural landscape, structures of agricultural production and landowning. Likewise, the origin and historical evolution of these structures are studied, as well as their role within a broader political, social and economic framework in the Province of Tarraconensis. | El artículo analiza las formas del poblamiento y las estructuras socio-económicas del Bajo Ebro en época romana. Se plantean, en particular, las relaciones entre la distribución del habitat, el paisaje rural, las estructuras de la producción agrícola y de la propiedad. Se analiza igualmente el origen y evolución histórica de estas estructuras, así como su integración en un marco político, social y económico más amplio, constituido por la provincia Tarraconense.

  13. Hydraulic nuts (HydraNuts) for reactor vessel tensioning

    International Nuclear Information System (INIS)

    Greenwell, Steve

    2008-01-01

    The paper will present how the introduction of hydraulic nuts - HydraNuts, has reduced critical path times, dose exposure for workers and improved working safety conditions around the reactor vessel during tensioning or de-tensioning operations. It will focus upon detailing the advantages realized by utilities that have introduced the technology and providing examples of the improvements made to the process as well as discussing the engineering design change packages required to make the conversion to the new system. HydraNuts replace the traditional mechanical nut/stud tensioning equipment, combining the two functions into a single system, designed for easy installation and operation by one individual. The primary components of the HydraNut can be assembled without the need for external crane or hoist support and are designed so that each sub assembly can be fitted separately. Once all HydraNuts are fitted to the Rx vessel studs and are sitting on the main Rx vessel head flange, then a system of flexible hydraulic hoses is connected to them, forming a closed loop hydraulic harness, which will allow for simultaneous pressurization of all HydraNuts. Hydraulic pressure is obtained by the use of a hydraulic pumping unit and the resultant load generated in each HydraNut is transferred to the stud and main flange closure is obtained. While maintaining hydraulic pressure, a locking ring is rotated into place on the HydraNut assembly that will support the tensioned load mechanically when the hydraulic pressure is released from the hose harness assembly. The hose harness is removed and the HydraNut is now functioning as a mechanical nut retaining the tensioned load. The HydraNut system for Rx vessel applications was first introduced into a plant in the U.S. in October 2006 and based upon the benefits realized subsequent projects are under way within the Asian and U.S. operating fleet. (author)

  14. Constraining brane tension using rotation curves of galaxies

    Science.gov (United States)

    García-Aspeitia, Miguel A.; Rodríguez-Meza, Mario A.

    2018-04-01

    We present in this work a study of brane theory phenomenology focusing on the brane tension parameter, which is the main observable of the theory. We show the modifications steaming from the presence of branes in the rotation curves of spiral galaxies for three well known dark matter density profiles: Pseudo isothermal, Navarro-Frenk-White and Burkert dark matter density profiles. We estimate the brane tension parameter using a sample of high resolution observed rotation curves of low surface brightness spiral galaxies and a synthetic rotation curve for the three density profiles. Also, the fittings using the brane theory model of the rotation curves are compared with standard Newtonian models. We found that Navarro-Frenk-White model prefers lower values of the brane tension parameter, on the average λ ∼ 0.73 × 10‑3eV4, therefore showing clear brane effects. Burkert case does prefer higher values of the tension parameter, on the average λ ∼ 0.93 eV4 ‑ 46 eV4, i.e., negligible brane effects. Whereas pseudo isothermal is an intermediate case. Due to the low densities found in the galactic medium it is almost impossible to find evidence of the presence of extra dimensions. In this context, we found that our results show weaker bounds to the brane tension values in comparison with other bounds found previously, as the lower value found for dwarf stars composed of a polytropic equation of state, λ ≈ 104 MeV4.

  15. Apparatus producing constant cable tension for intermittent demand

    Science.gov (United States)

    Lauritzen, Ted

    1985-01-01

    The disclosed apparatus produces constant tension in superconducting electrical cable, or some other strand, under conditions of intermittent demand, as the cable is unreeled from a reel or reeled thereon. The apparatus comprises a pivotally supported swing frame on which the reel is rotatably supported, a rotary motor, a drive train connected between the motor and the reel and including an electrically controllable variable torque slip clutch, a servo transducer connected to the swing frame for producing servo input signals corresponding to the position thereof, a servo control system connected between the transducer and the clutch for regulating the torque transmitted by the clutch to maintain the swing frame in a predetermined position, at least one air cylinder connected to the swing frame for counteracting the tension in the cable, and pressure regulating means for supplying a constant air pressure to the cylinder to establish the constant tension in the cable, the servo system and the clutch being effective to produce torque on the reel in an amount sufficient to provide tension in the cable corresponding to the constant force exerted by the air cylinder. The drive train also preferably includes a fail-safe brake operable to its released position by electrical power in common with the servo system, for preventing rotation of the reel if there is a power failure. A shock absorber and biasing springs may also be connected to the swing frame, such springs biasing the frame toward its predetermined position. The tension in the cable may be measured by force measuring devices engageable with the bearings for the reel shaft, such bearings being supported for slight lateral movement. The reel shaft is driven by a Shmidt coupler which accommodates such movement.

  16. Apparatus producing constant cable tension for intermittent demand

    International Nuclear Information System (INIS)

    Lauritzen, T.

    1985-01-01

    The disclosed apparatus produces constant tension in superconducting electrical cable, or some other strand, under conditions of intermittent demand, as the cable is unreeled from a reel or reeled thereon. The apparatus comprises a pivotally supported swing frame on which the reel is rotatably supported, a rotary motor, a drive train connected between the motor and the reel and including an electrically controllable variable torque slip clutch, a servo transducer connected to the swing frame for producing servo input signals corresponding to the position thereof, a servo control system connected between the transducer and the clutch for regulating the torque transmitted by the clutch to maintain the swing frame in a predetermined position, at least one air cylinder connected to the swing frame for counteracting the tension in the cable, and pressure regulating means for supplying a constant air pressure to the cylinder to establish the constant tension in the cable, the servo system and the clutch being effective to produce torque on the reel in an amount sufficient to provide tension in the cable corresponding to the constant force exerted by the air cylinder. The drive train also preferably includes a fail-safe brake operable to its released position by electrical power in common with the servo system, for preventing rotation of the reel if there is a power failure. A shock absorber and biasing springs may also be connected to the swing frame, such springs biasing the frame toward its predetermined position. The tension in the cable may be measured by force measuring devices engageable with the bearings for the reel shaft, such bearings being supported for slight lateral movement. The reel shaft is driven by a Shmidt coupler which accommodates such movement

  17. LOCAL GENIUS AS SOCIO-CULTURAL CAPITAL FOR EMPOWERING THE BAJO ETHNIC PEOPLE RESIDING AT THE COASTAL AREA OF BUNGIN PERMAI VILLAGE, SOUTH EAST SULAWESI

    Directory of Open Access Journals (Sweden)

    La Ode Ali Basri

    2012-11-01

    Full Text Available In this dissertation the local genius as socio-cultural capital for empowering theBajo ethnic people residing at the costal area of Bungin Permai Village, TinanggeaDistrict, South Konawe Regency, South Sulawesi Province is discussed. The Bajo ethnicpeople have a set of local genius within their socio-cultural system which is reflected intheir belief, tradition and custom and is used as the reference for conceiving andexplaining the objective and essence of life and the world. However, such local geniushas not functioned optimally yet as they are still marginalized.This research is focused on (1 what forms of local genius serve as the sociocultural capital for empowering the Bajo ethnic group residing at the coastal area?; (2how the local genius is developed to empower the Bajo ethnic people residing at thecoastal area?; and (3 what factors which may support and obstruct the local genius usedas the socio cultural capital for empowering the Bajo ethnic people residing at the coastalarea? Qualitative method is employed in this study with the approach of cultural studies.The theories used are the post colonial theory, structural theory, generative theory,hegemony theory and semiotic theory. The techniques used for collecting the data neededare participative observation, in-depth interview, library research, and focus groupdiscussion. The data obtained are analytically and descriptively processed and arepresented in the forms of narration, tables and visual illustration.The results of the study show that the Bajo ethnic people residing at BunginPermai Village have a set of local genius which may be potentially used as the sociocultural capital for empowering their community such as (1 indigenous skills andknowledge; (2 working culture; and (3 local organizations. The development of theindigenous skills and knowledge (pengetahuan dan ketrampilan asli; hereon abbreviatedto PKA and the revitalization of their local organizations may be used as the

  18. Influence on cervical MR imaging by tension. Comparison between the picture quality of cervical MR image and tension

    International Nuclear Information System (INIS)

    Iseki, Tadahiro; Okano, Tamotsu; Kanou, Norio; Tanaka, Kazuharu; Kawasaki, Kouichi; Kawachi, Toshiaki

    2003-01-01

    In our first report, we compared influence on cervical MR image (C-MRI) by fear and anxiety on between the first time and experienced patients, in which the significant difference was not seen between those patients. Then, the present study, we made a comparison of the picture sharpness of C-MRI on between patients who were in states of tension and not, and on among tense patients by several causes. Our study showed the tendency which the good quality pictures were easy to be obtained in the experienced patients who were tensely and the poor quality pictures were in the patients who were not, which could not demonstrated the statistical significant difference. However, as compared the respective cause which induces tension with the picture sharpness, the patients with tenses caused by MR device showed to be difficult to be obtained the good quality pictures. The present study suggested that ''unsuitable tension'', which was overstrung due to fear and anxiety from MR device, was difficult to obtain good quality picture of C-MRI, and that ''suitable tension'', with which could be kept still during the examination, was easy to do it. (author)

  19. Análisis multifactorial de los factores de riesgo de bajo peso al nacer en Salvador, Bahia

    Directory of Open Access Journals (Sweden)

    Solla Jorge José Santos Pereira

    1997-01-01

    Full Text Available El presente estudio constituye un análisis multifactorial de los factores de riesgo de bajo peso al nacer en un grupo de recién nacidos en una zona urbana del Brasil. Se incluyeron en el estudio un total de 1 023 nacidos vivos, dados a luz en cuatro maternidades de Salvador, Bahia, entre julio de 1987 y febrero de 1988. Las fuentes de información fueron las historias clínicas y las entrevistas con las madres en la maternidad. El análisis se realizó mediante regresión logística. En el modelo final los factores de riesgo incluidos fueron los siguientes: edad materna menos de 21 años o más de 35; edad gestacional menos de 38 semanas; resultado desfavorable del embarazo anterior; intervalo intergenésico previo de 12 meses o menos; tabaquismo; e hipertensión. Se presentan los valores del riesgo atribuible poblacional para los factores de riesgo incluidos en el modelo final. Esos factores deben emplearse para detectar a las gestantes con alto riesgo de dar a luz un niño de bajo peso, a las que debe brindarse mayor atención prenatal.

  20. Bajo peso al nacer y embarazo en la adolescencia en cinco consultorios del médico de la familia

    Directory of Open Access Journals (Sweden)

    Ramón Pérez Queda

    1995-06-01

    Full Text Available Se realizó un estudio de 120 embarazadas en un área de 5 consultorios del médico de la familia en un período que comprendió de enero de 1987 a enero de 1990; de ellas, 56 eran menores de 20 años para el 46,6 %. Se realizó un estudio comparativo entre éstas y las gestantes de más de 20 años de edad, y se observó que las adolescentes presentaron mayor número de recién nacidos con bajo peso (88 % y partos pretérminos. El consumo del tabaco y la desnutrición materna fueron factores importantes que se añadieron a la adolescencia en el resultado del bajo peso al nacer.A study was performed on 120 pregnant women in an area of 5 medical offices of the Family Doctor plan from January 1987 to January 1990. Of them 56 were under 20 years of age accounting for 46,6 %. A comparative study was carried out between this group and pregnant women over 20 years, and it was observed that teenagers had a greater number of low birth weight infants (88 % and preterm deliveries. Smoking and maternal malnutrition were considered as very important factors in addition to adolescence for low birth weight.

  1. Estudio del comportamiento de la escayola reforzada con fibras de sisal, para componentes en viviendas de bajo coste

    Directory of Open Access Journals (Sweden)

    de Oteiza San José, Ignacio

    1993-08-01

    Full Text Available The present article is a brief description of the work done for the elaboration of the doctoral thesis and its conclusions. Starting from the possibilities of using plaster in developing countries, due to its abundance and low cost, a series of mechanical tests have been carried out in order to learn about the physical and mechanical properties of plaster reinforced with sisal fibres for its future use in components for low cost housing.

    El presente artículo es una breve descripción de los trabajos realizados para la elaboración de la tesis doctoral y de las conclusiones de la misma. Partiendo de las posibilidades de utilización en los países en vías de desarrollo del material de escayola, por su abundancia y bajo coste, se llevan a cabo una serie de ensayos mecánicos, con el fin de conocer las propiedades físicas y mecánicas de la escayola reforzada con fibras de sisal, para una futura aplicación en componentes para viviendas de bajo coste.

  2. Anterior cruciate ligament graft tensioning. Is the maximal sustained one-handed pull technique reproducible?

    Directory of Open Access Journals (Sweden)

    Hirpara Kieran M

    2011-07-01

    Full Text Available Abstract Background Tensioning of anterior cruciate ligament (ACL reconstruction grafts affects the clinical outcome of the procedure. As yet, no consensus has been reached regarding the optimum initial tension in an ACL graft. Most surgeons rely on the maximal sustained one-handed pull technique for graft tension. We aim to determine if this technique is reproducible from patient to patient. Findings We created a device to simulate ACL reconstruction surgery using Ilizarov components and porcine flexor tendons. Six experienced ACL reconstruction surgeons volunteered to tension porcine grafts using the device to see if they could produce a consistent tension. None of the surgeons involved were able to accurately reproduce graft tension over a series of repeat trials. Conclusions We conclude that the maximal sustained one-handed pull technique of ACL graft tensioning is not reproducible from trial to trial. We also conclude that the initial tension placed on an ACL graft varies from surgeon to surgeon.

  3. Tensions in the Parent and Adult Child Relationship: Links to Solidarity and Ambivalence

    Science.gov (United States)

    Birditt, Kira S.; Miller, Laura M.; Fingerman, Karen L.; Lefkowitz, Eva S.

    2009-01-01

    Tensions are normative in the parent and adult child relationship, but there is little research on the topics that cause the most tension or whether tensions are associated with overall relationship quality. Adult sons and daughters, aged 22 to 49, and their mothers and fathers (N = 158 families, 474 individuals) reported the intensity of different tension topics and relationship quality (solidarity and ambivalence) with one another. Tensions varied between and within families by generation, gender and age of offspring. In comparison to tensions regarding individual issues, tensions regarding the relationship were associated with lower affective solidarity and greater ambivalence. Findings are consistent with the developmental schism hypothesis, which indicates that parent-child tensions are common and are the result of discrepancies in developmental needs which vary by generation, gender, and age. PMID:19485648

  4. Anterior cruciate ligament graft tensioning. Is the maximal sustained one-handed pull technique reproducible?

    LENUS (Irish Health Repository)

    O'Neill, Barry J

    2011-07-20

    Abstract Background Tensioning of anterior cruciate ligament (ACL) reconstruction grafts affects the clinical outcome of the procedure. As yet, no consensus has been reached regarding the optimum initial tension in an ACL graft. Most surgeons rely on the maximal sustained one-handed pull technique for graft tension. We aim to determine if this technique is reproducible from patient to patient. Findings We created a device to simulate ACL reconstruction surgery using Ilizarov components and porcine flexor tendons. Six experienced ACL reconstruction surgeons volunteered to tension porcine grafts using the device to see if they could produce a consistent tension. None of the surgeons involved were able to accurately reproduce graft tension over a series of repeat trials. Conclusions We conclude that the maximal sustained one-handed pull technique of ACL graft tensioning is not reproducible from trial to trial. We also conclude that the initial tension placed on an ACL graft varies from surgeon to surgeon.

  5. Automatic control of arterial carbon dioxide tension in mechanically ventilated patients.

    Science.gov (United States)

    Fernando, Tyrone; Cade, John; Packer, John

    2002-12-01

    This paper presents a method of controlling the arterial carbon dioxide tension of patients receiving mechanical ventilation. Controlling of the CO2 tension is achieved by regulating the ventilator initiated breath frequency and also volume per breath.

  6. Corrosion characteristics of post-tensioning strands in ungrouted ducts : summary.

    Science.gov (United States)

    2011-01-01

    To prevent corrosion of post-tensioning strands, FDOT construction specifications currently require post-tensioning ducts to be grouted within seven calendar days of strand installation. This period challenges construction schedules on large projects...

  7. Emerging Tensions at the Interface of Artificial Intelligence, IPRs & Competition Law in the Health & Life Sciences

    DEFF Research Database (Denmark)

    Minssen, Timo

    This presentation: • describes the interface between Big Data, IPRs & competition law in the life sciences. • highlights selected life-science areas, where tensions and potential clashes are crystallizing. • discusses how these tensions could be addressed...

  8. Effect of potential attraction term on surface tension of ionic liquids

    Science.gov (United States)

    Vaziri, N.; Khordad, R.; Rezaei, G.

