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Sample records for amies gel transystem

  1. Obesity, starch digestion and amylase: association between copy number variants at human salivary (AMY1) and pancreatic (AMY2) amylase genes.

    Science.gov (United States)

    Carpenter, Danielle; Dhar, Sugandha; Mitchell, Laura M; Fu, Beiyuan; Tyson, Jess; Shwan, Nzar A A; Yang, Fengtang; Thomas, Mark G; Armour, John A L

    2015-06-15

    The human salivary amylase genes display extensive copy number variation (CNV), and recent work has implicated this variation in adaptation to starch-rich diets, and in association with body mass index. In this work, we use paralogue ratio tests, microsatellite analysis, read depth and fibre-FISH to demonstrate that human amylase CNV is not a smooth continuum, but is instead partitioned into distinct haplotype classes. There is a fundamental structural distinction between haplotypes containing odd or even numbers of AMY1 gene units, in turn coupled to CNV in pancreatic amylase genes AMY2A and AMY2B. Most haplotypes have one copy each of AMY2A and AMY2B and contain an odd number of copies of AMY1; consequently, most individuals have an even total number of AMY1. In contrast, haplotypes carrying an even number of AMY1 genes have rearrangements leading to CNVs of AMY2A/AMY2B. Read-depth and experimental data show that different populations harbour different proportions of these basic haplotype classes. In Europeans, the copy numbers of AMY1 and AMY2A are correlated, so that phenotypic associations caused by variation in pancreatic amylase copy number could be detected indirectly as weak association with AMY1 copy number. We show that the quantitative polymerase chain reaction (qPCR) assay previously applied to the high-throughput measurement of AMY1 copy number is less accurate than the measures we use and that qPCR data in other studies have been further compromised by systematic miscalibration. Our results uncover new patterns in human amylase variation and imply a potential role for AMY2 CNV in functional associations. © The Author 2015. Published by Oxford University Press.

  2. Obesity, starch digestion and amylase: association between copy number variants at human salivary (AMY1) and pancreatic (AMY2) amylase genes

    Science.gov (United States)

    Carpenter, Danielle; Dhar, Sugandha; Mitchell, Laura M.; Fu, Beiyuan; Tyson, Jess; Shwan, Nzar A.A.; Yang, Fengtang; Thomas, Mark G.; Armour, John A.L.

    2015-01-01

    The human salivary amylase genes display extensive copy number variation (CNV), and recent work has implicated this variation in adaptation to starch-rich diets, and in association with body mass index. In this work, we use paralogue ratio tests, microsatellite analysis, read depth and fibre-FISH to demonstrate that human amylase CNV is not a smooth continuum, but is instead partitioned into distinct haplotype classes. There is a fundamental structural distinction between haplotypes containing odd or even numbers of AMY1 gene units, in turn coupled to CNV in pancreatic amylase genes AMY2A and AMY2B. Most haplotypes have one copy each of AMY2A and AMY2B and contain an odd number of copies of AMY1; consequently, most individuals have an even total number of AMY1. In contrast, haplotypes carrying an even number of AMY1 genes have rearrangements leading to CNVs of AMY2A/AMY2B. Read-depth and experimental data show that different populations harbour different proportions of these basic haplotype classes. In Europeans, the copy numbers of AMY1 and AMY2A are correlated, so that phenotypic associations caused by variation in pancreatic amylase copy number could be detected indirectly as weak association with AMY1 copy number. We show that the quantitative polymerase chain reaction (qPCR) assay previously applied to the high-throughput measurement of AMY1 copy number is less accurate than the measures we use and that qPCR data in other studies have been further compromised by systematic miscalibration. Our results uncover new patterns in human amylase variation and imply a potential role for AMY2 CNV in functional associations. PMID:25788522

  3. [The AMY experiment

    International Nuclear Information System (INIS)

    1989-01-01

    The AMY experiment is one of three major experiments at TRISTAN which is studying the states the matter produced in electron positron annihilations in the center of mass energy range of 50--65GeV. It provides information between the lower energy facilities such as PEP and PETRA and the new facilities SLC and LEP which are designed to operate in the region of the Z 0 mass near 90GeV. In the region of the AMY experiment, interaction cross sections are near their minimum of about 100pb, making it difficult to acquire large data samples during typical running cycles. This last year has seen an accumulation of about 10---12pb -1 of integrated luminosity in the energy range from 58 to 61.7GeV. Despite this limited data sample, the AMY experiment has been extremely active in attempting to extract the minimum amount of information from the data. Some of the most significant results are discussed in this paper. 9 refs

  4. Monitoring with MonAMI: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Millar, A P; Stewart, G A [Department of Physics and Astronomy, University of Glasgow, University Avenue, Glasgow, G12 8QQ (United Kingdom); Cowan, G A [Department of Physics, University of Edinburgh, Edinburgh (United Kingdom)], E-mail: p.millar@physics.gla.ac.uk

    2008-07-15

    Computing resources in HEP are increasingly delivered utilising grid technologies, which presents new challenges in terms of monitoring. Monitoring involves the flow of information between different communities: the various resource-providers and the different user communities. The challenge is providing information so everyone can find what they need: from the local site administrators, regional operational centres through to end-users. To meet this challenge, MonAMI was developed. MonAMI aims to be a universal sensor framework with a plugin architecture. This plugin structure allows flexibility in what is monitored and how the gathered information is reported. MonAMI supports gathering statistics from many standard daemons, such as MySQL and Apache, and system data, such as network sockets and memory consumption. The gathered data can be sent to many monitoring systems, including Ganglia, Nagios, MonALISA and R-GMA. This flexibility allows MonAMI to be integrated into whatever monitoring system is being used. This avoids the current duplication of sensors and allows the gathered statistics to be presented within a greater diversity of monitoring systems. Using the MonAMI framework, sensors have been developed for the DPM and dCache storage systems, both common at HEP grid centres. The development of these tools specifically to tackle the challenges of high availability storage is described. We illustrate how MonAMI's architecture allows a single sensor to both deliver long term trend information and to trigger alarms in abnormal conditions. The use of MonAMI within the ScotGrid distributed Tier-2 is examined as a case study, illustrating both the ease with which MonAMI integrates into existing systems and helps provide a framework for extending monitoring where necessary.

  5. Monitoring with MonAMI: a case study

    International Nuclear Information System (INIS)

    Millar, A P; Stewart, G A; Cowan, G A

    2008-01-01

    Computing resources in HEP are increasingly delivered utilising grid technologies, which presents new challenges in terms of monitoring. Monitoring involves the flow of information between different communities: the various resource-providers and the different user communities. The challenge is providing information so everyone can find what they need: from the local site administrators, regional operational centres through to end-users. To meet this challenge, MonAMI was developed. MonAMI aims to be a universal sensor framework with a plugin architecture. This plugin structure allows flexibility in what is monitored and how the gathered information is reported. MonAMI supports gathering statistics from many standard daemons, such as MySQL and Apache, and system data, such as network sockets and memory consumption. The gathered data can be sent to many monitoring systems, including Ganglia, Nagios, MonALISA and R-GMA. This flexibility allows MonAMI to be integrated into whatever monitoring system is being used. This avoids the current duplication of sensors and allows the gathered statistics to be presented within a greater diversity of monitoring systems. Using the MonAMI framework, sensors have been developed for the DPM and dCache storage systems, both common at HEP grid centres. The development of these tools specifically to tackle the challenges of high availability storage is described. We illustrate how MonAMI's architecture allows a single sensor to both deliver long term trend information and to trigger alarms in abnormal conditions. The use of MonAMI within the ScotGrid distributed Tier-2 is examined as a case study, illustrating both the ease with which MonAMI integrates into existing systems and helps provide a framework for extending monitoring where necessary

  6. Amie Sluiter | NREL

    Science.gov (United States)

    dollar, cross-laboratory U.S. Department of Energy research projects. Excellent technical writing skills managing personnel and technical oversight. She is highly organized, with a technical background that lends itself to project participation and technical monitoring. Biofuels Sample Characterization Amie began

  7. Automated material interface (AMI) for mini-environment technology

    International Nuclear Information System (INIS)

    Wolf, M.; Fleming, J.; Mueller, R.; Pulaski, L.

    1993-01-01

    The Automated Material Inter-face or AMI presented here is a new method of automating the input/output of materials or products into mini-environments. The AMI concept and hardware, and preliminary data are presented to show that neither the automation hardware nor the product isolation carrier contribute any significant contamination to the product during the I/O process. Budgetary estimates are presented which support the AMI concept for cost effective manufacturing of advanced semiconductors and disk media

  8. ATLAS Metadata Interface (AMI), a generic metadata framework

    CERN Document Server

    Fulachier, Jerome; The ATLAS collaboration

    2016-01-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. We briefly describe the architecture, the main services and the benefits of using AMI in big collaborations, especially for high energy physics. We focus on the recent improvements, for instance: the lightweight clients (Python, Javascript, C++), the new smart task server system and the Web 2.0 AMI framework for simplifying the development of metadata-oriented web interfaces.

  9. Obesity as an Early Symptom of the AMIS Syndrome

    Directory of Open Access Journals (Sweden)

    W. Wayne Lautt

    2014-10-01

    Full Text Available We review evidence that the AMIS (Absence of Meal-induced Insulin Sensitization syndrome describes a paradigm fundamental to development of obesity. The hypoglycemic response to a pulse of insulin is doubled after a meal as a result of Hepatic Insulin Sensitizing Substance (HISS, released from the liver to act selectively on muscle, heart and kidney. In the absence of HISS action, the hypoglycemic response to insulin is the same as in the fasted state, and only half of what it should be. Postprandial hyperglycemia ensues, with compensatory hyperinsulinemia, resultant hyperlipidemia and elevated free radical stress. Storage of nutrient energy shifts from glycogen in muscle to fat. Chronic AMIS results in adiposity, occurs with age, is accelerated with sucrose supplement, and prevented by a synergistic antioxidant. Exercise reverses AMIS, as do pharmaceuticals that mimic the “feeding signals”. The AMIS syndrome develops as a sequence of pathologies based on the consequences of absence of HISS action, including adiposity as the earliest symptom. Cardiac dysfunction, hypertension, hypercholesterolemia, and fatty liver are related to lack of HISS action. The AMIS syndrome hypothesis is mechanistic-based and accounts for the major pathologies associated with prediabetes, obesity, diabetes and metabolic syndrome. AMIS can be diagnosed, prevented and treated.

  10. ATLAS Metadata Interface (AMI), a generic metadata framework

    Science.gov (United States)

    Fulachier, J.; Odier, J.; Lambert, F.; ATLAS Collaboration

    2017-10-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. We briefly describe the architecture, the main services and the benefits of using AMI in big collaborations, especially for high energy physics. We focus on the recent improvements, for instance: the lightweight clients (Python, JavaScript, C++), the new smart task server system and the Web 2.0 AMI framework for simplifying the development of metadata-oriented web interfaces.

  11. ATLAS Metadata Interface (AMI), a generic metadata framework

    CERN Document Server

    AUTHOR|(SzGeCERN)573735; The ATLAS collaboration; Odier, Jerome; Lambert, Fabian

    2017-01-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. We briefly describe the architecture, the main services and the benefits of using AMI in big collaborations, especially for high energy physics. We focus on the recent improvements, for instance: the lightweight clients (Python, JavaScript, C++), the new smart task server system and the Web 2.0 AMI framework for simplifying the development of metadata-oriented web interfaces.

  12. Broadband PLC for Clustered Advanced Metering Infrastructure (AMI Architecture

    Directory of Open Access Journals (Sweden)

    Augustine Ikpehai

    2016-07-01

    Full Text Available Advanced metering infrastructure (AMI subsystems monitor and control energy distribution through exchange of information between smart meters and utility networks. A key challenge is how to select a cost-effective communication system without compromising the performance of the applications. Current communication technologies were developed for conventional data networks with different requirements. It is therefore necessary to investigate how much of existing communication technologies can be retrofitted into the new energy infrastructure to cost-effectively deliver acceptable level of service. This paper investigates broadband power line communications (BPLC as a backhaul solution in AMI. By applying the disparate traffic characteristics of selected AMI applications, the network performance is evaluated. This study also examines the communication network response to changes in application configurations in terms of packet sizes. In each case, the network is stress-tested and performance is assessed against acceptable thresholds documented in the literature. Results show that, like every other communication technology, BPLC has certain limitations; however, with some modifications in the network topology, it indeed can fulfill most AMI traffic requirements for flexible and time-bounded applications. These opportunities, if tapped, can significantly improve fiscal and operational efficiencies in AMI services. Simulation results also reveal that BPLC as a backhaul can support flat and clustered AMI structures with cluster size ranging from 1 to 150 smart meters.

  13. ARM MJO Investigation Experiment on Gan Island (AMIE-Gan) Science Plan

    Energy Technology Data Exchange (ETDEWEB)

    Long, CL; Del Genio, A; Deng, M; Fu, X; Gustafson, W; Houze, R; Jakob, C; Jensen, M; Johnson, R; Liu, X; Luke, E; May, P; McFarlane, S; Minnis, P; Schumacher, C; Vogelmann, A; Wang, Y; Webster, P; Xie, S; Zhang, C

    2011-04-11

    The overarching campaign, which includes the ARM Mobile Facility 2 (AMF2) deployment in conjunction with the Dynamics of the Madden-Julian Oscillation (DYNAMO) and the Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011 (CINDY2011) campaigns, is designed to test several current hypotheses regarding the mechanisms responsible for Madden-Julian Oscillation (MJO) initiation and propagation in the Indian Ocean area. The synergy between the proposed AMF2 deployment with DYNAMO/CINDY2011, and the corresponding funded experiment on Manus, combine for an overarching ARM MJO Investigation Experiment (AMIE) with two components: AMF2 on Gan Island in the Indian Ocean (AMIE-Gan), where the MJO initiates and starts its eastward propagation; and the ARM Manus site (AMIE-Manus), which is in the general area where the MJO usually starts to weaken in climate models. AMIE-Gan will provide measurements of particular interest to Atmospheric System Research (ASR) researchers relevant to improving the representation of MJO initiation in climate models. The framework of DYNAMO/CINDY2011 includes two proposed island-based sites and two ship-based locations forming a square pattern with sonde profiles and scanning precipitation and cloud radars at both island and ship sites. These data will be used to produce a Variational Analysis data set coinciding with the one produced for AMIE-Manus. The synergy between AMIE-Manus and AMIE-Gan will allow studies of the initiation, propagation, and evolution of the convective cloud population within the framework of the MJO. As with AMIE-Manus, AMIE-Gan/DYNAMO also includes a significant modeling component geared toward improving the representation of MJO initiation and propagation in climate and forecast models. This campaign involves the deployment of the second, marine-capable, AMF; all of the included measurement systems; and especially the scanning and vertically pointing radars. The campaign will include sonde

  14. AmyI-1-18, a cationic α-helical antimicrobial octadecapeptide derived from α-amylase in rice, inhibits the translation and folding processes in a protein synthesis system.

    Science.gov (United States)

    Taniguchi, Masayuki; Ochiai, Akihito; Fukuda, Shun; Sato, Teppei; Saitoh, Eiichi; Kato, Tetsuo; Tanaka, Takaaki

    2016-10-01

    In our previous study, we used a cell-free rapid translation system (RTS), which is an in vitro protein synthesis system based on Escherichia coli lysate, for evaluating the inhibition of green fluorescent protein (GFP) synthesis by pyrrhocoricin. In this study, using an RTS, we evaluated the inhibition of GFP synthesis by AmyI-1-18, an antimicrobial octadecapeptide. We found that, similarly to pyrrhocoricin, AmyI-1-18 inhibited GFP synthesis in the RTS in a concentration-dependent manner. In addition, the blockage of transcription and translation steps in the RTS was individually estimated using RT-PCR after gene expression to determine the mRNA products and using sodium dodecyl sulfate-polyacrylamide gel electrophoresis to determine the amounts of GFP expressed from purified mRNA, respectively. The results demonstrated that the inhibition of GFP synthesis by AmyI-1-18 did not occur at the transcription step but rather at the translation step. Furthermore, we assessed the inhibition of DnaK-mediated refolding of chemically denatured luciferase by AmyI-1-18; AmyI-1-18 inhibited the protein folding activity of the ATP-dependent DnaK/DnaJ molecular chaperone system in a concentration-dependent manner. Surface plasmon resonance (SPR) analysis showed that AmyI-1-18 strongly bound to RNA with a KD value of 1.4 × 10(-8) M but not to DNA and that AmyI-1-18 specifically bound to DnaK with a KD value of 4.4 × 10(-6) M. These SPR analysis results supported the results obtained in both the RTS and the molecular chaperone system. These results demonstrated that both RNA and DnaK are most likely the target of AmyI-1-18 in the protein synthesis system. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. Arabidopsis thaliana AMY3 Is a Unique Redox-regulated Chloroplastic α-Amylase

    DEFF Research Database (Denmark)

    Seung, David; Thalmann, Matthias; Sparla, Francesca

    2013-01-01

    α-Amylases are glucan hydrolases that cleave α-1,4-glucosidic bonds in starch. In vascular plants, α-amylases can be classified into three subfamilies. Arabidopsis has one member of each subfamily. Among them, only AtAMY3 is localized in the chloroplast. We expressed and purified AtAMY3 from...... to be dependent on a conserved aspartic acid residue (Asp666), identified as the catalytic nucleophile in other plant α-amylases such as the barley AMY1. AtAMY3 released small linear and branched glucans from Arabidopsis starch granules, and the proportion of branched glucans increased after the predigestion...

  16. Evolution of the architecture of the ATLAS Metadata Interface (AMI)

    Science.gov (United States)

    Odier, J.; Aidel, O.; Albrand, S.; Fulachier, J.; Lambert, F.

    2015-12-01

    The ATLAS Metadata Interface (AMI) is now a mature application. Over the years, the number of users and the number of provided functions has dramatically increased. It is necessary to adapt the hardware infrastructure in a seamless way so that the quality of service re - mains high. We describe the AMI evolution since its beginning being served by a single MySQL backend database server to the current state having a cluster of virtual machines at French Tier1, an Oracle database at Lyon with complementary replication to the Oracle DB at CERN and AMI back-up server.

  17. Expression, purification and functional characterization of AmiA of acetamidase operon of Mycobacterium smegmatis.

    Science.gov (United States)

    Sundararaman, Balaji; Palaniyandi, Kannan; Venkatesan, Arunkumar; Narayanan, Sujatha

    2014-11-01

    Regulation of gene expression is one of the mechanisms of virulence in pathogenic organisms. In this context, we would like to understand the gene regulation of acetamidase enzyme of Mycobacterium smegmatis, which is the first reported inducible enzyme in mycobacteria. The acetamidase is highly inducible and the expression of this enzyme is increased 100-fold when the substrate acetamide is added. The acetamidase structural gene (amiE) is found immediately downstream of three predicted open reading frames (ORFs). Three of these genes along with a divergently expressed ORF are predicted to form an operon and involved in the regulation of acetamidase enzyme. Here we report expression, purification and functional characterization of AmiA which is one of these predicted ORFs. Electrophoretic mobility shift assays showed that AmiA binds to the region between the amiA and amiD near the predicted promoter (P2). Over-expression of AmiA significantly lowered the expression of acetamidase compared to the wild type as demonstrated by qRT-PCR and SDS-PAGE. We conclude that AmiA binds near P2 promoter and acts as a repressor in the regulation of acetamidase operon. The described work is a further step forward toward broadening the knowledge on understanding of the complex gene regulatory mechanism of Mycobacterium sp. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. [Urs Fischer: faux amis : documentation d'exposition

    OpenAIRE

    2016-01-01

    Tiré du site internet des Musées d'art et d'histoire (www.ville-geneve.ch/mah): "Urs Fischer - Faux Amis propose une sélection inédite d'œuvres de la collection Dakis Joannou, présentée pour la première fois au Musée d'art et d'histoire de Genève. Conçue par le commissaire Massimiliano Gioni comme une synthèse inhabituelle entre une présentation monographique et une exposition de groupe, Faux Amis réunit un ensemble d'œuvres signées Urs Fischer (né en 1973), l'un des artistes suisses les plus...

  19. Are AMI patients with comorbid mental illness more likely to be admitted to hospitals with lower quality of AMI care?

    Directory of Open Access Journals (Sweden)

    Xueya Cai

    Full Text Available Older patients with comorbid mental illness are shown to receive less appropriate care for their medical conditions. This study analyzed Medicare patients hospitalized for acute myocardial infarction (AMI and determined whether those with comorbid mental illness were more likely to present to hospitals with lower quality of AMI care.Retrospective analyses of Medicare claims in 2008. Hospital quality was measured using the five "Hospital Compare" process indicators (aspirin at admission/discharge, beta-blocker at admission/discharge, and angiotension-converting enzyme inhibitor or angiotension receptor blocker for left ventricular dysfunction. Multinomial logit model determined the association of mental illness with admission to low-quality hospitals (rank of the composite process score 90(th percentile, compared to admissions to other hospitals with medium quality. Multivariate analyses further determined the effects of hospital type and mental diagnosis on outcomes.Among all AMI admissions to 2,845 hospitals, 41,044 out of 287,881 patients were diagnosed with mental illness. Mental illness predicted a higher likelihood of admission to low-quality hospitals (unadjusted rate 2.9% vs. 2.0%; adjusted odds ratio [OR]1.25, 95% confidence interval [CI] 1.17-1.34, p<0.01, and an equal likelihood to high-quality hospitals (unadjusted rate 9.8% vs. 10.3%; adjusted OR 0.97, 95% CI 0.93-1.01, p = 0.11. Both lower hospital quality and mental diagnosis predicted higher rates of 30-day readmission, 30-day mortality, and 1-year mortality.Among Medicare myocardial infarction patients, comorbid mental illness was associated with an increased risk for admission to lower-quality hospitals. Both lower hospital quality and mental illness predicted worse post-AMI outcomes.

  20. AmI and deployment considerations in AAL services provision for elderly independent living: the MonAMI project.

    Science.gov (United States)

    Falcó, Jorge L; Vaquerizo, Esteban; Lain, Luis; Artigas, Jose Ignacio; Ibarz, Alejandro

    2013-07-12

    The MonAMI project aims to investigate the feasibility of the deployment of open platforms for Ambient Assisted Living (AAL) services provision based on Ambient Intelligence (AmI) and to test user acceptance and the usability of the services. Services were designed to provide support in the areas of environmental control, security, well-being and leisure. These services were installed and evaluated in a Spanish geriatric residence. The participants included elderly persons with disabilities, nursing home care givers and informal carers. The concept of the open platform proved to be satisfactory for the provision of the services in a context aware framework. Furthermore, the usability of the technology was viewed positively and the overall results indicate that this system has the potential to prolong independent living at home for elderly people with disabilities. Deployment was proven successful and awareness of open-platform AAL service delivery was raised in local communities throughout Europe.

  1. AmI and Deployment Considerations in AAL Services Provision for Elderly Independent Living: The MonAMI Project

    Directory of Open Access Journals (Sweden)

    Alejandro Ibarz

    2013-07-01

    Full Text Available The MonAMI project aims to investigate the feasibility of the deployment of open platforms for Ambient Assisted Living (AAL services provision based on Ambient Intelligence (AmI and to test user acceptance and the usability of the services. Services were designed to provide support in the areas of environmental control, security, well-being and leisure. These services were installed and evaluated in a Spanish geriatric residence. The participants included elderly persons with disabilities, nursing home care givers and informal carers. The concept of the open platform proved to be satisfactory for the provision of the services in a context aware framework. Furthermore, the usability of the technology was viewed positively and the overall results indicate that this system has the potential to prolong independent living at home for elderly people with disabilities. Deployment was proven successful and awareness of open-platform AAL service delivery was raised in local communities throughout Europe.

  2. Comparison of AMI-25 enhanced MRI and helical dynamic CT in the detection of hepatic lesions

    International Nuclear Information System (INIS)

    Saitou, Kazuhiro; Matsuda, Hiromichi; Fukushima, Hiroaki; Kanzaki, Hiroshi; Hirose, Takashi; Karizaki, Dai; Abe, Kimihiko; Amino, Saburou

    1994-01-01

    We performed AMI-25 enhanced MRI and helical dynamic CT in 12 cases of hepatic lesions. Nine of these were hepatocellular carcinomas. Two cases were metastatic liver tumors (the primary lesion was gastric in one and the other was gallbladder cancer). One case was suspected to be adenomatous hyperplasia. Thirty-two lesions were detected in T2-weighted SE images before AMI-25 administration, while 46 lesions were detected in AMI-25 enhanced MRI images. In particular, AMI-25 enhanced MRI was superior to plain MRI in lesions less than 10 mm in size. A total of 48 lesions were detected in helical dynamic CT. Although AMI-25 enhanced MRI almost equaled helical dynamic CT in the detection of liver tumors, helical dynamic CT was slightly superior to AMI-25 enhanced MRI in the detection of subphrenic lesions. It was possible to know the hemodynamics in each hepatic lesion by helical dynamic CT. AMI-25 enhanced MRI was useful to know the inclusion of reticuloendothelial system, and that yielded different diagnoses in adenomatous hyperplasia and well differentiated hepatocellular carcinoma. Helical dynamic CT was useful for qualitative diagnosis. Both AMI-25 enhanced MRI and helical dynamic CT contributed to the detection of liver tumor and qualitative diagnosis. (author)

  3. Medium dependent dual turn on/turn off fluorescence sensing for Cu2 + ions using AMI/SDS assemblies

    Science.gov (United States)

    Gujar, Varsha B.; Ottoor, Divya

    2017-02-01

    Behavior of Amiloride (AMI) as a metal ion sensor in anionic surfactant assemblies of varying concentrations at different pH is depicted in this work. From a non-sensor fluorophore, AMI has been transformed in to a tunable fluorosensor for Cu2 + ions in various SDS concentrations. At premicellar concentration of SDS, ion-pair complex is expected to be formed between AMI and SDS due to electrostatic interactions between them. However at CMC concentrations of SDS, fluorescence intensity of AMI is greatly enhanced with red shift in emission, due to the incorporation of AMI molecule in the hydrophobic micellar interface. The behavior of metal sensing by AMI-SDS assemblies gives rise to several interesting observations. Micellation of SDS has been greatly enhanced by increasing copper ion concentrations, as these counter ions screens the charge on monomers of SDS which lead to the aggregation at premicellar concentrations only. Concentrations and pH dependent discrete trends of interactions between SDS-AMI and SDS-Cu2 + ions, have given tunable fluorescence responses (fluorescence turn on/turn off) of AMI for added Cu2 + ions. The electrostatic interaction between the metal cations and the anionic surfactants is the driving force for bringing the metal ions near to the vicinity of micelle where AMI resides. Thus, a comprehensive understanding of the mechanism related to the 'turn on-turn off' fluorescence response of AMI with respect to pH and SDS concentration for effective Cu2 + ion sensing is illustrated in this work.

  4. AMIE Camera System on board SMART-1

    Science.gov (United States)

    Josset, J. L.; Beauvivre, S.; Amie Team

    The Advanced Moon micro-Imager Experiment AMIE on board ESA SMART-1 the first European mission to the Moon launched on 27th September 2003 is an imaging system with scientific technical and public outreach oriented objectives The science objectives are to image the Lunar Poles permanent shadow areas ice deposit eternal light crater rims ancient Lunar Non-mare volcanism local spectro-photometry and physical state of the lunar sur-face and to map high latitudes regions south mainly at far side South Pole Aitken basin The technical objectives are to perform a laserlink experiment detec-tion of laser beam emitted by ESA Tenerife ground station flight demonstration of new technologies and on-board autonomy navigation The public outreach and educational objectives are to promote planetary exploration We present the AMIE instrument and perfomances with respect to the first results

  5. Ami - The chemist's amanuensis.

    Science.gov (United States)

    Brooks, Brian J; Thorn, Adam L; Smith, Matthew; Matthews, Peter; Chen, Shaoming; O'Steen, Ben; Adams, Sam E; Townsend, Joe A; Murray-Rust, Peter

    2011-10-14

    The Ami project was a six month Rapid Innovation project sponsored by JISC to explore the Virtual Research Environment space. The project brainstormed with chemists and decided to investigate ways to facilitate monitoring and collection of experimental data.A frequently encountered use-case was identified of how the chemist reaches the end of an experiment, but finds an unexpected result. The ability to replay events can significantly help make sense of how things progressed. The project therefore concentrated on collecting a variety of dimensions of ancillary data - data that would not normally be collected due to practicality constraints. There were three main areas of investigation: 1) Development of a monitoring tool using infrared and ultrasonic sensors; 2) Time-lapse motion video capture (for example, videoing 5 seconds in every 60); and 3) Activity-driven video monitoring of the fume cupboard environs.The Ami client application was developed to control these separate logging functions. The application builds up a timeline of the events in the experiment and around the fume cupboard. The videos and data logs can then be reviewed after the experiment in order to help the chemist determine the exact timings and conditions used.The project experimented with ways in which a Microsoft Kinect could be used in a laboratory setting. Investigations suggest that it would not be an ideal device for controlling a mouse, but it shows promise for usages such as manipulating virtual molecules.

  6. Complex Copy Number Variation of AMY1 does not Associate with Obesity in two East Asian Cohorts.

    Science.gov (United States)

    Yong, Rita Y Y; Mustaffa, Su'Aidah B; Wasan, Pavandip S; Sheng, Liang; Marshall, Christian R; Scherer, Stephen W; Teo, Yik-Ying; Yap, Eric P H

    2016-07-01

    The human amylase gene locus at chromosome 1p21.1 is structurally complex. This region contains two pancreatic amylase genes, AMY2B, AMY2A, and a salivary gene AMY1. The AMY1 gene harbors extensive copy number variation (CNV), and recent studies have implicated this variation in adaptation to starch-rich diets and in association to obesity for European and Asian populations. In this study, we showed that by combining quantitative PCR and digital PCR, coupled with careful experimental design and calibration, we can improve the resolution of genotyping CNV with high copy numbers (CNs). In two East Asian populations of Chinese and Malay ethnicity studied, we observed a unique non-normal distribution of AMY1 diploid CN genotypes with even:odd CNs ratio of 4.5 (3.3-4.7), and an association between the common AMY2A CN = 2 genotype and odd CNs of AMY1, that could be explained by the underlying haplotypic structure. In two further case-control cohorts (n = 932 and 145, for Chinese and Malays, respectively), we did not observe the previously reported association between AMY1 and obesity or body mass index. Improved methods for accurately genotyping multiallelic CNV loci and understanding the haplotype complexity at the AMY1 locus are necessary for population genetics and association studies. © 2016 WILEY PERIODICALS, INC.

  7. Rethinking the starch digestion hypothesis for AMY1 copy number variation in humans.

    Science.gov (United States)

    Fernández, Catalina I; Wiley, Andrea S

    2017-08-01

    Alpha-amylase exists across taxonomic kingdoms with a deep evolutionary history of gene duplications that resulted in several α-amylase paralogs. Copy number variation (CNV) in the salivary α-amylase gene (AMY1) exists in many taxa, but among primates, humans appear to have higher average AMY1 copies than nonhuman primates. Additionally, AMY1 CNV in humans has been associated with starch content of diets, and one known function of α-amylase is its involvement in starch digestion. Thus high AMY1 CNV is considered to result from selection favoring more efficient starch digestion in the Homo lineage. Here, we present several lines of evidence that challenge the hypothesis that increased AMY1 CNV is an adaptation to starch consumption. We observe that α- amylase plays a very limited role in starch digestion, with additional steps required for starch digestion and glucose metabolism. Specifically, we note that α-amylase hydrolysis only produces a minute amount of free glucose with further enzymatic digestion and glucose absorption being rate-limiting steps for glucose availability. Indeed α-amylase is nonessential for starch digestion since sucrase-isomaltase and maltase-glucoamylase can hydrolyze whole starch granules while releasing glucose. While higher AMY1 CN and CNV among human populations may result from natural selection, existing evidence does not support starch digestion as the major selective force. We report that in humans α-amylase is expressed in several other tissues where it may have potential roles of evolutionary significance. © 2017 Wiley Periodicals, Inc.

  8. Characteristics of myocardial perfusion imaging and coronary artery angiography in patients of NIDDM complicated with AMI

    International Nuclear Information System (INIS)

    Zhao Peiqin; Zhao Jinhua; Qin Mingzhao; Dai HaoJie; Zhang Runwu; Xiao Fen

    2001-01-01

    Objective: To investigate the characteristic changes of myocardial perfusion imaging and coronary artery angiography in patients of acute myocardial infarction (AMI) with underlined type 2 diabetes mellitus. Methods: 25 type 2 diabetes mellitus patients were enrolled for having clinical manifestation of AMI. Ten inpatients with AMI of simple coronary heart disease origin were served as controls. All subjects underwent both myocardial perfusion imagings (resting and nitroglycerine invention) and coronary artery angiography. Results: Compared to controls (40%), type 2 diabetes mellitus + AMI group had higher rate of multivessel disease (60%). For type 2 diabetes mellitus + AMI patients, 129/400 segments (32.25%) showed fixed defect, 25/160 segments (15.62%) in controls. Conclusions: For type 2 diabetes mellitus + AMI group, myocardial perfusion defects are widely distributed and multivessel or severe stenosis is more often presented. Good correlation exists between abnormal segments and angiographic lesions in both the number of segments involved and the severity of the lesions. Radionuclide myocardial perfusion is therefore considered a useful screening test not inferior to angiography, especially for those who are not tolerant enough to undergoing angiography

  9. Deploying the ATLAS Metadata Interface (AMI) on the cloud with Jenkins

    Science.gov (United States)

    Lambert, F.; Odier, J.; Fulachier, J.; ATLAS Collaboration

    2017-10-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. AMI is used by the ATLAS production system, therefore the service must guarantee a high level of availability. We describe our monitoring and administration systems, and the Jenkins-based strategy used to dynamically test and deploy cloud OpenStack nodes on demand.

  10. Deploying the ATLAS Metadata Interface (AMI) on the cloud with Jenkins.

    CERN Document Server

    AUTHOR|(SzGeCERN)637120; The ATLAS collaboration; Odier, Jerome; Fulachier, Jerome

    2017-01-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. AMI is used by the ATLAS production system, therefore the service must guarantee a high level of availability. We describe our monitoring and administration systems, and the Jenkins-based strategy used to dynamically test and deploy cloud OpenStack nodes on demand.

  11. Now that California has AMI, what can the state do with it?

    International Nuclear Information System (INIS)

    Woo, C.K.; Kollman, E.; Orans, R.; Price, S.; Horii, B.

    2008-01-01

    Recognizing the lack of retail-demand response, a state regulator, such as the California Public Utilities Commission (CPUC), seeks tariff proposals that transmit wholesale price signals to a local distribution company's (LDC) retail customers. To enable these proposals, the CPUC has authorized funding for advanced metering infrastructure (AMI) for two investor-owned LDCs. Assuming regulatory approval of the third LDC's application, the state's US$4.28 billion AMI investment will aid new rate designs for 11.3 million electricity customers. Now that California has AMI, what can the state do with it? With AMI in hand, an LDC can implement service options that can further the state's energy initiatives, ranging from resource adequacy requirement (RAR) to greenhouse gas (GHG) emissions reduction. These options can efficiently allocate limited capacity based on each customer's willingness to pay, without the unnecessary distinction between price rationing and reliability differentiation. They can be Pareto superior, welfare dominating the default tariffs that apply to these customers. A case in point is the generalized demand subscription service (GDSS) option proposed in this paper. However, it is unclear whether the option will find wide customer acceptance, without an LDC's intensive customer education and marketing efforts

  12. Low AMY1 Gene Copy Number Is Associated with Increased Body Mass Index in Prepubertal Boys.

    Directory of Open Access Journals (Sweden)

    M Loredana Marcovecchio

    Full Text Available Genome-wide association studies have identified more than 60 single nucleotide polymorphisms associated with Body Mass Index (BMI. Additional genetic variants, such as copy number variations (CNV, have also been investigated in relation to BMI. Recently, the highly polymorphic CNV in the salivary amylase (AMY1 gene, encoding an enzyme implicated in the first step of starch digestion, has been associated with obesity in adults and children. We assessed the potential association between AMY1 copy number and a wide range of BMI in a population of Italian school-children.744 children (354 boys, 390 girls, mean age (±SD: 8.4±1.4years underwent anthropometric assessments (height, weight and collection of saliva samples for DNA extraction. AMY1 copies were evaluated by quantitative PCR.A significant increase of BMI z-score by decreasing AMY1 copy number was observed in boys (β: -0.117, p = 0.033, but not in girls. Similarly, waist circumference (β: -0.155, p = 0.003, adjusted for age was negatively influenced by AMY1 copy number in boys. Boys with 8 or more AMY1 copy numbers presented a significant lower BMI z-score (p = 0.04 and waist circumference (p = 0.01 when compared to boys with less than 8 copy numbers.In this pediatric-only, population-based study, a lower AMY1 copy number emerged to be associated with increased BMI in boys. These data confirm previous findings from adult studies and support a potential role of a higher copy number of the salivary AMY1 gene in protecting from excess weight gain.

  13. Clinical significance of changes of plasma ET and NPY levels after treatment in patients with AMI

    International Nuclear Information System (INIS)

    Zhou Jinbao

    2005-01-01

    Objective: To investigate the changes of plasma ET and NPY levels in patients with AMI. Methods: Plasma ET and NPY levels were dynamically determined in 36 patients with AMI right after establishment of diagnosis and 8h, 24h, 4ph, 72h, 7d, 14d later. Levels in 35 healthy individuals were taken as control. Results: Before treatment was initiated, the levels of Et and Np in patients with AMI were significantly higher than those in controls (P <0.01). After one week of treatment, the levels dropped toward normal. Conclusion: Dynamic measurement of plasma ET and NPY levels in patients with AMI is of clinical importance. (authors)

  14. AMiBA: BROADBAND HETERODYNE COSMIC MICROWAVE BACKGROUND INTERFEROMETRY

    International Nuclear Information System (INIS)

    Chen, M.-T.; Li, C.-T.; Hwang, Y.-J.; Jiang Homin; Altamirano, Pablo; Chang, C.-H.; Chang, S.-H.; Chang, S.-W.; Han, C.-C.; Huang, Y.-D.; Kubo, Derek; Martin-Cocher, Pierre; Oshiro, Peter; Raffin, Philippe; Wei Tashun; Chiueh, T.-D.; Chu, T.-H.; Wang Huei; Kesteven, Michael; Wilson, Warwick

    2009-01-01

    The Y. T. Lee Array for Microwave Background (AMiBA) has reported the first results on the detection of galaxy clusters via the Sunyaev-Zel'dovich effect. The objectives required small reflectors in order to sample large-scale structures (20'), while interferometry provided modest resolutions (2'). With these constraints, we designed for the best sensitivity by utilizing the maximum possible continuum bandwidth matched to the atmospheric window at 86-102 GHz, with dual polarizations. A novel wide-band analog correlator was designed that is easily expandable for more interferometer elements. Monolithic millimeter-wave integrated circuit technology was used throughout as much as possible in order to miniaturize the components and to enhance mass production. These designs will find application in other upcoming astronomy projects. AMiBA is now in operation since 2006, and we are in the process to expand the array from seven to 13 elements.

  15. Deploying the ATLAS Metadata Interface (AMI) on the cloud with Jenkins

    CERN Document Server

    Lambert, Fabian; The ATLAS collaboration

    2016-01-01

    The ATLAS Metadata Interface (AMI) is a mature application of more than 15 years of existence. Mainly used by the ATLAS experiment at CERN, it consists of a very generic tool ecosystem for metadata aggregation and cataloguing. AMI is used by the ATLAS production system, therefore the service must guarantee a high level of availability. We describe our monitoring system and the Jenkins-based strategy used to dynamically test and deploy cloud OpenStack nodes on demand. Moreover, we describe how to switch to a distant replica in case of downtime.

  16. Beneficial effect of a high number of copies of salivary amylase AMY1 gene on obesity risk in Mexican children.

    Science.gov (United States)

    Mejía-Benítez, María A; Bonnefond, Amélie; Yengo, Loïc; Huyvaert, Marlène; Dechaume, Aurélie; Peralta-Romero, Jesús; Klünder-Klünder, Miguel; García Mena, Jaime; El-Sayed Moustafa, Julia S; Falchi, Mario; Cruz, Miguel; Froguel, Philippe

    2015-02-01

    Childhood obesity is a major public health problem in Mexico, affecting one in every three children. Genome-wide association studies identified genetic variants associated with childhood obesity, but a large missing heritability remains to be elucidated. We have recently shown a strong association between a highly polymorphic copy number variant encompassing the salivary amylase gene (AMY1 also known as AMY1A) and obesity in European and Asian adults. In the present study, we aimed to evaluate the association between AMY1 copy number and obesity in Mexican children. We evaluated the number of AMY1 copies in 597 Mexican children (293 obese children and 304 normal weight controls) through highly sensitive digital PCR. The effect of AMY1 copy number on obesity status was assessed using a logistic regression model adjusted for age and sex. We identified a marked effect of AMY1 copy number on reduced risk of obesity (OR per estimated copy 0.84, with the number of copies ranging from one to 16 in this population; p = 4.25 × 10(-6)). The global association between AMY1 copy number and reduced risk of obesity seemed to be mostly driven by the contribution of the highest AMY1 copy number. Strikingly, all children with >10 AMY1 copies were normal weight controls. Salivary amylase initiates the digestion of dietary starch, which is highly consumed in Mexico. Our current study suggests putative benefits of high number of AMY1 copies (and related production of salivary amylase) on energy metabolism in Mexican children.

  17. A Power Planning Algorithm Based on RPL for AMI Wireless Sensor Networks.

    Science.gov (United States)

    Miguel, Marcio L F; Jamhour, Edgard; Pellenz, Marcelo E; Penna, Manoel C

    2017-03-25

    The advanced metering infrastructure (AMI) is an architecture for two-way communication between electric, gas and water meters and city utilities. The AMI network is a wireless sensor network that provides communication for metering devices in the neighborhood area of the smart grid. Recently, the applicability of a routing protocol for low-power and lossy networks (RPL) has been considered in AMI networks. Some studies in the literature have pointed out problems with RPL, including sub-optimal path selection and instability. In this paper, we defend the viewpoint that careful planning of the transmission power in wireless RPL networks can significantly reduce the pointed problems. This paper presents a method for planning the transmission power in order to assure that, after convergence, the size of the parent set of the RPL nodes is as close as possible to a predefined size. Another important feature is that all nodes in the parent set offer connectivity through links of similar quality.

  18. amiA is a negative regulator of acetamidase expression in Mycobacterium smegmatis

    Directory of Open Access Journals (Sweden)

    Turner Jane

    2001-08-01

    Full Text Available Abstract Background The acetamidase of Mycobacterium smegmatis is a highly inducible enzyme. Expression of this enzyme is increased 100-fold when the substrate acetamide is present. The acetamidase gene is found immediately downstream of three open reading frames. Two of these are proposed to be involved in regulation. Results We constructed a deletion mutant in one of the upstream ORFs (amiA. This mutant (Mad1 showed a constitutively high level of acetamidase expression. We identified four promoters in the upstream region using a β-galactosidase reporter gene. One of these (P2 was inducible in the wild-type, but was constitutively active in Mad1. Conclusions These results demonstrate that amiA encodes a negative regulatory protein which interacts with P2. Since amiA has homology to DNA-binding proteins, it is likely that it exerts the regulatory effect by binding to the promoter to prevent transcription.

  19. Copy number variation of human AMY1 is a minor contributor to variation in salivary amylase expression and activity.

    Science.gov (United States)

    Carpenter, Danielle; Mitchell, Laura M; Armour, John A L

    2017-02-20

    Salivary amylase in humans is encoded by the copy variable gene AMY1 in the amylase gene cluster on chromosome 1. Although the role of salivary amylase is well established, the consequences of the copy number variation (CNV) at AMY1 on salivary amylase protein production are less well understood. The amylase gene cluster is highly structured with a fundamental difference between odd and even AMY1 copy number haplotypes. In this study, we aimed to explore, in samples from 119 unrelated individuals, not only the effects of AMY1 CNV on salivary amylase protein expression and amylase enzyme activity but also whether there is any evidence for underlying difference between the common haplotypes containing odd numbers of AMY1 and even copy number haplotypes. AMY1 copy number was significantly correlated with the variation observed in salivary amylase production (11.7% of variance, P structure may affect expression, but this was not significant in our data.

  20. Coastal wave measurements during passage of tropical storm Amy

    Science.gov (United States)

    Morris, W. D.

    1977-01-01

    Aerial photographic and laser profilometer data of waves generated by tropical storm Amy are presented. The data mission consisted primarily of two legs, one in the direction of the wind waves, and the second along the direction of swell propagation, using Jennette's Pier at Nags Head, North Carolina, as a focal point. At flight time, Amy's center was 512 nmi from shore and had maximum winds of 60 knots. The storm's history is presented, along with a satellite photograph, showing the extent of the storm on the day of the flight. Flight ground tracks are presented along with sample aerial photographs of the wave conditions showing approximate wavelength and direction. Sample wave energy spectra are presented both from the laser profilometer onboard the aircraft, and from the Corps of Engineers Research Center (CERC) shore gauge at Nags Head, North Carolina.

  1. Migration of the ATLAS Metadata Interface (AMI) to Web 2.0 and cloud

    Science.gov (United States)

    Odier, J.; Albrand, S.; Fulachier, J.; Lambert, F.

    2015-12-01

    The ATLAS Metadata Interface (AMI), a mature application of more than 10 years of existence, is currently under adaptation to some recently available technologies. The web interfaces, which previously manipulated XML documents using XSL transformations, are being migrated to Asynchronous JavaScript (AJAX). Web development is considerably simplified by the introduction of a framework based on JQuery and Twitter Bootstrap. Finally, the AMI services are being migrated to an OpenStack cloud infrastructure.

  2. Voltage Harmonics Monitoring in a Microgrid Based on Advanced Metering Infrastructure (AMI)

    DEFF Research Database (Denmark)

    Firoozabadi, Mehdi Savaghebi; Guan, Yajuan; Quintero, Juan Carlos Vasquez

    2015-01-01

    Smart meters are the main part of Advanced Metering Infrastructure (AMI) and are usually able to provide detailed information on customers’ energy consumptions, voltage variations and interruptions. In addition, these meters are potentially able to provide more information about power quality (PQ......) disturbances. This paper will address the monitoring of voltage harmonics utilizing the features of smart meters and AMI system. To do this, the first step is to select proper indices to quantify the distortion. An important point which should be considered in this regard is the limited processing power...

  3. The NtAMI1 gene functions in cell division of tobacco BY-2 cells in the presence of indole-3-acetamide.

    Science.gov (United States)

    Nemoto, Keiichirou; Hara, Masamitsu; Suzuki, Masashi; Seki, Hikaru; Muranaka, Toshiya; Mano, Yoshihiro

    2009-01-22

    Tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells can be grown in medium containing indole-3-acetamide (IAM). Based on this finding, the NtAMI1 gene, whose product is functionally equivalent to the AtAMI1 gene of Arabidopsis thaliana and the aux2 gene of Agrobacterium rhizogenes, was isolated from BY-2 cells. Overexpression of the NtAMI1 gene allowed BY-2 cells to proliferate at lower concentrations of IAM, whereas suppression of the NtAMI1 gene by RNA interference (RNAi) caused severe growth inhibition in the medium containing IAM. These results suggest that IAM is incorporated into plant cells and converted to the auxin, indole-3-acetic acid, by NtAMI1.

  4. Migration of the ATLAS Metadata Interface (AMI) to Web 2.0 and cloud

    CERN Document Server

    Odier, Jerome; The ATLAS collaboration; Fulachier, Jerome; Lambert, Fabian

    2015-01-01

    The ATLAS Metadata Interface (AMI) can be considered to be a mature application because it has existed for at least 10 years. Over the last year, we have been adapting the application to some recently available technologies. The web interface, which previously manipulated XML documents using XSL transformations, has been migrated to Asynchronous Java Script (AJAX). Web development has been considerably simplified by the development of a framework for AMI based on JQuery and Twitter Bootstrap. Finally there has been a major upgrade of the python web service client.

  5. Missed Opportunities To Impact Fast Response to AMI Symptoms.

    Science.gov (United States)

    Zapka, Jane G.; Oakes, J. Michael; Simons-Morton, Denise G.; Mann, N. Clay; Goldberg, Robert; Sellers, Deborah E.; Estabrook, Barbara; Gilliland, Janice; Linares, Adriana C.; Benjamin-Garner, Ruby; McGovern, Paul

    2000-01-01

    Examines factors that influence the prompt seeking of care for symptoms of acute myocardial infarction (AMI). Survey of adults in 20 communities in 10 states confirmed the importance of attrition and perceived self-confidence in symptom recognition in care seeking. Concludes that the lack of a significant role of health history and clinician…

  6. PLATFORM DEFORMATION PHASE CORRECTION FOR THE AMiBA-13 COPLANAR INTERFEROMETER

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Umetsu, Keiichi; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China); Proty Wu, Jiun-Huei; Cheng, Tai-An; Fu, Szu-Yuan; Wang, Fu-Cheng [Department of Physics, Institute of Astrophysics, and Center for Theoretical Sciences, National Taiwan University, Taipei 10617, Taiwan (China); Liu, Guo-Chin [Department of Physics, Tamkang University, 251-37 Tamsui, New Taipei City, Taiwan (China); Molnar, Sandor M. [Leung Center for Cosmology and Particle Astrophysics, National Taiwan University, Taipei 10617, Taiwan (China); Chang, Yu-Yen, E-mail: ywliao@asiaa.sinica.edu.tw, E-mail: jhpw@phys.ntu.edu.tw [Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)

    2013-05-20

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  7. PLATFORM DEFORMATION PHASE CORRECTION FOR THE AMiBA-13 COPLANAR INTERFEROMETER

    International Nuclear Information System (INIS)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Umetsu, Keiichi; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter; Proty Wu, Jiun-Huei; Cheng, Tai-An; Fu, Szu-Yuan; Wang, Fu-Cheng; Liu, Guo-Chin; Molnar, Sandor M.; Chang, Yu-Yen

    2013-01-01

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  8. Platform Deformation Phase Correction for the AMiBA-13 Coplanar Interferometer

    Science.gov (United States)

    Liao, Yu-Wei; Lin, Kai-Yang; Huang, Yau-De; Proty Wu, Jiun-Huei; Ho, Paul T. P.; Chen, Ming-Tang; Locutus Huang, Chih-Wei; Koch, Patrick M.; Nishioka, Hiroaki; Cheng, Tai-An; Fu, Szu-Yuan; Liu, Guo-Chin; Molnar, Sandor M.; Umetsu, Keiichi; Wang, Fu-Cheng; Chang, Yu-Yen; Han, Chih-Chiang; Li, Chao-Te; Martin-Cocher, Pierre; Oshiro, Peter

    2013-05-01

    We present a new way to solve the platform deformation problem of coplanar interferometers. The platform of a coplanar interferometer can be deformed due to driving forces and gravity. A deformed platform will induce extra components into the geometric delay of each baseline and change the phases of observed visibilities. The reconstructed images will also be diluted due to the errors of the phases. The platform deformations of The Yuan-Tseh Lee Array for Microwave Background Anisotropy (AMiBA) were modeled based on photogrammetry data with about 20 mount pointing positions. We then used the differential optical pointing error between two optical telescopes to fit the model parameters in the entire horizontal coordinate space. With the platform deformation model, we can predict the errors of the geometric phase delays due to platform deformation with a given azimuth and elevation of the targets and calibrators. After correcting the phases of the radio point sources in the AMiBA interferometric data, we recover 50%-70% flux loss due to phase errors. This allows us to restore more than 90% of a source flux. The method outlined in this work is not only applicable to the correction of deformation for other coplanar telescopes but also to single-dish telescopes with deformation problems. This work also forms the basis of the upcoming science results of AMiBA-13.

  9. Antimicrobial activity against Porphyromonas gingivalis and mechanism of action of the cationic octadecapeptide AmyI-1-18 and its amino acid-substituted analogs.

    Science.gov (United States)

    Taniguchi, Masayuki; Ochiai, Akihito; Takahashi, Kiyoshi; Nakamichi, Shun-Ichi; Nomoto, Takafumi; Saitoh, Eiichi; Kato, Tetsuo; Tanaka, Takaaki

    2016-12-01

    The antimicrobial peptide AmyI-1-18 is a cationic α-helical octadecapeptide derived from α-amylase in rice (Oryza sativa L. japonica) that contains four cationic amino acid residues (two arginines and two lysines). To enhance the antibacterial activity of AmyI-1-18 against Porphyromonas gingivalis (a bacterium associated with periodontal disease), we synthesized 12 analogs bearing substitutions with alanine, leucine, and/or arginine that were designed based on helical wheel projections and investigated their antibacterial properties. The antibacterial properties of four analogs bearing substitution of a single arginine or lysine with alanine were almost similar to those of AmyI-1-18, suggesting that the antibacterial properties depend on the presence of three cationic amino acid residues. Of three single arginine-substituted analogs, AmyI-1-18(G12R) exhibited an antibacterial activity 2.8-fold higher [50% growth-inhibitory concentration (IC 50 ): 4.6 μM] than that of AmyI-1-18 (IC 50 : 13 μM). Likewise, the antibacterial properties of two single leucine-substituted analogs were significantly enhanced; in particular, AmyI-1-18(N3L) exhibited an antibacterial activity (IC 50 : 2.5 μM) 5.2-fold higher than that of AmyI-1-18. The hemolytic activity of AmyI-1-18(N3L) against mammalian red blood cells was low (2% at 50 μM). A membrane-depolarization assay using a membrane potential-sensitive fluorescent dye revealed that, similar to AmyI-1-18, the antibacterial activity of AmyI-1-18(N3L) was not dependent on its membrane-disrupting activity. Our results demonstrate that the antibacterial properties of AmyI-1-18 against P. gingivalis are significantly improved, without a significant increase in hemolytic activity, by replacing asparagine with leucine at position 3. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. AmiD Is a Novel Peptidoglycan Amidase in Wolbachia Endosymbionts of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Miriam Wilmes

    2017-08-01

    Full Text Available Wolbachia endobacteria are obligate intracellular bacteria with a highly reduced genome infecting many arthropod and filarial species, in which they manipulate arthropod reproduction to increase their transmission and are essential for nematode development and survival. The Wolbachia genome encodes all enzymes required for the synthesis of the cell wall building block lipid II, although a peptidoglycan-like structure has not been detected. Despite the ability to synthesize lipid II, Wolbachia from arthropods and nematodes have only a subset of genes encoding enzymes involved in the periplasmic processing of lipid II and peptidoglycan recycling, with arthropods having two more than nematodes. We functionally analyzed the activity of the putative cell wall hydrolase AmiD from the Wolbachia endosymbiont of Drosophila melanogaster, an enzyme not encoded by the nematode endobacteria. Wolbachia AmiD has Zn2+-dependent amidase activity and cleaves intact peptidoglycan, monomeric lipid II and anhydromuropeptides, substrates that are generated during bacterial growth. AmiD may have been maintained in arthropod Wolbachia to avoid host immune recognition by degrading cell wall fragments in the periplasm. This is the first description of a wolbachial lipid II processing enzyme putatively expressed in the periplasm.

  11. Audio-Visual Processing in Meetings: Seven Questions and Current AMI Answers

    NARCIS (Netherlands)

    Al-Hamas, Marc; Hain, Thomas; Cernocky, Jan; Schreiber, Sascha; Poel, Mannes; Rienks, R.J.

    2007-01-01

    The project Augmented Multi-party Interaction (AMI) is concerned with the development of meeting browsers and remote meeting assistants for instrumented meeting rooms – and the required component technologies R&D themes: group dynamics, audio, visual, and multimodal processing, content abstraction,

  12. No gender differences in prognosis and preventive treatment in patients with AMI without significant stenoses

    DEFF Research Database (Denmark)

    Hansen, Kim; Hvelplund, Anders; Abildstrøm, Steen Zabell

    2011-01-01

    : By compiling data from Danish registries, we identified 20,800 patients hospitalized with AMI during 2005-2007. We included the 834 women and 761 men without significant stenoses on CAG who were discharged and alive after 60 days. Main outcome measures: All-cause mortality, recurrent AMI, and redeeming...... a prescription for a lipid-lowering drug, beta-blocker, clopidogrel, or aspirin within 60 days of discharge. Results: During follow-up, 97 women and 60 men died, resulting in a crude female/male hazard ratio (HR) of 1.51 (95% CI 1.09-2.08). After adjustment for age, time-period, and comorbidity, the gender...... difference was attenuated (HR 1.22, 95% CI 0.86-1.72). AMI recurrence was experienced by 28 women and 29 men with a female/male HR 0.88 (95% CI 0.52-1.48). After multivariable adjustment results were similar (HR 0.84, 95% CI 0.50-1.43). More women than men redeemed a prescription for lipid-lowering drugs...

  13. Science goals and expected results from the smart-1 amie multi-coulour micro-camera

    Science.gov (United States)

    Josset, J.-L.; AMIE Team

    2003-04-01

    The Advanced Moon micro-Imager Experiment (AMIE), which will be on board ESA SMART-1, the first European mission to the Moon (launch foreseen in 2003), is an imaging system with scientific, technical and public outreach oriented objectives. The science objectives are to image the Lunar South Pole (Aitken basin), permanent shadow areas (ice deposit), eternal light (crater rims), ancient Lunar Nonmare volcanism, local spectro-photometry and physical state of the lunar surface, and to map high latitudes regions (south) mainly at far side. The main science goals and the expected results from the AMIE multi-colour micro-camera are presented.

  14. Enabling cell-cell communication via nanopore formation: structure, function and localization of the unique cell wall amidase AmiC2 of Nostoc punctiforme.

    Science.gov (United States)

    Büttner, Felix M; Faulhaber, Katharina; Forchhammer, Karl; Maldener, Iris; Stehle, Thilo

    2016-04-01

    To orchestrate a complex life style in changing environments, the filamentous cyanobacterium Nostoc punctiforme facilitates communication between neighboring cells through septal junction complexes. This is achieved by nanopores that perforate the peptidoglycan (PGN) layer and traverse the cell septa. The N-acetylmuramoyl-l-alanine amidase AmiC2 (Npun_F1846; EC 3.5.1.28) in N. punctiforme generates arrays of such nanopores in the septal PGN, in contrast to homologous amidases that mediate daughter cell separation after cell division in unicellular bacteria. Nanopore formation is therefore a novel property of AmiC homologs. Immunofluorescence shows that native AmiC2 localizes to the maturing septum. The high-resolution crystal structure (1.12 Å) of its catalytic domain (AmiC2-cat) differs significantly from known structures of cell splitting and PGN recycling amidases. A wide and shallow binding cavity allows easy access of the substrate to the active site, which harbors an essential zinc ion. AmiC2-cat exhibits strong hydrolytic activity in vitro. A single point mutation of a conserved glutamate near the zinc ion results in total loss of activity, whereas zinc removal leads to instability of AmiC2-cat. An inhibitory α-helix, as found in the Escherichia coli AmiC(E. coli) structure, is absent. Taken together, our data provide insight into the cell-biological, biochemical and structural properties of an unusual cell wall lytic enzyme that generates nanopores for cell-cell communication in multicellular cyanobacteria. The novel structural features of the catalytic domain and the unique biological function of AmiC2 hint at mechanisms of action and regulation that are distinct from other amidases. The AmiC2-cat structure has been deposited in the Protein Data Bank under accession number 5EMI. © 2016 Federation of European Biochemical Societies.

  15. eAMI: A Qualitative Quantification of Periodic Breathing Based on Amplitude of Oscillations

    Science.gov (United States)

    Fernandez Tellez, Helio; Pattyn, Nathalie; Mairesse, Olivier; Dolenc-Groselj, Leja; Eiken, Ola; Mekjavic, Igor B.; Migeotte, P. F.; Macdonald-Nethercott, Eoin; Meeusen, Romain; Neyt, Xavier

    2015-01-01

    Study Objectives: Periodic breathing is sleep disordered breathing characterized by instability in the respiratory pattern that exhibits an oscillatory behavior. Periodic breathing is associated with increased mortality, and it is observed in a variety of situations, such as acute hypoxia, chronic heart failure, and damage to respiratory centers. The standard quantification for the diagnosis of sleep related breathing disorders is the apnea-hypopnea index (AHI), which measures the proportion of apneic/hypopneic events during polysomnography. Determining the AHI is labor-intensive and requires the simultaneous recording of airflow and oxygen saturation. In this paper, we propose an automated, simple, and novel methodology for the detection and qualification of periodic breathing: the estimated amplitude modulation index (eAMI). Patients or Participants: Antarctic cohort (3,800 meters): 13 normal individuals. Clinical cohort: 39 different patients suffering from diverse sleep-related pathologies. Measurements and Results: When tested in a population with high levels of periodic breathing (Antarctic cohort), eAMI was closely correlated with AHI (r = 0.95, P Dolenc-Groselj L, Eiken O, Mekjavic IB, Migeotte PF, Macdonald-Nethercott E, Meeusen R, Neyt X. eAMI: a qualitative quantification of periodic breathing based on amplitude of oscillations. SLEEP 2015;38(3):381–389. PMID:25581914

  16. AToMS: A Ubiquitous Teleconsultation System for Supporting AMI Patients with Prehospital Thrombolysis

    Directory of Open Access Journals (Sweden)

    Bruno S. P. M. Correa

    2011-01-01

    Full Text Available The latest population-based studies in the medical literature worldwide indicate that acute myocardial infarction (AMI patients still experience prolonged delay to be rescued, which often results in morbidity and mortality. This paper reports from a technological standpoint a teleconsultation and monitoring system named AToMS. This system addresses the problem of prehospital delivery of thrombolysis to AMI patients by enabling the remote interaction of the paramedics and a cardiologist available at a Coronary Care Unit (CCU. Such interaction allows the diagnosis of the patient eligibility to the immediate application of thrombolysis, which is meant to reduce the delay between the onset of symptoms and the eventual application of proper treatment. Such delay reduction is meant to increase the AMI patient's chances of survival and decrease the risks of postinfarction sequels. The teleconsultation is held with the support of wireless and mobile technologies, which also allows the cardiologist to monitor the patient while he/she is being taken to the nearest CCU. All exchanged messages among paramedics and cardiologists are recorded to render an auditable system. AToMS has been deployed in a first stage in the city of Rio de Janeiro, where the medical team involved in the project has conducted commissioned tests.

  17. The AMY experiment: Microwave emission from air shower plasmas

    Directory of Open Access Journals (Sweden)

    Alvarez-Muñiz J.

    2016-01-01

    Full Text Available You The Air Microwave Yield (AMY experiment investigate the molecular bremsstrahlung radiation emitted in the GHz frequency range from an electron beam induced air-shower. The measurements have been performed at the Beam Test Facility (BTF of Frascati INFN National Laboratories with a 510 MeV electron beam in a wide frequency range between 1 and 20 GHz. We present the apparatus and the results of the tests performed.

  18. Using AMIE data to study cloud processes within the Madden-Julian Oscillation

    Energy Technology Data Exchange (ETDEWEB)

    Houze, Robert A. [Univ. of Washington, Seattle, WA (United States). Dept. of Atmospheric Sciences

    2015-12-17

    This study uses AMIE data to show how the small clouds in the Madden-Julian Oscillation first organize into lines and other patterns, how they develop the first rainshowers, how those showers deposit cool air over the ocean surface, how this cool air spreads and triggers deeper convection, how the deep convection develops into mesoscale systems, how the mesoscale systems modify the heating profile through the depth of the troposphere, and how the development of the clouds responds to and interacts with large-scale waves circumnavigating the globe at upper levels, and how equatorial trapped waves at lower levels modulates the development of the cloud population. The techniques used to analyze the radar and sounding data collected in AMIE to achieve the above results are innovative, and to obtain more general results we have used regional modeling with a variety of cloud microphysical schemes in combination with the data analyses.

  19. Test Review: An Interview with Amy Gabel--About the WISC-V

    Science.gov (United States)

    Greathouse, Dan; Shaughnessy, Michael F.

    2016-01-01

    Whenever a major intelligence or achievement test is revised, there is always renewed interest in the underlying structure of the test as well as a renewed interest in the scoring, administration, and interpretation changes. In this interview, Amy Gabel discusses the most recent revision of the "Wechsler Intelligence Scale for Children-Fifth…

  20. A broader role for AmyR in Aspergillus niger: regulation of the utilisation of D-glucose or D-galactose containing oligo- and polysaccharides.

    Science.gov (United States)

    vanKuyk, Patricia A; Benen, Jaques A E; Wösten, Han A B; Visser, Jaap; de Vries, Ronald P

    2012-01-01

    AmyR is commonly considered a regulator of starch degradation whose activity is induced by the presence of maltose, the disaccharide building block of starch. In this study, we demonstrate that the role of AmyR extends beyond starch degradation. Enzyme activity assays, genes expression analysis and growth profiling on D-glucose- and D-galactose-containing oligo- and polysaccharides showed that AmyR regulates the expression of some of the Aspergillus niger genes encoding α- and β-glucosidases, α- and β- galactosidases, as well as genes encoding α-amlyases and glucoamylases. In addition, we provide evidence that D-glucose or a metabolic product thereof may be the inducer of the AmyR system in A. niger and not maltose, as is commonly assumed.

  1. Evolution in Cloud Population Statistics of the MJO: From AMIE Field Observations to Global Cloud-Permiting Models

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chidong [Univ. of Miami, Coral Gables, FL (United States)

    2016-08-14

    Motivated by the success of the AMIE/DYNAMO field campaign, which collected unprecedented observations of cloud and precipitation from the tropical Indian Ocean in Octber 2011 – March 2012, this project explored how such observations can be applied to assist the development of global cloud-permitting models through evaluating and correcting model biases in cloud statistics. The main accomplishment of this project were made in four categories: generating observational products for model evaluation, using AMIE/DYNAMO observations to validate global model simulations, using AMIE/DYNAMO observations in numerical studies of cloud-permitting models, and providing leadership in the field. Results from this project provide valuable information for building a seamless bridge between DOE ASR program’s component on process level understanding of cloud processes in the tropics and RGCM focus on global variability and regional extremes. In particular, experience gained from this project would be directly applicable to evaluation and improvements of ACME, especially as it transitions to a non-hydrostatic variable resolution model.

  2. Enhanced ID-Based Authentication Scheme Using OTP in Smart Grid AMI Environment

    Directory of Open Access Journals (Sweden)

    Sang-Soo Yeo

    2014-01-01

    Full Text Available This paper presents the vulnerabilities analyses of KL scheme which is an ID-based authentication scheme for AMI network attached SCADA in smart grid and proposes a security-enhanced authentication scheme which satisfies forward secrecy as well as security requirements introduced in KL scheme and also other existing schemes. The proposed scheme uses MDMS which is the supervising system located in an electrical company as a time-synchronizing server in order to synchronize smart devices at home and conducts authentication between smart meter and smart devices using a new secret value generated by an OTP generator every session. The proposed scheme has forward secrecy, so it increases overall security, but its communication and computation overhead reduce its performance slightly, comparing the existing schemes. Nonetheless, hardware specification and communication bandwidth of smart devices will have better conditions continuously, so the proposed scheme would be a good choice for secure AMI environment.

  3. LES AMIS D'ESCOFFIER AND THE POST-DEPRESSION LABOR MARKET FOR CHEFS DE CUISINE IN AMERICA

    Directory of Open Access Journals (Sweden)

    Martin T. Ollif

    2001-01-01

    Full Text Available This essay uses a cultural studies approach to analyze the effort of the gourmet society Les Amis d'Escoffier to re-create the niche market for chefs’ services in the waning years of the Great Depression. It examines the depressed labor market for chefs after 1912 as well as aspects of the chefs’ culture that informed the unusual rules and rituals Les Amis used to educate wealthy men in gourmandaise. It concludes that, regardless of how successful the society was in its original goal, culture as well as functional response shaped the chefs’ remedy to their labor market problems.

