Reversal of cisplatin resistance in non-small cell lung cancer stem cells by Taxus chinensis var.

Science.gov (United States)

Jiang, Y Q; Xu, X P; Guo, Q M; Xu, X C; Liu, Q Y; An, S H; Xu, J L; Su, F; Tai, J B

2016-09-02

Drug resistance in cells is a major impedance to successful treatment of lung cancer. Taxus chinensis var. inhibits the growth of tumor cells and promotes the synthesis of interleukins 1 and 2 and tumor necrosis factor, enhancing immune function. In this study, T. chinensis var.-induced cell death was analyzed in lung cancer cells (H460) enriched for stem cell growth in a defined serum-free medium. Taxus-treated stem cells were also analyzed for Rhodamine 123 (Rh-123) expression by flow cytometry, and used as a standard functional indicator of MDR. The molecular basis of T. chinensis var.-mediated drug resistance was established by real-time PCR analysis of ABCC1, ABCB1, and lung resistance-related protein (LRP) mRNA, and western blot analysis of MRP1, MDR1, and LRP. Our results revealed that stem cells treated with higher doses of T. chinensis var. showed significantly lower growth inhibition rates than did H460 cells (P var. and cisplatin was also significantly inhibited (P var. (P var.-treated stem cells showed significant downregulation of the ABCC1, ABCB1, and LRP mRNA and MRP1, MDR1, and LRP (P var.-mediated downregulation of MRP1, MDR1, and LRP might contribute to the reversal of drug resistance in non-small cell lung cancer stem cells.

Deep sequencing reveals transcriptome re-programming of Taxus × media cells to the elicitation with methyl jasmonate.

Science.gov (United States)

Sun, Guiling; Yang, Yanfang; Xie, Fuliang; Wen, Jian-Fan; Wu, Jianqiang; Wilson, Iain W; Tang, Qi; Liu, Hongwei; Qiu, Deyou

2013-01-01

Plant cell culture represents an alternative source for producing high-value secondary metabolites including paclitaxel (Taxol®), which is mainly produced in Taxus and has been widely used in cancer chemotherapy. The phytohormone methyl jasmonate (MeJA) can significantly increase the production of paclitaxel, which is induced in plants as a secondary metabolite possibly in defense against herbivores and pathogens. In cell culture, MeJA also elicits the accumulation of paclitaxel; however, the mechanism is still largely unknown. To obtain insight into the global regulation mechanism of MeJA in the steady state of paclitaxel production (7 days after MeJA addition), especially on paclitaxel biosynthesis, we sequenced the transcriptomes of MeJA-treated and untreated Taxus × media cells and obtained ∼ 32.5 M high quality reads, from which 40,348 unique sequences were obtained by de novo assembly. Expression level analysis indicated that a large number of genes were associated with transcriptional regulation, DNA and histone modification, and MeJA signaling network. All the 29 known genes involved in the biosynthesis of terpenoid backbone and paclitaxel were found with 18 genes showing increased transcript abundance following elicitation of MeJA. The significantly up-regulated changes of 9 genes in paclitaxel biosynthesis were validated by qRT-PCR assays. According to the expression changes and the previously proposed enzyme functions, multiple candidates for the unknown steps in paclitaxel biosynthesis were identified. We also found some genes putatively involved in the transport and degradation of paclitaxel. Potential target prediction of miRNAs indicated that miRNAs may play an important role in the gene expression regulation following the elicitation of MeJA. Our results shed new light on the global regulation mechanism by which MeJA regulates the physiology of Taxus cells and is helpful to understand how MeJA elicits other plant species besides Taxus.

Integrating a comprehensive DNA barcode reference library with a global map of yews (Taxus L.) for forensic identification.

Science.gov (United States)

Liu, Jie; Milne, Richard I; Möller, Michael; Zhu, Guang-Fu; Ye, Lin-Jiang; Luo, Ya-Huang; Yang, Jun-Bo; Wambulwa, Moses Cheloti; Wang, Chun-Neng; Li, De-Zhu; Gao, Lian-Ming

2018-05-22

Rapid and accurate identification of endangered species is a critical component of bio-surveillance and conservation management, and potentially policing illegal trades. However, this is often not possible using traditional taxonomy, especially where only small or pre-processed parts of plants are available. Reliable identification can be achieved via a comprehensive DNA barcode reference library, accompanied by precise distribution data. However, these require extensive sampling at spatial and taxonomic scales, which has rarely been achieved for cosmopolitan taxa. Here we construct a comprehensive DNA barcode reference library, and generate distribution maps using species distribution modeling (SDM), for all 15 Taxus species worldwide. We find that trnL-trnF is the ideal barcode for Taxus: it can distinguish all Taxus species, and in combination with ITS identify hybrids. Among five analysis methods tested, NJ was the most effective. Among 4151 individuals screened for trnL-trnF, 73 haplotypes were detected, all species-specific and some population private. Taxonomical, geographical and genetic dimensions of sampling strategy were all found to affect the comprehensiveness of the resulting DNA barcode library. Maps from SDM showed that most species had allopatric distributions, except three in the Sino-Himalayan region. Using the barcode library and distribution map data, two unknown forensic samples were identified to species (and in one case, population) level, and another was determined as a putative interspecific hybrid. This integrated species identification system for Taxus can be used for bio-surveillance, conservation management and to monitor and prosecute illegal trade. Similar identification systems are recommended for other IUCN- and -CITES listed taxa. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Comparison of the safety and efficacy for application of (cypher)TM and (taxus)TM coronary stent in patients with coronary heart disease and concurrent diabetic

International Nuclear Information System (INIS)

Zhang Junjie; Chen Shaoliang; Chen Huaixin; Li Zhiheng; Lin Yanting

2005-01-01

Objective: To compare the relative safety and efficacy of Cypher and Taxus stent in coronary heart disease complicated with diabetes. Methods: A retrospective study of our hospital's Cardiology database containing one hundred and twenty-two CHD complicated with diabetes undergone selective or urgent implantation of DES stent between June 2002 and February 2004 were divided into Cypher stent group (n=31) and Taxus stent group (n=91). The endpoints included cardiac death ,myocardial infarction (MI) and TLR at 6-month. Results: 122 patients with majority of males (80%) and mean age of 56 ± 11 years. The baseline characteristics were similar in both groups. Majority lesions treated were consisted of AHA/ACC Type B2/C (75%). Compared to the Taxus group, the Cypher group had a smaller mean reference diameter (2.4±0.6 mm versus 2.6±0.7 mm, P TM and (Taxus) TM coronary stents are proved to be equally safe and effective with low rate of clinical restenosis, TLR and MACE at 6-month in coronary heart disease complicated with diabetes patients. (authors)

TAXOIDES: METABOLITOS SECUNDARIOS DEL ÁRBOL DEL TEJO (Taxus spp.

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Hebert J. Barrales-Cureño

2012-01-01

Full Text Available El árbol del tejo (Taxus spp. es una gimnosperma dicotiledónea que pertenece a la familia Taxaceae; se distribuye en America, Europa y Asia. Taxus spp. contiene en la corteza y en las hojas, alcaloides diterpénicos conocidos como taxoides. Éstos se caracterizan químicamente por la presencia de un esqueleto de taxano y un anillo de oxetano, tal como el taxol, que es utilizado en el tratamiento del cáncer de ovario, seno, próstata y pulmón; enfermedad que actualmente es una de las principales causas de muerte a nivel mundial. El contenido de taxol es bajo en los árboles, por tanto, es necesario el uso de alternativas biotecnológicas como lo es el cultivo in vitro de tejidos vegetales para incrementar la cantidad de taxoides y preservar el recurso natural. En esta revisión científica se reportan las características químicas de los taxoides, el mecanismo de acción biológico y semisíntesis orgánica del taxol, se detalla también la ruta biosintética de los principales taxoides, así como las principales enzimas involucradas para la obtención de éstos a nivel bioquímico y, finalmente, se indica de manera general la producción de taxoides en cultivos in vitro.

Assessment of the Mechanisms for Sr-90 and TRU Removal from Complexant-Containing Tank Wastes at Hanford

International Nuclear Information System (INIS)

Hallen, Richard T.; Geeting, John GH; Lilga, Michael A.; Hart, Todd R.; Hoopes, Francis V.

2005-01-01

Small-scale tests (∼20 mL) were conducted with samples from Hanford underground storage tanks AN-102 and AN-107 to assess the mechanisms for removing Sr-90 and transuranics (TRU) from the liquid (supernatant) portion of the waste. The Sr-90 and TRU must be removed (decontaminated), in addition to Cs-137 and the entrained solids, before the supernatant can be disposed of as low-activity waste. Experiments were conducted with various reagents and modified Sr/TRU removal process conditions to more fully understand the reaction mechanisms. The optimized treatment conditions--no added hydroxide, addition of Sr (0.02M target concentration) followed by sodium permanganate (0.02M target concentration) with mixing at ambient temperature--were used as a reference for comparison. The waste was initially two orders of magnitude undersaturated with Sr; the addition of nonradioactive Sr(NO?) ? saturated the supernatant, resulting in isotopic dilution and precipitation of Sr-90 as SrCO?. The reaction chemistry of Mn species relevant to the mechanism of TRU removal by permanganate treatment was evaluated, along with the importance of various mechanisms for decontamination, such as precipitation, absorption, ligand exchange, and oxidation of organic complexants. For TRU removal, permanganate addition generally gave the highest DF. The addition of Mn of lower oxidation states (II, IV, and VI) also resulted in good TRU removal, as did complexant oxidation with periodate and addition of Zr(IV) for ligand exchange. These results suggest that permanganate treatment leads to TRU removal by multiple routes

The dehydration of SrTeO3(H2O)--a topotactic reaction for preparation of the new metastable strontium oxotellurate(IV) phase ε-SrTeO3.

Science.gov (United States)

Stöger, Berthold; Weil, Matthias; Baran, Enrique J; González-Baró, Ana C; Malo, Sylvie; Rueff, Jean Michel; Petit, Sebastien; Lepetit, Marie Bernadette; Raveau, Bernard; Barrier, Nicolas

2011-05-28

Microcrystalline single-phase strontium oxotellurate(IV) monohydrate, SrTeO(3)(H(2)O), was obtained by microwave-assisted hydrothermal synthesis under alkaline conditions at 180 °C for 30 min. A temperature of 220 °C and longer reaction times led to single crystal growth of this material. The crystal structure of SrTeO(3)(H(2)O) was determined from single crystal X-ray diffraction data: P2(1)/c, Z = 4, a = 7.7669(5), b = 7.1739(4), c = 8.3311(5) Å, β = 107.210(1)°, V = 443.42(5) Å(3), 1403 structure factors, 63 parameters, R[F(2)>2σ(F(2))] = 0.0208, wR(F(2) all) = 0.0516, S = 1.031. SrTeO(3)(H(2)O) is isotypic with the homologous BaTeO(3)(H(2)O) and is characterised by a layered assembly parallel to (100) of edge-sharing [SrO(6)(H(2)O)] polyhedra capped on each side of the layer by trigonal-prismatic [TeO(3)] units. The cohesion of the structure is accomplished by moderate O-H···O hydrogen bonding interactions between donor water molecules and acceptor O atoms of adjacent layers. In a topochemical reaction, SrTeO(3)(H(2)O) condensates above 150 °C to the metastable phase ε-SrTeO(3) and transforms upon further heating to δ-SrTeO(3). The crystal structure of ε-SrTeO(3), the fifth known polymorph of this composition, was determined from combined electron microscopy and laboratory X-ray powder diffraction studies: P2(1)/c, Z = 4, a = 6.7759(1), b = 7.2188(1), c = 8.6773(2) Å, β = 126.4980(7)°, V = 341.20(18) Å(3), R(Fobs) = 0.0166, R(Bobs) = 0.0318, Rwp = 0.0733, Goof = 1.38. The structure of ε-SrTeO(3) shows the same basic set-up as SrTeO(3)(H(2)O), but the layered arrangement of the hydrous phase transforms into a framework structure after elimination of water. The structural studies of SrTeO(3)(H(2)O) and ε-SrTeO(3) are complemented by thermal analysis and vibrational spectroscopic measurements.

Climatic factors, genetic structure and phenotypic variation in English yew (Taxus baccata L.)

OpenAIRE

Mayol, Maria; Berganzo, Elisa; Burgarella, Concetta; González-Martínez, Santiago C.; Grivet, Delphine; Vendramin, Giovanni G.; Vincenot, Lucie; Riba, Miquel

2018-01-01

Influence of climatic factors on genetic structure and phenotypic variation in English yew (Taxus baccata L.) Conference "Adapting to global change in the Mediterranean hotspot" (Seville, 18-20 September 2013) Mediterranean forests constitute long-term reservoirs of biodiversity and adaptive potential. As compared with their central or northern European counterparts, Mediterranean forests are characterized by highly heterogeneous and fragmented environments, ...

Stellar laboratories . IX. New Se v, Sr iv-vii, Te vi, and I vi oscillator strengths and the Se, Sr, Te, and I abundances in the hot white dwarfs G191-B2B and RE 0503-289

Science.gov (United States)

Rauch, T.; Quinet, P.; Knörzer, M.; Hoyer, D.; Werner, K.; Kruk, J. W.; Demleitner, M.

2017-10-01

Context. To analyze spectra of hot stars, advanced non-local thermodynamic equilibrium (NLTE) model-atmosphere techniques are mandatory. Reliable atomic data is crucial for the calculation of such model atmospheres. Aims: We aim to calculate new Sr iv-vii oscillator strengths to identify for the first time Sr spectral lines in hot white dwarf (WD) stars and to determine the photospheric Sr abundances. To measure the abundances of Se, Te, and I in hot WDs, we aim to compute new Se v, Te vi, and I vi oscillator strengths. Methods: To consider radiative and collisional bound-bound transitions of Se v, Sr iv - vii, Te vi, and I vi in our NLTE atmosphere models, we calculated oscillator strengths for these ions. Results: We newly identified four Se v, 23 Sr v, 1 Te vi, and three I vi lines in the ultraviolet (UV) spectrum of RE 0503-289. We measured a photospheric Sr abundance of 6.5+ 3.8-2.4× 10-4 (mass fraction, 9500-23 800 times solar). We determined the abundances of Se (1.6+ 0.9-0.6× 10-3, 8000-20 000), Te (2.5+ 1.5-0.9× 10-4, 11 000-28 000), and I (1.4+ 0.8-0.5× 10-5, 2700-6700). No Se, Sr, Te, and I line was found in the UV spectra of G191-B2B and we could determine only upper abundance limits of approximately 100 times solar. Conclusions: All identified Se v, Sr v, Te vi, and I vi lines in the UV spectrum of RE 0503-289 were simultaneously well reproduced with our newly calculated oscillator strengths. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26666. Based on observations made with the NASA-CNES-CSA Far Ultraviolet Spectroscopic Explorer. Full Tables A.15 to A.21 are only available via the German Astrophysical Virtual Observatory (GAVO) service TOSS (http://dc.g-vo.org/TOSS).

Biological response of Sr-containing coating with various surface treatments on titanium substrate for medical applications

Energy Technology Data Exchange (ETDEWEB)

Yang, Shih-Ping [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China); Lee, Tzer-Min, E-mail: tmlee@mail.ncku.edu.tw [Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan (China); School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Lui, Truan-Sheng [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China)

2015-08-15

Graphical abstract: - Highlights: • Sr-containing coating prepared by plasma spraying and micro-arc oxidation process, respectively. • MAO coating stimulated high ECM-like structures of cells on early stage. • Sr-containing specimens had high cell responses on late stage. • Sr-MAO coating is a desirable implant surface treatment for clinical applications. - Abstract: An implant requires a suitable surface to trigger osteointegration. The surface characteristics and chemical composition are important factors in this process. Plasma spraying and micro-arc oxidation can be used to fabricate rough and porous structures for medical applications. Strontium (Sr) has been shown to prevent osteoporosis in vitro and in vivo. However, few scientists have evaluated the biological response of Sr-containing coatings on different surface treatments. In this study, a sand-blasted (SB) surface (as the control), plasma-sprayed hydroxyapatite (HA) and Sr-substituted HA coatings (HAPS and SrHAPS, respectively), calcium phosphate and Sr-containing calcium phosphate micro-arc oxidation surface (CPM and SrCPM, respectively) were analyzed in terms of human osteoblastic cell (MG63) response. Sr was confirmed to be incorporated into the surface. SrHAPS and SrCPM specimens had higher cell responses than those of the HAPS and CPM groups, respectively. The cells cultured on SrCPM and SrHAPS specimens exhibited high proliferation and differentiation. However, CPM and SrCPM specimens stimulated more ECM-like structures than other specimens. The results show that Sr-containing coatings have good characteristics that enhance cell response. The SrCPM coating is a suitable implant surface treatment for clinical applications.

Biological response of Sr-containing coating with various surface treatments on titanium substrate for medical applications

International Nuclear Information System (INIS)

Yang, Shih-Ping; Lee, Tzer-Min; Lui, Truan-Sheng

2015-01-01

Graphical abstract: - Highlights: • Sr-containing coating prepared by plasma spraying and micro-arc oxidation process, respectively. • MAO coating stimulated high ECM-like structures of cells on early stage. • Sr-containing specimens had high cell responses on late stage. • Sr-MAO coating is a desirable implant surface treatment for clinical applications. - Abstract: An implant requires a suitable surface to trigger osteointegration. The surface characteristics and chemical composition are important factors in this process. Plasma spraying and micro-arc oxidation can be used to fabricate rough and porous structures for medical applications. Strontium (Sr) has been shown to prevent osteoporosis in vitro and in vivo. However, few scientists have evaluated the biological response of Sr-containing coatings on different surface treatments. In this study, a sand-blasted (SB) surface (as the control), plasma-sprayed hydroxyapatite (HA) and Sr-substituted HA coatings (HAPS and SrHAPS, respectively), calcium phosphate and Sr-containing calcium phosphate micro-arc oxidation surface (CPM and SrCPM, respectively) were analyzed in terms of human osteoblastic cell (MG63) response. Sr was confirmed to be incorporated into the surface. SrHAPS and SrCPM specimens had higher cell responses than those of the HAPS and CPM groups, respectively. The cells cultured on SrCPM and SrHAPS specimens exhibited high proliferation and differentiation. However, CPM and SrCPM specimens stimulated more ECM-like structures than other specimens. The results show that Sr-containing coatings have good characteristics that enhance cell response. The SrCPM coating is a suitable implant surface treatment for clinical applications

Magnetoelectric Response in Multiferroic SrFe12O19 Ceramics.

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Guolong Tan

Full Text Available We report here realization of ferroelectricity, ferromagnetism and magnetocapacitance effect in singleSrFe12O19ceramic at room temperature. The ceramics demonstrate a saturated polarization hysteresis loop, two nonlinear I-V peaks and large anomaly of dielectric constant near Curie temperature, which confirm the intrinsic ferroelectricity of SrFe12O19 ceramicswith subsequent heat-treatment in O2atmosphere. The remnant polarization of the SrFe12O19 ceramic is estimated to be 103μC/cm2. The ceramic also exhibits strong ferromagnetic characterization, the coercive field and remnant magnetic moment are 6192Oe and 35.8emu/g, respectively. Subsequent annealing SrFe12O19 ceramics in O2 plays a key role on revealing its intrinsic ferroelectricity and improving the ferromagnetism through transforming Fe2+ into Fe3+. By applying a magnetic field, the capacitance demonstrates remarkable change along with B field, the maximum rate of change in ε (Δε(B/ε(0 is 1174%, which reflects a giant magnetocapacitance effect in SrFe12O19. XPS and molecular magnetic moment measurements confirmed the transformation of Fe2+ into Fe3+ and removal of oxygen vacancies upon O2 heat treatment. These combined functional responses in SrFe12O19 ceramics opens substantial possibilities for applications in novel electric devices.

Occurence of Cryptocline taxicola (All. Petr. on needles of Taxus spp. – symptoms and morphological features

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Ivana Šafránková

2008-01-01

Full Text Available In comparison with other European trees species Taxus spp. is not often prone to phytopathological problems. The fungus Cryptocline taxicola (All. Petr was found on needles of cultivars of Yet (T. baccata L., T. cuspidata S. & Z., Taxus × media Rehd. in Brno in the summer and the autumn of 2007. The article attemps to describe the disease symptoms and morphological features. Infected needles and whole shoots turn brown. Fruiting bodies were observed on upper and lower surfaces necrotic and chlorotic needles. Acervuli of the fungus were black, subepidermal, ∅ 160–370 × 90–145 μm, surrounded by brown circles epidermis, and the epidermis ruptures as they brake through. Conidia were smooth-walled and hyaline, without septa, ellipsoid to oval, 10–18 × 4,5–8,4 μm. Conidiophores were hyaline, cylindrical, with phyalides, 12–18 × 2,8–3,4 μm. The fungus forms dark colonies wish greyish aerial mycelium on potato-dextrose agar (PDA.

