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Sample records for thermogravimetry tg differential

  1. Study and characterization of ammonium diuranate and uranium trioxide by thermogravimetry and differential scanning calorimetry

    International Nuclear Information System (INIS)

    Dantas, J.M.

    1983-01-01

    Thermogravimetry (TG), Differential Thermogravimetry (DTG) and Differential Scanning Calorimetry (DSC) were used to characterize the thermal behavior of ammonium diuranate (ADU) and uranium trioxide (UO 3 ) produced at IPEN'S Chemical Enginnering Department. Compounds characterization was done using the molar ratios among the compounds and the oxides resulting from thermal decomposition. The TG and DTG curves registered for each sample were used for the determination of the following temperatures: - temperature of water evolution (free and crystallized water); - ammonia evolution and oxidation temperature; - ocluded ammonium nitrate decomposition temperature and - oxygen release temperature. The intermediate phases and their thermal stabilities were also identified by TG and DTG and confirmed by DSC curves, DSC curves showed also the exothermic and endothermic behavior of the processes involved. Finally, the great amount of data collected in this study can be handed as a guide by the professionals responsible for the operation of ADU,UO 3 and UF 4 pilot plants. (Author) [pt

  2. Thermal behaviors of mechanically activated pyrites by thermogravimetry (TG)

    International Nuclear Information System (INIS)

    Hu Huiping; Chen Qiyuan; Yin Zhoulan; Zhang Pingmin

    2003-01-01

    The thermal decompositions of mechanically activated and non-activated pyrites were studied by thermogravimetry (TG) at the heating rate of 10 K min -1 in argon. Results indicate that the initial temperature of thermal decomposition (T di ) in TG curves for mechanically activated pyrites decreases gradually with increasing the grinding time. The specific granulometric surface area (S G ), the structural disorder of mechanically activated pyrites were analyzed by X-ray diffraction laser particle size analyzer, and X-ray powder diffraction analysis (XRD), respectively. The results show that the S G of mechanically activated pyrites remains almost constant after a certain grinding time, and lattice distortions (ε) rise but the crystallite sizes (D) decrease with increasing the grinding time. All these results imply that the decrease of T di in TG curves of mechanically activated pyrites is mainly caused by the increase of lattice distortions ε and the decrease of the crystallite sizes D of mechanically activated pyrite with increasing the grinding time. The differences in the reactivity between non-activated and mechanically activated pyrites were observed using characterization of the products obtained from 1 h treatment of non-activated and mechanically activated pyrites at 713 K under inert atmosphere and characterization of non-activated and mechanically activated pyrites exposed to ambient air for a certain period

  3. Study on the characterization and thermal decomposition of uranium compounds by thermogravimetry (TG) and differential scanning calorimetry (DSC)

    International Nuclear Information System (INIS)

    Dantas, J.M.; Abrao, A.

    1981-04-01

    A contribution to the characterization of several uranium compounds obtained at the IPEN' Uranium Pilot Plant is given. Particularly, samples of ammonium diuranate (ADU) and uranium oxides were studied. The main objective was to know the stoichiometry of the ADU and the oxides resulting from its thermal transformation. ADU samples were prepared by batchwise precipitation, stationary dewatering into stove and batchwise thermal decomposition, or, alternatively, continuous precipitation, continuous filtration, continuous drying and continuous thermal decomposition inside a temperature gradient electrical furnace. All ADU were precipitated using NH 3 gas from uranul sulfate or uranyl nitrate solutions. The thermal decomposition of ADU and uranium oxides were studied in an air atmosphere by thermogravimetry (TG) and differential scanning calorimetry (DSC). Any correlation between the parameters of precipitation, drying, calcination and the hystory of the obtaintion of the several uraniumm compounds and their initial and final composition was looked for. Heating program was established to have the U 3 O 8 oxide as the final product. Intermediary phases were tentatively identified. Temperatures at which occurred the absorption water elimination, crystallization water elimination, evolution or oxidation of NH 3 , decomposition of NO -3 ion and oxygen evolution and the exo- and endothermic process for each sample were identified. (Author) [pt

  4. Characterization of Two Different Clay Materials by Thermogravimetry (TG), Differential Scanning Calorimetry (DSC), Dilatometry (DIL) and Mass Spectrometry (MS) - 12215

    Energy Technology Data Exchange (ETDEWEB)

    Post, Ekkehard [NETZSCH Geraetebau GmbH, Wittelsbacherstrasse 42, 95100 Selb (Germany); Henderson, Jack B. [NETZSCH Instruments North America, LLC, 129 Middlesex Turnpike, Burlington, MA 01803 (United States)

    2012-07-01

    An illitic clay containing higher amounts of organic materials was investigated by dilatometry, thermogravimetry and differential scanning calorimetric. The evolved gases were studied during simultaneous TG-DSC (STA) and dilatometer measurements with simultaneous mass spectrometry in inert gas and oxidizing atmosphere. The dilatometer results were compared with the STA-MS results which confirmed and explained the reactions found during heating of the clay, like dehydration, dehydroxylation, shrinkage, sintering, quartz phase transition, combustion or pyrolysis of organics and the solid state reactions forming meta-kaolinite and mullite. The high amount of organic material effects in inert gas atmosphere most probably a reduction of the oxides which leads to a higher mass loss than in oxidizing atmosphere. Due to this reduction an additional CO{sub 2} emission at around 1000 deg. C was detected which did not occur in oxidizing atmosphere. Furthermore TG-MS results of a clay containing alkali nitrates show that during heating, in addition to water and CO{sub 2}, NO and NO{sub 2} are also evolved, leading to additional mass loss steps. These types of clays showed water loss starting around 100 deg. C or even earlier. This relative small mass loss affects only less shrinkage during the expansion of the sample. The dehydroxylation and the high crystalline quartz content result in considerable shrinkage and expansion of the clay. During the usual solid state reaction where the clay structure collapses, the remaining material finally shrinks down to a so-called clinker. With the help of MS the TG steps can be better interpreted as the evolved gases are identified. With the help of the MS it is possible to distinguish between CO{sub 2} and water (carbonate decomposition, oxidation of organics or dehydration/dehydroxylation). The MS also clearly shows that mass number 44 is found during the TG step of the illitic clay at about 900 deg. C in inert gas, which was interpreted

  5. A study of poly(vinyl alcohol thermal degradation by thermogravimetry and differential thermogravimetry

    Directory of Open Access Journals (Sweden)

    Julián Esteban Barrera

    2007-05-01

    Full Text Available The thermal degradation of poly(vinyl alcohol (PVA having different degrees of hydrolysis and molecular weights was studied by thermogravimetry (TGA and differential thermogravimetry (DTGA. Four degradation events were identified whose intensity was related to the degree of hydrolysis. It was verified that the solid-state degradation mechanism for high hydrolysis degrees corresponded to eliminating water-forming side groups in stoichiometric amounts. The presence of acetate groups and lower melting points delayed the polymer’s thermal decomposition at lower hydrolysis degrees. There was no direct correlation in these samples between weight-loss during the first degradation event and the stoichiometric quantities which would be produced by eliminating the side groups. Reaction order and energy activation value qualitative coincidence was found by evaluating experimental data by using Freeman-Carroll and Friedman kinetic models.

  6. Estudo termoanalítico de comprimidos revestidos contendo captopril através de termogravimetria (TG e calorimetria exploratória diferencial (DSC Thermal analysis study of captopril coated tablets by thermogravimetry (TG and differential scanning calorimetry (DSC

    Directory of Open Access Journals (Sweden)

    Giovana Carolina Bazzo

    2005-09-01

    Full Text Available No presente trabalho foram desenvolvidos comprimidos de captopril revestidos com hidroxipropilmetilcelulose (HPMC, Opadry®, polivinilpirrolidona (PVP, Eudragit® E e goma laca. Foi realizado estudo termoanalítico do fármaco e das formulações através de termogravimetria (TG e calorimetria exploratória diferencial (DSC. Através da análise das curvas DSC verificou-se que não houve a ocorrência de interação entre o fármaco e os excipientes lactose, celulose microcristalina, croscarmelose sódica, Aerosil® e talco, utilizados na formulação do comprimido. Através desta técnica detectou-se a possibilidade de interação entre captopril e estearato de magnésio. De acordo com os resultados obtidos através de DSC não foram observadas alterações na cristalinidade do fármaco decorrentes dos processos de compressão e revestimento. A termogravimetria foi utilizada para o estudo da cinética de degradação do captopril e dos comprimidos. Os parâmetros cinéticos foram determinados através do método de Ozawa. Os resultados demonstraram que não houve alteração da estabilidade térmica do captopril na forma de comprimido. A formulação revestida com HPMC foi a que apresentou maior estabilidade térmica, quando comparada às demais formulações de revestimento.In the present study, captopril coated tablets with hydroxypropylmethylcellulose (HPMC, Opadry®, polyvinylpirrolidone (PVP, Eudragit® and shellac were produced. Differential scanning calorimetry (DSC and thermogravimetry (TG were used to evaluate the thermal properties of the drug and the formulations. On the basis of DSC results, captopril was found to be compatible with lactose, microcrystalline cellulose, sodium croscarmellose, Aerosil® and talc. Some possibility of interaction between drug-excipient was observed with magnesium stearate. However, additional techniques to confirm the results obtained are needed. There was no influence of mechanical treatment (tableting

  7. Comparative study by TG and DSC Of membranes polyamide66/bentonite clay nanocomposite; Estudo comparativo por TG e DSC de membranas de nanocompositos poliamida66/argila bentonitica

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, K.M. de; Kojuch, L R; Araujo, E M; Lira, H.L., E-mail: keilamm@ig.com.b [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Lima, F [Universidade Estadual da Paraiba (UEPB), Campina Grande, PB (Brazil). Dept. de Quimica

    2010-07-01

    In this study, it was obtained membranes of nanocomposites polyamide66 with 3 and 5% bentonite clay consists of silicates in layers from the interior of Paraiba. The clay was treated with a quaternary ammonium salt in order to make it organophilic. The membranes were prepared by phase inversion technique from the nanocomposites in solution. The clays were characterized by X-ray diffraction (XRD) and thermogravimetry (TG). Also the membranes were characterized by differential scanning calorimetry (DSC) and TG. The XRD and TG confirmed the presence of salt in the clay and thermal stability of the treated clay. For DSC, it was observed that there was no change in melting temperature of the membranes of nanocomposites compared to membrane pure polyamide66. By TG, it was found that the decomposition of the membranes of polyamide66 with treated clay were higher compared with the untreated clay. (author)

  8. The follow-up of patients with differentiated thyroid cancer and undetectable thyroglobulin (Tg) and Tg antibodies during ablation

    NARCIS (Netherlands)

    Phan, Ha T. T.; Jager, Pieter L.; van der Wal, Jacqueline E.; Sluiter, Wim J.; Plukker, John T. M.; Dierckx, Rudi A. J. O.; Wolffenbuttel, Bruce H. R.; Links, Thera P.

    Objective: This retrospective study describes the rote of serum thyroglobulin (Tg) in relation to tumor characteristics in the prediction of persistent/recurrent disease in patients with differentiated thyroid cancer (DTC) with negative Tg at the time of ablation. Design: Between 1989 and 2006, 94

  9. A Sensitive Tg Assay or rhTSH Stimulated Tg : What's the Best in the Long-Term Follow-Up of Patients with Differentiated Thyroid Carcinoma?

    NARCIS (Netherlands)

    Persoon, Adrienne C. M.; Jager, Pieter L.; Sluiter, Wim J.; Plukker, John T. M.; Wolffenbuttel, Bruce H. R.; Links, Thera P.

    2007-01-01

    Sensitivity of thyroglobulin (Tg) measurement in the follow-up of differentiated thyroid carcinoma (DTC) can be optimized by using a sensitive Tg assay and rhTSH stimulation. We evaluated the diagnostic yield of a sensitive Tg assay and rhTSH stimulated Tg in the detection of recurrences in the

  10. Diagnostic value of Tg and TgAb for metastasis following ablation in patients with differentiated thyroid carcinoma coexistent with Hashimoto thyroiditis.

    Science.gov (United States)

    Chai, Hong; Zhu, Zhao-Jin; Chen, Ze-Quan; Yu, Yong-Li

    2016-08-01

    This study was designed to investigate the clinical value of serum thyroglobulin (Tg) and antithyroglobulin antibody (TgAb) measurements and the cutoff value after ablation in differentiated thyroid carcinoma (DTC) complicated by Hashimoto thyroiditis (HT) with metastasis. We measured serum Tg and TgAb levels and evaluated the disease status in 164 cases of DTC coexistent with HT in pathologically confirmed patients after surgery and post-remnant ablation during a 3-year follow-up. All Tg and TgAb levels were assessed by chemiluminescent immunoassay (IMA). Receiver operating characteristic (ROC) curve analysis was used to evaluate the prognostic value of Tg and TgAb for disease metastasis. The relationship between Tg and TgAb was analyzed using the scatter diagram distribution method. We found that the cutoff values of Tg and TgAb were 1.48 µg/L and 45 kIU/L, respectively. The area under the ROC curve (AUC) of Tg and TgAb was 0.907 and 0.650, respectively. In DTC coexistent with HT patients, the optimal cutoff value correlated with metastasis in Tg and TgAb was 1.48 µg/L and 45 kIU/L, respectively.

  11. Tissue transglutaminase (TG2 activity regulates osteoblast differentiation and mineralization in the SAOS-2 cell line

    Directory of Open Access Journals (Sweden)

    Xiaoxue Yin

    2012-08-01

    Full Text Available Tissue transglutaminase (type II, TG2 has long been postulated to directly promote skeletal matrix calcification and play an important role in ossification. However, limited information is available on the expression, function and modulating mechanism of TG2 during osteoblast differentiation and mineralization. To address these issues, we cultured the well-established human osteosarcoma cell line SAOS-2 with osteo-inductive conditioned medium and set up three time points (culture days 4, 7, and 14 to represent different stages of SAOS-2 differentiation. Osteoblast markers, mineralization, as well as TG2 expression and activity, were then assayed in each stage. Furthermore, we inhibited TG activity with cystamine and then checked SAOS-2 differentiation and mineralization in each stage. The results showed that during the progression of osteoblast differentiation SAOS-2 cells presented significantly high levels of osteocalcin (OC mRNA, bone morphogenetic protein-2 (BMP-2 and collagen I, significantly high alkaline phosphatase (ALP activity, and the increased formation of calcified matrix. With the same tendency, TG2 expression and activity were up-regulated. Furthermore, inhibition of TG activity resulted in a significant decrease of OC, collagen I, and BMP-2 mRNA and of ALP activity and mineralization. This study demonstrated that TG2 is involved in osteoblast differentiation and may play a role in the initiation and regulation of the mineralization processes. Moreover, the modulating effects of TG2 on osteoblasts may be related to BMP-2.

  12. Clinical reevaluation of radioimmunological thyroglobulin (hTg) determination in follow-up of differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Boettger, I.; Kanitz, W.; Pabst, W.H.

    1985-01-01

    A reevaluation of the clinical value of radioimmunological thyroglobulin (hTg) determination during follow-up of differentiated thyroid carcinoma, in general, confirms our previous results already published in 1980 and 1981. A total of 163 patients with differentiated thyroid carcinoma, 53 with papillary and 110 with follicular carcinoma, was studied up to January 1984. 586 sera are included in this study. The differentiation of suspicious from nonsuspicious findings was found to be based upon a cut-off concentration of 10 μg/l. Pathological findings were associated with hTg concentrations above 20 μg/l. Diagnostic accuracy was calculated to be between 95 and 97%, sensitivity of the method in comparison to be radioiodine whole-body scan was 98 versus 83%, respectively, and specificity 94%. At first 5 false negative and 6 false positive hTg findings have been obtained. 7.6% of the patients demonstrated endogeneous hTg antibodies by Boyden test. 7.7% of Boyden test negative sera showed an unacceptable hTg recovery of worse than +- 50%, which was possibly due to endogeneous antibodies. Again, endogenous TSH was able to stimulate hTg secretion in the form of elevated levels, yet did not affect the clinical diagnosis. Examples of the behaviour of hTg levels during follow-up are demonstrated. Specifically, the cases with false hTg findings are discussed. Basically, the conclusions are the same as in 1980 and 1981: hTg determination is able to replace the routinely performed radioiodine whole-body scan during follow-up, if once residual thyroid tissue and metastases have been excluded by means of radioiodine and an optimal follow-up program is used. (orig.) [de

  13. TG-FTIR Study of the Influence of potassium Chloride on Wheat Straw Pyrolysis

    DEFF Research Database (Denmark)

    Jensen, Anker; Dam-Johansen, Kim; Wójtowicz, M.A.

    1998-01-01

    of products into char, tar and gas. In this work, a combination of thermogravimetry and evolved gas analysis by Fourier transform infrared analysis (TG-FTIR) has been applied to study the influence of potassium chloride (KCl) on wheat straw pyrolysis. Raw straw, washed straw and washed straw impregnated...

  14. Thyroglobulin (Tg) recovery testing with quantitative Tg antibody measurement for determining interference in serum Tg assays in differentiated thyroid carcinoma

    NARCIS (Netherlands)

    Persoon, ACM; Links, TP; Wilde, J; Sluiter, WJ; Wolffenbuttel, BHR; van den Ouweland, JMW

    Background: Thyroglobulin (Tg) measurements are complicated by interference from Tg autoantibodies (TgAbs) or heterophilic antibodies (HAMAs). We used a new automated immunochemiluminometric assay (ICMA) with Tg recovery (TgR) on the Nichols Advantage (R) platform to reassess the clinical utility of

  15. Hydriding properties of amorphous Ni-B alloy studied by DSC and thermogravimetry

    International Nuclear Information System (INIS)

    Spassov, T.; Rangelova, V.

    1999-01-01

    The hydrogenation behaviour of melt-spun Ni 81.5 B 18.5 amorphous alloy was studied by means of differential scanning calorimetry (DSC) and thermogravimetry (TG) and compared with the hydriding properties of a Fe-B-Si glass. It was found that the amorphous Ni-B alloy absorbs larger amounts of hydrogen than the Fe-B-Si glass, as the initial kinetics of hydrogen absorption and desorption of both the alloys are comparable. Hydrogen absorption and desorption reactions in Ni-B were observed to proceed with similar rates at ca. 300 K. The hydrogen desorption is revealed in DSC as an endothermic peak in the 350-450 K range, preceding the crystallization peak of the amorphous alloy. The enthalpy of hydrogen desorption (ΔH des =22 kJ/mol H 2 ) for Ni-B was found to be smaller than that for the Fe-B-Si glass, which finding is in contrast to the results on hydrogen diffusion in crystalline αFe and Fe-based alloys and Ni and Ni-based alloys. The hydrogen desorption temperature and enthalpy for Ni 81.5 B 18.5 were found to be independent of the amount of hydrogen absorbed. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  16. Synthesis of CaTiO3 from calcium titanyl oxalate hexahydrate (CTO ...

    Indian Academy of Sciences (India)

    TECS

    2.2 Thermogravimetry (TG), derivative thermogravimetry. (DTG) and differential .... nology for medical processing—A promising option for tomor- row, Mumbai ... E J 1988 in Radioactive waste forms for future (eds) W Lutre and R C Ewing ...

  17. Yeast three-hybrid screen identifies TgBRADIN/GRA24 as a negative regulator of Toxoplasma gondii bradyzoite differentiation.

    Directory of Open Access Journals (Sweden)

    Anahi V Odell

    Full Text Available Differentiation of the protozoan parasite Toxoplasma gondii into its latent bradyzoite stage is a key event in the parasite's life cycle. Compound 2 is an imidazopyridine that was previously shown to inhibit the parasite lytic cycle, in part through inhibition of parasite cGMP-dependent protein kinase. We show here that Compound 2 can also enhance parasite differentiation, and we use yeast three-hybrid analysis to identify TgBRADIN/GRA24 as a parasite protein that interacts directly or indirectly with the compound. Disruption of the TgBRADIN/GRA24 gene leads to enhanced differentiation of the parasite, and the TgBRADIN/GRA24 knockout parasites show decreased susceptibility to the differentiation-enhancing effects of Compound 2. This study represents the first use of yeast three-hybrid analysis to study small-molecule mechanism of action in any pathogenic microorganism, and it identifies a previously unrecognized inhibitor of differentiation in T. gondii. A better understanding of the proteins and mechanisms regulating T. gondii differentiation will enable new approaches to preventing the establishment of chronic infection in this important human pathogen.

  18. Analyzing microporosity with vapor thermogravimetry and gas pycnometry

    NARCIS (Netherlands)

    Dral, A. Petra; ten Elshof, Johan E.

    2018-01-01

    The complementary use of thermogravimetry and pycnometry is demonstrated to expand the toolbox for experimental micropore analysis <1 nm. Thermogravimetry is employed to assess the uptake of water, methanol, ethanol, 1-propanol and cyclohexane vapors in microporous structures at room temperature and

  19. Combustion kinetics of the coke on deactivated dehydrogenation catalysts

    NARCIS (Netherlands)

    Luo, Sha; He, Songbo; Li, XianRu; Li, Jingqiu; Bi, Wenjun; Sun, Chenglin

    2015-01-01

    The coke combustion kinetics on the deactivated catalysts for long chain paraffin dehydrogenation was studied by the thermogravimetry and differential thermogravimetry (TG–DTG) technique. The amount and H/C mole ratio of the coke were determined by the TG and elemental analysis. And the

  20. Anaerobic digestion of solid slaughterhouse waste: study of biological stabilization by Fourier Transform infrared spectroscopy and thermogravimetry combined with mass spectrometry.

    Science.gov (United States)

    Cuetos, María José; Gómez, Xiomar; Otero, Marta; Morán, Antonio

    2010-07-01

    In this paper, Fourier Transform infrared spectroscopy (FTIR) along with thermogravimetric analysis together with mass spectrometry (TG-MS analysis) were employed to study the organic matter transformation attained under anaerobic digestion of slaughterhouse waste and to establish the stability of the digestates obtained when compared with fresh wastes. Digestate samples studied were obtained from successful digestion and failed systems treating slaughterhouse waste and the organic fraction of municipal solid wastes. The FTIR spectra and TG profiles from well stabilized products (from successful digestion systems) showed an increase in the aromaticity degree and the reduction of volatile content and aliphatic structures as stabilization proceeded. On the other hand, the FTIR spectra of non-stable reactors showed a high aliphaticity degree and fat content. When comparing differential thermogravimetry (DTG) profiles of the feed and digestate samples obtained from all successful anaerobic systems, a reduction in the intensity of the low-temperature range (approximately 300 degrees C) peak was observed, while the weight loss experienced at high-temperature (450-550 degrees C) was variable for the different systems. Compared to the original waste, the intensity of the weight loss peak in the high-temperature range decreased in the reactors with higher hydraulic retention time (HRT) whereas its intensity increased and the peak was displaced to higher temperatures for the digesters with lower HRT.

  1. Follow-up of patients with thyroglobulin-antibodies : Rising Tg-Ab trend is a risk factor for recurrence of differentiated thyroid cancer

    NARCIS (Netherlands)

    de Meer, Siegrid G A; Vorselaars, Wessel M C M; Kist, Jakob W; Stokkel, Marcel P M; de Keizer, Bart; Valk, Gerlof D; Borel Rinkes, Inne H M; Vriens, Menno R

    2017-01-01

    PURPOSE: Differentiated thyroid cancer is the most common endocrine malignancy. Recurrences (5-20%) are the main reason for follow-up. Thyroglobulin (Tg) has proven to be an excellent disease marker, but thyroglobulin-antibodies (Tg-Ab) may interfere with Tg measurement, leading to over or

  2. Thermodesorption studies of ammonium nitrate prills by high-resolution thermogravimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, Q.S.M.; Jones, D.E.G. [Natural Resources Canada, CANMET Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2003-07-01

    Ammonium nitrate prills with fuel oil (ANFO) are commonly used in commercial explosives. The wettability of AN is influenced by porosity and surface area. To date, scanning electron microscopy (SEM), mercury porosimetry, and nuclear magnetic resonance (NMR) microscopy have been used to characterize prill porosities. This study used high-resolution thermogravimetry (TG) to investigate the thermodesorption of octane from ammonium nitrate (AN) prills of different porosities. Samples were immersed in octane. Samples of AN prills were monitored over a temperature range between 25 to 120 degrees C. Mass-loss curves were measured to determine the evaporation of excess liquids as well as the rate of octane thermodesorption from the pores and surfaces of the AN prills. An analysis of the curves suggested that the initial mass loss was caused by evaporation of the bulk liquid. The following step represented the thermodesorption of adsorbed octane on the surface of the AN remote from the monolayer. Properties of the surface liquid differed significantly from the bulk liquid as the adsorbate materials interacted with the solid surface. The study demonstrated that the quantity of octane desorbed in the steps correlated with the volume observed in the pores and the amount adsorbed on the surface. Results of the study were then compared with data obtained using SEM. It was concluded that high resolution TG can be used to characterize AN porosity and adsorption capacity. 16 refs., 1 tab., 5 figs.

  3. Thermogravimetry studies on ilmenite nitridation

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar

    2014-12-01

    Full Text Available The present study is based on the possibility of beneficiation of Indian-ilmenite by carbonitrothermic process. The investigations were carried out in two parts. In the first part, thermogravimetric-differential thermogravimetric (TG-DTG experiments were conducted using cold pressed pellets of blended mixtures TiO2-C and FeTiO3-C. The TG experiments were carried out up to 1500 °C at the rate of 10 °C/min under flowing nitrogen gas. The formations of TiN in case of TiO2-C mixture and TiN along with Fe in case of FeTiO3-C mixture were observed. In the second part, the experiments were conducted using similar pellets, prepared under identical conditions, in a resistance heating furnace at 1500 °C. By simple operations of crushing and sieving, the products obtained from the ilmenite-carbon mixture were separated into a fraction enriched in titanium and a fraction depleted in titanium.

  4. Kinetics of Cold-Cap Reactions for Vitrification of Nuclear Waste Glass Based on Simultaneous Differential Scanning Calorimetry - Thermogravimetry (DSC-TGA) and Evolved Gas Analysis (EGA)

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Carmen P.; Pierce, David A.; Schweiger, Michael J.; Kruger, Albert A.; Chun, Jaehun; Hrma, Pavel R.

    2013-12-03

    For vitrifying nuclear waste glass, the feed, a mixture of waste with glass-forming and modifying additives, is charged onto the cold cap that covers 90-100% of the melt surface. The cold cap consists of a layer of reacting molten glass floating on the surface of the melt in an all-electric, continuous glass melter. As the feed moves through the cold cap, it undergoes chemical reactions and phase transitions through which it is converted to molten glass that moves from the cold cap into the melt pool. The process involves a series of reactions that generate multiple gases and subsequent mass loss and foaming significantly influence the mass and heat transfers. The rate of glass melting, which is greatly influenced by mass and heat transfers, affects the vitrification process and the efficiency of the immobilization of nuclear waste. We studied the cold-cap reactions of a representative waste glass feed using both the simultaneous differential scanning calorimetry thermogravimetry (DSC-TGA) and the thermogravimetry coupled with gas chromatography-mass spectrometer (TGA-GC-MS) as complementary tools to perform evolved gas analysis (EGA). Analyses from DSC-TGA and EGA on the cold-cap reactions provide a key element for the development of an advanced cold-cap model. It also helps to formulate melter feeds for higher production rate.

  5. Characteristic Study of Some Different Kinds of Coal Particles Combustion with Online TG-MS-FTIR

    Science.gov (United States)

    Pan, Guanfu

    2018-01-01

    Four kinds of pulverized coal samples from China and Indonesia were studied by thermogravimetry coupled with mass spectrometry and fourier transform infrared spectroscopy (TG-MS-FTIR). The thermal behaviors and gaseous emissions of these coals were analyzed in this work. The results indicate that the relative lower values of H/C ratios, which normally represent the degree of aromatization and ring condensation in coal samples, could lead to the relative more intense thermal reaction. The time-evolved profiles of some typical gas products (i.e., CO, SO2, CH4, NO, NO2, NH3 and etc.) were provided by TG-MS-FTIR, and their variations are different. For all the samples, the releases of SO2 and COS can be found at lower temperature than those of NO and CO. As the temperature increases, the possible conversion of NO2 and NH3 to NO is deduced in this work.

  6. Humidity Induces Changes in the Dimensions of Hydrogel-Coated Wool Yarns

    Directory of Open Access Journals (Sweden)

    Lanlan Wang

    2018-03-01

    Full Text Available Polymeric hydrogel based on acrylic acid (AA and N,N-dimethylacrylamide (DMAA was prepared by photopolymerization reaction, using nano-alumina as the inorganic crosslinker. Hydrogel-coated wool yarns determine their dimensional changes under humidity conditions. Surface morphology of the hydrogel-coated wool yarns was carried out using SEM microscopy. The hydrogel was further characterized by Fourier transformer infrared spectrum (FTIR, gel permeation chromatography (GPC, differential scanning calorimetry (DSC, thermogravimetry (TG and differential thermogravimetry (DTG. This contribution showed that UV-initiated polymerization coating wool yarns can change the functional properties of wool fibers.

  7. Heavy fuel oil pyrolysis and combustion: kinetics and evolved gases investigated by TGA-FTIR

    KAUST Repository

    Abdul Jameel, Abdul Gani; Han, Yunqing; Brignoli, Omar; Telalovic, Selvedin; Elbaz, Ayman M.; Im, Hong G.; Roberts, William L.; Sarathy, Mani

    2017-01-01

    investigated using non-isothermal thermo-gravimetric analysis (TGA) coupled with a Fourier-transform infrared (FTIR) spectrometer. TG and DTG (differential thermo-gravimetry) were used for the kinetic analysis and to study the mass loss characteristics due

  8. Thyroglobulin (Tg) Testing Revisited: Tg Assays, TgAb Assays, and Correlation of Results With Clinical Outcomes.

    Science.gov (United States)

    Netzel, Brian C; Grebe, Stefan K G; Carranza Leon, B Gisella; Castro, M Regina; Clark, Penelope M; Hoofnagle, Andrew N; Spencer, Carole A; Turcu, Adina F; Algeciras-Schimnich, Alicia

    2015-08-01

    Measurement of thyroglobulin (Tg) by mass spectrometry (Tg-MS) is emerging as a tool for accurate Tg quantification in patients with anti-Tg autoantibodies (TgAbs). The objective of the study was to perform analytical and clinical evaluations of two Tg-MS assays in comparison with immunometric Tg assays (Tg-IAs) and Tg RIAs (Tg-RIAs) in a cohort of thyroid cancer patients. A total of 589 samples from 495 patients, 243 TgAb-/252 TgAb+, were tested by Beckman, Roche, Siemens-Immulite, and Thermo-Brahms Tg and TgAb assays, two Tg-RIAs, and two Tg-MS assays. The frequency of TgAb+ was 58%, 41%, 27%, and 39% for Roche, Beckman, Siemens-Immulite, and Thermo-Brahms, respectively. In TgAb- samples, clinical sensitivities and specificities of 100% and 74%-100%, respectively, were observed across all assays. In TgAb+ samples, all Tg-IAs demonstrated assay-dependent Tg underestimation, ranging from 41% to 86%. In TgAb+ samples, the use of a common cutoff (0.5 ng/mL) for the Tg-MS, three Tg-IAs, and the USC-RIA improved the sensitivity for the Tg-MSs and Tg-RIAs when compared with the Tg-IAs. In up to 20% of TgAb+ cases, Tg-IAs failed to detect Tg that was detectable by Tg-MS. In Tg-RIAs false-high biases were observed in TgAb+ samples containing low Tg concentrations. Tg-IAs remain the method of choice for Tg quantitation in TgAb- patients. In TgAb+ patients with undetectable Tg by immunometric assay, the Tg-MS will detect Tg in up to 20% additional cases. The Tg-RIA will detect Tg in approximately 35% cases, but a significant proportion of these will be clinical false-positive results. The undetectable Tg-MS seen in approximately 40% of TgAb+ cases in patients with disease need further evaluation.

  9. Thermogravimetry/mass spectrometry study of woody residues and an herbaceous biomass crop using PCA techniques

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, C.J.; Velo, E.; Puigjaner, L. [Department of Chemical Engineering, ETSEIB, Universitat Politecnica de Catalunya, Avinguda Diagonal 647, G2, E-08028 Barcelona (Spain); Meszaros, E.; Jakab, E. [Institute of Materials and Environmental Chemistry, Chemical Research Center, Hungarian Academy of Sciences, P.O. Box 17, Budapest 1525 (Hungary)

    2007-10-15

    The devolatilization behaviour of pine and beech wood from carpentry residuals and an herbaceous product from an energy plantation (artichoke thistle) was investigated by thermogravimetry/mass spectrometry (TG/MS). The effect of three pre-treatments, hot-water washing, ethanol extraction and their combination, was also studied. Principal component analysis (PCA) was employed to help in the evaluation of the large data set of results. The characteristics of the thermal decomposition of the herbaceous crop are considerably different from that of the woody biomass samples. The evolution profiles of some characteristic pyrolysis products revealed that the thermal behaviour of wood and thistle is still considerably different after the elimination of some of the inorganic ions and extractive compounds, although the macromolecular components of the samples decompose at similar temperatures. With the help of the PCA calculations, the effect of the different pre-treatments on the production of the main pyrolysis products was evidenced. (author)

  10. TG-FTIR, DSC and quantum chemical studies of the thermal decomposition of quaternary methylammonium halides

    International Nuclear Information System (INIS)

    Sawicka, Marlena; Storoniak, Piotr; Skurski, Piotr; Blazejowski, Jerzy; Rak, Janusz

    2006-01-01

    The thermal decomposition of quaternary methylammonium halides was studied using thermogravimetry coupled to FTIR (TG-FTIR) and differential scanning calorimetry (DSC) as well as the DFT, MP2 and G2 quantum chemical methods. There is almost perfect agreement between the experimental IR spectra and those predicted at the B3LYP/6-311G(d,p) level: this has demonstrated for the first time that an equimolar mixture of trimethylamine and a methyl halide is produced as a result of decomposition. The experimental enthalpies of dissociation are 153.4, 171.2, and 186.7 kJ/mol for chloride, bromide and iodide, respectively, values that correlate well with the calculated enthalpies of dissociation based on crystal lattice energies and quantum chemical thermodynamic barriers. The experimental activation barriers estimated from the least-squares fit of the F1 kinetic model (first-order process) to thermogravimetric traces - 283, 244 and 204 kJ/mol for chloride, bromide and iodide, respectively - agree very well with theoretically calculated values. The theoretical approach assumed in this work has been shown capable of predicting the relevant characteristics of the thermal decomposition of solids with experimental accuracy

  11. Molybdenum(V, germanium(IV, aluminum(III and nickel(II adducts with ethyleneurea, ethylenethiourea and propyleneurea: some empirical correlations involving TG and IR data

    Directory of Open Access Journals (Sweden)

    ROBSON F. DE FARIAS

    2006-03-01

    Full Text Available The adducts MoCl5·2eu, MoCl5·2pu, GeCl4·2etu, AlCl3·2pu, AlCl3·3pu, NiCl2·2etu and NiCl2·4etu (eu = ethyleneurea, etu = ethylenethiourea and pu =propyleneurea were synthesized and characterized by elemental analysis (C, H, N, infrared spectroscopy (IR and thermogravimetry (TG. IR Results show that eu and pu coordinate through oxygen, whereas etu coordinates through nitrogen. For all investigated adducts, a single mass loss step associated with the release of ligand molecules is observed. Empirical correlations involving TG and IR data are established.

  12. Kinetic analysis of dechlorination and oxidation of PrOCl by using a non-isothermal TG method

    International Nuclear Information System (INIS)

    Yang, H.C.; Eun, H.C.; Cho, Y.Z.; Lee, H.S.; Kim, I.T.

    2009-01-01

    Thermal dechlorination and oxidation process of praseodymium oxychloride, PrOCl, was studied from the view point of reaction kinetics. On the basis of data of thermogravimetry under different oxygen partial pressures at various heating rates, a kinetic analysis was performed using an isoconversional method and a master plot method. The results of the isoconversional method of TG data suggested that the dechlorination and oxidation of PrOCl followed a single step with activation energy of 112.6 ± 3.4 kJ mol -1 , and from master plot methods, the reaction was described by a linear-contracting phase boundary reaction

  13. On the growth of calcium tartrate tetrahydrate single crystals

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... The grown crystals were characterized by atomic absorption spectroscopy (AAS), X-ray diffraction analysis (XRD), microhardness measurement, Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG) and differential thermal analysis (DTA). The results obtained are compared with the ...

  14. Thermal dehydration of cobalt and zinc formate dihydrates by controlled-rate thermogravimetry (CRTG) and simultaneous X-ray diffractometry-differential scanning calorimetry (XRD-DSC)

    International Nuclear Information System (INIS)

    Arii, T.; Kishi, A.

    1999-01-01

    The thermal dehydration study of the similar hydrated salts, cobalt and zinc formate dihydrates, have been carried out successfully by means of X-ray diffractometry-differential scanning calorimetry (XRD-DSC) and controlled-rate thermogravimetry (CRTG). X-ray diffraction analysis recorded simultaneously indicates that the resulting anhydrous product, Zn(HCO 2 ) 2 , was crystalline, while Co(HCO 2 ) 2 was amorphous.The XRD-DSC data are proven to be invaluable in verifying the interpretation of overlapping processes in thermal events. In addition, these differences in the resulting anhydrous products can be explained from kinetic analysis results based on the CRTG data. The kinetic mechanism governing the dehydration of zinc formate dihydrate is a nucleation and growth process, while in the case of cobalt formate dihydrate a phase boundary controlled reaction is the governing mechanism. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  15. Enthalpies of sublimation of fullerenes by thermogravimetry

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Herrera, Melchor; Campos, Myriam; Torres, Luis Alfonso; Rojas, Aarón, E-mail: arojas@cinvestav.mx

    2015-12-20

    Graphical abstract: - Highlights: • Enthalpies of sublimation of fullerenes were measured by thermogravimetry. • Results of enthalpies of sublimation are comparable with data reported in literature. • Not previously reported enthalpy of sublimation of C{sub 78} is supplied in this work. • Enthalpies of sublimation show a strong dependence with the number of carbon atoms in the cluster. • Enthalpies of sublimation are congruent with dispersion forces ruling cohesion of solid fullerene. - Abstract: The enthalpies of sublimation of fullerenes, as measured in the interval of 810–1170 K by thermogravimetry and applying the Langmuir equation, are reported. The detailed experimental procedure and its application to fullerenes C{sub 60}, C{sub 70}, C{sub 76}, C{sub 78} and C{sub 84} are supplied. The accuracy and uncertainty associated with the experimental results of the enthalpy of sublimation of these fullerenes show that the reliability of the measurements is comparable to that of other indirect high-temperature methods. The results also indicate that the enthalpy of sublimation increases proportionally to the number of carbon atoms in the cluster but there is also a strong correlation between the enthalpy of sublimation and the polarizability of each fullerene.

  16. Thermogravimetric investigations on A(H2O)6BX6 complexes and the formation of ABX6 and ABO3 structures

    NARCIS (Netherlands)

    Heilbron, M.A.; Gellings, P.J.

    1976-01-01

    Thermogravimetry (TG) of A(H2O)6BX6 complexes are presented, with A = Cd2+, Co2+, Cu2+, Fe2+, Mg2+, Mn2+, Ni2+, Pb2+, Zn2+, B=Si4+, Sn4+, Ti4+, Zr4+, and X=Cl−, F−. On a selected number of complexes, differential thermal analyses (DTA) and differential scanning calorimetric measurements (DSC) have

  17. Thermal behaviour of strontium tartrate single crystals grown in gel

    Indian Academy of Sciences (India)

    Thermal behaviour of strontium tartrate crystals grown with the aid of sodium metasilicate gel is investigated using thermogravimetry (TG) and differential thermal analysis (DTA). Effect of magnetic field and dopant (Pb)2+ on the crystal stability is also studied using thermal analysis. This study reveals that water molecules are ...

  18. Thermogravimetry of alpha, omega-diaminoalkanes used in synthesizing zsm-5

    CSIR Research Space (South Africa)

    Howden, MG

    1993-04-01

    Full Text Available Thermogravimetry was determined on a series of alpha, omega-diaminoalkanes, in which the alkane chain contained from three to eight carbon atoms that were located in zeolite ZSM-5 during synthesis. Of the series, 1, 6-diaminohexane functions best...

  19. TG/DTG, FT-ICR Mass Spectrometry, and NMR Spectroscopy Study of Heavy Fuel Oil

    KAUST Repository

    Elbaz, Ayman M.

    2015-11-12

    There is an increasing interest in the comprehensive study of heavy fuel oil (HFO) due to its growing use in furnaces, boilers, marines, and recently in gas turbines. In this work, the thermal combustion characteristics and chemical composition of HFO were investigated using a range of techniques. Thermogravimetric analysis (TGA) was conducted to study the nonisothermal HFO combustion behavior. Chemical characterization of HFO was accomplished using various standard methods in addition to direct infusion atmospheric pressure chemical ionization Fourier transform ion cyclotron resonance mass spectrometry (APCI-FTICR MS), high resolution 1H nuclear magnetic resonance (NMR), 13C NMR, and two-dimensional heteronuclear multiple bond correlation (HMBC) spectroscopy. By analyzing thermogravimetry and differential thermogravimetry (TG/DTG) results, three different reaction regions were identified in the combustion of HFO with air, specifically, low temperature oxidation region (LTO), fuel deposition (FD), and high temperature oxidation (HTO) region. At the high end of the LTO region, a mass transfer resistance (skin effect) was evident. Kinetic analysis in LTO and HTO regions was conducted using two different kinetic models to calculate the apparent activation energy. In both models, HTO activation energies are higher than those for LTO. The FT-ICR MS technique resolved thousands of aromatic and sulfur containing compounds in the HFO sample and provided compositional details for individual molecules of three major class species. The major classes of compounds included species with one sulfur atom (S1), with two sulfur atoms (S2), and purely hydrocarbons (HC). The DBE (double bond equivalent) abundance plots established for S1 and HC provided additional information on their distributions in the HFO sample. The 1H NMR and 13C NMR results revealed that nearly 59% of the 1H nuclei were distributed as paraffinic CH2 and 5% were in aromatic groups. Nearly 21% of 13C nuclei were

  20. Comparison of Thyroglobulin Measurements Using Three Different Immunoassay Kits: A BRAMHS Tg-Plus RIA Kit, a BRAMHS hTg Sensitive Kryptor Kit, and a Beckman Coulter ACCESS Immunoassay Kit

    Directory of Open Access Journals (Sweden)

    Mijin Kim

    2016-09-01

    Full Text Available BackgroundSecond-generation thyroglobulin immunometric assays (Tg-IMAs have been developed with improved sensitivity. Our aim was to compare the diagnostic value of Tg-IMA measurements using a Kryptor (BRAHMS AG kit (Tg-K and an ACCESS (Beckman Coulter kit (Tg-A with that of the first-generation Tg measurement using a Tg-plus (BRAHMS AG kit (Tg+.MethodsWe enrolled 82 differentiated thyroid cancer patients who underwent total thyroidectomy with radioactive iodine remnant ablation and who underwent diagnostic whole body scan using recombinant human thyroid stimulating hormone (rhTSH. The Tg+, Tg-K, and Tg-A were measured before rhTSH administration during levothyroxine treatment (suppressed Tg from the same sample. Serum Tg+ was measured after rhTSH stimulation (stimulated Tg.ResultsSuppressed Tg+ was more significantly correlated with suppressed Tg-K (R2=0.919, P<0.001 than with suppressed Tg-A (R2=0.536, P<0.001. The optimal cut-off values of suppressed Tg+, Tg-K, and Tg-A for predicting stimulated Tg+ of 1 ng/mL were 0.3, 0.2, and 0.2 ng/mL, respectively. The sensitivity, specificity, and accuracy of suppressed Tg+ were 67%, 100%, and 90%, respectively; those of suppressed Tg-K were 83%, 90%, and 88%; those of suppressed Tg-A were 96%, 82%, and 87%, respectively. The positive predictive and negative predictive values of Tg+ were 100% and 87%, respectively; those of Tg-K were 79% and 92%; and those of Tg-A were 73% and 98%.ConclusionWe could not clearly demonstrate which kit had better diagnostic performance after comparison of first-generation Tg measurements with Tg-IMA measurements. Also, there were kit-to-kit variations between Tg-IMA kits. Suppressed Tg measured by Tg-IMA was insufficient to completely substitute for a stimulated Tg measurement.

  1. Nitrogen content determinations in different stages of thermal treatment involved in conversion of ammonium diuranate to uranium metal

    International Nuclear Information System (INIS)

    Shrivastava, K.C.; Shelke, G.P.

    2017-01-01

    Determination of nitrogen content in the uranium metal and uranium oxide based reactor fuels is important to meet the requirement of specifications given by fuel designer. Therefore, a systematic study was carried out to determine the variations in nitrogen content during the conversion of ammonium diuranate (ADU) to uranium oxides (UO 3 and UO 2 ), and finally to uranium metal by inert gas fusion-thermal conductivity detection (IGF-TCD) technique. To understand the measured nitrogen content variations, the thermal decomposition study of ADU was carried out using thermogravimetry (TG)/differential thermogravimetry (DTG) and differential thermal analysis (DTA) in the temperature range of 25-1073 K. Powder X-ray diffraction (XRD) technique was used to confirm the formation of uranium oxide precursors at different temperature. (author)

  2. Thermal decomposition of double selenates of lanthanides (III), yttrium (III) and ammonium

    International Nuclear Information System (INIS)

    Crespi, M.S.

    1989-01-01

    Double selenates of lanthanides, yttrium and ammonium were prepared by treating mixtures of simple selenates with equimolar amounts and then dried in a vacuum desiccator containing anhydrous calcium chloride, protected from light. The compounds were studied using the conventional analytical methods such as infrared absorption spectra, X-ray diffraction, differential thermal analysis (DTA), and thermogravimetry (TG). (author)

  3. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    Energy Technology Data Exchange (ETDEWEB)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D. [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil); Treu-Filho, O. [UNESP – Univ Estadual Paulista, Instituto de Química, São Paulo CEP 14800-900 (Brazil); Bannach, G., E-mail: gilbert@fc.unesp.br [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil)

    2014-01-10

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L){sub 3}, in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand.

  4. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    International Nuclear Information System (INIS)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D.; Treu-Filho, O.; Bannach, G.

    2014-01-01

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L) 3 , in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand

  5. The role of FDG-PET/CT in differentiated thyroid cancer patients with negative iodine-131 whole-body scan and elevated anti-Tg level.

    Science.gov (United States)

    Asa, Sertac; Aksoy, Sabire Yılmaz; Vatankulu, Betül; Aliyev, Anar; Uslu, Lebriz; Ozhan, Meftune; Sager, Sait; Halac, Metin; Sonmezoglu, Kerim

    2014-12-01

    In the follow-up of differentiated thyroid cancer (DTC) after a successful total-near total thyroidectomy and I-131 ablation therapy, anti-thyroglobulin antibodies (anti-Tg) may be persistently or progressively increased in the patients with an undetectable serum thyroglobulin (Tg) level. In these cases, further investigation was performed to search for recurrence/metastases. The aim of our study was clarifying the role of FDG-PET/CT in detecting recurrence/metastasis in patients with DTC with negative serum Tg and elevated anti-Tg level. A total of 40 patients (32 female, 8 male; mean age: 43.15 years (22-65); mean age at diagnosis: 39.08 (16-64)) with DTC who had undetectable serum Tg and elevated anti-Tg level after a successful initial therapy were included in the study. All of the patients had serum anti-Tg of >40 IU/ml and underwent FDG-PET/CT to search for recurrence/metastasis. Twenty patients (50 %) had recurrence/metastasis on FDG-PET/CT while the other 20 had no pathologic findings. Of the 20 patients who had positive FDG-PET/CT, 12 had a histopathological final diagnosis of which 11 were true positive (TP) and 1 was false positive (FP). On the other hand, 16 of the 40 patients had a histopathological final diagnosis of which 11/16 had TP, 1/16 FP, 3/16 false negative (FN) and 1/16 true negative (TN) findings by PET/CT. The final diagnosis was made by clinical follow-up in the remaining 24 patients. Of these, 8 patients were PET positive, and in 1 (12.5 %) of 8 patients a decrease in serum anti-Tg level, in 2 (25 %) patients a saw-toothed pattern and in 5 (62.5 %) a progressive increase in the serum anti-Tg level were noted during the follow-up. Of the 16 of 24 patients who were diagnosed by clinical follow-up, in 8 a (50 %) decrease in serum anti-Tg level, in 6 (37.5 %) a saw-toothed pattern, and in 2 (12.5 %) a progressively increased anti-Tg level was seen. Of the 40 patients, 14 (35 %) had a diagnosis of recurrence/metastasis finally, with

  6. Thermodecomposition of lanthanides (III) and ytrium (III) glucoheptonates

    International Nuclear Information System (INIS)

    Giolito, J.

    1987-01-01

    The lanthanides (III) and yttrium (III) glucoheptonates as well the D-glucoheptono 1-4 lactone were studied using common analytical methods, elemental microanalysis of carbon and hydrogen, thermogravimetry and differential scanning calorimetry. These compounds were prepared from the reaction between the lanthanides (III) and yttrium (III) hydroxides and glucoheptonic acid aqueous solution obtained by means of the delta lactone hydrolysis of this acid. After stoichiometric reaction the compounds were precipitated by the addition of absolute ethanol, washed with the same solvent and dried in desiccator. Thermogravimetric the (TG) curves of the lanthanides glucoheptonates of the ceric group present thermal profiles with enough differences permitting an easy caracterization of each compound and the yttrium (III) glucoheptonate TG curve showed a great similarity with the erbium (III) compound TG curve. The differential scanning calometry (DSC) curves showed endothermic and exothermic peaks by their shape, height and position (temperature) permit an easy and rapid identification of each compound specially if DSC and TG curves were examined simultaneously. (author) [pt

  7. Thermal Behavior and Free-Radical-Scavenging Activity of Phytic Acid Alone and Incorporated in Cosmetic Emulsions

    Directory of Open Access Journals (Sweden)

    André Luis Máximo Daneluti

    2015-07-01

    Full Text Available Phytic acid is a natural compound widely used as depigmenting agent in cosmetic emulsions. Few studies are available in the literature covering the stability and the antioxidating property of this substance, used alone or into emulsions. Therefore, the purpose of this work was to investigate the thermal behavior and antioxidant properties of phytic acid alone and into cosmetic emulsions. The thermal behavior of this substance was evaluated by thermogravimetry (TG/derivative thermogravimetry (DTG and differential scanning calorimetry (DSC and the free-radical-scavenging activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH. TG/DTG and DSC curves allowed evaluation of the thermal behavior of phytic acid. These results showed that the substance presented four stages of mass loss. Thermal decomposition of the material initiated at 150 °C. Thermal behavior of the cosmetic emulsions detected that the addition of phytic acid decreased the thermal stability of the system. DPPH free-radical-scavenging activity showed that phytic acid incorporated into emulsion had no antioxidant capacity compared to BHT. In summary, we concluded that the thermoanalytical techniques (TG and DSC were efficient and reliable in the characterization of phytic acid alone and incorporated into cosmetic emulsions.

  8. Characterization of Irradiated and Non-Irradiated Rubber from Automotive Scrap Tires

    Science.gov (United States)

    Souza, Clécia Moura; Silva, Leonardo G.

    The aim of this work was to characterize the samples of irradiated and non-irradiated rubber from automotive scrap tires. Rubber samples from scrap tires were irradiated at irradiation doses of 200, 400 and 600kGy in an electron beam accelerator. Subsequently, both the irradiated and non-irradiated samples were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, and Fourier transform infrared (FTIR) spectrophotometry.

  9. Oxidation and diffusion process in the ferrous iron-bearing glass fibres near glass temperature

    DEFF Research Database (Denmark)

    Yue, Yuanzheng; Korsgaard, Martin; Kirkegaard, Lise

    2004-01-01

    The Fe2+ oxidation and the network modifier diffusion in the Fe2+-bearing glass fibers are studied using differential scanning calorimetry (DSC), thermogravimetry (TG), and secondary neutral mass spectrometry (SNMS). The results show two couplings: 1) between the Fe2+ oxidation and the network...... of the Fe2+-bearing fibers with an average diameter of 3.5 m by knowing the heat-treatment conditions and vice versa....

  10. Thermal decomposition of lanthanides (III) and yttrium (III) solid complexes from ethyl ene diamine tetraacetic acid

    International Nuclear Information System (INIS)

    Mercadante, A.

    1991-01-01

    Solid state compounds of lanthanides (III) and yttrium derived from ethyl ene diamine tetraacetic acid were prepared from respective basic carbonates, that were neutralized with EDTA stoichiometry quantities. Complexometry with EDTA, thermogravimetry (TG), differential thermal analysis (DTA) and X-ray diffraction have been used in the study of these compounds. The results of complexometry with EDTA as well as TG and DTA curves bed to the stoichiometry of these compounds the following general formula is obeyed: H[Ln(EDTA]. n H 2 O. X-ray powder patterns of these compounds permitted to establish two isomorphous series. The DTA ant TG curves allowed us to study the dehydration process, the thermal stability and thermal decomposition of these compounds. (C.G.C.)

  11. The effect of some wood preservatives on the thermal degradation of Scots pine

    International Nuclear Information System (INIS)

    Tomak, Eylem D.; Baysal, Ergun; Peker, Huseyin

    2012-01-01

    Highlights: ► Scots pine samples were impregnated with 10 commercial wood preservatives. ► Thermal degradation of wood was evaluated by TG, DTG and DTA. ► The thermal behavior of treated wood differed from that of untreated wood. ► Boron containing wood preservatives yielded more charcoal than other preservatives. ► Boric oxide and metal compounds in the formulations may affect char weight. - Abstract: Wood has been a structural material for many years; however, its ability to burn has limited its use in some applications. This study aims to evaluate the effect of commercial wood preservatives having concentration of 4% on the thermal behavior of Scots pine wood, and compare the fire retardant effectiveness of these preservatives with that of boron compounds. Thermal degradation of treated and untreated wood samples was evaluated by thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA). Thermal behavior of treated wood differed from thermal behavior of untreated wood in terms of a high char yield. Results showed that weight loss of wood reduced while char yield increased in the charring phase of the pyrolysis in the boron containing preservative treated wood accompanying with pyrolysis temperature lowered. The highest char yield was obtained from the samples treated with disodium octaborate tetrahydrate in the all treated groups.

  12. Thermal decomposition of irradiated casein molecules

    Energy Technology Data Exchange (ETDEWEB)

    Aly, M A; Elsayed, A A [Biophysics Dept., Faculty of Science, Cairo University, Giza (Egypt)

    1997-12-31

    Non-isothermal studies were carried out using the derivatograph where thermogravimetry (TG), and differential thermogravimetry (DTG) measurements were used to obtain the activation energies of the first and second reactions for casein decomposition before and after exposure to gamma rays and fast neutrons. Cf- 252 was used as a source of fast neutrons associated with gamma rays. TG and DTG patterns were also recorded for casein samples before and after irradiation with 1 Gy gamma-rays of 0.662 MeV from Cs - 137. However, no change in a activation energies were observed after exposure to gamma-irradiation. On the other hand, the activation energies for first and second reactions were found to be smaller at 0.4 m Gy than that at lower and higher neutron doses. However, no change in activation energies was observed after {gamma} irradiation. It is concluded from the present study that destruction of casein molecules by low level fast neutron doses may lead to changes of shelf storage period milk. 3 figs., 1 tab.

  13. Study of Lactic Acid Thermal Behavior Using Thermoanalytical Techniques

    Directory of Open Access Journals (Sweden)

    Andrea Komesu

    2017-01-01

    Full Text Available Actually, there is a growing interest in the biotechnological production of lactic acid by fermentation aiming to substitute fossil fuel routes. The development of an efficient method for its separation and purification from fermentation broth is very important to assure the economic viability of production. Due to its high reactivity and tendency to decompose at high temperatures, the study of lactic acid thermal behavior is essential for its separation processes and potential application. In the present study, differential scanning calorimetry (DSC analyses showed endothermic peaks related to the process of evaporation. Data of thermogravimetry (TG/DTG were correlated to Arrhenius and Kissinger equations to provide the evaporation kinetic parameters and used to determine the vaporization enthalpy. Activation energies were 51.08 and 48.37 kJ·mol−1 and frequency values were 859.97 and 968.81 s−1 obtained by Arrhenius and Kissinger equations, respectively. Thermogravimetry, coupled with mass spectroscopy (TG-MS, provided useful information about decomposition products when lactic acid was heated at 573 K for approximately 30 min.

  14. Sub-Tg enthalpy relaxation in an extremely unstable oxide glass and its implication for structural heterogeneity

    DEFF Research Database (Denmark)

    Zhang, Yanfei; Hu, L.N.; Liu, S.J.

    2013-01-01

    We study the sub-Tg relaxation in an extremely unstable glass former, i.e., 65SiO2-35Al2O3, and its relation to structural heterogeneity (e.g., structurally ordered domains in glass matrix). This is done by hyperquenching (~106 K/s) the liquid, then annealing the hyperquenched glass below Tg...... and subsequently scanning the annealed hyperquenched glass in a differential scanning calorimeter. The results show that structural ordering can take place even below Tg. An endothermic pre-peak is observed when the hyperquenched sample is annealed at 0.75Tg for sufficiently long time, which is, however, much...... weaker compared to that of stable glass formers subjected to same annealing conditions. We also investigate the effect of the sub-Tg annealing on crystallization above Tg. The results imply that some structurally ordered domains exist already in the liquid state. The ordered domains lower the activation...

  15. Clinical electron beam dosimetry: transition from AAPM TG-25 to AAPM TG-70

    International Nuclear Information System (INIS)

    Mihailidis, Dimitris

    2017-01-01

    The absolute calibration of clinical electron beams is increasingly based on TG-51 protocol. In addition, recently published dosimetry data on electrons beams bring up the question of how would one need to modify the widely used TG-25 that originally was based on TG-21 calibration protocol? The answer to the question is given by the recently published TG-70. This new protocol operates as supplement and update to TG-25 on issues that need to be modified because of TG-51 approach to electron dosimetry and because of newer data on clinical electron beams. It describes in detail the procedure of converting measured depth-ionization curves with ion chambers into depth-dose curves, making use of recently published stopping-power ratios and other conversion factors. It also describes the use of water equivalent phantoms to perform relative electron dosimetry based on recently published conversions factors. The report discusses small and irregularly shaped electron field dosimetry using the concept of lateral buildup ratio (LBR) as an avenue to evaluate electronic equilibrium and compute dose per MU for those fields. Finally, it gives some common clinical examples where electron beam dosimetry are applied

  16. Fragility of chalcogenide glass in relation to characteristic temperature T0/Tg

    Science.gov (United States)

    Shaker, A. M.; Shanker Rao, T.; Lilly Shanker Rao, T.; Venkataraman, K.

    2018-03-01

    The present study reports the mutual relationship between the fragility index m and the characteristic temperature T0/Tg. The fragility of the chalcogenide amorphous glass of Ge10Se50Te40 is calculated by utilizing glass transition temperature (Tg) measured by DSC (Differential Scanning Calorimetry) at different heating rates (β) in the range 5 to 20 K/min. Vogel-Fulcher-Tammann (VFT) equation is fitted to the data of Tg. In addition to the VFT method, three other methods are also used to evaluate m. The fragility index m of the Ge10Se50Te40 system showed the trend of decrease with increasing heating rate but remained stable around 22 for the heating rate 10 K/min. The value of m for the glass is near the lower limit (m ≈ 16) this indicates the alloy is a strong glass forming material in accordance of Angell’s interpretation of fragility. The calculated values of characteristic temperature T0/Tg is very close to 1 which also indicates that clearly the system is most fragile.

  17. FXIIIA and TGF-beta over-expression produces normal musculo-skeletal phenotype in TG2-/- mice.

    Science.gov (United States)

    Tarantino, U; Oliva, F; Taurisano, G; Orlandi, A; Pietroni, V; Candi, E; Melino, G; Maffulli, N

    2009-04-01

    Transglutaminase (TGs) enzymes and proteins crosslinking have for long time been implicated in the formation of hard tissue development, matrix maturation and mineralization. Among the TGs family members, in the context of connective tissue formation, TG2 and Factor XIII are expressed in cartilage by hypertrophic chondrocytes. Here, we analyse the morphological consequences of TG2 deficiency, during the development of skeletal elements. When TG2 is absent, there are not gross abnormalities in the development of the skeletal system, probably from compensatory mechanisms resulting in increased expression of FXIIIA and TGF-beta 1. In vivo other TGs may be involved in promoting chondrocytes and osteoblast differentiation and matrix mineralisation.

  18. Characterization and thermal stability of uranium peroxides by thermogravimetry and differential scanning calorimetry

    International Nuclear Information System (INIS)

    Souza Junior, P.T. de; Abrao, A.

    1982-01-01

    The characterization and thermal behaviour of uranium peroxide samples prepared by precipitation with hydrogen peroxide from uranyl nitrate solution is described. The latter was obtained by dissolution of ammonium diuranate and ammonium uranyl tricarbonate. TG and DTG curves were recorded in the temperature range from room temperature to 700 0 C. DSC curves were recorded from room temperature to 600 0 C. The heating rate was 5 0 C/min. Based upon the DTG curves of a great number of samples, the uranium peroxides were classified in five groups. The collected information was used to recognise the temperature at which the peroxide decomposes and to know its sequential conversion to UO 3 and U 3 O 8 , the evolution of molecules of water of crystallization and absorption, and the elimination of occluded nitrate ions. The results allowed to conclude that no NH + 4 nor H 2 O 2 molecules were occluded by uranium peroxide. The stoichiometric composition of representative samples for the five groups is indicated. (Author) [pt

  19. Thermal annealing of natural, radiation-damaged pyrochlore

    Energy Technology Data Exchange (ETDEWEB)

    Zietlow, Peter; Beirau, Tobias; Mihailova, Boriana; Groat, Lee A.; Chudy, Thomas; Shelyug, Anna; Navrotsky, Alexandra; Ewing, Rodney C.; Schlüter, Jochen; Škoda, Radek; Bismayer, Ulrich

    2017-01-01

    Abstract

    Radiation damage in minerals is caused by the α-decay of incorporated radionuclides, such as U and Th and their decay products. The effect of thermal annealing (400–1000 K) on radiation-damaged pyrochlores has been investigated by Raman scattering, X-ray powder diffraction (XRD), and combined differential scanning calorimetry/thermogravimetry (DSC/TG). The analysis of three natural radiation-damaged pyrochlore samples from Miass/Russia [6.4 wt% Th, 23.1·10

  20. Vaporization of Samarium trichloride studied by thermogravimetry

    International Nuclear Information System (INIS)

    Esquivel, Marcelo R.; Pasquevich, Daniel M.

    2003-01-01

    In the present work, the vaporization reaction of SmCl 3 (l) obtained from the 'in situ' reaction of Sm 2 O 3 (s) and Cl 2 (g)-C(s) was studied by thermogravimetry under controlled atmosphere. The effects of both the temperature between 825 C degrees and 950 C degrees and the total flow gas on the vaporization rate of the following reaction: SmCl 3 (l) = SmCl 3 (g) were analyzed. The vaporization rate of the process was found to be independent of then total gas flow rate and highly dependent on the temperature. E ap calculation led to a value of 240 ± 10 kJ.mol -1 . A comparison between this value and that of the molar enthalpy of vaporization allow to the conclusion that the reaction occur in conditions near to equilibrium. The SmCl 3 identity was determined by X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). (author)

  1. Selective dehydration of bio-ethanol to ethylene catalyzed by lanthanum-phosphorous-modified HZSM-5: influence of the fusel.

    Science.gov (United States)

    Hu, Yaochi; Zhan, Nina; Dou, Chang; Huang, He; Han, Yuwang; Yu, Dinghua; Hu, Yi

    2010-11-01

    Bio-ethanol dehydration to ethylene is an attractive alternative to oil-based ethylene. The influence of fusel, main byproducts in the fermentation process of bio-ethanol production, on the bio-ethanol dehydration should not be ignored. We studied the catalytic dehydration of bio-ethanol to ethylene over parent and modified HZSM-5 at 250°C, with weight hourly space velocity (WHSV) equal to 2.0/h. The influences of a series of fusel, such as isopropanol, isobutanol and isopentanol, on the ethanol dehydration over the catalysts were investigated. The 0.5%La-2%PHZSM-5 catalyst exhibited higher ethanol conversion (100%), ethylene selectivity (99%), and especially enhanced stability (more than 70 h) than the parent and other modified HZSM-5. We demonstrated that the introduction of lanthanum and phosphorous to HZSM-5 could weaken the negative influence of fusel on the formation of ethylene. The physicochemical properties of the catalysts were characterized by ammonia temperature-programmed desorption (NH(3)-TPD), nitrogen adsorption and thermogravimetry (TG)/differential thermogravimetry (DTG)/differential thermal analysis (DTA) (TG/DTG/DTA) techniques. The results indicated that the introduction of lanthanum and phosphorous to HZSM-5 could inhibit the formation of coking during the ethanol dehydration to ethylene in the presence of fusel. The development of an efficient catalyst is one of the key technologies for the industrialization of bio-ethylene.

  2. The effect of some wood preservatives on the thermal degradation of Scots pine

    Energy Technology Data Exchange (ETDEWEB)

    Tomak, Eylem D., E-mail: eylemdizman@yahoo.com [Karadeniz Technical University, Faculty of Forestry, Forest Industrial Engineering Department, 61080 Trabzon (Turkey); Baysal, Ergun, E-mail: bergun@mu.edu.tr [Mugla University, Faculty of Technology, Department of Wood Science and Technology, Kotekli, 48000 Mugla (Turkey); Peker, Huseyin, E-mail: peker100@hotmail.com [Artvin Coruh University, Faculty of Forestry, Forest Industrial Engineering Department, 06100 Artvin (Turkey)

    2012-11-10

    Highlights: Black-Right-Pointing-Pointer Scots pine samples were impregnated with 10 commercial wood preservatives. Black-Right-Pointing-Pointer Thermal degradation of wood was evaluated by TG, DTG and DTA. Black-Right-Pointing-Pointer The thermal behavior of treated wood differed from that of untreated wood. Black-Right-Pointing-Pointer Boron containing wood preservatives yielded more charcoal than other preservatives. Black-Right-Pointing-Pointer Boric oxide and metal compounds in the formulations may affect char weight. - Abstract: Wood has been a structural material for many years; however, its ability to burn has limited its use in some applications. This study aims to evaluate the effect of commercial wood preservatives having concentration of 4% on the thermal behavior of Scots pine wood, and compare the fire retardant effectiveness of these preservatives with that of boron compounds. Thermal degradation of treated and untreated wood samples was evaluated by thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA). Thermal behavior of treated wood differed from thermal behavior of untreated wood in terms of a high char yield. Results showed that weight loss of wood reduced while char yield increased in the charring phase of the pyrolysis in the boron containing preservative treated wood accompanying with pyrolysis temperature lowered. The highest char yield was obtained from the samples treated with disodium octaborate tetrahydrate in the all treated groups.

  3. Preparation, characterization and thermal behaviour study of 4-dimethyl amino benzal pyruvate of lanthanides (III) and yttrium (III) in solid state

    International Nuclear Information System (INIS)

    Miyano, M.H.

    1990-01-01

    Solid state compounds involving Ln and DMBP, where Ln trivalent lanthanides (except promethium) and yttrium; DMBP 4-dimethyl amino benzylidene pyruvate, were prepared by addition of ligand to the corresponding metal ions chlorides, both in aqueous solution. The precipitates were washed with distilled water and dried at 40 0 C in a forced circulation oven. Complexometry with EDTA, thermogravimetry (TG), differential thermal analysis (DTA), infra-red absorption and X-ray diffraction have been used in the study of these compounds. (author)

  4. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    International Nuclear Information System (INIS)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte; Fonseca, Gabriel Paiva; Holt, Randy; Rusch, Thomas; Beaulieu, Luc; Verhaegen, Frank

    2014-01-01

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy ( w,m ) and dose to medium (D m,m ), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D 90 to PTV was reduced by between ∼4% and ∼40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose is also reduced by 10%–15% due to the absence of backscatter not accounted for in TG-43. The balloon applicator also contributed to the reduced dose. Other ROIs showed a difference depending on the method of dose reporting. Conclusions: TG-186-based calculations produce results that are different from TG-43 for the Axxent source. The differences depend strongly on the method of dose reporting. This study highlights the importance of backscatter to peak skin dose. Tissue heterogeneities, applicator, and patient geometries demonstrate the need for a more robust dose calculation method for low energy brachytherapy sources

  5. Vapour phase corrosion inhibitors from South African renewable resources and their evaluation

    CSIR Research Space (South Africa)

    Vuorinen, E

    2006-02-01

    Full Text Available -pressure measurement methods require specialised instruments and are labour-intensive. Thermal analysis techniques, such as thermogravimetry (TG), provide a simple experimental set-up. TG also allows rapid and convenient estimation, using small amounts of substances...

  6. Quantification of water and silanol species on various silicas by coupling IR spectroscopy and in-situ thermogravimetry.

    Science.gov (United States)

    Gallas, Jean-Paul; Goupil, Jean-Michel; Vimont, Alexandre; Lavalley, Jean-Claude; Gil, Barbara; Gilson, Jean-Pierre; Miserque, Olivier

    2009-05-19

    Five silica samples (four precipitated silicas provided by commercial suppliers and one with the MCM-41 structure) have been studied by infrared spectroscopy and by a homemade thermogravimetry-infrared spectrum (TG-IR) setup. The silanol amount, accessibility to water, and different alcohols, and the affinity to water of these various silicas were compared and quantified. TG-IR measurements allowed the precise determination of the integrated molar absorption coefficient of the (nu+delta)OH band, epsilon(nu+delta)OH=(0.16+/-0.01) cm micromol(-1). It is independent of the sample origin and the concentration of silanol groups on silicas. For the precipitated dried samples evacuated at room temperature, the silanol concentration COH varies between 3.6 and 7.0 mmol g(-1). It is 5.3 mmol g(-1) in the case of the MCM-41 sample. Exchange experiments with D2O, followed by back-exchanges with different alcohols (methanol, propan-2-ol, 2-methyl-propan-2-ol, and 3-ethyl-pentan-3-ol) have been followed by infrared spectroscopy. All of the silanols of the MCM-41 sample are accessible to water and alcohol molecules. By contrast, about 20% of the silanols in precipitated samples are not exchanged by D2O (internal silanols). Accessibility decreases with alcohol size; the main effect is relative to methanol. Taking into account the sample specific surface areas and the silanol accessibility to D2O, the surface silanol density of precipitated silicas is close to 8 OH per nm2, at maximum coverage. At variance, the silanol surface density of the MCM silica is much lower, 4 OH per nm2. The TG-IR setup has also been used to determine the amount of water adsorbed on silicas through the intensity of the deltaH2O band. It varies linearly with the concentration of adsorbed water, whatever the silica sample. The integrated molar absorption coefficient of two bands, epsilondeltaH2O=(1.53+/-0.03) cm micromol(-1) and epsilon(nu+delta)H2O=(0.22+/-0.01) cm micromol(-1), have been determined. The

  7. Thermal studies on unirradiated and γ-irradiated polymer of allyl diglycol carbonate

    International Nuclear Information System (INIS)

    Kalsi, P.C.; Pandey, A.K.; Iyer, R.H.; Singh Mudher, K.D.

    1995-01-01

    The thermal decomposition of unirradiated and γ-irradiated (5.93-15.5 MRad dose range) allyl diglycol carbonate polymer (trade name, CR-39) was studied by thermogravimetry (TG) and differential thermal analysis (DTA). These studies indicate four main decomposition steps in CR-39 polymer in air. Assessment of the influence of radiation dose on the above range shows that while the 5.93 MRad γ-irradiated polymer CR-39 degrades in three steps, the 15.5 MRad γ-irradiated polymer degrades in only two steps. The kinetics of the different stages of degradation were also evaluated from the TG curves. Irradiation enhances the decomposition rate and the effect increases further with increasing radiation dose. The activation energy values calculated for all the decomposition stages decrease on irradiation

  8. Analysis of (NH4)2SO4/(NH4)H2PO4 mixtures by thermogravimetry and X-ray diffraction

    International Nuclear Information System (INIS)

    Perez, Jose; Perez, Eduardo; Vas, Beatriz del; Garcia, Luis; Serrano, Jose Luis

    2006-01-01

    (NH 4 ) 2 SO 4 and (NH 4 )H 2 PO 4 are the principal components in the powder material used in fire extinguishers. In this paper the mutual influence in their thermal decomposition is investigated by thermogravimetry. Two methods for the quantification of both salts in mixtures (NH 4 ) 2 SO 4 /(NH 4 )H 2 PO 4 are proposed. The first employs thermogravimetry and is based on the measurement of the mass fraction in the 500-550 deg. C interval, once (NH 4 ) 2 SO 4 has totally decomposed to yield gaseous products. The second uses some selected peaks in the X-ray diffractogram

  9. Characterization of thermal reaction of aluminum/copper (II) oxide/poly(tetrafluoroethene) nanocomposite by thermogravimetric analysis, differential scanning calorimetry, mass spectrometry and X-ray diffraction

    International Nuclear Information System (INIS)

    Li, Xiangyu; Yang, Hongtao; Li, Yan-chun

    2015-01-01

    Highlights: • The thermal reaction properties of the Al/CuO/PTFE nanocomposite were investigated. • The Al/PTFE and CuO/PTFE nanocomposites were prepared and tested for comparison. • TG/DSC–MS and XRD analysis were performed. • PTFE is oxidizing Al and reducing CuO during the thermal decomposition. - Abstract: The application of fluoropolymers as reactive agent in energetic materials have attracted significant interest recently. In this study, the thermal reaction properties of the aluminum nanoparticles/copper (II) oxide nanoparticles/poly(tetrafluoroethene) (Al-NPs/CuO-NPs/PTFE) nanocomposite (mass ratio of Al-NPs/CuO-NPs/PTFE = 20/60/20) were investigated by means of thermogravimetry/differential scanning calorimetry–mass spectrometry (TG/DSC–MS) and X-ray diffraction (XRD) analyses. The Al-NPs/PTFE (mass ratio of Al-NPs/PTFE = 50/50) and CuO-NPs/PTFE (mass ratio of CuO-NPs/PTFE = 75/25) nanocomposites were also prepared and tested for comparison. It is observed that PTFE is acting as both oxidizer and reducer during the thermal decomposition process of Al-NPs/CuO-NPs/PTFE nanocomposites. Before 615 °C, PTFE is oxidized by CuO-NPs and oxidizing Al-NPs, resulting mass reduction. After 615 °C, the excessive aluminum and copper (I)/copper (II) oxide will proceed the exothermic condensed phase reaction.