    2018-03-01

    In this work, we have studied the effect of attraction term of molecular potential on surface tension of ionic liquids (ILs). For this purpose, we have introduced two different potential models to obtain analytical expressions for the surface tension of ILs. The introduced potential models have different attraction terms. The obtained surface tensions in this work have been compared with other theoretical methods and also experimental data. Using the calculated surface tension, the sound velocity is also estimated. We have studied the structural effects on the surface tensions of imidazolium-based ionic liquids. It is found that the cation alkyl chain length and the anion size play important roles to the surface tension of the selected ionic liquids. The calculated surface tensions show a good harmony with experimental data. It is clear that the attraction term of molecular potential has an important role on surface tension and sound velocity of our system.

  9. Transitional Failure of Carbon Nanotube Systems under a Combination of Tension and Torsion

    OpenAIRE

    Jeong, Byeong-Woo

    2012-01-01

    Transitional failure envelopes of single- and double-walled carbon nanotubes under combined tension-torsion are predicted using classical molecular dynamics simulations. The observations reveal that while the tensile failure load decreases with combined torsion, the torsional buckling moment increases with combined tension. As a result, the failure envelopes under combined tension-torsion are definitely different from those under pure tension or torsion. In such combined loading, there is a m...

  10. Tension-compression asymmetry modelling: strategies for anisotropy parameters identification.

    Directory of Open Access Journals (Sweden)

    Barros Pedro

    2016-01-01

    Full Text Available This work presents details concerning the strategies and algorithms adopted in the fully implicit FE solver DD3IMP to model the orthotropic behavior of metallic sheets and the procedure for anisotropy parameters identification. The work is focused on the yield criterion developed by Cazacu, Plunkett and Barlat, 2006 [1], which accounts for both tension–compression asymmetry and orthotropic plastic behavior. The anisotropy parameters for a 2090-T3 aluminum alloy are identified accounting, or not, for the tension-compression asymmetry. The numerical simulation of a cup drawing is performed for this material, highlighting the importance of considering tension-compression asymmetry in the prediction of the earing profile, for materials with cubic structure, even if this phenomenon is relatively small.

  11. Checks and balances: the welcomed tension between philosophy and science.

    Science.gov (United States)

    Watson, Jamie Carlin; Arp, Robert

    2008-03-01

    There is a tension between science and philosophy, but this tension need not engender enmity or derision. Scientists and philosophers can work together, and we argue that working together is beneficial to both, even if it is sometimes uncomfortable. We offer examples of how philosophy can autonomously and effectively inform scientific practice. Science and philosophy share certain methodological concerns and practices; therefore, scientists who disregard philosophy are vulnerable to critical conceptual mistakes. If our arguments are correct, and if it can also be shown that science informs philosophy, then, while it is possible for both disciplines to operate autonomously, each should welcome the checks and balances that each provides for one another in the investigation and explanation of reality.

  12. Post Traumatic Tension Pneumocephalus: The Mount Fuji Sign

    LENUS (Irish Health Repository)

    Ryan, J

    2017-04-01

    Pneumocephalus is defined as the presence of intracranial air. This is most commonly secondary to a traumatic head injury. Tension pneumocephalus presents radiologically with compression of the frontal lobes and widening of the interhemispheric space between the frontal lobes. It is often termed the Mount Fuji sign due to a perceived similarity with an iconic mountain peak in Japan. We present the case of a 52-year-old gentleman who presented to the emergency department shortly before 8am on a Saturday morning following an assault. He was alert and ambulatory with no clinical evidence of raised intracranial pressure. A plain radiograph of the facial bones showed significant pneumocephalus. A later CT was consistent with a tension pneumocephalus which usually necessitates urgent decompression.The patient showed no clinical signs or symptoms of raised intracranial pressure and was managed conservatively. He was discharged home 16 days later with no neurological deficit

  13. Lateral Tension-Induced Penetration of Particles into a Liposome

    Directory of Open Access Journals (Sweden)

    Kazuki Shigyou

    2017-07-01

    Full Text Available It is important that we understand the mechanism of the penetration of particles into a living cell to achieve advances in bionanotechnology, such as for treatment, visualization within a cell, and genetic modification. Although there have been many studies on the application of functional particles to cells, the basic mechanism of penetration across a biological membrane is still poorly understood. Here we used a model membrane system to demonstrate that lateral membrane tension drives particle penetration across a lipid bilayer. After the application of osmotic pressure, fully wrapped particles on a liposome surface were found to enter the liposome. We discuss the mechanism of the tension-induced penetration in terms of narrow constriction of the membrane at the neck part. The present findings are expected to provide insight into the application of particles to biological systems.

  14. Tension Pneumocephalus with Diplegia and Deterioration of Consciousness

    Directory of Open Access Journals (Sweden)

    Harald Prüss

    2011-02-01

    Full Text Available Tension pneumocephalus results from intracranial air under pressure as a rare complication after head injury or craniofacial surgery. A 58-year-old man underwent ethmoid sinus surgery and subsequently developed rapidly progressive global headache, restlessness, diplegia with sensory loss, and deterioration of the conscious level. A head CT demonstrated extensive pneumocephalus with gross compression of the brain. The frontal retention of air caused widening of the interhemispheric fissure leading to a peaked appearance of the frontal poles, referred to as the ‘Mount Fuji sign’. Surgical revision of a dural air leak resulted in rapid improvement and full clinical resolution. Early diagnosis of tension pneumocephalus and emergent surgical treatment are crucial to prevent life-threatening deterioration.

  15. Iatrogenic tension pneumothorax in children: two case reports

    Directory of Open Access Journals (Sweden)

    Mayordomo-Colunga Juan

    2009-06-01

    Full Text Available Abstract Introduction Two cases of iatrogenic tension pneumothorax in children are reported. Case presentations Case 1: A 2-year-old boy with suspected brain death after suffering multiple trauma suddenly developed intense cyanosis, extreme bradycardia and generalized subcutaneous emphysema during apnea testing. He received advanced cardiopulmonary resuscitation and urgent bilateral needle thoracostomy. Case 2: A diagnostic-therapeutic flexible bronchoscopy was conducted on a 17-month-old girl, under sedation-analgesia with midazolam and ketamine. She very suddenly developed bradycardia, generalized cyanosis and cervical, thoracic and abdominal subcutaneous emphysema. Urgent needle decompression of both hemithoraces was performed. Conclusion In techniques where gas is introduced into a child's airway, it is vital to ensure its way out to avoid iatrogenic tension pneumothorax. Moreover, the equipment to perform an urgent needle thoracostomy should be readily available.

  16. Massage Therapy and Frequency of Chronic Tension Headaches

    Science.gov (United States)

    Quinn, Christopher; Chandler, Clint; Moraska, Albert

    2002-01-01

    Objectives. The effect of massage therapy on chronic nonmigraine headache was investigated. Methods. Chronic tension headache sufferers received structured massage therapy treatment directed toward neck and shoulder muscles. Headache frequency, duration, and intensity were recorded and compared with baseline measures. Results. Compared with baseline values, headache frequency was significantly reduced within the first week of the massage protocol. The reduction of headache frequency continued for the remainder of the study (P = .009). The duration of headaches tended to decrease during the massage treatment period (P = .058). Headache intensity was unaffected by massage (P = .19). Conclusions. The muscle-specific massage therapy technique used in this study has the potential to be a functional, nonpharmacological intervention for reducing the incidence of chronic tension headache. PMID:12356617

  17. Changes in transcutaneous oxygen tension during exercise in pulmonary emphysema.

    OpenAIRE

    Hughes, J A; Gray, B J; Hutchison, D C

    1984-01-01

    Continuous measurements of transcutaneous oxygen tension (tcPO2) were made in 23 patients with radiological evidence of emphysema, at rest and during a maximal progressive exercise test. tcPO2 during the final phase of exercise was compared with tcPO2 at rest; the mean change (exercising minus resting value) in tcPO2 (delta tcPO2) was -0.8 mm Hg (SD 10.5, range -18 to +25) (-0.1 kPa (SD 1.4, range -2.4 to +3.3]. delta tcPO2 was correlated with: resting arterial oxygen tension (PaO2) (r = 0.60...

  18. Uruguay 1985-2005: Dimensiones y tensiones de la democracia

    Directory of Open Access Journals (Sweden)

    Yamandú Acosta

    2008-07-01

    Full Text Available El texto es una aproximación problematizadora a la democracia uruguaya desde su recuperación en 1985 hasta el inicio del primer gobierno de izquierda en 2005. Se expone sobre el sentido de las condiciones posautoritaria y postransicional de la misma, se la caracteriza como democracia de seguridad mercantil en sinergia con la construcción politicista de la misma que, reducida a régimen de gobierno, parece promover una institucionalidad funcional a lo estructural y disfuncional a las necesidades humanas, que mediadas por las sucesivas y coexistentes generaciones de derechos humanos hace a sus dimensiones y tensiones centrales, desde las cuales el protagonismo democratizador de los actores supone articular dinámicamente las relaciones y tensiones entre las instituciones y el sujeto, en una democracia con las singularidades de la dimensión histórica y utópica de la uruguaya, que finalmente se esboza.

  19. The idea of animal welfare - developments and tensions

    DEFF Research Database (Denmark)

    Sandøe, Peter; Jensen, Karsten Klint

    2013-01-01

    This paper focuses on developments and tensions within the idea of animal welfare. There is divergence among those who believe in the idea of animal welfare. First, we discuss what it takes for farm animal welfare to be good enough. How far should society go beyond the starting point...... of the Brambell Committee, which was to prevent avoidable suffering? Secondly, we turn to the tricky question of how welfare should be distributed between animals. Here, a tension within the concept of animal welfare, between a focus on the indivudual animal and on the herd, flock or shoal, is pointed out....... Finally, the role of economic considerations is considered, given that animal production takes place in a global market with free trade between countries with various standards of animal welfare....

  20. Tension layer winding of cable-in-conduit conductor

    International Nuclear Information System (INIS)

    Devernoe, A.; Ciancetta, G.; King, M.; Parizh, M.; Painter, T.; Miller, J.

    1996-01-01

    A 710 mm i.d. by 440 mm long, 6 layer Cable-in-Conduit (CIC) coil was precision tension layer wound with Incoloy 908 jacketed conductor to model winding technology that will be used for the Nb 3 Sn outsert coils of the 45 Tesla Hybrid Magnet Project at the US National High Magnetic Field Laboratory. This paper reports on the set up of a new winding facility with unique capabilities for insulating and winding long length CIC conductor and on special procedures which were developed to wind and support layer to layer transitions and to safely form conductor into and out of the winding. Analytical methods used to predict conduit keystoning, springback and back tensioning requirements before winding are reported in comparison to results obtained during winding and actual winding build-up dimensions on a layer by layer basis in comparison to design requirements

  1. Superdualities, brane tensions and massive IIA/IIB duality

    International Nuclear Information System (INIS)

    Lavrinenko, I.V.; Lue, H.; Pope, C.N.; Stelle, K.S.

    1999-01-01

    The gauge transformations of p-form fields in supergravity theories acquire a non-commuting character when one introduces potentials both for the theory's original field strengths and for their duals. This has previously been shown in the 'doubled' formalism for maximal supergravities, where a generalised duality relation between original and dual field strengths replaces the equations of motion. In the doubled formalism, the gauge transformations generate a superalgebra, and the corresponding symmetries have accordingly been called 'superdualities'. The corresponding Noether charges form a representation of the cohomology ring on the space-time manifold. In this paper, we show that the gauge symmetry superalgebra implies certain non-trivial relations among the various p-brane tensions, which can straightforwardly be read off from the superalgebra commutation relations. This provides an elegant derivation of the brane-tension relations purely within a given theory, without the need to make use of duality relations between different theories, such as the type IIA/IIB T-duality, although the results are consistent with such dualities. We present the complete set of brane-tension relations in M-theory, in the type IIA and type IIB theories, and in all the lower-dimensional maximal supergravities. We also construct a doubled formalism for massive type IIA supergravity, and this enables us to obtain the brane-tension relations involving the D8-brane, purely within the framework of the massive IIA theory. We also obtain explicit transformations for the nine-dimensional T-duality between the massive type IIA theory and the Scherk-Schwarz reduced type IIB theory

  2. Review of Preliminary Analysis Techniques for Tension Structures.

    Science.gov (United States)

    1984-02-01

    however,a linear dinamic analysis can be conducted for purposes of preliminary design, relative to the static configuration. It is noted that the amount of...16 Chapter 3. PRELIMINARY DESIGN OF TENSION STRUCTURES . . .. .. .. .... 22 S.3.1 Cable Systems . . . . . . . . . . . . .. .. .. .... 23...3.1.1 Singly-Connected Segments. .. .... ... 24 3.1.2 Multiply-Connected Segments . . .. .. .. .. 27 3.1.3 Linearized Dynamics of Cable Systems . . . . 29

  3. Globalization, financial capitalism, and corporate social responsibility: Structural tensions

    OpenAIRE

    David Barbosa Ramírez; Christian Medina López; Myriam Vargas López

    2014-01-01

    Globalization and financial capitalism keep a synergy in a global context whose problems such as environmental degradation, social inequity, economic crises and corruption are intensified. Corporate Social Responsibility emerges as a mechanism that seeks to mitigate some of these problems, although its effectiveness and impact today are challenged. The system which globalization, financial capitalism and social responsibility are a part of, is currently facing a number of structural tensions ...

  4. Fatal Tension Pneumoperitoneum Due to Non-Accidental Trauma

    OpenAIRE

    Thornton, Stephen L.; Hunter, Jeremy; Scott, Mark

    2015-01-01

    A previously healthy two-year-old boy presented to the emergency department with vomiting. He was cyanotic with mottling of both lower extremities. He was in respiratory distress with retractions and diminished breath sounds. His abdomen was distended and rigid. He had a pulse of 170 beats per minute, blood pressure of 144/69mmHg and respiratory rate of 42 breaths per minute. He was endotracheally intubated. Chest and abdominal radiographs demonstrated a tension pneumo...

  5. An adult case of giant bronchogenic cyst mimicking tension pneumothorax.

    Science.gov (United States)

    Yalcinkaya, Serhat; Vural, A Hakan; Ozal, Hasan

    2010-10-01

    Bronchogenic cysts are usually discovered only incidentally in the adult. A giant bronchogenic cyst in a 19-year-old woman presenting with pain and shortness of breath was mistaken for tension pneumothorax and initially treated with tube thoracostomy. Giant bullae were diagnosed by computed tomography. Bullae resection was undertaken, but the remaining lung tissue required pneumonectomy. Pathologic examination of the specimen confirmed bronchogenic cyst.

  6. Fatal Tension Pneumoperitoneum Due to Non-Accidental Trauma

    Directory of Open Access Journals (Sweden)

    Stephen L. Thornton

    2015-10-01

    Full Text Available A previously healthy two-year-old boy presented to the emergency department with vomiting. He was cyanotic with mottling of both lower extremities. He was in respiratory distress with retractions and diminished breath sounds. His abdomen was distended and rigid. He had a pulse of 170 beats per minute, blood pressure of 144/69mmHg and respiratory rate of 42 breaths per minute. He was endotracheally intubated. Chest and abdominal radiographs demonstrated a tension pneumoperitoneum.

  7. Orion - Super Koropon(Registered Trademark) Torque/Tension Report

    Science.gov (United States)

    Hemminger, Edgar G.; McLeod, Christopher; Peil, John

    2012-01-01

    The primary objective of this testing was to obtain torque tension data for the use of Super Koropon Primer Base which was proposed for use on the Orion project. This compound is a corrosion inhibitor/sealer used on threaded fasteners and inserts as specified per NASA/JSC PRC-4004, Sealing of Joints and Faying Surfaces. Some secondary objectives of this testing, were to identify the effect on torque coefficient of several variables. This document contains the outcome of the testing.

  8. The role of muscles in tension-type headache

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Fernández-de-la-Peñas, César

    2011-01-01

    The tenderness of pericranial myofascial tissues and number of myofascial trigger points are considerably increased in patients with tension-type headache (TTH). Mechanisms responsible for the increased myofascial pain sensitivity have been studied extensively. Peripheral activation...... to prolonged nociceptive stimuli from pericranial myofascial tissues seem to be responsible for the conversion of episodic to chronic TTH. Treatment directed toward muscular factors include electromyography biofeedback, which has a documented effect in patients with TTH, as well as physiotherapy and muscle...