  4. «Il nastro a rovescio». Possibili influenze di Storie Naturali ne La freccia del tempo di Martin Amis

    Directory of Open Access Journals (Sweden)

    Giuseppe Alvino

    2016-11-01

    Full Text Available Il presente contributo si propone di ripercorrere le tappe del rapporto letterario tra Martin Amis e Primo Levi, sottolineando l’attenzione dello scrittore inglese nei confronti dei testi di Levi. Come Amis stesso scrive più volte, Levi fu per lui una delle letture fondamentali nel suo percorso di ricerca letteraria; e nella Postfazione di una delle sue opere principali, Time’s arrow (La freccia del tempo, l’autore richiama per ben due volte l’attenzione su Levi, da un lato, ritenendo che senza le letture leviane non avrebbe potuto scrivere il suo romanzo, e dall’altro, avvertendo il lettore che il titolo pensato originariamente era un’espressione leviana, La natura dell’offesa (oggi secondo titolo de La freccia del tempo. Partendo da questi presupposti si nota come, nel racconto Trattamento di quiescenza della raccolta Storie Naturali, Levi parla tangenzialmente di uno scorrere del tempo al contrario e con una causalità inversa, nello stesso modo in cui Amis, in maniera più sistematica e precisa, costruisce per intero il suo romanzo. Dunque si potrebbe ipotizzare che Amis si sia ispirato non solo al Levi di Se questo è un uomo, La tregua e I sommersi e i salvati per il tema del suo romanzo (e cioè la barbarie nazista, ma anche al Levi dei racconti per il modo tutto particolare di narrare la sua storia. Del resto, la scelta di scrivere il romanzo ‘al contrario’ è funzionale al tema: solo in un mondo con un tempo e una causalità ‘al contrario’ la barbarie dei campi di concentramento sarebbe giustificabile. The purpose of this paper is to explore the literary relationship between Martin Amis and Primo Levi, highlighting how the English writer directed his attention to Levi’s works. As Amis himself often writes, Levi was one of his fundamental readings in his literary research; in the Afterword of one of his masterpieces, Time’s Arrow, the author mentions Levi twice: on the one hand, he claims that he could not

  5. Amy Tan, Author of "The Joy Luck Club." (People to Know).

    Science.gov (United States)

    Kramer, Barbara

    This book, aimed at the young reader, explores the life and career of the Chinese-American author, Amy Tan. It follows her childhood in Oakland, California, through her struggle to accept her Chinese heritage, through her education and marriage to a non-Chinese man, to her early work as a business writer, and finally to her great success as a…

  6. Evolution of the ATLAS Metadata Interface (AMI)

    CERN Document Server

    Odier, Jerome; The ATLAS collaboration; Fulachier, Jerome; Lambert, Fabian

    2015-01-01

    The ATLAS Metadata Interface (AMI) can be considered to be a mature application because it has existed for at least 10 years. Over the years, the number of users and the number of functions provided for these users has increased. It has been necessary to adapt the hardware infrastructure in a seamless way so that the Quality of Service remains high. We will describe the evolution of the application from the initial one, using single server with a MySQL backend database, to the current state, where we use a cluster of Virtual Machines on the French Tier 1 Cloud at Lyon, an ORACLE database backend also at Lyon, with replication to CERN using ORACLE streams behind a back-up server.

  7. Advances in Autonomous Mini Robots : Proceedings of the 6-th AMiRE Symposium

    CERN Document Server

    Joaquin, Sitte; Felix, Werner

    2012-01-01

    Autonomous robots must carry out useful tasks all by themselves relying entirely on their own perceptions of their environment. The cognitive abilities required for autonomous action are largely independent of robot size, which makes mini robots attractive as artefacts for research, education and entertainment. Autonomous mini robots must be small enough for experimentation on a desktop or a small laboratory.  They must be easy to carry and safe for interaction with humans. They must not be expensive. Mini robot designers have to work at the leading edge of technology so that their creations can carry out purposeful autonomic action under these constraints. Since 2001 researchers have met every two years for an international symposium to report on the advances achieved in Autonomous Mini  Robots for Research and Edutainment (AMiRE). The AMiRE Symposium is a single track conference that offers ample opportunities for discussion and exchange of ideas. This volume contains the contributed papers of the 2011 AM...

  8. The amyR-deletion strain of Aspergillus niger CICC2462 is a suitable host strain to express secreted protein with a low background.

    Science.gov (United States)

    Zhang, Hui; Wang, Shuang; Zhang, Xiang Xiang; Ji, Wei; Song, Fuping; Zhao, Yue; Li, Jie

    2016-04-28

    The filamentous fungus Aspergillus niger is widely exploited as an important expression host for industrial production. The glucoamylase high-producing strain A. niger CICC2462 has been used as a host strain for the establishment of a secretion expression system. It expresses recombinant xylanase, mannase and asparaginase at a high level, but some high secretory background proteins in these recombinant strains still remain, such as alpha-amylase and alpha-glucosidase; lead to a low-purity of fermentation products. The aim was to construct an A. niger host strain with a low background of protein secretion. The transcription factor amyR was deleted in A. niger CICC2462, and the results from enzyme activity assays and SDS-PAGE analysis showed that the glucoamylase and amylase activities of the ∆amyR strains were significantly lower than those of the wild-type strain. High-throughput RNA-sequencing and shotgun LC-MS/MS proteomic technology analysis demonstrated that the expression of amylolytic enzymes was decreased at both the transcriptional and translational levels in the ∆amyR strain. Interestingly, the ∆amyR strain growth rate better than the wild-type strain. Our findings clearly indicated that the ∆amyR strain of A. niger CICC2462 can be used as a host strain with a low background of protein secretion.

  9. A starch-binding domain identified in α-amylase (AmyP) represents a new family of carbohydrate-binding modules that contribute to enzymatic hydrolysis of soluble starch.

    Science.gov (United States)

    Peng, Hui; Zheng, Yunyun; Chen, Maojiao; Wang, Ying; Xiao, Yazhong; Gao, Yi

    2014-04-02

    A novel starch-binding domain (SBD) that represents a new carbohydrate-binding module family (CBM69) was identified in the α-amylase (AmyP) of the recently established alpha-amylase subfamily GH13_37. The SBD and its homologues come mostly from marine bacteria, and phylogenetic analysis indicates that they are closely related to the CBM20 and CBM48 families. The SBD exhibited a binding preference toward raw rice starch, but the truncated mutant (AmyPΔSBD) still retained similar substrate preference. Kinetic analyses revealed that the SBD plays an important role in soluble starch hydrolysis because different catalytic efficiencies have been observed in AmyP and the AmyPΔSBD. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  10. Towards Efficient Energy Management: Defining HEMS, AMI and Smart Grid Objectives

    DEFF Research Database (Denmark)

    Rossello Busquet, Ana; Kardaras, Georgios; Soler, José

    2011-01-01

    electricity in the grid will also help to reduce the increase of energy consumption in the future. In order to reduce energy consumption in home environments, researches have been designing Home Energy Management Systems (HEMS). In addition, Advanced Metering Infrastructure (AMI) and smart grids are also...... being developed to distribute and produce electricity efficiently. This paper presents the high level goals and requirements of HEMS. Additionally, it gives an overview of Advanced Metering Infrastructure benefits and smart grids objectives....

  11. AMI: Augmented Michelson Interferometer

    Science.gov (United States)

    Furió, David; Hachet, Martin; Guillet, Jean-Paul; Bousquet, Bruno; Fleck, Stéphanie; Reuter, Patrick; Canioni, Lionel

    2015-10-01

    Experiments in optics are essential for learning and understanding physical phenomena. The problem with these experiments is that they are generally time consuming for both their construction and their maintenance, potentially dangerous through the use of laser sources, and often expensive due to high technology optical components. We propose to simulate such experiments by way of hybrid systems that exploit both spatial augmented reality and tangible interaction. In particular, we focus on one of the most popular optical experiments: the Michelson interferometer. In our approach, we target a highly interactive system where students are able to interact in real time with the Augmented Michelson Interferometer (AMI) to observe, test hypotheses and then to enhance their comprehension. Compared to a fully digital simulation, we are investigating an approach that benefits from both physical and virtual elements, and where the students experiment by manipulating 3D-printed physical replicas of optical components (e.g. lenses and mirrors). Our objective is twofold. First, we want to ensure that the students will learn with our simulator the same concepts and skills that they learn with traditional methods. Second, we hypothesis that such a system opens new opportunities to teach optics in a way that was not possible before, by manipulating concepts beyond the limits of observable physical phenomena. To reach this goal, we have built a complementary team composed of experts in the field of optics, human-computer interaction, computer graphics, sensors and actuators, and education science.

  12. CFRP platform and hexapod mount for the Array of MIcrowave Background Anisotropy (AMiBA)

    Science.gov (United States)

    Raffin, Philippe A.; Martin, Robert N.; Huang, Yau-De; Patt, Ferdinand; Romeo, Robert C.; Chen, Ming-Tang; Kingsley, Jeffrey S.

    2004-09-01

    AMiBA consists of a 90 GHz interferometric array telescope with dishes ranging in size from 0.3 to 2.4 meter in diameter, mounted on a 6-meter fully steerable platform. The dishes are attached to the receivers, which are mounted on a platform controlled by a six degree of freedom hexapod mount. The hexapod mount is a parallel connection manipulator also called Stewart Platform. The basic reference for this mechanism is a paper by Stewart. The Stewart Platform is a unique kinematically constrained work platform. It can be manipulated through the six degrees of freedom. The hexapod also provides better accuracy, rigidity, load to weight ratio and load distribution than a serial manipulator or traditional manipulator. The advantages of the hexapod shows that it is a great choice for the AMiBA project. Vertex Antennentechnik GmbH fabricates the hexapod. Testing has started in Germany. The telescope will be delivered in the summer of 2004. The 6m in diameter hexagonal platform is made of carbon fiber reinforced plastics (CFRP) and consists of seven pieces of three different unique types. The platform can be disassembled and fits in a container for transportation. The mounting plane flatness is an important issue for the platform assembly. The deflection angle of the mounting plane relative to any other mounting position must be less than 20 arcsec. Meanwhile, the platform must endure a loading of 3 tons. The platform has been built by Composite Mirror Applications, Inc. (CMA) in Tucson, and mounted on the Hexapod in Germany. This report describes the design and testing of platform and mount for the AMiBA telescope.

  13. Selection, calibration and mosaicing of AMIE images to build a Moon Atlas as seen by SMART-1

    Science.gov (United States)

    Almeida, M.; Fonseca, J. M.; Grieger, B.; Costa, M.; Mora, A.

    2014-04-01

    In mid 2010 the European Space Agency opened the SMART-1 data to general public. The free access to these data opened new possibilities for its exploitation and use. In this dataset, there are data from the three instruments carried on-board: an ultracompact electronic camera to survey the lunar terrain in visible and near-infrared light (AMIE), an infrared spectrometer to analyze the Moon's minerals (SIR) and an X-ray spectrometer to identify key chemical elements in the lunar surface (D-CIXS). This work is focused on the AMIE captured images, that are used to produce a complete high-resolution atlas of the Moon. During the SMART-1 mission from 2004 to 2006, the onboard AMIE camera collected 31947 start-of-the-art (at the time) resolution and coverage images from lunar surface. However, a considerable number of images were contaminated with noise or suffered from transmission errors, being unusable for any purposes. Also, during the Earth escape phase the radiation damaged significantly the AMIE sensor invalidating the laboratorial flat field correction algorithm. This malfunction was compensated by a new calibration procedure based on in-flight images and theoretical models that will be presented on this paper. After flat field compensated, all images were also calibrated to compensate the sensor color filters at 750, 915 and 960 nm, designed for multi-spectral analysis, although now we use them as full-frame gray scale images. The resulting 1024x1024 images were geographically referenced using the in-board data and mosaiced considering illumination angle and image quality, in order to produce 88 lunar surface maps with lower resolution on the North Lunar pole (spacecraft apolune altitude of 3000Km) and higher resolution on the South Lunar pole (perilune altitude of 27Km). The final maps achieved a coverture of approximately 96% of the Lunar surface. For the latitudes higher than 60ºN and lower than 75ºS polar projection was used with a resolution of 300m

  14. The Demographics of Travel in the Two Rivers-Ottauquechee Region

    Science.gov (United States)

    2009-02-19

    In March of 2008, the Two Rivers-Ottauquechee Regional Commission (TRORC) contracted with TranSystems, a consulting firm based in Montpelier, to conduct a regional transportation planning study for the region. Called the Demographics of Transportatio...

  15. VerSAMI: Versatile and Scalable key management for Smart Grid AMI systems

    OpenAIRE

    Benmalek , Mourad; Challal , Yacine; Derhab , Abdelouahid; Bouabdallah , Abdelmadjid

    2018-01-01

    International audience; In this paper, we propose four new key management schemes for Advanced Metering Infrastructure (AMI) to secure data communications in the Smart Grid (SG). The schemes are based on individual and batch rekeying operations using a novel multi-group key graph structure, are also versatile in the sense that they can support broadcast, unicast, as well as multicast communications. Security analysis shows that our schemes satisfy key management security properties. Furthermo...

  16. Ontological Representation of Light Wave Camera Data to Support Vision-Based AmI

    Directory of Open Access Journals (Sweden)

    José Manuel Molina

    2012-09-01

    Full Text Available Recent advances in technologies for capturing video data have opened a vast amount of new application areas in visual sensor networks. Among them, the incorporation of light wave cameras on Ambient Intelligence (AmI environments provides more accurate tracking capabilities for activity recognition. Although the performance of tracking algorithms has quickly improved, symbolic models used to represent the resulting knowledge have not yet been adapted to smart environments. This lack of representation does not allow to take advantage of the semantic quality of the information provided by new sensors. This paper advocates for the introduction of a part-based representational level in cognitive-based systems in order to accurately represent the novel sensors’ knowledge. The paper also reviews the theoretical and practical issues in part-whole relationships proposing a specific taxonomy for computer vision approaches. General part-based patterns for human body and transitive part-based representation and inference are incorporated to an ontology-based previous framework to enhance scene interpretation in the area of video-based AmI. The advantages and new features of the model are demonstrated in a Social Signal Processing (SSP application for the elaboration of live market researches.

  17. Cell wall amidase AmiC1 is required for cellular communication and heterocyst development in the cyanobacterium Anabaena PCC 7120 but not for filament integrity.

    Science.gov (United States)

    Berendt, Susanne; Lehner, Josef; Zhang, Yao Vincent; Rasse, Tobias M; Forchhammer, Karl; Maldener, Iris

    2012-10-01

    Filamentous cyanobacteria of the order Nostocales display typical properties of multicellular organisms. In response to nitrogen starvation, some vegetative cells differentiate into heterocysts, where fixation of N(2) takes place. Heterocysts provide a micro-oxic compartment to protect nitrogenase from the oxygen produced by the vegetative cells. Differentiation involves fundamental remodeling of the gram-negative cell wall by deposition of a thick envelope and by formation of a neck-like structure at the contact site to the vegetative cells. Cell wall-hydrolyzing enzymes, like cell wall amidases, are involved in peptidoglycan maturation and turnover in unicellular bacteria. Recently, we showed that mutation of the amidase homologue amiC2 gene in Nostoc punctiforme ATCC 29133 distorts filament morphology and function. Here, we present the functional characterization of two amiC paralogues from Anabaena sp. strain PCC 7120. The amiC1 (alr0092) mutant was not able to differentiate heterocysts or to grow diazotrophically, whereas the amiC2 (alr0093) mutant did not show an altered phenotype under standard growth conditions. In agreement, fluorescence recovery after photobleaching (FRAP) studies showed a lack of cell-cell communication only in the AmiC1 mutant. Green fluorescent protein (GFP)-tagged AmiC1 was able to complement the mutant phenotype to wild-type properties. The protein localized in the septal regions of newly dividing cells and at the neck region of differentiating heterocysts. Upon nitrogen step-down, no mature heterocysts were developed in spite of ongoing heterocyst-specific gene expression. These results show the dependence of heterocyst development on amidase function and highlight a pivotal but so far underestimated cellular process, the remodeling of peptidoglycan, for the biology of filamentous cyanobacteria.

  18. Evolution of the Architecture of the ATLAS Metadata Interface (AMI)

    CERN Document Server

    Odier, Jerome; The ATLAS collaboration; Fulachier, Jerome; Lambert, Fabian

    2015-01-01

    The ATLAS Metadata Interface (AMI) is now a mature application. Over the years, the number of users and the number of provided functions has dramatically increased. It is necessary to adapt the hardware infrastructure in a seamless way so that the quality of service remains high. We describe the evolution from the beginning of the application life, using one server with a MySQL backend database, to the current state in which a cluster of virtual machines on the French Tier 1 cloud at Lyon, an Oracle database also at Lyon, with replication to Oracle at CERN and a back-up server are used.

  19. Low-Flow Water Study for the Missouri River.

    Science.gov (United States)

    2008-08-01

    The (MoDOT) retained TranSystems to identify and review low-flow industry : trends, equipment and strategies used in inland navigation settings throughout the United States and worldwide which : may be transferable to the Missouri River and which cou...

  20. Effect of urokinase thrombolysis on the cardiac function, coagulation, and fibrinolytic system in patients with AMI

    Directory of Open Access Journals (Sweden)

    Zhi-Bin Kuang

    2017-06-01

    Full Text Available Objective: To observe the effect of urokinase thrombolysis on the cardiac function, coagulation, and fibrinolytic system in patients with acute myocardial infarction (AMI. Methods: A total of 39 patients with AMI who were admitted in our hospital from March, 2016 to November, 2016 were included in the study and served as the observation group. The peripheral venous blood before and after thrombolysis was collected. The plasma NTproBNP level, related coagulation factors, and fibrinolysis indicators were detected. The cardiac function before treatment was evaluated. A total of 30 healthy individuals who came for physical examinations were served as the control group for contrastive analysis. Results: The plasma NT-proBNP, Fg, and D-D levels before thrombolysis in the observation group were significantly higher than those in the control group, while PT, APTT, and TT in the observation group were significantly shortened. The plasma NT-proBNP and D-D levels 2-48 h after thrombolysis in the observation group were significantly elevated first and reduced later and reached the peak 4 h after treatment, while PT, APTT, and TT were significantly extended first and shortened later. The plasma Fg level was significantly reduced first and elevated later and reached the minimum 4 h after treatment. During the treatment process, in the observation group, 2 had mucocutaneous hemorrhage, 3 had nasal hemorrhage, and 1 had gingival bleeding, but no gastrointestinal bleeding or cerebral hemorrhage occurred. Conclusions: The thrombolytic therapy can effectively reduce the coagulation activity in patients with AMI, strengthen the fibrinolysis activity, and improve the cardiac function.

  1. 3D MR gel dosimetry with lung equivalent gel

    International Nuclear Information System (INIS)

    Scherer, J.; Solleder, M.; Schiessl, I.; Bogner, L.; Herbst, M.

    1998-01-01

    The MR gel dosimetry is used to verify complex 3D treatment plans. Till now this method served only for dose evaluation in homogeneous phantoms. On the way to build a heterogeneous anthropomorphic gel phantom, a lung equivalent gel with the density 0.4 g/cm 3 was developed. First experiments show a 1.55 times higher dose reponse in the low density gel (LD gel). The comparison of a dose distribution in a gel/LD gel/gel slab phantom with Monte Carlo calculations shows good agreement within 5%. More over the accuray of the measuring device magnetic resonance imager was studied in respect to the now exclusive digital image processing with the software MRD (MR dosimetry). Because of the dimensions of the Fricke gel phantom an artefact correction, based on the data from the unirradiated phantom proved to be essential. (orig.) [de

  2. A Study on Literary Criticism from the Perspective of Ethics——Taking Amy Tan's Works for Example

    Institute of Scientific and Technical Information of China (English)

    Yang Yali; Yang Fan

    2017-01-01

    Amy Tan is a rnaster of describing the ethical relationship between people,and her novels focus particularly on family ethics.After interpretation of the setting of the ethical knots,.the trend of the ethical lines,and the structure of ethics in her novels from the perspective of literary ethics,we find out that every novel has its own characteristics and angle,and they share some commonality too.The analysis of the formation and deconstruction of the ethical knots,the ethical lines and the ethical structure in her novels give us an insight into Amy Tan's ethical philosophy that she wants to convey to readers through her novels,that is,harrnonious relationship will ultimately be built as long as people communicate sincerely,regardless of barriers and contradictions.This is not only the ethical ideas the author wants to convey,but also the ethical orientation of her works.

  3. Transdermal delivery of paeonol using cubic gel and microemulsion gel

    Science.gov (United States)

    Luo, Maofu; Shen, Qi; Chen, Jinjin

    2011-01-01

    Background The aim of this study was to develop new systems for transdermal delivery of paeonol, in particular microemulsion gel and cubic gel formulations. Methods Various microemulsion vehicles were prepared using isopropyl myristate as an oil phase, polyoxyethylated castor oil (Cremophor® EL) as a surfactant, and polyethylene glycol 400 as a cosurfactant. In the optimum microemulsion gel formulation, carbomer 940 was selected as the gel matrix, and consisted of 1% paeonol, 4% isopropyl myristate, 28% Cremophor EL/polyethylene glycol 400 (1:1), and 67% water. The cubic gel was prepared containing 3% paeonol, 30% water, and 67% glyceryl monooleate. Results A skin permeability test using excised rat skins indicated that both the cubic gel and microemulsion gel formulations had higher permeability than did the paeonol solution. An in vivo pharmacokinetic study done in rats showed that the relative bioavailability of the cubic gel and microemulsion gel was enhanced by about 1.51-fold and 1.28-fold, respectively, compared with orally administered paeonol suspension. Conclusion Both the cubic gel and microemulsion gel formulations are promising delivery systems to enhance the skin permeability of paeonol, in particular the cubic gel. PMID:21904450

  4. Post-MI depression and levels of serum IL-6 and CRP in AMI patients

    International Nuclear Information System (INIS)

    Huang Tiejun

    2004-01-01

    Objective: To explore the relationship between the presence and severity of post-MI depression and the increased inflammatory activity, as marked by the serum levels of interleukin-6 (IL-6) and C-reactive protein (CRP) after myocardial infarction. Methods: Serum IL-6 and CRP levels were measured in 58 AMI patients within 36 hours after onset of event. Depression was evaluated by self-reporting standardized questionnaire, using a validated Chinese version of Hospiatla Anxiety and Depression Scale (HADS)-Depression Subscale (7 items) within 7 days. Demographic and medical data including LVEF, NYHA cardiac function grading, atherosclerosis severity shown from angiography as well as cardiac risk factors were recorded. Results: Serum levels of IL-6 and CRP were higher in depressive AMI patients than those in non-depressive ones (0.93 ± 0.64 vs 0.48 ± 0.37 ng/L, P<0.05 and 0.96 ± 0.41 vs 0.47 ± 0.26 mg/dL, P<0.05). Neither levels of IL-6 nor HADS-D scores were found to be correlated to the severity of atherosclerosis shown in angiography. Conclusion: Presence and severity of post-MI depression is associated with increased activity of inflammation in patients after myocardial infarction. (authors)

  5. Progress of the array of microwave background anisotropy (AMiBA)

    Science.gov (United States)

    Raffin, Philippe; Koch, Patrick; Huang, Yau-De; Chang, Chia-Hao; Chang, Joshua; Chen, Ming-Tang; Chen, Ke-Yung; Ho, Paul T. P.; Huang, Chih-Wie; Ibañez Roman, Fabiola; Jiang, Homin; Kesteven, Michael; Lin, Kai-Yang; Liu, Guo-Chin; Nishioka, Hiroaki; Umetsu, Keiichi

    2006-06-01

    The Academia Sinica, Institute for Astronomy and Astrophysics (ASIAA) is installing the AMiBA interferometric array telescope at the Mauna Loa Observatory, Hawaii. The 6-meter carbon fiber fully steerable platform is mounted on the Hexapod Mount. After integration and equipment with dummy weights, the platform has been measured by photogrammetry to verify its behavior predicted by Finite Element Analysis. The Hexapod servo control is now operational and equipment of the platform with the initial 7 60-cm dishes, the correlator and electronics is underway. Pointing has started with the aid of the optical telescope. We present the status of the telescope after the servo and initial pointing tests have been carried out. We also present the results of platform measurements by photogrammetry.

  6. Caracterización bioquímica de AmiJ33, una amilasa de Bacillus amyloliquefaciens aislada de suelos cultivados con caña de azúcar en la región del Papaloapan

    Directory of Open Access Journals (Sweden)

    J. J. Montor-Antonio

    2014-01-01

    Full Text Available La amilasa (E.C. 3.2.1.1 de Bacillus amyloliquefaciens JJC33M (AmiJ33 fue producida por fermentación sumergida. Se probó el efecto de peptona, extracto de levadura, Ca+2 y glicina en la producción de AmiJ33. El extracto de levadura y Ca+2 tuvieron un efecto positivo sobre la síntesis de AmiJ33. La enzima fue recuperada mediante precipitación a saturación al 60% con (NH42SO4. El peso molecular aproximado de la enzima purificada fue de 50 kDa. Así mismo, se evaluó el efecto del pH y la temperatura sobre la actividad enzimática, concluyendo que los valores más altos de actividad se observaron a pH 6.0 y 80°C, respectivamente. En condiciones ligeramente ácidas (pH 4.0 y 5.0, AmiJ33 mantuvo el 72% de su actividad. AmiJ33 fue estable por 3 h a 40°C, y por 30 min a 45 y 50°C, conservando el 88 y 82% de actividad residual. A 60°C, la actividad disminuyó 40%. La actividad de AmiJ33 se incrementó 50.27% con b- mercaptoetanol, no fue inhibida por EDTA y se inhibió totalmente con SDS.

  7. The 3-D Tropical Convective Cloud Spectrum in AMIE Radar Observations and Global Climate Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, Courtney [Texas A & M Univ., College Station, TX (United States). Dept. of Atmospheric Sciences

    2015-08-31

    During the three years of this grant performance, the PI and her research group have made a number of significant contributions towards determining properties of tropical deep convective clouds and how models depict and respond to the heating associated with tropical convective systems. The PI has also been an active ARM/ASR science team member, including playing a significant role in AMIE and GoAmazon2014/5. She served on the DOE ASR radar science steering committee and was a joint chair of the Mesoscale Convective Organization group under the Cloud Life Cycle working group. This grant has funded a number of graduate students, many of them women, and the PI and her group have presented their DOE-supported work at various universities and national meetings. The PI and her group participated in the AMIE (2011-12) and GoAmazon2014/5 (2014-15) DOE field deployments that occurred in the tropical Indian Ocean and Brazilian Amazon, respectively. AMIE observational results (DePasquale et al. 2014, Feng et al. 2014, Ahmed and Schumacher 2015) focus on the variation and possible importance of Kelvin waves in various phases of the Madden-Julian Oscillation (MJO), on the synergy of the different wavelength radars deployed on Addu Atoll, and on the importance of humidity thresholds in the tropics on stratiform rain production. Much of the PIs GoAmazon2014/5 results to date relate to overviews of the observations made during the field campaign (Martin et al. 2015, 2016; Fuentes et al. 2016), but also include the introduction of the descending arm and its link to ozone transport from the mid-troposphere to the surface (Gerken et al. 2016). Vertical motion and mass flux profiles from GoAmazon (Giangrande et al. 2016) also show interesting patterns between seasons and provide targets for model simulations. Results from TWP-ICE (Schumacher et al. 2015), which took place in Darwin, Australia in 2006 show that vertical velocity retrievals from the profilers provide structure to

  8. Health and aging in elderly farmers: the AMI cohort

    Directory of Open Access Journals (Sweden)

    Pérès Karine

    2012-07-01

    Full Text Available Abstract Background The health of the agricultural population has been previously explored, particularly in relation to the farming exposures and among professionally active individuals. However, few studies specifically focused on health and aging among elders retired from agriculture. Yet, this population faces the long-term effects of occupational exposures and multiple difficulties related to living and aging in rural area (limited access to shops, services, and practitioners. However, these difficulties may be counter-balanced by advantages related to healthier lifestyle, richer social support and better living environment. The general aim of the AMI cohort was to study health and aging in elderly farmers living in rural area through a multidisciplinary approach, with a main focus on dementia. Methods/design The study initially included 1 002 participants, randomly selected from the Farmer Health Insurance rolls. Selection criteria were: being 65 years and older; living in rural area in Gironde (South-Western France; being retired from agriculture after at least 20 years of activity and being affiliated to the Health Insurance under own name. The study started in 2007, with two follow-up visits over 5 years. Baseline visits were conducted at home by a neuropsychologist then by a geriatrician for all cases suspected of dementia, Parkinson’s disease and depression (to confirm the diagnosis, and by a nurse for others. A large panel of data were collected through standardised questionnaires: complete neuropsychological assessment, material and social living environment, psychological transition to retirement, lifestyle (smoking, alcohol and diet, medications, disability in daily living, sensory impairments and some clinical measures (blood pressure, depression symptomatology, anxiety, visual test, anthropometry…. A blood sampling was performed with biological measurements and constitution of a biological bank, including DNA. Brain MRI

  9. Clinical significance of measurement of changes of plasma Hcy and ET levels after treatment in patients with acute myocardial infarction (AMI)

    International Nuclear Information System (INIS)

    Zhou Feng

    2008-01-01

    Objective: To explore the clinical significance of changes of plasma Hcy and ET levels in patients with AMI after treatment. Methods: Plasma Hcy and ET levels were measured with RIA in 33 patients with acute myocardial infarction both before and after treatment as well as in 30 controls. Results: Plasma Hcy and ET levels were significantly higher in the AMI patients than those in the controls before treatment and the levels were mutually positively correlated (P 0.05), but plasma ET levels, though dropped markedly remained significantly higher (P<0.05). Conclusion: Changes of plasma Hcy and ET levels after treatment might be of prognostic importance in patients with acute myocardial infarction. (authors)

  10. Sol-Gel Glasses

    Science.gov (United States)

    Mukherjee, S. P.

    1985-01-01

    Multicomponent homogeneous, ultrapure noncrystalline gels/gel derived glasses are promising batch materials for the containerless glass melting experiments in microgravity. Hence, ultrapure, homogeneous gel precursors could be used to: (1) investigate the effect of the container induced nucleation on the glass forming ability of marginally glass forming compositions; and (2) investigate the influence of gravity on the phase separation and coarsening behavior of gel derived glasses in the liquid-liquid immiscibility zone of the nonsilicate systems having a high density phase. The structure and crystallization behavior of gels in the SiO2-GeO2 as a function of gel chemistry and thermal treatment were investigated. As are the chemical principles involved in the distribution of a second network former in silica gel matrix being investigated. The procedures for synthesizing noncrystalline gels/gel-monoliths in the SiO2-GeO2, GeO2-PbO systems were developed. Preliminary investigations on the levitation and thermal treatment of germania silicate gel-monoliths in the Pressure Facility Acoustic Levitator were done.

  11. FTT-MA: A Flexible Time-Triggered Middleware Architecture for Time Sensitive, Resource-Aware AmI Systems

    Directory of Open Access Journals (Sweden)

    Federico Pérez

    2013-05-01

    Full Text Available There is an increasing number of Ambient Intelligence (AmI systems that are time-sensitive and resource-aware. From healthcare to building and even home/office automation, it is now common to find systems combining interactive and sensing multimedia traffic with relatively simple sensors and actuators (door locks, presence detectors, RFIDs, HVAC, information panels, etc.. Many of these are today known as Cyber-Physical Systems (CPS. Quite frequently, these systems must be capable of (1 prioritizing different traffic flows (process data, alarms, non-critical data, etc., (2 synchronizing actions in several distributed devices and, to certain degree, (3 easing resource management (e.g., detecting faulty nodes, managing battery levels, handling overloads, etc.. This work presents FTT-MA, a high-level middleware architecture aimed at easing the design, deployment and operation of such AmI systems. FTT-MA ensures that both functional and non-functional aspects of the applications are met even during reconfiguration stages. The paper also proposes a methodology, together with a design tool, to create this kind of systems. Finally, a sample case study is presented that illustrates the use of the middleware and the methodology proposed in the paper.

  12. FTT-MA: A Flexible Time-Triggered Middleware Architecture for Time Sensitive, Resource-Aware AmI Systems

    Science.gov (United States)

    Noguero, Adrián; Calvo, Isidro; Pérez, Federico; Almeida, Luis

    2013-01-01

    There is an increasing number of Ambient Intelligence (AmI) systems that are time-sensitive and resource-aware. From healthcare to building and even home/office automation, it is now common to find systems combining interactive and sensing multimedia traffic with relatively simple sensors and actuators (door locks, presence detectors, RFIDs, HVAC, information panels, etc.). Many of these are today known as Cyber-Physical Systems (CPS). Quite frequently, these systems must be capable of (1) prioritizing different traffic flows (process data, alarms, non-critical data, etc.), (2) synchronizing actions in several distributed devices and, to certain degree, (3) easing resource management (e.g., detecting faulty nodes, managing battery levels, handling overloads, etc.). This work presents FTT-MA, a high-level middleware architecture aimed at easing the design, deployment and operation of such AmI systems. FTT-MA ensures that both functional and non-functional aspects of the applications are met even during reconfiguration stages. The paper also proposes a methodology, together with a design tool, to create this kind of systems. Finally, a sample case study is presented that illustrates the use of the middleware and the methodology proposed in the paper. PMID:23669711

  13. Participation in the ARGUS experiment at the DORIS Collider at Desy, Hamburg, Germany and participation in the AMY experiment at the TRISTAN Collider in Tsukuba, Japan: 1986 progress report

    International Nuclear Information System (INIS)

    Darden, C.

    1987-01-01

    Progress is reported on the AMY and ARGUS detectors, as well as plans for the next funding period. The AMY detector is reported as well on the way to completion, but not yet ready to take data. The ARGUS detector is reported to have completed its fourth year of operation. Some upsilon 1S decay data are discussed. 37 refs

  14. Lunar photometric modelling with SMART-1/AMIE imaging data

    International Nuclear Information System (INIS)

    Wilkman, O.; Muinonen, K.; Videen, G.; Josset, J.-L.; Souchon, A.

    2014-01-01

    We investigate the light-scattering properties of the lunar mare areas. A large photometric dataset was extracted from images taken by the AMIE camera on board the SMART-1 spacecraft. Inter-particle shadowing effects in the regolith are modelled using ray-tracing simulations, and then a phase function is fit to the data using Bayesian techniques and Markov chain Monte Carlo. Additionally, the data are fit with phase functions computed from radiative-transfer coherent-backscatter (RT-CB) simulations. The results indicate that the lunar photometry, including both the opposition effect and azimuthal effects, can be explained well with a combination of inter-particle shadowing and coherent backscattering. Our results produce loose constraints on the mare physical properties. The RT-CB results indicate that the scattering volume element is optically thick. In both the Bayesian analysis and the RT-CB fit, models with lower packing density and/or higher surface roughness always produce better fits to the data than densely packed, smoother ones

  15. GelTouch

    DEFF Research Database (Denmark)

    Miruchna, Viktor; Walter, Robert; Lindlbauer, David

    2015-01-01

    We present GelTouch, a gel-based layer that can selectively transition between soft and stiff to provide tactile multi-touch feedback. It is flexible, transparent when not activated, and contains no mechanical, electromagnetic, or hydraulic components, resulting in a compact form factor (a 2mm thin...... touchscreen layer for our prototype). The activated areas can be morphed freely and continuously, without being limited to fixed, predefined shapes. GelTouch consists of a poly(N-isopropylacrylamide) gel layer which alters its viscoelasticity when activated by applying heat (>32 C). We present three different...

  16. The gel electrophoresis markup language (GelML) from the Proteomics Standards Initiative.

    Science.gov (United States)

    Gibson, Frank; Hoogland, Christine; Martinez-Bartolomé, Salvador; Medina-Aunon, J Alberto; Albar, Juan Pablo; Babnigg, Gyorgy; Wipat, Anil; Hermjakob, Henning; Almeida, Jonas S; Stanislaus, Romesh; Paton, Norman W; Jones, Andrew R

    2010-09-01

    The Human Proteome Organisation's Proteomics Standards Initiative has developed the GelML (gel electrophoresis markup language) data exchange format for representing gel electrophoresis experiments performed in proteomics investigations. The format closely follows the reporting guidelines for gel electrophoresis, which are part of the Minimum Information About a Proteomics Experiment (MIAPE) set of modules. GelML supports the capture of metadata (such as experimental protocols) and data (such as gel images) resulting from gel electrophoresis so that laboratories can be compliant with the MIAPE Gel Electrophoresis guidelines, while allowing such data sets to be exchanged or downloaded from public repositories. The format is sufficiently flexible to capture data from a broad range of experimental processes, and complements other PSI formats for MS data and the results of protein and peptide identifications to capture entire gel-based proteome workflows. GelML has resulted from the open standardisation process of PSI consisting of both public consultation and anonymous review of the specifications.

  17. Stacking gels: A method for maximising output for pulsed-field gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Heng See

    2009-01-01

    Full Text Available Pulsed field gel electrophoresis (PFGE, the gold standard of molecular typing methods, has a major disadvantage of an unusually long electrophoretic time. From the original protocol of 6 days, it was modified to 3 days and subsequently to a single day. We describe the procedure of stacking five to six gels one on top of another in order to increase and maximize the output in a shorter time without compromising the resolution and reproducibility. All the variables that affect pulsed field gels during electrophoresis were taken into consideration. We firstly optimized the parameters to be used and secondly determined whether stacking of five to six gels had any effect on the molecular separation during electrophoresis in comparison with a single gel run. DNA preparation, restriction, electrophoresis, staining and gel documentation was carried out based on previously published methods. Gels were analysed using BioNumerics and dice coefficient and unweighted pair group methods were used to generate dendrograms based on 1.5% tolerance values. Identical band profiles and band resolution-separation were seen in the PFGE patterns with single gel and multiple stacking gels. Cluster analysis further strengthened the fact that results from stacking gels were reproducible and comparable with a single gel run. This method of stacking gels saves time and maximizes the output at the same time. The run time for a single gel was about 28 hours, but with six stacked gels the run time was 54 hours compared with 28 x 6 = 168 hours if they were run separately as single gels thus saving time of 67.86%. Beside the big factor of saving time, stacking gels save resources (electricity, reagents, water, chemicals and working time by increasing the sample throughput in a shorter time without compromising on quality of data. But optimization of working parameters is vital depending on the PFGE system used.

  18. Electrophoresis of DNA in agarose gels, polyacrylamide gels and in free solution

    Science.gov (United States)

    Stellwagen, Nancy C.

    2009-01-01

    This review describes the electrophoresis of curved and normal DNA molecules in agarose gels, polyacrylamide gels and in free solution. These studies were undertaken to clarify why curved DNA molecules migrate anomalously slowly in polyacrylamide gels but not in agarose gels. Two milestone papers are cited, in which Ferguson plots were used to estimate the effective pore size of agarose and polyacrylamide gels. Subsequent studies on the effect of the electric field on agarose and polyacrylamide gel matrices, DNA interactions with the two gel matrices, and the effect of curvature on the free solution mobility of DNA are also described. The combined results suggest that the anomalously slow mobilities observed for curved DNA molecules in polyacrylamide gels are due primarily to preferential interactions of curved DNAs with the polyacrylamide gel matrix; the restrictive pore size of the matrix is of lesser importance. In free solution, DNA mobilities increase with increasing molecular mass until leveling off at a plateau value of (3.17 ± 0.01) × 10-4 cm2/Vs in 40 mM Tris-acetate-EDTA buffer at 20°C. Curved DNA molecules migrate anomalously slowly in free solution as well as in polyacrylamide gels, explaining why the Ferguson plots of curved and normal DNAs containing the same number of base pairs extrapolate to different mobilities at zero gel concentration. PMID:19517510

  19. Robillard, Amy E. and Ron Fortune (eds. Authorship Contested. Cultural Challenges to the Authentic Autonomous Author (New York, and London: Routledge, 2015

    Directory of Open Access Journals (Sweden)

    Alex Ciorogar

    2016-12-01

    Full Text Available A review of Amy E. Robillard and Ron Fortune's (eds Authorship Contested: Cultural Challenges to the Authentic Autonomous Author. New York, and London: Routledge, 2015. 214 pp. £100.

  20. Transport Phenomena in Gel

    Directory of Open Access Journals (Sweden)

    Masayuki Tokita

    2016-05-01

    Full Text Available Gel becomes an important class of soft materials since it can be seen in a wide variety of the chemical and the biological systems. The unique properties of gel arise from the structure, namely, the three-dimensional polymer network that is swollen by a huge amount of solvent. Despite the small volume fraction of the polymer network, which is usually only a few percent or less, gel shows the typical properties that belong to solids such as the elasticity. Gel is, therefore, regarded as a dilute solid because its elasticity is much smaller than that of typical solids. Because of the diluted structure, small molecules can pass along the open space of the polymer network. In addition to the viscous resistance of gel fluid, however, the substance experiences resistance due to the polymer network of gel during the transport process. It is, therefore, of importance to study the diffusion of the small molecules in gel as well as the flow of gel fluid itself through the polymer network of gel. It may be natural to assume that the effects of the resistance due to the polymer network of gel depends strongly on the network structure. Therefore, detailed study on the transport processes in and through gel may open a new insight into the relationship between the structure and the transport properties of gel. The two typical transport processes in and through gel, that is, the diffusion of small molecules due to the thermal fluctuations and the flow of gel fluid that is caused by the mechanical pressure gradient will be reviewed.

  1. Thorium inorganic gels

    International Nuclear Information System (INIS)

    Genet, M.; Brandel, V.

    1988-01-01

    The optimum pH and concentration values of thorium salts and oxoacids or oxoacid salts which lead to transparent and stable inorganic gels have been determined. The isotherm drying process of the gel at 50 0 C leads successively to a partly dehydrated gel, then, to the formation of an unusual liquid phase and, finally to a dry amorphous solid phase which is still transparent. This kind of transparent inorganic gels and amorphous phase can be used as matrices for spectroscopic studies [fr

  2. Asteroid Moon Micro-imager Experiment (amie) For Smart-1 Mission, Science Objectives and Devel- Opment Status.

    Science.gov (United States)

    Josset, J.-L.; Heather, D.; Dunkin, S.; Roussel, F.; Beauvivre, S.; Kraenhenbuehl, D.; Plancke, P.; Lange-Vin, Y.; Pinet, P.; Chevrel, S.; Cerroni, P.; de Sanctis, M.-C.; Dillelis, A.; Sodnik, Z.; Koschny, D.; Barucci, A.; Hofmann, B.; Josset, M.; Muinonen, K.; Pironnen, J.; Ehrenfreud, P.; Shkuratov, Y.; Shevchenko, V.

    The Asteroid Moon micro-Imager Experiment (AMIE), which will be on board the first ESA SMART-1 mission to the Moon (launch foreseen late 2002), is an imaging sys- tem with scientific, technical and public outreach oriented objectives. The science objectives are to imagine the Lunar South Pole (Aitken basin), permanent shadow areas (ice deposit), eternal light (crater rims), ancient Lunar Non- mare volcanism, local spectro-photometry and physical state of the lunar surface, and to map high latitudes regions (south) mainly at far side (Fig. 1). The technical objectives are to perform a laser-link experiment (detection of laser beam emitted by ESA Tenerife ground station), flight demonstration of new technologies, navigation aid (feasi- bility study), and on-board autonomy investigations. Figure 3: AMIE camera (light source and a photodiode to verify the stability of the incident flux. The optical system is com- posed of a lens to insure good focusing on the samples (focus with the camera is at distance > 100m) and a mirror to image downwards. The samples used were anorthosite from northern Finland, basalt from Antarctis, meteorites and other lunar analog materials. A spectralon panel has also been used to have flat fields references. The samples were imaged with dif- Figure 1: SMART-1 camera imaging the Moon (simulated view) ferent phase angles. Figure 4 shows images obtained with In order to have spectral information of the surface of the basalt and olivine samples, with different integration times Moon, the camera is equipped with a set of filters (Fig. 2), in order to have information in all areas. introduced between the CCD and the teleobjective. Bandpass-filter No Filter, 750 nm (1) AR coating (3) Bandpass-filter 915 nm (2) Longpass-filter 960 nm (4) Band- Band- Figure 4: Basalt and Olivine sample ­ entire image (left) and passfilter passfilter 915 nm 750 nm visible part () (6) (7) Bandpass- More than 150 images were acquired during this validation filter 847

  3. First Results at the Moon from the SMART-1 / AMIE Experiment

    Science.gov (United States)

    Josset, J. L.; Beauvivre, S.; AMIE Team

    2005-08-01

    The Advanced Moon micro-Imager Experiment (AMIE), on board ESA SMART-1, the first European mission to the Moon (launched on 27th September 2003), is an imaging system with scientific, technical and public outreach oriented objectives. The science objectives are to image the Lunar South Pole, permanent shadow areas (ice deposit), eternal light (crater rims), ancient Lunar Non-mare volcanism, local spectro-photometry and physical state of the lunar surface, and to map high latitudes regions (south) mainly at far side (South Pole Aitken basin). The technical objectives are to perform a laserlink experiment (detection of laser beam emitted by ESA/Tenerife ground station), flight demonstration of new technologies and on-board autonomy navigation. The public outreach and educational objectives are to promote planetary exploration. We present here the first results obtained during the cruise phase and at the Moon.

  4. Colloid molecular weight estimation by gel chromatography/acrylamide gel electrophoresis

    International Nuclear Information System (INIS)

    Liberatore, F.A.; Dearborn, C.; Nigam, S.; Poon, C.; Camin, L.; Liteplo, M.

    1984-01-01

    Size or molecular weight (MW) estimation of radiolabeled collides in aqueous solutions has long been a problem. The authors have prepared several minimicroaggregated albumin colloids (mμAA) by heat denaturation of stannous-containing HSA solutions at pH 7.0, 7.5, and 8.5). The resulting colloids were labeled with Tc-99m and compared with Au-198 colloid and Tc-99m-antimony sulfide colloid (Tc-99m-Sb/sub 2/S3) by gel chromatography and gel electrophoresis. Tc-99mm-mμAA aggregated at pH 7.0 and the Au-198 colloid appeared in the external void volume of a BioRad A5.0 agarose column indicating an apparent MW of > 5 x 10/sup 6/ daltons. The pH7.5 Tc-99m-mμAA, migrated within the filtration range of the column as did a small fraction of Tc-99m-Sb/sub 2/S/sub 3/, suggesting that the MW is between 6 x 10/sup 4/ - 5 x 10/sup 6/ daltons. The Tc-99m-mμAA, aggregated at pH 8.5, had an apparent MW on gel filtration similar to that of untreated albumin, MW 6.6 x 10-/sup 4/ daltons. The mobilities of the colloids, on acrylamide disc gel electrophoresis, were consistent with the results on gel chromatography. The largest colloids, Au-198 colloid and pH 7.0 Tc-99m-mμAA, barely entered the separating gel; intermediate sized colloids, a small fraction of Tc-99m-Sb/sub 2/S/sub 3/ and pH 7.5 Tc-99m-mμAA migrated farther into the separating gel; while pH 8.5 Tc-99m-mμAA had mobility approaching that of untreated albumin. Lymphoscintigraphy studies using these colloids in animals showed the predicted, particle size-related differences in migration and clearance. The authors conclude that gel chromatography and gel electrophoresis are useful methods for estimating the apparent size of the colloidal particles

  5. A novel approach for UI charge reduction using AMI based load prioritization in smart grid

    Directory of Open Access Journals (Sweden)

    Avani Pujara

    2017-09-01

    Full Text Available System frequency is vital part for power system balance. As per India Electricity Grid code frequency should be in the range of 49.5 Hz–50.5 Hz. Deviation from above mentioned range is charged as Unscheduled Interchange (UI charge. This paper proposes a new method for load and frequency control based on control of third parameter of three-part Availability Based Tariff (ABT i.e. Unscheduled Interchange charges. New circuit is designed considering prioritization of load and using Advanced Metering Infrastructure (AMI under Smart Grid environment.

  6. Internal structure analysis of particle-double network gels used in a gel organ replica

    Science.gov (United States)

    Abe, Mei; Arai, Masanori; Saito, Azusa; Sakai, Kazuyuki; Kawakami, Masaru; Furukawa, Hidemitsu

    2016-04-01

    In recent years, the fabrication of patient organ replicas using 3D printers has been attracting a great deal of attention in medical fields. However, the cost of these organ replicas is very high as it is necessary to employ very expensive 3D printers and printing materials. Here we present a new gel organ replica, of human kidney, fabricated with a conventional molding technique, using a particle-double network hydrogel (P-DN gel). The replica is transparent and has the feel of a real kidney. It is expected that gel organ replicas produced this way will be a useful tool for the education of trainee surgeons and clinical ultrasonography technologists. In addition to developing a gel organ replica, the internal structure of the P-DN gel used is also discussed. Because the P-DN gel has a complex structure comprised of two different types of network, it has not been possible to investigate them internally in detail. Gels have an inhomogeneous network structure. If it is able to get a more uniform structure, it is considered that this would lead to higher strength in the gel. In the present study we investigate the structure of P-DN gel, using the gel organ replica. We investigated the internal structure of P-DN gel using Scanning Microscopic Light Scattering (SMILS), a non-contacting and non-destructive.

  7. Polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baldock, C [Institute of Medical Physics, School of Physics, University of Sydney (Australia); De Deene, Y [Radiotherapy and Nuclear Medicine, Ghent University Hospital (Belgium); Doran, S [CRUK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Surrey (United Kingdom); Ibbott, G [Radiation Physics, UT M D Anderson Cancer Center, Houston, TX (United States); Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Lepage, M [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et de radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); McAuley, K B [Department of Chemical Engineering, Queen' s University, Kingston, ON (Canada); Oldham, M [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Schreiner, L J [Cancer Centre of South Eastern Ontario, Kingston, ON (Canada)], E-mail: c.baldock@physics.usyd.edu.au, E-mail: yves.dedeene@ugent.be

    2010-03-07

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. (topical review)

  8. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  9. Removing water from gels

    International Nuclear Information System (INIS)

    Lane, E.S.; Winter, J.A.

    1982-01-01

    Water is removed from a gel material by contacting the gel material with an organic liquid and contacting the organic liquid with a gas such that water is taken up by the gas. The invention, in one embodiment, may be used to dry gel materials whilst maintaining an open porous network therein. In one example, the invention is applied to gel precipitated spheres containing uranium and plutonium. (author)

  10. Influência do conteúdo vaginal de gestantes sobre a recuperação do estreptococo do grupo B nos meios de transporte Stuart e Amies Influence of vaginal environment of pregnant women on the recovery of group B streptococcus in Stuart and Amies transport media

    Directory of Open Access Journals (Sweden)

    José Antonio Simões

    2005-11-01

    Full Text Available OBJETIVO: avaliar a influência do meio vaginal de gestantes na sobrevivência do estreptococo do grupo B (EGB mantido por 8, 24 e 48 horas nos meios de transporte Amies e Stuart. MÉTODOS: foram coletados três swabs vaginais de 30 gestantes atendidas no Ambulatório de Pré-Natal do Centro de Atenção Integral à Saúde da Mulher (CAISM, Universidade Estadual de Campinas (UNICAMP. O primeiro swab foi mergulhado diretamente no meio seletivo de Todd-Hewitt; o segundo foi utilizado para a realização da bacterioscopia corada pelo Gram e o terceiro foi mergulhado em 2 mL de solução salina à qual foram acrescentados 200 µL de uma suspensão contendo EGB na concentração de 1-2 x 10(8 unidades formadoras de colônia. Desta última suspensão de EGB, foram colhidos três swabs do meio Amies e três do meio Stuart, os quais foram mantidos em temperatura ambiente por 8, 24 e 48 horas, para posterior semeadura em ágar sangue. A leitura do crescimento das placas foi realizada após 24 horas de incubação e classificada semiquantitativamente (0-3 cruzes de acordo com o número de colônias observadas. A análise estatística foi efetuada com o teste exato de Fisher. RESULTADOS: a recuperação do EGB nos meios de transporte Amies e Stuart após 48 horas de estocagem foi de 97 e 87%, respectivamente. Em um dos quatro casos em que não houve a recuperação do EGB após 48 horas de armazenamento, o pH vaginal foi superior a 4,5 e em dois casos havia a presença de vaginose citolítica. CONCLUSÕES: ambos os meios de transporte mostraram-se adequados para a recuperação do EGB em gestantes até 48 horas após a coleta. As características do meio vaginal não influenciaram a recuperação do EGB no presente estudo.PURPOSE: to evaluate the influence of vaginal environment of pregnant women on group B streptococcus (GBS survival after 8, 24 e 48 h in Amies and Stuart transport media. METHODS: Three vaginal samples were collected from 30 pregnant

  11. Categorization of rheological scaling models for particle gels applied to casein gels

    NARCIS (Netherlands)

    Mellema, M.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    Rennet-induced casein gels made from skim milk were studied rheologically. A scaling model or framework for describing the rheological behavior of gels is discussed and used for classification of the structure of casein gels. There are two main parameters in the model that describe the number of

  12. Layered AMI Architecture for Various Grid Topologies and Communication Technologies

    Directory of Open Access Journals (Sweden)

    I. Petruševski

    2016-06-01

    Full Text Available Advanced metering infrastructure (AMI system, proposed in this paper, is capable of fulfilling all smart metering functionalities in real-time. The novel Local Metering Concentrator (LMC layer is introduced as the set of independent embedded system components, allowing distributed architecture implementation. Two main data flows can be defined as command request processing and meter data acquisition. A command request, initiated by some of the top layer applications, is processed and forwarded through the system to the LMC layer, where the request is executed and the status is sent as a reply. The data and event acquisition is performed as an automatic function of the LMC layer. The collected data is forwarded to the system as soon as it is downloaded from the meters. The results of more than one-year exploitation of the installed pilot system are presented, emphasizing the real-time load profile data acquisition, allowing the distribution system operators (DSO and the end consumer to be actively involved in energy saving. The introduced architecture enables load profiling, energy diagnostic and easy integration with any meter data management system.

  13. Metal-silica sol-gel materials

    Science.gov (United States)

    Stiegman, Albert E. (Inventor)

    2002-01-01

    The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses. The present invention also relates to organopolymer metal-silica sol-gel composites where the pores of the metal-silica sol-gel glasses are filled with an organic polymer polymerized by the sol-gel glass.

  14. Study of nuclear glasses alteration gel and synthesis of some model gels; Etude du gel d`alteration des verres nucleaires et synthese de gels modeles

    Energy Technology Data Exchange (ETDEWEB)

    Ricol, S

    1995-10-05

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs.

  15. Thoria sol-gel processes

    International Nuclear Information System (INIS)

    Matthews, R.B.

    1978-10-01

    Alternate fuel fabrication techniques are being developed at WNRE as part of the thorium fuel cycle program. The sol-gel techniques are attractive and this report assembles and summarizes information relating to thoria sol-gel fuels. Some background information on the behaviour and advantages of sol-gel fuel forms is presented, followed by a review of relevant colloid chemistry and an explanation of the fundamental steps of sol-gel processes. Finally, several variants to the basic process are reviewed and evaluated. (author)

  16. Review of Fricke gel dosimeters

    International Nuclear Information System (INIS)

    Schreiner, L J

    2004-01-01

    The innovation of adding a gel matrix to the traditional Fricke dosimeter to stabilize geometric information established the field of gel dosimetry for radiation therapy. A discussion of Fricke gels provides an overview of the issues that determine the dose response of all gel dosimeters in general. In this paper we review some of the features of Fricke systems to illustrate these issues and, in addition, to motivate renewed clinical interest in Fricke gels

  17. Gel nano-particulates against radioactivity; Des nanoparticules en gel contre la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Deroin, Ph

    2004-11-01

    The Argonne research center (USA) has developed a 'super-gel' compound, a polymer close to those used in baby's diapers, which can reach a 90% efficiency in the radioactive decontamination of porous materials, like bricks or concrete. The contaminated materials are sprayed with a mixture of polymer gel and wetting agent with nano-particulates in suspension. Under the action of the wetting agent, radioactivity migrates from the pores to the gel and is trapped by the nano-particulates. The drying and recycling of the gel allows to reduce the volume of radioactive wastes. Short paper. (J.S.)

  18. Polymer gel dosimeters with enhanced sensitivity for use in x-ray CT polymer gel dosimetry

    International Nuclear Information System (INIS)

    Jirasek, A; Hilts, M; McAuley, K B

    2010-01-01

    A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter formulations with improved dose sensitivity for x-ray CT polymer gel dosimetry. We incorporate an isopropanol co-solvent into an N-isopropylacrylamide-based gel formulation in order to increase the total monomer/crosslinker concentration (%T) within the formulation. It is shown that gels of high %T exhibit enhanced dose sensitivity and dose resolutions over traditional formulations. The gels are shown to be temporally stable and reproducible. A single formulation (16%T) is used to demonstrate the capabilities of the x-ray CT polymer gel dosimetry system in measuring known dose distributions. A 1 L gel volume is exposed to three separate irradiations: a single-field percent depth dose, a two-field 'cross' and a three-field 'test case'. The first two irradiations are used to generate a dose calibration curve by which images are calibrated. The calibrated images are compared with treatment planning predictions and it is shown that the x-ray CT polymer gel dosimetry system is capable of capturing spatial and dose information accurately. The proposed new gel formulation is shown to be sensitive, stable and to improve the dose resolution over current formulations so as to provide a feasible gel for clinical applications of x-ray CT polymer gel dosimetry.

  19. Design of Autonomous Gel Actuators

    Directory of Open Access Journals (Sweden)

    Shuji Hashimoto

    2011-01-01

    Full Text Available In this paper, we introduce autonomous gel actuators driven by chemical energy. The polymer gels prepared here have cyclic chemical reaction networks. With a cyclic reaction, the polymer gels generate periodical motion. The periodic motion of the gel is produced by the chemical energy of the oscillatory Belouzov-Zhabotinsky (BZ reaction. We have succeeded in making synthetic polymer gel move autonomously like a living organism. This experimental fact represents the great possibility of the chemical robot.

  20. The crystal structure of Erwinia amylovora AmyR, a member of the YbjN protein family, shows similarity to type III secretion chaperones but suggests different cellular functions.

    Science.gov (United States)

    Bartho, Joseph D; Bellini, Dom; Wuerges, Jochen; Demitri, Nicola; Toccafondi, Mirco; Schmitt, Armin O; Zhao, Youfu; Walsh, Martin A; Benini, Stefano

    2017-01-01

    AmyR is a stress and virulence associated protein from the plant pathogenic Enterobacteriaceae species Erwinia amylovora, and is a functionally conserved ortholog of YbjN from Escherichia coli. The crystal structure of E. amylovora AmyR reveals a class I type III secretion chaperone-like fold, despite the lack of sequence similarity between these two classes of protein and lacking any evidence of a secretion-associated role. The results indicate that AmyR, and YbjN proteins in general, function through protein-protein interactions without any enzymatic action. The YbjN proteins of Enterobacteriaceae show remarkably low sequence similarity with other members of the YbjN protein family in Eubacteria, yet a high level of structural conservation is observed. Across the YbjN protein family sequence conservation is limited to residues stabilising the protein core and dimerization interface, while interacting regions are only conserved between closely related species. This study presents the first structure of a YbjN protein from Enterobacteriaceae, the most highly divergent and well-studied subgroup of YbjN proteins, and an in-depth sequence and structural analysis of this important but poorly understood protein family.

  1. Optimal processing for gel electrophoresis images: Applying Monte Carlo Tree Search in GelApp.

    Science.gov (United States)

    Nguyen, Phi-Vu; Ghezal, Ali; Hsueh, Ya-Chih; Boudier, Thomas; Gan, Samuel Ken-En; Lee, Hwee Kuan

    2016-08-01

    In biomedical research, gel band size estimation in electrophoresis analysis is a routine process. To facilitate and automate this process, numerous software have been released, notably the GelApp mobile app. However, the band detection accuracy is limited due to a band detection algorithm that cannot adapt to the variations in input images. To address this, we used the Monte Carlo Tree Search with Upper Confidence Bound (MCTS-UCB) method to efficiently search for optimal image processing pipelines for the band detection task, thereby improving the segmentation algorithm. Incorporating this into GelApp, we report a significant enhancement of gel band detection accuracy by 55.9 ± 2.0% for protein polyacrylamide gels, and 35.9 ± 2.5% for DNA SYBR green agarose gels. This implementation is a proof-of-concept in demonstrating MCTS-UCB as a strategy to optimize general image segmentation. The improved version of GelApp-GelApp 2.0-is freely available on both Google Play Store (for Android platform), and Apple App Store (for iOS platform). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Polymer gel dosimeters with enhanced sensitivity for use in x-ray CT polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria BC V8W 3P6 (Canada); Hilts, M [Medical Physics, BC Cancer Agency-Vancouver Island Centre, Victoria BC V6R 2B6 (Canada); McAuley, K B, E-mail: jirasek@uvic.c [Department of Chemical Engineering, Queens University, Kingston, ON K7 L 3N6 (Canada)

    2010-09-21

    A primary limitation of current x-ray CT polymer gel dosimetry is the low contrast, and hence poor dose resolution, of dose images produced by the system. The low contrast is largely due to the low-dose sensitivity of current formulations of polymer gel for x-ray CT imaging. This study reports on the investigation of new dosimeter formulations with improved dose sensitivity for x-ray CT polymer gel dosimetry. We incorporate an isopropanol co-solvent into an N-isopropylacrylamide-based gel formulation in order to increase the total monomer/crosslinker concentration (%T) within the formulation. It is shown that gels of high %T exhibit enhanced dose sensitivity and dose resolutions over traditional formulations. The gels are shown to be temporally stable and reproducible. A single formulation (16%T) is used to demonstrate the capabilities of the x-ray CT polymer gel dosimetry system in measuring known dose distributions. A 1 L gel volume is exposed to three separate irradiations: a single-field percent depth dose, a two-field 'cross' and a three-field 'test case'. The first two irradiations are used to generate a dose calibration curve by which images are calibrated. The calibrated images are compared with treatment planning predictions and it is shown that the x-ray CT polymer gel dosimetry system is capable of capturing spatial and dose information accurately. The proposed new gel formulation is shown to be sensitive, stable and to improve the dose resolution over current formulations so as to provide a feasible gel for clinical applications of x-ray CT polymer gel dosimetry.

  3. Science objectives and first results from the SMART-1/AMIE multicolour micro-camera

    Science.gov (United States)

    Josset, J.-L.; Beauvivre, S.; Cerroni, P.; de Sanctis, M. C.; Pinet, P.; Chevrel, S.; Langevin, Y.; Barucci, M. A.; Plancke, P.; Koschny, D.; Almeida, M.; Sodnik, Z.; Mancuso, S.; Hofmann, B. A.; Muinonen, K.; Shevchenko, V.; Shkuratov, Yu.; Ehrenfreund, P.; Foing, B. H.

    The Advanced Moon micro-Imager Experiment (AMIE), on-board SMART-1, the first European mission to the Moon, is an imaging system with scientific, technical and public outreach objectives. The science objectives are to image the lunar South Pole, permanent shadow areas (ice deposit), eternal light (crater rims), ancient lunar non-mare volcanism, local spectrophotometry and physical state of the lunar surface, and to map high latitudes regions (south) mainly at far side (South Pole Aitken basin). The technical objectives are to perform a Laserlink experiment (detection of laser beam emitted by ESA/Tenerife ground station), flight demonstration of new technologies and on-board autonomy navigation. The public outreach and educational objectives are to promote planetary exploration and space. We present here the first results obtained during the cruise phase.

  4. Polymer gels and networks

    National Research Council Canada - National Science Library

    Osada, Yoshihito; Khokhlov, A. R

    2002-01-01

    ... or magnetic field, etc.). It was realized that not only can polymer gels absorb and hold a considerable volume of liquids, but they can also be forced to expel the absorbed liquid in a controlled manner. Of particular interest are hydrogels, i.e., polymer gels, which swell extensively in water. The most common hydrogels are polyelectrolyte gels: ...

  5. Preparation of continuous alumina gel fibres by aqueous sol–gel ...

    Indian Academy of Sciences (India)

    Abstract. Continuous alumina gel fibres were prepared by sol–gel method. The spinning sol was prepared by mixing aluminum nitrate, lactic acid and polyvinylpyrrolidone with a mass ratio of 10:3:1·5. Thermogravimetry– differential scanning calorimetry (TG–DSC), Fourier transform infrared (FTIR) spectra, X-ray diffraction ...

  6. Sealing wells with gel

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, E C

    1967-10-01

    A new system is being used in Mexico to temporarily plug producing wells. The temporary seal is a gel with a catalyst. The use of this temporary plug allows gas-lift wells to be taken off production in order to carry out emergency repairs. The gel solidifies by the action of the catalyst to a high temperature (70 - 150/sup 0/C). By locating the bottom of the tubing at the top of the production interval, the gel material will go into the permeable formation, and immediately set. When the gel has solidified, it seals off the horizon that must not be stimulated, and leaves the others exposed to the acid action. When the treatment is finished, the gel, by action of the catalyst, is liquefied and removed from the formation, being produced with the oil.

  7. Gel-eletroforese no diagnóstico da varíola Gel-electrophoresis in the smallpox diagnosis

    Directory of Open Access Journals (Sweden)

    Julio A. Mesquita

    1972-01-01

    Full Text Available O emprego de gel-eletroforese no diagnóstico da varíola, demonstrou ser ao menos trinta vezes (30X mais sensível que o teste de agar-gel, nas condições descritas (tabela I. Doze (12 espécimes, cujos testes convencionais de inoculação em ovos embrionados e de agar-gel resultaram positivos, foram testados em suas diluições originais congeladas por mais de um ano, sendo seis deles revelados por gel-eletroforese enquanto nenhum o foi por agar-gel (tabela II. Trinta e três (33 amostras isoladas no laboratório, foram testadas com material colhido de membrana cório-alantóica da primeira inoculação para o diagnóstico, conservado em glicerina 50%, resultando 15 positivas em gel-eletroforese e apenas 3 em agar-gel (tabela II. Os últimos 60 espécimes recebidos para diagnóstico, através a Campanha de Erradicação da Varíola, também resultaram negativos em gel-eletroforese, que não mostrou falsos-positivos nas condições descritas.The test of gel-electrophoresis applied to the pox virus group showed to be at least thirth times (30X more sensitive than agar-gel test on the described conditions (Table I. Twelve specimens, which were positives form Smallpox in the conventional tests of egg inoculation and agar-gel difusion test, have been screened in their original dilutions frozen for more than 1 year and six of them were still detectable by gel-eletrophoresis, while by agar-gel test any of them was positive (Table II. Thirty three Smallpox isolates have been tested with material from first egg inoculation (chorioallantoic membranes which have been stored in glycerin 50%, at - 15ºC. Fifteen of them were still positive by gel-electrophoresis and only 3 by agar-gel (Table II. The last 60 specimens received for diagnosis from Smallpox Erradication Campaign (CEV, were negatives by both tests. The gel-electrophoresis, did not show false-positives on described conditions.

  8. Instrumental texture profile analysis of gelatin gel extracted from grouper skin and commercial (bovine and porcine) gelatin gels.