Randomized comparison between intracoronary β-radiation brachytherapy and implantation of paclitaxel-eluting stents for the treatment of diffuse in-stent restenosis

International Nuclear Information System (INIS)

Schukro, Christoph; Syeda, Bonni; Kirisits, Christian; Schmid, Rainer; Pichler, Philipp; Pokrajac, Boris; Lang, Irene; Poetter, Richard; Glogar, Dietmar

2007-01-01

Background and purpose: Intracoronary brachytherapy was the primary therapeutic option for the treatment of in-stent restenosis (ISR) during the last years. Especially for the treatment of diffuse ISR (lesions >10 mm), β-source brachytherapy was significantly superior to singular balloon angioplasty. Despite lacking clinical database, the implantation of drug eluting stents recently became a common procedure for the treatment of ISR. This randomized trial aimed to compare the efficacy of β-brachytherapy with β-radioisotopes 90 Sr/ 90 Y and paclitaxel-eluting stent implantation for the treatment of diffuse ISR. Material and methods: Thirty-seven patients with diffuse ISR were randomly assigned to β-brachytherapy after balloon angioplasty (Beta-Cath TM in 17 patients) or paclitaxel-eluting stent implantation (Taxus-Express2 TM in 20 patients). Six-month clinical follow-up was obtained for all patients, while angiographic follow-up was available for 30 patients. Results: Binary ISR (restenosis >50%) within target segment was observed in three patients treated with Beta-Cath TM , of which one needed target segment revascularisation for recurrent ISR, whereas no significant restenosis occurred in the patients treated with Taxus-Express2 TM (P = 0.037). No further major adverse cardiac (target segment revascularisation, myocardial infarction, death) was found in either group (P = NS). Stent implantation was the more time-saving (31 ± 11 min versus 60 ± 23 min, P TM arm, we found no difference in clinical outcome after implantation of paclitaxel-eluting stents for the treatment of diffuse ISR when compared to β-brachytherapy

Analysis of taxines in Taxus plant material and cell cultures by hplc photodiode array and hplc-electrospray mass spectrometry

NARCIS (Netherlands)

Theodoridis, G.; Laskaris, G.; Rozendaal, E.L.M.; Verpoorte, R.

2001-01-01

A semi-purified Taxus baccata needles extract was analysed by RP-HPLC. More than 18 taxines and cinnamates were detected by photodiode array detection and LC-MS, 10 of them being positively identified. Furthermore, 10-deacetyl baccatin III (paclitaxel's main precursor) and other taxanes were also

Immunoaffinity chromatography for the sample pretreatment of Taxus plant and cell extracts prior to analysis of taxanes by high-performance liquid chromatography

NARCIS (Netherlands)

Theodoridis, G; Haasnoot, W; Schilt, R; Jaziri, M; Diallo, B; Papadoyannis, IN; de Jong, GJ; Cazemier, G.

2002-01-01

The application of immunoaffinity chromatography for the purification of Taxus plant and cell extracts prior to the HPLC analysis is described. Polyclonal antibodies raised against 10-deacetylbaccatin III (10-DAB III), paclitaxel's main precursor in plant, were characterised by enzymed-linked

Adsorption of Some Hazardous Radionuclides on Cerium(IV) Antimonate

International Nuclear Information System (INIS)

Aly, H.F.; Zakaria, E.S.; Shady, S.A.; El-Naggar, I.M.

1999-01-01

Cerium(IV) antimonate had been prepared by the dropwise addition of 0.6 M antimony pentachloride and 0.6 M cerium ammonium nitrate solutions by a molar radio of Ce/Sb 0.75. Exchange isotherms for H +/ Co 2+ , H +/ Cs +, H +/ Zn 2+ , H +/ Sr 2+ and H +/ Eu 3+ have been determined at 25, 40 and 60 degree. Besides it was proved that europium is physically adsorbed while zinc, strontium, cobalt and cesium are chemically adsorbed. Moreover, the heat of adsorption of zinc, strontium, cobalt and cesium on cerium(IV) antimonate had been calculated and indicated that cerium(IV) antimonate is of endothermic behaviour towards these ions. Also the distribution coefficients of these ions were determined and it was found that the selectivity in the order: Eu 3+ >Sr 2+ > Cs +> Na +

Una revisión sobre la producción de taxoides anticancerígenos en cultivos in vitro de callos y células de Taxus spp.

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Hebert Jair Barrales Cureño

2013-07-01

Palabras clave: cáncer, biotecnología, metabolismo secundario, taxol, Taxaceae.  Abstract: The taxoids are polioxigenated diterpenes from the metabolic pathway of the 2-methyl-erythritol 4-phosphate whose biosynthesis is generated in the plastides. The importance of the taxoides including taxol, in the area of human medicine is very valuable due to the use in oncology, drug used against breast, lung and ovarian cancer. The species of trees of Taxus spp. are in danger of extinction due to logging immoderate, to the low reproduction rate, slow growth; therefore, the plant tissue culture in vitro is a biotechnological alternative high-impact and a great help to the knowledge of the production of the taxoides to level in vitro and above all, for the conservation of this valuable natural resource. The objectives of this article are to determine some general information about the geographical distribution of Taxus spp.; chemical characteristics of taxoids, biological mechanism of action of taxol; path of biosynthesis, methods of extraction and analysis of the taxoids and a current review of the production of taxoids in situ and in vitro cultures and cells of Taxus spp.  Key words: cancer, biotechnology, secondary metabolism, taxol, Taxaceae.

Underutilization of IV nitrates in the treatment of acute heart failure.

Science.gov (United States)

Mohan, Mohapradeep; Hawkey, Sean; Baig, Fatima; Choy, Anna Maria; Lang, Chim C

2015-08-01

Acute heart failure (AHF) is a growing public health concern with high inhospital mortality and costs. Clinical practice guidelines, underpinned by positive randomized controlled trials, recommend the early use of intravenous (IV) nitrates in the treatment of AHF. However, the "real-world" usage of IV nitrates has not been clearly defined. The objective of this study was to examine the use of IV nitrates in the treatment of AHF as recommended by clinical practice guidelines. A case-record analysis was conducted of all admissions with AHF at a large teaching hospital. Of the 81 AHF patients (mean age 77 ± 11, mean SBP 130 ± 27 mmHg) enrolled for this analysis, only 5 (6%) received IV nitrates at the time of AHF admission. Forty (49%, mean age 77 ± 11, mean SBP 131 ± 27 mmHg) of these 81 patients met the guideline criteria for suitability for IV nitrates and only 5 (12%) of these received them during this admission. Patients who received IV nitrates were more likely to have higher blood pressure and all had myocardial ischemia as a precipitant. Seventy-five (93%) of the total population received loop diuretics on admission. Overall, this study shows that loop diuretics remain the first-line therapy in AHF with little use of IV nitrates, despite recommendations from clinical practice guidelines. © 2015 John Wiley & Sons Ltd.

The Sr-90 waste treatment by using sodium carbonat as a carrier

International Nuclear Information System (INIS)

Suroto.

1978-01-01

The coprecipitation processes of the Sr-90 wastes, with the lime-soda treatment, that followed by the mechanism of isomorph substitution, have shown a good performance in pH 7-8. Excess of natrium carbonate in the lime-soda treatment caused the decrease of the decontamination factor. This research shows that the coprecipitation by calcite-phosphate was better than the lime-soda treatment. (author)

Solving the Issue of Restenosis After Stenting of Intracranial Stenoses: Experience with Two Thin-Strut Drug-Eluting Stents (DES)—Taxus Element™ and Resolute Integrity™

Energy Technology Data Exchange (ETDEWEB)

Kurre, Wiebke, E-mail: wiebke.kurre@gmx.de; Aguilar-Pérez, Marta [Klinikum Stuttgart, Klinik für Diagnostische und Interventionelle Neuroradiologie (Germany); Fischer, Sebastian [Universitätsklinikum Knappschaftskrankenhaus Bochum GmbH, Institut für Diagnostische und Interventionelle Radiologie, Neuroradiologie und Nuklearmedizin (Germany); Arnold, Guy [Klinikverbund Südwest, Klinikum Sindelfingen, Klinik für Neurologie (Germany); Schmid, Elisabeth; Bäzner, Hansjörg [Klinikum Stuttgart, Klinik für Neurologie (Germany); Henkes, Hans [Klinikum Stuttgart, Klinik für Diagnostische und Interventionelle Neuroradiologie (Germany)

2015-06-15

PurposeThin-strut, flexible DES are suitable for intracranial stenting and may improve long-term vessel patency. The purpose of this study was to report our experience with two new-generation DES for the treatment of intracranial atherosclerotic disease.Patients and MethodsWe retrospectively reviewed all patients treated with Taxus Element™ or Resolute Integrity™ stent for an intracranial atherosclerotic stenosis between March 2011 and August 2013. Technical success was defined as the ability to deploy the device at the desired location and reduce the degree of stenosis below 50 %. All procedure-related strokes were recorded. Control angiography was scheduled after 6 weeks, 3, 6, and 12 months and yearly thereafter. A luminal narrowing ≥50 % was regarded as a restenosis. Stroke recurrence in the territory of the treated artery was reported.ResultsIn the defined period we treated 101 patients harboring 117 intracranial stenoses. The procedure was successful in 100 (85.5 %) lesions. Procedure-related strokes occurred in 10 (9.9 %) patients with a permanent morbidity in 3 (3.0 %). Follow-up angiography was available for 83 of 100 (83.0 %) successfully treated lesions with an average of 355 days (IQR 153–482 days). Three (3.6 %) asymptomatic restenoses were detected. All occurred after treatment with Resolute Integrity™, none after Taxus Element™ (p = 0.059). New strokes in the territory of the treated artery were encountered in 2 (2.6 %) occasions.ConclusionThin-strut DES improve long-term patency and reduce the risk of subsequent stroke. Differences between devices may exist. Feasibility is comparable to bare-metal balloon-mounted stents and procedure-related strokes occurred within the expected range.

Development and characterization of microsatellite loci in the endangered species Taxus wallichiana (Taxaceae).

Science.gov (United States)

Gajurel, Jyoti Prasad; Cornejo, Carolina; Werth, Silke; Shrestha, Krishna Kumar; Scheidegger, Christoph

2013-03-01

Microsatellite primers were developed in the endangered tree species Taxus wallichiana from Nepal to investigate regional genetic differentiation, local genetic diversity, and gene flow for the conservation of this species under climate- and land-use change scenarios in mountain regions of Nepal. • We developed 10 highly polymorphic microsatellite markers from 454 DNA sequencing. Characterization of the new microsatellite loci was done in 99 individuals collected from three valleys with different climatic regimes. The number of alleles per locus varied from four to 12. Observed heterozygosity of populations, averaged across loci, ranged from 0.30 to 0.59. • The new markers provided by this study will substantially increase the resolution for detailed studies in phylogeography, population genetics, and parentage analysis.

Slippery when sticky: Lubricating properties of thin films of Taxus baccata aril mucilage

DEFF Research Database (Denmark)

Røn, Troels; Sankaranarayanan, Rishikesan; Chronakis, Ioannis S.

2016-01-01

Mucilage is hydrogel produced from succulent plants and microorganisms displaying unique adhesiveness and slipperiness simultaneously. The objective of this study is to establish an understanding on the lubricating mechanisms of the mucilage from Taxus baccata aril as thin, viscous lubricant films....... Oscillation and flow rheological studies revealed that T. baccata mucilage is shear-thinning, thixotropic, and weak hydrogel that is highly stretchable under shear stress due to its high density physical crosslinking characteristics. In addition, T. baccata mucilage showed a distinct Weissenberg effect, i...... effectively manifested at soft, hydrophilic, and rolling tribological contacts. Based on tenacious spreading on highly wettingsurfaces, slip plane can be formed within mucilage hydrogel network even when the lubricating films cannot completely separate the opposing surfaces. Moreover, highly stretchable...

Bioactive Constituents from an Endophytic Fungus, Penicillium polonicum NFW9, Associated with Taxus fauna.

Science.gov (United States)

Fatima, Nighat; Sripisut, Tawanun; Youn, Ui J; Ahmed, Safia; Ul-Haq, Ihsan; Munoz-Acuna, Ulyana; Simmons, Charles J; Qazi, Muneer A; Jadoon, Muniba; Tan, Ghee T; de Blanco, Esperanza J C; Chang, Leng C

2017-01-01

Endophytic fungi are being recognized as vital and untapped sources of a variety of structurally novel and unique bioactive secondary metabolites in the field of natural products drug discovery. Herein, this study reports the isolation and characterization of secondary metabolites from an endophytic fungus Penicillium polonicum (NFW9) associated with Taxus fuana. The extracts of the endophytic fungus cultured on potato dextrose agar were purified using several chromatographic techniques. Biological evaluation was performed based on their abilities to inhibit tumor necrosis factor-alpha (TNF-α)-induced nuclear factor-kappa B (NF-κB) and cytotoxicity assays. Bioactivity-directed fractionation of the ethyl acetate extract of a fermentation culture of an endophytic fungus, Penicillium polonicum led to the isolation of a dimeric anthraquinone, (R)- 1,1',3,3',5,5'-hexahydroxy-7,7'-dimethyl[2,2'-bianthracene]-9,9',10,10'-tetraone (1), a steroidal furanoid (-)-wortmannolone (2), along with three other compounds (3-4). Moreover, this is the first report on the isolation of compound 1 from an endophytic fungus. All purified metabolites were characterized by NMR and MS data analyses. The stereo structure of compound 1 was determined by the measurement of specific optical rotation and CD spectrum. The relative stereochemistry of 2 was confirmed by single-crystal X-ray diffraction. Compounds 2-3 showed inhibitory activities in the TNF-α-induced NF-κB assay with IC50 values in the range of 0.47-2.11 µM. Compounds 1, 4 and 5 showed moderate inhibition against NF-κB and cancer cell lines. The endophytic fungus Penicillium polonicum of Taxus fuana is capable of producing biologically active natural compounds. Our results provide a scientific rationale for further chemical investigations into endophyte-producing natural products, drug discovery and development. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Improved oral bioavailability in rats of SR13668, a novel anti-cancer agent.

Science.gov (United States)

Green, Carol E; Swezey, Robert; Bakke, James; Shinn, Walter; Furimsky, Anna; Bejugam, Naveen; Shankar, Gita N; Jong, Ling; Kapetanovic, Izet M

2011-05-01

SR13668, a bis-indole with potent activity in vitro and in vivo against various cancers and promising cancer chemopreventive activity, was found to have very low oral bioavailability, <1%, in rats during pilot pharmacokinetic studies. The objective of these studies was to better understand the source of low oral exposure and to develop a formulation that could be used in preclinical development studies. An automated screening system for determining solubility in lipid-based vehicles, singly and in combination, was used to identify formulations that might enhance absorption by improving solubility of SR13668, and these results were confirmed in vivo using Sprague-Dawley rats. Pharmacokinetics of SR13668 was then determined in male and female Sprague-Dawley rats administered 1 mg/kg iv, 1, 10, and 30 mg/kg po formulated in PEG400:Labrasol (1:1 v/v). Blood was collected at time points through 24 h and the concentration of SR13668 determined using HPLC with UV and fluorescence detection. SR13668 was found to be resistant to plasma esterases in vitro and relatively stable to rat and human liver microsomal metabolism. SR13668 concentrates in tissues as indicated by significantly higher levels in lung compared to blood, blood concentrations ~2.5-fold higher than plasma levels, and apparent volume of distribution (V) of ~5 l/kg. A marked sex difference was observed in exposure to SR13668 with area under the curve (AUC) significantly higher and clearance (CL) lower for female compared to male rats, after both iv and oral administration. The oral bioavailability (F) of SR13668 was 25.4 ± 3.8 and 27.7 ± 3.9% (30 mg/kg), for males and females, respectively. A putative metabolite (M1), molecular weight of 445 in the negative ion mode (i.e., SR13668 + 16), was identified in blood samples from both the iv and po routes, as well as in vitro microsomal samples. In summary, while SR13668 does undergo metabolism, probably by the liver, the oral bioavailability of SR13668 in rats

Development and Characterization of Microsatellite Loci in the Endangered Species Taxus wallichiana (Taxaceae

Directory of Open Access Journals (Sweden)

Jyoti Prasad Gajurel

2013-03-01

Full Text Available Premise of the study: Microsatellite primers were developed in the endangered tree species Taxus wallichiana from Nepal to investigate regional genetic differentiation, local genetic diversity, and gene flow for the conservation of this species under climate- and land-use change scenarios in mountain regions of Nepal. Methods and Results: We developed 10 highly polymorphic microsatellite markers from 454 DNA sequencing. Characterization of the new microsatellite loci was done in 99 individuals collected from three valleys with different climatic regimes. The number of alleles per locus varied from four to 12. Observed heterozygosity of populations, averaged across loci, ranged from 0.30 to 0.59. Conclusions: The new markers provided by this study will substantially increase the resolution for detailed studies in phylogeography, population genetics, and parentage analysis.

Single i.v. ketamine augmentation of newly initiated escitalopram for major depression: results from a randomized, placebo-controlled 4-week study.

Science.gov (United States)

Hu, Y-D; Xiang, Y-T; Fang, J-X; Zu, S; Sha, S; Shi, H; Ungvari, G S; Correll, C U; Chiu, H F K; Xue, Y; Tian, T-F; Wu, A-S; Ma, X; Wang, G

2016-02-01

While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD). Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾ 24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery-Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology - Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾ 50% MADRS score reduction) was the primary outcome. By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01-0.22, p escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days-2 weeks; effect size (ES) = 1.08-1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation. Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up

Therapeutic result of radioactive nuclide 90Sr/90Y treatment in patients with benign prostatic hypertrophy (BPH)

International Nuclear Information System (INIS)

Chen Hanchao; Li Yuying

2008-01-01

Objective: To study the effect of radioactive nuclide 90 Sr/ 90 Y treatment in patients with benign prostatic hypertrophy (BPH). Methods: Sixty patients with BPH were treated with a course of transurethral radioactive nuclide 90 Sr/ 90 Y therapy. Results: The severity of BPH was assessed with four parameters: maximal flow rate (MFR), volume of residual urine (VRU), international prostatic symptom score (IPSS) and volume (size) of prostate. In this series, the total effective rate was 93.33% with no treatment- related mortality. Favorable changes of the parameters after a course of radioactive nuclide therapy were significant. Conclusion: Radioactive nuclide 90 Sr/ 90 Y therapy for patients with BPH was safe, easily performed and quite effective. This procedure is worth popularizing in appropriate patients. (authors)

Meta-Analysis of Treatment Outcomes Measured by the Y-OQ and Y-OQ-SR Comparing Wilderness and Non-Wilderness Treatment Programs

Science.gov (United States)

Gillis, Harold L.; Speelman, Elizabeth; Linville, Noelle; Bailey, Emily; Kalle, Ashley; Oglesbee, Nathan; Sandlin, James; Thompson, Lauren; Jensen, Jennifer

2016-01-01

Background: Monitoring youth treatments requires outcome instruments sensitive to change. The Y-OQ and the Y-OQ-SR measure behavioral change during psychological treatment. Objective: The focus of this study was to compare treatment progress of youth in studies using the Youth Outcome Questionnaire (YOQ) or the Youth Outcome Questionnaire Self…

Alogliptin, a potent and selective dipeptidyl peptidase-IV inhibitor for the treatment of type 2 diabetes

DEFF Research Database (Denmark)

Deacon, Carolyn F

2008-01-01

Takeda San Diego Inc is developing alogliptin, a small-molecule, orally available dipeptidyl peptidase IV (DPP IV) inhibitor, for the potential treatment of type 2 diabetes. In January 2008, Takeda announced that an NDA for alogliptin had been submitted to the FDA.......Takeda San Diego Inc is developing alogliptin, a small-molecule, orally available dipeptidyl peptidase IV (DPP IV) inhibitor, for the potential treatment of type 2 diabetes. In January 2008, Takeda announced that an NDA for alogliptin had been submitted to the FDA....

Clinical observation of 89Sr treatment efficacy of multiple bone metastases in breast and prostate cancer patients

International Nuclear Information System (INIS)

Yuan Chao; Li Weipeng; Hu Yongquan; Tao Jian

2010-01-01

Objective: To evaluate the efficacy of 89 Sr in treatment of multiple bone metastases of breast and prostate cancer patients. Methods: Seventy multiple bone metastases patients (30 females with breast cancer and 40 males with prostate cancer) were treated with 89 Sr. The clinical effectiveness was assessed by Karnofsky performance score and whole body bone scanning data. Results: The total pain relief rate was 79% in bone metastases of breast cancer and 85% in bone metastases of prostate cancer, respectively. There was no significant differences between the two groups (χ 2 =0.78, P>0.05). The Karnofsky score was significantly improved in both groups (t=2.46, P 89 Sr treatment was good, and the quality of life was improved in patients with multiple bone metastases breast or prostate cancer. (authors)

Sensitization by SR-2508 plus Ro 03-8799

International Nuclear Information System (INIS)

Stone, H.B.; Luu, Y.H.; Lam, K.N.

