156 research outputs found

    Modelling of laser ablation and reactive oxygen plasmas for pulsed laser deposition of zinc oxide

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    Pulsed laser deposition (PLD) in a low-pressure oxygen atmosphere is commonly used for the production of high-quality, stoichiometric zinc oxide thin films. An alternative approach that has the potential benefit of increased process control is plasma-enhanced PLD, i.e. the use of a low-temperature oxygen plasma instead of a neutral gas. So far, the development of PE-PLD, and PLD in general, has been hampered by a lack of detailed understanding of the underpinning physics and chemistry. In this paper, we present modelling investigations aimed at further developing such understanding. Two-dimensional modelling of an inductively-coupled radio-frequency oxygen plasma showed that densities of 1014–1015 cm− 3 of reactive oxygen species O and O2* can be produced for operating pressures between 3 and 100 Pa. Together with the absolute densities of species, also the ratio between different reactive species, e.g. O and O2*, can be controlled by changing the operating pressure. Both can be used to find the optimum conditions for stoichiometric zinc oxide thin film deposition. Additionally, we investigated laser ablation of zinc using a different two-dimensional hydrodynamic code (POLLUX). This showed that the amount of material that is ablated increases from 2.9 to 4.7 μg per pulse for laser fluences from 2 to 10 J/cm2. However, the increased laser fluence also results in an increased average ionisation of the plasma plume, from 3.4 to 5.6 over the same fluence range, which is likely to influence the chemistry near the deposition substrate and consequently the film quality

    Investigations on Electrochemical Micro Drilling of Nickel Alloy using Taguchi based Grey Approach

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    Inconel 600 is the nickel based super alloy which is employed in numerous engineering applications like gas turbine blades, turbochargers and heat exchangers etc. However, it is very difficult to machine due to its high strength and poor thermal diffusion. Conventional machining methods of these materials may result in decreased life time. An electrochemical machining is an advanced non-traditional technique which is suitable for machining hard material, strenuous materials and Intricate shapes. In this paper, electrochemical micro drilling (ECMD) on Inconel 600 material is investigated. The experiments are devised and analyzed using Taguchi’s L18 orthogonal array and Grey relational analysis (GRA). Analysis of variance (ANOVA) has been implemented to find out the significance of electrochemical micro drilling parameters on the performance characteristics

    Investigations on Electrochemical Micro Drilling of Nickel Alloy using Taguchi based Grey Approach

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    424-429Inconel 600 is the nickel based super alloy which is employed in numerous engineering applications like gas turbine blades, turbochargers and heat exchangers etc. However, it is very difficult to machine due to its high strength and poor thermal diffusion. Conventional machining methods of these materials may result in decreased life time. An electrochemical machining is an advanced non-traditional technique which is suitable for machining hard material, strenuous materials and Intricate shapes. In this paper, electrochemical micro drilling (ECMD) on Inconel 600 material is investigated. The experiments are devised and analyzed using Taguchi’s L18 orthogonal array and Grey relational analysis (GRA). Analysis of variance (ANOVA) has been implemented to find out the significance of electrochemical micro drilling parameters on the performance characteristics

    Analysis of plasma enhanced pulsed laser deposition of transition metal oxide thin films using medium energy ion scattering

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    In this study, plasma-enhanced pulsed laser deposition (PE-PLD), which is a novel variant of pulsed laser deposition that combines laser ablation of metal targets with an electrically-produced oxygen plasma background, has been used for the fabrication of ZnO and Cu2O thin films. Samples prepared using the PE-PLD process, with the aim of generating desirable properties for a range of electrical and optical applications, have been analysed using medium energy ion scattering. Using a 100 keV He+ ion beam, high resolution depth profiling of the films was performed with an analysis of the stoichiometry and interface abruptness of these novel materials. It was found that the PE-PLD process can create stoichiometric thin films, the uniformity of which can be controlled by varying the power of the inductively coupled plasma. This technique showed a high deposition rate of ∼0.1 nm s−1