  10. Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology

    International Nuclear Information System (INIS)

    Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

    2016-01-01

    Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH_3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH_3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. - Highlights: • Hazardous AMFR material was treated by slow pyrolysis reaction. • TG-FTIR-MS were used to study the N conversion for pyrolysis gas and bio-oil. • NH_3 and HCN were observed as the main N-containing gas species. • XPS were used to study the N conversion for pyrolysis char. • Stable species, such as N-oxide and quaternary-N, were

  11. Tissue transglutaminase (TG-2) modified amniotic membrane: a novel scaffold for biomedical applications

    International Nuclear Information System (INIS)

    Chau, David Y S; Brown, Sheridan V; Ghaemmaghami, Amir M; Mather, Melissa L; Hutter, Victoria; Tint, Naing L; Rose, Felicity R A J; Dua, Harminder S

    2012-01-01

    The amniotic membrane (AM) is considered as a natural cell culture substrate and has occasionally been exploited in regenerative medicine especially for ocular surface reconstruction and dermal wound healing applications. However, its use is limited by its relatively weak mechanical strength, difficulty during manual handling and susceptibility to proteolytic degradation in vivo. Therefore, in this study we aimed to enhance the mechanical and biological characteristics of the AM by enzymatically cross-linking it using tissue transglutaminase (TG)—a calcium-dependent enzyme capable of forming stable ε(γ-glutamyl)lysine cross-linkages. Using a biological catalyst such as TG does not only prevent denaturation during sample preparation but also minimizes the potential of residual chemical cross-linking agents compared to alternative methodologies. Human AM, sourced from elective caesarean sectioning, were treated with TG, bovine serum albumin and/or a no-treatment control. Samples were then compared in terms of their physical and (scanning electron microscopy (SEM), transparency, mechanical strength, susceptibility to proteolytic degradation) biological characteristics (in vitro cell culture, activation of dendritic cells (DC)) and their in vivo biocompatibility/angiogenic capacity (chick chorioallantoic membrane assay). TG-treated AM exhibited enhanced mechanical strength and greater resistance to proteolytic/collagenase degradation compared to the control(s). SEM imaging of the TG-treated membrane summarized a significantly closer association and greater interconnectivity of individual collagen fibres yet it had no effect on the overall transparency of the AM. In vitro cell culture demonstrated no detrimental effect of TG-treatment on the AM in terms of cell attachment, spreading, proliferation and differentiation. Moreover, an ‘immune response’ was not elicited based on extended in vitro culture with human-monocyte-derived DC. Interestingly, the TG

  12. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source.

    Science.gov (United States)

    White, Shane A; Landry, Guillaume; Fonseca, Gabriel Paiva; Holt, Randy; Rusch, Thomas; Beaulieu, Luc; Verhaegen, Frank; Reniers, Brigitte

    2014-06-01

    The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (Dw,m) and dose to medium (Dm,m), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D90 to PTV was reduced by between ~4% and ~40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose is also reduced by 10%-15% due to the absence of backscatter not accounted for in TG-43. The balloon applicator also contributed to the reduced dose. Other ROIs showed a difference depending on the method of dose reporting. TG-186-based calculations produce results that are different from TG-43 for the Axxent source. The differences depend strongly on the method of dose reporting. This study

  13. TU-B-304-00: The Aftermath of TG-142

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Although published in 2009, the AAPM TG-142 report on accelerator quality assurance still proves a challenge for full clinical implementation. The choice of methodologies to satisfy TG-142 requirements is critical to a successful application. Understanding the philosophy of TG-142 can help in creating an institution-specific QA practice that is both efficient and effective. The concept of maintaining commissioned beam profiles is still found confusing. The physicist must also consider technologies not covered by TG-142 (i.e. arc therapy techniques). On the horizon is TG-198 report on implementing TG-142. Although the community still lacks a final TG-100 report, performing a failure-mode -and-effects analysis and statistical process control analysis to determine the institution-specific clinical impact of each TG-142 test may be useful for identifying trends for pro-active surveillance. Learning Objectives: To better understand the confusing and controversial aspects of TG-142. To understand what is still missing from TG-142 and how to account for these tests in clinical practice To describe which QA tests in TG-142 yield the largest potential clinical result if not discovered.

  14. TU-B-304-01: The Aftermath of TG-142

    Energy Technology Data Exchange (ETDEWEB)

    Klein, E. [Washington University (United States)

    2015-06-15

    Although published in 2009, the AAPM TG-142 report on accelerator quality assurance still proves a challenge for full clinical implementation. The choice of methodologies to satisfy TG-142 requirements is critical to a successful application. Understanding the philosophy of TG-142 can help in creating an institution-specific QA practice that is both efficient and effective. The concept of maintaining commissioned beam profiles is still found confusing. The physicist must also consider technologies not covered by TG-142 (i.e. arc therapy techniques). On the horizon is TG-198 report on implementing TG-142. Although the community still lacks a final TG-100 report, performing a failure-mode -and-effects analysis and statistical process control analysis to determine the institution-specific clinical impact of each TG-142 test may be useful for identifying trends for pro-active surveillance. Learning Objectives: To better understand the confusing and controversial aspects of TG-142. To understand what is still missing from TG-142 and how to account for these tests in clinical practice To describe which QA tests in TG-142 yield the largest potential clinical result if not discovered.

  15. TU-B-304-02: Quantitative FMEA of TG-142

    Energy Technology Data Exchange (ETDEWEB)

    O’Daniel, J. [Duke University Medical Center (United States)

    2015-06-15

    Although published in 2009, the AAPM TG-142 report on accelerator quality assurance still proves a challenge for full clinical implementation. The choice of methodologies to satisfy TG-142 requirements is critical to a successful application. Understanding the philosophy of TG-142 can help in creating an institution-specific QA practice that is both efficient and effective. The concept of maintaining commissioned beam profiles is still found confusing. The physicist must also consider technologies not covered by TG-142 (i.e. arc therapy techniques). On the horizon is TG-198 report on implementing TG-142. Although the community still lacks a final TG-100 report, performing a failure-mode -and-effects analysis and statistical process control analysis to determine the institution-specific clinical impact of each TG-142 test may be useful for identifying trends for pro-active surveillance. Learning Objectives: To better understand the confusing and controversial aspects of TG-142. To understand what is still missing from TG-142 and how to account for these tests in clinical practice To describe which QA tests in TG-142 yield the largest potential clinical result if not discovered.

  16. Clinical utility of an automated immunochemiluminometric thyroglobulin assay in differentiated thyroid carcinoma

    NARCIS (Netherlands)

    Persoon, ACM; Van den Ouweland, JMW; Wilde, J; Kema, IP; Wolffenbuttel, BHR; Links, TP

    Background: Thyroglobulin (Tg) measurements are important in the follow-up of patients with differentiated thyroid carcinoma (DTC). We evaluated the analytical and clinical performance of a new automated immunochemiluminometric assay for Tg (Tg-ICMA; Nichols Advantage Tg; Nichols Institute

  17. hermal decomposition of irradiated casein molecules

    International Nuclear Information System (INIS)

    Ali, M.A.; Elsayed, A.A.

    1998-01-01

    NON-Isothermal studies were carried out using the derivatograph where thermogravimetry (TG) and differential thermogravimetry (DTG) measurements were used to obtain the activation energies of the first and second reactions for casein (glyco-phospho-protein) decomposition before and after exposure to 1 Gy γ-rays and up to 40 x 1 04 μg Gy fast neutrons. 25C f was used as a source of fast neutrons, associated with γ-rays. 137 Cs source was used as pure γ-source. The activation energies for the first and second reactions for casein decomposition were found to be smaller at 400 μGy than that at lower and higher fast neutron doses. However, no change in activation energies was observed after γ-irradiation. it is concluded from the present study that destruction of casein molecules by low level fast neutron doses may lead to changes of shelf storage period of milk

  18. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte, E-mail: brigitte.reniers@maastro.nl [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN (Netherlands); Fonseca, Gabriel Paiva [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP, São Paulo CP 11049, 05422-970 (Brazil); Holt, Randy; Rusch, Thomas [Xoft, A Subsidiary of iCAD, Sunnyvale, California 94085-4115 (United States); Beaulieu, Luc [Centre Hospitalier Universitaire de Québec Université Laval, Radio-Oncologie et Centre de Recherche en Cancérologie de l’Université Laval, Québec, Québec G1R 2J6 Canada (Canada); Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Department of Oncology, McGill University, Montreal, Quebec H3G 1A4 (Canada)

    2014-06-15

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (<50 kV) brachytherapy system used in accelerated partial breast irradiation (APBI). Breast tissue is a heterogeneous tissue in terms of density and composition. Dosimetric calculations of seven APBI patients treated with Axxent were made using a model-based Monte Carlo platform for a number of tissue models and dose reporting methods and compared to TG-43 based plans. Methods: A model of the Axxent source, the S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (D{sub w,m}) and dose to medium (D{sub m,m}), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D{sub 90} to PTV was reduced by between ∼4% and ∼40%, depending on the

  19. Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology.

    Science.gov (United States)

    Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

    2016-04-01

    Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. The n-butyl amine TPD measurement of Brönsted acidity for solid catalysts by simultaneous TG/DTG-DTA

    Science.gov (United States)

    Sasca, V.; Avram, Livia; Verdes, Orsina; Popa, A.

    2010-06-01

    The method for Brönsted acidity measurement based on TPD of alkyl amines desorption by gas-chromatography or thermogravimetry was adapted for simultaneous TG/DTG-DTA analysis. The acidity measurements were focused on the 12-tungstophosphoric acid (H 3PW 12O 40) and its salts, especially with Cesium since these posses the highest Brönsted acidity and they are among the most interesting catalysts. The n-butyl amine (NBA) desorption takes place in three steps for Cs xH 3- xPW 12O 40, x = 0-2, and four steps for the Cs 2.5H 0.5PW 12O 40. The steps of desorption correspond to the release of NBA molecules in stages, as NBA or butene molecules resulted from the Hofmann elimination reaction and NH 3 + H 2O formed by decomposition of ammonium salt. The quantities of desorption products, C 4H 8 and NH 3 + H 2O, corresponding to the stages with the maximum desorption rates at 400-420 °C, respectively 560-600 °C, are in the stoichiometric ratio with the Brönsted acidity.

  1. Copolymerization of carbon monoxide and styrene catalyzed by resin-supported palladium polymer

    Directory of Open Access Journals (Sweden)

    2007-02-01

    Full Text Available Polyketone was prepared by the copolymerization of carbon monoxide (CO and styrene (ST catalyzed by o-phenylenediamine resin-supported palladium acetate. Effects of each catalytic system component such as 2,2’-bipyridine, 1,4-quinone and p-toluene-sulphonate on the copolymerization were investigated. The resin-supported catalyst and the copolymerization product were characterized by infrared spectroscopy (IR, differential scanning calorimetry (DSC, thermogravimetry (TG, X-ray photoelectron spectroscopy (XPS, Scanning Electron Microscopy (SEM. Results indicated that the resin-supported catalyst has excellent catalytic property. Furthermore, partial catalytic activity was maintained after the catalyst was used for five times.

  2. An investigation on thermal decomposition of DNTF-CMDB propellants

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Wei; Wang, Jiangning; Ren, Xiaoning; Zhang, Laying; Zhou, Yanshui [Xi' an Modern Chemistry Research Institute, Xi' an 710065 (China)

    2007-12-15

    The thermal decomposition of DNTF-CMDB propellants was investigated by pressure differential scanning calorimetry (PDSC) and thermogravimetry (TG). The results show that there is only one decomposition peak on DSC curves, because the decomposition peak of DNTF cannot be separated from that of the NC/NG binder. The decomposition of DNTF can be obviously accelerated by the decomposition products of the NC/NG binder. The kinetic parameters of thermal decompositions for four DNTF-CMDB propellants at 6 MPa were obtained by the Kissinger method. It is found that the reaction rate decreases with increasing content of DNTF. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  3. Estudo da decomposição térmica de propelente sólido compósito de baixa emissão de fumaça Study of thermal decomposition of a smokelles propellant

    Directory of Open Access Journals (Sweden)

    Jony Andrade

    2008-01-01

    Full Text Available The thermal decomposition of hydroxyl-terminated polybutadiene (HTPB/ammonium nitrate (AN based propellants, so called smokeless formulations, and raw materials were investigated by differential scanning calorimetry (DSC and thermogravimetry (TG. The thermoanalytical profile of different components and of propellant were evaluated and the Arrhenius parameters for the thermal decomposition of the propellant sample were determined by the Ozawa method. The kinetic parameters of the thermal decomposition of propellant samples were determined by DSC measurements. The values obtained for activation energy (Ea and pre-exponential factor were 163 kJ mol-1 and 1.94x10(6 min-1.

  4. Mechanistic and Kinetic Analysis of Na2SO4-Modified Laterite Decomposition by Thermogravimetry Coupled with Mass Spectrometry.

    Directory of Open Access Journals (Sweden)

    Song Yang

    Full Text Available Nickel laterites cannot be effectively used in physical methods because of their poor crystallinity and fine grain size. Na2SO4 is the most efficient additive for grade enrichment and Ni recovery. However, how Na2SO4 affects the selective reduction of laterite ores has not been clearly investigated. This study investigated the decomposition of laterite with and without the addition of Na2SO4 in an argon atmosphere using thermogravimetry coupled with mass spectrometry (TG-MS. Approximately 25 mg of samples with 20 wt% Na2SO4 was pyrolyzed under a 100 ml/min Ar flow at a heating rate of 10°C/min from room temperature to 1300°C. The kinetic study was based on derivative thermogravimetric (DTG curves. The evolution of the pyrolysis gas composition was detected by mass spectrometry, and the decomposition products were analyzed by X-ray diffraction (XRD. The decomposition behavior of laterite with the addition of Na2SO4 was similar to that of pure laterite below 800°C during the first three stages. However, in the fourth stage, the dolomite decomposed at 897°C, which is approximately 200°C lower than the decomposition of pure laterite. In the last stage, the laterite decomposed and emitted SO2 in the presence of Na2SO4 with an activation energy of 91.37 kJ/mol. The decomposition of laterite with and without the addition of Na2SO4 can be described by one first-order reaction. Moreover, the use of Na2SO4 as the modification agent can reduce the activation energy of laterite decomposition; thus, the reaction rate can be accelerated, and the reaction temperature can be markedly reduced.

  5. Influence of metal additives on pyrolysis behavior of bituminous coal by TG-FTIR analysis

    Energy Technology Data Exchange (ETDEWEB)

    Su, Wenjuan; Fang, Mengxiang; Cen, Jianmeng; Li, Chao; Luo, Zhongyang; Cen, Kefa [Zhejiang Univ., Hangzhou (China). State Key Lab. of Clean Energy Utilization

    2013-07-01

    To study the catalytic effects of alkali, alkaline earth and transition metal additives on coal pyrolysis behavior, bituminous coal loaded NaCl, KCl, CaCl{sub 2}, MgCl{sub 2}, FeCl{sub 3} and NiCl{sub 2} was respectively investigated using Thermogravimetry and Fourier Transform Infrared Spectroscopy (TG-FTIR). Results indicated that the maximum mass loss rate decreased under the metal additives in the primary pyrolysis stage. The total mass loss of pyrolysis was reduced in metals catalyzed pyrolysis except for Na loaded sample. Kinetic analysis was taken for all samples adopting the method of Coats-Redfern. Activation energy of raw coal in the primary pyrolysis stage was 92.15vkJ.mol{sup -1}, which was lowered to 44.59-73.42 kJ.mol{sup -1} under metal additives. The orders of catalytic effect for this bituminous coal were Mg > Fe > Ca > Ni > K > Na according to their activation energies. Several investigated volatiles including CH{sub 4}, CO{sub 2}, CO, toluene, phenol and formic acid were identified from FTIR spectra. The yields of CH{sub 4}, CO{sub 2}, toluene, phenol and formic acid were decreased, but the evolution of CO was increased. The presence of metals in the coal samples have been involved in a repeated bond-forming and bond-breaking process, which greatly hindered the release of tars during pyrolysis as the tar precursors were connected to coal/char matrix and were thermally cracked, becoming a part of char.

  6. The Decompositioning of Volatile-Matter of Tanjung Enim Coal by using Thermogravimetry Analyzer (TGA

    Directory of Open Access Journals (Sweden)

    Nukman Nukman

    2010-10-01

    Full Text Available Coal is a nature material which a kind of energy source. The decompotition of coal could analyze by heat treated using thermogravimetry analyzer. The decomposition of the volatile matter for three kinds of Tanjung Enim coal could be known. The value of activation energy that be found diference, then for Semi Anthracite, Bitumonius and Sub Bituminous Coal, the initial temperatures are 60.8 oC, 70.7 oC, 97.8oC, and the last temperatures are 893.8 oC, 832 oC, 584.6oC.

  7. IMRT Commissioning: application of the AAPM's TG-119; Comissionamento de IMRT: aplicacao do TG-119 da AAPM

    Energy Technology Data Exchange (ETDEWEB)

    Zeppellini, Caroline; Furnari, Laura, E-mail: laurafurnari@hotmail.com [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Fac. de Medicina. Inst. de Radiologia

    2013-08-15

    In order to verify the commissioning of the planning of intensity-modulated radiation therapy system (IMRT), the TG-119 of the American Association of Physicists in Medicine (AAPM) was applied. Using pre defined targets and normal structures, plans were realized, absolute and relative dose were measured with an ionizing chamber and films, and the results were compared with planned values. The maximum deviation of the measurements with the ionization chamber was 3,6%, but, in the total eleven measurements, only two were bigger than the tolerance limit of 3%, recommended by TG-119. The number of points which passed criteria gamma 3% to 3 mm ranged between 96.36% and 99.92%, all measurements were within the recommended 95%. The confidence limits found for both film and for chamber were lower than those achieved in the TG-119. Our results showed a good concordance with TG-119, what means that the system is adequate for clinical applications. (author)

  8. Transglutaminase (TG) involvement in early embryogenesis

    International Nuclear Information System (INIS)

    Maccioni, R.B.; Arechaga, J.

    1986-01-01

    Transglutaminase (TG) has been examined in different stages of preimplantation mouse embryogenesis. The specific activity of this enzyme in the soluble cellular fraction increases 2-fold from 2-cell embryos to 8-cell morulae and 4-fold from 2-cell embryos to blastocyst. The same developmental profile was seen when either N,N-dimethylcasein or endogenous substrates were used in the TG assay. Using high-speed supernatants from different stage embryos as a source of enzyme and [ 3 H]putrescine as acyl acceptor, the major acyl donor components were tubulin and a high molecular weight (HMW) cross-linkage product, as assessed by electrophoresis and immunoblotting. When either assembled or monomeric cytoskeleton proteins were compared as subtrates, microtubules were the best acyl donors. These studies indicate that TG activity is modulated during the changing demands of blastomeres for microtubule cytoskeleton in early embryogenesis

  9. A poliomyelitis model through mucosal infection in transgenic mice bearing human poliovirus receptor, TgPVR21

    International Nuclear Information System (INIS)

    Nagata, Noriyo; Iwasaki, Takuya; Ami, Yasushi; Sato, Yuko; Hatano, Ikuyoshi; Harashima, Ayako; Suzaki, Yuriko; Yoshii, Takao; Hashikawa, Tsutomu; Sata, Tetsutaro; Horiuchi, Yoshinobu; Koike, Satoshi; Kurata, Takeshi; Nomoto, Akio

    2004-01-01

    Transgenic mice bearing the human poliovirus receptor (TgPVR) are less susceptible to oral inoculation, although they are susceptible to parenteral inoculation. We investigated the susceptibility of TgPVR 21 line [Arch. Virol. 130 (1994) 351] to poliovirus through various mucosal routes. Intranasal inoculation of a neurovirulent Mahoney strain (OM1) caused flaccid paralysis with viral replication in the central nervous system at a dose of 10 6 cell culture infectious dose (CCID 50 ), in contrast, no paralysis following oral or intragastric inoculation of the same dose. Intranasal inoculation of a vaccine strain, Sabin 1, at 10 6 CCID 50 , resulted in no paralysis. Initial replication of poliovirus in the nasal cavity was confirmed by virus isolation and detection of negative-stranded replicative intermediates by RT-PCR and viral antigens using a high-sensitive immunohistochemistry and genome/transcripts by in situ hybridization. Poliovirus-specific IgG antibodies were elevated in the sera of surviving TgPVR21. This model can be used as a mucosal infection model and for differentiation of neurovirulent and attenuated poliovirus strains

  10. Non-shoring construction for T/G pedestal beams

    International Nuclear Information System (INIS)

    Abe, T.

    1992-01-01

    The T/G pedestal construction work has been the critical path within the T/B construction work of BWR type nuclear power plant. In order to meet the requirement of shortening the construction period and improved in safety on a Turbine Building (T/B) construction work, Non-soring construction for T/G Pedestal Beams was developed. By applying this method to T/G pedestal construction work, we succeeded in shortening the T/B construction period and improvement in safety significantly. (author)

  11. Investigation on caloric requirement of biomass pyrolysis using TG-DSC analyzer

    Energy Technology Data Exchange (ETDEWEB)

    He Fang [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)]. E-mail: hf@sdut.edu.cn; Yi Weiming [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China); Bai Xueyuan [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)

    2006-09-15

    The caloric requirement of biomass pyrolysis has an important influence on the course of the thermal conversion. However, precise data are difficult to achieve by the current calculation method because of the complexity of the process. A new method for achieving the caloric requirement of the process by integrating the differential scanning calorimetry (DSC) curves was proposed after the simultaneous thermal analyzer (TG-DSC) and DSC curves were investigated. Experiments were conducted for wheat straw, cotton stalk, pine and peanut shell on a Netsch STA 449C analyzer. Powder samples were put into a platinum crucible with a lid on a high accuracy DSC-cp sample holder in the furnace and then heated from ambient temperature up to the maximum temperature of 973 K at the heating rate of 10 K/min in the analyzer. The product gases were swept away by 25 ml/min nitrogen. Mass changes (TG) and calorimetric effects (DSC) were recorded and analyzed. The process was investigated in detail through comparison of the DTG (differential thermogravimetric) and DSC curves of wheat straw. After the water influence in the DSC was eliminated, the relationship of the caloric requirement with the temperature of the aforementioned dry biomass was obtained by integrating the DSC curve. The results showed that 523 kJ, 459 kJ, 646 kJ and 385 kJ were required, respectively, to increase the temperature of 1 kg of dried wheat straw, cotton stalk, pine and peanut from 303 K to 673 K.

  12. Thermochemical study of 2,4-, 2,6- and 3,4-dihydroxybenzoic acids in the liquid phase using a TG apparatus

    International Nuclear Information System (INIS)

    Vecchio, Stefano; Brunetti, Bruno

    2011-01-01

    Research highlights: → Vapor pressures of solid and liquid 2,4- 2,6- and 3,4-dihydroxybenzoic acids, that don't decompose appreciably in the temperature range considered, were determined by torsion-effusion technique and thermogravimetry, respectively. → Agreement between the experimental sublimation vapor pressures and literature data recently published is good for all the three isomers. → From the temperature dependence of vapor pressure the molar enthalpies of sublimation and vaporization were determined at the middle of the respective experimental temperature intervals. → For validation of TG pressure data, the TG vapor pressures of solid ferrocene and 1,2-dihydroxybenzoic acid were successfully compared with the corresponding literature values. → The following increasing-order of volatility can be established: 2,6-dihydroxybenzoic acid l g H m o ( ) were determined, respectively, at the middle of the respective temperature intervals. The melting temperatures and the molar enthalpies of fusion of these compounds were measured by d.s.c. The vapor pressures of these compounds in the solid state, measured by torsion-effusion technique, were compared with recently published data, while the corresponding molar sublimation enthalpies were determined. In order to validate the vapor pressure results determined by TG, the experimental vapor pressure data regarding solid ferrocene and 1,2-dihydroxybenzoic acid were successfully compared with literature values in the range 20-200 Pa. In addition, the experimental molar enthalpies of fusion were compared with those calculated by subtracting the molar vaporization enthalpies to the sublimation ones, both adjusted to their respective melting temperatures. Finally, the standard (p o = 0.1 MPa) molar enthalpies, entropies and Gibbs energies of sublimation, corrected at the reference temperature of 298.15 K, have been calculated using the estimated heat capacity differences between gas and liquid for vaporization

  13. Effect of layered silicate content on the morphology and thermal properties of Poly(vinyl alcohol) films; Efeito do teor de silicato em camadas na morfologia e propriedades termicas de filmes de poli(alcool vinilico)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jessica R.M.B. da; Santos, Barbara F.F. dos; Leite, Itamara F., E-mail: jraquell@homail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Centro de Tecnologia. Departamento de Engenharia de Materiais

    2015-07-01

    This study aims to evaluate the effect of layered silicate content on the morphology and thermal properties of PVA films. The PVA/layered silicate (AN) films were prepared by intercalation solution, using 1 to 2% of bentonite with respect to the PVA total weight. Then the films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC). Results of the FTIR revealed interaction between the functional groups of the PVA and the layered silicate. The XRD analysis showed that nanocomposites with intercalated and partially exfoliated morphology were obtained. The results of TG showed that the nanocomposite PVA/2%AN showed higher thermal stability compared to PVA/1%AN. The DSC results showed that the addition of AN to the PVA did not affect crystallization rate, as well as promoted a reduction in glass transition temperature and melting of the PVA. (author)

  14. Effect of layered silicate content on the morphology and thermal properties of Poly(vinyl alcohol) films

    International Nuclear Information System (INIS)

    Silva, Jessica R.M.B. da; Santos, Barbara F.F. dos; Leite, Itamara F.

    2015-01-01

    This study aims to evaluate the effect of layered silicate content on the morphology and thermal properties of PVA films. The PVA/layered silicate (AN) films were prepared by intercalation solution, using 1 to 2% of bentonite with respect to the PVA total weight. Then the films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC). Results of the FTIR revealed interaction between the functional groups of the PVA and the layered silicate. The XRD analysis showed that nanocomposites with intercalated and partially exfoliated morphology were obtained. The results of TG showed that the nanocomposite PVA/2%AN showed higher thermal stability compared to PVA/1%AN. The DSC results showed that the addition of AN to the PVA did not affect crystallization rate, as well as promoted a reduction in glass transition temperature and melting of the PVA. (author)

  15. The High Temperature Resistivity of Ba2YCu3O7-x

    Science.gov (United States)

    Xingkui, Zhang; Shining, Zhu; Hao, Wang; Shiyuan, Zhang; Su, Ye; Ningshen, Zhou; Ziran, Xu

    The high temperature resistivity (ρ), thermogravimetry (TG) and derivative thermogravimetry (DTG) have been used to characterize superconductor Ba2YCu3O7-x (BYCO) in O2, air and N2. The resistivity is linear from room temperature to 350°C and then deviate from linearity with oxygen evolution, the derivative of resistivity dρ/dT increases abruptly near orthorhombic to tetragonal phase transition. These phenomena can give good explanations for a two-band Drude model.

  16. Long term aging of selenide glasses: evidence of sub-Tg endotherms and pre-Tg exotherms

    Science.gov (United States)

    Chen, Ping; Boolchand, P.; Georgiev, D. G.

    2010-02-01

    Long term aging, extending from months to several years, is studied on several families of chalcogenide glasses including the Ge-Se, As-Se, and Ge-As-Se systems. Special attention is given to the As-Se binary, a system that displays a rich variety of aging behavior intimately tied to sample synthesis conditions and the ambient environment in which samples are aged. Calorimetric (modulated DSC) and Raman scattering experiments are undertaken. Our results show all samples display a sub-Tg endotherm typically 10-70 °C below Tg in glassy networks possessing a mean coordination number r in the 2.25 < r < 2.45 range. Two sets of AsxSe100-x samples aged for eight years were compared, set A consisted of slow cooled samples aged in the dark, and set B consisted of melt-quenched samples aged at laboratory environment. Samples of set B in the As concentration range, 35% < x < 60%, display a pre-Tg exotherm, but the feature is not observed in samples of set A. The aging behavior of set A presumably represents intrinsic aging in these glasses, while that of set B is extrinsic due to the presence of light. The reversibility window persists in both sets of samples, but is less well defined in set B. These findings contrast with a recent study by Golovchak et al (2008 Phys. Rev. B 78 014202), which finds the onset of the reversibility window moved up to the stoichiometric composition (x = 40%). Here we show that the up-shifted window is better understood as resulting due to demixing of As4Se4 and As4Se3 molecules from the backbone, i.e., nanoscale phase separation (NSPS). We attribute sub-Tg endotherms to compaction of the flexible part of the networks upon long term aging, while the pre-Tg exotherm is to NSPS. The narrowing and sharpening of the reversibility window upon aging is interpreted as the slow 'self-organizing' stress relaxation of the phases just outside the intermediate phase, which itself is stress free and displays little aging.

  17. Comparative study of organovermiculites using natural and expanded vermiculite; Estudo comparativo de organovermiculitas utilizando vermiculita natural e expandida

    Energy Technology Data Exchange (ETDEWEB)

    Andrea, L.S.; Hudson, A.B.; Francisco, K.S.; Romualdo, R.M.; Gelmires, A.N.; Lisiane, N.L.S., E-mail: dea_lopes@hotmail.com [Universidade Federal de Campina Grande (UFCG), PB (Brazil). Departamento de Engenharia de Materiais

    2012-07-01

    Organovermiculites were obtained using vermiculite clay in its natural state and expanded in order to use these new materials in the adsorption of organic contaminants from water. Analysis by X-ray diffraction, infrared spectroscopy (IR), thermogravimetry (TG) and differential thermal analysis (DTA) were performed to obtain confirmation of these organovermiculites. Foster swelling and sorption tests were used to test the compatibility between the treated clay and organic solvents. The organophilization process has provided an increase in basal distance of vermiculite and it was observed an expressive increase in distance between the clay layers. The organovermiculite showed adsorption capacity by organic solvents tested, the best results were observed for diesel oil. (author)

  18. Comparative study of organovermiculites using natural and expanded vermiculite

    International Nuclear Information System (INIS)

    Andrea, L.S.; Hudson, A.B.; Francisco, K.S.; Romualdo, R.M.; Gelmires, A.N.; Lisiane, N.L.S.

    2012-01-01

    Organovermiculites were obtained using vermiculite clay in its natural state and expanded in order to use these new materials in the adsorption of organic contaminants from water. Analysis by X-ray diffraction, infrared spectroscopy (IR), thermogravimetry (TG) and differential thermal analysis (DTA) were performed to obtain confirmation of these organovermiculites. Foster swelling and sorption tests were used to test the compatibility between the treated clay and organic solvents. The organophilization process has provided an increase in basal distance of vermiculite and it was observed an expressive increase in distance between the clay layers. The organovermiculite showed adsorption capacity by organic solvents tested, the best results were observed for diesel oil. (author)

  19. TG Grammar's Implications for the Foreign Language Teaching

    Institute of Scientific and Technical Information of China (English)

    殷彩

    2009-01-01

    Chomsky's Transformational-Generative (TG) grammar is another revolution to linguistics after Saussure's strueturalism, and it plays an important role in the modem linguistics. Introducing the research perspective and method of TG grammar, this paper analyses its implications for the foreign language teaching.

  20. Effect of temperature on studtite stability: Thermogravimetry and differential scanning calorimetry investigations

    International Nuclear Information System (INIS)

    Rey, A.; Casas, I.; Gimenez, J.; Quinones, J.; Pablo, J. de

    2009-01-01

    The main objective of this work is the study of the influence of temperature on the stability of the uranyl peroxide tetrahydrate (UO 2 O 2 . 4H 2 O) studtite, which may form on the spent nuclear fuel surface as a secondary solid phase. Preliminary results on the synthesis of studtite in the laboratory at different temperatures have shown that the solid phases formed when mixing hydrogen peroxide and uranyl nitrate depends on temperature. Studtite is obtained at 298 K, meta-studtite (UO 2 O 2 . 2H 2 O) at 373 K, and meta-schoepite (UO 3 . nH 2 O, with n 3 O 8 . By means of the differential scanning calorimetry the molar enthalpies of the transformations occurring at 403 and 504 K have been determined to be -42 ± 10 and -46 ± 2 kJ mol -1 , respectively

  1. Gamma irradiation effects on the thermal, optical and structural properties of Cr-39 nuclear track detector

    International Nuclear Information System (INIS)

    Nouh, S.A.; Said, A.F.; Atta, M.R.; EL-Mellegy, W.M.; EL-Meniawi, S.

    2006-01-01

    A study of the effect of gamma irradiation on the thermal, optical and structural properties of CR-39 diglycol carbonate solid state nuclear track detector (SSNTD) has been carried out. Samples from CR-39 polymer were irradiated with gamma doses at levels between 20 and 300 KGy. Non-isothermal studies were carried out using thermo-gravimetry (TG), differential thermo-gravimetry (DTG) and differential thermal analysis (DTA) to obtain the activation energy of decomposition and the transition temperatures for the non-irradiated and irradiated CR-39 samples. In addition, optical and structural property studies were performed on non-irradiated and irradiated CR-39 samples using refractive index and X-ray diffraction measurements. The variation of onset temperature of decomposition (To) thermal activation energy of decomposition (Ea) melting temperature (Tm) refractive index (n) and the mass fraction of the amorphous phase with the gamma dose were studied. It was found that many changes in the thermal, optical and structural properties of the CR-39 polymer could be produced by gamma irradiation via the degradation and cross linking mechanisms. Also, the gamma dose gave an advantage for increasing the correlation between the thermal stability of CR-39 polymer and the bond formation created by the ionizing effect of gamma radiation

  2. Bio-based polyurethane composite foams with inorganic fillers studied by thermogravimetry

    International Nuclear Information System (INIS)

    Hatakeyema, Hyoe; Tanamachi, Noriko; Matsumura, Hiroshi; Hirose, Shigeo; Hatakeyama, Tatsuko

    2005-01-01

    Bio-based polyurethane (PU) composite foams filled with various inorganic fillers, such as barium sulfate (BaSO 4 ), calcium carbonate (CaCO 3 ) and talc were prepared using polyols, such as diethylene glycol, triethylene glycol and polyethylene glycol (molecular weight ca. 200) containing molasses and lignin. Reactive hydroxyl groups in plant components and above polyols were used as reaction sites. Morphological observation of fracture surface of composites was carried out by scanning electron microscopy. Thermal properties of bio-based PU composites were examined by thermogravimetry. It was found that the above composites decompose in two stages reflecting decomposition of organic components. Decomposition temperature increased with increasing filler content, when plant components were homogenously mixed with inorganic fillers. Activation energy calculated by Ozawa-Wall-Flynn method was ca. 150 kJ mol -1 . The durability of composites was predicted using kinetic data. Calculated values indicate that composites with fillers are more durable than that of those without fillers at a moderate temperature region

  3. Fabrication and Characteristics of Macroporous TiO2 Photocatalyst

    Directory of Open Access Journals (Sweden)

    Guiyun Yi

    2014-01-01

    Full Text Available Macroporous TiO2 photocatalyst was synthesized by a facile nanocasting method using polystyrene (PS spherical particles as the hard template. The synthesized photocatalyst was characterized by transmission electron microscope (TEM, scanning electron microscopy (SEM, thermogravimetry-differential thermogravimetry (TG-DTG, X-ray diffraction (XRD, and N2-sorption. TEM, SEM, and XRD characterizations confirmed that the macroporous TiO2 photocatalyst is composed of anatase phase. The high specific surface area of 87.85 m2/g can be achieved according to the N2-sorption analysis. Rhodamine B (RhB was chosen as probe molecule to evaluate the photocatalytic activity of the TiO2 catalysts. Compared with the TiO2 materials synthesized in the absence of PS spherical template, the macroporous TiO2 photocatalyst sintered at 500°C exhibits much higher activity on the degradation of RhB under the UV irradiation, which can be assigned to the well-structured macroporosity. The macroporous TiO2 material presents great potential in the fields of environmental remediation and energy conversion and storage.

  4. Tissue transglutaminase contributes to the all-trans-retinoic acid-induced differentiation syndrome phenotype in the NB4 model of acute promyelocytic leukemia.

    Science.gov (United States)

    Csomós, Krisztián; Német, István; Fésüs, László; Balajthy, Zoltán

    2010-11-11

    Treatment of acute promyelocytic leukemia (APL) with all-trans-retinoic acid (ATRA) results in terminal differentiation of leukemic cells toward neutrophil granulocytes. Administration of ATRA leads to massive changes in gene expression, including down-regulation of cell proliferation-related genes and induction of genes involved in immune function. One of the most induced genes in APL NB4 cells is transglutaminase 2 (TG2). RNA interference-mediated stable silencing of TG2 in NB4 cells (TG2-KD NB4) coupled with whole genome microarray analysis revealed that TG2 is involved in the expression of a large number of ATRA-regulated genes. The affected genes participate in granulocyte functions, and their silencing lead to reduced adhesive, migratory, and phagocytic capacity of neutrophils and less superoxide production. The expression of genes related to cell-cycle control also changed, suggesting that TG2 regulates myeloid cell differentiation. CC chemokines CCL2, CCL3, CCL22, CCL24, and cytokines IL1B and IL8 involved in the development of differentiation syndrome are expressed at significantly lower level in TG2-KD NB4 than in wild-type NB4 cells upon ATRA treatment. Based on our results, we propose that reduced expression of TG2 in differentiating APL cells may suppress effector functions of neutrophil granulocytes and attenuate the ATRA-induced inflammatory phenotype of differentiation syndrome.

  5. High Tg and fast curing epoxy-based anisotropic conductive paste for electronic packaging

    Science.gov (United States)

    Keeratitham, Waralee; Somwangthanaroj, Anongnat

    2016-03-01

    Herein, our main objective is to prepare the fast curing epoxy system with high glass transition temperature (Tg) by incorporating the multifunctional epoxy resin into the mixture of diglycidyl ether of bisphenol A (DGEBA) as a major epoxy component and aromatic diamine as a hardener. Furthermore, the curing behavior as well as thermal and thermomechanical properties were investigated by differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA). It was found that Tg obtained from tan δ of DGEBA/aromatic diamine system increased from 100 °C to 205 °C with the presence of 30 percentage by weight of multifunctional epoxy resin. Additionally, the isothermal DSC results showed that the multifunctional epoxy resin can accelerate the curing reaction of DGEBA/aromatic diamine system. Namely, a high degree of curing (˜90%) was achieved after a few minutes of curing at low temperature of 130 °C, owing to a large number of epoxy ring of multifunctional epoxy resin towards the active hydrogen atoms of aromatic diamine.

  6. Tissue-transglutaminase contributes to neutrophil granulocyte differentiation and functions.

    Science.gov (United States)

    Balajthy, Zoltán; Csomós, Krisztián; Vámosi, György; Szántó, Attila; Lanotte, Michel; Fésüs, László

    2006-09-15

    Promyelocytic NB4 leukemia cells undergo differentiation to granulocytes following retinoic acid treatment. Here we report that tissue transglutaminase (TG2), a protein cross-linking enzyme, was induced, then partially translocated into the nucleus, and became strongly associated with the chromatin during the differentiation process. The transglutaminase-catalyzed cross-link content of both the cytosolic and the nuclear protein fractions increased while NB4 cells underwent cellular maturation. Inhibition of cross-linking activity of TG2 by monodansylcadaverin in these cells led to diminished nitroblue tetrazolium (NBT) positivity, production of less superoxide anion, and decreased expression of GP91PHOX, the membrane-associated subunit of NADPH oxidase. Neutrophils isolated from TG2(-/-) mice showed diminished NBT reduction capacity, reduced superoxide anion formation, and down-regulation of the gp91phox subunit of NADPH oxidase, compared with wild-type cells. It was also observed that TG2(-/-) mice exhibited increased neutrophil phagocytic activity, but had attenuated neutrophil chemotaxis and impaired neutrophil extravasation with higher neutrophil counts in their circulation during yeast extract-induced peritonitis. These results clearly suggest that TG2 may modulate the expression of genes related to neutrophil functions and is involved in several intracellular and extracellular functions of extravasating neutrophil.

  7. Study of the Thermal Polymerization of Linseed and Passion Fruit Oils

    Science.gov (United States)

    Lopes, R. V. V.; Loureiro, N. P. D.; Fonseca, P. S.; Macedo, J. L.; Santos, M. L.; Sales, M. J.

    2008-08-01

    Researches involving ecofriendliness materials are growing up, as well as, a current interest in developing materials from inexpensive and renewable resources. Vegetable oils show a number of excellent properties, which could be utilized to produce valuable polymeric materials. In this work is described the synthesis of polymeric materials from linseed oil (Linum usitatissimum L.) and passion fruit oil (Passiflora edulis) and their characterization by thermogravimetry (TG), differential scanning calorimetry (DSC) and Raman spectroscopy. The TG curve shows that those polymeric materials present two stages of decomposition. DSC plots of the vegetable oils showed some endothermic and exothermic transitions which are not present in the DSC curves corresponding to oil-based polymers. The Raman spectra of the polymers indicate declining of absorbance in the region of C = C stretching (˜1600 cm-1). This absorption was used to estimate the degree of polymerization (79% and 67.5% for linseed and passion fruit oils, respectively)

  8. Effect of calcination temperature on the photocatalytic activity of TiO2 powders prepared by co-precipitation of TiCl3

    International Nuclear Information System (INIS)

    Yudoyono, Gatut; Ichzan, Nur; Zharvan, Vicran; Daniyati, Rizqa; Santoso, Hadi; Indarto, Bachtera; Pramono, Yono Hadi; Zainuri, Mochamad; Darminto

    2016-01-01

    The adsorption of basic dye methylene blue (MB) onto titanium dioxide (titania) powder that were prepared by coprecipitation method of TiCl 3 and NH 4 OH as iniatial material with different calcination temperature was studied to examine the photocatalytic activity. Synthesis process carried out by the solution pH was adjusted to be 8. Effect of calcination temperature on the titania powder were characterized with Differential Scanning Calorimetry/Thermogravimetry (DSC/TG), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The result of TG and XRD showed that the NH 4 Cl decomposed between 235-372°C. The XRD result showed that the anatase TiO 2 only contained a single phase when the calcination temperature of the precursor at 800°C, and over which it began to grow rutile phase. The influence of synthesis condition on the photocatalytic activity of TiO 2 powder was determined by the photodegradation of MB dye under UV light.

  9. Kinetics of thermal decomposition of ammonium perchlorate with nanocrystals of binary transition metal ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Gurdip; Kapoor, Inder Pal Singh; Dubey, Shalini [Department of Chemistry, D. D. U. Gorakhpur University, Gorakhpur (India); Siril, Prem Felix [Laboratoire de Chimie Physique (LCP), Universite de Paris Sud, Orsay (France)

    2009-02-15

    Binary transition metal ferrite (BTMF) nanocrystals of formula MFe{sub 2}O{sub 4}(M=Cu,Co,Ni) were prepared by the coprecipitation method and characterized by X-ray diffraction (XRD). XRD patterns gave average particle size by using Scherrer's equation for CuFe{sub 2}O{sub 4}(CuF), CoFe{sub 2}O{sub 4}(CoF), and NiFe{sub 2}O{sub 4} (NiF) as 39.9, 27.3, and 43.8 nm, respectively. The catalytic activity measurements on the thermal decomposition of ammonium perchlorate (AP) were carried out by using thermogravimetry (TG), differential thermal analysis (DTA), and ignition delay studies. Isothermal TG data up to a mass loss of 45% have been used to evaluate kinetic parameters by using model fitting as well as isoconversional method. The order of catalytic activity was found to be: CoFe{sub 2}O{sub 4}>NiFe{sub 2}O{sub 4}. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  10. Thermoanalytical, spectroscopic and DFT studies of heavy trivalent lanthanides and yttrium(III) with oxamate as ligand

    Energy Technology Data Exchange (ETDEWEB)

    Caires, Flavio Junior; Gaglieri, Caroline, E-mail: caires.flavio@fc.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Bauru, SP (Brazil). Faculdade de Ciencias; Nunes, Wilhan Donizete Goncalves; Nascimento, Andre Luiz Carneiro Soares do; Teixeira, Jose Augusto; Zangaro, Georgia Alvim Coelho; Treu-Filho, Oswaldo; Ionashiro, Massao [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Araraquara, SP (Brazil)

    2017-07-15

    Solid-state LnL{sub 3}∙nH{sub 2}O complexes, where Ln stands for trivalent lanthanides (Tb to Lu) or yttrium(III) and L is oxamate (NH{sub 2}COCO{sub 2}{sup -}), have been synthesized. The characterization of the complexes was performed by using elemental analysis (EA), complexometric titration with EDTA, thermoanalytical techniques such as simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), evolved gas analysis (TG-FTIR), infrared spectroscopy (IR) and powder X-ray diffraction (XRPD). The results provided information about thermal behavior, crystallinity, stoichiometry, coordination sites, as well as the products released during thermal degradation of the complexes studied. Theoretical calculation of yttrium oxamate, as representative of all complexes was performed using density functional theory (DFT) for studying the molecular structure and vibrational spectrum of the investigated molecule in the ground state. The optimized geometrical parameters and theoretical vibrational spectrum obtained by DFT calculations are in good agreement with the experimental results. (author)

  11. Model Analytical Development for Physical, Chemical, and Biological Characterization of Momordica charantia Vegetable Drug

    Science.gov (United States)

    Guimarães, Geovani Pereira; Santos, Ravely Lucena; Júnior, Fernando José de Lima Ramos; da Silva, Karla Monik Alves; de Souza, Fabio Santos

    2016-01-01

    Momordica charantia is a species cultivated throughout the world and widely used in folk medicine, and its medicinal benefits are well documented, especially its pharmacological properties, including antimicrobial activities. Analytical methods have been used to aid in the characterization of compounds derived from plant drug extracts and their products. This paper developed a methodological model to evaluate the integrity of the vegetable drug M. charantia in different particle sizes, using different analytical methods. M. charantia was collected in the semiarid region of Paraíba, Brazil. The herbal medicine raw material derived from the leaves and fruits in different particle sizes was analyzed using thermoanalytical techniques as thermogravimetry (TG) and differential thermal analysis (DTA), pyrolysis coupled to gas chromatography/mass spectrometry (PYR-GC/MS), and nuclear magnetic resonance (1H NMR), in addition to the determination of antimicrobial activity. The different particle surface area among the samples was differentiated by the techniques. DTA and TG were used for assessing thermal and kinetic parameters and PYR-GC/MS was used for degradation products chromatographic identification through the pyrograms. The infusions obtained from the fruit and leaves of Momordica charantia presented antimicrobial activity. PMID:27579215

  12. Preparation, characterization and catalytic effects of copper oxalate nanocrystals

    International Nuclear Information System (INIS)

    Singh, Gurdip; Kapoor, Inder Pal Singh; Dubey, Reena; Srivastava, Pratibha

    2012-01-01

    Graphical abstract: Prepared copper oxalate nanocrystals were characterized by FE-SEM and bright field TEM micrographs. Its catalytic activity was evaluated on the thermal decomposition of ammonium perchlorate using TG and TG-DSC techniques. Highlights: ► Preparation of nanocrystals (∼9.0 nm) of copper oxalate using Cu(NO 3 ) 2 ·2H 2 O, oxalic acid and acetone under thermal conditions. ► Method is simple and novel. ► Characterization using XRD, SEM, TEM, HRTEM and ED pattern. ► Catalytic activity of copper oxalate nanocrystals on AP thermal decomposition using thermal techniques (TG, TG-DSC and ignition delay). ► Kinetics of thermal decomposition of AP + CONs using isoconversional and model fitting kinetic approaches. - Abstract: Recent work has described the preparation and characterization of copper oxalate nanocrystals (CONs). It was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and electron diffraction pattern (ED). The catalytic activity of CONs on the thermal decomposition of ammonium perchlorate (AP) and composite solid propellants (CSPs) has been done by thermogravimetry (TG), differential scanning calorimetry (DSC) and ignition delay measurements. Burning rate of CSPs was also found to be enhanced in presence of copper oxalate nanocrystals. Kinetics of thermal decomposition of AP with and without CONs has also been investigated. The model free (isoconversional) and model-fitting kinetic approaches have been applied to data for isothermal TG decomposition.

  13. Measurements of Gasification Characteristics of Coal and Char in CO2-Rich Gas Flow by TG-DTA

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2013-01-01

    Full Text Available Pyrolysis, combustion, and gasification properties of pulverized coal and char in CO2-rich gas flow were investigated by using gravimetric-differential thermal analysis (TG-DTA with changing O2%, heating temperature gradient, and flow rate of CO2-rich gases provided. Together with TG-DTA, flue gas generated from the heated coal, such as CO, CO2, and hydrocarbons (HCs, was analyzed simultaneously on the heating process. The optimum O2% in CO2-rich gas for combustion and gasification of coal or char was discussed by analyzing flue gas with changing O2 from 0 to 5%. The experimental results indicate that O2% has an especially large effect on carbon oxidation at temperature less than 1100°C, and lower O2 concentration promotes gasification reaction by producing CO gas over 1100°C in temperature. The TG-DTA results with gas analyses have presented basic reference data that show the effects of O2 concentration and heating rate on coal physical and chemical behaviors for the expected technologies on coal gasification in CO2-rich gas and oxygen combustion and underground coal gasification.

  14. Investigation of thermodynamic properties of magnesium chloride amines by HPDSC and TG. For application in a high-lift high-temperature chemical heat pump

    NARCIS (Netherlands)

    Bevers, E.R.T.; Oonk, H.A.J.; Haije, W.G.; Ekeren, P.J. van

    2007-01-01

    The formation as well as the decomposition of magnesium chloride ammonia complexes was studied by high-pressure differential scanning calorimetry (HPDSC) and thermogravimetric analysis (TG). HPDSC runs were performed under constant ammonia pressure conditions to determine the transition temperatures

  15. A new VME timing module: TG8

    International Nuclear Information System (INIS)

    Beetham, C.G.; Daems, G.; Lewis, J.; Puccio, B.

    1992-01-01

    The two accelerator divisions of CERN, namely PS and SL, are defining a new common control system based on PC, VME and Workstations. This has provided an opportunity to review both central timing systems and to come up with common solutions. The result was, amongst others, the design of a unique timing module, called TG8. The TG8 is a multipurpose VME module, which receives messages distributed over a timing network. These messages include timing information, clock plus calendar and telegrams instructing the CERN accelerators on the characteristics of the next beam to be produced. The TG8 compares incoming messages with up to 256 programmed actions. An action consists of two parts, a trigger which matches an incoming message and what to do when the match occurs. The latter part may optionally create an output pulse on one of the eight output channels and/or a bus interrupt, both with programmable delay and telegram conditioning. (author)

  16. Study of the aluminothermic reduction of niobium pentoxide through thermal analysis experiments and high energy milling processing

    Directory of Open Access Journals (Sweden)

    Claudio Parra De Lazzari

    2007-06-01

    Full Text Available Aluminothermic reduction of niobium pentoxide was studied through thermal analysis techniques such as differential thermal analysis (DTA and thermogravimetry (TG as well as through high energy milling processing. Reactants mixtures were composed by powders of Nb2O5 and Al. In the case of DTA-TG experiments, different molar ratios Nb2O5:Al were heated in a dynamic atmosphere of synthetic air under controlled conditions. The high energy milling runs were carried out via SPEX vibratory mill under argon atmosphere and with milling power equal to 7:1 (ratio of mass of balls to mass of mixture with 10 pct excess of Al over the stoichiometric mass of aluminum necessary. In both kinds of experiments, X ray diffraction was used in order to identify the products of reaction. From DTA-TG experiments, it was possible to determine the experimental value of the enthalpy change (-595.9 kJ.mol-1, which is near to the theoretical one. From the milling experiments, it was possible to verify the possibility of the occurance of aluminothermic reducion of niobium pentoxide via this kind of processing.

  17. Thermal decomposition process of silver behenate

    International Nuclear Information System (INIS)

    Liu Xianhao; Lu Shuxia; Zhang Jingchang; Cao Weiliang

    2006-01-01

    The thermal decomposition processes of silver behenate have been studied by infrared spectroscopy (IR), X-ray diffraction (XRD), combined thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS), transmission electron microscopy (TEM) and UV-vis spectroscopy. The TG-DTA and the higher temperature IR and XRD measurements indicated that complicated structural changes took place while heating silver behenate, but there were two distinct thermal transitions. During the first transition at 138 deg. C, the alkyl chains of silver behenate were transformed from an ordered into a disordered state. During the second transition at about 231 deg. C, a structural change took place for silver behenate, which was the decomposition of silver behenate. The major products of the thermal decomposition of silver behenate were metallic silver and behenic acid. Upon heating up to 500 deg. C, the final product of the thermal decomposition was metallic silver. The combined TG-MS analysis showed that the gas products of the thermal decomposition of silver behenate were carbon dioxide, water, hydrogen, acetylene and some small molecule alkenes. TEM and UV-vis spectroscopy were used to investigate the process of the formation and growth of metallic silver nanoparticles

  18. Studies on the rare earth complexes with pyridine derivatives and their N-oxide(II) - Synthesis and properties of fluorescent solid complexes of samarium, europium, gadolium and terbium chlorides with 2,2'-bipyridine-N,N'-dioxide

    International Nuclear Information System (INIS)

    Minyu, T.; Ning, T.; Yingli, Z.; Jiyuan, B.

    1985-01-01

    The solid complexes of rare earth nitrates perchlorates and thiocyanates with 2,2'-bipyridine-N,N'-dioxide (bipyO/sub 2/) have been reported. However, the corresponding complexes of other rear earth chlorides have not been investigated except lanthanum, cerium and yttrium. As an extension of our previous work on the synthesis of complexes of praseodymium and neodymium chlorides wiht bipoyO/sub 2/, the authors have now prepared fluorescent solid complexes of samarium, europium, gadolium and terbium chlorides with biphyO/sub 2/, using methanol as a reaction medium. The new synthesized compounds have been identified by means of elemental analysis, infrared spectrometry, conductometry, differential thermal analysis (DTA), thermogravimetry (TG) and X-ray powder diffraction

  19. Thermal expansion properties of calcium aluminate hydrates

    International Nuclear Information System (INIS)

    Song, Tae Woong

    1986-01-01

    In order to eliminate the effect of impurities and aggregates on the thermomechanical properties of the various calcium aluminate hydrates, and to prepare clinkers in which all calcium aluminates are mixed homogeneously, chemically pure CaO and Al 2 O 3 were weighed, blended and heated in various conditions. After quantitative X-ray diffractometry(QXRD), the synthesized clinker was hydrated and cured under the conditions of 30 deg C, W/C=0.5, relative humidity> 90% respectively during 24 hours. And then differential thermal analysis(DTA), thermogravimetry(TG), micro calorimetry, thermomechanical analysis(TMA) and scanning electron microanalysis(SEM) were applied to examine the thermal properties of samples containing, calcium aluminate hydrates in various quantity. (Author)

  20. Preparation of 5-benzotriazolyl-4-hydroxy-3- sec-butylbenzenesulfonate anion-intercalated layered double hydroxide and its photostabilizing effect on polypropylene

    Science.gov (United States)

    Li, Dianqing; Tuo, Zhenjun; Evans, David G.; Duan, Xue

    2006-10-01

    An organic UV absorber has been intercalated into a layered double hydroxide (LDH) host by ion-exchange method using ZnAl-NO 3-LDH as a precursor with an aqueous solution of the sodium salt of 5-benzotriazolyl-4-hydroxy-3- sec-butylbenzenesulfonic acid (BZO). After intercalation of the UV absorber, the interlayer distance in the LDHs increases from 0.89 to 2.32 nm. Infrared spectra and thermogravimetry and differential thermal analysis (TG-DTA) curves reveal the presence of a complex system of supramolecular host-guest interactions. The thermostability of BZO is markedly enhanced by intercalation in the LDH host. ZnAl-BZO-LDHs/polypropylene composite materials exhibit excellent UV photostability.

  1. Combustion behaviour of Sydney and Bowen Basin coals determined by thermogravimetry

    Energy Technology Data Exchange (ETDEWEB)

    Benfell, K.E.; Beamish, B.B.; Rodgers, K.A.; Crosdale, P.J. [University of Auckland, Auckland (New Zealand). Department of Geology

    1996-08-01

    Assesses the suitability of thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis techniques to characterise the combustion behaviour of Sydney and Bowen basin coals. Results indicate that the thermogravimetric technique is suitable for characterising the effects of rank, maceral, sub-maceral and seam variations on the combustion behaviour of these coals. 6 refs., 6 figs., 2 tabs.

  2. Determinação dos teores de umidade e cinzas de amostras comerciais de guaraná utilizando métodos convencionais e análise térmica Determination of humidity and ash content of guarana commercial samples using conventional method and thermal analysis

    Directory of Open Access Journals (Sweden)

    Adriano Antunes de Souza Araújo

    2006-06-01

    Full Text Available Paullinia cupana Kunth, vegetal popularmente conhecido como guaraná, é uma planta da família Sapindaceae predominante na região amazônica. A baixa qualidade deste produto pode ser atribuída a espécies e variedades menos nobres, técnicas de colheita e/ou de processamento inadequado ou, ainda, devido à adição de substâncias que não fazem parte de sua composição natural. Neste trabalho objetivou-se avaliar, a partir da termogravimetria (TG/termogravimetria derivada (DTG e calorimetria exploratória diferencial (DSC, o comportamento térmico de amostras comerciais de guaraná em pó existentes no Brasil e estabelecer um estudo comparativo entre os métodos convencionais e termogravimétrico para determinação dos teores de umidade e cinzas. A similaridade entre os perfis das curvas TG/DTG e DSC indicam que não há diferenças entre as amostras. A utilização da TG mostrou que é possível reduzir o tempo de análise, utilizar menor quantidade de amostra, assim como, fazer a determinação simultânea dos teores de umidade e cinzas. Em relação ao método convencional, erros de análise inerentes à manipulação das amostras são minimizados. As técnicas termoanalíticas mostram-se como ferramentas potenciais para a obtenção de parâmetros tecnológicos, em controle de qualidade, torrefação e condições adequadas de armazenamento.Paullinia cupana Kunth a vegetable popularly known as guarana, belongs to the Sapindaceas plant family and is predominant in the Amazon region. The low quality of this product can be attributed to the species and less noble varieties, harvest techniques and/or inadequate processing or, yet due to addition of substances that are not included in its natural composition. The main goal of this work was to evaluate from thermogravimetry (TG/derivative thermogravimetry (DTG and differential scanning calorimetry (DSC, the thermal behavior of powdered guarana samples in the Brazilian market in order to

  3. Experimental and Numerical Investigation of Effect of Coal Rank on Burn-off Time in Pulverized Coal Combustion

    OpenAIRE

    Nozawa, Sohei; Wada, Nozomi; Matsushita, Yosuke; Yamamoto, Tsuyoshi; Omori, Motohira; Harada, Tatsuro

    2012-01-01

    Thermogravimetry (TG) for two different coal ranks, Loy Yang coal and Newlands coal, was carried out in an atmospheric air environment. Detailed parameters of the heterogeneous oxidation reaction for each coal rank were estimated by analyzing the TG results. Heat and mass transfer of a single pulverized coal particle that was heated at a constant temperature were numerically simulated. In this calculation, the decrease in the mass ratio caused by the oxidation reaction was considered. The num...

  4. Sustainable Blended Cements-Influences of Packing Density on Cement Paste Chemical Efficiency.

    Science.gov (United States)

    Knop, Yaniv; Peled, Alva

    2018-04-18

    This paper addresses the development of blended cements with reduced clinker amount by partial replacement of the clinker with more environmentally-friendly material (e.g., limestone powders). This development can lead to more sustainable cements with reduced greenhouse gas emission and energy consumption during their production. The reduced clicker content was based on improved particle packing density and surface area of the cement powder by using three different limestone particle diameters: smaller (7 µm, 3 µm) or larger (70 µm, 53 µm) than the clinker particles, or having a similar size (23 µm). The effects of the different limestone particle sizes on the chemical reactivity of the blended cement were studied by X-ray diffraction (XRD), thermogravimetry and differential thermogravimetry (TG/DTG), loss on ignition (LOI), isothermal calorimetry, and the water demand for reaching normal consistency. It was found that by blending the original cement with limestone, the hydration process and the reactivity of the limestone itself were increased by the increased surface area of the limestone particles. However, the carbonation reaction was decreased with the increased packing density of the blended cement with limestone, having various sizes.

  5. Investigation of dehydration reaction of BaCl2.2H2O and SrCl2.6H2O by thermal analysis under pressure

    International Nuclear Information System (INIS)

    Homma, Tsuneyuki; Yamada, Tetsuo

    1978-01-01

    The dehydration reactions of BaCl 2 .2H 2 O and SrCl 2 .6H 2 O were investigated by the techniques of thermal analysis, i.e. thermogravimetry (TG and DTG) and differential thermal analysis (DTA) under pressures of 1, 4, 10 and 40 atm. For BaCl 2 .2H 2 O, the DTA curves showed two peaks at 1 atm and three or four peaks at pressures above 4 atm, and the TG curves showed two steps over the range of 1 -- 10 atm and 3 steps at 40 atm. For SrCl 2 .6H 2 O, the DTA curves showed five peaks at respective pressure, and the TG curves showed three steps at 1 atm and two steps at pressures above 4 atm. As a common effect of pressure to the dehydration of these two salts, DTG peaks and some of DTA peaks shifted to higher temperatures with a increase in pressure, but a few peaks remained unshifted on DTA curves in spite of increasing pressure. The peaks which corresponded to these unshifted peaks on DTA curves were not observed on DTG curves. The unshifted peaks on DTA curves were attributed to the endothermic reaction accompanied by the dissociation of coordination water. The DTA and TG curves suggested that both salts formed the intermediate state between anhydrous and monohydrate states. (auth.)

  6. Vapor pressures and standard molar enthalpies, entropies and Gibbs energies of sublimation of two hexachloro herbicides using a TG unit

    International Nuclear Information System (INIS)

    Vecchio, Stefano

    2010-01-01

    The vapor pressures above the solid hexachlorobenzene (HCB) and above both the solid and liquid 1,2,3,4,5,6-hexachlorocyclohexane (lindane) were determined in the ranges 332-450 K and 347-429 K, respectively, by measuring the mass loss rates recorded by thermogravimetry under both isothermal and nonisothermal conditions. The results obtained were compared with those taken from literature. From the temperature dependence of vapor pressure derived by the experimental thermogravimetry data the molar enthalpies of sublimation Δ cr g H m o ( ) were selected for HCB and lindane as well as the molar enthalpy of vaporization Δ l g H m o ( ) for lindane only, at the middle of the respective temperature intervals. The melting temperatures and the molar enthalpies of fusion Δ cr l H m o (T fus ) of lindane were measured by differential scanning calorimetry. Finally, the standard molar enthalpies of sublimation Δ cr g H m o (298.15 K) were obtained for both chlorinated compounds at the reference temperature of 298.15 K using the Δ cr g H m o ( ), Δ l g H m o ( ) and Δ cr l H m o (T fus ) values, as well as the heat capacity differences between gas and liquid and the heat capacity differences between gas and solid, Δ l g C p,m o and Δ cr g C p,m o , respectively, both estimated by applying a group additivity procedure. Therefore, the averages of the standard (p o = 0.1 MPa) molar enthalpies, entropies and Gibbs energies of sublimation at 298.15 K, have been derived.

  7. TG/FT-IR characterization of additives typically employed in EPDM formulations

    Directory of Open Access Journals (Sweden)

    Natália Beck Sanches

    2015-06-01

    Full Text Available AbstractThermogravimetric analysis coupled to Fourier transform infrared spectroscopy (TG/FT-IR is a very popular technique for rubbers characterization. It involves analyses of the base polymer and additives. Ethylene–propylene–diene (EPDM rubbers are frequently investigated by TG/FT-IR; however, the focus has been the degradation temperature range of the polymer. In this study, unvulcanized and vulcanized EPDM rubber and its additives were investigated by TG/FT-IR, without solvent extraction, and in a wide temperature range. Initially, the additives were individually characterized. TG/FT-IR identified the characteristic groups of all the additives analyzed and distinguished them from each other. Afterwards, unvulcanized and vulcanized EPDM rubbers were investigated without prior extraction.TG/FT-IR detected absorptions due to the additives tetramethylthiuram monosulfide and 2-mercaptobenzothiazole. Both of these sulfur-containing additives were present in the EPDM formulation at concentrations of 0.7 phr (0.63 wt %. The TG/FT-IR technique had some limitations, because not all the additives in EPDM rubber were detected. Paraffin oil, stearic acid and 2,2,4-trimethyl-1,2-dihydroquinoline functional groups were not observed in either the unvulcanized or vulcanized EPDM. Nevertheless, in addition to the ability of this method to detect sulfur-containing groups, the lack of a pre-extraction reduces the time and effort required for additive analysis in rubbers.

  8. Thermogravimetric study of oxidation of a PdCr alloy used for high-temperature sensors

    Science.gov (United States)

    Boyd, Darwin L.; Zeller, Mary V.

    1994-01-01

    In this study, the oxidation of Pd-13 weight percent Cr, a candidate alloy for high-temperature strain gages, was investigated by thermogravimetry. Although the bulk alloy exhibits linear electrical resistivity versus temperature and stable resistivity at elevated temperatures, problems attributed to oxidation occur when this material is fabricated into strain gages. In this work, isothermal thermogravimetry (TG) was used to study the oxidation kinetics. Results indicate that the oxidation of Pd-13 weight percent Cr was approximately parabolic in time at 600 C but exhibited greater passivation from 700 to 900 C. At 1100 C, the oxidation rate again increased.

  9. TG-FTIR analysis of biomass pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Bassilakis, R.; Carangelo, R.M.; Wojtowicz, M.A. [Advanced Fuel Research Inc., Hartford, CT (United States)

    2001-10-09

    A great need exists for comprehensive biomass-pyrolysis models that could predict yields and evolution patterns of selected volatile products as a function of feedstock characteristics and process conditions. A thermogravimetric analyzer coupled with Fourier transform infrared analysis of evolving products (TG-FTIR) can provide useful input to such models in the form of kinetic information obtained under low heating rate conditions. In this work, robust TG-FTIR quantification routes were developed for infrared analysis of volatile products relevant to biomass pyrolysis. The analysis was applied to wheat straw, three types of tobacco (Burley, Oriental, and Bright) and three biomass model compounds (xylan, chlorogenic acid, and D-glucose). Product yields were compared with literature data, and species potentially quantifiable by FT-IR are reviewed. Product-evolution patterns are reported for all seven biomass samples. 41 refs., 7 figs., 2 tabs.

  10. Synthesis and characterization of nanocomposite powders of calcium phosphate/titanium oxide for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Delima, S.A.; Camargo, N.H.A.; Souza, J.C.P.; Gemelli, E., E-mail: sarahamindelima@hotmail.com, E-mail: dem2nhac@joinville.udesc.br, E-mail: souzajulio@joinville.udesc.br, E-mail: gemelli@joinville.udesc.br [Universidade do Estado de Santa Catarina (UDESC), Joinville, SC (Brazil). Centro de Ciencias Tecnologicas

    2009-07-01

    The nanostructured bioceramics of calcium phosphate are current themes of research and they are becoming important as bone matrix in regeneration of tissues in orthopedic and dental applications. Nanocomposite powders of calcium phosphate, reinforced with nanometric particles of titanium oxide, silica oxide and alumina oxid ealpha, are being widely studied because they offer new microstructures, nanostructures and interconnected microporosity with high superficial area of micropores that contribute to osteointegration and osteoinduction processes. This study is about the synthesis of nanocomposites powders of calcium phosphate reinforced with 1%, 2%, 3% and 5% in volume of titanium oxide and its characterization through the techniques of X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Differential Thermal Analysis (DTA), Thermogravimetry (TG) and Dilatometry. (author)

  11. Characterization of injected linear low density polyethylene (LLDPE) irradiated by gamma-ray

    International Nuclear Information System (INIS)

    Oliveira, Ana C.F.; Parra, Duclerc F.; Ferreto, Helio F.R.; Lugao, Ademar B.

    2013-01-01

    The aim of this paper is to investigate of gamma irradiation effects on linear low density polyethylene (LLDPE) injected. Polymers processed by gamma radiation have new physical-chemical and mechanical properties. The ionizing radiation promotes chain scission and creates free radicals which can recombine, providing their annihilation, for crosslinking or branching. The polymer was irradiated with a source of 60 Co at doses of 5, 10, 20, 50 or 100 kGy at about 5 kGy s -1 rate, at room temperature. The changes in molecular structure of LLDPE were evaluated using melt flow index, gel fraction, differential scanning calorimetry (DSC), fourier transform infrared spectroscopy (FT-IR) and thermogravimetry analysis (TG). The results showed that the properties depend on dose irradiation. (author)

  12. Fabrication and characterization of biomorphic 45S5 bioglass scaffold from sugarcane

    International Nuclear Information System (INIS)

    Qian Junmin; Kang Yahong; Wei Zilin; Zhang Wei

    2009-01-01

    A biomorphic 45S5 bioglass scaffold has been fabricated from natural plant sugarcane successfully by a novel biotemplating process. Scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetry and differential scanning calorimetry (TG-DSC) technologies were employed to characterize the morphology, phase and chemical composition of the products. Experimental results show that the as-fabricated 45S5 bioglass scaffold retained the microstructure of sugarcane very well, and consisted of major crystal phase Na 2 Ca 2 Si 3 O 9 of hexagonal system, secondary crystal phase orthorhombic NaCaPO 4 and amorphous glass. The biomorphic 45S5 bioglass scaffold may be a promising candidate scaffold for bone tissue engineering.

  13. Synthesis and characterization of nanocomposite powders of calcium phosphate/titanium oxide for biomedical applications

    International Nuclear Information System (INIS)

    Delima, S.A.; Camargo, N.H.A.; Souza, J.C.P.; Gemelli, E.

    2009-01-01

    The nanostructured bioceramics of calcium phosphate are current themes of research and they are becoming important as bone matrix in regeneration of tissues in orthopedic and dental applications. Nanocomposite powders of calcium phosphate, reinforced with nanometric particles of titanium oxide, silica oxide and alumina oxid ealpha, are being widely studied because they offer new microstructures, nanostructures and interconnected microporosity with high superficial area of micropores that contribute to osteointegration and osteoinduction processes. This study is about the synthesis of nanocomposites powders of calcium phosphate reinforced with 1%, 2%, 3% and 5% in volume of titanium oxide and its characterization through the techniques of X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Differential Thermal Analysis (DTA), Thermogravimetry (TG) and Dilatometry. (author)

  14. Role of Tulipa gesneriana TEOSINTE BRANCHED1 (TgTB1) in the control of axillary bud outgrowth in bulbs.

    Science.gov (United States)

    Moreno-Pachon, Natalia M; Mutimawurugo, Marie-Chantal; Heynen, Eveline; Sergeeva, Lidiya; Benders, Anne; Blilou, Ikram; Hilhorst, Henk W M; Immink, Richard G H

    2018-06-01

    Tulip vegetative reproduction. Tulips reproduce asexually by the outgrowth of their axillary meristems located in the axil of each bulb scale. The number of axillary meristems in one bulb is low, and not all of them grow out during the yearly growth cycle of the bulb. Since the degree of axillary bud outgrowth in tulip determines the success of their vegetative propagation, this study aimed at understanding the mechanism controlling the differential axillary bud activity. We used a combined physiological and "bottom-up" molecular approach to shed light on this process and found that first two inner located buds do not seem to experience dormancy during the growth cycle, while mid-located buds enter dormancy by the end of the growing season. Dormancy was assessed by weight increase and TgTB1 expression levels, a conserved TCP transcription factor and well-known master integrator of environmental and endogenous signals influencing axillary meristem outgrowth in plants. We showed that TgTB1 expression in tulip bulbs can be modulated by sucrose, cytokinin and strigolactone, just as it has been reported for other species. However, the limited growth of mid-located buds, even when their TgTB1 expression is downregulated, points at other factors, probably physical, inhibiting their growth. We conclude that the time of axillary bud initiation determines the degree of dormancy and the sink strength of the bud. Thus, development, apical dominance, sink strength, hormonal cross-talk, expression of TgTB1 and other possibly physical but unidentified players, all converge to determine the growth capacity of tulip axillary buds.

  15. FPGA Implementation of Burst-Mode Synchronization for SOQSPK-TG

    Science.gov (United States)

    2014-06-01

    is normalized to π. The proposed burst-mode architecture is written in VHDL and verified using Modelsim. The VHDL design is implemented on a Xilinx...Document Number: SET 2014-0043 412TW-PA-14298 FPGA Implementation of Burst-Mode Synchronization for SOQSPK-TG June 2014 Final Report Test...To) 9/11 -- 8/14 4. TITLE AND SUBTITLE FPGA Implementation of Burst-Mode Synchronization for SOQSPK-TG 5a. CONTRACT NUMBER: W900KK-11-C-0032 5b

  16. Análises de protocolos de braquiterapia, por alta taxa de dose, do controle de qualidade de alguns serviços locais, baseados no TG40, TG56 e ARCAL XXX Analysis of the high dose rate brachytherapy protocols of quality assurance programs of some local services, based on TG40, TG56 and ARCAL XXX.

    Directory of Open Access Journals (Sweden)

    Carmen S. Guzmán Calcina

    2001-08-01

    Full Text Available A braquiterapia por alta taxa de dose está recebendo atenção considerável na maioria dos países. Por isso, nos serviços que utilizam este equipamento exige-se que o desenvolvimento de um programa de controle de qualidade seja cada vez mais rigoroso, para garantir não apenas a segurança aos pacientes, mas também aos operadores e demais envolvidos. Este trabalho tem por objetivos fazer um levantamento dos tipos de testes para um equipamento de braquiterapia por alta taxa de dose, propostos pelos protocolos oficiais publicados (TG40, TG56 e ARCAL XXX e avaliar os tipos de testes que atualmente são realizados por alguns serviços de radioterapia, comparando-os com aqueles apresentados nos protocolos citados. Das análises feitas, observou-se que: a quanto aos protocolos oficiais, o TG56 é mais completo que o TG40 e o ARCAL XXX; b quanto às instituições analisadas, estas em geral se basearam no TG56 para elaborar seus próprios protocolos, os quais demonstraram ter também concordância com os outros já citados. Nestes protocolos, a inexistência dos testes anuais foi notada, o que pode ser explicado por sua aparição nas freqüências trimestral e semestral. Do produto deste estudo são apresentadas tabelas dos tipos de testes com suas respectivas freqüências de utilização, das quais um protocolo pode ser inferido para auxiliar na implementação, pelo menos, dos tipos de testes de controle de qualidade básicos e indispensáveis para o equipamento, garantindo, assim, um tratamento adequado aos pacientes e uma melhor segurança ao pessoal envolvido e, conseqüentemente, assegurando a garantia de qualidade na braquiterapia por alta taxa de dose.High dose rate brachytherapy has been increasingly recognized in most countries, and radiotherapy services using this equipment are encouraged to have a very efficient quality assurance program to ensure protection for patients, workers and other personnel involved. The objective of this

  17. Thermal analysis studies of ammonium uranyl carbonate

    International Nuclear Information System (INIS)

    Cao Xinsheng; Ma Xuezhong; Wang Fapin; Liu Naixin; Ji Changhong

    1988-01-01

    The simultaneous thermogravimetry and differential thermal analysis of the ammonium uranyl carbonate powder were performed with heat balance in the following atmosphers: Air, Ar and Ar-8%H 2 . The thermogravimetry and differential thermal analysis curves of the ammonium uranyl carbonate powder obtained from different source were reported and discussed

  18. The synthesis conditions, characterizations and thermal degradation studies of an etherified starch from an unconventional source

    International Nuclear Information System (INIS)

    Lawal, O.S.; Lechner, M.D.; Kulicke, W.M.