1986-01-01

The primary toxicity of Ro 03-8799 is a central nervous system toxicity, whereas that of SR-2508 is a peripheral neuropathy. The feasibility of reducing overall toxicity while maintaining maximal radiosensitization by using the two sensitizers together was tested. The LD50/2 of Ro 03-8799 was 0.68 mg/g body wt (mg/gbw) after intravenous (i.v.) administration, and that of SR-2508 was 4.4 mg/gbw after i.v. administration. When both drugs were given together in equitoxic proportions, the LD50/2 was 0.45 mg of Ro 03-8799 plus 2.9 mg of SR-2508/gbw. These doses are 66% of the respective LD50/2 values of the drugs when given separately. Radiosensitization was evaluated using in vivo-in vitro assays with EMT6/SF tumors in BALB/c mice. At drug doses between 10 and 60% of the LD50/2, sensitization was generally maximal and similar to that from misonidazole, but there was less sensitization below this dose, both with the drugs given separately and together. If chronic toxicities of these drugs overlap as do the acute toxicities there will be little or no additional benefit from using these drugs in combination, compared to using them separately

Immunohistochemical Analysis of Collagen IV and Laminin Expression in Spontaneous Melanoma Regression in the Melanoma-Bearing Libechov Minipig

International Nuclear Information System (INIS)

Planska, Daniela; Burocziova, Monika; Strnadel, Jan; Horak, Vratislav

2015-01-01

Spontaneous regression (SR) of human melanoma is a rare, well-documented phenomenon that is not still fully understood. Its detailed study cannot be performed in patients due to ethical reasons. Using the Melanoma-bearing Libechov Minipig (MeLiM) animals of various ages (from 3 weeks to 8 months) we implemented a long-term monitoring of melanoma growth and SR. We focused on immunohistochemical detection of two important extracellular matrix proteins, collagen IV and laminin, which are associated with cancer. We showed that SR of melanoma is a highly dynamic process. The expression of collagen IV and laminin correlated with changes in population of melanoma cells. Tumours of 3-week-old animals consisted primarily of melanoma cells with a granular expression of collagen IV and laminin around them. Thereafter, melanoma cells were gradually destroyed and tumour tissue was rebuilt into the connective tissue. Collagen IV expression slightly increased in tumours of 10-week-old pigs showing extracellular fibrous appearance. In tumours of older animals, areas lacking melanoma cells demonstrated a low expression and areas still containing melanoma cells a high expression of both proteins. We considered the age of 10 weeks as a turning point in the transition between tumour growth and SR of the MeLiM melanoma

DNA and Flavonoids Leach out from Active Nuclei of Taxus and Tsuga after Extreme Climate Stresses

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Walter Feucht

2015-09-01

Full Text Available Severe over-stresses of climate caused dramatic changes in the intracellular distribution of the flavonoids. This was studied in needles from the current year’s growth of the following species and varieties: Tsuga canadensis, Taxus baccata, T. aurea, T. repens, T. nana, and T. compacta. The mode of steady changes in flavonoids was evaluated by microscopic techniques. Most of the flavonoids stain visibly yellow by themselves. The colorless flavanol subgroup can be stained blue by the DMACA reagent. In mid-summer 2013, outstanding high temperatures and intense photo-oxidative irradiation caused in a free-standing tree of Taxus baccata dramatic heat damage in a limited number of cells of the palisade layers. In these cells, the cytoplasm was burned brown. However, the nucleus maintained its healthy “blue” colored appearance which apparently was a result of antioxidant barrier effects by these flavanols. In late May 2014, excessive rainfall greatly affected all study trees. Collectively, in all study trees, a limited number of the mesophyll nuclei from the needless grown in 2013 and 2014 became overly turgid, enlarged in size and the flavanols leached outward through the damaged nuclear membranes. This diffusive stress event was followed one to three days later by a similar efflux of DNA. Such a complete dissolution of the nuclei in young tissues was the most spectacular phenomenon of the present study. As a common feature, leaching of both flavanols and DNA was markedly enhanced with increasing size and age of the cells. There is evidence that signalling flavonoids are sensitized to provide in nuclei and cytoplasm multiple mutual protective mechanisms. However, this well-orchestrated flavonoid system is broken down by extreme climate events.

The accumulation and elimination of 89Sr in tea leaves

International Nuclear Information System (INIS)

Zhang Yongxi; Wang Shouxiang; Chen Chuanqun; Sun Zhiming; Hu Bingmin; Huang Dan

1995-01-01

The 89 Sr was added to the tea tree-soil system by different ways. The 89 Sr in the system through the over-ground part of tea tree, was much more than that through soil. The 89 Sr concentration in older leaves was higher than in shoot for a definite treatment. The accumulation elimination law of 89 Sr in leaves varied with the treatments. For the treatment through the over-ground part, the 89 Sr concentration in older leaves and shoot was monotonously decreased with time increasing. But for the treatment through soil the 89 Sr concentration in shoot was increased to reach a peak value, and then decreased slowly; while the 89 Sr concentration in older leaves increased quickly in a period, then increased slowly to attain a saturated value. In addition, the concentration factor of 89 Sr in older leaves and shoot were determined

Treatment of Stage IV Non-small Cell Lung Cancer

Science.gov (United States)

Evans, Tracey; Gettinger, Scott; Hensing, Thomas A.; VanDam Sequist, Lecia; Ireland, Belinda; Stinchcombe, Thomas E.

2013-01-01

Background: Stage IV non-small cell lung cancer (NSCLC) is a treatable, but not curable, clinical entity in patients given the diagnosis at a time when their performance status (PS) remains good. Methods: A systematic literature review was performed to update the previous edition of the American College of Chest Physicians Lung Cancer Guidelines. Results: The use of pemetrexed should be restricted to patients with nonsquamous histology. Similarly, bevacizumab in combination with chemotherapy (and as continuation maintenance) should be restricted to patients with nonsquamous histology and an Eastern Cooperative Oncology Group (ECOG) PS of 0 to 1; however, the data now suggest it is safe to use in those patients with treated and controlled brain metastases. Data at this time are insufficient regarding the safety of bevacizumab in patients receiving therapeutic anticoagulation who have an ECOG PS of 2. The role of cetuximab added to chemotherapy remains uncertain and its routine use cannot be recommended. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors as first-line therapy are the recommended treatment of those patients identified as having an EGFR mutation. The use of maintenance therapy with either pemetrexed or erlotinib should be considered after four cycles of first-line therapy in those patients without evidence of disease progression. The use of second- and third-line therapy in stage IV NSCLC is recommended in those patients retaining a good PS; however, the benefit of therapy beyond the third-line setting has not been demonstrated. In the elderly and in patients with a poor PS, the use of two-drug, platinum-based regimens is preferred. Palliative care should be initiated early in the course of therapy for stage IV NSCLC. Conclusions: Significant advances continue to be made, and the treatment of stage IV NSCLC has become nuanced and specific for particular histologic subtypes and clinical patient characteristics and according to the

Room temperature transport properties of new BiSrCaCuO compounds; Proprietes de transport a la temperature ambiante de nouveaux composes BiSrCaCuO

Energy Technology Data Exchange (ETDEWEB)

Lagues, M.; Partiot, C.; Mairet, V.; Hatterer, C.; Xu, X.Z.; Deville Cavellin, C. [Laboratoire Surface et Supraconducteurs, Ecole Superieure de Physique et de Chimie Industrielle, CNRS UPR5, Universite Paris, 75 - Paris (France); Beuran, C.; Eustache, B.; Moussy, J.B. [Wintici SA, 94 - Vincennes (France)

1997-05-01

New compounds belonging to the BiSrCaCuO cuprate family have been synthesized by sequentially imposed layer epitaxy. The Cu/Ca ratio in these compounds is typically twice the value for conventional Bi{sub 2}Sr{sub 2}Ca{sub n-1}Cu{sub n+4}. A second characteristic of the new compounds is a Bi deficiency relative to conventional BSCCO. The room temperature electrical resistivity of these compounds reaches extremely low values, orders of magnitude below that of copper. Strongly non-linear I(V) characteristics of various forms are observed; Typical examples are describes where the voltage dependence at the onset of measurable dissipation is either exponential or parabolic as a function of current intensity. Examples are also presented I(V) exhibits and hysteric behavior. (authors). 51 refs.

A first order approximation of the tumor absorbed dose prior to treatment with Sr-89

International Nuclear Information System (INIS)

Manetou, A.; Toubanakis, N.; Lyra, M.; Lymouris, G.

1994-01-01

A new technique developed for the estimation of the absorbed dose prior to treatment with Sr-89 is presented. This technique implies that patient undergoes bone scanning with Tc-99m-MDP, two days before the administration of Sr-89. A number of sequential quantitative images are to be obtained over the first 8 hours after the Tc-99m-MDP injection and data are used to derive St-89 time retention curve. For the development of this technique a simplified model for the kinetics of both Sr-89 and Tc-99m-MDP was assumed. Data on the time retention of the two radiopharmaceuticals for a compartment including bone surface and bone space of trabecular and cortical bone for normal adults were combined together. A linear relationship was derived between the time required for the same percentage uptake of the two radiopharmaceuticals after single injection. The absorbed dose in the principal metastases and normal bone, of the same type and volume with the metastases, for two patients who were treated with Sr-89 for metastasized prostatic carcinoma are reported. (authors)

Extracorporeal life support and digoxin-specific Fab fragments for successful management of Taxus baccata intoxication with low output and ventricular arrhythmia.

Science.gov (United States)

Farag, Mina; Badowski, Dominika; Koschny, Ronald; Skopp, Gisela; Brcic, Andreas; Szabo, Gabor B

2017-12-01

Yew plants are evergreen shrubs which are widely spread throughout the northern hemisphere. Taxane alkaloid derivatives, mainly taxine B, represent the main toxins of Taxus baccata and are highly cardiotoxic. Due to the lack of randomized clinical trials, case reports on accidental or suicidal yew intoxications build the only source of knowledge of clinical treatment options. We report the case of a suicidal yew ingestion admitted to our hospital under prolonged cardiopulmonary resuscitation due to pulseless electrical activity. Extra-corporeal life support (ECLS) was established to maintain adequate organ perfusion. Repeated administration of digoxin-specific Fab antibody fragments, which cross-react with taxine, was associated with an immediate conversion from asystole to broad-complex bradycardia and a gradual normalization of the electrocardiogram (ECG). This was paralleled by a recovery of the cardiac function and weaning from the ECLS. The taxine metabolite 3,5-dimethoxyphenol could be detected by mass spectrometry before but not after the first Fab-fragment treatment. In contrast, the total amount of taxine (including the neutralized, Fab fragment-bound fraction) was increased after each Fab fragment administration, suggesting an accumulation of neutralized, since antibody-bound taxine in the blood by anti-digoxin Fab fragments. In conclusion, the successful clinical course of this case suggests a benefit of an early anti-digoxin Fab-fragment administration for the treatment of yew intoxication. Copyright © 2017 Elsevier Inc. All rights reserved.

The dynamics of accumulation and disappearance of 89Sr in tea

International Nuclear Information System (INIS)

Chen Chuanqun; Wang Shouxiang; Zhang Yongxi; Sun Zhiming

1994-06-01

The 89 Sr was put into a tea tree-soil system by different ways. The results showed that for 89 Sr put into the system through the above-ground 1 part of tea tree, its concentration in tea was much higher than that through soil. The concentration of 89 Sr in older tea was higher than that in shoot for the same treatment. The accumulation and disappearance of 89 Sr in tea varied with the treatments. For the treatment through the above-ground part, the concentrations of 89 Sr in older tea and shoot were monotonously decreasing with time. For the treatment through soil the concentration of 89 Sr in shoot increased initially to a maximum value, then decreased slowly; while the concentration of 89 Sr in older tea increased quickly in a definite period, then increased slowly to gain a saturated value. In addition, the values of concentration factor of 89 Sr in the older tea and shoot were determined, too

A review of expert judgement and treatment of probability in SR 97

International Nuclear Information System (INIS)

Wilmot, R.D.; Crawford, M.B.

2000-01-01

The Swedish Nuclear Fuel and Waste Management Company (SKB) recently published its latest performance assessment for deep disposal of spent nuclear fuel, based on the KBS-3 concept. This assessment, SR 97, uses three hypothetical repository sites (known as Aberg, Beberg and Ceberg) to provide a range of geological settings and hydrogeological conditions for the assessment. The long-term performance of these sites is compared for several sets of assumptions relating to canister lifetimes, climate evolution, and patterns of human behaviour. This report is a review of SR 97 conducted by Galson Sciences Ltd on behalf of the Swedish Nuclear Power Inspectorate (SKI). The review focussed on the use of expert judgement in the assessment and on the treatment of uncertainty and the use of probability in assessment calculations. The review of SR 97 concluded that SKB had identified many of the judgements made in developing and implementing the assessment and modelling approaches, but that a more formal documentation of the assumptions involved would add to the clarity and transparency of the use of judgements. Similarly, explicit acknowledgement of the basis for making judgements about the treatment of FEPs would improve confidence in the assessment. There are a number of tools that can be useful in justifying the judgements made in an assessment. The review concluded that more use of dialogue with stake holders, peer review and expert elicitation could all be of value in SKB's assessment programme. Recently introduced regulations in Sweden have established an individual risk criterion for the long-term performance of repositories. SKB has previously identified 'pessimistic' and 'reasonable' values for a number of model parameters, and used these in a range of deterministic calculations to calculate dose and to illustrate system performance. To allow for the calculation of risk, SKB introduced probabilistic analyses into the SR 97 assessment by assigning probabilities of 10

A first order approximation of the tumor absorbed dose prior to treatment with Sr-89

Energy Technology Data Exchange (ETDEWEB)

Manetou, A [NIMITS Hospital, Medical Physics Unit, Athens (Greece); Toubanakis, N; Lyra, M; Lymouris, G [Areteion University Hospital, Radiology Department, Athens (Greece)

1994-12-31

A new technique developed for the estimation of the absorbed dose prior to treatment with Sr-89 is presented. This technique implies that patient undergoes bone scanning with Tc-99m-MDP, two days before the administration of Sr-89. A number of sequential quantitative images are to be obtained over the first 8 hours after the Tc-99m-MDP injection and data are used to derive St-89 time retention curve. For the development of this technique a simplified model for the kinetics of both Sr-89 and Tc-99m-MDP was assumed. Data on the time retention of the two radiopharmaceuticals for a compartment including bone surface and bone space of trabecular and cortical bone for normal adults were combined together. A linear relationship was derived between the time required for the same percentage uptake of the two radiopharmaceuticals after single injection. The absorbed dose in the principal metastases and normal bone, of the same type and volume with the metastases, for two patients who were treated with Sr-89 for metastasized prostatic carcinoma are reported. (authors). 23 refs,3 figs, 2 tabs.

Effect of different treatments on 85Sr plant uptake in various soil types

International Nuclear Information System (INIS)

Koblinger-Bokori, E.; Szerbin, P.

2000-01-01

In the recent years radioecological studies are concentrated on the investigation of restoration possibilities of contaminated ecosystems. These studies are aimed to develop methods for decreasing the bioavailability of the radionuclides released to the environment. Radionuclides of long half-lives, such as 90 Sr and 137 Cs, are of special importance from the point of human health, since these nuclides can enter the human body via the food-chain and increase the radiation burden for many years. 90 Sr and 137 Cs contamination of the environment may occur as a result of atmospheric releases during nuclear accidents. For instance, considerable amounts were released to the atmosphere during the Chernobyl reactor accident. In the presented study strontium plant uptake from different types of soil was investigated. To avoid the difficulties related to 90 Sr determination, the gamma-emitting strontium isotope 85 Sr is used at the experiments (no isotopic effect takes place). The plant selected is yellow leguminous bean. Most typical Hungarian soils (leached Ramann brown forest soil, alluvial soil, chernozem-light sandy soil and calcareous chernozem soil) were selected for the experiments carried out under laboratory conditions. Results are presented in relation to major soil characteristics. Effects of two different treatments: lime and organic matter fertilizations on plant uptake are given. The highest uptake was found in bean grown on leached Ramann brown forest soil, whereas the lowest value was measured in the plant grown in calcareous chernozem soil. Organic fertilization significantly reduced the uptake of radiostrontium in all investigated types of soil. The largest factor of reduction was found to be as high as 3.5. Lime fertilization was less effective. Our study clearly demonstrates that carefully selected post-accident treatments (e.g. organic fertilization following strontium contamination) can significantly reduce the environmental consequences of

SR and LR Union Suture for the Treatment of Myopic Strabismus Fixus: Is Scleral Fixation Necessary?

Directory of Open Access Journals (Sweden)

Carol P. S. Lam

2015-01-01

Full Text Available Purpose. To evaluate and compare the effectiveness of scleral fixation SR and LR union suture and nonscleral fixation union suture for the treatment of myopic strabismus fixus. Methods. Retrospective review of 32 eyes of 22 patients with myopic strabismus fixus who had undergone union suture of superior rectus (SR and lateral rectus (LR with or without scleral fixation, and follow-up longer than 6 months at Hong Kong Eye Hospital from 2006 to 2013. Surgical techniques and outcomes in terms of ocular alignment are analyzed. Results. There is significant overall improvement both in postoperative angle of esodeviation (P0.05. Conclusions. Union suture of SR and LR is an effective procedure in correcting myopic strabismus fixus. Fixation of the union suture to the sclera does not improve surgical outcome.

Age influence on retention, distribution and internal doses of 85Sr in rat

International Nuclear Information System (INIS)

Tian Wuxun; Wang Decheng; Zhang Hongyuan

1990-01-01

After I.V. 85 Sr, the whole body 85 Sr-retentions in rats were fit to two compartment exponential equations. The equation parameters showed a significantly difference between the young group and both the adult and old groups (p 2 ) for 85 Sr in the slow compartment decreased in regular order from the young to the old groups. In the bone 85 Sr-retention equations Tb 2 of the slow compartment for 85 Sr in the young group was significantly lower than the adult and old groups. The doses of the whole body and red-marrow for young rats were 4.2 times as much as those of adult rats, and 6.2 and 5.9 times as much as those old rats. The dose-cumulative speeds was most quick in the young groups and similar in the adult and the old

Nd:YAG laser associated with metal salts solutions in the treatment of dentinal hypersensitivity

International Nuclear Information System (INIS)

Glauche, Carlos Eugenio Correia

2001-01-01

The objective of this study was to observe the ultrastructural changes caused by the radiation of Nd:YAG laser on the tooth tissue and determine qualitatively the presence of Sn ++ , Sr ++ and F - , inside the dentin, being it irradiated or not. Ten molar teeth recently extracted were cut into 2 mm discs. The samples were soaked in a EDTA solution at 17% for 2 minutes and divided into five groups. Group I: the samples were irradiated with Nd:YAG laser (1,5 W, 100 mJ, 15 Hz, 150 μs and 125 J/cm 2 ) and after that, a treatment with an SnF 2 aqueous solution at 10% for 30 minutes. Group II: the samples got laser irradiation with the same parameters and then a treatment with an SrCl 2 solution at 10% as a toothpaste (Sensodyne TM ) for 30 minutes. Group III: the samples just got a treatment with a SnF 2 aqueous solution at 10% for 30 minutes. Group IV: the samples just got a treatment with a SrCl 2 toothpaste (Sensodyne TM ) for 30 minutes. Group V: samples that just got laser irradiation in the parameters above mentioned. Then, all samples were prepared for scanning electronic microscopy (SEM) and the samples of groups I, II, III and IV for energy dispersive X-ray microanalysis (EDX). The ultrastructure aspect of the dentin showed the surface totally altered by the irradiation. Pits and whitish globules were found amidst an heterogenous and rough structure, due to the melting and resolidification of the dental structure. Craters were also observed. Carbonization areas were absent. Ions Sn ++ were found at a depth of 250 μm in the samples of group I (Nd:YAG + SnF 2 ), whereas in the samples of group III, Sn ++ were not found deeper than 100 μm. Sr ++ could be detected at least at 500 μm in the inner dentin in the samples of group II (Nd:YAG + SrCl 2 ). However, Sn ++ were not found at 50 μm in group IV samples. Ions F - were just found in the irradiated samples of group I. According to the study results we observed that through ultrastructural changes, caused by

Field demonstration of in situ treatment of buried low-level radioactive solid waste with caustic soda and soda ash to immobilize 90Sr

International Nuclear Information System (INIS)

Spalding, B.P.

1984-02-01

A low-level radioactive solid waste disposal trench was injected on four occasions with solutions of caustic soda, soda ash, caustic soda, and lime/soda ash, respectively. Because investigations had indicated that 90 Sr could be coprecipitated with soil calcium carbonate by treatment with soda ash, this demonstration was undertaken as a test of its technical feasibility. After concentrations of 90 Sr and water hardness decreased within the intratrench monitoring wells; one well at the foot of the trench decreased from over 100 to a persistent level of less than 10 kBq of 90 Sr per liter. Recharge of 90 Sr from the trench to a sump immediately below was reduced by about 90%. Water hardness and 90 Sr concentrations were strongly correlated through time within each monitoring well, indicating that 90 Sr behaved as a tracer for soil calcium and magnesium. The disappearance of 90 Sr from the trench water, therefore, was an in situ water softening. Soil samples retrieved from the trench indicated that as much as 98% of the total 90 Sr was present as a coprecipitate with calcium carbonate. The hydrologic characterization of this trench indicated an average void space of 41% and an average trench-wall hydraulic conductivity of 3.4 x 10 -7 m/s. Sampling of the trench's discharge contamination plume indicated that it had resulted from a combination of subsurface seepage and bathtub overflow during infrequent periods of intense precipitation. A generic assessment of soda ash treatment indicated that treatment would be most effective for soils of high cation exchange capacity with either low ( 80%) basic cation saturation of that cation exchange capacity

TREATMENT OPTIMIZATION IN PATIENTS WITH STABLE ANGINA PECTORIS: FOCUS ON VERAPAMIL SR

Directory of Open Access Journals (Sweden)

I. M. Sokolov

2011-01-01

Full Text Available Possibilities of angina pectoris pharmacotherapy are analyzed. Achievement of target heart rate (HR 55-60 beats per minute in these patients is possible due to three classes of antianginal medications that slow down HR: beta blockers (BB, If-channel inhibitors, nondihydropyridine calcium channel blockers (CCB. Nondihydropyridine CCB verapamil in slow release (SR formulation is focused. The main results of randomized clinical trials (APSIS, VHAS, CRIS, EVERESTH, VAMPHYRE, INVEST, VESPA, DAVIT-1, DAVIT-2, which have proven efficacy and safety, are presented. Verapamil SR is indicated for the treatment of angina pectoris in patients without history of myocardial infarction (MI; angina patients experienced MI without systolic heart failure and with contraindications to BB; angina with arterial hypertension; left ventricular diastolic dysfunction; peripheral arteries obliterating atherosclerosis; silent myocardial ischemia; vasospastic angina; angina associated with supraventricular cardiac arrhythmias (especially in permanent atrial fibrillation except Wolff-Parkinson-White and Lown-Ganong-Levine syndromes; after coronary angioplasty and the placement of bare metal stents.

Synthesis and characterization of tin(IV) antimonate and study of its ion-exchange equilibria

International Nuclear Information System (INIS)

Burham, N.; Abdel-Halim, S.H.; El-Shahat, M.F.

1995-01-01

Tin(IV) antimonate with different Sb/Sn molar ratios has been prepared. The characterization of the product materials was carried out using X-ray diffraction pattern, thermal analysis and infrared spectra. The saturation capacities of sodium and cesium were found to increase with Sb/Sn molar ratios. The K d values on thermal treatment of tin(IV) antimonate, as a cation exchanger, have been measured for some heavy metal ions in the temperature range of 50-400 deg C. The maximum adsorption of 10 -4 M of the metal ions studied was obtained at 400 deg C. The selectivity sequence was Eu 3+ > Co 2+ > Sr 2+ > Cs + for the sample heated up to 400 deg C. No adsorption was observed on the sample heated at 700 deg C because of the formation of SnO 2 and Sb 6 O 13 . (author) 9 refs.; 7 figs.; 5 tabs

Source Signature of Sr Isotopes in Fluids Emitting From Mud volcanoes in Taiwan

Science.gov (United States)

Chung, C.; You, C.; Chao, H.