    Science.gov (United States)

    Rahman, Mohammad Shafiur; Al-Mahrouqi, Abdullah Issa

    2009-01-01

    Mechanical compression was used to study the gelling characteristics of gelatin gels. Texture profile analysis (TPA) showed that the hardness of fish and mammalian gelatin increased significantly as the concentrations of gels increased. TPA attributes of 10% fish skin gel showed significant differences from those obtained from 20% and 30% gels. In bovine and porcine cases, such generic trends were not observed. Mechanical characteristics of 10% gels of gelatin from fish skin, determined from one cycle compression, were significantly lower than other sources of gelatin gels, while bovine and porcine gels did not show any significant differences. In the case of TPA, hardness of bovine gelatin gel was highest at 41 N for 10% gel, followed by porcine (30 N) then fish skin (5 N) gelatin gels. The gels prepared from different sources did not show any generic trends when all other mechanical attributes were considered.

  9. Rock and roll or rock and fall? Gendered framing of the rock and roll lifestyles of Amy Winehouse and Pete Doherty in British broadsheets

    NARCIS (Netherlands)

    P.P.L. Berkers (Pauwke); M. Eeckelaer (Merel)

    2014-01-01

    textabstractCombining insights from gender, popular music, and celebrity studies, this article addresses to what extent British broadsheets frame Amy Winehouse and Pete Doherty differently with regard to their rock and roll lifestyle. Our content analyses of The Guardian and The Independent indicate

  10. Compatibility between weak gel and microorganisms in weak gel-assisted microbial enhanced oil recovery.

    Science.gov (United States)

    Qi, Yi-Bin; Zheng, Cheng-Gang; Lv, Cheng-Yuan; Lun, Zeng-Min; Ma, Tao

    2018-03-20

    To investigate weak gel-assisted microbial flooding in Block Wang Long Zhuang in the Jiangsu Oilfield, the compatibility of weak gel and microbe was evaluated using laboratory experiments. Bacillus sp. W5 was isolated from the formation water in Block Wang Long Zhuang. The rate of oil degradation reached 178 mg/day, and the rate of viscosity reduction reached 75.3%. Strain W5 could produce lipopeptide with a yield of 1254 mg/L. Emulsified crude oil was dispersed in the microbial degradation system, and the average diameter of the emulsified oil particles was 18.54 μm. Bacillus sp. W5 did not affect the rheological properties of the weak gel, and the presence of the weak gel did not significantly affect bacterial reproduction (as indicated by an unchanged microbial biomass), emulsification (surface tension is 35.56 mN/m and average oil particles size is 21.38 μm), oil degradation (162 mg/day) and oil viscosity reduction (72.7%). Core-flooding experiments indicated oil recovery of 23.6% when both weak gel and Bacillus sp. W5 were injected into the system, 14.76% when only the weak gel was injected, and 9.78% with strain W5 was injected without the weak gel. The results demonstrate good compatibility between strains W5 and the weak gel and highlight the application potential of weak gel-assisted microbial flooding. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  11. High transparent shape memory gel

    Science.gov (United States)

    Gong, Jin; Arai, Masanori; Kabir, M. H.; Makino, Masato; Furukawa, Hidemitsu

    2014-03-01

    Gels are a new material having three-dimensional network structures of macromolecules. They possess excellent properties as swellability, high permeability and biocompatibility, and have been applied in various fields of daily life, food, medicine, architecture, and chemistry. In this study, we tried to prepare new multi-functional and high-strength gels by using Meso-Decoration (Meso-Deco), one new method of structure design at intermediate mesoscale. High-performance rigid-rod aromatic polymorphic crystals, and the functional groups of thermoreversible Diels-Alder reaction were introduced into soft gels as crosslinkable pendent chains. The functionalization and strengthening of gels can be realized by meso-decorating the gels' structure using high-performance polymorphic crystals and thermoreversible pendent chains. New gels with good mechanical properties, novel optical properties and thermal properties are expected to be developed.

  12. Influence of pre-cooking protein paste gelation conditions and post-cooking gel storage conditions on gel texture.

    Science.gov (United States)

    Paker, Ilgin; Matak, Kristen E

    2016-01-15

    Gelation conditions affect the setting of myofibrillar fish protein gels. Therefore the impact of widely applied pre-cooking gelation time/temperature strategies and post-cooking period on the texture and color of final protein gels was determined. Four pre-cooking gelation strategies (no setting time, 30 min at 25 °C, 1 h at 40 °C or 24 h at 4 °C) were applied to protein pastes (fish protein concentrate and standard functional additives). After cooking, texture and color were analyzed either directly or after 24 h at 4 °C on gels adjusted to 25 °C. No-set gels were harder, gummier and chewier (P cooking. Gel-setting conditions had a greater (P cooking stored gels in texture and color, depending on the pre-cooking gelation strategy. Pre-cooking gelation conditions will affect final protein gel texture and color, with gel stability benefiting from a gel-setting period. However, post-cooking storage may have a greater impact on final gels, with textural attributes becoming more consistent between all samples. © 2015 Society of Chemical Industry.

  13. Agar/gelatin bilayer gel matrix fabricated by simple thermo-responsive sol-gel transition method.

    Science.gov (United States)

    Wang, Yifeng; Dong, Meng; Guo, Mengmeng; Wang, Xia; Zhou, Jing; Lei, Jian; Guo, Chuanhang; Qin, Chaoran

    2017-08-01

    We present a simple and environmentally-friendly method to generate an agar/gelatin bilayer gel matrix for further biomedical applications. In this method, the thermally responsive sol-gel transitions of agar and gelatin combined with the different transition temperatures are exquisitely employed to fabricate the agar/gelatin bilayer gel matrix and achieve separate loading for various materials (e.g., drugs, fluorescent materials, and nanoparticles). Importantly, the resulting bilayer gel matrix provides two different biopolymer environments (a polysaccharide environment vs a protein environment) with a well-defined border, which allows the loaded materials in different layers to retain their original properties (e.g., magnetism and fluorescence) and reduce mutual interference. In addition, the loaded materials in the bilayer gel matrix exhibit an interesting release behavior under the control of thermal stimuli. Consequently, the resulting agar/gelatin bilayer gel matrix is a promising candidate for biomedical applications in drug delivery, controlled release, fluorescence labeling, and bio-imaging. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Chemical Gel for Surface Decontamination

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Moon, J. K.; Won, H. J.; Lee, K. W.; Kim, C. K.

    2010-01-01

    Many chemical decontamination processes operate by immersing components in aggressive chemical solutions. In these applications chemical decontamination technique produce large amounts of radioactive liquid waste. Therefore it is necessary to develop processes using chemical gels instead of chemical solutions, to avoid the well-known disadvantages of chemical decontamination techniques while retaining their high efficiency. Chemical gels decontamination process consists of applying the gel by spraying it onto the surface of large area components (floors, walls, etc) to be decontaminated. The gel adheres to any vertical or complex surface due to their thixotropic properties and operates by dissolving the radioactive deposit, along with a thin layer of the gel support, so that the radioactivity trapped at the surface can be removed. Important aspects of the gels are that small quantities can be used and they show thixitropic properties : liquid during spraying, and solid when stationary, allowing for strong adherence to surfaces. This work investigates the decontamination behaviors of organic-based chemical gel for SS 304 metallic surfaces contaminated with radioactive materials

  15. Sol-Gel Manufactured Energetic Materials

    Science.gov (United States)

    Simpson, Randall L.; Lee, Ronald S.; Tillotson, Thomas M.; Hrubesh, Lawrence W.; Swansiger, Rosalind W.; Fox, Glenn A.

    2005-05-17

    Sol-gel chemistry is used for the preparation of energetic materials (explosives, propellants and pyrotechnics) with improved homogeneity, and/or which can be cast to near-net shape, and/or made into precision molding powders. The sol-gel method is a synthetic chemical process where reactive monomers are mixed into a solution, polymerization occurs leading to a highly cross-linked three dimensional solid network resulting in a gel. The energetic materials can be incorporated during the formation of the solution or during the gel stage of the process. The composition, pore, and primary particle sizes, gel time, surface areas, and density may be tailored and controlled by the solution chemistry. The gel is then dried using supercritical extraction to produce a highly porous low density aerogel or by controlled slow evaporation to produce a xerogel. Applying stress during the extraction phase can result in high density materials. Thus, the sol-gel method can be used for precision detonator explosive manufacturing as well as producing precision explosives, propellants, and pyrotechnics, along with high power composite energetic materials.

  16. Thixotropic gel for vadose zone remediation

    Science.gov (United States)

    Rhia, Brian D [Augusta, GA

    2011-03-01

    A thixotropic gel suitable for use in subsurface bioremediation is provided along with a process of using the gel. The thixotropic gel provides a non-migrating injectable substrate that can provide below ground barrier properties. In addition, the gel components provide for a favorable environment in which certain contaminants are preferentially sequestered in the gel and subsequently remediated by either indigenous or introduced microorganisms.

  17. Meso-Decorated Switching-Knot Gels

    Science.gov (United States)

    Gong, Jin; Sawamura, Kensuke; Makino, Masato; Kabir, M. H.; Furukawa, Hidemitsu

    Gels are a new material having three-dimensional network structures of macromolecules. They possess excellent properties as swellability, high permeability and biocompatibility, and have been applied in various fields of daily life, food, medicine, architecture, and chemistry .In this study, we tried to prepare new multi-functional and high-strength gels by using Meso-Decoration (Meso-Deco), one new method of structure design at intermediate mesoscale. High-performance rigid-rod aromatic polymorphic crystals. The strengthening of gels can be realized by meso-decorating the gels' structure using high-performance polymorphic crystals. New gels with good mechanical properties, novel optical properties and thermal properties are expected to be developed.

  18. Structure of mineral gels

    International Nuclear Information System (INIS)

    Miranda Salvado, I.M.; Margaca, F.M.A.; Teixeira, J.

    1999-01-01

    Small Angle Neutron Scattering (SANS) measurements have been performed to investigate the nanoscale structure of materials of the systems xTiO 2 -(1-x)SiO 2 and xZrO 2 -(1-x)SiO 2 with x ≤ 10 mol % at different processing stages. The materials were prepared by sol-gel using the alkoxides method, in strong acidic conditions. Samples were studied as xerogels heat-treated at 120 and 850 deg. C and as wet gels at gel point and after aging. All samples showed identical microstructure at gel point, extended linear chains ∼10 nm long. The aged gel has a mass fractal structure with fractal dimension of 1.7 - 1.9. The 120 deg. C heat-treated xerogels show homogeneous oxide regions with mass fractal structure. For the 850 deg. C heat-treated xerogel the oxide regions average size has reduced and it has densified as compared to 120 deg. C heat-treated sample. (author)

  19. Cyanocobalamin Nasal Gel

    Science.gov (United States)

    ... to supply extra vitamin B12 to people who need unusually large amounts of this vitamin because they are pregnant or have certain diseases. ... Cyanocobalamin nasal gel will supply you with enough vitamin B12 only as ... it regularly. You may need to use cyanocobalamin nasal gel every week for ...

  20. Gels and gel-derived glasses in the system Na2O-B2O3-SiO2

    Science.gov (United States)

    Mukherjee, S. P.

    1983-01-01

    The containerless melting of high-purity multicomponent homogeneous gels and gel monoliths offers a unique approach to making ultrapure multicomponent optical glasses in the reduced gravity environment of space. Procedures for preparing and characterizing gels and gel-derived glasses in the system Na2O-B2O3-SiO2 are described. Preparation is based on the polymerization reactions of alkoxysilane with trimethyl borate or boric acid and a suitable sodium compound. The chemistry of the gelling process is discussed in terms of process parameters and the gel compositions. The physicochemical nature of gels prepared by three different procedures was found to be significantly different. Infrared absorption spectra indicate finite differences in the molecular structures of the different gels. The melting of the gel powders and the transformation of porous gel monoliths to transparent 'glass' without melting are described.

  1. Gel properties and interactions of Mesona blumes polysaccharide-soy protein isolates mixed gel: The effect of salt addition.

    Science.gov (United States)

    Wang, Wenjie; Shen, Mingyue; Liu, Suchen; Jiang, Lian; Song, Qianqian; Xie, Jianhua

    2018-07-15

    Effect of different salt ions on the gel properties and microstructure of Mesona blumes polysaccharide (MBP)-soy protein isolates (SPI) mixed gels were investigated. Sodium and calcium ions were chosen to explore their effects on the rheological behavior and gel properties of MBP-SPI mixed gels were evaluated by using rheological, X-ray diffraction, protein solubility determination, and microstructure analysis. Results showed that the addition of salt ions change the crystalline state of gels system, the crystal of gel was enhanced at low ion concentrations (0.005-0.01 M). The two peaks of gel characteristic at 8.9° and 19.9° almost disappeared at high salt ions concentrations (0.015-0.02 M), and new crystallization peaks appeared at around 30° and 45°. The elasticity, viscosity, gel strength, water holding capacity, and thermal stability of gel were increased at low ion concentration. Results showed that the main interactions which promoted gel formation and maintain the three-dimensional structure of the gel were electrostatic interactions, hydrophobic interactions, and disulfide interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Study of nuclear glasses alteration gel and synthesis of some model gels

    International Nuclear Information System (INIS)

    Ricol, S.

    1995-01-01

    This work deals with the general problem of alteration of the reference nuclear glass R7T7. Attention is paid particularly to the altered layer formed at the glass surface during alteration process. In opposition to previous works, related essentially to glass dissolution kinetics based on chemical analyses of lixiviated elements, this thesis deals with alteration problems through structural studies of the reference glass and derived gel. This approach allows the determination of mechanisms for the gel formation and a better understanding of the behaviour of glasses towards lixiviation. Both approaches appeared complementary. Based on several spectroscopic techniques, this work showed the particular role of cations such as calcium, zirconium and iron. Studies of silica-based synthetic gels showed the synergic effect of formers cation and of one highly coordinated cation. The variation of the wavenumber related to Si-O-Si asymmetric stretching vibration can be correlated to O/Si ratio for ternary systems Si/Na/Zr. On the contrary, the Si losses of the materials depend on the number of non-bridging oxygen atoms. In the perspective of long-term behaviour, the alteration gel presents better characteristics than initial glass. It is therefore a highly stable material in static conditions. In the same way, synthetic gels are materials with very low solubilities (much lower than the alteration gel) and could be used as confining matrices. (authors). refs., 71 figs., 37 tabs

  3. Dapsone gel 5% in combination with adapalene gel 0.1%, benzoyl peroxide gel 4% or moisturizer for the treatment of acne vulgaris: a 12-week, randomized, double-blind study.

    Science.gov (United States)

    Fleischer, Alan B; Shalita, Alan; Eichenfield, Lawrence F; Abramovits, William; Lucky, Anne; Garrett, Steven

    2010-01-01

    To evaluate the safety and efficacy of dapsone gel 5% in the treatment of acne when used in combination with adapalene gel 0.1%, benzoyl peroxide gel 4% or moisturizer. This was a twelve-week, randomized, double-blind study. Patients aged 12 years and older (n=301) applied dapsone gel twice daily and were randomly assigned (1:1:1) to one of three additional treatments, applied once daily. By week 12, dapsone gel combined with any of the three additional treatments reduced the mean number of inflammatory lesions. However, the authors did not detect a significant difference in the reduction of inflammatory lesions when dapsone was used in combination with adapalene gel or with benzoyl peroxide gel compared to the dapsone plus moisturizer combination group (P=0.052 for both versus moisturizer combination). Patients treated with dapsone gel combined with adapalene showed a significantly better response in reduction in non-inflammatory and total acne lesion count than those who received the moisturizer combination. Local adverse reactions in all three treatment groups were minimal and generally mild in severity. Dapsone gel in combination with adapalene gel or benzoyl peroxide gel is safe and well tolerated for the treatment of acne vulgaris.

  4. Silver nitrate based gel dosimeter

    International Nuclear Information System (INIS)

    Titus, D; Samuel, E J J; Srinivasan, K; Roopan, S M; Madhu, C S

    2017-01-01

    A new radiochromic gel dosimeter based on silver nitrate and a normoxic gel dosimeter was investigated using UV-Visible spectrophotometry in the clinical dose range. Gamma radiation induced the synthesis of silver nanoparticles in the gel and is confirmed from the UV-Visible spectrum which shows an absorbance peak at around 450 nm. The dose response function of the dosimeter is found to be linear upto12Gy. In addition, the gel samples were found to be stable which were kept under refrigeration. (paper)

  5. MR tomography of focal liver lesions using the superparamagnetic contrast agent AMI-25 at 1.5 tesla

    International Nuclear Information System (INIS)

    Duda, S.H.; Laniado, M.; Kopp, A.F.; Groenewaeller, E.; Aicher, K.P.; Pavone, P.; Jehle, E.; Claussen, C.D.

    1994-01-01

    Superparamagnetic iron oxide particles (AMI-25) were evaluated as a liver contrast agent in high-field MR imaging (1.5 T). 16 patients with up to 5 presumed focal liver lesions (liver metastases n=8, HCC n=5, Klatskin tumours n=2, FNH n=1) received 15 μmol Fe/kg BW intravenously and were examined via standard T 1 - and T 2 -weighted spin-echo sequences. Quantitative image analysis showed a post-contrast increase of the contrast-to-noise ratio (C/N) from 1.6 to 7.4 on SE 2,500/15 images (p [de

  6. Surface grafted chitosan gels. Part II. Gel formation and characterization

    DEFF Research Database (Denmark)

    Liu, Chao; Thormann, Esben; Claesson, Per M.

    2014-01-01

    Responsive biomaterial hydrogels attract significant attention due to their biocompatibility and degradability. In order to make chitosan based gels, we first graft one layer of chitosan to silica, and then build a chitosan/poly(acrylic acid) multilayer using the layer-by-layer approach. After...... cross-linking the chitosan present in the polyelectrolyte multilayer, poly(acrylic acid) is partly removed by exposing the multilayer structure to a concentrated carbonate buffer solution at a high pH, leaving a surface-grafted cross-linked gel. Chemical cross-linking enhances the gel stability against...... detachment and decomposition. The chemical reaction between gluteraldehyde, the cross-linking agent, and chitosan was followed in situ using total internal reflection Raman (TIRR) spectroscopy, which provided a molecular insight into the complex reaction mechanism, as well as the means to quantify the cross...

  7. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown

  8. Antimicrobial efficacy of alcohol-based hand gels.

    Science.gov (United States)

    Guilhermetti, M; Marques Wiirzler, L A; Castanheira Facio, B; da Silva Furlan, M; Campo Meschial, W; Bronharo Tognim, M C; Botelho Garcia, L; Luiz Cardoso, C

    2010-03-01

    In recent years, several commercial alcohol-based hand gels have appeared on the market to improve the hand-cleansing compliance of healthcare workers. Although the antimicrobial efficacy of these products has been reported in different countries, few studies have investigated this subject in Brazil. In this study, we assessed the antimicrobial efficacy of 12 alcohol-based hand gels produced in Brazil, containing 70% w/w or v/v ethyl alcohol as the active ingredient, according to the European Standard EN 1500 (EN 1500). The following alcohol gels were tested: Hand Gel, Voga Gel, Solumax Solugel, Doctor Clean, Rio Gel, Clear Gel, Sevengel, Hand CHC, Gel Bac, WBL-50 Gel, Sanigel and Soft Care Gel. In addition, 70% w/w ethyl alcohol and three alcohol-based hand rubs (Sterillium, Sterillium Gel, and Spitaderm), commonly used in Europe and effective according to EN 1500, were also tested. All the products tested, except for two, were approved by the EN 1500 test protocol with a 60s application. The results confirmed the antimicrobial efficacy of the majority of the alcohol gels produced in Brazil for hand hygiene of healthcare workers. Copyright 2009 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

  9. Agarose gel electrophoresis and polyacrylamide gel electrophoresis for visualization of simple sequence repeats.

    Science.gov (United States)

    Anderson, James; Wright, Drew; Meksem, Khalid

    2013-01-01

    In the modern age of genetic research there is a constant search for ways to improve the efficiency of plant selection. The most recent technology that can result in a highly efficient means of selection and still be done at a low cost is through plant selection directed by simple sequence repeats (SSRs or microsatellites). The molecular markers are used to select for certain desirable plant traits without relying on ambiguous phenotypic data. The best way to detect these is the use of gel electrophoresis. Gel electrophoresis is a common technique in laboratory settings which is used to separate deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) by size. Loading DNA and RNA onto gels allows for visualization of the size of fragments through the separation of DNA and RNA fragments. This is achieved through the use of the charge in the particles. As the fragments separate, they form into distinct bands at set sizes. We describe the ability to visualize SSRs on slab gels of agarose and polyacrylamide gel electrophoresis.

  10. Amy Caiazza, Mothers and Soldiers. Gender, Citizenship and Civil Society in Contemporary Russia. Routledge. New York and London 2002.

    Directory of Open Access Journals (Sweden)

    Elena Zdravomyslova

    2005-04-01

    Full Text Available This book examines the importance of gender and citizenship ideologies and the opportunities available for interest groups and related civic initiatives in relation to the role of conscripts mother’s in contemporary Russia. Amy Ciazza asks: what is the role of gender culture in the development of the Russian civil society? The author argues that gender-typing of citizenship and popular beliefs about the different civic obligations of men and women can be efficiently mobilized by interest grou...

  11. Preparation of zirconium molybdate gel for 99mTc gel generator

    International Nuclear Information System (INIS)

    Aliludin, Z.; Ohkubo, Masatake; Kushita, Kouhei

    1988-09-01

    Zirconium molybdate gel has excellent characteristics for use as column matrix material of 99m Tc generators. In this work, zirconium molybdate gels were prepared under different conditions; pH's of molybdate solutions from 2.5 to 7.0, Mo:Zr molar ratios from 0.7:1.0 to 1.3:1.0, drying temperatures from an ambient temperature to 200 deg C, and drying times from 1 h to 25 h. Contents of water, nitrate, molybdenum and zirconium were measured to examine the fundamental conditions in gel preparation. The Mo:Zr molar ratio was 1.0:1.0 for the most of gels obtained. A 99m Tc generator was prepared with an amorphous zirconium molybdate containing a tracer level of 99 Mo as column matrix material. Elution of 99m Tc was rapid and the average elution efficiency was 90 % for 6 ml elutions. Contents of radionuclidic impurities, Zr and Mo in the eluates, were low enough to meet the pharmacopoeia requirements for human use. (author)

  12. Ophthalmic gels: Past, present and future.

    Science.gov (United States)

    Al-Kinani, Ali A; Zidan, Ghada; Elsaid, Naba; Seyfoddin, Ali; Alani, Adam W G; Alany, Raid G

    2018-02-15

    Aqueous gels formulated using hydrophilic polymers (hydrogels) along with those based on stimuli responsive polymers (in situ gelling or gel forming systems) continue to attract increasing interest for various eye health-related applications. They allow the incorporation of a variety of ophthalmic pharmaceuticals to achieve therapeutic levels of drugs and bioactives at target ocular sites. The integration of sophisticated drug delivery technologies such as nanotechnology-based ones with intelligent and environment responsive systems can extend current treatment duration to provide more clinically relevant time courses (weeks and months instead of hours and days) which will inevitably reduce dose frequency, increase patient compliance and improve clinical outcomes. Novel applications and design of contact lenses and intracanalicular delivery devices along with the move towards integrating gels into various drug delivery devices like intraocular pumps, injections and implants has the potential to reduce comorbidities caused by glaucoma, corneal keratopathy, cataract, diabetic retinopathies and age-related macular degeneration. This review describes ophthalmic gelling systems with emphasis on mechanism of gel formation and application in ophthalmology. It provides a critical appraisal of the techniques and methods used in the characterization of ophthalmic preformed gels and in situ gelling systems along with a thorough insight into the safety and biocompatibility of these systems. Newly developed ophthalmic gels, hydrogels, preformed gels and in situ gelling systems including the latest in the area of stimuli responsive gels, molecularly imprinted gels, nanogels, 3D printed hydrogels; 3D printed devices comprising ophthalmic gels are covered. Finally, new applications of gels in the production of artificial corneas, corneal wound healing and hydrogel contact lenses are described. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Gel electrophoresis of inorganic cations

    International Nuclear Information System (INIS)

    Schoenhofer, F.; Grass, F.

    1978-01-01

    In order to be able to separate the largest possible amounts of substance, polyacryl amide gel (PAA) and silica gel are used as carrier for the electrophoresis. Milligramme quantities can easily be separated on PAA gel plates. Electrophoretic ion focussing considerably improves it. Separations of Sr/Y and lanthanoids were carried out. The behaviour of the readily soluble complexing agent acids on silica gel thin layers was minutely investigated and an interpretation of the focussing effect was derived. The conditions for separating radionuclides were optimized. A further improved separation can be achieved by a time sequence combination of normal electrophoresis and ion focussing. Selective isolation methods are advantageous to determine radionuclide traces in environmental samples. The selective adsorption on preformed deposits was transferred to electrophoresis. After pre-investigations on silica gel layers, strontium and barium could also be retained on PAA gel and radium on strontium sulphate in PAA, whereas the disturbing calcium can easily pass through. Cesium can also be retained by prussian blue in the electrophoresis. (orig.) [de

  14. Initial investigation of a novel light-scattering gel phantom for evaluation of optical CT scanners for radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Bosi, Stephen; Naseri, Pourandokht; Puran, Alicia; Davies, Justin; Baldock, Clive

    2007-01-01

    There is a need for stable gel materials for phantoms used to validate optical computerized tomography (CT) scanners used in conjunction with radiation-induced polymerizing gel dosimeters. Phantoms based on addition of light-absorbing dyes to gelatine to simulate gel dosimeters have been employed. However, to more accurately simulate polymerizing gels one requires phantoms that employ light-scattering colloidal suspensions added to the gel. In this paper, we present the initial results of using an optical CT scanner to evaluate a novel phantom in which radiation-exposed polymer gels are simulated by the addition of colloidal suspensions of varying turbidity. The phantom may be useful as a calibration transfer standard for polymer gel dosimeters. The tests reveal some phenomena peculiar to light-scattering gels that need to be taken into account when calibrating polymer gel dosimeters

  15. Sol-gel technology for biomedical engineering

    International Nuclear Information System (INIS)

    Podbielska, H.; Ulatowska-Jarza, A.

    2005-01-01

    Sol-gel derived silica possess many promising features, including low-temperature preparation procedure, porosity, chemical and physical stability. Applications exploiting porous materials to encapsulate sensor molecules, enzymes and many other compounds, are developing rapidly. In this paper some potential applications, with emphasis on biomedical and environmental ones, are reviewed. The material preparation procedure is described and practical remarks on silica-based sol-gels are included. It is reported that sol-gels with entrapped various molecules may be used in construction of implants and coatings with bioactive properties. It is shown how to exploit the sol-gel production route for construction of sol-gel coated fiberoptic applicators for laser therapy. The applications of bioactive materials are discussed, as well. It is demonstrated that it is possible to immobilize photosensitive compounds in sol-gel matrix without loosing their photoactivity. Some examples of sol-gel based biosensors are demonstrated, as well, showing their potential for detecting various gases, toxic substances, acidity, humidity, enzymes and biologically active agents. (authors)

  16. Water equivalence of polymer gel dosimeters

    International Nuclear Information System (INIS)

    Sellakumar, P.; James Jebaseelan Samuel, E.; Supe, Sanjay S.

    2007-01-01

    To evaluate the water equivalence and radiation transport properties of polymer gel dosimeters over the wide range of photon and electron energies 14 different types of polymer gels were considered. Their water equivalence was evaluated in terms of effective atomic number (Z eff ), electron density (ρ e ), photon mass attenuation coefficient (μ/ρ), photon mass energy absorption coefficient (μ en /ρ) and total stopping power (S/ρ) tot of electrons using the XCOM and the ESTAR database. The study showed that the effective atomic number of polymer gels were very close ( en /ρ for all polymer gels were in close agreement ( tot of electrons in polymer gel dosimeters were within 1% agreement with that of water. From the study we conclude that at lower energy (<80keV) the polymer gel dosimeters cannot be considered water equivalent and study has to be carried out before using the polymer gel for clinical application

  17. Gel nano-particulates against radioactivity

    International Nuclear Information System (INIS)

    Deroin, Ph.

    2004-01-01

    The Argonne research center (USA) has developed a 'super-gel' compound, a polymer close to those used in baby's diapers, which can reach a 90% efficiency in the radioactive decontamination of porous materials, like bricks or concrete. The contaminated materials are sprayed with a mixture of polymer gel and wetting agent with nano-particulates in suspension. Under the action of the wetting agent, radioactivity migrates from the pores to the gel and is trapped by the nano-particulates. The drying and recycling of the gel allows to reduce the volume of radioactive wastes. Short paper. (J.S.)

  18. Antibiotic-containing hyaluronic acid gel as an antibacterial carrier: Usefulness of sponge and film-formed HA gel in deep infection.

    Science.gov (United States)

    Matsuno, Hiroaki; Yudoh, Kazuo; Hashimoto, Masamichi; Himeda, Yasukazu; Miyoshi, Teruzo; Yoshida, Kaoru; Kano, Syogo

    2006-03-01

    We have developed a novel bioabsorbable antibacterial carrier using hyaluronic acid (HA) gel for prevention and treatment of orthopedic infections. In this study, we investigated the in vivo antibacterial effects of two forms of this new material, an HA gel sponge and an HA gel film. A titanium cylinder was inserted into the intramedullary cavity of each rabbit femur, along with an HA gel sponge or HA gel film containing antibiotics. The HA gel sponge contained gentamycin, vancomycin, tobramycin, or minomycin. The HA gel film contained gentamycin or vancomycin. After 0, 7, and 14 days, the rabbit bone marrow was collected, and the antibacterial activity of the HA gel was determined by agar diffusion test. As a control, we used Septocoll, a commercially available antibacterial carrier. Both the HA gel sponge and HA gel film exhibited antibacterial activity. The present results indicate that HA gel containing antibiotics is a clinically useful bioabsorbable antibacterial carrier. Copyright 2006 Orthopaedic Research Society.

  19. [Acute myocardial infarction in Morocco: FES-AMI registry data].

    Science.gov (United States)

    Akoudad, H; El Khorb, N; Sekkali, N; Mechrafi, A; Zakari, N; Ouaha, L; Lahlou, I

    2015-12-01

    Acute myocardial infarction is the most dangerous complication of coronary atherothrombosis. There are several disparities in regard to its management around the world. The aim of this study is to analyze the specificities of management of acute myocardial infarction in Morocco. FES-AMI (Fès Acute Myocardial Infarction) is a prospective monocentric registry conducted in cardiology department of Hassan II university hospital in Fès. In this registry, we enrolled patients with acute myocardial infarction who presented within 5 days after symptom onset. From January 2005 to August 2015, we enrolled 1835 patients. Seventy-five percent of patients were males and mean age was 60 years old. Fifty-one percent of patients were smokers, 27% were hypertensives and 14% were diabetics. Sixty-six percent of patients had more than 2 risk factors. Time from symptom onset to hospital admission was less than six hours for 40% of the patients. Thirty-six percent of patients were admitted more than twelve hours after the onset of chest pain. Only 37% of patients received reperfusion therapy, 31% with in-hospital thrombolysis and 6% with primary angioplasty. In-hospital mortality was 7.6%. The patients enrolled in our registry have late presentation of acute myocardial infarction and less rate of reperfusion therapy. Furthermore, the majority of our patients have multiple risk factors and this result underlines the failure of preventive interventions. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  20. Physical Properties of Silicone Gel Breast Implants.

    Science.gov (United States)

    Jewell, Mark L; Bengtson, Bradley P; Smither, Kate; Nuti, Gina; Perry, TracyAnn

    2018-04-28

    Surgical applications using breast implants are individualized operations to fill and shape the breast. Physical properties beyond shape, size, and surface texture are important considerations during implant selection. Compare form stability, gel material properties, and shell thickness of textured shaped, textured round, and smooth round breast implants from 4 manufacturers: Allergan, Mentor, Sientra, and Establishment Labs through bench testing. Using a mandrel height gauge, form stability was measured by retention of dimensions on device movement from a horizontal to vertical supported orientation. Dynamic response of gel material (gel cohesivity, resistance to gel deformation, energy absorption) was measured using a synchronized target laser following application of graded negative pressure. Shell thickness was measured using digital thickness gauge calipers. Form stability, gel material properties, and shell thickness differed across breast implants. Of textured shaped devices, Allergan Natrelle 410 exhibited greater form stability than Mentor MemoryShape and Sientra Shaped implants. Allergan Inspira round implants containing TruForm 3 gel had greater form stability, higher gel cohesivity, greater resistance to gel deformation, and lower energy absorption than those containing TruForm 2 gel and in turn, implants containing TruForm 1 gel. Shell thickness was greater for textured versus smooth devices, and differed across styles. Gel cohesivity, resistance to gel deformation, and energy absorption are directly related to form stability, which in turn determines shape retention. These characteristics provide information to aid surgeons choosing an implant based on surgical application, patient tissue characteristics, and desired outcome.

  1. The Effect of Gel Microstructure on Simulated Gastric Digestion of Protein Gels

    NARCIS (Netherlands)

    Opazo-Navarrete, Mauricio; Altenburg, Marte D.; Boom, Remko M.; Janssen, Anja E.M.

    2018-01-01

    The objective of this study was to analyse the impact of the gel structure obtained by different heat-induced temperatures on the in vitro gastric digestibility at pH 2. To achieve this, gels were prepared from soy protein, pea protein, albumin from chicken egg white and whey protein isolate at

  2. Gel polymer electrolytes for batteries

    Science.gov (United States)

    Balsara, Nitash Pervez; Eitouni, Hany Basam; Gur, Ilan; Singh, Mohit; Hudson, William

    2014-11-18

    Nanostructured gel polymer electrolytes that have both high ionic conductivity and high mechanical strength are disclosed. The electrolytes have at least two domains--one domain contains an ionically-conductive gel polymer and the other domain contains a rigid polymer that provides structure for the electrolyte. The domains are formed by block copolymers. The first block provides a polymer matrix that may or may not be conductive on by itself, but that can soak up a liquid electrolyte, thereby making a gel. An exemplary nanostructured gel polymer electrolyte has an ionic conductivity of at least 1.times.10.sup.-4 S cm.sup.-1 at 25.degree. C.

  3. Influences of AMY1 gene copy number and protein expression on salivary alpha-amylase activity before and after citric acid stimulation in splenic asthenia children.

    Science.gov (United States)

    Yang, Zemin; Lin, Jing; Chen, Longhui; Zhang, Min; Yang, Xiaorong; Chen, Weiwen

    2015-06-01

    To compare the correlations between salivary alpha-amylase (sAA) activity and amylase, alpha 1 (salivary) gene (AMYl) copy number or its gene expression between splenic asthenia and healthy children, and investigate the reasons of attenuated sAA activity ratio before and after citric acid stimulation in splenic asthenia children. Saliva samples from 20 splenic asthenia children and 29 healthy children were collected before and after citric acid stimulation. AMYl copy number, sAA activity, and total sAA and glycosylated sAA contents were determined, and their correlations were analyzed. Although splenic asthenia and healthy children had no differences in AMY1 copy number, splenic asthenia children had positive correlations between AMY1 copy number and sAA activity before or after citric acid stimulation. Splenic asthenia children had a higher sAA glycosylated proportion ratio and glycosylated sAA content ratio, while their total sAA content ratio and sAA activity ratio were lower compared with healthy children. The glycosylated sAA content ratio was higher than the total sAA content ratio in both groups. Splenic asthenia and healthy children had positive correlations between total sAA or glycosylated sAA content and sAA activity. However, the role played by glycosylated sAA content in sAA activity in healthy children increased after citric acid stimulation, while it decreased in splenic asthenia children. Genetic factors like AMY1 copy number variations, and more importantly, sAA glycosylation abnormalities leading to attenuated sAA activity after citric acid stimulation, which were the main reasons of the attenuated sAA activity ratio in splenic asthenia children compared with healthy children.

  4. Comparative study on the effects of negatively-charged biopolymers on chitosan-based gels for the development of instantaneous gels

    International Nuclear Information System (INIS)

    Jimeno, Austin Ed B.; Chakraborty, Soma

    2015-01-01

    Polymeric electrolytic complexes are solutions of charged/ionized chains. These solutions of positive and negative charge can be combined to make instantaneous networks bonded by electrostatic interactions, a gel network. These electrostatic interaction allows for easy application in injectable gels as the network can be temporarily distributed with the application of force and reformed on the relief of it. Possible applications for these injectable gels include drug delivery and wound-healing. κ-Carrageenan, dextran sulfate, alginate, and chitosan are polyelectrolytic biocompatible polymers which are widely studied and used for a variety of biomedical applications. Gel networks are made by combining a negatively-charged (κ-Carrageenan, dextran sulfate, or alginate) and positively charged (chitosan) solutions. The strong electrostatic interaction between the opposite charges from the gel network and the inherent biocompatibility of the polymers allow future biomedical applications. Quat 188-modified chitosan has additional sites for electrostatic bonding, can be dissolved in neutral, basic, and acidic pH, and has shown inherent antibacterial activity. The objectives of this study are the following: to formulate chitosan-based gels mixing solutions of chitosan with solutions of either κ-Carrageenan, dextran sulfate, or alginate, study the gelation of the gels as function of time and pH (4, 7, and 9) using UV-Vis, characterize the chitosan-based gels through DSC and DMA, characterize the physiological degradation of the chitosan-based gels, and compare results with those from Quat 188-modified chitosan-based gels. Polyelectrolytic solutions of chitosan and negatively-charged biopolymer of similar viscosities were mixed. It was determined from the UV-Vis spectroscopy of the chitosan-carrageenan gels under pH7 buffer that the increase of concentration by a factor of 5 for 0.006M-0.0095M and 1.25 for 0.0095M-0.0150M Chitosan-Carrageenan gels improved gelation by the

  5. Research on pre-staining gel electrophoresis

    International Nuclear Information System (INIS)

    Zhong Ruibo; Liu Yushuang; Zhang Ping; Liu Jingran; Zhao Guofen; Zhang Feng

    2014-01-01

    Background: Gel electrophoresis is a powerful biochemical separation technique. Most biological molecules are completely transparent in the visible region of light, so it is necessary to use staining to show the results after gel electrophoresis, and the general steps of conventional staining methods are time-consuming. Purpose: We try to develop a novel approach to simplify the gel electrophoresis: Pre-Staining Gel Electrophoresis (PSGE), which can make the gel electrophoresis results monitored in real time. Methods: Pre-stain the protein samples with Coomassie Brilliant Blue (CBB) for 30 min before loading the sample into the gel well. Results and Conclusion: PSGE can be successfully used to analyze the binding efficiency of Bovine Serum Albumin (BSA) and amphiphilic polymer via chemical coupling and physical absorption, and the double PSGE also shows a great potential in bio-analytical chemistry. (authors)

  6. Purification of Peptide Components including Melittin from Bee Venom using gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Young Chon Choi

    2006-06-01

    Full Text Available Objectives : This study was conducted to carry out Purification of Melittin and other peptide components from Bee Venom using gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis Methods : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. Results : Melittin and other peptide components were separated from bee venom by using gel filtration chromatography on Sephadex G-50 column in 0.05M ammonium acetate buffer. The fractions obtained from gel filtration chromatography was analyzed by using SDS-PAGE and propionic acid/urea polyacrylamide gel electrophoresis. The melittin obtained from the gel filtration contained residual amount of phospholipase A2 and a protein with molecular weight of 6,000. The contaminating proteins were removed by the second gel filtration chromatography. Conclusion : Gel filtration chromatography and propionic acid/urea polyacrylamide gel electrophoresis are useful to separate peptide components including melittin from bee venom.

  7. Encapsulation of nanoclusters in dried gel materials via an inverse micelle/sol gel synthesis

    Science.gov (United States)

    Martino, Anthony; Yamanaka, Stacey A.; Kawola, Jeffrey S.; Showalter, Steven K.; Loy, Douglas A.

    1998-01-01

    A dried gel material sterically entrapping nanoclusters of a catalytically active material and a process to make the material via an inverse micelle/sol-gel synthesis. A surfactant is mixed with an apolar solvent to form an inverse micelle solution. A salt of a catalytically active material, such as gold chloride, is added along with a silica gel precursor to the solution to form a mixture. To the mixture are then added a reducing agent for the purpose of reducing the gold in the gold chloride to atomic gold to form the nanoclusters and a condensing agent to form the gel which sterically entraps the nanoclusters. The nanoclusters are normally in the average size range of from 5-10 nm in diameter with a monodisperse size distribution.

  8. Polymer gel dosimeter with AQUAJOINT® as hydrogel matrix

    Science.gov (United States)

    Maeyama, Takuya; Ishida, Yasuhiro; Kudo, Yoshihiro; Fukasaku, Kazuaki; Ishikawa, Kenichi L.; Fukunishi, Nobuhisa

    2018-05-01

    We report a polymer gel dosimeter based on a new gel matrix (AQUAJOINT®) that is a thermo-irreversible hydrogel formed by mixing two types of water-based liquids at room temperature. Normoxic N-vinylpyrrolidone-based polymer gels were prepared with AQUAJOINT® instead of gelatin. This AQUAJOINT®-based gel dosimeter exhibits a 2.5-fold increase in sensitivity over a gelatin-based gel dosimeter and a linear dose-response in the dose range of 0-8 Gy. This gel has heat resistance in a jar and controlled gel properties such as viscoelastic and mechanical characters, which may be useful for deformable polymer gel dosimetry.

  9. Nanocrystal/sol-gel nanocomposites

    Science.gov (United States)

    Petruska, Melissa A [Los Alamos, NM; Klimov, Victor L [Los Alamos, NM

    2007-06-05

    The present invention is directed to solid composites including colloidal nanocrystals within a sol-gel host or matrix and to processes of forming such solid composites. The present invention is further directed to alcohol soluble colloidal nanocrystals useful in formation of sol-gel based solid composites.

  10. Betwixt and Between Past and Present: Cultural and Generic Hybridity in the Fiction of Amy Tan and Mary Yukari Waters

    OpenAIRE

    Rania Youssef

    2013-01-01

    Amy Tan and Mary Yukari Waters are both Asian-Americans who portray hybridity in their short stories which depict the shifting identities of the self. But do the internal categories of gender, race and ethnicity help in the coherence or do they add to the fragmentation of diverse identities? It is the dynamics of this critique of multiple identification and hybrid cultures that is being traced here in this study and how all this is reflected in narrative responses to such conditions of ...

  11. Comparison effect of azithromycin gel 2% with clindamycin gel 1% in patients with acne

    Directory of Open Access Journals (Sweden)

    Fatemeh Mokhtari

    2016-01-01

    Conclusion: Azithromycin gel has medical impact at least similar to Clindamycin Gel in treatment of mild to moderate acne vulgaris, and it may be consider as suitable drug for resistant acne to conventional topical therapy.

  12. Sol-gel synthesis of hydroxyapatite; Sintese de hidroxiapatita via sol-gel

    Energy Technology Data Exchange (ETDEWEB)

    Zupanski, M.D.; Lucena, M.P.P.; Bergmann, C.P., E-mail: michelledunin@yahoo.com.b [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2010-07-01

    Hydroxyapatite (HAp) has been established as the calcium phosphate based compound with most applications in the biological field. Among the numerous techniques for synthesis of HAp, the sol-gel processing route affords great control over purity and formed phases using low processing temperatures. In addition, the sol-gel approach offers an option for homogeneous HAp coating on metal substrates, as well as the ability to generate nanocrystalline powders. In this work, the sol-gel synthesis of HAp was investigated employing triethyl phosphate and calcium nitrate tetrahydrate as phosphorous and calcium precursors, respectively. The aging effect on phase composition and powder morphology of the final product was studied in terms of temperature and aging time. The powders were studied by using X-ray diffraction, Fourier transform infrared spectroscopy, particle size distribution by laser diffraction and scanning electron microscopy. (author)

  13. K-Basin gel formation studies

    International Nuclear Information System (INIS)

    Beck, M.A.

    1998-01-01

    A key part of the proposed waste treatment for K Basin sludge is the elimination of reactive uranium metal by dissolution in nitric acid (Fkirnent, 1998). It has been found (Delegard, 1998a) that upon nitric acid dissolution of the sludge, a gel sometimes forms. Gels are known to sometimes impair solid/liquid separation and/or material transfer. The purpose of the work reported here is to determine the cause(s) of the gel formation and to determine operating parameters for the sludge dissolution that avoid formation of gel. This work and related work were planned in (Fkunent, 1998), (Jewett, 1998) and (Beck, 1998a). This report describes the results of the tests in (Beck, 1998a) with non-radioactive surrogates

  14. Rubber-like poly(vinyl alcohol) gel

    Energy Technology Data Exchange (ETDEWEB)

    Nambu, Masao (Nippon Oil Co. Ltd., Yokohama (Japan). Central Technical Research Lab.)

    1990-09-01

    Anomalous poly (vinyl alcohol) gel has been found in our laboratory since 1980. The gel is prepared by repeated freezing (or freeze-dehydration) of aqueous poly (vinyl alcohol). Experiments establish the fact that anomalous gel is never produced in the course of freezing, but during sustained thawing the gelation does occur. Moreover, it was found that the softening point of the gel increases at 37degC. It is assumed that crystal nuclei are generated on freezing, then on thawing, some of them grow to very fine crystals which act as polymer network-knots (cross-linking). Additional freezing provide other seeds, which grow similarly, and these are accumulated until rubber-like gel is produced. The gel was always water-resistant at 37degC, and the potassium permanganate consumption of the extracted water layer remained far below the official restricted value for medical materials. The gel can be sterilized with gamma-rays or chlorhexidine. Moreover, it satisfies the official standards of acute toxicity, pyrogen, intracutaneous reaction, hemolyzation, and intracorporeal implantation, respectively. Applications to adhesion-preventing membrane (for joint or pericardium), tamponade (for jaw defects), electrode (for electroretinogram or artificial inner ear), artificial denture base and phantoms for magnetic resonance imaging were examined. (author) 54 refs.

  15. Physical and chemical properties of gels. Application to protein nucleation control in the gel acupuncture technique

    Science.gov (United States)

    Moreno, Abel; Juárez-Martínez, Gabriela; Hernández-Pérez, Tomás; Batina, Nikola; Mundo, Manuel; McPherson, Alexander

    1999-09-01

    In this work, we present a new approach using analytical and optical techniques in order to determine the physical and chemical properties of silica gel, as well as the measurement of the pore size in the network of the gel by scanning electron microscopy. The gel acupuncture technique developed by García-Ruiz et al. (Mater. Res. Bull 28 (1993) 541) García-Ruiz and Moreno (Acta Crystallogr. D 50 (1994) 484) was used throughout the history of crystal growth. Several experiments were done in order to evaluate the nucleation control of model proteins (thaumatin I from Thaumatococcus daniellii, lysozyme from hen egg white and catalase from bovine liver) by the porous network of the gel. Finally, it is shown how the number and the size of the crystals obtained inside X-ray capillaries is controlled by the size of the porous structure of the gel.

  16. Basic investigations on LCV micelle gel

    International Nuclear Information System (INIS)

    Ebenezer, S B; Rafic, M K; Ravindran, P B

    2013-01-01

    The aim of this study was to investigate the feasibility of using Leuco Crystal Violet (LCV) based micelle gel dosimeter as a quality assurance tool in radiotherapy applications. Basic properties such as absorption coefficient and diffusion of LCV gel phantom over time were evaluated. The gel formulation consisted of 25 mM Trichloroacetic acid, 1mM LCV, 4 mM Triton X-100, 4% gelatin by mass and distilled water. The advantages of using this gel are its tissue equivalence, easy and less preparation time, lower diffusion rate and it can be read with an optical scanner. We were able to reproduce some of the results of Babic et al. The peak absorption was found to be at 600 nm and hence a matrix of yellow LEDs was used as light source. The profiles obtained from projection images confirmed the diffusion of LCV gel after 6 hours of irradiation. Hence the LCV gel phantom should be read before 6 hours post irradiation to get accurate dose information as suggested previously.

  17. Cells on Gels: Cell Behavior at the Air-Gel Interface

    Science.gov (United States)

    O'Bryan, Christopher; Hormel, Tristan; Bhattacharjee, Tapomoy; Sawyer, W.; Angelini, Thomas

    Numerous different types of cells are often grown at air-liquid interfaces. For example, a common way to create cell spheroids is to disperse cells in a droplet of liquid media that hangs from the lid of a culture dish - the ``hanging drop'' method. Some types of epithelial cells form monolayers at the bottom of hanging drops, instead of spheroids. Corneal epithelial cells stratify and exhibit a tissue-like phenotype when attached to liquid permeable culture surfaces positioned at the air-liquid media interface (air-lifted culture). These widely used culture methods make experimentation challenging - imaging through hanging drops and air-lifted culture dishes is prohibitive. However, similar results may be achieved by culturing cells on hydrogel surfaces at the air-gel interface. In this talk we will describe a method for culturing cells at air-gel interfaces. We seed human corneal epithelial cells (hTCEpi) onto the surfaces of hydrogel networks and jammed microgels, exposed to air. Preliminary observations of cell behavior at the air-gel interface will be presented.

  18. Synthesis and application of silica gel modified with alkoxyalcohols. Alkoxyalcohol shushoku silica gel no gosei to riyo

    Energy Technology Data Exchange (ETDEWEB)

    Moriguchi, T.; Ishiguro, H.; Matsubara, Y.; Yoshihara, M.; Maeshima, T.; Ito, S. (Kinki University, Osaka (Japan). Faculty of Science and Engineering)

    1991-08-20

    Several kinds of silica gel modified by alkoxyalcohols were synthesized by refluxing and dehyration and the organic reactions were studied when these silica gels were used as the catalyst. It could be confirmed by FT-IR spectra, DTA and elementary analysis that alkoxylalcohols adhere to the surface of silica gels without any decomposition. The acetate was produced by using alkyl halides. It was found that the modified silica gels had clearly the catalytic action for the reaction with n-hexyl bromide and dibromoethane although unmodified silica gels did not show the catalytic action. The reducing reaction of carbonyl compounds was carried out. The reaction proceeded at 25 centigrade for acetophenone, cyclohexanone, 1-indanone and 2-octanone to produce the corresponding reduction products. 11 refs., 5 figs., 4 tabs.

  19. Integration of gel-based and gel-free proteomic data for functional analysis of proteins through Soybean Proteome Database

    KAUST Repository

    Komatsu, Setsuko

    2017-05-10

    The Soybean Proteome Database (SPD) stores data on soybean proteins obtained with gel-based and gel-free proteomic techniques. The database was constructed to provide information on proteins for functional analyses. The majority of the data is focused on soybean (Glycine max ‘Enrei’). The growth and yield of soybean are strongly affected by environmental stresses such as flooding. The database was originally constructed using data on soybean proteins separated by two-dimensional polyacrylamide gel electrophoresis, which is a gel-based proteomic technique. Since 2015, the database has been expanded to incorporate data obtained by label-free mass spectrometry-based quantitative proteomics, which is a gel-free proteomic technique. Here, the portions of the database consisting of gel-free proteomic data are described. The gel-free proteomic database contains 39,212 proteins identified in 63 sample sets, such as temporal and organ-specific samples of soybean plants grown under flooding stress or non-stressed conditions. In addition, data on organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored. Furthermore, the database integrates multiple omics data such as genomics, transcriptomics, metabolomics, and proteomics. The SPD database is accessible at http://proteome.dc.affrc.go.jp/Soybean/. Biological significanceThe Soybean Proteome Database stores data obtained from both gel-based and gel-free proteomic techniques. The gel-free proteomic database comprises 39,212 proteins identified in 63 sample sets, such as different organs of soybean plants grown under flooding stress or non-stressed conditions in a time-dependent manner. In addition, organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored in the gel-free proteomics database. A total of 44,704 proteins, including 5490 proteins identified using a gel-based proteomic technique, are stored in the SPD. It accounts for approximately 80% of all

  20. Integration of gel-based and gel-free proteomic data for functional analysis of proteins through Soybean Proteome Database.

    Science.gov (United States)

    Komatsu, Setsuko; Wang, Xin; Yin, Xiaojian; Nanjo, Yohei; Ohyanagi, Hajime; Sakata, Katsumi

    2017-06-23

    The Soybean Proteome Database (SPD) stores data on soybean proteins obtained with gel-based and gel-free proteomic techniques. The database was constructed to provide information on proteins for functional analyses. The majority of the data is focused on soybean (Glycine max 'Enrei'). The growth and yield of soybean are strongly affected by environmental stresses such as flooding. The database was originally constructed using data on soybean proteins separated by two-dimensional polyacrylamide gel electrophoresis, which is a gel-based proteomic technique. Since 2015, the database has been expanded to incorporate data obtained by label-free mass spectrometry-based quantitative proteomics, which is a gel-free proteomic technique. Here, the portions of the database consisting of gel-free proteomic data are described. The gel-free proteomic database contains 39,212 proteins identified in 63 sample sets, such as temporal and organ-specific samples of soybean plants grown under flooding stress or non-stressed conditions. In addition, data on organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored. Furthermore, the database integrates multiple omics data such as genomics, transcriptomics, metabolomics, and proteomics. The SPD database is accessible at http://proteome.dc.affrc.go.jp/Soybean/. The Soybean Proteome Database stores data obtained from both gel-based and gel-free proteomic techniques. The gel-free proteomic database comprises 39,212 proteins identified in 63 sample sets, such as different organs of soybean plants grown under flooding stress or non-stressed conditions in a time-dependent manner. In addition, organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored in the gel-free proteomics database. A total of 44,704 proteins, including 5490 proteins identified using a gel-based proteomic technique, are stored in the SPD. It accounts for approximately 80% of all predicted proteins from

  1. Integration of gel-based and gel-free proteomic data for functional analysis of proteins through Soybean Proteome Database

    KAUST Repository

    Komatsu, Setsuko; Wang, Xin; Yin, Xiaojian; Nanjo, Yohei; Ohyanagi, Hajime; Sakata, Katsumi

    2017-01-01

    The Soybean Proteome Database (SPD) stores data on soybean proteins obtained with gel-based and gel-free proteomic techniques. The database was constructed to provide information on proteins for functional analyses. The majority of the data is focused on soybean (Glycine max ‘Enrei’). The growth and yield of soybean are strongly affected by environmental stresses such as flooding. The database was originally constructed using data on soybean proteins separated by two-dimensional polyacrylamide gel electrophoresis, which is a gel-based proteomic technique. Since 2015, the database has been expanded to incorporate data obtained by label-free mass spectrometry-based quantitative proteomics, which is a gel-free proteomic technique. Here, the portions of the database consisting of gel-free proteomic data are described. The gel-free proteomic database contains 39,212 proteins identified in 63 sample sets, such as temporal and organ-specific samples of soybean plants grown under flooding stress or non-stressed conditions. In addition, data on organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored. Furthermore, the database integrates multiple omics data such as genomics, transcriptomics, metabolomics, and proteomics. The SPD database is accessible at http://proteome.dc.affrc.go.jp/Soybean/. Biological significanceThe Soybean Proteome Database stores data obtained from both gel-based and gel-free proteomic techniques. The gel-free proteomic database comprises 39,212 proteins identified in 63 sample sets, such as different organs of soybean plants grown under flooding stress or non-stressed conditions in a time-dependent manner. In addition, organellar proteins identified in mitochondria, nuclei, and endoplasmic reticulum are stored in the gel-free proteomics database. A total of 44,704 proteins, including 5490 proteins identified using a gel-based proteomic technique, are stored in the SPD. It accounts for approximately 80% of all

  2. Sol-gel processing to form doped sol-gel monoliths inside hollow core optical fiber and sol-gel core fiber devices made thereby

    Science.gov (United States)

    Shaw, Harry C. (Inventor); Ott, Melanie N. (Inventor); Manuel, Michele V. (Inventor)

    2002-01-01

    A process of fabricating a fiber device includes providing a hollow core fiber, and forming a sol-gel material inside the hollow core fiber. The hollow core fiber is preferably an optical fiber, and the sol-gel material is doped with a dopant. Devices made in this manner includes a wide variety of sensors.

  3. Sol-gel additive for systems with inorganic binders

    International Nuclear Information System (INIS)

    Akstinat, M.; Antenen, D.; Suter, W.

    1996-01-01

    A sol-gel additive for inorganic binder systems and sol-gel process for producing air-placed concrete and mortar by using such sol-gel additives are disclosed. Sol-gel additives for gel-derived inorganic binder systems (for example plaster, cement, lime, special slags, etc.) marked improve the consistency of such binder systems during processing or allow their consistency to be regulated. In addition, these sol-gel additives regulate setting times and substantially improve durability (chemical resistance, reduced permeability) and the mechanical properties of the set binder system. (author)

  4. Sol-gel bonding of silicon wafers

    International Nuclear Information System (INIS)

    Barbe, C.J.; Cassidy, D.J.; Triani, G.; Latella, B.A.; Mitchell, D.R.G.; Finnie, K.S.; Short, K.; Bartlett, J.R.; Woolfrey, J.L.; Collins, G.A.

    2005-01-01

    Sol-gel bonds have been produced between smooth, clean silicon substrates by spin-coating solutions containing partially hydrolysed silicon alkoxides. The two coated substrates were assembled and the resulting sandwich fired at temperatures ranging from 60 to 600 deg. C. The sol-gel coatings were characterised using attenuated total reflectance Fourier transform infrared spectroscopy, ellipsometry, and atomic force microscopy, while the corresponding bonded specimens were investigated using scanning electron microscopy and cross-sectional transmission electron microscopy. Mechanical properties were characterised using both microindentation and tensile testing. Bonding of silicon wafers has been successfully achieved at temperatures as low as 60 deg. C. At 300 deg. C, the interfacial fracture energy was 1.55 J/m 2 . At 600 deg. C, sol-gel bonding provided superior interfacial fracture energy over classical hydrophilic bonding (3.4 J/m 2 vs. 1.5 J/m 2 ). The increase in the interfacial fracture energy is related to the increase in film density due to the sintering of the sol-gel interface with increasing temperature. The superior interfacial fracture energy obtained by sol-gel bonding at low temperature is due to the formation of an interfacial layer, which chemically bonds the two sol-gel coatings on each wafer. Application of a tensile stress on the resulting bond leads to fracture of the samples at the silicon/sol-gel interface

  5. Influence of Uranium and Polivinyl Alcohol Concentration in the Feed of Sol Gel Process on the Gel Spherical Product

    International Nuclear Information System (INIS)

    Indra Suryawan; Endang Susiantini

    2007-01-01

    The gel particles have been made at various uranium and polyvinyl alcohol concentration in the sol gel process. The variables of uranium concentration were 0.3; 0.5; 0.7; 0.9; 1.1; 1.3; 1.5; 1.7; 1.9 and 2.1 M The variables of polyvinyl alcohol concentration were 0.3; 0.6; 0.9; 1.2; 1.5; 1.8; 2.1 and 2.4 M After drying the sol gel process products were heated at 300, 500 and 750°C during 4 hours. The gel particles were characterized using an optic microscope to know the shape and condition morphology of gel. From experimental result using uranium concentration of 0.3 until 2.1 M and polyvinyl alcohol of 1.8 until 2.4 M spherical and gel was formed elastic, after heating at 750°C it was unbreakable. At the concentration of polyvinyl alcohol from 0.3 to 0.5 M, the gel product was soft and broken after being dried. At the concentration of polyvinyl alcohol from 0.6 to 0.8 M, the dried gel product was not perfect. At the concentration of polyvinyl alcohol from 0.9 to 1.7 M, the gel product of gelation process was spherical and it was broken after being heated up to 300°C. (author)

  6. Yield stress determination of a physical gel

    DEFF Research Database (Denmark)

    Hvidt, Søren

    2013-01-01

    Pluronic F127 solutions form gels in water with high elastic moduli. Pluronic gels can, however, only withstand small deformations and stresses. Different steady shear and oscillatory methods traditionally used to determine yield stress values are compared. The results show that the yield stresses...... values of these gels depend on test type and measurement time, and no absolute yield stress value can be determined for these physical gels....

  7. Proactive Approach for Safe Use of Antimicrobial Coatings in Healthcare Settings: Opinion of the COST Action Network AMiCI

    Directory of Open Access Journals (Sweden)

    Merja Ahonen

    2017-03-01

    Full Text Available Infections and infectious diseases are considered a major challenge to human health in healthcare units worldwide. This opinion paper was initiated by EU COST Action network AMiCI (AntiMicrobial Coating Innovations and focuses on scientific information essential for weighing the risks and benefits of antimicrobial surfaces in healthcare settings. Particular attention is drawn on nanomaterial-based antimicrobial surfaces in frequently-touched areas in healthcare settings and the potential of these nano-enabled coatings to induce (ecotoxicological hazard and antimicrobial resistance. Possibilities to minimize those risks e.g., at the level of safe-by-design are demonstrated.

  8. Modification of gel architecture and TBE/TAE buffer composition to minimize heating during agarose gel electrophoresis.

    Science.gov (United States)

    Sanderson, Brian A; Araki, Naoko; Lilley, Jennifer L; Guerrero, Gilberto; Lewis, L Kevin

    2014-06-01

    Agarose gel electrophoresis of DNA and RNA is routinely performed using buffers containing either Tris, acetate, and EDTA (TAE) or Tris, borate, and EDTA (TBE). Gels are run at a low, constant voltage (∼10 V/cm) to minimize current and asymmetric heating effects, which can induce band artifacts and poor resolution. In this study, alterations of gel structure and conductive media composition were analyzed to identify factors causing higher electrical currents during horizontal slab gel electrophoresis. Current was reduced when thinner gels and smaller chamber buffer volumes were used, but was not influenced by agarose concentration or the presence of ethidium bromide. Current was strongly dependent on the amount and type of EDTA used and on the concentrations of the major acid-base components of each buffer. Interestingly, resolution and the mobilities of circular versus linear plasmid DNAs were also affected by the chemical form and amount of EDTA. With appropriate modifications to gel structure and buffer constituents, electrophoresis could be performed at high voltages (20-25 V/cm), reducing run times by up to 3-fold. The most striking improvements were observed with small DNAs and RNAs (10-100 bp): high voltages and short run times produced sharper bands and higher resolution. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Ionic liquid based multifunctional double network gel

    Science.gov (United States)

    Ahmed, Kumkum; Higashihara, Tomoya; Arafune, Hiroyuki; Kamijo, Toshio; Morinaga, Takashi; Sato, Takaya; Furukawa, Hidemitsu

    2015-04-01

    Gels are a promising class of soft and wet materials with diverse application in tissue engineering and bio-medical purpose. In order to accelerate the development of gels, it is required to synthesize multi-functional gels of high mechanical strength, ultra low surface friction and suitable elastic modulus with a variety of methods and new materials. Among many types of gel ionic gel made from ionic liquids (ILs) could be used for diverse applications in electrochemical devices and in the field of tribology. IL, a promising materials for lubrication, is a salt with a melting point lower than 100 °C. As a lubricant, ILs are characterized by an extremely low vapor pressure, high thermal stability and high ion conductivity. In this work a novel approach of making double network DN ionic gel using IL has been made utilizing photo polymerization process. A hydrophobic monomer Methyl methacrylate (MMA) has been used as a first network and a hydrophobic IL monomer, N,N-diethyl-N-(2-mthacryloylethyl)-N-methylammonium bistrifluoromethylsulfonyl)imide (DEMM-TFSI) has been used as a second network using photo initiator benzophenon and crosslinker triethylene glycol dimethacrylate (TEGDMA). The resulting DN ionic gel shows transparency, flexibility, high thermal stability, good mechanical toughness and low friction coefficient value which can be a potential candidate as a gel slider in different mechanical devices and can open a new area in the field of gel tribology.

  10. Gels and gel-derived glasses in the Na2O-B2O3-SiO2 system. [containerless melting in space

    Science.gov (United States)

    Mukherjee, S. P.

    1982-01-01

    The containerless melting of high-purity multicomponent homogeneous gels and gel-monoliths offers a unique approach to making ultrapure multicomponent optical glasses in the reduced gravity environment of space. Procedures for preparing and characterizing gels and gel-derived glasses in the Na2O-B2O3-SiO2 system are described. Preparation is based on the polymerization reactions of alkoxysilane with trimethyl borate or boric acid and a suitable sodium compound. The chemistry of the gelling process is discussed in terms of process parameters and the gel compositions. The physicochemical nature of gels prepared by three different procedures were found to be significantly different. IR absorption spectra indicate finite differences in the molecular structures of the different gels. The melting of the gel powders and the transformation of porous gel-monoliths to transparent 'glass' without melting are described.

  11. Improving calibration accuracy in gel dosimetry

    International Nuclear Information System (INIS)

    Oldham, M.; McJury, M.; Webb, S.; Baustert, I.B.; Leach, M.O.

    1998-01-01

    A new method of calibrating gel dosimeters (applicable to both Fricke and polyacrylamide gels) is presented which has intrinsically higher accuracy than current methods, and requires less gel. Two test-tubes of gel (inner diameter 2.5 cm, length 20 cm) are irradiated separately with a 10x10cm 2 field end-on in a water bath, such that the characteristic depth-dose curve is recorded in the gel. The calibration is then determined by fitting the depth-dose measured in water, against the measured change in relaxivity with depth in the gel. Increased accuracy is achieved in this simple depth-dose geometry by averaging the relaxivity at each depth. A large number of calibration data points, each with relatively high accuracy, are obtained. Calibration data over the full range of dose (1.6-10 Gy) is obtained by irradiating one test-tube to 10 Gy at dose maximum (D max ), and the other to 4.5 Gy at D max . The new calibration method is compared with a 'standard method' where five identical test-tubes of gel were irradiated to different known doses between 2 and 10 Gy. The percentage uncertainties in the slope and intercept of the calibration fit are found to be lower with the new method by a factor of about 4 and 10 respectively, when compared with the standard method and with published values. The gel was found to respond linearly within the error bars up to doses of 7 Gy, with a slope of 0.233±0.001 s -1 Gy -1 and an intercept of 1.106±0.005 Gy. For higher doses, nonlinear behaviour was observed. (author)

  12. Pharmacokinetics of 2 dapivirine vaginal microbicide gels and their safety vs. Hydroxyethyl cellulose-based universal placebo gel.

    Science.gov (United States)

    Nel, Annalene M; Smythe, Shanique C; Habibi, Sepideh; Kaptur, Paulina E; Romano, Joseph W

    2010-10-01

    Dapivirine, a nonnucleoside reverse transcriptase inhibitor, is in development as a microbicide for the protection of women against HIV infection. A randomized, double-blind, phase 1 trial was conducted in 36 healthy HIV-negative women to compare the pharmacokinetics of 2 dapivirine vaginal gel formulations (0.05% each) and their safety with the hydroxyethyl cellulose-based universal placebo gel. Gel was self-administered once daily for a total of 11 days. Blood and vaginal fluid samples were collected sequentially over 24 days for pharmacokinetic analysis. Safety was evaluated by pelvic examination, colposcopy, adverse events, and clinical laboratory assessments. Adverse event profiles were similar for the 3 gels. Most events were mild and not related to study gel. Headache and vaginal hemorrhage (any vaginal bleeding) were most common. Plasma concentrations of dapivirine did not exceed 1.1 ng/mL. Steady-state conditions were reached within approximately 10 days. Dapivirine concentrations in vaginal fluids were slightly higher for Gel 4789, but Cmax values on days 1 and 14 were not significantly different. Terminal half-life was 72-73 hours in plasma and 15-17 hours in vaginal fluids. Both formulations of dapivirine gel were safe and well tolerated. Dapivirine was delivered to the lower genital tract at concentrations at least 5 logs greater than in vitro inhibitory concentrations.

  13. Structural studies of gels and gel-glasses in the SiO2-GeO2 system using vibrational spectroscopy

    Science.gov (United States)

    Mukherjee, Shyama P.; Sharma, Shiv K.