    Abordaxe fisioterápico no asma infantil

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    [Resumen] Objetivo: analizar qué intervenciones se están llevando a cabo por parte de la fisioterapia en la patología del asma. Material y métodos: revisión de artículos en los cuales se lleven a cabo intervenciones de fisioterapia en niños asmáticos. La búsqueda se efectuó en las bases de datos Pubmed, PEDro, Web of Science y Scopus, seleccionando artículos publicados entre 2013 y 2017 en lengua inglesa, portuguesa y española. Resultados: se seleccionaron 6 artículos, la mayoría de calidad intermedia, con variabilidad en el número de sujetos en cada estudio. La población que se seleccionó comprende desde el nacimiento hasta los 18 años. Las terapias fisioterápicas empleadas son variables. Se realiza en todos los casos un tratamiento enfocado al abordaje de las capacidades físicas por medio de diferentes programas de entrenamiento que cada estudio enfocó de forma diferente. Los aspectos más evaluados han sido la función pulmonar, la calidad de vida y la disnea, medidos a través de diferentes test y pruebas funcionales. Se obtienen resultados positivos en el manejo del asma con cada uno de estos programas de entrenamiento físico. Conclusiones: existen múltiples programas de intervención fisioterápica sobre el asma. Se llevan a cabo programas de entrenamiento de la musculatura inspiratoria, entrenamiento aeróbico, anaeróbico, de fuerza y equilibrio por parte de la fisioterapia en el abordaje de esta patología y todos presentan beneficio sobre ella. Asimismo, se objetivó que el programa de tratamiento que engloba un entrenamiento basado en ejercicio aeróbico y ejercicios respiratorios presenta una mayor eficacia.[Abstract] Objective: to analyze what interventions are being carried out by physiotherapy in the pathology of asthma. Material and methods: review of articles in which physiotherapy interventions are carried out in asthmatic children. The search was carried out in the Pubmed, PEDro, Web of Science and Scopus databases, selecting articles published between 2013 and 2017 in English, Portuguese and Spanish. Results: Six articles were selected, most of intermediate quality, with variability in the number of subjects in each study. The population that was selected comprises from birth to 18 years. The physiotherapeutic therapies used are variable. In all cases, a treatment focused on addressing physical abilities is carried out through different training programs that each study focused on differently. The most evaluated aspects have been pulmonary function, quality of life and dyspnea, measured through different tests and functional tests. Positive results are obtained in the management of asthma with each of these physical training programs. Conclusions: There are multiple programs of physiotherapy intervention on asthma. Training programs for inspiratory musculature, aerobic, anaerobic, strength and balance training are carried out by physiotherapy in the approach to this pathology and all have benefit over it. Likewise, it was found that the treatment program that includes a training based on aerobic exercise and breathing exercises is more effective.[Resumo] Obxectivo: analizar que intervencións se están a facer por parte da fisioterapia na patoloxía da asma. Material e metodoloxía: revisión de artículos nos que se fagan intervencións de fisioterapia en nenos asmáticos. A búsqueda efectuouse nas bases de datos Pubmed, PEDro, Web of Science y Scopus, seleccionando artículos publicados entre 2013 y 2017 en lingua inglesa, portuguesa e española. Resultados: seleccionáronse 6 artigos, a maioría de calidade intermedia, con variabilidade no número de suxeitos en cada estudo. A poboación que se seleccionou comprende dende o nacemento ata os 18 anos. As terapias fisioterápicas empregadas son variables. Realizouse en todos os casos un tratamento enfocado á abordaxe das capacidades físicas por medio de diferentes programas de entrenamento que cada estudo enfocou de forma diferente. Os aspectos máis avaliados foron a función pulmonar, a calidade da vida e a disnea, medidos a través de diferentes test e probas funcionais. Obtéñense resultados positivos no manexo do asma con cada un destes programas de entrenamento físico. Conclusións: existen múltiples programas de intervención fisioterápica sobre a asma infantil. Lévanse a cabo programas de entrenamento da musculatura inspiratoria, entrenamiento aeróbico, anaeróbico, de forza e equilibrio por parte da fisioterapia no abordaxe desta patoloxía e todos presentan beneficio sobre ela. Así mesmo obxectivouse que o programa de tratamento que engloba un entrenamento baseado no exercicio aeróbico e exercicios respiratorios presenta unha maior eficacia.Traballo fin de grao (UDC.FCS). Fisioterapia. Curso 2017/201

    Relationship between dichromate oxidizable and total soil organic carbon and distribution of different pools of organic carbon in Vertisols of Central India

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    Geo-referenced soil samples (0-15 cm) were collected from the farmers fields of Sehore (n = 120) and Vidisha (n = 156) district representing AESR 10.1 to establish the relationship between oxidizable SOC and total SOC in Vertisols of Central India and also to study the distribution of different pools of SOC as well as their relationship with crop yield. Total SOC was apportioned into different pools by using 5, 10 and 20 ml of concentrated H2SO4 that resulted in 3 acid-aqueous solution ratio of 0.5:1, 1:1 and 2:1. Also crop yields during the following winter season and rainy season from the geo-reference fields were recorded and were transformed to % relative yield. Oxidizable SOC (y) was related to total SOC (x) in the form of y = 0.825x – 0.086 (R2 = 0.958, n = 276), indicating that oxidizable SOC comprised 82.5% of the total SOC. Therefore it was recommended that a correction factor of 1.21 should be used to convert oxidizable SOC values to get the estimate of total SOC. The mean crop productivity was better related to oxidizable SOC (r = 0.5275) as compared to total SOC(r = 0.4886). The threshold and optimum values of oxidizable SOC were 3.2 and 11.2 g C/kg, respectively, whereas the threshold and optimum values for total SOC were 3.87 and 14.1 g C/kg, respectively. Among the different pools, less labile C was highly correlated (r = 0.5871) with the crop productivity, the computed threshold and optimum value for less labile C were 1.53 and 5.2 g C/kg, respectively

    Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression

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    Multiple, complex molecular events characterize cancer development and progression(1,2). Deciphering the molecular networks that distinguish organ- confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high- throughput liquid- and- gas- chromatography- based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer ( 42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N- methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non- invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine- N- methyl transferase, the enzyme that generates sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous sarcosine or knockdown of the enzyme that leads to sarcosine degradation, sarcosine dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.Early Detection Research Network ; National Institutes of Health ; MTTC ; Clinical Translational Science Award ; Fund for Discovery of the University of Michigan Comprehensive Cancer Center ; University of Michigan Cancer Biostatistics Training Grant ; Doris Duke Charitable FoundationWe thank J. Granger for help in manuscript preparation, J. Siddiqui and R. Varambally for help with the clinical database, and A. Vellaichamy and S. Pullela for technical assistance. We thank K. Pienta for access to metastatic prostate cancer samples from the University of Michigan Prostate SPORE rapid autopsy programme. This work is supported in part by the Early Detection Research Network (A.M.C., J.T.W.), National Institutes of Health (A.S., S.P., J.B., T.M.R., D.G., G.S.O. and A.M.C.) and an MTTC grant (G.S.O. and A.S.). A.M.C. is supported by a Clinical Translational Science Award from the Burroughs Welcome Foundation. A. S. is supported by a grant from the Fund for Discovery of the University of Michigan Comprehensive Cancer Center. L. M. P. is supported by the University of Michigan Cancer Biostatistics Training Grant. A. M. C and S. P. are supported by the Doris Duke Charitable Foundation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62661/1/nature07762.pd
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