    2008-05-01

    Starch isolated from an under-utilized legume plant (pigeon pea) was carboxymethylated. Influences of reaction parameters were investigated on the degree of substitution (DS) and the reaction efficiency (RE). Studies showed that optimal DS of 1.12 could be reached at reaction efficiency of 80.6 % in isopropanol-water reaction medium (40 deg. C, 3h). The scanning electron microscopy showed that after carboxymethylation, the granular appearance of the native starch was distorted. Wide-angle X-ray diffractometry revealed that crystallinity was reduced significantly after carboxymethylation. The infrared spectra revealed new bands in the carboxymethyl starch at ν =1600, 1426 and 1324 cm -1 and they were attributed to carbonyl functional groups vibration, -CH2 scissoring and OH bending vibration respectively. Broad band 13 C NMR of carboxymethyl starch showed intense peak at δ 180.3 ppm and it was assigned for carbonyl carbon on the carboxymethyl substituent on the AGU (Anhydroglucose Unit). DEPT (Distortionless Enhancement by Polarization Transfer) 135 NMR showed negative signals which correspond to methylene carbons on the AGU. The differential scanning calorimetry (DSC) suggests loss of crystallinity after carboxymethylation. Thermogravimetry (TG), Derivative Thermogravimetry (DTG) and Differential Thermal Analysis (DTA) show that thermal stability improved after carboxymethylation. The study provides information on the preparation and characterization of a biomaterial from a new source which could be used alone or in the preparation of other functional polymers for diverse polymer applications. (author)

  19. Making the Tg-Confinement Effect Disappear in Thin Polystyrene Films: Good Physics vs. Inappropriate Analysis

    Science.gov (United States)

    Torkelson, John; Chen, Lawrence

    2013-03-01

    The Tg-confinement effect in polymers was first characterized in supported polystyrene (PS) films by Keddie et al. in 1994. Since then, many researchers have shown that (pseudo-)thermodynamic Tg measurements of supported PS films taken on cooling consistently yield the same qualitative results, with a decrease from bulk Tg beginning at 40-60 nm thickness and becoming very strong below 20 nm thickness. Some quantitative differences have been noted between studies, which may be ascribed to measurement method or the analysis employed. In 2004, we showed that the Tg-confinement effect in PS may be suppressed by adding several wt% of small-molecule diluents such as dioctyl phthalate. Recently, Kremer and co-workers (Macromolecules 2010, 43, 9937) reported that there was no Tg-confinement in supported PS films based on an analysis of the second derivative of ellipsometry data and use of a ninth order polynomial fit. Here, we demonstrate a new method for suppressing the Tg-confinement effect. In particular, PS made by emulsion polymerization yields no Tg-confinement effect as measured by ellipsometry or fluorescence, while PS made by anionic or conventional free radical polymerization yield strong Tg-confinement effects. The difference is hypothesized to result from surfactant in the emulsion polymerized PS. We also show that the absence of the Tg-confinement effect reported by Kremer is due to inappropriate analysis of ellipsometry data and that correct analysis yields Tg-confinement effects.

  20. Critical Assessment of Analytical Techniques in the Search for Biomarkers on Mars: A Mummified Microbial Mat from Antarctica as a Best-Case Scenario.

    Science.gov (United States)

    Blanco, Yolanda; Gallardo-Carreño, Ignacio; Ruiz-Bermejo, Marta; Puente-Sánchez, Fernando; Cavalcante-Silva, Erika; Quesada, Antonio; Prieto-Ballesteros, Olga; Parro, Víctor

    2017-10-01

    The search for biomarkers of present or past life is one of the major challenges for in situ planetary exploration. Multiple constraints limit the performance and sensitivity of remote in situ instrumentation. In addition, the structure, chemical, and mineralogical composition of the sample may complicate the analysis and interpretation of the results. The aim of this work is to highlight the main constraints, performance, and complementarity of several techniques that have already been implemented or are planned to be implemented on Mars for detection of organic and molecular biomarkers on a best-case sample scenario. We analyzed a 1000-year-old desiccated and mummified microbial mat from Antarctica by Raman and IR (infrared) spectroscopies (near- and mid-IR), thermogravimetry (TG), differential thermal analysis, mass spectrometry (MS), and immunological detection with a life detector chip. In spite of the high organic content (ca. 20% wt/wt) of the sample, the Raman spectra only showed the characteristic spectral peaks of the remaining beta-carotene biomarker and faint peaks of phyllosilicates over a strong fluorescence background. IR spectra complemented the mineralogical information from Raman spectra and showed the main molecular vibrations of the humic acid functional groups. The TG-MS system showed the release of several volatile compounds attributed to biopolymers. An antibody microarray for detecting cyanobacteria (CYANOCHIP) detected biomarkers from Chroococcales, Nostocales, and Oscillatoriales orders. The results highlight limitations of each technique and suggest the necessity of complementary approaches in the search for biomarkers because some analytical techniques might be impaired by sample composition, presentation, or processing. Key Words: Planetary exploration-Life detection-Microbial mat-Life detector chip-Thermogravimetry-Raman spectroscopy-NIR-DRIFTS. Astrobiology 17, 984-996.

  1. Synthesis, thermogravimetric study and crystal structure of an N-rich copper(II) compound with tren ligands and nitrate counter-anions

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-Toro, Inmaculada; Domínguez-Martín, Alicia [Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada (Spain); Choquesillo-Lazarte, Duane [Laboratorio de Estudios Cristalográficos, IACT, CSIC-Universidad de Granada, Av. de las Palmeras 4, E-18100 Armilla, Granada (Spain); Vílchez-Rodríguez, Esther [Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada (Spain); Department of Inorganic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain); Castiñeiras, Alfonso [Department of Inorganic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain); Niclós-Gutiérrez, Juan, E-mail: jniclos@ugr.es [Department of Inorganic Chemistry, Faculty of Pharmacy, University of Granada, 18071 Granada (Spain)

    2014-10-10

    The N-rich salt [{Cu(tren)}{sub 3}(μ{sub 3}-tren)]{sub 2}(NO{sub 3}){sub 12}·3H{sub 2}O has been studied by XRD and by coupled TG and FT-IR spectroscopy of the evolved gases. After water loss, thermal decomposition of the nitrate ions and some tren ligands in the salt are overlapped. - Highlights: • A novel N-rich copper(II)-tren complex has been crystallized as a 3-hydrated nitrate salt. • Tren acts both as tripodal tetradentate and as μ{sub 3}-tren bridging ligand. • Copper(II) centers exhibit distorted trigonal bipyramidal coordination. • Coupled thermogravimetry and FT-IR spectra of evolved gases have been used. • Decomposition of nitrate anions and tren ligands occurs in an overlapped step. - Abstract: The compound [{Cu(tren)}{sub 3}(μ3-tren)]{sub 2}(NO{sub 3}){sub 12}·3H{sub 2}O has been synthesized, crystallized and characterized by single crystal X-ray diffraction, thermogravimetry (TG) coupled to FT-IR spectroscopy of the evolved gases, TG–differential scanning calorimetry (DSC) and electronic (diffuse reflectance) and FT-IR spectroscopies. The sample loses the crystallization water between room temperature and 200 °C. The decomposition of the salt begins with an overlapped decomposition of nitrate anions and some tren ligands where CO{sub 2}, H{sub 2}O, CO, NH{sub 3}, N{sub 2}O, NO and NO{sub 2} are evolved (205–235 °C). Then decomposition of additional tren ligands takes place (235–725 °C). Finally a non-pure CuO residue is obtained at 725 °C.

  2. Compatibilidad química por calorimetría diferencial de barrido y termogravimetría del auranofin tabletas 3 mg Chemical compatibility of 3 mg Auranofin tablets demonstrated by differential scanning calorimetry and thermogravimetry

    Directory of Open Access Journals (Sweden)

    Luis Octavio Martínez Álvarez

    2011-03-01

    Full Text Available Como parte de la pre-estabilidad de la preformulación de auranofin tabletas, se realizó un estudio de compatibilidad química, para lo cual se emplearon técnicas de análisis térmico como la calorimetría diferencial de barrido y la termogravimetría. Previo a dichos estudios se caracterizó térmicamente por calorimetría diferencial de barrido el principio activo y cada uno de los excipientes. Posteriormente se procedió a la realización del estudio de compatibilidad química, mediante la preparación de mezclas físicas binarias entre el principio activo y cada uno de los excipientes. Se detectó por ambos métodos que el principio activo tuvo una transición física de fusión, no reportada en la literatura, lo que permitió poder calcular su pureza por calorimetría diferencial de barrido. Mediante la técnica calorimétrica fue posible inferir la ausencia de incompatibilidad química entre el principio activo y los excipientes estudiados. Además, mediante el cálculo de la energía de activación se estableció el siguiente orden de estabilidad térmica: auranofin:PVP> auranofin:lactosa> auranofin:explotab> auranofin:estearato> auranofin:aerosil> auranofin:celulosa, por lo que se recomienda el uso de estos excipientes en la elaboración de la formulación farmacéutica.As part of the pre-stability study of the Auranofin tablet pre-formulation, a chemical compatibility study was conducted using thermal analysis techniques such as the differential scanning calorimetry and the thermogravimetry. Prior to these studies, the active principle and each of the excipients were thermally characterized with the aid of the differential scanning calorimetry. Then, there proceeded to carry out the chemical compatibility study by preparing binary physical mixtures between the active principle and each of the excipients. Both methods showed that the active principle had a melting physical transition, not reported in the literature, which allowed

  3. Bulk synthesis of nanocrystalline urania powders by citrate gel-combustion method

    Science.gov (United States)

    Sanjay Kumar, D.; Ananthasivan, K.; Venkata Krishnan, R.; Amirthapandian, S.; Dasgupta, Arup

    2016-01-01

    Bulk quantities (60 g) of nanocrystalline (nc) free flowing urania powders with crystallite size ranging from 38 to 252 nm have been synthesized for the first time by the citrate gel combustion method. A systematic study of the influence of the fuel (citric acid) to oxidant (nitrate) ratio (R) on the characteristics of the urania powders has been carried out for the first time. Mixture with an "R" value of 0.25 exhibited a vigorous auto-ignition reaction. This reaction was investigated with Differential Scanning Calorimetry (DSC) and in-situ thermogravimetry coupled with differential thermal analysis and mass spectrometry (TG-DTA-MS). The bulk density, specific surface area, X-ray crystallite size, residual carbon and size distribution of particles of this powder were unique. Microscopic and microstructural investigation of selected samples revealed the presence of nanocrystals with irregular exfoliated morphology; their Electron Energy Loss Spectra testified the covalency of the U-O bond.

  4. Thermophysical and heat transfer properties of phase change material candidate for waste heat transportation system

    Science.gov (United States)

    Kaizawa, Akihide; Maruoka, Nobuhiro; Kawai, Atsushi; Kamano, Hiroomi; Jozuka, Tetsuji; Senda, Takeshi; Akiyama, Tomohiro

    2008-05-01

    A waste heat transportation system trans-heat (TH) system is quite attractive that uses the latent heat of a phase change material (PCM). The purpose of this paper is to study the thermophysical properties of various sugars and sodium acetate trihydrate (SAT) as PCMs for a practical TH system and the heat transfer property between PCM selected and heat transfer oil, by using differential scanning calorimetry (DSC), thermogravimetry-differential thermal analysis (TG-DTA) and a heat storage tube. As a result, erythritol, with a large latent heat of 344 kJ/kg at melting point of 117°C, high decomposition point of 160°C and excellent chemical stability under repeated phase change cycles was found to be the best PCM among them for the practical TH system. In the heat release experiments between liquid erythritol and flowing cold oil, we observed foaming phenomena of encapsulated oil, in which oil droplet was coated by solidification of PCM.

  5. Aging of Dielectric Properties below Tg

    DEFF Research Database (Denmark)

    Olsen, Niels Boye; Dyre, Jeppe; Christensen, Tage Emil

    The dielectric loss at 1Hz in TPP is studied during a temperature step from one equilibrium state to another. In the applied cryostate the temperature can be equilibrated on a timescale of 1 second. The aging time dependence of the dielectric loss is studied below Tg applying temperature steps...

  6. Ocular changes in TgF344-AD rat model of Alzheimer's disease.

    Science.gov (United States)

    Tsai, Yuchun; Lu, Bin; Ljubimov, Alexander V; Girman, Sergey; Ross-Cisneros, Fred N; Sadun, Alfredo A; Svendsen, Clive N; Cohen, Robert M; Wang, Shaomei

    2014-01-29

    Alzheimer's disease (AD) is the most common neurodegenerative disorder characterized by progressive decline in learning, memory, and executive functions. In addition to cognitive and behavioral deficits, vision disturbances have been reported in early stage of AD, well before the diagnosis is clearly established. To further investigate ocular abnormalities, a novel AD transgenic rat model was analyzed. Transgenic (Tg) rats (TgF344-AD) heterozygous for human mutant APPswe/PS1ΔE9 and age-matched wild type (WT) rats, as well as 20 human postmortem retinal samples from both AD and healthy donors were used. Visual function in the rodent was analyzed using the optokinetic response and luminance threshold recording from the superior colliculus. Immunohistochemistry on retinal and brain sections was used to detect various markers including amyloid-β (Aβ) plaques. As expected, Aβ plaques were detected in the hippocampus, cortex, and retina of Tg rats. Plaque-like structures were also found in two AD human whole-mount retinas. The choroidal thickness was significantly reduced in both Tg rat and in AD human eyes when compared with age-matched controls. Tg rat eyes also showed hypertrophic retinal pigment epithelial cells, inflammatory cells, and upregulation of complement factor C3. Although visual acuity was lower in Tg than in WT rats, there was no significant difference in the retinal ganglion cell number and retinal vasculature. In this study, we observed pathological changes in the choroid and in RPE cells in the TgF344-AD rat model; choroidal thinning was observed further in human AD retina. Along with Ab deposition, the inflammatory response was manifested by microglial recruitment and complement activation. Further studies are needed to elucidate the significance and mechanisms of these pathological changes [corrected].

  7. Specific expression of the vacuolar iron transporter, TgVit, causes iron accumulation in blue-colored inner bottom segments of various tulip petals.

    Science.gov (United States)

    Momonoi, Kazumi; Tsuji, Toshiaki; Kazuma, Kohei; Yoshida, Kumi

    2012-01-01

    Several flowers of Tulipa gesneriana exhibit a blue color in the bottom segments of the inner perianth. We have previously reported the inner-bottom tissue-specific iron accumulation and expression of the vacuolar iron transporter, TgVit1, in tulip cv. Murasakizuisho. To clarify whether the TgVit1-dependent iron accumulation and blue-color development in tulip petals are universal, we analyzed anthocyanin, its co-pigment components, iron contents and the expression of TgVit1 mRNA in 13 cultivars which show a blue color in the bottom segments of the inner perianth accompanying yellow- and white-colored inner-bottom petals. All of the blue bottom segments contained the same anthocyanin component, delphinidin 3-rutinoside. The flavonol composition varied with cultivar and tissue part. The major flavonol in the bottom segments of the inner perianth was rutin. The iron content in the upper part was less than that in the bottom segments of the inner perianth. The iron content in the yellow and white petals was higher in the bottom segment of the inner perianth than in the upper tissues. TgVit1 mRNA expression was apparent in all of the bottom tissues of the inner perianth. The result of a reproduction experiment by mixing the constituents suggests that the blue coloration in tulip petals is generally caused by iron complexation to delphinidin 3-rutinoside and that the iron complex is solubilized and stabilized by flavonol glycosides. TgVit1-dependent iron accumulation in the bottom segments of the inner perianth might be controlled by an unknown system that differentiated the upper parts and bottom segments of the inner perianth.

  8. Implications of Thyroglobulin Antibody Positivity in Patients with Differentiated Thyroid Cancer

    DEFF Research Database (Denmark)

    Verburg, Frederik A; Luster, Markus; Cupini, Cristina

    2013-01-01

    Background: Even though the presence of antithyroglobulin antibodies (TgAbs) represents a significant problem in the follow-up of patients with differentiated thyroid cancer (DTC), the current guidelines on the management of DTC that have been published in recent years contain no text concerning...... the methods to be used for detecting such antibody-related interference in thyroglobulin (Tg) measurement or how to manage TgAb-positive patients in whom Tg cannot be used reliably as a tumor marker. Aim: An international group of experts from the European Thyroid Association Cancer Research Network who...... insufficient evidence was available, a thorough discussion by a group of physician-scientists, all of whom have a distinguished track record in thyroid cancer care, was held to arrive at a consensus expert opinion. The questions and answers discussed were then summarized into an algorithm for the management...

  9. Relationship TG/HDL-C and insulin resistance in adult women by nutritional status

    Directory of Open Access Journals (Sweden)

    Lorena Belén

    2014-04-01

    Full Text Available Introduction: The ratio assessment TG/HDL-C is an indicator of LDL size, facilitating the detection of individuals with increased atherogenic risk. Estimating the size of the LDL becomes important, especially in patients with TG values near the upper limit of normal values of reference and HDL-C. The objective of the study is to estimate the association between TG/HDL-C and insulin resistance (IR by nutritional status in adult women attending the Foundation for Endocrine Metabolic Diseases Research and Applied Clinical Research (FIEEM.Material and methods: Design Cross-sectional, non-pregnant adult women, apparently healthy, older than 30 years old, attending FIEEM in the Autonomous City of Buenos Aires. Dependent variable: TG/HDL-C ≥ 3.0 considered high value. Independent variables: IR by homeostatic model index HOMA-IR ≥ 2.5 categorizing the sample into two groups: with and without IR, and controlled by nutritional status using body mass index (BMI and waist circumference (CC. SPSS Statistics 15.0, calculating X2 or Fisher exact test, OR with confidence intervals of 95% and establishing logistic regression p value < 0.05.Results: We evaluated a purposive sample of 104 women (31.4% and 26% IR with TG/HDL-C high. 84.6% were overweight or obese and 88.5% increased CC. Women with BMI had significantly increased 0.15-fold increased risk (95% CI = 0.01 to 1.26 for TG/HDL-C high (p = 0.04 than the control women. There was no significance with increased CC. The ratio TG/HDL-C high IR was significantly correlated (r = 0.30 p = 0.002.Conclusions: Body weight was significantly associated with IR and the ratio TG/HDL-C increased. This ratio correlated significantly with IR in apparently healthy women.

  10. Synthesis, Characterization and Biological Studies of New Linear Thermally Stable Schiff Base Polymers with Flexible Spacers.

    Science.gov (United States)

    Qureshi, Farah; Khuhawar, Muhammad Yar; Jahangir, Taj Muhammad; Channar, Abdul Hamid

    2016-01-01

    Five new linear Schiff base polymers having azomethine structures, ether linkages and extended aliphatic chain lengths with flexible spacers were synthesized by polycondensation of dialdehyde (monomer) with aliphatic and aromatic diamines. The formation yields of monomer and polymers were obtained within 75-92%. The polymers with flexible spacers of n-hexane were somewhat soluble in acetone, chloroform, THF, DMF and DMSO on heating. The monomer and polymers were characterized by melting point, elemental microanalysis, FT-IR, (1)HNMR, UV-Vis spectroscopy, thermogravimetry (TG), differential thermal analysis (DTA), fluorescence emission, scanning electron microscopy (SEM) and viscosities and thermodynamic parameters measurements of their dilute solutions. The studies supported formation of the monomer and polymers and on the basis of these studies their structures have been assigned. The synthesized polymers were tested for their antibacterial and antifungal activities.

  11. GLUT4 expression in human muscle fibres is not correlated with intracellular triglyceride (TG) content. Is TG a maker or a marker of insulin resistance?

    DEFF Research Database (Denmark)

    Gaster, M; Ottosen, P D; Vach, W

    2003-01-01

    diabetic subjects, and young lean controls. TG density was significantly higher in slow compared to fast fibres in all studied subjects (pslow twitch fibres of obese diabetic subjects compared to obese (p...We have recently reported a progressive decline in the expression of glucose transporter isoform 4 (GLUT4) from control subjects through obese non-diabetics to obese type 2 diabetic subjects, indicating that the reduced GLUT4 in slow twitch fibres could be secondary to obesity. In this study we...... densities in slow and fast fibres did not correlate with the corresponding GLUT4 density in the same fibres in our study groups (p>0.05). Plasma TG and FFA did not correlate with GLUT4 expression in slow or fast fibres (p>0.05). In conclusion, TG content was increased in diabetic slow fibres with a reduced...

  12. Facile solvothermal synthesis of a graphene nanosheet-bismuth oxide composite and its electrochemical characteristics

    International Nuclear Information System (INIS)

    Wang Huanwen; Hu Zhongai; Chang Yanqin; Chen Yanli; Lei Ziqiang; Zhang Ziyu; Yang Yuying

    2010-01-01

    This work demonstrates a novel and facile route for preparing graphene-based composites comprising of metal oxide nanoparticles and graphene. A graphene nanosheet-bismuth oxide composite as electrode materials of supercapacitors was firstly synthesized by thermally treating the graphene-bismuth composite, which was obtained through simultaneous solvothermal reduction of the colloidal dispersions of negatively charged graphene oxide sheets in N,N-dimethyl formamide (DMF) solution of bismuth cations at 180 o C. The morphology, composition, and microstructure of the composites together with pure graphite oxide, and graphene were characterized using powder X-ray diffraction (XRD), FT-IR, field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), thermogravimetry and differential thermogravimetry (TG-DTG). The electrochemical behaviors were measured by cyclic voltammogram (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS). The specific capacitance of 255 F g -1 (based on composite) is obtained at a specific current of 1 A g -1 as compared with 71 F g -1 for pure graphene. The loaded-bismuth oxide achieves a specific capacitance as high as 757 F g -1 even at 10 A g -1 . In addition, the graphene nanosheet-bismuth oxide composite electrode exhibits the excellent rate capability and well reversibility.

  13. Facile solvothermal synthesis of a graphene nanosheet-bismuth oxide composite and its electrochemical characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Wang Huanwen [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Hu Zhongai, E-mail: zhongai@nwnu.edu.c [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Chang Yanqin; Chen Yanli; Lei Ziqiang; Zhang Ziyu; Yang Yuying [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China)

    2010-12-01

    This work demonstrates a novel and facile route for preparing graphene-based composites comprising of metal oxide nanoparticles and graphene. A graphene nanosheet-bismuth oxide composite as electrode materials of supercapacitors was firstly synthesized by thermally treating the graphene-bismuth composite, which was obtained through simultaneous solvothermal reduction of the colloidal dispersions of negatively charged graphene oxide sheets in N,N-dimethyl formamide (DMF) solution of bismuth cations at 180 {sup o}C. The morphology, composition, and microstructure of the composites together with pure graphite oxide, and graphene were characterized using powder X-ray diffraction (XRD), FT-IR, field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), thermogravimetry and differential thermogravimetry (TG-DTG). The electrochemical behaviors were measured by cyclic voltammogram (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS). The specific capacitance of 255 F g{sup -1} (based on composite) is obtained at a specific current of 1 A g{sup -1} as compared with 71 F g{sup -1} for pure graphene. The loaded-bismuth oxide achieves a specific capacitance as high as 757 F g{sup -1} even at 10 A g{sup -1}. In addition, the graphene nanosheet-bismuth oxide composite electrode exhibits the excellent rate capability and well reversibility.

  14. Lamin A/C Is Required for ChAT-Dependent Neuroblastoma Differentiation.

    Science.gov (United States)

    Guglielmi, Loredana; Nardella, Marta; Musa, Carla; Iannetti, Ilaria; Arisi, Ivan; D'Onofrio, Mara; Storti, Andrea; Valentini, Alessandra; Cacci, Emanuele; Biagioni, Stefano; Augusti-Tocco, Gabriella; D'Agnano, Igea; Felsani, Armando

    2017-07-01

    The mouse neuroblastoma N18TG2 clone is unable to differentiate and is defective for the enzymes of the biosynthesis of neurotransmitters. The forced expression of choline acetyltransferase (ChAT) in these cells results in the synthesis and release of acetylcholine (Ach) and hence in the expression of neurospecific features and markers. To understand how the expression of ChAT triggered neuronal differentiation, we studied the differences in genome-wide transcription profiles between the N18TG2 parental cells and its ChAT-expressing 2/4 derived clone. The engagement of the 2/4 cells in the neuronal developmental program was confirmed by the increase of the expression level of several differentiation-related genes and by the reduction of the amount of transcripts of cell cycle genes. At the same time, we observed a massive reorganization of cytoskeletal proteins in terms of gene expression, with the accumulation of the nucleoskeletal lamina component Lamin A/C in differentiating cells. The increase of the Lmna transcripts induced by ChAT expression in 2/4 cells was mimicked treating the parental N18TG2 cells with the acetylcholine receptor agonist carbachol, thus demonstrating the direct role played by this receptor in neuron nuclei maturation. Conversely, a treatment of 2/4 cells with the muscarinic receptor antagonist atropine resulted in the reduction of the amount of Lmna RNA. Finally, the hypothesis that Lmna gene product might play a crucial role in the ChAT-dependent molecular differentiation cascade was strongly supported by Lmna knockdown in 2/4 cells leading to the downregulation of genes involved in differentiation and cytoskeleton formation and to the upregulation of genes known to regulate self-renewal and stemness.

  15. Biomechanical assays amniotic membrane preserved in glycerol correlating with optical coherence tomography (OCT) and thermal gravimetric analysis (TG)

    International Nuclear Information System (INIS)

    Soares, Fernando Augusto N.; Santin, Stefany P.; Martino Junior, Antonio C.; Machado, Luci Diva B.; Freitas, Anderson Z.; Mathor, Monica B.

    2013-01-01

    Young's modulus, the OCT technique, to generate high-resolution images in real time being a non-destructive technique, thermogravimetry (TG) assessing the amount of water and rate of water output membranes after treatment with ionizing radiation, relating the possible changes with non-irradiated tissue. However the results of the tensile test had the same behavior compared to the values of total attenuation coefficient by OCT, in addition the dehydration rate analyzed by TG had no statistically significant variation to some radiation doses. (author)

  16. Biomechanical assays amniotic membrane preserved in glycerol correlating with optical coherence tomography (OCT) and thermal gravimetric analysis (TG)

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Fernando Augusto N.; Santin, Stefany P.; Martino Junior, Antonio C.; Machado, Luci Diva B.; Freitas, Anderson Z.; Mathor, Monica B., E-mail: fernandonevessoares@yahoo.com.br [Instituto de Pesquisas Energetias Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Young's modulus, the OCT technique, to generate high-resolution images in real time being a non-destructive technique, thermogravimetry (TG) assessing the amount of water and rate of water output membranes after treatment with ionizing radiation, relating the possible changes with non-irradiated tissue. However the results of the tensile test had the same behavior compared to the values of total attenuation coefficient by OCT, in addition the dehydration rate analyzed by TG had no statistically significant variation to some radiation doses. (author)

  17. Thermogravimetric study and kinetic analysis of fungal pretreated corn stover using the distributed activation energy model.

    Science.gov (United States)

    Ma, Fuying; Zeng, Yelin; Wang, Jinjin; Yang, Yang; Yang, Xuewei; Zhang, Xiaoyu

    2013-01-01

    Non-isothermal thermogravimetry/derivative thermogravimetry (TG/DTG) measurements are used to determine pyrolytic characteristics and kinetics of lignocellulose. TG/DTG experiments at different heating rates with corn stover pretreated with monocultures of Irpex lacteus CD2 and Auricularia polytricha AP and their cocultures were conducted. Heating rates had little effect on the pyrolysis process, but the peak of weight loss rate in the DTG curves shifted towards higher temperature with heating rate. The maximum weight loss of biopretreated samples was 1.25-fold higher than that of the control at the three heating rates, and the maximum weight loss rate of the co-culture pretreated samples was intermediate between that of the two mono-cultures. The activation energies of the co-culture pretreated samples were 16-72 kJ mol(-1) lower than that of the mono-culture at the conversion rate range from 10% to 60%. This suggests that co-culture pretreatment can decrease activation energy and accelerate pyrolysis reaction thus reducing energy consumption. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Direct encapsulation of water-soluble drug into silica microcapsules for sustained release applications

    International Nuclear Information System (INIS)

    Wang Jiexin; Wang Zhihui; Chen Jianfeng; Yun, Jimmy

    2008-01-01

    Direct encapsulation of water-soluble drug into silica microcapsules was facilely achieved by a sol-gel process of tetraethoxysilane (TEOS) in W/O emulsion with hydrochloric acid (HCl) aqueous solution containing Tween 80 and drug as well as cyclohexane solution containing Span 80. Two water-soluble drugs of gentamicin sulphate (GS) and salbutamol sulphate (SS) were chosen as model drugs. The characterization of drug encapsulated silica microcapsules by scanning electronic microscopy (SEM), FTIR, thermogravimetry (TG) and N 2 adsorption-desorption analyses indicated that drug was successfully entrapped into silica microcapsules. The as-prepared silica microcapsules were uniform spherical particles with hollow structure, good dispersion and a size of 5-10 μm, and had a specific surface area of about 306 m 2 /g. UV-vis and thermogravimetry (TG) analyses were performed to determine the amount of drug encapsulated in the microcapsules. The BJH pore size distribution (PSD) of silica microcapsules before and after removing drug was examined. In vitro release behavior of drug in simulated body fluid (SBF) revealed that such system exhibited excellent sustained release properties

  19. Endogenous murine tau promotes neurofibrillary tangles in 3xTg-AD mice without affecting cognition.

    Science.gov (United States)

    Baglietto-Vargas, David; Kitazawa, Masashi; Le, Elaine J; Estrada-Hernandez, Tatiana; Rodriguez-Ortiz, Carlos J; Medeiros, Rodrigo; Green, Kim N; LaFerla, Frank M

    2014-02-01

    Recent studies on tauopathy animal models suggest that the concomitant expression of the endogenous murine tau delays the pathological accumulation of human tau, and interferes with the disease progression. To elucidate the role of endogenous murine tau in a model with both plaques and tangles, we developed a novel transgenic mouse model by crossing 3xTg-AD with mtauKO mice (referred to as 3xTg-AD/mtauKO mice). Therefore, this new model allows us to determine the pathological consequences of the murine tau. Here, we show that 3xTg-AD/mtauKO mice have lower tau loads in both soluble and insoluble fractions, and lower tau hyperphosphorylation level in the soluble fraction relative to 3xTg-AD mice. In the 3xTg-AD model endogenous mouse tau is hyperphosphorylated and significantly co-aggregates with human tau. Despite the deletion of the endogenous tau gene in 3xTg-AD/mtauKO mice, cognitive dysfunction was equivalent to 3xTg-AD mice, as there was no additional impairment on a spatial memory task, and thus despite increased tau phosphorylation, accumulation and NFTs in 3xTg-AD mice no further effects on cognition are seen. These findings provide better understanding about the role of endogenous tau to Alzheimer's disease (AD) pathology and for developing new AD models. © 2013.

  20. Detecting spatial memory deficits beyond blindness in tg2576 Alzheimer mice.

    Science.gov (United States)

    Yassine, Nour; Lazaris, Anelise; Dorner-Ciossek, Cornelia; Després, Olivier; Meyer, Laurence; Maitre, Michel; Mensah-Nyagan, Ayikoe Guy; Cassel, Jean-Christophe; Mathis, Chantal

    2013-03-01

    The retinal degeneration Pde6b(rd1) (rd) mutation can be a major pitfall in behavioral studies using tg2576 mice bred on a B6:SJL genetic background, 1 of the most widely used models of Alzheimer's disease. After a pilot study in wild type mice, performance of 8- and 16-month-old tg2576 mice were assessed in several behavioral tasks with the challenge of selecting 1 or more task(s) showing robust memory deficits on this genetic background. Water maze acquisition was impossible in rd homozygotes, whereas Y-maze alternation, object recognition, and olfactory discrimination were unaffected by both the transgene and the rd mutation. Spatial memory retention of 8- and 16-month-old tg2576 mice, however, was dramatically affected independently of the rd mutation when mice had to recognize a spatial configuration of objects or to perform the Barnes maze. Thus, the latter tasks appear extremely useful to evaluate spatial memory deficits and to test cognitive therapies in tg2576 mice and other mouse models bred on a background susceptible to visual impairment. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Activation of transglutaminase 2 by nerve growth factor in differentiating neuroblastoma cells: A role in cell survival and neurite outgrowth.

    Science.gov (United States)

    Algarni, Alanood S; Hargreaves, Alan J; Dickenson, John M

    2018-02-05

    NGF (nerve growth factor) and tissue transglutaminase (TG2) play important roles in neurite outgrowth and modulation of neuronal cell survival. In this study, we investigated the regulation of TG2 transamidase activity by NGF in retinoic acid-induced differentiating mouse N2a and human SH-SY5Y neuroblastoma cells. TG2 transamidase activity was determined using an amine incorporation and a peptide cross linking assay. In situ TG2 activity was assessed by visualising the incorporation of biotin-X-cadaverine using confocal microscopy. The role of TG2 in NGF-induced cytoprotection and neurite outgrowth was investigated by monitoring hypoxia-induced cell death and appearance of axonal-like processes, respectively. The amine incorporation and protein crosslinking activity of TG2 increased in a time and concentration-dependent manner following stimulation with NGF in N2a and SH-SY5Y cells. NGF mediated increases in TG2 activity were abolished by the TG2 inhibitors Z-DON (Z-ZON-Val-Pro-Leu-OMe; Benzyloxycarbonyl-(6-Diazo-5-oxonorleucinyl)-l-valinyl-l-prolinyl-l-leucinmethylester) and R283 (1,3,dimethyl-2[2-oxo-propyl]thio)imidazole chloride) and by pharmacological inhibition of extracellular signal-regulated kinases 1 and 2 (ERK1/2), protein kinase B (PKB) and protein kinase C (PKC), and removal of extracellular Ca 2+ . Fluorescence microscopy demonstrated NGF induced in situ TG2 activity. TG2 inhibition blocked NGF-induced attenuation of hypoxia-induced cell death and neurite outgrowth in both cell lines. Together, these results demonstrate that NGF stimulates TG2 transamidase activity via a ERK1/2, PKB and PKC-dependent pathway in differentiating mouse N2a and human SH-SY5Y neuroblastoma cells. Furthermore, NGF-induced cytoprotection and neurite outgrowth are dependent upon TG2. These results suggest a novel and important role of TG2 in the cellular functions of NGF. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. TG 220 MW hydraulic control system diagnostics

    International Nuclear Information System (INIS)

    Svabcik, A.

    1996-01-01

    The TG power output control system comprises a hydraulic and an electronic part. TG speed, power output or the main steam header pressure (HPK) depend on the steam flow at the turbine inlet. The steam admission into the turbine is controlled by four control valves and one by-pass valve in case of the HP part and by four capture flap valves in case of the LP part. The task of the SKODA K-220 MW turbine protection and control systems is to provide both the turbine speed and power output control to the setpoint value. Diagnostic measurements were aimed at getting an overview of both technical and functional states of all power output control elements. Principally, it can be stated that some deficiencies of a design nature originating from the manufacturer's factory were revealed and some other deficiencies related to hydraulic control elements functionality were identified more closely by the new method. 5 figs

  3. TG 220 MW hydraulic control system diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Svabcik, A [Atomova Elektraren Bohunice, Jaslovske Bohunice (Slovakia)

    1997-12-31

    The TG power output control system comprises a hydraulic and an electronic part. TG speed, power output or the main steam header pressure (HPK) depend on the steam flow at the turbine inlet. The steam admission into the turbine is controlled by four control valves and one by-pass valve in case of the HP part and by four capture flap valves in case of the LP part. The task of the SKODA K-220 MW turbine protection and control systems is to provide both the turbine speed and power output control to the setpoint value. Diagnostic measurements were aimed at getting an overview of both technical and functional states of all power output control elements. Principally, it can be stated that some deficiencies of a design nature originating from the manufacturer`s factory were revealed and some other deficiencies related to hydraulic control elements functionality were identified more closely by the new method. 5 figs.

  4. High-Tg TOPAS mPOF strain sensing at 110 degrees

    DEFF Research Database (Denmark)

    Nielsen, Kristian; Markos, Christos; Stefani, Alessio

    2013-01-01

    We demonstrate a mPOF made of high-Tg TOPAS grade 5013 with Tg = 135°C. We inscribe FBGs into the fiber and demonstrate strain sensing of 2.5% strain at 98°C, further we also demonstrate strain sensing at a record high temperature of 110°C. The Bragg wavelengths of the FBGs are around 860 nm, whe...... the propagation loss is 5.1dB/m, close to the fiber loss minimum of 3.67dB/m at 787nm....

  5. Tg.rasH2 Mice and not CByB6F1 Mice Should Be Used for 28-Day Dose Range Finding Studies Prior to 26-Week Tg.rasH2 Carcinogenicity Studies.

    Science.gov (United States)

    Paranjpe, Madhav G; Belich, Jessica; Vidmar, Tom J; Elbekai, Reem H; McKeon, Marie; Brown, Caren

    Our recent retrospective analysis of data, collected from 29 Tg.rasH2 mouse carcinogenicity studies, determined how successful the strategy of choosing the high dose for the 26-week studies was based on the estimated maximum tolerated dose (EMTD) derived from earlier 28-day dose range finding (DRF) studies conducted in CByB6F1 mice. Our analysis demonstrated that the high doses applied at EMTD in the 26-week Tg.rasH2 studies failed to detect carcinogenic effects. To investigate why the dose selection process failed in the 26-week carcinogenicity studies, the initial body weights, terminal body weights, body weight gains, food consumption, and mortality from the first 4 weeks of 26-week studies with Tg.rasH2 mice were compared with 28-day DRF studies conducted with CByB6F1 mice. Both the 26-week and the earlier respective 28-day studies were conducted with the exact same vehicle, test article, and similar dose levels. The analysis of our results further emphasizes that the EMTD and subsequent lower doses, determined on the basis of the 28-day studies in CByB6F1 mice, may not be an accurate strategy for selecting appropriate dose levels for the 26-week carcinogenicity studies in Tg.rasH2 mice. Based on the analysis presented in this article, we propose that the Tg.rasH2 mice and not the CByB6F1 mice should be used in future DRF studies. The Tg.rasH2 mice demonstrate more toxicity than the CByB6F1 mice, possibly because of their smaller size compared to CByB6F1 mice. Also, the Tg.rasH2 males appear to be more sensitive than the female Tg.rasH2 mice.

  6. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite.

    Science.gov (United States)

    Sofronia, Ancuta M; Baies, Radu; Anghel, Elena M; Marinescu, Cornelia A; Tanasescu, Speranta

    2014-10-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400°C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis-TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800°C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Assessment of display performance for medical imaging systems: Executive summary of AAPM TG18 report

    International Nuclear Information System (INIS)

    Samei, Ehsan; Badano, Aldo; Chakraborty, Dev

    2005-01-01

    Digital imaging provides an effective means to electronically acquire, archive, distribute, and view medical images. Medical imaging display stations are an integral part of these operations. Therefore, it is vitally important to assure that electronic display devices do not compromise image quality and ultimately patient care. The AAPM Task Group 18 (TG18) recently published guidelines and acceptance criteria for acceptance testing and quality control of medical display devices. This paper is an executive summary of the TG18 report. TG18 guidelines include visual, quantitative, and advanced testing methodologies for primary and secondary class display devices. The characteristics, tested in conjunction with specially designed test patterns (i.e., TG18 patterns), include reflection, geometric distortion, luminance, the spatial and angular dependencies of luminance, resolution, noise, glare, chromaticity, and display artifacts. Geometric distortions are evaluated by linear measurements of the TG18-QC test pattern, which should render distortion coefficients less than 2%/5% for primary/secondary displays, respectively. Reflection measurements include specular and diffuse reflection coefficients from which the maximum allowable ambient lighting is determined such that contrast degradation due to display reflection remains below a 20% limit and the level of ambient luminance (L amb ) does not unduly compromise luminance ratio (LR) and contrast at low luminance levels. Luminance evaluation relies on visual assessment of low contrast features in the TG18-CT and TG18-MP test patterns, or quantitative measurements at 18 distinct luminance levels of the TG18-LN test patterns. The major acceptable criteria for primary/secondary displays are maximum luminance of greater than 170/100 cd/m 2 , LR of greater than 250/100, and contrast conformance to that of the grayscale standard display function (GSDF) of better than 10%/20%, respectively. The angular response is tested to

  8. Aged Tg2576 mice are impaired on social memory and open field habituation tests.

    Science.gov (United States)

    Deacon, R M J; Koros, E; Bornemann, K D; Rawlins, J N P

    2009-02-11

    In a previous publication [Deacon RMJ, Cholerton LL, Talbot K, Nair-Roberts RG, Sanderson DJ, Romberg C, et al. Age-dependent and -independent behavioral deficits in Tg2576 mice. Behav Brain Res 2008;189:126-38] we found that very few cognitive tests were suitable for demonstrating deficits in Tg2576 mice, an amyloid over-expression model of Alzheimer's disease, even at 23 months of age. However, in a retrospective analysis of a separate project on these mice, tests of social memory and open field habituation revealed large cognitive impairments. Controls showed good open field habituation, but Tg2576 mice were hyperactive and failed to habituate. In the test of social memory for a juvenile mouse, controls showed considerably less social investigation on the second meeting, indicating memory of the juvenile, whereas Tg2576 mice did not show this decrement.As a control for olfactory sensitivity, on which social memory relies, the ability to find a food pellet hidden under wood chip bedding was assessed. Tg2576 mice found the pellet as quickly as controls. As this test requires digging ability, this was independently assessed in tests of burrowing and directly observed digging. In line with previous results and the hippocampal dysfunction characteristic of aged Tg2576 mice, they both burrowed and dug less than controls.

  9. Thermogravimetry for optimization of chloride pyro hydrolytic separations in zirconia-magnesia matrix

    International Nuclear Information System (INIS)

    Pires, M.A.F.; Dantas, E.S.K.

    1992-08-01

    A fast and accurate method for chloride ion determination in zirconia-magnesia matrix was studied the method consists in the pyro hydrolysis of the oxides at 900 o C, using a quartz apparatus, during thirty minutes and further determination of the chloride ion collected by means of either ion-selective electrode or ion chromatography. The thermogravimetric curves (TG curves) of the metal oxides and oxychlorides provide all the information about the chloride ion evolution temperature and the influence of pyro hydrolytic accelerators (U 3 O 8 ) on ion evolution. (author)

  10. TG2 regulates the heat-shock response by the post-translational modification of HSF1.

    Science.gov (United States)

    Rossin, Federica; Villella, Valeria Rachela; D'Eletto, Manuela; Farrace, Maria Grazia; Esposito, Speranza; Ferrari, Eleonora; Monzani, Romina; Occhigrossi, Luca; Pagliarini, Vittoria; Sette, Claudio; Cozza, Giorgio; Barlev, Nikolai A; Falasca, Laura; Fimia, Gian Maria; Kroemer, Guido; Raia, Valeria; Maiuri, Luigi; Piacentini, Mauro

    2018-05-11

    Heat-shock factor 1 (HSF1) is the master transcription factor that regulates the response to proteotoxic stress by controlling the transcription of many stress-responsive genes including the heat-shock proteins. Here, we show a novel molecular mechanism controlling the activation of HSF1. We demonstrate that transglutaminase type 2 (TG2), dependent on its protein disulphide isomerase activity, triggers the trimerization and activation of HSF1 regulating adaptation to stress and proteostasis impairment. In particular, we find that TG2 loss of function correlates with a defect in the nuclear translocation of HSF1 and in its DNA-binding ability to the HSP70 promoter. We show that the inhibition of TG2 restores the unbalance in HSF1-HSP70 pathway in cystic fibrosis (CF), a human disorder characterized by deregulation of proteostasis. The absence of TG2 leads to an increase of about 40% in CFTR function in a new experimental CF mouse model lacking TG2. Altogether, these results indicate that TG2 plays a key role in the regulation of cellular proteostasis under stressful cellular conditions through the modulation of the heat-shock response. © 2018 The Authors.

  11. Characterization of polyurethane based on polyol synthesized from glycerol and hexamethylene diisocyanate

    International Nuclear Information System (INIS)

    Carvalho, Sabrina M.; Weber, Vanessa; Silva, Tailu N.; Barreto, Pedro L.M.

    2009-01-01

    A new polyol based on glycerol was synthesized and used in the production of polyurethane by reaction with hexamethylene diisocyanate. The polyol was characterized by nuclear magnetic resonance spectroscopy (NMR) and Fourier transform-infrared spectroscopy (FTIR). The polyurethane produced was characterized by FTIR, thermogravimetry (TG), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The polyol was shown to be reactive with hexamethylene diisocyanate, as the FTIR spectrum showed no free isocyanate groups and identified the presence of group -C=O of urethane groups. Analysis by DSC showed that the sample of polyurethane has a glass transition temperature around -8.53 deg C and SEM micrographs showed fracture and surface continuous and not broken. The thermogravimetric analysis showed that the polyurethane produced has a high thermal stability with a temperature of maximum degradation around 430 deg C. (author)

  12. Preparation of CoFeO Nanocrystallites by Solvothermal Process and Its Catalytic Activity on the Thermal Decomposition of Ammonium Perchlorate

    Directory of Open Access Journals (Sweden)

    Shusen Zhao

    2010-01-01

    Full Text Available Nanometer cobalt ferrite (CoFe2O4 was synthesized by polyol-medium solvothermal method and characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, and selected area electron diffraction (SAED. Further, the catalytic activity and kinetic parameters of CoFe2O4 nanocrystallites on the thermal decomposition behavior of ammonium perchlorate (AP have been investigated by thermogravimetry and differential scanning calorimetry analysis (TG-DSC. The results imply that the catalytic performance of CoFe2O4 nanocrystallites is significant and the decrease in the activation energy and the increase in the rate constant for AP further confirm the enhancement in catalytic activity of CoFe2O4 nanocrystallites. A mechanism based on an proton transfer process has also been proposed for AP in the presence of CoFe2O4 nanocrystallites.

  13. Preparation of 5-benzotriazolyl-4-hydroxy-3-sec-butylbenzenesulfonate anion-intercalated layered double hydroxide and its photostabilizing effect on polypropylene

    International Nuclear Information System (INIS)

    Li Dianqing; Tuo Zhenjun; Evans, David G.; Duan Xue

    2006-01-01

    An organic UV absorber has been intercalated into a layered double hydroxide (LDH) host by ion-exchange method using ZnAl-NO 3 -LDH as a precursor with an aqueous solution of the sodium salt of 5-benzotriazolyl-4-hydroxy-3-sec-butylbenzenesulfonic acid (BZO). After intercalation of the UV absorber, the interlayer distance in the LDHs increases from 0.89 to 2.32 nm. Infrared spectra and thermogravimetry and differential thermal analysis (TG-DTA) curves reveal the presence of a complex system of supramolecular host-guest interactions. The thermostability of BZO is markedly enhanced by intercalation in the LDH host. ZnAl-BZO-LDHs/polypropylene composite materials exhibit excellent UV photostability. - Graphical abstract: Intercalation of an organic UV absorber in a layered double hydroxide host leads to an enhancement of its photo- and thermal stability

  14. Effect of chitosan content on morphology and thermal properties of poly (vinyl alcohol) / chitosan blends; Eefeito do teor de quitosana na morfologia e propriedades termicas das blendas de poli (alcool vinilico) / quitosana

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Barbara Fernanda F. dos; Silva, Jessica Raquel M.B. da; Leite, Itamara Farias, E-mail: itamaraf@gmail.com [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Centro de Tecnologia. Departamento de Engenharia de Materiais

    2015-07-01

    The objective of this work consists in the preparation and characterization of blends consisting of biodegradable polymers, chitosan (CS) and poly (vinyl alcohol) (PVA), to evaluate the effect of different chitosan content in morphology and thermal properties of PVA blends/CS, prepared by the solution method. Therefore, the blends were characterized by Infrared Spectroscopy Fourier Transform (FTIR), X-Ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG). The results showed a good degree of interaction between the polymers of the blend constituents, suggesting certain degree of miscibility in the mixture. It was observed by XRD, that as the chitosan content in the mixture decreases PVA/CS, there is a slight increase in crystallinity. In comparative analysis, is observed that the composition PVA1/CS1 was the composition that showed improvement in thermal stability. (author)

  15. SU-F-T-22: Clinical Implications When Using TG-186 (ACE) Heterogeneity Software

    Energy Technology Data Exchange (ETDEWEB)

    Likhacheva, A; Grade, E; Sadeghi, A; Sokolowski, T [Arizona Cancer Specialists, Mesa, AZ (United States)

    2016-06-15

    Purpose: The purpose of this study is to compare dosimetric calculations using traditional TG-43 formalism and Oncentra Brachy Advanced Collapsed cone Engine (ACE) TG-186 calculation algorithm in clinical setting. Methods: We analyzed dosimetry of four patients treated with accelerated partial breast irradiation using a multi-channel intracavitary device (SAVI). All patients were treated to 34 Gy in 10 fractions using a high-dose-rate (192) Ir source. The plans were designed and treated using the TG-43 model. ACE was used to assess the effect heterogeneity correction on various dosimetric parameters. Mass density was estimated using Hounsfield units. Results: Compared to TG-43 formalism, ACE estimated lower doses to targets and organs at risk. The mean difference was 19.8% (range 15.3–24.1%) for PTV-eval V200, 12.0% (range 9.7–17.7%) for PTV-eval V150, 4.3% (range 3.3–6.5%) for PTV-eval D95, 3.3% (range 1.4–5.4%) for PTV-eval D90, 5.4% (range 2.9–9.9%) for maximum rib dose, and 5.7% (2.4–7.4%) for maximum skin dose. There was no correlation between the magnitude of the difference and the PTV-eval volume, air volume, or tissue-applicator conformance. Conclusion: Based on our preliminary study, the TG-43 algorithm appears to overestimate the dose to targets and organs at risk when compared to the ACE TG-186 software. We hypothesize that air adjacent to the SAVI struts contributes to lack of scatter thereby contributing a significant difference in dose calculation when using ACE. We believe that ACE calculation provides a more realistic isodose distribution than TG-43. We plan to further investigate the impact of heterogeneity correction on brachytherapy planning for a wide variety of clinical scenarios, include skin, cervix/uterus, prostate, and lung.

  16. Evaluation of aluminosilicate glass sintering during differential scanning calorimetry

    International Nuclear Information System (INIS)

    Souza, Juliana Pereira de

    2015-01-01

    In this work a difference in the baseline in differential scanning calorimetry analyses, observed in a work where aluminosilicate glasses microspheres containing Ho were studied for application in selective internal radiotherapy as hepatocellular carcinoma treatment, was studied. The glasses with nominal composition 53,7 SiO 2 .10,5 Al 2 O 3 . 35,8 MgO in %mol were produced from traditional melting. The first obtained were milled and sieved in the range of 45 a 63 μm. The material was used to produce glass microspheres by the gravitational fall method. The glass powder and the microspheres were characterized by X ray fluorescence spectrometry, laser diffraction, X ray diffraction, differential scanning calorimetry, differential thermal analysis, thermogravimetry, mass spectrometry, and scanning electron microscopy. After the thermal analyses, pellets were formed in the crucibles and were analyzed by scanning electron microscopy, X ray diffraction, and He pycnometry. The difference in the baseline was associated to the viscous flow sintering process and happens because of the decrease in the detected heat flow due to the sample shrinkage. Other events as concurrent crystallization with the sintering process were also studied. (author)

  17. Increased hippocampal excitability in the 3xTgAD mouse model for Alzheimer's disease in vivo.

    Directory of Open Access Journals (Sweden)

    Katherine E Davis

    Full Text Available Mouse Alzheimer's disease (AD models develop age- and region-specific pathology throughout the hippocampal formation. One recently established pathological correlate is an increase in hippocampal excitability in vivo. Hippocampal pathology also produces episodic memory decline in human AD and we have shown a similar episodic deficit in 3xTg AD model mice aged 3-6 months. Here, we tested whether hippocampal synaptic dysfunction accompanies this cognitive deficit by probing dorsal CA1 and DG synaptic responses in anaesthetized, 4-6 month-old 3xTgAD mice. As our previous reports highlighted a decline in episodic performance in aged control mice, we included aged cohorts for comparison. CA1 and DG responses to low-frequency perforant path stimulation were comparable between 3xTgAD and controls at both age ranges. As expected, DG recordings in controls showed paired-pulse depression; however, paired-pulse facilitation was observed in DG and CA1 of young and old 3xTgAD mice. During stimulus trains both short-latency (presumably monosynaptic: 'direct' and long-latency (presumably polysynaptic: 're-entrant' responses were observed. Facilitation of direct responses was modest in 3xTgAD animals. However, re-entrant responses in DG and CA1 of young 3xTgAD mice developed earlier in the stimulus train and with larger amplitude when compared to controls. Old mice showed less DG paired-pulse depression and no evidence for re-entrance. In summary, DG and CA1 responses to low-frequency stimulation in all groups were comparable, suggesting no loss of synaptic connectivity in 3xTgAD mice. However, higher-frequency activation revealed complex change in synaptic excitability in DG and CA1 of 3xTgAD mice. In particular, short-term plasticity in DG and CA1 was facilitated in 3xTgAD mice, most evidently in younger animals. In addition, re-entrance was facilitated in young 3xTgAD mice. Overall, these data suggest that the episodic-like memory deficit in 3xTgAD mice

  18. Recombinant TgHSP70 Immunization Protects against Toxoplasma gondii Brain Cyst Formation by Enhancing Inducible Nitric Oxide Expression

    Directory of Open Access Journals (Sweden)

    Neide M. Silva

    2017-04-01

    Full Text Available Toxoplasma gondii is known to cause congenital infection in humans and animals and severe disease in immunocompromised individuals; consequently development of vaccines against the parasite is highly necessary. Under stress conditions, T. gondii expresses the highly immunogenic heat shock protein 70 (TgHSP70. Here, we assessed the protective efficacy of rTgHSP70 immunization combined with Alum in oral ME-49 T. gondii infection and the mechanisms involved on it. It was observed that immunized mice with rTgHSP70 or rTgHSP70 adsorbed in Alum presented a significantly reduced number of cysts in the brain that was associated with increased iNOS+ cell numbers in the organ, irrespective the use of the adjuvant. Indeed, ex vivo experiments showed that peritoneal macrophages pre-stimulated with rTgHSP70 presented increased NO production and enhanced parasite killing, and the protein was able to directly stimulate B cells toward antibody producing profile. In addition, rTgHSP70 immunization leads to high specific antibody titters systemically and a mixed IgG1/IgG2a response, with predominance of IgG1 production. Nonetheless, it was observed that the pretreatment of the parasite with rTgHSP70 immune sera was not able to control T. gondii internalization and replication by NIH fibroblast neither peritoneal murine macrophages, nor anti-rTgHSP70 antibodies were able to kill T. gondii by complement-mediated lysis, suggesting that these mechanisms are not crucial to resistance. Interestingly, when in combination with Alum, rTgHSP70 immunization was able to reduce inflammation in the brain of infected mice and in parallel anti-rTgHSP70 immune complexes in the serum. In conclusion, immunization with rTgHSP70 induces massive amounts of iNOS expression and reduced brain parasitism, suggesting that iNOS expression and consequently NO production in the brain is a protective mechanism induced by TgHSP70 immunization, therefore rTgHSP70 can be a good candidate for

  19. Tissue transglutaminase (TG2) is involved in the resistance of cancer cells to the histone deacetylase (HDAC) inhibitor vorinostat.

    Science.gov (United States)

    Carbone, Carmine; Di Gennaro, Elena; Piro, Geny; Milone, Maria Rita; Pucci, Biagio; Caraglia, Michele; Budillon, Alfredo

    2017-03-01

    Vorinostat demonstrated preclinical and clinical efficacy in human cancers and is the first histone deacetylase inhibitor (HDACi) approved for cancer treatment. Tissue transglutaminase (TG2) is a multifunctional enzyme that catalyzes a Ca 2+ dependent transamidating reaction resulting in covalent cross-links between proteins. TG2 acts also as G-protein in trans-membrane signaling and as a cell surface adhesion mediator. TG2 up-regulation has been demonstrated in several cancers and its expression levels correlate with resistance to chemotherapy and metastatic potential. We demonstrated that the anti-proliferative effect of the HDACi vorinostat is paralleled by the induction of TG2 mRNA and protein expression in cancer cells but not in ex vivo treated peripheral blood lymphocytes. This effect was also shared by other pan-HDACi and resulted in increased TG2 transamidating activity. Notably, high TG2 basal levels in a panel of cancer cell lines correlated with lower vorinostat antiproliferative activity. Notably, in TG2-knockdown cancer cells vorinostat anti-proliferative and pro-apoptotic effects were enhanced, whereas in TG2-full-length transfected cells were impaired, suggesting that TG2 could represent a mechanism of intrinsic or acquired resistance to vorinostat. In fact, co-treatment of tumor cells with inhibitors of TG2 transamidating activity potentiated the antitumor effect of vorinostat. Moreover, vorinostat-resistant MCF7 cells selected by stepwise increasing concentrations of the drug, significantly overexpressed TG2 protein compared to parental cells, and co-treatment of these cells with TG2 inhibitors reversed vorinostat-resistance. Taken together, our data demonstrated that TG2 is involved in the resistance of cancer cells to vorinostat, as well as to other HDACi.

  20. WE-PIS-Exhibit Hall-01: Tools for TG-142 Linac Imaging QA II

    Energy Technology Data Exchange (ETDEWEB)

    Childress, N [Mobius Medical Management, LLC,, Houston, TX (United States); Murray, B [ZapIT Medical, Dublin, OH (Ireland)

    2014-06-15

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical “hands-on” information about the equipment and software systems that we use in our clinics. The therapy topic this year is solutions for TG-142 recommendations for linear accelerator imaging QA. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Using DoseLab to Perform TG-142 Imaging QA The goals of this session will be to present a clinical overview of acquiring images for TG-142 Imaging QA, as well as analyzing and evaluating results using DoseLab software. DoseLab supports planar imaging QA analysis using almost any QA phantom provided by numerous vendors. General advantages and disadvantages of selecting each of these phantoms will be briefly summarized. Best practices for selecting image acquisition parameters will be presented. A demonstration of using DoseLab software to perform a series of TG-142 tests will be performed. We will disuss why DoseLab uses its own set of imaging QA formulas, and why imaging QA measurement values of the same nominal properties will vary between TG- 142 software packages. Because TG-142 does not specify baseline and tolerance values for imaging QA, the presentation will recommend performing the manufacturer's acceptance test procedure to validate the equipment is functioning correctly. Afterwards, results can be obtained using the clinic's selected set of phantoms, image acquisition parameters, and TG-142 software to set proper baseline values. This presentation will highlight the reasons why comparing imaging QA results can be trickier than comparing linear accelerator treatment results and what physicists should keep in mind when comparing imaging QA results for different machines. Physicists are often unsure of the next step when there is an issue discovered during Imaging QA. Therefore, a few common examples

  1. WE-PIS-Exhibit Hall-01: Tools for TG-142 Linac Imaging QA II

    International Nuclear Information System (INIS)

    Childress, N; Murray, B

    2014-01-01

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical “hands-on” information about the equipment and software systems that we use in our clinics. The therapy topic this year is solutions for TG-142 recommendations for linear accelerator imaging QA. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Using DoseLab to Perform TG-142 Imaging QA The goals of this session will be to present a clinical overview of acquiring images for TG-142 Imaging QA, as well as analyzing and evaluating results using DoseLab software. DoseLab supports planar imaging QA analysis using almost any QA phantom provided by numerous vendors. General advantages and disadvantages of selecting each of these phantoms will be briefly summarized. Best practices for selecting image acquisition parameters will be presented. A demonstration of using DoseLab software to perform a series of TG-142 tests will be performed. We will disuss why DoseLab uses its own set of imaging QA formulas, and why imaging QA measurement values of the same nominal properties will vary between TG- 142 software packages. Because TG-142 does not specify baseline and tolerance values for imaging QA, the presentation will recommend performing the manufacturer's acceptance test procedure to validate the equipment is functioning correctly. Afterwards, results can be obtained using the clinic's selected set of phantoms, image acquisition parameters, and TG-142 software to set proper baseline values. This presentation will highlight the reasons why comparing imaging QA results can be trickier than comparing linear accelerator treatment results and what physicists should keep in mind when comparing imaging QA results for different machines. Physicists are often unsure of the next step when there is an issue discovered during Imaging QA. Therefore, a few common examples

  2. The diagnostic value of thyroglobulin concentration in fine-needle aspiration of the cervical lymph nodes in patients with differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Mikosinski, S.; Oszukowska, L.; Makarewicz, J.; Adamczewski, Z.; Lewinski, A.; Pomorski, L.; Sporny, S.

    2006-01-01

    Introduction: Recurrent differentiated thyroid cancer generally occurs first in the neck. Ultrasound is sensitive in detecting enlarged cervical lymph nodes but is not specific enough. Ultrasound-guided fine-needle biopsy increases the specificity but still may fail to detect a recurrence of the disease in the cystic metastatic lymph nodes. The aim of the study was to estimate the value of Tg concentration in the needle washout after fine-needle aspiration of suspicious lymph nodes. Material and methods: The 105 patients studied had presented one or more enlarged suspicious cervical lymph nodes. All had undergone total thyroidectomy and 131I ablative therapy. Serum thyroglobulin (Tg) concentration was within the 0.15 - 711.5 ng/ml range (mean 22.24 ng/ml) and Tg recovery range 94 - 100%. The positive Tg washout concentration cut-off value was established as equal to the mean plus two standard deviations of the Tg washout concentration of patients with negative cytology. Results: Lymph node involvement was diagnosed by cytology in 15 patients and in 28 lymph nodes. Positive Tg washout concentration was found in 22 patients and in 48 lymph nodes. All the lymph nodes which turned out to have positive cytology had a positive Tg washout concentration. All lymph nodes with positive cytology were positive in pathology. Seven patients and 20 lymph nodes with negative cytology were positive in the Tg washout concentration test. All but one patients and all but two lymph nodes with a positive Tg washout concentration had positive pathology. Conclusions: 1. Ultrasound-guided fine-needle biopsy is not sensitive enough to detect all metastatic lymph nodes. 2. The Tg washout concentration test is 100% sensitive in the detection of metastatic lymph nodes. 3. Cytology in ultrasound- guided fine-needle biopsy is 100% specific. 4. The Tg washout concentration test carries a risk of false-positive results. 5. Both methods should be used for early detection of metastatic lymph nodes

  3. Thyroglobulin measurement using highly sensitive assays in patients with differentiated thyroid cancer:

    DEFF Research Database (Denmark)

    Giovanella, Luca; Clark, Penelope M; Chiovato, Luca

    2014-01-01

    Differentiated thyroid cancer (DTC) is the most common endocrine cancer and its incidence has increased in recent decades. Initial treatment usually consists of total thyroidectomy followed by ablation of thyroid remnants by iodine-131. As thyroid cells are assumed to be the only source...... at low concentrations now allows detection of very low Tg concentrations reflecting minimal amounts of thyroid tissue without the need for TSH stimulation. Use of these highly sensitive Tg assays has not yet been incorporated into clinical guidelines but they will, we believe, be used by physicians...

  4. Synthesis, characterization and thermal behavior of rare earth amido sulfonates

    International Nuclear Information System (INIS)

    Luiz, Jose Marques; Nunes, Ronaldo Spezia; Matos, Jivaldo do Rosario

    2013-01-01

    Hydrated compounds prepared in aqueous solution by reaction between amidosulfonic acid [H 3 NSO 3 ] and suspensions of rare earth hydroxycarbonates [Ln 2 (OH) x (CO 3 ) y .zH 2 O] were characterized by elemental analysis (% Ln, % N and % H), infrared spectroscopy (FTIR) and thermogravimetry (TG). The compounds presented the stoichiometry Ln(NH 2 SO 3 ) 3 .xH 2 O (where x = 1, 5, 2.0 or 3.0). The IR spectra showed absorptions characteristic of H 2 O molecules and NH 2 SO 3 groups. Degree of hydration, thermal decomposition steps and formation of stable intermediates of the type [Ln 2 (SO 4 ) 3 ] and (Ln 2 O 2 SO 4 ), besides formation of their oxides, was determined by thermogravimetry. (author)

  5. Correlation between serum thyroglobulin levels and whole body scans in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Hristova, N.; Piperkova, E.; Sergieva, S.; Tsingilev, D.; Fanariotov, D.; Kirilova, B.; Dimitrova, M.

    1999-01-01

    Postoperative follow-up study of patients with differentiated thyroid carcinoma (DTC) is currently based on periodic whole body scan (WBS) and serum thyroglobulin (Tg) assessment. The correlation between Tg levels measured and WB scans of 84 DTC patients is investigated. WBS are performed on a rotation gamma camera DIACAM (Siemens) at 48 and 72 hours after per os administration of 185-222 MBq 131 I. The levels of Tg are determined by IRMA method and kits of BYK, Germany. Normal Tg values are obtained at a control group of 27 patients free of thyroid disease. Increased Tg levels are found at 2 cases (4%) of the group of 50 patients with total thyroidectomy given 131 I without any evidence of recurrences or metastases. At the third group consisting of 18 patients with total thyroidectomy, following 131 I therapy and recurrences and/or metastases, increased Tg values were obtained in 8 cases or 44.4%. Also increased Tg levels were obtained at 4 from 16 patients (25%) subjected to total thyroidectomy but with a residual thyroid tissue proved by scintigraphy. In conclusion, a combination of both methods should be applied for improving the diagnostic and therapeutic results at the postoperative control of DTC patients

  6. Mullite fibres preparation by aqueous sol-gel process and activation energy of mullitization

    International Nuclear Information System (INIS)

    Tan Hongbin; Ding Yaping; Yang Jianfeng

    2010-01-01

    Mullite fibres were prepared by sol-gel process using aluminum carboxylates (ACs) and silica sol. ACs was synthesized from dissolving aluminum powder in a mixture of formic acid and oxalic acid using aluminum chloride hexahydrate as catalyst. A molar ratio of 1:2:1 for aluminum, formic acid and oxalic acid was optimized to obtain clear solution and viscous ACs sol for fibres synthesis. Thermogravimetry-differential scanning calorimetry (TG-DSC), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis were used to characterize the properties of the gel and ceramic fibres. The gel fibres completely transformed to mullite at 1200 o C, with a smooth surface and uniform diameter. The activation energy for mullite formation in precursor gel fibres was determined by means of differential thermal analysis. The value obtained, E a = 741.4 kJ/mol, was lower than most data reported in the literatures, which was attributed to the silica-alumina micro-phase separation when organic acids decomposed during gel fibres heating.

  7. Nanobarium Titanate As Supplement To Accelerate Plastic Waste Biodegradation By Indigenous Bacterial Consortia

    Science.gov (United States)

    Kapri, Anil; Zaidi, M. G. H.; Goel, Reeta

    2009-06-01

    Plastic waste biodegradation studies have seen several developmental phases from the discovery of potential microbial cultures, inclusion of photo-oxidizable additives into the polymer chain, to the creation of starch-embedded biodegradable plastics. The present study deals with the supplementation of nanobarium titanate (NBT) in the minimal broth in order to alter the growth-profiles of the Low-density polyethylene (LDPE) degrading consortia. The pro-bacterial influence of the nanoparticles could be seen by substantial changes such as shortening of the lag phase and elongation of the exponential as well as stationary growth phases, respectively, which eventually increase the biodegradation efficiency. In-vitro biodegradation studies revealed better dissolution of LDPE in the presence of NBT as compared to control. Significant shifting in λ-max values was observed in the treated samples through UV-Vis spectroscopy, while Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis (TG-DTG-DTA) further confirmed the breakage and formation of bonds in the polymer backbone. Therefore, this study suggests the implementation of NBT as nutritional additive for plastic waste management through bacterial growth acceleration.

  8. Fabrication and Intermolecular Interactions of Silk Fibroin/Hydroxybutyl Chitosan Blended Nanofibers

    Directory of Open Access Journals (Sweden)

    Xiu-Mei Mo

    2011-03-01

    Full Text Available The native extracellular matrix (ECM is composed of a cross-linked porous network of multifibril collagens and glycosaminoglycans. Nanofibrous scaffolds of silk fibroin (SF and hydroxybutyl chitosan (HBC blends were fabricated using 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP and trifluoroacetic acid (TFA as solvents to biomimic the native ECM via electrospinning. Scanning electronic microscope (SEM showed that relatively uniform nanofibers could be obtained when 12% SF was blended with 6% HBC at the weight ratio of 50:50. Meanwhile, the average nanofibrous diameter increased when the content of HBC in SF/HBC blends was raised from 20% to 100%. Fourier transform infrared spectra (FTIR and 13C nuclear magnetic resonance (NMR showed SF and HBC molecules existed in hydrogen bonding interactions but HBC did not induce conformation of SF transforming from random coil form to β-sheet structure. X-ray diffraction (XRD confirmed the different structure of SF/HBC blended nanofibers from both SF and HBC. Thermogravimetry-Differential thermogravimetry (TG-DTG results demonstrated that the thermal stability of SF/HBC blend nanofibrous scaffolds was improved. The results indicated that the rearrangement of HBC and SF molecular chain formed a new structure due to stronger hydrogen bonding between SF and HBC. These electrospun SF/HBC blended nanofibers may provide an ideal tissue engineering scaffold and wound dressing.

  9. Open TG-GATEs: a large-scale toxicogenomics database

    Science.gov (United States)

    Igarashi, Yoshinobu; Nakatsu, Noriyuki; Yamashita, Tomoya; Ono, Atsushi; Ohno, Yasuo; Urushidani, Tetsuro; Yamada, Hiroshi

    2015-01-01

    Toxicogenomics focuses on assessing the safety of compounds using gene expression profiles. Gene expression signatures from large toxicogenomics databases are expected to perform better than small databases in identifying biomarkers for the prediction and evaluation of drug safety based on a compound's toxicological mechanisms in animal target organs. Over the past 10 years, the Japanese Toxicogenomics Project consortium (TGP) has been developing a large-scale toxicogenomics database consisting of data from 170 compounds (mostly drugs) with the aim of improving and enhancing drug safety assessment. Most of the data generated by the project (e.g. gene expression, pathology, lot number) are freely available to the public via Open TG-GATEs (Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System). Here, we provide a comprehensive overview of the database, including both gene expression data and metadata, with a description of experimental conditions and procedures used to generate the database. Open TG-GATEs is available from http://toxico.nibio.go.jp/english/index.html. PMID:25313160

  10. Observation of changes of serum leptin and lipid (TG and TC) levels in patients with graves' disease

    International Nuclear Information System (INIS)

    Wang Zhaobao; Cheng Guanghua

    2008-01-01

    Objective: To investigate the clinical significance of changes of serum leptin (with RIA) and lipid (TG and TC) (with biochemistry) levels in patients with Graves' disease. Methods: Serum Leptin, TG and TC levels were determined in 29 patients with Graves' disease both before and after treatment as well as in 30 controls. Results: Before treatment, serum Leptin, TG and TC levels in the patients were significantly lower than those in the controls. After treatment, serum Leptin, TG and TC levels increased and were significantly higher than those before treatment and were not much different from those in controls. Conclusion: The changes of serum Leptin, TG and TC levels may be of value for outcome prediction in patients with Graves' disease. (authors)

  11. Empiric 131I treatment of high thyroglobulin levels in differentiated thyroid carcinoma after remnant ablation

    International Nuclear Information System (INIS)

    Kalender, E.; Elboga, U.; Celen, Y.; Demir, H.; Yilmaz, M.; Sahin, E.

    2015-01-01

    Full text of publication follows. Objective: serum thyroglobulin (Tg) measurements are usually the best marker of residual or metastatic disease after the treatment of differentiated thyroid carcinoma (DTC). It is not rare to find patients with detectable serum Tg levels after ablative 131 I treatment (AIT). The objective of this study is to establish the efficacy of empiric 131 I treatment (EIT) given for patients whose Tg levels remained high after AIT. Materials and methods: 28 patients (23 women, 5 men; mean age 47.4 ± 16.8) without distant metastasis, who were treated empirically for high Tg levels after AIT in our clinic were studied retrospectively. In all patients stimulated Tg levels before AIT (Tg I) and 6 months after AIT (Tg II) were measured. The Tg cutoff level for EIT was accepted 10 ng/ml. After EIT, post-therapeutic whole-body scintigraphy (PWBS) was performed to all patients. 18 F-FDG PET CT was performed to patients who had negative PWBS but continued high Tg II levels. Results: PWBS was positive in 14 patients (50%) and negative in 14 patients (50%). 14 patients did not respond to EIT (50%), and 14 patients (50%) responded to EIT at different rates. Eight patients (28.6%) responded to EIT completely, and 6 patients (21.4%) responded to EIT partially. Tg I was 60.7 ± 40 ng/ml and Tg II was 31 ± 20.4 ng/ml in responded patients. Tg I was 87.6 ± 96 ng/ml and Tg II was 114.3 ± 106 ng/ml in non-responding patients. 18 F-FDG PET CT was performed to 14 patients who had negative PWBS. 18 F-FDG PET CT was positive in 11 patients and negative in 3 patients. 18 F-FDG PET CT positive patients were referred to surgery. Conclusion: Our findings, suggested that the EIT is not beneficial in patients who have higher Tg II than Tg I and the cure rate is low in increasing Tg levels. The patients who have high Tg II but lower than Tg I can be treated empirically with 131 I. In these patients EIT may be beneficial. (authors)

  12. Spaceflight influences both mucosal and peripheral cytokine production in PTN-Tg and wild type mice.

    Directory of Open Access Journals (Sweden)

    Justin L McCarville

    Full Text Available Spaceflight is associated with several health issues including diminished immune efficiency. Effects of long-term spaceflight on selected immune parameters of wild type (Wt and transgenic mice over-expressing pleiotrophin under the human bone-specific osteocalcin promoter (PTN-Tg were examined using the novel Mouse Drawer System (MDS aboard the International Space Station (ISS over a 91 day period. Effects of this long duration flight on PTN-Tg and Wt mice were determined in comparison to ground controls and vivarium-housed PTN-Tg and Wt mice. Levels of interleukin-2 (IL-2 and transforming growth factor-beta1 (TGF-β1 were measured in mucosal and systemic tissues of Wt and PTN-Tg mice. Colonic contents were also analyzed to assess potential effects on the gut microbiota, although no firm conclusions could be made due to constraints imposed by the MDS payload and the time of sampling. Spaceflight-associated differences were observed in colonic tissue and systemic lymph node levels of IL-2 and TGF-β1 relative to ground controls. Total colonic TGF-β1 levels were lower in Wt and PTN-Tg flight mice in comparison to ground controls. The Wt flight mouse had lower levels of IL-2 and TGF-β1 compared to the Wt ground control in both the inguinal and brachial lymph nodes, however this pattern was not consistently observed in PTN-Tg mice. Vivarium-housed Wt controls had higher levels of active TGF-β1 and IL-2 in inguinal lymph nodes relative to PTN-Tg mice. The results of this study suggest compartmentalized effects of spaceflight and on immune parameters in mice.

  13. Utilización de técnicas acopladas de análisis térmico TG-DSC-QMSFTIR en la caracterización de arcillas y composiciones cerámicas utilizadas en la fabricación de baldosas cerámicas. Cuantificación de compuestos de carbono

    Directory of Open Access Journals (Sweden)

    Gómez, M. P.

    2007-10-01

    Full Text Available In this study, a work methodology has been developed for t evolved gas analysis (EGA in clay raw materials and ceramic compositions used in ceramic tile manufacture using coupled thermal analysis techniques (TG-DSC-QMS-FTIR. The different types of gases (CO2, CO, NOx, F, SOx evolving from these raw materials during a thermal cycle up to a peak temperature of 1200ºC were characterised. The possibility of using this calorimeter for the quantification of the CO2 gases evolving from the organic and inorganic carbon (carbonates present in the studied clay materials was also evaluated. The measurements were validated with different reference materials, and the results were compared with those obtained with other analysis techniques, such as thermogravimetry (TG, calcimetry, and coulometry. The thermal analysis technique (TG-DSC-QMS-FTIR is a suitable technique for analysing evolved gases with low uncertainties for carbon compounds quantification. Furthermore, the methodology allows the mineralogical origin identification of the elements present in the evolved gases.

    En el presente estudio se ha desarrollado una metodología de trabajo para el análisis de emisiones gaseosas (EGA en materias primas arcillosas y composiciones cerámicas utilizadas en la fabricación de baldosas cerámicas mediante técnicas acopladas de análisis térmico (TG-DSC-QMS-FTIR. Se caracterizaron los distintos tipos de emisiones (CO2, CO, NOx, F, SOx que se emiten durante un ciclo térmico hasta una temperatura máxima de 1200ºC. Asimismo, se evaluó la posibilidad de la utilización de la técnica para la cuantificación de dichas emisiones. En concreto se ha realizado la cuantificación de emisiones de CO2 procedentes de la presencia de carbono orgánico e inorgánico en materiales arcillosos. Se han validado las medidas con distintos materiales de referencia y se han comparado los resultados con los obtenidos con otras técnicas de análisis, tales como la

  14. TH-EF-BRC-00: TG-100 Workshop

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-06-15

    This Hands-on Workshop will be focused on providing participants with experience with the principal tools of TG 100 and hence start to build both competence and confidence in the use of risk-based quality management techniques. The three principal tools forming the basis of TG 100’s risk analysis: Process mapping, Failure-Modes and Effects Analysis and fault-tree analysis will be introduced with a 5 minute refresher presentation and each presentation will be followed by a 30 minute small group exercise. An exercise on developing QM from the risk analysis follows. During the exercise periods, participants will apply the principles in 2 different clinical scenarios. At the conclusion of each exercise there will be ample time for participants to discuss with each other and the faculty their experience and any challenges encountered. Learning Objectives: To review the principles of Process Mapping, Failure Modes and Effects Analysis and Fault Tree Analysis. To gain familiarity with these three techniques in a small group setting. To share and discuss experiences with the three techniques with faculty and participants. Director, TreatSafely, LLC. Director, Center for the Assessment of Radiological Sciences. Occasional Consultant to the IAEA and Varian.