2003-12-01

Located at the boundary between the Philippine Sea Plate and the Asia Continental Plate, abundance of mud volcanoes were erupted on land in Taiwan. According to their occurrences and associated tectonic settings, these mud volcanoes were classified into four groupies. The group (I) mud volcanoes are located in the western coastal plane, whereas group (II) and (III) are situated near the Kutinkung anticline axis and the Chishan fault respectively. The group (IV) mud volcanoes are discovered at the Coastal Range. Although there are numerous studies focused on morphology, possible fluid migration paths and sources are poorly understood. We have collected and analyzed major ions and Sr isotopic ratios in fluids separated from various mud volcanoes in Taiwan. Chemical contents of these fluids were measured by IC and the emitted gasses were analyzed by GC. The Sr concentrations in these fluids were determined using AA and the isotopic compositions were analyzed by TIMS. The dominated ions in fluids are Na and Cl which account for 98% of dissolved materials. All fluids show similar Na/Cl ratios(0.7-0.8), slightly higher than seawater but each group has unique Sr isotopic signature. Waters expelled from group I mud volcanoes featured with low salinity and high Sr isotopic ratios ranged from 0.71150 to 0.71175. Groups II and III were outcroped in the Kutinkung formation but show distinctive chemical compositions. Group II fluids have four times Cl concentrations(358-522mM) compared with those of group III(85-162mM). The latter fluids appear to be more radiogenic(0.71012- 0.71075) indicating possible influence due to water-rock interactions. Low 87Sr/86Sr(0.70692-0.70939) is typical characteristic of mud volcano fluids in group IV where large Mg and K depletion were discovered, suggesting effects due to sediment diagenetic processes. The chemical compositions of mud volcano associated gasses show similar distribution pattern. The major gas constituents in mud volcano zones

Effect of different treatments on {sup 85}Sr plant uptake in various soil types

Energy Technology Data Exchange (ETDEWEB)

Koblinger-Bokori, E.; Szerbin, P. [' Frederic Joliot-Curie' National Research Institute for Radiobiology and Radiohygiene, Budapest (Hungary)

2000-05-01

In the recent years radioecological studies are concentrated on the investigation of restoration possibilities of contaminated ecosystems. These studies are aimed to develop methods for decreasing the bioavailability of the radionuclides released to the environment. Radionuclides of long half-lives, such as {sup 90}Sr and {sup 137}Cs, are of special importance from the point of human health, since these nuclides can enter the human body via the food-chain and increase the radiation burden for many years. {sup 90}Sr and {sup 137}Cs contamination of the environment may occur as a result of atmospheric releases during nuclear accidents. For instance, considerable amounts were released to the atmosphere during the Chernobyl reactor accident. In the presented study strontium plant uptake from different types of soil was investigated. To avoid the difficulties related to {sup 90}Sr determination, the gamma-emitting strontium isotope {sup 85}Sr is used at the experiments (no isotopic effect takes place). The plant selected is yellow leguminous bean. Most typical Hungarian soils (leached Ramann brown forest soil, alluvial soil, chernozem-light sandy soil and calcareous chernozem soil) were selected for the experiments carried out under laboratory conditions. Results are presented in relation to major soil characteristics. Effects of two different treatments: lime and organic matter fertilizations on plant uptake are given. The highest uptake was found in bean grown on leached Ramann brown forest soil, whereas the lowest value was measured in the plant grown in calcareous chernozem soil. Organic fertilization significantly reduced the uptake of radiostrontium in all investigated types of soil. The largest factor of reduction was found to be as high as 3.5. Lime fertilization was less effective. Our study clearly demonstrates that carefully selected post-accident treatments (e.g. organic fertilization following strontium contamination) can significantly reduce the

The dynamics of accumulation and disappearance of {sup 89}Sr in tea

Energy Technology Data Exchange (ETDEWEB)

Chuanqun, Chen; Shouxiang, Wang; Yongxi, Zhang; Zhiming, Sun [Zhejiang Agricultural Univ., Hangzhou (China). Inst. of Nuclear Agricultural Sciences

1994-06-01

The {sup 89}Sr was put into a tea tree-soil system by different ways. The results showed that for {sup 89}Sr put into the system through the above-ground 1 part of tea tree, its concentration in tea was much higher than that through soil. The concentration of {sup 89}Sr in older tea was higher than that in shoot for the same treatment. The accumulation and disappearance of {sup 89}Sr in tea varied with the treatments. For the treatment through the above-ground part, the concentrations of {sup 89}Sr in older tea and shoot were monotonously decreasing with time. For the treatment through soil the concentration of {sup 89}Sr in shoot increased initially to a maximum value, then decreased slowly; while the concentration of {sup 89}Sr in older tea increased quickly in a definite period, then increased slowly to gain a saturated value. In addition, the values of concentration factor of {sup 89}Sr in the older tea and shoot were determined, too.

Photoinduced structural transformation of SrFeO3 and Ca2Fe2O5 during photodegradation of methyl orange

International Nuclear Information System (INIS)

Yang Yang; Cao Zhengquan; Jiang Yinshan; Liu Lihua; Sun Yanbin

2006-01-01

Photodegradation of methyl orange solution under UV light irradiation have been studied over photocatalyst perovskite SrFeO 3 and brownmillerite Ca 2 Fe 2 O 5 . XRD and FTIR analysis show that both SrFeO 3 and Ca 2 Fe 2 O 5 transform to carbonates during the photodegradation process of methyl orange. This result indicates that UV light irradiation induce a photochemical reaction between photocatalysts and CO 2 released from the photodegradation of methyl orange. The photochemical reaction between photocatalysts and CO 2 is responsible for the transformation of the structures. The fact that SrFeO 3 has better photocatalytic property and endures serious transformation than Ca 2 Fe 2 O 5 is due to existence of unstable Fe (IV) in the perovskite structure of SrFeO 3. Such kind of Fe (IV) makes perovskite structure unstable and sensitive to ambient (especially sensitive to UV light irradiation)

CHARACTERIZATION OF THE PARTIALLY PURIFIED PLANTARCIN SR18 PRODUCED BY LACTOBACILLUS PLANTARUM SR18

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Wagih El-Shouny

2013-04-01

Full Text Available The bacteriocin bound to the cells and that secreted into the culture filtrate of Lactobacillus plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. Bacteriocins were purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and culture filtrate proteins (plantarcin SR18 b, respectively. The SDS-PAGE of partially purified Plantarcin SR18a showed a molecular weight of 3.5 KDa. While, plantarcin SR18 b had a molecular weight of 10.3 KDa. The antibacterial activity of the tested plantarcin SR18 preparations suffered no measurable loss after 45 min at 80ºC. Whereas, At 100ºC, significant decrease in the activity of bacteriocin preparations (60- 80 % took place by the end of 45 min. At pH ranged from 5-8, the activity of the plantarcin SR18 preparations suffered no measurable loss. Dissociating agents significantly affected the bacteriocin activity. Thus, tween 80 and mercaptoethanol increased the activity of bacteriocin preparations to 1.2-1.4 fold. Sodium dodecyl sulphate (SDS increased the activity of the tested bacteriocin preparations by about 20%.The lowest residual activity (60% was recorded after treatment with Triton X100 for 45 min. Protease completely inhibited the activities of all forms of plantarcin SR18 after 45 min at 37ºC.

Advanced-stage III/IV follicular lymphoma. Treatment strategies for individual patients

Energy Technology Data Exchange (ETDEWEB)

Heinzelmann, Frank; Bamberg, Michael; Weinmann, Martin [Dept. of Radiation Oncology, Univ. of Tuebingen (Germany); Ottinger, Hellmut [Dept. of Bone Marrow Transplantation, Univ. of Essen (Germany); Engelhard, Marianne [Dept. of Radiation Oncology, Univ. of Essen (Germany); Soekler, Martin [Dept. of Internal Medicine II, Univ. of Tuebingen (Germany)

2010-05-15

Background: in patients with advanced-stage III/IV follicular lymphoma (FL), there are many treatment options available. The current challenge is to choose the optimal strategy for the individual patient. Methods: the literature was reviewed with respect to treatment strategies in patients with advanced FL by screening the PubMed databank. Results: in advanced-stage III/IV FL, median survival may approach 8-10 years. Treatment strategies include a watch-and-wait strategy, chemoimmunotherapy, monotherapy with rituximab, and - as an experimental approach so far - radioimmunotherapy. The use of autologous hematopoietic stem cell transplantation (HSCT) for patients in first remission or chemosensitive relapse prolongs progression-free survival while the effect on overall survival remains unclear compared to standard chemotherapy. However, long-term results are flawed by high relapse rates and risk of secondary malignancies. In patients with relapsed/chemoresistant disease, allogeneic HSCT constitutes the only curative approach but is associated with high treatment-related mortality. In the palliative setting, low-dose involved-field irradiation constitutes an effective treatment option in order to control local symptoms with potential long-lasting response. Conclusion: in case of advanced-disease FL, asymptomatic patients can be managed expectantly. In symptomatic patients, chemoimmunotherapy is regarded as standard therapy. In symptomatic elderly patients with relevant comorbidities, rituximab {+-} single-agent chemotherapy, or low-dose involved-field radiotherapy might be appropriate. For younger patients with chemoresistant/relapsed disease, allogeneic HSCT might be considered, since advances in supportive care and better patient selection have resulted in improved outcomes. (orig.)

Reactive transport of Sr, Cs and Tc through a column packed with fracture-filling material

International Nuclear Information System (INIS)

Cui, D.; Eriksen, T.

1998-01-01

The migration behaviour of the fission products 90 Sr, 137 Cs and 99 Tc in a granite fracture-groundwater system was studied in column experiments using crushed Stripa granite fracture-filling material (125-250 μm) as a sorbent. Based on breakthrough curves of Sr 2+ , Cs + , TcO 4 - and anthraquinonsulphonate, the distribution ratio K d (cm 3 /g) values for Sr 2+ and Cs + were estimated to be 1.5 and 2 respectively; non-sorbing behaviour of TcO 4 - under oxic conditions was observed. The diffusion of Sr 2+ in the material is shown to be a kinetic-controlling step in the desorption process that followed the initial leaching. Under reducing conditions, it was found that TcO 4 - was reduced to TcO 2 .nH 2 O(s) by the Fe(II)-containing fracture-filling material and Tc(IV) aq was rapidly sorbed by the material. This observation proves that the migration of technetium under reducing conditions in deep groundwater systems will not only be controlled by the solubility of TcO 2 . nH 2 O(s) and the speed of groundwater flow but also by the rapid sorption of Tc(IV) aq on all available mineral surfaces. (orig.)

Population ecology and conservation status of the last natural population of English yew Taxus baccata in Denmark

DEFF Research Database (Denmark)

Svenning, Jens-Christian; Magård, Else

1999-01-01

English yew Taxus baccata L. has become extinct or rare in many parts of Europe. Here we investigate the status of the only natural population persisting in Denmark. While many other yew populations are declining, the Danish population increased from 2000 in 1998....... This was most likely due to the thinning of the tree stand at this site, as reproductive activity, strobilus production, and recruitment were enhanced at better lit microsites. The declining status of other populations is probably often caused by succession from open woodland to dense forest. The light...... dependency is consistent with the Quaternary history of yew. The sex ratio of the Danish yew population was female-biased, probably due to chance. Yew invaded forest areas neighbouring source populations at rates of 3 m yr−1, but forest management impeded this process....

A novel technique for the treatment of stages III to IV hemorrhoids

Science.gov (United States)

Lin, Guoqiang; Ge, Qiongxiang; He, Xiaokang; Qi, Haixin; Xu, Li

2017-01-01

Abstract To compare the efficacy of homemade anal cushion suspension clamp combined with harmonic scalpel (ACS) and Milligan–Morgan hemorrhoidectomy combined with electric knife (MMH) in the treatment of stages III to IV hemorrhoids. We conducted a retrospective study of 99 patients with stages III to IV hemorrhoids hospitalized from January to December in 2013. Among them, 51 patients were treated with ACS, while 48 patients received MMH. Data from clinical recording and follow-up included operative time, intraoperative blood loss, hospitalization information, postoperative pain, and postoperative complications. Operative time, intraoperative blood loss and hospitalization time in ACS group were significantly less than those in MMH group (P hemorrhoids. PMID:28658138

The possible physical mechanism for the EAP–SR co-action

KAUST Repository

Gong, Zhiqiang

2017-11-17

The anomalous characteristics of summer precipitation and atmospheric circulation in the East Asia–West Pacific Region (EA–WP) associated with the co-action of East Asia/Pacific teleconnection–Silk Road teleconnection (EAP–SR) are investigated in this study. The compositions of EAP–SR phase anomalies can be expressed as pattern I (+ +), pattern II (+ −), pattern III (− −), and pattern IV (− +) using EAP and SR indices. It is found that the spatial distribution of summer precipitation anomalies in EA–WP corresponding to pattern I (III) shows a tripole structure in the meridional direction and a zonal dipole structure in the subtropical region, while pattern II (IV) presents a tripole pattern in meridional direction with compressed and continuous anomalies in the zonal direction over the subtropical region. The similar meridional and zonal structures are also found in the geopotential height anomalies at 500-hPa, as well as wind anomalies and moisture convergence at 850-hPa. Finally, a schematic mechanism for the EAP–SR co-action upon the summer precipitation in EA–WP is built: (1) Pattern I (III) exhibits that the negative (positive) sea surface temperature (SST) anomalies over tropical East Pacific may cause the enhanced (weakened) convective activity dominating the West Pacific, trigger the positive (negative) EAP teleconnection and produce more (less) precipitation. Besides, the negative (positive) SST anomalies over the Indonesia Maritime Continent (IMC) may further weaken (strengthen) anomalous downward (upward) motion over the South China Sea (SCS), cause negative (positive) geopotential height anomalies at the middle troposphere and surrounding regions through the function of the tropical Hadley circulation. Then the negative (positive) geopotential height anomalies could motivate the positive (negative) EAP teleconnection through the northward propagation of wave-activity perturbation. Meanwhile, a positive (negative) geopotential

The possible physical mechanism for the EAP-SR co-action

Science.gov (United States)

Gong, Zhiqiang; Feng, Guolin; Dogar, Muhammad Mubashar; Huang, Gang

2017-11-01

The anomalous characteristics of summer precipitation and atmospheric circulation in the East Asia-West Pacific Region (EA-WP) associated with the co-action of East Asia/Pacific teleconnection-Silk Road teleconnection (EAP-SR) are investigated in this study. The compositions of EAP-SR phase anomalies can be expressed as pattern I (+ +), pattern II (+ -), pattern III (- -), and pattern IV (- +) using EAP and SR indices. It is found that the spatial distribution of summer precipitation anomalies in EA-WP corresponding to pattern I (III) shows a tripole structure in the meridional direction and a zonal dipole structure in the subtropical region, while pattern II (IV) presents a tripole pattern in meridional direction with compressed and continuous anomalies in the zonal direction over the subtropical region. The similar meridional and zonal structures are also found in the geopotential height anomalies at 500-hPa, as well as wind anomalies and moisture convergence at 850-hPa. Finally, a schematic mechanism for the EAP-SR co-action upon the summer precipitation in EA-WP is built: (1) Pattern I (III) exhibits that the negative (positive) sea surface temperature (SST) anomalies over tropical East Pacific may cause the enhanced (weakened) convective activity dominating the West Pacific, trigger the positive (negative) EAP teleconnection and produce more (less) precipitation. Besides, the negative (positive) SST anomalies over the Indonesia Maritime Continent (IMC) may further weaken (strengthen) anomalous downward (upward) motion over the South China Sea (SCS), cause negative (positive) geopotential height anomalies at the middle troposphere and surrounding regions through the function of the tropical Hadley circulation. Then the negative (positive) geopotential height anomalies could motivate the positive (negative) EAP teleconnection through the northward propagation of wave-activity perturbation. Meanwhile, a positive (negative) geopotential height anomalous pattern

Dosimetric comparison of electron beam and 90Sr+90Y applicator for keloids treatment

International Nuclear Information System (INIS)

Coelho, Talita S.; Tada, Ariane; Antonio, Patricia L.; Yoriyaz, Helio; Fernandes, Marco A.R.

2009-01-01

Studies have been shown that among several methods that have been used for the treatment of keloids the surgical excision followed by the adjuvant radiotherapy presents the lowest relapsed rate of the injury. In this work a comparative dosimetric study has been performed using a 4 MeV electron beam from a Varian Clinac 2100C linear accelerator at the radiotherapy service of the Hospital das Clinicas of UNESP-HC, Botucatu-SP and an Amershan 90 Sr+ 90 Y brachytherapy applicator with 1491 MBq of activity. Percentage depth dose curves from ionization chamber measurements and through Monte Carlo simulation have been obtained and compared. Dose measurements have been obtained using parallel plates ionization chamber (Esradin A12) and extrapolation mini-chamber developed at IPEN. The dose calculations have been obtained using the well-known Monte Carlo radiation transport code MCNP-4C. Maximum dose differences obtained between measured/calculated values for 90 Sr+ 90 Y applicator and for the electron beam were, respectively: 7.8 % and 8.0%. The profiles of the depth and superficial tissue dose distribution produced by the electron beam revealed themselves flatter and more homogeneous than those produced by the 90 Sr+ 90 Y applicator, especially to wider fields, which cannot be obtained with beta therapy applicators because of their geometric limitations. In conclusion this present work has shown that 90 Sr+ 90 Y applicators could be efficient for small and very superficial lesions but in most cases electron beam sources are more adequate especially for large and deeper lesions. (author)

Electrical transport across nanometric SrTiO3 and BaTiO3 barriers in conducting/insulator/conducting junctions

Science.gov (United States)

Navarro, H.; Sirena, M.; González Sutter, J.; Troiani, H. E.; del Corro, P. G.; Granell, P.; Golmar, F.; Haberkorn, N.

2018-01-01

We report the electrical transport properties of conducting/insulator/conducting heterostructures by studying current-voltage IV curves at room temperature. The measurements were obtained on tunnel junctions with different areas (900, 400 and 100 μm2) using a conducting atomic force microscope. Trilayers with GdBa2Cu3O7 (GBCO) as the bottom electrode, SrTiO3 or BaTiO3 (thicknesses between 1.6 and 4 nm) as the insulator barrier, and GBCO or Nb as the top electrode were grown by DC sputtering on (100) SrTiO3 substrates For SrTiO3 and BaTiO3 barriers, asymmetric IV curves at positive and negative polarization can be obtained using electrodes with different work function. In addition, hysteretic IV curves are obtained for BaTiO3 barriers, which can be ascribed to a combined effect of the FE reversal switching polarization and an oxygen vacancy migration. For GBCO/BaTiO3/GBCO heterostructures, the IV curves correspond to that expected for asymmetric interfaces, which indicates that the disorder affects differently the properties at the bottom and top interfaces. Our results show the role of the interface disorder on the electrical transport of conducting/insulator/conduction heterostructures, which is relevant for different applications, going from resistive switching memories (at room temperature) to Josephson junctions (at low temperatures).

Modification of SrTiO3 single-crystalline surface after plasma flow treatment

Energy Technology Data Exchange (ETDEWEB)

Levin, Alexandr A.; Weissbach, Torsten; Leisegang, Tilmann; Meyer, Dirk C. [Institut fuer Strukturphysik, Technische Universitaet Dresden, 01062 Dresden (Germany); Kulagin, Nikolay A. [Kharkiv National University for Radioelectronics, av. Shakespeare 6-48, 61045 Kharkiv (Ukraine); Langer, Enrico [Institut fuer Festkoerperphysik, Technische Universitaet Dresden, 01062 Dresden (Germany)

2009-07-01

Surface of pure and transition metal-doped SrTiO3(STO) single crystals before and after hydrogen plasma-flow treatment (energy of 5..20 J/cm2) is investigated by wide-angle X-ray diffraction (WAXRD), fluorescence X-ray absorption near edge structure (XANES) and scanning electron microscopy (SEM) techniques. Plasma treatment results in the formation of a textured polycrystalline layer at the surface of the single-crystalline samples with different orientation. The formation of the quasi-ordered structures consisting of nanoscale-sized pyramids is observed by SEM. XANES evidences the change of the valency of the part of Ti4+ to Ti3+ due to the plasma treatment. The data obtained together with results of X-ray spectroscopy measurements gives evidences of the change of stoichiometry of the STO samples resulting in a change of their physical properties after plasma treatment.

Incorporation of sulfate or selenate groups into oxotellurates(IV). I. Calcium, cadmium, and strontium compounds

International Nuclear Information System (INIS)

Weil, Matthias; Shirkhanlou, Mahdi

2017-01-01

Seven new mixed oxochalcogenate compounds in the systems M II /X VI /Te IV /O/(H), (M II = Ca, Cd, Sr; X VI = S, Se) were obtained under hydrothermal conditions (210 C, one week). Crystal structure determinations based on single-crystal X-ray diffraction data revealed the compositions Ca 3 (SeO 4 )(TeO 3 ) 2 , Ca 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (H 2 O)(SO 4 )(Te 3 O 8 ), Cd 4 (SO 4 )(TeO 3 ) 3 , Cd 5 (SO 4 ) 2 (TeO 3 ) 2 (OH) 2 , and Sr 3 (H 2 O) 2 (SeO 4 )(TeO 3 ) 2 for these phases. Peculiar features of the crystal structures of Ca 3 (SeO 4 )(TeO 3 ) 2 , Ca 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (H 2 O)(SO 4 )(Te 3 O 8 ), and Sr 3 (H 2 O) 2 (SeO 4 )(TeO 3 ) 2 are metal-oxotellurate(IV) layers connected by bridging XO 4 tetrahedra and/or by hydrogen-bonding interactions involving hydroxyl or water groups, whereas Cd 4 (SO 4 )(TeO 3 ) 3 and Cd 5 (SO 4 ) 2 (TeO 3 ) 2 (OH) 2 crystallize as framework structures. Common to all crystal structures is the stereoactivity of the Te IV electron lone pair for each oxotellurate(IV) unit, pointing either into the inter-layer space, or into channels and cavities in the crystal structures. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

gender-specific outcome after paclitaxel-eluting stent implantation in japanese patients with coronary artery disease--sub-analysis of the Japan TAXUS Express2 post-marketing survey.