  9. Needle Decompression of Tension Pneumothorax with Colorimetric Capnography.

    Science.gov (United States)

    Naik, Nimesh D; Hernandez, Matthew C; Anderson, Jeff R; Ross, Erika K; Zielinski, Martin D; Aho, Johnathon M

    2017-11-01

    The success of needle decompression for tension pneumothorax is variable, and there are no objective measures assessing effective decompression. Colorimetric capnography, which detects carbon dioxide present within the pleural space, may serve as a simple test to assess effective needle decompression. Three swine underwent traumatically induced tension pneumothorax (standard of care, n = 15; standard of care with needle capnography, n = 15). Needle thoracostomy was performed with an 8-cm angiocatheter. Similarly, decompression was performed with the addition of colorimetric capnography. Subjective operator assessment of decompression was recorded and compared with true decompression, using thoracoscopic visualization for both techniques. Areas under receiver operating curves were calculated and pairwise comparison was performed to assess statistical significance (P pneumothorax, that is, the absence of any pathologic/space-occupying lesion, in 100% of cases (10 of 10 attempts). Standard of care needle decompression was detected by operators in 9 of 15 attempts (60%) and was detected in 3 of 10 attempts when tension pneumothorax was not present (30%). True decompression, under direct visualization with thoracoscopy, occurred 15 of 15 times (100%) with capnography, and 12 of 15 times (80%) without capnography. Areas under receiver operating curves were 0.65 for standard of care and 1.0 for needle capnography (P = .002). Needle decompression with colorimetric capnography provides a rapid, effective, and highly accurate method for eliminating operator bias for tension pneumothorax decompression. This may be useful for the treatment of this life-threatening condition. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  10. Oxygen Tension Regulates Human Mesenchymal Stem Cell Paracrine Functions

    OpenAIRE

    Paquet, Joseph; Deschepper, Mickael; Moya, Adrien; Logeart-Avramoglou, Delphine; Boisson-Vidal, Catherine; Petite, Hervé

    2015-01-01

    This study examined the shift of the human mesenchymal stem cell (hMSC) cytokine signature induced by oxygen tension. Conditioned media obtained from hMSCs cultured under near anoxia exhibited significantly enhanced chemotactic and proangiogenic properties and a significant decrease in the inflammatory mediator content. These results elucidate important aspects of using MSCs in regenerative medicine, contribute to improving the efficacy of such therapies, and highlight the interest in using c...

  11. Hemodynamic parameters change earlier than tissue oxygen tension in hemorrhage.

    Science.gov (United States)

    Pestel, Gunther J; Fukui, Kimiko; Kimberger, Oliver; Hager, Helmut; Kurz, Andrea; Hiltebrand, Luzius B

    2010-05-15

    Untreated hypovolemia results in impaired outcome. This study tests our hypothesis whether general hemodynamic parameters detect acute blood loss earlier than monitoring parameters of regional tissue beds. Eight pigs (23-25 kg) were anesthetized and mechanically ventilated. A pulmonary artery catheter and an arterial catheter were inserted. Tissue oxygen tension was measured with Clark-type electrodes in the jejunal and colonic wall, in the liver, and subcutaneously. Jejunal microcirculation was assessed by laser Doppler flowmetry (LDF). Intravascular volume was optimized using difference in pulse pressure (dPP) to keep dPP below 13%. Sixty minutes after preparation, baseline measurements were taken. At first, 5% of total blood volume was withdrawn, followed by another 5% increment, and then in 10% increments until death. After withdrawal of 5% of estimated blood volume, dPP increased from 6.1% +/- 3.0% to 20.8% +/- 2.7% (P < 0.01). Mean arterial pressure (MAP), mean pulmonary artery pressure (PAP) and pulmonary artery occlusion pressure (PAOP) decreased with a blood loss of 10% (P < 0.01). Cardiac output (CO) changed after a blood loss of 20% (P < 0.05). Tissue oxygen tension in central organs, and blood flow in the jejunal muscularis decreased (P < 0.05) after a blood loss of 20%. Tissue oxygen tension in the skin, and jejunal mucosa blood flow decreased (P < 0.05) after a blood loss of 40% and 50%, respectively. In this hemorrhagic pig model systemic hemodynamic parameters were more sensitive to detect acute hypovolemia than tissue oxygen tension measurements or jejunal LDF measurements. Acute blood loss was detected first by dPP. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  12. Treating tension-type headache -- an expert opinion

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Jensen, Rigmor

    2011-01-01

    INTRODUCTION: Tension-type headache (TTH) is a highly prevalent disorder with enormous costs for the individual and the society. AREAS COVERED: Nonpharmacological and pharmacological treatments are reviewed. Electromyographic (EMG) biofeedback has a documented effect in TTH, while cognitive-behav...... and clarify how treatment programs can be optimized and combined to best suit the individual patient. Frequent TTH may be difficult to treat, but an acceptable result can usually be obtained by a combination of nonpharmacological and pharmacological treatments....

  13. [Extensive injuries due to high-tension electrical current].

    Science.gov (United States)

    Tomásek, D; Königová, R; Snupárek, Z

    1989-03-01

    The authors submit a case of severe injury with high tension electric current. They emphasize the necessity of prevention of this injury which occurs most frequently when transformer stations are not adequately safeguarded, in case of inadequate protection when approaching trolley wires on the railway track, and when safety principles are not respected during work on the railway. The authors draw attention to the importance of immediate resuscitation and multidisciplinary comprehensive care.

  14. A compound crack in a pipe under tension

    International Nuclear Information System (INIS)

    Zahoor, A.

    1992-01-01

    Limit load and J-resistance curve solutions are developed for a compound crack in a pipe subjected to axial tension. The solutions are based on thick-walled cylinder assumption and the J solution can be applied with load-displacement data from one pipe test. The J-R solution can be used to assess the effect of loading type on the material's resistance to crack extension when used with previously published solution for bending moment loading. (orig.)

  15. A compound crack in a pipe under tension

    Energy Technology Data Exchange (ETDEWEB)

    Zahoor, A. (Zenith Corp., Rockville, MD (United States))

    1992-03-01

    Limit load and J-resistance curve solutions are developed for a compound crack in a pipe subjected to axial tension. The solutions are based on thick-walled cylinder assumption and the J solution can be applied with load-displacement data from one pipe test. The J-R solution can be used to assess the effect of loading type on the material's resistance to crack extension when used with previously published solution for bending moment loading. (orig.).

  16. Nutrient leaching under zero tension in a subtropical clonal eucalypt ...

    African Journals Online (AJOL)

    Little is known about the effects of residue burning or retention on nutrient leaching during the inter-rotation of clonal Eucalyptus grown on the sandy soils of subtropical Zululand, South Africa. A study compared zero-tension nutrient leaching through the top metre of soil at depths of 0.15, 0.5 and 1.0 m in an undisturbed crop ...

  17. Feminist Intersectionality Research in Communications: Origins, Contributions and Tensions

    OpenAIRE

    Carolyn M. Byerly

    2017-01-01

    The text considers some of the important work in intersectionality that has been done by critical feminist and postcolonial scholars in media and other communication fields since the 1990s, focusing particularly on the kinds of problems they have examined and their contributions to feminist theory building. The discussion also explores some of the challenges and tensions that accompany scholarship conducted from a standpoint of intersectionality.

  18. Feminist Intersectionality Research in Communications: Origins, Contributions and Tensions

    Directory of Open Access Journals (Sweden)

    Carolyn M. Byerly

    2017-06-01

    Full Text Available The text considers some of the important work in intersectionality that has been done by critical feminist and postcolonial scholars in media and other communication fields since the 1990s, focusing particularly on the kinds of problems they have examined and their contributions to feminist theory building. The discussion also explores some of the challenges and tensions that accompany scholarship conducted from a standpoint of intersectionality.

  19. 33 CFR 147.817 - Sir Douglas Morpeth Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sir Douglas Morpeth Tension Leg... HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.817 Sir Douglas Morpeth Tension Leg Platform safety zone. (a) Description. The Sir Douglas Morpeth Tension Leg Platform (Morpeth...

  20. Tensions in implementing the “energy-conservation/carbon-reduction” policy in Taiwanese culture

    International Nuclear Information System (INIS)

    Chiu, Mei-Shiu

    2013-01-01

    The aim of this study is to investigate the Taiwanese public's perceptions of tensions between the implementation of an energy policy and the practice of traditional culture. The energy policy calls for public actions to conserve energy and reduce carbon emissions. The research participants are 94 people, selected by balancing sexes, ages, and residential areas, from a wide range of vocations. The research data were collected by semi-structured interview with the participants individually. Interview questions were designed to elicit the participants' constructs, beliefs, behaviours, and tensions in relation to energy policy and traditional culture. Data analysis was performed based on a qualitative methodology by the procedure of open coding, theme finding, constant comparison, and theory generation. The analysis identifies four tensions: (1) tensions in knowledge bases between energy conservation and carbon reduction, (2) tensions in lifestyles between having and being, (3) tensions in social systems between authority and conformity, and (4) tensions in creation boundaries between technology and nature. The themes underlying the four tensions are uncertainty, pleasure, power, and control, respectively. Solutions to the four tensions may include practical knowledge, pragmatic idealism, hierarchical collaboration, and sustainable innovation. - Highlights: ► Tensions occur between energy policy and traditional culture. ► Tensions occur in knowledge, life, society, and creation in Taiwan. ► The themes of the four tensions are uncertainty, pleasure, power, and control

  1. Proceedings of the colloquium: The response of liquids to dynamic tension

    International Nuclear Information System (INIS)

    Jones, A.V.

    1978-01-01

    The contributed papers are: - Tension pulses in a liquid column; - A generalized cavitationn model for liquids; - Transmission of a tension pulse through water; - Current status of the equation of state in Lagrangian codes; - The effects of the reflection of an underwater shock at a free surface; - The calculation of the propagation of tension and recompaction waves

  2. 33 CFR 147.809 - Mars Tension Leg Platform safety zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Mars Tension Leg Platform safety... SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.809 Mars Tension Leg Platform safety zone. (a) Description. The Mars Tension Leg Platform (Mars TLP) is located at position 28°10′10.29...

  3. Tensions and Striving for Coherence in an Academic's Professional Identity Work

    Science.gov (United States)

    Arvaja, Maarit

    2018-01-01

    The emergence of 'new managerialism' in academic institutions and professions has given rise to tensions between one's professional self and work context. Such tensions often originate from a misalignment between institutional and personal values. This study builds on a dialogical approach to identity and discusses the role of inner tensions and…

  4. RESEARCH OF INFLUENCE OF FRONT TENSION AT ROLLING OF PERIODIC PROFILE IN NON-DRIVE ROLLERS

    Directory of Open Access Journals (Sweden)

    L. A. Isayevich

    2012-01-01

    Full Text Available Influence of a forward tension is theoretically investigated at a rolling of the periodic profiles used as elastic elements of spring suspension brackets. The power balance of rolling process with a tension is analyzed. Dependences for definition of a critical corner and size of its increment are received at a rolling with a forward tension.

  5. Influencia del bajo peso al nacer en el estado de salud durante el primer año

    Directory of Open Access Journals (Sweden)

    Orlando Ortiz Silva

    1997-08-01

    Full Text Available Se realizó un trabajo descriptivo-retrospectivo sobre la influencia del bajo peso al nacer en el estado de salud al año de edad en el municipio Jaruco, desde el 1ro. de enero de 1994 hasta el 31 de diciembre de 1995. Se estudiaron 2 grupos de niños: grupo 1: formado por 55 niños con peso menor de 2 500 g en el período estudiado y grupo 2: escogidos del resto de nacidos con peso superior a los 2 500 g, numéricamente similar. Se concluye que los niños con bajo peso al nacer no muestran diferencias en el desarrollo físico al año de edad, pero sí aumento en los índices de morbilidad ambulatoria y hospitalaria por infecciones respiratorias agudas, enfermedades diarreicas agudas, sepsis urinaria y anemia, así como un peso importante en la mortalidad infantil. Se recomiendan actividades de promoción y prevención para disminuir el bajo peso al nacer.A descriptive and retrospective study about the influence of low birth weight on the health status during the first year of life was conducted in the municipality of Jaruco from January 1, 1994, to december, 1995. Two gruops of children were analyzed: the first group was composed of 55 infants with less than 2 500 g in the studied period, and in the second group there was a similar amount of infants selected from the rest of those who were born with more than 2 500 g. It is concluded that infants with low birth weight show no differences in their physical development, but that there is an increase in the indexes of ambulatory and hospital morbidity resulting from respiratory tract infections, acute diarrheal diseases, urinary sepsis and anemia. It is also demonstrated the importance of promotion and prevention to reduce low birth weight.

  6. Caracterización nutricional del cactus nopal (Opuntia ficus-indica bajo diferentes tratamientos de fertilización

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Rodríguez-M.

    2011-02-01

    Full Text Available Nuestro planeta se enfrenta actualmente a grandes cambios en su ambiente natural, no sólo como consecuencia de su evolución, sino también del acelerado proceso de degradación antrópica. Dentro de este contexto se origina la necesidad de buscar soluciones que mitiguen el bajo nivel de vida del campesino, dadas las precarias condiciones de muchos de los actuales ecosistemas, que no permiten implementar los modelos tradicionales de explotación desmesurada de los recursos. El cactus nopal  (Opuntia ficus-indica ofrece ventajas en la producción animal, presentándose como una alternativa agroecológica, fácil de implementar en zonas semiáridas bajo condiciones adversas y con un mínimo de insumosagropecuarios. El  objetivo de este estudio fue evaluar el desempeño nutricional del cactus nopal bajo cuatro tipos de fertilización, mediante el análisis proximal de alimentos, implementado en el laboratorio de nutrición animal de la Universidad Pedagógica y Tecnológica de Colombia, UPTC sede Tunja, en los especímenes de cactus nopal existentes en el jardín botánico de la misma. Se utilizaron cuatro tipos de tratamientos para la fertilización: 1.Químico, 2.Orgánico, 3. Químico + Orgánico y 4.Testigo, aplicados en intervalos de veinte (20 días, por tres veces, aplicando también agua en un riego semanal; tiempo al cabo del cual se realizó la valoraciónnutricional, en donde el Tratamiento 2 (Orgánico fue el de mejor desempeño, seguido por el Tratamiento 3, luego el tratamiento 1 y, por último, el tratamiento 4 (testigo.

  7. Reflexiones sobre los sentimientos y las percepciones de las madres de recién nacidos con bajo peso

    Directory of Open Access Journals (Sweden)

    Darlene Basílio dos Santos

    2011-12-01

    Full Text Available Introducción: Para la mayoría de las mujeres, el nacimiento de un hijo se configura como un evento único, que refuerza y legitima la condición de ser mujer. Antes de nacer, el bebé es concebido, los padres se preguntan cuál es el sexo, e incluso la apariencia de que la profesión. El primero de los movimientos fetales contribuye al establecimiento de una relación de amor entre madre e hijo, que más tarde constituirán el apego materno filial. Materiales y Métodos: Es un salto cualitativo descriptivo. Según Minayo este tipo de investigación hace hincapié en la adquisición de los datos recogidos de forma descriptiva del contacto directo con la investigadora ha estudiado este fenómeno. "La investigación cualitativa el investigador guía en la comprensión del fenómeno objeto de estudio de la experiencia descrita por estar en el mundo" Resultados: Los resultados permitieron la construcción de tres categorías de análisis, que son: La hospitalización de recién nacidos con bajo peso,las estrategias para hacer frente a la hospitalización del niño en la unidad neonatal de cuidados intensivos, y obtener ayuda de enfermería como un factor facilitador para hacer frente a la hospitalización de recién nacidos con bajo peso. Discusión y Conclusiones: Con este estudio se dieron cuenta de que, al ser una madre recién nacidos con bajo peso Escort no es una condición que termina en sí mismo. Para la mujer-madre, la hospitalización del recién nacido se presenta como algo asombroso e impresionante, ya que ella soñaba con tener un bebé sano, lo que podría llevar a casa, cuidar y ejercer su papel de madre.(Rev Cuid 2011; 2(2: 168-74.Palabras clave: Enfermeria, Neonatología, Recién Nacido, Relaciones Madre-Hijo. (Fuente: DeCs BIREME.

  8. Susceptibility of 17-4PH stainless steel to stress corrosion cracking in aqueous environments by electrochemical techniques.; Estudio de la corrosion bajo tension del acero 17-4PH en medios acuosos usando tecnicas electroquimicas

    Energy Technology Data Exchange (ETDEWEB)

    Diaz S, A C [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico)

    1998-12-31

    The susceptibility of a 17-4PH type steel to Stress Corrosion Cracking (SCC) in low pressure steam turbine environments was assessed using slow strain rate test at 90 Centigrade and at 1.35x10{sup -6} seg{sup -1}. Environments tested included different concentrated solutions of NaCl, NaOH and Na{sub 2}SO{sub 4}. It was concluded that this steel is susceptible to SCC in 20 % NaCl and pH=3 and in 20 % NaCl pH=neutral but under cathodic polarisation. The electrochemical potential noise of the specimen was monitored during the test. The naturally fluctuations in potential were arise due to spontaneous brake protective film and were characteristics of the kind of corrosion like pit or stress corrosion cracking. After that using Fast Fourier Transformer (FFT) the noise data set were analyzed to obtain power spectral density plots which showed differences between general corrosion and localized corrosion. Polarization curves were carry out at two different rates and them showed the general behavior of the systems. (Author).