    1986-01-01

    GeO2 gel and gels in the SiO2-GeO2 system synthesized by the hydrolytic polycondensation of metal alkoxides have been studied by infrared and Raman spectroscopic techniques. The molecular structures, hydroxyl contents, and crystallinity of gels and gel-glasses in relation to the thermal history and GeO2 concentration were investigated. The binary compositions having up to 70 mol percent GeO2 were examined.

  14. NMR mechanisms in gel dosimetry

    International Nuclear Information System (INIS)

    Schreiner, L J

    2009-01-01

    Nuclear magnetic resonance was critical to the development of gel dosimetry, as it established the potential for three dimensional dosimetry with chemical dosimeter systems through magnetic resonance imaging [1]. In the last two decades MRI has served as the gold standard for imaging, while NMR relaxometry has played an important role in the development and understanding of the behaviour of new gel dosimetry systems. Therefore, an appreciation of the relaxation mechanisms determining the NMR behaviour of irradiated gel dosimeters is important for a full comprehension of a considerable component of the literature on gel dosimetry. A number of excellent papers have presented this important theory, this brief review will highlight some of the salient points made previously [1-5]. The spin relaxation of gel dosimeters (which determines the dose dependence in most conventional MR imaging) is determined principally by the protons on water molecules in the system. These water protons exist in different environments, or groups (see Figure 1): on bulk water, on water hydrating the chemical species that are being modified under irradiation, and on water hydrating the gel matrix used to spatially stabilize the dosimeter (e.g., gelatin, agarose, etc). The spin relaxation depends on the inherent relaxation rate of each spin group, that is, on the relaxation rate which would be observed for the specific group if it were isolated. Also, the different water environments are not isolated from each other, and the observed relaxation rate also depends on the rate of exchange of magnetization between the groups, and on the fraction of protons in each group. In fact, the water exchanges quickly between the environments, so that relaxation is in what is usually termed the fast exchange regime. In the limit of fast exchange, the relaxation of the water protons is well characterized by a single exponential and hence by a single apparent relaxation rate. In irradiated gel dosimeters this

  15. Conducting polymer electrodes for gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Katarina Bengtsson

    Full Text Available In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene (PEDOT can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  16. Conducting polymer electrodes for gel electrophoresis.

    Science.gov (United States)

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that π-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

  17. Phosphorylation of DegU is essential for activation of amyE ...

    Indian Academy of Sciences (India)

    Gel filtration chromatography of DegU on Sephacryl. S100 (Methods). The native molecular weight of DegU was determined on a pre-calibrated Sephacryl S-100 ... Transferrin (80kDa), Alcohol Dehydrogenase (150 kDa). All the above markers were loaded individually. Purified DegU. (~1 mg), in a total volume of 1 mL was ...

  18. Sol-gel process for thermal reactor fuel fabrication

    International Nuclear Information System (INIS)

    Mukerjee, S.K.

    2008-01-01

    Full text: Sol-gel processes have revolutionized conventional ceramic technology by providing extremely fine and uniform powders for the fabrication of ceramics. The use of this technology for nuclear fuel fabrication has also been explored in many countries. Unlike the conventional sol-gel process, sol-gel process for nuclear fuels tries to eliminate the preparation of powders in view of the toxic nature of the powders particularly those of plutonium and 233 U. The elimination of powder handling thus makes this process more readily amenable for use in glove boxes or for remote handling. In this process, the first step is the preparation of microspheres of the fuel material from a solution which is then followed by vibro-compaction of these microspheres of different sizes to obtain the required smear density of fuel inside a pin. The maximum achievable packing density of 92 % makes it suitable for fast reactors only. With a view to extend the applicability of sol-gel process for thermal reactor fuel fabrication the concept of converting the gel microspheres derived from sol-gel process, to the pellets, has been under investigation for several years. The unique feature of this process is that it combines the advantages of sol-gel process for the preparation of fuel oxide gel microspheres of reproducible quality with proven irradiation behavior of the pellet fuel. One of the important pre-requisite for the success of this process is the preparation of soft oxide gel microspheres suitable for conversion to dense pellets free from berry structure. Studies on the internal gelation process, one of the many variants of sol-gel process, for obtaining soft oxide gel microspheres suitable for gel pelletisation is now under investigation at BARC. Some of the recent findings related to Sol-Gel Microsphere Pelletisation (SGMP) in urania-plutonia and thoria-urania systems will be presented

  19. Stabilized aqueous gels and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, B.L.

    1978-08-29

    New improved aqueous gels, and methods of using same in contacting subterranean formations, are provided. The gels are prepared by gelling an aqueous brine having incorporated therein a water-soluble cellulose ether such as a carboxymethylcellulose (CMC), and are rendered more stable to decomposition by incorporating a sulfoalkylated tannin stabilizing agent, such as a sulfomethylated quebracho (SMQ), in the gel during the preparation thereof.

  20. Influence of colloidal silicon dioxide on gel strength, robustness, and adhesive properties of diclofenac gel formulation for topical application.

    Science.gov (United States)

    Lu, Zheng; Fassihi, Reza

    2015-06-01

    The objective of this study is to identify the extent of stiffness, adhesiveness, and thixotropic character of a three-dimensional gel network of a 1% diclofenac sodium topical gel formulation in the presence and absence of colloidal silicon dioxide (CSD) and assess its ease of application and adhesiveness using both objective and subjective analysis. The 1% diclofenac gel was mixed with different amounts of CSD (e.g., 0.5, 1, 2, 3, and 5% w/w) and allowed to equilibrate prior to testing. The texture analyzer in combination with a cone-cap assembly was used to objectively investigate the changes in spreadability and adhesiveness of the gel system before and after addition of CSD. Results indicate that an increase in pliability and adhesiveness at levels ≥2 to ≤5% w/w of CSD dispersed in the gel ensues. For subjective analysis, gels with (2% w/w) CSD and in the absence of CSD were uniformly applied to a 20-cm(2) (5 cm × 4 cm) surface area on the forearms of healthy volunteers and vehicle preferences by the volunteers regarding ease of application, durability on the skin, compliance, and feelings concerning its textural properties were assessed. It appears that changes in the gel formulation with the addition of CSD enhance gel viscosity and bonding to the skin. Results further show that changes in physical and rheological characteristics of gel containing 2% w/w CSD did not significantly change subject preferences for the gel preparations. These findings may help formulators to have additional options to develop more robust and cost-effective formulations.

  1. SAXS study of silica sols, gels and glasses obtained by the sol gel process

    International Nuclear Information System (INIS)

    Santos, D.I. dos; Aegerter, M.A.

    1988-01-01

    Systematic SAXS studies have been performed at the LURE Synchrotron, Orsay, using an intense beam of point like cross-section to obtain information about the sol -> humid gel -> dried gel -> silica glass transformation. The intensity curves have been analysed in term of power law in log-log plots, whose exponent is related to mass and surface fractal dimensions of the structure. It was found that almost all phases present fractal structures and for the case of basic gels, is of hierarchical nature. The aerogels are formed by a dense matrix, with a smooth surface and exhibit a very narrow auto-similarity range that gives a mass fractal dimension. (author) [pt

  2. Effects of gel composition on the radiation induced density change in PAG polymer gel dosimeters: a model and experimental investigations

    International Nuclear Information System (INIS)

    Hilts, M; Jirasek, A; Duzenli, C

    2004-01-01

    Due to a density change that occurs in irradiated polyacrylamide gel (PAG), x-ray computed tomography (CT) has emerged as a feasible method of performing polymer gel dosimetry. However, applicability of the technique is currently limited by low sensitivity of the density change to dose. This work investigates the effect of PAG composition on the radiation induced density change and provides direction for future work in improving the sensitivity of CT polymer gel dosimetry. A model is developed that describes the PAG density change (Δρ gel ) as a function of both polymer yield (%P) and an intrinsic density change, per unit polymer yield, that occurs on conversion of monomer to polymer (Δρ polymer ). %P is a function of the fraction of monomer consumed and the weight fraction of monomer in the unirradiated gel (%T). Applying the model to experimental CT and Raman spectroscopic data, two important fundamental properties of the response of PAG density to dose (Δρ gel dose response) are discovered. The first property is that Δρ polymer depends on PAG %C (cross-linking fraction of total monomer) such that low and high %C PAGs exhibit a higher Δρ polymer than do more intermediate %C PAGs. This relationship is opposite to the relationship of polymer yield to %C and is explained by the effect of %C on the type of polymer formed. The second property is that the Δρ gel dose response is linearly dependent on %T. From the model, the inference is that, at least for %T≤12%, monomer consumption and Δρ polymer depend solely on %C. In terms of optimizing CT polymer gel dosimetry for high sensitivity, these results indicate that Δρ polymer can be expected to vary with each polymer gel system and thus should be considered when choosing a polymer gel for CT gel dosimetry. However, Δρ polymer and %P cannot be maximized simultaneously and maximizing %P, by choosing gels with intermediate %C and high %T, is found to have the greatest impact on increasing the

  3. Multi-gel casting apparatus for vertical polyacrylamide gels with in-built solution flow system and liquid level detectors.

    Science.gov (United States)

    Maurye, Praveen; Basu, Arpita; Bandyopadhyay, Tapas Kumar; Biswas, Jayanta Kumar; Mohanty, Bimal Prasana

    2017-08-01

    PAGE is the most widely used technique for the separation and biochemical analysis of biomolecules. The ever growing field of proteomics and genomics necessitates the analysis of many proteins and nucleic acid samples to understand further about the structure and function of cells. Simultaneous analysis of multiple protein samples often requires casting of many PAGE gels. Several variants of multi-gel casting/electrophoresis apparatuses are frequently used in research laboratories. Requirement of supplementary gels to match the growing demand for analyzing additional protein samples sometimes become a cause of concern. Available apparatuses are not amenable to and therefore, not recommended for any modification to accommodate additional gel casting units other than what is prescribed by the manufacturer. A novel apparatus is described here for casting multiple PAGE gels comprising four detachable components that provide enhanced practicability and performance of the apparatus. This newly modified apparatus promises to be a reliable source for making multiple gels in less time without hassle. Synchronized functioning of unique components broaden the possibilities of developing inexpensive, safe, and time-saving multi-gel casting apparatus. This apparatus can be easily fabricated and modified to accommodate desired number of gel casting units. The estimated cost (∼$300) for fabrication of the main apparatus is very competitive and effortless assembly procedure can be completed within ∼30 min. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Fluoride Rinses, Gels and Foams

    DEFF Research Database (Denmark)

    Twetman, Svante; Keller, Mette K

    2016-01-01

    AIM: The aim of this conference paper was to systematically review the quality of evidence and summarize the findings of clinical trials published after 2002 using fluoride mouth rinses, fluoride gels or foams for the prevention of dental caries. METHODS: Relevant papers were selected after...... (6 on fluoride mouth rinse, 10 on fluoride gel and 3 on fluoride foam); 6 had a low risk of bias while 2 had a moderate risk. All fluoride measures appeared to be beneficial in preventing crown caries and reversing root caries, but the quality of evidence was graded as low for fluoride mouth rinse......, moderate for fluoride gel and very low for acidulated fluoride foam. No conclusions could be drawn on the cost-effectiveness. CONCLUSIONS: This review, covering the recent decade, has further substantiated the evidence for a caries-preventive effect of fluoride mouth rinse, fluoride gel and foam...

  5. Aging and nonlinear rheology of thermoreversible colloidal gels

    Science.gov (United States)

    Wagner, Norman; Gordon, Melissa; Kloxin, Christopher

    Colloidal dispersions are found in a wide variety of consumer products such as paint, food and pharmaceuticals. We investigate gel formation and aging in a thermoreverible gel consisting of octadecyl-coated silica nanoparticles suspended in n-tetradecane. In this system, the octadecyl brush can undergo a phase change allowing the attractions between particles to be tuned by temperature (1,2). By probing the system with steady shear and large amplitude oscillatory shear, we have studied the effect of thermal history and shear history on gel formation and gel mechanical properties during aging. Gels were formed by approaching a common temperature from above and below to determine a reference state from which creep tests were conducted. Creep ringing was observed as expected for the viscoelastic gel. The rheological aging is interpreted in terms of the gel microstructure formed with differing thermal and shear histories to determine how processing affects structure. Recently proposed scaling laws for the rheology and structure under flow are explored within the context of gel aging (3). Through rheological and microstructural measurements, we will further the understanding of gel formation and aging in this model system which may be applied to processing conditions in an industrial setting.

  6. Mucosal effects of tenofovir 1% gel.

    Science.gov (United States)

    Hladik, Florian; Burgener, Adam; Ballweber, Lamar; Gottardo, Raphael; Vojtech, Lucia; Fourati, Slim; Dai, James Y; Cameron, Mark J; Strobl, Johanna; Hughes, Sean M; Hoesley, Craig; Andrew, Philip; Johnson, Sherri; Piper, Jeanna; Friend, David R; Ball, T Blake; Cranston, Ross D; Mayer, Kenneth H; McElrath, M Juliana; McGowan, Ian

    2015-02-03

    Tenofovir gel is being evaluated for vaginal and rectal pre-exposure prophylaxis against HIV transmission. Because this is a new prevention strategy, we broadly assessed its effects on the mucosa. In MTN-007, a phase-1, randomized, double-blinded rectal microbicide trial, we used systems genomics/proteomics to determine the effect of tenofovir 1% gel, nonoxynol-9 2% gel, placebo gel or no treatment on rectal biopsies (15 subjects/arm). We also treated primary vaginal epithelial cells from four healthy women with tenofovir in vitro. After seven days of administration, tenofovir 1% gel had broad-ranging effects on the rectal mucosa, which were more pronounced than, but different from, those of the detergent nonoxynol-9. Tenofovir suppressed anti-inflammatory mediators, increased T cell densities, caused mitochondrial dysfunction, altered regulatory pathways of cell differentiation and survival, and stimulated epithelial cell proliferation. The breadth of mucosal changes induced by tenofovir indicates that its safety over longer-term topical use should be carefully monitored.

  7. On shear rheology of gel propellants

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Shai; Peretz, Arie [RAFAEL, MANOR Propulsion and Explosive Systems Division, Haifa (Israel); Natan, Benveniste [Faculty of Aerospace Engineering, Technion - Israel Institute of Technology, Haifa (Israel)

    2007-04-15

    Selected fuel, oxidizer and simulant gels were prepared and rheologically characterized using a rotational rheometer. For fuel gelation both organic and inorganic gellants were utilized, whereas oxidizers and simulants were gelled with addition of silica and polysaccharides, respectively. The generalized Herschel-Bulkley constitutive model was found to most adequately represent the gels studied. Hydrazine-based fuels, gelled with polysaccharides, were characterized as shear-thinning pseudoplastic fluids with low shear yield stress, whereas inhibited red-fuming nitric acid (IRFNA) and hydrogen peroxide oxidizers, gelled with silica, were characterized as yield thixotropic fluids with significant shear yield stress. Creep tests were conducted on two rheological types of gels with different gellant content and the results were fitted by Burgers-Kelvin viscoelastic constitutive model. The effect of temperature on the rheological properties of gel propellant simulants was also investigated. A general rheological classification of gel propellants and simulants is proposed. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  8. Thixotropic corrosive gels for nuclear decontamination

    International Nuclear Information System (INIS)

    Bargues, St.

    1998-01-01

    The aim of this thesis was the development of corrosive gels for metallic surface decontamination. These gels formulation, based on a powerful oxidant (the cerium IV), the nitric acid, a mineral charge (silica) and a non ionic surface-active, has been developed according to the specific constraints of the nuclear industry. The objective was to prepare thixotropic gels becoming liquid after shacking to allow an easy pulverization and coming again solid to permit a perfect adhesion on the metallic surface. This rheological study of the gels has been completed by an evaluation of their corrosive properties. The last part of the work presents an industrial utilization during two years. (A.L.B.)

  9. Structure of gels layers with cells

    Science.gov (United States)

    Pokusaev, B. G.; Karlov, S. P.; Vyazmin, A. V.; Nekrasov, D. A.; Zakharov, N. S.; Khramtsov, D. P.; Skladnev, D. A.; Tyupa, D. V.

    2017-11-01

    The structure of two-layer agarose gels containing yeast cells is investigated experimentally by spectrometry, to shed a light on the theoretical foundations for the development of bioreactors by the method of 3D bioprinting. Due to division, cells overcome the layer of the dispersion phase separating successively applied layers of the agarose gel. However a gel layer of 100 μm thick with a high concentration of silver nanoparticles completely excludes the infiltration of yeast cells through it. A special sort of agarose is suggested where the concentration of silver nanoparticles formed by cells from salt of silver can serve as an indicator of the state of the yeast cells in the volume of the gel.

  10. Amy Winehouse e a casa dos mortos: a noção de genialidade no Romantismo Alemão DOI - 10.5752/P.2358-3428.2012v16n31p97

    Directory of Open Access Journals (Sweden)

    Sérgio Murilo Rodrigues

    2012-12-01

    Full Text Available  Criar significa destruir também. A genialidade cobra um preço alto: a angústia, a vida dilacerada. A chama que ilumina mais, dura menos. Amy Winehouse não foi a primeira e provavelmente não será a última artista genial a entrar em um processo autodestrutivo. Um processo de total perda de esperança resultando na busca deliberada pela morte. No Romantismo Alemão vários escritores e filósofos falaram sobre o peso da genialidade. Schelling coloca que o gênio é capaz da mesma intuição criadora do Espírito Absoluto. Schopenhauer nos fala da dor de ser gênio. Nietzsche, como Schiller, defende a genialidade artística como o único objetivo digno da vida humana. A vida é arte e cabe a nós desenvolvermos essa arte. Os poetas malditos, as estrelas do rock e do jazz celebraram esta festa, a vida, mesmo que, ao final, não haja mais vida alguma. Diante de um fenômeno midiático como Amy Winehouse, como podemos compreender toda essa reflexão filosófica sobre arte, vida, genialidade e morte?  Palvras-chave: Filosofia. Amy Winehouse. Genialidade. Romantismo Alemão.

  11. Modelling of the inhomogeneous interior of polymer gels

    International Nuclear Information System (INIS)

    Shew, C-Y; Iwaki, Takafumi

    2006-01-01

    A simple model has been investigated to elucidate the mean squared displacement (MSD) of probe molecules in cross-linked polymer gels. In the model, we assume that numerous cavities distribute in the inhomogeneous interior of a gel, and probe molecules are confined within these cavities. The individual probe molecules trapped in a gel are treated as Brownian particles confined to a spherical harmonic potential. The harmonic potential is chosen to model the effective potential experienced by the probe particle in the cavity of a gel. Each field strength is corresponding to the characteristic of one type of effective cavity. Since the statistical distribution of different effective cavity sizes is unknown, several distribution functions are examined. Meanwhile, the calculated averaged MSDs are compared to the experimental data by Nisato et al (2000 Phys. Rev. E 61 2879). We find that the theoretical results of the MSD are sensitive to the shape of the distribution function. For low cross-linked gels, the best fit is obtained when the interior cavities of a gel follow a bimodal distribution. Such a result may be attributed to the presence of at least two distinct classes of cavity in gels. For high cross-linked gels, the cavities in the gel can be depicted by a single-modal uniform distribution function, suggesting that the range of cavity sizes becomes smaller. These results manifest the voids inside a gel, and the shape of distribution functions may provide the insight into the inhomogeneous interior of a gel

  12. Actuator device utilizing a conductive polymer gel

    Science.gov (United States)

    Chinn, Douglas A.; Irvin, David J.

    2004-02-03

    A valve actuator based on a conductive polymer gel is disclosed. A nonconductive housing is provided having two separate chambers separated by a porous frit. The conductive polymer is held in one chamber and an electrolyte solution, used as a source of charged ions, is held in the second chamber. The ends of the housing a sealed with a flexible elastomer. The polymer gel is further provide with electrodes with which to apply an electrical potential across the gel in order to initiate an oxidation reaction which in turn drives anions across the porous frit and into the polymer gel, swelling the volume of the gel and simultaneously contracting the volume of the electrolyte solution. Because the two end chambers are sealed the flexible elastomer expands or contracts with the chamber volume change. By manipulating the potential across the gel the motion of the elastomer can be controlled to act as a "gate" to open or close a fluid channel and thereby control flow through that channel.

  13. Modelling of erosion of bentonite gel by gel/sol flow

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Luis; Neretnieks, Ivars; Longcheng Liu (Chemical Engineering and Technology, School of Chemical Science and Engineering, Royal Institute of Technology, Stockholm (Sweden))

    2010-11-15

    Bentonite intrusion into a fracture intersecting the canister deposition hole is modelled. The model describes the expansion of the bentonite within the fracture. It accounts for the repulsive electrostatic double-layer forces, the attractive van der Waals forces and friction forces between the particles and the water. The model also takes into account the diffusion of the colloid particles in the smectite sol. Diffusion of a counterion, sodium, is accounted for as this strongly influences the double layer force and the viscosity of the gel/sol. The gel/sol is considered to be a fluid with a varying viscosity that is strongly dependent on the bentonite volume fraction in the gel and the sodium concentration in the water. Two different geometries were modelled; a rectangular and a cylindrical. The rectangular geometry was used to gain experience with the processes and mechanisms and how they interact since the cylindrical geometry was somewhat less stable numerically and more time consuming. In the rectangular geometry a fracture 1 metre long in the flow direction was modelled. In both geometries the fracture size was selected sufficiently large to ensure that the water velocity, near the distant border was nearly the same as the approaching water velocity and that the smectite concentration there was vanishingly small. It was found that the velocity of the fluid drops considerably where the bentonite volume fraction is larger than 1-2%. This is due to the strong increase in viscosity with increasing bentonite volume fraction. The loss of smectite by the slowly flowing fluid was found to be proportional to the square root of the seeping water velocity for the rectangular geometry. For the cylindrical geometry, the dependence is somewhat lower (exponent about 0.4) since the length of the gel/water interface decreases with increasing water flow rate. The penetration depth of the gel/water interface decreases with increasing water flow rate. For water velocity of the

  14. Modelling of erosion of bentonite gel by gel/sol flow

    International Nuclear Information System (INIS)

    Moreno, Luis; Neretnieks, Ivars; Longcheng Liu

    2010-11-01

    Bentonite intrusion into a fracture intersecting the canister deposition hole is modelled. The model describes the expansion of the bentonite within the fracture. It accounts for the repulsive electrostatic double-layer forces, the attractive van der Waals forces and friction forces between the particles and the water. The model also takes into account the diffusion of the colloid particles in the smectite sol. Diffusion of a counterion, sodium, is accounted for as this strongly influences the double layer force and the viscosity of the gel/sol. The gel/sol is considered to be a fluid with a varying viscosity that is strongly dependent on the bentonite volume fraction in the gel and the sodium concentration in the water. Two different geometries were modelled; a rectangular and a cylindrical. The rectangular geometry was used to gain experience with the processes and mechanisms and how they interact since the cylindrical geometry was somewhat less stable numerically and more time consuming. In the rectangular geometry a fracture 1 metre long in the flow direction was modelled. In both geometries the fracture size was selected sufficiently large to ensure that the water velocity, near the distant border was nearly the same as the approaching water velocity and that the smectite concentration there was vanishingly small. It was found that the velocity of the fluid drops considerably where the bentonite volume fraction is larger than 1-2%. This is due to the strong increase in viscosity with increasing bentonite volume fraction. The loss of smectite by the slowly flowing fluid was found to be proportional to the square root of the seeping water velocity for the rectangular geometry. For the cylindrical geometry, the dependence is somewhat lower (exponent about 0.4) since the length of the gel/water interface decreases with increasing water flow rate. The penetration depth of the gel/water interface decreases with increasing water flow rate. For water velocity of the

  15. Dosimetry Evolution in Teletherapy: Polimer Gel

    Science.gov (United States)

    Hamann, J. H.; Peixoto, J. G. P.

    2018-03-01

    Polymer gels evolution and chemical composition used in dosimetry. Type Composition First gels Folin’s Phenol or Gallic Acid Polymer Gel Agarose and N,N’-methylene-bis-acrylamide BANANA Bis, acrylamide, nitrous oxide and agarose BANG-1TM Bis, acrylamide, nitrogen and gelatin BANG-2TM Bis, acrylic acid, sodium hydroxide, nitrogen and gelatin BANG-3TM Bis, methacrylate acid, sodium hydroxide, nitrogen and gelatin MAGIC Methacrylate acid, ascorbic acid, gelatin and copper sulphate

  16. Optimized Benzalkonium Chloride Gel: A Potential Vaginal Microbicides

    Institute of Scientific and Technical Information of China (English)

    Xun-cheng DING; Wei-hua LI; Jie-fei LI; Qiang-yi WANG

    2007-01-01

    Objective To develop an optimized BZK gel with good pharmaceutical effect and less toxicity to vaginal mucosa.Methods Four methods as below were used to research the spermicidal activity of BZK gel: 1)in vitro spermicidal test; 2) in vivo spermicidal test in rabbits; 3) anti-fertility test in rabbits; 4)contraceptive test in rabbits. Mucosal irritation test was used in rats to evaluate the safety of optimized BZK gel. Microbiological assessments were used to research anti-STI pathogens (including treponema pallidum, neisseria gonorrhoeae, trichomona vaginalis, candida albicans,ureaplama urealyticum, herpes simplex virus type-2, chlamydiae trachomatis) effect of optimized BZK gel.Results In vitro spermicidal test, EC50 of BZK gel was 0.029 mg/ml, a little higher than that of N-9 (0.019 mg/ml). The MIC of BZK gel was 0.25 mg/ml, similar to that of N-9 (0.20 mg/ml).The vaginal mucosal irritation test in rats showed that 0.429% BZK gel showed only minimal vaginal irritation, and did not damage the vaginal epithelium or cause local inflammation in rats. Microbiological assessments showed that optimized BZK gel could inhibit or inactivate common STI pathogens even after 3-fold or 5-fold dilution.Conclusion Optimized BZK gel was an effective microbicides.

  17. Oh and by the way, you get meter readings too : a look at distribution automation, intelligent grids, and demand side management : getting the real value from your AMI

    Energy Technology Data Exchange (ETDEWEB)

    Summerlin, T. [Gestalt, Camden, NJ (United States); Ferguson, P.D. [Newmarket Hydro Ltd., Newmarket, ON (Canada)

    2006-07-01

    The full value of smart metering programs will be realized when information and communication capabilities are used to enable distribution automation, intelligent grids, and sufficient data management that will transform interval meter data into useful information. By leveraging and managing meter data effectively, utilities can increase their operational efficiency, improve their understanding of customers' needs, and develop more effective demand side management programs. This presentation examined some of the changing priorities of advanced metering infrastructure (AMI) strategies, and provided details of meter data management (MDM) technologies developed to help utilities increase efficiency, cut costs and provide better service to their customers. An MDM system is the set of data bases and applications required to provide utilities with a solution for the data retention, analysis and storage repository gaps that will be created when monthly manual meter readings are replaced with AMI systems. In order to resolve storage, functionality and legacy integration gaps, MDM systems must be scalable systems that can support large and small quantities of meter data, and must also conform to industry standard data warehouse designs. Data structure in the systems must support both regulated and deregulated markets, and be capable of providing extensive graphical, tabular and Excel export of the metered and totalized data from the interval to system level. MDM systems can provide improved support for demand response decision-making processes; distribution planning and reliability; outage management; revenue assurance; forecasting; and curtailment. It was concluded that MDM systems can be used to improve processes and provide additional benefits well beyond the meter reading and billing process benefits originally identified by utilities as a primary goal of implementing AMI. refs., tabs., figs.

  18. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  19. Preparation of zirconium molybdate gel generator

    International Nuclear Information System (INIS)

    Charoen, S.; Aungurarat, G.; Laohawilai, S.; Sukontpradit, W.; Jingjit, S.

    1994-01-01

    A procedure for preparation of 99mTc generator based on conversion to zirconium molybdate gel of 99Mo produced by neutron activation was reported. The gel was prepared from zirconium oxychloride solution pH 1.6, ammonium molybdate solution pH 3-5 and mole ratio of Zr:Mo 1:1 which had water content about 7-8%. Small generators containing 1-1.5 g of gel were eluted with average efficiencies of 77% and the activity peak in the first 3 ml of 10 ml of saline solution. The amount of Mo and Zr in eluates were below the acceptance limit. The gel generators of activity about 100 mCi were prepared and had the good performance in elutability and stability

  20. Radiotherapy gel dosimetry

    International Nuclear Information System (INIS)

    Baldock, C.

    2002-01-01

    shapes and sizes while sparing normal tissue. The situation is further complicated if the normal tissues are critical organs or are particularly sensitive to radiation. Radiotherapy techniques employed to obtain a closer conformation of the dose distribution to the tumour volume are referred to as conformal radiotherapy techniques. The clinical implementation of conformal therapy has been delayed by limitations in the verification of conformal dose distributions calculated by treatment planning systems prior to the irradiation of the patient and the verification of complex treatments during its delivery to the patient. There are several aspects of conformal therapy that complicate dose verification. To achieve the dose distributions conforming to complex 3D volumes, high dose gradients arise in the treatment volume. Further, overdose or underdose regions can exist when separate radiation fields are used to deliver additional radiation. These aspects require that practical dose measurement (dosimetry) techniques be able to integrate dose over time and easily measure dose distributions in 3D with high spatial resolution. Traditional dosimeters, such as ion chambers, thermoluminescent dosimeters and radiographic film do not fulfil these requirements. Novel gel dosimetry techniques are being developed in which dose distributions can potentially be determined in vitro in 3D using anthropomorphic phantoms to simulate a clinically irradiated situation. As long ago as the 1950's, radiation-induced colour change in dyes was used to investigate radiation doses in gels. It was subsequently shown that radiation induced changes in nuclear magnetic resonance (NMR) relaxation properties of gels infused with conventional Fricke dosimetry solutions could be measured using magnetic resonance imaging (MRI). In Fricke gels, Fe 2+ ions in ferrous sulphate solutions are usually dispersed throughout a gelatin, agarose or PVA matrix. Radiation-induced changes in the dosimeters are considered to

  1. Sol-gel preparation of uranium oxide spheres

    International Nuclear Information System (INIS)

    Dolezal, J.; Urbanek, V.

    1978-01-01

    Information is presented on problems of preparing nuclear fuel by the sol-gel method. Basic data on different process types are given. A more detailed description of the method of preparation of spherical particles of uranium oxide gel developed and used at the Nuclear Research Institute at Rez is given. Advantages and disadvantages of sol-gel materials are discussed in comparison with fuel materials prepared by classical precipitation methods. The feasibility of the sol-gel methods for preparing other materials is shortly mentioned and their application outlined. (author)

  2. Functional coatings: the sol-gel approach

    International Nuclear Information System (INIS)

    Belleville, Ph.

    2010-01-01

    CEA's sol-gel laboratory is specialized in the development of innovative sol-gel optical coatings and has extended its application field to membrane materials and coatings for energy conversion, to electric coatings for microelectronics devices and to thin films for gas sensing. This article describes, by way of examples, the laboratory's research on sol-gel functional coatings, including nano-material synthesis, organic-inorganic hybrid-based solution preparation as well as deposition process development and prototyping. (author)

  3. Positron annihilation lifetime studies of sol-gel transition of carrageenan gels

    International Nuclear Information System (INIS)

    Wakabayashi, Y.; Ito, K.; Li, H.L.; Ujihara, Y.

    1996-01-01

    Positron annihilation lifetime measurement was applied to study the sol-gel transition of anionic polysaccharide aqueous solutions in terms of free-volume parameters the size, intensity, and size distribution of free volumes of the gelation of K-form κ-carrageenan solutions as a function of temperature. Slight variations of free volume size and intensity against temperature were observed near 295 K. The correlation of free-volume data with other physical properties vibrational spectra (IR and Raman), conductivity, SAXS, elastic measurement, differential scanning calorimetry were investigated to understand the mechanism of sol-gel transition of carrageenan. (author)

  4. Sol-gel growth of vanadium dioxide

    International Nuclear Information System (INIS)

    Speck, K.R.

    1990-01-01

    This thesis examines the chemical reactivity of vanadium (IV) tetrakis(t-butoxide) as a precursor for the sol-gel synthesis of vanadium dioxide. Hydrolysis and condensation of the alkoxide was studied by FTIR spectroscopy. Chemical modification of the vanadium tetraalkoxide by alcohol interchange was studied using 51 V NMR and FTIR. Vanadium dioxide thin films and powders were made from vanadium tetrakis(t-butoxide) by standard sol-gel techniques. Post-deposition heating under nitrogen was necessary to transform amorphous gels into vanadium dioxide. Crystallization of films and powders was studied by FTIR, DSC, TGA, and XRD. Gel-derived vanadium dioxide films undergo a reversible semiconductor-to-metal phase transition near 68C, exhibiting characteristic resistive and spectral changes. The electrical resistance decreased by two to three orders of magnitude and the infrared transmission sharply dropped as the material was cycled through this thermally induced phase transition. The sol-gel method was also used to make doped vanadium dioxide films. Films were doped with tungsten and molybdenum ions to effectively lower the temperature at which the transition occurs

  5. The performance of gel technetium-99m generator

    International Nuclear Information System (INIS)

    Liu Yishu

    2004-01-01

    Technetium-99m, as one of the important radionuclides in nuclear medical science, has been widely used for diseases diagnosis in both developed and developing countries for many years. Technetium-99m can be obtained from both fission-type and gel-type Tc-99m generator. Fission-type generator was prepared by Molybdenum-99 separated from fission products of uranium-235 and gel-type was prepared by irradiating nature MoO 3 in reactor, and a series of chemical and physical processes. This paper briefly describes the manufacturing technical process of gel-type Technetium-99 generator, including the preparation of target containing nature MoO 3 , the target irradiation in reactor, gel preparation, gel filtration and drying, dried gel cracking, generator loading and activity calibration of generator. The performances of gel-type Technetium-99m generator, such as elution efficiency, elution profile, the pH, Mo breakthrough, Zirconium content, radiochemical purity, radionuclidic purity, sterility and pyrogencity of eluate, are also expatiated in detail. Comparing with fission-type Technetium-99m generator, the defects of gel-type Technetium-99m generator are enumerated and their overcoming solutions are recommended in this paper. (author)

  6. Pouring and running a protein gel by reusing commercial cassettes.

    Science.gov (United States)

    Hwang, Alexander C; Grey, Paris H; Cuddy, Katrina; Oppenheimer, David G

    2012-02-12

    The evaluation of proteins using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis is a common technique used by biochemistry and molecular biology researchers. For laboratories that perform daily analyses of proteins, the cost of commercially available polyacrylamide gels (~$10/gel) can be considerable over time. To mitigate this cost, some researchers prepare their own polyacrylamide gels. Traditional methods of pouring these gels typically utilize specialized equipment and glass gel plates that can be expensive and preclude pouring many gels and storing them for future use. Furthermore, handling of glass plates during cleaning or gel pouring can result in accidental breakage creating a safety hazard, which may preclude their use in undergraduate laboratory classes. Our protocol demonstrates how to pour multiple protein gels simultaneously by recycling Invitrogen Nupage Novex minigel cassettes, and inexpensive materials purchased at a home improvement store. This economical and streamlined method includes a way to store the gels at 4°C for a few weeks. By re-using the plastic gel cassettes from commercially available gels, labs that run frequent protein gels can save significant costs and help the environment. In addition, plastic gel cassettes are extremely resistant to breakage, which makes them ideal for undergraduate laboratory classrooms.

  7. The effects of brushing on human enamel surface roughness after NaF gel and theobromine gel exposure

    Science.gov (United States)

    Mahardhika, A.; Noerdin, A.; Eriwati, Y. K.

    2017-08-01

    This study aimed to determine the effects of brushing on human enamel surface roughness after different exposure times of 200 mg/L theobromine gel (8, 16, and 32 minutes) and 2% NaF gel (16 minutes). Twenty-four human upper premolars were used and divided into four groups. Group 1 was exposed to 2% NaF gel for 16 minutes. In contrast, groups 2, 3, and 4 were exposed to 200 mg/L theobromine gel for 8 minutes, 16 minutes, and 32 minutes, and each group was then brushed for 9 minutes and 20 seconds. After the treatment, samples were tested using a surface roughness tester (Mitutoyo SJ 301, Japan). The Wilcoxon test showed significant changes (p enamel surface and then increase roughness after brushing.

  8. Diasporic Authenticity Assertions: Analysis of Amy Tan’s The Bonesetter’s Daughter

    Directory of Open Access Journals (Sweden)

    Naeimeh Tabatabaei Lotfi

    2015-07-01

    Full Text Available This essay is an attempt to examine the active interaction of history and memory, in formulation of a diasporic authentic picture of past, in Amy Tan’s The Bonesetter’s Daughter (2001. Amongst discursive disciplines, memory and history perform vitally, in picturing past; both attempt to reproduce events, by emblematic narrative acts. However, their erratic quality endorses the existence of counter- stories that endangers displaying a homogeneous past. Among miscellaneous categories of memories, autobiographical memory asserts to obtain an authentic presentation, but as any other forms of accounts, it exhibits an imprecise fictional image. This psychological alleviation ensures the future mental integrity of trauma victims. In memory narratives, the contingent temperament of power network and continual formulation of resisting frameworks might be explored. Tan’s diasporic assertion of authenticity, as a migrant writer, amalgamated with employment of fantasy is to obtain a shared diasporic identity, among her characters, although personal accounts of characters undergo an extensive amount of contingency. The newly forged identity is collective in nature and defies the geographical and temporal borders and grants a humane picture rather than a diasporic one; an identity that is established to venerate the cardinal role of personal memory, in endowing legitimate truth.

  9. Off-line tracking of series parameters in distribution systems using AMI data

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tess L.; Sun, Yannan; Schneider, Kevin

    2016-05-01

    Electric distribution systems have historically lacked measurement points, and equipment is often operated to its failure point, resulting in customer outages. The widespread deployment of sensors at the distribution level is enabling observability. This paper presents an off-line parameter value tracking procedure that takes advantage of the increasing number of measurement devices being deployed at the distribution level to estimate changes in series impedance parameter values over time. The tracking of parameter values enables non-diurnal and non-seasonal change to be flagged for investigation. The presented method uses an unbalanced Distribution System State Estimation (DSSE) and a measurement residual-based parameter estimation procedure. Measurement residuals from multiple measurement snapshots are combined in order to increase the effective local redundancy and improve the robustness of the calculations in the presence of measurement noise. Data from devices on the primary distribution system and from customer meters, via an AMI system, form the input data set. Results of simulations on the IEEE 13-Node Test Feeder are presented to illustrate the proposed approach applied to changes in series impedance parameters. A 5% change in series resistance elements can be detected in the presence of 2% measurement error when combining less than 1 day of measurement snapshots into a single estimate.

  10. Pecan drying with silica gel

    Energy Technology Data Exchange (ETDEWEB)

    Ghate, S.R.; Chhinnan, M.S.

    1983-07-01

    High moisture in-shell pecans were dried by keeping them in direct and indirect contact with silica gel to investigate their drying characteristics. In-shell pecans were also dried with ambient air from a controlled environment chamber and with air dehumidified by silica gel. Direct contact and dehumidified air drying seemed feasible approaches.

  11. Gel chromatography of sup(99m)Tc-labelled compounds

    International Nuclear Information System (INIS)

    Vilcek, S.; Machan, V.; Kalincak, M.

    1976-01-01

    The present state of gel chromatography of sup(99m)Tc-labelled compounds is reviewed. Examples are given of gel chromatography for preparing labelled compounds and for quality control analysis and the development of new types of sup(99m)Tc-labelled compounds. The factors which influence the gel chromatography of these compounds are discussed, i.e., the nature of the elution agent, the duration of the contact of the gel and the preparation the gel type, the nature of the labelled compound. The GCS method (gel chromatography scanning) is briefly described. The advantages of gel chromatography as compared with other chromatographic techniques for sup(99m)Tc-labelled compounds are summarized. (author)

  12. 21 CFR 866.4900 - Support gel.

    Science.gov (United States)

    2010-04-01

    ... IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunology Laboratory Equipment and Reagents § 866.4900 Support gel. (a) Identification. A support gel for clinical use is a device that consists of an agar or agarose preparation that...

  13. Caffeine-catalyzed gels.

    Science.gov (United States)

    DiCiccio, Angela M; Lee, Young-Ah Lucy; Glettig, Dean L; Walton, Elizabeth S E; de la Serna, Eva L; Montgomery, Veronica A; Grant, Tyler M; Langer, Robert; Traverso, Giovanni

    2018-07-01

    Covalently cross-linked gels are utilized in a broad range of biomedical applications though their synthesis often compromises easy implementation. Cross-linking reactions commonly utilize catalysts or conditions that can damage biologics and sensitive compounds, producing materials that require extensive post processing to achieve acceptable biocompatibility. As an alternative, we report a batch synthesis platform to produce covalently cross-linked materials appropriate for direct biomedical application enabled by green chemistry and commonly available food grade ingredients. Using caffeine, a mild base, to catalyze anhydrous carboxylate ring-opening of diglycidyl-ether functionalized monomers with citric acid as a tri-functional crosslinking agent we introduce a novel poly(ester-ether) gel synthesis platform. We demonstrate that biocompatible Caffeine Catalyzed Gels (CCGs) exhibit dynamic physical, chemical, and mechanical properties, which can be tailored in shape, surface texture, solvent response, cargo release, shear and tensile strength, among other potential attributes. The demonstrated versatility, low cost and facile synthesis of these CCGs renders them appropriate for a broad range of customized engineering applications including drug delivery constructs, tissue engineering scaffolds, and medical devices. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Gel electrolytes and electrodes

    Science.gov (United States)

    Fleischmann, Sven; Bunte, Christine; Mikhaylik, Yuriy V.; Viner, Veronika G.

    2017-09-05

    Gel electrolytes, especially gel electrolytes for electrochemical cells, are generally described. In some embodiments, the gel electrolyte layers comprise components a) to c). Component a) may be at least one layer of at least one polymer comprising polymerized units of: a1) at least one monomer containing an ethylenically unsaturated unit and an amido group and a2) at least one crosslinker. Component b) may be at least one conducting salt and component c) may be at least one solvent. Electrodes may comprise the components a), d) and e), wherein component a) may be at least one layer of at least one polymer as described herein. Component d) may be at least one electroactive layer and component e) may be at least one ceramic layer. Furthermore, electrochemical cells comprising component a) which may be at least one layer of at least one polymer as described herein, are also provided.

  15. Detection of Aspartic Proteinase Activities Using Gel Zymography.

    Science.gov (United States)

    Perera, Handunge Kumudu Irani

    2017-01-01

    Gel zymography is a two-stage process where the proteins from the test sample are first separated by electrophoresis followed by the detection of the activity of hydrolytic enzymes. Many zymography procedures use sodium dodecyl sulfate (SDS) polyacrylamide gels copolymerized with an appropriate substrate. The procedure described here uses native polyacrylamide gel electrophoresis (PAGE) in the absence of both SDS and substrate. In order to visualize aspartic proteinase activity, the gel is impregnated in bovine hemoglobin at pH 3.0 for 15 min after the electrophoresis procedure. Subsequently, the gel is incubated in a humid container in the absence of hemoglobin for 1 h at 37 °C. At the end, the gel is stained with amido black and destained. Clear areas against a dark background corresponding to aspartic proteinase activities can be detected.

  16. Betwixt and Between Past and Present: Cultural and Generic Hybridity in the Fiction of Amy Tan and Mary Yukari Waters Rania Youssef

    OpenAIRE

    Rania Youssef

    2012-01-01

    Amy Tan and Mary Yukari Waters are both Asian-Americans who portray hybridity in their short stories which depict the shifting identities of the self. But do the internal categories of gender, race and ethnicity help in the coherence or do they add to the fragmentation of diverse identities? It is the dynamics of this critique of multiple identification and hybrid cultures that is being traced here in this study and how all this is reflected in narrative responses to such conditions of the ex...

  17. [Overdentures covering natural roots. The use of chlorhexidine gel].

    Science.gov (United States)

    Hendrikx, M J; Kramer, J E; de Baat, C

    2000-03-01

    To prevent caries and periodontal disease in overdenture abutment teeth, daily application of chlorhexidine gel is recommended. In order to get insight into the use of the gel, 29 overdenture wearing patients were interviewed. In addition the patients were requested to show the use of the gel. It was concluded that at any time the patients were instructed about the use of the gel. Nevertheless, a majority of the patients did not use the gel daily and in accordance with the instructions given. Application of the gel in the abutment depressions of the overdenture appeared to be a heavy task.

  18. Development of strippable gel for surface decontamination applications

    International Nuclear Information System (INIS)

    Banerjee, D.; Sandhya, U.; Khot, S.A.; Srinivas, C.

    2015-07-01

    Strippable gels are an attractive option for decontamination of surfaces particularly when materials are to be reused after decontamination. The process in general results in good decontamination performance with minimal secondary waste generation. This paper reports on development of strippable gel formulation using polyvinyl alcohol as the gel former. Peeling behavior of the gel film improved when glycerol was used as plasticizer. Incorporation of decontaminating agents is essential for the gel to be effective, so a number of decontaminating agents were screened based on their miscibility with the gel, smooth peeling, and good decontamination performance. Based on this study, a strippable gel, ‘INDIGEL’ was formulated as a potential candidate for surface decontamination applications. Extensive trials on evaluation of decontamination performance of Indigel were done on simulated surfaces like stainless steel tray, stainless steel fume hood, PVC floor, granite and ceramic table tops. Results show that Indigel is highly effective for decontamination of surfaces contaminated with all types of radionuclides. Simplicity of its use coupled with good decontamination ability will find application in nuclear and other chemical industries. (author)

  19. Method of making ionic liquid mediated sol-gel sorbents

    Science.gov (United States)

    Malik, Abdul; Shearrow, Anne M.

    2017-01-31

    Ionic liquid (IL)-mediated sol-gel hybrid organic-inorganic materials present enormous potential for effective use in analytical microextraction. One obstacle to materializing this prospect arises from high viscosity of ILs significantly slowing down sol-gel reactions. A method was developed which provides phosphonium-based, pyridinium-based, and imidazolium-based IL-mediated advanced sol-gel organic-inorganic hybrid materials for capillary microextraction. Scanning electron microscopy results demonstrate that ILs can serve as porogenic agents in sol-gel reactions. IL-mediated sol-gel coatings prepared with silanol-terminated polymers provided up to 28 times higher extractions compared to analogous sol-gel coatings prepared without any IL in the sol solution. This study shows that IL-generated porous morphology alone is not enough to provide effective extraction media: careful choice of the organic polymer and the precursor with close sol-gel reactivity must be made to ensure effective chemical bonding of the organic polymer to the created sol-gel material to be able to provide the desired sorbent characteristics.

  20. Élaboration d’indicateurs pour l’évaluation des collectivités-amies des aînés au Canada : démarche et résultats

    Directory of Open Access Journals (Sweden)

    H. Orpana

    2016-01-01

    Full Text Available Introduction : En 2006, l’Organisation mondiale de la Santé (OMS a lancé le projet mondial « Villes-amies des aînés » afin de favoriser un vieillissement actif. Si un grand nombre d’initiatives « amies des aînés » ont été mises en oeuvre au Canada, on dispose de peu d’information sur l’efficacité et les résultats des initiatives des collectivités-amies des aînés (CAA. En outre, les intervenants affirment qu’ils n’ont pas la capacité et les outils nécessaires pour élaborer et réaliser des évaluations relatives à leurs initiatives de CAA. Afin de pallier ces lacunes, l’Agence de la santé publique du Canada a mis au point des indicateurs pour l’évaluation des initiatives de CAA dans de nombreuses collectivités canadiennes. Ces indicateurs, destinés à répondre aux différents besoins des collectivités, ne sont pas conçus pour faire l’évaluation de répercussions collectives ou pour rendre possible une comparaison entre collectivités. Méthodologie : Une démarche de consultation itérative fondée sur des données probantes a été employée pour l’élaboration d’indicateurs relatifs aux CAA. Elle a nécessité une revue de la littérature et une analyse du contexte. Deux rondes de consultation auprès d’experts et d’intervenants clés ont été menées, ce qui a permis de classer les indicateurs potentiels en fonction de leur importance, de leur capacité à être mis en pratique et de leur faisabilité. Une liste définitive d’indicateurs et de mesures potentielles a ensuite été mise au point, en fonction des résultats de ces consultations et de considérations clés relatives aux politiques. Résultats : Trente-neuf indicateurs répartis en huit domaines relevant des CAA et quatre indicateurs relevant des résultats liés à la santé et aux conditions sociales à long terme ont été sélectionnés. Tous sont conformes à l’objectif énoncé, à savoir l’évaluation des

  1. Application of phase diagrams to obtain a new surfactant-based fracturing gel; Aplicacao de diagrama de fases para obtencao de um novo gel de fraturamento hidraulico

    Energy Technology Data Exchange (ETDEWEB)

    Dantas, Tereza N. de Castro; Santana, Vanessa C.; Dantas Neto, Afonso A.; Franca Neta, Luzia S. de; Albuquerque, Heraldo S. [Rio Grande do Norte Univ., Natal, RN (Brazil)]. E-mail: tereza@eq.ufrn.br

    2003-07-01

    Through pseudo ternary phases diagram was defined a gel area with the objective of obtaining a new surfactant-based fracturing gel. The surfactant used was synthesized from regional vegetable oil. Fracturing gel properties, like: viscosity, leak off coefficient and proppant-settling rate were analyzed. The obtained results with the surfactant-based gel had its properties compared with a HPG-based gel (hydroxypropyl guar). Rheological tests was accomplished at 100 s{sup -1} being varied the temperature from 26 to 86 deg C, where the surfactant-based gel showed great results. The leak off coefficient was determined by static filtration and the new gel presented smaller coefficient in relation to the HPG gel. The proppant-setting rate was also determined in the gel and, the surfactant-based gel showed good static proppant support. One can conclude that obtained gel presents compatible characteristics when compared with the HPG gel, without the inconvenience of leaving insoluble residues in the well. (author)

  2. Energy-Efficient Bioalcohol Recovery by Gel Stripping

    Science.gov (United States)

    Godbole, Rutvik; Ma, Lan; Hedden, Ronald

    2014-03-01

    Design of energy-efficient processes for recovering butanol and ethanol from dilute fermentations is a key challenge facing the biofuels industry due to the high energy consumption of traditional multi-stage distillation processes. Gel stripping is an alternative purification process by which a dilute alcohol is stripped from the fermentation product by passing it through a packed bed containing particles of a selectively absorbent polymeric gel material. The gel must be selective for the alcohol, while swelling to a reasonable degree in dilute alcohol-water mixtures. To accelerate materials optimization, a combinatorial approach is taken to screen a matrix of copolymer gels having orthogonal gradients in crosslinker concentration and hydrophilicity. Using a combination of swelling in pure solvents, the selectivity and distribution coefficients of alcohols in the gels can be predicted based upon multi-component extensions of Flory-Rehner theory. Predictions can be validated by measuring swelling in water/alcohol mixtures and conducting h HPLC analysis of the external liquid. 95% + removal of butanol from dilute aqueous solutions has been demonstrated, and a mathematical model of the unsteady-state gel stripping process has been developed. NSF CMMI Award 1335082.

  3. Chiromagnetic nanoparticles and gels

    Science.gov (United States)

    Yeom, Jihyeon; Santos, Uallisson S.; Chekini, Mahshid; Cha, Minjeong; de Moura, André F.; Kotov, Nicholas A.

    2018-01-01

    Chiral inorganic nanostructures have high circular dichroism, but real-time control of their optical activity has so far been achieved only by irreversible chemical changes. Field modulation is a far more desirable path to chiroptical devices. We hypothesized that magnetic field modulation can be attained for chiral nanostructures with large contributions of the magnetic transition dipole moments to polarization rotation. We found that dispersions and gels of paramagnetic Co3O4 nanoparticles with chiral distortions of the crystal lattices exhibited chiroptical activity in the visible range that was 10 times as strong as that of nonparamagnetic nanoparticles of comparable size. Transparency of the nanoparticle gels to circularly polarized light beams in the ultraviolet range was reversibly modulated by magnetic fields. These phenomena were also observed for other nanoscale metal oxides with lattice distortions from imprinted amino acids and other chiral ligands. The large family of chiral ceramic nanostructures and gels can be pivotal for new technologies and knowledge at the nexus of chirality and magnetism.

  4. Acoustic evaluation of polymer gel dosimeters

    International Nuclear Information System (INIS)

    Mather, M.L.; De Deene, Y.; Baldock, C.; Whittaker, A.K.

    2002-01-01

    Advances in radiotherapy treatment techniques such as intensity modulated radiotherapy are placing increasing demands on radiation dosimetry for verification of dose distributions in 3D. In response, polymer gel dosimeters that are capable of recording dose distributions in 3D are currently being developed. Recently, a new technique for evaluation of absorbed dose distributions in these dosimeters using ultrasound was introduced. The current work aims to demonstrate the potential of ultrasound as an evaluation technique for polymer gel dosimeters and to investigate the ultrasound properties of two different dosimeter formulations, PAG and MAGIC gels

  5. Polymer architecture of magnetic gels: a review

    Science.gov (United States)

    Weeber, Rudolf; Hermes, Melissa; Schmidt, Annette M.; Holm, Christian

    2018-02-01

    In this review article, we provide an introduction to ferrogels, i.e. polymeric gels with embedded magnetic particles. Due to the interplay between magnetic and elastic properties of these materials, they are promising candidates for engineering and biomedical applications such as actuation and controlled drug release. Particular emphasis will be put on the polymer architecture of magnetic gels since it controls the degrees of freedom of the magnetic particles in the gel, and it is important for the particle-polymer coupling determining the mechanisms available for the gel deformation in magnetic fields. We report on the different polymer architectures that have been realized so far, and provide an overview of synthesis strategies and experimental techniques for the characterization of these materials. We further focus on theoretical and simulational studies carried out on magnetic gels, and highlight their contributions towards understanding the influence of the gels’ polymer architecture.

  6. Epidemic models for phase transitions: application to a physical gel

    Science.gov (United States)

    Bilge, A. H.; Pekcan, O.; Kara, S.; Ogrenci, A. S.

    2017-09-01

    Carrageenan gels are characterized by reversible sol-gel and gel-sol transitions under cooling and heating processes and these transitions are approximated by generalized logistic growth curves. We express the transitions of carrageenan-water system, as a representative of reversible physical gels, in terms of a modified Susceptible-Infected-Susceptible epidemic model, as opposed to the Susceptible-Infected-Removed model used to represent the (irreversible) chemical gel formation in the previous work. We locate the gel point Tc of sol-gel and gel-sol transitions and we find that, for the sol-gel transition (cooling), Tc > Tsg (transition temperature), i.e. Tc is earlier in time for all carrageenan contents and moves forward in time and gets closer to Tsg as the carrageenan content increases. For the gel-sol transition (heating), Tc is relatively closer to Tgs; it is greater than Tgs, i.e. later in time for low carrageenan contents and moves backward as carrageenan content increases.

  7. Development and dosimetric evaluation of radiochromic PCDA vesicle gel dosimeters

    International Nuclear Information System (INIS)

    Sun, P.; Fu, Y.C.; Hu, J.; Hao, N.; Huang, W.; Jiang, B.

    2016-01-01

    The gel dosimeter has the unique capacity in recording radiation dose distribution in three dimensions (3D), which has the specific advantages in dosimetry measurements where steep dose gradients exist, such as in intensity-modulated radiation therapy (IMRT), brachytherapy and so on. Some 3D dosimeters, such as Fricke gel dosimeters, polymer gel dosimeters, the PRESAGE plastic dosimeters and micelle gel dosimeters have appeared recently. However, there are several disadvantages of these 3D dosimeters limit their application in radiotherapy dose verification. In this study, a novel radiochromic gel dosimeter for 3D dose verification of radiotherapy was developed by dispersing nanovesicles self-assembled by 10,12-pentacosadiynoic acid (PCDA) into the tissue equivalence gel matrix. The characteristics of radiochromic PCDA vesicle gel dosimeters were evaluated. The results indicate that these radiochromic gel dosimeters have good linear dose response to X-ray irradiation in the dose range of 2–100 Gy. In addition, the radiochromic gel dosimeters breakthrough the limitations of the existing gel dosimeters such as diffusion effect, post-radiation effect, and poor forming ability. The response of the gel dosimeter does not show any dose rate dependence, energy dependence and temperature effect, and there was no obvious difference in the gel response between single and cumulative dose of fractional irradiation. Hence, the radiochromic PCDA vesicle gel dosimeters developed in this study could be generally applied to 3D dose verification in radiotherapy. - Highlights: • A novel radiochromic gel dosimeter was developed by dispersing PCDA nanovesicles into the tissue equivalence gel matrix. • This nanovesicle overcomes the dose image blurring caused by the diffusion of monomer molecules. • This nanovesicle limits the polymer chain growth, so as to reduce the post-radiation effect. • The gel matrixes possess excellent tissue equivalence and elastic strength, which

  8. Strippable gel for decontamination of contaminated metallic surfaces

    International Nuclear Information System (INIS)

    Banerjee, D.; Sandhya, U.; Khot, S.A.; Srinivas, C.; Wattal, P.K.

    2013-01-01

    Periodic decontamination of radioactive laboratories including fume hoods, glove boxes and all surfaces used for handling, processing and transporting radioactive materials is mandatory in all nuclear installations as this reduces spread of contamination and decreases total man rem exposure. Conventionally, chemical decontaminating agents or surfactant solutions are used for this purpose. However, this approach leads to generation of large volume of secondary radioactive waste. The use of strippable gel is an attractive alternative with low secondary waste generation particularly where removal of loose or weakly fixed contamination is necessary and also when the decontaminated material are to be reused, for e.g. decontamination of fume hoods, glove boxes, transport casks, spent fuel storage racks, control rod drive transport containers etc. Literature on gel formulations is scarce and mostly in the patent form. The sustained effort on gel formulation development has resulted in a basic gel formulation. The gel is a highly viscous water-based organic polymer, particularly suitable for application on vertical surfaces including difficult to reach metallic surfaces of complex geometry and not just limited to horizontal surfaces. The gel can be easily applied on contaminated surfaces by brushing or spraying. Curing of the gel is complete within 16-24 hours under ambient conditions and can then be removed by peeling as a dry sheet. While curing, the contaminants are trapped in gel either physically or chemically depending upon the nature of the contaminant. Salient features of cured gel include that it is water soluble and can be disposed off after immobilization in cement. Decontamination performance of the gel was initially evaluated by applying it on SS planchettes contaminated with known amount of radionuclides such as Cs(I), Co(II) and Ce(III). The measured decontamination factor was found to be in the range of 50-500, lowest for Ce(III) and highest for Co

  9. The mechanism and properties of acid-coagulated milk gels

    Directory of Open Access Journals (Sweden)

    Chanokphat Phadungath

    2005-03-01

    Full Text Available Acid-coagulated milk products such as fresh acid-coagulated cheese varieties and yogurt areimportant dairy food products. However, little is known regarding the mechanisms involved in gel formation, physical properties of acid gels, and the effects of processing variables such as heat treatment and gelation temperature on the important physical properties of acid milk gels. This paper reviews the modern concepts of possible mechanisms involved in the formation of particle milk gel aggregation, along with recent developments including the use of techniques such as dynamic low amplitude oscillatory rheology to observe the gel formation process, and confocal laser scanning microscopy to monitor gel microstructure.

  10. Explorative data analysis of two-dimensional electrophoresis gels

    DEFF Research Database (Denmark)

    Schultz, J.; Gottlieb, D.M.; Petersen, Marianne Kjerstine

    2004-01-01

    of gels is presented. First, an approach is demonstrated in which no prior knowledge of the separated proteins is used. Alignment of the gels followed by a simple transformation of data makes it possible to analyze the gels in an automated explorative manner by principal component analysis, to determine......Methods for classification of two-dimensional (2-DE) electrophoresis gels based on multivariate data analysis are demonstrated. Two-dimensional gels of ten wheat varieties are analyzed and it is demonstrated how to classify the wheat varieties in two qualities and a method for initial screening...... if the gels should be further analyzed. A more detailed approach is done by analyzing spot volume lists by principal components analysis and partial least square regression. The use of spot volume data offers a mean to investigate the spot pattern and link the classified protein patterns to distinct spots...

  11. Further developments and applications of layer gel dosimetry

    International Nuclear Information System (INIS)

    Gambarini, G; Carrara, M; Colli, V; Gay, S; Tomatis, S

    2004-01-01

    The method used to perform dosimetry with Fricke-xylenol orange-infused gels in form of layers remains the most reliable method for in-phantom dose profiling and imaging in high fluxes of thermal and epithermal neutrons. Gel-dosimeters in form of layers really give the possibility not only of obtaining spatial dose distributions but also of achieving measurements of each dose contribution in neutron fields. These advantages arise from the layer-geometry thanks to which neutron transport is not sensibly altered, even if the elemental gel composition is changed adding particular isotopes (for example 10 B), as necessary to perform the separation of dose contributions. The gel matrix composition and the experimental procedures, adopted for both dosimeter preparation and analysis, have been already described in previous works. In the present work, the improvements of the method employed for gel analysis, dose imaging and gel applications are illustrated

  12. Encapsulation of biological species in sol-gel matrices

    International Nuclear Information System (INIS)

    Finnie, K.S.; Bartlett, J.R.; Woolfrey, J.L.

    2000-01-01

    Two examples are given of the gelation of silica sols containing bio catalysts, resulting in their encapsulation in porous matrices. Urease was encapsulated in gels made from a mixture of TMOS and alkyltrimethoxysilane. Enzyme activities, monitored by measuring the rate of production of ammoniacal nitrogen as urea was decomposed, ranged up to 60% of that of the unencapsulated species. Anaerobic sulphate-reducing bacteria were encapsulated in a gel produced from colloidal silica, thus avoiding contact with alcohol. The detection of H 2 S produced in the doped gel indicated that the bacteria were able to continue normal metabolic function within the gel matrix. A gel initially doped with ∼ 5 x 10 5 cells cm -3 , exhibited an optimum sulphate reduction rate of 11 ug h -1 cm -3 ; this reduction rate was quickly re-established after storage of the gel for 14 weeks. Copyright (2000) The Australian Ceramic Society

  13. Ionic liquid gel materials: applications in green and sustainable chemistry

    OpenAIRE

    Marr, Patricia C.; Marr, Andrew C.

    2016-01-01

    Ionic liquid gel materials offer a way to further utilise ionic liquids in technological applications. Combining the controlled and directed assembly of gels, with the diverse applications of ionic liquids, enables the design of a heady combination of functional tailored materials, leading to the development of task specific / functional ionic liquid gels. This review introduces gels and gel classification, focusing on ionic liquid gels and their potential roles in a more sustainable future. ...

  14. Improving Learning Tasks for Mentally Handicapped People Using AmI Environments Based on Cyber-Physical Systems

    Directory of Open Access Journals (Sweden)

    Diego Martín

    2018-01-01

    Full Text Available A prototype to improve learning tasks for mentally handicapped people is shown in this research paper using ambient intelligence techniques and based on cyber-physical systems. The whole system is composed of a worktable, a cyber-glove (both with several RFID and NFC detection zones, and an AmI software application for modeling and workflow guidance. A case study was carried out by the authors where sixteen mentally handicapped people and 3 trainers were involved in the experiment. The experiment consisted in the execution of several memorization tasks of movements of objects using the approach presented in this paper. The results obtained were very interesting, indicating that this kind of solutions are feasible and allow the learning of complex tasks to some types of mentally handicapped people. In addition, at the end of the paper are presented some lessons learned after performing the experimentation.

  15. Equipment for production of hydrogel by sol-gel method

    International Nuclear Information System (INIS)

    Urbanek, V.

    1975-01-01

    The method of uranyl gel preparation is described by the sol-gel process of the internal gelation type. A laboratory-scale equipment with an output of 1.5 kg of gel per hour was built at the Nuclear Research Institute, Rez; the diameter of the microspheres produced may vary between 0.5 and 4.0 mm. The reliability of the equipment was verified by producing several tens of kilograms of uranyl gels and of gels based on other non-nuclear materials. (author)

  16. Electrochemical behavior of ionically crosslinked polyampholytic gel electrolytes

    International Nuclear Information System (INIS)

    Chen Wanyu; Tang Haitao; Ou Ziwei; Wang Hong; Yang Yajiang

    2007-01-01

    An ionic complex of anionic and cationic monomers was obtained by protonation of (N,N-diethylamino)ethylmethacrylate (DEA) with acrylic acid (AAc). Free radical copolymerization of the ionic complex and acrylamide (AAm), yielded the ionically crosslinked polyampholytic gel electrolytes [poly(AAc-DEA-AAm), designated as PADA] using two types of organic solvents containing a lithium salt. The PADA gel electrolyte exhibited good thermal stability shown by the DSC thermogram. The impedance analysis at temperatures ranging from -30 to 75 deg. C indicated that the ionic conductivities of the PADA gel electrolytes were rather close to those of liquid electrolytes. The temperature dependence of the ionic conductivities was found to be in accord with the Arrhenius equation. Moreover, the ionic conductivities of PADA gel electrolytes increased with an increase of the molar ratios of cationic/anionic monomers. The ionic conductivities of PADA gels prepared in solvent mixtures of propylene carbonate, ethyl methyl ether and dioxolane (3:1:1, v/v) were higher than those of PADA gels prepared in propylene carbonate only. Significantly, the ionic conductivities of two kinds of PADA gel electrolytes were in the range of 10 -3 and 10 -4 S cm -1 even at -30 deg. C. The electrochemical windows of PADA gel electrolytes measured by cyclic voltammetry were in the range from -1 V to 4.5 V

  17. Electrophoretic Porosimetry of Sol-Gels

    Science.gov (United States)

    Snow, L. A.; Smith, D. D.; Sibille, L.; Hunt, A. J.; Ng, J.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    It has been hypothesized that gravity has an effect on the formation and resulting microstructure of sol-gels. In order to more clearly resolve the effect of gravity, pores may be non-destructively analyzed in the wet gel, circumventing the shrinkage and coarsening associated with the drying procedure. We discuss the development of an electrophoretic technique, analogous to affinity chromatography, for the determination of pore size distribution and its application to silica gels. Specifically a monodisperse charged dye is monitored by an optical densitometer as it moves through the wet gel under the influence of an electric field. The transmittance data (output) represents the convolution of the dye concentration profile at the beginning of the run (input) with the pore size distribution (transfer function), i.e. linear systems theory applies. Because of the practical difficulty in producing a delta function input dye profile we prefer instead to use a step function. Average pore size is then related to the velocity of this dye front, while the pore size distribution is related to the spreading of the front. Preliminary results of this electrophoretic porosimetry and its application to ground and space-grown samples will be discussed.

  18. Viscoplastic fracture transition of a biopolymer gel.

    Science.gov (United States)

    Frieberg, Bradley R; Garatsa, Ray-Shimry; Jones, Ronald L; Bachert, John O; Crawshaw, Benjamin; Liu, X Michael; Chan, Edwin P

    2018-06-13

    Physical gels are swollen polymer networks consisting of transient crosslink junctions associated with hydrogen or ionic bonds. Unlike covalently crosslinked gels, these physical crosslinks are reversible thus enabling these materials to display highly tunable and dynamic mechanical properties. In this work, we study the polymer composition effects on the fracture behavior of a gelatin gel, which is a thermoreversible biopolymer gel consisting of denatured collagen chains bridging physical network junctions formed from triple helices. Below the critical volume fraction for chain entanglement, which we confirm via neutron scattering measurements, we find that the fracture behavior is consistent with a viscoplastic type process characterized by hydrodynamic friction of individual polymer chains through the polymer mesh to show that the enhancement in fracture scales inversely with the squared of the mesh size of the gelatin gel network. Above this critical volume fraction, the fracture process can be described by the Lake-Thomas theory that considers fracture as a chain scission process due to chain entanglements.