Science.gov (United States)

Okura, Hiroyuki; Nakamura, Masato; Kotani, Jun-Ichi; Kozuma, Ken

2013-01-01

 Although previous randomized and non-randomized studies have demonstrated the safety and efficacy of paclitaxel-eluting stents (PES), a higher revascularization rate has been reported in women than in men. A sub-analysis of the TAXUS Japan Post-market Surveillance Study (TAXUS-PMS) was done to assess the influence of gender on clinical outcome.  A total of 2,132 PES-treated Japanese patients (women, n=551) from this registry were analyzed. Subjects were stratified by gender to compare 1-year clinical outcome. PES-treated women were older and more likely to have insulin-treated diabetes and hypertension. In contrast, PES-treated men were more likely to be smokers, have a previous history of myocardial infarction, and lower ejection fraction. While cardiac death, myocardial infarction and stent thrombosis were similar between men and women, major cardiac events tended to be lower in women than in men (6.4% vs. 8.8%, P=0.08). Although women had significantly smaller reference vessel size (2.46±0.53 mm vs. 2.59±0.60 mm, Ptarget lesion revascularization rate was significantly lower in women than in men (4.2% vs. 6.5%, P<0.05).  Despite a higher risk profile, Japanese women treated with PES did not have a higher rate of repeat revascularization or major adverse clinical outcome than PES-treated men at 1 year. 

Epitaxial growth of YBa2Cu307−δ films on SrTiO3 (100) by direct solution precursor deposition

International Nuclear Information System (INIS)

Bustamante, A; Garcia, Jorge; Osorio, Ana M; Valladares, Luis De Los Santos; Barnes, C H W; González, J C; Azuma, Y; Majima, Y; Aguiar, J Albino

2014-01-01

We study the optimal temperature to obtain YBa 2 Cu 3 O 7-δ epitaxial films grown onto SrTiO 3 substrates by direct solution deposition. The samples received heat treatment at 820, 840 and 860 °C, then characterized by XRD, observing the (00l) profiles; and magnetic susceptibility measurements. The T C-onset for all the samples was 90 K. In addition, the current – voltage (I-V) measurements shows typical tunneling signals corresponding to normal metal-superconducting junctions indicating the films are promising for potential electrical applications.

Theoretical prediction and experimental confirmation of unusual ternary ordered semiconductor compounds in Sr-Pb-S system.

Science.gov (United States)

Hao, Shiqiang; Zhao, Li-Dong; Chen, Chang-Qiang; Dravid, Vinayak P; Kanatzidis, Mercouri G; Wolverton, Christopher M

2014-01-29

We examine the thermodynamics of phase separation and ordering in the ternary Ca(x)Pb(1-x)S and Sr(x)Pb(1-x)S systems by density-functional theory combined with a cluster expansion and Monte Carlo simulations. Similar to most other ternary III-V or IV-VI semiconductor alloys, we find that bulk phase separation is thermodynamically preferred for PbS-CaS. However, we predict the surprising existence of stable, ordered ternary compounds in the PbS-SrS system. These phases are previously unreported ordered rocksalt-based compounds: SrPb3S4, SrPbS2, and Sr3PbS4. The stability of these predicted ordered phases is confirmed by transmission electron microscopy observations and band gap measurements. We believe this work paves the way for a combined theory-experiment approach to decipher complex phase relations in multicomponent chalcogenide systems.

A retrospective chart review to assess the safety of nonablative fractional laser resurfacing in Fitzpatrick skin types IV to VI.

Science.gov (United States)

Clark, Charlotte M; Silverberg, Jonathan I; Alexis, Andrew F

2013-04-01

Laser resurfacing in patients with Fitzpatrick skin phototypes (SPT) IV to VI is associated with a higher risk of pigmentary alteration. There is a paucity of studies evaluating optimum treatment parameters for fractional lasers in darkly pigmented skin types. This is a retrospective review of medical records for patients with SPT IV to VI who were treated with a 1,550 nm erbium-doped fractional nonablative laser (Fraxel Re:Store SR 1550; Solta Medical, Hayword, CA). Data were collected from patient charts and the clinic laser logbook from January 2008 to January 2012. The frequency of treatment-associated postinflammatory hyperpigmentation (PIH) and treatment settings used were evaluated. A total of 115 total laser sessions (45 patients) were included in our analysis. Five of the sessions (4%) were accompanied by PIH, 2 of which occurred in a single patient. Only 1 episode of PIH lasted longer than 1 month (2 months). Two of the 5 cases had only transient PIH (≤7 days), one of which was reported by the patient and not clinically evident on examination. The 1,550 nm erbium-doped fractional laser is well tolerated in SPT IV to VI. Fractional laser resurfacing, with the settings used and pretreatment and posttreatment hydroquinone 4% cream, was associated with a low risk of PIH in darker skin types.

A New Class of Octahedral Molecular Sieve Materials for the Selective Removal and Sequestration of 90Sr2+

International Nuclear Information System (INIS)

Nyman, May D.; Nenoff, Tina M.; Tripathi, Akhilesh; Parise, John B.; Maxwell, Robert S.; Harrison, William T.A.

2000-01-01

The structure of Na 16 Nb 12.8 Ti 3.2 O 44.8 (OH) 3.2 · 8H 2 O, a member of a new family of Sandia Octahedral Molecular Sieves (SOMS) having a Nb/Na/M IV (M= Ti, Zr) oxide framework and exchangeable Na and water in open channels, was determined from Synchrotron X-ray data. The SOMS phases are isostructural with variable M IV :Nb(1:50--1:4) ratios. The SOMS are extremely selective for sorption of divalent cations, particularly Sr 2+ . The ion-exchanged SOMS undergo direct thermal conversion to a perovskite-type phase, indicating this is a promising new method for removal and sequestration of radioactive Sr-90 from mixed nuclear wastes

Recovery of Some Radioactive Nuclides from Radioactive Waste Solution Using Silicon(IV) Antimonate as a Cation Exchanger

International Nuclear Information System (INIS)

Aly, H.F.; Zakaria, E.S.; El-Shorbagy, M.M.; El-Naggar, I.M.

1999-01-01

A new inorganic ion exchanger, silicon(IV) antimonate was prepared by dropwise addition of antimony pentachloride and sodium silicate and shows excellent thermal and chemical stability. Ion exchange selectivities of cations Na +, Cs +, Sr 2+ and Co 2+ in nitric acid media have been exchanged with protons of silicon antimonate using batch technique, from these results, distribution coefficient, selectivity was found in the order Co 2+ > Sr 2+ > Na +> Cs +. The effective separation of Cs +, Na +, Sr 2+ and Co 2+ have been achieved with column technique from nitric acid media. The values of diffusion coefficient, energy and entropy of activation of Cs +, Na +, Sr 2+ and Co 2+ on silicon antimonate matrix were determined as a particle diffusion mechanism only and the values of diffusion inside the exchanger take the order Na +> Cs +> Co 2+ > Sr 2+

Treatment of type 2 diabetes mellitus with agonists of the GLP-1 receptor or DPP-IV inhibitors

DEFF Research Database (Denmark)

Holst, Jens Juul

2004-01-01

in the treatment of Type 2 diabetes, causing marked improvements in glycaemic profile, insulin sensitivity and beta-cell performance, as well as weight reduction. The hormone is metabolised rapidly by the enzyme dipeptidyl peptidase IV (DPP-IV) and, therefore, cannot be easily used clinically. Instead, resistant...... with exendin have been carried out for > 6 months and have indicated efficacy in patients inadequately treated with oral antidiabetic agents. Orally active DPP-IV inhibitors, suitable for once-daily administration, have demonstrated similar efficacy. Diabetes therapy, based on GLP-1 receptor activation...

Chloroplast microsatellite markers for Pseudotaxus chienii developed from the whole chloroplast genome of Taxus chinensis var. mairei (Taxaceae).

Science.gov (United States)

Deng, Qi; Zhang, Hanrui; He, Yipeng; Wang, Ting; Su, Yingjuan

2017-03-01

Pseudotaxus chienii (Taxaceae) is an old rare species endemic to China that has adapted well to ecological heterogeneity with high genetic diversity in its nuclear genome. However, the genetic variation in its chloroplast genome is unknown. Eighteen chloroplast microsatellite markers (cpSSRs) were developed from the whole chloroplast genome of Taxus chinensis var. mairei and successfully amplified in four P. chienii populations and one T. chinensis var. mairei population. Of these loci, 10 were polymorphic in P. chienii , whereas six were polymorphic in T. chinensis var. mairei . The unbiased haploid diversity per locus ranged from 0.000 to 0.641 and 0.000 to 0.545 for P. chienii and T. chinensis var. mairei , respectively. The 18 cpSSRs will be used to further investigate the chloroplast genetic structure and adaptive evolution in P. chienii populations.

Oxochloroalkoxide of the Cerium (IV and Titanium (IV as oxides precursor

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Machado Luiz Carlos

2002-01-01

Full Text Available The Cerium (IV and Titanium (IV oxides mixture (CeO2-3TiO2 was prepared by thermal treatment of the oxochloroisopropoxide of Cerium (IV and Titanium (IV. The chemical route utilizing the Cerium (III chloride alcoholic complex and Titanium (IV isopropoxide is presented. The compound Ce5Ti15Cl16O30 (iOPr4(OH-Et15 was characterized by elemental analysis, FTIR and TG/DTG. The X-ray diffraction patterns of the oxides resulting from the thermal decomposition of the precursor at 1000 degreesC for 36 h indicated the formation of cubic cerianite (a = 5.417Å and tetragonal rutile (a = 4.592Å and (c = 2.962 Å, with apparent crystallite sizes around 38 and 55nm, respectively.

Optimization of 90Sr/89Sr measurements

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Legarda F.

2012-04-01

Full Text Available One of the key points in the double measurement method for the measurement of both, 89Sr and 90Sr, by using a proportional counter is the choice of the times at which the measurements should be done. In this paper, the formulae to calculate the 89Sr and 90Sr detection limits in conditions of radioactive equilibrium between 90Y and 90Sr are derived, and an analysis of them as a function of the time between the two measurements is done. The choice for the time of the second measurement is going to depend on the desired quality of the results to be obtained.

Endovascular Treatment of a Carotid Dissecting Pseudoaneurysm in a Patient with Ehlers-Danlos Syndrome Type IV with Fatal Outcome

International Nuclear Information System (INIS)

Lim, Siok Ping; Duddy, Martin J.

2008-01-01

We present a patient with Ehlers-Danlos syndrome type IV (EDS IV) with a carotid dissecting pseudoaneurysm causing severe carotid stenosis. This lesion was treated endovascularly. Unfortunately, the patient died of remote vascular catastrophes (intracranial hemorrhage and abdominal aortic rupture). This unique case illustrates the perils of endovascular treatment of EDS IV patients and the need for preoperative screening for concomitant lesions. It also shows that a dissecting pseudoaneurysm can feasibly be treated with a covered stent and that closure is effective using Angioseal in patients with EDS IV

Strontium (Sr) separation from seawater using titanate adsorbents: Effects of seawater matrix ions on Sr sorption behavior

Science.gov (United States)

Ryu, Jungho; Hong, Hye-jin; Ryu, Taegong; Park, In-Su

2017-04-01

significantly hindered Sr sorption on TiNT, whereas Na had little effect on Sr sorption despite the sorption mechanism of Na-exchange. The effect of Ca on Sr sorption was evaluated in detail by introducing distribution coefficient (Kd) that is critical factor to determine the selectivity, revealing slightly higher selectivity for Sr. The adsorption-desoption test of Sr in real seawater medium enabled to determine Kd and concentration factor (CF) for co-existing matrix ions in seawater, and these values were assessed in both aspects of removal and recovery of Sr from seawater. The TiNT could be easily regenerated by acid treatment and reused for repeated cycle, supporting its long term use for the practical application of removing and recovering Sr from seawater.

Electronic properties and surface reactivity of SrO-terminated SrTiO3 and SrO-terminated iron-doped SrTiO3.

Science.gov (United States)

Staykov, Aleksandar; Tellez, Helena; Druce, John; Wu, Ji; Ishihara, Tatsumi; Kilner, John

2018-01-01

Surface reactivity and near-surface electronic properties of SrO-terminated SrTiO 3 and iron doped SrTiO 3 were studied with first principle methods. We have investigated the density of states (DOS) of bulk SrTiO 3 and compared it to DOS of iron-doped SrTiO 3 with different oxidation states of iron corresponding to varying oxygen vacancy content within the bulk material. The obtained bulk DOS was compared to near-surface DOS, i.e. surface states, for both SrO-terminated surface of SrTiO 3 and iron-doped SrTiO 3 . Electron density plots and electron density distribution through the entire slab models were investigated in order to understand the origin of surface electrons that can participate in oxygen reduction reaction. Furthermore, we have compared oxygen reduction reactions at elevated temperatures for SrO surfaces with and without oxygen vacancies. Our calculations demonstrate that the conduction band, which is formed mainly by the d-states of Ti, and Fe-induced states within the band gap of SrTiO 3 , are accessible only on TiO 2 terminated SrTiO 3 surface while the SrO-terminated surface introduces a tunneling barrier for the electrons populating the conductance band. First principle molecular dynamics demonstrated that at elevated temperatures the surface oxygen vacancies are essential for the oxygen reduction reaction.

Thermodynamic Modeling of Sr/TRU Removal

International Nuclear Information System (INIS)

Felmy, A.R.

2000-01-01

This report summarizes the development and application of a thermodynamic modeling capability designed to treat the Envelope C wastes containing organic complexants. A complete description of the model development is presented. In addition, the model was utilized to help gain insight into the chemical processes responsible for the observed levels of Sr, TRU, Fe, and Cr removal from the diluted feed from tank 241-AN-107 which had been treated with Sr and permanganate. Modeling results are presented for Sr, Nd(III)/Eu(III), Fe, Cr, Mn, and the major electrolyte components of the waste (i.e. NO 3 , NO 2 , F,...). On an overall basis the added Sr is predicted to precipitate as SrCO 3 (c) and the MnO 4 - reduced by the NO 2 - and precipitated as a Mn oxide. These effects result in only minor changes to the bulk electrolyte chemistry, specifically, decreases in NO 2 - and CO 3 2- , and increases in NO 3 - and OH - . All of these predictions are in agreement with the experimental observations. The modeling also indicates that the majority of the Sr, TRU's (or Nd(III)/Eu(III)) analogs, and Fe are tied up with the organic complexants. The Sr and permanganate additions are not predicted to effect these chelate complexes significantly owing to the precipitation of insoluble Mn oxides or SrCO 3 . These insoluble phases maintain low dissolved concentrations of Mn and Sr which do not affect any of the other components tied up with the complexants. It appears that the removal of the Fe and TRU'S during the treatment process is most likely as a result of adsorption or occlusion on/into the Mn oxides or SrCO 3 , not as direct displacement from the complexants into precipitates. Recommendations are made for further studies that are needed to help resolve these issues

Sr2CeO4: Electronic and structural properties

International Nuclear Information System (INIS)

Rocha, Leonardo A.; Schiavon, Marco A.; Nascimento, Clebio S.; Guimarães, Luciana; Góes, Márcio S.; Pires, Ana M.; Paiva-Santos, Carlos O.

2014-01-01

Highlights: • Sr 2 CeO 4 it was obtained from the heat treatment of Ce 3+ -doped strontium oxalate. • Rietveld analysis made it possible to obtain information about crystalline structure. • Experimental band gap value was compared with theoretical obtained by Sparkle/PM7. • The materials obtained shows intense photoluminescence and scintillator properties. - Abstract: This work presents on the preparation and photoluminescent properties of Sr 2 CeO 4 obtained from the heat treatment of Ce(III)-doped strontium oxalate (10, 25 and 33 mol%). The oxalate precursors were heat treated at 1100 °C for 12 h. The structure of this photoluminescent material was evaluated by the Rietveld method. The route used in this work to prepare the materials showed to be viable when compared to other synthesis reported in the literature. The Sr 2 CeO 4 material showed a broad and intense band emission with a maximum around 485 nm. The quantitative phase analysis showed that the Sr 2 CeO 4 photoluminescent phase is the majority one compared to the impurity phases of SrCeO 3 and SrCO 3 . From all results it was possible to verify a complete elimination of the CeO 2 phase for the sample obtained from the heat treatment of oxalate precursor containing 33 mol% of cerium(III). The material showed excellent properties for possible candidate as scintillator materials, and in the improvement of efficiency of solar cells when excited in the UV–vis region. The CIE chromaticity diagram it is also reported in this work

ACTH Regulation of Adrenal SR-B1

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Wen-Jun eShen

2016-05-01

Full Text Available The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters delivered via scavenger receptor, class B type 1 (SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. ACTH stimulates steroidogenesis through downstream actions on multiple components involved in steroidogenesis. Both acute and chronic ACTH treatment can modulate SR-B1 function including its transcription, its post transcriptional stability, its phosphorylation and dimerization status, as well as its interaction with other protein partners; all of which result in changes in the ability of SR-B1 to mediate HDL-cholesterol ester uptake and the supply of cholesterol for conversion to steroids. Here we provide a review of the recent findings on the regulation of adrenal SR-B1 function by ACTH.

Modulation of X ray DNA damage by SR-2508 +/- buthionine sulfoximine

International Nuclear Information System (INIS)

Kinsella, T.J.; Dobson, P.P.; Russo, A.; Mitchell, J.B.; Fornace, A.J. Jr.

1986-01-01

It has been demonstrated that glutathione (GSH) depletion with buthionine sulfoximine (BSO) potentiates SR-2508 radiosensitization in hypoxic cells. We have measured the effect of SR-2508 alone, BSO alone, and combined treatment on radiation-induced DNA strand breaks in hypoxic V79 cells using alkaline and neutral elution. DNA base damage recognized by a damage specific endonuclease from M. luteus was also studied. Hypoxic irradiation markedly reduces the efficiency of single-strand (SSB) and double-strand breaks (DSB) to 10-20% compared to oxic irradiation. Hypoxia had less effect on the efficiency of base damage (ESS). BSO treatment alone, resulting in GSH depletion to less than 5% of controls, had little effect of hypoxic-SSB, DSB, and ESS. SR-2508 (5 mM) treatment alone in hypoxic cells increased the number of SSB, DSB and ESS to approximately half of that resulting from oxic irradiation. However, the combination of BSO and SR-2508 in hypoxic cells resulted in SSB and DSB comparable to oxic irradiation. This combined treatment resulted in less effect on ESS. We conclude that the observed hypoxic radiosensitization, using clonogenic survival assays with combined BSO-SR-2508, correlates with our results assessing DNA strand breaks and base damage

High cost of stage IV pressure ulcers.

Science.gov (United States)

Brem, Harold; Maggi, Jason; Nierman, David; Rolnitzky, Linda; Bell, David; Rennert, Robert; Golinko, Michael; Yan, Alan; Lyder, Courtney; Vladeck, Bruce

2010-10-01

The aim of this study was to calculate and analyze the cost of treatment for stage IV pressure ulcers. A retrospective chart analysis of patients with stage IV pressure ulcers was conducted. Hospital records and treatment outcomes of these patients were followed up for a maximum of 29 months and analyzed. Costs directly related to the treatment of pressure ulcers and their associated complications were calculated. Nineteen patients with stage IV pressure ulcers (11 hospital-acquired and 8 community-acquired) were identified and their charts were reviewed. The average hospital treatment cost associated with stage IV pressure ulcers and related complications was $129,248 for hospital-acquired ulcers during 1 admission, and $124,327 for community-acquired ulcers over an average of 4 admissions. The costs incurred from stage IV pressure ulcers are much greater than previously estimated. Halting the progression of early stage pressure ulcers has the potential to eradicate enormous pain and suffering, save thousands of lives, and reduce health care expenditures by millions of dollars. Copyright © 2010 Elsevier Inc. All rights reserved.

Constraints on Ca/Sr as a Proxy for Calcium in Forest Ecosystems

Science.gov (United States)

Hoff, C. J.; Hobbie, E. A.; Hallett, R.; Colpaert, J.; Bryce, J. G.

2004-05-01

Calcium is a key plant nutrient and important base cation in ecosystems. Our current efforts to quantify Ca cycling in ecosystems rely on indirect proxies, e.g., Ca/Sr or Sr isotopic systems (1). An important assumption in these applications is that the elemental ratio of calcium to strontium faithfully represents calcium cycling and that little fractionation occurs through biogeochemical and physiological processes. However, several researchers have reported variations in Ca/Sr, e.g. among different tree tissues (2) and during weathering processes (3), raising doubts about the suitability of the proxy. To address the question of reliability, we measured Ca/Sr values in a culture study in which Scots pines were grown at low or high nutrient supply rates (3% per day or 5% per day). Because mycorrhizal fungi are intimately involved in plant nutrient supply, plants were also grown either uncolonized or colonized with one of two different species of mycorrhizal fungi (Suillus luteus and Thelephora terrestris). Our preliminary results indicate that Ca/Sr values differ between high and low nutrient treatments, root and foliage, and mycorrhizal treatments. In individual seedlings, roots have lower Ca/Sr than foliage by absolute factors of 2-5. The magnitude of the effect is apparently determined by a combination of environmental factors including both the nutrient and mycorrhizal treatments. These results indicate that Ca and Sr are partitioned differently between nutrient and mycorrhizal treatments and between plant fractions despite the common nutrient broth and substrate. Thus, Ca/Sr values alone are not reliable tracers of Ca within an ecosystem because of partitioning of Ca and Sr during nutrient transport within the plant-mycorrhizal system. We are presently refining analytical techniques and conducting leachate experiments to improve the quantification of this Ca/Sr fractionation. We are also exploring the use of isotopic tracers to study calcium biogeochemical

[Surgical treatment of the primary tumor in stage IV breast cancer].