  15. TH-EF-BRC-00: TG-100 Workshop

    International Nuclear Information System (INIS)

    2016-01-01

    This Hands-on Workshop will be focused on providing participants with experience with the principal tools of TG 100 and hence start to build both competence and confidence in the use of risk-based quality management techniques. The three principal tools forming the basis of TG 100’s risk analysis: Process mapping, Failure-Modes and Effects Analysis and fault-tree analysis will be introduced with a 5 minute refresher presentation and each presentation will be followed by a 30 minute small group exercise. An exercise on developing QM from the risk analysis follows. During the exercise periods, participants will apply the principles in 2 different clinical scenarios. At the conclusion of each exercise there will be ample time for participants to discuss with each other and the faculty their experience and any challenges encountered. Learning Objectives: To review the principles of Process Mapping, Failure Modes and Effects Analysis and Fault Tree Analysis. To gain familiarity with these three techniques in a small group setting. To share and discuss experiences with the three techniques with faculty and participants. Director, TreatSafely, LLC. Director, Center for the Assessment of Radiological Sciences. Occasional Consultant to the IAEA and Varian.

  16. In vivo determination of triglyceride (TG) secretion in rats fed different dietary saturated fats using [2-3H]-glycerol

    International Nuclear Information System (INIS)

    Lai, H.C.; Yang, H.; Lasekan, J.; Clayton, M.; Ney, D.M.

    1990-01-01

    Male, Sprague-Dawley rats (154±1 g) were fed diets containing 2% corn oil (CO) + 14% butterfat (BF), beef tallow (BT), olive oil (OO) or coconut oil (CN) vs a 16% CO control diet for 5 weeks. Changes in plasma TG specific activity (dpm/mg TG) were determined in individual unanesthetized rats after injection of 100 μCi [2- 3 H]-glycerol via a carotid cannula. Fractional rate constants were obtained using a 2-compartment model and nonlinear regression analysis. Results demonstrated no difference in the fractional rate constants among dietary groups; but, differences in the rates of hepatic TG secretion were noted. Rats fed BT showed a higher rate of hepatic TG secretion than rats fed CO. Rats fed BF, OO or CN showed somewhat higher rates of hepatic TG secretion than CO. VLDL TG, phospholipid, and apolipoprotein B and E levels were higher with saturated fats vs CO. The data suggest that the higher plasma TG levels noted in response to feeding saturated fats vs corn oil can be explained, in part, by an increased flux of hepatic TG secretion

  17. Heavy fuel oil pyrolysis and combustion: kinetics and evolved gases investigated by TGA-FTIR

    KAUST Repository

    Abdul Jameel, Abdul Gani

    2017-08-24

    Heavy fuel oil (HFO) obtained from crude oil distillation is a widely used fuel in marine engines and power generation technologies. In the present study, the pyrolysis and combustion of a Saudi Arabian HFO in nitrogen and in air, respectively, were investigated using non-isothermal thermo-gravimetric analysis (TGA) coupled with a Fourier-transform infrared (FTIR) spectrometer. TG and DTG (differential thermo-gravimetry) were used for the kinetic analysis and to study the mass loss characteristics due to the thermal degradation of HFO at temperatures up to 1000°C and at various heating rates of 5, 10 and 20°C/min, in air and N2 atmospheres. FTIR analysis was then performed to study the composition of the evolved gases. The TG/DTG curves during HFO combustion show the presence of three distinct stages: the low temperature oxidation (LTO); fuel decomposition (FD); and high temperature oxidation (HTO) stages. The TG/DTG curves obtained during HFO pyrolysis show the presence of two devolatilization stages similar to that seen in the LTO stage of HFO combustion. Apart from this, the TG/DTG curves obtained during HFO combustion and pyrolysis differ significantly. Kinetic analysis was also performed using the distributed activation energy model, and the kinetic parameter (E) was determined for the different stages of HFO combustion and pyrolysis processes, yielding a good agreement with the measured TG profiles. FTIR analysis showed the signal of CO2 as approximately 50 times more compared to the other pollutant gases under combustion conditions. Under pyrolytic conditions, the signal intensity of alkane functional groups was the highest followed by alkenes. The TGA-FTIR results provide new insights into the overall HFO combustion processes, which can be used to improve combustor designs and control emissions.

  18. Experimental design applied optimization of a state in epoxy clay dispersion

    International Nuclear Information System (INIS)

    Paz, Juliana D'Avila; Bertholdi, Jonas; Folgueras, Marilena Valadares; Pezin, Sergio Henrique; Coelho, Luiz Antonio Ferreira

    2010-01-01

    This paper presents some analysis showed that the exfoliation / intercalation of a montmorillonite clay in epoxy resin such as viscosity, X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetry (TG). Increasing the viscosity of epoxy resin diglycidyl ether bisphenol A with the addition of clay associated with the sonification system at the time of dispersion is a good indication of exfoliation. The X-ray diffraction already cured composite shows a decrease of crystallinity of clay and EDS microanalysis of SEM, non-uniform dispersion of clay in epoxy resin. Thermal analysis TG composite clay / epoxy shows an increase in thermal stability relative to pure epoxy. (author)

  19. Experimental design applied optimization of a state in epoxy clay dispersion; Planejamento de experimentos aplicado a otimizacao do estado de dispersao de argilas em epoxi

    Energy Technology Data Exchange (ETDEWEB)

    Paz, Juliana D' Avila; Bertholdi, Jonas; Folgueras, Marilena Valadares; Pezin, Sergio Henrique; Coelho, Luiz Antonio Ferreira, E-mail: julianadpaz@yahoo.com.b [Universidade do Estado de Santa Catarina (UDESC), Joinville, SC (Brazil). Centro de Ciencias Tecnologicas

    2010-07-01

    This paper presents some analysis showed that the exfoliation / intercalation of a montmorillonite clay in epoxy resin such as viscosity, X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetry (TG). Increasing the viscosity of epoxy resin diglycidyl ether bisphenol A with the addition of clay associated with the sonification system at the time of dispersion is a good indication of exfoliation. The X-ray diffraction already cured composite shows a decrease of crystallinity of clay and EDS microanalysis of SEM, non-uniform dispersion of clay in epoxy resin. Thermal analysis TG composite clay / epoxy shows an increase in thermal stability relative to pure epoxy. (author)

  20. A Monte Carlo derived TG-51 equivalent calibration for helical tomotherapy

    International Nuclear Information System (INIS)

    Thomas, S.D.; Mackenzie, M.; Rogers, D.W.O.; Fallone, B.G.

    2005-01-01

    Helical tomotherapy (HT) requires a method of accurately determining the absorbed dose under reference conditions. In the AAPM's TG-51 external beam dosimetry protocol, the quality conversion factor, k Q , is presented as a function of the photon component of the percentage depth-dose at 10 cm depth, %dd(10) x , measured under the reference conditions of a 10x10 cm 2 field size and a source-to-surface distance (SSD) of 100 cm. The value of %dd(10) x from HT cannot be used for the determination of k Q because the design of the HT does not meet the following TG-51 reference conditions: (i) the field size and the practical SSD required by TG-51 are not obtainable and (ii) the absence of the flattening filter changes the beam quality thus affecting some components of k Q . The stopping power ratio is not affected because of its direct relationship to %dd(10) x . We derive a relationship for the Exradin A1SL ion chamber converting the %dd(10) x measured under HT 'reference conditions' of SSD=85 cm and a 5x10 cm 2 field-size [%dd(10) x[HTRef] ], to the dosimetric equivalent value under for TG-51 reference conditions [%dd(10) x[HTTG-51] ] for HT. This allows the determination of k Q under the HT reference conditions. The conversion results in changes of 0.1% in the value of k Q for our particular unit. The conversion relationship should also apply to other ion chambers with possible errors on the order of 0.1%

  1. Microstructure and mechanical properties of composite resins subjected to accelerated artificial aging.

    Science.gov (United States)

    dos Reis, Andréa Cândido; de Castro, Denise Tornavoi; Schiavon, Marco Antônio; da Silva, Leandro Jardel; Agnelli, José Augusto Marcondes

    2013-01-01

    The aim of this study was to investigate the influence of accelerated artificial aging (AAA) on the microstructure and mechanical properties of the Filtek Z250, Filtek Supreme, 4 Seasons, Herculite, P60, Tetric Ceram, Charisma and Filtek Z100. composite resins. The composites were characterized by Fourier-transform Infrared spectroscopy (FTIR) and thermal analyses (Differential Scanning Calorimetry - DSC and Thermogravimetry - TG). The microstructure of the materials was examined by scanning electron microscopy. Surface hardness and compressive strength data of the resins were recorded and the mean values were analyzed statistically by ANOVA and Tukey's test (α=0.05). The results showed significant differences among the commercial brands for surface hardness (F=86.74, p<0.0001) and compressive strength (F=40.31, p<0.0001), but AAA did not affect the properties (surface hardness: F=0.39, p=0.53; compressive strength: F=2.82, p=0.09) of any of the composite resins. FTIR, DSC and TG analyses showed that resin polymerization was complete, and there were no differences between the spectra and thermal curve profiles of the materials obtained before and after AAA. TG confirmed the absence of volatile compounds and evidenced good thermal stability up to 200 °C, and similar amounts of residues were found in all resins evaluated before and after AAA. The AAA treatment did not significantly affect resin surface. Therefore, regardless of the resin brand, AAA did not influence the microstructure or the mechanical properties.

  2. Clinical significance of thyroglobulin autoantibodies enhancement in patients with differentiated thyroid cancer after thyroidectomy and radioiodine therapy

    Directory of Open Access Journals (Sweden)

    N V Severskaya

    2013-09-01

    Full Text Available Purpose: to evaluate the clinical utility of antithyroglobulin antibodies (TgAb as a tumor marker in patients with differentiated thyroid cancer (DTC after thyroidectomy and radioiodine ablation. Patients and methods. From 345 consecutive DTC patients after thyroidectomy and radioiodine ablation we select ed 148 patients with elevated TgAb level (with distant metastasis n = 93, without distant metastasis n = 55. Serum TgAb concentration was measured before radioiodine ablation and then every time before 131I treatment (RIT or diagnostic 131I whole body scanning (WBS. Results were compared with serum thyroglobulin (Tg concentration, neck echography, lung and bone roentgenography and 131I WBS findings. Results. TgAb level was elevated in 21% DTC patients before 131I ablation. The other 22% with initially normal TgAb displayed their rising during followup. In absence of distant metastasis TgAb declined after 1 st–2 nd cycle of RIT (an average 8.9 months after 131I ablation. Persistance or rising of TgAb in the longer term was associated with detectable thyroid remnant, residual tumor or metastatic lymph nodes. In case of negative TgAb status after sugery an increase of TgAb during first 3–6 months after ablation indicated mostly a response to the rise of Tg antigen secondary to 131I ablation. A rise TgAb in the longer term (after 3rd–5th cycles of RIT indicated to residual or recurrent disease in 86% cases. In patients with distant metastasis there were no correlation between change in TgAb concentration and clinical sta tus, including the rate of regression of metastatic disease. But in case of low or undetectable Tg and permanent high TgAb level only TgAb indicated the presence of disease. Conclusion: persistence or rising TgAb in longer term after 131I ablation can serve as surrogate tumor marker of per sistent or recurrent disease. It is critical to measure TgAb concentration, especially in patients with low or unde tectable Tg, because

  3. Characterization of sugar cane bagasse ash as raw material for the production of ceramics

    International Nuclear Information System (INIS)

    Fredericci, C.; Indelicato, R.L.; Ferreira Neto, J.B.; Ribeiro, T.R.; Landgraf, F.J.G.; Silva, G.F.B. Lenz e

    2012-01-01

    The aim of this paper was to analyze the sugar cane bagasse ash from three Sugar and Alcohol Plant of the State of Sao Paulo - Brazil. We intend to show the discrepancies between them, so that this raw material could be used with greater quality control in ceramic industries. The bagasse were analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and scanning electron microscopy. The ashes were analyzed by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive spectroscopy, and granulometric separation. The results indicated that the content of SiO 2 ranging from 50-80% by weight depends on the granulometry of the bagasse and on the region where it was collected. The analyses of X-ray diffraction indicate SiO 2 , Fe 2 O 3 , K 2 SO 4 and Mg 2 P 2 O 7 as crystalline phases. (author)

  4. Characterization of Al2O3-Co ceramic composite obtained by high energy mill

    International Nuclear Information System (INIS)

    Souza, J.L.; Assis, R.B. de; Carlos, E.M.; Oliveira, T.P.; Costa, F.A. da

    2014-01-01

    This work aims to characterize the ceramic composite Al 2 O3-Co obtained by high energy grinding. The composites were obtained by milling Al 2 O 3 and Co in a high energy mill at a speed of 400 rpm, in proportions of 5 to 20% Cobalt (Co). Ceramic composites with 5 and 20% cobalt were sintered at 1200 and 1300 ° C, with a 60-minute plateau and a heating rate of 10 ° C / min. The samples were characterized by X-ray diffraction (XRD), thermogravimetry and differential scanning calorimetry (TG / DSC) and scanning electron microscopy (SEM). The results show the significant effect of cobalt percentage and high energy grinding on the final properties of the Al 2 O 3 - Co ceramic composite, presenting satisfactory values for the composite with a 20% cobalt percentage, showing to be a promising material for application in cutting tools

  5. Flame Retardant and Antimicrobial Jute Textile Using Sodium Metasilicate Nonahydrate

    Directory of Open Access Journals (Sweden)

    Basak S.

    2014-06-01

    Full Text Available Flame retardant and antimicrobial functionalities were imparted in jute textile using sodium metasilicate nonahydrate (SMSN, commonly known as “water glass”. Sodium metasilicate nonahydrate (SMSN was applied in jute fabric in different concentration by padding method followed by drying. Flame retardancy of the fabric was evaluated by Limiting Oxygen Index (LOI and burning behaviour under vertical flammability tester including the char length. Burning rate was found to decrease by almost 10 times after an application of 2% SMSN compared to the control sample. Thermogravimetry (TG and differential scanning calorimetry (DSC analysis of both the control and treated jute fabrics were utilized to understand the mechanism of developed flame retardance in jute fabric. It was observed that the SMSN treated samples showed excellent antimicrobial property against both gram positive and gram negative bacteria. Antimicrobial properties of both the control and treated jute fabrics were also measured quantitatively.

  6. Study of the gamma radiation effect on lincomycin by two techniques thermal analysis and fourier transform infrared (FTIR)

    International Nuclear Information System (INIS)

    Al-Zier, A.; Al-Kassiri, H.; Al Aji, Z.

    1999-02-01

    Sample of Lincomycin were irradiated by means of gamma radiation ( 60 Co) at dose rate ca. (408 kGy/h) in the range (3, 5, 15, 20)kGy in presence of air. Samples were investigated using two techniques: Thermal analysis (Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG)) and Fourier Transform Infrared (FTIR). DSC purity study, which depends on Vant Hof equation, showed that the purity of Lincomycin reduced by means of gamma radiation. The purity of theses samples decreased by increasing the dose, and the purity of lincomycin was still above (99%) at dose (10 kGy). To follow up this effects, (FTIR) spectrums of these sample were recorded before and after irradiation. The two peaks at (1500 - 1750 Cm -1 ) which belong to amide group, and the peak at (1050 - 1100 Cm -1 ) which belongs to the S-C groups have reduced. (author)

  7. Study of the gamma radiation effect on the lincomycin by two techniques thermal analysis and fourier transform infrared (FTIR)

    International Nuclear Information System (INIS)

    Al-Zier, A.; Al-Kassiri, H.

    1999-01-01

    Sample of Lincomycin were irradiated by means of gamma radiation ( 60 Co) at dose rate ca. (408 kGy/h) in the range (3, 5, 15, 20)kGy in presence of air. Samples were investigated using two techniques: Thermal analysis (Differential Scanning Calorimetry (DSC) and Thermogravimetry (TG)) and Fourier Transform Infrared (FTIR). DSC purity study, which depends on Vant Hof equation, showed that the purity of Lincomycin reduced by means of gamma radiation. The purity of theses samples decreased by increasing the dose, and the purity of lincomycin was still above (99%) at dose (10 kGy). To follow up this effects, (FTIR) spectrums of these sample were recorded before and after irradiation. The two peaks at (1500 - 1750 Cm -1 ) which belong to amide group, and the peak at (1050 - 1100 Cm -1 ) which belongs to the S-C groups have reduced. (author)

  8. Thermal stability of segmented polyurethane elastomers reinforced by clay particles

    Directory of Open Access Journals (Sweden)

    Pavličević Jelena

    2009-01-01

    Full Text Available The aim of this work was to determine the influence of clay nanoparticles on thermal properties of segmented polyurethanes based on hexamethylene- diisocyanate, aliphatic polycarbonate diol and 1,4-butanediol as chain extender. The organically modified particles of montmorillonite and bentonite were used as reinforcing fillers. The structure of elastomeric materials was varied either by diol type or chain extender content. The ratio of OH groups from diol and chain extender (R was either 1 or 10. Thermal properties of prepared materials were determined using modulated differential scanning calorimetry (MDSC. Thermal stability of obtained elastomers has been studied by simultaneously thermogravimetry coupled with DSC. The glass transition temperature, Tg, of soft segments for all investigated samples was about -33°C. On the basis of DTG results, it was concluded that obtained materials were very stable up to 300°C.

  9. Investigation of optical properties and the photocatalytic activity of synthesized YbYO4 nanoparticles and YbVO4/NiWO4 nanocomposites by polymeric capping agents

    Science.gov (United States)

    Pourmasoud, Saeid; Sobhani-Nasab, Ali; Behpour, Mohsen; Rahimi-Nasrabadi, Mehdi; Ahmadi, Farhad

    2018-04-01

    YbVO4 nanoparticles YbVO4/NiWO4 nanocomposites were synthesized by simple and new method. The effect of various polymeric capping agents such as Tween 80, Tween 20 and PEG on the shape and size of YbVO4/NiWO4 nanocomposites were investigated. YbVO4/NiWO4 nanocomposites were analyzed through some techniques including, X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, vibrating sample magnetometer (VSM), thermogravimetry differential thermal analysis (TG-DTA), transmission electron microscopy (TEM), field emission electron microscopy (FESEM), ultraviolet-visible spectroscopy (UV-Vis), and energy-dispersive X-ray spectroscopy (EDX). This attempt is the first study on the photocatalytic performance of the YbVO4/NiWO4 nanocomposites in various conditions such as size of particles and kind of dyes (rhodamine B (Rh B), methylene blue (MB), methyl orange (MO), and phenol red (Ph R)), under visible light.

  10. The influence of temperature on the structure of Cd-doped ZnO nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoud, Waleed E., E-mail: w_e_mahmoud@yahoo.co [King Abdulaziz University, Faculty of Science, Physics Department, Jeddah (Saudi Arabia); Suez Canal University, Faculty of Science, Physics Department, Ismaillia (Egypt); Al-Ghamdi, A.A.; Al-Heniti, S.; Al-Ameer, S. [King Abdulaziz University, Faculty of Science, Physics Department, Jeddah (Saudi Arabia)

    2010-02-18

    A new and facile method has been used for preparation of CdZnO nanopowder. The prepared nanopowder was in the form of binary mixture of CdO and ZnO until annealing temperature 400 {sup o}C. When the annealing temperature increased above 400 {sup o}C the structure of the nanopowder was changed from binary mixture to a single hexagonal phase. Thermogravimetry/differential thermal analysis (TG-DTA), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to follow the change in the microstructure and morphology of the prepared nanopowders at different temperatures. The effect of calcination temperature on the growth dynamics of CdZnO nanopowder showed that the dynamic growth index was 1.13 below 400 {sup o}C and 0.5 above it. This indicates that the rate of the grain growth was very fast especially at calcination temperature range 400-750 {sup o}C.

  11. Preparation and Hydrogen Storage Properties of Mg-Rich Mg-Ni Ultrafine Particles

    Directory of Open Access Journals (Sweden)

    Jianxin Zou

    2012-01-01

    Full Text Available In the present work, Mg-rich Mg-Ni ultrafine powders were prepared through an arc plasma method. The phase components, microstructure, and hydrogen storage properties of the powders were carefully investigated. It is found that Mg2Ni and MgNi2 could be obtained directly from the vapor state reactions between Mg and Ni, depending on the local vapor content in the reaction chamber. A nanostructured MgH2 + Mg2NiH4 hydrogen storage composite could be generated after hydrogenation of the Mg-Ni ultrafine powders. After dehydrogenation, MgH2 and Mg2NiH4 decomposed into nanograined Mg and Mg2Ni, respectively. Thermogravimetry/differential scanning calorimetry (TG/DSC analyses showed that Mg2NiH4 phase may play a catalytic role in the dehydriding process of the hydrogenated Mg ultrafine particles.

  12. Discovery of protein profiles for differentiated thyroid cancer using SELDI TOF MS

    International Nuclear Information System (INIS)

    Yoon, Joon Kee; Lee, Myung Hoon; Joh, Chul Woo; Yoon, Seok Nam; Soh, Eui Young

    2003-01-01

    Low sensitivity of diagnostic whole body iodine scintigraphy and intermediate range of serum thyroglobulin (Tg) with or without anti-Tg antibody make it difficult to select the patients with differentiated thyroid cancer who need further treatment. Surfaced Enhanced Laser Desorption /Ionization - Time of Flight - Mass Spectrometry (SELDI TOF MS) is a useful method to evaluate cancer proteome, biomarkers and patterns of biomarkers. In this preliminary study, we evaluated and developed protein profiles for the discrimination between patients with differentiated thyroid cancer and non-cancer controls using SELDI technology. Serum samples from 10 healthy controls and from 14 patients with papillary thyroid cancer before thyroidectomy were analyzed by SELDI MS. Multiple protein peaks detected were analyzed by the computer software to develop a classifier for separating cancer patients form controls. The classifier was then challenged to 24 serum samples to determine the validity and accuracy of the classification system. All patients with papillary thyroid cancer had no other concomitant cancer or thyroiditis. Their serum Tg concentration was 55.8 (1.5 - 249.7) and 2 patients had extra-thyroidal extension. According to the SELDI analysis, protein peaks at 3696 Da, 4178 Da, and 8149 Da were more prominent in cancer patients than controls in various degrees. Among those, protein peak at 4178 Da was determined as classifier by computer software, and the sensitivity, specificity and accuracy for discrimination of cancer patients from controls was 92.9% (13/14), 90% (9/10) and 91.7% respectively. This preliminary study suggests that serum protein profiles of differentiated thyroid cancer can be used for differentiation between cancer patients and non-cancer controls. And further clinical studies in various test sets will offer useful information in selecting patients who require treatment

  13. Discovery of protein profiles for differentiated thyroid cancer using SELDI TOF MS

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Joon Kee; Lee, Myung Hoon; Joh, Chul Woo; Yoon, Seok Nam; Soh, Eui Young [College of Medicine, Univ. of Ajou, Suwon (Korea, Republic of)

    2003-07-01

    Low sensitivity of diagnostic whole body iodine scintigraphy and intermediate range of serum thyroglobulin (Tg) with or without anti-Tg antibody make it difficult to select the patients with differentiated thyroid cancer who need further treatment. Surfaced Enhanced Laser Desorption /Ionization - Time of Flight - Mass Spectrometry (SELDI TOF MS) is a useful method to evaluate cancer proteome, biomarkers and patterns of biomarkers. In this preliminary study, we evaluated and developed protein profiles for the discrimination between patients with differentiated thyroid cancer and non-cancer controls using SELDI technology. Serum samples from 10 healthy controls and from 14 patients with papillary thyroid cancer before thyroidectomy were analyzed by SELDI MS. Multiple protein peaks detected were analyzed by the computer software to develop a classifier for separating cancer patients form controls. The classifier was then challenged to 24 serum samples to determine the validity and accuracy of the classification system. All patients with papillary thyroid cancer had no other concomitant cancer or thyroiditis. Their serum Tg concentration was 55.8 (1.5 - 249.7) and 2 patients had extra-thyroidal extension. According to the SELDI analysis, protein peaks at 3696 Da, 4178 Da, and 8149 Da were more prominent in cancer patients than controls in various degrees. Among those, protein peak at 4178 Da was determined as classifier by computer software, and the sensitivity, specificity and accuracy for discrimination of cancer patients from controls was 92.9% (13/14), 90% (9/10) and 91.7% respectively. This preliminary study suggests that serum protein profiles of differentiated thyroid cancer can be used for differentiation between cancer patients and non-cancer controls. And further clinical studies in various test sets will offer useful information in selecting patients who require treatment.

  14. [Activation of endoplasmic reticulum stress and its effect on osteogenic differentiation induced by micropit/nanotube topography].

    Science.gov (United States)

    Shi, M Q; Song, W; Han, T X; Chang, B; Zhang, Y M

    2017-02-09

    Objective: To explore the activation of endoplasmic reticulum stress (ERS) in bone marrow mesenchymal stem cell (BMMSC) and its effect on osteogenic differentiation induced by micropit/nanotube topography (MNT), so as to provide guidance for the topography design of biomaterials. Methods: Four sample groups were fabricated: polishing control group (polished titanium, PT, no treatment), thapsigargin treatment (TG, 0.1 μmol/L TG treated for 9 h), MNT5 and MNT20 (anodized at 5 V and 20 V after acid etching). Scanning electron microscope (SEM) was used to observe the topography of Ti samples. The alkaline phosphatase (ALP) production, collagen secretion and extracellular matrix (ECM) mineralization of BMMSC (osteogenic induced for 7, 14 and 21 d) on Ti samples were detected to evaluate the osteogenic differentiation. After 12 h incubation, the shape and size of ER was examined using a transmission electron microscope (TEM), and ERS-related genes including immunoglobulin heavy chain binding protein (BiP), protein kinase RNA-like endoplasmic reticulum kinase (PERK) and activating transcription factor 4 (ATF4) were detected by quantitative real-time PCR (qRT-PCR). Results: After 7, 14 and 21 d of induction, the ALP production, collagen secretion and ECM mineralization in TG and MNT20 all significantly increased compared to PT ( P< 0.05). The cells grown on TG, MNT5 and MNT20 surfaces displayed gross distortions of the ER. Compared to PT, BiP, PERK, ATF4 mRNA expression in TG was respectively 1.87±0.10, 2.24±0.35, 1.85±0.14; BiP, ATF4 mRNA expression in MNT5 were respectively 1.27±0.09, 1.25±0.04; BiP, PERK, ATF4 mRNA expression in MNT20 were respectively 1.44±0.09, 2.40±0.60, 1.48±0.05 ( P< 0.05). Conclusions: MNT triggered different degree of ERS, and the activated ERS may promote MNT-induced osteogenic differentiation.

  15. A meta-analysis of adiponectin gene rs22411766 T>G polymorphism and ischemic stroke susceptibility

    Directory of Open Access Journals (Sweden)

    Xiuju Chen

    2016-01-01

    Full Text Available Several studies have investigated the correlation between adiponectin gene rs22411766 T>G polymorphism and ischemic stroke risk. However, the results were not conclusive with each other. Therefore, to overcome this obstacle, we performed this meta-analysis to further explicate the adiponectin gene rs22411766 T>G polymorphism and ischemic stroke susceptibility. Case-control or cohort studies focused on adiponectin gene rs22411766 T>G polymorphism and ischemic stroke risk were electronic searched in the databases of Medline, Pubmed, Cochrane library, Excerpta Medica database(EMBASE and China National Knowledge Infrastructure (CNKI. All the potentially relevant studies were included in this meta-analysis. The association between adiponectin gene rs22411766 T>G polymorphism and ischemic stroke was expressed by odds ratio with its confidence interval. Publication bias has been assessed by begg’s funnel plot. All the analyses have been performed by Revman 5.1 statistical software. Finally, a total of six studies with 1,345 cases and 1,421 controls were included in this meta-analysis. Our results demonstrated that there was a significant association between adiponectin gene rs22411766 T>G polymorphism and ischemic stroke risk (p<0.05. People with G single nucleotide of adiponectin gene have the increased risk of developing ischemic stroke compared to T single nucleotide.

  16. Solvent influence during radiation induced grafting of styrene in PVDF

    International Nuclear Information System (INIS)

    Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B.

    2013-01-01

    Radiation-induced grafting was studied to produce styrene grafted poly(vinylidene fluoride) (PVDF) membranes. PVDF films with 0.125 mm thickness were irradiated at doses between 5 and 20 kGy in the presence of styrene/N,N-dimethylformamide (DMF), styrene/acetone or styrene/toluene solutions (1:1, v/v) at dose rate of 5 kGy h -1 by simultaneous method, using gamma rays from a Co-60, under nitrogen atmosphere and at room temperature. The films were characterized before and after modification by grafting yield (GY %), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM and EDS), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). GY results shows that grafting increases with dose and toluene hinders the grafting, leading to a small GY comparing to DMF and acetone. It was possible to confirm the grafting of styrene by FT-IR due to the new characteristics peaks and by the TG and DSC due to changes in thermal behavior of the grafted material. SEM and EDS show surface and cross-section distribution of the grafting, which takes place on the surface and heterogeneously with toluene as solvent and homogeneously and penetrating into the inner layers of the matrix using DMF and acetone as solvent. (author)

  17. Preparation and Characterization of Pyrotechnics Binder-Coated Nano-Aluminum Composite Particles

    Science.gov (United States)

    Ye, Mingquan; Zhang, Shuting; Liu, Songsong; Han, Aijun; Chen, Xin

    2017-07-01

    The aim of this article is to protect the activity of nano-aluminum (Al) particles in solid rocket propellants and pyrotechnics. The morphology, structure, active aluminum content, and thermal and catalytic properties of the coated samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry-differential scanning calorimetry (TG-DSC), and oxidation-reduction titration methods. The results indicated that nano-Al particles could be effectively coated with phenolic resin (PF), fluororubber (Viton B), and shellac through a solvent/nonsolvent method. The energetic composite particles have core-shell structures and the thickness of the coating film is about 5-15 nm. Analysis of the active Al content revealed that Viton B coating had a much better protective effect. The TG-DSC results showed that the energy amount and energy release rate of PF-, Viton B-, and shellac-coated Al particles were larger than those of the raw nano-Al particles. The catalytic effects of coated Al particles on the thermal decomposition of ammonium perchlorate (AP) were better than those of raw nano-Al particles, and the effect of shellac-coated Al particles was significantly better than that of Viton B-coated Al particles.

  18. Preparation and Characterization of Modified Montmorillonite/Paraffin Phase Change Microcapsules for Energy Storage

    Directory of Open Access Journals (Sweden)

    LIN Sen

    2017-03-01

    Full Text Available The phase change microcapsules of modified montmorillonite/paraffin were prepared by Pickering emulsion method. Analytic techniques of optical microscopy, scanning electron microscopy(SEM, infrared spectroscopy(FTIR, differential scanning calorimetry(DSC and thermogravimetry(TG were utilized for characterizing chemical structure, morphology and thermal properties. Results show that modified montmorillonite as a new type wall material has excellent performance for protecting core material of paraffin. FTIR spectra of phase change of modified montmorillonite/paraffin microcapsules shows that their characteristic peaks match with corresponding peaks of pure paraffin and modified montmorillonite. DSC results indicate that modified montmorillonite/paraffin microcapsules have similar solid-liquid phase change temperature with pure paraffin. The phase transition enthalpy values of microcapsules with paraffin contents varying from 55% to 80% are 110.5-147.2J/g, indicating that microcapsules have excellent thermal storage performance and the phase change properties can be adjusted by changing contents of paraffin. TG results confirm that modified montmorillonite/paraffin microcapsules have outstanding thermal stability. The presented study indicates that modified montmorillonite is a suitable wall material for preparing paraffin microcapsule. Modified montmorillonite/paraffin microcapsules have advantages of low cost and high performance with a great application potential in the field of thermal storage.

  19. Solvent influence during radiation induced grafting of styrene in PVDF

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Henrique P.; Parra, Duclerc F.; Lugao, Ademar B., E-mail: hp.ferreira@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Radiation-induced grafting was studied to produce styrene grafted poly(vinylidene fluoride) (PVDF) membranes. PVDF films with 0.125 mm thickness were irradiated at doses between 5 and 20 kGy in the presence of styrene/N,N-dimethylformamide (DMF), styrene/acetone or styrene/toluene solutions (1:1, v/v) at dose rate of 5 kGy h{sup -1} by simultaneous method, using gamma rays from a Co-60, under nitrogen atmosphere and at room temperature. The films were characterized before and after modification by grafting yield (GY %), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM and EDS), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). GY results shows that grafting increases with dose and toluene hinders the grafting, leading to a small GY comparing to DMF and acetone. It was possible to confirm the grafting of styrene by FT-IR due to the new characteristics peaks and by the TG and DSC due to changes in thermal behavior of the grafted material. SEM and EDS show surface and cross-section distribution of the grafting, which takes place on the surface and heterogeneously with toluene as solvent and homogeneously and penetrating into the inner layers of the matrix using DMF and acetone as solvent. (author)

  20. Prevalence of iodine- and thyroglobulin-negative findings in differentiated thyroid cancer. A retrospective analysis of patients treated from 1961 to 1998 in a university hospital; Haeufigkeit lod- und hTG-negativer Befunde beim differenzierten Schilddruesenkarzinom. Eine retrospektive Analyse der von 1961 bis 1998 in einer Universitaetsklinik behandelten Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Klutmann, S.; Jenicke, L.; Geiss-Toenshoff, M.; Bohuslavizki, K.H.; Mester, J.; Clausen, M. [Universitaetskrankenhaus Eppendorf, Hamburg (Germany). Abt. fuer Nuklearmedizin

    2001-10-01

    Aim: The prevalence of iodine- and thyroglobulin-negative findings was evaluated in all patients with differentiated thyroid cancer (DTC) treated from 1961 until 1998 at the Department of Nuclear Medicine, University Hospital Hamburg-Eppendorf. Methods: A total of 490 patients with papillary thyroid cancer (PCA) and 242 patients with follicular thyroid cancer (FCA) were analyzed retrospectively. Patients were divided into four groups: 1: no recurrence, 2: recurrent disease, 3: primary metastatic/progressive disease and 4: inconclusive follow-up. Results of iodine scan, serum-TG, and additional imaging modalities as well as histology were compared in all patients. Results: 21/490 (4,3%) of patients with PCA and 16/242 (6,6%) with FCA suffered from recurrent disease. 62/490 (12,7%) of patients with PCA and 59/242 (24,4%) with FCA had primary metastatic/progressive disease. 12/21 patients with PCA and 12/16 with FCA showing up with recurrent disease had a negative iodinescan. 11/21 of patients with PCA and 4/16 with FCA and tumor recurrence had negative serum-TG levels. 14/62 patients with PCA and 14/59 with FCA presenting with primary metastatic/progressive disease had negative iodinescan. 14/62 patients with PCA and 6/59 with FCA had negative serum-TG. Conclusion: The prevalence of iodine-negative recurrent/metastatic disease is in accordance to the literature, whereas the prevalence of TG-negative recurrent/metastatic was noted higher than reported previously. Thus, the commonly used follow-up scheme of DTC is confirmed. However, iodine scan should be regularly performed in patients with high risk of recurrence. (orig.) [German] Ziel: Retrospektiv wurden alle von 1961 bis 1998 in der Abteilung fuer Nukleamedizin des Universitaetsklinikums Hamburg-Eppendorf behandelten Patienten mit einem differenzierten Schilddruesenkarzinom bezueglich des Anteils lod- und/oder hTG-negativer Rezidive analysiert. Methoden: Es wurden 490 Patienten mit einem papillaeren

  1. A Novel Form of Compensation in the Tg2576 Amyloid Mouse Model of Alzheimer's Disease.

    Science.gov (United States)

    Somogyi, Attila; Katonai, Zoltán; Alpár, Alán; Wolf, Ervin

    2016-01-01

    One century after its first description, pathology of Alzheimer's disease (AD) is still poorly understood. Amyloid-related dendritic atrophy and membrane alterations of susceptible brain neurons in AD, and in animal models of AD are widely recognized. However, little effort has been made to study the potential effects of combined morphological and membrane alterations on signal transfer and synaptic integration in neurons that build up affected neural networks in AD. In this study spatial reconstructions and electrophysiological measurements of layer II/III pyramidal neurons of the somatosensory cortex from wild-type (WT) and transgenic (TG) human amyloid precursor protein (hAPP) overexpressing Tg2576 mice were used to build faithful segmental cable models of these neurons. Local synaptic activities were simulated in various points of the dendritic arbors and properties of subthreshold dendritic impulse propagation and predictors of synaptic input pattern recognition ability were quantified and compared in modeled WT and TG neurons. Despite the widespread dendritic degeneration and membrane alterations in mutant mouse neurons, surprisingly little, or no change was detected in steady-state and 50 Hz sinusoidal voltage transfers, current transfers, and local and propagation delays of PSPs traveling along dendrites of TG neurons. Synaptic input pattern recognition ability was also predicted to be unaltered in TG neurons in two different soma-dendritic membrane models investigated. Our simulations predict the way how subthreshold dendritic signaling and pattern recognition are preserved in TG neurons: amyloid-related membrane alterations compensate for the pathological effects that dendritic atrophy has on subthreshold dendritic signal transfer and integration in layer II/III somatosensory neurons of this hAPP mouse model for AD. Since neither propagation of single PSPs nor integration of multiple PSPs (pattern recognition) changes in TG neurons, we conclude that AD

  2. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer's disease (3xTgAD) mice.

    Science.gov (United States)

    Knight, Elysse M; Brown, Timothy M; Gümüsgöz, Sarah; Smith, Jennifer C M; Waters, Elizabeth J; Allan, Stuart M; Lawrence, Catherine B

    2013-01-01

    Alzheimer's disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4-10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD.

  3. TH-A-BRC-01: AAPM TG-135U1 QA for Robotic Radiosurgery

    International Nuclear Information System (INIS)

    Dieterich, S.

    2016-01-01

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  4. TH-A-BRC-01: AAPM TG-135U1 QA for Robotic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Dieterich, S. [UC Davis Medical Center (United States)

    2016-06-15

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  5. Textural properties of low-fat set-type yoghurt depending on mTG addition

    Directory of Open Access Journals (Sweden)

    Lívia Darnay

    2016-07-01

    Full Text Available Our aim was to determine how 0.5-2 U/g non-inactivated mTG affects the pH development and apparent viscosity during fermentation. Furthermore we wished to examine how the enzyme addition could change protein structure, gel strength and sensory characteristics by healthy low-fat set-type yoghurt product. Therefore commercial mTG enzyme preparation was added in different concentrations (0.5-2.0 U/g, in 0.5 U/g steps to 1.5 % bovine milk simultaneously with DVS starter culture. Our study revealed that enzyme dosage (0.5-2 U/g protein had no impact on pH development and apparent viscosity during fermentation when manufacturing low-fat (1.5 % set-type yoghurt. The addition of mTG contributed to 38 % more whey retention with incorporation of β-casein, and caused 44 % higher gel strength up to a level of 1 U/g protein.

  6. Characterising the combustion behaviour of New Zealand coals by thermogravimetry

    Energy Technology Data Exchange (ETDEWEB)

    Benfell, K.E.; Beamish, B.B.; Rodgers, K.A. [University of Auckland, Auckland (New Zealand). Dept. of Geology

    1995-12-31

    Thirty-three New Zealand coals were subjected to thermogravimetric analysis (TG) and derivative thermogravimetric analysis (DTG) to evaluate the techniques` applicability to New Zealand coals. Generally, New Zealand sub-bituminous coals have lower burnout temperatures than bituminous coals. However, local and regional differences occur, where some sub-bituminous coals show both higher and lower char burnout temperatures than may be otherwise expected from their rank and T{sub 6} values (the peak temperature where the rate of weight loss of the sample is the greatest). There is a sizeable variations in the char burnout temperature (T{sub 8}) (465 to 636{degree}C) in coals with volatile matter contents above 40%, whereas coals with lower volatile contents have T{sub 8} values around 646{degree}C. The temperature of char burnout gives a better indication of combustion efficiency than rank or volatile matter content alone. Industrial operators could use this technique to provide an indication of burnout performance before a coal is purchased, assisting evaluation of the coal`s suitability for a particular usage. 10 refs., 4 figs., 3 tabs.

  7. Macrophage-mediated gliadin degradation and concomitant IL-27 production drive IL-10- and IFN-γ-secreting Tr1-like-cell differentiation in a murine model for gluten tolerance.

    Science.gov (United States)

    van Leeuwen, M A; Costes, L M M; van Berkel, L A; Simons-Oosterhuis, Y; du Pré, M F; Kozijn, A E; Raatgeep, H C; Lindenbergh-Kortleve, D J; van Rooijen, N; Koning, F; Samsom, J N

    2017-05-01

    Celiac disease is caused by inflammatory T-cell responses against the insoluble dietary protein gliadin. We have shown that, in humanized mice, oral tolerance to deamidated chymotrypsin-digested gliadin (CT-TG2-gliadin) is driven by tolerogenic interferon (IFN)-γ- and interleukin (IL)-10-secreting type 1 regulatory T-like cells (Tr1-like cells) generated in the spleen but not in the mesenteric lymph nodes. We aimed to uncover the mechanisms underlying gliadin-specific Tr1-like-cell differentiation and hypothesized that proteolytic gliadin degradation by splenic macrophages is a decisive step in this process. In vivo depletion of macrophages caused reduced differentiation of splenic IFN-γ- and IL-10-producing Tr1-like cells after CT-TG2-gliadin but not gliadin peptide feed. Splenic macrophages, rather than dendritic cells, constitutively expressed increased mRNA levels of the endopeptidase Cathepsin D; macrophage depletion significantly reduced splenic Cathepsin D expression in vivo and Cathepsin D efficiently degraded recombinant γ-gliadin in vitro. In response to CT-TG2-gliadin uptake, macrophages enhanced the expression of Il27p28, a cytokine that favored differentiation of gliadin-specific Tr1-like cells in vitro, and was previously reported to increase Cathepsin D activity. Conversely, IL-27 neutralization in vivo inhibited splenic IFN-γ- and IL-10-secreting Tr1-like-cell differentiation after CT-TG2-gliadin feed. Our data infer that endopeptidase mediated gliadin degradation by macrophages and concomitant IL-27 production drive differentiation of splenic gliadin-specific Tr1-like cells.

  8. Value of the Serum Thyroglobulin Level Alteration at the First High Dose Radioiodine Treatment in Patients with Differentiated Thyroid Carcinoma

    International Nuclear Information System (INIS)

    Nam, Hyun Yeol; Kim, In Joo; Kim, Yong Ki; Kim, Seong Jang; Jun, Sung Min; Kim, Bum Soo

    2009-01-01

    The purpose of this study was to evaluate if short-term serum thyroglobulin (Tg) elevation after radioiodine administration can predict successful radioiodine remnant ablation (RRA) and whether comparable RRA effectiveness is exhibited between a group administered with recombinant human thyrotropin (rhTSH) and a group experiencing thyroid hormone withdrawal (THW), in preparation for RRA. A retrospective chart review was performed on 39 patients in the rhTSH group and 46 patients in the THW group. They were treated for differentiated thyroid carcinoma by total or near total thyroidectomy, and referred for RRA between 2003 and 2006 (the rhTSH group) and between January and June of 2006 (the THW group). They were assessed for serum Tg levels just before I-131 administration (TgD0), reassessed 9 days later (TgD9), and again 6-12 months later. RRA was successful in 64 (37 from the THW group and 27 from the rhTSH group) of the total 85 patients. The success rates of RRA had no statistically significant differences between the two groups. In both groups, TgD9/TgD0 values were significantly higher in the RRA success group (the rhTSH group; P=0.03, the THW group; P=0.04). By combining cutoff values of TgD0 and TgD9/TgD0, the successful RRA value was determined to be 96.7% (29/30) with TgD0≤5.28 ng/mL and TgD9/TgD0>4.37 in both groups (the rhTSH group; 100% (16/16), the THW group; 92.9% (13/14)). Using logistic multivariate analysis, only TgD0 was independently associated with successful RRA. We may predict successful ablation by evaluating short-term serum Tg elevation after I-131 administration for RRA, in both rhTSH and THW patients

  9. Oxidation behaviour of plutonium rich (U, Pu)C and (U, Pu)O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Sali, S.K., E-mail: sksali@barc.gov.in [Fuel Chemistry Division (India); Kulkarni, N.K.; Phatak, Rohan [Fuel Chemistry Division (India); Agarwal, Renu [Product Development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2016-10-15

    Oxidation behaviour of (U{sub 0.3}Pu{sub 0.7})C{sub 1.06} was investigated in air by heating samples up to 1073 K and 1273 K. Thermogravimetry (TG) of the samples and X-ray powder diffraction (XRD) of the intermediate products were used to understand the phenomenon taking place during this process. Theoretical calculations were carried out to understand the multiple phase changes taking place during oxidation of carbide. Theoretical results were validated by XRD analysis of the products obtained at different stages of oxidation. The final oxidized products were found to be a single FCC phase with O/M = 2.15 (M = U + Pu). Oxidation kinetic studies of (U{sub 0.3}Pu{sub 0.7})O{sub 2} and (U{sub 0.47}Pu{sub 0.53})O{sub 2} were carried out in dry air, using thermogravimetry, under non-isothermal conditions. The activation energy of oxidation was found to be 49 and 70 kJ/mol, respectively. Lattice parameter dependence on Pu/M and O/M of plutonium rich mixed oxide (MOX) was established using combined results of XRD and TG analysis of (U{sub 0.3}Pu{sub 0.7})O{sub 2+x} and (U{sub 0.47}Pu{sub 0.53})O{sub 2+x}.

  10. The PM2.5 capture of poly (lactic acid)/nano MOFs eletrospinning membrane with hydrophilic surface

    Science.gov (United States)

    Wang, Yating; Dai, Xiu; Li, Xu; Wang, Xinlong

    2018-03-01

    In this article, metal organic frameworks (MOFs) material is introduced in the poly (lactic acid) (PLA) by electrospinning to fabricate the nanocomposite membrane. The acrylic acid (AA) is grafted onto the membrane under UV light. The prepared membrane is studied by scanning electron microscopy (SEM), x-ray diffraction (XRD), thermogravimetry (TG), contact angle test and tensile strength test. The SEM image and XRD indicate that nano MOFs particles adhere to the membrane. Contact angle test shows that grafting AA on the composite fiber membrane improves its hydrophilicity effectively. TG analyses show that the particulate matter (PM) capture capacity of PLA membrane with 2 wt% ZIF-8 content is 22%, which rises to 37% after grafting.

  11. Synergistic effect and mechanism of platinum catalyst and nitrogen-containing silane on the thermal stability of silicone rubber

    International Nuclear Information System (INIS)

    Chen, Wanjuan; Zeng, Xingrong; Lai, Xuejun; Li, Hongqiang; Fang, Weizhen; Liu, Tian

    2016-01-01

    Highlights: • Platinum (Pt) and nitrogen-containing silane (NS) were introduced into silicone rubber. • The thermal stability was improved by Pt/NS both under nitrogen and air atmosphere. • The TG-FTIR of evolved gases during degradation was performed. • The synergistic effect and mechanism of Pt and NS were proposed. - Abstract: Platinum (Pt) catalyst and nitrogen-containing silane (NS) were introduced to improve the thermal stability of silicone rubber. The effects of Pt and NS on thermal stability and degradation mechanism of silicone rubber were investigated by thermogravimetry (TG), thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR), scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDXS) and Fourier transform infrared spectrometry (FTIR). A significant synergism was found between Pt and NS for improving the thermal stability of silicone rubber. When 6.67 ppm of Pt and 1.4 phr of NS were introduced, the temperature of 10% and 20% weight loss under nitrogen atmosphere were respectively increased by 36 °C and 119 °C. Meanwhile, the residue weight at 900 °C was doubled to 68% in the presence of Pt/NS. The synergistic mechanism might be that the nitrogen atom coordinated with Pt and improved the catalytic efficiency of Pt. Additionally, NS preserved the catalytic activity of Pt under air atmosphere. Hence, Pt/NS efficiently catalyzed thermal crosslinking and suppressed degradation of silicone chains. Moreover, it revealed that the presence of Pt/NS protected silicone chains from oxidation. Thus, the unzipping depolymerization by silanol groups was reduced significantly.

  12. Synergistic effect and mechanism of platinum catalyst and nitrogen-containing silane on the thermal stability of silicone rubber

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wanjuan; Zeng, Xingrong, E-mail: psxrzeng@gmail.com; Lai, Xuejun; Li, Hongqiang; Fang, Weizhen; Liu, Tian

    2016-05-20

    Highlights: • Platinum (Pt) and nitrogen-containing silane (NS) were introduced into silicone rubber. • The thermal stability was improved by Pt/NS both under nitrogen and air atmosphere. • The TG-FTIR of evolved gases during degradation was performed. • The synergistic effect and mechanism of Pt and NS were proposed. - Abstract: Platinum (Pt) catalyst and nitrogen-containing silane (NS) were introduced to improve the thermal stability of silicone rubber. The effects of Pt and NS on thermal stability and degradation mechanism of silicone rubber were investigated by thermogravimetry (TG), thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR), scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDXS) and Fourier transform infrared spectrometry (FTIR). A significant synergism was found between Pt and NS for improving the thermal stability of silicone rubber. When 6.67 ppm of Pt and 1.4 phr of NS were introduced, the temperature of 10% and 20% weight loss under nitrogen atmosphere were respectively increased by 36 °C and 119 °C. Meanwhile, the residue weight at 900 °C was doubled to 68% in the presence of Pt/NS. The synergistic mechanism might be that the nitrogen atom coordinated with Pt and improved the catalytic efficiency of Pt. Additionally, NS preserved the catalytic activity of Pt under air atmosphere. Hence, Pt/NS efficiently catalyzed thermal crosslinking and suppressed degradation of silicone chains. Moreover, it revealed that the presence of Pt/NS protected silicone chains from oxidation. Thus, the unzipping depolymerization by silanol groups was reduced significantly.

  13. The POZ-ZF transcription factor Kaiso (ZBTB33 induces inflammation and progenitor cell differentiation in the murine intestine.

    Directory of Open Access Journals (Sweden)

    Roopali Chaudhary

    Full Text Available Since its discovery, several studies have implicated the POZ-ZF protein Kaiso in both developmental and tumorigenic processes. However, most of the information regarding Kaiso's function to date has been gleaned from studies in Xenopus laevis embryos and mammalian cultured cells. To examine Kaiso's role in a relevant, mammalian organ-specific context, we generated and characterized a Kaiso transgenic mouse expressing a murine Kaiso transgene under the control of the intestine-specific villin promoter. Kaiso transgenic mice were viable and fertile but pathological examination of the small intestine revealed distinct morphological changes. Kaiso transgenics (Kaiso(Tg/+ exhibited a crypt expansion phenotype that was accompanied by increased differentiation of epithelial progenitor cells into secretory cell lineages; this was evidenced by increased cell populations expressing Goblet, Paneth and enteroendocrine markers. Paradoxically however, enhanced differentiation in Kaiso(Tg/+ was accompanied by reduced proliferation, a phenotype reminiscent of Notch inhibition. Indeed, expression of the Notch signalling target HES-1 was decreased in Kaiso(Tg/+ animals. Finally, our Kaiso transgenics exhibited several hallmarks of inflammation, including increased neutrophil infiltration and activation, villi fusion and crypt hyperplasia. Interestingly, the Kaiso binding partner and emerging anti-inflammatory mediator p120(ctn is recruited to the nucleus in Kaiso(Tg/+ mice intestinal cells suggesting that Kaiso may elicit inflammation by antagonizing p120(ctn function.

  14. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer’s disease (3xTgAD mice

    Directory of Open Access Journals (Sweden)

    Elysse M. Knight

    2013-01-01

    Alzheimer’s disease (AD is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD and non-transgenic (Non-Tg control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4–10 months, 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD.

  15. Age-related changes in core body temperature and activity in triple-transgenic Alzheimer’s disease (3xTgAD) mice

    Science.gov (United States)

    Knight, Elysse M.; Brown, Timothy M.; Gümüsgöz, Sarah; Smith, Jennifer C. M.; Waters, Elizabeth J.; Allan, Stuart M.; Lawrence, Catherine B.

    2013-01-01

    SUMMARY Alzheimer’s disease (AD) is characterised, not only by cognitive deficits and neuropathological changes, but also by several non-cognitive behavioural symptoms that can lead to a poorer quality of life. Circadian disturbances in core body temperature and physical activity are reported in AD patients, although the cause and consequences of these changes are unknown. We therefore characterised circadian patterns of body temperature and activity in male triple transgenic AD mice (3xTgAD) and non-transgenic (Non-Tg) control mice by remote radiotelemetry. At 4 months of age, daily temperature rhythms were phase advanced and by 6 months of age an increase in mean core body temperature and amplitude of temperature rhythms were observed in 3xTgAD mice. No differences in daily activity rhythms were seen in 4- to 9-month-old 3xTgAD mice, but by 10 months of age an increase in mean daily activity and the amplitude of activity profiles for 3xTgAD mice were detected. At all ages (4–10 months), 3xTgAD mice exhibited greater food intake compared with Non-Tg mice. The changes in temperature did not appear to be solely due to increased food intake and were not cyclooxygenase dependent because the temperature rise was not abolished by chronic ibuprofen treatment. No β-amyloid (Aβ) plaques or neurofibrillary tangles were noted in the hypothalamus of 3xTgAD mice, a key area involved in temperature regulation, although these pathological features were observed in the hippocampus and amygdala of 3xTgAD mice from 10 months of age. These data demonstrate age-dependent changes in core body temperature and activity in 3xTgAD mice that are present before significant AD-related neuropathology and are analogous to those observed in AD patients. The 3xTgAD mouse might therefore be an appropriate model for studying the underlying mechanisms involved in non-cognitive behavioural changes in AD. PMID:22864021

  16. Cyclodextrin-Complexed Ocimum basilicum Leaves Essential Oil Increases Fos Protein Expression in the Central Nervous System and Produce an Antihyperalgesic Effect in Animal Models for Fibromyalgia

    Directory of Open Access Journals (Sweden)

    Simone S. Nascimento

    2014-12-01

    Full Text Available O. basilicum leaves produce essential oils (LEO rich in monoterpenes. The short half-life and water insolubility are limitations for LEO medical uses. β-Cyclodextrin (β-CD has been employed to improve the pharmacological properties of LEO. We assessed the antihyperalgesic profile of LEO, isolated or complexed in β-CD (LEO/β-CD, on an animal model for fibromyalgia. Behavioral tests: mice were treated every day with either LEO/β-CD (25, 50 or 100 mg/kg, p.o., LEO (25 mg/kg, p.o., tramadol (TRM 4 mg/kg, i.p. or vehicle (saline, and 60 min after treatment behavioral parameters were assessed. Therefore, mice were evaluated for mechanical hyperalgesia (von Frey, motor coordination (Rota-rod and muscle strength (Grip Strength Metter in a mice fibromyalgia model. After 27 days, we evaluated the central nervous system (CNS pathways involved in the effect induced by experimental drugs through immunofluorescence protocol to Fos protein. The differential scanning analysis (DSC, thermogravimetry/derivate thermogravimetry (TG/DTG and infrared absorption spectroscopy (FTIR curves indicated that the products prepared were able to incorporate the LEO efficiently. Oral treatment with LEO or LEO-βCD, at all doses tested, produced a significant reduction of mechanical hyperalgesia and we were able to significantly increase Fos protein expression. Together, our results provide evidence that LEO, isolated or complexed with β-CD, produces analgesic effects on chronic non-inflammatory pain as fibromyalgia.

  17. Evaluation of TG-43 recommended 2D-anisotropy function for elongated brachytherapy sources

    International Nuclear Information System (INIS)

    Awan, Shahid B.; Meigooni, Ali S.; Mokhberiosgouei, Ramin; Hussain, Manzoor

    2006-01-01

    The original and updated protocols recommended by Task Group 43 from the American Association of Physicists in Medicine (i.e., TG-43 and TG-43U1, respectively), have been introduced to unify brachytherapy source dosimetry around the world. Both of these protocols are based on experiences with sources less than 1.0 cm in length. TG-43U1 recommends that for 103 Pd sources, 2D anisotropy function F(r,θ), should be tabulated at a minimum for radial distances of 0.5, 1.0, 2.0, 3.0, and 5.0 cm. Anisotropy functions defined in these protocols are only valid when the point of calculation does not fall on the active length of the source. However, for elongated brachytherapy sources (active length >1 cm), some of the calculation points with r 103 Pd source at radial distances of 2.5, 3.0, and 4.0 cm were 2.95, 1.74, and 1.19, respectively, with differences up to about a factor of 3. Therefore, the validity of the linear interpolation technique for an elongated brachytherapy source with such a large variation in F(r,θ) needs to be investigated. In this project, application of the TG-43U1 formalism for dose calculation around an elongated RadioCoil trade mark sign 103 Pd brachytherapy source has been investigated. In addition, the linear interpolation techniques as described in TG-43U1 for seed type sources have been evaluated for a 5.0 cm long RadioCoil trade mark sign 103 Pd brachytherapy source. Application of a polynomial fit to F(r,θ) has also been investigated as an alternate approach to the linear interpolation technique. The results of these investigations indicate that the TG-43U1 formalism can be extended for elongated brachytherapy sources, if the two-dimensional (2D) anisotropy function is tabulated at a minimum for radial distances of 0.2, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0 cm, L/2, and L/2±0.2 cm. Moreover, with the addition of recommended radial distances for 2D anisotropy functions, the linear interpolation technique more closely replicates

  18. MO-PIS-Exhibit Hall-01: Tools for TG-142 Linac Imaging QA I

    International Nuclear Information System (INIS)

    Clements, M; Wiesmeyer, M

    2014-01-01

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical “hands-on” information about the equipment and software systems that we use in our clinics. The therapy topic this year is solutions for TG-142 recommendations for linear accelerator imaging QA. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Automated Imaging QA for TG-142 with RIT Presentation Time: 2:45 – 3:15 PM This presentation will discuss software tools for automated imaging QA and phantom analysis for TG-142. All modalities used in radiation oncology will be discussed, including CBCT, planar kV imaging, planar MV imaging, and imaging and treatment coordinate coincidence. Vendor supplied phantoms as well as a variety of third-party phantoms will be shown, along with appropriate analyses, proper phantom setup procedures and scanning settings, and a discussion of image quality metrics. Tools for process automation will be discussed which include: RIT Cognition (machine learning for phantom image identification), RIT Cerberus (automated file system monitoring and searching), and RunQueueC (batch processing of multiple images). In addition to phantom analysis, tools for statistical tracking, trending, and reporting will be discussed. This discussion will include an introduction to statistical process control, a valuable tool in analyzing data and determining appropriate tolerances. An Introduction to TG-142 Imaging QA Using Standard Imaging Products Presentation Time: 3:15 – 3:45 PM Medical Physicists want to understand the logic behind TG-142 Imaging QA. What is often missing is a firm understanding of the connections between the EPID and OBI phantom imaging, the software “algorithms” that calculate the QA metrics, the establishment of baselines, and the analysis and interpretation of the results. The goal of our brief presentation will be to

  19. MO-PIS-Exhibit Hall-01: Tools for TG-142 Linac Imaging QA I

    Energy Technology Data Exchange (ETDEWEB)

    Clements, M [RAD Image, Colorado Springs, CO (United States); Wiesmeyer, M [Standard Imaging, Inc., Middleton, WI (United States)

    2014-06-15

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical “hands-on” information about the equipment and software systems that we use in our clinics. The therapy topic this year is solutions for TG-142 recommendations for linear accelerator imaging QA. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Automated Imaging QA for TG-142 with RIT Presentation Time: 2:45 – 3:15 PM This presentation will discuss software tools for automated imaging QA and phantom analysis for TG-142. All modalities used in radiation oncology will be discussed, including CBCT, planar kV imaging, planar MV imaging, and imaging and treatment coordinate coincidence. Vendor supplied phantoms as well as a variety of third-party phantoms will be shown, along with appropriate analyses, proper phantom setup procedures and scanning settings, and a discussion of image quality metrics. Tools for process automation will be discussed which include: RIT Cognition (machine learning for phantom image identification), RIT Cerberus (automated file system monitoring and searching), and RunQueueC (batch processing of multiple images). In addition to phantom analysis, tools for statistical tracking, trending, and reporting will be discussed. This discussion will include an introduction to statistical process control, a valuable tool in analyzing data and determining appropriate tolerances. An Introduction to TG-142 Imaging QA Using Standard Imaging Products Presentation Time: 3:15 – 3:45 PM Medical Physicists want to understand the logic behind TG-142 Imaging QA. What is often missing is a firm understanding of the connections between the EPID and OBI phantom imaging, the software “algorithms” that calculate the QA metrics, the establishment of baselines, and the analysis and interpretation of the results. The goal of our brief presentation will be to

  20. A Novel Form of Compensation in the Tg2576 Amyloid Mouse Model of Alzheimer’s Disease

    Science.gov (United States)

    Somogyi, Attila; Katonai, Zoltán; Alpár, Alán; Wolf, Ervin

    2016-01-01

    One century after its first description, pathology of Alzheimer’s disease (AD) is still poorly understood. Amyloid-related dendritic atrophy and membrane alterations of susceptible brain neurons in AD, and in animal models of AD are widely recognized. However, little effort has been made to study the potential effects of combined morphological and membrane alterations on signal transfer and synaptic integration in neurons that build up affected neural networks in AD. In this study spatial reconstructions and electrophysiological measurements of layer II/III pyramidal neurons of the somatosensory cortex from wild-type (WT) and transgenic (TG) human amyloid precursor protein (hAPP) overexpressing Tg2576 mice were used to build faithful segmental cable models of these neurons. Local synaptic activities were simulated in various points of the dendritic arbors and properties of subthreshold dendritic impulse propagation and predictors of synaptic input pattern recognition ability were quantified and compared in modeled WT and TG neurons. Despite the widespread dendritic degeneration and membrane alterations in mutant mouse neurons, surprisingly little, or no change was detected in steady-state and 50 Hz sinusoidal voltage transfers, current transfers, and local and propagation delays of PSPs traveling along dendrites of TG neurons. Synaptic input pattern recognition ability was also predicted to be unaltered in TG neurons in two different soma-dendritic membrane models investigated. Our simulations predict the way how subthreshold dendritic signaling and pattern recognition are preserved in TG neurons: amyloid-related membrane alterations compensate for the pathological effects that dendritic atrophy has on subthreshold dendritic signal transfer and integration in layer II/III somatosensory neurons of this hAPP mouse model for AD. Since neither propagation of single PSPs nor integration of multiple PSPs (pattern recognition) changes in TG neurons, we conclude that AD

  1. Characterization of sugar cane bagasse ash as raw material for the production of ceramics; Caracterizacao de cinzas de bagaco de cana como materia prima para producao de ceramica

    Energy Technology Data Exchange (ETDEWEB)

    Fredericci, C.; Indelicato, R.L.; Ferreira Neto, J.B.; Ribeiro, T.R.; Landgraf, F.J.G., E-mail: catiaf@ipt.br [Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo (IPT), Sao Paulo, SP (Brazil). Lab. de Metalurgia e Materiais Ceramicos; Silva, G.F.B. Lenz e [Universidade de Sao Paulo (Poli/USP), Sao Paulo, SP (Brazil). Escola Politecnica. Departamento de Engenharia Metalurgica e de Materiais

    2012-07-01

    The aim of this paper was to analyze the sugar cane bagasse ash from three Sugar and Alcohol Plant of the State of Sao Paulo - Brazil. We intend to show the discrepancies between them, so that this raw material could be used with greater quality control in ceramic industries. The bagasse were analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and scanning electron microscopy. The ashes were analyzed by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, energy dispersive spectroscopy, and granulometric separation. The results indicated that the content of SiO{sub 2} ranging from 50-80% by weight depends on the granulometry of the bagasse and on the region where it was collected. The analyses of X-ray diffraction indicate SiO{sub 2}, Fe{sub 2}O{sub 3}, K{sub 2}SO{sub 4} and Mg{sub 2}P{sub 2}O{sub 7} as crystalline phases. (author)

  2. Experimental analysis on physical and mechanical properties of thermal shock damage of granite

    Directory of Open Access Journals (Sweden)

    He Xiao

    2017-01-01

    Full Text Available The purpose of this study was to explore the changes of mechanical and physical properties of granite under different thermal loading effects. Uniaxial compression experiments studying the rules of the influence of temperature load on mechanical properties of granite were carried out. After high-temperature heating at above 600 °C, granite tended to have stronger ductility and plasticity as well as declined peak stress and compressive strength. Thermogravimetry - differential scanning calorimetry (TG-DSC analysis results showed that, thermal load at different temperatures induced reactions such as water loss, oxidation and crystallization in the microstructure of granite, which led to physical changes of granite. Hence it is concluded that, heating can significantly weaken the mechanical performance of granite, which provides an important support for the optimization of heating assisted processing of granite. It also reveals that, heating assisted cutting technique can effectively lower energy consumption and improve processing efficiency.

  3. Preparation of CL-20 Explosive Nanoparticles and Their Thermal Decomposition Property

    Directory of Open Access Journals (Sweden)

    Dunju Wang

    2016-01-01

    Full Text Available Herein, we develop a novel method for preparing nanohexanitrohexaazaisowurtzitane (nano-CL-20 via ultrasonic spray-assisted electrostatic adsorption (USEA technology. Various experimental conditions which influence safety factors and the crystallization process were studied. Meanwhile, the prepared nano-CL-20 particles were characterized by field emission scanning electron microscopy (FE-SEM, X-ray diffraction (XRD, and Fourier transform infrared (FT-IR spectroscopy. The results show that the obtained nano-CL-20 showed a wide size distribution in the range from 150 to 600 nm with an average of 270 nm. Moreover, their thermal properties were also investigated by differential scanning calorimetry (DSC and thermogravimetry (TG. For nano-CL-20, the exothermal peak is 232.9°C increased by 12°C compared with conventionally manufactured (CM CL-20, and they exhibit fast energy release efficiency as well as more energy release. The simple and continuous approach presented here is expected to be an attractive potential for fabricating other organic nanoparticles.

  4. Characterization of Al{sub 2}O{sub 3}-Co ceramic composite obtained by high energy mill; Caracterizacao de composito ceramico Al{sub 2}O{sub 3}-CO obtido por moagem de alta energia (MAE)

    Energy Technology Data Exchange (ETDEWEB)

    Souza, J.L.; Assis, R.B. de; Carlos, E.M.; Oliveira, T.P.; Costa, F.A. da, E-mail: leonaldojs@hotmail.com [Universidade Federal do Rio Grande do Norte (PPGCEM/UFRN), Natal, RN (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica

    2014-07-01

    This work aims to characterize the ceramic composite Al{sub 2}O3-Co obtained by high energy grinding. The composites were obtained by milling Al{sub 2}O{sub 3} and Co in a high energy mill at a speed of 400 rpm, in proportions of 5 to 20% Cobalt (Co). Ceramic composites with 5 and 20% cobalt were sintered at 1200 and 1300 ° C, with a 60-minute plateau and a heating rate of 10 ° C / min. The samples were characterized by X-ray diffraction (XRD), thermogravimetry and differential scanning calorimetry (TG / DSC) and scanning electron microscopy (SEM). The results show the significant effect of cobalt percentage and high energy grinding on the final properties of the Al{sub 2}O{sub 3} - Co ceramic composite, presenting satisfactory values for the composite with a 20% cobalt percentage, showing to be a promising material for application in cutting tools.

  5. Terahertz spectroscopic investigation of gallic acid and its monohydrate

    Science.gov (United States)

    Zhang, Bo; Li, Shaoping; Wang, Chenyang; Zou, Tao; Pan, Tingting; Zhang, Jianbing; Xu, Zhou; Ren, Guanhua; Zhao, Hongwei

    2018-02-01

    The low-frequency spectra of gallic acid (GA) and its monohydrate were investigated by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.5 to 4.5 THz. The dehydration process of GA monohydrate was monitored on-line. The kinetic mechanism of the dehydration process was analyzed depending on the THz spectral change at different temperatures. The results indicate that the diffusion of water molecule dominates the speed of the entire dehydration process. Solid-state density functional theory (DFT) calculations of the vibrational modes of both GA and its monohydrate were performed based on their crystalline structures for better interpreting the experimental THz spectra. The results demonstrate that the characterized features of GA mainly originate from the collective vibrations of molecules. And the interactions between GA and water molecules are responsible for THz fingerprint of GA monohydrate. Multi-techniques including differential scanning calorimetry and thermogravimetry (DSC-TG) and powder X-ray diffraction (PXRD) were also carried out to further investigate GA and its monohydrate.

  6. Synthesis and properties of large crystal of aluminum-deficient ultrasil molecular sieve materials

    International Nuclear Information System (INIS)

    Durrani, J.; Akhtar, J.; Chughtai, N.A.; Arif, M.; Saeed, K.; Ahmed, M.; Siddique, M.

    2003-01-01

    Large crystals of aluminum-deficient and silica rich molecular sieve materials such as Silicalite-I, Silicalite-II ZSM11-B and ZSM11-Fe have been synthesized hydro thermally from the aqueous silicate gel of (R/sub 2/O -SiO/sub 2/- B/sub 2/O/sub 3/ -Fe/sub 2/O/ sub 3/ -H/sub 2/O) using PTFE-lined stainless digestion bomb. The term R is a alkyl group. The synthesized materials were identified for crystallinity, thermal stability, phase, crystal structure, morphology and unit cell dimensions using thermogravimetry (TG/DTA), differential scanning calorimetric(DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and other analytical techniques. All product materials were found to be white crystalline and crysto-graphically pure. Surface area and particle size distribution of materials were also ascertained. /sup 57/Fe Mossbauer spectroscopic studies on as-synthesized and calcined samples have confirmed the uniform dispersion of Fe/sup 3+/ ions in the tetrahedral framework of ZSM11-Fe material. (author)

  7. Synthesis and characterization of NiO-YSZ-CeO_2 composites with microwave-assisted hydrothermal treatment

    International Nuclear Information System (INIS)

    Pinheiro, Lucas Batochi

    2013-01-01

    In the present work, it was evaluated the effects of a microwave-assisted hydrothermal (MWH) treatment on structural, thermal and electrical properties of NiO-YSZ- CeO_2 composites synthesized by hydroxide coprecipitation method. Simultaneous thermogravimetry and differential thermal analysis (TG/DTA) in conjunction with x-ray diffraction (XRD) measurements showed that MWH treatment contributed to enhanced nickel hydroxide crystallization. The linear shrinkage of the ceramic compacts was observed by thermomechanical analysis (TMA) and the results indicated a higher sinterability for the samples MWH-treated. The compacts were sintered in a conventional resistive and in a microwave furnace. This sintered compacts had their microstructure analyzed by scanning electron microscopy (SEM) and electrical properties investigated by impedance spectroscopy (IS). The SEM images showed phase homogeneity and sub-micrometric grains with irregular shapes. The IS data revealed that the MWH-treated samples have a conductivity increase for temperatures above 500 deg C regardless the sintering process. (author)

  8. Influence of expandable graphite on fire resistance and water resistance of flame-retardant coatings

    International Nuclear Information System (INIS)

    Wang, Zhenyu; Han, Enhou; Ke, Wei

    2007-01-01

    Expandable graphite (EG) coating and ammonium polyphosphate-pentaerythritol-melamine (APP-PER-MEL) coating were prepared. Thermal degradation and char formation of the coatings were investigated by differential thermal analysis (DTA), thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results have shown that the anti-oxidation and fire-resistant properties of expandable graphite coating containing EG with size of 74 μm are better than those of APP-PER-MEL coating. The static immersion test was applied to study water resistance of the coatings, and the fire protection test and mechanical test were used to analyse heat insulation and mechanical properties of coatings before and after water immersion. The fire-resistant and mechanical properties of APP-PER-MEL coating were severely damaged by water immersion, whereas EG coating containing 8.5% EG with size of 74 μm could retain the good fire resistance even after 500 h water immersion

  9. The effects of Mg incorporation and annealing temperature on the physicochemical properties and antibacterial activity against Listeria monocytogenes of ZnO nanoparticles

    Science.gov (United States)

    Shadan, Nima; Ziabari, Ali Abdolahzadeh; Meraat, Rafieh; Jalali, Kamyar Mazloum

    2017-02-01

    In this paper, Mg-doped ZnO nanoparticles were synthesized by the facile sol-gel method. The crystalline structure, characteristic absorption bands and morphology of the obtained Mg-doped ZnO nanoparticles were studied by XRD, FTIR and TEM. The thermal degradation behaviour of the samples was investigated by differential scanning calorimetry (DSC) and thermogravimetry (TG). The effect of Mg concentrations and annealing temperatures on the antibacterial properties of the obtained nanoparticles was investigated in detail. The results indicated that doping Mg ions into ZnO lattice could enhance its antibacterial activity. Antibacterial assay demonstrated that Mg-doped ZnO with 7% Mg content annealed at 400 ∘C had the strongest antibacterial activity against Listeria monocytogenes (98.7%). This study indicated that the inhibition rate of ZnO nanoparticles increased with the formation of granular structure and the decrease of ZnO size due to the doping of Mg ions into the ZnO lattice.

  10. New double-cation borohydrides

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, Inge; Domenech Ferrer, Roger; Schultz, Ludwig; Gutfleisch, Oliver [IFW Dresden, Institute for Metallic Materials, P.O. Box 270016, 01171 Dresden (Germany); Filinchuk, Yaroslav [Swiss-Norwegian Beam Lines at ESRF, BP-220, 38043 Grenoble (France); Hagemann, Hans; Cerny, Radovan [Department of Physical Chemistry and Crystallography, University of Geneva, 1211 Geneva (Switzerland)

    2011-07-01

    Complex hydrides are under consideration for on-board hydrogen storage due to their high hydrogen density. However, up to now conventional borohydrides are either too stable or unstable for applications as in PEM fuel cells (60-120 C). Recently, double-cation borohydride systems have attracted great interest. The desorption temperature of the borohydrides decreases with increasing electronegativity of the cation. Consequently, it is possible to tailor a feasible on-board hydrogen storage material by the combination of appropriate cations. The stability was found to be intermediate between the single-cation borohydride systems. Two combinations were sucessfully synthesised by metathesis reaction via high energy ball milling. Al-Li-borohydride shows desorption at about 70 C combined with a very high hydrogen density (17.2 wt.%) and the Na-Al-borohydride (14.2 wt.%) decomposes around 90 C. Both desorption temperatures are in the target range for applications. The decomposition pathways were observed by in-situ-Raman spectroscopy, DSC (Differential Scanning Calorimetry), TG (Thermogravimetry) and thermal desorption measurements.