  19. Silica scintillating materials prepared by sol-gel methods

    International Nuclear Information System (INIS)

    Werst, D.W.; Sauer, M.C. Jr.; Cromack, K.R.; Lin, Y.; Tartakovsky, E.A.; Trifunac, A.D.

    1993-01-01

    Silica was investigated as a rad-hard alternative to organic polymer hosts for organic scintillators. Silica sol-gels were prepared by hydrolysis of tetramethoxysilane in alcohol solutions. organic dyes were incorporated into the gels by dissolving in methanol at the sol stage of gel formation. The silica sol-gel matrix is very rad-hard. The radiation stability of silica scintillators prepared by this method is dye-limited. Transient radioluminescence was measured following excitation with 30 ps pulses of 20 MeV electrons

  20. A theory for fracture of polymeric gels

    Science.gov (United States)

    Mao, Yunwei; Anand, Lallit

    2018-06-01

    A polymeric gel is a cross-linked polymer network swollen with a solvent. If the concentration of the solvent or the deformation is increased to substantial levels, especially in the presence of flaws, then the gel may rupture. Although various theoretical aspects of coupling of fluid permeation with large deformation of polymeric gels are reasonably well-understood and modeled in the literature, the understanding and modeling of the effects of fluid diffusion on the damage and fracture of polymeric gels is still in its infancy. In this paper we formulate a thermodynamically-consistent theory for fracture of polymeric gels - a theory which accounts for the coupled effects of fluid diffusion, large deformations, damage, and also the gradient effects of damage. The particular constitutive equations for fracture of a gel proposed in our paper, contain two essential new ingredients: (i) Our constitutive equation for the change in free energy of a polymer network accounts for not only changes in the entropy, but also changes in the internal energy due the stretching of the Kuhn segments of the polymer chains in the network. (ii) The damage and failure of the polymer network is taken to occur by chain-scission, a process which is driven by the changes in the internal energy of the stretched polymer chains in the network, and not directly by changes in the configurational entropy of the polymer chains. The theory developed in this paper is numerically implemented in an open-source finite element code MOOSE, by writing our own application. Using this simulation capability we report on our study of the fracture of a polymeric gel, and some interesting phenomena which show the importance of the diffusion of the fluid on fracture response of the gel are highlighted.

  1. Gadolinium-loaded gel scintillators for neutron and antineutrino detection

    Science.gov (United States)

    Riddle, Catherine Lynn; Akers, Douglas William; Demmer, Ricky Lynn; Paviet, Patricia Denise; Drigert, Mark William

    2016-11-29

    A gadolinium (Gd) loaded scintillation gel (Gd-ScintGel) compound allows for neutron and gamma-ray detection. The unique gel scintillator encompasses some of the best features of both liquid and solid scintillators, yet without many of the disadvantages associated therewith. Preferably, the gel scintillator is a water soluble Gd-DTPA compound and water soluble fluorophores such as: CdSe/ZnS (or ZnS) quantum dot (Q-dot) nanoparticles, coumarin derivatives 7-hydroxy-4-methylcoumarin, 7-hydroxy-4-methylcoumarin-3-acetic acid, 7-hydroxycoumarin-3-carboxylic acid, and Alexa Fluor 350 as well as a carbostyril compound, carbostyril 124 in a stable water-based gel, such as methylcellulose or polyacrylamide polymers. The Gd-loaded ScintGel allows for a homogenious distribution of the Gd-DTPA and the fluorophores, and yields clean fluorescent emission peaks. A moderator, such as deuterium or a water-based clear polymer, can be incorporated in the Gd-ScintGel. The gel scintillators can be used in compact detectors, including neutron and antineutrino detectors.

  2. Multiple-phase behavior and memory effect of polymer gel

    CERN Document Server

    Annaka, M; Nakahira, T; Sugiyama, M; Hara, K; Matsuura, T

    2002-01-01

    A poly(4-acrylamidosalicylic acid) gel (PASA gel) exhibits multiple phases as characterized by distinct degrees of swelling; the gel can take one of four different swelling values, but none of the intermediate values. The gel has remarkable memory: the phase behavior of the gel depends on whether the gel has experienced the most swollen phase or the most collapsed phase in the immediate past. The information is stored and reversibly erased in the form of a macroscopic phase transition behavior. The structure factors corresponding to these four phases were obtained by SANS, which indicated the presence of characteristic structures depending on pH and temperature, particularly in the shrunken state. (orig.)

  3. Investigating potential physicochemical errors in polymer gel dosimeters

    International Nuclear Information System (INIS)

    Sedaghat, Mahbod; Lepage, Martin; Bujold, Rachel

    2011-01-01

    Measurement errors in polymer gel dosimetry can originate either during irradiation or scanning. One concern related to the exothermic nature of polymerization reaction was that the heat released in polymer gel dosimeters during irradiation modifies their dose response. In this paper, the effect of heat released from the exothermal polymerization reaction on the dose response of a number of dosimeters was studied. In addition, we investigated whether heat-generated geometric distortion existed in newly proposed gel dosimeters that contain highly thermoresponsive polymers. Our results suggest that despite a significant internal temperature increase in some gel compositions, their dose responses are not affected when oxygen is well expelled mechanically from the gel mixture. We also report on significant pre-irradiation instability in some recently developed polymer gel dosimeters but that geometric distortions were not observed. Data obtained by a set of small calibration vials are compared to those obtained from larger phantoms, and potential physicochemical causes of deviations between them are identified.

  4. Investigating potential physicochemical errors in polymer gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Sedaghat, Mahbod; Lepage, Martin [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); Bujold, Rachel, E-mail: martin.lepage@usherbrooke.ca [Service de radio-oncologie, Centre hospitalier universitaire de Sherbrooke, Sherbrooke, QC (Canada)

    2011-09-21

    Measurement errors in polymer gel dosimetry can originate either during irradiation or scanning. One concern related to the exothermic nature of polymerization reaction was that the heat released in polymer gel dosimeters during irradiation modifies their dose response. In this paper, the effect of heat released from the exothermal polymerization reaction on the dose response of a number of dosimeters was studied. In addition, we investigated whether heat-generated geometric distortion existed in newly proposed gel dosimeters that contain highly thermoresponsive polymers. Our results suggest that despite a significant internal temperature increase in some gel compositions, their dose responses are not affected when oxygen is well expelled mechanically from the gel mixture. We also report on significant pre-irradiation instability in some recently developed polymer gel dosimeters but that geometric distortions were not observed. Data obtained by a set of small calibration vials are compared to those obtained from larger phantoms, and potential physicochemical causes of deviations between them are identified.

  5. Natural gels in the Yucca Mountain Area, Nevada, USA

    International Nuclear Information System (INIS)

    Levy, S.S.

    1991-01-01

    Relict gels at Yucca Mountain include pore- and fracture-fillings of silica and zeolite related to diagenetic and hydrothermal alternation of vitric tuffs. Water-rich free gels in fractures at Rainier Mesa consist of smectite with or without silica-rich gel fragments. Gels are being studied for their potential role in transport of radionuclides from a nuclear-waste repository

  6. Antioxidant effect of green tea on polymer gel dosimeter

    International Nuclear Information System (INIS)

    Samuel, E J J; Sathiyaraj, P; Deena, T; Kumar, D S

    2015-01-01

    Extract from Green Tea (GTE) acts as an antioxidant in acrylamide based polymer gel dosimeter. In this work, PAGAT gel was used for investigation of antioxidant effect of GTE.PAGAT was called PAGTEG (Polyacrylamide green tea extract gel dosimeter) after adding GTE. Free radicals in water cause pre polymerization of polymer gel before irradiation. Polyphenols from GTE are highly effective to absorb the free radicals in water. THPC is used as an antioxidant in polymer gel dosimeter but here we were replaced it by GTE and investigated its effect by spectrophotometer. GTE added PAGAT samples response was lower compared to THPC added sample. To increase the sensitivity of the PAGTEG, sugar was added. This study confirmed that THPC was a good antioxidant for polymer gel dosimeter. However, GTE also can be used as an antioxidant in polymer gel if use less quantity (GTE) and add sugar as sensitivity enhancer

  7. Sillica Gel-Amine from Geothermal Sludge

    Science.gov (United States)

    Muljani, S.; Pujiastuti, C.; Wicaksono, P.; Lutfianingrum, R.

    2018-01-01

    Silica Gel-Amine (SGA) has been made from geothermal sludge by grafting amine method. Sodium silicate solution is prepared by extracted geothermal sludge powder using sodium hidroxide solution then acidification in the range of pH 5 - 9 by using tartaric acid 1N. The grafting process uses 1 ml of ammonia solution and 10 ml of toluene at a rate of 0.1 ml min-1 accompanied by a reflux process. The amine grafting is done in two methods. The first method is grafting amine in silicate solution and the second method is grafting amine in washed gel. Product SGA was confirmed by FTIR, TGA-DTG and BET characterization. The results show that the pH affects the amount of amine that is grafted onto silica gel. Differences in grafting method affect the size of the pore and surface area. SGA product prepared by grafting washed gel at pH 8 have pore diameter of 12.06 nm, surface area of 173.44 m2g-1, and mass of decomposed amine compound 0.4 mg. In the presence of amine groups on the silica gel surface, these adsorbents may be able to selectively adsorb CO2 gas from natural gas.

  8. Some rheological properties of sodium caseinate-starch gels.

    Science.gov (United States)

    Bertolini, Andrea C; Creamer, Lawrence K; Eppink, Mieke; Boland, Mike

    2005-03-23

    The influence of sodium caseinate on the thermal and rheological properties of starch gels at different concentrations and from different botanical sources was evaluated. In sodium caseinate-starch gels, for all starches with the exception of potato starch, the sodium caseinate promoted an increase in the storage modulus and in the viscosity of the composite gel when compared with starch gels. The addition of sodium caseinate resulted in an increase in the onset temperature, the gelatinization temperature, and the end temperature, and there was a significant interaction between starch and sodium caseinate for the onset temperature, the peak temperature, and the end temperature. Microscopy results suggested that sodium caseinate promoted an increase in the homogeneity in the matrix of cereal starch gels.

  9. A NOVEL GEL ELECTROLYTE FOR VALVE-REGULATED LEAD ACID BATTERY

    Directory of Open Access Journals (Sweden)

    Metin GENÇTEN

    2017-03-01

    Full Text Available A novel gel electrolyte system used in lead-acid batteries was investigated in this work. The gel systems were prepared by addition different amount of Al2O3, TiO2 and B2O3 into the gelled system consisting of 6 wt% fumed silica and 30 wt% sulfuric acid solution. The anodic peak currents and peak redox capacities of the gel electrolytes were characterized by cyclic voltammetric method. They decreased by the time B2O3 and Al2O3 were used as additives in fumed silica based gel electrolyte system. However, these values increased by the adding 3.0 wt% of TiO2. The solution and charge transfer resistances of the gel electrolytes were investigated by electrochemical impedance spectroscopy. While the solution resistances were lower in gel systems having different amount additives than pure fumed silica based gel, the charge transfer resistance was the lowest in gel electrolytes consisting fumed silica and fumed silica-TiO2. The battery performances were studied by obtaining discharge curves of prepared gel electrolytes. The performance of gelled systems were higher than that of non-gelled electrolyte at room temperature. The mixture of fumed silica-TiO2 was suggested an alternative gel formulation for gel VRLA batteries.

  10. Coordination Polymer Gels by Electron Beam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Ha; Cho, Young Je; Jung, Jong Hwa [Gyeongsang National Univ., Jinju (Korea, Republic of)

    2011-07-01

    Hydrogenation of a pyridine derivative possessing tetrazole moieties as end groups, without long alkyl chain groups, results in the formation of a Mg(NO{sub 3}){sub 2} coordination polymer gel. The polymer exhibits a strong fluorescence enhancement upon gel formation. 1 can also be gloated with a variety of magnesium anions such as SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Cl{sup -}, Br{sup -} and I{sup -}, indicating that the coordination polymer gel formation of 1 does not strongly depends on anions. The Seam and ABM images of Mg{sup 2+} coordination polymer gel 1 display a flabbier network with several micrometers long, widths in the range 60-70 nm and thicknesses of about 3 nm. In addition, photophysical studies show that the hydrogel exhibits a typical {pi}-{pi} transition and gives rise to high fluorescence behavior. The coordination polymer hydrogel exhibits viscoelastic behavior as evidenced from the rheological studies.

  11. PCR amplification on microarrays of gel immobilized oligonucleotides

    Science.gov (United States)

    Strizhkov, Boris; Tillib, Sergei; Mikhailovich, Vladimir; Mirzabekov, Andrei

    2003-11-04

    The invention relates two general methods for performing PCR amplification, combined with the detection and analysis of the PCR products on a microchip. In the first method, the amplification occurs both outside and within a plurality of gel pads on a microchip, with at least one oligonucleotide primer immobilized in a gel pad. In the second method, PCR amplification also takes place within gel pads on a microchip, but the pads are surrounded by a hydrophobic liquid such as that which separates the individual gel pads into environments which resemble micro-miniaturized test tubes.

  12. Protein electrophoretic migration data from custom and commercial gradient gels

    Directory of Open Access Journals (Sweden)

    Andrew J. Miller

    2016-12-01

    Full Text Available This paper presents data related to the article “A method for easily customizable gradient gel electrophoresis” (A.J. Miller, B. Roman, E.M. Norstrom, 2016 [1]. Data is presented on the rate of electrophoretic migration of proteins in both hand-poured and commercially acquired acrylamide gradient gels. For each gel, migration of 9 polypeptides of various masses was measured upon completion of gel electrophoresis. Data are presented on the migration of proteins within separate lanes of the same gel as well as migration rates from multiple gels.

  13. Fabrication and Optimization of a PAGATA Gel Dosimeter: Increasing the Melting Point of the PAGAT Gel Dosimeter with Agarose Additive

    Directory of Open Access Journals (Sweden)

    Bakhtiar Azadbakht

    2010-12-01

    Full Text Available Introduction: The PAGAT polymer gel dosimeter melts at 30 ˚C and even at room temperature during the summer, so it needs to be kept in a cool place such as a refrigerator. To increase the stability of the PAGAT gel, different amounts of agarose were added to the PAGAT gel composition and the PAGATA gel was manufactured. Material and Methods: The PAGATA gel vials were irradiated using a Co-60 machine. Then, the samples were evaluated using a 1.5 T Siemens MRI scanner. The ingredients of the PAGATA normoxic gel dosimeter were 4.5% N-N' methylen-bis-acrylamide, 4.5% acrylamide, 4.5% gelatine, 5 mM tetrakis (THPC, 0.01 mM hydroquinone (HQ, 0.5% agarose and 86% de-ionized water (HPLC. Results: Melting point and sensitivity of the PAGAT gel dosimeter with addition of 0.0, 0.3, 0.5, 1.0, 1.5 and 2.0% of agarose were measured, in which the melting points were increased to 30, 82, 86, 88, 89 and 90°C and their sensitivities found to be 0.113, 0.1059, 0.125, 0.122, 0.115 and 0.2  respectively. Discussion and Conclusions: Adding agarose increased the sensitivity and background R2 of the evaluated samples. The optimum amount of agarose was found to be 0.5% regarding these parameters and also the melting point of the gel dosimeter. A value of 0.5% agarose was found to be an optimum value considering the increase of sensitivity to 0.125 and melting point to 86°C but at the expense of increasing the background R2 to 4.530.

  14. Implementation of MRI gel dosimetry in radiation therapy

    International Nuclear Information System (INIS)

    Baeck, S.Aa.J.

    1998-12-01

    Gel dosimetry was used together with magnetic resonance imaging (MRI) to measure three-dimensional absorbed dose distributions in radiation therapy. Two different dosimeters were studied: ferrous- and monomer gel, based on the principles of radiation-induced oxidation and polymerisation, respectively. Single clinical electron and photon beams were evaluated and gel dose distributions were mainly within 2% of conventional detector results. The ferrous-gel was also used for clinical proton beams. A decrease in signal per absorbed dose was found close to the end of the range of the protons (15-20%). This effect was explained as a linear energy transfer dependence, further supported with Monte Carlo simulations. A method for analysing and comparing data from treatment planning system (TPS) and gel measurements was developed. The method enables a new pixel by pixel evaluation, isodose comparison and dose volume histogram verification. Two standard clinical radiation therapy procedures were examined using the developed TPS verification method. The treatment regimes included several beams of different radiation qualities. The TPS calculated data were in very good agreement with the dose distribution measured by the ferrous-gel. However, in a beam abutment region, larger dose difference was found. Beam adjustment errors and a minor TPS underestimation of the lateral scatter contribution outside the primary electron beam may explain the discrepancy. The overall uncertainty in the ferrous-gel dose determination was considerably reduced using an optimised MRI acquisition protocol and a new MRI scanner. The relative dose uncertainty was found to be better than 3.3% for all dose levels (95% confidence level). Using the method developed for comparing measured gel data with calculated treatment plans, the gel dosimetry method was proven to be a useful tool for radiation treatment planning verification

  15. Implementation of MRI gel dosimetry in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Baeck, S.Aa.J

    1998-12-01

    Gel dosimetry was used together with magnetic resonance imaging (MRI) to measure three-dimensional absorbed dose distributions in radiation therapy. Two different dosimeters were studied: ferrous- and monomer gel, based on the principles of radiation-induced oxidation and polymerisation, respectively. Single clinical electron and photon beams were evaluated and gel dose distributions were mainly within 2% of conventional detector results. The ferrous-gel was also used for clinical proton beams. A decrease in signal per absorbed dose was found close to the end of the range of the protons (15-20%). This effect was explained as a linear energy transfer dependence, further supported with Monte Carlo simulations. A method for analysing and comparing data from treatment planning system (TPS) and gel measurements was developed. The method enables a new pixel by pixel evaluation, isodose comparison and dose volume histogram verification. Two standard clinical radiation therapy procedures were examined using the developed TPS verification method. The treatment regimes included several beams of different radiation qualities. The TPS calculated data were in very good agreement with the dose distribution measured by the ferrous-gel. However, in a beam abutment region, larger dose difference was found. Beam adjustment errors and a minor TPS underestimation of the lateral scatter contribution outside the primary electron beam may explain the discrepancy. The overall uncertainty in the ferrous-gel dose determination was considerably reduced using an optimised MRI acquisition protocol and a new MRI scanner. The relative dose uncertainty was found to be better than 3.3% for all dose levels (95% confidence level). Using the method developed for comparing measured gel data with calculated treatment plans, the gel dosimetry method was proven to be a useful tool for radiation treatment planning verification 103 refs, 20 figs, 6 tabs

  16. Agarose gel electrophoresis for the separation of DNA fragments.

    Science.gov (United States)

    Lee, Pei Yun; Costumbrado, John; Hsu, Chih-Yuan; Kim, Yong Hoon

    2012-04-20

    Agarose gel electrophoresis is the most effective way of separating DNA fragments of varying sizes ranging from 100 bp to 25 kb(1). Agarose is isolated from the seaweed genera Gelidium and Gracilaria, and consists of repeated agarobiose (L- and D-galactose) subunits(2). During gelation, agarose polymers associate non-covalently and form a network of bundles whose pore sizes determine a gel's molecular sieving properties. The use of agarose gel electrophoresis revolutionized the separation of DNA. Prior to the adoption of agarose gels, DNA was primarily separated using sucrose density gradient centrifugation, which only provided an approximation of size. To separate DNA using agarose gel electrophoresis, the DNA is loaded into pre-cast wells in the gel and a current applied. The phosphate backbone of the DNA (and RNA) molecule is negatively charged, therefore when placed in an electric field, DNA fragments will migrate to the positively charged anode. Because DNA has a uniform mass/charge ratio, DNA molecules are separated by size within an agarose gel in a pattern such that the distance traveled is inversely proportional to the log of its molecular weight(3). The leading model for DNA movement through an agarose gel is "biased reptation", whereby the leading edge moves forward and pulls the rest of the molecule along(4). The rate of migration of a DNA molecule through a gel is determined by the following: 1) size of DNA molecule; 2) agarose concentration; 3) DNA conformation(5); 4) voltage applied, 5) presence of ethidium bromide, 6) type of agarose and 7) electrophoresis buffer. After separation, the DNA molecules can be visualized under uv light after staining with an appropriate dye. By following this protocol, students should be able to: Understand the mechanism by which DNA fragments are separated within a gel matrix Understand how conformation of the DNA molecule will determine its mobility through a gel matrix Identify an agarose solution of appropriate

  17. Pulsed-field gel electrophoresis of bacterial chromosomes.

    Science.gov (United States)

    Mawer, Julia S P; Leach, David R F

    2013-01-01

    The separation of fragments of DNA by agarose gel electrophoresis is integral to laboratory life. Nevertheless, standard agarose gel electrophoresis cannot resolve fragments bigger than 50 kb. Pulsed-field gel electrophoresis is a technique that has been developed to overcome the limitations of standard agarose gel electrophoresis. Entire linear eukaryotic chromosomes, or large fragments of a chromosome that have been generated by the action of rare-cutting restriction endonucleases, can be separated using this technique. As a result, pulsed-field gel electrophoresis has many applications, from karyotype analysis of microbial genomes, to the analysis of chromosomal strand breaks and their repair intermediates, to the study of DNA replication and the identification of origins of replication. This chapter presents a detailed protocol for the preparation of Escherichia coli chromosomal DNA that has been embedded in agarose plugs, digested with the rare-cutting endonuclease NotI, and separated by contour-clamped homogeneous field electrophoresis. The principles in this protocol can be applied to the separation of all fragments of DNA whose size range is between 40 kb and 1 Mb.

  18. The Synthesis of a Novel Cellulose Physical Gel

    Directory of Open Access Journals (Sweden)

    Jiufang Duan

    2014-01-01

    Full Text Available Cellulose possessing β-cyclodextrin (β-CD was used as a host molecule and cellulose possessing ferrocene (Fc as a guest polymer. Infrared spectra, differential scanning calorimetry (DSC, ultraviolet spectroscopy (UV, and contact angle analysis were used to characterise the material structure and the inclusion behaviour. The results showed that the β-CD-cellulose and the Fc-cellulose can form inclusion complexes. Moreover, ferrocene oxidation, and reduction of state can be adjusted by sodium hypochlorite (NaClO as an oxidant and glutathione (GSH as a reductant. In this study, a physical gel based on β-CD-cellulose/Fc-cellulose was formed under mild conditions in which autonomous healing between cut surfaces occurred after 24 hours. The physical gel can be controlled in the sol-gel transition. The compressive strength of the Fc-cellulose/β-CD-cellulose gel increased with increased cellulose concentration. The host-guest interaction between the side chains of cellulose could strengthen the gel. The cellulose physical gel may eventually be used as a stimulus-responsive, healing material in biomedical applications.

  19. Applications of sol gel ceramic coatings

    International Nuclear Information System (INIS)

    Barrow, D.

    1996-01-01

    The sol gel method is a chemical technique in which polycrystalline ceramic films are fabricated from a solution of organometallic precursors. The technique is attractive for many industrial applications because it is a simple (films are processed in air), flexible (can be used to coat complex geometries) and cost effective (does not require expensive equipment) process. In addition, dense, high quality coatings can be achieved at much lower temperatures than is generally required for sintering bulk ceramics. In this paper the conventional sol gel method and the new datec process are reviewed and potential applications of sol gel coatings in automotive, aerospace, petrochemical, nuclear and electronic industries are discussed. (orig.)

  20. The Gel Generator option

    International Nuclear Information System (INIS)

    Boyd, R.E.

    1999-01-01

    The development of a national policy for guaranteeing an ample supply of 99m Tc to nuclear medicine, involves issues which go beyond the means by which radioactivation is achieved. Indeed, in such an exercise the pragmatic dictates of business and the sensitivities of politics must also be taken into account. Furthermore where a preference towards the nuclear reactor or the potential of cyclotrons is being questioned, the debate is incomplete if the only options that are considered are the fission-based 99 Mo generator versus the direct cyclotron production of 99m Tc. There is a third option (also neutron γ-based), an alternative to the fission 99 Mo generator, which ought not be overlooked. The application of low specific activity (n,γ) 99 Mo to a new type of generator, the Gel Generator, has been the focus of much research, particularly in Australia and more recently in China. After the initial concept had been established in the laboratory, the Australian researchers then undertook a comprehensive program of tests on the Gel Generator to assess its potential, either in the clinical laboratory or the centralised radiopharmacy, for supplying 99m Tc suitable for nuclear medicine. The outcome of this program was a clear indication that the Gel Generator innovation had the capability to provide both technical and economic advantages to the nuclear medicine industry. These advantages are described. Since that time the Gel Generator has been selected for routine use in China where it now satisfies more than 30% of the 99m Tc demand. (author)

  1. Meso-decorated self-healing gels: network structure and properties

    Science.gov (United States)

    Gong, Jin; Sawamura, Kensuke; Igarashi, Susumu; Furukawa, Hidemitsu

    2013-04-01

    Gels are a new material having three-dimensional network structures of macromolecules. They possess excellent properties as swellability, high permeability and biocompatibility, and have been applied in various fields of daily life, food, medicine, architecture, and chemistry. In this study, we tried to prepare new multi-functional and high-strength gels by using Meso-Decoration (Meso-Deco), one new method of structure design at intermediate mesoscale. High-performance rigid-rod aromatic polymorphic crystals, and the functional groups of thermoreversible Diels-Alder reaction were introduced into soft gels as crosslinkable pendent chains. The functionalization and strengthening of gels can be realized by meso-decorating the gels' structure using high-performance polymorphic crystals and thermoreversible pendent chains. New gels with good mechanical properties, novel optical properties and thermal properties are expected to be developed.

  2. Contaminant containment using polymer gel barriers

    NARCIS (Netherlands)

    Darwish, M.I.M.; Rowe, R.K.; Maarel, van der J.R.C.; Pel, L.; Huinink, H.P.; Zitha, P.L.J.

    2004-01-01

    Polymer gels are well known in the oil industry, but their potential for use as barriers to contaminant transport has not previously received significant study. As a first step, this paper examines the potential for a polyelectrolyte gel to serve as a barrier to the migration of sodium chloride. Two

  3. Sol-gel synthesis of hydroxyapatite

    International Nuclear Information System (INIS)

    Zupanski, M.D.; Lucena, M.P.P.; Bergmann, C.P.

    2010-01-01

    Hydroxyapatite (HAp) has been established as the calcium phosphate based compound with most applications in the biological field. Among the numerous techniques for synthesis of HAp, the sol-gel processing route affords great control over purity and formed phases using low processing temperatures. In addition, the sol-gel approach offers an option for homogeneous HAp coating on metal substrates, as well as the ability to generate nanocrystalline powders. In this work, the sol-gel synthesis of HAp was investigated employing triethyl phosphate and calcium nitrate tetrahydrate as phosphorous and calcium precursors, respectively. The aging effect on phase composition and powder morphology of the final product was studied in terms of temperature and aging time. The powders were studied by using X-ray diffraction, Fourier transform infrared spectroscopy, particle size distribution by laser diffraction and scanning electron microscopy. (author)

  4. Fundamentals of Polymer Gel Dosimeters

    Science.gov (United States)

    McAuley, Kim B.

    2006-12-01

    The recent literature on polymer gel dosimetry contains application papers and basic experimental studies involving polymethacrylic-acid-based and polyacrylamide-based gel dosimeters. The basic studies assess the relative merits of these two most commonly used dosimeters, and explore the effects of tetrakis hydroxymethyl phosphonium chloride (THPC) antioxidant on dosimeter performance. Polymer gel dosimeters that contain THPC or other oxygen scavengers are called normoxic dosimeters, because they can be prepared under normal atmospheric conditions, rather than in a glove box that excludes oxygen. In this review, an effort is made to explain some of the underlying chemical phenomena that affect dosimeter performance using THPC, and that lead to differences in behaviour between dosimeters made using the two types of monomer systems. Progress on the development of new more effective and less toxic dosimeters is also reported.

  5. Injectable biocompatible and biodegradable pH-responsive hollow particle gels containing poly(acrylic acid): the effect of copolymer composition on gel properties.

    Science.gov (United States)

    Halacheva, Silvia S; Adlam, Daman J; Hendow, Eseelle K; Freemont, Tony J; Hoyland, Judith; Saunders, Brian R

    2014-05-12

    The potential of various pH-responsive alkyl (meth)acrylate ester- and (meth)acrylic acid-based copolymers, including poly(methyl methacrylate-co-acrylic acid) (PMMA-AA) and poly(n-butyl acrylate-co-methacrylic acid) (PBA-MAA), to form pH-sensitive biocompatible and biodegradable hollow particle gel scaffolds for use in non-load-bearing soft tissue regeneration have been explored. The optimal copolymer design criteria for preparation of these materials have been established. Physical gels which are both pH- and redox-sensitive were formed only from PMMA-AA copolymers. MMA is the optimal hydrophobic monomer, whereas the use of various COOH-containing monomers, e.g., MAA and AA, will always induce a pH-triggered physical gelation. The PMMA-AA gels were prepared at physiological pH range from concentrated dispersions of swollen, hollow, polymer-based particles cross-linked with either cystamine (CYS) or 3,3'-dithiodipropionic acid dihydrazide (DTP). A linear relationship between particle swelling ratios, gel elasticity, and ductility was observed. The PMMA-AA gels with lower AA contents feature lower swelling ratios, mechanical strengths, and ductilities. Increasing the swelling ratio (e.g., through increasing AA content) decreased the intraparticle elasticity; however, intershell contact and gel elasticity were found to increase. The mechanical properties and performance of the gels were tuneable upon varying the copolymers' compositions and the structure of the cross-linker. Compared to PMMA-AA/CYS, the PMMA-AA/DTP gels were more elastic and ductile. The biodegradability and cytotoxicity of the new hollow particle gels were tested for the first time and related to their composition, mechanical properties, and morphology. The new PMMA-AA/CYS and PMMA-AA/DTP gels have shown good biocompatibility, biodegradability, strength, and interconnected porosity and therefore have good potential as a tissue repair agent.

  6. White-light-emitting supramolecular gels.

    Science.gov (United States)

    Praveen, Vakayil K; Ranjith, Choorikkat; Armaroli, Nicola

    2014-01-07

    Let there be light, let it be white: Recent developments in the use of chromophore-based gels as scaffolds for the assembly of white-light-emitting soft materials have been significant. The main advantage of this approach lies in the facile accommodation of selected luminescent components within the gel. Excitation-energy-transfer processes between these components ultimately generate the desired light output. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Sol-gel-state of hydrated zirconium dioxide

    International Nuclear Information System (INIS)

    Karakchiev, L.G.; Lyakhov, N.Z.

    1995-01-01

    The change in viscosity and density of a system in the course of sol-gel-xerogel has been traced. The size and molecular mass of particles in sol have been determined. Initial sol is practically a monodisperse system. Gel is a spatial net of similar particles. Reversible character of sol-gel transition with a change in water content in the system suggests instability of the bond between the particles in the structure of the solid state body formed. 11 refs.; 4 figs

  8. Molecular Gels Materials with Self-Assembled Fibrillar Networks

    CERN Document Server

    Weiss, Richard G

    2006-01-01

    Molecular gels and fibrillar networks – a comprehensive guide to experiment and theory Molecular Gels: Materials with Self-Assembled Fibrillar Networks provides a comprehensive treatise on gelators, especially low molecular-mass gelators (LMOGs), and the properties of their gels. The structures and modes of formation of the self-assembled fibrillar networks (SAFINs) that immobilize the liquid components of the gels are discussed experimentally and theoretically. The spectroscopic, rheological, and structural features of the different classes of LMOGs are also presented. Many examples of the application of the principal analytical techniques for investigation of molecular gels (including SANS, SAXS, WAXS, UV-vis absorption, fluorescence and CD spectroscopies, scanning electron, transmission electron and optical microscopies, and molecular modeling) are presented didactically and in-depth, as are several of the theories of the stages of aggregation of individual LMOG molecules leading to SAFINs. Several actua...

  9. DNA gel electrophoresis: the reptation model(s).

    Science.gov (United States)

    Slater, Gary W

    2009-06-01

    DNA gel electrophoresis has been the most important experimental tool to separate DNA fragments for several decades. The introduction of PFGE in the 1980s and capillary gel electrophoresis in the 1990s made it possible to study, map and sequence entire genomes. Explaining how very large DNA molecules move in a gel and why PFGE is needed to separate them has been an active field of research ever since the launch of the journal Electrophoresis. This article presents a personal and historical overview of the development of the theory of gel electrophoresis, focusing on the reptation model, the band broadening mechanisms, and finally the factors that limit the read length and the resolution of electrophoresis-based sequencing systems. I conclude with a short discussion of some of the questions that remain unanswered.

  10. Performance of Magnetic Filter for Separation of Magnetic Gel Particles

    OpenAIRE

    栗延, 俊太郎; 尾崎, 博明; 渡辺, 恒雄; クリノブ, シュンタロウ; オザキ, ヒロアキ; ワタナベ, ツネオ; Shuntaro, KURINOBU; Hiroaki, OZAKI; Tuneo, WATANABE

    2003-01-01

    We have developed a new wastewater treatment process using magnetic gel particles containing immobilized microorganisms and magnetic particles. The performance of magnetic gel particles using a magnetic filter is very important to control the process. In this study, the performance of a magnetic filter was studied for magnetic gel, particles. Agar particles containing magnetite particles were used as gel particles. The recovery and the relative retention area of magnetic gel particles on the ...

  11. Development of an injectable chitosan/marine collagen composite gel

    International Nuclear Information System (INIS)

    Wang Wei; Itoh, Soichiro; Aizawa, Tomoyasu; Demura, Makoto; Okawa, Atsushi; Sakai, Katsuyoshi; Ohkuma, Tsuneo

    2010-01-01

    A chitosan/marine-originated collagen composite has been developed. This composite gel was characterized and its biocompatibility, as well as an inflammatory reaction, was observed. The chitosan gel including N-3-carboxypropanoil-6-O-(carboxymethyl) chitosan of 3 mol%, 6-O-(carboxymethyl) chitosan of 62 mol% and 6-O-(carboxymethyl) chitin of 35 mol% was prepared and compounded with the salmon atelocollagen (SA) gel at different mixture ratios. The composite gels were injected subcutaneously in to the back of rats. The specimens were harvested for a histological survey as well as a tumor necrosis factor-alpha (TNF-α) assay by ELISA. The inflammatory cell infiltration and release of TNF-α were successively controlled low with the ratio of SA to chitosan at 10:90 or 20:80. The SA gel first, within 2 weeks, and then chitosan in the composite gel were slowly absorbed after implantation, followed by soft tissue formation. It is expected that this composite gel will be available as a carrier for tissue filler and drug delivery systems.

  12. A novel fibrin gel derived from hyaluronic acid-grafted fibrinogen

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chiung L; Chen, Hui W; Wang, Tzu C; Wang, Yng J, E-mail: wang@ym.edu.tw [Institute of Biomedical Engineering, National Yang Ming University, No. 155, Sec. 2, Li-Nung St., Shih-Pai, Taipei, Taiwan 112 (China)

    2011-04-15

    Fibrinogen is a major plasma protein that forms a three-dimensional fibrin gel upon being activated by thrombin. In this study, we report the synthesis and potential applications of hybrid molecules composed of fibrinogen coupled to the reducing ends of short-chain hyaluronic acids (sHAs) by reductive amination. The grafting of sHAs to fibrinogen was verified by analyzing particle size, zeta potential and gel-electrophoretic mobility of the hybrid molecules. The sHA-fibrinogen hybrid molecules with graft ratios (sHA/fibrinogen) of up to 6.5 retained the ability to form gels in response to thrombin activation. The sHA-fibrin gels were transparent in appearance and exhibited high water content, which were characteristics distinct from those of gels formed by mixtures of sHAs and fibrinogen. The potential applications of the sHA-fibrin gels were evaluated. The sHA-fibrinogen gel with a graft ratio of 3.6 (S3.6F) was examined for its ability to encapsulate and support the differentiation of ATDC5 chondrocyte-like cells. Compared with the fibrinogen-formed gel, cells cultured in the S3.6F gel exhibited increased lacunae formation; moreover, the abundance of cartilaginous extracellular matrix molecules and the expression of chondrocyte marker genes, such as aggrecan, collagen II and Sox9, were also significantly increased. Our data suggest that the three-dimensional gel formed by the sHA-fibrinogen hybrid is a better support than the fibrin gel for chondrogenesis induction.

  13. A novel fibrin gel derived from hyaluronic acid-grafted fibrinogen

    International Nuclear Information System (INIS)

    Yang, Chiung L; Chen, Hui W; Wang, Tzu C; Wang, Yng J

    2011-01-01

    Fibrinogen is a major plasma protein that forms a three-dimensional fibrin gel upon being activated by thrombin. In this study, we report the synthesis and potential applications of hybrid molecules composed of fibrinogen coupled to the reducing ends of short-chain hyaluronic acids (sHAs) by reductive amination. The grafting of sHAs to fibrinogen was verified by analyzing particle size, zeta potential and gel-electrophoretic mobility of the hybrid molecules. The sHA-fibrinogen hybrid molecules with graft ratios (sHA/fibrinogen) of up to 6.5 retained the ability to form gels in response to thrombin activation. The sHA-fibrin gels were transparent in appearance and exhibited high water content, which were characteristics distinct from those of gels formed by mixtures of sHAs and fibrinogen. The potential applications of the sHA-fibrin gels were evaluated. The sHA-fibrinogen gel with a graft ratio of 3.6 (S3.6F) was examined for its ability to encapsulate and support the differentiation of ATDC5 chondrocyte-like cells. Compared with the fibrinogen-formed gel, cells cultured in the S3.6F gel exhibited increased lacunae formation; moreover, the abundance of cartilaginous extracellular matrix molecules and the expression of chondrocyte marker genes, such as aggrecan, collagen II and Sox9, were also significantly increased. Our data suggest that the three-dimensional gel formed by the sHA-fibrinogen hybrid is a better support than the fibrin gel for chondrogenesis induction.

  14. Role of gel dosimeters in boron neutron capture therapy

    International Nuclear Information System (INIS)

    Khajeali, Azim; Farajollahi, Ali Reza; Khodadadi, Roghayeh; Kasesaz, Yaser; Khalili, Assef

    2015-01-01

    Gel dosimeters have acquired a unique status in radiotherapy, especially with the advent of the new techniques in which there is a need for three-dimensional dose measurement with high spatial resolution. One of the techniques in which the use of gel dosimeters has drawn the attention of the researchers is the boron neutron capture therapy. Exploring the history of gel dosimeters, this paper sets out to study their role in the boron neutron capture therapy dosimetric process. - Highlights: • Gel dosimeters have been investigated. • Conventional dosimetric proses of BNCT has been investigated. • Role of gel dosimeters in BNCT has been investigated

  15. Fast Processing of Sol-Gel TCO

    NARCIS (Netherlands)

    Deelen, J. van; Rem, M.; Arfsten, N.; Buskens, P.P.

    2016-01-01

    TCOs are usually deposited using sputtering or chemical vapor deposition, which have a yield of typically 50-75%. The sol gel method does not need low pressure and can be done with a high precursor yield in the range of 90 – 100%. Sol gel enables also the TCO function as a planarization or

  16. ANALISA DAYA SERAP SILIKA GEL BERBAHAN DASAR ABU SEKAM PADI

    Directory of Open Access Journals (Sweden)

    Hendriwan Fahmi

    2016-08-01

    Full Text Available Rice husk ash Silica Gel is aproduct which call be used in preventing the humidity by absorbing the water ion on the water andonthe air. This absorbing isbased onthe size, the composition and the total amount ofpolluter which contained on the Silica Gel. The purpose of making this silica gel is to seehow much thiskind of Silica Gel can absorb and compare it to the synthetic one,and also processing rise husk ashto be something useful, Ion water can be absorbed much more by using this natural silica gel if it is compared to the synthetic silica gel. This is because of its capable inabsorbing more –OHand O from water and air. Afterdoing a research with column method, silica gel was beingput in 50 ml water. Fromthis research, natural silica can absorb much more water (0.0010 gr/ml, 0.285 % water level ofweigh in comparing with synthetic one (0.008gr/ml with 0.248 %water level ofweight andsintering (0,007 gr/ml 0.253%water level and non-sintering silica gel contains 39.22 % weight of silica, 30.93 %weight of sintering silica gel, and 33.40 % of the synthetic. More silica and water level, means more total amount of absorbing. This silica gel application is considered with capability ofabsorbing andthe level of the water.

  17. Characterization of a humic gel synthesized from an activated epoxy silica gel

    International Nuclear Information System (INIS)

    Barbot, C.; Pieri, J.; Durand, J.P.; Goudard, F.; Czerwinski, K.; Vial, M.; Buckau, G.; Kim, J.I.; Moulin, V.

    2002-01-01

    Purified humic acid has been covalently bound on activated epoxy silica gel particles. Determination of physical properties and chemical properties was conducted in order to characterize the material at different stages of the preparation. FTIR spectra and the PEC of the surface bound humic acid is very similar to that of humic acid starting material. This shows that the humic acid was not deteriorated during the surface binding process. This humic gel can be used as an analogue for sediment associated humic acid, with the advantage that covalently bound humic acid does not desorb, and thus allows for simple species separation between non-complexed and humic bound metal ions in batch and column experiments

  18. Volume phase transitions of cholesteric liquid crystalline gels.

    Science.gov (United States)

    Matsuyama, Akihiko

    2015-05-07

    We present a mean field theory to describe anisotropic deformations of a cholesteric elastomer without solvent molecules and a cholesteric liquid crystalline gel immersed in isotropic solvents at a thermal equilibrium state. Based on the neoclassical rubber theory of nematic elastomers, we derive an elastic energy and a twist distortion energy, which are important to determine the shape of a cholesteric elastomer (or gel). We demonstrate that when the elastic energy dominates in the free energy, the cholesteric elastomer causes a spontaneous compression in the pitch axis and elongates along the director on the plane perpendicular to the pitch axis. Our theory can qualitatively describe the experimental results of a cholesteric elastomer. We also predict the first-order volume phase transitions and anisotropic deformations of a gel at the cholesteric-isotropic phase transition temperature. Depending on a chirality of a gel, we find a prolate or oblate shape of cholesteric gels.

  19. Volume phase transitions of cholesteric liquid crystalline gels

    Energy Technology Data Exchange (ETDEWEB)

    Matsuyama, Akihiko, E-mail: matuyama@bio.kyutech.ac.jp [Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Kawazu 680-4, Iizuka, Fukuoka 820-8502 (Japan)

    2015-05-07

    We present a mean field theory to describe anisotropic deformations of a cholesteric elastomer without solvent molecules and a cholesteric liquid crystalline gel immersed in isotropic solvents at a thermal equilibrium state. Based on the neoclassical rubber theory of nematic elastomers, we derive an elastic energy and a twist distortion energy, which are important to determine the shape of a cholesteric elastomer (or gel). We demonstrate that when the elastic energy dominates in the free energy, the cholesteric elastomer causes a spontaneous compression in the pitch axis and elongates along the director on the plane perpendicular to the pitch axis. Our theory can qualitatively describe the experimental results of a cholesteric elastomer. We also predict the first-order volume phase transitions and anisotropic deformations of a gel at the cholesteric-isotropic phase transition temperature. Depending on a chirality of a gel, we find a prolate or oblate shape of cholesteric gels.

  20. Laser CT evaluation on normoxic PAGAT gel dosimeter

    International Nuclear Information System (INIS)

    Kumar, D S; Samuel, E J J; Watanabe, Y

    2013-01-01

    Optical computed tomography has been shown to be a potentially useful imaging tool for the radiation therapy physicists. In radiation therapy, researchers have used optical CT for the readout of 3D dosimeters. The purpose of this paper is to describe the initial evaluation of a newly fabricated laser CT scanner for 3D gel dosimetry which works using the first generation principle. A normoxic PAGAT (Polyacrylamide Gelatin and Tetrakis) gel is used as a dosimeter for this analysis. When a laser passes through the gel phantom, absorption and scattering of photon take place. The optical attenuation coefficient of the laser can be obtained by measuring its intensity after passing through the gel by a sensor. The scanner motion is controlled by a computer program written in Microsoft Visual C++. Reconstruction and data analysis on the irradiated gel phantom is performed by suitable algorithm using Matlab software.

  1. Optical CT evaluation on normoxic polymer gel dosimeter

    International Nuclear Information System (INIS)

    Samuel, E. James Jebaseelan

    2013-01-01

    Optical computed tomography has been shown to be a potentially useful imaging tool for the radiation therapy physicists. In radiation therapy, researchers have used optical CT for the readout of 3D dosimeters. The purpose of this paper is to explicate the initial evaluation of a newly fabricated laser CT scanner for '3D gel dosimetry' which works in the first generation principle. The normoxic PAGAT (Polyacrylamide Gelatin and Tetrakis) gel is used as a dosimeter for this analysis. When laser passes through this gel phantom, absorption and scattering of photon take place. The optical attenuation coefficient of the laser can be obtained by measuring its intensity after passing through the gel by a sensor.The scanner motion is controlled by the program written in Microsoft Visual C++. Reconstruction and data analysis on the irradiated gel phantom is performed by suitable algorithm using Matlab software. (author)

  2. Sol-gel materials for optofluidics - process and applications

    DEFF Research Database (Denmark)

    Mikkelsen, Morten Bo Lindholm

    2011-01-01

    This Ph.D. thesis is concerned with the use of sol-gel materials in optofluidic applications and the physics of DNA molecules in nanoconfinement. The bottom-up formation of solid material, which is provided by the sol-gel process, enables control of the chemical composition and porosity...... of the material. At early stages of gelation, thin gel coatings can be structured by nanoimprint lithography, and purely inorganic silica materials can be obtained by subsequent thermal annealing. The sol-gel process thus constitutes a unique method for nanofabrication of silica materials of special properties....... In this work, sol-gel silica is introduced as a new material class for the fabrication of lab-on-a-chip devices for DNA analysis. An imprint process with a rigid, non-permeable stamp was developed, which enabled fabrication of micro- and nanofluidic silica channels in a single process step without use of any...

  3. Non-stationary heat transfer in gels applied to biotehnology

    Directory of Open Access Journals (Sweden)

    Pokusaev Boris

    2017-01-01

    Full Text Available Unsteady heat transfer in agarose gels of various concentrations was studied in order to make a breakthrough in the technology of 3-D additive bioprinting. Data on the kinetics of the phase transformation was obtained using spectroscopy as a function of temperature during the formation of agarose hydrogel. The dynamics of aging was investigated for gels of different densities. The time dependence of the structural changes was obtained. Particular attention was paid to the changes in the structure of the gel due to the processes of evaporation of the liquid during the gel formation and during long-term storage. Experiments were performed to determine the dynamics of the temperature fields simultaneously with heat flux measurements during the formation of agarose gels from different initial concentrations. A technique based on experimental data for the computations of the thermophysical coefficients of agarose gels was developed.

  4. A method for easily customizable gradient gel electrophoresis.

    Science.gov (United States)

    Miller, Andrew J; Roman, Brandon; Norstrom, Eric

    2016-09-15

    Gradient polyacrylamide gel electrophoresis is a powerful tool for the resolution of polypeptides by relative mobility. Here, we present a simplified method for generating polyacrylamide gradient gels for routine analysis without the need for specialized mixing equipment. The method allows for easily customizable gradients which can be optimized for specific polypeptide resolution requirements. Moreover, the method eliminates the possibility of buffer cross contamination in mixing equipment, and the time and resources saved with this method in place of traditional gradient mixing, or the purchase of pre-cast gels, are noteworthy given the frequency with which many labs use gradient gel SDS-PAGE. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Comparison effect of azithromycin gel 2% with clindamycin gel 1% in patients with acne.

    Science.gov (United States)

    Mokhtari, Fatemeh; Faghihi, Gita; Basiri, Akram; Farhadi, Sadaf; Nilforoushzadeh, Mohammadali; Behfar, Shadi

    2016-01-01

    Acne vulgaris is the most common skin disease. Local and systemic antimicrobial drugs are used for its treatment. But increasing resistance of Propionibacterium acnes to antibiotics has been reported. In a double-blind clinical trial, 40 patients with mild to moderate acne vulgaris were recruited. one side of the face was treated with Clindamycin Gel 1% and the other side with Azithromycin Topical Gel 2% BID for 8 weeks and then they were assessed. Average age was 21. 8 ± 7 years. 82.5% of them were female. Average number of papules, pustules and comedones was similarly reduced in both groups and, no significant difference was observed between the two groups (P > 0.05, repeated measurs ANOVA). The mean indexes of ASI and TLC also significantly decreased during treatment in both groups, no significant difference was observed between the two groups. (P > 0.05, repeated measurs ANOVA). Also, impact of both drugs on papules and pustules was 2-3 times greater than the effect on comedones. Average satisfaction score was not significant between the two groups (P = 0.6, repeated measurs ANOVA). finally, frequency distribution of complications was not significant between the two groups (P > 0.05, Fisher Exact test). Azithromycin gel has medical impact at least similar to Clindamycin Gel in treatment of mild to moderate acne vulgaris, and it may be consider as suitable drug for resistant acne to conventional topical therapy.

  6. Magneto-dependent stress relaxation of magnetorheological gels

    KAUST Repository

    Xu, Yangguang; Liu, Taixiang; Liao, G J; Lubineau, Gilles

    2017-01-01

    The stress relaxation behaviors of magnetorheological (MR) gels under stepwise shear loading are systematically investigated. The particle-enhanced effect, the magneto-induced effect, and the temperature-enhanced effect on the stress relaxation of MR gels are discussed. For further analysis of the magneto-induced stress relaxation mechanism in MR gels, a phenomenological model is established to describe the stress relaxation behavior of the matrix and the magnetic particle chains. All characteristic parameters introduced in the model, i.e. relaxation time, instantaneous modulus, and stable modulus, have well-defined physical meanings and are fitted based on the experimental results. The influence of each parameter on the macroscopic response is discussed and it is found that the relaxation stress induced by the magneto-mechanical coupling effect plays an important role in the stress relaxation process of MR gels.

  7. Magneto-dependent stress relaxation of magnetorheological gels

    KAUST Repository

    Xu, Yangguang

    2017-09-01

    The stress relaxation behaviors of magnetorheological (MR) gels under stepwise shear loading are systematically investigated. The particle-enhanced effect, the magneto-induced effect, and the temperature-enhanced effect on the stress relaxation of MR gels are discussed. For further analysis of the magneto-induced stress relaxation mechanism in MR gels, a phenomenological model is established to describe the stress relaxation behavior of the matrix and the magnetic particle chains. All characteristic parameters introduced in the model, i.e. relaxation time, instantaneous modulus, and stable modulus, have well-defined physical meanings and are fitted based on the experimental results. The influence of each parameter on the macroscopic response is discussed and it is found that the relaxation stress induced by the magneto-mechanical coupling effect plays an important role in the stress relaxation process of MR gels.

  8. Maize Arabinoxylan Gels as Protein Delivery Matrices

    Directory of Open Access Journals (Sweden)

    Ana Luisa Martínez-López

    2009-04-01

    Full Text Available The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v in the presence of insulin or β-lactoglobulin at 0.1% (w/v was investigated. Insulin and β-lacto-globulin did not modify either the gel elasticity (9 Pa or the cross-links content (0.03 and 0.015 mg di- and triferulic acids/mg arabinoxylan, respectively. The protein release capability of the gel was also investigated. The rate of protein release from gels was dependent on the protein molecular weight. The apparent diffusion coefficient was 0.99 × 10-7 and 0.79 × 10-7 cm2/s for insulin (5 kDa and β-lactoglobulin (18 kDa, respectively. The results suggest that maize bran arabinoxylan gels can be potential candidates for the controlled release of proteins.

  9. Pulsed field gel electrophoresis a practical guide

    CERN Document Server

    Birren, Bruce

    1993-01-01

    Pulsed Field Gel Electrophoresis: A Practical Guide is the first laboratory manual to describe the theory and practice of this technique. Based on the authors' experience developing pulsed field gel instruments and teaching procedures, this book provides everything a researcher or student needs to know in order to understand and carry out pulsed field gel experiments. Clear, well-tested protocols assume only that users have a basic familiarity with molecular biology. Thorough coverage of useful data, theory, and applications ensures that this book is also a lasting resource for more adv

  10. SPI Conformance Gel Applications in Geothermal Zonal Isolation

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Lyle [Clean Tech Innovations, Bartlesville, OK (United States)

    2017-08-08

    Zonal isolation in geothermal injection and producing wells is important while drilling the wells when highly fractured geothermal zones are encountered and there is a need to keep the fluids from interfering with the drilling operation. Department of Energy’s (DOE) Energy Efficiency and Renewable Energy (EERE) objectives are to advance technologies to make it more cost effective to develop, produce, and monitor geothermal reservoirs and produce geothermal energy. Thus, zonal isolation is critical to well cost, reservoir evaluation and operations. Traditional cementing off of the lost circulation or thief zones during drilling is often done to stem the drilling mud losses. This is an expensive and generally unsuccessful technique losing the potential of the remaining fracture system. Selective placement of strong SPI gels into only the offending fractures can maintain and even improve operational efficiency and resource life. The SPI gel system is a unique silicate based gel system that offers a promising solution to thief zones and conformance problems with water and CO2 floods and potentially geothermal operations. This gel system remains a low viscosity fluid until an initiator (either internal such as an additive or external such as CO2) triggers gelation. This is a clear improvement over current mechanical methods of using packers, plugs, liners and cementing technologies that often severely damage the highly fractured area that is isolated. In the SPI gels, the initiator sets up the fluid into a water-like (not a precipitate) gel and when the isolated zone needs to be reopened, the SPI gel may be removed with an alkaline solution without formation damage occurring. In addition, the SPI gel in commercial quantities is expected to be less expensive than competing mechanical systems and has unique deep placement possibilities. This project seeks to improve upon the SPI gel integrity by modifying the various components to impart temperature stability for use in

  11. Charge-regularized swelling kinetics of polyelectrolyte gels: Elasticity and diffusion

    Science.gov (United States)

    Sen, Swati; Kundagrami, Arindam

    2017-11-01

    We apply a recently developed method [S. Sen and A. Kundagrami, J. Chem. Phys. 143, 224904 (2015)], using a phenomenological expression of osmotic stress, as a function of polymer and charge densities, hydrophobicity, and network elasticity for the swelling of spherical polyelectrolyte (PE) gels with fixed and variable charges in a salt-free solvent. This expression of stress is used in the equation of motion of swelling kinetics of spherical PE gels to numerically calculate the spatial profiles for the polymer and free ion densities at different time steps and the time evolution of the size of the gel. We compare the profiles of the same variables obtained from the classical linear theory of elasticity and quantitatively estimate the bulk modulus of the PE gel. Further, we obtain an analytical expression of the elastic modulus from the linearized expression of stress (in the small deformation limit). We find that the estimated bulk modulus of the PE gel decreases with the increase of its effective charge for a fixed degree of deformation during swelling. Finally, we match the gel-front locations with the experimental data, taken from the measurements of charged reversible addition-fragmentation chain transfer gels to show an increase in gel-size with charge and also match the same for PNIPAM (uncharged) and imidazolium-based (charged) minigels, which specifically confirms the decrease of the gel modulus value with the increase of the charge. The agreement between experimental and theoretical results confirms general diffusive behaviour for swelling of PE gels with a decreasing bulk modulus with increasing degree of ionization (charge). The new formalism captures large deformations as well with a significant variation of charge content of the gel. It is found that PE gels with large deformation but same initial size swell faster with a higher charge.

  12. Cost Analysis of Treating Neonatal Hypoglycemia with Dextrose Gel.

    Science.gov (United States)

    Glasgow, Matthew J; Harding, Jane E; Edlin, Richard

    2018-04-03

    To evaluate the costs of using dextrose gel as a primary treatment for neonatal hypoglycemia in the first 48 hours after birth compared with standard care. We used a decision tree to model overall costs, including those specific to hypoglycemia monitoring and treatment and those related to the infant's length of stay in the postnatal ward or neonatal intensive care unit, comparing the use of dextrose gel for treatment of neonatal hypoglycemia with placebo, using data from the Sugar Babies randomized trial. Sensitivity analyses assessed the impact of dextrose gel cost, neonatal intensive care cost, cesarean delivery rate, and costs of glucose monitoring. In the primary analysis, treating neonatal hypoglycemia using dextrose gel had an overall cost of NZ$6863.81 and standard care (placebo) cost NZ$8178.25; a saving of NZ$1314.44 per infant treated. Sensitivity analyses showed that dextrose gel remained cost saving with wide variations in dextrose gel costs, neonatal intensive care unit costs, cesarean delivery rates, and costs of monitoring. Use of buccal dextrose gel reduces hospital costs for management of neonatal hypoglycemia. Because it is also noninvasive, well tolerated, safe, and associated with improved breastfeeding, buccal dextrose gel should be routinely used for initial treatment of neonatal hypoglycemia. Australian New Zealand Clinical Trials Registry: ACTRN12608000623392. Copyright © 2018 Elsevier Inc. All rights reserved.

  13. Electroblotting from Polyacrylamide Gels.

    Science.gov (United States)

    Goldman, Aaron; Ursitti, Jeanine A; Mozdzanowski, Jacek; Speicher, David W

    2015-11-02

    Transferring proteins from polyacrylamide gels onto retentive membranes is now primarily used for immunoblotting. A second application that was quite common up to about a decade ago was electroblotting of proteins for N-terminal and internal sequencing using Edman chemistry. This unit contains procedures for electroblotting proteins from polyacrylamide gels onto a variety of membranes, including polyvinylidene difluoride (PVDF) and nitrocellulose. In addition to the commonly used tank or wet transfer system, protocols are provided for electroblotting using semidry and dry systems. This unit also describes procedures for eluting proteins from membranes using detergents or acidic extraction with organic solvents for specialized applications. Copyright © 2015 John Wiley & Sons, Inc.

  14. Preparation and Properties of Polyester-Based Nanocomposite Gel Coat System

    Directory of Open Access Journals (Sweden)

    P. Jawahar

    2006-01-01

    Full Text Available Nanocomposite gel coat system is prepared using unsaturated polyester resin with aerosil powder, CaCO3, and organoclay. The influence of organoclay addition on mechanical and water barrier properties of gel coat system is studied for different amount (1, 2, and 3 wt % of organoclay. The nanolevel incorporation of organoclay improves the mechanical and water barrier properties of nanocomposite gel coat system. The nanocomposite gel coat system exhibits 55% improvement in tensile modulus and 25% improvement in flexural modulus. There is a 30% improvement in impact property of nanocomposite gel coat system. The dynamic mechanical analysis shows a slight increase in glass transition temperature for nanocomposite gel coat system.

  15. Radiation effect on polystyrene deposited and grafted on silica gel

    International Nuclear Information System (INIS)

    Kusama, Y.; Udagawa, A.; Takehisa, M.

    1978-01-01

    The effect of radiation on polystyrene was studied in the presence and absence of silica gel by molecular weight measurement with gel permeation chromatography (GPC). Polystyrene crosslinked under vacuum in the absence of silica gel, but it either crosslinked or degraded by radiation, depending on the molecular weight of the polymer in the presence of silica gel. part of the deposited polymer bonded to silica gel by radiation; the G value for graft-chain formation is in the range of 0.01 to 0.1. Irradiation of polystyrene grafted on silica gel resulted in degradation of the graft chain because of the transfer of energy from silica gel. The G value for main chain scission was about 2 when graft polymer was irradiated in the absence of homopolymer. The degradation of graft polymer was suppressed when the polymer was irradiated in the presence of homopolymer, and the amount of unextractable polymer from silica gel increased with increasing irradiation. This adds evidence to the estimation that an increase in grafting percent coupled with a slight decrease in molecular weight at a later stage of radiation-induced polymerization of styrene adsorbed on slica gel is due to a secondary effect of radiation on the polymer

  16. A zwitterionic gel electrolyte for efficient solid-state supercapacitors

    Science.gov (United States)

    Peng, Xu; Liu, Huili; Yin, Qin; Wu, Junchi; Chen, Pengzuo; Zhang, Guangzhao; Liu, Guangming; Wu, Changzheng; Xie, Yi

    2016-01-01

    Gel electrolytes have attracted increasing attention for solid-state supercapacitors. An ideal gel electrolyte usually requires a combination of advantages of high ion migration rate, reasonable mechanical strength and robust water retention ability at the solid state for ensuring excellent work durability. Here we report a zwitterionic gel electrolyte that successfully brings the synergic advantages of robust water retention ability and ion migration channels, manifesting in superior electrochemical performance. When applying the zwitterionic gel electrolyte, our graphene-based solid-state supercapacitor reaches a volume capacitance of 300.8 F cm−3 at 0.8 A cm−3 with a rate capacity of only 14.9% capacitance loss as the current density increases from 0.8 to 20 A cm−3, representing the best value among the previously reported graphene-based solid-state supercapacitors, to the best of our knowledge. We anticipate that zwitterionic gel electrolyte may be developed as a gel electrolyte in solid-state supercapacitors. PMID:27225484

  17. One plunge or two?--hand disinfection with alcohol gel.

    Science.gov (United States)

    Macdonald, Duncan J M; Mckillop, Elisabeth C A; Trotter, Sylvia; Gray, Alastair J R

    2006-04-01

    To compare health care workers' hand surface coverage using two different volumes of alcohol gel for hand disinfection. and methods. A total of 84 members of staff in our hospital were studied. Subjects were asked to disinfect their hands with alcohol gel containing a clear fluorescent substance. Performance was assessed by using UV light to identify areas which had been missed, and the total surface area missed was calculated. A total of 42 subjects received 3.5 ml of alcohol gel, and 42 age-, sex-, and job-matched subjects received 1.75 ml of alcohol gel. Significantly less area was missed when hand disinfecting with double the volume of alcohol gel; 1.23 versus 6.35% surface area was missed (P disinfection significantly improves the efficiency of coverage of the hands with alcohol gel. This may result in lower bacterial count on the hands and may reduce the spread of nosocomial infections including that of methicillin-resistant Staphylococcus aureus.

  18. PREPARATION AND PROPERTIES OF COMPOUND ARNEBIAE RADIX MICROEMULSION GEL.

    Science.gov (United States)

    Chen, Jing; He, Yanping; Gao, Ting; Zhang, Licheng; Zhao, Yuna

    2017-01-01

    Compound Arnebiae radix oil has been clinically applied to treat burns and scalds for a long time. However, it is unstable and inconvenient to use. The aim of this study was to prepare a compound Arnebiae radix microemulsion gel for transdermal delivery system and evaluate its characteristics. Based on the solubility of Shikonin, the active component of Arnebiae radix and the results of phase studies, adequate ratio of each component in microemulsion was determined. The optimized microemulsion gel was prepared using Carbomer 940. The gels were characterized in terms of appearance, preliminary stability test and the content of Shikonin in the compound Arnebiae radix microemulsion gel with HPLC analysis. The optimized conditions for preparing microemulsion were Tween-80, glycerin, isopropyl myristate (IPM) with the ratio of 6:3:2. The optimal microemulsion gel was obtained with Carbomer 940 (1.0%). The prepared compound Arnebiae radix microemulsion gel showed good stability over time. It is more convenience in application than the previous used formulations.

  19. The Influence of Microgravity on Silica Sol-Gel Formation

    Science.gov (United States)

    Sibille, L.; Smith, D. D.; Cronise, R.; Hunt, A. J.; Wolfe, D. B.; Snow, L. A.; Oldenberg, S.; Halas, N.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We discuss space-flight experiments involving the growth of silica particles and gels. The effect of microgravity on the growth of silica particles via the sol-gel route is profound. In four different recipes spanning a large range of the parameter space that typically produces silica nanoparticles in unit-gravity, low-density gel structures were instead formed in microgravity. The particles that did form were generally smaller and more polydisperse than those grown on the ground. These observations suggest that microgravity reduces the particle growth rate, allowing unincorporated species to form aggregates and ultimately gel. Hence microgravity favors the formation of more rarefied structures, providing a bias towards diffusion-limited cluster-cluster aggregation. These results further suggest that in unit gravity, fluid flows and sedimentation can significantly perturb sol-gel substructures prior to gelation and these deleterious perturbations may be "frozen" into the resulting microstructure. Hence, sol-gel pores may be expected to be smaller, more uniform, and less rough when formed in microgravity.

  20. Bioactive materials for biomedical applications using sol-gel technology

    International Nuclear Information System (INIS)

    Gupta, Radha; Kumar, Ashok

    2008-01-01

    This review paper focuses on the sol-gel technology that has been applied in many of the potential research areas and highlights the importance of sol-gel technology for preparing bioactive materials for biomedical applications. The versatility of sol-gel chemistry enables us to manipulate the characteristics of material required for particular applications. Sol-gel derived materials have proved to be good biomaterials for coating films and for the construction of super-paramagnetic nanoparticles, bioactive glasses and fiberoptic applicators for various biomedical applications. The introduction of the sol-gel route in a conventional method of preparing implants improves the mechanical strength, biocompatibility and bioactivity of scaffolds and prevents corrosion of metallic implants. The use of organically modified silanes (ORMOSILS) yields flexible and bioactive materials for soft and hard tissue replacement. A novel approach of nitric-oxide-releasing sol-gels as antibacterial coatings for reducing the infection around orthopedic implants has also been discussed

  1. Sol-gel Technology and Advanced Electrochemical Energy Storage Materials

    Science.gov (United States)

    Chu, Chung-tse; Zheng, Haixing

    1996-01-01

    Advanced materials play an important role in the development of electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. The sol-gel process is a versatile solution for use in the fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. This processing technique is particularly useful in producing porous materials with high surface area and low density, two of the most desirable characteristics for electrode materials. In addition,the porous surface of gels can be modified chemically to create tailored surface properties, and inorganic/organic micro-composites can be prepared for improved material performance device fabrication. Applications of several sol-gel derived electrode materials in different energy storage devices are illustrated in this paper. V2O5 gels are shown to be a promising cathode material for solid state lithium batteries. Carbon aerogels, amorphous RuO2 gels and sol-gel derived hafnium compounds have been studied as electrode materials for high energy density and high power density electrochemical capacitors.