  9. Vacuum phase transition solves the H0 tension

    Science.gov (United States)

    Di Valentino, Eleonora; Linder, Eric V.; Melchiorri, Alessandro

    2018-02-01

    Taking the Planck cosmic microwave background data and the more direct Hubble constant measurement data as unaffected by systematic offsets, the values of the Hubble constant H0 interpreted within the Λ CDM cosmological constant and cold dark matter cosmological model are in ˜3.3 σ tension. We show that the Parker vacuum metamorphosis (VM) model, physically motivated by quantum gravitational effects and with the same number of parameters as Λ CDM , can remove the H0 tension and can give an improved fit to data (up to a mean Δ χ2=-7.5 ). It also ameliorates tensions with weak lensing data and the high redshift Lyman alpha forest data. Considering Bayesian evidence, we found in the case of the Planck data set alone positive evidence for a VM model against a cosmological constant both in the six- and nine-parameter framework. When the R16 data set is also considered, we found a strong evidence for the VM model against a cosmological constant in nine-parameter space. We separately consider a scale-dependent scaling of the gravitational lensing amplitude, such as provided by modified gravity, neutrino mass, or cold dark energy, motivated by the somewhat different cosmological parameter estimates for low and high CMB multipoles. We find that no such scale dependence is preferred.

  10. Microdamage in polycrystalline ceramics under dynamic compression and tension

    International Nuclear Information System (INIS)

    Zhang, K.S.; Zhang, D.; Feng, R.; Wu, M.S.

    2005-01-01

    In-grain microplasticity and intergranular microdamage in polycrystalline hexagonal-structure ceramics subjected to a sequence of dynamic compression and tension are studied computationally using the Voronoi polycrystal model, by which the topological heterogeneity and material anisotropy of the crystals are simulated explicitly. The constitutive modeling considers crystal plasticity by basal slip, intergranular shear damage during compression, and intergranular mode-I cracking during tension. The model parameters are calibrated with the available shock compression and spall strength data on polycrystalline α-6H silicon carbide. The numerical results show that microplasticity is a more plausible micromechanism for the inelastic response of the material under shock compression. On the other hand, the spallation behavior of the shocked material can be well predicted by intergranular mode-I microcracking during load reversal from dynamic compression to tension. The failure process and the resulting spall strength are, however, affected strongly by the intensity of local release heterogeneity induced by heterogeneous microplasticity, and by the grain-boundary shear damage during compression

  11. Sensitive and simple method for measuring wire tensions

    International Nuclear Information System (INIS)

    Atac, M.; Mishina, M.

    1982-08-01

    Measuring tension of wires in drift chambers and multiwire proportional chambers after construction is an important process because sometimes wires get loose after soldering, crimping or glueing. One needs to sort out wires which have tensions below a required minimum value to prevent electrostatic instabilities. There have been several methods reported on this subject in which the wires were excited either with sinusoidal current under magnetic field or with sinusoidal voltage electrostatically coupled to the wire, searching for a resonating frequency with which the wires vibrate mechanically. Then the vibration is detected either visually, optically or with magnetic pick-up directly touching the wires. Any of these is only applicable to the usual multiwire chamber which has open access to the wire plane. They also need fairly large excitation currents to induce a detectable vibration to the wires. Here we report a very simple method that can be used for any type of wire chamber or proportional tube system for measuring wire tension. Only a very small current is required for the wire excitation to obtain a large enough signal because it detects the induced emf voltage across a wire. A sine-wave oscillator and a digital voltmeter are sufficient devices aside from a permanent magnet to provide the magnetic field around the wire. A useful application of this method to a large system is suggested

  12. Z(2) vortices and the SU(2) string tension

    International Nuclear Information System (INIS)

    Goepfert, M.

    1981-01-01

    Topologically determined Z(2) variables in pure SU(2) lattice gauge theory are discussed. They count the number of 'vortex souls'. The high temperature expansion for the corresponding Z(2) loops is examined. They obey an area law. The coefficient of the area is shown to be equal to the string tension to all orders of the high temperature expansion. This shows that the string tension is determined by the probability distribution of the vortex souls, at least in the high temperature region. The dependence of the string tension α(β,h) on an external field h that is coupled to the Z(2) field strength is calculated to lowest order of the high temperature expansion. In this approximation, α(β,h) is determined by the free energy of a 2-dimensional Ising model in an external magnetic field 1/2log(β/4tanhh) at an inverse temperature 1/2log3/4π = 0.429. (orig.)

  13. The environmental factors as reason for emotional tension

    Science.gov (United States)

    Prisniakova, L.

    The information from environment is a reason of activation of an organism, it calls abrupt changings in nervous processes and it offers emotions. One part of emotions organizes and supports activity, others disorganize it. In fields of perception, of making decision, fulfilment of operatings, of learning the emotional excitation raises the level of carrying-out more easy problems and reduces of more difficult one. The report are presented the outcomes of quantitative determination of a level of emotional tension on successful activity. The inverse of the sign of influencing on efficiency of activity of the man is detected. The action of the emotional tension on efficiency of professional work was demonstrated to have similarly to influencing of motivation according to the law Yerkes -Dodson. The report introduces a mathematical model of connection of successful activity and motivations or the emotional tension. Introduced in the report the outcomes can serve the theoretical idealized basis of the quantitative characteristics of an estimation of activity of astronauts in conditions of the emotional factors at a phase of selection

  14. Tension pneumothorax secondary to automatic mechanical compression decompression device.

    Science.gov (United States)

    Hutchings, A C; Darcy, K J; Cumberbatch, G L A

    2009-02-01

    The details are presented of the first published case of a tension pneumothorax induced by an automatic compression-decompression (ACD) device during cardiac arrest. An elderly patient collapsed with back pain and, on arrival of the crew, was in pulseless electrical activity (PEA) arrest. He was promptly intubated and correct placement of the endotracheal tube was confirmed by noting equal air entry bilaterally and the ACD device applied. On the way to the hospital he was noted to have absent breath sounds on the left without any change in the position of the endotracheal tube. Needle decompression of the left chest caused a hiss of air but the patient remained in PEA. Intercostal drain insertion in the emergency department released a large quantity of air from his left chest but without any change in his condition. Post-mortem examination revealed a ruptured abdominal aortic aneurysm as the cause of death. Multiple left rib fractures and a left lung laceration secondary to the use of the ACD device were also noted, although the pathologist felt that the tension pneumothorax had not contributed to the patient's death. It is recommended that a simple or tension pneumothorax should be considered when there is unilateral absence of breath sounds in addition to endobronchial intubation if an ACD device is being used.

  15. Liquid metal actuation by electrical control of interfacial tension

    Energy Technology Data Exchange (ETDEWEB)

    Eaker, Collin B.; Dickey, Michael D., E-mail: michael-dickey@ncsu.edu [Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695 (United States)

    2016-09-15

    By combining metallic electrical conductivity with low viscosity, liquid metals and liquid metal alloys offer new and exciting opportunities to serve as reconfigurable components of electronic, microfluidic, and electromagnetic devices. Here, we review the physics and applications of techniques that utilize voltage to manipulate the interfacial tension of liquid metals; such techniques include electrocapillarity, continuous electrowetting, electrowetting-on-dielectric, and electrochemistry. These techniques lower the interfacial tension between liquid metals and a surrounding electrolyte by driving charged species (or in the case of electrochemistry, chemical species) to the interface. The techniques are useful for manipulating and actuating liquid metals at sub-mm length scales where interfacial forces dominate. We focus on metals and alloys that are liquid near or below room temperature (mercury, gallium, and gallium-based alloys). The review includes discussion of mercury—despite its toxicity—because it has been utilized in numerous applications and it offers a way of introducing several phenomena without the complications associated with the oxide layer that forms on gallium and its alloys. The review focuses on the advantages, applications, opportunities, challenges, and limitations of utilizing voltage to control interfacial tension as a method to manipulate liquid metals.

  16. A micro surface tension pump (MISPU) in a glass microchip.

    Science.gov (United States)

    Peng, Xing Yue Larry

    2011-01-07

    A non-membrane micro surface tension pump (MISPU) was fabricated on a glass microchip by one-step glass etching. It needs no material other than glass and is driven by digital gas pressure. The MISPU can be seen working like a piston pump inside the glass microchip under a microscope. The design of the valves (MISVA) and pistons (MISTON) was based on the surface tension theory of the micro surface tension alveolus (MISTA). The digital gas pressure controls the moving gas-liquid interface to open or close the input and output MISVAs to refill or drive the MISTON for pumping a liquid. Without any moving parts, a MISPU is a kind of long-lasting micro pump for micro chips that does not lose its water pumping efficiency over a 20-day period. The volumetric pump output varied from 0 to 10 nl s(-1) when the pump cycle time decreased from 5 min to 15 s. The pump head pressure was 1 kPa.

  17. Chinese Herbal Therapy for Chronic Tension-Type Headache

    Directory of Open Access Journals (Sweden)

    YanQing Tong

    2015-01-01

    Full Text Available Objective. To investigate the effects of Chinese herbal therapy on chronic tension-type headache. Method. 132 patients with chronic tension-type headache were enrolled in the study. All patients filled in headache questionnaire at baseline phase and 4, 8, and 12 weeks after baseline. As an alternative therapeutic method, the patients were orally administrated Chinese herbal concoction for ten days. Therapeutic effects were evaluated during 12 weeks of followup. Result. In the primary outcome analysis, mean headache scores were significantly lower in the group. Scores fell by 25%–40% during 12 weeks of followup. Patients fared significantly well for most secondary outcome measures. From baseline to 4–12 weeks of followup, the number of days with headache decreased by 6.8–9.5 days. Duration of each attack also significantly (P < 0.05 shortened from 5.3 hours at 4 weeks to 4.9 hours after 8 weeks of followup. Days with medication per four weeks at followup were lower than those at the baseline. The differences were significant (P < 0.05, 0.01 for all end points. Days with medication fell by 56.6% at 12 weeks. Conclusion. The study has provided evidence that Chinese herbal therapy can be clinically useful for the treatment of chronic tension-type headache.

  18. About the choice of tension for canvas paintings

    Directory of Open Access Journals (Sweden)

    Antonio Iaccarino Idelson

    2009-10-01

    Full Text Available The choice of the value of tension for a canvas painting is crucial for its future life, but tradition has handed us methods based on intuition that do not allow us comparing the results of different choices. Since the 1950es it is possible to measure the force used for stretching a painting, but this is very rarely done. This paper describes the evolution of the approach to the problem and points out the results of recent research and changes in attitude.Le choix de la valeur de tension pour une peinture sur toile est crucial pour sa future conservation, mais la tradition nous a transmis des méthodes fondées sur l’intuition qui ne nous permettent pas de comparer les effets des différents choix. Depuis les années 1950 il est possible de mesurer la force de tension choisie pour une peinture, mais ce la est fait très rarement. Cet article décrit l’évolution de l’approche à ce problème et souligne les résultats de récents recherches et changements d’attitude.      

  19. Diffusive intergranular cavity growth in creep in tension and torsion

    International Nuclear Information System (INIS)

    Stanzl, S.E.; Argon, A.S.; Tschegg, E.K.

    1983-01-01

    Creep experiments were performed at 500 C in tension and torsion on high conductivity copper tubes with a uniform initial coverage of implanted water vapor bubbles on all grain boundaries. No significant differences were found in the times to fracture over a wide stress range when the results were correlated according to the maximum principal tensile stress in the two fields. The results indicate that the cavities grow in a crack-like mode but at one tenth the rate predicted from the theoretical model of Pharr and Nix. This difference is attributed partly to load shedding from boundaries normal to the maximum principal tensile stress to slanted boundaries, and partly to a lack of knowledge about th surface diffusion constant. The results indicate further that the contribution to intergranular cavity growth by power-law creep in negligible in comparison to the contribution by diffusional flow. Complementary tension and torsion experiments performed in initially uncavitated samples results in shorter creep lives in torsion than in tension due to more effective cavity nucleation in the former. The times to fracture in both of these cases obey Monkman and Grant's law, indicating the presence of constraints on growth by the lagging deformations by power-law creep in the surroundings of the cavitating isolated grain facets

  20. Precipitating and relieving factors of migraine versus tension type headache

    Directory of Open Access Journals (Sweden)

    Haque Badrul

    2012-08-01

    Full Text Available Abstract Background To determine the differences of precipitating and relieving factors between migraine and tension type headache. Methods This is a cross sectional study. We retrospectively reviewed the records of 250 migraine patients and 250 patients diagnosed as tension type headache from the specialized headache clinic in Dept. of Neurology, Dhaka Medical College Hospital. Data were collected through a predesigned questionnaire containing information on age, sex, social status and a predetermined list of precipitating and relieving factors. Results In this study, the female patients predominated (67%. Most of the patients were within 21–30 years age group (58.6%. About 58% of them belonged to middle class families. The common precipitating factors like stress, anxiety, activity, journey, reading, cold and warm were well distributed among both the migraine and tension type headache (TTH patients. But significant difference was demonstrated for fatigue (p  Conclusion The most frequent precipitating factors for headache appear to be identical for both migraine and TTH patients. Even though some factors like fatigue, sleep deprivation, sunlight and food significantly precipitate migraine and drug, massage are effective maneuver for relieving pain among migrianeurs.

  1. Estrés Materno y Configuración Familiar: Estudio comparativo en Familias Chilenas Monoparentales y Nucleares de bajos ingresos

    OpenAIRE

    Olhaberry, Marcia; Pontificia Universidad Católica de Chile; Farkas, Chamarrita

    2012-01-01

    Los estudios sobre estrés materno durante la crianza infantil han considerado variables contextuales para explicarlo. El nivel socioeconómico, así como la configuración familiar han sido variables relevantes, asociándose monoparentalidad en familias de bajos ingresos a mayores niveles de estrés materno. Se estudian los niveles de estrés materno en familias chilenas nucleares y monoparentales de N.S.E. bajo, considerando el estrés en distintas dimensiones, asociado al rol materno, a la interac...

  2. Producción de hortalizas bajo invernaderos (fitotoldos), en la mejora de la alimentación familiar en zonas Altoandinas, Melgar, Puno Perú

    OpenAIRE

    Morocco Pilco,Natali Beatriz

    2015-01-01

    El trabajo se desarrolló en los distritos de Umachiri, Cupi y Macari, provincia de Melgar, Región Puno, Perú, sobre los 3900 m.s.n.m.; con el objetivo de determinar los beneficios de la producción de hortalizas bajo invernaderos (fitotoldos) en la alimentación familiar. Se seleccionaron 25 familias para realizar las determinaciones en campo. La producción de hortalizas bajo invernadero (fitotoldos) en zonas alto andinas, permite generar disponibilidad y acesso a alimentos diversificados y nut...

  3. Influence of specimen type and reinforcement on measured tension-tension fatigue life of unidirectional GFRP laminates

    DEFF Research Database (Denmark)

    Korkiakoski, Samuli; Brøndsted, Povl; Sarlin, Essi

    2016-01-01

    It is well known that standardised tension-tension fatigue test specimens of unidirectional (UD) glass-fibre-reinforced plastics (GFRP) laminates tend to fail at end tabs. The true fatigue life is then underestimated. The first objective of this study was to find for UD GFRP laminates a test...... specimen that fails in the gauge section. The second objective was to compare fatigue performance of two laminates, one having a newly developed UD powder-bound fabric as a reinforcement and the other having a quasi-UD stitched non-crimp fabric as a reinforcement. In the first phase, a rectangular specimen...... in accordance with the ISO 527-5 standard and two slightly different dog-bone shaped specimens were evaluated by means of finite element modelling. Subsequent comparative fatigue tests were performed for the laminates with the three specimen types. The results showed that the test specimen type has...