Science.gov (United States)

Jiménez Anula, Juan; Sánchez Andújar, Belén; Machuca Chiriboga, Pablo; Navarro Cecilia, Joaquín; Dueñas Rodríguez, Basilio

2015-01-01

The aim of the study was to analyze the impact of loco-regional surgery on survival of patients with stage IV breast cancer. Retrospective study that included patients with breast cancer and synchronous metastases. Patients with ECOG above 2 and high-risk patients were excluded. The following variables were evaluated: age, tumor size, nodal involvement, histological type, histological grade, hormone receptor status, HER2 overexpression, number of affected organs, location of metastases and surgical treatment. The impact of surgery and several clinical and pathologic variables on survival was analyzed by Cox regression model. A total of 69 patients, of whom 36 (52.2%) underwent surgery (study group) were included. After a mean follow-up of 34 months, the median survival of the series was 55 months and no significant differences between the study group and the group of patients without surgery (P=0.187) were found. Two factors associated with worse survival were identified: the number of organs with metastases (HR=1.69, IC 95%: 1.05-2.71) and triple negative breast cancer (HR=3.49, IC 95%: 1.39-8.74). Loco-regional surgery, however, was not associated with survival. Loco-regional surgical treatment was not associated with improved survival inpacientes with stage IV breast cancer. The number of organs with metastases and tumors were triple negative prognostic factors for survival. Copyright © 2014 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Sr-90 determination in aqueous and soils samples

International Nuclear Information System (INIS)

Gonzalez Sintas, Maria F.; Cerchietti, Maria L.; Arguelles, Maria G.

2009-01-01

The main objective of this paper is to evaluate the method for Sr-90 determination in aqueous sample and soils. Area and Personal Dosimetry laboratory (DPA) determines the presence of Sr-90 by Liquid Scintillation (LSC) by applying method of the double window and corresponding adjustments. Calibration is performed by standard solutions of 90 Sr/ 90 Y, where spectral 90 Sr and 90 Y zones are optimized. The initial treatment of the liquid samples includes the concentration for evaporation, while the solid ones dissolve for microwave and acidic digestion. The separation of the analyte involves a selective chromatographic extraction. An average efficiency for 90 Sr of 77 ± 1 % was obtained; the factor a/b was 0,85 ± 0,01 and recovery of 82 ± 8 %. The resultant MAD was 0,10 Bq/L in aqueous samples and 0,10 Bq/g in solid samples. (author)

Thermal exposure effects on the in vitro degradation and mechanical properties of Mg-Sr and Mg-Ca-Sr biodegradable implant alloys and the role of the microstructure.

Science.gov (United States)

Bornapour, M; Celikin, M; Pekguleryuz, M

2015-01-01

Magnesium is an attractive biodegradable material for medical applications due to its non-toxicity, low density and good mechanical properties. The fast degradation rate of magnesium can be tailored using alloy design. The combined addition of Sr and Ca results in a good combination of mechanical and corrosion properties; the alloy compositions with the best performance are Mg-0.5Sr and Mg-0.3Sr-0.3Ca. In this study, we investigated an important effect, namely thermal treatment (at 400 °C), on alloy properties. The bio-corrosion of the alloys was analyzed via in vitro corrosion tests in simulated body fluid (SBF); the mechanical properties were studied through tensile, compression and three-point bending tests in two alloy conditions, as-cast and heat-treated. We showed that 8h of heat treatment increases the corrosion rate of Mg-0.5Sr very rapidly and decreases its mechanical strength. The same treatment does not significantly change the properties of Mg-0.3Sr-0.3Ca. An in-depth microstructural investigation via transmission electron microscopy, scanning electron microscopy, electron probe micro-analysis and X-ray diffraction elucidated the effects of the thermal exposure. Microstructural characterization revealed that Mg-0.3Sr-0.3Ca has a new intermetallic phase that is stable after 8h of thermal treatment. Longer thermal exposure (24h) leads to the dissolution of this phase and to its gradual transformation to the equilibrium phase Mg17Sr2, as well as to a loss of mechanical and corrosion properties. The ternary alloy shows better thermal stability than the binary alloy, but the manufacturing processes should aim to not exceed exposure to high temperatures (400 °C) for prolonged periods (over 24 h). Copyright © 2014 Elsevier B.V. All rights reserved.

Nd:YAG laser associated with metal salts solutions in the treatment of dentinal hypersensitivity; O laser de Nd:YAG associado a solucoes de sais metalicos no tratamento da hipersensibilidade dentinaria

Energy Technology Data Exchange (ETDEWEB)

Glauche, Carlos Eugenio Correia

2001-07-01

The objective of this study was to observe the ultrastructural changes caused by the radiation of Nd:YAG laser on the tooth tissue and determine qualitatively the presence of Sn{sup ++}, Sr{sup ++} and F{sup -}, inside the dentin, being it irradiated or not. Ten molar teeth recently extracted were cut into 2 mm discs. The samples were soaked in a EDTA solution at 17% for 2 minutes and divided into five groups. Group I: the samples were irradiated with Nd:YAG laser (1,5 W, 100 mJ, 15 Hz, 150 {mu}s and 125 J/cm{sup 2}) and after that, a treatment with an SnF{sub 2} aqueous solution at 10% for 30 minutes. Group II: the samples got laser irradiation with the same parameters and then a treatment with an SrCl{sub 2} solution at 10% as a toothpaste (Sensodyne{sup TM}) for 30 minutes. Group III: the samples just got a treatment with a SnF{sub 2} aqueous solution at 10% for 30 minutes. Group IV: the samples just got a treatment with a SrCl{sub 2} toothpaste (Sensodyne{sup TM}) for 30 minutes. Group V: samples that just got laser irradiation in the parameters above mentioned. Then, all samples were prepared for scanning electronic microscopy (SEM) and the samples of groups I, II, III and IV for energy dispersive X-ray microanalysis (EDX). The ultrastructure aspect of the dentin showed the surface totally altered by the irradiation. Pits and whitish globules were found amidst an heterogenous and rough structure, due to the melting and resolidification of the dental structure. Craters were also observed. Carbonization areas were absent. Ions Sn{sup ++} were found at a depth of 250 {mu}m in the samples of group I (Nd:YAG + SnF{sub 2}), whereas in the samples of group III, Sn{sup ++} were not found deeper than 100 {mu}m. Sr{sup ++} could be detected at least at 500 {mu}m in the inner dentin in the samples of group II (Nd:YAG + SrCl{sub 2}). However, Sn{sup ++} were not found at 50 {mu}m in group IV samples. Ions F{sup -} were just found in the irradiated samples of group I

Preparation and characterization of Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite for bone repair application

Directory of Open Access Journals (Sweden)

Hossein Mohammadi

2015-07-01

Full Text Available Objective(s: Hardystonite (HT is Zn-modified silicate bioceramics with promising results for bone tissue regeneration. However, HT possesses no obvious apatite formation. Thus, in this study we incorporated Sr and Ti into HT to prepare Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite and evaluated its in vitro bioactivity with the purpose of developing a more bioactive bone substitute material. Materials and methods:The HT and Sr-Ti-HT were prepared by mechanical milling and subsequent heat treatment. Calcium oxide (CaO, zinc oxide (ZnO and silicon dioxide (SiO2 (all from Merck were mixed with molar ratio of 2:1:2. The mixture of powders mixture was then milled in a planetary ball mill for 20 h. In the milling run, the ball-to-powder weight ratio was 10:1 and the rotational speed was 200 rpm. After synthesis of HT, 3% nanotitanium dioxide (TiO2, Degussa and 3% strontium carbonate (SrCO3, Merck were added to HT and then the mixture was ball milled and calcined at 1150°C for 6 h. Simultaneous thermal analysis (STA, X-ray diffraction (XRD, Transmission electron microscopy (TEM and Fourier transform infra-red spectroscopy (FT-IR performed to characterize the powders. Results:XRD and FT-IR confirmed the crystal phase and silicate structure of HT and TEM images demonstrated the nanostructure of powders. Further, Sr-Ti-HT induced apatite formation and showed a higher human mesenchymal stem cell (hMSCs adhesion and proliferation compared to HT. Conclusion:Our study revealed that Sr-Ti-HT with a nanostructured crystal structure of 50 nm, can be prepared by mechanical activation to use as biomaterials for orthopedic applications.

Comparison of a Simple Angiographic Approach With a Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery Score-Based Approach for Left Main Coronary Artery Stenting: A Pooled Analysis of Serial PRECOMBAT (Premier of Randomized Comparison of Bypass Surgery Versus Angioplasty Using Sirolimus-Eluting Stent in Patients With Left Main Coronary Artery Disease) Studies.

Science.gov (United States)

Lee, Pil Hyung; Lee, Jong-Young; Lee, Cheol Whan; Kim, Seon-Ok; Ahn, Jung-Min; Park, Duk-Woo; Kang, Soo-Jin; Lee, Seung-Whan; Kim, Young-Hak; Park, Seong-Wook; Park, Seung-Jung

2018-01-01

The applicability of Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery scores to left main coronary artery disease (CAD) has been questioned. A simplified alternative is needed for guiding decision making. We evaluated the prognostic value of a simplified angiographic classification in comparison with a Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score-based approach for patients with left main CAD undergoing drug-eluting stent implantation. The proposed approach classified left main CAD as either extensive (n=819), defined as left main bifurcation lesions with an involvement of ostial left circumflex artery or as any left main lesion plus multivessel CAD, or limited (n=453), defined as ostial/midshaft lesions or left main bifurcation lesions without an involvement of ostium of left circumflex artery, alone or plus 1-vessel disease. The databases from 4 prospective Premier of Randomized Comparison of Bypass Surgery versus Angioplasty Using Sirolimus-Eluting Stent in Patients with Left Main Coronary Artery Disease studies were pooled, and the primary outcome was a major adverse cardiac event, defined as death, myocardial infarction, or repeat revascularization. During follow-up (median 38 months; interquartile range, 36-61 months), the risk for major adverse cardiac event was significantly higher with extensive than with limited left main CAD (adjusted hazard ratio, 2.13; 95% confidence interval, 1.54-2.94; P Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery score tertiles did not effectively stratify these 2 outcome measures. Compared with Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery scores, the simpler angiographic approach provided better discrimination for future cardiovascular events in patients with left main CAD undergoing drug-eluting stent implantation. © 2018 American Heart Association, Inc.

Nuclear structure of 88Sr and 90Zr investigated by (e,e') and (p,p') reactions

International Nuclear Information System (INIS)

Bijl, L.T. van der.

1982-01-01

In this thesis the results are presented and discussed from two experiments, performed to investigate the nuclear structure of two N = 50 nuclei: a high resolution inelastic proton scattering experiment on 90 Zr, described in chapter II, and a high resolution inelastic electron scattering experiment on 88 Sr, described in chapters III and IV. The results obtained in the 88 Sr(e,e') experiment for the 1 + state at 3.486 MeV excitation energy are described separately in chapter V. The 90 Zr(p,p') experiment was performed at a bombarding energy of 25 MeV with a resolution of 12 to 16 keV. The 88 Sr(e,e') measurements were performed at two laboratories with an overall resolution between 20 and 60 keV. (Auth.)

Interim process report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Sellin, Patrick

2004-08-01

This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses

Interim process report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Sellin, Patrick (ed.)

2004-08-01

This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses.

Geochemical tracing of As pollution in the Orbiel Valley (southern France): 87Sr/86Sr as a tracer of the anthropogenic arsenic in surface and groundwater.

Science.gov (United States)

Khaska, Mahmoud; Le Gal La Salle, Corinnne; Lancelot, Joël; Verdoux, Patrick; Boutin, René

2014-05-01

results from redox potential (Eh) measurements in both surface and groundwater. Hence, 87Sr/86Sr appears as an excellent tracer of the origin of pollution associated with CaO treatment widely used in many water treatment processes.

[Diversity and community structure of endophytic fungi from Taxus chinensis var. mairei].

Science.gov (United States)

2014-07-01

A total of 628 endophytic fungi were isolated from 480 tissue segments of needles and branches of Taxus chinensis var. mairei. According to morphological characteristics and ITS sequences, they represented 43 taxa in 28 genera, of which 10 Hyphomycetes, 20 Coelomycetes, 12 Ascomycetes and 1 unknown fungus. Phomopsis mali was confirmed as the dominant species. In accordance with relative frequency, Alternaria alternata, Aureobasidium pullulans, Colletotrichum boninense, C. gloeosporioides, Epicoccum nigrum , Fungal sp., Fusarium lateritium, Glomerella cingulata, Magnaporthales sp. , Nigrospora oryzae, Pestalotiopsis maculiformans, P. microspora, Peyronellaea glomerata and Xylaria sp. 1 were more common in T. chinensis var. mairei. T. chinensis var. mairei were severely infected by endophytic fungi. Endophytic fungi were found in 81 percent of plant tissues with a high diversity. Distribution ranges of endophytic fungi were influenced by tissue properties. The colonization rate, richness, diversity of endophytic fungi in needles were obviously lower than in branches, and kinds of endophytic fungi between branches were more similar than those in needles, thus endophytic fungi had tissue preference. In addition, tissue age influenced the community structure of endophytic fungi. The elder branch tissues were, the higher colonization rate, richness, diversity of endophytic fungi were. Systematic studying the diversity and community structure of endophytic fungi in T. chinensis var. mairei and clarifying their distribution regularity in plant tissues would offer basic data and scientific basis for their development and utilization. Discussing the presence of fungal pathogens in healthy plant tissues would be of positive significance for source protection of T. chinensis var. mairei.

Under-recognition and under-treatment of DSM-IV classified mood and anxiety disorders among disability claimants

NARCIS (Netherlands)

Cornelius, Lammert; van der Klink, Jac J. L.; Brouwer, Sandra; Groothoff, Johan W.

2014-01-01

Purpose: This study aimed to examine under-recognition, under-treatment and severity of under-treated DSM-IV mood and anxiety disorders among disability claimants. Methods: In a representative sample of Dutch disability claimants (n = 346), registry codes certified according to the International

Double-blind, placebo-controlled pilot study of adjunctive quetiapine SR in the treatment of PMS/PMDD.

Science.gov (United States)

Jackson, Christine; Pearson, Brenda; Girdler, Susan; Johnson, Jacqueline; Hamer, Robert M; Killenberg, Susan; Meltzer-Brody, Samantha

2015-11-01

Premenstrual dysphoric disorder (PMDD), a more severe form of premenstrual syndrome (PMS), afflicts 5-8% of reproductive age women and results in significant functional impairment. We conducted a double-blind, placebo-controlled trial of adjunctive quetiapine in patients with PMS/PMDD who had inadequate response to selective serotonin reuptake inhibitor/serotonin-norepinephrine reuptake inhibitor therapy for their symptoms. A PMS/PMDD diagnosis was confirmed by 2-month prospective diagnostic assessment of PMS/PMDD using the Prospective Record of the Impact and Severity of Premenstrual Symptoms (PRISM) calendar. Women were randomized equally to receive quetiapine sustained-release (SR) or placebo (25-mg starting dose) during the luteal phase for 3 months. Outcome variables included the Hamilton Depression and Anxiety Scales, Clinical Global Impression Scale, and PRISM. Twenty women were enrolled in the treatment phase. Although the study was underpowered, greater reductions in luteal phase mood ratings were observed in the quetiapine group on the 17-item Hamilton Depression Rating Scale, Clinical Global Impression improvement rating, and PRISM daily score. The quetiapine group showed most improvement in symptoms of mood lability, anxiety, and irritability. This small double-blind study suggests that adjunctive treatment with quetiapine SR may be a useful addition to selective serotonin reuptake inhibitor therapy in women with PMS/PMDD by reducing symptoms and improving quality of life. Copyright © 2015 John Wiley & Sons, Ltd.

Quality control methods of strontium chloride 89SrCl2, radiopharmaceutical for palliative treatment of bone metastases

International Nuclear Information System (INIS)

Deptula, C.Z.; Kempisty, T.; Markiewicz, A.; Mikolajczak, R.; Stefancyk, S.; Terlikowska, T.; Zulczyk, W.

1997-01-01

Strontium chloride, 89 SrCI 2 , a radiopharmaceutical used for palliative therapy of bone metastases from breast and prostate cancer is produced by irradiation in a nuclear reactor. The analytical quality control procedures are established to confirm the radionuclidic purity of the preparation, its chemical composition and specific activity. Chemical concentration of strontium in the product is determined by complexometry with arsenazo III and chlorides assay by potentiometric titration with silver nitrate. The contamination with chemical impurities is determined by DC graphite spark spectrography. The specific activity and isotonicity of the solution are corrected by addition of natural SrCI 2 and NaCI. 90 Sr is produced in the 89 Sr(n,γ) 90 Sr reaction contributes to impurities. It decays to 90 Y and the activity of 90 Sr can be calculated from the activity of 90 Y. The extraction chromatography on nonionic acrylic ester polymer coated with organic solutions of selective features (Spec resins for Eichrom) is applied for separation of radionuclides. The extraction chromatography system consisting of two columns: strontium selective resin and rare earth elements selective resin was used for separation of 90 Y from 90 Sr in the 89 SrCI 2 solution. The 90 Y and 90 Sr carrier-free solutions used as tracers helped for determination of extraction conditions and efficiency. The concentration of 90 Sr determined in the analysed solution is at the level of 2.10 -4 % which conforms with the data calculated from irradiation parameters. The obtained product, strontium chloride 89 SrCI 2 for injection, forms a sterile and isotonic water solution (pH - 4-7) with specific activity of 89 Sr in the range from 3.5 to 6.3. MBq/mg and radioactive concentration of 37.5 MBq/ml. The radionuclidic purity of the obtained preparations is at the level of 99.9% with respect to 89 Sr

Metastable honeycomb SrTiO_3/SrIrO_3 heterostructures

International Nuclear Information System (INIS)

Anderson, T. J.; Ryu, S.; Podkaminer, J. P.; Ma, Y.; Eom, C. B.; Zhou, H.; Xie, L.; Irwin, J.; Rzchowski, M. S.; Pan, X. Q.

2016-01-01

Recent theory predictions of exotic band topologies in (111) honeycomb perovskite SrIrO_3 layers sandwiched between SrTiO_3 have garnered much attention in the condensed matter physics and materials communities. However, perovskite SrIrO_3 film growth in the (111) direction remains unreported, as efforts to synthesize pure SrIrO_3 on (111) perovskite substrates have yielded films with monoclinic symmetry rather than the perovskite structure required by theory predictions. In this study, we report the synthesis of ultra-thin metastable perovskite SrIrO_3 films capped with SrTiO_3 grown on (111) SrTiO_3 substrates by pulsed laser deposition. The atomic structure of the ultra-thin films was examined with scanning transmission electron microscopy (STEM), which suggests a perovskite layering distinct from the bulk SrIrO_3 monoclinic phase. In-plane 3-fold symmetry for the entire heterostructure was confirmed using synchrotron surface X-ray diffraction to measure symmetry equivalent crystal truncation rods. Our findings demonstrate the ability to stabilize (111) honeycomb perovskite SrIrO_3, which provides an experimental avenue to probe the phenomena predicted for this material system.

Experiences with the determination of Sr-89 and Sr-90 using fast methods; Erfahrungen bei der Bestimmung von {sup 89}Sr und {sup 90}Sr mittels Schnellmethoden

Energy Technology Data Exchange (ETDEWEB)

Kowalik, C.; Fueger, J. [Thueringer Landesanstalt fuer Umwelt und Geologie, Jena (Germany). Landesmessstelle fuer Umweltradioaktivaet

2014-01-20

Quick methods of the measurement of {sup 89}Sr and {sup 90}Sr have a great importance in the supervision of the environmental radioactivity. It is necessary to receive in short time dependable analytical data to be able to carry out suitable assessments or to give recommendations. The aim of the investigations was to be guaranteed the demands for these methods (test preparation, measurement and evaluation). The use of the solid phase extraction by means of commercial Sr Resin trademark columns (4.4' (5')-Di-tert-butylcyclohexanol-18-kronen-6-aether) (Triskem) to the radiochemical separation of the Sr isotopes was suitable. The measurements occurred to the FHT 770 T12 - Multi Low Level Alpha/Beta Sample Counter (Thermo Scientific). The results contain the summary activities of all available Sr isotopes, as for example {sup 89}Sr and {sup 90}Sr. The calculations of the single activities occur about the mathematical algorithm of the linear development on the basis of the works of G. Kanisch. The first results show, this method is suitable for the analysis of {sup 89}Sr and {sup 90}Sr and is used therefore in future in Thuringia.