  2. Current and future possibilities of sol-gel process

    International Nuclear Information System (INIS)

    Sakka, Sumio

    2004-01-01

    The sol-gel method is characterized by the low temperature processing. Since this method starts from solutions, the product is essentially nanomaterials. So far, various kinds of microstructures, including dense, porous, hybrid, amorphous and crystalline microstructures have been realized. Accordingly, sol-gel materials cover a wide range of functions, such as optical, electronic, mechanical, chemical and bio-functions. Future perspectives of the sol-gel method are described in the article. (author)

  3. Gel network shampoo formulation and hair health benefits.

    Science.gov (United States)

    Marsh, J M; Brown, M A; Felts, T J; Hutton, H D; Vatter, M L; Whitaker, S; Wireko, F C; Styczynski, P B; Li, C; Henry, I D

    2017-10-01

    The objective of this work was to create a shampoo formula that contains a stable ordered gel network structure that delivers fatty alcohols inside hair. X-ray diffraction (SAXS and WAXS), SEM and DSC have been used to confirm formation of the ordered Lβ gel network with fatty alcohol (cetyl and stearyl alcohols) and an anionic surfactant (SLE1S). Micro-autoradiography and extraction methods using GC-MS were used to confirm penetration of fatty alcohols into hair, and cyclic fatigue testing was used to measure hair strength. In this work, evidence of a stable Lβ ordered gel network structure created from cetyl and stearyl alcohols and anionic surfactant (SLE1S) is presented, and this is confirmed via scanning electron microscopy images showing lamella layers and differential scanning calorimetry (DSC) showing new melting peaks vs the starting fatty alcohols. Hair washed for 16 repeat cycles with this shampoo showed penetration of fatty alcohols from the gel network into hair as confirmed by a differential extraction method with GC-MS and by radiolabelling of stearyl alcohol and showing its presence inside hair cross-sections. The gel network role in delivering fatty alcohol inside hair is demonstrated by comparing with a shampoo with added fatty alcohol not in an ordered gel network structure. The hair containing fatty alcohol was measured via the Dia-stron cyclic fatigue instrument and showed a significantly higher number of cycles to break vs control. The formation of a stable gel network was confirmed in the formulated shampoo, and it was demonstrated that this gel network is important to deliver cetyl and stearyl alcohols into hair. The presence of fatty alcohol inside hair was shown to deliver a hair strength benefit via cyclic fatigue testing. © 2017 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

  4. Kinetics of swelling of polyelectrolyte gels: Fixed degree of ionization

    Science.gov (United States)

    Sen, Swati; Kundagrami, Arindam

    2015-12-01

    The swelling kinetics of uncharged and charged polymer (polyelectrolyte) gels in salt-free conditions is studied in one dimension by solving the constitutive equation of motion (Newton's law for the elementary gel volume) of the displacement variable by two theoretical methods: one in which the classical definition of stress is used with the bulk modulus taken as a parameter, and the other in which a phenomenological expression of the osmotic stress as a function of polymer density and degree of ionization is taken as an input to the dynamics. The time-evolution profiles for spatially varying polymer density and stress, along with the location of the gel-solvent interface, are obtained from the two methods. We show that both the polymer density (volume fraction) and stress inside the gel follow expected behaviours of being maximum for the uniformly shrunken gel, and relaxing slowly to the lowest values as the gel approaches equilibrium. We further show that, by comparing the temporal profiles of the gel-solvent interface and other variables between the two methods, one may attempt to assign an effective bulk modulus to the polyelectrolyte gel as a function of the degree of ionization and other parameters of the gel such as hydrophobicity, cross-link density, and the temperature. The major result we get is that the effective bulk modulus of a polyelectrolyte gel increases monotonically with its degree of ionization. In the process of identifying the parameters for a monotonic swelling, we calculated using a well-known expression of the free energy the equilibrium results of two-phase co-existence and the critical point of a polyelectrolyte gel with a fixed degree of ionization.

  5. Sol-gel process for the manufacture of high power switches

    Science.gov (United States)

    Landingham, Richard L.; Satcher, Jr, Joe; Reibold, Robert

    2016-09-27

    According to one embodiment, a photoconductive semiconductor switch includes a structure of nanopowder of a high band gap material, where the nanopowder is optically transparent, and where the nanopowder has a physical characteristic of formation from a sol-gel process. According to another embodiment, a method includes mixing a sol-gel precursor compound, a hydroxy benzene and an aldehyde in a solvent thereby creating a mixture, causing the mixture to gel thereby forming a wet gel, drying the wet gel to form a nanopowder, and applying a thermal treatment to form a SiC nanopowder.

  6. Buckling of paramagnetic chains in soft gels

    Science.gov (United States)

    Huang, Shilin; Pessot, Giorgio; Cremer, Peet; Weeber, Rudolf; Holm, Christian; Nowak, Johannes; Odenbach, Stefan; Menzel, Andreas M.; Auernhammer, Günter K.

    We study the magneto-elastic coupling behavior of paramagnetic chains in soft polymer gels exposed to external magnetic fields. To this end, a laser scanning confocal microscope is used to observe the morphology of the paramagnetic chains together with the deformation field of the surrounding gel network. The paramagnetic chains in soft polymer gels show rich morphological shape changes under oblique magnetic fields, in particular a pronounced buckling deformation. The details of the resulting morphological shapes depend on the length of the chain, the strength of the external magnetic field, and the modulus of the gel. Based on the observation that the magnetic chains are strongly coupled to the surrounding polymer network, a simplified model is developed to describe their buckling behavior. A coarse-grained molecular dynamics simulation model featuring an increased matrix stiffness on the surfaces of the particles leads to morphologies in agreement with the experimentally observed buckling effects.

  7. Structure of chitosan thermosensitive gels containing graphene oxide

    Science.gov (United States)

    Tylman, Michał; Pieklarz, Katarzyna; Owczarz, Piotr; Maniukiewicz, Waldemar; Modrzejewska, Zofia

    2018-06-01

    The supramolecular hydrogels of chitosan and graphene oxide (GO) have been prepared at temperature of the human body, by controlling the concentration of GO and ratio of chitosan to GO. During the preparation of gels the sodium β-glycerophosphate (Na-β-GP) was used as a neutralizing agent. The structure of obtained gels was determined on the basis of FTIR spectra and XRD diffraction patterns. The results of structural studies have been referenced to gels without graphene oxide. It was found that the gels crystalline structure after the addition of GO does not change. The XRD diffraction patterns are characterized by a number of peaks associated with precipitated NaCl during drying and presence of sodium β-glycerophosphate.

  8. Effect of temperature on internal structure of uranyl gels

    International Nuclear Information System (INIS)

    Landspersky, H.; Urbanek, V.

    1983-01-01

    Tempering freshly prepared uranyl gel serves the homogenization of the volume of the individual spheres and the whole volume of the processed material. Tempering is carried out at a temperature of 90 degC in a special countercurrent through-flow column. The tempered gel particles were analyzed for specific surface and porosity using different methods, subjected to phase analysis, and the crystallite mean size was determined. It was found that the quality of the final gel depends on the residence time in the tempering column. Gel recrystallization probably takes place during tempering leading to stress and cracks which in the final stage lead to the disintegration of the xerogel. Maximum permissible gel residence time in the tempering column is 15 mins. (M.D.)

  9. Effect of DCCA on synthesis of inorganic mesoporous gels

    International Nuclear Information System (INIS)

    Nemancha, A.R.

    2004-01-01

    Full text.The porous texture of the monolith inorganic gels plays an important role in the utilization of porous material by control of several properties such as gas diffusion, thermal stability, mechanical strength. the sol gel process provides many possibilities to manufacture porous material with extremely low concentration of impurities at low sinter temperature. The serious problem in the production of the monolith gels is fracture and crack formation which may occur in the conversion of the wet gels to dry gels. This phenomenon is probably due to the capillary forces which appear during the drying steps. in order to reduce the effect of capillary forces a number of methods were applied (hyper critic drying, organic DCCAs). The purpose of the present work, is to understand the chemical changes that result from adding formamide as drying control chemical additives DCCA to the colloidal silica sols in the presence of acid catalyst. Fourier Transformed Infrared spectroscopy and Raman spectroscopy were used to investigate the influence of formamide on gel formation. The Nitrogen adsorption-desorption technique is used to investigate the effect of formamide on gel texture. The results show that the gels with formamide are monolith and obtained during a short time of gelling reaction, the silica particles link formation depend strongly on the formamide concentration. the BET and BJH results show that the presence of formamide promotes the creation of meso porous texture depending on formamide/silica molar ratio in the starting sol. The maximum average diameter of the obtained gel reaches a value close to 25 nm with a bulk density equal to 1.1 g/cm 3

  10. When less is more: Psychometric properties of Norwegian short-forms of the Ambivalent Sexism Scales (ASI and AMI) and the Illinois Rape Myth Acceptance (IRMA) Scale.

    Science.gov (United States)

    Bendixen, Mons; Kennair, Leif Edward Ottesen

    2017-12-01

    This paper reports on the development and the psychometric properties of short forms of Ambivalent Sexism Scales toward women (ASI; Glick & Fiske, 1996) and men (AMI; Glick & Fiske, 1999), and a scale measuring rape stereotypes (IRMA; McMahon & Farmer, 2011). The short form AMI/ASI were applied for examining gender and educational differences in university students (N = 512) and in high school students (N = 1381), and for predicting individual differences in rape stereotypes in the latter. The short forms demonstrated good to excellent psychometric properties across samples of emerging adults. Relative to female students, male students reported markedly more hostility toward women and more stereotypical beliefs about rape. Despite sampling from a highly gender egalitarian and secular culture, these gender differences are on a par with those reported internationally. Rape stereotypes were predicted by sexism in high school students. Additional predictors were educational program, relationship status, and acceptance of derogatory sexual slurs. The paper questions the validity of separate constructs for benevolent sexism toward women versus men. The short form versions of the scales may substitute the original versions in future research, and help prevent attrition while measuring the same constructs. © 2017 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  11. Sol-gel-based biosensing applied to medicinal science.

    Science.gov (United States)

    Moreira, Felismina T C; Moreira-Tavares, Ana P; Sales, M Goreti F

    2015-01-01

    Biosensors have opened new horizons in biomedical analysis, by ensuring increased assay speed and flexibility, and allowing point-of-care applications, multi-target analyses, automation and reduced costs of testing. This has been a result of many studies merging nanotechnology with biochemistry over the years, thereby enabling the creation of more suitable environments to biological receptors and their substitution by synthetic analogue materials. Sol-gel chemistry, among other materials, is deeply involved in this process. Sol-gel processing allows the immobilization of organic molecules, biomacromolecules and cells maintaining their properties and activities, permitting their integration into different transduction devices, of electrochemical or optical nature, for single or multiple analyses. Sol-gel also allows to the production of synthetic materials mimicking the activity of natural receptors, while bringing advantages, mostly in terms of cost and stability. Moreover, the biocompatibility of sol-gel materials structures of biological nature allowed the use of these materials in emerging in vivo applications. In this chapter, biosensors for biomedical applications based on sol-gel derived composites are presented, compared and described, along with current emerging applications in vivo, concerning drug delivery or biomaterials. Sol-gel materials are shown as a promising tool for current, emerging and future medical applications.

  12. Profile of acute myocardial infarction (ami) in pakistan

    International Nuclear Information System (INIS)

    Jafary, M.H.; Samad, A.; Ishaq, M.; Jawaid, S.A.; Vohra, E.A.

    2007-01-01

    While doing the study on Aspirin Awareness and Usage (AAUS) in cases of Acute Coronary Syndrome (ACS), AAUS study Group designed the protocol to include the profile of patients presenting with symptoms of ACS and in the light of that also reviewed the available data in South Asian population. A prospective study was carried out in 17 coronary care units (CCUs) in all 4 provinces of Pakistan. Patients included were males and females of all age groups presenting with chest pain, diagnosed to have Coronary Artery Disease (CAD) and categorized into Unstable Angina (USA), STEMI or NSTEMI, based on clinical, ECG and enzymatic criteria. The risk factors, family history, dietary history, time to reach ER after the onset of symptoms, management of ACS in CCU and outcome of treatment were recorded. A total of 1,527 patients presented to the Emergency Room (ER) with chest pain but around 1400 patients were evaluable. The majority (68%) were males. The mean age of all patients was 52.2+-10.7 years. 28.3% patients were <45 years. Average time to presentation at ER was 13.2+-6.2 hours. 92.7% patients presented with chest pain. More than half the patients had hypertension (55.2%) and or smoking (52%) as the risk factors while 37.2 % had diabetes and 18.2% had hyperlipidemia. Hypertension (52.7%), IHD (44%) and Diabetes (36.2%) figured prominently in the family history. USA and STEMI were the major types of ACS (43.0% and 40.5% respectively). At discharge 67.8% of patients were stable without symptoms, 13.3% were stable but with symptoms, 16.4% were referred for further investigations and 2.5% had died. The review of the available data in Pakistan, supported by the present study in a cohort of 1400 patients from 17 CCUs in the country, the emerging profile of patients with AMI is that the majority are male, relatively younger as compared to Western population, have smoking and hypertension followed by diabetes as the major risk factors. USA and STEMI are the dominant types of ACS

  13. Photopatterned free-standing polyacrylamide gels for microfluidic protein electrophoresis.

    Science.gov (United States)

    Duncombe, Todd A; Herr, Amy E

    2013-06-07

    Designed for compatibility with slab-gel polyacrylamide gel electrophoresis (PAGE) reagents and instruments, we detail development of free-standing polyacrylamide gel (fsPAG) microstructures supporting electrophoretic performance rivalling that of microfluidic platforms. For the protein electrophoresis study described here, fsPAGE lanes are comprised of a sample reservoir and contiguous separation gel. No enclosed microfluidic channels are employed. The fsPAG devices (120 μm tall) are directly photopatterned atop of and covalently attached to planar polymer or glass surfaces. Leveraging the fast prototype-test cycle - significantly faster than mold based fabrication techniques - we optimize the fsPAG architecture to minimize injection dispersion for rapid (prototyping of the fsPAGE provides researchers a powerful tool for developing custom analytical assays. We highlight the utility of assay customization by fabricating a polyacrylamide gel with a spatial pore-size distribution and demonstrate the resulting enhancement in separation performance over a uniform gel. Further, we up-scale from a unit separation to an array of 96 concurrent fsPAGE assays in 10 min run time driven by one electrode pair. The fsPAG array layout matches that of a 96-well plate to facilitate integration of the planar free standing gel array with multi-channel pipettes while remaining compatible with conventional slab-gel PAGE reagents, such as staining for label-free protein detection. Notably, the entire fsPAGE workflow from fabrication, to operation, and readout uses readily available materials and instruments - making this technique highly accessible.

  14. Serum release boosts sweetness intensity in gels

    NARCIS (Netherlands)

    Sala, G.; Stieger, M.A.; Velde, van de F.

    2010-01-01

    This paper describes the effect of serum release on sweetness intensity in mixed whey protein isolate/gellan gum gels. The impact of gellan gum and sugar concentration on microstructure, permeability, serum release and large deformation properties of the gels was determined. With increasing gellan

  15. Dosimetric evaluation of a novel polymer gel dosimeter for proton therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zeidan, O. A.; Sriprisan, S. I.; Lopatiuk-Tirpak, O.; Kupelian, P. A.; Meeks, S. L.; Hsi, W. C.; Li, Z.; Palta, J. R.; Maryanski, M. J. [M. D. Anderson Cancer Center Orlando, Orlando, Florida 32806 (United States); University of Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States); MGS Research, Inc., Madison, Connecticut 06443 (United States)

    2010-05-15

    Purpose: The aim of this study is to evaluate the dosimetric performance of a newly developed proton-sensitive polymer gel formulation for proton therapy dosimetry. Methods: Using passive scattered modulated and nonmodulated proton beams, the dose response of the gel was assessed. A next-generation optical CT scanner is used as the readout mechanism of the radiation-induced absorbance in the gel medium. Comparison of relative dose profiles in the gel to ion chamber profiles in water is performed. A simple and easily reproducible calibration protocol is established for routine gel batch calibrations. Relative stopping power ratio measurement of the gel medium was performed to ensure accurate water-equivalent depth dose scaling. Measured dose distributions in the gel were compared to treatment planning system for benchmark irradiations and quality of agreement is assessed using clinically relevant gamma index criteria. Results: The dosimetric response of the gel was mapped up to 600 cGy using an electron-based calibration technique. Excellent dosimetric agreement is observed between ion chamber data and gel. The most notable result of this work is the fact that this gel has no observed dose quenching in the Bragg peak region. Quantitative dose distribution comparisons to treatment planning system calculations show that most (>97%) of the gel dose maps pass the 3%/3 mm gamma criterion. Conclusions: This study shows that the new proton-sensitive gel dosimeter is capable of reproducing ion chamber dose data for modulated and nonmodulated Bragg peak beams with different clinical beam energies. The findings suggest that the gel dosimeter can be used as QA tool for millimeter range verification of proton beam deliveries in the dosimeter medium.

  16. Dosimetric evaluation of a novel polymer gel dosimeter for proton therapy

    International Nuclear Information System (INIS)

    Zeidan, O. A.; Sriprisan, S. I.; Lopatiuk-Tirpak, O.; Kupelian, P. A.; Meeks, S. L.; Hsi, W. C.; Li, Z.; Palta, J. R.; Maryanski, M. J.

    2010-01-01

    Purpose: The aim of this study is to evaluate the dosimetric performance of a newly developed proton-sensitive polymer gel formulation for proton therapy dosimetry. Methods: Using passive scattered modulated and nonmodulated proton beams, the dose response of the gel was assessed. A next-generation optical CT scanner is used as the readout mechanism of the radiation-induced absorbance in the gel medium. Comparison of relative dose profiles in the gel to ion chamber profiles in water is performed. A simple and easily reproducible calibration protocol is established for routine gel batch calibrations. Relative stopping power ratio measurement of the gel medium was performed to ensure accurate water-equivalent depth dose scaling. Measured dose distributions in the gel were compared to treatment planning system for benchmark irradiations and quality of agreement is assessed using clinically relevant gamma index criteria. Results: The dosimetric response of the gel was mapped up to 600 cGy using an electron-based calibration technique. Excellent dosimetric agreement is observed between ion chamber data and gel. The most notable result of this work is the fact that this gel has no observed dose quenching in the Bragg peak region. Quantitative dose distribution comparisons to treatment planning system calculations show that most (>97%) of the gel dose maps pass the 3%/3 mm gamma criterion. Conclusions: This study shows that the new proton-sensitive gel dosimeter is capable of reproducing ion chamber dose data for modulated and nonmodulated Bragg peak beams with different clinical beam energies. The findings suggest that the gel dosimeter can be used as QA tool for millimeter range verification of proton beam deliveries in the dosimeter medium.

  17. DNA DAMAGE QUANTITATION BY ALKALINE GEL ELECTROPHORESIS.

    Energy Technology Data Exchange (ETDEWEB)

    SUTHERLAND,B.M.; BENNETT,P.V.; SUTHERLAND, J.C.

    2004-03-24

    Physical and chemical agents in the environment, those used in clinical applications, or encountered during recreational exposures to sunlight, induce damages in DNA. Understanding the biological impact of these agents requires quantitation of the levels of such damages in laboratory test systems as well as in field or clinical samples. Alkaline gel electrophoresis provides a sensitive (down to {approx} a few lesions/5Mb), rapid method of direct quantitation of a wide variety of DNA damages in nanogram quantities of non-radioactive DNAs from laboratory, field, or clinical specimens, including higher plants and animals. This method stems from velocity sedimentation studies of DNA populations, and from the simple methods of agarose gel electrophoresis. Our laboratories have developed quantitative agarose gel methods, analytical descriptions of DNA migration during electrophoresis on agarose gels (1-6), and electronic imaging for accurate determinations of DNA mass (7-9). Although all these components improve sensitivity and throughput of large numbers of samples (7,8,10), a simple version using only standard molecular biology equipment allows routine analysis of DNA damages at moderate frequencies. We present here a description of the methods, as well as a brief description of the underlying principles, required for a simplified approach to quantitation of DNA damages by alkaline gel electrophoresis.

  18. Gellan gum fluid gels for topical administration of diclofenac.

    Science.gov (United States)

    Mahdi, Mohammed H; Conway, Barbara R; Mills, Thomas; Smith, Alan M

    2016-12-30

    Diclofenac topical formulations are often preferred for drug administration to patients who experience serious GIT problems. Absorption of the drug through the skin, however, can be challenging due to the natural protective feature of the stratum corneum (SC). In this article, fluid gels prepared from gellan gum were explored as a topical drug delivery vehicle. Rheological analysis of the formulations showed that it was possible to produce a topical gel with a viscosity and the mechanical strength similar to that of the commercially available Voltaren ® gel using 1% w/w of a 50:50 low acyl/high acyl (LA/HA) gellan blend. Soft-tribology was used to assess the lubrication properties of gellan fluid gels. The lubrication of the gellan gum fluid gel formulations at high rubbing speeds was similar to the lubrication of the Voltaren ® gel. The use of gellan gum dramatically increased skin permeation of diclofenac when compared with the commercially available formulation and could be controlled by changing the gellan gum concentration and/or sodium ion concentration in the formulation. This study highlights the potential use of fluid gels that can be easily tuned to have physical properties suitable for topical formulations with the added advantage of increasing drug permeation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Western Blot of Stained Proteins from Dried Polyacrylamide Gels

    Science.gov (United States)

    Gruber, Claudia; Stan-Lotter, Helga

    1996-01-01

    Western blotting of proteins is customarily performed following their separation on polyacrylamide gels, either prior to staining (1) or, as recently reported, following staining (2). We describe here Western blotting with stained gels, which had been dried and some of which had been stored for years. This procedure permits immunological analysis of proteins, to which antisera may have become available only later, or where the application of newly developed sensitive detection methods is desired. Once rehydration of the gels is achieved, proteins can be-transferred to blotting membranes by any appropriate protocol. Proteins stained with Coomassie Blue have to be detected with a non-chromogenic method, such as the film-based enhanced chemiluminescence (ECL)2) procedure (3). Silver stained proteins, which transfer in the colorless form, may be visualized by any detection method, although, because of the usually very low amounts of proteins, detection by ECL is preferable. Blotting of stained proteins from rehydrated gels is as rapid and as quantitative as from freshly prepared gels, in contrast to blotting from wet stained gels, which requires extensive washing and results in low transfer efficiency (2). Together with a photographic record of the gel pattern, unambiguous identification of immunoreactive proteins from complex mixtures is possible. Some further applications of this work are discussed.

  20. Antimicrobial activity and the mechanism of silver nanoparticle thermosensitive gel

    Directory of Open Access Journals (Sweden)

    Chen M

    2011-11-01

    Full Text Available Meiwan Chen1,2,‡, Zhiwen Yang1,‡, Hongmei Wu1, Xin Pan1, Xiaobao Xie3, Chuanbin Wu11Research and Development Center of Pharmaceutical Engineering, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China; 2State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China; 3Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangzhou, China ‡These authors contributed equally to this workPurpose: The purpose of the present study was to elucidate the antimicrobial activity and mechanism of silver nanoparticles incorporated into thermosensitive gel (S-T-Gel on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.Patients and methods: This study investigated the growth, permeability, and morphology of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa cells in order to observe the action of S-T-Gel on the membrane structure of these three bacteria. The cell morphology of normal and treated bacteria cells was assessed by transmission electron microscopy (TEM, and the effects of S-T-Gel on genome DNA of bacterial cells were evaluated by agarose gel electrophoresis.Results: S-T-Gel showed promising activity against Staphylococcus aureus and moderate activity against Escherichia coli and Pseudomonas aeruginosa. The observation with TEM suggested that S-T-Gel may destroy the structure of bacterial cell membranes in order to enter the bacterial cell. S-T-Gel then condensed DNA and combined and coagulated with the cytoplasm of the damaged bacteria, resulting in the leakage of the cytoplasmic component and the eventual death of these three bacteria. In addition, the analysis of agarose gel electrophoresis demonstrated that S-T-Gel could increase the decomposability of genome DNA.Conclusion: These results about promising antimicrobial activity and mechanism of S-T-Gel may be useful for further research

  1. Organization versus frustration: low temperature transitions in a gelatine-based gel

    Energy Technology Data Exchange (ETDEWEB)

    Philipp, M; Mueller, U; Sanctuary, R; Baller, J; Krueger, J K [Laboratoire de Physique des Materiaux, Universite du Luxembourg, 162A, avenue de la Faiencerie, L-1511 (Luxembourg)], E-mail: martine.philipp@uni.lu

    2008-09-15

    A commercial physical gel composed of gelatine, water and glycerol shows a sol-gel transition which has been resolved by optical rotation measurements by step-wise heating the gel. This transition is not observable in the longitudinal acoustic mode measured at hypersonic frequencies with Brillouin spectroscopy. Depending on the thermal treatment of the investigated material during the sol-gel transition and within the gel state, Brillouin spectroscopy reflects tremendously different hypersonic dynamics. These distinct dynamics are responsible for the formation of different glassy states at low temperatures including that of a glass-ceramic. The large variety of super-cooled and glassy states is attributed to distinct distributions of the gel's constituents within the samples. Surprisingly, the same gel state can be produced either by annealing the gel over months or by the non-equilibrium effect of thermo-diffusion (Soret effect) in the course of some minutes.

  2. Self-Healing Corrosion Protective Sol-Gel Coatings

    NARCIS (Netherlands)

    Abdolah Zadeh, M.

    2016-01-01

    Inspired by the state of the art and the recent advances in the field of self-healing corrosion protective coatings, the thesis entitled “Self-healing corrosion protective sol-gel coatings” addresses novel routes to self-healing corrosion protective sol-gel coatings via extrinsic and intrinsic

  3. Sol-gel optical coatings for lasers: Part 1

    International Nuclear Information System (INIS)

    Floch, H.G.; Belleville, P.F.; Priotton, J.J.

    1995-01-01

    Many manufacturers and users claim that optical coatings are best prepared by physical vapor deposition technology. Others believe that sol-gel technology is an effective and competitive alternative. This article, the first of three, emphasizes sol-gel thin-film history and relates it to high-power laser technology, chemistry of the sol-gel process, production of optical coatings and deposition techniques. The second and third articles describe the preparation and performance of antireflective and highly reflective sol-gel optical coatings, respectively, that have been developed for the 1.8-MJ/500-TW (351-nm) pulsed neodymium-glass laser. This powerful laser is to be used in France's Inertial Confinement Fusion (ICF) program. It will demonstrate, at the laboratory scale, ignition of deuterium-tritium fusion fuel

  4. The role of quench rate in colloidal gels.

    Science.gov (United States)

    Royall, C Patrick; Malins, Alex

    2012-01-01

    Interactions between colloidal particles have hitherto usually been fixed by the suspension composition. Recent experimental developments now enable the control of interactions in situ. Here we use Brownian dynamics simulations to investigate the effect of controlling interactions upon gelation, by "quenching" the system from an equilibrium fluid to a gel. We find that, contrary to the normal case of an instantaneous quench, where the local structure of the gel is highly disordered, controlled quenching results in a gel with a much higher degree of local order. Under sufficiently slow quenching, local crystallisation is found, which is strongly enhanced when a monodisperse system is used. The higher the degree of local order, the smaller the mean squared displacement, indicating an enhancement of gel stability.

  5. Ageing of uranyl gel spherical particles

    International Nuclear Information System (INIS)

    Benadik, A.; Urbanek, V.; Vosecek, V.; Skvor, V.

    1978-01-01

    The structure and chemical composition of U(VI) gel are described and the course of crystal growth in ageing process at 22+-2 degC was found. Store conditions of probes had no influence on crystal growth rate. However, the way of probe storage influenced the quality and appearance of the xerogel obtained by drying via azeotropic distillation. The gel particles stored under trichloroethylene had a good appearance also after storing for 44 hours long. Particles stored in air saturated with H 2 O and NH 3 showed a worse appearance already after 20 hours. After 70 hours particles of spiny form were found. The worst particles were those stored under a trichloroethylene-ethylalcohol mixture. For storing purposes trichloroethylene was recommended as the most appropriate medium of gel protection. (author)

  6. Topical Colchicine Gel versus Diclofenac Sodium Gel for the Treatment of Actinic Keratoses: A Randomized, Double-Blind Study.

    Science.gov (United States)

    Faghihi, Gita; Elahipoor, Azam; Iraji, Fariba; Behfar, Shadi; Abtahi-Naeini, Bahareh

    2016-01-01

    Introduction. Actinic keratoses (AKs), a premalignant skin lesion, are a common lesion in fair skin. Although destructive treatment remains the gold standard for AKs, medical therapies may be preferable due to the comfort and reliability .This study aims to compare the effects of topical 1% colchicine gel and 3% diclofenac sodium gel in AKs. Materials and Methods. In this randomized double-blind study, 70 lesions were selected. Patients were randomized before receiving either 1% colchicine gel or 3% diclofenac sodium cream twice a day for 6 weeks. Patients were evaluated in terms of their lesion size, treatment complications, and recurrence at 7, 30, 60, and 120 days after treatment. Results. The mean of changes in the size was significant in both groups both before and after treatment ( 0.05). No case of erythema was seen in the colchicine group, while erythema was seen in 22.9% (eight cases) of patients in the diclofenac sodium group (p = 0.005). Conclusions. 1% colchicine gel was a safe and effective medication with fewer side effects and lack of recurrence of the lesion.

  7. Topical Colchicine Gel versus Diclofenac Sodium Gel for the Treatment of Actinic Keratoses: A Randomized, Double-Blind Study

    Directory of Open Access Journals (Sweden)

    Gita Faghihi

    2016-01-01

    Full Text Available Introduction. Actinic keratoses (AKs, a premalignant skin lesion, are a common lesion in fair skin. Although destructive treatment remains the gold standard for AKs, medical therapies may be preferable due to the comfort and reliability .This study aims to compare the effects of topical 1% colchicine gel and 3% diclofenac sodium gel in AKs. Materials and Methods. In this randomized double-blind study, 70 lesions were selected. Patients were randomized before receiving either 1% colchicine gel or 3% diclofenac sodium cream twice a day for 6 weeks. Patients were evaluated in terms of their lesion size, treatment complications, and recurrence at 7, 30, 60, and 120 days after treatment. Results. The mean of changes in the size was significant in both groups both before and after treatment ( 0.05. No case of erythema was seen in the colchicine group, while erythema was seen in 22.9% (eight cases of patients in the diclofenac sodium group (p = 0.005. Conclusions. 1% colchicine gel was a safe and effective medication with fewer side effects and lack of recurrence of the lesion.

  8. Screen-printable sol-gel enzyme-containing carbon inks.

    Science.gov (United States)

    Wang, J; Pamidi, P V; Park, D S

    1996-08-01

    Enzymes usually cannot withstand the high-temperature curing associated with the thick-film fabrication process and require a separate immobilization step in connection with the production of single-use biosensors. We report on the development of sol-gel-derived enzyme-containing carbon inks that display compatibility with the screen-printing process. Such coupling of sol-gel and thick-film technologies offers a one-step fabrication of disposable enzyme electrodes, as it obviates the need for thermal curing. The enzyme-containing sol-gel carbon ink, prepared by dispersing the biocatalyst, along with the graphite powder and a binder, within the sol-gel precursors, is cured very rapidly (10 min) at low temperature (4 °C). The influence of the ink preparation conditions is explored, and the sensor performance is evaluated in connection with the incorporation of glucose oxidase or horseradish peroxidase. The resulting strips are stable for at least 3 months. Such sol-gel-derived carbon inks should serve as hosts for other heat-sensitive biomaterials in connection with the microfabrication of various thick-film biosensors.

  9. Light scattering from a binary-liquid entanglement gel

    Science.gov (United States)

    Xia, K.-Q.; Maher, J. V.

    1987-09-01

    Light-scattering experiments have been carried out on an entanglement gel with a binary-liquid mixture as solvent. The onset temperature for critical opalescence has a composition dependence which is similar to the coexistence curve of the free-liquid mixture. This system resembles previously reported work on the cross-linked gel polyacrylamide in two ways: (1) As temperature is lowered toward the critical temperature of the free-liquid mixture, the binary-fluid gel exhibits a strong and increasing light scattering over a broad temperature region of several kelvins, and (2) no appreciable temporal fluctuations are observed throughout this temperature region. Two added features are observed in the present, entanglement-gel measurements: (a) Gel samples with solvent composition both near and off the critical composition of the free-liquid mixture exhibit similar light-scattering behavior, and (b) a Lorentzian-squared fit to the light-scattering angular distributions yields a characteristic wave number which does not change with temperature and an amplitude which shows a very strong dependence on the temperature.

  10. Cellulose gels produced in room temperature ionic liquids by ionizing radiation

    International Nuclear Information System (INIS)

    Kimura, Atsushi; Nagasawa, Naotsugu; Taguchi, Mitsumasa

    2014-01-01

    Cellulose-based gels were produced in room temperature ionic liquids (RTILs) by ionizing radiation. Cellulose was dissolved at the initial concentration of 20 wt% in 1-ethyl-3-methylimidazolium (EMI)-acetate or N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium (DEMA)-formate with a water content of 18 wt%, and irradiated with γ-rays under aerated condition to produce new cellulose gels. The gel fractions of the cellulose gels obtained in EMI-acetate and DEMA-formate at a dose of 10 kGy were 13% and 19%, respectively. The formation of gel fractions was found to depend on the initial concentration of cellulose, water content, and irradiation temperature. The obtained gel readily absorbed water, methanol, ethanol, dichloromethane, N,N-dimethylacetamide, and RTILs. - Highlights: • Cellulose gels were produced in room temperature ionic liquids (RTILs). • Water plays a crucial role in the cross-linking reaction. • Cellulose gels swollen with RTILs show good electronic conductivity (3.0 mS cm −1 )

  11. Spongy Gels by a Top-Down Approach from Polymer Fibrous Sponges.

    Science.gov (United States)

    Jiang, Shaohua; Duan, Gaigai; Kuhn, Ute; Mörl, Michaela; Altstädt, Volker; Yarin, Alexander L; Greiner, Andreas

    2017-03-13

    Ultralight cellular sponges offer a unique set of properties. We show here that solvent uptake by these sponges results in new gel-like materials, which we term spongy gels. The appearance of the spongy gels is very similar to classic organogels. Usually, organogels are formed by a bottom-up process. In contrast, the spongy gels are formed by a top-down approach that offers numerous advantages for the design of their properties, reproducibility, and stability. The sponges themselves represent the scaffold of a gel that could be filled with a solvent, and thereby form a mechanically stable gel-like material. The spongy gels are independent of a time-consuming or otherwise demanding in situ scaffold formation. As solvent evaporation from gels is a concern for various applications, we also studied solvent evaporation of wetting and non-wetting liquids dispersed in the sponge. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  12. А new factor effecting gel strength of pectin polysaccharides

    Directory of Open Access Journals (Sweden)

    S. E. Kholov

    2016-01-01

    Full Text Available Pectin polysaccharides obtained from various raw materials have a different component composition and form gels with water, sugar and acid or calcium. In this study, an experimental approach the gelation properties of different pectin samples, varied from different sources, using new methods of hydrolysis and purification. Samples were obtained by hydrolysis of accelerated extraction of pectin and purified by diaultrfiltration, have a high gel strength. The highest gel strength have been found in series of high methoxyl (HM- pectin samples of apple, peach, orange and low methoxyl (LM- pectin samples of commercial citrus pectin and apple pectin obtained by new method. It is shown that in addition to the basic parameters (the content of galacturonic acid, degree of esterification, molecular weight and hidrodinamic radius macromolecule to affect gel strength pectins aggregation of macromolecules, which is determined by the z-average molecular weight. There were observed a clear pattern of the influence of the molecular weight on hydrodynamic parameters for both HM- and LM- pectin samples on the gel strength. It were shown that a high values of molecular weight, intrinsic viscosity, and radius of gyration of pectin samples can significantly increase gel strength, while the value of Mz oppositely influenced the gel strength. As a result, a systematic analysis of this parameter and its relationship to the average molecular weight found that indeed the ratio Mz/Mw for pectin’s is an crucial to assess the quality of pectin at the study of gel strength for pectin polysaccharides.

  13. gel template method

    Indian Academy of Sciences (India)

    TiO2 nanotubes have been synthesized by sol–gel template method using alumina membrane. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, UV absorption spectrum and X-ray diffraction techniques have been used to investigate the structure, morphology and optical ...

  14. Improved gel electrophoresis matrix for hydrophobic protein separation and identification.

    Science.gov (United States)

    Tokarski, Caroline; Fillet, Marianne; Rolando, Christian

    2011-03-01

    We propose an improved acrylamide gel for the separation of hydrophobic proteins. The separation strategy is based on the incorporation of N-alkylated and N,N'-dialkylated acrylamide monomers in the gel composition in order to increase hydrophobic interactions between the gel matrix and the membrane proteins. Focusing on the most efficient monomer, N,N'-dimethylacrylamide, the potentiality of the new matrix was evaluated on membrane proteins of the human colon HCT-116 cell line. Protein analysis was performed using an adapted analytical strategy based on FT-ICR tandem mass spectrometry. As a result of this comparative study, including advanced reproducibility experiments, more hydrophobic proteins were identified in the new gel (average GRAVY: -0.085) than in the classical gel (average GRAVY: -0.411). Highly hydrophobic peptides were identified reaching a GRAVY value up to 1.450, therefore indicating their probable locations in the membrane. Focusing on predicted transmembrane domains, it can be pointed out that 27 proteins were identified in the hydrophobic gel containing up to 11 transmembrane domains; in the classical gel, only 5 proteins containing 1 transmembrane domain were successfully identified. For example, multiple ionic channels and receptors were characterized in the hydrophobic gel such as the sodium/potassium channel and the glutamate or the transferrin receptors whereas they are traditionally detected using specific enrichment techniques such as immunoprecipitation. In total, membrane proteins identified in the classical gel are well documented in the literature, while most of the membrane proteins only identified on the hydrophobic gel have rarely or never been described using a proteomic-based approach. 2010 Elsevier Inc. All rights reserved.

  15. User`s guide and documentation manual for ``PC-Gel`` simulator

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Ming-Ming; Gao, Hong W.

    1993-10-01

    PC-GEL is a three-dimensional, three-phase (oil, water, and gas) permeability modification simulator developed by incorporating an in-situ gelation model into a black oil simulator (BOAST) for personal computer application. The features included in the simulator are: transport of each chemical species of the polymer/crosslinker system in porous media, gelation reaction kinetics of the polymer with crosslinking agents, rheology of the polymer and gel, inaccessible pore volume to macromolecules, adsorption of chemical species on rock surfaces, retention of gel on the rock matrix, and permeability reduction caused by the adsorption of polymer and gel. The in-situ gelation model and simulator were validated against data reported in the literature. The simulator PC-GEL is useful for simulating and optimizing any combination of primary production, waterflooding, polymer flooding, and permeability modification treatments. A general background of permeability modification using crosslinked polymer gels is given in Section I and the governing equations, mechanisms, and numerical solutions of PC-GEL are given in Section II. Steps for preparing an input data file with reservoir and gel-chemical transport data, and recurrent data are described in Sections III and IV, respectively. Example data inputs are enclosed after explanations of each input line to help the user prepare data files. Major items of the output files are reviewed in Section V. Finally, three sample problems for running PC-GEL are described in Section VI, and input files and part of the output files of these problems are listed in the appendices. For the user`s reference a copy of the source code of PC-GEL computer program is attached in Appendix A.

  16. Behavior of water gel permissibles in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Ribovich, J.; Watson, R.W.

    1979-01-01

    This paper presents an overview of the successful use of water gel permissibles, since their introduction in 1970, with an emphasis on some problems of behavior in their field application. One is the metal clip or ties used to seal the water gel package. Miners are occasionally hit by the 2.4 mm metal wire expelled from boreholes in normal shooting operations. Manufacturers have consequently reduced the mass of the metal ties by 25-50%, providing a partial solution. Another problem concerned two reported instances of misfired water gel burning after coal shooting operations. Extensive tests have offered no satisfactory solution as yet, except to point up a principal shortcoming of water gels: that of pressure desensitization. Two other factors affecting sensitivity, and possibly resulting in misfires, are low temperature and aging. There is a decline in air-gap sensitivity with prolonged storage but all approved water gels seem capable of meeting requirements for long periods under normal storage conditions. Low temperature tests indicate the majority of water gels become insensitive to a No. 6 EBC at temperatures easily attained in cold weather storage. An attempt was made to determine the minimum temperature at which a nitroglycerin-sensitized permisslbe could be initiated with a No. 8 cap; a particularly granular one was initiated as low as minus 196 C. (5 refs.) (In English)

  17. Sol-gel synthesis of magnesium oxide-silicon dioxide glass compositions

    Science.gov (United States)

    Bansal, Narottam P.

    1988-01-01

    MgO-SiO2 glasses containing up to 15 mol pct MgO, which could not have been prepared by the conventional glass melting method due to the presence of stable liquid-liquid immiscibility, were synthesized by the sol-gel technique. Clear and transparent gels were obtained from the hydrolysis and polycondensation of silicon tetraethoxide (TEOS) and magnesium nitrate hexahydrate when the water/TEOS mole ratio was four or more. The gelling time decreased with increase in magnesium content, water/TEOS ratio, and reaction temperature. Magnesium nitrate hexahydrate crystallized out of the gels containing 15 and 20 mol pct MgO on slow drying. This problem was partially alleviated by drying the gels quickly at higher temperatures. Monolithic gel samples were prepared using glycerol as the drying control additive. The gels were subjected to various thermal treatments and characterized by several methods. No organic groups could be detected in the glasses after heat treatments to approx. 800 C, but trace amounts of hydroxyl groups were still present. No crystalline phase was found from X-ray diffraction in the gel samples to approx. 890 C. At higher temperatures, alpha quartz precipitated out as the crystalline phase in gels containing up to 10 mol pct MgO. The overall activation energy for gel formation in 10MgO-90SiO2 (mol pct) system for water/TEOS mole ratio of 7.5 was calculated to be 58.7 kJ/mol.

  18. Conducting Polymer Electrodes for Gel Electrophoresis

    OpenAIRE

    Bengtsson, Katarina; Nilsson, Sara; Robinson, Nathaniel D

    2014-01-01

    In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that p-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel ...

  19. Mass spectrometry compatible surfactant for optimized in-gel protein digestion.

    Science.gov (United States)

    Saveliev, Sergei V; Woodroofe, Carolyn C; Sabat, Grzegorz; Adams, Christopher M; Klaubert, Dieter; Wood, Keith; Urh, Marjeta

    2013-01-15

    Identification of proteins resolved by SDS-PAGE depends on robust in-gel protein digestion and efficient peptide extraction, requirements that are often difficult to achieve. A lengthy and laborious procedure is an additional challenge of protein identification in gel. We show here that with the use of the mass spectrometry compatible surfactant sodium 3-((1-(furan-2-yl)undecyloxy)carbonylamino)propane-1-sulfonate, the challenges of in-gel protein digestion are effectively addressed. Peptide quantitation based on stable isotope labeling showed that the surfactant induced 1.5-2 fold increase in peptide recovery. Consequently, protein sequence coverage was increased by 20-30%, on average, and the number of identified proteins saw a substantial boost. The surfactant also accelerated the digestion process. Maximal in-gel digestion was achieved in as little as one hour, depending on incubation temperature, and peptides were readily recovered from gel eliminating the need for postdigestion extraction. This study shows that the surfactant provides an efficient means of improving protein identification in gel and streamlining the in-gel digestion procedure requiring no extra handling steps or special equipment.

  20. A pneumatic device for rapid loading of DNA sequencing gels.

    Science.gov (United States)

    Panussis, D A; Cook, M W; Rifkin, L L; Snider, J E; Strong, J T; McGrane, R M; Wilson, R K; Mardis, E R

    1998-05-01

    This work describes the design and construction of a device that facilitates the loading of DNA samples onto polyacrylamide gels for detection in the Perkin Elmer/Applied Biosystems (PE/ABI) 373 and 377 DNA sequencing instruments. The device is mounted onto the existing gel cassettes and makes the process of loading high-density gels less cumbersome while the associated time and errors are reduced. The principle of operation includes the simultaneous transfer of the entire batch of samples, in which a spring-loaded air cylinder generates positive pressure and flexible silica capillaries transfer the samples. A retractable capillary array carrier allows the delivery ends of the capillaries to be held up clear of the gel during loader attachment on the gel plates, while enabling their insertion in the gel wells once the device is securely mounted. Gel-loading devices capable of simultaneously transferring 72 samples onto the PE/ABI 373 and 377 are currently being used in our production sequencing groups while a 96-sample transfer prototype undergoes testing.

  1. A simple gel electrophoresis method for separating polyhedral gold nanoparticles

    Science.gov (United States)

    Kim, Suhee; Lee, Hye Jin

    2015-07-01

    In this paper, a simple approach to separate differently shaped and sized polyhedral gold nanoparticles (NPs) within colloidal solutions via gel electrophoresis is described. Gel running parameters for separating efficiently gold NPs including gel composition, added surfactant types and applied voltage were investigated. The plasmonic properties and physical structure of the separated NPs extracted from the gel matrix were then investigated using transmission electron microscopy (TEM) and UV-vis spectrophotometry respectively. Data analysis revealed that gel electrophoresis conditions of a 1.5 % agarose gel with 0.1 % sodium dodecyl sulfate (SDS) surfactant under an applied voltage of 100 V resulted in the selective isolation of ~ 50 nm polyhedral shaped gold nanoparticles. Further efforts are underway to apply the method to purify biomolecule-conjugated polyhedral Au NPs that can be readily used for NP-enhanced biosensing platforms.

  2. Interaktion mellem warfarin og oral miconazol-gel

    DEFF Research Database (Denmark)

    Ogard, C G; Vestergaard, Henrik

    2000-01-01

    We report a case of a 76 year-old woman who had been taking warfarin for seven years because of relapsing deep venous thrombosis. Her daily maintenance dose was 5 mg. Monthly measurements of international normalised ratio (INR) were stable between 2-3. She developed oral candidiasis and miconazole...... gel was prescribed. One week later she developed bleeding gums. Eight days later she was admitted to the hospital with haematuria. INR was > 10. Warfarin and the miconazole gel were withdrawn. She was treated with phytonadione. INR normalised after four days and she continued warfarin treatment....... Caution should be exercised whenever the combination of warfarin and miconazole gel are prescribed....

  3. Silica gel matrix immobilized Chlorophyta hydrodictyon africanum ...

    African Journals Online (AJOL)

    Chlorophyta hydrodictyon africanum was immobilized on a silica gel matrix to improve its mechanical properties. The algae-silica gel adsorbent was used for batch sorption studies of a cationic dye, methylene blue (MB). Optimum adsorption was obtained with a dosage of 0.8 g bio sorbent. Results from sorption studies ...

  4. Gel Electrophoresis--The Easy Way for Students

    Science.gov (United States)

    VanRooy, Wilhelmina; Sultana, Khalida

    2010-01-01

    This article describes a simple, inexpensive, easy to conduct gel-electrophoresis activity using food dyes. It is an alternative to the more expensive counterparts which require agarose gel, DNA samples, purchased chamber and Tris-borate-EDTA buffer. We suggest some learning activities for senior biology students along with comments on several…

  5. Etodolac Containing Topical Niosomal Gel: Formulation Development and Evaluation

    Directory of Open Access Journals (Sweden)

    Gyati Shilakari Asthana

    2016-01-01

    Full Text Available The present study aimed to investigate the delivery potential of Etodolac (ETD containing topical niosomal gel. Niosomal formulations were prepared by thin film hydration method at various ratios of cholesterol and Span 60 and were evaluated with respect to particle size, shape, entrapment efficiency, and in vitro characteristics. Dicetyl phosphate (DCP was also added in the niosomal formulation. Mean particle size of niosomal formulation was found to be in the range of 2 μm to 4 μm. Niosomal formulation N2 (1 : 1 ratio of cholesterol and surfactant displayed good entrapment efficiency (96.72%. TEM analyses showed that niosomal formulation was spherical in shape. Niosomal formulation (N2 displayed high percentage of drug release after 24 h (94.91 at (1 : 1 ratio of cholesterol : surfactant. Further selected niosomal formulation was used to formulate topical gel and was characterized with respect to its various parameters such as pH, viscosity, spreadability, ex vivo study, and in vivo potential permeation. Ex vivo study showed that niosomal gel possessed better skin permeation study than the plain topical gel. Further in vivo study revealed good inhibition of inflammation in case of topical niosomal gel than plain gel and niosomal formulation. The present study suggested that topical niosomal gel formulations provide sustained and prolonged delivery of drug.

  6. Fibril formation from pea protein and subsequent gel formation.

    Science.gov (United States)

    Munialo, Claire Darizu; Martin, Anneke H; van der Linden, Erik; de Jongh, Harmen H J

    2014-03-19

    The objective of this study was to characterize fibrillar aggregates made using pea proteins, to assemble formed fibrils into protein-based gels, and to study the rheological behavior of these gels. Micrometer-long fibrillar aggregates were observed after pea protein solutions had been heated for 20 h at pH 2.0. Following heating of pea proteins, it was observed that all of the proteins were hydrolyzed into peptides and that 50% of these peptides were assembled into fibrils. Changes on a structural level in pea proteins were studied using circular dichroism, transmission electron microscopy, and particle size analysis. During the fibril assembly process, an increase in aggregate size was observed, which coincided with an increase in thioflavin T binding, indicating the presence of β-sheet aggregates. Fibrils made using pea proteins were more branched and curly. Gel formation of preformed fibrils was induced by slow acidification from pH 7.0 to a final pH of around pH 5.0. The ability of pea protein-based fibrillar gels to fracture during an amplitude sweep was comparable to those of soy protein and whey protein-based fibrillar gels, although gels prepared from fibrils made using pea protein and soy protein were weaker than those of whey protein. The findings show that fibrils can be prepared from pea protein, which can be incorporated into protein-based fibrillar gels.

  7. Screening of mucoadhesive vaginal gel formulations

    Directory of Open Access Journals (Sweden)

    Ana Ochoa Andrade

    2014-12-01

    Full Text Available Rational design of vaginal drug delivery formulations requires special attention to vehicle properties that optimize vaginal coating and retention. The aim of the present work was to perform a screening of mucoadhesive vaginal gels formulated with carbomer or carrageenan in binary combination with a second polymer (carbomer, guar or xanthan gum. The gels were characterised using in vitroadhesion, spreadability and leakage potential studies, as well as rheological measurements (stress and frequency sweep tests and the effect of dilution with simulated vaginal fluid (SVF on spreadability. Results were analysed using analysis of variance and multiple factor analysis. The combination of polymers enhanced adhesion of both primary gelling agents, carbomer and carrageenan. From the rheological point of view all formulations presented a similar behaviour, prevalently elastic and characterised by loss tangent values well below 1. No correlation between rheological and adhesion behaviour was found. Carbomer and carrageenan gels containing the highest percentage of xanthan gum displayed good in vitro mucoadhesion and spreadability, minimal leakage potential and high resistance to dilution. The positive results obtained with carrageenan-xanthan gum-based gels can encourage the use of natural biocompatible adjuvants in the composition of vaginal products, a formulation field that is currently under the synthetic domain.

  8. Large strain deformation behavior of polymeric gels in shear- and cavitation rheology

    Science.gov (United States)

    Hashemnejad, Seyed Meysam; Kundu, Santanu

    Polymeric gels are used in many applications including in biomedical and in food industries. Investigation of mechanical responses of swollen polymer gels and linking that to the polymer chain dynamics are of significant interest. Here, large strain deformation behavior of two different gel systems and with different network architecture will be presented. We consider biologically relevant polysaccharide hydrogels, formed through ionic and covalent crosslinking, and physically associating triblock copolymer gels in a midblock selective solvent. Gels with similar low-strain shear modulus display distinctly different non-linear rheological behavior in large strain shear deformation. Both these gels display strain-stiffening behavior in shear-deformation prior to macroscopic fracture of the network, however, only the alginate gels display negative normal stress. The cavitation rheology data show that the critical pressure for cavitation is higher for alginate gels than that observed for triblock gels. These distinctly different large-strain deformation behavior has been related to the gel network structure, as alginate chains are much stiffer than the triblock polymer chains.

  9. Numerical modelling and experimental study of liquid evaporation during gel formation

    Science.gov (United States)

    Pokusaev, B. G.; Khramtsov, D. P.

    2017-11-01

    Gels are promising materials in biotechnology and medicine as a medium for storing cells for bioprinting applications. Gel is a two-phase system consisting of solid medium and liquid phase. Understanding of a gel structure evolution and gel aging during liquid evaporation is a crucial step in developing new additive bioprinting technologies. A numerical and experimental study of liquid evaporation was performed. In experimental study an evaporation process of an agarose gel layer located on Petri dish was observed and mass difference was detected using electronic scales. Numerical model was based on a smoothed particle hydrodynamics method. Gel in a model was represented as a solid-liquid system and liquid evaporation was modelled due to capillary forces and heat transfer. Comparison of experimental data and numerical results demonstrated that model can adequately represent evaporation process in agarose gel.

  10. Biocatalysis with Sol-Gel Encapsulated Acid Phosphatase

    Science.gov (United States)

    Kulkarni, Suhasini; Tran, Vu; Ho, Maggie K.-M.; Phan, Chieu; Chin, Elizabeth; Wemmer, Zeke; Sommerhalter, Monika

    2010-01-01

    This experiment was performed in an upper-level undergraduate biochemistry laboratory course. Students learned how to immobilize an enzyme in a sol-gel matrix and how to perform and evaluate enzyme-activity measurements. The enzyme acid phosphatase (APase) from wheat germ was encapsulated in sol-gel beads that were prepared from the precursor…

  11. Synthesis of uranium and thorium dioxides by Complex Sol-Gel Processes (CSGP). Synthesis of uranium oxides by Complex Sol-Gel Processes (CSGP)

    International Nuclear Information System (INIS)

    Deptula, A.; Brykala, M.; Lada, W.; Olczak, T.; Wawszczak, D.; Chmielewski, A.G.; Modolo, G.; Daniels, H.

    2010-01-01

    In the Institute of Nuclear Chemistry and Technology (INCT), a new method of synthesis of uranium and thorium dioxides by original variant of sol-gel method - Complex Sol-Gel Process (CSGP), has been elaborated. The main modification step is the formation of nitrate-ascorbate sols from components alkalized by aqueous ammonia. Those sols were gelled into: - irregularly agglomerates by evaporation of water; - medium sized microspheres (diameter <150) by IChTJ variant of sol-gel processes by water extraction from drops of emulsion sols in 2-ethylhexanol-1 by this solvent. Uranium dioxide was obtained by a reduction of gels with hydrogen at temperatures >700 deg. C, while thorium dioxide by a simple calcination in the air atmosphere. (authors)

  12. Development of lidocaine gels for enhanced local anesthetic action.

    Science.gov (United States)

    Shin, Sang-Chul; Cho, Cheong-Weon; Yang, Kyu-Ho

    2004-12-09

    In relieving local pains, lidocaine, one of ester type local anesthetics, has been used. To develop the lidocaine gels of enhanced local anesthetic effects, hydroxypropyl methylcellulose (HPMC) based bioadhesive polymer gel containing an enhancer was formulated. As the drug concentration in the gels increased up to 3%, the permeation rate of drug linearly increased, thereafter reaching a plateau. As the temperature of surrounding solutions increased, the permeation of drug increased. The activation energy of drug permeation was 3.29 kcal/mol for lidocaine. The permeation rate of drug through skin was studied using various enhancers, such as glycols, non-ionic surfactants, and bile salts. Among the enhancers studied, diethylene glycol showed the greatest enhancing effects on drug permeation through skin. The analgesic activity was examined using a tail-flick analgesimeter. In the area under the efficacy curve (AUEC) of the rat-tail flick tests, lidocaine gel containing diethylene glycol showed about 3.89-fold increase in analgesic activity compared with the control. The addition of vasoconstrictor in the gels prolonged the analgesic effects. The result of this study supports that the bioadhesive gel with efficient anesthetic effect could be developed using HPMC with combination of enhancer and vasoconstrictor.

  13. Radiation hardening in sol-gel derived Er3+-doped silica glasses

    International Nuclear Information System (INIS)

    Hari Babu, B.; León Pichel, Mónica; Ollier, Nadège; El Hamzaoui, Hicham; Bigot, Laurent; Savelii, Inna; Bouazaoui, Mohamed; Poumellec, Bertrand; Lancry, Matthieu; Ibarra, Angel

    2015-01-01

    The aim of the present paper is to report the effect of radiation on the Er 3+ -doped sol-gel silica glasses. A possible application of these sol-gel glasses could be their use in harsh radiation environments. The sol-gel glasses are fabricated by densification of erbium salt-soaked nanoporous silica xerogels through polymeric sol-gel technique. The radiation-induced attenuation of Er 3+ -doped sol-gel silica is found to increase with erbium content. Electron paramagnetic resonance studies reveal the presence of E′ δ point defects. This happens in the sol-gel aluminum-silica glass after an exposure to γ-rays (kGy) and in sol-gel silica glass after an exposure to electrons (MGy). The concentration levels of these point defects are much lower in γ-ray irradiated sol-gel silica glasses. When the samples are co-doped with Al, the exposure to γ-ray radiation causes a possible reduction of the erbium valence from Er 3+ to Er 2+ ions. This process occurs in association with the formation of aluminum oxygen hole centers and different intrinsic point defects

  14. Hybrid sol-gel optical materials

    Science.gov (United States)

    Zeigler, John M.

    1992-01-01

    Hybrid sol-gel materials comprise silicate sols cross-linked with linear polysilane, polygermane, or poly(silane-germane). The sol-gel materials are useful as optical identifiers in tagging and verification applications and, in a different aspect, as stable, visible light transparent non-linear optical materials. Methyl or phenyl silicones, polyaryl sulfides, polyaryl ethers, and rubbery polysilanes may be used in addition to the linear polysilane. The linear polymers cross-link with the sol to form a matrix having high optical transparency, resistance to thermooxidative aging, adherence to a variety of substrates, brittleness, and a resistance to cracking during thermal cycling.

  15. Pelepasan Ibuprofen Dari Gel Karbomer 940 Kokristal Ibuprofen-Nikotinamida

    OpenAIRE

    Agustin, Rini; Sari, Novica; Zaini, Erizal

    2014-01-01

    Salah satu metode untuk meningkatkan kelarutan adalah co-kristalisasi. Ibuprofen dapat digunakan dalam aplikasi topikal untuk rheumatoid arthrisi, sehingga telah dilakukan sebuah studi tentang formulasi dan pelepasan kokristal ibuprofen-nikotinamida dari gel karbomer 940. Kokristal diperoleh dari metode penguapan pelarut dengan komposisi equimol (1:1). Gel terdiri dari dua formula dengan jumlah ibuprofen yang sama (5%). Formula pertama adalah gel kokristal ibuprofen-nicotinamida dan Formula d...

  16. Investigation on safety of gel decontamination technology

    International Nuclear Information System (INIS)

    Liu Zhihui; Song Fengli; Wang Yongxian; Zhang Taoge

    2014-01-01

    Gel decontamination technology is an advanced decontamination process of metal contaminated by radionuclide. It has the advantages such as simple operation process, high decontaminating factor, etc. But the disadvantages are that it has high spraying pressure and is strongly corrosive, which has safety risk to the operator and equipment. The effect of such factors as spraying pressure on operators was analyzed based on process feature, and it is proposed that it be worthwhile to make further study on the corrosion of gels to spraying equipment, taking into account corrosion feature of gels to stainless steel. Meanwhile, the safety issue was demonstrated on collecting and handling wastes from gel decontamination process. And then, protective measures, study methods, and solutions are put forward. The results show that protection should be strengthened during spraying to reduce the effect of splashing and fogging on workers; the equipment should be cleaned in time to reduce the effect of corrosion, and reducers should be added into waste liquid to eliminate the effect of residual detergent. (authors)

  17. Gel stabilization in chelate sol-gel preparation of Bi-2223 superconductors

    Czech Academy of Sciences Publication Activity Database

    Rubešová, K.; Jakeš, V.; Hlásek, T.; Vašek, Petr; Matějka, P.

    2012-01-01

    Roč. 73, č. 3 (2012), s. 448-453 ISSN 0022-3697 Institutional research plan: CEZ:AV0Z10100521 Keywords : superconductors * sol-gel growth * infrared spectroscopy * thermogravimetric analysis (TGA) * X-ray diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.527, year: 2012

  18. Comparative study of nano copper aluminate spinel prepared by sol–gel and modified sol–gel techniques: Structural, electrical, optical and catalytic studies

    International Nuclear Information System (INIS)

    Kumar, R. Thinesh; Suresh, P.; Selvam, N. Clament Sagaya; Kennedy, L. John; Vijaya, J. Judith

    2012-01-01

    Highlights: ► A modified sol–gel method for the preparation of nano CuAl 2 O 4 spinel using ethylenediamine was studied. ► Role of ethylenediamine in enhancing the structural, electrical, optical and catalytic properties of copper aluminate is highlighted. ► Effect of preparation method on the activity and selectivity of the samples on the oxidation of benzyl alcohol by CuAl 2 O 4 is studied. - Abstract: The effect of ethylenediamine addition in the sol–gel method for the preparation of nano CuAl 2 O 4 spinel for the enhancement in their structural, electrical, optical and catalytic properties was investigated. The samples were prepared by two different methods: sol–gel and modified sol–gel technique using ethylenediamine. X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), high resolution-transmission electron microscopy (HR-TEM), energy dispersive X-ray analysis (EDX), nitrogen adsorption/desorption isotherms, temperature dependent conductance measurements, thermoelectric power (TEP) measurements and UV–visible diffuse reflectance (UV–vis-DRS) spectra were used to characterize the samples prepared. CuAl 2 O 4 prepared by modified sol–gel technique was found to possess a higher surface area, lower crystallite size, lower activation energy and high porosity than the one prepared by sol–gel method which in turn lead to the improved performance of it towards the selective oxidation of benzyl alcohol to benzaldehyde. Effect of solvent on the catalytic oxidation of benzyl alcohol by the nano CuAl 2 O 4 prepared by modified sol–gel technique was also investigated.

  19. Spatially resolved speckle-correlometry of sol-gel transition

    Science.gov (United States)

    Isaeva, A. A.; Isaeva, E. A.; Pantyukov, A. V.; Zimnyakov, D. A.

    2018-04-01

    Sol-gel transition was studied using the speckle correlometry method with a localized light source and spatial filtering of backscattered radiation. Water solutions of technical or food gelatin with added TiO2 nanoparticles were used as studied objects. Structural transformation of "sol-gel" system was studied at various temperatures from 25°C to 50°C using analysis of the correlation and structure functions of speckle intensity fluctuations. The characteristic temperatures of "sol - gel" transition were evaluated for studied systems. Obtained results can be used for various applications in biomedicine and food industry.

  20. Sol-gel processing with inorganic metal salt precursors

    Science.gov (United States)

    Hu, Zhong-Cheng

    2004-10-19

    Methods for sol-gel processing that generally involve mixing together an inorganic metal salt, water, and a water miscible alcohol or other organic solvent, at room temperature with a macromolecular dispersant material, such as hydroxypropyl cellulose (HPC) added. The resulting homogenous solution is incubated at a desired temperature and time to result in a desired product. The methods enable production of high quality sols and gels at lower temperatures than standard methods. The methods enable production of nanosize sols from inorganic metal salts. The methods offer sol-gel processing from inorganic metal salts.

  1. Development of poloxamer gel formulations via hot-melt extrusion technology.

    Science.gov (United States)

    Mendonsa, Nicole S; Murthy, S Narasimha; Hashemnejad, Seyed Meysam; Kundu, Santanu; Zhang, Feng; Repka, Michael A

    2018-02-15

    Poloxamer gels are conventionally prepared by the "hot" or the "cold" process. But these techniques have some disadvantages such as high energy consumption, requires expensive equipment and often have scale up issues. Therefore, the objective of this work was to develop poloxamer gels by hot-melt extrusion technology. The model drug selected was ketoprofen. The formulations developed were 30% and 40% poloxamer gels. Of these formulations, the 30% poloxamer gels were selected as ideal gels. DSC and XRD studies showed an amorphous nature of the drug after extrusion. It was observed from the permeation studies that with increasing poloxamer concentration, a decrease in drug permeation was obtained. Other studies conducted for the formulations included in-vitro release studies, texture analysis, rheological studies and pH measurements. In conclusion, the hot-melt extrusion technology could be successfully employed to develop poloxamer gels by overcoming the drawbacks associated with the conventional techniques. Published by Elsevier B.V.

  2. Penetration effect of prostaglandin E2 gel on oral mucosa of rats

    Directory of Open Access Journals (Sweden)

    Rafinus Arifin

    2012-09-01

    Full Text Available Background: Several researches reported that Prostaglandin E2 (PGE2 injection on buccal mucosa combined with orthodontic pressure can faster tooth movement but has disadvantages such as high alveolar bone and root resorption furthermore pain from injection needle. PGE2 gel was made to better replace the lacks of injectable PGE2. Purpose: This research was aimed to prove that PGE 2 gel can penetrate rat’s oral mucosa effecting the appearance of PMN cells. Methods: This research was an in vivo laboratory experiment using 36 Sprague Dawley rats which were divided into 3 groups: normal group, topical PGE2 gel group after 1, 2, 4, 8 hours (4 subgroups, and topical gel without PGE2 group after 1, 2, 4, 8 hours (4 subgroups. Each group consists of 4 rats, therefore the total sample for all research groups were 36 rats. Gel with 25 µg/mL of PGE2 and gel without PGE2 were applied on oral mucosa for 2 minutes. Then, the rats were sacrificed after 1 hour, 2 hours, 4 hours, and 8 hours application. After that, the samples were prepared for histological examination with Hematoxyllin and Eosin. The picture were taken with OptiLab View and PMN cells amount were counted with light microscope, set 400 times of magnification. Results: Penetration effect of PGE2 gel on rat’s oral mucosa result in PMN inflammation cells distribution. One-way ANOVA showed no significant difference on PMN cells count in rats’ lower jaws between groups of normal and gel without PGE2. There was significant difference between groups of PGE2 gel and gel without PGE2 (p=0,001. PGE2 gel application showed PGE2 as inflammatory media, even though administered topically. Conclusion: PGE2 gel can penetrate rat’s oral mucosa, effecting PMN cells 1, 2, 4 and 8 hours after application of PGE2 gel.Latar belakang: Beberapa penelitian melaporkan bahwa injeksi (Prostaglandin E2 PGE2pada mukosa bukal yang dikombinasikan dengan tekanan ortodonti dapat mempercepat pergerakan gigi, tapi

  3. Clinical significance of measurement of changes in serum NO/NOS ratio and plasma ET content after treatment in patients with acute myocardial infarction (AMI)

    International Nuclear Information System (INIS)

    Dong Zhaoshu; Liu Xugui

    2005-01-01

    Objective: To study the clinical significance of changes of plasma ET and serum NO/NOS ratio in patients with AMI after treatment. Methods: Serum NO/NOS ratio (with EIA) and plasma ET (with RIA) contents were measured in 30 patients with acute myocardial infarction both before and after treatment as well as in 35 controls. Results: Serum levels of NO were significantly lower (P 0.05), but plasma ET levels remained significantly higher (P<0.05). Conclusion: Changes of serum NO/NOS ratio and plasma ET contents after treatment might be of prognostic importance in patients with acute myocardial infarction. (authors)

  4. Characterization of alkali silica reaction gels using Raman spectroscopy

    International Nuclear Information System (INIS)

    Balachandran, C.; Muñoz, J.F.; Arnold, T.

    2017-01-01

    The ability of Raman spectroscopy to characterize amorphous materials makes this technique ideal to study alkali silica reaction (ASR) gels. The structure of several synthetic ASR gels was thoroughly characterized using Raman Spectroscopy. The results were validated with additional techniques such as Fourier transmission infrared spectroscopy, X-ray powder diffraction and thermogravimetric analysis. The Raman spectra were found to have two broad bands in the 800 to 1200 cm −1 range and the 400 to 700 cm −1 range indicating the amorphous nature of the gel. Important information regarding the silicate polymerization was deduced from both of these spectral regions. An increase in alkali content of the gels caused a depolymerization in the silicate framework which manifested in the Raman spectra as a gradual shift of predominant peaks in both regions. The trends in silicate depolymerization were in agreement with results from a NMR spectroscopy study on similar synthetic ASR gels.

  5. Preparation of silica by sol-gel method using formamide

    Directory of Open Access Journals (Sweden)

    R.F.S. Lenza

    2001-07-01

    Full Text Available In this work we obtained microporous and mesoporous silica gels by sol-gel processing. Tetraethylortosilicate (TEOS was used as precursor. Nitric acid and hydrofluoric acid were used as catalysts. In order to study the affect of formamide as drying additive, we used a molar ratio alkoxide/formamide of 1/1. The performance of formamide in obtaining crack-free gels was evaluated through monolithicity measurements. The structural evolution occurring in the interconnected network of the gels during thermal treatment was monitored by Fourier transform infrared spectroscopy (FTIR, shrinkage and density measurements and nitrogen gas sorption. We noted that in the presence of formamide, the Si-O-Si bonds are stronger and belong to a more cross-linked structure. The samples obtained in the presence of formamide have larger pore volume and its pore structure is in the range of mesoporosity. The samples obtained without additive are microporous. Formamide allowed the preparation of crack-free silica gels stabilized at high temperatures.