  11. Incorporation of zinc into calcium silicate hydrates, Part I: formation of C-S-H(I) with C/S=2/3 and its isochemical counterpart gyrolite

    International Nuclear Information System (INIS)

    Stumm, Andreas; Garbev, Krassimir; Beuchle, Guenter; Black, Leon; Stemmermann, Peter; Nueesch, Rolf

    2005-01-01

    We have investigated the incorporation of zinc into both nanocrystalline and crystalline calcium silicate hydrates with starting C/S ratios of 2/3 (0.66). Zinc was added replacing calcium in the starting mixtures [Zn/(Zn+Ca)=0-1/4; 0-10 wt.% Zn], and the resultant phases were characterised using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), differential thermal analysis-thermogravimetry (DTA-TG) and environmental scanning electron microscopy (ESEM). In both groups of samples, increasing zinc content led to gradual structural changes, until eventually a second phase was formed. Zinc was incorporated to similar limits in both sets of samples. The thermal stability of the structures increased to a certain zinc content, beyond which there was structural destabilisation. Zinc incorporation is possible up to ∼6 wt.%. Our observations strongly indicate similar zinc incorporation mechanisms in both sample series, namely incorporation of zinc into the interlayer of C-S-H(I) and the X-sheet of gyrolite for nanocrystalline and crystalline samples, respectively

  12. Knudsen thermogravimetry approach to the thermodynamics of aqueous solutions

    International Nuclear Information System (INIS)

    Schiraldi, Alberto; Signorelli, Marco; Fessas, Dimitrios

    2013-01-01

    Highlights: ► Knudsen cells were designed to replace standard TG pans for desorption experiments. ► The Knudsen effusion data allow determination of water activity of aqueous solutions. ► This methods can replace the traditional isopiestic approach for aqueous solutions. ► The Gibbs–Duhem relationship was used to fit the experimental data. -- Abstract: The use of isothermal TGA with Knudsen-like cells allows determination of the thermodynamic activity of water, a W . The typical experiment implies a slow dehydration of the aqueous solution at constant temperature in dynamic vacuum conditions. The method is alternative to the classical isopiestic approach and offers the advantage of a continuous record on increasing the solute concentration. These data can be directly treated according to the classical thermodynamic relationships drawn from the Gibbs–Duhem expression to evaluate the activity and osmotic coefficient of the aqueous solutions of electrolytes and non-electrolytes, and, in the case of electrolytes, allow determination of solubility of the solute. Discrepancies with respect to the literature data are observed when the viscosity of the systems becomes too high, as in the case of sugars with a very large solubility. Such a mismatch may however be accounted for either slowing the dehydration rate with use of a narrower Knudsen orifice, or correcting the experimental a W with a calibration curve. The same approach can be applied to non-aqueous solutions

  13. Download - Open TG-GATEs | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...Download License Update History of This Database Site Policy | Contact Us Download - Open TG-GATEs | LSDB Archive ...

  14. TH-A-BRC-02: AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance

    Energy Technology Data Exchange (ETDEWEB)

    Goetsch, S. [San Diego Medical Physics (United States)

    2016-06-15

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  15. TH-A-BRC-02: AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance

    International Nuclear Information System (INIS)

    Goetsch, S.

    2016-01-01

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  16. Effect of mechanical activation on structure and thermal decomposition of aluminum sulfate

    International Nuclear Information System (INIS)

    Ghasri-Khouzani, M.; Meratian, M.; Panjepour, M.

    2009-01-01

    The thermal decompositions of both non-activated and mechanically activated aluminum sulfates were studied by thermogravimetry (TG). The structural disorder, the specific surface area (SSA) and the morphology of mechanically activated aluminum sulfates were analyzed by X-ray diffraction (XRD), laser particle-size analyzer, and scanning electron microscopy (SEM), respectively. Thermal analyses results indicated that the initial temperature of thermal decomposition (T i ) in TG curves for mechanically activated aluminum sulfates decreased gradually with increasing the milling time. It was also found that the SSA of mechanically activated aluminum sulfates remained almost constant after a certain milling time, and lattice strains (ε) rose but the crystallite sizes (D) decreased with increasing the milling time. These results showed that the decrease of T i in TG curves of mechanically activated aluminum sulfates was mainly caused by the increase of lattice distortions and decrease of the crystallite sizes with increasing the milling time

  17. Development of nanocomposites polyamide66/ bentonite clay membranes obtained by solution for water-oil separation

    International Nuclear Information System (INIS)

    Medeiros, Keila Machado de

    2010-01-01

    Microporous membranes were obtained from nanocomposites polyamide66 and regional bentonite clay, through the technique of immersion precipitation. The nanocomposites were obtained by solution with a pre-established reaction time. The clay was treated with quaternary ammonium salt (Cetremide®) in order to make it organophilic. Untreated and treated clay were characterized by X-ray fluorescence (XRF) spectroscopy, Fourier transform infrared (FTIR), X-ray diffraction (XRD) and thermogravimetry (TG), which confirmed the insertion of the Cetremide® salt in the layers of clay and their thermal stability. While the membranes were characterized by XRD, TG, differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and flow measurements. The results of XRD, TG and DSC confirmed the thermal stability and morphological structure with intercalated/partially exfoliated lamellae of clay in the polymer matrix. By SEM, it was revealed an asymmetric morphology consisting of a skin layer and a porous sublayer. The higher clay content in the membrane give the lower film thickness. This influencing directly the flow measurements of the membranes produced from the nanocomposites. In general, the initial flow with distilled water through the membranes decrease and stabilise after 60 min, this due to a compression or swelling occurred in the membranes. In tests of water-oil separation it was found that the relationship J/J0 tends to be greater when using emulsions with lower concentration. The water-oil separation tests at concentrations of 300 and 500 ppm for all membranes showed a significant reduction in oil concentration in the permeate, thus showing that these membranes have potential for this application. (author)

  18. Thermal analysis of wood of the main tree species of Central Siberia

    Directory of Open Access Journals (Sweden)

    S. R. Loskutov

    2015-12-01

    Full Text Available Thermal decomposition of wood from coniferous and deciduous species of Siberia has been studied using thermogravimetry (TG and differential scanning calorimetry (DSC. The tree species were larch Larix sibirica Ledeb., Scots pine Pinus sylvestris L., spruce Picea obovata Ledeb., fir Abies sibirica Ledeb., Siberian pine Pinus sibirica Du Tour., birch Betula pendula Roth., and aspen Populus tremula L. Thermal analysis of wood samples was carried out under oxidative (air and inert (argon atmospheres from 25 to 700 °С at heating rates 10, 20, 40 °С • min–1 (TG/DTG and from 25 to 590 °С at heating rates 10, 40 °С • min–1 (DSC. The stages of thermal decomposition, the temperature intervals, the mass loss, the mass loss rate, the temperature of DTG/DSC peaks, and heating effects were determined for each tree species. The kinetic thermal degradation parameters of wood were obtained by the Broido and Ozawa–Flynn–Wall models. The wood of coniferous and deciduous species of Siberia was characterized on the base of analysis of activation energy values at various stages of thermal decomposition and the relations of activation energy on conversion level of wood substance of different tree species, and also the comparison of mass loss at the same stages of thermal destruction, heating effects, residual mass and other parameters of TG/DTG, DSC. In our opinion, the results of this work present interest for researchers and specialists in the field of forest pyrology, wood science, dendrochemistry.

  19. Bone-derived mesenchymal stromal cells from HIV transgenic mice exhibit altered proliferation, differentiation capacity and paracrine functions along with impaired therapeutic potential in kidney injury

    International Nuclear Information System (INIS)

    Cheng, Kang; Rai, Partab; Lan, Xiqian; Plagov, Andrei; Malhotra, Ashwani; Gupta, Sanjeev; Singhal, Pravin C.

    2013-01-01

    Mesenchymal stem cells (MSCs) secrete paracrine factors that could be cytoprotective and serve roles in immunoregulation during tissue injury. Although MSCs express HIV receptors, and co-receptors, and are susceptible to HIV infection, whether HIV-1 may affect biological properties of MSCs needs more study. We evaluated cellular proliferation, differentiation and paracrine functions of MSCs isolated from compact bones of healthy control mice and Tg26 HIV-1 transgenic mice. The ability of MSCs to protect against cisplatin toxicity was studied in cultured renal tubular cells as well as in intact mice. We successfully isolated MSCs from healthy mice and Tg26 HIV-1 transgenic mice and found the latter expressed viral Nef, Vpu, NL4-3 and Vif genes. The proliferation and differentiation of Tg26 HIV-1 MSCs was inferior to MSCs from healthy mice. Moreover, transplantation of Tg26 HIV-1 MSCs less effectively improved outcomes compared with healthy MSCs in mice with acute kidney injury. Also, Tg26 HIV-1 MSCs secreted multiple cytokines, but at significantly lower levels than healthy MSCs, which resulted in failure of conditioned medium from these MSCs to protect cultured renal tubular cells from cisplatin toxicity. Therefore, HIV-1 had adverse biological effects on MSCs extending to their proliferation, differentiation, function, and therapeutic potential. These findings will help in advancing mechanistical insight in renal injury and repair in the setting of HIV-1 infection. -- Highlights: •MSCs isolated from HIV mice displayed HIV genes. •MSCs isolated from HIV mice exhibited attenuated growth and paracrine functions. •AKI mice with transplanted HIV-MSC displayed poor outcome. •HIV-1 MSC secreted multiple cytokines but at a lower level

  20. Bone-derived mesenchymal stromal cells from HIV transgenic mice exhibit altered proliferation, differentiation capacity and paracrine functions along with impaired therapeutic potential in kidney injury

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Kang; Rai, Partab; Lan, Xiqian; Plagov, Andrei; Malhotra, Ashwani [Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhassett, NY (United States); Gupta, Sanjeev [Departments of Medicine and Pathology, Marion Bessin Liver Research Center, Diabetes Center, Cancer Center, Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research, Institute for Clinical and Translational Research, Albert Einstein College of Medicine, Bronx, NY (United States); Singhal, Pravin C., E-mail: psinghal@nshs.edu [Feinstein Institute for Medical Research, North Shore-Long Island Jewish Health System, Manhassett, NY (United States)

    2013-08-15

    Mesenchymal stem cells (MSCs) secrete paracrine factors that could be cytoprotective and serve roles in immunoregulation during tissue injury. Although MSCs express HIV receptors, and co-receptors, and are susceptible to HIV infection, whether HIV-1 may affect biological properties of MSCs needs more study. We evaluated cellular proliferation, differentiation and paracrine functions of MSCs isolated from compact bones of healthy control mice and Tg26 HIV-1 transgenic mice. The ability of MSCs to protect against cisplatin toxicity was studied in cultured renal tubular cells as well as in intact mice. We successfully isolated MSCs from healthy mice and Tg26 HIV-1 transgenic mice and found the latter expressed viral Nef, Vpu, NL4-3 and Vif genes. The proliferation and differentiation of Tg26 HIV-1 MSCs was inferior to MSCs from healthy mice. Moreover, transplantation of Tg26 HIV-1 MSCs less effectively improved outcomes compared with healthy MSCs in mice with acute kidney injury. Also, Tg26 HIV-1 MSCs secreted multiple cytokines, but at significantly lower levels than healthy MSCs, which resulted in failure of conditioned medium from these MSCs to protect cultured renal tubular cells from cisplatin toxicity. Therefore, HIV-1 had adverse biological effects on MSCs extending to their proliferation, differentiation, function, and therapeutic potential. These findings will help in advancing mechanistical insight in renal injury and repair in the setting of HIV-1 infection. -- Highlights: •MSCs isolated from HIV mice displayed HIV genes. •MSCs isolated from HIV mice exhibited attenuated growth and paracrine functions. •AKI mice with transplanted HIV-MSC displayed poor outcome. •HIV-1 MSC secreted multiple cytokines but at a lower level.

  1. Influence of the thyroid remnant in the elevation of the serum thyroglobulin after thyroidectomy in differentiated thyroid carcinoma. Importance of the diagnostic iodine total-body scanning

    International Nuclear Information System (INIS)

    Caballero-Calabuig, Elisa; Cano-Terol, Carmen; Sopena-Monforte, Ramon; Reyes-Ojeda, Dolores; Abreu-Sanchez, Pedro; Ferrer-Rebolleda, Jose; Sopena-Novales, Pablo; Plancha-Mansanet, Carmen; Felix-Fontestad, Jesus

    2008-01-01

    Stimulated thyroglobulin (Tg) and 131 I total-body scan (TBS) have been the mainstays of differentiated thyroid carcinoma (DTC), but now diagnostic TBS has been eliminated from some follow-up protocols. Nevertheless, Tg can be negative in the presence of thyroid tissue, and moderately elevated Tg poses management problems. The purpose of this study was to check how many patients have Tg negative but visible thyroid tissue and if diagnostic TBS could be clinically useful. Retrospective review of 317 exams (stimulated Tg and TBS) of 128 patients with DTC. Patients with high-grade criteria and/or positive autoantibodies are excluded. Tg is considered positive if higher than the sensitivity level of the technique. TBS is positive if thyroid remnant, lymphatic node or metastases are detected. Results are classified in Tg and TBS concordant or discordant. Discordant 131 I TBS and Tg were found in 74/317 studies (23.3%), 48 (65%) being TBS positive and Tg negative. None of 128 patients had a first post-surgery negative scan, but 13 (10%) were Tg negative, even two patients with lymph node uptake. One year after radioiodine treatment, 26 out of 115 patients (initially Tg and TBS concordant positive) showed Tg negative and TBS still positive due to cervical remnants (20 patients), lymph node uptake (one) and metastasis (five); 20 patients remained Tg and TBS positive, but 14 of them only showed thyroid remnants. We propose to perform periodic diagnostic TBS to improve Tg specificity, at least while neck thyroid activity is detected, even if Tg is negative. (orig.)

  2. Influence of the thyroid remnant in the elevation of the serum thyroglobulin after thyroidectomy in differentiated thyroid carcinoma. Importance of the diagnostic iodine total-body scanning

    Energy Technology Data Exchange (ETDEWEB)

    Caballero-Calabuig, Elisa; Cano-Terol, Carmen; Sopena-Monforte, Ramon; Reyes-Ojeda, Dolores; Abreu-Sanchez, Pedro; Ferrer-Rebolleda, Jose; Sopena-Novales, Pablo; Plancha-Mansanet, Carmen; Felix-Fontestad, Jesus [Hospital Universitario Dr. Peset - Medicina Nuclear, Valencia, Valencia (Spain)

    2008-08-15

    Stimulated thyroglobulin (Tg) and {sup 131}I total-body scan (TBS) have been the mainstays of differentiated thyroid carcinoma (DTC), but now diagnostic TBS has been eliminated from some follow-up protocols. Nevertheless, Tg can be negative in the presence of thyroid tissue, and moderately elevated Tg poses management problems. The purpose of this study was to check how many patients have Tg negative but visible thyroid tissue and if diagnostic TBS could be clinically useful. Retrospective review of 317 exams (stimulated Tg and TBS) of 128 patients with DTC. Patients with high-grade criteria and/or positive autoantibodies are excluded. Tg is considered positive if higher than the sensitivity level of the technique. TBS is positive if thyroid remnant, lymphatic node or metastases are detected. Results are classified in Tg and TBS concordant or discordant. Discordant {sup 131}I TBS and Tg were found in 74/317 studies (23.3%), 48 (65%) being TBS positive and Tg negative. None of 128 patients had a first post-surgery negative scan, but 13 (10%) were Tg negative, even two patients with lymph node uptake. One year after radioiodine treatment, 26 out of 115 patients (initially Tg and TBS concordant positive) showed Tg negative and TBS still positive due to cervical remnants (20 patients), lymph node uptake (one) and metastasis (five); 20 patients remained Tg and TBS positive, but 14 of them only showed thyroid remnants. We propose to perform periodic diagnostic TBS to improve Tg specificity, at least while neck thyroid activity is detected, even if Tg is negative. (orig.)

  3. Comparative biodegradation of HDPE and LDPE using an indigenously developed microbial consortium.

    Science.gov (United States)

    Satlewal, Alok; Soni, Ravindra; Zaidi, Mgh; Shouche, Yogesh; Goel, Reeta

    2008-03-01

    A variety of bacterial strains were isolated from waste disposal sites of Uttaranchal, India, and some from artificially developed soil beds containing maleic anhydride, glucose, and small pieces of polyethylene. Primary screening of isolates was done based on their ability to utilize high- and low-density polyethylenes (HDPE/LDPE) as a primary carbon source. Thereafter, a consortium was developed using potential strains. Furthermore, a biodegradation assay was carried out in 500-ml flasks containing minimal broth (250 ml) and HDPE/ LDPE at 5 mg/ml concentration. After incubation for two weeks, degraded samples were recovered through filtration and subsequent evaporation. Fourier transform infrared spectroscopy (FTIR) and simultaneous thermogravimetric-differential thermogravimetry-differential thermal analysis TG-DTG-DTA) were used to analyze these samples. Results showed that consortium-treated HDPE (considered to be more inert relative to LDPE) was degraded to a greater extent 22.41% weight loss) in comparison with LDPE (21.70% weight loss), whereas, in the case of untreated samples, weight loss was more for LDPE than HDPE (4.5% and 2.5%, respectively) at 400 degrees . Therefore, this study suggests that polyethylene could be degraded by utilizing microbial consortia in an eco-friendly manner.

  4. Study of vaporization of sodium metaborate by transpiration thermogravimetry and Knudsen effusion mass spectrometry.

    Science.gov (United States)

    Narasimhan, T S Lakshmi; Viswanathan, R; Nalini, S

    2011-11-17

    The vaporization of solid sodium metaborate NaBO(2)(s) was studied by transpiration thermogravimetry (TTG) and Knudsen effusion mass spectrometry (KEMS). The transpiration measurements, performed for the first time on NaBO(2)(s), involved use of argon as the carrier gas for vapor transport and derivation of vapor pressure of NaBO(2)(g) (by assuming it as the sole vapor species) through many flow-dependence runs and temperature-dependence runs in the temperature range 1075-1218 K. The KEMS measurements performed in the temperature range 1060-1185 K confirmed NaBO(2)(g) as the principal vapor species over NaBO(2)(s), in accord with the previously reported KEMS studies. The values of p(NaBO(2)) obtained by both TTG and KEMS are consistent within the uncertainties associated with each method and so are the second- and third-law values of enthalpy of sublimation, the latter aspect consistently missing in all previous vaporization studies. The results of both TTG and KEMS were combined to recommend the following thermodynamic parameters pertinent to the sublimation reaction, NaBO(2)(s) = NaBO(2)(g): Log{p(NaBO(2))/Pa} = -(17056 ± 441)/(T/K) + (14.73 ± 0.35) for the temperature range 1060-1218 K; Δ(r)H°(m)(298.15 K) = (346.3 ± 9.4) kJ·mol(-1); and Δ(r)S°(m)(298.15 K) = (210.2 ± 6.8) J·mol(-1)·K(-1).

  5. Report of AAPM TG 135: quality assurance for robotic radiosurgery.

    Science.gov (United States)

    Dieterich, Sonja; Cavedon, Carlo; Chuang, Cynthia F; Cohen, Alan B; Garrett, Jeffrey A; Lee, Charles L; Lowenstein, Jessica R; d'Souza, Maximian F; Taylor, David D; Wu, Xiaodong; Yu, Cheng

    2011-06-01

    The task group (TG) for quality assurance for robotic radiosurgery was formed by the American Association of Physicists in Medicine's Science Council under the direction of the Radiation Therapy Committee and the Quality Assurance (QA) Subcommittee. The task group (TG-135) had three main charges: (1) To make recommendations on a code of practice for Robotic Radiosurgery QA; (2) To make recommendations on quality assurance and dosimetric verification techniques, especially in regard to real-time respiratory motion tracking software; (3) To make recommendations on issues which require further research and development. This report provides a general functional overview of the only clinically implemented robotic radiosurgery device, the CyberKnife. This report includes sections on device components and their individual component QA recommendations, followed by a section on the QA requirements for integrated systems. Examples of checklists for daily, monthly, annual, and upgrade QA are given as guidance for medical physicists. Areas in which QA procedures are still under development are discussed.

  6. Microglial response to Alzheimer's disease is differentially modulated by voluntary wheel running and enriched environments.

    Science.gov (United States)

    Rodríguez, J J; Noristani, H N; Verkhratsky, A

    2015-03-01

    Alzheimer's disease (AD) is an untreatable neurodegenerative disease that deteriorates memory. Increased physical/cognitive activity reduces dementia risk by promoting neuronal and glial response. Although few studies have investigated microglial response in wild-type rodents following exposure to physical/cognitive stimulation, environmental-induced changes of microglia response to AD have been neglected. We investigated effects of running (RUN) and enriched (ENR) environments on numerical density (N v, #/mm(3)) and morphology of microglia in a triple transgenic (3×Tg-AD) mouse model of AD that closely mimics AD pathology in humans. We used immunohistochemical approach to characterise microglial domain by measuring their overall cell surface, volume and somata volume. 3×Tg-AD mice housed in standard control (STD) environment showed significant increase in microglial N v (11.7 %) in CA1 stratum lacunosum moleculare (S.Mol) of the hippocampus at 12 months compared to non-transgenic (non-Tg) animals. Exposure to combined RUN and ENR environments prevented an increase in microglial N v in 3×Tg-AD and reduced microglial numbers to non-Tg control levels. Interestingly, 3×Tg-AD mice housed solely in ENR environment displayed significant decrease in microglial N v in CA1 subfield (9.3 % decrease), stratum oriens (11.5 % decrease) and S.Mol (7.6 % decrease) of the hippocampus compared to 3×Tg-AD mice housed in STD environment. Morphological analysis revealed microglial hypertrophy due to pronounced increase in microglia surface, volume and somata volume (61, 78 and 41 %) in 3×Tg-AD mice housed in RUN (but not in ENR) compared to STD environment. These results indicate that exposure to RUN and ENR environments have differential effects on microglial density and activation-associated changes in microglial morphology.

  7. A novel Toxoplasma gondii nuclear factor TgNF3 is a dynamic chromatin-associated component, modulator of nucleolar architecture and parasite virulence.

    Directory of Open Access Journals (Sweden)

    Alejandro Olguin-Lamas

    2011-03-01

    Full Text Available In Toxoplasma gondii, cis-acting elements present in promoter sequences of genes that are stage-specifically regulated have been described. However, the nuclear factors that bind to these cis-acting elements and regulate promoter activities have not been identified. In the present study, we performed affinity purification, followed by proteomic analysis, to identify nuclear factors that bind to a stage-specific promoter in T. gondii. This led to the identification of several nuclear factors in T. gondii including a novel factor, designated herein as TgNF3. The N-terminal domain of TgNF3 shares similarities with the N-terminus of yeast nuclear FK506-binding protein (FKBP, known as a histone chaperone regulating gene silencing. Using anti-TgNF3 antibodies, HA-FLAG and YFP-tagged TgNF3, we show that TgNF3 is predominantly a parasite nucleolar, chromatin-associated protein that binds specifically to T. gondii gene promoters in vivo. Genome-wide analysis using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq identified promoter occupancies by TgNF3. In addition, TgNF3 has a direct role in transcriptional control of genes involved in parasite metabolism, transcription and translation. The ectopic expression of TgNF3 in the tachyzoites revealed dynamic changes in the size of the nucleolus, leading to a severe attenuation of virulence in vivo. We demonstrate that TgNF3 physically interacts with H3, H4 and H2A/H2B assembled into bona fide core and nucleosome-associated histones. Furthermore, TgNF3 interacts specifically to histones in the context of stage-specific gene silencing of a promoter that lacks active epigenetic acetylated histone marks. In contrast to virulent tachyzoites, which express the majority of TgNF3 in the nucleolus, the protein is exclusively located in the cytoplasm of the avirulent bradyzoites. We propose a model where TgNF3 acts essentially to coordinate nucleolus and nuclear functions by modulating

  8. Local lymph node assay: how testing laboratories apply OECD TG 429 for REACH purposes.

    Science.gov (United States)

    Rovida, Costanza

    2011-01-01

    The Local Lymph Node Assay (LLNA) is the official method for assessing the allergic contact dermatitis potential of chemicals for the purposes of REACH regulation. The LLNA went through a validation process that allowed the delineation of a robust protocol for performing new tests. The OECD accepted this method in 2002 and published OECD TG 429. The European Chemical Agency (ECHA) recently published data that were submitted in the registration dossiers of chemicals. This database was analysed to determine how testing laboratories apply OECD TG 429. This analysis comes after a detailed analysis of four full study reports that were also prepared for REACH purposes. Although the majority of the tests are fully compliant with OECD TG 429, some showed major deviations, and a number of others used more animals than necessary. This suggests that in vivo tests need to be planned more carefully and consciously to obtain meaningful results with the minimum animal number necessary.

  9. MODEL OF A PROCESS FOR DRYING Eucalyptus spp AT HIGH TEMPERATURES

    Directory of Open Access Journals (Sweden)

    P. C. C. PINHEIRO

    1998-12-01

    Full Text Available A mathematical model of a process for drying of Eucalyptus spp is presented. This model was based on fundamental heat and mass transfer equations and it was numerically solved using a segregated finite volume method. Software in the FORTRAN language was developed to solve the mathematical model. The kinetic parameters of drying for Eucalyptus spp were experimentally obtained by isothermal thermogravimetry (TG. The theoretical results generated using the mathematical model were validated by experimental data.

  10. Obtaining nanofibers from sisal to reinforce nanocomposites biodegradable matrixes

    International Nuclear Information System (INIS)

    Oliveira, Francieli B. de; Teixeira, Eliangela de M.; Marconcini, Jose M.; Mattoso, Luiz H.C.; Teodoro, Kelcilene B.R.

    2009-01-01

    Cellulose nanofibers have been extracted by acid hydrolysis from sisal fibers. They are seen a good source material due to availability and low cost. The nanofibers was evaluated by thermal degradation behavior using thermogravimetry (TG), crystallinity by X-ray diffraction and morphological structure was investigated by atomic force microscopy (AFM) experiments. The resulting nanofibers was shown high crystallinity and a network of rodlike cellulose elements. The nanofibers will be incorporated as reinforcement in a biodegradable matrix and evaluated. (author)

  11. The high temperature resistivity of Ba2YCu3O7-chi

    International Nuclear Information System (INIS)

    Xingkui, Z.; Shining, Z.; Hao, W.; Shiyuan, Z.; Ningshen, Z.; Ziran, X.

    1988-01-01

    The high temperature resistivity (rho), thermogravimetry (TG) and derivative thermogravimetric (DTG) have been used to characterize superconductor Ba 2 YCu 3 O 7-chi (BYCO) in O 2 , air and N 2 . The resistivity is linear from room temperature at 350 0 C and then deviate from linearity with oxygen evolution, the derivative of resistivity drho/dT increases abruptly near orthorhombic to tetragonal phase transition. These phenomena can give good explanations for a two-band Drude model

  12. Molecular structure of virgin and Tg cycled (Ag2Se)x (AsSe)1-x bulk glasses

    Science.gov (United States)

    Wachtman, Jacob; Chen, Ping; Boochand, P.

    2009-03-01

    AsSe, the base glass (x = 0) in the titled ternary, is an interesting example of a chalcogenide that is partially de-mixed into As4Se4 molecules segregated from a connected AsSe network, with the latter determining glass network properties. Raman scattering reveals sharp modes of the Realgar molecules that are superimposed on broad modes coming from of the backbone. Upon Tg cycling virgin samples (as quenched melts), the concentration of de-mixed As4Se4 molecules decreases, suggesting that thermally induced polymerization occurs; molecules break up to form part of the connective tissue. Modulated DSC experiments reveal a broad exotherm near 140 ^oC in virgin samples, which becomes nearly extinct in Tg cycled samples. The exotherm may represent Realgar molecules nano-crystallizing as the temperature approaches Tg. Compositional trends in thermal parameters such as Tg(x), δCp(x), and the δHnr(x) as a function of Ag2Se content `x' of the glasses will be reported.

  13. Comparison between TG-51 and TRS-398: electron contamination effect on photon beam-quality specification

    International Nuclear Information System (INIS)

    Medina, Antonio Lopez; Teijeiro, Antonio; Salvador, Francisco; Medal, Daniela; Vazquez, Julio; Salgado, Manuel; Carrion, MarIa C

    2004-01-01

    Two dosimetry protocols based on absorbed dose to water have recently been implemented: TG-51 and TRS-398. These protocols use different beam-quality indices. The effect of electron contamination in measurements of %dd(10) x has been proposed as a disadvantage of the TG-51. For actual measurements of %dd(10) x in five clinical beams ) a purging magnet was employed to remove the electron contamination. Also, %dd(10) x was measured in the different ways described in TG-51 for high-energy beams: with a lead foil at 50 cm from the phantom surface, at 30 cm, and for open beam. Moreover, TPR 20,10 was determined. Also, periodic quality-control measurements were used for comparing both quality indices and variation over time, but D 20,10 was used instead of TPR 20,10 and measurements in open beam for the %dd(10) x determination. Considering both protocols, S w,air and k Q were calculated in order to compare the results with the experimental data. Significant differences (0.3% for k Q ) were only found for the two high-energy beams, but when the electron contamination is underestimated by TG-51, the difference in k Q is lower. Differences in the other cases and variations over time were less than 0.1%

  14. Database Description - Open TG-GATEs Pathological Image Database | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Open TG-GATEs Pathological Image Database Database Description General information of database Database... name Open TG-GATEs Pathological Image Database Alternative name - DOI 10.18908/lsdba.nbdc00954-0...iomedical Innovation 7-6-8, Saito-asagi, Ibaraki-city, Osaka 567-0085, Japan TEL:81-72-641-9826 Email: Database... classification Toxicogenomics Database Organism Taxonomy Name: Rattus norvegi... Article title: Author name(s): Journal: External Links: Original website information Database

  15. Role of transglutaminase 2 in PAC1 receptor mediated protection against hypoxia-induced cell death and neurite outgrowth in differentiating N2a neuroblastoma cells.

    Science.gov (United States)

    Algarni, Alanood S; Hargreaves, Alan J; Dickenson, John M

    2017-03-15

    The PAC 1 receptor and tissue transglutaminase (TG2) play important roles in neurite outgrowth and modulation of neuronal cell survival. In this study, we investigated the regulation of TG2 activity by the PAC 1 receptor in retinoic acid-induced differentiating N2a neuroblastoma cells. TG2 transamidase activity was determined using an amine incorporation and a peptide cross linking assay. In situ TG2 activity was assessed by visualising the incorporation of biotin-X-cadaverine using confocal microscopy. TG2 phosphorylation was monitored via immunoprecipitation and Western blotting. The role of TG2 in PAC 1 receptor-induced cytoprotection and neurite outgrowth was investigated by monitoring hypoxia-induced cell death and appearance of axonal-like processes, respectively. The amine incorporation and protein crosslinking activity of TG2 increased in a time and concentration-dependent manner following stimulation with pituitary adenylate cyclase-activating polypeptide-27 (PACAP-27). PACAP-27 mediated increases in TG2 activity were abolished by the TG2 inhibitors Z-DON and R283 and by pharmacological inhibition of protein kinase A (KT 5720 and Rp-cAMPs), protein kinase C (Ro 31-8220), MEK1/2 (PD 98059), and removal of extracellular Ca 2+ . Fluorescence microscopy demonstrated PACAP-27 induced in situ TG2 activity. TG2 inhibition blocked PACAP-27 induced attenuation of hypoxia-induced cell death and outgrowth of axon-like processes. TG2 activation and cytoprotection were also observed in human SH-SY5Y cells. Together, these results demonstrate that TG2 activity was stimulated downstream of the PAC 1 receptor via a multi protein kinase dependent pathway. Furthermore, PAC 1 receptor-induced cytoprotection and neurite outgrowth are dependent upon TG2. These results highlight the importance of TG2 in the cellular functions of the PAC 1 receptor. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Synthesis of Non-Toxic Silica Particles Stabilized by Molecular Complex Oleic-Acid/Sodium Oleate.

    Science.gov (United States)

    Spataru, Catalin Ilie; Ianchis, Raluca; Petcu, Cristian; Nistor, Cristina Lavinia; Purcar, Violeta; Trica, Bogdan; Nitu, Sabina Georgiana; Somoghi, Raluca; Alexandrescu, Elvira; Oancea, Florin; Donescu, Dan

    2016-11-19

    The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA) and its alkaline salt (OLANa). Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA), with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na⁺ = 2:1, the molar ratio (OLA/OLANa = 1:1) required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES) was added in a sodium silicate sol-gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC) (TG-DSC) analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids' final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules.

  17. Synthesis of Non-Toxic Silica Particles Stabilized by Molecular Complex Oleic-Acid/Sodium Oleate

    Science.gov (United States)

    Spataru, Catalin Ilie; Ianchis, Raluca; Petcu, Cristian; Nistor, Cristina Lavinia; Purcar, Violeta; Trica, Bogdan; Nitu, Sabina Georgiana; Somoghi, Raluca; Alexandrescu, Elvira; Oancea, Florin; Donescu, Dan

    2016-01-01

    The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA) and its alkaline salt (OLANa). Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA), with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na+ = 2:1, the molar ratio (OLA/OLANa = 1:1) required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES) was added in a sodium silicate sol–gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC) (TG-DSC) analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids’ final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules. PMID:27869768

  18. Flexible thermoplastic composite of Polyvinyl Butyral (PVB and waste of rigid Polyurethane foam

    Directory of Open Access Journals (Sweden)

    Marilia Sônego

    2015-04-01

    Full Text Available This study reports the preparation and characterization of composites with recycled poly(vinyl butyral (PVB and residue of rigid polyurethane foam (PUr, with PUr contents of 20, 35 and 50 wt %, using an extruder equipped with a Maillefer single screw and injection molding. The components of the composites were thermally characterized using differential scanning calorimetry (DSC and thermogravimetry. The composites were evaluated by melt flow index (MFI, tensile and hardness mechanical tests and scanning electron microscopy (SEM. Tg determined by DSC of PVB sample (53 °C indicated the presence of plasticizer (Tg of pure PVB is 70 °C. MFI of the composites indicated a viscosity increase with the PUr content and, as the shear rate was held constant during injection molding, higher viscosities promoted higher shear stresses in the composites, thereby causing breaking or tearing of the PUr particles. The SEM micrographs showed low adhesion between PVB and PUr and the presence of voids, both inherent in the rigid foam and in the interphase PVB-PUr. The SEM micrographs also showed that PVB/PUr (50/50 composite exhibited the smallest particle size and a more homogeneous and compact structure with fewer voids in the interface. The stiffness of the composites increases with addition of the PUr particles, as evidenced in the mechanical tests.

  19. Study of nanocomposites based polyurethanes obtained of the biodiesel from passion fruit with fiber cashew

    International Nuclear Information System (INIS)

    Araujo, B.R.S.; Breves, R.A.; Santos, M.A.; Lopes, R.V.V.; Macedo, J.L.; Ceschin, A.M.; Sales, M.J.A.

    2014-01-01

    In this work, polyurethanes (PUs) prepared with polyol obtained of the biodiesel from passion fruit oil (BIPFO) and composites with cashew fiber 'in natura' were developed. The synthesis of polyol (PBIPFO) consisted in the epoxidation/hydroxylation of BIOM in one step, using performic acid generated 'in situ'. The instaurations the passion fruit oil (PFO) and the reactions of obtaining the BIOM and PBIOM were confirmed by nuclear magnetic resonance (NMR) "1H and infrared spectroscopy (FTIR). The PUs were prepared using PBIPFO with 4,4-diphenylmethane diisocyanate (MDI) at molar ratio [NCO]/[OH] of 1.5. PUs and composites were analyzed by FTIR, thermogravimetry (TG), derivative thermogravimetry (DTG) and dynamic mechanical analysis (DMA). The use of BIPFO as raw material to get PUs and composites with cashew fiber showed viability by success of the reactions throughout the process and properties of the materials obtained. (author)

  20. Obtaining polyester from glycerin for synthesis of polyurethanes; Obtencao de poliester a partir da glicerina para sintese de poliuretanas

    Energy Technology Data Exchange (ETDEWEB)

    Breves, Rodolfo A.; Ghesti, Grace F.; Sales, Maria J.A., E-mail: eu_sou_o_rodolfo@hotmail.com [Universidade de Brasilia (LabPol/UnB), DF (Brazil). Laboratorio de Pesquisa em Polimeros; Silva, Jessica S.; Coelho, Paulo V.M.; Lopes, Roseany V.V. [Universidade de Brasilia (UnB), DF (Brazil). Faculdade do Gama; Brioude, Michel M. [Freiburg University (Germany)

    2014-07-01

    The use of renewable resources has been increasing, due to the development of materials that have viable applications that are environmentally friendly. In this paper, a polyester was synthesized from glycerin, with the addition of adipic acid in a molar ratio of 1: 1.5, with dilauryl tin catalyst, which was added in proportions of 1 to 3% obtained PUs from castor oil (Ricinus communis) and MDI (diphenyl methane diisocyanate). The materials were characterized by infrared spectroscopy (FTIR), nuclear magnetic resonance {sup 1}H NMR, thermogravimetry (TG) and derivative thermogravimetry (DTG). The reaction for obtaining the polyester was confirmed by FTIR, the absorption band between 1708-1730 cm{sup -1} and {sup 1}H NMR, in the region 1.4 to 1.8 ppm and 2.2 to 2.6 ppm. The thermal decomposition of polyester occurred with temperature above 300 ° C. PUs showed similar thermal stability. (author)

  1. Obtaining polyester from glycerin for synthesis of polyurethanes

    International Nuclear Information System (INIS)

    Breves, Rodolfo A.; Ghesti, Grace F.; Sales, Maria J.A.

    2014-01-01

    The use of renewable resources has been increasing, due to the development of materials that have viable applications that are environmentally friendly. In this paper, a polyester was synthesized from glycerin, with the addition of adipic acid in a molar ratio of 1: 1.5, with dilauryl tin catalyst, which was added in proportions of 1 to 3% obtained PUs from castor oil (Ricinus communis) and MDI (diphenyl methane diisocyanate). The materials were characterized by infrared spectroscopy (FTIR), nuclear magnetic resonance "1H NMR, thermogravimetry (TG) and derivative thermogravimetry (DTG). The reaction for obtaining the polyester was confirmed by FTIR, the absorption band between 1708-1730 cm"-"1 and "1H NMR, in the region 1.4 to 1.8 ppm and 2.2 to 2.6 ppm. The thermal decomposition of polyester occurred with temperature above 300 ° C. PUs showed similar thermal stability. (author)

  2. Study of nanocomposites based polyurethanes obtained of the biodiesel from passion fruit with fiber cashew; Estudo de nanocompositos de poliuretanas obtidas do biodiesel do oleo de maracuja com a fibra de caju

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, B.R.S.; Breves, R.A.; Santos, M.A.; Lopes, R.V.V.; Macedo, J.L.; Ceschin, A.M.; Sales, M.J.A., E-mail: brendabetas2@gmail.com [Universidade de Brasilia (UnB), Brasilia, DF (Brazil)

    2014-07-01

    In this work, polyurethanes (PUs) prepared with polyol obtained of the biodiesel from passion fruit oil (BIPFO) and composites with cashew fiber 'in natura' were developed. The synthesis of polyol (PBIPFO) consisted in the epoxidation/hydroxylation of BIOM in one step, using performic acid generated 'in situ'. The instaurations the passion fruit oil (PFO) and the reactions of obtaining the BIOM and PBIOM were confirmed by nuclear magnetic resonance (NMR) {sup 1}H and infrared spectroscopy (FTIR). The PUs were prepared using PBIPFO with 4,4-diphenylmethane diisocyanate (MDI) at molar ratio [NCO]/[OH] of 1.5. PUs and composites were analyzed by FTIR, thermogravimetry (TG), derivative thermogravimetry (DTG) and dynamic mechanical analysis (DMA). The use of BIPFO as raw material to get PUs and composites with cashew fiber showed viability by success of the reactions throughout the process and properties of the materials obtained. (author)

  3. Synthesis, characterization and thermal behavior of rare earth amido sulfonates; Sintese, caracterizacao e comportamento termico de amidossulfonatos de terras raras

    Energy Technology Data Exchange (ETDEWEB)

    Luiz, Jose Marques; Nunes, Ronaldo Spezia, E-mail: jmluiz@feg.unesp.br [Universidade Estadual Paulista Julio Mesquita Filho (UNESP), Guaratingueta, SP (Brazil). Faculdade de Engenharia. Departamento de Fisica e Quimica; Matos, Jivaldo do Rosario [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Quimica

    2013-09-01

    Hydrated compounds prepared in aqueous solution by reaction between amidosulfonic acid [H{sub 3}NSO{sub 3}] and suspensions of rare earth hydroxycarbonates [Ln{sub 2}(OH){sub x}(CO{sub 3}){sub y}.zH{sub 2}O] were characterized by elemental analysis (% Ln, % N and % H), infrared spectroscopy (FTIR) and thermogravimetry (TG). The compounds presented the stoichiometry Ln(NH{sub 2}SO{sub 3}){sub 3}.xH{sub 2}O (where x = 1, 5, 2.0 or 3.0). The IR spectra showed absorptions characteristic of H{sub 2}O molecules and NH{sub 2}SO{sub 3} groups. Degree of hydration, thermal decomposition steps and formation of stable intermediates of the type [Ln{sub 2}(SO{sub 4}){sub 3}] and (Ln{sub 2}O{sub 2}SO{sub 4}), besides formation of their oxides, was determined by thermogravimetry. (author)

  4. TgICMAP1 is a novel microtubule binding protein in Toxoplasma gondii.

    Directory of Open Access Journals (Sweden)

    Aoife T Heaslip

    Full Text Available The microtubule cytoskeleton provides essential structural support for all eukaryotic cells and can be assembled into various higher order structures that perform drastically different functions. Understanding how microtubule-containing assemblies are built in a spatially and temporally controlled manner is therefore fundamental to understanding cell physiology. Toxoplasma gondii, a protozoan parasite, contains at least five distinct tubulin-containing structures, the spindle pole, centrioles, cortical microtubules, the conoid, and the intra-conoid microtubules. How these five structurally and functionally distinct sets of tubulin containing structures are constructed and maintained in the same cell is an intriguing problem. Previously, we performed a proteomic analysis of the T. gondii apical complex, a cytoskeletal complex located at the apical end of the parasite that is composed of the conoid, three ring-like structures, and the two short intra-conoid microtubules. Here we report the characterization of one of the proteins identified in that analysis, TgICMAP1. We show that TgICMAP1 is a novel microtubule binding protein that can directly bind to microtubules in vitro and stabilizes microtubules when ectopically expressed in mammalian cells. Interestingly, in T. gondii, TgICMAP1 preferentially binds to the intra-conoid microtubules, providing us the first molecular tool to investigate the intra-conoid microtubule assembly process during daughter construction.

  5. Local confidence limits for IMRT and VMAT techniques: a study based on TG119 test suite

    International Nuclear Information System (INIS)

    Thomas, M.; Chandroth, M.

    2014-01-01

    The aim of this study was to generate a local confidence limit (CL) for intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques used at Waikato Regional Cancer Centre. This work was carried out based on the American Association of Physicists in Medicine (AAPM) Task Group (TG) 119 report. The AAPM TG 119 report recommends CLs as a bench mark for IMRT commissioning and delivery based on its multiple institutions planning and dosimetry comparisons. In this study the locally obtained CLs were compared to TG119 benchmarks. Furthermore, the same bench mark was used to test the capabilities and quality of the VMAT technique in our clinic. The TG 119 test suite consists of two primary and four clinical tests for evaluating the accuracy of IMRT planning and dose delivery systems. Pre defined structure sets contoured on computed tomography images were downloaded from AAPM website and were transferred to a locally designed phantom. For each test case two plans were generated using IMRT and VMAT optimisation. Dose prescriptions and planning objectives recommended by TG119 report were followed to generate the test plans in Eclipse Treatment Planning System. For each plan the point dose measurements were done using an ion chamber at high dose and low dose regions. The planar dose distribution was analysed for percentage of points passing the gamma criteria of 3 %/3 mm, for both the composite plan and individual fields of each plan. The CLs were generated based on the results from the gamma analysis and point dose measurements. For IMRT plans, the CLs obtained were (1) from point dose measurements: 2.49 % at high dose region and 2.95 % for the low dose region (2) from gamma analysis: 2.12 % for individual fields and 5.9 % for the composite plan. For VMAT plans, the CLs obtained were (1) from point dose measurements: 2.56 % at high dose region and 2.6 % for the low dose region (2) from gamma analysis: 1.46 % for individual fields and 0

  6. Synthesis of poly(dimethylsilylene-co-diphenylsilylene) polymers as precursors for SiC ceramics

    International Nuclear Information System (INIS)

    Bushnell-Watson, S.M.; Emsley, R.J.P.; Morris, M.J.; Sharp, J.H.

    1993-01-01

    Silicon carbide ceramics, especially fibres, are being fabricated via polymeric precursors. Although such fibres are commercially available, there is a demand for improved performance particularly at elevated temperatures. A range of copolymers has been synthesized from the monomers, dimethyldichlorosilane and diphenyldichlorosilane, by a Wurtz reaction involving dechlorination using sodium metal in xylene. The products of reaction were characterised by a range of techniques, including gel permeation chromatography (GPC), infra-red spectroscopy (IR), X-ray powder diffraction (XRD) and thermogravimetry (TG). (orig.)

  7. Microwave-assisted hydrothermal synthesis of coralloid nanostructured nickel hydroxide hydrate and thermal conversion to nickel oxide

    International Nuclear Information System (INIS)

    Lai, Teh-Long; Lai, Yuan-Lung; Yu, Jen-Wei; Shu, Youn-Yuen; Wang, Chen-Bin

    2009-01-01

    Coralloid nanostructured nickel hydroxide hydrate has been successfully synthesized by a simple microwave-assisted hydrothermal process using nickel sulfate hexahydrate as precursor and urea as hydrolysis-controlling agent. A pure coralloid nanostructured nickel oxide can be obtained from the nickel hydroxide hydrate after calcination at 400 deg. C. The thermal property, structure and morphology of samples were characterized by thermogravimetry (TG), temperature-programmed reduction (TPR), X-ray (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

  8. Microwave-assisted hydrothermal synthesis of coralloid nanostructured nickel hydroxide hydrate and thermal conversion to nickel oxide

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Teh-Long [Environmental Analysis Laboratory, Department of Chemistry, National Kaohsiung Normal University, Kaohsiung 802, Taiwan (China); Lai, Yuan-Lung [Department of Mechanical and Automation Engineering, Da-Yeh University, Changhua 515, Taiwan (China); Yu, Jen-Wei [Environmental Analysis Laboratory, Department of Chemistry, National Kaohsiung Normal University, Kaohsiung 802, Taiwan (China); Shu, Youn-Yuen, E-mail: shuyy@nknucc.nknu.edu.tw [Environmental Analysis Laboratory, Department of Chemistry, National Kaohsiung Normal University, Kaohsiung 802, Taiwan (China); Wang, Chen-Bin, E-mail: chenbin@ccit.edu.tw [Department of Applied Chemistry and Materials Science, Chung Cheng Institute of Technology, National Defense University, Tahsi, Taoyuan 335, Taiwan (China)

    2009-10-15

    Coralloid nanostructured nickel hydroxide hydrate has been successfully synthesized by a simple microwave-assisted hydrothermal process using nickel sulfate hexahydrate as precursor and urea as hydrolysis-controlling agent. A pure coralloid nanostructured nickel oxide can be obtained from the nickel hydroxide hydrate after calcination at 400 deg. C. The thermal property, structure and morphology of samples were characterized by thermogravimetry (TG), temperature-programmed reduction (TPR), X-ray (XRD), infrared spectroscopy (IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

  9. Database Description - Open TG-GATEs | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available ne expression data and predict the safety of candidate chemicals has been develop...ears of the project, more than 30 safety biomarkers were develped by using TG-GATEs. In addition, data acqui

  10. Cotinine improves visual recognition memory and decreases cortical Tau phosphorylation in the Tg6799 mice.

    Science.gov (United States)

    Grizzell, J Alex; Patel, Sagar; Barreto, George E; Echeverria, Valentina

    2017-08-01

    Alzheimer's disease (AD) is associated with the progressive aggregation of hyperphosphorylated forms of the microtubule associated protein Tau in the central nervous system. Cotinine, the main metabolite of nicotine, reduced working memory deficits, synaptic loss, and amyloid β peptide aggregation into oligomers and plaques as well as inhibited the cerebral Tau kinase, glycogen synthase 3β (GSK3β) in the transgenic (Tg)6799 (5XFAD) mice. In this study, the effect of cotinine on visual recognition memory and cortical Tau phosphorylation at the GSK3β sites Serine (Ser)-396/Ser-404 and phospho-CREB were investigated in the Tg6799 and non-transgenic (NT) littermate mice. Tg mice showed short-term visual recognition memory impairment in the novel object recognition test, and higher levels of Tau phosphorylation when compared to NT mice. Cotinine significantly improved visual recognition memory performance increased CREB phosphorylation and reduced cortical Tau phosphorylation. Potential mechanisms underlying theses beneficial effects are discussed. Copyright © 2017. Published by Elsevier Inc.

  11. Compositional characterization of carbon electrode material: A study using simultaneous TG-DTA-FTIR

    International Nuclear Information System (INIS)

    Raje, Naina; Aacherekar, Darshana A.; Reddy, A.V.R.

    2009-01-01

    Present work describes the application of thermal methods, especially the evolved gas analysis (EGA) for the compositional characterization of carbon electrode material with respect to its organic, amorphous and graphitic carbon content. Trace levels of organic carbon present in the amorphous carbon samples were determined qualitatively by using FTIR absorption spectroscopy. Amorphous and graphitic carbon content in synthetic mixture samples were determined quantitatively using simultaneous TG-DTA-FTIR measurements. FTIR system was calibrated using the measured absorption signal of the evolved carbon dioxide due to the decomposition of cadmium carbonate. Inter-comparison studies using TG-FTIR measurements show that simultaneous FTIR spectroscopy is an effective complementary quantitative measurement technique for thermogravimetric analysis involving the complex decomposition reaction processes.

  12. Notes on the implementation of the TG-43 formalism in high-rate brachytherapy; Notas sobre la implementacion del formalismo TG-43 en braquiterapia de lata tasa

    Energy Technology Data Exchange (ETDEWEB)

    Sendon del Rio, J. R.; Gonzalez Ruiz, C.; Garcia Marcos, R.; Jimenez Rojas, R.; Lopez Bote, M. A.

    2011-07-01

    The TG-43 formalism is based on dosimetric parameters depend on the specific font design extracted from dose distributions calculated by Monte Carlo in water. Relatively easy to implement, yet provides a degree of uncertainty, making it necessary to verify the calculation algorithm in the planning system to assess its behavior.

  13. Impaired hippocampal acetylcholine release parallels spatial memory deficits in Tg2576 mice subjected to basal forebrain cholinergic degeneration

    DEFF Research Database (Denmark)

    Laursen, Bettina; Mørk, Arne; Plath, Niels

    2013-01-01

    (BFCD) in 3 months old male Tg2576 mice to co-express cholinergic degeneration with Aβ overexpression as these characteristics constitutes key hallmarks of AD. At 9 months, SAP lesioned Tg2576 mice were cognitively impaired in two spatial paradigms addressing working memory and mid to long-term memory...

  14. Raman scattering boson peak and differential scanning calorimetry studies of the glass transition in tellurium-zinc oxide glasses.

    Science.gov (United States)

    Stavrou, E; Tsiantos, C; Tsopouridou, R D; Kripotou, S; Kontos, A G; Raptis, C; Capoen, B; Bouazaoui, M; Turrell, S; Khatir, S

    2010-05-19

    Raman scattering and differential scanning calorimetry (DSC) measurements have been carried out on four mixed tellurium-zinc oxide (TeO(2))(1 - x)(ZnO)(x) (x = 0.1, 0.2, 0.3, 0.4) glasses under variable temperature, with particular attention being given to the respective glass transition region. From the DSC measurements, the glass transition temperature T(g) has been determined for each glass, showing a monotonous decrease of T(g) with increasing ZnO content. The Raman study is focused on the low-frequency band of the glasses, the so-called boson peak (BP), whose frequency undergoes an abrupt decrease at a temperature T(d) very close to the respective T(g) values obtained by DSC. These results show that the BP is highly sensitive to dynamical effects over the glass transition and provides a means for an equally reliable (to DSC) determination of T(g) in tellurite glasses and other network glasses. The discontinuous temperature dependence of the BP frequency at the glass transition, along with the absence of such a behaviour by the high-frequency Raman bands (due to local atomic vibrations), indicates that marked changes of the medium range order (MRO) occur at T(g) and confirms the correlation between the BP and the MRO of glasses.

  15. Use of ionizing radiation in the recycling of unserviceable tires of automotive and its adequate environmental disposal

    International Nuclear Information System (INIS)

    Souza, Clecia de Moura

    2013-01-01

    The aim of this study was to use ionizing radiation in the recycling of scrap tires of automotive. Samples of rubber unserviceable tires were irradiated with radiation doses 200, 400 and 600kGy in an electron accelerator. Subsequently, they were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, spectrophotometry Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). By thermogravimetry was possible to observe the effects of radiation in the mass loss of material. In the DSC curves were observed exothermic decomposition peaks and associated values of enthalpy variation (ΔH). The mechanical properties of the elastomeric matrix with unserviceable tires powder were studied and its behavior to ionizing radiation was analyzed. FTIR spectra were obtained in the 4000 - 650cm-1 region. It was observed that there was no change in the peaks due irradiation. For SEM the micrographs were enlarged from 32 times up to 1000 times and observed in sizes from 1mm up to 20μm. It was observed at doses of 200 and 400kGy, roughness corresponding to breaks or ruptures possibly caused by radiation. In 600kGy radiation dose was observed cavities caused by radiation. It was observed that at all doses occurred degradation. For samples without powder and with 10, 30 and 50% of unserviceable tires powder it was obtained micrographs of 100μm and 200μm amplification. Also it was possible to observe the incorporation of unserviceable tires powder of automotive in the elastomeric matrix of non-irradiated and irradiated samples. (author)

  16. Use of ionizing radiation in the recycling of unserviceable tires of automotive and its adequate environmental disposal; Utilizacao da radiacao ionizante na reciclagem de pneus inserviveis de automovel e sua destinacao ambiental adequada

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Clecia de Moura

    2013-07-01

    The aim of this study was to use ionizing radiation in the recycling of scrap tires of automotive. Samples of rubber unserviceable tires were irradiated with radiation doses 200, 400 and 600kGy in an electron accelerator. Subsequently, they were characterized by thermogravimetry (TG), differential scanning calorimetry (DSC), tensile strength mechanical test, spectrophotometry Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). By thermogravimetry was possible to observe the effects of radiation in the mass loss of material. In the DSC curves were observed exothermic decomposition peaks and associated values of enthalpy variation (ΔH). The mechanical properties of the elastomeric matrix with unserviceable tires powder were studied and its behavior to ionizing radiation was analyzed. FTIR spectra were obtained in the 4000 - 650cm-1 region. It was observed that there was no change in the peaks due irradiation. For SEM the micrographs were enlarged from 32 times up to 1000 times and observed in sizes from 1mm up to 20μm. It was observed at doses of 200 and 400kGy, roughness corresponding to breaks or ruptures possibly caused by radiation. In 600kGy radiation dose was observed cavities caused by radiation. It was observed that at all doses occurred degradation. For samples without powder and with 10, 30 and 50% of unserviceable tires powder it was obtained micrographs of 100μm and 200μm amplification. Also it was possible to observe the incorporation of unserviceable tires powder of automotive in the elastomeric matrix of non-irradiated and irradiated samples. (author)

  17. Synthesis and characterization of novel Cu(II) complex coated Fe3O4@SiO2 nanoparticles for catalytic performance

    Science.gov (United States)

    Nasrollahzadeh, Mahmoud; Sajjadi, Mohaddeseh; Khonakdar, Hossein Ali

    2018-06-01

    In this study, a convenient method for the synthesis of arylaminotetrazoles has been developed using a copper (II)-aminotetrazole complex immobilized on silica-coated Fe3O4 (Fe3O4@SiO2) nanoparticles (Fe3O4@SiO2-aminotet-Cu(II)) as a novel and efficient magnetically catalyst. The constructed superparamagnetic core-shell nanoparticles were successfully prepared, as proven using different spectroscopic techniques such as fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscope (TEM), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetry and differential thermogravimetry (TG-DTG) and vibrating sample magnetometer (VSM) analysis. The applicability of Fe3O4@SiO2-aminotet-Cu(II) magnetic catalyst allows the efficient synthesis of a variety of arylaminotetrazoles from the reaction between various arylcyanamides with sodium azide in high yields. The effect of catalyst loading was investigated. In addition, the reaction mechanism for the synthesis of arylaminotetrazoles was reasonably proposed. Results show that the 1-aryl-5-amino-1H-tetrazole (B isomer) and 5-arylamino-1H-tetrazole (A isomer) can be obtained from the arylcyanamides carrying electron-donating and electron-withdrawing substituents, respectively. This procedure offers a simple methodology, relatively short reaction times, easy work-up, high yields of the products and a cleaner reaction with elimination of hydrazoic acid (HN3). Moreover, catalyst can be conveniently recovered through the use of external magnet and reused for at least 6 times without any significant loss of its activity.

  18. Role of 18F-F.D.G. PET/CT in management of patients with differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Sibille, L.; Guillemard, S.; Eberle-Pouzeratte, M.C.; Espitalier-Riviere, C.; Faurous, P.; Artus, J.C.; Thezenas, S.; Lamy, P.J.; Rossi, M.

    2010-01-01

    18 F-F.D.G. PET/CT by combining both metabolic and anatomical information has proven to be an effective modality for detecting many types of cancer. Some differentiated forms of cancer like differentiated thyroid carcinoma (D.T.C.) are less F.D.G. avid and thus less easily detectable. Nevertheless 18 F-F.D.G. PET/CT has been proved useful in D.T.C. especially in case of suspected recurrent disease with negative whole-body radioiodine scintigraphy ( 131 I W.B.S.) and elevated thyroglobulin (Tg) or thyroglobulin autoantibodies (AbTg) levels. Impact on clinical management after 18 F-F.D.G. PET/CT examinations has been analyzed in patients with suspected recurrent D.T.C. in this retrospective study. Methodology. Fifty-five 18 F-F.D.G. PET/CT were performed in 45 patients with suspected recurrent or residual disease either because of elevated Tg/AbTg levels (n 45) or uncertain conventional imaging (n = 10) including 131 I W.B.S., cervical echography and CT scan if necessary. 18 F-F.D.G. PET/CT results were compared with histopathology and/or clinical follow-up with evaluation of impact on clinical management. Results. Twenty-nine exams were positive (53 %). There were 20 true-positive (T.P.) (14 locoregional relapses and six with distant metastases) and nine false-positive (F.P.) (all cervical). SUV max median values of hyper-metabolic foci were significantly higher in T.P. (5.1) than in F.P. (2.8). Overall, 20 (36 %) 18 F-F.D.G. PET/CT directly affected clinical management resulting in 13 (65 %) new surgical operations. Sensitivity, specificity, predictive positive value, predictive negative value and accuracy of 18 F-F.D.G. PET/CT were estimated for the whole group (respectively 83 %, 71 %, 69 %, 85 % and 76 %) and for two subgroups depending on Tg level (less or more than 1.2 ng/ml). Discussion and conclusion. 18 F-F.D.G. PET/CT is a powerful and useful tool in patients with suspected D.T.C. recurrence or residual disease and should be systematically performed when

  19. Helhetsorienterad utvärdering av kollektivtrafikåtgärder

    DEFF Research Database (Denmark)

    Hiselius, Lena Winslott; Barfod, Michael Bruhn; Leleur, Steen

    Under hösten 2008 och våren 2009 har forskare vid Avd. Trafik och väg vid Lunds Tekniska Högskola, DTU Transport vid Danmarks Tekniska Universitet samt National-ekonomiska institutionen vid Lunds Universitet genomfört ett forskningsprojekt med syfte att studera tillämpningen av en sammansatt...... (helhetsorienterad) analys av kollektiv-trafikåtgärder....

  20. Kinetic analysis of overlapping multistep thermal decomposition comprising exothermic and endothermic processes: thermolysis of ammonium dinitramide.

    Science.gov (United States)

    Muravyev, Nikita V; Koga, Nobuyoshi; Meerov, Dmitry B; Pivkina, Alla N

    2017-01-25

    This study focused on kinetic modeling of a specific type of multistep heterogeneous reaction comprising exothermic and endothermic reaction steps, as exemplified by the practical kinetic analysis of the experimental kinetic curves for the thermal decomposition of molten ammonium dinitramide (ADN). It is known that the thermal decomposition of ADN occurs as a consecutive two step mass-loss process comprising the decomposition of ADN and subsequent evaporation/decomposition of in situ generated ammonium nitrate. These reaction steps provide exothermic and endothermic contributions, respectively, to the overall thermal effect. The overall reaction process was deconvoluted into two reaction steps using simultaneously recorded thermogravimetry and differential scanning calorimetry (TG-DSC) curves by considering the different physical meanings of the kinetic data derived from TG and DSC by P value analysis. The kinetic data thus separated into exothermic and endothermic reaction steps were kinetically characterized using kinetic computation methods including isoconversional method, combined kinetic analysis, and master plot method. The overall kinetic behavior was reproduced as the sum of the kinetic equations for each reaction step considering the contributions to the rate data derived from TG and DSC. During reproduction of the kinetic behavior, the kinetic parameters and contributions of each reaction step were optimized using kinetic deconvolution analysis. As a result, the thermal decomposition of ADN was successfully modeled as partially overlapping exothermic and endothermic reaction steps. The logic of the kinetic modeling was critically examined, and the practical usefulness of phenomenological modeling for the thermal decomposition of ADN was illustrated to demonstrate the validity of the methodology and its applicability to similar complex reaction processes.

  1. The relationship between the Tg depression and the speeding up of physical aging in polystyrene/gold nanocomposites

    Science.gov (United States)

    Boucher, Virginie M.; Cangialosi, Daniele; Alegria, Angel; Colmenero, Juan

    2011-03-01

    The effect of gold nanoparticles on the segmental dynamics, glass transition (Tg) and physical aging of polystyrene (PS) was studied in PS/Gold nanocomposites samples containing 5 and 15 wt.% of 60 nm spherical gold nanoparticles, surface-treated with thiolated-PS. While the segmental dynamics of PS, as assessed by broadband dielectric spectroscopy (BDS), was found to be unchanged in presence of gold nanoparticles, the calorimetric Tg of PS was shown to decrease with increasing the amount of nanoparticles in the samples. Furthermore, the physical aging of PS, monitored by measuring the enthalpy relaxation below Tg by means of DSC, was shown to speed up with increasing the nanoparticles weight fraction, i.e. the amount of PS/Gold interface in the hybrid material. Thus, the main conclusion of our work is that PS molecular mobility and out-of-equilibrium dynamics are decoupled in these nanocomposites. The significant effect of the amount of PS/Gold interface on both the physical aging rate of PS and the calorimetric Tg depression are quantitatively accounted for by a model based on the diffusion of free volume holes towards polymer interfaces, with a diffusion coefficient depending only on the molecular mobility.

  2. Diagnostic I-131 scintigraphy in patients with differentiated thyroid cancer. No additional value of higher scan dose

    International Nuclear Information System (INIS)

    Phan, T.T.H.; Tol, K.M. van; Links, T.P.; Piers, D.A.; Vries, E.G.E. de; Dullaart, R.P.F.; Jager, P.L.

    2004-01-01

    After initial treatment with total thyroidectomy and radio iodine ablation, most follow-up protocols for patients with differentiated thyroid carcinoma contain cyclic diagnostic I-131 imaging and serum thyroglobulin (Tg) measurements. The applied diagnostic I-131 doses vary between 37 and 370 MBq. The aim of this study was to determine the yield of a diagnostic scan with 370 MBq I-131 in patients with a negative diagnostic scan with 74 MBq I-131. Retrospective evaluation of 158 patients who received a high-dose diagnostic scan with 370 MBq I-131 because of a negative low-dose diagnostic scan with 74 MBq I-131. Special attention was paid to the patients with positive high-dose diagnostic scanning and undetectable serum Tg levels after thyroid hormone withdrawal. In 127 (80%) of patients the 370 MBq I-131 scan was negative, just like the preceding low-dose scan. In 31 (20%) of patients abnormal uptake was present on the 370 MBq diagnostic scan. In 19 of these 31 patients serum Tg was undetectable. In 15/19 the high-dose diagnostic scan proved either false positive or demonstrated clinically irrelevant minor ablation rests. In only four patients (2.5%) did the high-dose diagnostic scans reveal possibly relevant uptake caused by residual differentiated thyroid cancer. In 98% of patients a 370 MBq dose of I-131 for diagnostic whole-body scintigraphy (WBS) had no additional value. The combination of a low-dose diagnostic I-131 scan using only 74 MBq combined with a serum Tg level measurement proved sufficient for correct clinical decision making regarding whether the patient requires additional I-131 therapy. (authors)

  3. Thermal decomposition of a molecular material {N(n-C4H94[FeIIFeIII(C2O43]}∞ leading to ferrite: A reaction kinetics study

    Directory of Open Access Journals (Sweden)

    Bhattacharjee Ashis

    2013-01-01

    Full Text Available A multi-step thermal decomposition of a molecular precursor, {N(n-C4H94[FeIIFeIII(C2O43}∞ has been studied using non-isothermal thermogravimetry (TG measurements in the temperature range 300 to ~800 K at multiple heating rates (5, 10 and 20 K min-1. The thermal decomposition of the oxalate-based complex proceeds stepwise through a series of intermediate reactions. Two different isoconversional methods, namely, improved iterative method and model-free method are employed to evaluate the kinetic parameters: activation energy and rate of reaction, and the most probable reaction mechanism of thermal decomposition is also determined. The different reaction pathways leading to different steps in the TG profile have also been explored which are supplemented by earlier experimental observations of the present authors.

  4. LYMPHOCYTIC THYROIDITIS IS ASSOCIATED WITH INCREASED NUMBER OF BENIGN CERVICAL NODES AND FEWER CENTRAL NECK COMPARTMENT METASTATIC LYMPH NODES IN PATIENTS WITH DIFFERENTIATED THYROID CANCER.

    Science.gov (United States)

    Donangelo, Ines; Walts, Ann E; Bresee, Catherine; Braunstein, Glenn D

    2016-10-01

    Whether or not autoimmune thyroid disease influences the progression of differentiated thyroid cancer (DTC) remains controversial. Findings of previous studies are influenced by lead time bias and/or procedure bias selection. These biases can be reduced by studying a single-institution patient population that underwent a similar extent of surgical resection. From a cohort of 660 patients with DTC who underwent thyroidectomy, we retrospectively studied 357 patients who underwent total thyroidectomy and central compartment node dissection (CCND) for DTC between 2003 and 2013. Forty-one percent (140/345) of study patients had lymphocytic thyroiditis (LT), and 30% (91/301) had serum positive for thyroglobulin antibody (TgAb). LT was reported in 78% of the TgAb-positive cases. Sixty percent (213/357) of cases had metastatic thyroid carcinoma in 1 or more neck lymph nodes (55% [198/357] central compartment, and 22% [77/356] lateral compartment). Patients with LT had fewer metastatic cervical lymph nodes than those with no LT (2.7 ± 4.7 vs 3.5 ± 4.8, respectively, P = .0285). Patients with positive TgAb and thyroiditis had a larger number of benign cervical lymph nodes removed than those with negative TgAb or no LT. No significant difference was observed in age, tumor size, multifocality, extrathyroidal extension, vascular invasion, or frequency of cervical lymph node metastasis between TgAb-negative and -positive cases or between cases with and without LT. Lymphocytic thyroiditis is associated with fewer central neck compartment metastatic lymph nodes and a larger number of excised reactive benign cervical lymph nodes. Whether this association indicates a protective role of thyroid autoimmunity in lymph node spreading remains unclear. CCND = central compartment node dissection DTC = differentiated thyroid cancer HT = Hashimoto thyroiditis LT = lymphocytic thyroiditis TgAb = thyroglobulin antibody TPO = thyroid peroxidase.

  5. Cerebrospinal fluid neurofilament light chain as a biomarker of neurodegeneration in the Tg4510 and MitoPark mouse models

    DEFF Research Database (Denmark)

    Clement, Amalie; Mitchelmore, Cathy; Andersson, Daniel

    2017-01-01

    examined whether changes in NF-L levels in brain, plasma, and CSF reflect the changing disease status of preclinical models of neurodegeneration. Using Western Blot and ELISA we characterized NF-L and disease-related proteins in brain, CSF and plasma samples from Tg4510 mice (tauopathy/AD), MitoPark mice...... (PD), and their age-matched control littermates. We found that CSF NF-L clearly discriminates Tg4510 from control littermates, which was not observed for the MitoPark model. However, both Tg4510 and MitoPark showed altered expression and solubilization of NFs compared to control littermates. We found...

  6. miR-378 attenuates muscle regeneration by delaying satellite cell activation and differentiation in mice.

    Science.gov (United States)

    Zeng, Ping; Han, Wanhong; Li, Changyin; Li, Hu; Zhu, Dahai; Zhang, Yong; Liu, Xiaohong

    2016-09-01

    Skeletal muscle mass and homeostasis during postnatal muscle development and regeneration largely depend on adult muscle stem cells (satellite cells). We recently showed that global overexpression of miR-378 significantly reduced skeletal muscle mass in mice. In the current study, we used miR-378 transgenic (Tg) mice to assess the in vivo functional effects of miR-378 on skeletal muscle growth and regeneration. Cross-sectional analysis of skeletal muscle tissues showed that the number and size of myofibers were significantly lower in miR-378 Tg mice than in wild-type mice. Attenuated cardiotoxin-induced muscle regeneration in miR-378 Tg mice was found to be associated with delayed satellite cell activation and differentiation. Mechanistically, miR-378 was found to directly target Igf1r in muscle cells both in vitro and in vivo These miR-378 Tg mice may provide a model for investigating the physiological and pathological roles of skeletal muscle in muscle-associated diseases in humans, particularly in sarcopenia. © The Author 2016. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Effects of heating rate on slow pyrolysis behavior, kinetic parameters and products properties of moso bamboo.

    Science.gov (United States)

    Chen, Dengyu; Zhou, Jianbin; Zhang, Qisheng

    2014-10-01

    Effects of heating rate on slow pyrolysis behaviors, kinetic parameters, and products properties of moso bamboo were investigated in this study. Pyrolysis experiments were performed up to 700 °C at heating rates of 5, 10, 20, and 30 °C/min using thermogravimetric analysis (TGA) and a lab-scale fixed bed pyrolysis reactor. The results show that the onset and offset temperatures of the main devolatilization stage of thermogravimetry/derivative thermogravimetry (TG/DTG) curves obviously shift toward the high-temperature range, and the activation energy values increase with increasing heating rate. The heating rate has different effects on the pyrolysis products properties, including biochar (element content, proximate analysis, specific surface area, heating value), bio-oil (water content, chemical composition), and non-condensable gas. The solid yields from the fixed bed pyrolysis reactor are noticeably different from those of TGA mainly because the thermal hysteresis of the sample in the fixed bed pyrolysis reactor is more thorough. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung; Kao Pan-Fu; Huang Miau-Ju

    1998-01-01

    Radioactive iodine ( 131 I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201 Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131 I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201 Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131 I and 201 Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201 Tl and 131 I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201 Tl imaging was performed before the 131 I studies. Of the 62 patients who underwent 201 Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201 Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131 I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201 Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201 Tl scans, 11 had positive findings on 131 I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131 I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201 Tl and 131 I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung

  9. Citalopram Ameliorates Impairments in Spatial Memory and Synaptic Plasticity in Female 3xTgAD Mice

    Directory of Open Access Journals (Sweden)

    Zhang Wei

    2017-01-01

    Full Text Available Alzheimer’s disease (AD is the primary cause of dementia. There is no effective treatment. Amyloid-β peptide (Aβ plays an important role in the pathogenesis and thus strategies suppressing Aβ production and accumulation seem promising. Citalopram is an antidepressant drug and can decrease Aβ production and amyloid plaques in transgenic mice of AD and humans. Whether citalopram can ameliorate memory deficit was not known yet. We tested the effects of citalopram on behavioral performance and synaptic plasticity in female 3xTgAD mice, a well-characterized model of AD. Mice were treated with citalopram or water from 5 months of age for 3 months. Citalopram treatment at approximately 10 mg/kg/day significantly improved spatial memory in the Morris water maze (MWM test, while not affecting anxiety-like and depression-like behavior in 3xTgAD mice. Further, hippocampal long-term potentiation (LTP impairment in 3xTgAD mice was reversed by citalopram treatment. Citalopram treatment also significantly decreased the levels of insoluble Aβ40 in hippocampal and cortical tissues in 3xTgAD mice, accompanied with a reduced amyloid precursor protein (APP. Together, citalopram treatment may be a promising strategy for AD and further clinical trials should be conducted to verify the effect of citalopram on cognition in patients with AD or mild cognitive impairment.

  10. TG13 current terminology, etiology, and epidemiology of acute cholangitis and cholecystitis

    NARCIS (Netherlands)

    Kimura, Yasutoshi; Takada, Tadahiro; Strasberg, Steven M.; Pitt, Henry A.; Gouma, Dirk J.; Garden, O. James; Büchler, Markus W.; Windsor, John A.; Mayumi, Toshihiko; Yoshida, Masahiro; Miura, Fumihiko; Higuchi, Ryota; Gabata, Toshifumi; Hata, Jiro; Gomi, Harumi; Dervenis, Christos; Lau, Wan-Yee; Belli, Giulio; Kim, Myung-Hwan; Hilvano, Serafin C.; Yamashita, Yuichi

    2013-01-01

    While referring to the evidence adopted in the Tokyo Guidelines 2007 (TG07) as well as subsequently obtained evidence, further discussion took place on terminology, etiology, and epidemiological data. In particular, new findings have accumulated on the occurrence of symptoms in patients with

  11. Effect of Sodium Selenate on Hippocampal Proteome of 3×Tg-AD Mice-Exploring the Antioxidant Dogma of Selenium against Alzheimer's Disease.

    Science.gov (United States)

    Iqbal, Javed; Zhang, Kaoyuan; Jin, Na; Zhao, Yuxi; Liu, Qiong; Ni, Jiazuan; Shen, Liming

    2018-04-19

    Selenium (Se), an antioxidant trace element, is an important nutrient for maintaining brain functions and is reported to be involved in Alzheimer's disease (AD) pathologies. The present study has been designed to elucidate the protein changes in hippocampus of 3×Tg-AD mice after supplementing sodium selenate as an inorganic source of selenium. By using iTRAQ proteomics technology, 113 differentially expressed proteins (DEPs) are found in AD/WT mice with 37 upregulated and 76 downregulated proteins. Similarly, in selenate-treated 3×Tg-AD (ADSe/AD) mice, 115 DEPs are found with 98 upregulated and 17 downregulated proteins. The third group of mice (ADSe/WT) showed 75 DEPs with 46 upregulated and 29 downregulated proteins. Among these results, 42 proteins (40 downregulated and 2 upregulated) in the diseased group showed reverse expression when treated with selenate. These DEPs are analyzed with different bioinformatics tools and are found associated with various AD pathologies and pathways. Based on their functions, selenate-reversed proteins are classified as structural proteins, metabolic proteins, calcium regulating proteins, synaptic proteins, signaling proteins, stress related proteins, and transport proteins. Six altered AD associated proteins are successfully validated by Western blot analysis. This study shows that sodium selenate has a profound effect on the hippocampus of the triple transgenic AD mice. This might be established as an effective therapeutic agent after further investigation.

  12. AIR QUALITY IN THE CITY OF TG JIU

    Directory of Open Access Journals (Sweden)

    Adina TĂTAR

    2014-05-01

    Full Text Available One of the most important problems of the modern age is the air pollution. Within this work I realized a description of Tgjiu City: geographic location, climate, hydrographical network, variations in temperature, terrain, sources of pollution. On the basis of registered values for the air quality indicator, sedimentable powders, and interpretation of results on the basis of the provisions of the standards in force, the comments were made in relation to particulate air pollution in the city area of sedimentableTg Jiu, identifying the polluters in the area, the proposed solutions for the reduction of pollution.