Mechanistic, Mutational, and Structural Evaluation of a Taxus Phenylalanine Aminomutase

Energy Technology Data Exchange (ETDEWEB)

Feng, Lei; Wanninayake, Udayanga; Strom, Susan; Geiger, James; Walker, Kevin D. (MSU)

2014-10-02

The structure of a phenylalanine aminomutase (TcPAM) from Taxus canadensis has been determined at 2.4 {angstrom} resolution. The active site of the TcPAM contains the signature 4-methylidene-1H-imidazol-5(4H)-one prosthesis, observed in all catalysts of the class I lyase-like family. This catalyst isomerizes (S)-{alpha}-phenylalanine to the (R)-{beta}-isomer by exchange of the NH{sub 2}/H pair. The stereochemistry of the TcPAM reaction product is opposite of the (S)-{beta}-tyrosine made by the mechanistically related tyrosine aminomutase (SgTAM) from Streptomyces globisporus. Since TcPAM and SgTAM share similar tertiary- and quaternary-structures and have several highly conserved aliphatic residues positioned analogously in their active sites for substrate recognition, the divergent product stereochemistries of these catalysts likely cannot be explained by differences in active site architecture. The active site of the TcPAM structure also is in complex with (E)-cinnamate; the latter functions as both a substrate and an intermediate. To account for the distinct (3R)-{beta}-amino acid stereochemistry catalyzed by TcPAM, the cinnamate skeleton must rotate the C{sub 1}-C{sub {alpha}} and C{sub ipso}-C{sub {beta}} bonds 180{sup o} in the active site prior to exchange and rebinding of the NH{sub 2}/H pair to the cinnamate, an event that is not required for the corresponding acrylate intermediate in the SgTAM reaction. Moreover, the aromatic ring of the intermediate makes only one direct hydrophobic interaction with Leu-104. A L104A mutant of TcPAM demonstrated an 1.5-fold increase in k{sub cat} and a decrease in K{sub M} values for sterically demanding 3'-methyl-{alpha}-phenylalanine and styryl-{alpha}-alanine substrates, compared to the kinetic parameters for TcPAM. These parameters did not change significantly for the mutant with 4'-methyl-{alpha}-phenylalanine compared to those for TcPAM.

New stent design for use in small coronary arteries during percutaneous coronary intervention

Directory of Open Access Journals (Sweden)

Juan F Granada

2010-10-01

Full Text Available Juan F Granada1, Barbara A Huibregtse2, Keith D Dawkins21The Jack H Skirball Center for Cardiovascular Research, Cardiovascular Research Foundation, Columbia University Medical Center, New York, NY, USA; 2Boston Scientific Corporation, Natick, MA, USAAbstract: Patients with diabetes mellitus, of female gender, increased age, and/or with peripheral vascular disease often develop coronary stenoses in small caliber vessels. This review describes treatment of these lesions with the paclitaxel-eluting 2.25 mm TAXUS® Liberté® Atom™ stent. Given the same stent composition, polymer, antirestenotic drug (paclitaxel, and release kinetics as the first-generation 2.25 mm TAXUS® Express® Atom™ stent, the second-generation TAXUS Liberté Atom stent incorporates improved stent design characteristics, including thinner struts (0.0038 versus 0.0052 inches, intended to increase conformability and deliverability. In a porcine noninjured coronary artery model, TAXUS Liberté Atom stent implantation in small vessels demonstrated complete strut tissue coverage compared with the bare metal stent control, suggesting a similar degree of tissue healing between the groups at 30, 90, and 180 days. The prospective, single-armed TAXUS ATLAS Small Vessel trial demonstrated improved instent late loss (0.28 ± 0.45 versus 0.84 ± 0.57 mm, P < 0.001, instent binary restenosis (13.0% versus 38.1%, P < 0.001, and target lesion revascularization (5.8% versus 17.6%, P < 0.001 at nine months with the TAXUS Liberté Atom stent as compared with the bare metal Express stent control, with similar safety measures between the two groups. The TAXUS Liberté Atom also significantly reduced nine-month angiographic rates of both instent late loss (0.28 ± 0.45 versus 0.44 ± 0.61 mm, P = 0.03 and instent binary restenosis (13.0% versus 25.9%, P = 0.02 when compared with the 2.25 mm TAXUS Express Atom control. The observed reduction in target lesion revascularization with the TAXUS

Antidepressive and BDNF effects of enriched environment treatment across ages in mice lacking BDNF expression through promoter IV

Science.gov (United States)

Jha, S; Dong, B E; Xue, Y; Delotterie, D F; Vail, M G; Sakata, K

2016-01-01

Reduced promoter IV-driven expression of brain-derived neurotrophic factor (BDNF) is implicated in stress and major depression. We previously reported that defective promoter IV (KIV) caused depression-like behavior in young adult mice, which was reversed more effectively by enriched environment treatment (EET) than antidepressants. The effects of promoter IV-BDNF deficiency and EET over the life stages remain unknown. Since early-life development (ED) involves dynamic epigenetic processes, we hypothesized that EET during ED would provide maximum antidepressive effects that would persist later in life due to enhanced, long-lasting BDNF induction. We tested this hypothesis by determining EET effects across three life stages: ED (0–2 months), young adult (2–4 months), and old adult (12–14 months). KIV mice at all life stages showed depression-like behavior in the open-field and tail-suspension tests compared with wild-type mice. Two months of EET reduced depression-like behavior in ED and young adult, but not old adult mice, with the largest effect in ED KIV mice. This effect lasted for 1 month after discontinuance of EET only in ED mice. BDNF protein induction by EET in the hippocampus and frontal cortex was also the largest in ED mice and persisted only in the hippocampus of ED KIV mice after discontinuance of EET. No gender-specific effects were observed. The results suggest that defective promoter IV causes depression-like behavior, regardless of age and gender, and that EET during ED is particularly beneficial to individuals with promoter IV-BDNF deficiency, while additional treatment may be needed for older adults. PMID:27648918

Incorporation of sulfate or selenate groups into oxotellurates(IV). I. Calcium, cadmium, and strontium compounds

Energy Technology Data Exchange (ETDEWEB)

Weil, Matthias; Shirkhanlou, Mahdi [Institute for Chemical Technologies and Analytics, Division Structural Chemistry, TU Wien, Vienna (Austria)

2017-02-15

Seven new mixed oxochalcogenate compounds in the systems M{sup II}/X{sup VI}/Te{sup IV}/O/(H), (M{sup II} = Ca, Cd, Sr; X{sup VI} = S, Se) were obtained under hydrothermal conditions (210 C, one week). Crystal structure determinations based on single-crystal X-ray diffraction data revealed the compositions Ca{sub 3}(SeO{sub 4})(TeO{sub 3}){sub 2}, Ca{sub 3}(SeO{sub 4})(Te{sub 3}O{sub 8}), Cd{sub 3}(SeO{sub 4})(Te{sub 3}O{sub 8}), Cd{sub 3}(H{sub 2}O)(SO{sub 4})(Te{sub 3}O{sub 8}), Cd{sub 4}(SO{sub 4})(TeO{sub 3}){sub 3}, Cd{sub 5}(SO{sub 4}){sub 2}(TeO{sub 3}){sub 2}(OH){sub 2}, and Sr{sub 3}(H{sub 2}O){sub 2}(SeO{sub 4})(TeO{sub 3}){sub 2} for these phases. Peculiar features of the crystal structures of Ca{sub 3}(SeO{sub 4})(TeO{sub 3}){sub 2}, Ca{sub 3}(SeO{sub 4})(Te{sub 3}O{sub 8}), Cd{sub 3}(SeO{sub 4})(Te{sub 3}O{sub 8}), Cd{sub 3}(H{sub 2}O)(SO{sub 4})(Te{sub 3}O{sub 8}), and Sr{sub 3}(H{sub 2}O){sub 2}(SeO{sub 4})(TeO{sub 3}){sub 2} are metal-oxotellurate(IV) layers connected by bridging XO{sub 4} tetrahedra and/or by hydrogen-bonding interactions involving hydroxyl or water groups, whereas Cd{sub 4}(SO{sub 4})(TeO{sub 3}){sub 3} and Cd{sub 5}(SO{sub 4}){sub 2}(TeO{sub 3}){sub 2}(OH){sub 2} crystallize as framework structures. Common to all crystal structures is the stereoactivity of the Te{sup IV} electron lone pair for each oxotellurate(IV) unit, pointing either into the inter-layer space, or into channels and cavities in the crystal structures. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Rapid method for determining Sr-89 and Sr-90 using Cherenkov and proportional counting; Schnellmethode zur Bestimmung von SR-89 und SR-90 durch Cerenkov- und Proportionalzaehlermessungen

Energy Technology Data Exchange (ETDEWEB)

Lange, S.; Wende, C.; Schwokowski, R.; Alisch-Mark, M.; Abraham, A.; Heinrich, T. [Staatliche Betriebsgesellschaft fuer Umwelt und Landwirtschaft, Radebeul (Germany)

2016-07-01

A rapid method for determining Sr-89 and Sr-90 in water, milk and biological samples has been developed and tested. After sample preparation strontium is separated by extraction chromatography using Sr resin. Eluate is divided and transfered to LSC vial and filter paper by SrCO{sub 3} precipitation. A Hidex 300 SL TDCR liquid scintillation counter and Thermo Fisher low level proportional counter have been used. Chemical yield of Sr-85 tracer is determined by Gamma spectroscopy. Uncertainty budget, decision threshold and detection limit are calculated in accordance with GUM and ISO 11929.

Real-time {sup 90}Sr Counter

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Naomi; Kawai, Hideyuki; Kodama, Satoshi; Kobayashi, Atsushi; Tabata, Makoto; Ito, Hiroshi [Graduate School of Science, Chiba University, Chiba, (Japan); Han, Soorim [Graduate School of Science, Chiba University, Chiba, (Japan); National Institute of Radiological Science, Chiba, (Japan)

2015-07-01

Radioisotopes have been emitted around Japan due to a nuclear accident at the Fukushima Daiichi nuclear power station in March 2011. A problem is the contaminated water including the atomic nucleus which relatively has a long half- life time and soluble such as {sup 90}Sr, {sup 137}Cs. Internal exposures by {sup 90}Sr are more dangerous than {sup 137}Cs's because Sr has effective half-life time of 18 years and property of accumulation in a born. We have developed real-time {sup 90}Sr counter which is sensitive beta-ray of maximum kinematic energy of 2.28 MeV from {sup 90}Sr and insensitive of beta-ray of maximum kinematic energy of 1.17 MeV and gamma-ray from {sup 90}Sr by Cherenkov detection. This counter composes of Cerenkov counter, trigger scintillation counter and veto counter. Silica aerogel for Cherenkov counter can obtain refractive index between 1.017 and 1.049 easily. And wavelength shifting fiber (WLSF) is used as a light guide for extending effective area and producing lower cost. A mechanism of the identification of {sup 90}Sr is explained in following. In case of {sup 90}Sr, when the trigger counter reacts on the beta-ray from {sup 90}Sr, aerogel emits the Cherenkov light and WLSF reacts and read the Cherenkov light. On the other hand, in case of {sup 137}Cs, the trigger counter reacts on the beta-ray, aerogel stops the beta- ray and Cherenkov light is not emitted. Therefore, aerogel has a function as a radiator and shielding material. the gamma-ray is not reacted on the lower density detector. Cosmic rays would be also reacted by the veto counter. A prototype counter whose the effective area is 30 cm x 10 cm was obtained (2.0±1.2){sup 3} of mis-identification as {sup 137}Cs/{sup 90}Sr. Detection limit in the surface contamination inspection depends on measurement time and effective area mainly. The sensitivity of wide range, 10{sup -2} - 10{sup 4} Bq/cm{sup 2}, is obtained by adjustment of detection level in circuit of this counter. A lower

Thermal exposure effects on the in vitro degradation and mechanical properties of Mg–Sr and Mg–Ca–Sr biodegradable implant alloys and the role of the microstructure

Energy Technology Data Exchange (ETDEWEB)

Bornapour, M., E-mail: mandana.bornapour@mail.mcgill.ca [McGill University, Materials Engineering, Montreal, QC (Canada); Celikin, M. [INRS, Energy Materials Telecommunications Research Centre, Varennes, QC (Canada); Pekguleryuz, M. [McGill University, Materials Engineering, Montreal, QC (Canada)

2015-01-01

Magnesium is an attractive biodegradable material for medical applications due to its non-toxicity, low density and good mechanical properties. The fast degradation rate of magnesium can be tailored using alloy design. The combined addition of Sr and Ca results in a good combination of mechanical and corrosion properties; the alloy compositions with the best performance are Mg–0.5Sr and Mg–0.3Sr–0.3Ca. In this study, we investigated an important effect, namely thermal treatment (at 400 °C), on alloy properties. The bio-corrosion of the alloys was analyzed via in vitro corrosion tests in simulated body fluid (SBF); the mechanical properties were studied through tensile, compression and three-point bending tests in two alloy conditions, as-cast and heat-treated. We showed that 8 h of heat treatment increases the corrosion rate of Mg–0.5Sr very rapidly and decreases its mechanical strength. The same treatment does not significantly change the properties of Mg–0.3Sr–0.3Ca. An in-depth microstructural investigation via transmission electron microscopy, scanning electron microscopy, electron probe micro-analysis and X-ray diffraction elucidated the effects of the thermal exposure. Microstructural characterization revealed that Mg–0.3Sr–0.3Ca has a new intermetallic phase that is stable after 8 h of thermal treatment. Longer thermal exposure (24 h) leads to the dissolution of this phase and to its gradual transformation to the equilibrium phase Mg{sub 17}Sr{sub 2}, as well as to a loss of mechanical and corrosion properties. The ternary alloy shows better thermal stability than the binary alloy, but the manufacturing processes should aim to not exceed exposure to high temperatures (400 °C) for prolonged periods (over 24 h). - Highlights: • Thermal exposure decreases the mechanical properties and increases the biocorrosion rate of Mg–0.5Sr. • Thermally stable globular Ca/Sr-rich phases form in the Mg–0.3Sr–0.3Ca alloy. • Mg–0.3Sr–0.3Ca

Thermal exposure effects on the in vitro degradation and mechanical properties of Mg–Sr and Mg–Ca–Sr biodegradable implant alloys and the role of the microstructure

International Nuclear Information System (INIS)

Bornapour, M.; Celikin, M.; Pekguleryuz, M.

2015-01-01

Magnesium is an attractive biodegradable material for medical applications due to its non-toxicity, low density and good mechanical properties. The fast degradation rate of magnesium can be tailored using alloy design. The combined addition of Sr and Ca results in a good combination of mechanical and corrosion properties; the alloy compositions with the best performance are Mg–0.5Sr and Mg–0.3Sr–0.3Ca. In this study, we investigated an important effect, namely thermal treatment (at 400 °C), on alloy properties. The bio-corrosion of the alloys was analyzed via in vitro corrosion tests in simulated body fluid (SBF); the mechanical properties were studied through tensile, compression and three-point bending tests in two alloy conditions, as-cast and heat-treated. We showed that 8 h of heat treatment increases the corrosion rate of Mg–0.5Sr very rapidly and decreases its mechanical strength. The same treatment does not significantly change the properties of Mg–0.3Sr–0.3Ca. An in-depth microstructural investigation via transmission electron microscopy, scanning electron microscopy, electron probe micro-analysis and X-ray diffraction elucidated the effects of the thermal exposure. Microstructural characterization revealed that Mg–0.3Sr–0.3Ca has a new intermetallic phase that is stable after 8 h of thermal treatment. Longer thermal exposure (24 h) leads to the dissolution of this phase and to its gradual transformation to the equilibrium phase Mg 17 Sr 2 , as well as to a loss of mechanical and corrosion properties. The ternary alloy shows better thermal stability than the binary alloy, but the manufacturing processes should aim to not exceed exposure to high temperatures (400 °C) for prolonged periods (over 24 h). - Highlights: • Thermal exposure decreases the mechanical properties and increases the biocorrosion rate of Mg–0.5Sr. • Thermally stable globular Ca/Sr-rich phases form in the Mg–0.3Sr–0.3Ca alloy. • Mg–0.3Sr–0.3Ca maintains

Forest structure of Mediterranean yew (Taxus baccata L. populations and neighbor effects on juvenile yew performance in the NE Iberian Peninsula

Directory of Open Access Journals (Sweden)

Pere Casals

2015-12-01

Full Text Available Aim of study: In the Mediterranean region, yew (Taxus baccata L. usually grows with other tree species in mixed forests. Yew recruitment and juvenile growth may depend on the structure of the forest and the net balance between competition for soil water and nutrients with neighbors and facilitation that these neighbors exert by protecting the plants from direct sun exposure. This study aims, at a regional scale, to analyze the structure of forests containing yew, and, on an individual level, to analyze the effect of the surrounding vegetation structure on the performance of yew juveniles.Area of study: The structural typologies of yew populations were defined based on field inventories conducted in 55 plots distributed in 14 localities in the North-Eastern (NE Iberian Peninsula, covering a wide range of yew distribution in the area. In a second step, an analysis of neighboring species' effects on juveniles was conducted based on the data from 103 plots centered in yew juveniles in five localities.Main Results: A cluster analysis classified the inventoried stands into four forest structural types: two multi-stratified forests with scattered yew and two yew groves. Multiple regression modeling showed that the δ13C measured in last year's leaves positively relates to the basal area of conifer neighbors, but negatively with the cover of the yew crown by other trees.Research highlights: At a stand-level, the density of recruits and juveniles (625 ± 104 recruits ha-1, 259 ± 55 juveniles ha-1 in mixed forests was found to be higher than that on yew dominant stands (181 ± 88 recruits ha-1 and 57 ± 88 juveniles ha-1. At an individual-level, the water stress (estimated from leaf δ13C of yew juveniles seems alleviated by the crown cover by neighbors while it increases with the basal area of conifers. Yew conservation should focus on selective felling for the reduction of basal area of neighbors surrounding the target tree, but avoid affecting the

The effect of phytohormones on the 133Cs and 88Sr accumulation in oilseed rape

International Nuclear Information System (INIS)

Guo Mengluo; Xu Changhe; Li Xinlei; Wang Dan

2011-01-01

The effect of uptake and distribution of 133 Cs and 88 Sr in the common plant-India mustard (Brassica napus L.) by exogenous phytohormones (Gibberelin-A 3 GA 3 , Salicylates, SA, 3-indole acetic acid, IAA) treatments were studied by using hydroponic experiment. The results shown as follows: the biomass of above-ground and that of roots of oilseed rape were obviously higher than that of contrary (non-hormone), and the accumulation of 133 Cs and 88 Sr increased as well, under the three phytohormones treatments. The distribution sequence of 133 Cs and 88 Sr in oilseed rape was roots>above-grounds, and the contents was 1 3 3 Cs> 88 Sr. The accumulation ability of phytohormones was GA>SA>IAA, the accumulation of 133 Cs or 88 Sr increased with the phytohormone concentration. The treatment of mid-level of Gibberelin-A 3 (500 mg/L) and Salicylates acid (500 μmol/L) increased the biomass, enrichment and the translocation factors under the low concentration of 133 Cs and 88 Sr stress (1 mmol/L). Therefore, the phyto-extraction efficiency was enhanced in oilseed rape by using exogenous phytohormones. (authors)

Environmental 90Sr measurements

Science.gov (United States)

Paul, M.; Berkovits, D.; Cecil, L.D.; Feldstein, H.; Hershkowitz, A.; Kashiv, Y.; Vogt, S.

1997-01-01

90Sr (T1/2 = 28.5 years) is a long-lived radionuclide produced in nuclear fission. Fast radiochemical detection of 90Sr in environmental samples is not feasible using current analytical methods. Accelerator Mass Spectrometry (AMS) measurements of 90Sr were made with the Rehovot 14UD Pelletron accelerator at a terminal voltage of 11 or 12 MV using our standard detection system. Injection of hydride ions (SrH3-) was chosen owing to high beam intensity and low Coulomb explosion effects. 90Sr ions were identified and discriminated from isobaric 90Zr by measuring time of flight, total energy and three independent energy-loss signals in an ionization chamber. A reference sample and a ground-water sample were successfully measured. The detection limit determined for a laboratory blank by the residual counts in the 90Sr region is 90Sr/Sr = 3 ?? 10-13, corresponding in practice to (2-4) ?? 10790Sr atoms or about 0.5-1 pCi/L in environmental water samples.

Evaluation of SR 97 regarding treatment of uncertainties in chemical systems

International Nuclear Information System (INIS)

Ekberg, C.

2000-01-01

below. Until today only one SKB-report has been published that explicitly mention the handling of uncertainties in solubility calculations. This report also includes the derivation of solubilities used in SR 97. In this report, the treatment of the general chemistry is, according to my judgement, of good quality. However, keeping in mind what has been done in the rest of the world in the context of uncertainty and sensitivity analysis, the handling of the uncertainties in this report is at the best rudimentary. The approach of using only one 'low' and one 'high' value for a given variable when judging its importance is not enough. Chemical speciation is in most cases not linear why the adopted procedure in SR 97 only gives a rough estimate, at the best. A more preferable method is to work from the bottom and upwards in the investigation. This means that an uncertainty analysis of e.g. radionuclide transport starts with the effects and role of different uncertainties in the solubility calculations. The results from these probabilistic solubility calculations will then be the probabilistic input for the further transport calculations. The discussion made in connection with distributions is bantering and rather irrelevant (although correct). It is said that since it is not possible to get distributions for all parameters and thus they are excluded from the probabilistic calculations by assuming that they can be represented by only two values. A more 'conservative' method would have been to assume uniform distributions for the radionuclide solubilities concerned and thus enhance the probability that solubilities far from the mean value would occur. The slightly inadequate method used in SR 97 make the conclusions regarding solubilities slightly suspicious. If there are no reliable probability distributions available it is even more essential that their importance is evaluated. As mentioned above, one can always assume a uniform distribution and assign to it a range of about

Maxdose-SR and popdose-SR routine release atmospheric dose models used at SRS

Energy Technology Data Exchange (ETDEWEB)

Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trimor, P. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-07-28

MAXDOSE-SR and POPDOSE-SR are used to calculate dose to the offsite Reference Person and to the surrounding Savannah River Site (SRS) population respectively following routine releases of atmospheric radioactivity. These models are currently accessed through the Dose Model Version 2014 graphical user interface (GUI). MAXDOSE-SR and POPDOSE-SR are personal computer (PC) versions of MAXIGASP and POPGASP, which both resided on the SRS IBM Mainframe. These two codes follow U.S. Nuclear Regulatory Commission (USNRC) Regulatory Guides 1.109 and 1.111 (1977a, 1977b). The basis for MAXDOSE-SR and POPDOSE-SR are USNRC developed codes XOQDOQ (Sagendorf et. al 1982) and GASPAR (Eckerman et. al 1980). Both of these codes have previously been verified for use at SRS (Simpkins 1999 and 2000). The revisions incorporated into MAXDOSE-SR and POPDOSE-SR Version 2014 (hereafter referred to as MAXDOSE-SR and POPDOSE-SR unless otherwise noted) were made per Computer Program Modification Tracker (CPMT) number Q-CMT-A-00016 (Appendix D). Version 2014 was verified for use at SRS in Dixon (2014).