  6. Sol-Gel Production; Proceedings of the First International Conference on Application and Commercialization of Sol-Gel Processing Held in Saarbruecken, Germany on 24-25 May 1993

    National Research Council Canada - National Science Library

    Schmidt, Helmut

    1998-01-01

    ...; Sol-Gel Coatings on Large Glass Substrates for Multilayer Interference Systems; A SiO2-ZrO2 Gel Film doped with Organic Pigments Made by the Sol-Gel Method for Contrast Enhancement of Color Picture Tubes...

  7. Anion embedded sol-gel films on Al for corrosion protection

    International Nuclear Information System (INIS)

    Sheffer, Mari; Groysman, Alec; Starosvetsky, David; Savchenko, Natali; Mandler, Daniel

    2004-01-01

    We report here on the successful incorporation of organic anions into a sol-gel film on Al as a means of enhancing the protection against corrosion. Following our previous study where we showed that hydrophobic sol-gel films provided pronounced corrosion inhibition, we studied the corrosion inhibition that phenylphosphonic acid (PPA) has when embedded inside a thin sol-gel coating on Al. The anion of this organic anion tends to stay inside a phenyltrimethoxysilane (PTMOS) based sol-gel film due to π-interactions. Our findings, which are derived primarily from potentiodynamic polarization measurements, electrochemical noise, scanning electron microscopy measurements and Auger electron spectroscopy (AES), clearly show that the organic phosphonate adds to the protection efficiency of the sol-gel film

  8. Abstracts of International Conference on Sol-Gel Materials' 04

    International Nuclear Information System (INIS)

    2004-01-01

    International Conference on Sol-Gel Materials '04 was an important forum for discussion on problems related to sol-gel processes applied for preparation materials with special physical properties and assignment. The application of sol-gel materials as phosphors, surface coatings, sensors, waveguides, medical implants, joints etc. has been presented. Preparation conditions, methods of physical characterization as well as optimal chemical composition of such materials have been also discussed in detail

  9. Formulation and evaluation of antipsoriatic gel using natural excipients

    OpenAIRE

    Raghupatruni Jhansi Laxmi; R. Karthikeyan; P. Srinivasa Babu; R.V.V. Narendra Babu

    2013-01-01

    Objective: To develop topical gel formulations of Psoralen using natural excipients to minimize the side effects of synthetic drugs. Methods: The Psoralen gel formulations were prepared using different natural gums and polymers. The physicochemical compatibility between Psoralen and other excipients was confirmed by using Fourier transform infrared spectroscopy. All prepared gel formulations were evaluated for drug content uniformity, viscosity, pH, and stability. The release of psoralen f...

  10. Anomalous piezoelectric properties of poly(vinylidene fluoride-trifluoroethylene)/ionic liquid gels

    Science.gov (United States)

    Fukagawa, Miki; Koshiba, Yasuko; Fukushima, Tatsuya; Morimoto, Masahiro; Ishida, Kenji

    2018-04-01

    Piezoelectric gels were prepared from low-volatile ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][TFSI]) gels, and their structural, ferroelectric, and piezoelectric properties were investigated. Poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE)/IL gels were formed using thermally reversible physical gels. The structural characterization indicated that the P(VDF-TrFE) molecules in the gels predominantly formed a ferroelectric phase (Form I) of P(VDF-TrFE). Polarization switching peaks were clearly observed using a three-layer stacked device structure. The coercive field of the P(VDF-TrFE)/IL gels substantially decreased to 4-9 MV/m, and their remnant polarizations were maintained at 63-71 mC/m2, which is similar to that for typical solid-state P(VDF-TrFE). Finally, the P(VDF-TrFE)/IL gel films exhibited a piezoelectric response, and the highest piezoelectric coefficient was ˜300 pm/V at an applied voltage frequency of 4 kHz.

  11. Structural and optical studies of nano-structure silica gel doped with different rare earth elements, prepared by two different sol -gel techniques

    International Nuclear Information System (INIS)

    Battisha, I.K.; El Beyally, A.; Seliman, S.I.; El Nahrawi, A.S.

    2005-01-01

    Structural and optical characteristics of pure silica gel (silica-xerogel, SiO 2 ) and doped with different concentrations ranging from 1 up to 6% of some rare earth (REEs) ions such as, praseodymium Pr +3 ,and Europium Eu +3 , Erbium Er +3 and Holmium Ho +3 , ions, in the form of thin film and monolith materials were prepared by sol - gel technique, Using tetra-ethoxysilane as precursor materials, which are of particular interest for sol-gel integrated optics applications. Some structural and optical features of sol-gel derived monolith and thin films are analyzed and compared, namely the structure of nano-particle monolith and thin film silica-gel samples, based on X-ray diffraction (XRD). The types of structural information obtainable are compared in detail. It is show that the XRD spectra of a-cristobalite are obtained for the two type materials and even by doping with the four REEs ions. Optical measurements of monolith and thin films were also studied and compared, the normal transmission and specular reflection were measured. The refractive index were calculated and discussed

  12. Characterization and Biocompatibility of Chitosan Gels with Silver and Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    C. Sámano-Valencia

    2014-01-01

    Full Text Available The presence of bacterial resistance to antibiotics is a very important issue and the search of new alternatives is necessary. In this work, a combination of chitosan gel with silver or gold nanoparticles was prepared and characterized using thermal, rheology, bactericide, and biocompatibility analyses. ESEM images were also taken to visualize the incorporation of the nanoparticles into the gel matrix. Thermal analysis showed a better thermal stability in the chitosan-gold nanoparticles gels compared to the chitosan-silver nanoparticles gels. Rheology analyses showed that the viscosity of the gels decreased when velocity increased and there were differences in viscosity when silver and gold nanoparticles concentrations change. ESEM images showed the presence of agglomerates of silver and gold nanoparticles into the gel matrix with a good distribution; in some cases the formation of microstructures was found. Bactericide results show that these materials present an antibacterial activity against S. aureus, S. mutans, and E. coli. The biocompatibility test showed neither negative reaction nor wound healing delay after the application of the gels in an in vivo test. The gels with silver and gold nanoparticles could be used to treat wound infections in oral or skin applications.

  13. Inter-crosslinking network gels having both shape memory and high ductility

    Science.gov (United States)

    Amano, Yoshitaka; Hidema, Ruri; Furukawa, Hidemitsu

    2012-04-01

    Medical treatment for injuries should be easy and quick in many accidents. Plasters or bandages are frequently used to wrap and fix injured parts. If plasters or bandages have additional smart functions, such as cooling, removability and repeatability, they will be much more useful and effective. Here we propose innovative biocompatible materials, that is, nontoxic high-strength shape-memory gels as novel smart medical materials. These smart gels were prepared from two monomers (DMAAm and SA), a polymer (HPC), and an inter-crosslinking agent (Karenz-MOI). In the synthesis of the gels, 1) a shape-memory copolymer network is made from the DMAAm and the SA, and 2) the copolymer and the HPC are crosslinked by the Karenz-MOI. Thus the crosslinking points are connected only between the different polymers. This is our original technique of developing a new network structure of gels, named Inter-Crosslinking Network (ICN). The ICN gels achieve high ductility, going up to 700% strain in tensile tests, while the ICN gels contain about 44% water. Moreover the SA has temperature dependence due to its crystallization properties; thus the ICN gels obtain shape memory properties and are named ICN-SMG. While the Young's modulus of the ICN-SMG is large below their crystallization temperature and the gels behave like plastic materials, the modulus becomes smaller above the temperature and the gels turn back to their original shape.

  14. Deformation and fracture behavior of simulated particle gels

    NARCIS (Netherlands)

    Rzepiela, A.A.

    2003-01-01

    In this PhD project rheological properties of model particle gels are investigated using Brownian Dynamics (BD) simulations. Particle gels are systems of colloidal particles that form weakly bonded percolating networks interpenetrated by a suspending fluid. They are characterized as

  15. Silica Sol-Gel Entrapment of the Enzyme Chloro peroxidase

    International Nuclear Information System (INIS)

    Le, T.; Chan, S.; Ebaid, B.; Sommerhalter, M.

    2015-01-01

    The enzyme chloro peroxidase (CPO) was immobilized in silica sol-gel beads prepared from tetramethoxysilane. The average pore diameter of the silica host structure (∼3 nm) was smaller than the globular CPO diameter (∼6 nm) and the enzyme remained entrapped after sol-gel maturation. The catalytic performance of the entrapped enzyme was assessed via the pyrogallol peroxidation reaction. Sol-gel beads loaded with 4 μg CPO per mL sol solution reached 9-12% relative activity compared to free CPO in solution. Enzyme kinetic analysis revealed a decrease in K_cat but no changes in K_M or K_I . Product release or enzyme damage might thus limit catalytic performance. Yet circular dichroism and visible absorption spectra of transparent CPO sol-gel sheets did not indicate enzyme damage. Activity decline due to methanol exposure was shown to be reversible in solution. To improve catalytic performance the sol-gel protocol was modified. The incorporation of 5, 20, or 40% methyltrimethoxysilane resulted in more brittle sol-gel beads but the catalytic performance increased to 14% relative to free CPO in solution. The use of more acidic casting buffers (ph 4.5 or 5.5 instead of 6.5) resulted in a more porous silica host reaching up to 18% relative activity

  16. Dynamic Scaling of Colloidal Gel Formation at Intermediate Concentrations.

    Science.gov (United States)

    Zhang, Qingteng; Bahadur, Divya; Dufresne, Eric M; Grybos, Pawel; Kmon, Piotr; Leheny, Robert L; Maj, Piotr; Narayanan, Suresh; Szczygiel, Robert; Ramakrishnan, Subramanian; Sandy, Alec

    2017-10-27

    We have examined the formation and dissolution of gels composed of intermediate volume-fraction nanoparticles with temperature-dependent short-range attractions using small-angle x-ray scattering, x-ray photon correlation spectroscopy, and rheology to obtain nanoscale and macroscale sensitivity to structure and dynamics. Gel formation after temperature quenches to the vicinity of the rheologically determined gel temperature, T_{gel}, was characterized via the slowdown of dynamics and changes in microstructure observed in the intensity autocorrelation functions and structure factor, respectively, as a function of quench depth (ΔT=T_{quench}-T_{gel}), wave vector, and formation time t_{f}. We find the wave-vector-dependent dynamics, microstructure, and rheology at a particular ΔT and t_{f} map to those at other ΔTs and t_{f}s via an effective scaling temperature, T_{s}. A single T_{s} applies to a broad range of ΔT and t_{f} but does depend on the particle size. The rate of formation implied by the scaling is a far stronger function of ΔT than expected from the attraction strength between colloids. We interpret this strong temperature dependence in terms of cooperative bonding required to form stable gels via energetically favored, local structures.

  17. High lane density slab-gel electrophoresis using micromachined instrumentation.

    Science.gov (United States)

    Papautsky, I; Mohanty, S; Weiss, R; Frazier, A B

    2001-10-01

    In this paper, micromachined pipette arrays (MPAs) and microcombs were studied as a means of enabling high lane density gel electrophoresis. The MPA provide a miniaturized format to interface sub-microliter volumes of samples between macroscale sample preparation formats and microscale biochemical analysis systems. The microcombs provide a means of creating sample loading wells in the gel material on the same center-to-center spacing as the MPAs. Together, the two micromachined instruments provide an alternative to current combs and pipetting technologies used for creating sample loading wells and sample delivery in gel electrophoresis systems. Using three designs for the microcomb-MPA pair, center-to-center spacings of 1.0 mm, 500 microm, and 250 microm are studied. The results demonstrate an approximate 10-fold increase in lane density and a 10-fold reduction in sample size from 5 microL to 500 pL. As a result, the number of theoretical plates has increased 2.5-fold, while system resolution has increased 1.5-fold over the conventional agarose gel systems. An examination of changes in resolution across the width of individual separation lanes in both systems revealed dependence in the case of the conventional gels and no dependence for the gels loaded with the micromachined instrumentation.

  18. Unexpected Inflammatory Effects of Intravaginal Gels (Universal Placebo Gel and Nonoxynol-9 on the Upper Female Reproductive Tract: A Randomized Crossover Study.

    Directory of Open Access Journals (Sweden)

    Karen Smith-McCune

    Full Text Available Intravaginal anti-HIV microbicides could provide women with a self-controlled means for HIV prevention, but results from clinical trials have been largely disappointing. We postulated that unrecognized effects of intravaginal gels on the upper female reproductive tract might contribute to the lower-than-expected efficacy of HIV microbicides. Our objective was to study the effects of intravaginal gels on the immune microenvironment of the cervix and uterus. In this randomized crossover study, 27 healthy female volunteers used a nightly application of intravaginal nonoxynol-9 (N9 gel as a "failed" microbicide or the universal placebo gel (UPG as a "safe" gel (intervention cycles, or nothing (control cycle from the end of menses to the mid-luteal phase. At a specific time-point following ovulation, all participants underwent sample collection for measurements of T-cell phenotypes, gene expression, and cytokine/chemokine protein concentrations from 3 anatomic sites above the vagina: the cervical transformation zone, the endocervix and the endometrium. We used hierarchical statistical models to estimate mean (95% CI intervention effects, for N9 and UPG relative to control. Exposure to N9 gel and UPG generated a common "harm signal" that included transcriptional up-regulation of inflammatory genes chemokine (C-C motif ligand 20 (macrophage inflammatory factor-3alpha and interleukin 8 in the cervix, decreased protein concentrations of secretory leukocyte protease inhibitor, and transcriptional up-regulation of inflammatory mediators glycodelin-A and osteopontin in the endometrium. These results need to be replicated with a larger sample, but underscore the need to consider the effects of microbicide agents and gel excipients on the upper female reproductive tract in studies of vaginal microbicides.

  19. Solution-mediated growth of NBA-ZSM-5 crystals retarded by gel entrapment

    Science.gov (United States)

    Aguilar-Mamani, Wilson; Akhtar, Farid; Hedlund, Jonas; Mouzon, Johanne

    2018-04-01

    The synthesis of flat tablet-shaped ZSM-5 crystals from a gel using metakaolin as aluminosilicate source and n-butyl amine as structure directing agent was investigated. The evolution inside the solid phase was characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, thermogravimetry and mass spectrometry. A kinetic study indicated that the nucleation of the majority crystals occurred concurrently with the formation of the gel upon heating the starting liquid suspension. Microstructural evidences undeniably showed that the gel precipitated on ZSM-5 crystals and mineral impurities originating from kaolin. As a result, crystal growth was retarded by gel entrapment, as indicated by the configuration and morphology of the embedded crystals. The results presented herein are harmonized with a solution-mediated nucleation and growth mechanism. Our observations differ from the autocatalytic model that suggests that the nuclei rest inside the gel until released when the gel is consumed. Our results show instead that it is crystals that formed in an early stage before entrapment inside the gel that rest inside the gel until exposed at the gel surface. These results illustrate the limitation of the classical method used in the field to determine nucleation profiles when the crystals become trapped inside the gel.

  20. In Situ Formation of Steroidal Supramolecular Gels Designed for Drug Release

    Directory of Open Access Journals (Sweden)

    Hana Bunzen

    2013-03-01

    Full Text Available In this work, a steroidal gelator containing an imine bond was synthesized, and its gelation behavior as well as a sensitivity of its gels towards acids was investigated. It was shown that the gels were acid-responsive, and that the gelator molecules could be prepared either by a conventional synthesis or directly in situ during the gel forming process. The gels prepared by both methods were studied and it was found that they had very similar macro- and microscopic properties. Furthermore, the possibility to use the gels as carriers for aromatic drugs such as 5-chloro-8-hydroxyquinoline, pyrazinecarboxamide, and antipyrine was investigated and the prepared two-component gels were studied with regard to their potential applications in drug delivery, particularly in a pH-controlled drug release.

  1. Applications and Properties of Ionic Liquid- Based Gels and Soft Solid Composites

    Science.gov (United States)

    Voss, Bret Alan McGinness

    2011-12-01

    Solid-liquid composites (gels) have a combination of properties that afford new material applications in which high solute diffusion is desirable. These composites have a soft-solid mechanical integrity and will not flow under gravity, but entrain a liquid matrix (i.e. 60-98 mass %) which allows for high diffusion and high reactivity. Room temperature ionic liquid (RTILs) are molten organic salts with a melting point below room temperature and negligible vapor pressure. If the RTILs are used as the liquid component of a gel, then the gel matrix will not evaporate (unlike other organic solvents) and may be used for long term applications. This thesis research applies RTIL gels for two new applications; carbon dioxide/nitrogen separation and chemical warfare agent (CWA) barrier and decontamination. Separating CO2 from the flue gas of coal and gas fired power-plants is an increasingly economically and environmentally important gas separation. In this first study, RTIL gels are cast in a supported membrane and gas permeability and ideal selectivity are measured. The RTIL matrix has an inherent affinity for CO2 and provides a high diffusion, hence high permeability (i.e. 500-700 barrer). The solidifying component is a low molecular-weight organic gelator (LMOG) which through physical bonding interactions (i.e. hydrogen bonding, pi-pi stacking and van der Walls forces) forms an entangled network which provides mechanical stability (i.e. increase trans-membrane pressure required to expel selective material from the support). In these studies two LMOGs and five RTILs are used to make supported gel membranes and determine gas permeability and temperature dependent trends. The second application for RTIL gels is a decontaminating barrier for CWAs and toxic industrial compounds (TICs). In these studies a layer of RTIL gel is applied on top of a substrate contaminated with a CWA simulant (i.e. chloroethylethylsulfide, CEES). The gel performs well as a barrier, preventing CEES

  2. Capillary gel electrophoresis for rapid, high resolution DNA sequencing.

    OpenAIRE

    Swerdlow, H; Gesteland, R

    1990-01-01

    Capillary gel electrophoresis has been demonstrated for the separation and detection of DNA sequencing samples. Enzymatic dideoxy nucleotide chain termination was employed, using fluorescently tagged oligonucleotide primers and laser based on-column detection (limit of detection is 6,000 molecules per peak). Capillary gel separations were shown to be three times faster, with better resolution (2.4 x), and higher separation efficiency (5.4 x) than a conventional automated slab gel DNA sequenci...

  3. Effects of Shear Fracture on In-depth Profile Modification of Weak Gels

    Institute of Scientific and Technical Information of China (English)

    Li Xianjie; Song Xinwang; Yue Xiang'an; Hou Jirui; Fang Lichun; Zhang Huazhen

    2007-01-01

    Two sand packs were filled with fine glass beads and quartz sand respectively. The characteristics of crosslinked polymer flowing through the sand packs as well as the influence of shear fracture of porous media on the in-depth profile modification of the weak gel generated from the crosslinked polymer were investigated. The results indicated that under the dynamic condition crosslinking reaction happened in both sand packs,and the weak gels in these two cases became small gel particles after water flooding. The differences were:the dynamic gelation time in the quartz sand pack was longer than that in the glass bead pack. Residual resistance factor (FRR) caused by the weak gel in the quartz sand pack was smaller than that in the glass bead pack. The weak gel became gel particles after being scoured by subsequent flood water. A weak gel with uniform apparent viscosity and sealing characteristics was generated in every part of the glass bead pack,which could not only move deeply into the sand pack but also seal the high capacity channels again when it reached the deep part. The weak gel performed in-depth profile modification in the glass bead pack,while in the quartz sand pack,the weak gel was concentrated with 100 cm from the entrance of the sand pack. When propelled by the subsequent flood water,the weak gel could move towards the deep part of the sand pack but then became tiny gel particles and could not effectively seal the high capacity channels there. The in-depth profile modification of the weak gel was very weak in the quartz sand pack. It was the shear fracture of porous media that mainly affected the properties and weakened the in-depth profile modification of the weak gel.

  4. Structural Evolution and Stability of Sol-Gel Biocatalysts

    International Nuclear Information System (INIS)

    Rodgers, L.E.; Foster, L.J.R.; Holden, P.J.; Knott, R.B.; Bartlett, J.B.

    2005-01-01

    Full text: Immobilisation strategies for catalytic enzymes are important as they allow reuse of the biocatalysts. Sol-gel materials have been used to immobilise Candida antarctica lipase B (CALB), a commonly used industrial enzyme with a known crystal structure. The sol-gel bioencapsulate is produced through the condensation of suitable metal alkoxides in the presence of CALB, yielding materials with controlled pore sizes, volume and surface chemistry. Sol-gel matrices have been shown to prolong the catalytic life and enhance the activity of CALB, although the molecular basis for this effect has yet to be elucidated due to the limitations of analysis techniques applied to date. Small angle neutron scattering (SANS) allows such multicomponent systems to be characterised through contrast matching. In the sol-gel bioencapsulate system, at the contrast match point for silica, residual scattering intensity is due to the CALB and density fluctuations in the matrix. A SANS contrast variation series found the match point for the silica matrix, both with and without enzyme present, to be around 35 percent. The model presented here proposes a mechanism for the interaction between CALB and the surrounding sol-gel matrix, and the observed improvement in enzyme activity and matrix strength. The SANS protocol developed here may be applied more generally to bioencapsulates. (authors)

  5. Reproducibility and signal response linearity of Alanine gel dosimeter

    International Nuclear Information System (INIS)

    Silva, Cleber Feijo Silva; Campos, Leticia Lucente

    2008-01-01

    Gel Dosimetry has been studied mainly for medical applications, because it presents signal response in the dose range used in radiotherapy treatments and it can be applied for three dimensional dosimetry. Alanine gel dosimeter is a new gel material developed at IPEN that presents significant improvement on previous alanine systems developed by Costa (1994). The DL-Alanine (C 3 H 7 NO 2 ) is an amino acid tissue equivalent that improves the production of ferric ions in the solution. These ferric ions concentration can be measured by spectrophotometry technique. This work aims to study the reproducibility of the alanine gel solutions and the signal response as a function of gamma radiation dose, considering that these two properties are very important for characterizing and standardizing any dosimeter. (author)

  6. Optimization and evaluation of thermoresponsive diclofenac sodium ophthalmic in situ gels.

    Science.gov (United States)

    Asasutjarit, Rathapon; Thanasanchokpibull, Suthira; Fuongfuchat, Asira; Veeranondha, Sukitaya

    2011-06-15

    This work was conducted to optimize and evaluate Pluronic F127-based thermoresponsive diclofenac sodium ophthalmic in situ gels (DS in situ gel). They were prepared by cold method and investigated their physicochemical properties i.e., pH, flow ability, sol-gel transition temperature, gelling capacity and rheological properties. An optimized formulation was selected and investigated its physicochemical properties before and after autoclaving, eye irritation potency in SIRC cells and rabbits. In vivo ophthalmic absorption was performed in rabbits. It was found that physicochemical properties of DS in situ gels were affected by formulation compositions. Increment of Pluronic F127 content decreased sol-gel transition temperature of the products while increase in Pluronic F68 concentration tended to increase sol-gel transition temperature. In this study, Carbopol 940 did not affect sol-gel transition temperature but it affected transparency, pH, and gelling capacity of the products. The optimized formulation exhibited sol-gel transition at 32.6 ± 1.1 °C with pseudoplastic flow behavior. It was lost diclofenac sodium content during autoclaving. However, it was accepted as safe for ophthalmic use and could increase diclofenac sodium bioavailability in aqueous humor significantly. In conclusion, the optimized DS in situ gel had potential for using as an alternative to the conventional diclofenac sodium eye drop. However, autoclaving was not a suitable sterilization method for this product. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Antiinflammatory effects of Viola tricolor gel in a model of sunburn in rats and the gel stability study.

    Science.gov (United States)

    Piana, Mariana; Silva, Mariane Arnoldi; Trevisan, Gabriela; de Brum, Thiele Faccim; Silva, Cássia Regina; Boligon, Aline Augusti; Oliveira, Sara Marchesan; Zadra, Marina; Hoffmeister, Carin; Rossato, Mateus Fortes; Tonello, Raquel; Laporta, Luciane Varini; de Freitas, Robson Borba; Belke, Bianca Vargas; Jesus, Roberta da Silva; Ferreira, Juliano; Athayde, Margareth Linde

    2013-11-25

    Viola tricolor, popularly known as heartsease has been empirically used in several skin disorders, including burns. The objective of this study was investigate the antinociceptive and antiinflammatory effect of a gel containing extract of Viola tricolor flowers on thermal burn induced by UVB irradiation and to perform gel stability study. The antinociceptive and antiinflammatory effect were evaluated by static and dynamic mechanical allodynia model, paw edema, and neutrophilic cell infiltration. Metabolites compounds were quantified by HPLC. The gel stability study was performed analyzing organoleptical aspects, besides pH, viscosity, and quantification of rutin by HPLC. In the results were evidenced changes in threshold in statical and dynamic mechanical allodynia (I(max)=100 ± 10% and 49 ± 10%, respectively), paw edema (I(max)=61 ± 6%), and myeloperoxidase activity (I(max)=89 ± 5%). Such effects may be attributed, in part, to rutin, salicylic and chlorogenic acids, and others compounds found in this species. No important changes were detected in the stability study, in all aspects analyzed in temperature below 25 °C. These findings suggest that Viola tricolor gel has an antinociceptive and antiinflammatory effect in the ultraviolet-B-induced burn, since maintain the temperature below 25 °C. © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Radiation reaction of skin treatment with nucliderm-gel

    International Nuclear Information System (INIS)

    Pandova, V.; Marinova, Ts.; Stefanova, D.; Pantev, T.; Yankova, S.

    1988-01-01

    The process of epithelization and the anticeptic effect of nucliderm-gel applied locally have been studied in 63 oncological patients subjected to radiotherapy. In all cases under study nucliderm-gel promotes skin epithelization and has a high antiseptic effect as compared with the drugs applied hitherto

  9. Silica- and germania-based dual-ligand sol-gel organic-inorganic hybrid sorbents combining superhydrophobicity and π-π interaction. The role of inorganic substrate in sol-gel capillary microextraction.

    Science.gov (United States)

    Seyyal, Emre; Malik, Abdul

    2017-04-29

    Principles of sol-gel chemistry were utilized to create silica- and germania-based dual-ligand surface-bonded sol-gel coatings providing enhanced performance in capillary microextraction (CME) through a combination of ligand superhydrophobicity and π-π interaction. These organic-inorganic hybrid coatings were prepared using sol-gel precursors with bonded perfluorododecyl (PF-C 12 ) and phenethyl (PhE) ligands. Here, the ability of the PF-C 12 ligand to provide enhanced hydrophobic interaction was advantageously combined with π-π interaction capability of the PhE moiety to attain the desired sorbent performance in CME. The effect of the inorganic sorbent component on microextraction performance of was explored by comparing microextraction characteristics of silica- and germania-based sol-gel sorbents. The germania-based dual-ligand sol-gel sorbent demonstrated superior CME performance compared to its silica-based counterpart. Thermogravimetric analysis (TGA) of the created silica- and germania-based dual-ligand sol-gel sorbents suggested higher carbon loading on the germania-based sorbent. This might be indicative of more effective condensation of the organic ligand-bearing sol-gel-active chemical species to the germania-based sol-gel network (than to its silica-based counterpart) evolving in the sol solution. The type and concentration of the organic ligands were varied in the sol-gel sorbents to fine-tune extraction selectivity toward different classes of analytes. Specific extraction (SE) values were used for an objective comparison of the prepared sol-gel CME sorbents. The sorbents with higher content of PF-C 12 showed remarkable affinity for aliphatic hydrocarbons. Compared to their single-ligand sol-gel counterparts, the dual-ligand sol-gel coatings demonstrated significantly superior CME performance in the extraction of alkylbenzenes, providing up to ∼65.0% higher SE values. The prepared sol-gel CME coatings provided low ng L -1 limit of detections (LOD

  10. Development of hydroxyapatite-chitosan gel sunscreen combating clinical multidrug-resistant bacteria

    Science.gov (United States)

    Morsy, Reda; Ali, Sameh S.; El-Shetehy, Mohamed

    2017-09-01

    The several harmful effects on infected human skin resulting from exposure to the sun's UV radiation generate an interest in the development of a multifunctional hydroxyapatite-chitosan (HAp-chitosan) gel that works as an antibacterial sunscreen agent for skin care. In this work, HAp-chitosan gel was synthesized via coprecipitation method by dissolving chitosan in phosphoric acid and adding HAp. The characteristics of HAp-chitosan composite were investigated by conventional techniques, such as XRD, FTIR, and SEM techniques, while its sunscreen property was investigated by UV-spectroscopy. In addition to the influence of the gel on bacterial cell morphology, the antibacterial activity of HAp-chitosan gel against clinical multidrug resistant skin pathogens, such as Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa has been studied. The results revealed the formation of HAp-chitosan gel having nanosized particles, which confers protection against UV-radiation. The antibacterial activity records showed that chitosan-HAp gel exhibits a significant effect on the growth and ultrastructure of multi-drug resistant bacterial activities. Therefore, the chitosan-HAp gel is promising for skin health care as an antibacterial sunscreen.

  11. Formulation and method for preparing gels comprising hydrous aluminum oxide

    Science.gov (United States)

    Collins, Jack L.

    2014-06-17

    Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

  12. Reduction of Driver Stress Using AmI Technology while Driving in Motorway Merging Sections

    Science.gov (United States)

    Zia, Kashif; Riener, Andreas; Ferscha, Alois

    High average intensity of traffic and problems like traffic congestions, road safety, etc. are challenging problems striking highway operators in these days. With the broad application of intelligent transport systems (ITS), particularly for the most dense street sections, some of these problems can be minimized or even solved; supplementary great potential is attributed to applications based on state-of-the art technology like car-to-x communication, for instance by extending an individuals "field of vision" by observations taken from all the vehicles in front. In this work we present a simulation based approach for improving driving experience and increasing road safety in merging sections by redirecting vehicles in advance according to a negotiation of requirements and desires of the flowing traffic on the main road and cars merging from the entrance lane. The simulation experiments performed in a cellular automaton based environment were data driven and on real scale, using traffic flow data on a minute-by-minute basis from a large urban motorway in a main city of the European Union. Our results have shown that the application of AmI technology has potential to influence driver's behavior (seamlessly invoking for a lane change well before an abrupt merging point) resulting in a reduction of panic, particularly for sections with limited range of view.

  13. Dehydration and crystallization kinetics of zirconia-yttria gels

    International Nuclear Information System (INIS)

    Ramanathan, S.; Muraleedharan, R.V.; Roy, S.K.; Nayar, P.K.K.

    1995-01-01

    Zirconia and zirconia-yttria gels containing 4 and 8 mol% yttria were obtained by coprecipitation and drying at 373 K. The dehydration and crystallization behavior of the dried gels was studied by DSC, TG, and XRD. The gels undergo elimination of water over a wide temperature range of 373--673 K. The peak temperature of the endotherm corresponding to dehydration and the kinetic constants for the process were not influenced by the yttria content of the gel. The enthalpy of dehydration observed was in good agreement with the heat of vaporization data. The dehydration was followed by a sharp exothermic crystallization process. The peak temperature of the exotherm and the activation energy of the process increased with an increase in yttria content, while the enthalpy of crystallization showed a decrease. The ''glow effect'' reduced with increasing yttria content. Pure zirconia crystallizes in the tetragonal form while the zirconia containing 4 and 8 mol% yttria appears to crystallize in the cubic form

  14. New decontamination techniques: chemical gels, electropolishing and abrasives

    International Nuclear Information System (INIS)

    Brunel, G.; Gauchon, J.P.; Kervegant, Y.; Josso, F.

    1991-01-01

    The decommissioning of nuclear installations requires decontamination techniques that are efficient, simple to apply and producing a small amount of wastes, which are easy to process. With a view to this, three decontamination methods, which appear to be particularly suited to decommissioning, have been studied. These three methods are: - spraying of gels carrying chemical decontaminating agents, - electropolishing with a swab device, - abrasives blasting. After parametric tests on non-radioactive and active samples, the industrial application of these methods in the dismantling of installations was studied. These industrial applications concern: - decontamination of pieces coming from the German BWR ISAR by immersion and gel spraying, - decontamination, mainly by gel spraying, and dismantling of the BRENNILIS bituminisation plant, - decontamination of part of the cooling circuit of the graphite gas reactor G2 by gel spraying, - decontamination of a component of the FBR SuperPhenix, using dry abrasives blasting. During the first three applications, generated secondary wastes volume and form were determined. 33 tabs., 16 figs., 12 refs

  15. Influence of remineralizing gels on bleached enamel microhardness in different time intervals.

    Science.gov (United States)

    Borges, Alessandra Bühler; Yui, Karen Cristina Kazue; D'Avila, Thaís Corrêa; Takahashi, Camila Lurie; Torres, Carlos Rocha Gomes; Borges, Alexandre Luis Souto

    2010-01-01

    This study evaluated the influence of bleaching gel pH, the effect of applying remineralizing gels after bleaching and the effect of artificial saliva on enamel microhardness. Seventy bovine incisors were divided into three groups: Group 1 (n=10) received no bleaching procedure (control); Group 2 was bleached with a 35% hydrogen peroxide neutral gel (n=30) and Group 3 was bleached with a 35% hydrogen peroxide acid gel (n=30). Each experimental group was subdivided into three groups (n=10) according to the post-bleaching treatment: storage in artificial saliva, application of a fluoride gel and application of a combination of calcium and fluoride gel. The specimens were stored in artificial saliva for 7, 15 and 30 days and enamel microhardness was evaluated. The Vickers microhardness data were analyzed by three-way RM ANOVA, which revealed a significant difference only for treatment factor. The Tukey's test showed that the groups bleached followed by no additional treatment exhibited microhardness means significantly lower than the bleached groups treated with remineralizing gels. The Dunnet's test showed a significant difference only for the group bleached with acid gel without remineralizing treatment compared to the control group measured immediately after bleaching. It was concluded that acid bleaching gel significantly reduced enamel microhardness and that use of remineralizing gels after bleaching can significantly enhance the microhardness of bleached enamel.

  16. Oxytetracycline removal from water by novel microbial embedding gel beads

    Science.gov (United States)

    Wu, Nan; Pan, Peng; Zeng, Ming; Wang, Wei; Xu, Chenshan; Zhang, Zongpeng; Liu, Xinyuan; Wang, Yichao

    2018-01-01

    As a common antibiotic in aquatic environment, excessive oxytetracycline (OTC) is urgent to be removed due to its great biological toxicity. Compared with the traditional activated sludge, microbial embedding can enhance the treating efficiency. In this study, novel microbial embedding gel beads were produced with the additional agent of cyclodextrin (CD). Results show that CD could increase the mass transfer of OTC into gel beads, possibly because of its strong affinity for organic matters. In terms of OTC biodegradation, gel beads with CD were comparable to gel beads without CD, while the former’s sucrose removal efficiency was higher than the latter. The biodegradation of OTC only occurred in the presence of sucrose. The respiration test also confirmed these findings. Overall, the produced novel gel beads modified with CD could improve the removal performance of OTC.

  17. Formulation of a poly herbal gel for uterus flux

    Directory of Open Access Journals (Sweden)

    M. Rezghi

    2017-11-01

    Full Text Available Background and objectives: Over the centuries, herbal drugs have been used as major sources of medicine for the prevention and treatment of diseases. In recent years, there has been an exponential growth in the field of herbal medicines and these drugs are gaining popularity both in developing and developed countries because of their natural origin and less side effects. The present research has been undertaken to formulate and evaluate an herbal gel for uterus flux based on Iranian traditional medicine references. Methods: An aqueous extracts of fruit peels of Punica granatum and leaves of Myrtus communis, ethanol extract of oleo gum resins of Boswellia carterii and hydro-alcoholic extract of Carum carvi fruits were obtained. The gel was prepared by using the plants extract, carbopol 940, propylene glycol, tri-ethanolamine and distilled water. Further, the prepared gel was evaluated for physicochemical and microbial characteristics. Moreover, accelerated laboratory stability tests were performed. Results: The results showed good appearance and homogeneity of the gel. It was yellow-brown in color with acceptable physicochemical characteristics. Besides, the gel was stable towards physical changes and successfully passed microbiological tests. Conclusion: The prepared gel contained tannins which are astringent agents; therefore, this product could be an appropriate candidate for disorders like uterus flux with respect to its traditional use.

  18. 99mTc gel generators based on zirconium molybdate-99Mo: III: Influence of preparatory conditions of zirconium molybdate-99Mo gel on generator performance

    International Nuclear Information System (INIS)

    Saraswathy, P.; Sarkar, S.K.; Arjun, G.; Ramamoorthy, N.; Nandy, S.K.

    2004-01-01

    The effect of subtle variations on zirconium molybdate- 99 Mo gel preparatory conditions, such as stoichiometry of reactants, pH of gel formation, conditioning of gel granules etc., prior to elution were investigated primarily to arrive at the conditions resulting in high 99m Tc release and minimal 99 Mo breakthrough upon elution with normal saline. Zirconium molybdate- 99 Mo gels were prepared by reacting solutions of Zr and Mo in mole ratios of 0.75-1.5. Both water and normal saline were used for gel disintegration, and the release of 99m Tc and 99 Mo from gel columns into eluates was compared. Sharper elution profile of 99m Tc, but with significantly higher 99 Mo breakthrough (5-8 times), was obtained when water alone was used for disintegration and elution, in comparison to when saline was used. Gels exhibiting optimum characteristics were found to be formed at a pH of 4-5 by reacting [Zr]: [Mo] in the mole ratio of 1.25: 1 and after drying, the product was dispersed into granules by disintegration with normal saline. 99m Tc elution efficiency was found to be ∝ 75% and 99 Mo breakthrough ∝ 0.05%. The elution profile was sharp when a 6 g gel column coupled to a 2 g acidic alumina column (to trap 99 Mo) was eluted with 6-9 ml normal saline. Generators containing upto 23 GBq 99 Mo were prepared, eluted extensively without changing the alumina column and found to provide pertechnetate of good quality, commensurate with hospital radiopharmacy requirements. (orig.)

  19. Study on the kinetics of gel formation in the radiation crosslinking reaction

    International Nuclear Information System (INIS)

    Wang Mingjun; Liu Yuming

    1988-01-01

    From the kinetic equation of gel formation obtained by the authors, the mechanism of gel formation may be interpreted clearly as follows: (1) When the degree of crosslinking q g , the system is sol and the crosslinking reaction is only carried out between the sol molecules. (q g is the gel point). (2) When q=q g , there exists a beginning point where the gel is coexisted with the sol, and the system is still sol, and the crosslinking reaction is still carried out between the sol molecules. (3) When q>q g , the crosslinking reaction exceeds the gel point and the gel is coexisted with the sol. The kinetic equation shows clearly that the transformation from sol into gel is caused by crosslinking reaction of the uncrosslinked chain units between the sol and gel molecules. As a result the sol molecules are transformed into the gel molecules gradually, and the sol fraction is reduced. When the chain units P-barw(s)S(1-s)dq in sol are crosslinked with gel, the sol fraction in the system is reduced ds (where P-barw(s) is a function of the radiation dose and s is sol frection). The degree of crosslinking per unit dose (q 0 ) is a reduced function of dose (R). The equation for calculating its value for every irradiation dose is obtained. After knowing the correlation between P-bar W(s) vs R and q 0 vs R, the distribution of gel and sol in the process of radiation crosslinking can be discussed as well

  20. Two-dimensional polyacrylamide gel analysis of Plodia interpunctella granulosis virus

    International Nuclear Information System (INIS)

    Russell, D.L.; Consigli, R.A.

    1986-01-01

    The structural polypeptides of purified Plodia interpunctella granulosis virus were analyzed by three different two-dimensional gel systems. Isoelectric focusing followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed resolution of 53 acidic polypeptides in the enveloped nucleocapsid of the virus ranging in molecular weight from 97,300 to 8000. Nine of these polypeptides were shown to be glycoproteins by the technique of radiolabeled lectin blotting. Separation of the granulin in this system allowed resolution of five species, all of which have identical tryptic peptide maps. This matrix protein was demonstrated to be a phosphoglycoprotein by radiolabeled lectin blotting and acid phosphatase dephosphorylation. Nonequilibrium pH gel electrophoresis followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed resolution of the major basic protein of the virus, VP12, from a more acidic protein of the same molecular weight. Tryptic peptide analysis demonstrated that these two proteins were indeed different and acid urea gels followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis allowed localization of the acidic protein to the envelope and the basic protein to the nucleocapsid of the virus. Finally, probing of the separated envelope nucleocapsid proteins in both the isoelectric focusing and nonequilibrium pH gel electrophoresis two-dimensional systems after transfer to nitrocellulose with iodinated, purified viral proteins allowed further insight into reactions which may be important in the maintenance of the virion structure

  1. Modelling the behaviour of the push-pull gel dosimeter

    International Nuclear Information System (INIS)

    Bosi, S.G.; Davies, J.B.; Gorjiara, T.; Baldock, C.

    2010-01-01

    Full text: Recent development of a gel dosimeter based on the radiobleaching pigment, genipin, allows development of a new 3D optically scanned gel dosimeter-the p ush-pull g el. This gel would contain two spectrally complementary pigments, one which darkens with dose and another (e.g. genipin) which bleaches. The two pigments deal separately with the high and low dose ends of the dosimeter's dynamic range. The bleaching pigment would be optimised for high sensitivity and the darkening pigment for low. Employing dual pigments, optimised independently, relaxes the need for compromise between sensitivity at low dose and accuracy at high dose. Such a gel, after exposure, would be read using two successive optical CT scans, at two different wavelengths. The reduction in sensitivity of the darkening pigment (allowed by the use of push-pull) would reduce the occurrence of regions of high optical attenuation which can generate optical CT artefacts. Simulated optical CT reconstructions of the optical density map (Fig. La) scanned at the darkening pigment wavelength of a hypothetical push-pull gel, confirms the reduction in susceptibility to artefacts. Fig. I b shows a profile through the map with no stray light added. The centre of the profile in Fig. I d shows a cupping artefact produced by 10 ppm of stray light. The similarity of Fig. Ic and b show that a 30% sensitivity reduction allowed by push-pull, renders the artefact negligible. This paper presents the results of' these simulations of a push-pull gel scanned using optical CT and also some results of experiments with genipin gel. (author)

  2. Crystallization of Na2O-SiO2 gel and glass

    Science.gov (United States)

    Neilson, G. F.; Weinberg, M. C.

    1984-01-01

    The crystallization behavior of a 19 wt pct soda silica gel and gel-derived glass was compared to that of the ordinary glass of the same composition. Both bulk and ground glass samples were utilized. X-ray diffraction measurements were made to identify the crystalline phases and gauge the extent of crystallization. It was found that the gel crystallized in a distinctive manner, while the gel glass behavior was not qualitatively different from that of the ordinary glass.

  3. Evaluation of wheat by polyacrylamide gel electrophoresis | Shuaib ...

    African Journals Online (AJOL)

    ... polyacrylamide gel electrophoresis (SDS-PAGE). Electrophorogram for each variety were scored and presence or absence of each band noted and was entered in a binary data matrix. Based on the data of SDS-PAGE gels cluster analysis was performed to check the variations among varieties. The overall result shows ...

  4. Evolution of heterogeneity accompanying sol-gel transitions in a supramolecular hydrogel.

    Science.gov (United States)

    Matsumoto, Yuji; Shundo, Atsuomi; Ohno, Masashi; Tsuruzoe, Nobutomo; Goto, Masahiro; Tanaka, Keiji

    2017-10-18

    When a peptide amphiphile is dispersed in water, it self-assembles into a fibrous network, leading to a supramolecular hydrogel. When the gel is physically disrupted by shaking, it transforms into a sol state. After aging at room temperature for a while, it spontaneously returns to the gel state, called sol-gel transition. However, repeating the sol-gel transition often causes a change in the rheological properties of the gel. To gain a better understanding of the sol-gel transition and its reversibility, we herein examined the thermal motion of probe particles at different locations in a supramolecular hydrogel. The sol obtained by shaking the gel was heterogeneous in terms of the rheological properties and the extent decreased with increasing aging time. This time course of heterogeneity, or homogeneity, which corresponded to the sol-to-gel transition, was observed for the 1st cycle. However, this was not the case for the 2nd and 3rd cycles; the heterogeneity was preserved even after aging. Fourier-transform infrared spectroscopy, small-angle X-ray scattering, and atomic force and confocal laser scanning microscopies revealed that, although the molecular aggregation states of amphiphiles both in the gel and sol remained unchanged with the cycles, the fibril density diversified to high and low density regions even after aging. The tracking of particles with different sizes indicated that the partial mesh size in the high density region and the characteristic length scale of the density fluctuation were smaller than 50 nm and 6 μm, respectively.

  5. Study of gel grown mixed crystals of Bax Ca ((IO3) 4

    Indian Academy of Sciences (India)

    The growth of mixed crystals of BaCa1–(IO3)4 were carried out with simple gel method. The effect of various parameters such as pH of gel solution, gel concentration, gel setting time, concentration of reactants on the growth was studied. Crystals having different morphologies and habits were obtained. The grown ...

  6. Entrapment of Probiotics in Water Extractable Arabinoxylan Gels: Rheological and Microstructural Characterization

    Directory of Open Access Journals (Sweden)

    Adriana Morales-Ortega

    2014-03-01

    Full Text Available Due to their porous structure, aqueous environment and dietary fiber nature arabinoxylan (AX gels could have potential applications for colon-specific therapeutic molecule delivery. In addition, prebiotic and health related effects of AX have been previously demonstrated. It has been also reported that cross-linked AX can be degraded by bacteria from the intestinal microbiota. However, AX gels have not been abundantly studied as carrier systems and there is no information available concerning their capability to entrap cells. In this regard, probiotic bacteria such as Bifidobacterium longum have been the focus of intense research activity lately. The objective of this research was to investigate the entrapment of probiotic B. longum in AX gels. AX solution at 2% (w/v containing B. longum (1 × 107 CFU/cm formed gels induced by laccase as cross-linking agent. The entrapment of B. longum decreased gel elasticity from 31 to 23 Pa, probably by affecting the physical interactions taking place between WEAX chains. Images of AX gels containing B. longum viewed under a scanning electron microscope show the gel network with the bacterial cells entrapped inside. The microstructure of these gels resembles that of an imperfect honeycomb. The results suggest that AX gels can be potential candidates for the entrapment of probiotics.

  7. Influence of the gel thickness on in vivo hyaline cartilage regeneration induced by double-network gel implanted at the bottom of a large osteochondral defect: Short-term results

    Directory of Open Access Journals (Sweden)

    Matsuda Hidetoshi

    2013-01-01

    Full Text Available Abstract Background A double-network (DN gel, which is composed of poly(2-acrylamido-2-methylpropanesulfonic acid and poly(N,N’-dimethyl acrylamide, can induce hyaline cartilage regeneration in vivo in a large osteochondral defect. The purpose of this study was to clarify the influence of the thickness of the implanted DN gel on the induction ability of hyaline cartilage regeneration. Methods Thirty-eight mature rabbits were used in this study. We created an osteochondral defect having a diameter of 4.3-mm in the patellofemoral joint. The knees were randomly divided into 4 groups (Group I: 0.5-mm thick gel, Group II: 1.0-mm thick gel, Group III: 5.0-mm thick gel, and Group IV: untreated control. Animals in each group were further divided into 3 sub-groups depending on the gel implant position (2.0-, 3.0-, or 4.0-mm depth from the articular surface in the defect. The regenerated tissues were evaluated with the Wayne’s gross and histological grading scales and real time PCR analysis of the cartilage marker genes at 4 weeks. Results According to the total Wayne’s score, when the depth of the final vacant space was set at 2.0 mm, the scores in Groups I, II, and III were significantly greater than that Group IV (p  Conclusions The 1.0-mm thick DN gel sheet had the same ability to induce hyaline cartilage regeneration as the 5.0-mm thick DN gel plug. However, the induction ability of the 0.5-mm thick sheet was significantly lower when compared with the 1.0-mm thick gel sheet. The 1.0-mm DN gel sheet is a promising device to establish a cell-free cartilage regeneration strategy that minimizes bone loss from the gel implantation.

  8. SU-E-T-753: Three-Dimensional Dose Distributions of Incident Proton Particle in the Polymer Gel Dosimeter and the Radiochromic Gel Dosimeter: A Simulation Study with MCNP Code

    International Nuclear Information System (INIS)

    Park, M; Kim, G; Ji, Y; Kim, K; Park, S; Jung, H

    2015-01-01

    Purpose: The purpose of this study is to estimate the three-dimensional dose distributions in the polymer and the radiochromic gel dosimeter, and to identify the detectability of both gel dosimeters by comparing with the water phantom in case of irradiating the proton particles. Methods: The normoxic polymer gel and the LCV micelle radiochromic gel were used in this study. The densities of polymer and the radiochromic gel dosimeter were 1.024 and 1.005 g/cm 3 , respectively. The dose distributions of protons in the polymer and radiochromic gel were simulated using Monte Carlo radiation transport code (MCNPX, Los Alamos National Laboratory). The shape of phantom irradiated by proton particles was a hexahedron with the dimension of 12.4 × 12.4 × 15.0 cm 3 . The energies of proton beam were 50, 80, and 140 MeV energies were directed to top of the surface of phantom. The cross-sectional view of proton dose distribution in both gel dosimeters was estimated with the water phantom and evaluated by the gamma evaluation method. In addition, the absorbed dose(Gy) was also calculated for evaluating the proton detectability. Results: The evaluation results show that dose distributions in both gel dosimeters at intermediated section and Bragg-peak region are similar with that of the water phantom. At entrance section, however, inconsistencies of dose distribution are represented, compared with water. The relative absorbed doses in radiochromic and polymer gel dosimeter were represented to be 0.47 % and 2.26 % difference, respectively. These results show that the radiochromic gel dosimeter was better matched than the water phantom in the absorbed dose evaluation. Conclusion: The polymer and the radiochromic gel dosimeter show similar characteristics in dose distributions for the proton beams at intermediate section and Bragg-peak region. Moreover the calculated absorbed dose in both gel dosimeters represents similar tendency by comparing with that in water phantom

  9. New insights into uranium (VI) sol-gel processing

    International Nuclear Information System (INIS)

    King, C.M.; Thompson, M.C.; Buchanan, B.R.; King, R.B.; Garber, A.R.

    1990-01-01

    Nuclear Magnetic Resonance (NMR) investigations on the Oak Ridge National Laboratory process for sol-gel synthesis of microspherical nuclear fuel (UO 2 ), has been extremely useful in sorting out the chemical mechanism in the sol-gel steps. 13 C, 15 N, and 1 H NMR studies on the HMTA gelation agent (Hexamethylene tetramine, C 6 H 12 N 4 ) has revealed near quantitative stability of this adamantane-like compound in the sol-gel process, contrary to its historical role as an ammonia source for gelation from the worldwide technical literature. 17 O NMR of uranyl (UO 2 ++ ) hydrolysis fragments produced in colloidal sols has revealed the selective formation of a uranyl trimer, [(UO 2 ) 3 (μ 3 -O)(μ 2 -OH) 3 ] + , induced by basic hydrolysis with the HMTA gelation agent. Spectroscopic results will be presented to illustrate that trimer condensation occurs during sol-gel processing leading to layered polyanionic hydrous uranium oxides in which HMTAH + is occluded as an ''intercalation'' cation. Subsequent sol-gel processing of microspheres by ammonia washing results in in-situ exchange and formation of a layered hydrous ammonium uranate with a proposed structural formula of (NH 4 ) 2 [(UO 2 ) 8 O 4 (OH) 10 ] · 8H 2 O. This compound is the precursor to sintered UO 2 ceramic fuel. 23 refs., 10 figs

  10. Normal modes of weak colloidal gels

    Science.gov (United States)

    Varga, Zsigmond; Swan, James W.

    2018-01-01

    The normal modes and relaxation rates of weak colloidal gels are investigated in calculations using different models of the hydrodynamic interactions between suspended particles. The relaxation spectrum is computed for freely draining, Rotne-Prager-Yamakawa, and accelerated Stokesian dynamics approximations of the hydrodynamic mobility in a normal mode analysis of a harmonic network representing several colloidal gels. We find that the density of states and spatial structure of the normal modes are fundamentally altered by long-ranged hydrodynamic coupling among the particles. Short-ranged coupling due to hydrodynamic lubrication affects only the relaxation rates of short-wavelength modes. Hydrodynamic models accounting for long-ranged coupling exhibit a microscopic relaxation rate for each normal mode, λ that scales as l-2, where l is the spatial correlation length of the normal mode. For the freely draining approximation, which neglects long-ranged coupling, the microscopic relaxation rate scales as l-γ, where γ varies between three and two with increasing particle volume fraction. A simple phenomenological model of the internal elastic response to normal mode fluctuations is developed, which shows that long-ranged hydrodynamic interactions play a central role in the viscoelasticity of the gel network. Dynamic simulations of hard spheres that gel in response to short-ranged depletion attractions are used to test the applicability of the density of states predictions. For particle concentrations up to 30% by volume, the power law decay of the relaxation modulus in simulations accounting for long-ranged hydrodynamic interactions agrees with predictions generated by the density of states of the corresponding harmonic networks as well as experimental measurements. For higher volume fractions, excluded volume interactions dominate the stress response, and the prediction from the harmonic network density of states fails. Analogous to the Zimm model in polymer

  11. Antibacterial Inhibitory Effects of Punica Granatum Gel on Cariogenic Bacteria: An in vitro Study.

    Science.gov (United States)

    Millo, Grazielle; Juntavee, Apa; Ratanathongkam, Ariya; Nualkaew, Natsajee; Peerapattana, Jomjai; Chatchiwiwattana, Supaporn

    2017-01-01

    This study evaluated the in vitro antibacterial effects of the formulated Punica granatum (PG) gel against Streptococcus mutans, Streptococcus sanguinis, and Lactobacillus casei. The PG extract was dissolved in water at 500 mg/mL. High performance liquid chromatography (HPLC) was used for identification and quantification of chemical marker punicalagin. Minimum bactericidal concentration (MBC) and time-kill assay (TKA) were investigated. Antibacterial activities of the formulated PG gel, 2% chlorhexidine (CHX) gel and blank gel were tested by measuring the zones of inhibition through agar well diffusion method. The HPLC results showed presence of punicalagin at 2023.58 ± 25.29 pg/mL in the aqueous PG extract and at 0.234% (w/w) in the formulated PG gel. The MBC for S. mutans, S. Sanguinis, and L. casei were 250, 125, and 500 mg/mL respectively. The TKA of 500 mg/mL aqueous PG extract showed total inhibition of S. mutans, S. Sanguinis, and L. casei at 6, 1, and 24 hours contact time respectively. Agar well diffusion revealed that for S. mutans, CHX gel > PG gel > blank gel; for S. sanguinis, CHX gel = PG gel > blank gel; for L. casei, CHX gel > PG gel = blank gel. Comparison of the PG gel potency showed that S. sanguinis = S. mutans > L. casei. The PG gel equivalent to 0.234% punicalagin (w/w) inhibited S. mutans and S. sanguinis but not L. casei within 24 hours incubation period and has the potential to be used for caries prevention. Millo G, Juntavee A, Ratanathongkam A, Nualkaew N, Peerapattana J, Chatchiwiwattana S. Antibacterial Inhibitory Effects of Punica Granatum Gel on Cariogenic Bacteria: An in vitro Study. Int J Clin Pediatr Dent 2017;10(2):152-157.

  12. Colloidal probe dynamics in gelatin solution during the sol-gel transition.

    Science.gov (United States)

    Hong, Wei; Xu, Guozhi; Ou, Xiaogang; Sun, Weixiang; Wang, Tao; Tong, Zhen

    2018-05-16

    The dynamics of the colloidal probes in a gelatin solution during the time-dependent sol-gel transition was investigated by multi-particle tracking. The relationship between the relaxation of the medium at the critical gel point and the mean square displacement of the probes was elucidated. Based on this understanding, the critical gel point of gelatin and the corresponding critical exponent n were unambiguously determined by the loss angle criterion and the time-cure superposition. The shift factors of the latter are further used to estimate the time/length-scale evolution of the gelatin during the sol-gel transition. The growth of the medium length scale crossed with the two measuring length scales successively at the pre-gel regime. Coinciding with the length-scale crossovers, the probability density function (PDF) of the probe displacements displayed two transient peaks of non-Gaussianity. In the post-gel regime, the third peak of Gaussianity suggested inhomogeneity in the gel network. The non-Gaussianity results from the bifurcation of diffusivity. The present work showed that the non-Gaussian dynamics of the probes are not the direct equivalence of that of the medium, but an effect of length-scale coupling.

  13. Viscoelastic nature of Au nanoparticle–PDMS nanocomposite gels

    Indian Academy of Sciences (India)

    A stable gel of Au nanoparticles in polydimethylsiloxane (PDMS) nanocomposite is prepared by employing the curing agent of PDMS elastomer as a reducing agent for the formation of Au nanoparticles by an in-situ process. The viscoelastic nature of these gels is very sensitive to the Au nanoparticle loading and the ...

  14. Preparation And Evaluation Of Fluconazole Gels | Abdel-Mottaleb ...

    African Journals Online (AJOL)

    Gels dosage forms are successfully used as drug delivery systems considering their ability to control drug release and to protect medicaments from a hostile environment. Thus, it was desired in this study to formulate fluconazole into a gel that could be used locally in the treatment of different skin fungal infections. Cellulose ...

  15. Development and evaluation of ibuprofen transdermal gel formulations

    African Journals Online (AJOL)

    A commercial ibuprofen gel product (Ibutop®) was used as a reference. Results: The formulations containing 5 % of either menthol or glycerol as permeation enhancers gave drug release patterns comparable to that of the reference product. Propanol increased the apparent viscosity of the test gels to the same extent as that ...

  16. Dosimetric characteristics of PASSAG as a new polymer gel dosimeter with negligible toxicity

    Science.gov (United States)

    Farhood, Bagher; Abtahi, Seyed Mohammad Mahdi; Geraily, Ghazale; Ghorbani, Mehdi; Mahdavi, Seied Rabi; Zahmatkesh, Mohammad Hasan

    2018-06-01

    Despite many advantages of polymer gel dosimeters, their clinical use is only not realized now. Toxicity of polymer gel dosimeters can be considered as one of their main limitations for use in routine clinical applications. In the current study, a new polymer gel dosimeter is introduced with negligible toxicity. For this purpose, 2-Acrylamido-2-Methy-1-PropaneSulfonic acid (AMPS) sodium salt monomer was replaced instead of acrylamide monomer used in PAGAT gel dosimeter by using %6 T and %50 C to the gel formula and the new formulation is called PASSAG (Poly AMPS Sodium Salt and Gelatin) polymer gel dosimeter. The irradiation of gel dosimeters was carried out using a Co-60 therapy machine. MRI technique was used to quantify the dose responses of the PASSAG gel dosimeter. Then, the MRI responses (R2) of the gel dosimeter was analyzed at different dose values, post-irradiation times, and scanning temperatures. The results showed that the new gel formulation has a negligible toxicity and it is also eco-friendly. In addition, carcinogenicity and genetic toxicity tests are negative for the monomer used in PASSAG. The radiological properties of PASSAG gel dosimeter showed that this substance can be considered as a soft tissue/water equivalent material. Furthermore, dosimetric evaluation of the new polymer gel dosimeter revealed an excellent linear R2-dose response in the evaluated dose range (0-15 Gy). The R2-dose sensitivity and dose resolution of PASSAG gel dosimeter were 0.081 s-1Gy-1 (in 0-15 Gy dose range) and 1 Gy (in 0-10 Gy dose range), respectively. Moreover, it was shown that the R2-dose sensitivity and dose resolution of the new gel dosimeter improves over time after irradiation. It was also found that the R2 response of the PASSAG gel dosimeter has less dependency to the 18, 20, and 24 °C scanning temperature in comparison to that of room temperature (22 °C).

  17. Effectiveness of Gel Repellents on Feral Pigeons

    Directory of Open Access Journals (Sweden)

    Birte Stock

    2013-12-01

    Full Text Available Millions of feral pigeons (Columba livia live in close association with the human population in our cities. They pose serious health risks to humans and lead to high economic loss due to damage caused to buildings. Consequently, house owners and city authorities are not willing to allow pigeons on their buildings. While various avian repellents are regularly introduced onto the market, scientific proof of efficacy is lacking. This study aimed at testing the effectiveness of two avian gel repellents and additionally examined their application from animal welfare standpoint. The gels used an alleged tactile or visual aversion of the birds, reinforced by additional sensory cues. We mounted experimental shelves with the installed repellents in a pigeon loft and observed the behavior of free-living feral pigeons towards the systems. Both gels showed a restricted, transient repellent effect, but failed to prove the claimed complete effectiveness. Additionally, the gels’ adhesive effect remains doubtful in view of animal welfare because gluing of plumage presents a risk to feral pigeons and also to other non-target birds. This study infers that both gels lack the promised complete efficacy, conflict with animal welfare concerns and are therefore not suitable for feral pigeon management in urban areas.

  18. Slow Release of Plant Volatiles Using Sol-Gel Dispensers.

    Science.gov (United States)

    Bian, L; Sun, X L; Cai, X M; Chen, Z M

    2014-12-01

    The black citrus aphid, also known as the tea aphid, (Toxoptera aurantii Boyer) attacks economically important crops, including tea (Camellia sinensis (L.) O. Kuntze). In the current study, silica sol-gel formulations were screened to find one that could carry and release C. sinensis plant volatiles to lure black citrus aphids in a greenhouse. The common plant volatile trans-2-hexen-1-al was used as a model molecule to screen for suitable sol-gel formulations. A zNose (Electronic Sensor Technology, Newbury Park, CA) transportable gas chromatograph was used to continuously monitor the volatile emissions. A sol-gel formulation containing tetramethyl orthosilicate and methyltrimethoxysilane in an 8:2 (vol:vol) ratio was selected to develop a slow-release dispenser. The half-life of trans-2-hexen-1-al in the sol-gel dispenser increased slightly with the volume of this compound in the dispenser. Ten different volatiles were tested in the sol-gel dispenser. Alcohols of 6-10 carbons had the longest half-lives (3.01-3.77 d), while esters of 6-12 carbons had the shortest (1.53-2.28 d). Release of these volatiles from the dispensers could not be detected by the zNose after 16 d (cis-3-hexenyl acetate) to 26 d (3,7-dimethylocta-1,6-dien-3-ol). In greenhouse experiments, trans-2-hexen-1-al and cis-3-hexen-1-ol released from the sol-gel dispensers attracted aphids for ≍17 d, and release of these volatiles could not be detected by the zNose after ≍24 d. The sol-gel dispensers performed adequately for the slow release of plant volatiles to trap aphids in the greenhouse. © 2014 Entomological Society of America.

  19. Sol-gel encapsulation for controlled drug release and biosensing

    Science.gov (United States)

    Fang, Jonathan

    The main focus of this dissertation is to investigate the use of sol-gel encapsulation of biomolecules for controlled drug release and biosensing. Controlled drug release has advantages over conventional therapies in that it maintains a constant, therapeutic drug level in the body for prolonged periods of time. The anti-hypertensive drug Captopril was encapsulated in sol-gel materials of various forms, such as silica xerogels and nanoparticles. The primary objective was to show that sol-gel silica materials are promising drug carriers for controlled release by releasing Captopril at a release rate that is within a therapeutic range. We were able to demonstrate desired release for over a week from Captopril-doped silica xerogels and overall release from Captopril-doped silica nanoparticles. As an aside, the antibiotic Vancomycin was also encapsulated in these porous silica nanoparticles and desired release was obtained for several days in-vitro. The second part of the dissertation focuses on immobilizing antibodies and proteins in sol-gel to detect various analytes, such as hormones and amino acids. Sol-gel competitive immunoassays on antibody-doped silica xerogels were used for hormone detection. Calibration for insulin and C-peptide in standard solutions was obtained in the nM range. In addition, NASA-Ames is also interested in developing a reagentless biosensor using bacterial periplasmic binding proteins (bPBPs) to detect specific biomarkers, such as amino acids and phosphate. These bPBPs were doubly labeled with two different fluorophores and encapsulated in silica xerogels. Ligand-binding experiments were performed on the bPBPs in solution and in sol-gel. Ligand-binding was monitored by fluorescence resonance energy transfer (FRET) between the two fluorophores on the bPBP. Titration data show that one bPBP has retained its ligand-binding properties in sol-gel.

  20. An intelligent biopolymer gel with pendant L-proline methyl ester

    International Nuclear Information System (INIS)

    Yoshida, Masaru; Safranj, A.; Omichi, Hideki; Katakai, Ryoichi.

    1995-01-01

    Linear poly(acryloyl-L-proline methyl ester, A-ProOMe), obtained by radiation-induced polymerization of its monomer in ethanol, exhibits a lower critical solution temperature (LCST) at 14degC. A-ProOMe was copolymerized with a minor amount of 2-hydroxypropyl methacrylate (HPMA) or 2-hydroxyethyl methacrylate (HEMA), to obtain intelligent biopolymer gels for application in drug delivery systems. The poly(A-ProOMe/HPMA) gel was characterized by an initial rapid shrinkage at the surface in the swollen state, as resulting in formation of a rigid membrane barrier devoid of micropores. This gel is called a surface regulated matrix. In the case of poly(A-ProOMe/HEMA), no such a barrier formed, instead, the whole matrix shrunk without the disappearance of micropores. This gel is called a matrix pumping gel. Testosterone (T) was incorporated into the poly(A-ProOMe/HPMA) gel, and it was found that the daily dose of T released in vivo from this formulation remained constant at approximately 30 μg/day throughout an experimental period of 54 weeks. On the other hand, 9-β-D-arabinofuranosyladenine (Ara-A) was incorporated into the poly(A-ProOMe/HEMA) gel to evaluate the pulsatile drug release when cycled at 10 and 37degC. The in vitro release rate of Ara-A was found to be 11 ng/h at 10degC and 33 ng/h at 37degC. (author)

  1. Use of normoxic polymer gel dosimeters for measuring diagnostic doses on CT scanners

    International Nuclear Information System (INIS)

    Hill, B; Venning, A J; Baldock, C

    2004-01-01

    X-ray CT has been used to evaluate polymer gel dosimeters for dose response in the therapeutic dose range. This method of polymer gel dosimeter evaluation has been shown to be useful for instance in the comparison of complex sterotactic field distributions with treatment plans. Image averaging and subtraction techniques are used for noise reduction in polymer gel dosimeters resulting in the delivery of several CT slices across the polymer gel dosimeters. It was a logical progression to evaluate normoxic polymer gel dosimeters with optimized CT scanning protocols. During these investigations it was found that unirradiated regions in irradiated normoxic polymer gel dosimetry phantoms polymerised possibly as a result of the evaluation using CT. This prompted an investigation of the CT diagnostic dose response of the normoxic polymer gel dosimeter in order to determine the dose contribution when evaluated using a CT scanner. Having established that there was an effect on the normoxic polymer gel dosimeter when evaluating with a CT scanner the suitability of these gels in the determination of CT diagnostic dose measurement was further investigated

  2. Sol-Gel Chemistry for Carbon Dots.

    Science.gov (United States)

    Malfatti, Luca; Innocenzi, Plinio

    2018-03-14

    Carbon dots are an emerging class of carbon-based nanostructures produced by low-cost raw materials which exhibit a widely-tunable photoluminescence and a high quantum yield. The potential of these nanomaterials as a substitute of semiconductor quantum dots in optoelectronics and biomedicine is very high, however they need a customized chemistry to be integrated in host-guest systems or functionalized in core-shell structures. This review is focused on recent advances of the sol-gel chemistry applied to the C-dots technology. The surface modification, the fine tailoring of the chemical composition and the embedding into a complex nanostructured material are the main targets of combining sol-gel processing with C-dots chemistry. In addition, the synergistic effect of the sol-gel precursor combined with the C-dots contribute to modify the intrinsic chemo-physical properties of the dots, empowering the emission efficiency or enabling the tuning of the photoluminescence over a wide range of the visible spectrum. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Highly-correlated charges in polyelectrolyte gels

    Science.gov (United States)

    Sing, Charles; Zwanikken, Johannes; Olvera de La Cruz, Monica

    2013-03-01

    Polyelectrolyte gels are ubiquitous in polymer physics due to their attractive combination of structural and chemical features that permit the realization of ``environmentally responsive'' systems. The conventional conceptual picture of the volume response of these systems is based on a competition between osmotic and elastic effects. We elaborate on this fundamental understanding by including ion correlations through the use of liquid-state integral equation theory. This allows for a statistical mechanical representation of the state of the system that not only surpasses traditional Poisson-Boltzmann theories but also renders structural features in a highly accurate fashion. In particular, the local ion structure is elucidated, allowing for detailed articulation of charge inversion and condensation effects in the context of gel swelling. The inclusion of correlations has a number of ramifications that become apparent, with enhanced gel collapse and excluded volume competitions that give rise to novel and ion-dependent reentrant swelling effects. We expect this rigorous theory to prove instructive in understanding any number of gelated structures, such as chromosomes or designed synthetic materials for drug delivery.