  4. Experimental Study of Axially Tension Cold Formed Steel Channel Members

    Science.gov (United States)

    Apriani, Widya; Lubis, Fadrizal; Angraini, Muthia

    2017-12-01

    Experimental testing is commonly used as one of the steps to determine the cause of the collapse of a building structure. The collapse of structures can be due to low quality materials. Although material samples have passed laboratory tests and the existing technical specifications have been met but there may be undetected defects and known material after failure. In this paper will be presented Experimental Testing of Axially Tension Cold Formed Steel Channel Members to determine the cause of the collapse of a building roof truss x in Pekanbaru. Test of tensile strength material cold formed channel sections was performed to obtain the main characteristics of Cold Formed steel material, namely ultimate tensile strength loads that can be held by members and the yield stress possessed by channel sections used in construction. Analysis of axially tension cold formed steel channel section presents in this paper was conducted through experimental study based on specificationsAnnualBook of ASTM Standards: Metal Test methods and Analitical Procedures, Section 3 (1991). The result of capacity loads experimental test was compared with design based on SNI 03-7971-2013standard of Indonesia for the design of cold formed steel structural members. The results of the yield stress of the material will be seen against the minimum allowable allowable stress range. After the test, the percentace of ultimate axial tension capacity theory has a result that is 16.46% larger than the ultimate axial tension capacity experimental. When compared with the load that must be borne 5.673 kN/m it can be concluded that 2 specimens do not meet. Yield stress of member has fulfilled requirement that wass bigger than 550 MPa. Based on the curve obtained ultimate axial tension capacity theory, results greater than experimental. The greatest voltage value (fu) is achieved under the same conditions as its yield stress. For this specimen with a melting voltage value fy = 571.5068 MPa has fulfilled the

  5. Tourniquet pressures: strap width and tensioning system widths.

    Science.gov (United States)

    Wall, Piper L; Coughlin, Ohmar; Rometti, Mary; Birkholz, Sarah; Gildemaster, Yvonne; Grulke, Lisa; Sahr, Sheryl; Buising, Charisse M

    2014-01-01

    Pressure distribution over tourniquet width is a determinant of pressure needed for arterial occlusion. Different width tensioning systems could result in arterial occlusion pressure differences among nonelastic strap designs of equal width. Ratcheting Medical Tourniquets (RMTs; m2 inc., http://www.ratcheting buckles.com) with a 1.9 cm-wide (Tactical RMT) or 2.3 cm-wide (Mass Casualty RMT) ladder were directly compared (16 recipients, 16 thighs and 16 upper arms for each tourniquetx2). Then, RMTs were retrospectively compared with the windlass Combat Application Tourniquet (C-A-T ["CAT"], http://combattourniquet.com) with a 2.5 cm-wide internal tensioning strap. Pressure was measured with an air-filled No. 1 neonatal blood pressure cuff under each 3.8 cm-wide tourniquet. RMT circumferential pressure distribution was not uniform. Tactical RMT pressures were not higher, and there were no differences between the RMTs in the effectiveness, ease of use ("97% easy"), or discomfort. However, a difference did occur regarding tooth skipping of the pawl during ratchet advancement: it occurred in 1 of 64 Tactical RMT applications versus 27 of 64 Mass Casualty RMT applications. CAT and RMT occlusion pressures were frequently over 300 mmHg. RMT arm occlusion pressures (175-397 mmHg), however, were lower than RMT thigh occlusion pressures (197-562 mmHg). RMT effectiveness was better with 99% reached occlusion and 1% lost occlusion over 1 minute versus the CAT with 95% reached occlusion and 28% lost occlusion over 1 minute. RMT muscle tension changes (up to 232 mmHg) and pressure losses over 1 minute (24±11 mmHg arm under strap to 40±12 mmHg thigh under ladder) suggest more occlusion losses may have occurred if tourniquet duration was extended. The narrower tensioning system Tactical RMT has better performance characteristics than the Mass Casualty RMT. The 3.8 cm-wide RMTs have some pressure and effectiveness similarities and differences compared with the CAT. Clinically

  6. Soil tension mediates isotope fractionation during soil water evaporation

    Science.gov (United States)

    Gaj, Marcel; McDonnell, Jeffrey

    2017-04-01

    Isotope tracing of the water cycle is increasing in its use and usefulness. Many new studies are extracting soil waters and relating these to streamflow, groundwater recharge and plant transpiration. Nevertheless, unlike isotope fractionation factors from open water bodies, soil water fractionation factors are poorly understood and until now, only empirically derived. In contrast to open water evaporation where temperature, humidity and vapor pressure gradient define fractionation (as codified in the well-known Craig and Gordon model), soil water evaporation includes additionally, fractionation by matrix effects. There is yet no physical explanation of kinetic and equilibrium fraction from soil water within the soil profile. Here we present a simple laboratory experiment with four admixtures of soil grain size (from sand to silt to clay). Oven-dried samples were spiked with water of known isotopic composition at different soil water contents. Soils were then stored in sealed bags and the headspace filled with dry air and allowed to equilibrate for 24hours. Isotopic analysis of the headspace vapor was done with a Los Gatos Inc. water vapor isotope analyzer. Soil water potential of subsamples were measured with a water potential meter. We show for the first time that soil tension controls isotope fractionation in the resident soil water. Below a Pf 3.5 the δ-values of 18O and 2H of the headspace vapor is more positive and increases with increasing soil water potential. Surprisingly, we find that the relationship between soil tension and equilibrium fractionation is independent of soil type. However, δ-values of each soil type plot along a distinct evaporation line. These results indicate that equilibrium fractionation is affected by soil tension in addition to temperature. Therefore, at high soil water tension (under dry conditions) equilibrium fractionation is not consistent with current empirical formulations that ignore these effects. These findings may have

  7. Cataluña y el Bajo Ampurdán en la obra de Juan Carandell Pericay

    OpenAIRE

    Naranjo-Ramírez, J.; López Ontiveros, Antonio

    2007-01-01

    En el contexto de un estudio general y completo de la obra del geólogo y geógrafo Juan Carandell, se aporta una aproximación al papel que Cataluña –y más concretamente el Bajo Ampurdán-, su geografía y sus gentes juegan en la vida y en la obra de nuestro autor. Con una mirada amplia y generalizadora se recuerdan las aportaciones y trabajos dedicados a estas tierras bajoampurdanesas, acerca de las cuales se hace un resumen y una valoración científica. Todo ello permite a su vez detectar la alt...

  8. Proyecto Turístico de Cabañas de Bajo Impacto Ambiental en la Paz Km70

    OpenAIRE

    Quito, Natali

    2015-01-01

    El método que servirá de base para la realización del presente proyecto turístico de “Cabañas de Bajo Impacto Ambiental en la Paz Km70”, es el inductivo, por cuanto se efectuará los análisis de los temas mencionados en el esquema de contenidos, también me apoyaré en la investigación exploratoria de campo debido a que se deben realizar visitas al lugar, ayudándome en las técnicas de investigación como son: observación, entrevistas, grupos focales, así también se empleará la investigación bibli...

  9. Fotogrametría de bajo coste para la modelización de edificios históricos

    Directory of Open Access Journals (Sweden)

    José Luis Pérez García

    2011-04-01

    Full Text Available En los últimos tiempos las metodologías y herramientas utilizadas para el estudio y la documentación del patrimonio histórico han sufrido un importante avance al disponer de un mayor abanico de posibilidades para abordar estas tareas. Sin embargo, algunas de estas nuevas posibilidades, tales como las estaciones fotogramétricas digitales o el sistema láser escáner, si bien facilitan y mejoran de manera importante los trabajos y productos obtenidos, tienen un coste bastante elevado, que en muchos casos no permiten su utilización. En este trabajo se presentan diferentes técnicas fotogramétricas de bajo coste, que permiten obtener productos con precisiones aceptables y muy interesantes para el estudio, la documentación y modelización de documentos históricos.

  10. Pérdidas de suelo y nutrientes bajo diferentes coberturas vegetales en la zona Andina de Colombia

    Directory of Open Access Journals (Sweden)

    J. Alexander Rodríguez

    2009-07-01

    Full Text Available El estudio se realizó en la reserva natural El Ciprés, ubicada en la vereda Bellavista, municipio de El Dovio (Valle del Cauca. La vereda se encuentra en la zona Andina de la cordillera occidental, en el departamento del Valle del Cauca, entre 1700 y 1800 m.s.n.m., con una temperatura promedio de 18 °C. Según la clasificación climática de Holdridge, corresponde a una zona de bosque húmedo Montano Bajo, con una precipitación promedio entre 2500 y 2700 mm/año, una humedad relativa de 90% y una pendiente del suelo de 62%. Las mediciones se hicieron en parcelas de escorrentía de 32 m² cada una y siete tipos de coberturas: guadua (Guadua angustifolia Kunth, bosque secundario, pastura (Brachiaria decumbens, café (Coffea arabica; banco de proteína (Trichanthera gigantea, caña forrajera (Saccharum officinarum y cultivo limpio conformado por yuca (Manihot esculenta, maíz (Zea mays y arracacha (Arracacia zanthorrhiza Brancroft. Para la evaluación se midieron las pérdidas de suelo y los nutrientes calcio, magnesio, potasio y fósforo en un periodo de 7 meses. Los resultados mostraron diferencias (P < 0.05 entre las coberturas evaluadas. Las pérdidas más altas de suelo y nutrientes ocurrieron bajo cultivos limpios (2.61 t/ha y las más bajas en guadua (0.08 t/ha. Estos resultados sugieren ventajas de los bosques de guadua en esta zona de Colombia, ya que además de contribuir a la conservación de los suelos y al mantenimiento de la fertilidad, es una alternativa económica complementaria para los productores rurales a partir de su manejo y aprovechamiento.

  11. FRECUENCIA DE HEMOPARÁSITOS EN BOVINOS DEL BAJO CAUCA Y ALTO SAN JORGE, 2000-2005

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    Mariana Herrera

    2008-12-01

    Full Text Available Objetivo. Determinar la frecuencia de hemoparásitos en los bovinos evaluados por microscopía directa. Materiales y métodos. Se aplicó un modelo epidemiológico cuyo diseño de investigación fue transeccional de tipo descriptivo retrospectivo transversal. Se analizó la totalidad de los datos de los últimos 5 años, proporcionados por el laboratorio Lavebac que presta su servicio a las regiones del Bajo Cauca Antioqueño y Córdoba. Se realizó un análisis de tendencias por el tipo de parásito, sistema de explotación, procedencia y época climática; seguido de un análisis comparativo de asociación utilizando la razón de disparidad (RD y el X2, mediante el programa EPI-INFO versión 3.3. Resultados. Se encontró una frecuencia hemoparasitaria del 22.5%, y de estos el 59.3% correspondió a Anaplasma sp, el 3.1% a Babesia sp y para Trypanosoma sp 30.9%. La región con mayor frecuencia hemoparasitaria fue Bajo Cauca (14%; los diagnósticos positivos fueron realizados con mayor frecuencia en época seca (14.9%, en la que se detectó mayor proporción de infección por Anaplasma sp. Conclusiones. Los resultados dan una aproximación a la frecuencia y distribución de Trypanosoma sp, Babesia sp y Anaplasma sp en dos zonas ganaderas de Colombia, en donde durante la época seca se encontró un mayor porcentaje de infección, y de los agentes hemoparasitarios Anaplasma sp es el más frecuente.

  12. Pérdidas de suelo y nutrientes bajo diferentes coberturas vegetales en la zona Andina de Colombia

    Directory of Open Access Journals (Sweden)

    Rodríguez José Alexander

    2009-09-01

    Full Text Available El estudio se realizó en la reserva natural El Ciprés, ubicada en la vereda Bellavista, municipio de El Dovio (Valle del Cauca. La vereda se encuentra en la zona Andina de la cordillera occidental, en el departamento del Valle del Cauca, entre 1700 y 1800 m.s.n.m., con una temperatura promedio de 18 °C. Según la clasificación climática de Holdridge, corresponde a una zona de bosque húmedo Montano Bajo, con una precipitación promedio entre 2500 y 2700 mm/año, una humedad relativa de 90% y una pendiente del suelo de 62%. Las mediciones se hicieron en parcelas de escorrentía de 32 m2 cada una y siete tipos de coberturas: guadua (Guadua angustifolia Kunth, bosque secundario, pastura (Brachiaria decumbens, café (Coffea arabica; banco de proteína (Trichanthera gigantea, caña forrajera (Saccharum officinarum y cultivo limpio conformado por yuca (Manihot esculenta, maíz (Zea mays y arracacha (Arracacia zanthorrhiza Brancroft. Para la evaluación se midieron las pérdidas de suelo y los nutrientes calcio, magnesio, potasio y fósforo en un periodo de 7 meses. Los resultados mostraron diferencias (P < 0.05 entre las coberturas evaluadas. Las pérdidas más altas de suelo y nutrientes ocurrieron bajo cultivos limpios (2.61 t/ha y las más bajas en guadua (0.08 t/ha. Estos resultados sugieren ventajas de los bosques de guadua en esta zona de Colombia, ya que además de contribuir a la conservación de los suelos y al mantenimiento de la fertilidad, es una alternativa económica complementaria para los productores rurales a partir de su manejo y aprovechamiento.

  13. Relationship between viral and prokaryotic abundance on the Bajo O’Higgins 1 Seamount (Humboldt Current System off Chile

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    Oscar E. Chiang

    2007-03-01

    Full Text Available There is little known about the ecology of microbial communities living in the water column over seamounts. Here, for the first time, the spatial distribution and abundance of virus-like particles (VLP are described over a seamount. The association between VLP distribution, prokaryotic abundance, and environmental variables is also analyzed. Sampling was conducted in December 2004 on the Bajo O’Higgins 1 seamount (32°54’S, 73°53’W located in the Humboldt Current System off Chile. A oxygen minimum layer (OMZ was clearly present between 130 and 280 m in the water column over the seamount. Water samples were taken with Niskin bottles at 10 oceanographic stations over the seamount at depths of 5, 20, 50, 75, 100, and 150 m and at the benthic boundary layer (BBL; 5-12 m over the sediments. Temperature, salinity, oxygen, chlorophyll , and phaeopigments were measured at each station. Viral and prokaryotic abundances were determined with fluorochrome SYBR Green I. Viral abundance ranged from 1.53 x 109 VLP L-1 - 16.48 x 109 VLP L-1, whereas prokaryotic abundance ranged from 1.78 x 10 8 cell L-1 - 14.91 x 108 cell L-1. The virus-like particle/prokaryote ratio varied widely among the analyzed layers (i.e. surface, OMZ, and BBL, probably due to the presence of different prokaryotic and viral assemblages in each layer. Our results indicate that the environmental conditions, mainly the concentration of dissolved oxygen in the water column over Bajo O’Higgins 1 seamount, shape the association between viral and prokaryotic abundance.

  14. Atención y Memoria en estudiantes con bajo rendimiento académico. Un estudio exploratorio

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    Nicolás Parra-Bolaños

    2017-02-01

    Full Text Available Resumen: Actualmente, diversos estudios evidencian la relevancia de los procesos neuropsicológicos como Atención y Memoria en el proceso de aprendizaje del alumnado. El objetivo de esta investigación es analizar el nivel de atención y memoria en estudiantes colombianos con bajo rendimiento académico. Método: La muestra (N=29, M=9.72, SD=2.78 está compuesta por escolares de Educación Primaria con bajo rendimiento académico. Las pruebas administradas fueron la Prueba de Ejecución Continua Visual y Auditiva y la Figura Compleja de Rey. Resultados: El análisis muestra que existen correlaciones significativas positivas moderadas entre atención visual, atención auditiva y memoria visual; no existen diferencias significativas entre atención visual, atención auditiva y memoria visual. Conclusiones: Estos resultados son relevantes para la elaboración de programas de intervención que mejoren el rendimiento académico mediante el diseño de estrategias aplicables a cualquier asignatura educativa. Attention and Memory in students with low academic performance. An exploratory study Abstract: Currently, several studies show the relevance of the neuropsychological processes such as attention and memory in the process of student learning. The overall objective of this research is to analyze the level of attention and memory in Colombian students with poor academic performance. Method: The sample (N= 29, M=9.72, SD=2.78 consisted students with to poor academic performance. It was administered the Visual and Auditory Continuous Performance and Rey Complex Figure Test. Results: The analysis show significant correlations between visual attention, auditory attention, and visual memory; no significant differences between visual attention, visual memory and auditory attention in the study sample. Conclusions: These results are relevant to the development of programs intervention to improve performance academic.

  15. EXPERIENCE WITH THE OPEN TENSION-FREE HERNIA REPAIR

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    Slavko Rakovec

    2002-03-01

    Full Text Available Background. All old techniques of herniorrhaphy involve approximation of tissues under tension, which accounts for their unreliability. Therefore the recovery time is long and the recurrence rate unacceptably high. The new methods using a mesh patch of polypropylene allow for a tensionfree repair, which is much more reliable. So they are associated with a shorter recovery time and carry a low probability of recurrence. The tension-free repair can be accomplished in an open manner, by placing the mesh through an open incision, or by the endoscopic technique, which involves placing the mesh from within by laparoscopic instruments. The open tension-free procedures can be performed with the use of stitches (according to Lichtenstein or without them (sutureless techniques. Stitching the mesh may cause problems due to maldistribution of tension between the mesh and the patient’s tissues, the occurrence of neuralgia or the development of inflammatory granuloma. Therefore sutureless procedures are increasingly performed. They usually require, besides the use of a mesh patch, also the use of a dart plug made of the same material.Methods. The open tension-free methods of hernia repair have been used at our Department since 1994. The first 77 operations were performed by Lichtenstein technique. The mean postoperative hospital stay was 3.4 days and the mean work restriction period was 3 weeks. In the middle of the year 1995, we shifted to suturless technique. By the end of the year 2000, we had performed 768 operations. The average postoperative hospital stay was 1.2 days and the average recovery time was 10 days.Results. In the first group of 77 hernia repairs performed by the Lichtenstein procedure serious complications were noted in six patients: bleeding in one, long-lasting neuralgia in two, and purulent granuloma, appearing long after discharge from the hospital, in three. There were no recurrences. In the second group of 768 hernia repairs

  16. Rein tension acceptance in young horses in a voluntary test situation.

    Science.gov (United States)

    Christensen, J W; Zharkikh, T L; Antoine, A; Malmkvist, J

    2011-03-01

    During riding, horses are frequently exposed to pressure from the rider, e.g. through the bit and reins, but few studies have investigated at which point rein tension becomes uncomfortable for the horse. To investigate how much rein tension young inexperienced horses are willing to accept in order to obtain a food reward; whether the tension acceptance changes during 3 consecutive test days; and whether rein tension correlates with the expression of conflict behaviour and heart rate. Pressure-naïve horses will apply only little rein tension in the first voluntary trial, but their acceptance will gradually increase. High levels of rein tension will lead to expression of conflict behaviour and increases in heart rate. Fifteen 2-year-old, bridle-naïve mares were encouraged to stretch their head forward (across a 0.95 m high metal bar) to obtain a food reward in a voluntary test situation. On each test day, each horse was exposed to 2 control sessions (loose reins), an intermediate and a short rein session (1 min/session). Rein tension, heart rate and behaviour were recorded. The horses applied significantly more tension on the first day (mean rein tension: 10.2 N), compared to the second and third test day (Day 2: 6.0 and Day 3: 5.7 N). The horses showed significantly more conflict behaviour in the short rein treatment. There was no treatment effect on heart rate. The horses applied the highest rein tension on the first day, and apparently learned to avoid the tension, rather than habituate to it. Rein tension correlated with expression of conflict behaviour, indicating that the horses found the tension aversive. Further studies should focus on the correlation between rein tension and conflict behaviour in ridden horses. © 2010 EVJ Ltd.