  13. Abnormal three-steplike sub-Tg enthalpy relaxation pattern in hyperquenched metallic glasses

    DEFF Research Database (Denmark)

    Hu, Lina; Yue, Yuanzheng

    Our recent work observed a quite different relaxation pattern, i.e., the abnormal three-steplike sub-Tg relaxation in CuZrAl GRs[1]. However, the generality and the origin of this remarkable thermodynamic anomaly remain enigmatic. By hyperquenching strategy, the present work investigated the depe......Our recent work observed a quite different relaxation pattern, i.e., the abnormal three-steplike sub-Tg relaxation in CuZrAl GRs[1]. However, the generality and the origin of this remarkable thermodynamic anomaly remain enigmatic. By hyperquenching strategy, the present work investigated...... in La55Al25Ni20 GRs. However, the correlation between Tf and the activation energy for initiating the energy releasing during thermal scanning is three-steplike for La55Al25Ni20, revealing the similar phenomenon with the abnormal ERP of Cu46Zr46Al8. These unexpected phenomena have been well explained...

  14. Differentiated thyroid cancer lymph-node relapse. Role of adjuvant radioactive iodine therapy after lymphadenectomy

    Energy Technology Data Exchange (ETDEWEB)

    Piccardo, Arnoldo; Bottoni, Gianluca; Dib, Bassam; Altrinetti, Vania; Massollo, Michela; Bossert, Irene; Cabria, Manlio [E.O. Ospedali Galliera, Department of Nuclear Medicine, Genoa (Italy); Puntoni, Matteo [Galliera Hospital, Clinical Trial Unit, Office of the Scientific Director, Genoa (Italy); Treglia, Giorgio; Giovanella, Luca [Oncology Institute of Southern Switzerland, Department of Nuclear Medicine and PET/CT Centre, Bellinzona (Switzerland); Foppiani, Luca [Galliera Hospital, Internal Medicine, Genoa (Italy); Bertoli, Mattia; Bertagna, Francesco [University of Brescia and Spedali Civili di Brescia, Department of Nuclear Medicine, Brescia (Italy); Catrambone, Ugo; Arlandini, Anselmo [Galliera Hospital, Department of Surgery, Thyroid Centre, Genoa (Italy)

    2017-06-15

    Our purpose as to evaluate the impact of adjuvant radioactive iodine therapy (RAI) on prognosis, as assessed by progression-free survival (PFS) and overall survival (OS), in patients affected by differentiated thyroid carcinoma (DTC) lymph-node relapse and previously treated with lymphadenectomy. We retrospectively evaluated DTC patients treated with lymph-node dissection for disease relapse. All patients had previously undergone total thyroidectomy and radioiodine remnant ablation (RRA). We used clinical and histological data obtained during follow-up to assess response and outcome. By means of univariate and multivariate time-to-event analyses, we assessed the impact of RAI on outcome (PFS and OS) and the prognostic role of thyroglobulin (Tg) levels under suppression with levothyroxine (Tg-on) measured 1-3 months after lymphadenectomy and of other risk factors. We evaluated 113 patients (age at diagnosis: median 41 years, interquartile range: 31-59), 64 of whom were treated with RAI. Over a median follow-up time of 5.7 years, 27 patients showed disease progression and 13 died. Kaplan-Meier PFS and OS curves showed that age on diagnosis, tumor histology, tumor size, DTC aggressive variant, and Tg-on were associated with prognosis. Patients with Tg-on ≥1 ng/ml treated with RAI showed a better PFS (Log-rank pp 0.001) and OS (p = 0.005) than untreated patients, while no effect of RAI was observed in patients with Tg-on <1 ng/ml. Multivariate models showed that age, Tg-on (≥1 vs. < 1 ng/ml, HR: 18.2, 95% CI: 5.09-64.8, p = 0.001) and RAI (Yes vs. No, HR: 0.36,95%CI: 0.15-0. 9, p = 0.02) remained the only independent factors associated with PFS, but only age and Tg-on remained significantly associated with OS (HR: 8.31, 95%CI:1.56-44.3, p = 0.01). Nonetheless, patients treated with RAI showed a lower risk of mortality (HR: 0.34, 95%CI: 0.1-1.15 p = 0.08) than untreated patients. RAI after lymphadenectomy for DTC relapse is significantly associated with better PFS

  15. Ability of the rhTSH stimulation test to predict relapse in patients with differentiated thyroid carcinoma, after long-term follow-up

    Science.gov (United States)

    MARCELINO, MAFALDA; LOPES, ANA FILIPA; MADUREIRA, DEOLINDA; FERREIRA, TERESA C.; LIMBERT, EDWARD; LEITE, VALERIANO

    2015-01-01

    The analysis of serum thyroglobulin (Tg) following thyroid-stimulating hormone (TSH) stimulation (sTg) has been recommended in the follow-up of differentiated thyroid carcinoma (DTC) patients, however, its routine use remains controversial. The aim of the current study was to evaluate the accuracy of sTg testing following recombinant human (rh) TSH stimulation in DTC patients, with a follow-up of 12.4 years. Retrospective studies were conducted of 125 DTC patients, who underwent rhTSH stimulation testing between 1999 and 2002. The exclusion criteria were: Patients with anti-Tg antibodies, Tg levels >1 ng/ml under TSH suppression and the absence of radioactive iodine (RAI) ablation therapy following surgery. In total, 49 patients were included in the study and all had been previously treated with total or near total thyroidectomy (with or without central neck dissection) and RAI, postoperatively. The Tg functional sensitivity was 1.0 ng/ml. The follow-up for patients was performed annually. During the median follow-up of 12.4 years after the rhTSH stimulation test, nine patients exhibited recurrence (18.4%). Of the nine patients, six exhibited sTg levels >2 ng/ml (positive result) and three exhibited levels <2 ng/ml (negative result). Relapse occurred at a mean of 5.9 years following the rhTSH stimulation test. The positive predictive value and negative predictive value (NPV) of positive sTg were 50 and 91.9%, respectively, with a sensitivity of 66.6% and a specificity of 85.0%. The rhTSH-stimulated Tg levels have a high NPV, allowing the identification of the patients who are free of the tumour. These results are consistent with the previously published data; however, to the best of our knowledge, this is the study with the longest follow-up duration after rhTSH stimulation. PMID:25663898

  16. Exercise alters the immune profile in Tg2576 Alzheimer mice toward a response coincident with improved cognitive performance and decreased amyloid

    Directory of Open Access Journals (Sweden)

    Cribbs David H

    2008-04-01

    Full Text Available Abstract Background Inflammation is associated with Aβ pathology in Alzheimer's disease (AD and transgenic AD models. Previously, it has been demonstrated that chronic stimulation of the immune response induces pro-inflammatory cytokines IL-1β and TNF-α which contribute to neurodegeneration. However, recent evidence has shown that inducing the adaptive immune response reduces Aβ pathology and is neuroprotective. Low concentrations of IFN-γ modulate the adaptive immune response by directing microglia to differentiate to antigen presenting cells. Our objective was to determine if exercise could induce a shift from the immune profile in aged (17–19 months Tg2576 mice to a response that reduces Aβ pathology. Methods TG (n = 29 and WT (n = 27 mice were divided into sedentary (SED and exercised (RUN groups. RUN animals were provided an in-cage running wheel for 3 weeks. Tissue was harvested and hippocampus and cortex dissected out. Quantitative data was analyzed using 2 × 2 ANOVA and student's t-tests. Results IL-1β and TNF-α were significantly greater in hippocampi from sedentary Tg2576 (TGSED mice than in wildtype (WTSED (p = 0.04, p = 0.006. Immune response proteins IFN-γ and MIP-1α are lower in TGSED mice than in WTSED (p = 0.03, p = 0.07. Following three weeks of voluntary wheel running, IL-1β and TNF-α decreased to levels indistinguishable from WT. Concurrently, IFN-γ and MIP-1α increased in TGRUN. Increased CD40 and MHCII, markers of antigen presentation, were observed in TGRUN animals compared to TGSED, as well as CD11c staining in and around plaques and vasculature. Additional vascular reactivity observed in TGRUN is consistent with an alternative activation immune pathway, involving perivascular macrophages. Significant decreases in soluble Aβ40 (p = 0.01 and soluble fibrillar Aβ (p = 0.01 were observed in the exercised transgenic animals. Conclusion Exercise shifts the immune response from innate to an adaptive or

  17. Cytokine-producing microglia have an altered beta-amyloid load in aged APP/PS1 Tg mice

    DEFF Research Database (Denmark)

    Babcock, Alicia A; Ilkjær, Laura; Clausen, Bettina H

    2015-01-01

    of CD11b, TNF, and IL-1Ra. Cytokine production and Aβ load were assessed in neocortical CD11b(+)(CD45(+)) microglia by flow cytometry. Whereas most microglia in aged mice produced IL-1Ra, relatively low proportions of microglia produced TNF, IL-1α, and IL-1β. However, microglial production......, however the inter-relationship between these processes is poorly understood. Here we show that % Aβ plaque load followed a sigmoidal trajectory with age in the neocortex of APPswe/PS1ΔE9 Tg mice, and correlated positively with soluble Aβ40 and Aβ42. Aβ measures were moderately correlated with mRNA levels...... of these latter cytokines was generally increased in APP/PS1 Tg mice. Microglia that phagocytosed endogenously-produced Aβ were only observed in APP/PS1 Tg mice. Differences in phagocytic index and total Aβ load were observed in microglia with specific cytokine profiles. Both phagocytic index and total Aβ load...

  18. Recovery of α-Al{sub 2}O{sub 3} from ionizing radiation dosimetric sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sanches, Edgar Aparecido, E-mail: sanches.ufam@gmail.com [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Dept. de Fisica; Costalonga, Ademir Geraldo Cavallari; Mascarenhas, Yvonne Primerano [Universidade de Sao Paulo (IFSC/USP), Sao Carlos, SP (Brazil). Institute de Fisica; Nascimento, Luana de Freitas [Belgium Nuclear Research Centre, SCK-CEN, Mol (Belgium); Mascarenhas, Yvone Maria [SAPRA S/A Servico de Assessoria e Protecao Radiologica, Sao Carlos, SP, (Brazil)

    2015-01-15

    Corundum, sapphire or α-Al{sub 2}O{sub 3} is an important technological material in many optical and electronic applications such as solid-state lasers, optical windows and, more recently, as a radiation detector. Landauer (Glenwood, IL, USA) accumulated large number of archived and stored Luxel™ dosemeters composed of Al{sub 2}O{sub 3}:C, which were subjected to a recovery process. Due to the importance of this advanced crystalline material in OSL dosimetry, a recovery process was developed based on the dosemeters calcination and Al{sub 2}O{sub 3}:C has been reused in manufacturing of new dosemeters. This paper does not aim to optimize the recovery process, but provides an opportunity to study the involved process parameters and to recover this valuable crystalline material from used dosemeters. To the best of our knowledge no other recovery process involving this dosimetric material was described in scientific literature. Fourier Transform Infrared Spectrometry (FTIR), Thermogravimetry/Differential Thermoanalysis (TG/DTA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), Optically Stimulated Luminescence (OSL) and Rietveld Refinement were used to characterize the recovered material and to check for the stability of its structural and dosimetric properties. (author)

  19. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlândia-MG, Brazil

    International Nuclear Information System (INIS)

    Oliveira Silva, Jader de; Filho, Guimes Rodrigues; Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Júlia Graciele; Vieira da Silva, Cleuzilene; Alves Cerqueira, Daniel

    2012-01-01

    Highlights: ► In this study, the sludge was characterized by thermal analyses and FTIR. ► The superior calorific value of the sludge was 16.2 MJ kg −1 . ► The sludge showed a significant biodegradable portion of 65%. ► The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlândia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg −1 was found, which is within the range of values reported in the literature.

  20. Global Threat Reduction Initiative Fuel Thermo-Physical Characterization Project: Sample Management Plan

    Energy Technology Data Exchange (ETDEWEB)

    Casella, Amanda J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pereira, Mario M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steen, Franciska H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-01-01

    This sample management plan provides guidelines for sectioning, preparation, acceptance criteria, analytical path, and end-of-life disposal for the fuel element segments utilized in the Global Threat Reduction Initiative (GTRI), Fuel Thermo-Physical Characterization Project. The Fuel Thermo-Physical Characterization Project is tasked with analysis of irradiated Low Enriched Uranium (LEU) Molybdenum (U-Mo) fuel element samples to support the GTRI conversion program. Sample analysis may include optical microscopy (OM), scanning electron microscopy (SEM) fuel-surface interface analysis, gas pycnometry (density) measurements, laser flash analysis (LFA), differential scanning calorimetry (DSC), thermogravimetry and differential thermal analysis with mass spectroscopy (TG /DTA-MS), Inductively Coupled Plasma Spectrophotometry (ICP), alpha spectroscopy, and Thermal Ionization Mass Spectroscopy (TIMS). The project will utilize existing Radiochemical Processing Laboratory (RPL) operating, technical, and administrative procedures for sample receipt, processing, and analyses. Test instructions (TIs), which are documents used to provide specific details regarding the implementation of an existing RPL approved technical or operational procedure, will also be used to communicate to staff project specific parameters requested by the Principal Investigator (PI). TIs will be developed, reviewed, and issued in accordance with the latest revision of the RPL-PLN-700, RPL Operations Plan. Additionally, the PI must approve all project test instructions and red-line changes to test instructions.

  1. Dosimetric and radiobiological comparison of TG-43 and Monte Carlo calculations in 192Ir breast brachytherapy applications.

    Science.gov (United States)

    Peppa, V; Pappas, E P; Karaiskos, P; Major, T; Polgár, C; Papagiannis, P

    2016-10-01

    To investigate the clinical significance of introducing model based dose calculation algorithms (MBDCAs) as an alternative to TG-43 in 192 Ir interstitial breast brachytherapy. A 57 patient cohort was used in a retrospective comparison between TG-43 based dosimetry data exported from a treatment planning system and Monte Carlo (MC) dosimetry performed using MCNP v. 6.1 with plan and anatomy information in DICOM-RT format. Comparison was performed for the target, ipsilateral lung, heart, skin, breast and ribs, using dose distributions, dose-volume histograms (DVH) and plan quality indices clinically used for plan evaluation, as well as radiobiological parameters. TG-43 overestimation of target DVH parameters is statistically significant but small (less than 2% for the target coverage indices and 4% for homogeneity indices, on average). Significant dose differences (>5%) were observed close to the skin and at relatively large distances from the implant leading to a TG-43 dose overestimation for the organs at risk. These differences correspond to low dose regions (<50% of the prescribed dose), being less than 2% of the prescribed dose. Detected dosimetric differences did not induce clinically significant differences in calculated tumor control probabilities (mean absolute difference <0.2%) and normal tissue complication probabilities. While TG-43 shows a statistically significant overestimation of most indices used for plan evaluation, differences are small and therefore not clinically significant. Improved MBDCA dosimetry could be important for re-irradiation, technique inter-comparison and/or the assessment of secondary cancer induction risk, where accurate dosimetry in the whole patient anatomy is of the essence. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  2. Thermochemical measurements and assessment of the phase diagrams in the system Y-Ba-Cu-O

    International Nuclear Information System (INIS)

    Boudene, A.; Mohammad, A.

    1996-01-01

    The aim of this project was to provide a self-consistent set of Gibbs energy data for all phases in the system Y-Ba-Cu-O. Experimental thermochemical investigations by differential thermal analysis (DTA), thermogravimetry (TG), electromotive force measurements (EMF), oxygen coulometric titration (OCT), drop and solution calorimetry, and conventional phase analysis (annealing, quenching, and X-ray diffraction [XRD]) as well as ab initio calculations of interaction energies for the 123 phase have been carried out. The experimental information (phase equilibria, heat capacity, enthalpies of formation, oxygen partial pressures, and so forth) has been used in computer-based assessments of the Gibbs energies. These data have been employed to generate phase diagrams by way of equilibrium computations. All binary and ternary subsystems have been fully assessed. For the quaternary system a dataset covering the subsolidus range has been derived. Applications of the data to practical questions, such as the production of 123 superconductors by an MOCVD process, the producibility of metallic precursors, and the oxidation of a copper-enriched stoichiometric oxide precursor, are demonstrated

  3. A study on the phase transformation of the nanosized hydroxyapatite synthesized by hydrolysis using in situ high temperature X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Shih, W.-J. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan, 70101, Taiwan (China); Wang, J.-W. [Department of Enviromental and Safety Engineering, Chung Hwa College of Medical Technology, 89 Wen-Hua 1st St., Rende Shiang, Tainan, 71703, Taiwan (China); Wang, M.-C. [Department of Materials Science and Engineering, National United University, 1 Lien-Da, Kung-Ching Li, Miao Li 360, Taiwan (China)]. E-mail: mcwang@nuu.edu.tw; Hon, M.-H. [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan, 70101, Taiwan (China); Dayeh University, 112 Shan-Jiau Road, Da-Tsuen, Changhua 515, Taiwan (China)

    2006-09-15

    The biodegradable hydroxyapatite (HA) was synthesized by hydrolysis and characterized using high temperature X-ray diffraction (HT-XRD), differential thermal analysis and thermogravimetry (DTA/TG), and scanning electron microscopy (SEM). The in situ phase transformation of the HA synthesized from CaHPO{sub 4}.2H{sub 2}O (DCPD) and CaCO{sub 3} with a Ca / P = 1.5 in 2.5 M NaOH{sub (aq)} at 75 deg. C for 1 h was investigated by HT-XRD between 25 and 1500 deg. C. The HA was crystallized at 600 deg. C and maintained as the major phase until 1400 deg. C. The HA steadily transformed to the {alpha}-tricalcium phosphate ({alpha}-TCP) which became the major phosphate phase at 1500 deg. C. At 700 deg. C, the minor CaO phase appeared and vanished at 1300 deg. C. The Na{sup +} impurity from the hydrolysis process was responsible for the formation of the NaCaPO{sub 4} phase, which appeared above 800 deg. C and disappeared at 1200 deg. C.

  4. Physicochemical changes taking place in bovine globulins under the influence of gamma irradiation studied by thermal analysis

    International Nuclear Information System (INIS)

    Ciesla, K.; Vansant, E.F.

    2006-01-01

    Radiation modification of protein based polymers as well as the development of gamma irradiation techniques as a method of food sterilisation and preservation induces necessity of better recognition of the physicochemical changes occurring in proteins after gamma irradiation. Recently differential scanning calorimetry (DSC) was applied widely in structural studies of proteins. Also thermoanalytical methods (TG, DTG) applied for proteins pyrolysis were also found to be useful in characterisation of proteins structure and the properties of proteins containing tissues. In presented paper, the aforementioned methods were applied for investigation of the gamma irradiation influence on thermal decomposition of gamma and alpha globulins and the results were related to their structural modifications. It has been found, that irradiation influences the course of decomposition of gamma and alpha globulins. Irradiation of solid native proteins result in decreased temperature of decomposition, especially decreased temperature of the last stage. The effects of irradiation performed for water suspensions were clearly more significant. The relatively large differences between decomposition of the irradiated and non-irradiated samples were detected by DSC and thermogravimetry already after irradiation of water suspensions

  5. Microstructural transformation with heat-treatment of aluminum hydroxide with gibbsite structure

    International Nuclear Information System (INIS)

    Mitsui, Tomohiro; Matsui, Toshiaki; Eguchi, Koichi; Kikuchi, Ryuji

    2009-01-01

    Aluminum hydroxide with gibbsite structure was prepared, and the microstructural transformation of the sample heat-treated at various temperatures was investigated. The sample was characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), thermogravimetry and differential thermal analysis (TG-DTA), and BET surface area. The shape of the grains in the prepared sample was hexagonal prism-like morphology. The prepared sample kept a metastable state of alumina phase at higher temperatures than the commercially available gibbsite powders. The prepared gibbsite grains underwent characteristic structural change depending on the calcination temperature. The transformation of the surface morphology was initiated at 400degC, leading to the formation of cracks with the direction parallel to the basal plane. After calcination at 1200degC, a large number of grooves were formed on the surface of the lateral planes. The specific structural change of gibbsite induced by the heat treatment was strongly related to the topotactic dehydration from gibbsite and subsequent phase transition to aluminum oxides. (author)

  6. Effect of the Cationic Block Structure on the Characteristics of Sludge Flocs Formed by Charge Neutralization and Patching

    Directory of Open Access Journals (Sweden)

    Huaili Zheng

    2017-05-01

    Full Text Available In this study, a template copolymer (TPAA of (3-Acrylamidopropyl trimethylammonium chloride (AATPAC and acrylamide (AM was successfully synthesized though ultrasonic-initiated template copolymerization (UTP, using sodium polyacrylate (PAAS as a template. TPAA was characterized by an evident cationic microblock structure which was observed through the analyses of the reactivity ratio, Fourier transform infrared spectroscopy (FTIR, 1H (13C nuclear magnetic resonance spectroscopy (1H (13C NMR, and thermogravimetry/differential scanning calorimetry (TG/DSC. The introduction of the template could improve the monomer (AATPAC reactivity ratio and increase the length and amount of AATPAC segments. This novel cationic microblock structure extremely enhanced the ability of charge neutralization, patching, and bridging, thus improving the activated sludge flocculation performance. The experiments of floc formation, breakage, and regrowth revealed that the cationic microblock structure in the copolymer resulted in large and compact flocs, and these flocs had a rapid regrowth when broken. Finally, the larger and more compact flocs contributed to the formation of more channels and voids, and therefore the specific resistance to filtration (SRF reached a minimum.

  7. Studies on compatibility of energetic materials by thermal methods

    Directory of Open Access Journals (Sweden)

    Maria Alice Carvalho Mazzeu

    2010-04-01

    Full Text Available The chemical compatibility of explosives, pyrotechnics and propellants with those materials is studied to evaluate potential hazards when in contact with other materials during production, storage and handling. Compatibility can be studied by several thermal methods as DSC (differential scanning calorimetry, TG (Thermogravimetry, VST (Vacuum stability test and others. The test methods and well defined criteria are the most important elements when a compatibility study is being accomplished. In this paper, the compatibility of two very important high explosives used in ammunition, RDX (Cyclo-1,3,5-trimethylene-2,4,6-trinitramine and HMX (Cyclotetramethylene tetranitramine was studied with the materials: fluoroelastomer (Viton and powdered aluminum (Al, using DSC and VST methods. The criteria to judge the compatibility between materials is based on a standardization agreement (STANAG 4147, 2001, and the final conclusion is that explosives and this materials are compatible, but in DSC it was observed that the peak of decomposition temperature of the admixture of RDX with Al decreased in 3º C and another peak appeared after the decomposition peak.

  8. A simple large-scale synthesis of mesoporous In2O3 for gas sensing applications

    Science.gov (United States)

    Zhang, Su; Song, Peng; Yan, Huihui; Yang, Zhongxi; Wang, Qi

    2016-08-01

    In this paper, large-scale mesoporous In2O3 nanostructures were synthesized by a facile Lewis acid catalytic the furfural alcohol resin (FAR) template route for the high-yield. Their morphology and structure were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential thermal and thermogravimetry analysis (DSC-TG) and the Brunauer-Emmett-Teller (BET) approach. The as-obtained mesoporous In2O3 nanostructures possess excellent mesoporous and network structure, which increases the contact area with the gases, it is conducive for adsorption-desorption of gas on the surface of In2O3. The In2O3 particles and pores were both about 15 nm and very uniform. In gas-sensing measurements with target gases, the gas sensor based on mesoporous In2O3 nanostructures showed a good response, short response-recovery time, good selectivity and stability to ethanol. These properties are due to the large specific surface area of mesoporous structure. This synthetic method could use as a new design concept for functional mesoporous nanomaterials and for mass production.

  9. Febuxostat-Minoxidil Salt Solvates: Crystal Structures, Characterization, Interconversion and Solubility Performance

    Directory of Open Access Journals (Sweden)

    Li-Yang Li

    2018-02-01

    Full Text Available Three febuxostat-minoxidil salt solvates with acetone (ACE, tetrahydrofuran (THF and isopropanol (IPA are synthesized by solvent-assisted grinding and characterized by infrared (IR, nuclear magnetic resonance (1H-NMR, single crystal and powder X-ray diffraction (PXRD, thermogravimetry (TG and differential scanning calorimetry (DSC. These febuxostat-minoxidil salt solvates feature isostructural with the same stoichiometries (1:1:1 molecule ratio. The proton transfers from the carboxylic group of febuxostat (FEB to imino N atom of minoxidil (MIN, which forms the motif with combined R 2 2 (9 R 4 2 (8 R 2 2 (9 graph set in the three solvates. The solvents occupy the different positions related to the motif, which results in the apparent differences in PXRD patterns before/after desolvation although they are isostructures. The FEB-MIN·THF was more thermostable than FEB-MIN·ACE and FEB-MIN·IPA relative to solvent removal from DSC patterns, which is different from the results from the solvent-exchange experiments in chemical kinetics. All three salt solvates exhibit increased equilibrium solubility compared to FEB in aqueous medium.

  10. Synthesis and characterization of a layered double hydroxide containing an intercalated nickel(II) citrate complex

    International Nuclear Information System (INIS)

    Wang Lianying; Wu Guoqing; Evans, David G.

    2007-01-01

    The nickel(II) citrate complex anion ([Ni(C 6 H 4 O 7 )] 2- ) may be intercalated into the interlayer galleries of a layered double hydroxide (LDH) host by a process involving ion-exchange with an Mg 2 Al-NO 3 LDH precursor. The powder X-ray diffraction (XRD) pattern confirms that the layered structure is maintained. The thermal decomposition process of the complex anion-intercalated material has been characterized by in situ high temperature powder XRD, thermogravimetry-differential thermal analysis (TG-DTA) and coupled with mass spectrometry (MS). The thermal stability of the nickel(II) citrate complex anion intercalated in LDHs in air is lower than that in the sodium salt. Calcination generates a high degree of nickel(II) oxide dispersion in a matrix of magnesium and aluminium oxide phases which should be an advantage if the materials are used as catalyst precursors. Based on the observed data, a structural model for the [Ni(C 6 H 4 O 7 )] 2- anion intercalated in the galleries of the LDH is proposed

  11. Development of a reconversion method for uranyl nitrate to oxide in the reconversion step of reprocessing of irradiated fuel

    International Nuclear Information System (INIS)

    Govindan, P.; Palamalai, A.; Vijayan, K.S.; Subbuthai, S.; Murugesan, S.; Mohan, S.V.; Subba Rao, R.V.

    2002-01-01

    Ammonium uranyl carbonate (AUC) precipitation is developed for the conversion of uranyl nitrate to oxide in the uranium reconversion step of reprocessing of irradiated fuel by the addition of ammonium carbonate salt. Different precipitation conditions of AUC are studied. The solubility of AUC as a function of uranium concentration in the feed at different temperatures using ammonium carbonate salt as precipitant is studied. This study indicates that 95-99.8% of uranium is recovered as AUC by precipitating 5-125 g/l of uranium with loss of uranium (250-10 ppm) in the filtrate by adding ammonium carbonate salt. It is also observed that the solubility of AUC increased as the concentration of uranium decreased. Thermal decomposition is carried out by thermogravimetry/differential thermal analysis (TG/DTA) and evolved gas analysis-mass spectrometry (EGA-MS) to find out AUC decomposition and gases evolved during decomposition. Studies are also carried out to characterize AUC by using X-ray diffraction (XRD). The data show that AUC obtained by the above conditions is very much consistent with published information. (author)

  12. Stabilization/solidification of sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Boura, Panagiota; Katsioti, Margarita; Tsakiridis, Petros; Katsiri, Alexandra

    2003-07-01

    The main objective of this work is to investigate a viable alternative for the final disposal of sewage sludge from urban wastewater treatment plants by its use as an additive in developing new construction materials. For this purpose, several mixtures of sludge- cement and sludge-cement and jarosite/alunite precipitate were prepared. Jarosite/alunite precipitate is a waste product of a new hydrometallurgical process. Two kinds of sludge were used: primary sludge from Psyttalia Wastewater Treatment Plant, which receives a considerable amount of industrial waste, and biological sludge from Metamorphosi Wastewater Treatment Plant. Various percentages of these sludges were stabilized/solidified with Portland cement and Portland cement with jarosite/alunite. The specimens were tested by determination of compressive strength according to the methods described by European Standard EN 196. X-Ray Diffraction (XRD) analysis as well as Thermogravimetry-Differential Thermal Analysis (TG-DTA) were used to determine the hydration products in 28 days. Furthermore, Toxicity Characteristic Leaching Procedure test for heavy metals (TCLP), were carried out in order to investigate the environmental compatibility of these new materials. (author)

  13. Following-up the efficiency of 131-Iodine therapy in differentiated thyroid carcinoma (excluding medullary) - Moroccan situation

    International Nuclear Information System (INIS)

    Ben Rais Aouad, N.

    2004-01-01

    Full text: Since 1985, the department of nuclear medicine of IBN SINA Hospital in the Rabat University hospital centre is the only centre in Morocco, where all patients of differentiated thyroid carcinoma after surgery are treated with 3.7 GBq of Iodine-131. The number of patients on follow-up is more than two thousands. The endemic zone represents the main origin of thyroid carcinoma. The sex ratio (F/M) is 3.5/1; the mean age is 42.5 years. The papillary carcinoma constitutes about 65.5% of the 26% of well-differentiated carcinoma and 12.5 of moderately differentiated carcinoma (MDC). The tumour size at diagnosis was more than 2 cm in 70% of cases. Prognosis factors are the age, the histology and tumour size. After the surgery, the patients receive 131-Iodine therapy (3.7 GBq) and a regular follow-up by clinical examination, neck ultrasonography and thyroglobulin (Tg) blood level. The aim is to obtain a negative whole body scan (WBS) and undetectable Tg. All the patients also receive a suppressive hormone therapy (thyroxin: 2.4 μg/kg/day). In the same patient, the Tg level is also compared with and without suppression therapy, but taking TSH levels into account. The efficiency of 131-Iodine treatment and the following up, depends on the type of patients: (a) Patients without metastasis: the success of Iodine-131 therapy depended on surgery and it was more than 92% (b) Patients with local metastasis to lymph nodes: the success of 131-Iodine therapy depended of nodal status and complete dissection is possible in 70% cases only. (c) Patients with distant metastasis: The efficiency of 131-Iodine therapy depended on the uptake, the homogeneity and the size of metastasis. In lung metastasis, the efficiency of 131-Iodine is about 40-42% (70%: miliary and micro nodules) and only 6.6% in bone metastasis. After treatment, the patients were regularly followed-up clinically till the next WBS and Tg estimation. In some cases, it was interesting to compare WBS and MIBI

  14. Anxiety-like behavior as an early endophenotype in the TgF344-AD rat model of Alzheimer's disease.

    Science.gov (United States)

    Pentkowski, Nathan S; Berkowitz, Laura E; Thompson, Shannon M; Drake, Emma N; Olguin, Carlos R; Clark, Benjamin J

    2018-01-01

    Alzheimer's disease (AD) is characterized by progressive cognitive decline and the presence of aggregates of amyloid beta (plaques) and hyperphosphorylated tau (tangles). Early diagnosis through neuropsychological testing is difficult due to comorbidity of symptoms between AD and other types of dementia. As a result, there is a need to identify the range of behavioral phenotypes expressed in AD. In the present study, we utilized a transgenic rat (TgF344-AD) model that bears the mutated amyloid precursor protein as well as presenilin-1 genes, resulting in progressive plaque and tangle pathogenesis throughout the cortex. We tested young adult male and female TgF344-AD rats in a spatial memory task in the Morris water maze and for anxiety-like behavior in the elevated plus-maze. Results indicated that regardless of sex, TgF344-AD rats exhibited increased anxiety-like behavior in the elevated plus-maze, which occurred without significant deficits in the spatial memory. Together, these results indicate that enhanced anxiety-like behavior represents an early-stage behavioral marker in the TgF344-AD rat model. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Ocular Changes in TgF344-AD Rat Model of Alzheimer's Disease

    OpenAIRE

    Tsai, Yuchun; Lu, Bin; Ljubimov, Alexander V.; Girman, Sergey; Ross-Cisneros, Fred N.; Sadun, Alfredo A.; Svendsen, Clive N.; Cohen, Robert M.; Wang, Shaomei

    2014-01-01

    In this study, we observed pathological changes in the choroid and in RPE cells in the TgF344-AD rat model; choroidal thinning was further observed in human AD retina. Along with Aβ deposition, the inflammatory response was manifested by microglial recruitment and complement activation.

  16. Determination of Therapeutic Dose of I-131 for First High Dose Radioiodine Therapy in Patients with Differentiated Thyroid Cancer: Comparison of Usefulness between Pathological Staging, Serum Thyroglobulin Level and Finding of I-123 Whole Body Scan

    International Nuclear Information System (INIS)

    Jeong, Hwan Jeong; Lim, Seok Tae; Youn, Hyun Jo; Sohn, Myung-Hee

    2008-01-01

    Recently, a number of patients needed total thyroidectomy and high dose radioiodine therapy (HD-RAI) get increased more. The aim of this study is to evaluate whether pathological staging (PS) and serum thyroglobulin (sTG) level could replace the diagnostic I-123 scan for the determination of therapeutic dose of HD-RAI in patients with differentiated thyroid cancer. Fifty eight patients (M:F=13;45, age 44.5±11.5 yrs) who underwent total thyroidectomy and central or regional lymph node dissection due to differentiated thyroid cancer were enrolled. Diagnostic scan of I-123 and sTG assay were also performed on off state of thyroid hormone. The therapeutic doses of I-131 (TD) were determined by the extent of uptakes on diagnostic I-123 scan as a gold standard. PS was graded by the criteria recommended in 6th edition of AJCC cancer staging manual except consideration of age. For comparison of the determination of therapeutic doses, PS and sTG were compared with the results of I-123 scan. All patients were underwent HD-RAI. Among them, five patients (8.6%) were treated with 100 mCi of I-131, forty three (74.1%) with 150 mCi, six (10.3%) with 180 mCi, three (5.2%) with 200 mCi, and one (1.7%) with 250 mCi, respectively. On the assessment of PS, average TDs were 154±25 mCi in stage I (n=9), 175±50 mCi in stage II (n=4), 149±21 mCi in stage III (n=38), and 161±20 mCi in stage IV (n=7). The statistical significance was not shown between PS and TD (p=0.169). Among fifty two patients who had available sTG, 25 patients (48.1%) having below 2 ng/mL of sTG were treated with 149±26 mCi of I-131, 9 patients (17.3%) having 2≤ sTG <5 ng/mL with 156±17 mCi, 5 patients (9.6%) having 5≤ sTG <10 ng/mL with 156±13 mCi, 7 patients (13.5%) having 10≤ sTG <50 ng/mL with 147±24 mCi, and 6 patients (11.5%) having above 50 ng/mL with 175±42 mCi. The statistical significance between sTG level and TD (p=0.252) was not shown. In conclusion, PS and sTG could not replace the

  17. TU-E-BRB-03: Overview of Proposed TG-132 Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Brock, K. [University of Michigan (United States)

    2015-06-15

    Deformable image registration (DIR) is developing rapidly and is poised to substantially improve dose fusion accuracy for adaptive and retreatment planning and motion management and PET fusion to enhance contour delineation for treatment planning. However, DIR dose warping accuracy is difficult to quantify, in general, and particularly difficult to do so on a patient-specific basis. As clinical DIR options become more widely available, there is an increased need to understand the implications of incorporating DIR into clinical workflow. Several groups have assessed DIR accuracy in clinically relevant scenarios, but no comprehensive review material is yet available. This session will also discuss aspects of the AAPM Task Group 132 on the Use of Image Registration and Data Fusion Algorithms and Techniques in Radiotherapy Treatment Planning official report, which provides recommendations for DIR clinical use. We will summarize and compare various commercial DIR software options, outline successful clinical techniques, show specific examples with discussion of appropriate and inappropriate applications of DIR, discuss the clinical implications of DIR, provide an overview of current DIR error analysis research, review QA options and research phantom development and present TG-132 recommendations. Learning Objectives: Compare/contrast commercial DIR software and QA options Overview clinical DIR workflow for retreatment To understand uncertainties introduced by DIR Review TG-132 proposed recommendations.

  18. Cotinine halts the advance of Alzheimer’s disease-like pathology and associated depressive-like behavior in Tg6799 mice

    Directory of Open Access Journals (Sweden)

    Sagar ePatel

    2014-07-01

    Full Text Available Alzheimer’s disease (AD is associated with cognitive and non-cognitive symptoms for which there are currently no effective therapies. We have previously reported that cotinine, a natural product obtained from tobacco leaves, prevented memory loss and diminished amyloid-β (Aβ plaque pathology in the transgenic 6799 mice (Tg6799 mice when treated prior to the development of the pathology. We have also shown that cotinine reduces depressive-like behavior in normal and chronically stressed C57BL/6 mice. Here, we extend our previous studies by investigating the effects of cotinine on the progression of AD-like pathology, depressive-like behavior, and the mechanisms underlying its beneficial effects in the Tg6799 mice when left untreated until after a more advanced stage of the disease’s development. The results show that vehicle-treated Tg6799 mice displayed an accentuated loss of working memory and an abundant Aβ plaque pathology that were accompanied by higher levels of depressive-like behavior as compared to control littermates. By contrast, prolonged daily cotinine treatment, withheld until after a mid-level progression of AD-like pathology, reduced Aβ levels, Aβ plaques, and depressive-like behavior as well as dramatically improved working memory in Tg6799 mice to levels no different from control littermates. The beneficial effects of cotinine were accompanied by an increase in the expression of the active form of protein kinase B (Akt and the postsynaptic density protein 95 (PSD95 in the hippocampi and frontal cortices of Tg6799 mice. This suggests that cotinine halts the progression of AD-like pathology while reducing depressive-like behavior by stimulating signaling pathways supporting synaptic plasticity in Tg6799 mice. The potential use of cotinine to treat cognitive and non-cognitive symptoms of AD is discussed.

  19. Toxoplasma gondii: humoral and cellular immune response of BALB/c mice immunized via intranasal route with rTgROP2 Toxoplasma gondii: avaliação da resposta imune humoral e celular de camundongos BALB/c imunizados pela via nasal com rTgROP2

    Directory of Open Access Journals (Sweden)

    Michelle Igarashi

    2010-12-01

    Full Text Available TgROP2 is an intracellular protein associated with rhoptries of Toxoplama gondii and an antigen component of a candidate vaccine for toxoplasmosis. The purpose of the present study was to evaluate the efficacy of rTgROP2 to stimulate humoral and cellular immune responses in BALB/c mice via intranasal injection. TgROP2 partial coding sequence was (196-561 amplified by PCR from genomic T. gondii RH strain DNA and cloned into the pTrcHis expression vector. Escherichia coli Rosetta 2 cells transformed with pTrcHis-TgROP2 showed high levels (~1 mg.mL-1 of recombinant protein after 4 hours of IPTG induction. Recombinant TgROP2 exhibited an apparent Mr equal to 54 kDa. In order to test immunogenicity of the recombinant protein, 10 BALB/c mice received 10 µg of rROP2 protein + 10 µg of Quil-A via intranasal injection. Doses were administered at days 0, 21, and 42. Three animals were euthanized and used to evaluate cell-ular immune response on day 62. Five (50% and two (20% out of ten animals produced IgG (DO mean = 0.307; cut-off = 0.240 and IgA (DO mean = 0.133, cut-off = 0.101, respectively, by ELISA on day 62. The proliferation of splenocytes revealed high stimulation index (SI when co-cultured with 5, 10 and 15 µg.mL-1 of rTgROP2. These results indicate that intranasal immunization with recombinant protein ROP2 plus Quil-A can elicit both cellular and humoral immune responses in BALB/c mice.TgROP2 é uma proteína localizada nas roptrias do Toxoplasma gondii, sendo um antígeno candidato a componente de uma vacina contra a toxoplasmose. O objetivo do presente estudo foi avaliar a eficácia da TgROP2 recombinante em estimular a resposta imune celular e humoral de camundongos BALB/c após estímulo intranasal. A sequência da TgROP2 foi amplificada pela PCR a partir da cepa RH e clonada em vetor de expressão pTrc-His. Após a transformação em Escherichia coli- Rosetta 2, a pTrcHis-TgROP2 exibiu alto nível de expressão após 4 horas de indu

  20. SU-E-J-52: Decreasing Frequency of Performing TG-142 Imaging QA – 5 Year Experience

    International Nuclear Information System (INIS)

    Lin, T; Ma, C

    2015-01-01

    Purpose This study is an update to check if the frequency of imaging QA suggested by AAPM Task Group Report 142 (TG142) is necessary with our 5 year experience. TG142 presents recommendations for QA criteria of IGRT treatment. ACR has adopted it to be the requirements for any radiatiotherapy practices; however, we propose to reduce the frequency on image quality QA according to this 5 year study.Method and Materials: This study uses VarianIX2100 and Siemens Artiste Linacs to perform QAs on KV, MV, CBCT modalities. The QA was designed following under the recommendations of TG142. This study reports the daily imaging positioning/repositioning and imaging and treatment coordinate coincidence. QA results on kV, MV and CBCT from 4/7/2010∼3/11/15 are analyzed. KV, MV, CBCT images are taken with the Varian isocube localized at the isocenter. Digital graticule is used in the software to verify the isocenter position. CBCT images are taken with the cube placed at 1cm superior, lateral and anterior of the isocenter. In-line fusion software is used to verify the contrived shift. Digital ruler provided at the on-board-imaging software or adaptive-targeting software was used to measure the position differences. The position differences were recorded at AP,LR,SI directions. Results 5 year records on kV, MV, CBCT show the shifts in all three directions are within the tolerance of 1mm suggested in TG142 for stereotactic radiation treatment(SRS/SRT). There is no occasion where shifts are outside 1mm tolerance. Conclusions The daily imaging QA suggested in TG142 is useful in ensuring the accuracy needed for SRS/SRT in IGRT. 5 year measurements presented suggest that decreasing the frequency of imaging QA may be acceptable, in particular for institutions reporting no violation of tolerance over periods of few years

  1. SU-E-J-52: Decreasing Frequency of Performing TG-142 Imaging QA – 5 Year Experience

    Energy Technology Data Exchange (ETDEWEB)

    Lin, T; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States)

    2015-06-15

    Purpose This study is an update to check if the frequency of imaging QA suggested by AAPM Task Group Report 142 (TG142) is necessary with our 5 year experience. TG142 presents recommendations for QA criteria of IGRT treatment. ACR has adopted it to be the requirements for any radiatiotherapy practices; however, we propose to reduce the frequency on image quality QA according to this 5 year study.Method and Materials: This study uses VarianIX2100 and Siemens Artiste Linacs to perform QAs on KV, MV, CBCT modalities. The QA was designed following under the recommendations of TG142. This study reports the daily imaging positioning/repositioning and imaging and treatment coordinate coincidence. QA results on kV, MV and CBCT from 4/7/2010∼3/11/15 are analyzed. KV, MV, CBCT images are taken with the Varian isocube localized at the isocenter. Digital graticule is used in the software to verify the isocenter position. CBCT images are taken with the cube placed at 1cm superior, lateral and anterior of the isocenter. In-line fusion software is used to verify the contrived shift. Digital ruler provided at the on-board-imaging software or adaptive-targeting software was used to measure the position differences. The position differences were recorded at AP,LR,SI directions. Results 5 year records on kV, MV, CBCT show the shifts in all three directions are within the tolerance of 1mm suggested in TG142 for stereotactic radiation treatment(SRS/SRT). There is no occasion where shifts are outside 1mm tolerance. Conclusions The daily imaging QA suggested in TG142 is useful in ensuring the accuracy needed for SRS/SRT in IGRT. 5 year measurements presented suggest that decreasing the frequency of imaging QA may be acceptable, in particular for institutions reporting no violation of tolerance over periods of few years.

  2. Body weight - Open TG-GATEs | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...le URL: ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/open_tggates_body_...atabase Description Download License Update History of This Database Site Policy | Contact Us Body weight - Open TG-GATEs | LSDB Archive ...

  3. Investigation on thermophysical properties of RE{sub 6}UO{sub 12}(s) (RE = La, Pr, Nd, Sm)

    Energy Technology Data Exchange (ETDEWEB)

    Sahu, Manjulata, E-mail: manju@barc.gov.in [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Krishnan, K. [Fuel Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Jain, Dheeraj [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Saxena, M.K. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Dash, Smruti [Product development Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2016-08-10

    Highlights: • Synthesis of RE{sub 6}UO{sub 12}(s)(RE = La, Pr, Nd, Sm) was performed by combustion method and characterization by XRD. • Thermal expansion measurements were carried out on RE{sub 6}UO{sub 12}(s)(RE = Pr, and Sm) using HT-XRD. • Heat capacity of RE{sub 6}UO{sub 12}(s)(RE = La, Pr, Nd, Sm) was measured in the temperature range 300–870 K. • The nonstoichiometry in RE{sub 6}UO{sub 12}(s) was checked using TG, XPS, chemical analysis and electrical conductivity measurement. - Abstract: RE{sub 6}UO{sub 12}(s) (RE = La, Pr, Nd, Sm) was synthesized by citrate-nitrate combustion method. The synthesis condition for Pr{sub 6}UO{sub 12}(s) was optimized. Nonstoichiometry in these rare earth uranates in argon atmosphere was analysed using various techniques like thermogravimetry (TG), X-ray photo electron spectroscopy (XPS), chemical analysis and electrical conductivity measurements. Thermal expansions of RE{sub 6}UO{sub 12}(s) (RE = Pr and Sm) was studied in the temperature range 298–1273 K by high temperature X-ray powder diffractometry and compared with that of similar rare earth compounds reported in the literature. Heat capacity of RE{sub 6}UO{sub 12}(s) (RE = La, Pr, Nd, Sm) was measured by differential scanning calorimetry in the temperature range 300–870 K. Enthalpy, entropy and Gibbs energy functions of these compounds were computed from the measured heat capacity data.

  4. Pyrolysis characteristics and kinetics of oil-based drilling cuttings in shale gas developing

    Science.gov (United States)

    Huang, Chuan; Li, Tong; Xu, Tengtun; Zeng, Yunmin; Song, Xue

    2018-03-01

    In this paper, the thermal behavior of waste oil-based drilling cuttings (from shale gas fields in Chongqing) was examined at different heating rates ranging from 5 to 15 °C min-1 in inert atmosphere using a sync analyzer of thermogravimetry (TG) and differential scanning calorimetry (DSC). Four methods were used to analyze the distributions and variations of kinetics parameter (active energy (E) and frequency gene (A)): Coats-Redfern and other three iso-conversion rate methods (Flynn-Wall-Ozawa, Vyazovkin and Friedman). The experimental results indicated that the process consists of three steps, i.e., water evaporation, volatilization of light oil component and heavy oil cracking. TG curves moved toward higher temperature zone caused by thermal hysteresis with the increase of temperature rising rate. For volatilization of lightweight components, the E calculated by three iso-conversion rate methods changed a little with conversion, and had almost the same results as the CR method (14.39˜20.08 kJ.mol-1). For reactions of heavy oil cracking with mixed mechanism, corresponding E rose gradually with the increase of reaction time. The CR method shows nonlinear trends and the reaction models and kinetic parameters cannot be extracted from CR curves. The results by three iso-conversion methods showed that apparent activation energy was given as 155.74˜561.10 kJ.mol-1, 141.06˜524.96 kJ.mol-1 and 74.37˜605.10 kJ.mol-1, respectively.

  5. Poly(vinylidene fluoride) modification induced by gamma irradiation for application as ionic polymer-metal composite; Modificacao de poli(fluoreto de vinilideno) induzida por radiacao gama para aplicacao como composito ionomerico de metal-polimero

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Henrique Perez

    2011-07-01

    Gamma-radiation-induced grafting of styrene into poly(vinylidene fluoride) (PVDF) films with 0.125 mm thickness at doses from 1 to 100 kGy in the presence of a styrene/N,N- dimethylformamide (DMF) solution (1:1, v/v) and styrene/toluene (1:1, v/v) at dose rate of 5 kGy h-1 was carried out by simultaneous method under nitrogen atmosphere at room temperature, using gamma rays from a Co-60. After grafting reactions, the polymer was then sulfonated in chlorosulfonic acid/1,2-dichloroethane (2 and 10%) for 3 hours. The films were characterized before and after modification by calculating the degree of grafting (DOG), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). DOG results show that grafting increases with dose, and varies enormously depending on the solvent used, with DOGs about 20 times greater in DMF than in toluene. It was possible to confirm the grafting of styrene by FT-IR due to the appearance of the new characteristic peaks and by the TG and DSC which exhibited changes in the thermal behavior of the grafted/sulfonated material. Sulfonated material was also characterized by ion exchange capacity (IEC) showed that both DOG and sulfonic acid concentration increase IEC values. Results showed that it is possible to obtain materials with ion exchange capacity of possible application as ionic polymer-metal composites. (author)

  6. Organotin(IV complexes derived from N-ethyl-N-phenyldithiocarbamate: Synthesis, characterization and thermal studies

    Directory of Open Access Journals (Sweden)

    Jerry O. Adeyemi

    2018-05-01

    Full Text Available Organotin(IV dithiocarbamate complexes, RSnClL2 and R2SnL2 (R = Me, Bu, Ph, and L = N-ethyl-N-phenyldithiocarbamate, have been synthesized by the reaction of mono- and disubstituted organotin(IV with ammonium dithiocarbamate. The complexes were characterized by elemental analyses, and spectroscopic techniques (1H, 13C NMR and FTIR. The structures of Me2SnL2 and Bu2SnL2 were further established by single crystal X-ray diffraction technique. The crystal structure analysis showed that both complexes (Me2SnL2 and Bu2SnL2 exist as monomers. One of the dithiocarbamate ligands formed a chelate, while the other dithiocarbamate bonded to the central tin atom through one of the sulfur atoms and the second sulfur atom existed as a pendant to form distorted trigonal bipyramidal geometry. The thermal stability of all the complexes was studied using simultaneous thermogravimetry (TG and differential scanning calorimetry (DSC. The TG-DSC results showed that Me2SnL2, BuSnClL2, Bu2SnL2, and PhSnClL2 displayed similar decomposition pathway via isothiocyanate intermediate, while MeSnClL2 and Ph2SnL2 showed decomposition pathways different from the rest of the complexes. All the complexes resulted in SnS as the final product of the thermal decomposition process. Keywords: Organotin, Dithiocarbamate, Crystal structure, Thermal studies

  7. Poly(vinylidene fluoride) modification induced by gamma irradiation for application as ionic polymer-metal composite

    International Nuclear Information System (INIS)

    Ferreira, Henrique Perez

    2011-01-01

    Gamma-radiation-induced grafting of styrene into poly(vinylidene fluoride) (PVDF) films with 0.125 mm thickness at doses from 1 to 100 kGy in the presence of a styrene/N,N- dimethylformamide (DMF) solution (1:1, v/v) and styrene/toluene (1:1, v/v) at dose rate of 5 kGy h-1 was carried out by simultaneous method under nitrogen atmosphere at room temperature, using gamma rays from a Co-60. After grafting reactions, the polymer was then sulfonated in chlorosulfonic acid/1,2-dichloroethane (2 and 10%) for 3 hours. The films were characterized before and after modification by calculating the degree of grafting (DOG), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). DOG results show that grafting increases with dose, and varies enormously depending on the solvent used, with DOGs about 20 times greater in DMF than in toluene. It was possible to confirm the grafting of styrene by FT-IR due to the appearance of the new characteristic peaks and by the TG and DSC which exhibited changes in the thermal behavior of the grafted/sulfonated material. Sulfonated material was also characterized by ion exchange capacity (IEC) showed that both DOG and sulfonic acid concentration increase IEC values. Results showed that it is possible to obtain materials with ion exchange capacity of possible application as ionic polymer-metal composites. (author)

  8. Statistical optimization of microencapsulation process for coating of magnesium particles with Viton polymer

    Energy Technology Data Exchange (ETDEWEB)

    Pourmortazavi, Seied Mahdi, E-mail: pourmortazavi@yahoo.com [Faculty of Material and Manufacturing Technologies, Malek Ashtar University of Technology, P.O. Box 16765-3454, Tehran (Iran, Islamic Republic of); Babaee, Saeed; Ashtiani, Fatemeh Shamsi [Faculty of Chemistry & Chemical Engineering, Malek Ashtar University of Technology, Tehran (Iran, Islamic Republic of)

    2015-09-15

    Graphical abstract: - Highlights: • Surface of magnesium particles was modified with Viton via solvent/non-solvent method. • FT-IR, SEM, EDX, Map analysis, and TG/DSC techniques were employed to characterize the coated particles. • Coating process factors were optimized by Taguchi robust design. • The importance of coating conditions on resistance of coated magnesium against oxidation was studied. - Abstract: The surface of magnesium particles was modified by coating with Viton as an energetic polymer using solvent/non-solvent technique. Taguchi robust method was utilized as a statistical experiment design to evaluate the role of coating process parameters. The coated magnesium particles were characterized by various techniques, i.e., Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and thermogravimetry (TG), and differential scanning calorimetry (DSC). The results showed that the coating of magnesium powder with the Viton leads to a higher resistance of metal against oxidation in the presence of air atmosphere. Meanwhile, tuning of the coating process parameters (i.e., percent of Viton, flow rate of non-solvent addition, and type of solvent) influences on the resistance of the metal particles against thermal oxidation. Coating of magnesium particles yields Viton coated particles with higher thermal stability (632 °C); in comparison with the pure magnesium powder, which commences oxidation in the presence of air atmosphere at a lower temperature of 260 °C.

  9. Facile Preparation of Phosphotungstic Acid-Impregnated Yeast Hybrid Microspheres and Their Photocatalytic Performance for Decolorization of Azo Dye

    Directory of Open Access Journals (Sweden)

    Lan Chen

    2013-01-01

    Full Text Available Phosphotungstic acid (HPW-impregnated yeast hybrid microspheres were prepared by impregnation-adsorption technique through tuning pH of the aqueous yeast suspensions. The obtained products were characterized by field emission scanning electron microscopy (FE-SEM, energy dispersive spectrometry (EDS, X-ray diffraction (XRD, thermogravimetry-differential scanning calorimetry (TG-DSC, and ultraviolet-visible spectrophotometry (UV-Vis, respectively. FE-SEM and EDS ascertain that the HPW has been effectively introduced onto the surface of yeast, and the resulting samples retain ellipsoid shape, with the uniform size (length 4.5 ± 0.2 μm, width 3.0 ± 0.3 μm and good monodispersion. XRD pattern indicates that the main crystal structure of as-synthesized HPW@yeast microsphere is Keggin structure. TG-DTA states that the HPW in composites has better thermal stability than pure HPW. Fourier transform infrared spectroscopy (FT-IR elucidates that the functional groups or chemical bonds inherited from the pristine yeast cell were critical to the assembling of the composites. UV-Vis shows that the obtained samples have a good responding to UV light. The settling ability indicates that the hybrid microspheres possess an excellent suspension performance. In the test of catalytic activity, the HPW@yeast microsphere exhibits a high photocatalytic activity for the decoloration of Methylene blue and Congo red dye aqueous solutions, and there are a few activity losses after four cycles of uses.

  10. Synthesis of Non-Toxic Silica Particles Stabilized by Molecular Complex Oleic-Acid/Sodium Oleate

    Directory of Open Access Journals (Sweden)

    Catalin Ilie Spataru

    2016-11-01

    Full Text Available The present work is focused on the preparation of biocompatible silica particles from sodium silicate, stabilized by a vesicular system containing oleic acid (OLA and its alkaline salt (OLANa. Silica nanoparticles were generated by the partial neutralization of oleic acid (OLA, with the sodium cation present in the aqueous solutions of sodium silicate. At the molar ratio OLA/Na+ = 2:1, the molar ratio (OLA/OLANa = 1:1 required to form vesicles, in which the carboxyl and carboxylate groups have equal concentrations, was achieved. In order to obtain hydrophobically modified silica particles, octadecyltriethoxysilane (ODTES was added in a sodium silicate sol–gel mixture at different molar ratios. The interactions between the octadecyl groups from the modified silica and the oleyl chains from the OLA/OLANa stabilizing system were investigated via simultaneous thermogravimetry (TG and differential scanning calorimetry (DSC (TG-DSC analyses.A significant decrease in vaporization enthalpy and an increase in amount of ODTES were observed. Additionally, that the hydrophobic interaction between OLA and ODTES has a strong impact on the hybrids’ final morphology and on their textural characteristics was revealed. The highest hydrodynamic average diameter and the most negative ζ potential were recorded for the hybrid in which the ODTES/sodium silicate molar ratio was 1:5. The obtained mesoporous silica particles, stabilized by the OLA/OLANa vesicular system, may find application as carriers for hydrophobic bioactive molecules.

  11. Preliminary characterization in the development of the nano composite low density polyethylene with attapulgite clay

    International Nuclear Information System (INIS)

    Domingos, Luanda G.; Rego, Jose K.M.A. do; Ito, Edson N.; Acchar, Wilson

    2011-01-01

    The aim of this study was a preliminary study of the physical, thermal and rheological properties of the materials to be used in the development of nano composite low density polyethylene (LDPE) with Brazilian attapulgite clay (ATP), with and without the use of a compatibilizing agent interfacial, polyethylene grafted with maleic anhydride (PE-g-MAH). The materials were characterized by X-ray diffraction (XRD), thermogravimetry (TG) and torque rheometry. The materials were characterized and potentially could be developed polymeric nano composites with technological applications using attapulgite fibers in the nanometer scale. (author)

  12. A vacuolar iron transporter in tulip, TgVit1, is responsible for blue coloration in petal cells through iron accumulation.

    Science.gov (United States)

    Momonoi, Kazumi; Yoshida, Kumi; Mano, Shoji; Takahashi, Hideyuki; Nakamori, Chihiro; Shoji, Kazuaki; Nitta, Akira; Nishimura, Mikio

    2009-08-01

    Blue color in flowers is due mainly to anthocyanins, and a considerable part of blue coloration can be attributed to metal-complexed anthocyanins. However, the mechanism of metal ion transport into vacuoles and subsequent flower color development has yet to be fully explored. Previously, we studied the mechanism of blue color development specifically at the bottom of the inner perianth in purple tulip petals of Tulipa gesneriana cv. Murasakizuisho. We found that differences in iron content were associated with the development of blue- and purple-colored cells. Here, we identify a vacuolar iron transporter in T. gesneriana (TgVit1), and characterize the localization and function of this transporter protein in tulip petals. The amino acid sequence of TgVit1 is 85% similar that of the Arabidopsis thaliana vacuolar iron transporter AtVIT1, and also showed similarity to the AtVIT1 homolog in yeast, Ca(2+)-sensitive cross-complementer 1 (CCC1). The gene TgVit1 was expressed exclusively in blue-colored epidermal cells, and protein levels increased with increasing mRNA expression and blue coloration. Transient expression experiments revealed that TgVit1 localizes to the vacuolar membrane, and is responsible for the development of the blue color in purple cells. Expression of TgVit1 in yeast rescued the growth defect of ccc1 mutant cells in the presence of high concentrations of FeSO(4). Our results indicate that TgVit1 plays an essential role in blue coloration as a vacuolar iron transporter in tulip petals. These results suggest a new role for involvement of a vacuolar iron transporter in blue flower color development.

  13. Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Lin Jen-Der; Weng Hsiao-Fen; Lu Wen-Tsoung [Division of Endocrinology and Metabolism, Chang Gung Memorial Hospital (Taiwan, Province of China); Kao Pan-Fu; Huang Miau-Ju [Department of Nuclear Medicine, Chang Gung Memorial Hospital, Taiwan (Taiwan, Province of China)

    1998-07-01

    Radioactive iodine ({sup 131}I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. {sup 201}Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative {sup 131}I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of {sup 201}Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of {sup 131}I and {sup 201}Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative {sup 201}Tl and {sup 131}I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. {sup 201}Tl imaging was performed before the {sup 131}I studies. Of the 62 patients who underwent {sup 201}Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the {sup 201}Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic {sup 131}I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by {sup 201}Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative {sup 201}Tl scans, 11 had positive findings on {sup 131}I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on {sup 131}I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative {sup 201}Tl and {sup 131}I

  14. The study of forms of bonding marshmallow moisture with different composition by method of thermal analysis

    Directory of Open Access Journals (Sweden)

    G. O. Magomedov

    2017-01-01

    Full Text Available Marshmallow is a sugar confectionary product with increased sugar content and energy value because of the significant content of carbohydrates, in particular sugar-sand. The main drawback of marshmallow is the rapid process of its drying during storage due to the crystallization of sucrose and the gradual removal of moisture from the product. A method for obtaining marshmallow without sugar on the basis of high-conversion glucose syrup. In the work, experimental studies were carried out to determine the content and ratio of free and bound forms of moisture in marshmallow on the basis of sugars and on the basis of  high-conversion glucose syrup by Differential Scanning Calorimetry (DSC and Thermogravimetry (TG. To study the patterns of thermal effects on the properties of marshmallow samples, the non-isothermal analysis method and the synchronous thermal analysis instrument (TG-DTA / DSC of the STA 449 F3 Jupiter were used. In the process of thermal exposure, the samples decompose sugars and other organic compounds, as a result of which the sample weight decreases due to evaporation of moisture. The process of dehydration in a control sample of marshmallow using sugar occurs in a less wide temperature range than in a sample of marshmallow on the basis of  high-conversion glucose syrup, which indicates a greater degree of moisture bonding in the developed sample. A quantitative evaluation of the forms of moisture bonding in the samples was carried out using the experimental curves obtained by the TG method. From the temperature curves, the endothermic effects were determined, which correspond to the release of moisture with different forms and energies. Substitution of sugar for treacle in the formula of marshmallow reduces the share of free moisture and increases the safety of the product without signs of staling.

  15. TH-A-BRC-03: AAPM TG218: Measurement Methods and Tolerance Levels for Patient-Specific IMRT Verification QA

    Energy Technology Data Exchange (ETDEWEB)

    Miften, M. [University of Colorado School of Medicine (United States)

    2016-06-15

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  16. TH-A-BRC-03: AAPM TG218: Measurement Methods and Tolerance Levels for Patient-Specific IMRT Verification QA

    International Nuclear Information System (INIS)

    Miften, M.

    2016-01-01

    AAPM TG-135U1 QA for Robotic Radiosurgery - Sonja Dieterich Since the publication of AAPM TG-135 in 2011, the technology of robotic radiosurgery has rapidly developed. AAPM TG-135U1 will provide recommendations on the clinical practice for using the IRIS collimator, fiducial-less real-time motion tracking, and Monte Carlo based treatment planning. In addition, it will summarize currently available literature about uncertainties. Learning Objectives: Understand the progression of technology since the first TG publication Learn which new QA procedures should be implemented for new technologies Be familiar with updates to clinical practice guidelines AAPM TG-178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance - Steven Goetsch Purpose: AAPM Task Group 178 Gamma Stereotactic Radiosurgery Dosimetry and Quality Assurance was formed in August, 2008. The Task Group has 12 medical physicists, two physicians and two consultants. Methods: A round robin dosimetry intercomparison of proposed ionization chambers, electrometer and dosimetry phantoms was conducted over a 15 month period in 2011 and 2012 (Med Phys 42, 11, Nov, 2015). The data obtained at 9 institutions (with ten different Elekta Gamma Knife units) was analyzed by the lead author using several protocols. Results: The most consistent results were obtained using the Elekta ABS 16cm diameter phantom, with the TG-51 protocol modified as recommended by Alfonso et al (Med Phys 35, 11, Nov 2008). A key white paper (Med Phys, in press) sponsored by Elekta Corporation, was used to obtain correction factors for the ionization chambers and phantoms used in this intercomparison. Consistent results were obtained for both Elekta Gamma Knife Model 4C and Gamma Knife Perfexion units as measured with each of two miniature ionization chambers. Conclusion: The full report gives clinical history and background of gamma stereotactic radiosurgery, clinical examples and history, quality assurance recommendations and outline

  17. High-temperature Brillouin scattering study of haplogranitic glasses and liquids: Effects of F, K, Na and Li on Tg and elastic properties

    Science.gov (United States)

    Manghnani, M. H.; Hushur, A.; Williams, Q. C.; Dingwell, D. B.

    2010-12-01

    The density, compressibility and viscosity of silicate melts are important in understanding the thermodynamic and fluid dynamic properties of magmatic systems. Knowledge of the compressibility of silicate melts at 1 bar is an important component in the construction of accurate pressure-volume-temperature equations of state. In light of this, the velocity (nVp, Vp, Vs) and refractive index n of four anhydrous haplogranitic glasses and liquids with similar alkali abundances, but different cations, are measured at high temperature by Brillouin scattering spectroscopy through the glass transition temperature (Tg) in both platelet and back scattering geometry. The compositions of four haplogranites are 5 wt% of the components Li2O, Na2O, K2O and F each added to a base of haplogranitic (HPG8) composition. The glass transition temperature Tg of different haplogranite samples at the GHz frequency of the Brillouin probe are determined from the change in slope of the temperature-dependent longitudinal or transverse sound velocity. HPG8-Li5 has the lowest glass transition temperature (466°C), while HPG8-K5 has the highest glass transition temperature (575°C). Our Brillouin results, when compared with DSC measurements, show lower Tg values. This raises the possibility of a role of either heating rates or a frequency dependence of the glass transition in explaining the discrepancies in Tg values derived from the two methods. The sound velocity (nVp, Vp, Vs) shows markedly different temperature dependences (including differences in sign) below Tg depending on their different alkali contents. The unrelaxed elastic moduli of three haplogranitic glasses with added Li2O, Na2O and F components have been obtained as a function of temperature. The unrelaxed bulk modulus, shear modulus and Poisson’s ratio show strong compositional dependences at ambient temperature. On heating, The K initially decreases with increasing temperature up to ~ 135°C, then increases up to Tg, and then

  18. Short-term modern life-like stress exacerbates Aβ-pathology and synapse loss in 3xTg-AD mice.

    Science.gov (United States)

    Baglietto-Vargas, David; Chen, Yuncai; Suh, Dongjin; Ager, Rahasson R; Rodriguez-Ortiz, Carlos J; Medeiros, Rodrigo; Myczek, Kristoffer; Green, Kim N; Baram, Tallie Z; LaFerla, Frank M

    2015-09-01

    Alzheimer's disease (AD) is a progressive neurological disorder that impairs memory and other cognitive functions in the elderly. The social and financial impacts of AD are overwhelming and are escalating exponentially as a result of population aging. Therefore, identifying AD-related risk factors and the development of more efficacious therapeutic approaches are critical to cure this neurological disorder. Current epidemiological evidence indicates that life experiences, including chronic stress, are a risk for AD. However, it is unknown if short-term stress, lasting for hours, influences the onset or progression of AD. Here, we determined the effect of short-term, multi-modal 'modern life-like' stress on AD pathogenesis and synaptic plasticity in mice bearing three AD mutations (the 3xTg-AD mouse model). We found that combined emotional and physical stress lasting 5 h severely impaired memory in wild-type mice and tended to impact it in already low-performing 3xTg-AD mice. This stress reduced the number of synapse-bearing dendritic spines in 3xTg-AD mice and increased Aβ levels by augmenting AβPP processing. Thus, short-term stress simulating modern-life conditions may exacerbate cognitive deficits in preclinical AD by accelerating amyloid pathology and reducing synapse numbers. Epidemiological evidence indicates that life experiences, including chronic stress, are a risk for Alzheimer disease (AD). However, it is unknown if short stress in the range of hours influences the onset or progression of AD. Here, we determined the effect of short, multi-modal 'modern-lifelike'stress on AD pathogenesis and synaptic plasticity in mice bearing three AD mutations (the 3xTg-AD mouse model). We found that combined emotional and physical stress lasting 5 h severely impaired memory in wild-type mice and tended to impact it in already low-performing 3xTg-AD mice. This stress reduced the number of synapse-bearing dendritic spines in 3xTg-AD mice and increased Aβ levels by

  19. SU-E-T-468: Implementation of the TG-142 QA Process for Seven Linacs with Enhanced Beam Conformance

    Energy Technology Data Exchange (ETDEWEB)

    Woollard, J; Ayan, A; DiCostanzo, D; Grzetic, S; Hessler, J; Gupta, N [OH State University, Columbus, OH (United States)

    2015-06-15

    Purpose: To develop a TG-142 compliant QA process for 7 Varian TrueBeam linear accelerators (linacs) with enhanced beam conformance and dosimetrically matched beam models. To ensure consistent performance of all 7 linacs, the QA process should include a common set of baseline values for use in routine QA on all linacs. Methods: The TG 142 report provides recommended tests, tolerances and frequencies for quality assurance of medical accelerators. Based on the guidance provided in the report, measurement tests were developed to evaluate each of the applicable parameters listed for daily, monthly and annual QA. These tests were then performed on each of our 7 new linacs as they came on line at our institution. Results: The tolerance values specified in TG-142 for each QA test are either absolute tolerances (i.e. ±2mm) or require a comparison to a baseline value. The results of our QA tests were first used to ensure that all 7 linacs were operating within the suggested tolerance values provided in TG −142 for those tests with absolute tolerances and that the performance of the linacs was adequately matched. The QA test results were then used to develop a set of common baseline values for those QA tests that require comparison to a baseline value at routine monthly and annual QA. The procedures and baseline values were incorporated into a spreadsheets for use in monthly and annual QA. Conclusion: We have developed a set of procedures for daily, monthly and annual QA of our linacs that are consistent with the TG-142 report. A common set of baseline values was developed for routine QA tests. The use of this common set of baseline values for comparison at monthly and annual QA will ensure consistent performance of all 7 linacs.

  20. SU-E-T-468: Implementation of the TG-142 QA Process for Seven Linacs with Enhanced Beam Conformance

    International Nuclear Information System (INIS)

    Woollard, J; Ayan, A; DiCostanzo, D; Grzetic, S; Hessler, J; Gupta, N

    2015-01-01

    Purpose: To develop a TG-142 compliant QA process for 7 Varian TrueBeam linear accelerators (linacs) with enhanced beam conformance and dosimetrically matched beam models. To ensure consistent performance of all 7 linacs, the QA process should include a common set of baseline values for use in routine QA on all linacs. Methods: The TG 142 report provides recommended tests, tolerances and frequencies for quality assurance of medical accelerators. Based on the guidance provided in the report, measurement tests were developed to evaluate each of the applicable parameters listed for daily, monthly and annual QA. These tests were then performed on each of our 7 new linacs as they came on line at our institution. Results: The tolerance values specified in TG-142 for each QA test are either absolute tolerances (i.e. ±2mm) or require a comparison to a baseline value. The results of our QA tests were first used to ensure that all 7 linacs were operating within the suggested tolerance values provided in TG −142 for those tests with absolute tolerances and that the performance of the linacs was adequately matched. The QA test results were then used to develop a set of common baseline values for those QA tests that require comparison to a baseline value at routine monthly and annual QA. The procedures and baseline values were incorporated into a spreadsheets for use in monthly and annual QA. Conclusion: We have developed a set of procedures for daily, monthly and annual QA of our linacs that are consistent with the TG-142 report. A common set of baseline values was developed for routine QA tests. The use of this common set of baseline values for comparison at monthly and annual QA will ensure consistent performance of all 7 linacs

  1. Celiac disease or non-celiac gluten sensitivity? An approach to clinical differential diagnosis.

    Science.gov (United States)

    Kabbani, Toufic A; Vanga, Rohini R; Leffler, Daniel A; Villafuerte-Galvez, Javier; Pallav, Kumar; Hansen, Joshua; Mukherjee, Rupa; Dennis, Melinda; Kelly, Ciaran P

    2014-05-01

    Differentiating between celiac disease (CD) and non-celiac gluten sensitivity (NCGS) is important for appropriate management but is often challenging. We retrospectively reviewed records from 238 patients who presented for the evaluation of symptoms responsive to gluten restriction without prior diagnosis or exclusion of CD. Demographics, presenting symptoms, serologic, genetic, and histologic data, nutrient deficiencies, personal history of autoimmune diseases, and family history of CD were recorded. NCGS was defined as symptoms responsive to a gluten-free diet (GFD) in the setting of negative celiac serology and duodenal biopsies while on a gluten-containing diet or negative human leukocyte antigen (HLA) DQ2/DQ8 testing. Of the 238 study subjects, 101 had CD, 125 had NCGS, 9 had non-celiac enteropathy, and 3 had indeterminate diagnosis. CD subjects presented with symptoms of malabsorption 67.3% of the time compared with 24.8% of the NCGS subjects (Pdiseases (P=0.002), or nutrient deficiencies (P2× upper limit of normal IgA trans-glutaminase antibody (tTG) or IgA/IgG deaminated gliadan peptide antibody (DGP) with clinical response to GFD was 130 (confidence interval (CI): 18.5-918.3). The positive likelihood ratio of the combination of gluten-responsive symptoms and negative IgA tTG or IgA/IgG DGP on a regular diet for NCGS was 9.6 (CI: 5.5-16.9). When individuals with negative IgA tTG or IgA/IgG DGP also lacked symptoms of malabsorption (weight loss, diarrhea, and nutrient deficiencies) and CD risk factors (personal history of autoimmune diseases and family history of CD), the positive likelihood ratio for NCGS increased to 80.9. On the basis of our findings, we have developed a diagnostic algorithm to differentiate CD from NCGS. Subjects with negative celiac serologies (IgA tTG or IgA/IgG DGP) on a regular diet are unlikely to have CD. Those with negative serology who also lack clinical evidence of malabsorption and CD risk factors are highly likely to have

  2. Thermal behavior of biflorin by beans TG and a DSC photovisual system

    Directory of Open Access Journals (Sweden)

    C. F. S. Aragão

    Full Text Available This work proposes thermal characterization, of the biflorine, orto-quinon of Capraria biflora L., through the TG and DSC photovisual data. The thermogravimetric results showed that the decomposition reaction biflorine occurs three steps under air atmosphere, The DSC of biflorin presented five peaks relating to phase transitions. The DSC photovisual system demonstrated changes in biflorin.

  3. Gender-Specific Neuroimmunoendocrine Response to Treadmill Exercise in 3xTg-AD Mice

    Directory of Open Access Journals (Sweden)

    Lydia Giménez-Llort

    2010-01-01

    Full Text Available The 3xTg-AD mouse develops a progressive Alzheimer's disease- (AD- like brain pathology that causes cognitive- and neuropsychiatric-like symptoms of dementia. Since its neuroimmunoendocrine axis is likewise impaired, this mouse is also useful for modelling complex age-related neurodegeneration. This study analyzed behavioral, physiological, neurochemical, pathological and immunoendocrine alterations in male and female 3xTg-AD mice and assayed the effects of a short therapy of forced physical exercise at the moderate pathology stage of 6 months of age. Gender effects were observed in most AD-related pathology and dysfunctions. Five weeks of treadmill training produced beneficial effects, such as the reduction of brain oxidative stress and GABA-A receptor dysfunction in males and improvement of sensorimotor function in females. In both sexes, exercise decreased the brain amyloid 42/40 ratio levels. The results highlight the importance of analyzing experimental therapies in both mouse model genders in order to improve our understanding of the disease and develop more appropriate therapies.

  4. In-Situ Synchrotron X-ray Study of the Phase and Texture Evolution of Ceria and Superconductor Films Deposited by Chemical Solution Method

    DEFF Research Database (Denmark)

    Yue, Zhao; Grivel, Jean-Claude; He, Dong

    2012-01-01

    In situ synchrotron x-ray diffraction is used to study the phase and texture formation of ceria based films and superconductor films deposited by the chemical solution method on technical substrates. Combined analysis using in situ synchrotron x-ray diffraction, thermogravimetry/differential ther......In situ synchrotron x-ray diffraction is used to study the phase and texture formation of ceria based films and superconductor films deposited by the chemical solution method on technical substrates. Combined analysis using in situ synchrotron x-ray diffraction, thermogravimetry...