  4. Correlation between ionic conductivity and fluidity of polymer gel ...

    Indian Academy of Sciences (India)

    Unknown

    Ionic conductivity; ion aggregates; FTIR spectroscopy; gels; fluidity. 1. Introduction ... liquid and polymer gel electrolytes have been studied as functions of salt ..... Ratner M A 1987 in Polymer electrolyte reviews (eds) J R. MacCallum and C A ...

  5. XEN Gel Implant: a new surgical approach in glaucoma.

    Science.gov (United States)

    Chaudhary, Ankita; Salinas, Lauriane; Guidotti, Jacopo; Mermoud, André; Mansouri, Kaweh

    2018-01-01

    Glaucoma is a leading cause of blindness worldwide. Intraocular pressure (IOP) lowering is the only effective treatment strategy. Traditional glaucoma surgeries are generally considered to be unpredictable and associated with a high rate of complications. This has led to the development of a novel XEN Gel Implant, a type of minimally invasive glaucoma surgery (MIGS), lowering the IOP without extensive surgical dissection. Areas covered: A literature search was undertaken on PubMed using the terms XEN glaucoma, gelatin microstent, and MIGS. All the articles and case reports on XEN Gel Implant and selected articles on MIGS were studied and reviewed. We have discussed the results of most studies on XEN Gel Implant related to its efficacy, safety and success. Expert commentary: The XEN Gel Implant effectively lowers IOP and medication use, with a favorable safety profile. Long-term data on its success and cost-effectiveness are lacking. The studies have shown it to be without any serious adverse events and to have good safety profile encouraging future research on this novel implant. There is a need to correctly identify selection criteria for patients, who would benefit the most from the XEN Gel Implant.

  6. Comparative gel-based phosphoproteomics in response to signaling molecules

    KAUST Repository

    Marondedze, Claudius; Lilley, Kathryn S.; Thomas, Ludivine

    2013-01-01

    The gel-based proteomics approach is a valuable technique for studying the characteristics of proteins. This technique has diverse applications ranging from analysis of a single protein to the study of the total cellular proteins. Further, protein quality and to some extent distribution can be first assessed by means of one-dimensional gel electrophoresis and then more informatively, for comparative analysis, using the two-dimensional gel electrophoresis technique. Here, we describe how to take advantage of the availability of fluorescent dyes to stain for a selective class of proteins on the same gel for the detection of both phospho- and total proteomes. This enables the co-detection of phosphoproteins as well as total proteins from the same gel and is accomplished by utilizing two different fluorescent stains, the ProQ-Diamond, which stains only phosphorylated proteins, and Sypro Ruby, which stains the entire subset of proteins. This workflow can be applied to gain insights into the regulatory mechanisms induced by signaling molecules such as cyclic nucleotides through the quantification and subsequent identification of responsive phospho- and total proteins. © Springer Science+Business Media New York 2013.

  7. Comparative gel-based phosphoproteomics in response to signaling molecules

    KAUST Repository

    Marondedze, Claudius

    2013-09-03

    The gel-based proteomics approach is a valuable technique for studying the characteristics of proteins. This technique has diverse applications ranging from analysis of a single protein to the study of the total cellular proteins. Further, protein quality and to some extent distribution can be first assessed by means of one-dimensional gel electrophoresis and then more informatively, for comparative analysis, using the two-dimensional gel electrophoresis technique. Here, we describe how to take advantage of the availability of fluorescent dyes to stain for a selective class of proteins on the same gel for the detection of both phospho- and total proteomes. This enables the co-detection of phosphoproteins as well as total proteins from the same gel and is accomplished by utilizing two different fluorescent stains, the ProQ-Diamond, which stains only phosphorylated proteins, and Sypro Ruby, which stains the entire subset of proteins. This workflow can be applied to gain insights into the regulatory mechanisms induced by signaling molecules such as cyclic nucleotides through the quantification and subsequent identification of responsive phospho- and total proteins. © Springer Science+Business Media New York 2013.

  8. Growth and study of barium oxalate single crystals in agar gel

    Indian Academy of Sciences (India)

    Barium oxalate was grown in agar gel at ambient temperature. The effect of various parameters like gel concentration, gel setting time and concentration of the reactants on the growth of these crystals was studied. Prismatic platy shaped spherulites and dendrites were obtained. The grown crystals were characterized by ...

  9. A Practical Use for FXG Gel Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Olding, T; Salomons, G; Darko, J; Schreiner, L J, E-mail: Tim.Olding@krcc.on.c

    2010-11-01

    In-phantom Fricke-xylenol orange-gelatin (FXG) gel dosimetry yields three dimensional (3D) dose data for intensity modulated radiation therapy (IMRT) treatment plan verification within 18-24 hours from the point of request. The information obtained from a 3% dose difference, 3 mm distance-to-agreement gamma function comparison between treatment plan dose and gel-measured dose then provides a useful secondary 3D quality assurance check of the treatment plan prior to delivery.

  10. Production of continuous mullite fiber via sol-gel processing

    Science.gov (United States)

    Tucker, Dennis S.; Sparks, J. Scott; Esker, David C.

    1990-01-01

    The development of a continuous ceramic fiber which could be used in rocket engine and rocket boosters applications was investigated at the Marshall Space Flight Center. Methods of ceramic fiber production such as melt spinning, chemical vapor deposition, and precursor polymeric fiber decomposition are discussed and compared with sol-gel processing. The production of ceramics via the sol-gel method consists of two steps, hydrolysis and polycondensation, to form the preceramic, followed by consolidation into the glass or ceramic structure. The advantages of the sol-gel method include better homogeneity and purity, lower preparation temperature, and the ability to form unique compositions. The disadvantages are the high cost of raw materials, large shrinkage during drying and firing which can lead to cracks, and long processing times. Preparation procedures for aluminosilicate sol-gel and for continuous mullite fibers are described.

  11. Influence of the gel thickness on in vivo hyaline cartilage regeneration induced by double-network gel implanted at the bottom of a large osteochondral defect: short-term results.

    Science.gov (United States)

    Matsuda, Hidetoshi; Kitamura, Nobuto; Kurokawa, Takayuki; Arakaki, Kazunobu; Gong, Jian Ping; Kanaya, Fuminori; Yasuda, Kazunori

    2013-01-31

    A double-network (DN) gel, which is composed of poly(2-acrylamido-2-methylpropanesulfonic acid) and poly(N,N'-dimethyl acrylamide), can induce hyaline cartilage regeneration in vivo in a large osteochondral defect. The purpose of this study was to clarify the influence of the thickness of the implanted DN gel on the induction ability of hyaline cartilage regeneration. Thirty-eight mature rabbits were used in this study. We created an osteochondral defect having a diameter of 4.3-mm in the patellofemoral joint. The knees were randomly divided into 4 groups (Group I: 0.5-mm thick gel, Group II: 1.0-mm thick gel, Group III: 5.0-mm thick gel, and Group IV: untreated control). Animals in each group were further divided into 3 sub-groups depending on the gel implant position (2.0-, 3.0-, or 4.0-mm depth from the articular surface) in the defect. The regenerated tissues were evaluated with the Wayne's gross and histological grading scales and real time PCR analysis of the cartilage marker genes at 4 weeks. According to the total Wayne's score, when the depth of the final vacant space was set at 2.0 mm, the scores in Groups I, II, and III were significantly greater than that Group IV (phyaline cartilage regeneration as the 5.0-mm thick DN gel plug. However, the induction ability of the 0.5-mm thick sheet was significantly lower when compared with the 1.0-mm thick gel sheet. The 1.0-mm DN gel sheet is a promising device to establish a cell-free cartilage regeneration strategy that minimizes bone loss from the gel implantation.

  12. Applying of isoconversional analysis to calorimetric data on the gel melting

    Science.gov (United States)

    Dranca, I.; Lupascu, T.; Povar, I.

    2012-02-01

    The present study is concerned to the thermal stability of gelatin gels that is defined that their resistance to melting or, in other words, to the thermally stimulated transitions from gel to sol. The both sol-gel and gel-sol transitions were followed by regular Mettler-Toledo DSC 823e and stochastically modulated multi-frequency DSC (TOPEM® by Mettler-Toledo). The DSC data have been treated by using an advanced isoconversional method developed by Vyazovkin [1,2]. The method allows revealing a variation in the effective activation energy (Eα) with the extent of conversion (α). It has been discovered that an increase in the concentration of gelatin solutions causes an increase in the energy barrier to melting of non-isothermally prepared gels.

  13. Neutron detector based on lithiated sol-gel glass

    CERN Document Server

    Wallace, S; Miller, L F; Dai, S

    2002-01-01

    A neutron detector technology is demonstrated based on sup 6 Li/ sup 1 sup 0 B doped sol-gel glass. The detector is a sol-gel glass film coated silicon surface barrier detector (SBD). The ionized charged particles from (n, alpha) reactions in the sol-gel film enter the SBD and are counted. Data showing that gamma-ray pulse amplitudes interfere with identifying charged particles that exit the film layer with energies below the gamma-ray energy is presented. Experiments were performed showing the effect of sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co gamma rays on the SBD detector. The reaction product energies of the triton and alpha particles from sup 6 Li are significantly greater than the energies of the Compton electrons from high-energy gamma rays, allowing the measurement of neutrons in a high gamma background. The sol-gel radiation detection technology may be applicable to the characterization of transuranic waste, spent nuclear fuel and to the monitoring of stored plutonium.

  14. MUCOADHESIVE GEL WITH IMMOBILIZED LYSOZYME: PREPARATION AND PROPERTIES

    Directory of Open Access Journals (Sweden)

    Dekina S. S.

    2015-08-01

    Full Text Available The study of non-covalent immobilized lysozyme, as well as physico-chemical and biochemical properties of obtained mucoadhesive gel was the aim of the research. Lysozyme activity was determined by bacteriolytic method (Micrococcus lysodeikticus cells acetone powder was a substrate. Lysozyme immobilization was conducted by the method of entrapment in gel. Enzyme carrier interaction was studied by viscometric, spectrophotometric and spectrofluorimetric methods. Mucoadhesive gel with immobilized lysozyme, possessing antiinflammatory and antimicrobial activities, was prepared. Due to immobilization, protein-polymer complex with the original enzymatic activity was formed. The product is characterized by high mucoadhesive properties, quantitative retaining of protein and bacteriolytic activity, prolonged release of the enzyme, improved biochemical characteristics (extended pH-activity profile, stability in acidic medium and during storage for 2 years, and it is perspective for further studies. The proposed method for lysozyme immobilization in the carboxymethyl cellulose sodium salt gel allows to obtain a stable, highly efficient product, with high adhesive properties for attachment to the mucous membranes, that is promising for use in biomedicine.

  15. Swimming micro-robot powered by stimuli-sensitive gel

    Science.gov (United States)

    Masoud, Hassan; Alexeev, Alexander

    2012-11-01

    Using three-dimensional computer simulations, we design a simple maneuverable micro-swimmer that can self-propel and navigate in highly viscous (low Reynolds-number) environments. Our simple swimmer consists of a cubic gel body which periodically changes volume in response to external stimuli, two rigid rectangular flaps attached to the opposite sides of the gel body, and a flexible steering flap at the front end of the swimmer. The stimuli-sensitive body undergoes periodic expansions (swelling) and contractions (deswelling) leading to a time-irreversible beating motion of the propulsive flaps that propel the micro-swimmer. Thus, the responsive gel body acts as an ``engine'' actuating the motion of the swimmer. We examine how the swimming speed depends on the gel and flap properties. We also probe how the swimmer trajectory can be changed using a responsive steering flap whose curvature is controlled by an external stimulus. We show that the turning occurs due to steering flap bending and periodic beating. Furthermore, our simulations reveal that the turning direction can be regulated by changing the intensity of external stimulus.

  16. A study of correlations between the release of drugs from petrolatum-based gels containing nonionic surfactants and some physical and physico-chemical characteristics of the gel systems.

    Science.gov (United States)

    Colo, G D; Nannipieri, E; Serafini, M F; Vitale, D

    1986-06-01

    Synopsis The in vitro release of benzocaine and 2-ethyIhexyl p-di-methylaminobenzoate (EH-PABA) from petrolatum-based gels either containing two nonionic surfactants, or not, was compared with some physical and/or physico-chemical characteristics of the drugs, the gels and the drug-gel systems. The surfactants had no effect on the release of EH-PABA, the less polar drug, whereas they decreased the release of benzocaine. Moreover, the release data show a complex dependence of diffusive properties of ben-zocaine on drug and surfactant concentration. Benzocaine appears to form mixed micelles with each of the two surfactants and/or undergoes self-aggregation phenomena within surfactant micelles. The results indicate that drug diffusion is influenced by gel porosity, drug molecular size and polarity and molecular interactions. Etude des corrélations entre la disponibilité des medicaments dans les gels a base de vaseline contenant des surfactifs non ioniques et quelques propriétés physiques et physicochimiques des gels.

  17. Ultrasound-assisted sol-gel synthesis of ZrO2.

    Science.gov (United States)

    Guel, Marlene Lariza Andrade; Jiménez, Lourdes Díaz; Hernández, Dora Alicia Cortés

    2017-03-01

    Synthesis of tetragonal ZrO 2 by both conventional sol-gel and ultrasound-assisted sol-gel methods and using a non-ionic surfactant Tween-20, was performed. A porous microstructure composed of nanometric particles was observed. Tetragonal ZrO 2 was obtained using a low heat treatment temperature of powders, 500°C by both methods. A higher crystallinity and a shorter reaction time were observed when ultrasound was used in the sol-gel method due to the cavitation phenomenon. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Solvent exchange-induced in situ forming gel comprising ethyl cellulose-antimicrobial drugs.

    Science.gov (United States)

    Phaechamud, Thawatchai; Mahadlek, Jongjan

    2015-10-15

    Solvent-exchanged in situ forming gel is a drug delivery system which is in sol form before administration. When it contacts with the body fluid, then the water miscible organic solvent dissipates and water penetrates into the system, leading the polymer precipitation as in situ gel at the site of injection. The aim of this research was to study the parameters affecting the gel properties, drug release and antimicrobial activities of the in situ forming gels prepared from ethyl cellulose (EC) dissolved in N-methyl pyrrolidone (NMP) to deliver the antimicrobial agents (doxycycline hyclate, metronidazole and benzyl peroxide) for periodontitis treatment. The gel appearance, pH, viscosity, rheology, syringeability, gel formation, rate of water diffusion into the gels, in vitro degradation, drug release behavior and antimicrobial activities against Staphylococcus aureus, Escherichia coli, Candida albicans, Streptococcus mutans and Porphyrommonas gingivalis were determined. Increasing the amount of EC increased the viscosity of system while still exhibiting Newtonian flow and increased the work of syringeability whereas decreased the releasing of drug. The system transformed into the rigid gel formation after being injected into the simulated gingival crevicular fluid. The developed systems containing 5% w/w antimicrobial agent showed the antimicrobial activities against all test bacteria. Thus the developed solvent exchange-induced in situ forming gels comprising EC-antimicrobial drugs exhibited potential use for periodontitis treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. [Semisynthetic cellulose derivatives as the base of hydrophilic gel systems].

    Science.gov (United States)

    Bajerová, M; Gajdziok, J; Dvorácková, K; Masteiková, R; Kollár, P

    2008-04-01

    The field of drug technology widely ulilizes gel systems of high-molecular substances, which have a number of advantages, such as low toxicity, availability, unique physical properties, biocompatibility, mucoadhesivity, and others. Gel systems are used in the field of local as well as general therapy, in both shape-specific and shape-non-specific dosage forms, in medicaments of the first, second, and third generations. An important group of gels employed in pharmacy are hydrophilic gels or hydrogels, most frequently composed of hydrophilic polymers of natural, semisynthetic and synthetic origin. Though cellulose derivatives as the representatives of polymers of semisynthetic origin are used in pharmaceutical technology for a long time, their research continues and their other possible uses are being searched for. Their advantages include especially safety, easy availability, and a relatively low price. The review paper describes selected cellulose derivatives, their properties and uses in pharmaceutical technology with regard to their use in the field of production of gel systems.

  20. Food gels filled with emulsion droplets : linking large deformation properties to sensory perception

    NARCIS (Netherlands)

    Sala, G.

    2007-01-01

    Key words: polymer gels, particle gels, emulsion, large deformation, friction, sensory This thesis reports studies on the large deformation and lubrication properties of emulsion-filled gels and the way these properties are related to the sensory perception of the gels. The design of the studies

  1. Zirconium molybdate gel as a generator for technetium-99m

    International Nuclear Information System (INIS)

    Evans, J.V.; Shying, M.E.

    1984-12-01

    A new sup(99m)Tc generator based on zirconium molybdate gel is described. Essentially the gel is a cation ion exchanger which permits the elution of the pertechnetate ion. The high molybdenum content of this gel, its stability under self-irradiation, and the absence of organic materials during preparation provide a generator concept that eliminates high processing costs, active waste storage costs and stability problems in other types of generator

  2. Strength of interactions between immobilized dye molecules and sol-gel matrices.

    Science.gov (United States)

    Ismail, Fanya; Schoenleber, Monika; Mansour, Rolan; Bastani, Behnam; Fielden, Peter; Goddard, Nicholas J

    2011-02-21

    In this paper we present a new theory to re-examine the immobilization technique of dye doped sol-gel films, define the strength and types of possible bonds between the immobilized molecule and sol-gel glass, and show that the immobilized molecule is not free inside the pores as was previously thought. Immobilizing three different pH sensitive dyes with different size and functional groups inside the same sol-gel films revealed important information about the nature of the interaction between the doped molecule and the sol-gel matrix. The samples were characterized by means of ultraviolet-visible spectrophotometer (UV-VIS), thermal gravimetric analysis (TGA), mercury porosimetry (MP), nuclear magnetic resonance spectroscopy ((29)Si NMR) and field-emission environmental scanning electron microscopy (ESEM-FEG). It was found that the doped molecule itself has a great effect on the strength and types of the bonds. A number of factors were identified, such as number and types of the functional groups, overall charge, size, pK(a) and number of the silanol groups which surround the immobilized molecule. These results were confirmed by the successful immobilization of bromocresol green (BCG) after a completely polymerized sol-gel was made. The sol-gel consisted of 50% tetraethoxysilane (TEOS) and 50% methyltriethoxysilane (MTEOS) (w/w). Moreover, the effect of the immobilized molecule on the structure of the sol-gel was studied by means of a leaky waveguide (LW) mode for doped films made before and after polymerization of the sol-gel.

  3. Study and application of weak gel used for an offshore oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Tang, X.; Liu, Y.; Bai, B.; Liu, G.; Jiang, R. [Petro-China Research Inst. of Petroleum Exploration and Development, Beijing (China); Xiang, W. [China Offshore Oil Research Center of China National Offshore Oil Co. (China)

    2005-07-01

    This paper described the profile modification technique which has been used successfully in China's oil fields on land and which has become one of the key techniques to improve the development of mature fields with high heterogeneity and high water cut. One such reservoir is SZ361, an offshore oilfield characterized by thick oil layers, high permeability contrast, high oil viscosity and high water salinity. All injection wells were completed by liner gravel-packing. Water cut of some production wells is above 90 per cent. A large volume of weak gel treatment was proposed to control water conformance. A new weak gel was developed to address the specific features of offshore oil fields, such as small space of platform and high salinity of injection water. The gel properties were presented along with an evaluation of the salinity and temperature on the thermal stability of the gel. The plugging efficiency of the gel was carried out on different permeability cores. Results show that the selected polymer and cross-linkers can be well dispersed and solved within 30 minutes when mixing with sea water or produced water. The gelation time can be controlled by adjusting the gel composition. The novel gel can be applied in the reservoirs with a temperature range of 30-70 degrees C and salinity below 40,000 mg/l. The gel was tested in one injection well and proved to be economically efficient. 7 refs., 3 tabs., 8 figs.

  4. Simplified riboprobe purification using translucent straws as gel tubes.

    Science.gov (United States)

    Kol, S; Ben-Shlomo, I; Adashi, E Y; Rohan, R M

    1996-01-01

    Gel purification of radioactive riboprobes enhances the quality of the ribonuclease protection assay. A simple and effective method for riboprobe purification is described. The method uses acrylamide gels in plastic tubes to achieve electrophoretic separation of the RNA polymerase products.

  5. Stronger multilayer acrylic dielectric elastomer actuators with silicone gel coatings

    Science.gov (United States)

    Lau, Gih-Keong; La, Thanh-Giang; Sheng-Wei Foong, Ervin; Shrestha, Milan

    2016-12-01

    Multilayer dielectric elastomer actuators (DEA) perform worst off than single-layer DEAs due to higher susceptibility to electro-thermal breakdown. This paper presents a hot-spot model to predict the electro-thermal breakdown field of DEAs and its dependence on thermal insulation. To inhibit the electrothermal breakdown, silicone gel coating was applied as barrier coating to multilayer acrylic DEA. The gel coating helps suppress the electro-thermally induced puncturing of DEA membrane at the hot spot. As a result, the gel-coated DEAs, in either a single layer or a multilayer stack, can produce 30% more isometric stress change as compared to those none-coated. These gel-coated acrylic DEAs show great potential to make stronger artificial muscles.

  6. Strong poly(ethylene oxide) based gel adhesives via oxime cross-linking.

    Science.gov (United States)

    Ghosh, Smita; Cabral, Jaydee D; Hanton, Lyall R; Moratti, Stephen C

    2016-01-01

    There is a demand for materials to replace or augment the use of sutures and staples in surgical procedures. Currently available commercial surgical adhesives provide either high bond strength with biological toxicity or polymer and protein-based products that are biologically acceptable (though with potential sensitizing potential) but have much reduced bond strength. It is desirable to provide novel biocompatible and biodegradable surgical adhesives/sealants capable of high strength with minimal immune or inflammatory response. In this work, we report the end group derivatization of 8-arm star PEOs with aldehyde and amine end groups. Gels were prepared employing the Schiff-base chemistry between the aldehydes and the amines. Gel setting times, swelling behavior and rheological characterization were carried out for these gels. The mechanical-viscoelastic properties were found to be directly proportional to the crosslinking density of the gels, the 10K PEO gel was stiffer in comparison to the 20K PEO gel. The adhesive properties of these gels were tested using porcine skin and showed excellent adhesion properties. Cytotoxicity studies were carried out for the individual gel components using two different methods: (a) Crystal Violet Staining assay (CVS assay) and (b) impedance and cell index measurement by the xCELLigence system at concentrations >5%. Gels prepared by mixing 20% w/w solutions were also tested for cytotoxicity. The results revealed that the individual gel components as well as the prepared gels and their leachables were non-cytotoxic at these concentrations. This work presents a new type of glue that is aimed at surgery applications using a water soluble star shaped polymer. It show excellent adhesion to skin and is tough and easy to use. We show that it is very biocompatible based on tests on live human cells, and could therefore in principle be used for internal surgery. Comparison with other reported and commercial glues shows that it is stronger

  7. Recent developments in polymer gel dosimetry

    International Nuclear Information System (INIS)

    John Schreiner, L.; Olding, Tim; Holmes, Oliver; McAuley, Kim

    2008-01-01

    Modern radiation therapy particularly with intensity modulation techniques (IMRT) offers the potential to improve patient outcomes by better limiting high doses to the tumour alone. In this presentation we report our progress in developing gel dosimetry with new less toxic dosimeters using a fast commercial optical computed tomography (OCT) scanner. We will demonstrate that these adjustments in the approach to gel dosimetry help facilitate its introduction into clinical use. We will review practical advances in system quality assurance and scatter correction to improve optical CT quantification, and show an example of a clinical implementation of an IGRT treatment validation

  8. Evaluation of a root extract gel from Urtica dioica (Urticaceae) as ...

    African Journals Online (AJOL)

    Purpose: To develop and characterize an herbal gel prepared from methanol root extract of Urtica dioica (Urticaceae) (Stinging nettle) for the treatment of arthritis in mice. Methods: A methanol root extract from Urtica dioica was prepared, and a gel was then prepared using Carbopol 934. The prepared gel was subjected to ...

  9. Rationale, design and methods of the ESPRIT study: Energy, Sexual desire and body PropoRtions wIth AndroGel, Testosterone 1% gel therapy, in hypogonadal men.

    Science.gov (United States)

    Behre, Hermann M; Heinemann, Lothar; Morales, Alvaro; Pexman-Fieth, Claire

    2008-06-01

    Hypogonadism is associated with a range of disease states that have significant effects on morbidity and mortality, and also affect quality of life. The ESPRIT study (Energy, Sexual desire and body PropoRtions wIth AndroGel, Testosterone 1% gel therapy) is a 6-month, multinational, open label, observational study in hypogonadal men being treated with transdermal AndroGel in usual daily clinical practice; 1,700-2,400 patients will be enrolled in Canada, Germany, Central and Eastern Europe, Russia and the Middle East. The main objective will be to evaluate the effect of AndroGel on symptoms of hypogonadism and quality of life as assessed by the Aging Males' Symptoms scale. Further objectives include evaluating the effect and time to onset of improvement in erectile dysfunction and libido/sexual desire (International Index of Erectile Function), fatigue (Multi-dimensional Fatigue Index) and body composition (waist circumference, body mass index). Subgroup analyses will be performed: or = 50 years; absence versus presence of metabolic syndrome. The safety of AndroGel will also be assessed. The study population will consist of newly diagnosed hypogonadal men (age > or = 18 years), in whom testosterone deficiency has been confirmed by clinical features and biochemical tests according to international guidelines, who are currently being prescribed AndroGel (testosterone 1% gel, starting dose 50 mg testosterone per day).

  10. Implementation of nuclear magnetic resonance polymer-gel dosimetry into clinical practice

    International Nuclear Information System (INIS)

    Novotny, Josef Jr.

    2003-01-01

    The aim of this thesis research was to evaluate some basic properties of the polymer-gel dosimeter and test it in clinical practice. Dependence of polymer-gel dosimeter sensitivity on different photon and electron energies as well as on different mean dose rates of standard clinically used linear accelerator was studied. A physical/mathematical description of the effect of temperature on the polymer-gel dosimeter, able to correct a dosimeter 1/T2 response for different temperatures during the NMR measurement, was developed. The polymer-gel dosimeter was tested for the verification of stereotactic radiosurgery techniques with the Leksell Gamma Knife. There was an observed trend in polymer-gel dosimeter sensitivity dependence on quality index for the high-energy x ray beams. Similarly, there was an observed trend in dosimeter sensitivity dependence on mean electron energy. It was demonstrated that these trends were statistically significant. Polymer-gel dosimeter sensitivity was decreased with increased photon or electron energy. There was observed no trend in polymer-gel dosimeter sensitivity dependence on mean dose rates for both photon and electron beams within experimental errors. It was demonstrated in this study that the NMR 1/T2-dose response is increased for lower temperatures of the evaluated polymer-gel samples. The relaxation rate response can be expressed as a function consisting of two terms, one denoted for the temperature dependence and the other one for the dose dependence. Two clinical applications of the polymer-gel dosimeter were demonstrated in this study. The first experiment allowed a check of the entire stereotactic procedure with the Leksell gamma knife including target stereotactic localization on NMR, treatment planning, and irradiation. The second experiment evaluated dosimetric and geometric inaccuracies associated with the stereotactic irradiation of the experimental rat brain. It was demonstrated that polymer-gel can be effectively used

  11. Allopurinol gel mitigates radiation-induced mucositis and dermatitis

    International Nuclear Information System (INIS)

    Kitagawa, Junichi; Nasu, Masanori; Okumura, Hayato; Matsumoto, Shigeji; Shibata, Akihiko; Makino, Kimiko; Terada, Hiroshi

    2008-01-01

    It has not been verified whether allopurinol application is beneficial in decreasing the severity of radiation-induced oral mucositis and dermatitis. Rats were divided into 4 groups and received 15 Gy irradiation on the left whisker pad. Group 1 received only irradiation. Group 2 was maintained by applying allopurinol/carrageenan-mixed gel (allopurinol gel) continuously from 2 days before to 20 days after irradiation. Group 3 had allopurinol gel applied for 20 days after radiation. Group 4 was maintained by applying carrageenan gel continuously from 2 days before to 20 days after irradiation. The intra oral mucosal and acute skin reactions were assessed daily using mucositis and skin score systems. The escape thresholds for mechanical stimulation to the left whisker pad were measured daily. In addition, the irradiated tissues at the endpoint of this study were compared with naive tissue. Escape threshold in group 2 was significantly higher than that in group 1, and mucositis and skin scores were much improved compared with those of group 1. Concerning escape threshold, mucositis and skin scores in group 3 began to improve 10 days after irradiation. Group 4 showed severe symptoms of mucositis and dermatitis to the same extent as that observed in group 1. In the histopathological study, the tissues of group 1 showed severe inflammatory reactions, compared with those of group 2. These results suggest that allopurinol gel application can mitigate inflammation reactions associated with radiation-induced oral mucositis and dermatitis. (author)

  12. Dextrose gel treatment does not impair subsequent feeding.

    Science.gov (United States)

    Weston, Philip J; Harris, Deborah L; Harding, Jane E

    2017-11-01

    Dextrose gel is increasingly used as first-line treatment for neonatal hypoglycaemia. Treatment with 400 mg/kg previously has been reported to impair subsequent feeding. We sought to determine if the recommended dose of 200 mg/kg altered feeding. Hypoglycaemic babies were randomised to 200 mg/kg dextrose gel or placebo and fed. Prefeed alertness, quality and duration of breast feeding, and the volume of formula taken were assessed on the next feeding. Prefeed alertness scores were similar in babies (n=211) treated with dextrose or placebo gel (124 episodes, OR=1.30 (95% CI 0.62 to 2.77), p=0.49). Breastfed babies were more likely to have good feeding scores after dextrose gel (160 episodes, OR=3.54 (95% CI 1.30 to 9.67), p=0.01) but similar breastfeeding duration (57 episodes, median (range) 20 (3-90) vs 25 (2-80) min, p=0.62). Formula volumes taken were also similar (24 episodes, median (range) 4.6 (2.2-11.3) vs 6.4 (2.0-8.9) mL/kg, p=0.30). Treating hypoglycaemic babies with dextrose gel 200 mg/kg does not depress subsequent feeding and may improve breastfeeding quality. ACTRN 12608000623392. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Hyper alginate gel microbead formation by molecular diffusion at the hydrogel/droplet interface.

    Science.gov (United States)

    Hirama, Hirotada; Kambe, Taisuke; Aketagawa, Kyouhei; Ota, Taku; Moriguchi, Hiroyuki; Torii, Toru

    2013-01-15

    We report a simple method for forming monodispersed, uniformly shaped gel microbeads with precisely controlled sizes. The basis of our method is the placement of monodispersed sodium alginate droplets, formed by a microfluidic device, on an agarose slab gel containing a high-osmotic-pressure gelation agent (CaCl(2) aq.): (1) the droplets are cross-linked (gelated) due to the diffusion of the gelation agent from the agarose slab gel to the sodium alginate droplets and (2) the droplets simultaneously shrink to a fraction of their original size (slab gel. We verified the mass transfer mechanism between the droplet and the agarose slab gel. This method circumvents the limitations of gel microbead formation, such as the need to prepare microchannels of various sizes, microchannel clogging, and the deformation of the produced gel microbeads.

  14. Growth and study of some gel grown group II single crystals of iodate

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Single crystals of calcium iodate and barium iodate were grown by simple gel technique by single diffusion method. The optimum conditions were established by varying various parameters such as pH of gel solution, gel concentration, gel setting time, concentration of the reactants etc. Crystals having different.

  15. Evaluation of Topical Gel Bases Formulated with Various Essential ...

    African Journals Online (AJOL)

    Evaluation of Topical Gel Bases Formulated with Various Essential Oils for Antibacterial Activity against Methicillin- Resistant Staphylococcus Aureus. ... Lemon grass and thyme oils were chosen for further studies, including analysis of their composition by gas chromatography–mass spectrometry (GC/MS). Gels were ...

  16. Gel Dosimetry Analysis of Gold Nanoparticle Application in Kilovoltage Radiation Therapy

    International Nuclear Information System (INIS)

    Marques, T; Schwarcke, M; Garrido, C; Zucolot, V; Baffa, O; Nicolucci, P

    2010-01-01

    In this work gold nanoparticles (AuNP) were embedded in MAGIC-f gel and irradiated in a 250 kV x-ray clinical beam. The signal of non-irradiated gel samples containing AuNPs showed maximum difference of 0.5% related to gel without nanoparticles. Different AuNPs concentrations were studied: 0.10 mM, 0.05 mM and 0.02 mM, presenting dose enhancements of 106%, 90% and 77% respectively. Monte Carlo spectrometry was performed to quantify theoretical changes in photon energy spectrums due to AuNPs presence. Concordance between simulated dose enhancements and gel dosimetry measurements was better than 97% to all concentrations studied. This study evidences that polymer gel dosimetry as a suitable tool to perform dosimetric investigations of nanoparticle applications in Radiation Therapy.

  17. Thixotropic gel-like composition and sterile blood-collecting and separating device

    International Nuclear Information System (INIS)

    Semersky, F.E.

    1980-01-01

    A thixotropic gel-like composition comprising liquid polybutadiene and an inorganic inert filler dispersed therein is adapted for use as a sealing barrier between separated phases of differing densities of a fluid in which said composition has at rest a density intermediate said differing densities, said gel-like composition being substantially resistant to sterilizing radiation. There is also disclosed a pre-packaged blood collecting and separating device which contains a mixture of liquid polybutadiene and an inorganic, inert filler, such as silica, as a thixotropic gel adapted at rest to form a sealing barrier between separated blood phases. The device and gel are subjected to sterilizing radiation to form a substantially sterile device, substantially free of backflow contamination without degradation of the physical properties of the gel. (author)

  18. Use of Magic polymer gels for dosimetry of unsealed source of yttrium 90

    International Nuclear Information System (INIS)

    Meynard, K.; Bordage, M.C.; Cassol, E.; Courbon, F.; Ravel, P.

    2007-01-01

    Polymer gels are relative chemical dosimeters. They allow to access to three-dimensional dose distribution. The aim of this study has been to investigate the preparation and the use of a polymer gel with a tissue equivalent density known as MAGIC gel from magnetic resonance imaging and x-ray computed tomography for non-sealed source dosimetry. This kind of gel is 'normoxic' because it can be manufactured and used in normal room atmosphere. In the first part of this study, its accuracy and sensibility were studied using external beam irradiation by photons. Spin-spin relaxation rate (R 2 ) and Computed Tomography (CT) number had been used to record gel responses. Using the same manufacture process. radiolabelled gels composed of 95% MAGIC gel and 5% of 90 Y termed 90 Y-MAGIC 95 with varying activity ranged from 0 to 30 MBq were made. In case of photon external beam irradiation, a linear response is observed whatever the calibration method and the imaging system used (the correlation coefficient r 2 > 0.98 in all cases). 90 Y-MAGIC 95 radiolabelled gel responses were recorded after 28. 76 and 124 h. The R 2 /dose curves are not linear: three phases can be described. the first being linear with a slow slope (0.14 s -1 Gy -1 instead of 0.41 s -1 Gy -1 for external beam irradiation of the same gel batch). This study shows safety of radiolabelled MAGIC gels manufacturing process and their large dosimetric feasibility. 90 Y-MAGIC 95 gel response appears to be reproducible and related to the absorbed dose, thus this gel is a promising tool for non-sealed source dosimetry. (authors)

  19. Superconductive ceramics obtained with sol gel method

    International Nuclear Information System (INIS)

    Arcangeli, A.; Mosci, A.; Nardi, A.; Vatteroni, R.; Zondini, C.

    1988-01-01

    Several sol gel routes have been considered, studied and developed to produce large quantities of granulates which can be processed to obtain ceramics having good superconducting characteristics. In the considered process a mixture of commercial nitrates is atomized, at room temperature, in a solution 1:1 of Primene JMT and Benzene and a pale blue gel of the starting elements is suddently formed. The granulates obtained are free flowing, very reactive and well suited for pressing. For their intrinsic characteristics they could be very good precursors for the production of large quantities of superconductive ceramics in different forms. The precipitated gel is dried, calcinated, pressed in the form of cylindrical pellets which are sintered up to 960 degrees C. No griding or different thermal treatments are needed. The sintered material has low electric resistence, shows a clear Meissner effect and has a transition temperature of between 91 and 95 K

  20. Manufacture of Regularly Shaped Sol-Gel Pellets

    Science.gov (United States)

    Leventis, Nicholas; Johnston, James C.; Kinder, James D.

    2006-01-01

    An extrusion batch process for manufacturing regularly shaped sol-gel pellets has been devised as an improved alternative to a spray process that yields irregularly shaped pellets. The aspect ratio of regularly shaped pellets can be controlled more easily, while regularly shaped pellets pack more efficiently. In the extrusion process, a wet gel is pushed out of a mold and chopped repetitively into short, cylindrical pieces as it emerges from the mold. The pieces are collected and can be either (1) dried at ambient pressure to xerogel, (2) solvent exchanged and dried under ambient pressure to ambigels, or (3) supercritically dried to aerogel. Advantageously, the extruded pellets can be dropped directly in a cross-linking bath, where they develop a conformal polymer coating around the skeletal framework of the wet gel via reaction with the cross linker. These pellets can be dried to mechanically robust X-Aerogel.

  1. Ultraviolet absorption detection of DNA in gels

    International Nuclear Information System (INIS)

    Mahon, A.R.

    1998-01-01

    A method and apparatus for the detection and quantification of large fragments of unlabelled deoxyribonucleic acid (DNA) in agarose gels is presented. The technique is based on ultra-violet (UV) absorption by nucleotides. A deuterium lamp was used to illuminate regions of an electrophoresis gel. As DNA bands passed through the illuminated region of the gel the amount of UV light transmitted was reduced due to DNA absorption. Two detection systems were investigated. In the first system, synthetic chemical vapour deposition (CVD) diamond strip detectors were used to locate regions of DNA in the gels by detecting the transmitted light. CVD diamond has a high indirect band gap of 5.45 eV and is therefore sensitive to UV photons of wavelengths < 224 nm. A number of CVD diamond samples were characterised to investigate their suitability as detectors for this application. The detectors' quantum efficiency, UV response and time response were measured. DNA bands containing as little as 20 ng were detected by the diamond. In a second system, a deuterium lamp was used to illuminate individual sample lanes of an electrophoresis gel via an array of optical fibres. During electrophoresis the regions of DNA were detected with illumination at 260 nm, using a UV-sensitive charge coupled device (CCD). As the absorption coefficient of a DNA sample is approximately proportional to its mass, the technique is inherently quantitative. This system had a detection limit of 0.25 ng compared with 2-10 ng for the most popular conventional technique, ethidium bromide (EtBr) staining. Using this detection technique, the DNA sample remains in its native state. The removal of carcinogenic dyes from the detection procedure greatly reduces associated biological hazards. (author)

  2. Diffusion measurement in ferrous infused gel dosimeters

    International Nuclear Information System (INIS)

    Zahmatkesh, M. H.; Healy, B. J.

    2003-01-01

    Background: The compositions of Ferrous sulphate, Agarose and Xylenol orange dye and Ferrous sulphate, Gelatin and Xylenol orange dye in solution of distilled water and sulphuric acid are two tissue-equivalent gel dosimeters. Ionizing radiation causes oxidation of Fe 2+ ion to Fe 3+ ions which diffuse through the gel matrix and blur the image of absorbed dose over a period of hours after irradiation. Materials and methods: 25 m M sulphuric acid, 0.4 mm ferrous ammonium sulphate, 0.2 mm xylenol orange dye and 1% by weight agarose in distilled water named Agarose and Xylenol orange dye and 0.1 mm ferrous ammonium sulphate, 0.1 mm xylenol orange dye, 50 mm sulphuric acid and 5% by weight gelatin in distilled water named Gelatin and Xylenol orange dye are used as two gel dosimeters. All chemicals were supplied by Sigma Ald ridge Company, Germany. The gels were poured in Perspex casts and were irradiated to a beam of X ray from linear accelerators or X ray machine. Results: In this study diffusion coefficients of Agarose and Xylenol orange dye and Gelatin and Xylenol orange dye dosimeters have been measured through a computer program for different temperature. The ferric ion diffusion coefficient (D) for the Agarose and Xylenol orange dye and Gelatin and Xylenol orange dye dosimeters were measured as (1.19.±0.03) x 10 -2 cm 2 .hr -1 and (0.83±0.03) x 10 -2 cm 2 .hr -1 respectively at room temperature. Conclusion: For both dosimeters the diffusion coefficients decreased with gel storage temperatures down to 6 d ig C . Gelatin and Xylenol orange dye dosimeters have advantage of lower diffusion coefficient for a specified temperature

  3. Automatic and quantitative measurement of collagen gel contraction using model-guided segmentation

    Science.gov (United States)

    Chen, Hsin-Chen; Yang, Tai-Hua; Thoreson, Andrew R.; Zhao, Chunfeng; Amadio, Peter C.; Sun, Yung-Nien; Su, Fong-Chin; An, Kai-Nan

    2013-08-01

    Quantitative measurement of collagen gel contraction plays a critical role in the field of tissue engineering because it provides spatial-temporal assessment (e.g., changes of gel area and diameter during the contraction process) reflecting the cell behavior and tissue material properties. So far the assessment of collagen gels relies on manual segmentation, which is time-consuming and suffers from serious intra- and inter-observer variability. In this study, we propose an automatic method combining various image processing techniques to resolve these problems. The proposed method first detects the maximal feasible contraction range of circular references (e.g., culture dish) and avoids the interference of irrelevant objects in the given image. Then, a three-step color conversion strategy is applied to normalize and enhance the contrast between the gel and background. We subsequently introduce a deformable circular model which utilizes regional intensity contrast and circular shape constraint to locate the gel boundary. An adaptive weighting scheme was employed to coordinate the model behavior, so that the proposed system can overcome variations of gel boundary appearances at different contraction stages. Two measurements of collagen gels (i.e., area and diameter) can readily be obtained based on the segmentation results. Experimental results, including 120 gel images for accuracy validation, showed high agreement between the proposed method and manual segmentation with an average dice similarity coefficient larger than 0.95. The results also demonstrated obvious improvement in gel contours obtained by the proposed method over two popular, generic segmentation methods.

  4. Optical Sensors for Biomolecules Using Nanoporous Sol-Gel Materials

    Science.gov (United States)

    Fang, Jonathan; Zhou, Jing C.; Lan, Esther H.; Dunn, Bruce; Gillman, Patricia L.; Smith, Scott M.

    2004-01-01

    An important consideration for space missions to Mars is the ability to detect biosignatures. Solid-state sensing elements for optical detection of biological entities are possible using sol-gel based biologically active materials. We have used these materials as optical sensing elements in a variety of bioassays, including immunoassays and enzyme assays. By immobilizing an appropriate biomolecule in the sol-gel sensing element, we have successfully detected analytes such as amino acids and hormones. In the case of the amino acid glutamate, the enzyme glutamate dehydrogenase was the immobilized molecule, whereas in the case of the hormone cortisol, an anti-cortisol antibody was immobilized in the sensing element. In this previous work with immobilized enzymes and antibodies, excellent sensitivity and specificity were demonstrated in a variety of formats including bulk materials, thin films and fibers. We believe that the sol-gel approach is an attractive platform for bioastronautics sensing applications because of the ability to detect a wide range of entities such as amino acids, fatty acids, hopanes, porphyrins, etc. The sol-gel approach produces an optically transparent 3D silica matrix that forms around the biomolecule of interest, thus stabilizing its structure and functionality while allowing for optical detection. This encapsulation process protects the biomolecule and leads to a more "rugged" sensor. The nanoporous structure of the sol-gel matrix allows diffusion of small target molecules but keeps larger, biomolecules immobilized in the pores. We are currently developing these biologically active sol-gel materials into small portable devices for on-orbit cortisol detection

  5. Environmentally benign sol-gel antifouling and foul-releasing coatings.

    Science.gov (United States)

    Detty, Michael R; Ciriminna, Rosaria; Bright, Frank V; Pagliaro, Mario

    2014-02-18

    Biofouling on ships and boats, characterized by aquatic bacteria and small organisms attaching to the hull, is an important global issue, since over 80000 tons of antifouling paint is used annually. This biofilm, which can form in as little as 48 hours depending on water temperature, increases drag on watercraft, which greatly reduces their fuel efficiency. In addition, biofouling can lead to microbially induced corrosion (MIC) due to H2S formed by the bacteria, especially sulfate-reducing bacteria. When the International Maritime Organization (IMO) international convention banned the use of effective but environmentally damaging coatings containing tributyl tin in 2008, the development of clean and effective antifouling systems became more important than ever. New nonbiocidal coatings are now in high demand. Scientists have developed new polymers, materials, and biocides, including new elastomeric coatings that they have obtained by improving the original silicone (polydimethylsiloxane) formulation patented in 1975. However, the high cost of silicones, especially of fluoropolymer-modified silicones, has generally prevented their large-scale diffusion. In 2009, traditional antifouling coatings using cuprous oxide formulated in copolymer paints still represented 95% of the global market volume of anti-fouling paints. The sol-gel nanochemistry approach to functional materials has emerged as an attractive candidate for creating low fouling surfaces due to the unique structure and properties of silica-based coatings and of hybrid inorganic-organic silicas in particular. Sol-gel formulations easily bind to all types of surfaces, such as steel, fiberglass, aluminum, and wood. In addition, they can cure at room temperature and form thin glassy coatings that are markedly different from thick silicone elastomeric foul-releasing coatings. Good to excellent performance against biofouling, low cure temperatures, enhanced and prolonged chemical and physical stability, ease of

  6. PENGARUH ASAM AKROBAT TERHADAP PEMBENTUKAN GEL MIOFIBRIL IKAN MATA BESAR (Selar crumenophthalnus [effect of ascorbic acid on gel formation of myofibril from big eye scad fish (Selar crumenophthalnus

    Directory of Open Access Journals (Sweden)

    Yuli Witono

    2005-08-01

    Full Text Available Effect of ascorbic acid on gel formation of myofibril from big eye scad fish (Selar crumenophthalnuswere studied for its development as food ingredient. Myofibril was galled by the addition of various concentrations of ascorbic acid (0, 0.1, 0.2, 0.3 and 0.4% and the gels were then characterized for its cooking loss, of the gel, but at 0.4% the cooking loss of gel increased significantly. Accordingly, the WHC of the gel changed insignificantly with the ascorbic acid addition below 0.3%, and decrease sharply in the addition of 0.4%. Gel textures were affected by the addition of ascorbic acid at all levels, namely 29.9 ± 1.9, 31.0 ± 0.3, 35.4 ± 0.4, 46.7 ± 1.5, and 115.7 ± 3.2 g/7 mm for 0, 0.1, 0.2, 0.3 and 0.4%, respectively. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE showed that addition of ascorbic acid drove formation odfdisulphide bond in the myosin heavy chain (MHC and other myofirillar proteins, resulting in the development of a strong three dimensions structure I myofibril gel as shown by microscopic structure.

  7. Three dimensional gel dosimetry by use of nuclear magnetic resonance imaging (MRI)

    Energy Technology Data Exchange (ETDEWEB)

    De Deene, Y; De Wagter, C; Van Duyse, B; Achten, E; De Neve, W [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde; De Poorter, J [Ghent Univ. (Belgium). Dept. of Magnetic Resonance

    1995-12-01

    As co-monomers are found to polymerize by radiation, they are eligible for constructing a three dimensional dosimeter. Another kind of three dimensional dosimeter, based on the radiation sensitivity of the ferrous ions in a Fricke solution, was tested in a previous study. However, a major problem that occurs in this kind of gel dosimeters is the diffusion of the ferric and ferrous ions. The co-monomer gels are more stable. The degree of polymerisation is visualized with a clinical MRI system. Acrylamide and N,N-methylene-bis-acrylamide are dissolved in a gel composed of gelatin and water. By irradiation the co-monomers are polymerized to polyacrylamide. The gel is casted in humanoid forms. As such, a simulation of the irradiation of the patient can be performed. Magnetic resonance relaxivity images of the irradiated gel display the irradiation dose. The images of the gel are fused with the radiological images of the patient. Quantitation of the dose response of the co-monomer gel is obtained through calibration by test tubes.

  8. Three dimensional gel dosimetry by use of nuclear magnetic resonance imaging (MRI)

    International Nuclear Information System (INIS)

    De Deene, Y.; De Wagter, C.; Van Duyse, B.; Achten, E.; De Neve, W.; De Poorter, J.

    1995-01-01

    As co-monomers are found to polymerize by radiation, they are eligible for constructing a three dimensional dosimeter. Another kind of three dimensional dosimeter, based on the radiation sensitivity of the ferrous ions in a Fricke solution, was tested in a previous study. However, a major problem that occurs in this kind of gel dosimeters is the diffusion of the ferric and ferrous ions. The co-monomer gels are more stable. The degree of polymerisation is visualized with a clinical MRI system. Acrylamide and N,N-methylene-bis-acrylamide are dissolved in a gel composed of gelatin and water. By irradiation the co-monomers are polymerized to polyacrylamide. The gel is casted in humanoid forms. As such, a simulation of the irradiation of the patient can be performed. Magnetic resonance relaxivity images of the irradiated gel display the irradiation dose. The images of the gel are fused with the radiological images of the patient. Quantitation of the dose response of the co-monomer gel is obtained through calibration by test tubes

  9. Quality change of apple slices coated with Aloe vera gel during storage.

    Science.gov (United States)

    Song, Hye-Yeon; Jo, Wan-Shin; Song, Nak-Bum; Min, Sea C; Song, Kyung Bin

    2013-06-01

    Fresh-cut apples are easily susceptible to browning and microbial spoilage. In this study, an edible coating prepared from Aloe vera gel containing antibrowning solution was applied to preserve the quality of fresh-cut apples during storage. Fresh-cut apples were treated with both an Aloe vera gel and an Aloe vera gel containing 0.5% cysteine and then stored at 4 °C for 16 d. The color, firmness, weight loss, soluble solid content, titratable acidity, microbial analysis, and sensory evaluation were analyzed during storage. Fresh-cut apples coated with the Aloe vera gel showed delayed browning and reduced weight loss and softening compared to the control. The Aloe vera gel coating was also effective in reducing the populations of the total aerobic bacteria and yeast and molds. In particular, Aloe vera gel containing 0.5% cysteine was most effective in delaying browning and the reduction of microbial populations among the treatments. These results suggest that an Aloe vera gel coating can be used for maintaining the quality of fresh-cut apples. © 2013 Institute of Food Technologists®

  10. An evaluation of 10 percent and 20 percent benzocaine gels in patients with acute toothaches

    Science.gov (United States)

    Hersh, Elliot V.; Ciancio, Sebastian G.; Kuperstein, Arthur S.; Stoopler, Eric T.; Moore, Paul A.; Boynes, Sean G.; Levine, Steven C.; Casamassimo, Paul; Leyva, Rina; Mathew, Tanya; Shibly, Othman; Creighton, Paul; Jeffers, Gary E.; Corby, Patricia M.A.; Turetzky, Stanley N.; Papas, Athena; Wallen, Jillian; Idzik-Starr, Cynthia; Gordon, Sharon M.

    2013-01-01

    Background The authors evaluated the efficacy and tolerability of 10 percent and 20 percent benzocaine gels compared with those of a vehicle (placebo) gel for the temporary relief of toothache pain. They also assessed the compliance with the label dose administration directions on the part of participants with toothache pain. Methods Under double-masked conditions, 576 participants self-applied study gel to an open tooth cavity and surrounding oral tissues. Participants evaluated their pain intensity and pain relief for 120 minutes. The authors determined the amount of gel the participants applied. Results The responders’ rates (the primary efficacy parameter), defined as the percentage of participants who had an improvement in pain intensity as exhibited by a pain score reduction of at least one unit on the dental pain scale from baseline for two consecutive assessments any time between the five- and 20-minute points, were 87.3 percent, 80.7 percent and 70.4 percent, respectively, for 20 percent benzocaine gel, 10 percent benzocaine gel and vehicle gel. Both benzocaine gels were significantly (P ≤ .05) better than vehicle gel; the 20 percent benzocaine gel also was significantly (P ≤ .05) better than the 10 percent benzocaine gel. The mean amount of gel applied was 235.6 milligrams, with 88.2 percent of participants applying 400 mg or less. Conclusions Both 10 percent and 20 percent benzocaine gels were more efficacious than the vehicle gel, and the 20 percent benzocaine gel was more efficacious than the 10 percent benzocaine gel. All treatments were well tolerated by participants. Practical Implications Patients can use 10 percent and 20 percent benzocaine gels to temporarily treat toothache pain safely. PMID:23633700

  11. Comparative antimicrobial activities of aloe vera gel and leaf ...

    African Journals Online (AJOL)

    The comparative antimicrobial activities of the gel and leaf of Aloe vera were tested against Staphylococcus aureus, Pseudomonas aeruginosa, Trichophyton mentagraphytes, T. schoeleinii, Microsporium canis and Candida albicans. Ethanol was used for the extraction of the leaf after obtaining the gel from it. Antimicrobial ...

  12. Hybrid carrageenans: isolation, chemical structure, and gel properties.

    Science.gov (United States)

    Hilliou, Loic

    2014-01-01

    Hybrid carrageenan is a special class of carrageenan with niche application in food industry. This polysaccharide is extracted from specific species of seaweeds belonging to the Gigartinales order. This chapter focuses on hybrid carrageenan showing the ability to form gels in water, which is known in the food industry as weak kappa or kappa-2 carrageenan. After introducing the general chemical structure defining hybrid carrageenan, the isolation of the polysaccharide will be discussed focusing on the interplay between seaweed species, extraction parameters, and the hybrid carrageenan chemistry. Then, the rheological experiments used to determine the small and large deformation behavior of gels will be detailed before reviewing the relationships between gel properties and hybrid carrageenan chemistry. © 2014 Elsevier Inc. All rights reserved.

  13. Ultrastructure and growth factor content of equine platelet-rich fibrin gels.

    Science.gov (United States)

    Textor, Jamie A; Murphy, Kaitlin C; Leach, J Kent; Tablin, Fern

    2014-04-01

    To compare fiber diameter, pore area, compressive stiffness, gelation properties, and selected growth factor content of platelet-rich fibrin gels (PRFGs) and conventional fibrin gels (FGs). PRFGs and conventional FGs prepared from the blood of 10 healthy horses. Autologous fibrinogen was used to form conventional FGs. The PRFGs were formed from autologous platelet-rich plasma of various platelet concentrations (100 × 10³ platelets/μL, 250 × 10³ platelets/μL, 500 × 10³ platelets/μL, and 1,000 × 10³ platelets/μL). All gels contained an identical fibrinogen concentration (20 mg/mL). Fiber diameter and pore area were evaluated with scanning electron microscopy. Maximum gelation rate was assessed with spectrophotometry, and gel stiffness was determined by measuring the compressive modulus. Gel weights were measured serially over 14 days as an index of contraction (volume loss). Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were quantified with ELISAs. Fiber diameters were significantly larger and mean pore areas were significantly smaller in PRFGs than in conventional FGs. Gel weight decreased significantly over time, differed significantly between PRFGs and conventional FGs, and was significantly correlated with platelet concentration. Platelet-derived growth factor-BB and transforming growth factor-β1 concentrations were highest in gels and releasates derived from 1,000 × 10³ platelets/μL. The inclusion of platelets in FGs altered the architecture and increased the growth factor content of the resulting scaffold. Platelets may represent a useful means of modifying these gels for applications in veterinary and human regenerative medicine.

  14. Oral dextrose gel for the treatment of hypoglycaemia in newborn infants.

    Science.gov (United States)

    Weston, Philip J; Harris, Deborah L; Battin, Malcolm; Brown, Julie; Hegarty, Joanne E; Harding, Jane E

    2016-05-04

    Neonatal hypoglycaemia, a common condition, can be associated with brain injury. It is frequently managed by providing infants with an alternative source of glucose, given enterally with formula or intravenously with dextrose solution. This often requires that mother and baby are cared for in separate environments and may inhibit breast feeding. Dextrose gel is simple and inexpensive and can be administered directly to the buccal mucosa for rapid correction of hypoglycaemia, in association with continued breast feeding and maternal care. To assess the effectiveness of dextrose gel in correcting hypoglycaemia and in reducing long-term neurodevelopmental impairment. We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Web of Science from inception of the database to February 2016. We also searched international clinical trials networks and handsearched proceedings of specific scientific meetings. Randomised and quasi-randomised studies comparing dextrose gel versus placebo, no treatment or other therapies for treatment of neonatal hypoglycaemia. Two review authors independently assessed trial quality and extracted data and did not assess publications for which they themselves were study authors. We included two trials involving 312 infants. No data were available for correction of hypoglycaemia for each hypoglycaemic event. We found no evidence of a difference between dextrose gel and placebo gel for major neurosensory disability at two-year follow-up (risk ratio (RR) 6.27, 95% confidence interval (CI) 0.77 to 51.03; one trial, n = 184; quality of evidence very low). Dextrose gel compared with placebo gel or no gel did not alter the need for intravenous treatment for hypoglycaemia (typical RR 0.78, 95% CI 0.46 to 1.32; two trials, 312 infants; quality of evidence very low). Infants treated with dextrose gel were less likely to be separated from their

  15. Comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain and aloe vera (all in gel formulation), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis: An in vitro study.

    Science.gov (United States)

    Bhardwaj, Anuj; Ballal, Suma; Velmurugan, Natanasabapathy

    2012-07-01

    A comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain, and aloe vera (all in gel formulations), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis-an in vitro study. The antimicrobial efficacy was assessed in vitro using dentin shavings collected at 2 depths of 200 and 400 μm. The total colony forming units at the end of 1, 3, and 5 days were assessed. The overall percentage inhibition of bacterial growth (200 and 400 μm depth) was 100% with chlorhexidine gel. This was followed by M. citrifolia gel (86.02%), which showed better antimicrobial efficacy as compared with aloe vera gel (78.9%), papain gel (67.3%), and calcium hydroxide (64.3%). There was no statistical difference between data at 200 and 400 μm depth. Chlorhexidine gel showed the maximum antimicrobial activity against E. faecalis, whereas calcium hydroxide showed the least. Among the natural intracanal medicaments, M. citrifolia gel consistently exhibited good inhibition up to the 5(th) day followed by aloe vera gel and papain gel.

  16. Cell-Based Fabrication of Organic/Inorganic Composite Gel Material

    Directory of Open Access Journals (Sweden)

    Takayoshi Nakano

    2011-01-01

    Full Text Available Biomaterials containing components similar to the native biological tissue would have benefits as an implantable scaffold material. To obtain such biomimetic materials, cells may be great contributors because of their crucial roles in synthetic organics. In addition, the synthesized organics—especially those derived from osteogenic differentiated cells—become a place where mineral crystals nucleate and grow even in vitro. Therefore to fabricate an organic/inorganic composite material, which is similar to the biological osteoid tissue, bone marrow derived mesenchymal stem cells (BMSCs were cultured in a 3D fibrin gel in this study. BMSCs secreted bone-related proteins that enhanced the biomineralization within the gel when the cells were cultured with an osteogenic differentiation medium. The compositions of both synthesized matrices and precipitated minerals in the obtained materials altered depending on the cell culture period. The mineral obtained in the 3D gel showed low crystalline hydroxyapatite. The composite materials also showed excellent osteoconductivity with new bone formation when implanted in mice tibiae. Thus, we demonstrated the contributions of cells for fabricating implantable organic/inorganic composite gel materials and a method for controlling the material composition in the gel. This cell-based material fabrication method would be a novel method to fabricate organic/inorganic composite biomimetic materials for bone tissue engineering.

  17. A New Combination of Testosterone and Nestorone Transdermal Gels for Male Hormonal Contraception

    Science.gov (United States)

    Ilani, Niloufar; Roth, Mara Y.; Amory, John K.; Swerdloff, Ronald S.; Dart, Clint; Page, Stephanie T.; Bremner, William J.; Sitruk-Ware, Regine; Kumar, Narender; Blithe, Diana L.

    2012-01-01

    Context: Combinations of testosterone (T) and nestorone (NES; a nonandrogenic progestin) transdermal gels may suppress spermatogenesis and prove appealing to men for contraception. Objective: The objective of the study was to determine the effectiveness of T gel alone or combined with NES gel in suppressing spermatogenesis. Design and Setting: This was a randomized, double-blind, comparator clinical trial conducted at two academic medical centers. Participants: Ninety-nine healthy male volunteers participated in the study. Interventions: Volunteers were randomized to one of three treatment groups applying daily transdermal gels (group 1: T gel 10 g + NES 0 mg/placebo gel; group 2: T gel 10 g + NES gel 8 mg; group 3: T gel 10 g + NES gel 12 mg). Main Outcome Variable: The main outcome variable of the study was the percentage of men whose sperm concentration was suppressed to 1 million/ml or less by 20–24 wk of treatment. Results: Efficacy data analyses were performed on 56 subjects who adhered to the protocol and completed at least 20 wk of treatment. The percentage of men whose sperm concentration was 1 million/ml or less was significantly higher for T + NES 8 mg (89%, P male range throughout the treatment period. Adverse effects were minimal in all groups. Conclusion: A combination of daily NES + T gels suppressed sperm concentration to 1 million/ml or less in 88.5% of men, with minimal adverse effects, and may be further studied as a male transdermal hormonal contraceptive. PMID:22791756

  18. Increased Y-chromosome resolution of haplogroup O suggests genetic ties between the Ami aborigines of Taiwan and the Polynesian Islands of Samoa and Tonga.

    Science.gov (United States)

    Mirabal, Sheyla; Herrera, Kristian J; Gayden, Tenzin; Regueiro, Maria; Underhill, Peter A; Garcia-Bertrand, Ralph L; Herrera, Rene J

    2012-01-25

    The Austronesian expansion has left its fingerprint throughout two thirds of the circumference of the globe reaching the island of Madagascar in East Africa to the west and Easter Island, off the coast of Chile, to the east. To date, several theories exist to explain the current genetic distribution of Austronesian populations, with the "slow boat" model being the most widely accepted, though other conjectures (i.e., the "express train" and "entangled bank" hypotheses) have also been widely discussed. In the current study, 158 Y chromosomes from the Polynesian archipelagos of Samoa and Tonga were typed using high resolution binary markers and compared to populations across Mainland East Asia, Taiwan, Island Southeast Asia, Melanesia and Polynesia in order to establish their patrilineal genetic relationships. Y-STR haplotypes on the C2 (M38), C2a (M208), O1a (M119), O3 (M122) and O3a2 (P201) backgrounds were utilized in an attempt to identify the differing sources of the current Y-chromosomal haplogroups present throughout Polynesia (of Melanesian and/or Asian descent). We find that, while haplogroups C2a, S and K3-P79 suggest a Melanesian component in 23%-42% of the Samoan and Tongan Y chromosomes, the majority of the paternal Polynesian gene pool exhibits ties to East Asia. In particular, the prominence of sub-haplogroup O3a2c* (P164), which has previously been observed at only minimal levels in Mainland East Asians (2.0-4.5%), in both Polynesians (ranging from 19% in Manua to 54% in Tonga) and Ami aborigines from Taiwan (37%) provides, for the first time, evidence for a genetic connection between the Polynesian populations and the Ami. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Effect of saccharide additives on response of ferrous-agarose-xylenol orange radiotherapy gel dosimeters

    International Nuclear Information System (INIS)

    Healy, B.J.; Zahmatkesh, M.H.; Nitschke, K.N.; Baldock, C.

    2003-01-01

    Glucose, sucrose, starch, and locust bean gum have been used as additives to the ferrous-agarose-xylenol orange (FAX) gel dosimeter. The saccharide enhanced dosimeters were found to have a higher dose sensitivity over a standard FAX gel as measured by both optical density change and magnetic resonance imaging (MRI). With optical density measurement, OD-dose sensitivity increases were up to 55% for glucose, 122% for sucrose and 43% for starch, while locust bean gum did not give a consistent response. With MRI, R 1 -dose sensitivity increases were up to 178% with sucrose addition. The FAX gel with sucrose was studied in greatest detail. The OD-dose sensitivity dependence on cooling rate was reduced for the sucrose FAX gel over the standard FAX gel, which has significant implications for uniform dose sensitivity in large gel phantoms. The thermal oxidation rate in the sucrose FAX gel was up to 2.3 times higher than in the standard gel. The OD-dose sensitivity of oxygenated sucrose FAX gels was 4.3 times greater than standard FAX gels, while continued enhancement in OD-dose sensitivity with increased sucrose concentrations beyond 2.0 g/l was found only for the oxygenated sucrose FAX gels. Both the molar absorption coefficient of the ferric ion-xylenol orange complex at 543 nm and gel pH were not affected by the presence of sucrose, with the implication that the higher OD-dose sensitivity of gels with saccharides is due to increased chain reaction production of ferric ions

  20. Optical sensing of HCl with phenol red doped sol-gels

    International Nuclear Information System (INIS)

    Wang Enju; Chow, Kwok-Fan; Wang Wenqun; Wong, Crystal; Yee, Cynthia; Persad, Alvin; Mann, Jonathan; Bocarsly, Andrew

    2005-01-01

    A dye doped sol-gel for the sensing of hydrochloric acid in solution and/or gaseous phase is described. The sol-gel is obtained by acidic hydrolysis of tetraethoxysilane (TEOS) and phenyltriethoxysilane (Ph-TriEOS) in the presence of phenol red (PR) and further spin-coating onto glass slides. The sensitive response is based on an increase of the absorption band at 510 nm of phenol red entrapped in the sol-gel casting when exposed to HCl solution or gas, due to protonation of the dye. The detection limit of the sol-gel response to moisturized gaseous HCl is below 12 ppm, and its response to HCl in solution falls in the range of 0.01-6 M. The sol-gel coating has a response time of less than 40 s in steady-state, and life-time of more than a year. Weak acids such as acetic acid, benzoic acid, salicylate acid, citrate acid, and carbonic acid do not interfere the response. The responses in acid solutions are completely reversible. In the gaseous phase, response of HCl appears to be moisture sensitive