  17. Aversive tension in female adolescents with Anorexia Nervosa: a controlled ecological momentary assessment using smartphones.

    Science.gov (United States)

    Kolar, David R; Hammerle, Florian; Jenetzky, Ekkehart; Huss, Michael; Bürger, Arne

    2016-04-12

    Current models of Anorexia Nervosa (AN) emphasize the role of emotion regulation. Aversive tension, described as a state of intense arousal and negative valence, is considered to be a link between emotional events and disordered eating. Recent research focused only on adult patients, and mainly general emotion regulation traits were studied. However, the momentary occurrence of aversive tension, particularly in adolescents with AN, has not been previously studied. 20 female adolescents with AN in outpatient treatment and 20 healthy adolescents aged 12 to 19 years participated in an ecological momentary assessment using their smartphones. Current states of aversive tension and events were assessed hourly for two consecutive weekdays. Mean and maximum values of aversive tension were compared. Multilevel analyses were computed to test the influence of time and reported events on aversive tension. The effect of reported events on subsequent changes of aversive tension in patients with AN were additionally tested in a multilevel model. AN patients showed higher mean and maximum levels of aversive tension. In a multilevel model, reported food intake was associated with higher levels of aversive tension in the AN group, whereas reported school or sport-related events were not linked to specific states of aversive tension. After food intake, subsequent increases of aversive tension were diminished and decreases of aversive tension were induced in adolescents with AN. Aversive tension may play a substantial role in the psychopathology of AN, particular in relation with food intake. Therefore, treatment should consider aversive tension as a possible intervening variable during refeeding. Our findings encourage further research on aversive tension and its link to disordered eating. German register of clinical trials (DRKS): DRKS00005228 (Date of registration: September 2, 2013).

  18. Bajo vientre: Representaciones de la sexualidad en la cultura y el arte contemporáneo. El arte impuro: Entre lo público y lo privado

    OpenAIRE

    Cuéllar, Carlos A.

    1998-01-01

    Cuéllar, CA. (1998). Bajo vientre: Representaciones de la sexualidad en la cultura y el arte contemporáneo. El arte impuro: Entre lo público y lo privado. Banda aparte. (11):89-89. http://hdl.handle.net/10251/43155. 89 89 11

  19. Comportamiento del índice de bajo peso al nacer en el Policlínico Docente Cerro durante los años 2009-2010

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    Ramona Moraima Torres Zulueta

    Full Text Available Introducción: el bajo peso al nacerconstituye el índice predictivo más importante de la mortalidad infantil y se plantea que es 20 veces mayor que en el recién nacido con peso adecuado. Objetivo: comparar el comportamiento del índice de bajo peso al nacer en recién nacidos de un Policlínico durante los años 2009 y 2010. Método: se realizó un estudio comparativo de tipo descriptivo en el Policlínico Universitario Cerro, en la provincia La Habana, durante los años 2009 y 2010. El Universo estuvo constituido por los 350 recién nacidos vivos en el 2009 y los 318 en el 2010, y la muestra estuvo conformada por 23 niños con bajo peso al nacer en el 2009 y por 21 en el 2010. Se revisaron las historias obstétricas de las madres y se identificaron algunas variables socio-demográficas. Resultados: en ambos años estudiados la edad materna de mayor bajo peso al nacer fue de 20 a 34 años, con 73,9 y 80,9 %. Los factores de riesgo que se asociaron al bajo peso fueron: el hábito de fumar, que predominó en ambos años de estudio, representado por un 60,8 % en 2009 y por un 61,9 % en el 2010; el trastorno hipertensivo, con un 35 % en el año 2010 y un 27,7 % en el año 2009, y en ambos años fue superior en el grupo de gestantes con hipertensión arterial crónica. La anemia aumentó considerablemente en el 2010 en un 80,9 %, comparado con un 69,5 % en el año 2009. Conclusiones: el bajo peso al nacer resultó más frecuente en las gestantes de 20 a 34 años. Los factores de riesgo asociados al bajo peso al nacer con mayor frecuencia fueron: la anemia, el hábito de fumar y los trastornos hipertensivos.

  20. Oxygen tension during biofilm growth influences the efficacy antimicrobial agents

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    Raquel Pippi ANTONIAZZI

    Full Text Available Abstract Objective To compare the antimicrobial efficacy of a 0.12% chlorhexidine (CHX and herbal green tea (Camellia sinensis solution on established biofilms formed at different oxygen tensions in an in situ model. Method Twenty-five dental students were eligible for the study. In situ devices with standardized enamel specimens (ES facing the palatal and buccal sides were inserted in the mouths of volunteers for a 7 day period. No agent was applied during the first four days. From the fifth day onward, both agents were applied to the test ES group and no agent was applied to the control ES group. After 7 days the ES fragments were removed from the devices, sonicated, plated on agar, and incubated for 24 h at 37 °C to determine and quantify the colony forming units (CFUs. Result CHX had significantly higher efficacy compared to green tea on the buccal (1330 vs. 2170 CFU/µL and palatal (2250 vs. 2520 CFU/µL ES. In addition, intragroup comparisons showed significantly higher efficacy in buccal ES over palatal ES (1330 vs. 2250 CFU/µL for CHX and 2170 vs, 2520 CFU/µL for CV for both solutions. Analysis of the ES controls showed significantly higher biofilm formation in palatal ES compared to buccal ES. Conclusion CHX has higher efficacy than green tea on 4-day biofilms. The efficacy of both agents was reduced for biofilms grown in a low oxygen tension environment. Therefore, the oxygen tension environment seems to influence the efficacy of the tested agents.

  1. Sexuality, rights and personhood: tensions in a transnational world.

    Science.gov (United States)

    Siddiqi, Dina M

    2011-12-16

    This article discusses what happens when normative 'global' discourses of rights and individuated sexual identity confront the messiness of 'local' realities. It considers the tensions that emerge when the relationship between sexual and social identities is not obvious and the implications of such tensions for public health and sexual rights activism. These questions are addressed through debates over the naming of male-to-male sexualities and desires in the context of globalization and the growth of a large NGO (non-governmental organization) sector in urban Bangladesh. The material in the paper draws on a research project undertaken in 2008-9 in Dhaka, Bangladesh. A fundamental objective was to produce a contextualized understanding of sexuality in Dhaka city. Methods used included structured interviews, focus group discussions and informal conversations with a range of participants (students, factory workers, public health professionals and sexual minorities). The aim was to generate a conceptual and analytical framework around sexuality and rights rather than to undertake an empirical survey of any one population. As descriptors, globalized identity categories such as Men who have Sex with Men (MSM), used by public health providers, the state and donors; and gay/lesbian, invoked by human rights activists and transnational NGOs, are too narrow to capture the fluid and highly context-specific ways in which gender and sexually nonconforming persons understand themselves in Bangladesh. Further, class position mediates to a significant degree the reception, appropriation or rejection of transnational categories such as MSM and Lesbian, Gay, Bisexual, Transgender (LGBT). The tension is reflected in the sometimes fraught relations between service providers to MSM, the people they serve and an emerging group who identify as LGBT. A simple politics of recognition will be inadequate to the task of promoting health and human rights for all; such a strategy would

  2. Sexuality, rights and personhood: tensions in a transnational world

    Directory of Open Access Journals (Sweden)

    Siddiqi Dina M

    2011-12-01

    Full Text Available Abstract Background This article discusses what happens when normative ‘global’ discourses of rights and individuated sexual identity confront the messiness of ‘local’ realities. It considers the tensions that emerge when the relationship between sexual and social identities is not obvious and the implications of such tensions for public health and sexual rights activism. These questions are addressed through debates over the naming of male-to-male sexualities and desires in the context of globalization and the growth of a large NGO (non-governmental organization sector in urban Bangladesh. Methods The material in the paper draws on a research project undertaken in 2008-9 in Dhaka, Bangladesh. A fundamental objective was to produce a contextualized understanding of sexuality in Dhaka city. Methods used included structured interviews, focus group discussions and informal conversations with a range of participants (students, factory workers, public health professionals and sexual minorities. The aim was to generate a conceptual and analytical framework around sexuality and rights rather than to undertake an empirical survey of any one population. Results As descriptors, globalized identity categories such as Men who have Sex with Men (MSM, used by public health providers, the state and donors; and gay/lesbian, invoked by human rights activists and transnational NGOs, are too narrow to capture the fluid and highly context-specific ways in which gender and sexually nonconforming persons understand themselves in Bangladesh. Further, class position mediates to a significant degree the reception, appropriation or rejection of transnational categories such as MSM and Lesbian, Gay, Bisexual, Transgender (LGBT. The tension is reflected in the sometimes fraught relations between service providers to MSM, the people they serve and an emerging group who identify as LGBT. Conclusion A simple politics of recognition will be inadequate to the task of

  3. Growth factor involvement in tension-induced skeletal muscle growth

    Science.gov (United States)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  4. Oxygen Tension Regulates Human Mesenchymal Stem Cell Paracrine Functions.

    Science.gov (United States)

    Paquet, Joseph; Deschepper, Mickael; Moya, Adrien; Logeart-Avramoglou, Delphine; Boisson-Vidal, Catherine; Petite, Hervé

    2015-07-01

    : Mesenchymal stem cells (MSCs) have captured the attention and research endeavors of the scientific world because of their differentiation potential. However, there is accumulating evidence suggesting that the beneficial effects of MSCs are predominantly due to the multitude of bioactive mediators secreted by these cells. Because the paracrine potential of MSCs is closely related to their microenvironment, the present study investigated and characterized select aspects of the human MSC (hMSC) secretome and assessed its in vitro and in vivo bioactivity as a function of oxygen tension, specifically near anoxia (0.1% O2) and hypoxia (5% O2), conditions that reflect the environment to which MSCs are exposed during MSC-based therapies in vivo. In contrast to supernatant conditioned media (CM) obtained from hMSCs cultured at either 5% or 21% of O2, CM from hMSCs cultured under near anoxia exhibited significantly (p mesenchymal stem cell (hMSC) secretome and assessed its in vitro and in vivo biological bioactivity as a function of oxygen tension, specifically near anoxia (0.1% O2) and hypoxia (5% O2), conditions that reflect the environment to which MSCs are exposed during MSC-based therapies in vivo. The present study provided the first evidence of a shift of the hMSC cytokine signature induced by oxygen tension, particularly near anoxia (0.1% O2). Conditioned media obtained from hMSCs cultured under near anoxia exhibited significantly enhanced chemotactic and proangiogenic properties and a significant decrease in the inflammatory mediator content. These findings provide new evidence that elucidates aspects of great importance for the use of MSCs in regenerative medicine, could contribute to improving the efficacy of such therapies, and most importantly highlighted the interest in using conditioned media in therapeutic modalities. ©AlphaMed Press.

  5. Geometrical properties of tension-induced fractures in granite

    International Nuclear Information System (INIS)

    Sato, Hisashi; Sawada, Atsushi; Yasuhara, Hideaki

    2011-03-01

    Considering a safe, long-term sequestration of energy byproducts such as high level radioactive wastes, it is of significant importance to well-constrain the hydraulic and transport behavior of targeted permeants within fractured rocks. Specifically, fluid flow within low-permeability crystalline rock masses (e.g., granite) is often dominated by transport in through-cutting fractures, and thus careful considerations are needed on the behavior. There are three planes along that granites fail most easily under tension, and those may be identified as the rift, grain, and hardway planes. This anisotropic fabric may be attributed to preferentially oriented microcrack sets contained within intact rock. In this research, geometrical properties of tension-induced fractures are evaluated as listed below; (1) Creation of tension-induced fractures considering the anisotropy clarified by elastic wave measurements. (2) Evaluation of geometrical properties in those fractures characterized by the anisotropy. In the item (1), the three planes of rift, grain and hardway were identified by measuring elastic wave. In the item (2), JRC, variogram, fractal dimension and distributions of elevations in the fracture surfaces were evaluated using digitized data of the fracture surfaces measured via a laser profilometry. Results show that rift planes are less rougher than the other planes of grain and hardway, and grain planes are generically rougher than the other planes of rift and hardway. It was also confirmed that the fracture shape anisotropy was correlated with the direction of the slit which constructed during tensile tests. On the other hand, the tendency peculiar to the direction of slit and granites fail about the estimated aperture distribution from fracture shape was not seen. (author)

  6. Tension Pneumothorax and Subcutaneous Emphysema Complicating Insertion of Nasogastric Tube

    Directory of Open Access Journals (Sweden)

    Narjis AL Saif

    2015-01-01

    Full Text Available Nasogastric tube has a key role in the management of substantial number of hospitalized patients particularly the critically ill. In spite of the apparent simple insertion technique, nasogastric tube placement has its serious perhaps fatal complications which need to be carefully assessed. Pulmonary misplacement and associated complications are commonplace during nasogastric tube procedure. We present a case of tension pneumothorax and massive surgical emphysema in critically ill ventilated patient due to inadvertent nasogastric tube insertion and also discussed the risk factors, complication list, and arrays of techniques for safer tube placement.

  7. Wetting Transition and Line Tension of Oil on Water

    Science.gov (United States)

    Matsubara, H.; Aratono, M.

    Wetting has attracted wide attention in the field of applied chemistry because of its crucial importance in industrial operations such as coating, painting, and lubrication. Here, we summarize our fundamental understandings of surfactant-assisted wetting transitions which we have found and studied for the last ten years. The difference between the surfactant-assisted wetting transitions and existing ones is discussed. Moreover, the relation between wetting transitions and the stability of the three-phase contact line is examined in terms of the line tension of oil lenses.

  8. Acoustic emission monitoring of the bending under tension test

    DEFF Research Database (Denmark)

    Moghadam, Marcel; Sulaiman, Mohd Hafis Bin; Christiansen, Peter

    2017-01-01

    Preliminary investigations have shown that acoustic emission has promising aspects as an online monitoring technique for assessment of tribological conditions during metal forming as regards to determination of the onset of galling. In the present study the acoustic emission measuring technique h...... in BUT testing has been found to describe the frictional conditions during forming well and to allow for accurate assessment of the limits of lubrication....... been applied for online monitoring of the frictional conditions experienced during Bending Under Tension (BUT) testing. The BUT test emulates the forming conditions experienced when drawing sheet material over a die curvature as in deep drawing processes. Monitoring of the developed acoustic emission...

  9. Liquid-liquid interfacial tension of electrolyte solutions

    OpenAIRE

    Bier, Markus; Zwanikken, Jos; van Roij, Rene

    2008-01-01

    It is theoretically shown that the excess liquid-liquid interfacial tension between two electrolyte solutions as a function of the ionic strength I behaves asymptotically as O(- I^0.5) for small I and as O(+- I) for large I. The former regime is dominated by the electrostatic potential due to an unequal partitioning of ions between the two liquids whereas the latter regime is related to a finite interfacial thickness. The crossover between the two asymptotic regimes depends sensitively on mat...

  10. [Cultural diversity, tensions and solidarities within the nursing teams].

    Science.gov (United States)

    Kessar, Zahia; Kotobi, Laurence

    2018-05-01

    Cultural and ethnic diversities present in the hospital as well as within the nursing teams impact on the way of working. Observing them from the point of view of the caregivers based on experiences of team guidance and training highlights issues related to the way the hospital teams experience these differences. These differences also have an effect conveyed through tensions, conflicts or solidarity. The place and the role of the managers are an important lever for supporting their teams, notably with regard to racism which can sometimes be expressed in the social relations present in the workplace. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  11. Gravitino/axino as decaying dark matter and cosmological tensions

    Directory of Open Access Journals (Sweden)

    Koichi Hamaguchi

    2017-09-01

    Full Text Available In supersymmetric axion models, if the gravitino or axino is the lightest SUSY particle (LSP, the other is often the next-to-LSP (NLSP. We investigate the cosmology of such a scenario and point out that the lifetime of the NLSP naturally becomes comparable to the present age of the universe in a viable parameter region. This is a well-motivated example of the so-called decaying dark matter model, which is recently considered as an extension of the ΛCDM model to relax some cosmological tensions.