  5. ANÁLISES DE PROTOCOLOS TELETERÁPICOS DE CONTROLE DE QUALIDADE DE ALGUNS SERVIÇOS LOCAIS, BASEADOS NO TG40 E ARCAL XXX Routine teletherapy quality control protocols based on TG40 and ARCAL XXX

    Directory of Open Access Journals (Sweden)

    Carmen S. Guzmán Calcina

    2002-01-01

    Full Text Available Considerando a importância da garantia da qualidade nos serviços de radioterapia, este trabalho tem como primeiro objetivo fazer uma avaliação dos testes propostos pelos protocolos oficiais internacionais TG40 e ARCAL XXX para os equipamentos de cobalto, acelerador linear e simulador. O segundo objetivo consistiu em se fazer uma avaliação dos testes que atualmente são realizados por alguns serviços de radioterapia nacionais e da América Latina, comparando-os com os apresentados nos protocolos citados. Dos resultados obtidos, observou-se que embora o TG40 apresente os testes básicos necessários para um controle de qualidade adequado, o ARCAL ainda sugere testes complementares. Dos resultados e discussões, concluiu-se que é necessário que os serviços de radioterapia implementem os testes de controle de qualidade básicos e indispensáveis aos seus equipamentos, e que os demais testes sejam implementados de acordo com as suas necessidades e disponibilidades. Como produto deste estudo, sugestões de protocolos são apresentadas para o trabalho de rotina, provenientes da fusão dos protocolos analisados.In view of the great importance of quality control in radiotherapy services, this paper aimed primarily to evaluate the tests recommended by international protocols TG40 and ARCAL XXX for teletherapic equipments (cobalt, linear accelerator and simulator. A second objective was to evaluate the tests currently used in some radiotherapy services in Brazil and Latin America and to compare these tests with the ones recommended by the international protocols. Our results suggest that ARCAL is more complete than TG40, although the latter includes all the essential basic tests. We concluded that radiotherapy services should implement all basic quality control tests and that all other complementary tests should be implemented according to the need of each service. Finally, suggestions of protocols are presented, elaborated from the official and

  6. Radiodine administration under suppression of TSH for identification of false positive receptions in patients with thyroid differentiated carcinoma (TDC): utility of the potassium perchlorate

    International Nuclear Information System (INIS)

    Santangelo, L.A.; Pitoia, F.; Sanz, C.; Niepomniszcze, H.; El Tamer, Elias

    2004-01-01

    The total body scan, after a dose of 131 I correlated with the measurement of stimulated Tg, constitute the principal pillars in follow-up of patients with TDC (thyroid differentiated carcinoma). A bibliographical search revealed more than 70 situations that can cause false total body scans positive. The examination is essential to avoid unnecessary treatment with radioiodine. The object is to evaluate the effectiveness of the radioiodine administration under hormonal therapy thyroid suppressive (THST) to eliminate the possibility of a false total body scan positive in five patients with TDC with stimulated Tg <1ng/ml

  7. Characterization of the molecular distribution of drugs in glassy solid dispersions at the nano-meter scale, using differential scanning calorimetry and gravimetric water vapour sorption techniques

    NARCIS (Netherlands)

    van Drooge, D J; Hinrichs, W L J; Visser, M R; Frijlink, H W

    2006-01-01

    The molecular distribution in fully amorphous solid dispersions consisting of poly(vinylpyrrolidone) (PVP)-diazepam and inulin-diazepam was studied. One glass transition temperature (T-g), as determined by temperature modulated differential scanning calorimetry (TMDSC), was observed in PVP-diazepam

  8. Structure-to-property relationships in addition cured polymers. II - Resin Tg and composite initial mechanical properties of norbornenyl cured polyimide resins

    Science.gov (United States)

    Alston, William B.

    1986-01-01

    PRM (polymerization of monomeric reactants) methodology was used to prepare thirty different polyimide oligomeric resins. Monomeric composition as well as chain length between sites of crosslinks were varied to examine their effects on glass transition temperature (Tg) of the cured/postcured resins. An almost linear correlation of Tg versus molecular distance between the crosslinks was observed. An attempt was made to correlate Tg with initial mechanical properties (flexural strength and interlaminar shear strength) of unidirectional graphite fiber composites prepared with these resins. However, the scatter in mechanical strength data prevented obtaining as clear a correlation as was observed for the structural modification/crosslink distance versus Tg. Instead, only a range of composite mechanical properties was obtained at the test temperatures studied (room temperature, 288 and 316 C). Perhaps more importantly, what did become apparent during the attempted correlation study was: (1) that PMR methodology could be used to prepare composites from resins that contain a wide variety of monomer modifications, and (2) that these composites almost invariably provided satisfactory initial mechanical properties as long as the resins selected were melt processable.

  9. Correlations of serum levels of TG with leptin and other related factors (L-1, NPY adiponectin) in patients with hyperlipidaemia

    International Nuclear Information System (INIS)

    Wang Donghong; Yu Ping; Wei Jingjun

    2007-01-01

    Objective: To study the changes and correlations of serum levels of triglyeride (TG), leptin, L -1, neuropeptide Y (NPY) and adiponectin in patients with hypertriglyceridemia (HTG). Methods: Serum levels of TG, leptin, L-1, NPY and adiponectin in 54 patients with HTG and 55 controls were measured with radioimmunoassay (RIA). Results: The serum levels of TG, Leptin, L -1 and NPY in patients with HTG [ (3.46 ± 1.14) mmol/L, (10.56 ±3.79) μg/L, (0.40 ± 0.18) μg/L, (115.89 ± 24.56) μg/L, respectively] were significantly higher than those in controls [ (1.26 ± 0.30) mmol/L, (5.66 ± 2.01) μg/L, (0.22 ± 0.09) μg/L, (95.21 ± 16.85) μg/L, respectively] P < 0.01 in all. But serum levels of adiponectin in patients with HTG (8.98 ± 3.51μg/L) was significantly lower than those in controls [(13.21 ± 9.46) μg/L, P < 0.01]. There were significantly positive correlations between serum TG levels and serum levels of leptin (r = 0.576, P < 0.05). There were also significantly positive correlations between serum leptin levels and serum levels of L-1 and NPY (r = 0.582; r = 0.479, respectively, P < 0.05). Conclusion: There was close relationship between increase in serum TG level and changes of serum levels of leptin, L-1, NPY, adiponectin. Neural-endocrine-immune system participated in fatty metabolism and could result in HTG. (authors)

  10. Differential autophagy power in the spinal cord and muscle of transgenic ALS mice.

    Directory of Open Access Journals (Sweden)

    Valeria eCrippa

    2013-11-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a motoneuron disease characterized by misfolded proteins aggregation in affected motoneurons. In mutant SOD1 (mutSOD1 ALS models, aggregation correlates to impaired functions of proteasome and/or autophagy, both essential for the intracellular chaperone-mediated protein quality control (PQC, and a reduced mutSOD1 clearance from motoneurons. Skeletal muscle cells are also sensitive to mutSOD1 toxicity, but no mutSOD1 aggregates are formed in these cells, that might better manage mutSOD1 than motoneurons. Thus, we analysed in spinal cord and in muscle of transgenic (tg G93A-SOD1 at presymptomatic (PS, 8 weeks and symptomatic (S, 16 weeks stages, and in age-matched control mice, whether mutSOD1 differentially modulates relevant PQC players, such as HSPB8, BAG3, and BAG1. Possible sex differences were also considered. No changes of HSPB8, BAG3 and BAG1 at PS stage (8 weeks were seen in all tissues examined in tg G93A-SOD1 and control mice. At S stage (16 weeks, HSPB8 dramatically increased in skeletal muscle of tg G93A-SOD1 mice, while a minor increase occurred in spinal cord of male, but not female tg G93A-SOD1 mice. BAG3 expression increased both in muscle and spinal cord of tg G93A-SOD1 mice at S stage, BAG1 expression increased only in muscle of the same mice. Since, HSPB8-BAG3 complex assists mutSOD1 autophagic removal, we analysed two well-known autophagic markers, LC3 and p62. Both LC3 and p62 mRNAs were significantly up-regulated in skeletal muscle of tg G93A-SOD1 mice at S stage (16 weeks. This suggests that mutSOD1 expression induces a robust autophagic response specifically in muscle. Together these results demonstrate that, in muscle mutSOD1-induced autophagic response is much higher than in spinal cords. In addition, if mutSOD1 exerts toxicity in muscle, this may not be mediated by misfolded protein accumulation. It remains unclear whether in muscle mutSOD1 toxicity is related to aberrant autophagy

  11. SU-E-T-393: Using TG119 to Assess RapidArc at Hamad Medical Corporation.

    Science.gov (United States)

    Nobah, A; El-Kaissi, T; Hammoud, R; Al-Hammadi, N

    2012-06-01

    To provide a confidence level within our clinic relating to the implementation and administration of RapidArc, the AAPM TG1 19 has been implemented. This task group provides a sound and relatively simple methodology for determining the accuracy of the overall IMRT process administered in the day-to-day clinicMethods: Six different test plans, of varying complexity, were created on mock structure sets, downloaded from AAPM, and delivered. The treatment planning system results were then compared with the delivered results. Plans were created and delivered on a solid water phantom, using 25×25cm water equivalent slabs of varying thicknesses. Delivered point and planar dose measurements were obtained using an ionization chamber and film, respectively. The confidence limit (CL), averaged for all test plans, was calculated for the high dose point in the PTV and for the low dose point in the avoidance structure. This was used as an indicator of the uncertainty of the average difference between measured and planned dose. Where the precision of the delivery is based on how small the CL value is.For both the high and low dose points, the local CL's were determined to be 0.036 and 0.011, respectively. The range of results for the CL presented in TG1 19 varies from 0.015 to 0.098 for the high dose point, and from 0.014 to 0.086 for the low dose point. Our results indicate the accurate implementation of RapidArc within our clinic, especially when compared to the results of other institutions, published in TG1 19. Furthermore, the CL value for the low dose measurements is lower than any of the results published in TG119. We recommend that any clinic conducting IMRT should implement this task group. This will not only provide a greater understanding of the delivery and its limitations, but will also give the overall accuracy and consistency of the technique as it applies to the various treatment sites. © 2012 American Association of Physicists in Medicine.

  12. Age-dependent modifications of AMPA receptor subunit expression levels and related cognitive effects in 3xTg-AD mice

    Directory of Open Access Journals (Sweden)

    Pamela eCantanelli

    2014-08-01

    Full Text Available GluA1, GluA2, GluA3, and GluA4 are the constitutive subunits of AMPA receptors (AMPARs, the major mediators of fast excitatory transmission in the mammalian central nervous system. Most AMPARs are Ca2+-impermeable because of the presence of the GluA2 subunit. GluA2 mRNA undergoes an editing process that results in a Q to R substitution, a key factor in the regulation of AMPAR Ca2+-permeability. AMPARs lacking GluA2 or containing the unedited subunit are permeable to Ca2+ and Zn2+. The phenomenon physiologically modulates synaptic plasticity while, in pathologic conditions, leads to increased vulnerability to excitotoxic neuronal death. Given the importance of these subunits, we have therefore evaluated possible associations between changes in expression levels of AMPAR subunits and development of cognitive deficits in 3xTg-AD mice, a widely investigated transgenic mouse model of Alzheimer’s disease. With qRT-PCR, we assayed hippocampal mRNA expression levels of GluA1-4 subunits occurring in young [3 months of age (m.o.a.] and old (12 m.o.a Tg-AD mice and made comparisons with levels found in age-matched wild type (WT mice. Efficiency of GluA2 RNA editing was also analyzed. All animals were cognitively tested for short- and long-term spatial memory with the Morris Water Maze (MWM navigation task. 3xTg-AD mice showed age-dependent decreases of mRNA levels for all the AMPAR subunits, with the exception of GluA2. Editing remained fully efficient with aging in 3xTg-AD and WT mice. A one-to-one correlation analysis between MWM performances and GluA1-4 mRNA expression profiles showed negative correlations between GluA2 levels and MWM performances in young 3xTg-AD mice. On the contrary, positive correlations between GluA2 mRNA and MWM performances were found in young WT mice. Our data suggest that increases of AMPARs that contain GluA1, GluA3, and GluA4 subunits may help in maintaining cognition in pre-symptomatic 3xTg-AD mice.

  13. High-Tg TOPAS microstructured polymer optical fiber for fiber Bragg grating strain sensing at 110 degrees

    DEFF Research Database (Denmark)

    Markos, Christos; Stefani, Alessio; Nielsen, Kristian

    2013-01-01

    We present the fabrication and characterization of fiber Bragg gratings (FBGs) in an endlessly single-mode microstructured polymer optical fiber (mPOF) made of humidity-insensitive high-Tg TOPAS cyclic olefin copolymer. The mPOF is the first made from grade 5013 TOPAS with a glass transition...... temperature of Tg = 135°C and we experimentally demonstrate high strain operation (2.5%) of the FBG at 98°C and stable operation up to a record high temperature of 110°C. The Bragg wavelengths of the FBGs are around 860 nm, where the propagation loss is 5.1dB/m, close to the fiber loss minimum of 3.67d...

  14. Sub-Tg enthalpy relaxation in an unstable oxide glass former: insights into the structural heterogeneity

    DEFF Research Database (Denmark)

    Yue, Yuanzheng; Zhang, Yanfei

    Structural heterogeneity plays a crucial role in determining functionality of glasses. In this work we have found that the sub-Tg enthalpy relaxation pattern in a hyperquenched glass is highly sensitive to structural heterogeneity. As a consequence, the former can be used as an effective approach...... to detect and quantify the structural heterogeneity in glass-forming liquids. However, the chemical nature of structural heterogeneity should be revealed by other means such as high resolution microscopic and spectroscopic methods. To study the impact of the structural heterogeneity on the sub-Tg relaxation...... chemical features and degrees of structural heterogeneity in glass-forming liquids. This finding contributes to the microscopic origin of both the primary and secondary relaxation in terms of structural heterogeneity. Finally the results provide insights into the relation between structural heterogeneity...

  15. Thermal analysis and FTIR studies of sewage sludge produced in treatment plants. The case of sludge in the city of Uberlandia-MG, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Silva, Jader de [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Departamento Municipal de Agua e Esgoto de Uberlandia (DMAE) (Brazil); Filho, Guimes Rodrigues, E-mail: guimes@ufu.br [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Silva Meireles, Carla da; Dias Ribeiro, Sabrina; Vieira, Julia Graciele [Instituto de Quimica da Universidade Federal de Uberlandia, Av. Joao Naves de Avila, 2121, CEP 38400-902, Cx. Postal 593, Uberlandia - Minas Gerais (Brazil); Vieira da Silva, Cleuzilene [Faculdade de Engenharia Quimica da Universidade Federal de Uberlandia (Brazil); Alves Cerqueira, Daniel [Instituto de Ciencias Ambientais e Desenvolvimento Sustentavel da Universidade Federal da Bahia (Brazil)

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer In this study, the sludge was characterized by thermal analyses and FTIR. Black-Right-Pointing-Pointer The superior calorific value of the sludge was 16.2 MJ kg{sup -1}. Black-Right-Pointing-Pointer The sludge showed a significant biodegradable portion of 65%. Black-Right-Pointing-Pointer The UASB sludge can be used for energy source. - Abstract: The operation of anaerobic reactors in Brazil creates a by-product, sewage sludge, for which adequate treatment is necessary to obtain a solid and stable material. The burning of sewage sludge may be an effective alternative for its management, and looking to enhance its energy potential, an environmentally friendly method of disposal is necessary. As the quantity of sludge generated has increased over the past few years, the physical chemical characterization of this waste is the first stage for its utilization as raw material. The material was characterized by thermal analyses (Thermogravimetry (TG)/Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC)) and Infrared Analysis (FTIR) in order to determine the main organic groups present in sludge. The calorific power of the anaerobically digested sludge of Uberlandia-MG, Brazil was measured, and an energy content equal to 16.2 MJ kg{sup -1} was found, which is within the range of values reported in the literature.

  16. Thermal transformations of oxohalide complexes of rhenium(5) and molybdenum(5) with diazo-18-crown-6 in solid phase

    International Nuclear Information System (INIS)

    Ashurova, N.Kh.; Yakubov, K.G.

    1992-01-01

    Methods for synthesis and separation in solid state of the rhenium(5) and molybdenum(5) onium complexes with diaza-18-crown-6(L), the content of which according to the data of elementary analysis, IRS in the close and remote areas, thermogravimetry, conductometry and potentiometry corresponds to the (H 2 L)[EOX 5 ], where E = Re, Mo; X = Cl - , Br - . Thermotransformation of onium compounds is studied by methods of thermal methods (TG-DTG-DTA combined study). Their avility to be affected by solid-phase dehydrohalogenization, e.i. anderson regrouping. The thermolysis products, corresponding to the general formula (EOLX 3 ), are separated and studied

  17. European Science Notes Information Bulletin Reports on Current European/Middle Eastern Science,

    Science.gov (United States)

    1988-05-01

    can be added, giving rise to reactions of the type The Instituto de Ceramica y Vidrio , the ceramics and 4ZrSiO4 +4AI203 + CaO -- 4ZrO2 + AI6Si2013...well-chosen. Sol-Gel Processing Reaction Sintering of ZrO2-A1203- SiO2 The institute, in a collaborative program with the University of Sheffield, UK...thermogravimetry (TG), and optical 30 AI203. 70 SiO2 (1120/I’OS 10, EtOH/TEOS 20, HCI/EOS 0.2) absorption techniques. They have observed that organic 30

  18. Differential diagnosis of mitochondrial neurogastrointestinal encephalomyopathy. First clinical description in Russia

    Directory of Open Access Journals (Sweden)

    S. A. Kurbatov

    2015-01-01

    Full Text Available Mitochondrial neurogastrointestinal encephalomyopathy syndrome (MNGIE is a rare autosomal recessive progressive multisystem disorder. Most of MNGIE is caused by mutations in the gene encoding thymidine phosphorylase (TYMP, locus 22q13. Mitochondrial dysfunction represents multiple deletions and depletion of mtDNA. We present a case of MNGIE with a novel mutation in the position c.1001T>G of TYMP gene, hypergonadotropic hypogonadism, decrement of compound muscle action potential following repetitive nerve stimulation on EMG which was not previously described in literature and differential diagnoses MNGIE with other conditions.

  19. The flame retardant DE-71 (a mixture of polybrominated diphenyl ethers inhibits human differentiated thyroid cell function in vitro.

    Directory of Open Access Journals (Sweden)

    Thit Mynster Kronborg

    Full Text Available Normal thyroid function is essential for general growth and metabolism, but can be affected by endocrine disrupting chemicals (EDCs. Polybrominated diphenyl ethers (PBDEs have been used worldwide to reduce flammability in different materials and are suspected to be EDCs. The production of the commercial Penta- and OctaBDE mixtures is banned, but DecaBDEs and existing products may leak PBDEs into the environment. Our aim was to investigate the effect of the PentaBDE mixture DE-71 on human thyroid cells in vitro.Primary human thyroid cells were obtained as paraadenomatous tissue and cultured in monolayers. The influence of DE-71 on cyclic adenosine monophosphate (cAMP and thyroglobulin (Tg production was examined in the culture medium by competitive radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Real-time quantitative PCR analysis of thyroid-specific genes was performed on the exposed cell cultures. PBDE concentrations were determined in cellular and supernatant fractions of the cultures.DE-71 inhibited Tg-release from TSH-stimulated thyrocytes. At 50 mg/L DE-71, mean Tg production was reduced by 71.9% (range: 8.5-98.7%, and cAMP by 95.1% (range: 91.5-98.8% compared to controls. Expression of mRNA encoding Tg, TPO and TSHr were significantly inhibited (p<0.0001, p = 0.0079, and p = 0.0002, respectively. The majority of DE-71 added was found in the cell fraction. No cytotoxicity was found.DE-71 inhibited differentiated thyroid cell functions in a two phase response manner and a concentration-dependent inhibition of Tg and cAMP production, respectively, as well as expression of mRNA encoding Tg, TPO and TSHr. Our findings suggest an inhibiting effect of PBDEs on thyroid cells.

  20. On the oxygen deficiency of high-Tc Y1Ba2Cu3O7-μ ceramics

    International Nuclear Information System (INIS)

    Szasz, A.; Dankhazi, Z.; Kojnok, J.; Trager, T.; Matrai, J.; Gyorgy, I.; Kirchmayr, H.; Mueller, H.; Watson, L.M.

    1991-01-01

    The role of oxygen deficiency in Y 1 Ba 2 Cu 3 O 7-μ ceramics was investigated by differential thermal analysis (DTA), differential thermogravimetry (DTG), linear thermal expansion (LTE), and by soft x-ray fluorescence spectroscopy (SXFS). The interdependence of the measured parameters and some of the stability criteria are discussed

  1. The triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio as a predictor of β-cell function in African American women.

    Science.gov (United States)

    Maturu, Amita; DeWitt, Peter; Kern, Philip A; Rasouli, Neda

    2015-05-01

    The TG/HDL-C ratio is used as a marker of insulin resistance (IR) in Caucasians. However, there are conflicting data on TG/HDL-C ratio as a predictor of IR in African Americans. Compared to Caucasians, African Americans have lower TG levels and increased insulin levels despite a greater risk for diabetes. We hypothesized that the TG/HDL-C ratio is predictive of IR and/or β-cell function in African American (AA) women. Non-diabetic AA women (n = 41) with a BMI > 25 kg/m(2) underwent frequently sampled intravenous glucose tolerance test (FSIGTT). Insulin sensitivity (SI) and the acute insulin response to glucose (AIRg) were measured using minimal model and β-cell function was determined by disposition index (DI = S I*AIRg). IR was defined as the lowest tertile of SI ( 0.70 was defined as significant discrimination. The mean (± SD) age was 38.5 ± 11.3 years, with BMI of 33.5 ± 6.7 kg/m(2) and fasting glucose of 86.5 ± 10.5 mg/dL. The AUC-ROC for the prediction of DI women. However, we did show an inverse association between the TG/HDL-C ratio and β-cell function, suggesting that this simple tool may effectively identify AA women at risk for DM2. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Análise TG-ROC de testes de imunofluorescência no diagnóstico de leishmaniose visceral canina Análisis TG-ROC de pruebas de inmunofluorescencia en el diagnóstico de leishmaniasis visceral canina TG-ROC analysis of immunofluorescence assays in canine visceral leishmaniasis diagnosis

    Directory of Open Access Journals (Sweden)

    Rita Maria da Silva

    2009-12-01

    Full Text Available OBJETIVO: Analisar a acurácia do diagnóstico de dois protocolos de imunofluorescência indireta para leishmaniose visceral canina. MÉTODOS: Cães provenientes de inquérito soroepidemiológico realizado em área endêmica nos municípios de Araçatuba e de Andradina, na região noroeste do estado de São Paulo, em 2003, e área não endêmica da região metropolitana de São Paulo, foram utilizados para avaliar comparativamente dois protocolos da reação de imunofluorescência indireta (RIFI para leishmaniose: um utilizando antígeno heterólogo Leishmania major (RIFI-BM e outro utilizando antígeno homólogo Leishmania chagasi (RIFI-CH. Para estimar acurácia utilizou-se a análise two-graph receiver operating characteristic (TG-ROC. A análise TG-ROC comparou as leituras da diluição 1:20 do antígeno homólogo (RIFI-CH, consideradas como teste referência, com as diluições da RIFI-BM (antígeno heterólogo. RESULTADOS: A diluição 1:20 do teste RIFI-CH apresentou o melhor coeficiente de contingência (0,755 e a maior força de associação entre as duas variáveis estudadas (qui-quadrado=124,3, sendo considerada a diluição-referência do teste nas comparações com as diferentes diluições do teste RIFI-BM. Os melhores resultados do RIFI-BM foram obtidos na diluição 1:40, com melhor coeficiente de contingência (0,680 e maior força de associação (qui-quadrado=80,8. Com a mudança do ponto de corte sugerido nesta análise para a diluição 1:40 da RIFI-BM, o valor do parâmetro especificidade aumentou de 57,5% para 97,7%, embora a diluição 1:80 tivesse apresentado a melhor estimativa para sensibilidade (80,2% com o novo ponto de corte. CONCLUSÕES: A análise TG-ROC pode fornecer importantes informações sobre os testes de diagnósticos, além de apresentar sugestões sobre pontos de cortes que podem melhorar as estimativas de sensibilidade e especificidade do teste, e avaliá-los a luz do melhor custo

  3. Roles of TgAb and TPOAb in the development of hypothyroidism after 131I treatment in hyperthyroid patients with Graves' disease

    International Nuclear Information System (INIS)

    Han Yunfeng; Tong Liangqian; Lan Qiong; Zhu Xiaohua; Chen Jing; Zhao Ming

    2012-01-01

    To evaluate the roles of antithyroid peroxidase antibodies (TPOAb) and antithyroglobulin antibodies (TbAb) in the development of hypothyroidism after 131 I treatment in hyperthyroid patients with Graves' disease (GD), data were collected from 160 GD patients who were treated with 131 I in the department of nuclear medicine of Tongji Hospital between January 2008 and February 2011. Patients were divided into four groups: group A (TgAb 131 I. The incidence of hypothyroidism after 131 I treatment was different for each group(P=0.034 131 I treatment. In conclusion, because TgAb and TPOAb play important roles in the occurrence of hypothyroidism after 131 I therapy, in patients with positive levels of TgAb and TPOAb, lower doses of 131 I might prevent hypothyroidism. (authors)

  4. A study of photothermal laser ablation of various polymers on microsecond time scales.

    Science.gov (United States)

    Kappes, Ralf S; Schönfeld, Friedhelm; Li, Chen; Golriz, Ali A; Nagel, Matthias; Lippert, Thomas; Butt, Hans-Jürgen; Gutmann, Jochen S

    2014-01-01

    To analyze the photothermal ablation of polymers, we designed a temperature measurement setup based on spectral pyrometry. The setup allows to acquire 2D temperature distributions with 1 μm size and 1 μs time resolution and therefore the determination of the center temperature of a laser heating process. Finite element simulations were used to verify and understand the heat conversion and heat flow in the process. With this setup, the photothermal ablation of polystyrene, poly(α-methylstyrene), a polyimide and a triazene polymer was investigated. The thermal stability, the glass transition temperature Tg and the viscosity above Tg were governing the ablation process. Thermal decomposition for the applied laser pulse of about 10 μs started at temperatures similar to the start of decomposition in thermogravimetry. Furthermore, for polystyrene and poly(α-methylstyrene), both with a Tg in the range between room and decomposition temperature, ablation already occurred at temperatures well below the decomposition temperature, only at 30-40 K above Tg. The mechanism was photomechanical, i.e. a stress due to the thermal expansion of the polymer was responsible for ablation. Low molecular weight polymers showed differences in photomechanical ablation, corresponding to their lower Tg and lower viscosity above the glass transition. However, the difference in ablated volume was only significant at higher temperatures in the temperature regime for thermal decomposition at quasi-equilibrium time scales.

  5. Long-term phenylbutyrate administration prevents memory deficits in Tg2576 mice by decreasing Abeta.

    Science.gov (United States)

    Ricobaraza, Ana; Cuadrado-Tejedor, Mar; Garcia-Osta, Ana

    2011-06-01

    Aberrations in protein folding, processing, and/or degradation are common features of neurodegenerative diseases, such as Alzheimer's disease (AD). Sodium 4-phenylbutyrate (PBA) is a well-known histone deacetylase inhibitor, which increases gene transcription of a number of genes, and also exerts neuroprotective effects. PBA acts as a chemical chaperone reducing the load of mutant or unfolded proteins during cellular stress. Previously, we reported that 5-week administration of PBA reinstated memory loss and dendritic spine densities in the Tg2576 mouse model of AD. In this study we reported that chronic administration of PBA, starting before the onset of disease symptoms (6 month-old) prevents age-related memory deficits in Tg2576 mice. The amelioration of the memory impairment is associated to a decrease in amyloid beta pathology and the glial fibrillary acidic protein (GFAP), suggesting that inflammation was reduced in PBA-treated animals. Together, the beneficial effects of PBA make it a promising agent for the prevention of AD.

  6. Cheese whey protein recovery by ultrafiltration through transglutaminase (TG) catalysis whey protein cross-linking.

    Science.gov (United States)

    Wen-Qiong, Wang; Lan-Wei, Zhang; Xue, Han; Yi, Lu

    2017-01-15

    In whey ultrafiltration (UF) production, two main problems are whey protein recovery and membrane fouling. In this study, membrane coupling protein transglutaminase (TG) catalysis protein cross-linking was investigated under different conditions to find out the best treatment. We found that the optimal conditions for protein recovery involved catalyzing whey protein cross-linking with TG (40U/g whey proteins) at 40°C for 60min at pH 5.0. Under these conditions, the recovery rate was increased 15-20%, lactose rejection rate was decreased by 10%, and relative permeate flux was increase 30-40% compared to the sample without enzyme treatment (control). It was noticeable that the total resistance and cake resistance were decreased after enzyme catalysis. This was mainly due to the increased particle size and decreased zeta potential. Therefore, membrane coupling enzyme catalysis protein cross-linking is a potential means for further use. Copyright © 2016. Published by Elsevier Ltd.

  7. Role of humidity and other correction factors in the AAPM TG-21 dosimetry protocol

    International Nuclear Information System (INIS)

    Rogers, D.W.; Ross, C.K.

    1988-01-01

    A detailed derivation is presented of the formulas required to determine Ngas and Dmed in the AAPM TG-21 dosimetry protocol. This protocol specifies how to determine the absorbed dose in an electron or photon beam when using exposure or absorbed dose calibrated ion chambers. It is shown that the expression given in TG-21's recent letter of clarification is incorrect. Accounting for humidity correctly increases, by 0.4%, all absorbed dose determinations using an exposure calibrated ion chamber. Taking into account other correction factors in the equation for exposure could also have varying, but significant effects (possibly over 1%). These are the stem scatter correction, the axial nonuniformity correction and the electrode correction for electrodes made of different materials from the wall. Attention is drawn to differences in the definitions of the exposure and absorbed dose calibration factors, Nx and ND, respectively, as supplied by the NBS and the NRCC

  8. Mineral conversion and microstructure change in the melting process of Shenmu coal ash

    Energy Technology Data Exchange (ETDEWEB)

    Yang Jianguo; Deng Furong; Zhao Hong; Cen Kefa [Zhejiang University, Hangzhou (China). State Key Laboratory of Clean Energy Utilization

    2007-05-15

    China has rich reserves of Shenmu coal, which has the typical characteristic of low-melting-point ash. If used in the pulverized-coal boiler of a power plant, Shenmu coal would cause serious slagging. In order to solve the slagging problem of Shenmu coal, the melting mechanism of Shenmu coal ash was studied. One of the Shenmu coals - Wenjialiang coal - was selected for the study. Using thermogravimetry-differential scanning colorimetry (TG-DSC) methods, the change of the coal ash's physicochemistry with temperature was studied. The typical temperature points in the melting process were obtained. Ash samples of the different temperature points were prepared in a high-temperature furnace with parameters similar to those used in the TG-DSC test, and were then cooled quickly in water. Later, the ash samples were analyzed using X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) methods in detail. Wenjialiang coal ash started to melt at 980{sup o}C. The ash was found to melt to a great extent at 1200{sup o}C and formed a multiform microstructure. At 1260{sup o}C, it was found to melt into a dense body with many pores, and formed a piece of vitreous body at 1340{sup o}C. Anorthite and gehlenite are the intermediate products that exist between 980 and 1340{sup o}C. They may be the main cause of the ash having low melting points, so that they could convert into a eutectic at low temperatures.

  9. Investigation on the ignition, thermal acceleration and characteristic temperatures of coal char combustion

    International Nuclear Information System (INIS)

    Zhang, Bin; Fu, Peifang; Liu, Yang; Yue, Fang; Chen, Jing; Zhou, Huaichun; Zheng, Chuguang

    2017-01-01

    Highlights: • A new thermal model and measuring method for the ignition temperature are proposed. • Ignition occurs in a region but not a point with ambient conditions changing. • Ignition region is measured from the minimum to maximum ignition temperature. • T_i_g_,_m_a_x of coal char in TG-DSC is in line with the ignition temperature of EFR. - Abstract: Through using a new thermal analysis model and a method of coal/char combustion, the minimum ignition temperature and minimum ignition heat of three different ranks of pulverized coal char were measured by simultaneous Thermogravimetry and Differential Scanning Calorimetry (TG-DSC) experiments. The results show that the ignition of coal char occurs in the range between the minimum ignition temperature and the inflection-point temperature. The thermal acceleration and its gradient G_T increase with increasing heating rate and decrease with increasing coal char rank. The higher the G_T of the coal char, the more easily the ignition occurs and more rapidly the burning and burnout occur. The data show that the G_T of coal char of SLH lignite is 1.6 times more than that of coal char of ZCY bituminous and JWY anthracite in ignition zone, and 3.4 times in burning zone. The characteristic temperatures increase with increasing temperature of prepared char, heating rate and char rank. Moreover, the T_i_g_,_m_a_x calculated in DSC experiment is approximately in line with the ignition temperature obtained in the entrained flow reactor, which demonstrates the feasibility of the proposed theory.

  10. Synthesis and performances of novel solid–solid phase change materials with hexahydroxy compounds for thermal energy storage

    International Nuclear Information System (INIS)

    Chen, Changzhong; Liu, Wenmin; Wang, Hongwei; Peng, Kelin

    2015-01-01

    Highlights: • Three new kinds of SSPCMs were synthesized with different skeleton materials. • The phase change properties and thermal stability of SSPCMs were investigated. • The maximum enthalpy in heating (cooling) process is 107.5 kJ/kg (102.9 kJ/kg). • The rigid groups and crosslinking structure of SSPCMs improve the thermal stability. • The SSPCMs could be applied in the temperature range of 30–70 °C. - Abstract: Three kinds of new polymeric SSPCMs with different crosslinking structures were synthesized and characterized for thermal energy storage. In the SSPCMs, three hexahydroxy compounds (sorbitol, dipentaerythritol and inositol) were individually employed as the molecular skeleton and polyethylene glycol (PEG) was used as the phase change functional chain. The molecular structure, crystalline properties, phase change behaviors, thermal reliability and stability of the synthesized SSPCMs were investigated by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetry (TG), respectively. The results show that the prepared SSPCMs possess high thermal energy storage density and an applicable temperature range of 30–70 °C, and the maximum phase change enthalpy in the heating and cooling process for the SSPCMs is 107.5 kJ/kg and 102.9 kJ/kg, respectively. The prepared SSPCMs have good reusability, excellent thermal reliability and stability from the heating-cooling thermal cycle test and TG curves. The resultant SSPCMs could be potentially applied in the areas of thermal energy storage and temperature-control

  11. Critical Assessment of Analytical Techniques in the Search for Biomarkers on Mars: A Mummified Microbial Mat from Antarctica as a Best-Case Scenario

    Science.gov (United States)

    Blanco, Yolanda; Gallardo-Carreño, Ignacio; Ruiz-Bermejo, Marta; Puente-Sánchez, Fernando; Cavalcante-Silva, Erika; Quesada, Antonio; Prieto-Ballesteros, Olga; Parro, Víctor

    2017-10-01

    The search for biomarkers of present or past life is one of the major challenges for in situ planetary exploration. Multiple constraints limit the performance and sensitivity of remote in situ instrumentation. In addition, the structure, chemical, and mineralogical composition of the sample may complicate the analysis and interpretation of the results. The aim of this work is to highlight the main constraints, performance, and complementarity of several techniques that have already been implemented or are planned to be implemented on Mars for detection of organic and molecular biomarkers on a best-case sample scenario. We analyzed a 1000-year-old desiccated and mummified microbial mat from Antarctica by Raman and IR (infrared) spectroscopies (near- and mid-IR), thermogravimetry (TG), differential thermal analysis, mass spectrometry (MS), and immunological detection with a life detector chip. In spite of the high organic content (ca. 20% wt/wt) of the sample, the Raman spectra only showed the characteristic spectral peaks of the remaining beta-carotene biomarker and faint peaks of phyllosilicates over a strong fluorescence background. IR spectra complemented the mineralogical information from Raman spectra and showed the main molecular vibrations of the humic acid functional groups. The TG-MS system showed the release of several volatile compounds attributed to biopolymers. An antibody microarray for detecting cyanobacteria (CYANOCHIP) detected biomarkers from Chroococcales, Nostocales, and Oscillatoriales orders. The results highlight limitations of each technique and suggest the necessity of complementary approaches in the search for biomarkers because some analytical techniques might be impaired by sample composition, presentation, or processing.

  12. Structural stability of PAN fiber under high electron beam radiation doses

    International Nuclear Information System (INIS)

    Pino, Eddy S.; Machado, Luci D.B.; Arruda, Clarissa P. Zelinschi de; Carvalho, Alvaro A. Silva de; Giovedi, Claudia

    2009-01-01

    Fiber-reinforced composite are an important class of engineering material. A relevant task of composite technology in order to produce materials for structures of high mechanical performance is to obtain the best carbon fiber. One of the main ways to produce carbon fibers of high Young's modulus and tensile strength is to use as starting material polyacrylonitrile (PAN) fibers which after a rigorous and carefully thermal process become carbon fibers. Since some chemical modifications produced in the thermal treatment can be induced by ionizing radiation, the aim of this paper is to evaluate the effect of high electron beam (EB) doses on a commercial PAN fiber in order to evaluate the use of this technology as an alternative treatment to improve the properties and characteristics of the produced carbon fiber. The doses applied were: 0.2, 0.4, 0.6, 0.8, 1.0 and 1.2 MGy. The irradiation effects induced on the PAN fiber were evaluated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and thermogravimetry (TG). FTIR obtained data have shown that the main functional groups remain practically unchanged in the non-irradiated and irradiated samples. The single DSC exothermic peak obtained for non-irradiated sample, becomes a double peak after the irradiation, presenting lower initial and higher final temperatures for exothermic DSC curves. The enthalpy involved in the chemical reaction decreases for irradiated samples as compared with the non-irradiated PAN fiber. TG data have shown that irradiated samples start a decomposition process at lower temperatures compared to the non-irradiated sample. (author)

  13. Synthesis of a Cationic Polyacrylamide under UV Initiation and Its Flocculation in Estrone Removal

    Directory of Open Access Journals (Sweden)

    Jiaoxia Sun

    2018-01-01

    Full Text Available A ternary cationic polyacrylamide (CPAM with the hydrophobic characteristic was prepared through ultraviolet- (UV- initiated polymerization technique for the estrone (E1 environmental estrogen separation and removal. The monomers of acrylamide (AM, acryloyloxyethyl-trimethyl ammonium chloride (DAC, and acryloyloxyethyl dimethylbenzyl ammonium chloride (AODBAC were used to synthesize the ternary copolymer (PADA. Fourier transform infrared spectroscopy (FT-IR, 1H nuclear magnetic resonance spectroscopy (1H NMR, thermogravimetry/differential scanning calorimetry (TG/DSC, and scanning electron microscopy (SEM were employed to characterize the structure, thermal decomposition property, and morphology of the polymers, respectively. FT-IR and 1H NMR results indicated the successful formation of the polymers. Besides, with the introduction of hydrophobic groups (phenyl group, an irregular and porous surface morphology and a favorable thermal stability of the PADA were observed by SEM and TG/DSC analyses, respectively. At the optimal condition (pH = 7, flocculant dosage = 4.0 mg/L and E1 concentration = 0.75 mg/L, an excellent E1 flocculation performance (E1 removal rate: 90.1%, floc size: 18.3 μm, and flocculation kinetics: 22.69×10-4 s−1 was acquired by using the efficient flocculant PADA-3 (cationic degree = 40%, and intrinsic viscosity = 6.30 dL·g−1. The zeta potential and floc size analyses were used to analyze the possible flocculation mechanism for the E1 removal. Results indicated that the charge neutralization, adsorption, and birding effects were dominant in the E1 removal progress.

  14. Radiation-induced grafting of styrene onto poly-vinylidene fluoride) film by simultaneous method with two different solvents

    International Nuclear Information System (INIS)

    Ferreira, H.P.; Parra, D.F.; Lugao, A.B.

    2011-01-01

    Complete text of publication follows. Radiation-induced grafting to create membranes with ion exchange capacity in fluorinated polymers has been studied for applications such as fuel cells, filtration and waste treatment and polymeric actuators due to their good physical and chemical properties. In this work, radiation-induced grafting of styrene into poly(vinylidene fluoride) (PVDF) films with 0.125 mm thickness at doses of 1 and 2.5 kGy in the presence of a styrene/N,N- dimethylformamide (DMF) solution (1:1, v/v) and at doses of 20, 40 and 80 kGy in presence of a styrene/toluene solution (1:1, v/v) at dose rate of 5 kGy h-1 was carried out by simultaneous method under nitrogen atmosphere and at room temperature, using gamma-rays form a Co-60. The films were characterized before and after modification by the grafting yield (GY), infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetry (TG/DTG). GY results shows that grafting increases with dose, and it was possible to confirm the grafting of styrene by FT-IR due to the new characteristics peaks and by the TG and DSC due to changes in thermal behavior of the grafted material. Results showed that the system allows the homogeneous grafting of styrene into PVDF using gamma irradiation at doses as low as 1 kGy when DMF is used and heterogeneous grafting when toluene is used, showing the importance of the solvent nature during the simultaneous method.

  15. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

    International Nuclear Information System (INIS)

    Sofronia, Ancuta M.; Baies, Radu; Anghel, Elena M.; Marinescu, Cornelia A.; Tanasescu, Speranta

    2014-01-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m 2 /g by calcination. • Raman spectra indicate the presence of B-type CO 3 group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample

  16. Thermal and structural characterization of synthetic and natural nanocrystalline hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Sofronia, Ancuta M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Baies, Radu [National Research Institute for Electrochemistry and Condensed Matter, 300224 Timisoara (Romania); Anghel, Elena M. [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Marinescu, Cornelia A., E-mail: alcorina@chimfiz.icf.ro [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania); Tanasescu, Speranta [Ilie Murgulescu Institute of Physical Chemistry of the Romanian Academy, 060021 Bucharest (Romania)

    2014-10-01

    The aim of this work was to study the thermal stability on heating and to obtain the processing parameters of synthetic and bone-derived hydroxyapatite over temperatures between room temperature and 1400 °C by thermal analysis (thermogravimetry (TG)/differential scanning calorimetry (DSC) and thermo-mechanical analysis—TMA). Structural and surface modifications related to samples origin and calcination temperature were investigated by Fourier transformed infrared (FTIR) and Raman spectroscopy, X-ray diffraction (XRD) and BET method. FTIR spectra indicated that the organic constituents and carbonate are no longer present in the natural sample calcined at 800 °C. Raman spectra highlighted the decomposition products of the hydroxyapatite. The calcination treatment modifies the processes kinetics of the synthetic samples, being able to isolate lattice water desorption processes of decarbonization and the dehydroxylation processes. Shrinkage of calcined synthetic sample increases by 10% compared to uncalcined synthetic powder. From the TMA correlated with TG analysis and heat capacity data it can be concluded that sintering temperature of the synthetic samples should be chosen in the temperature range of the onset of dehydroxylation and the temperature at which oxyapatite decomposition begins. - Highlights: • Specific surface area of HA powder was reduced from 19.2 to 9.5 m{sup 2}/g by calcination. • Raman spectra indicate the presence of B-type CO{sub 3} group in HA synthetic samples. • The onset temperature of HA densification and dehydroxylation processes correspond. • Calcination of HA influences reactions kinetics with consequences on densification. • Shrinkage of calcined HA sample increases by 10% with respect to uncalcined sample.

  17. NOG-hIL-4-Tg, a new humanized mouse model for producing tumor antigen-specific IgG antibody by peptide vaccination.

    Directory of Open Access Journals (Sweden)

    Yoshie Kametani

    Full Text Available Immunodeficient mice transplanted with human peripheral blood mononuclear cells (PBMCs are promising tools to evaluate human immune responses to vaccines. However, these mice usually develop severe graft-versus-host disease (GVHD, which makes estimation of antigen-specific IgG production after antigen immunization difficult. To evaluate antigen-specific IgG responses in PBMC-transplanted immunodeficient mice, we developed a novel NOD/Shi-scid-IL2rγnull (NOG mouse strain that systemically expresses the human IL-4 gene (NOG-hIL-4-Tg. After human PBMC transplantation, GVHD symptoms were significantly suppressed in NOG-hIL-4-Tg compared to conventional NOG mice. In kinetic analyses of human leukocytes, long-term engraftment of human T cells has been observed in peripheral blood of NOG-hIL-4-Tg, followed by dominant CD4+ T rather than CD8+ T cell proliferation. Furthermore, these CD4+ T cells shifted to type 2 helper (Th2 cells, resulting in long-term suppression of GVHD. Most of the human B cells detected in the transplanted mice had a plasmablast phenotype. Vaccination with HER2 multiple antigen peptide (CH401MAP or keyhole limpet hemocyanin (KLH successfully induced antigen-specific IgG production in PBMC-transplanted NOG-hIL-4-Tg. The HLA haplotype of donor PBMCs might not be relevant to the antibody secretion ability after immunization. These results suggest that the human PBMC-transplanted NOG-hIL-4-Tg mouse is an effective tool to evaluate the production of antigen-specific IgG antibodies.

  18. SU-D-204-07: Comparison of AAPM TG150 Draft Image Receptor Tests with Vendor Automated QC Tests for Five Mobile DR Units

    Energy Technology Data Exchange (ETDEWEB)

    Li, G; Nishino, T [UT MD Anderson Cancer Center, Houston, TX (United States); Greene, T [Radiation Services, Inc., Dover, FL (United States); Willis, C [MD Anderson Cancer Center, Bellaire, TX (United States)

    2015-06-15

    Purpose: To determine the consistency of digital detector (DR) tests recommended by AAPM TG150 and tests provided by commercially available DirectView Total Quality Tool (TQT). Methods: The DR tests recommended by the TG150 Detector Subgroup[1] were performed on 4 new Carestream DRX-Revolution and one Carestream DRX1C retrofit of a GE AMX-4 that had been in service for three years. After detector calibration, flat-field images plus images of two bar patterns oriented parallel and perpendicular to the A-C axis, were acquired at conditions recommended by TG150. Raw images were harvested and then analyzed using a MATLAB software previously validated[2,3,4]. Data were analyzed using ROIs of two different dimensions: 1) 128 x 128 ROIs matching the detector electronics; and 2) 256 x 256 ROIs, each including 4 adjacent smaller ROIs. TG150 metrics from 128 x 128 ROIs were compared to TQT metrics, which are also obtained from 128 x 128 ROIs[5]. Results: The results show that both TG150 and TQT measurements were consistent among these detectors. Differences between TG150 and TQT values appear systematic. Compared with 128 x 128 ROIs, noise and SNR non-uniformity were lower with 256 x 256 ROIs, although signal non-uniformity was similar, indicating detectors were appropriately calibrated for gain and offset. MTF of the retrofit unit remained essentially the same between 2012 and 2015, but was inferior to the new units. The older generator focal spot is smaller (0.75mm vs. 1.2mm), and the SID for acquisition is 182cm as well, so focal spot dimensions cannot explain the difference. The difference in MTF may be secondary to differences in generator X-ray spectrum or by unannounced changes in detector architecture. Further investigation is needed. Conclusion: The study shows that both TG150 and TQT tests are consistent. The numerical value of some metrics are dependent on ROI size.

  19. SU-F-T-485: Independent Remote Audits for TG51 NonCompliant Photon Beams Performed by the IROC Houston QA Center

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, P; Molineu, A; Lowenstein, J; Taylor, P; Kry, S; Followill, D [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: IROC-H conducts external audits for output check verification of photon and electron beams. Many of these beams can meet the geometric requirements of the TG 51 calibration protocol. For those photon beams that are non TG 51 compliant like Elekta GammaKnife, Accuray CyberKnife and TomoTherapy, IROC-H has specific audit tools to monitor the reference calibration. Methods: IROC-H used its TLD and OSLD remote monitoring systems to verify the output of machines with TG 51 non compliant beams. Acrylic OSLD miniphantoms are used for the CyberKnife. Special TLD phantoms are used for TomoTherapy and GammaKnife machines to accommodate the specific geometry of each machine. These remote audit tools are sent to institutions to be irradiated and returned to IROC-H for analysis. Results: The average IROC-H/institution ratios for 480 GammaKnife, 660 CyberKnife and 907 rotational TomoTherapy beams are 1.000±0.021, 1.008±0.019, 0.974±0.023, respectively. In the particular case of TomoTherapy, the overall ratio is 0.977±0.022 for HD units. The standard deviations of all results are consistent with values determined for TG 51 compliant photon beams. These ratios have shown some changes compared to values presented in 2008. The GammaKnife results were corrected by an experimentally determined scatter factor of 1.025 in 2013. The TomoTherapy helical beam results are now from a rotational beam whereas in 2008 the results were from a static beam. The decision to change modality was based on recommendations from the users. Conclusion: External audits of beam outputs is a valuable tool to confirm the calibrations of photon beams regardless of whether the machine is TG 51 or TG 51 non compliant. The difference found for TomoTherapy units is under investigation. This investigation was supported by IROC grant CA180803 awarded by the NCI.

  20. SU-F-T-485: Independent Remote Audits for TG51 NonCompliant Photon Beams Performed by the IROC Houston QA Center

    International Nuclear Information System (INIS)

    Alvarez, P; Molineu, A; Lowenstein, J; Taylor, P; Kry, S; Followill, D

    2016-01-01

    Purpose: IROC-H conducts external audits for output check verification of photon and electron beams. Many of these beams can meet the geometric requirements of the TG 51 calibration protocol. For those photon beams that are non TG 51 compliant like Elekta GammaKnife, Accuray CyberKnife and TomoTherapy, IROC-H has specific audit tools to monitor the reference calibration. Methods: IROC-H used its TLD and OSLD remote monitoring systems to verify the output of machines with TG 51 non compliant beams. Acrylic OSLD miniphantoms are used for the CyberKnife. Special TLD phantoms are used for TomoTherapy and GammaKnife machines to accommodate the specific geometry of each machine. These remote audit tools are sent to institutions to be irradiated and returned to IROC-H for analysis. Results: The average IROC-H/institution ratios for 480 GammaKnife, 660 CyberKnife and 907 rotational TomoTherapy beams are 1.000±0.021, 1.008±0.019, 0.974±0.023, respectively. In the particular case of TomoTherapy, the overall ratio is 0.977±0.022 for HD units. The standard deviations of all results are consistent with values determined for TG 51 compliant photon beams. These ratios have shown some changes compared to values presented in 2008. The GammaKnife results were corrected by an experimentally determined scatter factor of 1.025 in 2013. The TomoTherapy helical beam results are now from a rotational beam whereas in 2008 the results were from a static beam. The decision to change modality was based on recommendations from the users. Conclusion: External audits of beam outputs is a valuable tool to confirm the calibrations of photon beams regardless of whether the machine is TG 51 or TG 51 non compliant. The difference found for TomoTherapy units is under investigation. This investigation was supported by IROC grant CA180803 awarded by the NCI

  1. A facile method to synthesize nitrogen and fluorine co-doped TiO2 nanoparticles by pyrolysis of (NH4)2TiF6

    International Nuclear Information System (INIS)

    Chen Daimei; Jiang Zhongyi; Geng Jiaqing; Zhu Juhong; Yang Dong

    2009-01-01

    The nitrogen and fluorine co-doped TiO 2 (N-F-TiO 2 ) nanoparticles of anatase crystalline structure were prepared by a facile method of (NH 4 ) 2 TiF 6 pyrolysis, and characterized by thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet visible (UV-Vis) spectroscopy etc. With the increase of calcination temperature, (NH 4 ) 2 TiF 6 decomposed into TiOF 2 and NH 4 TiOF 3 at first, and then formed anatase-type TiO 2 with thin sheet morphology. H 3 BO 3 as oxygen source can promote the formation of anatase TiO 2 , but decrease the F content in the N-F-TiO 2 materials due to the formation of volatile BF 3 during the precursor decomposition. The photocatalytic activity of the obtained N-F-TiO 2 samples was evaluated by the methylene blue degradation under visible light, and all the samples exhibited much higher photocatalytic activity than P25. Moreover, the merits and disadvantages of this proposed method to prepare doped TiO 2 are discussed.

  2. Biodegradability and aging study of rubber films obtained by gamma radiation vulcanization processes of latex

    International Nuclear Information System (INIS)

    Martins, Carlos Felipe Pinto

    2005-01-01

    The natural rubber latex (NRL) is industrially crosslinked by the conventional process of vulcanization, which uses sulphur and heat. Otherwise, the network can also be done by the alternative process with ionizing radiation. In this work the crosslinking of NRL was studied by the comparison of the conventional vulcanization system and the ionizing radiation process of 60 C source. The products obtained, the irradiated latex, the irradiated latex with approximately 1% of soy lecithin and the sulphur vulcanized latex were tested by accelerated aging with ultraviolet (UV) and outdoor aging with compostage, tensile strength at break, swelling and gel fraction, fungi micro biota, scanning electron microscopy (SEM), infrared spectroscopy (FTIR) and thermogravimetry and differential scanning calorimetry analysis (TG and DSC). The results showed that the aging with microorganisms have a great influence in the physical properties of the samples. The thermal stability order observed showed that the sulphur vulcanized latex is more resistant, what is probably associated to a network more stable under the aging conditions. On the other hand, the irradiated latex showed intense biodegradation aspects, particularly with the presence of the soy lecithin. (author)

  3. Antimicrobial coatings based on zinc oxide and orange oil for improved bioactive wound dressings and other applications.

    Science.gov (United States)

    Rădulescu, Marius; Andronescu, Ecaterina; Cirja, Andreea; Holban, Alina Maria; Mogoantă, LaurenŢiu; Bălşeanu, Tudor Adrian; Cătălin, Bogdan; Neagu, Tiberiu Paul; Lascăr, Ioan; Florea, Denisa Alexandra; Grumezescu, Alexandru Mihai; Ciubuca, Bianca; Lazăr, Veronica; Chifiriuc, Mariana Carmen; Bolocan, Alexandra

    2016-01-01

    This work presents a novel nano-modified coating for wound dressings and other medical devices with anti-infective properties, based on functionalized zinc oxide nanostructures and orange oil (ZnO@OO). The obtained nanosurfaces were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), selected area electron diffraction (SAED), differential thermal analysis-thermogravimetry (DTA-TG), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy. The obtained nanocomposite coatings exhibited an antimicrobial activity superior to bare ZnO nanoparticles (NPs) and to the control antibiotic against Staphylococcus aureus and Escherichia coli, as revealed by the lower minimal inhibitory concentration values. For the quantitative measurement of biofilm-embedded microbial cells, a culture-based, viable cell count method was used. The coated wound dressings proved to be more resistant to S. aureus microbial colonization and biofilm formation compared to the uncoated controls. These results, correlated with the good in vivo biodistribution open new directions for the design of nanostructured bioactive coating and surfaces, which can find applications in the medical field, for obtaining improved bioactive wound dressings and prosthetic devices, but also in food packaging and cosmetic industry.

  4. Photo-degradation of CT-DNA with a series of carbothioamide ruthenium (II) complexes - Synthesis and structural analysis

    Science.gov (United States)

    Muthuraj, V.; Umadevi, M.

    2018-04-01

    The present research article is related with the method of preparation, structure and spectroscopic properties of a series of carbothioamide ruthenium (II) complexes with N and S donor ligands namely, 2-((6-chloro-4-oxo-4H-chromen-3-yl)methylene) hydrazine carbothioamide (ClChrTs)/2-((6-methoxy-4-oxo-4H-chromen-3-yl)methylene)hydrazine carbothioamide (MeOChrTS). The synthesized complexes were characterized by several techniques using analytical methods as well as by spectral techniques such as FT-IR, 1HNMR, 13CNMR, ESI mass and thermogravimetry/differential thermal analysis (TG-DTA). The IR spectra shows that the ligand acts as a neutral bidentate with N and S donor atoms. The biological activity of the prepared compounds and metal complexes were tested against cell line of calf-thymus DNA via an intercalation mechanism (MCF-7). In addition, the interaction of Ru(II) complexes and its free ligands with CT-DNA were also investigated by titration with UV-Vis spectra, fluorescence spectra, and Circular dichroism studies. Results suggest that both of the two Ru(II) complexes can bind with calf-thymus DNA via an intercalation mechanism.

  5. Preparation, quantitative surface analysis, intercalation characteristics and industrial implications of low temperature expandable graphite

    Science.gov (United States)

    Peng, Tiefeng; Liu, Bin; Gao, Xuechao; Luo, Liqun; Sun, Hongjuan

    2018-06-01

    Expandable graphite is widely used as a new functional carbon material, especially as fire-retardant; however, its practical application is limited due to the high expansion temperature. In this work, preparation process of low temperature and highly expandable graphite was studied, using natural flake graphite as raw material and KMnO4/HClO4/NH4NO3 as oxidative intercalations. The structure, morphology, functional groups and thermal properties were characterized during expanding process by Fourier transform infrared spectroscopy (FTIR), Raman spectra, thermo-gravimetry differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscope (SEM). The analysis showed that by oxidation intercalation, some oxygen-containing groups were grafted on the edge and within the graphite layer. The intercalation reagent entered the graphite layer to increase the interlayer spacing. After expansion, the original flaky expandable graphite was completely transformed into worm-like expanded graphite. The order of graphite intercalation compounds (GICs) was proposed and determined to be 3 for the prepared expandable graphite, based on quantitative XRD peak analysis. Meanwhile, the detailed intercalation mechanisms were also proposed. The comprehensive investigation paved a benchmark for the industrial application of such sulfur-free expanded graphite.

  6. Photooxidation behaviour of HMS-PP

    International Nuclear Information System (INIS)

    Oliani, Washington L.; Parra, Duclerc F.; Lima, Luis F.C.P.; Lugao, Ademar B.

    2009-01-01

    The radiation process has played an important role to produce polymers with controlled rheological properties. The main scope of the study is to evaluate the stability of High melt strength polypropylene (HMS-PP) prepared by gamma irradiation of PP (spheres) under acetylene atmosphere followed by a heating step to terminate reactions, in different doses of 12.5 kGy and 20 kGy. The samples submitted to the natural ageing for a period of one year were characterized by: thermogravimetry (TG), differential scanning calorimetry (DSC), infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The fundamental process that is believed to be the most significant in the mechanism of photooxidative degradation is the formation of hydroperoxides. The high energy UV light is capable of initiating bond scission within the polymer backbone, which leads to further chemical modification of the bonds via scissions and chain reactions through formation of radical species. The results showed that in pristine and HMS-PP samples exposed to UV radiation, oxidation reactions occur, resulting in chain scissions. The reactions occur preferentially in the amorphous phase owing to the higher permeability of oxygen. (author)

  7. Characterization of Iron and Steel Industry Slags to be Recycled under Ecological Aspects as a Recycling Concept for Waste Treatment

    International Nuclear Information System (INIS)

    Khalil, T.K.; Aly, H.F.; Bossert, J.

    1999-01-01

    The recycling and final disposal of different types of industrial waste play an important role in decreasing environmental pollution all over the world. Three different solid waste slags from steel industries situated in the Helwan area (Cairo-Egypt), namely blast furnace slags, oxygen converter slags arc furnace slags were studied. The morphology of the collected slag powders was examined using scanning electron microscopy (SEM). Surface characteristics of the slag powders were measured through nitrogen gas adsorption and application of the BET equation at 77 K. The thermal behaviour of the slag powders was studied with the help of differential thermal analysis (DTA) and thermogravimetry(TG)> Due to the presence of some changes in the DTA base lines, possibly as a result of phase transformations, X-ray diffraction was applied to identify these phases. The sintering behaviour of the compact slag powders after isostatic pressing was evaluated using dilatometry. The sintering and melting temperature of the studied samples were determined using heating microscopy. The effect of changing sintering temperature and of applying different isostatic pressures on the density and porosity of the slag powder compacts was investigated

  8. Risperidone – Solid-state characterization and pharmaceutical compatibility using thermal and non-thermal techniques

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Josiane Souza Pereira; Veronez, Isabela Pianna; Rodrigues, Larissa Lopes [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); Trevisan, Marcello G. [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil); National Institute of Bioanalytics Science and Technology – INCTBio, Institute of Chemistry – UNICAMP, 13084-653, Campinas, São Paulo (Brazil); Garcia, Jerusa Simone, E-mail: jerusa.garcia@unifal-mg.edu.br [Laboratório de Análise e Caracterização de Fármacos – LACFar, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Minas Gerais (Brazil)

    2013-09-20

    Highlights: • DSC was used to characterize Risperidone and study its compatibility with excipients. • FT-IR associated with PCA was used to complement DSC data. • LC analyzes confirmed the DSC and FT-IR/PCA results. • Risperidone was incompatible with three among five excipients evaluated. - Abstract: A full solid-state characterization of risperidone was conducted using differential scanning calorimetry (DSC), thermogravimetry (TG), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) to examine its physicochemical properties and polymorphism. The primary aim of this work was to study the compatibility of risperidone with pharmaceutical excipients using DSC to obtain and compare the curves of the active pharmaceutical ingredient (API) and the excipients with their 1:1 (w/w) binary mixtures. These same binary mixtures were turned to room temperature and analyzed by FT-IR combined with principal component analysis (PCA) to evaluate solid-state incompatibilities. The chemical incompatibilities of these samples were verified using a stability-indicating liquid chromatography (LC) method to assay for the API and evaluate the formation of degradation products. All of these methods showed incompatibilities between risperidone and the excipients magnesium stearate, lactose and cellulose microcrystalline.

  9. Process development and characterization of centrosymmetric semiorganic nonlinear optical crystal: 4-dimethylaminopyridine potassium chloride

    Science.gov (United States)

    Johnson, J.; Srineevasan, R.; Sivavishnu, D.

    2018-06-01

    Centrosymmetric semiorganic crystal 4-dimethylaminopyridine potassium chloride (4-DMAPKC) has been grown successfully by using slow evaporation solution growth technique. Powder x-ray diffraction shows the 4-DMAPKC crystal has good crystalline nature. Single crystal XRD shows that the grown 4-DMAPKC is cubic crystal system with cell parameters a = 3.09 Å, b = 3.09 Å, c = 3.09 Å. Investigation has been carried out to assign the Vibrational frequencies of the grown crystal by FTIR spectral studies. UVsbnd Visible NIR optical absorption spectral studies in the range of 200-1100 nm shows low absorption in UVsbnd Visible region with lower cutoff wave length at 261 nm and optical band gap energy was found as Eg = 5.52 eV. Optically transmittance spectral shows 4-DMAPKC crystal is very good transparency in UV-Visible NIR region. Thermogravimetry and differential thermal (TG-DTA) analysis were carried out. Dielectric studies of as grown crystal sample exhibit low dielectric constant and loss at higher frequencies and attests the nonlinear optical activity. Micro hardness studies of as grown crystal were discussed. Second harmonic generation (SHG) efficiency of the 4-DMAPKC is 0.69 times as that of KDP.

  10. Biodegradability and aging study of rubber films obtained by gamma radiation vulcanization processes of latex; Estudo da biodegradabilidade e envelhecimento de filmes de borracha obtidos por processos de vulcanizacao do latex por radiacao induzida de fonte gama

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Carlos Felipe Pinto

    2005-07-01

    The natural rubber latex (NRL) is industrially crosslinked by the conventional process of vulcanization, which uses sulphur and heat. Otherwise, the network can also be done by the alternative process with ionizing radiation. In this work the crosslinking of NRL was studied by the comparison of the conventional vulcanization system and the ionizing radiation process of {sup 60}C source. The products obtained, the irradiated latex, the irradiated latex with approximately 1% of soy lecithin and the sulphur vulcanized latex were tested by accelerated aging with ultraviolet (UV) and outdoor aging with compostage, tensile strength at break, swelling and gel fraction, fungi micro biota, scanning electron microscopy (SEM), infrared spectroscopy (FTIR) and thermogravimetry and differential scanning calorimetry analysis (TG and DSC). The results showed that the aging with microorganisms have a great influence in the physical properties of the samples. The thermal stability order observed showed that the sulphur vulcanized latex is more resistant, what is probably associated to a network more stable under the aging conditions. On the other hand, the irradiated latex showed intense biodegradation aspects, particularly with the presence of the soy lecithin. (author)

  11. Nanomaterial Host Bands Effect on the Photoluminescence Properties of Ce-Doped YAG Nanophosphor Synthesized by Sol-Gel Method

    Directory of Open Access Journals (Sweden)

    L. Guerbous

    2015-01-01

    Full Text Available Cerium trivalent (Ce3+ doped YAG nano-sized phosphors have been successfully synthesized by sol-gel method using different annealing temperatures. The samples have been characterized by X-ray diffraction (XRD, thermogravimetry (TG, differential scanning calorimetry (DSC analysis, Fourier transform infrared (FTIR spectroscopy, and steady photoluminescence (PL spectroscopy. X-ray diffraction analysis indicates that the pure cubic phase YAG was formed and strongly depends on the cerium content and the annealing temperature. It was found that the grain size ranges from 30 to 58 nm depending on the calcination temperature. The YAG: Ce nanophosphors showed intense, green-yellow emission, corresponding to Ce3+ 5d1→2F5/2, 2F7/2 transitions and its photoluminescence excitation spectrum contains the two Ce3+ 4f1→5d1, 5d2 bands. The crystal filed splitting energy levels positions 5d1 and 5d2 and the emission transitions blue shift with annealing temperatures have been discussed. It was found that the Ce3+ 4f1 ground state position relative to valence band maximum of YAG host nanomaterial decreases with increasing the temperature.

  12. A pH-, salt- and solvent-responsive carboxymethylcellulose-g-poly(sodium acrylate/medical stone superabsorbent composite with enhanced swelling and responsive properties

    Directory of Open Access Journals (Sweden)

    2011-05-01

    Full Text Available Free-radical graft copolymerization among sodium carboxymethylcellulose (CMC, partially neutralized acrylic acid (NaA, medical stone (MS and crosslinker N,N'-methylene-bis-acrylamide (MBA was performed to prepare new carboxymethylcellulose-g-poly(sodium acrylate/medical stone (CMC-g-PNaA/MS superabsorbent composites. Fourier transform infrared (FTIR spectra, thermogravimetry- differential scanning calorimetry (TG-DSC and field emission scanning electromicrsocopic (FESEM analysis confirmed that NaA had been grafted onto CMC backbone and MS participated in polymerization, and the thermal stability and surface morphologies were improved by the addition of MS. Energy dispersive spectrometer (EDS and elemental map (EM analyses revealed the better distribution of MS in the CMC-g-PNaA matrix. The incorporation of 20 wt% MS clearly enhanced the water absorption by 100% (from 317 to 634 g/g. The developed composites showed enhanced swelling rate and On-Off switching swelling characteristics in various pH solutions, saline solutions and hydrophilic organic solvents, which represented interesting and reversible pH-, saline- and hydrophilic organic solvent-responsive characteristics. In addition, the composite exhibited intriguing time-dependent kinetic swelling properties in various heavy metal solutions.

  13. Effect of ionizing radiation on mechanical and thermal properties of low-density polyethylene containing pro-degradant agents

    International Nuclear Information System (INIS)

    Bardi, Marcelo A.G.; Kodama, Yasko; Machado, Luci D.B.; Giovedi, Claudia; Rosa, Derval S.

    2009-01-01

    The wide use of plastics on packages of short-lifetime products has presented harmful consequences for the environment due to their low degradation rate. By this way, improved results to the bio-assimilation of polyolefins have been achieved by the incorporation of pro-oxidant components. The aim of this work is to evaluate the mechanical and thermal behavior of low-density polyethylene (LDPE) modified by those agents and submitted to ionizing radiation by gamma rays. LDPE was modified using a masterbatch containing calcium stearate (CaSt), or magnesium stearate (MgSt) or Clariant R commercial metallic complex. The final amount of stearate in modified LDPE was 0.2%. The films were obtained by compression molding. Samples were gamma irradiated at absorbed doses of 15 kGy and 100 kGy. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were performed on samples, as well as mechanical analysis by universal testing machine. Thermal properties of samples presenting pro-degradant agents were affected by the ionizing radiation in the dose range studied, and some of the mechanical properties were clearly modified by reducing their values of tensile strength at break and elongation at break. (author)

  14. Effect of ionizing radiation on mechanical and thermal properties of low-density polyethylene containing pro-degradant agents

    Energy Technology Data Exchange (ETDEWEB)

    Bardi, Marcelo A.G.; Kodama, Yasko; Machado, Luci D.B., E-mail: magbardi@ipen.b, E-mail: ykodama@ipen.b, E-mail: lmachado@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Giovedi, Claudia, E-mail: giovedi@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil); Rosa, Derval S., E-mail: derval.rosa@ufabc.edu.b [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil)

    2009-07-01

    The wide use of plastics on packages of short-lifetime products has presented harmful consequences for the environment due to their low degradation rate. By this way, improved results to the bio-assimilation of polyolefins have been achieved by the incorporation of pro-oxidant components. The aim of this work is to evaluate the mechanical and thermal behavior of low-density polyethylene (LDPE) modified by those agents and submitted to ionizing radiation by gamma rays. LDPE was modified using a masterbatch containing calcium stearate (CaSt), or magnesium stearate (MgSt) or Clariant{sup R} commercial metallic complex. The final amount of stearate in modified LDPE was 0.2%. The films were obtained by compression molding. Samples were gamma irradiated at absorbed doses of 15 kGy and 100 kGy. Differential scanning calorimetry (DSC) and thermogravimetry (TG) were performed on samples, as well as mechanical analysis by universal testing machine. Thermal properties of samples presenting pro-degradant agents were affected by the ionizing radiation in the dose range studied, and some of the mechanical properties were clearly modified by reducing their values of tensile strength at break and elongation at break. (author)

  15. Post irradiation effects on the graft of poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) films

    International Nuclear Information System (INIS)

    Geraldes, Adriana N.; Zen, Heloisa A.; Ribeiro, Geise; Ferreira, Henrique P.; Souza, Camila P.; Parra, Duclerc F.; Lugao, Ademar B.

    2009-01-01

    Radiation induced grafting of monomers into fluorinated polymers was designed as an alternative route to polymer modification. In this work, grafting of styrene onto poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) was studied. Radiation-induced grafting of styrene onto PFA films was investigated after simultaneous irradiation (in post-irradiation condition) using a 60 Co source. The films of PFA were irradiated at 20, 40, 80 and 100 kGy doses at room temperature and chemical changes were monitored after contact with styrene for grafting. The post-irradiation time was established between 7 and 28 days when films of PFA were maintained in styrene/toluene 1:1 v/v solution at room temperature. After these periods the grafting degrees were evaluated in the samples. The highest degree of grafting was achieved after 14 days. Chemical modifications were evaluated by infrared spectroscopic analysis (FTIR), thermogravimetry (TG), differential scanning calorimetry (DSC) and also by scanning electron microscopy (SEM). The degree of grafting (DOG) was determined gravimetrically. The results showed that irradiated PFA films at 100 kGy exhibited higher grafting degree. Surface analysis by SEM technique of irradiated, grafted and original films have presented an homogeneous surface. (author)

  16. Detection of compatibility between baclofen and excipients with aid of infrared spectroscopy and chemometry.

    Science.gov (United States)

    Rojek, Barbara; Wesolowski, Marek; Suchacz, Bogdan

    2013-12-01

    In the paper infrared (IR) spectroscopy and multivariate exploration techniques: principal component analysis (PCA) and cluster analysis (CA) were applied as supportive methods for the detection of physicochemical incompatibilities between baclofen and excipients. In the course of research, the most useful rotational strategy in PCA proved to be varimax normalized, while in CA Ward's hierarchical agglomeration with Euclidean distance measure enabled to yield the most interpretable results. Chemometrical calculations confirmed the suitability of PCA and CA as the auxiliary methods for interpretation of infrared spectra in order to recognize whether compatibilities or incompatibilities between active substance and excipients occur. On the basis of IR spectra and the results of PCA and CA it was possible to demonstrate that the presence of lactose, β-cyclodextrin and meglumine in binary mixtures produce interactions with baclofen. The results were verified using differential scanning calorimetry, differential thermal analysis, thermogravimetry/differential thermogravimetry and X-ray powder diffraction analyses. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Association of peripheral differential leukocyte counts with dyslipidemia risk in Chinese patients with hypertension: insight from the China Stroke Primary Prevention Trial.

    Science.gov (United States)

    Liu, Yanhong; Kong, Xiangyi; Wang, Wen; Fan, Fangfang; Zhang, Yan; Zhao, Min; Wang, Yi; Wang, Yupeng; Wang, Yu; Qin, Xianhui; Tang, Genfu; Wang, Binyan; Xu, Xiping; Hou, Fan Fan; Gao, Wei; Sun, Ningling; Li, Jianping; Venners, Scott A; Jiang, Shanqun; Huo, Yong

    2017-01-01

    The aim of the present study was to examine the association between peripheral differential leukocyte counts and dyslipidemia in a Chinese hypertensive population. A total of 10,866 patients with hypertension were enrolled for a comprehensive assessment of cardiovascular risk factors using data from the China Stroke Primary Prevention Trial. Plasma lipid levels and total leukocyte, neutrophil, and lymphocyte counts were determined according to standard methods. Peripheral differential leukocyte counts were consistently and positively associated with serum total cholesterol (TC), LDL cholesterol (LDL-C), and TG levels (all P dyslipidemia/normolipidemia), we found that patients in the highest quartile of total leukocyte count (≥7.6 × 10 9 cells/l) had 1.64 times the risk of high TG [95% confidence interval (CI): 1.46, 1.85], 1.34 times the risk of high TC (95% CI: 1.20, 1.50), and 1.24 times the risk of high LDL-C (95% CI: 1.12, 1.39) compared with their counterparts in the lowest quartile of total leukocyte count. Similar patterns were also observed with neutrophils and lymphocytes. In summary, these findings indicate that elevated differential leukocyte counts are directly associated with serum lipid levels and increased odds of dyslipidemia. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  18. Brief Eclectic Psychotherapy for Traumatic Grief (BEP-TG): toward integrated treatment of symptoms related to traumatic loss.

    Science.gov (United States)

    Smid, Geert E; Kleber, Rolf J; de la Rie, Simone M; Bos, Jannetta B A; Gersons, Berthold P R; Boelen, Paul A

    2015-01-01

    Traumatic events such as disasters, accidents, war, or criminal violence are often accompanied by the loss of loved ones, and may then give rise to traumatic grief. Traumatic grief refers to a clinical diagnosis of persistent complex bereavement disorder (PCBD) with comorbid (symptoms of) posttraumatic stress disorder (PTSD) and/or major depressive disorder (MDD) following confrontation with a traumatic loss. Trauma survivors, who are frequently from different cultural backgrounds, have often experienced multiple losses and ambiguous loss (missing family members or friends). Current evidence-based treatments for PTSD do not focus on traumatic grief. To develop a treatment for traumatic grief combining treatment interventions for PTSD and PCBD that may accommodate cultural aspects of grief. To provide a rationale for treatment, we propose a cognitive stress model of traumatic grief. Based on this model and on existing evidence-based treatments for PTSD and complicated grief, we developed Brief Eclectic Psychotherapy for Traumatic Grief (BEP-TG) for the treatment of patients with traumatic grief. The treatment is presented along with a case vignette. Processes contributing to traumatic grief include inadequately integrating the memory of the traumatic loss, negative appraisal of the traumatic loss, sensitivity to matching triggers and new stressors, and attempting to avoid distress. BEP-TG targets these processes. The BEP-TG protocol consists of five parts with proven effectiveness in the treatment of PCBD, PTSD, and MDD: information and motivation, grief-focused exposure, memorabilia and writing assignments, finding meaning and activation, and a farewell ritual. Tailored to fit the needs of trauma survivors, BEP-TG can be used to address traumatic grief symptoms related to multiple losses and ambiguous loss, as well as cultural aspects of bereavement through its different components.