  12. Tension pneumoperitoneum after bystander cardiopulmonary resuscitation: A case report

    Directory of Open Access Journals (Sweden)

    Sherry Johnson

    2018-01-01

    Conclusion: The Veress needle, usually used for insufflating the abdomen during laparoscopy, can also be an effective tool to decompress the abdomen when presented with tension pneumoperitoneum. Abdominal visceral injuries are rare following CPR but do occur and will likely require an invasive intervention. Surviving cardiac arrest as a young person and living without deficits outweighs the risk of a surgical correction for a visceral injury. While resuscitation measures are critical for survival, medical personnel need to be aware of potential complications from resuscitative efforts and potential management strategies.

  13. Essential tension: specialization with broad and general training in psychology.

    Science.gov (United States)

    Roberts, Michael C

    2006-11-01

    The practice fields of psychology develop through specialization in training and education. The recognized specialties play a major role in developing new opportunities for professional psychology and providing quality services for the public. The essential tension comes from the balance of innovation and tradition and, in professional psychology, from the balance of fragmentation and unification. As an example, specialization in clinical child psychology is integrated within the broad and general traditions. The greater degree of focused science and practice in a specialty is the logical consequence of advances of the discipline and profession of psychology. ((c) 2006 APA, all rights reserved).

  14. Surface tension propulsion of fungal spores by use of microdroplets

    OpenAIRE

    Noblin, Xavier; Yang, Sylvia; Dumais, Jacques

    2010-01-01

    Many edible mushrooms eject their spores (about 10 microns in size) at high speed (about 1 m/s) using surface tension forces in a few microseconds. Basically the coalescence of a droplet with the spore generates the necessary momentum to eject the spore. We have detailed this mechanism in \\cite{noblin2}. In this article, we give some details about the high speed movies (up to 250000 fps) of mushrooms' spores ejection attached to this submission. This video was submitted as part of the Gallery...

  15. New daily-persistent headache versus tension-type headache.

    Science.gov (United States)

    Robbins, Matthew S; Crystal, Sara C

    2010-12-01

    New daily-persistent headache (NDPH) and chronic tension-type headache (CTTH) are two forms of primary chronic daily headache of long duration that often are similar in their headache manifestations. NDPH distinguishes itself from CTTH and the other forms of chronic daily headache by its continuous head pain from onset. However, despite formalized criteria that specify NDPH must resemble the acute onset of a headache identical to that of CTTH, NDPH commonly has migraine features. Here, we review the available literature on NDPH and compare its clinical features, epidemiology, prognosis, inciting factors, and treatment to CTTH.

  16. Surface tension, hydrophobicity, and black holes: The entropic connection

    International Nuclear Information System (INIS)

    Callaway, D.J.

    1996-01-01

    The geometric entropy arising from partitioning space in a fluid open-quote open-quote field theory close-quote close-quote is shown to be linearly proportional to the area of an excluded region. The coefficient of proportionality is related to surface tension by a thermodynamic argument. Good agreement with experimental data is obtained for a number of fluids. The calculation employs a density-matrix formalism developed previously for studying the origin of black hole entropy. This approach may lead to a practical technique for the evaluation of thermodynamic quantities with important entropic components. copyright 1996 The American Physical Society

  17. [Phacoemulsification of subluxated lens with capsular tension ring implantation].

    Science.gov (United States)

    Dorecka, Mariola; Rokicki, Wojciech; Nita, Malgorzata; Krysik, Katarzyna; Nita, Ewa; Sikorska, Aleksandra; Romaniuk, Wanda

    2007-01-01

    To evaluate long term results of phacoemulsification with PC IOL and capsular tension ring (CTR) implantation in lens subluxation. The study comprised of 134 patients--146 eyes with subluxated lens. In all cases phacoemulsification with PC IOL and CTR implantation was performed. No intaroperative complications has occured. Postoperative complications included: inflammation in the anterior chamber in 3 eyes (2.1%), retinal detachment in 2 eyes (1.4%). In all cases there was no PC IOL decentration. (1) CTR facilitates phacoemulsification with PC IOL implantation in lens subluxation. (2) Phacoemulsification of subluxated lens with PC IOL and CTR implantation seems to be safe and effective procedure.

  18. Length and elasticity of side reins affect rein tension at trot.

    Science.gov (United States)

    Clayton, Hilary M; Larson, Britt; Kaiser, LeeAnn J; Lavagnino, Michael

    2011-06-01

    This study investigated the horse's contribution to tension in the reins. The experimental hypotheses were that tension in side reins (1) increases biphasically in each trot stride, (2) changes inversely with rein length, and (3) changes with elasticity of the reins. Eight riding horses trotted in hand at consistent speed in a straight line wearing a bit and bridle and three types of side reins (inelastic, stiff elastic, compliant elastic) were evaluated in random order at long, neutral, and short lengths. Strain gauge transducers (240 Hz) measured minimal, maximal and mean rein tension, rate of loading and impulse. The effects of rein type and length were evaluated using ANOVA with Bonferroni post hoc tests. Rein tension oscillated in a regular pattern with a peak during each diagonal stance phase. Within each rein type, minimal, maximal and mean tensions were higher with shorter reins. At neutral or short lengths, minimal tension increased and maximal tension decreased with elasticity of the reins. Short, inelastic reins had the highest maximal tension and rate of loading. Since the tension variables respond differently to rein elasticity at different lengths, it is recommended that a set of variables representing different aspects of rein tension should be reported. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Evaluation of tension stiffening effect on the crack width calculation of flexural RC members

    Directory of Open Access Journals (Sweden)

    Said M. Allam

    2013-06-01

    Full Text Available Building codes consider the tension stiffening when calculating the crack width of the flexural members. A simple analytical procedure is proposed for the determination of forces, stresses and strains acting on a reinforced concrete section subjected to flexure considering the concrete contribution in tension up to tensile concrete strain corresponding to the cracking strength of concrete. This analytical method gives the minimum value (lower bound of tension stiffening. Also, a commercial Finite Element Program (ABAQUS 2007 was used to perform non-linear analysis in order to evaluate the total contribution of the tensioned concrete in carrying loads which may be considered as the upper bound of tension stiffening. In addition, a comparison is carried out among the different codes using four reinforced concrete rectangular models to compare and evaluate the tension stiffening with proposed analytical lower bound tension stiffening and upper bound as obtained by ABAQUS. The models include different percentages of flexural steel ratio. The comparison revealed that the codes’ equations always consider tension stiffening lying between lower and upper bound of tension stiffening proposed in this study. Also, the study showed that the tension stiffening decreases with the increase of the percentage of the flexural reinforcement ratio.

  20. Síndrome de bajo gasto cardíaco en la tetralogía de Fallot

    Directory of Open Access Journals (Sweden)

    Lincoln de la Parte Pérez

    2002-06-01

    Full Text Available Se realiza un estudio retrospectivo de 200 niños operados de tetralogía de Fallot en el Cardiocentro del Hospital Pediátrico Universitario "William Soler" durante el período comprendido entre los años 1990 y 1993. Se observó una relación directamente proporcional entre el tiempo de pinzamiento aórtico (paro anóxico, el tiempo de circulación extracorpórea (CEC y el desarrollo del síndrome de bajo gasto cardíaco. La incidencia de bajo gasto cardíaco en los niños con tiempo de pinzamiento aórtico menor a los 30 min fue nula, en los pacientes con tiempo menor a los 60 min la incidencia fue del 23,2 % (40 pacientes. En los 24 pacientes que sufrieron procedimientos quirúrgicos prolongados y tiempo de pinzamiento aórtico mayor de 1 hora la incidencia fue del 95,8 %. En los pacientes con tiempo de CEC menor de 90 min la incidencia de bajo gasto cardíaco que de sólo el 9,75 %, en los niños con tiempo de CEC entre 91 y 105 min fue de 15,53 %, en los que necesitaron entre 106 y 120 min de CEC fue del 62,5 % y en los procedimientos quirúrgicos prolongados fue del 95,8 %. La mayoría de los pacientes respondió bien al tratamiento, aunque en un pequeño número de ellos se mantuvo la disfunción ventricular a pesar del tratamiento. Siete niños fallecieron en el posoperatorio para una mortalidad del 3,5 %.A retrospective study of 200 children with Tetralogy of Fallot, who were operated on the Cardiology Center of "William Soler" University Pediatric Hospital from 1990 to 1993, was performed. There was a direct proportional relation between time of holding aorta with forceps (anoxic arrest, time of extracorporeal circulation and the development of low cardiac output syndrome. The incidence of low cardiac output in children who underwent holding of aorta with forceps for less than 30 minutes was zero, but the same procedure applied in patients for less than 60 minutes, the incidence was 23,2%(40 patients. The 24 patients that underwent

  1. Effect of pneumatic tourniquet on muscle oxygen tension.

    Science.gov (United States)

    Santavirta, S; Höckerstedt, K; Niinikoski, J

    1978-10-01

    Recent investigations suggest that circulation in a limb can be reduced with a tourniquet to less than 1 per cent of the control limb, or even completely occluded. The development of tissue oxygen tonometry with implanted silastic tubes has provided new possibilities for assessing muscle tissue oxygen tension. In the present work, this method was employed to register the effect of tourniquet blackade on the lower limb muscle PO2 in rabbits. The duration of the tourniquet blockade was 60, 120 and 180 minutes. The baseline muscle PO2 in the tibialis anterior muscle was 22.6 +/- 0.6 mmHg. During the tourniquet blockade the oxygen tension dropped to minimal values between 9.2 +/- 0.5 and 10.7 +/- 0.6 mmHg in these experimental groups, but the tissue microclimate never reached fully anoxic conditions. The rapid response of muscle PO2 to oxygen breathing after release of the blockade suggests that limb microcirculation tolerates tourniquet occlusion well.

  2. Strain rate effects on reinforcing steels in tension

    Science.gov (United States)

    Cadoni, Ezio; Forni, Daniele

    2015-09-01

    It is unquestionable the fact that a structural system should be able to fulfil the function for which it was created, without being damaged to an extent disproportionate to the cause of damage. In addition, it is an undeniable fact that in reinforced concrete structures under severe dynamic loadings, both concrete and reinforcing bars are subjected to high strain-rates. Although the behavior of the reinforcing steel under high strain rates is of capital importance in the structural assessment under the abovementioned conditions, only the behaviour of concrete has been widely studied. Due to this lack of data on the reinforcing steel under high strain rates, an experimental program on rebar reinforcing steels under high strain rates in tension is running at the DynaMat Laboratory. In this paper a comparison of the behaviour in a wide range of strain-rates of several types of reinforcing steel in tension is presented. Three reinforcing steels, commonly proposed by the European Standards, are compared: B500A, B500B and B500C. Lastly, an evaluation of the most common constitutive laws is performed.

  3. Liquid metal actuator driven by electrochemical manipulation of surface tension

    Science.gov (United States)

    Russell, Loren; Wissman, James; Majidi, Carmel

    2017-12-01

    We examine the electrocapillary properties of a fluidic actuator composed of a liquid metal droplet that is submerged in electrolytic solution and attached to an elastic beam. The beam deflection is controlled by electrochemically driven changes in the surface energy of the droplet. The metal is a eutectic gallium-indium alloy that is liquid at room temperature and forms an nm-thin Ga2O3 skin when oxidized. The effective surface tension of the droplet changes dramatically with oxidation and reduction, which are reversibly controlled by applying low voltage to the electrolytic bath. Wetting the droplet to two copper pads allows for a controllable tensile force to be developed between the opposing surfaces. We demonstrate the ability to reliably control force by changing the applied oxidizing voltage. Actuator forces and droplet geometries are also examined by performing a computational fluid mechanics simulation using Surface Evolver. The theoretical predictions are in qualitative agreement with the experimental measurements and provide additional confirmation that actuation is driven by surface tension.

  4. Creep rupture of mild steel compact tension test pieces

    International Nuclear Information System (INIS)

    Priddle, E.K.

    1978-10-01

    Creep rupture lives have been determined for compact tension and unnotched tensile test pieces of mild steel at 450 0 C. Three sizes of compact tension specimens were used in which the ratios of reference stress to elastic stress intensity factor were 2.76, 4.78 and 6.6 (msup(-1/2)). The analysis of results in terms of either initial reference stress or stress intensity was unable to reduce the data to a single failure curve. An empirical correlation was found between rupture time and a reference stress/crack length combination where t = 2.46 x 10 20 sub(σref) sup(-8.96) asup(-1.56) (units hours, MPa and metres). This equation has no valid application to materials or specimens other than those from which it was derived. Reported data for 1/2Cr Mo V and 2 1/4Cr Mo steels at 565 0 C were also correlated by this approach. (author)

  5. School and community relations in North America: Creative tensions

    Science.gov (United States)

    Loughran, E.; Reed, H. B.

    1980-09-01

    School and community relations in North America reflect creative tensions between the conserving forces of schooling and the changing forces of community. During crisis periods community development needs may modify the school's focus on individual learner growth, but generally schools use the community to extend and enrich the traditional modes. School and community interactions are chiefly characterized by such settings as community schools, community education, adult education, home and school (PTA) associations, work-study programs, curriculum-community resource programs. Recent social forces are creating heightened tensions: cultural pluralism, reduced resources, Third World influences, international conflicts, personal alienation, population concerns, energy problems, community power issues. These forces are gradually shifting school and community concepts towards ones of education and community. Education goes well beyond schooling, including all agencies having an organized influence on community development: libraries, voluntary groups, unions, business, human service agencies, government units, as well as schools. This shift requires research to develop nonformal concepts and practices, along with formal pedagogy, to increase the positive impacts of educational networks on community, as well as individual, development. These new directions have not yet significantly modified the traditional meaning of school and community relations.

  6. Takotsubo Cardiomyopathy in the Setting of Tension Pneumothorax.

    Science.gov (United States)

    Gale, Michael; Loarte, Pablo; Mirrer, Brooks; Mallet, Thierry; Salciccioli, Louis; Petrie, Alison; Cohen, Ronny

    2015-01-01

    Background. Takotsubo cardiomyopathy is defined as a transient left ventricular dysfunction, usually accompanied by electrocardiographic changes. The literature documents only two other cases of Takotsubo cardiomyopathy in the latter setting. Methods. A 78-year-old female presented to the ED with severe shortness of breath, hypertension, and tachycardia. On physical exam, heart sounds (S1 and S2) were regular and wheezing was noticed bilaterally. We found laboratory results with a WBC of 20.0 (103/μL), troponin of 16.52 ng/mL, CK-mb of 70.6%, and BNP of 177 pg/mL. The patient was intubated for acute hypoxemic respiratory failure. A chest X-ray revealed a large left-sided tension pneumothorax. Initial echocardiogram showed apical ballooning with a LVEF of 10-15%. A cardiac angiography revealed normal coronary arteries with no coronary disease. After supportive treatment, the patient's condition improved with a subsequent echocardiogram showing a LVEF of 60%. Conclusion. The patient was found to have Takotsubo cardiomyopathy in the setting of a tension pneumothorax. The exact mechanisms of ventricular dysfunction have not been clarified. However, multivessel coronary spasm or catecholamine cardiotoxicity has been suggested to have a causative role. We suggest that, in our patient, left ventricular dysfunction was induced by the latter mechanism related to the stress associated with acute pneumothorax.

  7. Takotsubo Cardiomyopathy in the Setting of Tension Pneumothorax

    Directory of Open Access Journals (Sweden)

    Michael Gale

    2015-01-01

    Full Text Available Background. Takotsubo cardiomyopathy is defined as a transient left ventricular dysfunction, usually accompanied by electrocardiographic changes. The literature documents only two other cases of Takotsubo cardiomyopathy in the latter setting. Methods. A 78-year-old female presented to the ED with severe shortness of breath, hypertension, and tachycardia. On physical exam, heart sounds (S1 and S2 were regular and wheezing was noticed bilaterally. We found laboratory results with a WBC of 20.0 (103/μL, troponin of 16.52 ng/mL, CK-mb of 70.6%, and BNP of 177 pg/mL. The patient was intubated for acute hypoxemic respiratory failure. A chest X-ray revealed a large left-sided tension pneumothorax. Initial echocardiogram showed apical ballooning with a LVEF of 10–15%. A cardiac angiography revealed normal coronary arteries with no coronary disease. After supportive treatment, the patient’s condition improved with a subsequent echocardiogram showing a LVEF of 60%. Conclusion. The patient was found to have Takotsubo cardiomyopathy in the setting of a tension pneumothorax. The exact mechanisms of ventricular dysfunction have not been clarified. However, multivessel coronary spasm or catecholamine cardiotoxicity has been suggested to have a causative role. We suggest that, in our patient, left ventricular dysfunction was induced by the latter mechanism related to the stress associated with acute pneumothorax.

  8. Pain perception studies in tension-type headache.

    Science.gov (United States)

    Bezov, David; Ashina, Sait; Jensen, Rigmor; Bendtsen, Lars

    2011-02-01

    Tension-type headache (TTH) is a disorder with high prevalence and significant impact on society. Understanding of pathophysiology of TTH is paramount for development of effective treatments and prevention of chronification of TTH. Our aim was to review the findings from pain perception studies of pathophysiology of TTH as well as to review the research of pathophysiology of TTH. Pain perception studies such as measurement of muscle tenderness, pain detection thresholds, pain tolerance thresholds, pain response to suprathreshold stimulation, temporal summation and diffuse noxious inhibitory control (DNIC) have played a central role in elucidating the pathophysiology of TTH. It has been demonstrated that continuous nociceptive input from peripheral myofascial structures may induce central sensitization and thereby chronification of the headache. Measurements of pain tolerance thresholds and suprathreshold stimulation have shown presence of generalized hyperalgesia in chronic tension-type headache (CTTH) patients, while DNIC function has been shown to be reduced in CTTH. One imaging study showed loss of gray matter structures involved in pain processing in CTTH patients. Future studies should aim to integrate pain perception and imaging to confirm this finding. Pharmacological studies have shown that drugs like tricyclic anti-depressant amitriptyline and nitric oxide synthase inhibitors can reverse central sensitization and the chronicity of headache. Finally, low frequency electrical stimulation has been shown to rapidly reverse central sensitization and may be a new modality in treatment of CTTH and other chronic pain disorders. © 2010 American Headache Society.

  9. Effect of rajyoga meditation on chronic tension headache.

    Science.gov (United States)

    Kiran; Girgla, Kawalinder K; Chalana, Harsh; Singh, Harjot

    2014-01-01

    Chronic tension-type headache (CTTH) is the most common type of headache with no truly effective treatment. This study was designed to correlate the additive effect of meditation on CTTH patients receiving medical treatment. 50 patients (aged 18-58 years) presenting with a clinical diagnosis of CCTH, were divided in 2 groups. Group 1 (n=30) received 8 lessons and practical demonstration of Brahmakumaris spiritual based meditation known as Rajyoga meditation for relaxation therapy, in addition to routine medical treatment (analgesics and muscle relaxants). Group 2 (n=20) patients received analgesics and muscle relaxants twice a day but no relaxation therapy in the form of meditation. Both groups were followed up for 8 weeks period. The parameters studied were severity, frequency and duration of CCTH, and their headache index calculated. Patients in both groups showed a highly significant reduction in headache variables (Pheadache, duration & frequency in Group 1 was 94%, 91% and 97% respectively whereas in Group 2 it was 36%, 36% and 49% respectively. Headache relief as calculated by headache index was 99% in Group 1 as compared to 51% in Group 2. Even Short term spiritual based relaxation therapy (Rajyoga meditation) was highly effective in causing earlier relief in chronic tension headache as measured by headache parameter.

  10. Tension pneumocephalus mimicking septic shock: a case report.

    Science.gov (United States)

    Miranda, Caroline; Mahta, Ali; Wheeler, Lee Adam; Tsiouris, A John; Kamel, Hooman

    2018-02-01

    Tension pneumocephalus can lead to rapid neurologic deterioration. We report for the first time its association with aseptic systemic inflammatory response syndrome mimicking septic shock and the efficacy of prompt neurosurgical intervention and critical care support in treating this condition. A 64-year-old man underwent 2-stage olfactory groove meningioma resection. The patient developed altered mental status and gait instability on postoperative day 6. Imaging showed significant pneumocephalus. The patient subsequently developed worsening mental status, respiratory failure, and profound shock requiring multiple vasopressors. Bedside needle decompression, identification and repair of the cranial fossa defect, and critical care support led to improved mental status and reversal of shock and multiorgan dysfunction. Thorough evaluation revealed no evidence of an underlying infection. In this case, tension pneumocephalus incited an aseptic systemic inflammatory response syndrome mimicking septic shock. Prompt neurosurgical correction of pneumocephalus and critical care support not only improved neurologic status, but also reversed shock. Such a complication indicates the importance of close monitoring of patients with progressive pneumocephalus.

  11. Tension pneumocephalus mimicking septic shock: a case report

    Directory of Open Access Journals (Sweden)

    Caroline Miranda, MD

    2018-02-01

    Full Text Available Tension pneumocephalus can lead to rapid neurologic deterioration. We report for the first time its association with aseptic systemic inflammatory response syndrome mimicking septic shock and the efficacy of prompt neurosurgical intervention and critical care support in treating this condition. A 64-year-old man underwent 2-stage olfactory groove meningioma resection. The patient developed altered mental status and gait instability on postoperative day 6. Imaging showed significant pneumocephalus. The patient subsequently developed worsening mental status, respiratory failure, and profound shock requiring multiple vasopressors. Bedside needle decompression, identification and repair of the cranial fossa defect, and critical care support led to improved mental status and reversal of shock and multiorgan dysfunction. Thorough evaluation revealed no evidence of an underlying infection. In this case, tension pneumocephalus incited an aseptic systemic inflammatory response syndrome mimicking septic shock. Prompt neurosurgical correction of pneumocephalus and critical care support not only improved neurologic status, but also reversed shock. Such a complication indicates the importance of close monitoring of patients with progressive pneumocephalus.

  12. Combined tension and bending testing of tapered composite laminates

    Science.gov (United States)

    O'Brien, T. Kevin; Murri, Gretchen B.; Hagemeier, Rick; Rogers, Charles

    1994-11-01

    A simple beam element used at Bell Helicopter was incorporated in the Computational Mechanics Testbed (COMET) finite element code at the Langley Research Center (LaRC) to analyze the responce of tappered laminates typical of flexbeams in composite rotor hubs. This beam element incorporated the influence of membrane loads on the flexural response of the tapered laminate configurations modeled and tested in a combined axial tension and bending (ATB) hydraulic load frame designed and built at LaRC. The moments generated from the finite element model were used in a tapered laminated plate theory analysis to estimate axial stresses on the surface of the tapered laminates due to combined bending and tension loads. Surfaces strains were calculated and compared to surface strains measured using strain gages mounted along the laminate length. The strain distributions correlated reasonably well with the analysis. The analysis was then used to examine the surface strain distribution in a non-linear tapered laminate where a similarly good correlation was obtained. Results indicate that simple finite element beam models may be used to identify tapered laminate configurations best suited for simulating the response of a composite flexbeam in a full scale rotor hub.

  13. Choroidal Excavation in Eye with Normal Tension Glaucoma

    Directory of Open Access Journals (Sweden)

    Kazunobu Asao

    2014-05-01

    Full Text Available Purpose: To report the case of an eye with normal tension glaucoma and a choroidal excavation. Methods: This is an observational case report. Results: A 59-year-old woman with normal tension glaucoma had a choroidal excavation in the left eye. Her best-corrected visual acuity and intraocular pressure were within normal limits and had been stable for 5 years. Fundus examination showed a small white lesion inferior to the macula and a nerve fiber layer defect at the inferior edge of the optic disc. Humphrey Field Analyzer (HFA showed visual field defects corresponding to the nerve fiber layer defect with C30-2, and a central scotoma superior to the macula with C10-2. Optical coherence tomography (OCT showed a 150-µm deep choroidal excavation. Disruptions of the IS/OS line were detected only in the area inferior to the choroidal excavation. During the 5 months of follow-up, her best-corrected visual acuity remained at 1.0 and the IOP ranged from 12 to 14 mm Hg in the left eye. The fundus and OCT images did not deteriorate and the choroidal excavation did not enlarge. Conclusions: The disruption of the inner/outer segment (IS/OS line was detected only at the area surrounding the choroidal excavation. OCT examinations are useful in assessing the area of the residual IS/OS line, and HFA can be used to estimate the residual central visual field.

  14. Particularizing spirituality in points of tension: enriching the discourse.

    Science.gov (United States)

    Pesut, Barbara; Fowler, Marsha; Reimer-Kirkham, Sheryl; Taylor, Elizabeth Johnston; Sawatzky, Rick

    2009-12-01

    The tremendous growth in nursing literature about spirituality has garnered proportionately little critique. Part of the reason may be that the broad generalizing claims typical of this literature have not been sufficiently explicated so that their particular implications for a practice discipline could be evaluated. Further, conceptualizations that attempt to encompass all possible views are difficult to challenge outside of a particular location. However, once one assumes a particular location in relation to spirituality, then the question becomes how one resolves the tension between what are essentially theological or philosophical commitments and professional commitments. In this study, we discuss the tension between these perspectives using the idea of a responsible nursing response to spiritual pluralism. We then problematize three claims about spirituality in nursing discourse based upon our location as scholars influenced by Christian theological understandings: (i) the claim that all individuals are spiritual; (ii) the claim that human spirituality can be assessed and evaluated; and (iii) the claim that spirituality is a proper domain of nursing's concern and intervention. We conclude by suggesting that the widely shared values of social justice, compassion and human dignity may well serve as a grounding for the critique of spiritual discourses in nursing across particularized positions.

  15. Dynamic Bubble Surface Tension Measurements in Northwest Atlantic Seawater

    Science.gov (United States)

    Kieber, D. J.; Long, M. S.; Keene, W. C.; Kinsey, J. D.; Frossard, A. A.; Beaupre, S. R.; Duplessis, P.; Maben, J. R.; Lu, X.; Chang, R.; Zhu, Y.; Bisgrove, J.

    2017-12-01

    Numerous reports suggest that most organic matter (OM) associated with newly formed primary marine aerosol (PMA) originates from the sea-surface microlayer. However, surface-active OM rapidly adsorbs onto bubble surfaces in the water column and is ejected into the atmosphere when bubbles burst at the air-water interface. Here we present dynamic surface tension measurements of bubbles produced in near surface seawater from biologically productive and oligotrophic sites and in deep seawater collected from 2500 m in the northwest Atlantic. In all cases, the surface tension of bubble surfaces decreased within seconds after the bubbles were exposed to seawater. These observations demonstrate that bubble surfaces are rapidly saturated by surfactant material scavenged from seawater. Spatial and diel variability in bubble surface evolution indicate corresponding variability in surfactant concentrations and/or composition. Our results reveal that surface-active OM is found throughout the water column, and that at least some surfactants are not of recent biological origin. Our results also support the hypothesis that the surface microlayer is a minor to negligible source of OM associated with freshly produced PMA.

  16. La corriente en chorro de bajo nivel sobre los Llanos Venezolanos de Sur América

    Directory of Open Access Journals (Sweden)

    Eddison R. Torrealba

    2010-01-01

    Full Text Available Utilizando observaciones del PACS-SONET (2001-2006, de radiosondeo (2007, de estaciones meteorológicas de superficie y datos del NCEP-NCAR, se analiza y documenta la estructura y variabilidad espacio-temporal de la corriente en chorro de bajo nivel en los Llanos de Venezuela al norte de Sur América. Esta corriente, relativamente menos estudiada que otras en la región, muestra valores medios de 11 m/s durante el verano austral (noviembre-abril en 925 hPa (750 m.s.n.m., aproximadamente y con valores de la cortante vertical del viento cercanos a 1 m/s por cada 100 m en el primer km, aproximadamente, con máximos absolutos mayores de 14 m/s en febrero. Arriba de 925 hPa, la corriente disminuye rápidamente a 6 m/s cerca de 700 hPa. Se observa un marcado ciclo diurno, con máximos a las 12:00 UTC y vientos relativamente débiles alrededor de las 21:00 UTC, manifestando fuertes cambios en la cortante vertical del viento en enero-marzo del periodo analizado. La variabilidad intraestacional de la corriente es muy fuerte con periodos hasta de varios días, en los cuales, los vientos asociados a esta corriente son muy débiles. En pocos días, los vientos pueden variar de 25 m/s a valores cercanos a los 5 m/s. Los mecanismos físicos responsables de estos cambios no son evidentes, sin embargo, los mismos muestran una importante relación con los observados en la temperatura cerca de superficie. En algunas estaciones analizadas, la cortante vertical del viento presenta máximos valores durante la época seca y mínimos para la lluviosa, indicando la importancia física de este índice para el desarrollo de la convección. La corriente de bajo nivel también muestra una marcada variabilidad interanual. Respecto a su extensión zonal y meridional, los datos analizados sugieren valores de 1500 km y 500 km, respectivamente.

  17. Desarrollo radical y rendimiento en diferentes variedades de trigo, cebada y triticale bajo condiciones limitantes de humedad del suelo

    Directory of Open Access Journals (Sweden)

    Luis Eduardo Miranda Domínguez

    2016-10-01

    Full Text Available El trigo (Triticum aestivum L., triticale (Triticosecale Wittmack y cebada (Hordeum vulgare L., se cultivan en México bajo riego y temporal o secano. En condiciones de secano se cultivan en la temporada de lluvias en verano-otoño y otoño-invierno con humedad residual, después de la temporada de lluvias, aunque con severos problemas de sequía terminal. El presente trabajo tuvo como objetivo estudiar el rendimiento de grano (RG y sus componentes, y la densidad radical (DR bajo condiciones de humedad residual en Oaxaca, México, durante el periodo otoño-invierno 2013-2014. Se utilizó un diseño experimental de bloques completos al azar con cuatro repeticiones; la unidad experimental fue de cuatro surcos de 4 ×0.4 m. Se sembró el 5 de octubre de 2013 con una densidad de siembra de 100 kg ha-1 y se fertilizó con la dosis 40-40-00. La cebada produjo mayor RG que el trigo y el triticale; el alto RG estuvo acompañado de un alto índice de cosecha (IC, peso del grano (PG y DR, y menor estatura de planta y ciclo biológico (CB más corto. El trigo y el triticale tuvieron un RG similar, sin embargo, el trigo ‘Venturero’ tuvo mayor RG que la mayoría de los genotipos de trigo y triticale con alto número de espigas m-2 (E M-2 y PG, y el más alto peso hectolitrico, la mayor DR y el CB más largo. Más del 50% de las raíces se concentraron cerca de la superficie del suelo (20 cm en todos los genotipos y se observó que el trigo tuvo mayor DR que la cebada y el triticale en los estratos de 20-100 cm, y el trigo ‘Venturero’ produjo más raíces que los demás genotipos desde la superficie del suelo hasta los 100 cm. Los genotipos de cebada y trigo con mayor DR produjeron mayor RG, confirmando su mayor resistencia a sequía.

  18. Rein tension acceptance in young horses in a voluntary test situation

    DEFF Research Database (Denmark)

    Christensen, Janne Winther; zharkikh, T.L.; Antoine, A.

    2011-01-01

    Reasons for performing the study: During riding, horses are frequently exposed to pressure from the rider, e.g. through the bit and reins, but few studies have investigated at which point rein tension becomes uncomfortable for the horse. Objectives: To investigate how much rein tension young...... inexperienced horses are willing to accept in order to obtain a food reward; whether the tension acceptance changes during 3 consecutive test days; and whether rein tension correlates with the expression of conflict behaviour and heart rate. Hypotheses: Pressure-naïve horses will apply only little rein tension...... in the first voluntary trial, but their acceptance will gradually increase. High levels of rein tension will lead to expression of conflict behaviour and increases in heart rate. Methods: Fifteen 2-year-old, bridle-naïve mares were encouraged to stretch their head forward (across a 0.95 m high metal bar...

  19. A wireless smart sensor network for automated monitoring of cable tension

    International Nuclear Information System (INIS)

    Sim, Sung-Han; Cho, Soojin; Li, Jian; Jo, Hongki; Park, Jong-Woong; Jung, Hyung-Jo; Spencer Jr, Billie F

    2014-01-01

    As cables are primary load carrying members in cable-stayed bridges, monitoring the tension forces of the cables provides valuable information regarding structural soundness. Incorporating wireless smart sensors with vibration-based tension estimation methods provides an efficient means of autonomous long-term monitoring of cable tensions. This study develops a wireless cable tension monitoring system using MEMSIC’s Imote2 smart sensors. The monitoring system features autonomous operation, sustainable energy harvesting and power consumption, and remote access using the internet. To obtain the tension force, an in-network data processing strategy associated with the vibration-based tension estimation method is implemented on the Imote2-based sensor network, significantly reducing the wireless data transmission and the power consumption. The proposed monitoring system has been deployed and validated on the Jindo Bridge, a cable-stayed bridge located in South Korea. (paper)

  20. Measurement of calcium influx in tethered rings of rabbit aorta under tension

    International Nuclear Information System (INIS)

    Gleason, M.M.; Ratz, P.H.; Flaim, S.F.

    1985-01-01

    Calcium (Ca) influx in vascular smooth muscle is routinely measured in untethered preparations not under passive stretch, and Ca influx data are correlated with data for steady-state isometric tension obtained under parallel conditions from tethered preparations under passive stretch. The validity of this method was tested by simultaneous measurement of Ca influx and tension in tethered rings of rabbit thoracic aorta. Ca influx ( 45 Ca 3-min pulse) and tension were measured at 3 and 30 min after norepinephrine (NE) or KCl and under control (no agonist) conditions. Active tension was significantly altered by variations in passive tension. Ca influx was unaffected by passive tension under control, NE, or KCl conditions, and results were similar at 3 and 30 min. The results confirm the validity of correlating Ca influx data from untethered rings with steady-state contractile response data obtained from tethered rings under similar experimental conditions