  19. Developing a Treatment Planning Software Based on TG-43U1 Formalism for Cs-137 LDR Brachytherapy.

    Science.gov (United States)

    Sina, Sedigheh; Faghihi, Reza; Soleimani Meigooni, Ali; Siavashpour, Zahra; Mosleh-Shirazi, Mohammad Amin

    2013-08-01

    The old Treatment Planning Systems (TPSs) used for intracavitary brachytherapy with Cs-137 Selectron source utilize traditional dose calculation methods, considering each source as a point source. Using such methods introduces significant errors in dose estimation. As of 1995, TG-43 is used as the main dose calculation formalism in treatment TPSs. The purpose of this study is to design and establish a treatment planning software for Cs-137 Solectron brachytherapy source, based on TG-43U1 formalism by applying the effects of the applicator and dummy spacers. Two softwares used for treatment planning of Cs-137 sources in Iran (STPS and PLATO), are based on old formalisms. The purpose of this work is to establish and develop a TPS for Selectron source based on TG-43 formalism. In this planning system, the dosimetry parameters of each pellet in different places inside applicators were obtained by MCNP4c code. Then the dose distribution around every combination of active and inactive pellets was obtained by summing the doses. The accuracy of this algorithm was checked by comparing its results for special combination of active and inactive pellets with MC simulations. Finally, the uncertainty of old dose calculation formalism was investigated by comparing the results of STPS and PLATO softwares with those obtained by the new algorithm. For a typical arrangement of 10 active pellets in the applicator, the percentage difference between doses obtained by the new algorithm at 1cm distance from the tip of the applicator and those obtained by old formalisms is about 30%, while the difference between the results of MCNP and the new algorithm is less than 5%. According to the results, the old dosimetry formalisms, overestimate the dose especially towards the applicator's tip. While the TG-43U1 based software perform the calculations more accurately.

  20. Total skin high-dose-rate electron therapy dosimetry using TG-51

    International Nuclear Information System (INIS)

    Gossman, Michael S.; Sharma, Subhash C.

    2004-01-01

    An approach to dosimetry for total skin electron therapy (TSET) is discussed using the currently accepted TG-51 high-energy calibration protocol. The methodology incorporates water phantom data for absolute calibration and plastic phantom data for efficient reference dosimetry. The scheme is simplified to include the high-dose-rate mode conversion and provides support for its use, as it becomes more available on newer linear accelerators. Using a 6-field, modified Stanford technique, one may follow the process for accurate determination of absorbed dose

  1. License - Open TG-GATEs | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us Open TG-GATEs License License to Use This Database Last updated : 2012/05/24 You may use this database...scribed below. The Standard License specifies the license terms regarding the use of this database and the r...equirements you must follow in using this database. The Additional License specif...icense. Standard License The Standard License for this database is the license specified in the Creative Com...mons Attribution-Share Alike 2.1 Japan . If you use data from this database, plea

  2. Micromechanical thermogravimetry

    Science.gov (United States)

    Berger, R.; Lang, H. P.; Gerber, Ch.; Gimzewski, J. K.; Fabian, J. H.; Scandella, L.; Meyer, E.; Güntherodt, H.-J.

    1998-09-01

    We demonstrate a new method for thermal analysis of nanogram quantities of material using a micromechanical thermogravimetric technique. The cantilever-type device uses an integrated piezoresistor to sense bending and simultaneously to ramp the temperature and control temperature cycles. It has a mass resolution in the picogram range. A quantitative analysis of the dehydration of copper-sulfate-pentahydrate (CuSO 4·5H 2O) is presented. The technique outperforms current thermogravimetric approaches by five orders of magnitude.

  3. Role of protein glycosylation on the expression of muscarinic receptors of N4TG1 neuroblastoma cells

    International Nuclear Information System (INIS)

    Ahmad, A.; Chiang, P.K.

    1986-01-01

    Muscarinic acetylcholine receptors (mAChR) are glycoproteins. Experiments were conducted to determine whether active glycosylation of proteins in N4TG1 neuroblastoma cells could affect the expression of muscarinic receptors on the cell surface. The binding of radioactive N-methylscopolamine, a membrane impermeable ligand, to intact cells was used as a measure of mAChR. In the presence of the inhibitors of glycosylation, such as tunicamycin, monensin and amphomycin, N-linked glycosylation of proteins in the N4TG1 cells was inhibited, as measured by the incorporation of radioactive glucosamine or mannose in proteins. At the concentrations of tunicamycin and monensin used, the glycosylation of proteins after 3 hours were drastically reduced, but the number of mAChR in the cells was not altered. The apparent lack of effect within a short incubation period could be attributed to the presence of preformed oligosaccharide dolichol readily available for N-glycosylation. However, after 24 hours, tunicamycin (0.05 μg/ml) caused a decrease in the number of mAChR by 17% without having any effect on protein synthesis. Therefore, de novo glycosylation of proteins may be required for the expression of mAChR receptors in the N4TG1 neuroblastoma cell surface

  4. Thermal and mechanical properties of polyamide 6/compatibilizer/clay nano composites

    International Nuclear Information System (INIS)

    Agrawal, P.; Brito, G.F.; Cunha, C.T.C.; Araujo, E.M.; Melo, T.J.A.

    2010-01-01

    In this work, the thermal and mechanical properties of Polyamide 6 (PA6)/compatibilizer/clay (CL20A) nanocomposites were investigated. The nanocomposites were prepared in a counter-rotating twin screw extruder at 240 deg C and 50 rpm, and characterized by X-Ray Diffraction (XRD), Thermogravimetry (TG) and mechanical properties. XRD results showed that when the clay is mixed with PA6, the clay peak is shifted to lower 2θ angles, indicating that PA6 was intercalated between the clay platelets. For PA6/compatibilizer/clay system, the results indicated that a nanocomposite with exfoliated structure was formed. TG results showed that the thermal stability of PA6/CL20A and PA6/compatibilizer/CL20A was higher than that of neat PA6. The mechanical properties results showed that the addition of the compatibilizer to PA6/CL20A substantially increased the impact strength and decreased the stiffness. (author)

  5. Positive periodic solutions of neutral functional differential equations with a parameter and impulse

    Directory of Open Access Journals (Sweden)

    Xuanlong Fan

    2008-03-01

    Full Text Available In this paper, we consider first-order neutral differential equations with a parameter and impulse in the form of $$displaylines{ frac{d}{dt}[x(t-c x(t-gamma]=-a(tg(x(h_1(tx(t+lambda b(t fig(x(h_2(tig,quad t eq t_j;cr Delta ig[x(t-c x(t-gammaig]=I_jig(x(tig,quad t=t_j,; jinmathbb{Z}^+. }$$ Leggett-Williams fixed point theorem, we prove the existence of three positive periodic solutions.

  6. Thermal decomposition of natural polysaccharides: Chitin and chitosan

    Directory of Open Access Journals (Sweden)

    Kuchina Yu.A.

    2015-03-01

    Full Text Available The results of the thermal analysis of shrimp’s chitin and chitosan have been presented (samples of polysaccharide differed by the deacetylation degree have been studied. The thermal analysis has been carried out by differential thermogravimetry and differential scanning calorimetry. Activation energy of process of chitin and chitosan thermal destruction has been calculated

  7. I-124 PET/CT to Predict the Outcome of Blind I-131 Treatment in Patients with Biochemical Recurrence of Differentiated Thyroid Cancer : Results of a Multicenter Diagnostic Cohort Study (THYROPET)

    NARCIS (Netherlands)

    Kist, Jakob W.; de Keizer, Bart; van der Vlies, Manfred; Brouwers, Adrienne H.; Huysmans, Dyde A.; van der Zant, Friso M.; Hermsen, Rick; Stokkel, Marcel P. M.; Hoekstra, Otto S.; Vogel, Wouter V.

    Patients with suspected recurrence from differentiated thyroid carcinoma, based on an increased thyroglobulin (Tg) level and negative neck ultrasound (US), pose a clinical dilemma. Because standard imaging has a low yield identifying potential recurrence, blind I-131 treatment is often applied.

  8. Timing of post 131I ablation diagnostic whole body scan in differentiated thyroid cancer patients. Less than four months post ablation may be too early.

    Science.gov (United States)

    Winter, M; Winter, J; Heinzel, A; Behrendt, F F; Krohn, T; Mottaghy, F M; Verburg, F A

    2015-01-01

    to determine whether the first three months after 131I ablation is too early to perform radioiodine diagnostic whole body scintigraphy (dxWBS) in differentiated thyroid carcinoma patients. The files of 462 patients who were treated for DTC in our hospital were reviewed. All patients underwent surgical thyroidectomy. 146 patients had data available on a. a dxWBS which was performed less than four months (max 120 days) after 131I ablation with concurrent stimulated TSH stimulated thyroglobulin (Tg) measurement without further therapeutic measures between ablation and dxWBS and b. a second dxWBS or 131I therapy (rxWBS) within 1.5 years after ablation. A discordance between the initial and follow-up scan was found in 25/129 (19%) patients: of 54 patients with a positive initial dxWBS, scan results of a second dxWBS or rxWBS obtained with a suitable distance to the initial scan contradicted the initial one in 15 patients (27%). New lesions were discovered in 10/74 negative first dxWBS cases (14%). A discordance between the initial and follow-up stimulated Tg was found in 5/129 (4%) patients: 2/90 (2%) of patients with a negative stimulated Tg at initial dxWBS subsequently showed a positive results whereas 3/29 (10%) patients with an initially positive Tg showed a negative Tg level at the second procedure. Less than four months after 131I ablation is too early to perform radioiodine diagnostic whole body scintigraphy with concurrent TSH stimulated Tg measurement. The identification of the right, later, timepoint however requires further research.

  9. Immuno-Spin Trapping-Based Detection of Oxidative Modifications in Cardiomyocytes and Coronary Endothelium in the Progression of Heart Failure in Tgαq*44 Mice

    Directory of Open Access Journals (Sweden)

    Bartosz Proniewski

    2018-05-01

    Full Text Available Recent studies suggest both beneficial and detrimental role of increased reactive oxygen species and oxidative stress in heart failure (HF. However, it is not clear at which stage oxidative stress and oxidative modifications occur in the endothelium in relation to cardiomyocytes in non-ischemic HF. Furthermore, most methods used to date to study oxidative stress are either non-specific or require tissue homogenization. In this study, we used immuno-spin trapping (IST technique with fluorescent microscopy-based detection of DMPO nitrone adducts to localize and quantify oxidative modifications of the hearts from Tgαq*44 mice; a murine model of HF driven by cardiomyocyte-specific overexpression of Gαq* protein. Tgαq*44 mice and age-matched FVB controls at early, transition, and late stages of HF progression were injected with DMPO in vivo and analyzed ex vivo for DMPO nitrone adducts signals. Progressive oxidative modifications in cardiomyocytes, as evidenced by the elevation of DMPO nitrone adducts, were detected in hearts from 10- to 16-month-old, but not in 8-month-old Tgαq*44 mice, as compared with age-matched FVB mice. The DMPO nitrone adducts were detected in left and right ventricle, septum, and papillary muscle. Surprisingly, significant elevation of DMPO nitrone adducts was also present in the coronary endothelium both in large arteries and in microcirculation simultaneously, as in cardiomyocytes, starting from 10-month-old Tgαq*44 mice. On the other hand, superoxide production in heart homogenates was elevated already in 6-month-old Tgαq*44 mice and progressively increased to high levels in 14-month-old Tgαq*44 mice, while the enzymatic activity of catalase, glutathione reductase, and glutathione peroxidase was all elevated as early as in 4-month-old Tgαq*44 mice and stayed at a similar level in 14-month-old Tgαq*44. In summary, this study demonstrates that IST represents a unique method that allows to quantify oxidative

  10. Use of high temperature thermogravimetry for the determination of oxidation, reduction, corrosion-type reactions kinetics

    International Nuclear Information System (INIS)

    Benoist, Luc; Bancel, Fabrice; Setaram

    2002-01-01

    Full text.Thermogravimetry is a very powerful technique for the investigation of gas-solid interactions, by measuring the amount of gas adsorbed on the sample or desorbed from the sample. According to the type of interaction, this amount of gas can be very small, that means that the detection of the mass variation can be very difficult to achieve. This is especially the case for certain types of oxidation, reduction and corrosion reactions in the field of metallic and ceramic materials. The good configuration for such kinetic studies is a hanged up sample, to get every face of the sample in contact with the atmosphere. In order to improve the thermogravimetric measurement, two ways can be used: increase the sample mass and especially its area, second use a symmetrical balance. As the gas-solid interaction is adsorption or desorption-type, the area of the sample is one very important parameter. For such a determination, it is important to increase as much as possible this area, that means increasing the sample size and mass. By increasing the contact area for the gas interaction, the accuracy of such a thermogravimetric measurement is largely improved. This design is very convenient for any metallic or ceramic sample that can be directly hung to the balance, without using any container. The second way of improving the test is to use a symmetrical thermogravimetric design. If the variation of mass is too weak to be measured (some micrograms for example), a symmetrical design has to be used. In such a system, a sample and a reference are hung at each beam of the balance, in two identical furnaces. Such a symmetrical technique allows to compensate the buoyancy effect that is identical on both sides. The limit of detection of the thermogravimetric measure is largely improved, allowing accurate measurements on very small variations of mass for long term basis experiments. An example of oxidation of a plate of steel at 500 celsius degree, with a slow mass gain of 1.5

  11. TU-D-201-03: Results of a Survey On the Implementation of the TG-51 Protocol and Associated Addendum On Reference Dosimetry of External Beams

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G [University of California, San Diego, La Jolla, CA (United States); Muir, B [National Research Council, Ottawa, AB (Canada); Culberson, W [University of Wisconsin Madison, Madison, WI (United States); Davis, S [McGill University Health Center, Montreal, QC (Canada); Huang, Y [Henry Ford Health System, West Bloomfield, MI (United States); Lee, S [University of Maryland School of Medicine, Columbia, MD (United States); Lowenstein, J [UT MD Anderson Cancer Center, Houston, TX (United States); Sarfehnia, A [Sunnybrook Health Science Center, Toronto, ON (Canada); Tolani, N [Michael E. DeBakey VA Medical Center, Sugarland (United States); Siebers, J [University of Virginia Health System, Charlottesville, VA (United States)

    2016-06-15

    Purpose: The working group on the review and extension of the TG-51 protocol (WGTG51) collected data from American Association of Physicists in Medicine (AAPM) members with respect to their current TG-51 and associated addendum usage in the interest of considering future protocol addenda and guidance on reference dosimetry best practices. This study reports an overview of this survey on dosimetry of external beams. Methods: Fourteen survey questions were developed by WGTG51 and released in November 2015. The questions collected information on reference dosimetry, beam quality specification, and ancillary calibration equipment. Results: Of the 190 submissions completed worldwide (U.S. 70%), 83% were AAPM members. Of the respondents, 33.5% implemented the TG-51 addendum, with the maximum calibration difference for any photon beam, with respect to the original TG-51 protocol, being <1% for 97.4% of responses. One major finding is that 81.8% of respondents used the same cylindrical ionization chamber for photon and electron dosimetry, implying that many clinics are foregoing the use of parallel-plate chambers. Other evidence suggests equivalent dosimetric results can be obtained with both cylindrical and parallel-plate chambers in electron beams. This, combined with users comfort with cylindrical chambers for electrons will likely impact recommendations put forward in an upcoming electron beam addendum to the TG-51 protocol. Data collected on ancillary equipment showed 58.2% (45.0%) of the thermometers (barometers) in use for beam calibration had NIST traceable calibration certificates, but 48.4% (42.7%) were never recalibrated. Conclusion: This survey provides a snapshot of TG-51 external beam reference dosimetry practice in radiotherapy centers. Findings demonstrate the rapid take-up of the TG-51 photon beam addendum and raise issues for the WGTG51 to focus on going forward, including guidelines on ancillary equipment and the choice of chamber for electron beam

  12. TG101209, a small molecule JAK2-selective kinase inhibitor potently inhibits myeloproliferative disorder-associated JAK2V617F and MPLW515L/K mutations.

    Science.gov (United States)

    Pardanani, A; Hood, J; Lasho, T; Levine, R L; Martin, M B; Noronha, G; Finke, C; Mak, C C; Mesa, R; Zhu, H; Soll, R; Gilliland, D G; Tefferi, A

    2007-08-01

    JAK2V617F and MPLW515L/K represent recently identified mutations in myeloproliferative disorders (MPD) that cause dysregulated JAK-STAT signaling, which is implicated in MPD pathogenesis. We developed TG101209, an orally bioavailable small molecule that potently inhibits JAK2 (IC(50)=6 nM), FLT3 (IC(50)=25 nM) and RET (IC(50)=17 nM) kinases, with significantly less activity against other tyrosine kinases including JAK3 (IC(50)=169 nM). TG101209 inhibited growth of Ba/F3 cells expressing JAK2V617F or MPLW515L mutations with an IC(50) of approximately 200 nM. In a human JAK2V617F-expressing acute myeloid leukemia cell line, TG101209-induced cell cycle arrest and apoptosis, and inhibited phosphorylation of JAK2V617F, STAT5 and STAT3. Therapeutic efficacy of TG101209 was demonstrated in a nude mouse model. Furthermore, TG101209 suppressed growth of hematopoietic colonies from primary progenitor cells harboring JAK2V617F or MPL515 mutations.

  13. Investigation of hydropyrolysis behaviour of Shenmu macerals by TG-MS

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Q.; Li, W.; Chen, H.; Li, B. [Analysis and Test Center, Shandong Academy of Sciences, Jinan (China)

    2004-12-01

    The hydropyrolysis characteristics of Shenmu coal and its macerals were investigated using TG-151 thermo balance, and the evolved gases were on-line analyzed by mass spectroscopy. The results show that vitrinite has higher volatile yield, maximum weight loss rate and lower peak temperature. Vitrinite produces more C{sub 1} - C{sub 4} lighter hydrocarbons and C{sub 5} - C{sub 8} aromatic hydrocarbons than inertinite. Vitrinite has a higher water yield, which is consistent with that the vitrinite has higher phenolic-OH content. The difference in the evolved gases and water between pyrolysis and hydropyrolysis shows the effect of hydrogenation and hydrocracking during hydropyolysis. 11 refs., 4 figs., 1 tab.

  14. Influence of processing parameters on microstructure and tensile properties of TG6 titanium alloy

    International Nuclear Information System (INIS)

    Wang Tao; Guo Hongzhen; Wang Yanwei; Yao Zekun

    2010-01-01

    Research highlights: → This paper highlights the relationships among processing parameters, microstructure and tensile properties of TG6 high temperature titanium alloy. → The microstructural evolutions under different processing parameters were studied by the quantitative metallography, and the effects of microstructure on room and high temperature tensile properties of TG6 alloy were analysed by SEM and TEM. → Linear relationships of elongation vs. volume fraction of primary α phase and ultimate tensile strength vs. thickness of lamellar α phase were determined. - Abstract: Near-isothermal forging of the TG6 titanium alloy was conducted on microprocessor-controlled 630 ton hydraulic press at the deformation temperatures ranging from 850 deg. C to 1045 deg. C, the strain rates of 0.0008 s -1 , 0.003 s -1 and 0.008 s -1 and the deformation degree from 10% to 70%, and then different double heat treatments were applied to the forged specimens. The microstructural evolutions were researched by optical microscope and the microstructural features, i.e. volume fraction of primary α phase and thickness of lamellar α phase, were measured by means of the image analysis software. The room and high temperature tensile properties were obtained for all the specimens. Effects of microstructure on the properties were analysed by scanning electronic microscope. It was found that tenslie properties depended on microstructural features strongly. The plots of ultimate tensile strength vs. thickness of α lamellae and elongation vs. volume fraction of primary α phase produced straight lines. The liner equations were determined by fitting the experimental date, respectively. Compared to other parameters, heat treatment had more influence on the tensile strength and the tensile plasticity was more sensitive to the forging temperature.

  15. Thermal Phenomena in the Friction Process of the TG15 - Hard Anodic Coating Couple

    Directory of Open Access Journals (Sweden)

    Służałek G.

    2016-09-01

    Full Text Available The paper presents a one-dimensional model of heat conduction in a couple consisting of a cylinder made of a sliding plastic material, TG15, and a cuboid made of alloy AW 6061 coated with a hard anodic coating, where the couple is heated with the heat generated during friction. TG15 is a composite material based on polytetrafluoroethylene (PTFE with a 15% graphite filler, used for piston rings in oil-free air-compressors. Measurement of temperature in the friction zone is extremely important for the understanding and analysis of the phenomena occurring therein. It is practically impossible to introduce a temperature sensor in such a place. Therefore, the interaction taking place in such a couple was modelled using numerical methods. In order to simplify and accelerate the calculations, a one-dimensional model and constant thermophysical parameters of the materials participating in friction were adopted. To solve the proposed model, the finite difference method was used (FDM. The resultant system of equations was solved by means of an explicit scheme.

  16. Primary motor cortex alterations in Alzheimer disease: A study in the 3xTg-AD model.

    Science.gov (United States)

    Orta-Salazar, E; Feria-Velasco, A I; Díaz-Cintra, S

    2017-04-19

    In humans and animal models, Alzheimer disease (AD) is characterised by accumulation of amyloid-β peptide (Aβ) and hyperphosphorylated tau protein, neuronal degeneration, and astrocytic gliosis, especially in vulnerable brain regions (hippocampus and cortex). These alterations are associated with cognitive impairment (loss of memory) and non-cognitive impairment (motor impairment). The purpose of this study was to identify cell changes (neurons and glial cells) and aggregation of Aβ and hyperphosphorylated tau protein in the primary motor cortex (M1) in 3xTg-AD mouse models at an intermediate stage of AD. We used female 3xTg-AD mice aged 11 months and compared them to non-transgenic mice of the same age. In both groups, we assessed motor performance (open field test) and neuronal damage in M1 using specific markers: BAM10 (extracellular Aβ aggregates), tau 499 (hyperphosphorylated tau protein), GFAP (astrocytes), and Klüver-Barrera staining (neurons). Female 3xTg-AD mice in intermediate stages of the disease displayed motor and cellular alterations associated with Aβ and hyperphosphorylated tau protein deposition in M1. Patients with AD display signs and symptoms of functional impairment from early stages. According to our results, M1 cell damage in intermediate-stage AD affects motor function, which is linked to progression of the disease. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. The utility of peripheral thyrotropin receptor mRNA in the management of differentiated thyroid cancer.

    Science.gov (United States)

    Aliyev, Altay; Soundararajan, Saranya; Bucak, Emre; Gupta, Manjula; Hatipoglu, Betul; Nasr, Christian; Siperstein, Allan; Berber, Eren

    2015-10-01

    Our aim was to analyze the utility of peripheral thyrotropin receptor (TSHR) messenger RNA (mRNA) in predicting and detecting the recurrence of differentiated thyroid cancer. Peripheral blood TSHR-mRNA was obtained in 103 patients before and after total thyroidectomy. An analysis was performed to correlate peripheral blood TSHR-mRNA concentration with oncologic outcomes. Tumor types were papillary (n = 92), follicular (n = 9) and Hürthle cell (n = 2) cancer. Preoperative TSHR-mRNA was ≥1.02 ng/μg in 85% (88/103). On follow-up (median 48 months), 10 patients (10 %) developed recurrence. Recurrence rate in patients with a preoperative TSHR-mRNA ≥ 1.02 ng/μg was 11% versus 0% in those with a lesser concentration. TSHR-mRNA correctly diagnosed 7 (70%) of 10 recurrences. Of 19 patients with positive thyroglobulin (Tg) antibodies, TSHR-mRNA confirmed disease-free status in 12 (63%) and recurrence in 1 (5%). For Tg, TSHR-mRNA and whole-body radioactive iodine scan, sensitivity was 70%, 70%, and 75%; specificity 94%, 76%, 97%; PPV 54%, 24%, and 67%; and NPV 97%, 96%, and 98%, respectively, in detecting recurrent disease. This study shows that patients with preoperative TSHR-mRNA ≥1.02 ng/μg may be at a greater risk for recurrence compared with those with a lesser concentration. In the presence of Tg antibodies, TSHR-mRNA accurately predicted disease status in 68% of patients. Its overall performance in detecting recurrence was similar to Tg and whole-body radioactive iodine scan, albeit with lower specificity and PPV. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. The triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio as a predictor of insulin resistance but not of β cell function in a Chinese population with different glucose tolerance status.

    Science.gov (United States)

    Zhou, Meicen; Zhu, Lixin; Cui, Xiangli; Feng, Linbo; Zhao, Xuefeng; He, Shuli; Ping, Fan; Li, Wei; Li, Yuxiu

    2016-06-07

    Triglyceride/high-density lipoprotein-cholesterol (TG/HDL-C) ratio was a surrogate marker of IR; however, the relationship of TG/HDL-C with IR might vary by ethnicity. This study aims to investigate whether lipid ratios-TG/HDL-C, cholesterol/high-density lipoprotein-cholesterol (TC/HDL-C) ratio, low-density lipoprotein-cholesterol/high-density lipoprotein-cholesterol (LDL-C/HDL-C)) could be potential clinical markers of insulin resistance (IR) and β cell function and further to explore the optimal cut-offs in a Chinese population with different levels of glucose tolerance. Four hundred seventy-nine subjects without a history of diabetes underwent a 75 g 2 h Oral Glucose Tolerance Test (OGTT). New-onset diabetes (n = 101), pre-diabetes (n = 186), and normal glucose tolerance (n = 192) were screened. IR was defined by HOMA-IR > 2.69. Based on indices (HOMA-β, early-phase disposition index [DI30], (ΔIns30/ΔGlu30)/HOMA-IR and total-phase index [DI120]) that indicated different phases of insulin secretion, the subjects were divided into two groups, and the lower group was defined as having inadequate β cell compensation. Logistic regression models and accurate estimates of the areas under receiver operating characteristic curves (AUROC) were obtained. In all of the subjects, TG/HDL, TC/HDL-C, LDL-C/HDL-C, and TG were significantly associated with IR. The AUROCs of TG/HDL-C and TG were 0.71 (95 % CI: 0.66-0.75) and 0.71 (95 % CI: 0.65-0.75), respectively. The optimal cut-offs of TG/HDL-C and TG for IR diagnosis were 1.11 and 1.33 mmol/L, respectively. The AUROCs of TC/HDL-C and LDL-C/HDL-C were 0.66 and 0.65, respectively, but they were not acceptable for IR diagnosis. TG/HDL-C,LDL-C/HDL-C and TG were significantly associated with HOMA-β, but AUROCs were less than 0.50; therefore, the lipid ratios could not be predictors of basal β cell dysfunction. None of the lipid ratios was associated with early-phase insulin secretion. Only TG/HDL-C and

  19. Keratinocyte proliferation, differentiation, and apoptosis-Differential mechanisms of regulation by curcumin, EGCG and apigenin

    International Nuclear Information System (INIS)

    Balasubramanian, Sivaprakasam; Eckert, Richard L.

    2007-01-01

    We have proposed that it is important to examine the impact of chemopreventive agents on the function of normal human epidermal keratinocytes since these cells comprise the barrier that protects the body from a range of environmental insults. In this context, it is widely appreciated that cancer may be retarded by consumption or topical application of naturally occurring food-derived chemopreventive agents. Our studies show that (-)-epigallocatechin-3-gallate (EGCG), a green tea-derived polyphenol, acts to enhance the differentiation of normal human keratinocytes as evidenced by its ability to increase involucrin (hINV), transglutaminase type 1 (TG1) and caspase-14 gene expression. EGCG also stimulates keratinocyte morphological differentiation. These actions of EGCG are mediated via activation of a nPKC, Ras, MEKK1, MEK3, p38δ-ERK1/2 signaling cascade which leads to increased activator protein 1 (AP1) and CAATT enhancer binding protein (C/EBP) transcription factor expression, increased binding of these factors to DNA, and increased gene transcription. In contrast, apigenin, a dietary flavonoid derived from plants and vegetables, and curcumin, an agent derived from turmeric, inhibit differentiation by suppressing MAPK signal transduction and reducing API transcription factor level. Curcumin also acts to enhance apoptosis, although EGCG and apigenin do not stimulate apoptosis. In addition, all of these agents inhibit keratinocyte proliferation. These findings indicate that each of these diet-derived chemopreventive agents has a profound impact on normal human keratinocyte function and that they operate via distinct and sometimes opposing mechanisms. However, all are expected to act as chemopreventive agents

  20. The high-production volume fungicide pyraclostrobin induces triglyceride accumulation associated with mitochondrial dysfunction, and promotes adipocyte differentiation independent of PPARγ activation, in 3T3-L1 cells.

    Science.gov (United States)

    Luz, Anthony L; Kassotis, Christopher D; Stapleton, Heather M; Meyer, Joel N

    2018-01-15

    Pyraclostrobin is one of the most heavily used fungicides, and has been detected on a variety of produce, suggesting human exposure occurs regularly. Recently, pyraclostrobin exposure has been linked to a variety of toxic effects, including neurodegeneration and triglyceride (TG) accumulation. As pyraclostrobin inhibits electron transport chain complex III, and as mitochondrial dysfunction is associated with metabolic syndrome (cardiovascular disease, type II diabetes, obesity), we designed experiments to test the hypothesis that mitochondrial dysfunction underlies its adipogenic activity. 3T3-L1 cells were differentiated according to standard protocols in the presence of pyraclostrobin, resulting in TG accumulation. However, TG accumulation occurred without activation of the peroxisome proliferator activated nuclear receptor gamma (PPARγ), the canonical pathway mediating adipogenesis. Furthermore, cells failed to express many markers of adipogenesis (PPARγ, lpl, CEBPα), while co-exposure to pyraclostrobin and two different PPARγ antagonists (GW9662, T0070907) failed to mitigate TG accumulation, suggesting TG accumulation occurred through a PPARγ-independent mechanism. Instead, pyraclostrobin reduced steady-state ATP, mitochondrial membrane potential, basal mitochondrial respiration, ATP-linked respiration, and spare respiratory capacity, demonstrating mitochondrial dysfunction, while reduced expression of genes involved in glucose transport (Glut-4), glycolysis (Pkm, Pfkl, Pfkm), fatty acid oxidation (Cpt-1b), and lipogenesis (Fasn, Acacα, Acacβ) further suggested a disruption of metabolism. Finally, inhibition of cAMP responsive element binding protein (CREB), a PPARγ coactivator, partially mitigated pyraclostrobin-induced TG accumulation, suggesting TG accumulation is occurring through a CREB-driven mechanism. In contrast, rosiglitazone, a known PPARγ agonist, induced TG accumulation in a PPARγ-dependent manner and enhanced mitochondrial function

  1. Mobility of coated and uncoated TiO2 nanomaterials in soil columns--Applicability of the tests methods of OECD TG 312 and 106 for nanomaterials.

    Science.gov (United States)

    Nickel, Carmen; Gabsch, Stephan; Hellack, Bryan; Nogowski, Andre; Babick, Frank; Stintz, Michael; Kuhlbusch, Thomas A J

    2015-07-01

    Nanomaterials are commonly used in everyday life products and during their life cycle they can be released into the environment. Soils and sediments are estimated as significant sinks for those nanomaterials. To investigate and assess the behaviour of nanomaterials in soils and sediments standardized test methods are needed. In this study the applicability of two existing international standardized test guidelines for the testing of nanomaterials, OECD TG 106 "Adsorption/Desorption using a Bath Equilibrium Method" and the OECD TG 312 "Leaching in Soil Columns", were investigated. For the study one coated and two uncoated TiO2 nanomaterials were used, respectively. The results indicate that the OECD TG 106 is not applicable for nanomaterials. However, the test method according to OECD TG 312 was found to be applicable if nano-specific adaptations are applied. The mobility investigations of the OECD TG 312 indicated a material-dependent mobility of the nanomaterials, which in some cases may lead to an accumulation in the upper soil layers. Whereas no significant transport was observed for the uncoated materials for the double-coated material (coating with dimethicone and aluminiumoxide) a significant transport was detected and attributed to the coating. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Trend analysis of body weight parameters, mortality, and incidence of spontaneous tumors in Tg.rasH2 mice.

    Science.gov (United States)

    Paranjpe, Madhav G; Denton, Melissa D; Vidmar, Tom; Elbekai, Reem H

    2014-01-01

    Carcinogenicity studies have been performed in conventional 2-year rodent studies for at least 3 decades, whereas the short-term carcinogenicity studies in transgenic mice, such as Tg.rasH2, have only been performed over the last decade. In the 2-year conventional rodent studies, interlinked problems, such as increasing trends in the initial body weights, increased body weight gains, high incidence of spontaneous tumors, and low survival, that complicate the interpretation of findings have been well established. However, these end points have not been evaluated in the short-term carcinogenicity studies involving the Tg.rasH2 mice. In this article, we present retrospective analysis of data obtained from control groups in 26-week carcinogenicity studies conducted in Tg.rasH2 mice since 2004. Our analysis showed statistically significant decreasing trends in initial body weights of both sexes. Although the terminal body weights did not show any significant trends, there was a statistically significant increasing trend toward body weight gains, more so in males than in females, which correlated with increasing trends in the food consumption. There were no statistically significant alterations in mortality trends. In addition, the incidence of all common spontaneous tumors remained fairly constant with no statistically significant differences in trends. © The Author(s) 2014.

  3. Characterization of powdered fish heads for bone graft biomaterial applications.

    Science.gov (United States)

    Oteyaka, Mustafa Ozgür; Unal, Hasan Hüseyin; Bilici, Namık; Taşçı, Eda

    2013-01-01

    The aim of this study was to define the chemical composition, morphology and crystallography of powdered fish heads of the species Argyrosomus regius for bone graft biomaterial applications. Two sizes of powder were prepared by different grinding methods; Powder A (coarse, d50=68.5 µm) and Powder B (fine, d50=19.1 µm). Samples were analyzed using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), thermogravimetry (TG), and energy dispersive X-ray spectroscopy (EDS). The powder was mainly composed of aragonite (CaCO3) and calcite (CaCO3). The XRD pattern of Powder A and B matched standard aragonite and calcite patterns. In addition, the calcium oxide (CaO) phase was found after the calcination of Powder A. Thermogravimetry analysis confirmed total mass losses of 43.6% and 47.3% in Powders A and B, respectively. The microstructure of Powder A was mainly composed of different sizes and tubular shape, whereas Powder B showed agglomerated particles. The high quantity of CaO and other oxides resemble the chemical composition of bone. In general, the powder can be considered as bone graft after transformation to hydroxyapatite phase.

  4. Adsorption behaviors of thiophene, benzene, and cyclohexene on FAU zeolites: Comparison of CeY obtained by liquid-, and solid-state ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Yucai [College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266555, Shandong (China); Key Laboratory of Petrochemical Catalytic Science and Technology, Liaoning Province, Liaoning Shihua University, Fushun 113001, Liaoning (China); Mo, Zhousheng; Yu, Wenguang; Dong, Shiwei; Duan, Linhai [College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266555, Shandong (China); Gao, Xionghou, E-mail: gaoxionghou@petrochina.com.cn [Petrochemical Research Institute, PetroChina Company Limited, 9 Dongzhimen North Street, Dongcheng District, Beijing 100007 (China); Song, Lijuan, E-mail: lsong56@263.net [College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266555, Shandong (China); Key Laboratory of Petrochemical Catalytic Science and Technology, Liaoning Province, Liaoning Shihua University, Fushun 113001, Liaoning (China)

    2014-02-15

    Cerium containing Y zeolites were prepared by liquid- (L-CeY) and solid- (S-CeY) state ion exchange from NaY and HY, respectively. The structural and textural properties were characterized by XRD and N{sub 2} adsorption, and acidity properties were characterized by NH{sub 3} temperature-programmed desorption (NH{sub 3}-TPD) and in situ FTIR spectrum of chemisorbed pyridine (in situ Py-FTIR). Furthermore, the single component adsorption and multi-component competitive adsorption behavior of thiophene, benzene and cyclohexene on those zeolites have also been studied by using vapor adsorption isotherms, solution adsorption breakthrough curves, thermogravimetry and derivative thermogravimetry (TG/DTG), frequency response (FR) and in situ FTIR techniques. The results indicate that the primary adsorption mode of benzene is simply micropore filling process, but the nature of effect of aromatics on selective adsorption of thiophene is competitive adsorption. The strong chemical adsorptions and protonization reactions of thiophene and cyclohexene occur upon the Brönsted acid sites of the HY and L-CeY zeolites, and the preferable acid catalytic protonization reactions of olefins hinder the further adsorption of sulfur compounds.

  5. Thermal analysis on parchments I: DSC and TGA combined approach for heat damage assessment

    DEFF Research Database (Denmark)

    Fessas, D.; Signorelli, M.; Schiraldi, A.

    2006-01-01

    Ancient, new and artificially aged parchments were investigated with both differential scanning calorimetry (DSC) and thermogravimetry (TGA). Criteria to define a quantitative ranking of the damage experienced by the bulk collagen of historical parchments were assessed. A damage-related correlation...

  6. A Fundamental Metric for Metal Recycling Applied to Coated Magnesium

    NARCIS (Netherlands)

    Meskers, C.E.M.; Reuter, M.A.; Boin, U.; Kvithyld, A.

    2008-01-01

    A fundamental metric for the assessment of the recyclability and, hence, the sustainability of coated magnesium scrap is presented; this metric combines kinetics and thermodynamics. The recycling process, consisting of thermal decoating and remelting, was studied by thermogravimetry and differential

  7. Synthesis and thermal decomposition study of dysprosium trifluoroacetate

    DEFF Research Database (Denmark)

    Opata, Y. A.; Grivel, J.-C.

    2018-01-01

    A study of the thermal decomposition process of dysprosium trifluoroacetate hydrate under flowing argon is presented. Thermogravimetry, differential thermal analysis, evolved gas analysis and ex-situ x-ray diffraction techniques have been employed in the investigation. Three main stages were...

  8. SU-E-I-20: Comprehensive Quality Assurance Test of Second Generation Toshiba Aquilion Large Bore CT Simulator Based On AAPM TG-66 Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D [Toshiba America Medical Systems, Tustin, CA (United States)

    2015-06-15

    Purpose: AAPM radiation therapy committee task group No. 66 (TG-66) published a report which described a general approach to CT simulator QA. The report outlines the testing procedures and specifications for the evaluation of patient dose, radiation safety, electromechanical components, and image quality for a CT simulator. The purpose of this study is to thoroughly evaluate the performance of a second generation Toshiba Aquilion Large Bore CT simulator with 90 cm bore size (Toshiba, Nasu, JP) based on the TG-66 criteria. The testing procedures and results from this study provide baselines for a routine QA program. Methods: Different measurements and analysis were performed including CTDIvol measurements, alignment and orientation of gantry lasers, orientation of the tabletop with respect to the imaging plane, table movement and indexing accuracy, Scanogram location accuracy, high contrast spatial resolution, low contrast resolution, field uniformity, CT number accuracy, mA linearity and mA reproducibility using a number of different phantoms and measuring devices, such as CTDI phantom, ACR image quality phantom, TG-66 laser QA phantom, pencil ion chamber (Fluke Victoreen) and electrometer (RTI Solidose 400). Results: The CTDI measurements were within 20% of the console displayed values. The alignment and orientation for both gantry laser and tabletop, as well as the table movement and indexing and scanogram location accuracy were within 2mm as specified in TG66. The spatial resolution, low contrast resolution, field uniformity and CT number accuracy were all within ACR’s recommended limits. The mA linearity and reproducibility were both well below the TG66 threshold. Conclusion: The 90 cm bore size second generation Toshiba Aquilion Large Bore CT simulator that comes with 70 cm true FOV can consistently meet various clinical needs. The results demonstrated that this simulator complies with the TG-66 protocol in all aspects including electromechanical component

  9. Radioiodine Thyroid Remnant Ablation after Recombinant Human Thyrotropin or Thyroid Hormone Withdrawal in Patients with High-Risk Differentiated Thyroid Cancer

    Directory of Open Access Journals (Sweden)

    Fabián Pitoia

    2012-01-01

    Full Text Available To supplement limited relevant literature, we retrospectively compared ablation and disease outcomes in high-risk differentiated thyroid carcinoma (DTC patients undergoing radioiodine thyroid remnant ablation aided by recombinant human thyrotropin (rhTSH versus thyroid hormone withdrawal/withholding (THW. Our cohort was 45 consecutive antithyroglobulin antibody- (TgAb- negative, T3-T4/N0-N1-Nx/M0 adults ablated with high activities at three referral centers. Ablation success comprised negative (<1 μg/L stimulated serum thyroglobulin (Tg and TgAb, with absent or <0.1% scintigraphic thyroid bed uptake. “No evidence of disease” (NED comprised negative unstimulated/stimulated Tg and no suspicious neck ultrasonography or pathological imaging or biopsy. “Persistent disease” was failure to achieve NED, “recurrence,” loss of NED status. rhTSH patients (n=18 were oftener ≥45 years old and higher stage (P=0.01, but otherwise not different than THW patients (n=27 at baseline. rhTSH patients were significantly oftener successfully ablated compared to THW patients (83% versus 67%, P<0.02. After respective 3.3 yr and 4.5 yr mean follow-ups (P=0.02, NED was achieved oftener (72% versus 59% and persistent disease was less frequent in rhTSH patients (22% versus 33% (both comparisons P=0.03. rhTSH stimulation is associated with at least as good outcomes as is THW in ablation of high-risk DTC patients.

  10. Radioiodine thyroid remnant ablation after recombinant human thyrotropin or thyroid hormone withdrawal in patients with high-risk differentiated thyroid cancer.

    Science.gov (United States)

    Pitoia, Fabián; Marlowe, Robert J; Abelleira, Erika; Faure, Eduardo N; Bueno, Fernanda; Schwarzstein, Diego; Lutfi, Rubén Julio; Niepomniszcze, Hugo

    2012-01-01

    To supplement limited relevant literature, we retrospectively compared ablation and disease outcomes in high-risk differentiated thyroid carcinoma (DTC) patients undergoing radioiodine thyroid remnant ablation aided by recombinant human thyrotropin (rhTSH) versus thyroid hormone withdrawal/withholding (THW). Our cohort was 45 consecutive antithyroglobulin antibody- (TgAb-) negative, T3-T4/N0-N1-Nx/M0 adults ablated with high activities at three referral centers. Ablation success comprised negative (<1 μg/L) stimulated serum thyroglobulin (Tg) and TgAb, with absent or <0.1% scintigraphic thyroid bed uptake. "No evidence of disease" (NED) comprised negative unstimulated/stimulated Tg and no suspicious neck ultrasonography or pathological imaging or biopsy. "Persistent disease" was failure to achieve NED, "recurrence," loss of NED status. rhTSH patients (n = 18) were oftener ≥45 years old and higher stage (P = 0.01), but otherwise not different than THW patients (n = 27) at baseline. rhTSH patients were significantly oftener successfully ablated compared to THW patients (83% versus 67%, P < 0.02). After respective 3.3 yr and 4.5 yr mean follow-ups (P = 0.02), NED was achieved oftener (72% versus 59%) and persistent disease was less frequent in rhTSH patients (22% versus 33%) (both comparisons P = 0.03). rhTSH stimulation is associated with at least as good outcomes as is THW in ablation of high-risk DTC patients.

  11. Compatibilidad química del piracetam determinada por calorimetría diferencial de barrido Chemical compatibility of piracetam determined by differential scanning calorimetry

    Directory of Open Access Journals (Sweden)

    Luis Octavio Martínez Álvarez

    2013-03-01

    Full Text Available Introducción: en la primera etapa de preformulación de un medicamento se seleccionan los excipientes y es importante la realización de los estudios de compatibilidad química entre el ingrediente activo farmacéutico (IFA y excipientes. Una de las técnicas más rápidas para realizar dichos estudios es la Calorimetría diferencial de barrido (DSC, y como técnica complementaria la Termogravimetría (TG. Objetivo: empleando DSC y TG, se realiza un estudio de compatibilidad química entre IFA y excipientes preseleccionados, para comprobar la existencia o no de interacción química. Métodos: el equipo empleado fue el TA3000Mettler, aco­plado a la celda DSC20 y al horno TG50. El IFA utilizado fue Piracetam, y los excipientes: Kollidon VA 64, Estearato de magnesio, Celulosa microcristalina, Polietilenglicol 20 000 y Aerosil. Dichos excipientes se caracterizaron por DSC al igual que el IFA, al cual se le detectó la transición física de fusión. Para el estudio de compatibilidad se prepararon mezclas físicas binarias en una relación de concentración 1:1 Resultados: la figura 1 muestra la detección del punto de fusión por DSC del IFA. Se obtuvieron dos transiciones endotérmicas, comprobándose por TG cuál era la de fusión. La figura 2 muestra los termogramas de las mezclas formadas entre IFA y excipientes. Conclusiones: no se detectó aparición de nuevos picos, por lo que se infiere que no hay incompatibilidad química entre las sustancias estudiadas y se recomienda el uso de los excipientes para el desarrollo de la formulación farmacéutica.Introduction: the first phase of the drug preformulation comprises the selection of excipients and the conduction of studies on chemical compatibility between pharmacologically active ingredient and the excipients. One of the quickest techniques is the differential scanning calorimetry and the supplementary technique called thermogravimetic analysis. Objective: to conduct a chemical compatibility

  12. Evaluation of glass transition temperature and dynamic mechanical properties of autopolymerized hard direct denture reline resins.

    Science.gov (United States)

    Takase, Kazuma; Watanabe, Ikuya; Kurogi, Tadafumi; Murata, Hiroshi

    2015-01-01

    This study assessed methods for evaluation of glass transition temperature (Tg) of autopolymerized hard direct denture reline resins using dynamic mechanical analysis and differential scanning calorimetry in addition to the dynamic mechanical properties. The Tg values of 3 different reline resins were determined using a dynamic viscoelastometer and differential scanning calorimeter, and rheological parameters were also determined. Although all materials exhibited higher storage modulus and loss modulus values, and a lower loss tangent at 37˚C with a higher frequency, the frequency dependence was not large. Tg values obtained by dynamic mechanical analysis were higher than those by differential scanning calorimetry and higher frequency led to higher Tg, while more stable Tg values were also obtained by that method. These results suggest that dynamic mechanical analysis is more advantageous for characterization of autopolymerized hard direct denture reline resins than differential scanning calorimetry.

  13. Deficits in synaptic function occur at medial perforant path-dentate granule cell synapses prior to Schaffer collateral-CA1 pyramidal cell synapses in the novel TgF344-Alzheimer's Disease Rat Model.

    Science.gov (United States)

    Smith, Lindsey A; McMahon, Lori L

    2018-02-01

    Alzheimer's disease (AD) pathology begins decades prior to onset of clinical symptoms, and the entorhinal cortex and hippocampus are among the first and most extensively impacted brain regions. The TgF344-AD rat model, which more fully recapitulates human AD pathology in an age-dependent manner, is a next generation preclinical rodent model for understanding pathophysiological processes underlying the earliest stages of AD (Cohen et al., 2013). Whether synaptic alterations occur in hippocampus prior to reported learning and memory deficit is not known. Furthermore, it is not known if specific hippocampal synapses are differentially affected by progressing AD pathology, or if synaptic deficits begin to appear at the same age in males and females in this preclinical model. Here, we investigated the time-course of synaptic changes in basal transmission, paired-pulse ratio, as an indirect measure of presynaptic release probability, long-term potentiation (LTP), and dendritic spine density at two hippocampal synapses in male and ovariectomized female TgF344-AD rats and wildtype littermates, prior to reported behavioral deficits. Decreased basal synaptic transmission begins at medial perforant path-dentate granule cell (MPP-DGC) synapses prior to Schaffer-collateral-CA1 (CA3-CA1) synapses, in the absence of a change in paired-pulse ratio (PPR) or dendritic spine density. N-methyl-d-aspartate receptor (NMDAR)-dependent LTP magnitude is unaffected at CA3-CA1 synapses at 6, 9, and 12months of age, but is significantly increased at MPP-DGC synapses in TgF344-AD rats at 6months only. Sex differences were only observed at CA3-CA1 synapses where the decrease in basal transmission occurs at a younger age in males versus females. These are the first studies to define presymptomatic alterations in hippocampal synaptic transmission in the TgF344-AD rat model. The time course of altered synaptic transmission mimics the spread of pathology through hippocampus in human AD and provides

  14. Polymorphisms in Genes Involved in Fatty Acid β-Oxidation Interact with Dietary Fat Intakes to Modulate the Plasma TG Response to a Fish Oil Supplementation

    Science.gov (United States)

    Bouchard-Mercier, Annie; Rudkowska, Iwona; Lemieux, Simone; Couture, Patrick; Vohl, Marie-Claude

    2014-01-01

    A large inter-individual variability in the plasma triglyceride (TG) response to an omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation has been observed. The objective was to examine gene-diet interaction effects on the plasma TG response after a fish oil supplementation, between single-nucleotide polymorphisms (SNPs) within genes involved in fatty acid β-oxidation and dietary fat intakes. Two hundred and eight (208) participants were recruited in the greater Quebec City area. The participants completed a six-week fish oil supplementation (5 g fish oil/day: 1.9–2.2 g EPA and 1.1 g DHA). Dietary fat intakes were measured using three-day food records. SNPs within RXRA, CPT1A, ACADVL, ACAA2, ABCD2, ACOX1 and ACAA1 genes were genotyped using TAQMAN methodology. Gene-diet interaction effects on the plasma TG response were observed for SNPs within RXRA (rs11185660, rs10881576 and rs12339187) and ACOX1 (rs17583163) genes. For rs11185660, fold changes in RXRA gene expression levels were different depending on SFA intakes for homozygotes T/T. Gene-diet interaction effects of SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes may be important in understanding the inter-individual variability in plasma TG levels and in the plasma TG response to a fish oil supplementation. PMID:24647074

  15. Polymorphisms in Genes Involved in Fatty Acid β-Oxidation Interact with Dietary Fat Intakes to Modulate the Plasma TG Response to a Fish Oil Supplementation

    Directory of Open Access Journals (Sweden)

    Annie Bouchard-Mercier

    2014-03-01

    Full Text Available A large inter-individual variability in the plasma triglyceride (TG response to an omega-3 polyunsaturated fatty acid (n-3 PUFA supplementation has been observed. The objective was to examine gene-diet interaction effects on the plasma TG response after a fish oil supplementation, between single-nucleotide polymorphisms (SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes. Two hundred and eight (208 participants were recruited in the greater Quebec City area. The participants completed a six-week fish oil supplementation (5 g fish oil/day: 1.9–2.2 g EPA and 1.1 g DHA. Dietary fat intakes were measured using three-day food records. SNPs within RXRA, CPT1A, ACADVL, ACAA2, ABCD2, ACOX1 and ACAA1 genes were genotyped using TAQMAN methodology. Gene-diet interaction effects on the plasma TG response were observed for SNPs within RXRA (rs11185660, rs10881576 and rs12339187 and ACOX1 (rs17583163 genes. For rs11185660, fold changes in RXRA gene expression levels were different depending on SFA intakes for homozygotes T/T. Gene-diet interaction effects of SNPs within genes involved in fatty acid β-oxidation and dietary fat intakes may be important in understanding the inter-individual variability in plasma TG levels and in the plasma TG response to a fish oil supplementation.

  16. [Long term follow up of medical treatment of differentiated thyroid cancer].

    Science.gov (United States)

    Jaffiol, C; Daures, J P; Nsakala, N; Guerenova, J; Baldet, L; Pujol, P; Vannereau, D; Bringer, J

    1995-01-01

    106 patients, 114 W, 27 M, were thyroidectomized for differentiated thyroid cancer (follicular 29.3%-papillary 54.3%) with different stages of gravity (NO: 48.2% - N1: 32.8% - N2: 19%). Neck dissection was used in cases of involved nodes. One or several doses of 131 I were given to 126 subjects, 106 patients were treated with LT4 (mean daily dose: 2.5 micrograms/kg BW). 23 patients presenting intolerance to LT4 with non suppressed TSH for 13 of them were treated by an association of TRIAC + LT4. The follow up included a yearly check up involving clinical examination, plasma Tg and TSH assessment, neck ultrasonography and X-ray of the chest. Therapy was stopped for 4 weeks in cases with Tg above its detectable value and a total body scan performed with Tg and TSH controls. The mean duration of follow up was 94.5 +/- 67.7 months and extended to more than 5 years for 61% of the patients. We observed 22 relapses of the tumor with 4 deaths. Age less then 45 years, appears as the best factor of prognosis. 2 groups of patients were compared to evaluate the incidence of TSH suppression on the relapse free survival (group 1 n = 30 with a TSH 1 mU/l during the follow up). The relapse free survival was shorter in group 2 (p = 0.01). Association of TRIAC with LT4 leads to a reduction of the daily dose of LT4 (m = 25 micrograms/day) with a significant improvement of TSH suppression and clinical tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Large Discrepancy in the Results of Sensitive Measurements of Thyroglobulin Antibodies in the Follow-Up on Thyroid Cancer

    DEFF Research Database (Denmark)

    Nygaard, Birte; Bentzen, Jens; Laurberg, Peter

    2012-01-01

    UNLABELLED: During follow-up on patients treated for differentiated thyroid cancer, thyroglobulin (Tg) antibodies can interfere with the Tg assay, making the use of Tg less reliable as a tumor marker. PURPOSE: To compare Tg and Tg autoantibodies (Tg-Ab) methods used in Denmark, regarding the number...

  18. Bulk synthesis of nanocrystalline urania powders by citrate gel-combustion method

    International Nuclear Information System (INIS)

    Sanjay Kumar, D.; Ananthasivan, K.; Venkata Krishnan, R.; Amirthapandian, S.; Dasgupta, Arup

    2016-01-01

    Bulk quantities (60 g) of nanocrystalline (nc) free flowing urania powders with crystallite size ranging from 38 to 252 nm have been synthesized for the first time by the citrate gel combustion method. A systematic study of the influence of the fuel (citric acid) to oxidant (nitrate) ratio (R) on the characteristics of the urania powders has been carried out for the first time. Mixture with an “R” value of 0.25 exhibited a vigorous auto-ignition reaction. This reaction was investigated with Differential Scanning Calorimetry (DSC) and in-situ thermogravimetry coupled with differential thermal analysis and mass spectrometry (TG-DTA-MS). The bulk density, specific surface area, X-ray crystallite size, residual carbon and size distribution of particles of this powder were unique. Microscopic and microstructural investigation of selected samples revealed the presence of nanocrystals with irregular exfoliated morphology; their Electron Energy Loss Spectra testified the covalency of the U–O bond. - Highlights: • Bulk quantities of nanocrystalline urania were prepared for the first time using citrate gel combustion method. • Volume combustion was observed in mixtures with fuel to nitrate ratio (R) 0.25. • The value of R was found to significantly influence the characteristics of the final product. • Typical exfoliated microstructure and nanopores were observed. • Established correlation between particle size distribution and bulk density, X-ray crystallite size and lattice strain. • Relationship between fuel to nitrate (R) mole ratio and physical characteristics of powders were also established.

  19. Using IR spectroscopy and multivariate curve resolution to elucidate mechanism of heat-induced decomposition of an organic complex

    DEFF Research Database (Denmark)

    Karpushkin, Evgeny; Gvozdik, Nataliya; Kucheryavskiy, Sergey V.

    the opportunity to carry out simultaneous thermogravimetry/differential scanning calorimetry analysis and IR/Raman/mass spectrometry investigation of the evolving gaseous products. However, elucidation of the mechanism of the reactions occurring upon heat- ing is not completely straightforward, due to a number...

  20. Usefulness of recombinant human TSH aided radioiodine doses administered in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Pitoia, Fabian; El Tamer, Elias; Schere, Daniel B.; Passerieu, Mariano; Bruno, Oscar D.; Niepominiszcze, Hugo

    2006-01-01

    The published studies confirming the safety and efficacy of rh TSH for diagnostic purposes have led to an increased interest in its use for preparation for radioiodine (RI) dose administration in patients with recurrent or persistent differentiated thyroid carcinoma (DTC). In order to establish the efficacy of RI therapy after rh TSH, we have reviewed 39 rh TSH-aided radioiodine treatments in a series of 28 DTC patients. Patients were divided into two groups: GI (n=17), with previous thyroid bed uptake and undetectable thyroglobulin (Tg) levels under levothyroxine treatment and GII (n=11), with proven metastatic local or distant disease. Median follow-up after the first rh TSH-aided radioiodine treatment was 32 ± 13 months (range 8 to 54 months). Sixteen patients (94%) in GI were rendered disease free and one patient was shown to have persistent disease. In GII, the post therapy whole body scan showed pathological uptakes in all cases: in four patients in lungs, in four in mediastinum and in three in lateral neck. In two patients with mediastinum uptake, Tg levels were undetectable after rh TSH. In the follow-up, two patients with lateral neck uptake were rendered disease free, four patients died (three due to thyroid cancer) and five out of the remaining patients have persistent disease. In conclusion, rh TSH aided therapy was helpful to eliminate normal thyroid bed remnants in 16/17 (94%) patients (GI). rh TSH stimulated Tg was undetectable in two patients with mediastinal metastasis. We believe that rh TSH is a good alternative to levothyroxine withdrawal for the treatment of DTC with radioactive iodine, increasing the quality of life in these patients. Caution should be recommended in the follow-up of unselected DTC patients only with stimulated Tg levels. (author) [es

  1. Thermal behavior and pyrolytic degradation kinetics of polymeric mixtures from waste packaging plastics

    Directory of Open Access Journals (Sweden)

    R. Tuffi

    2018-01-01

    Full Text Available The thermal behavior and pyrolytic kinetic analysis of main waste polymers (polypropylene (PP, polyethylene film (PE, poly(ethylene terephthalate (PET, polystyrene (PS and three synthetic mixtures representing commingled postconsumer plastics wastes (CPCPWs output from material recovery facilities were studied. Thermogravimetry (TG pyrolysis experiments revealed that the thermal degradation of single polymers and the synthetic mixture enriched in PP occurred in one single step. The other two mixtures underwent a two-consecutive, partially overlapping degradation steps, whose peaks related to the first-order derivative of TG were deconvoluted into two distinct processes. Further TG experiments carried out on binary mixtures (PS/PP, PET/PP, PET/PEfilm and PP/PEfilm showed a thermal degradation reliance on composition, structure and temperatures of single polymer components. A kinetic analysis was made for each step using the Kissinger-Akahira-Sunose (KAS method, thus determining almost constant activation energy (Ea for pyrolysis of PS, PET, PP and PE film in the range 0.25<α<0.85, unlike for pyrolysis of CPCPWs, with particular reference to CPCPW1 and the second step of CPCPW2 and CPCPW3, both ascribable to degradation of PP and PE film. To account for the reliability of these values the integral isoconversional modified method developed by Vyazovkin was also applied.

  2. XRD and DSC study of the formation and the melting of a new zeolite like borosilicate CsBSi5O12 and (Cs,Rb)BSi5O12 solid solutions

    International Nuclear Information System (INIS)

    Bubnova, R.S.; Ugolkov, V.L.; Krzhizhanovskaya, M.G.; Filatov, S.K.; Paufler, P.

    2007-01-01

    Polycrystalline CsBSi 5 O 12 was prepared from a stoichiometric mixture by solid-state reaction above 1000 C. The solid solutions Cs 1-x Rb x BSi 5 O 12 were obtained at 1000 C during a long heat treatment of polycrystalline Cs 1-x Rb x BSi 2 O 6 boropollucites (x Rb = 0, 0.05, 0.2, 0.4). A new borosilicate compound and its solid solutions were studied using X-ray powder diffraction (XRD), annealing, differential scanning calorimetry (DSC), and thermogravimetry (TG). For Cs,Rb-boropollucites the new phase formation is accompanied by significant mass losses detected by DSC and TG. The following mechanism of phase transformations is assumed: (Cs,Rb)BSi 2 O 6 → (Cs,Rb)BSi 5 O 12 + (Cs,Rb)BO 2 ↑. The zeolite phase forms as a result of the boropollucite decomposition over 1000 C. Zeolite decomposes also on further heating and the SiO 2 reflections are observed in the XRD pattern only. Thus above 1000 C both boropollucite and zeolite phases are unstable presumably due to the ability of the alkali cations to leave the structure. Using XRD the unit cell parameters of CsBSi 5 O 12 have been determined in the orthorhombic crystal system: a = 16.242(4) A, b = 13.360(4) A, c = 4.874(1) A. The compound is isostructural with the zeolite compound CsAlSi 5 O 12 . In the crystal structure of Cs 1-x Rb x BSi 5 O 12 solid solutions the changes of cell parameters are insignificant under the substitution of Cs by Rb atoms that indicates a very limited substitution range. (orig.)

  3. A new cocrystal of Gliclazide with Tromethamine: Preparation and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Marcus Lima; Silva, Francisca Celia da; Silva Filho, Silverio Ferreira da; Pereira, Andreia Cardoso; Santos, Adenilson Oliveira dos; Ribeiro, Paulo Roberto da Silva, E-mail: mrcs49@hotmail.com [Universidade Federal do Maranhao (UFMA), Sao Luis (Brazil)

    2016-07-01

    Full text: Gliclazide (GLZ) is an antidiabetic widely used for patients with Diabetes Mellitus Type II. This compound has low aqueous solubility (55 mg l{sup -1}) and low dissolution rate. Such characteristics are limiting factors that contribute to reducing its bioavailability. Studies show the cocrystals are a promising strategy to improve the physicochemical properties of drugs, such as dissolution rate and bioavailability[1]. The objective of present investigation was the preparation (by assisted liquid grinding) and characterization of a new cocrystal of GLZ with the coformer tromethamine (TRIS). The sample was synthesized in molar ratio 1:1 and characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Thermogravimetry and Differential Thermal Analysis (TG/DTA). The DSC showed melting point different from the pure compounds, two endothermic events occurring: the first peak at 133.77 °C and the second peak at 146.97 °C, which may indicate the formation of the cocrystal. The thermal stability profile revealed three mass loss events for the TG. The first event indicated a peak weight loss at 161.8 °C, to 14.06% of the original mass. The second event showed peak temperature of 222.80 °C corresponding to 55.80% of mass. The third occurred at 305.0 °C with loss of 27.3% by mass. In the analysis DTA was observed an endothermic event with peak at 129.37 °C which may be due to phase transition characteristic of the coformador; another endothermic peak emerged at a temperature of 141.0 °C, which may be related to melting of the test compound. The results PXRD revealed changes in diffractograms of sample, showing crystallographic new peaks which did not occur in the spectra of pure compounds (GLZ and TRIS), indicating novel crystalline structure, and thus confirm the formation of the cocrystal. References: [1] Nanjwade, V. et al. J. Applied Pharmaceutical Sciences, v.1, n.1, p.1-5 (2011). (author)

  4. A new cocrystal of Gliclazide with Tromethamine: Preparation and characterization

    International Nuclear Information System (INIS)

    Sousa, Marcus Lima; Silva, Francisca Celia da; Silva Filho, Silverio Ferreira da; Pereira, Andreia Cardoso; Santos, Adenilson Oliveira dos; Ribeiro, Paulo Roberto da Silva

    2016-01-01

    Full text: Gliclazide (GLZ) is an antidiabetic widely used for patients with Diabetes Mellitus Type II. This compound has low aqueous solubility (55 mg l -1 ) and low dissolution rate. Such characteristics are limiting factors that contribute to reducing its bioavailability. Studies show the cocrystals are a promising strategy to improve the physicochemical properties of drugs, such as dissolution rate and bioavailability[1]. The objective of present investigation was the preparation (by assisted liquid grinding) and characterization of a new cocrystal of GLZ with the coformer tromethamine (TRIS). The sample was synthesized in molar ratio 1:1 and characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Thermogravimetry and Differential Thermal Analysis (TG/DTA). The DSC showed melting point different from the pure compounds, two endothermic events occurring: the first peak at 133.77 °C and the second peak at 146.97 °C, which may indicate the formation of the cocrystal. The thermal stability profile revealed three mass loss events for the TG. The first event indicated a peak weight loss at 161.8 °C, to 14.06% of the original mass. The second event showed peak temperature of 222.80 °C corresponding to 55.80% of mass. The third occurred at 305.0 °C with loss of 27.3% by mass. In the analysis DTA was observed an endothermic event with peak at 129.37 °C which may be due to phase transition characteristic of the coformador; another endothermic peak emerged at a temperature of 141.0 °C, which may be related to melting of the test compound. The results PXRD revealed changes in diffractograms of sample, showing crystallographic new peaks which did not occur in the spectra of pure compounds (GLZ and TRIS), indicating novel crystalline structure, and thus confirm the formation of the cocrystal. References: [1] Nanjwade, V. et al. J. Applied Pharmaceutical Sciences, v.1, n.1, p.1-5 (2011). (author)

  5. Interactions of coal gangue and pine sawdust during combustion of their blends studied using differential thermogravimetric analysis.

    Science.gov (United States)

    Zhang, Yuanyuan; Zhang, Zhezi; Zhu, Mingming; Cheng, Fangqin; Zhang, Dongke

    2016-08-01

    The interactions between coal gangue and pine sawdust during the combustion process were studied using thermogravimetric analysis. The effect of the blending ratio, oxygen concentration and heating rate on the weight loss (TG) and differential thermogravimetric (TGA) profiles was examined. The TG and DTG curves of the blends were not additives of those of the individual materials, suggesting that interactions between coal gangue and pine sawdust had occurred during the combustion, especially in the temperature range of 400-600°C. Kinetic analysis confirmed that the combustion of coal gangue, pine sawdust and their blends was chemical reaction controlled. Further analysis revealed that the interactions between coal gangue and pine sawdust were primarily due to thermal effects rather than structural changes, with the thermal inertia of coal gangue dominating over the behaviour of the blends. The interactions decreased with decreasing the coal gangue ratio in the blend, oxygen concentration and heating rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Characterization of the molecular distribution of drugs in glassy solid dispersions at the nano-meter scale, using differential scanning calorimetry and gravimetric water vapour sorption techniques.

    Science.gov (United States)

    van Drooge, D J; Hinrichs, W L J; Visser, M R; Frijlink, H W

    2006-03-09

    The molecular distribution in fully amorphous solid dispersions consisting of poly(vinylpyrrolidone) (PVP)-diazepam and inulin-diazepam was studied. One glass transition temperature (T(g)), as determined by temperature modulated differential scanning calorimetry (TMDSC), was observed in PVP-diazepam solid dispersions prepared by fusion for all drug loads tested (10-80 wt.%). The T(g) of these solid dispersions gradually changed with composition and decreased from 177 degrees C for pure PVP to 46 degrees C for diazepam. These observations indicate that diazepam was dispersed in PVP on a molecular level. However, in PVP-diazepam solid dispersions prepared by freeze drying, two T(g)'s were observed for drug loads above 35 wt.% indicating phase separation. One T(g) indicated the presence of amorphous diazepam clusters, the other T(g) was attributed to a PVP-rich phase in which diazepam was dispersed on a molecular level. With both the value of the latter T(g) and the DeltaC(p) of the diazepam glass transition the concentrations of molecular dispersed diazepam could be calculated (27-35 wt.%). Both methods gave similar results. Water vapour sorption (DVS) experiments revealed that the PVP-matrix was hydrophobised by the incorporated diazepam. TMDSC and DVS results were used to estimate the size of diazepam clusters in freeze dried PVP-diazepam solid dispersions, which appeared to be in the nano-meter range. The inulin-diazepam solid dispersions prepared by spray freeze drying showed one T(g) for drug loads up to 35 wt.% indicating homogeneous distribution on a molecular level. However, this T(g) was independent of the drug load, which is unexpected because diazepam has a lower T(g) than inulin (46 and 155 degrees C, respectively). For higher drug loads, a T(g) of diazepam as well as a T(g) of the inulin-rich phase was observed, indicating the formation of amorphous diazepam clusters. From the DeltaC(p) of the diazepam glass transition the amount of molecularly dispersed

  7. Thyroid scintigraphy and perchlorate test after recombinant human TSH: a new tool for the differential diagnosis of congenital hypothyroidism during infancy

    International Nuclear Information System (INIS)

    Fugazzola, Laura; Vannucchi, Guia; Mannavola, Deborah; Beck-Peccoz, Paolo; Persani, Luca; Carletto, Marco; Longari, Virgilio; Vigone, Maria C.; Cortinovis, Francesca; Weber, Giovanna; Beccaria, Luciano

    2007-01-01

    Prompt initiation of l-thyroxine therapy in neonates with congenital hypothyroidism (CH) often prevents the performance of functional studies. Aetiological diagnosis is thus postponed until after infancy, when the required investigations are performed after l-thyroxine withdrawal. The aim of this study was to verify the efficacy and safety of new protocols for rhTSH (Thyrogen) testing during l-thyroxine replacement in the differential diagnosis of CH. Ten CH patients (15-144 months old) were studied. Seven had neonatal evidence of gland in situ at the ultrasound examination performed at enrolment and received two rhTSH injections (4 μg/kg daily, i.m.) with 123 I scintigraphy and perchlorate test on day 3. Three patients with an ultrasound diagnosis of thyroid dysgenesis received three rhTSH injections with 123 I scintigraphy on days 3 and 4. TSH and thyroglobulin (Tg) determinations were performed on days 1, 3 and 4, and neck ultrasound on day 1. rhTSH stimulation caused Tg levels to increase in eight cases. Blunted Tg responses were seen in two patients with ectopia and hypoplasia. Interestingly, in two cases the association of different developmental defects was demonstrated. Perchlorate test revealed a total iodide organification defect in two patients, including one with a neonatal diagnosis of Pendred's syndrome, who were subsequently found to harbour TPO mutations. rhTSH did not cause notable side-effects. These new rhTSH protocols always resulted in accurate disease characterisation, allowing specific management and targeted genetic analyses. Thus, rhTSH represents a valid and safe alternative to l-thyroxine withdrawal in the differential diagnosis of CH in paediatric patients. (orig.)

  8. Thyroid scintigraphy and perchlorate test after recombinant human TSH: a new tool for the differential diagnosis of congenital hypothyroidism during infancy

    Energy Technology Data Exchange (ETDEWEB)

    Fugazzola, Laura; Vannucchi, Guia; Mannavola, Deborah; Beck-Peccoz, Paolo [University of Milan and Fondazione Policlinico IRCCS, Department of Medical Sciences, Milan (Italy); Persani, Luca [University of Milan and Istituto Auxologico Italiano, Department of Medical Sciences, Via Zucchi, Cusano, Milan (Italy); Carletto, Marco; Longari, Virgilio [Fondazione Policlinico IRCCS, Department of Nuclear Medicine, Milan (Italy); Vigone, Maria C.; Cortinovis, Francesca; Weber, Giovanna [Universita Vita-Salute S. Raffaele, Centro di Endocrinologia dell' Infanzia e dell' Adolescenza, Milan (Italy); Beccaria, Luciano [A. Manzoni Hospital, Paediatric Unit, Lecco (Italy)

    2007-09-15

    Prompt initiation of l-thyroxine therapy in neonates with congenital hypothyroidism (CH) often prevents the performance of functional studies. Aetiological diagnosis is thus postponed until after infancy, when the required investigations are performed after l-thyroxine withdrawal. The aim of this study was to verify the efficacy and safety of new protocols for rhTSH (Thyrogen) testing during l-thyroxine replacement in the differential diagnosis of CH. Ten CH patients (15-144 months old) were studied. Seven had neonatal evidence of gland in situ at the ultrasound examination performed at enrolment and received two rhTSH injections (4 {mu}g/kg daily, i.m.) with {sup 123}I scintigraphy and perchlorate test on day 3. Three patients with an ultrasound diagnosis of thyroid dysgenesis received three rhTSH injections with {sup 123}I scintigraphy on days 3 and 4. TSH and thyroglobulin (Tg) determinations were performed on days 1, 3 and 4, and neck ultrasound on day 1. rhTSH stimulation caused Tg levels to increase in eight cases. Blunted Tg responses were seen in two patients with ectopia and hypoplasia. Interestingly, in two cases the association of different developmental defects was demonstrated. Perchlorate test revealed a total iodide organification defect in two patients, including one with a neonatal diagnosis of Pendred's syndrome, who were subsequently found to harbour TPO mutations. rhTSH did not cause notable side-effects. These new rhTSH protocols always resulted in accurate disease characterisation, allowing specific management and targeted genetic analyses. Thus, rhTSH represents a valid and safe alternative to l-thyroxine withdrawal in the differential diagnosis of CH in paediatric patients. (orig.)

  9. Autoimmunity in differentiated thyroid cancer: significance and related clinical problems

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, Ulla; Rasmussen, Ase Krogh

    2011-01-01

    Coexistence of differentiated thyroid cancer (DTC) and thyroid autoimmune diseases could represent a mere coincidence due to the frequent occurrence of autoimmunity, but there may also be a pathological and causative link between the two conditions. The coincidence of DTC with Hashimoto's disease...... has been variably reported at between 0.5 and 22.5% and of DTC with Graves' disease between 0 and 9.8%. In this review available evidence for thyroid autoimmunity in DTC is summarized and it is concluded that thyroid cancer does coexist with thyroid autoimmunity, implying that patients treated...... TgAb measurements may be used as a surrogate marker for recurrence of thyroid cancer during the long-term monitoring of DTC patients....

  10. Autoimmunity in differentiated thyroid cancer: significance and related clinical problems

    DEFF Research Database (Denmark)

    Feldt-Rasmussen, Ulla; Rasmussen, Ase Krogh

    2010-01-01

    Coexistence of differentiated thyroid cancer (DTC) and thyroid autoimmune diseases could represent a mere coincidence due to the frequent occurrence of autoimmunity, but there may also be a pathological and causative link between the two conditions. The coincidence of DTC with Hashimoto's disease...... has been variably reported at between 0.5 and 22.5% and of DTC with Graves' disease between 0 and 9.8%. In this review available evidence for thyroid autoimmunity in DTC is summarized and it is concluded that thyroid cancer does coexist with thyroid autoimmunity, implying that patients treated...... TgAb measurements may be used as a surrogate marker for recurrence of thyroid cancer during the long-term monitoring of DTC patients....

  11. TG-MS analysis and kinetic study for thermal decomposition of six representative components of municipal solid waste under steam atmosphere.

    Science.gov (United States)

    Zhang, Jinzhi; Chen, Tianju; Wu, Jingli; Wu, Jinhu

    2015-09-01

    Thermal decomposition of six representative components of municipal solid waste (MSW, including lignin, printing paper, cotton, rubber, polyvinyl chloride (PVC) and cabbage) was investigated by thermogravimetric-mass spectroscopy (TG-MS) under steam atmosphere. Compared with TG and derivative thermogravimetric (DTG) curves under N2 atmosphere, thermal decomposition of MSW components under steam atmosphere was divided into pyrolysis and gasification stages. In the pyrolysis stage, the shapes of TG and DTG curves under steam atmosphere were almost the same with those under N2 atmosphere. In the gasification stage, the presence of steam led to a greater mass loss because of the steam partial oxidation of char residue. The evolution profiles of H2, CH4, CO and CO2 were well consistent with DTG curves in terms of appearance of peaks and relevant stages in the whole temperature range, and the steam partial oxidation of char residue promoted the generation of more gas products in high temperature range. The multi-Gaussian distributed activation energy model (DAEM) was proved plausible to describe thermal decomposition behaviours of MSW components under steam atmosphere. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Multi-valued logic circuits using hybrid circuit consisting of three gates single-electron transistors (TG-SETs) and MOSFETs.

    Science.gov (United States)

    Shin, SeungJun; Yu, YunSeop; Choi, JungBum

    2008-10-01

    New multi-valued logic (MVL) families using the hybrid circuits consisting of three gates single-electron transistors (TG-SETs) and a metal-oxide-semiconductor field-effect transistor (MOSFET) are proposed. The use of SETs offers periodic literal characteristics due to Coulomb oscillation of SET, which allows a realization of binary logic (BL) circuits as well as multi-valued logic (MVL) circuits. The basic operations of the proposed MVL families are successfully confirmed through SPICE circuit simulation based on the physical device model of a TG-SET. The proposed MVL circuits are found to be much faster, but much larger power consumption than a previously reported MVL, and they have a trade-off between speed and power consumption. As an example to apply the newly developed MVL families, a half-adder is introduced.

  13. In silico analysis and gene expression of TgNAC01 transcription factor involved in xylogenesis and abiotic stress in Tectona grandis.

    Directory of Open Access Journals (Sweden)

    Vladimir Camel Paucar

    2017-09-01

    Full Text Available Secondary xylem is the most abundant component of plant biomass. Therefore, knowing the genes that regulate its formation would help to design strategies for wood genetic improvement. Thus, the objective of this work was to perform computational analysis of the primary and secondary structure of the TgNAC01 transcription factor (FT of Tectona grandis