Development of 90Sr-90Y generators

International Nuclear Information System (INIS)

Barrio, Graciela

2007-01-01

Yttrium-90 is a radioisotope of great interest in the field of Nuclear Medicine. It is considered one of the most important and most used radionuclides for radioimmunotherapeutical applications, especially promising for the treatment of certain types of cancer. Another important application of 90 Y is radio synovectomy. This radionuclide has a half-life of 64 hours, emits long range beta particles (maximum energy of 2.3 MeV) and decays, without intermediate nuclides, to a stable daughter. 90 Y may be obtained carrier-free, generated by the decay of its parent 90 Sr (half-life=28 years). 90 Sr is a product from uranium fission, and due to its long half-life, can be indefinitely used, which is certainly advantageous. It is present in great amounts, and needs to be processed and purified in order to be used as raw material for the generators. Generators of 90 Sr- 90 Y may thus be used during various months, due to 90 Sr long half-life. Several methods for the separation of 90 Y from 90 Sr by solvent extraction and ion exchange have been reported in literature. Thanks to its simplicity, ion exchange techniques have been more commonly used for this generator system. The main objective of this work was to develop a methodology for the preparation of 90 Sr- 90 Y generators, using cationic exchange resins. In such method, 90 Sr is strongly adsorbed in the resin and 90 Y is eluted by a 0.003 M EDTA solution. According to the quality control carried out, results showed that elution yields are greater than 65%, thus confirming the efficiency of the separation method used.

Treatment of proximal deep vein thrombosis with a novel synthetic compound (SR90107A/ORG31540) with pure anti-factor Xa activity - A phase II evaluation

NARCIS (Netherlands)

Buller, HR; Cariou, R; Gallus, A; Gent, M; Ginsberg, J; Prins, MH; Lensing, A; Levi, M; Nurmohammed, N; Hirsh, J; Roberts, R; ten Cate, JW; Decousus, H; Mismetti, P; Buchmuller, A; Charlet, [No Value; Viallon, A; van der Meer, J; Meinardi, [No Value; Meijer, K; Piovella, F; Barone, M; Beltrametti, C; Serafini, S; Kraaijenhagen, RA; Koopman, MMW; Jagt, HHT; Muller, MBR; Kooy, MV; Nauta, S; Gallus, AS; Coghlan, D; Rich, C; Prandoni, P; Scudeller, A; Scarano, L; Girolami, A; Baker, R; Tan, E; Cooney, J; Eikelboom, J; Ninet, J; Dolmazon, C; Madoux, MHG; Coppere, B; Nenci, GG; Agnelli, G; Falcinelli, F; Morini, M; d'Angelo, A

2000-01-01

Background-Patients with venous thromboembolism require initial treatment with an immediate-acting anticoagulant, low-molecular-weight heparin. We evaluated a novel synthetic factor Xa inhibitor (SR90107a/ORG31540) as an alternative treatment. Methods and Results-A randomized-parallel-group, phase

Neodymium-doped Sr5(PO4)3F and Sr5(VO4)3F

International Nuclear Information System (INIS)

Corker, D.L.; Nicholls, J.; Loutts, G.B.

1995-01-01

Neodymium-doped Sr 5 (PO 4 ) 3 F [neodymium strontium fluoride phosphate, (Nd,Sr) 5 (PO 4 ) 3 F] and neodymium-doped Sr 5 (VO 4 ) 3 F [neodymium strontium fluoride vanadate, (Nd,Sr) 5 (VO 4 ) 3 F] crystallize in space group P6 3 /m and are isostructural with calcium fluorophosphate, Ca 5 (PO 4 ) 3 F. There are two different Sr sites in Sr 5 (XO 4 ) 3 F, denoted Sr(1) and Sr(2). Using single-crystal X-ray diffraction the two structures were refined to R factors of 2.3 and 2.2%, respectively, showing that Nd is present at both Sr sites in (Sr,Nd) 5 (VO 4 ) 3 F but only at the Sr(2) site in (Sr,Nd) 5 (PO 4 ) 3 F. (orig.)

Is the Modern Marine 87Sr/86Sr Cycle Balanced?

Science.gov (United States)

Peucker-Ehrenbrink, B.

2017-12-01

The marine 87Sr/86Sr record is one of the best-reconstructed isotope records with thousands of high quality measurements spanning the past 800 million years. It records a global signal of tectonic, biotic and climatic processes on Earth. Yet despite decades of research we still do not know whether the current marine Sr budget is in steady state. Studies of the marine 88Sr/86Sr record indicate that sources and sinks do not balance. The magnitude and isotope composition of the terrestrial inputs are being debated, and the magnitude and temporal variability of unradiogenic contributions are not well constrained. Here I provide a revised assessment of all continental sources of Sr to the ocean, including river runoff, submarine groundwater discharge (Beck et al., 2013), dissolution of riverine suspended matter in seawater and dissolution of volcanic ash deposited on the ocean (Jones et al., 2012). I contrast continental sources of Sr with estimates of marine sources of Sr to seawater, specifically high- and low-temperature submarine hydrothermal fluids, as well as diffusive diagenetic fluxes. Best current data imply that unradiogenic submarine hydrothermal inputs to seawater are insufficient to balance the flux of radiogenic continental Sr. The revised assessment of riverine contributions is based on Sr data for almost 230 rivers, an increasing amount of time-series data for such rivers, as well as river discharge and sediment flux data for more than 2000 rivers. Regional sampling biases have been corrected with the aid of digital bedrock maps, specifically along the western margin of North America, East Africa and the large drainage region of Arabia, India and SE Asia. Significant uncertainty in the chemical and isotopic compositions of runoff from Greenland and East Africa remains. The main uncertainty in the budget, however, is related to the possibility that modern rivers do not represent the pre-anthropogenic (natural) state of continental runoff (e.g. Ganges

Antibacterial Activities of Endophytic Bacteria Isolated from Taxus brevifolia Against Foodborne Pathogenic Bacteria.

Science.gov (United States)

Islam, Nurul; Choi, Jaehyuk; Baek, Kwang-Hyun

2018-05-01

Endophytes are a potential source of novel bioactive compounds with medicinal properties. In this study, 41 endophytic bacteria (EB) were isolated from tissues of a medicinally important plant Taxus brevifolia (Pacific yew). The objective was to screen all the EB isolates for their antibacterial effects against five foodborne pathogenic bacteria: Bacillus cereus ATCC10876, Staphylococcus aureus ATCC12600, Listeria monocytogenes ATCC19115, Escherichia coli ATCC43890, and Salmonella Typhimurium ATCC19585. Among the EB isolates, T. brevifolia seed (TbS)-8, T. brevifolia fleshy part of fruit (TbFl)-10, T. brevifolia leaf (TbL)-22, TbS-29, and TbL-34 exerted significant antibacterial activity against the tested foodborne pathogens. Especially TbFl-10 showed the highest antibacterial activity against all the tested bacteria and was identified as Paenibacillus kribbensis (Pk). Furthermore, an ethyl acetate extract of Pk-TbFl-10 possessed antibacterial activities against the tested five foodborne pathogenic bacteria, with zones of inhibition from 15.71 ± 2.85 to 13.01 ± 2.12 mm. Scanning electron microscopy analysis revealed ruptured, lysed, shrunk, and swollen cells of all the tested foodborne pathogens treated with the ethyl acetate extract of Pk-TbFl-10, suggesting that a metabolite(s) of Pk-TbFl-10 penetrates the cell membrane and causes cell lysis leading to cell death. Our results indicate that Pk-TbFl-10 isolated from T. brevifolia can serve as a novel source of natural antibacterial agents against foodborne pathogenic bacteria, with potential applications in the pharmaceutical industry.

A population balance equation model of aggregation dynamics in Taxus suspension cell cultures.

Science.gov (United States)

Kolewe, Martin E; Roberts, Susan C; Henson, Michael A

2012-02-01

The nature of plant cells to grow as multicellular aggregates in suspension culture has profound effects on bioprocess performance. Recent advances in the measurement of plant cell aggregate size allow for routine process monitoring of this property. We have exploited this capability to develop a conceptual model to describe changes in the aggregate size distribution that are observed over the course of a Taxus cell suspension batch culture. We utilized the population balance equation framework to describe plant cell aggregates as a particulate system, accounting for the relevant phenomenological processes underlying aggregation, such as growth and breakage. We compared model predictions to experimental data to select appropriate kernel functions, and found that larger aggregates had a higher breakage rate, biomass was partitioned asymmetrically following a breakage event, and aggregates grew exponentially. Our model was then validated against several datasets with different initial aggregate size distributions and was able to quantitatively predict changes in total biomass and mean aggregate size, as well as actual size distributions. We proposed a breakage mechanism where a fraction of biomass was lost upon each breakage event, and demonstrated that even though smaller aggregates have been shown to produce more paclitaxel, an optimum breakage rate was predicted for maximum paclitaxel accumulation. We believe this is the first model to use a segregated, corpuscular approach to describe changes in the size distribution of plant cell aggregates, and represents an important first step in the design of rational strategies to control aggregation and optimize process performance. Copyright © 2011 Wiley Periodicals, Inc.

Immune competence in 90Sr-exposed, adult thymectomized and antilymphocyteglobulin-treated CBA mice. Pt. 1

International Nuclear Information System (INIS)

Bierke, P.

1989-01-01

CBA mice subjected to either adult thymectomy, internal exposure to 90 Sr or antilymphocyteglobulin treatment separately, or to combinations of the three were tested for cellular immune competence using their reaction to allogenic skin grafts. Peripheral blood white cell counts did not reveal any obvious correlation between the degree of mononuclear cell depletion and the ability to accept grafts, suggesting that the particular treatments depleted specific fractions of mononuclear cells, differing in their extent of involvement in the rejection process. No single treatment alone induced a significant prolongation in the time elapsed before graft rejection. Adult thymectomy followed by appropriate antilymphocyteglobulin treatment induced severe lymphocytopenia and a profound suppression of the cell-mediate immune system, as evidenced by the acceptance of allogenic skin grafts. When applied to 90 Sr-preexposed mice the same treatment induced lifelong acceptance of grafts, indicating a similar, though weaker immunosuppressive impact of 90 Sr. Hence it was possible to significantly enhance immunosuppression in 90 Sr-exposed mice. This in vivo model should be useful when investigating the role of immunological responsiveness in radiation carcinogenesis. (orig.)

[Treatment of Schatzker IV tibial plateau fractures with arthroscopy combined with MIPPO technique].

Science.gov (United States)

Li, Jian-Wen; Ye, Feng; Bi, Da-Wei; Zheng, Xiao-Dong; Chen, Jian-Liang

2018-02-25

To discusses the clinical effects of arthroscopy combined with minimally invasive percutaneous plate osteosynthesis(MIPPO) technology in treating Schatzker IV tibial plateau fractures. From January 2012 to January 2016, 19 patients with Schatzker type IV tibial plateau fractures were treated with arthroscopy combined with minimally invasive technique including 12 males and 7 females with an average age of 46.5 years old ranging from 19 to 78 years old. Patients were suffering knee pain, swelling, flexion and extension limited, and other symptoms preoperative. Patients were followed up and assessed by Rasmussen knee function score. No infection, traumatic arthritis, and knee joint valgus occurred after operation. Nineteen cases were followed up for 12 to 24 months with an average of 18.6 months. Fracture healing time was 3 to 5 months with an average of 3.8 months. The knee pain and limited mobility improved significantly. The range of autonomic movement of joints was from 90 to 136 degrees. According to Rasmussen functional score criteria, the total score was 27.00±2.49, the result was excellent in 16 cases, good in 2 cases, fair in 1 case. Arthroscopic treatment for Schatzker type IV tibial plateau fractures combined with MIPPO can simultaneously treat internal structural injuries such as meniscus and other knee joints, with less trauma, fewer complications, and faster joint function recovery, but we must strictly grasp surgical indications and avoid expanding injuries. Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.

Electrical properties of resistive switches based on Ba1-χSrχTiO3 thin films prepared by RF co-sputtering

International Nuclear Information System (INIS)

Marquez H, A.; Hernandez R, E.; Zapata T, M.; Guillen R, J.; Cruz, M. P.; Calzadilla A, O.; Melendez L, M.

2010-01-01

In this work, was proposed the use of Ba 1-χ Sr χ TiO 3 (0≤x≤1) thin films for the construction of metal-insulator-metal heterostructures; and their great potential for the development of non-volatile resistance memories (ReRAM) is shown. The deposition of Ba 1-χ Sr χ TiO 3 thin films was done by the RF co-sputtering technique using two magnetron sputtering cathodes with BaTiO 3 and SrTiO 3 targets. The chemical composition (x parameter) in the deposited Ba 1-χ Sr χ TiO 3 thin films was varied through the RF powder applied to the targets. The constructed metal-insulator-metal heterostructures were Al/Ba 1-χ Sr χ TiO 3 /nichrome. The I-V measurements of the heterostructures showed that their hysteretic characteristics change depending on the Ba/Sr ratio of the Ba 1-χ Sr χ TiO 3 thin films; the Ba/Sr ratio was determined by employing the energy dispersive spectroscopy; Sem micrographs showed that Ba 1-χ Sr χ TiO 3 thin films were uniform without cracks or pinholes. Additionally, the analysis of the X-ray diffraction results indicated the substitutional incorporation of Sr into the BaTiO 3 lattice and the obtainment of crystalline films for the entire range of the x values. (Author)

Experimental autoabsorption curve 90Sr in SrCO3. Efficiency calculation to detection of 90Sr, 90Y and 90Sr + 90Y in a beta gas proportional counter

International Nuclear Information System (INIS)

Gasco, C.; Alvarez, A.

1987-01-01

Strontium-90 has been determined by radiochemical separation techniques in environmental samples. These techniques, of course, cannot separate the two strontium radionuclides from each other of from stable strontium. Consequently the end product of the chemical separation contains all strontium isotopes in SrCO 3 . The beta particules emitted by 90 Sr are absorbed by the SrCO 3 precipitate. This is the main source of error in the activity measurement. It has been prepared sources of 90 Sr in SrCO 3 in order to determinate the counting efficiency and autoabsorption curve. Also detection efficiencies have been calibrated using known activities of 90 Y and equilibrium mixture of 90 Sr+ 90 Y in the same geometry than our samples. The activity of 90 Sr by ingrowth of 90 Y has been calculated by our computer program. (author). 2 figs., 3 refs

Charge Ordering, Competing Magnetic Interactions, and Magneto-Resistance Effects in Layered Iron(IV)-Based Oxides

International Nuclear Information System (INIS)

Adler, P.; Ghosh, S.

2002-01-01

Iron(IV)-based Ruddlesden-Popper-type oxides Sr 3 Fe 2-x Co x O 7-y (0≤x≤1) have been synthesized and studied by various techniques. It is shown that iron-57 Moessbauer spectroscopy is a powerful tool for elucidating the intimate correlations between chemical composition, electron-transport properties, electronic state, magnetism, and the large magneto-resistance effects in this system.

Isotope ratio 87Sr/86Sr in limestones from Bambui group, Brazil (MG)

International Nuclear Information System (INIS)

Kawashita, K.; Mizusaki, A.M.P.; Kiang, C.H.

1987-01-01

The Sr composition of ancient seawater can be estimated from the analysis of carbonate rocks and, in some cases, used to estimate the age of the analyzed carbonate. The normalized 87Sr/86Sr ratios in calcium carbonate fractions from 14 core samples in the Bambui Group near Montalvania, MG, were found to range between .7077 and .7280. The higher values are attributable to Sr isotopic exchange between silicate and carbonate phases during diagenesis. The ratio of .7077 obtained in two pure calcium carbonate samples is here suggested as the best aproximation for the 87Sr/86Sr value for the Bambui sea. This ratio is compatible with an age of about 700 Ma., estimated from the published 87Sr/86Sr curve of Veizer and others, an age in accordance with Quadros recent (1987, in preparation) identification of marine acritarchs from the latest Precambrian (Vendian). (author) [pt

Structural and compositional characterization of synthetic (Ca,Sr)-tremolite and (Ca,Sr)-diopside solid solutions

Science.gov (United States)

Gottschalk, M.; Najorka, J.; Andrut, M.

Tremolite (CaxSr1-x)2Mg5[Si8O22/(OH)2] and diopside (CaxSr1-x)Mg[Si2O6] solid solutions have been synthesized hydrothermally in equilibrium with a 1 molar (Ca,Sr)Cl2 aqueous solution at 750°C and 200 MPa. The solid run products have been investigated by optical, electron scanning and high resolution transmission electron microscopy, electron microprobe, X-ray-powder diffraction and Fourier-transform infrared spectroscopy. The synthesized (Ca,Sr)-tremolites are up to 2000 µm long and 30 µm wide, the (Ca,Sr)-diopsides are up to 150 µm long and 20 µm wide. In most runs the tremolites and diopsides are well ordered and chain multiplicity faults are rare. Nearly pure Sr-tremolite (tr0.02Sr-tr0.98) and Sr-diopside (di0.01Sr-di0.99) have been synthesized. A continuous solid solution series, i.e. complete substitution of Sr2+ for Ca2+ on M4-sites exists for (Ca,Sr)-tremolite. Total substitution of Sr2+ for Ca2+ on M2-sites can be assumed for (Ca,Sr)-diopsides. For (Ca,Sr)-tremolites the lattice parameters a, b and β are linear functions of composition and increase with Sr-content whereas c is constant. For the diopside series all 4 lattice parameters are a linear function of composition; a, b, c increase and β decreases with rising Sr-content. The unit cell volume for tremolite increases 3.47% from 906.68 Å3 for tremolite to 938.21 Å3 for Sr-tremolite. For diopside the unit cell volume increases 4.87 % from 439.91 Å3 for diopside to 461.30 Å3 for Sr-diopside. The observed splitting of the OH stretching band in tremolite is caused by different configurations of the next nearest neighbors (multi mode behavior). Resolved single bands can be attributed to the following configurations on the M4-sites: SrSr, SrCa, CaCa and CaMg. The peak positions of these 4 absorption bands are a linear function of composition. They are shifted to lower wavenumbers with increasing Sr-content. No absorption band due to the SrMg configuration on the M4-site is observed. This indicates

Development of {sup 90}Sr-{sup 90}Y generators; Desenvolvimento de geradores de {sup 90}Sr-{sup 90}Y

Energy Technology Data Exchange (ETDEWEB)

Barrio, Graciela, E-mail: gracielabarrio@gmail.co [Pontificia Univ. Catolica de Sao Paulo (PUC-SP), SP (Brazil). Dept. de Fisica; Osso Junior, Joao Alberto, E-mail: jaossoj@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2007-07-01

Yttrium-90 is a radioisotope of great interest in the field of Nuclear Medicine. It is considered one of the most important and most used radionuclides for radioimmunotherapeutical applications, especially promising for the treatment of certain types of cancer. Another important application of {sup 90}Y is radio synovectomy. This radionuclide has a half-life of 64 hours, emits long range beta particles (maximum energy of 2.3 MeV) and decays, without intermediate nuclides, to a stable daughter. {sup 90}Y may be obtained carrier-free, generated by the decay of its parent {sup 90}Sr (half-life=28 years). {sup 90}Sr is a product from uranium fission, and due to its long half-life, can be indefinitely used, which is certainly advantageous. It is present in great amounts, and needs to be processed and purified in order to be used as raw material for the generators. Generators of {sup 90}Sr-{sup 90}Y may thus be used during various months, due to {sup 90}Sr long half-life. Several methods for the separation of {sup 90}Y from {sup 90}Sr by solvent extraction and ion exchange have been reported in literature. Thanks to its simplicity, ion exchange techniques have been more commonly used for this generator system. The main objective of this work was to develop a methodology for the preparation of {sup 90}Sr-{sup 90}Y generators, using cationic exchange resins. In such method, {sup 90}Sr is strongly adsorbed in the resin and {sup 90}Y is eluted by a 0.003 M EDTA solution. According to the quality control carried out, results showed that elution yields are greater than 65%, thus confirming the efficiency of the separation method used.

Optimization of Process Parameters of Extraction of Amentoflavone, Quercetin and Ginkgetin from Taxus chinensis Using Supercritical CO2 Plus Co-Solvent

Directory of Open Access Journals (Sweden)

Xiao Ruan

2014-10-01

Full Text Available The effects of extraction time, temperature, pressure and different concentration of ethanol and their interactions on the yields of amentoflavone, quercetin and ginkgetin extracted from Taxus chinensis by supercritical CO2 were investigated by using a central composite design (CCD. An CCD experimental design with four factors and five levels was used to optimize the extraction parameters. Ultra performance liquid chromatography (UPLC was used to analyze the content of the tree components in the extracts. Experimental results show that the main effects of factors and their interactions are significant on the yields (p < 0.05. The optimal extraction conditions were established for the three compounds: yield of 4.47 mg/g for amentoflavone at 48 °C, 25 MPa, 2.02 h and 78.5% ethanol, 3.73 mg/g for quercetin at 46 °C, 24 MPa, 2.3 h, 82% ethanol and 3.47 mg/g for ginkgetin at 48 °C, 20 MPa, 2.38 h, 82% ethanol, respectively.

Sequential separation of cs, ca and ba for 90sr assessment

International Nuclear Information System (INIS)

Dianu, M.; Bucur, C.

2015-01-01

A two-steps chemical treatment technique for strontium assessment from aqueous samples is described in this paper. The method was applied to simulated samples containing stable elements of Ni, Cs, Ca, Ba, Mn, Fe, Co and Eu. The transition elements (Ni, Mn, Fe, Co, Eu) were precipitated as hydroxides, followed by alkaline-earth metals separation (Ca, Ba) as carbonates. Finally, the Sr was purified by extraction chromatography using Triskem International Sr resin. The strength of Sr sorption in nitric acid increases with increasing acid concentration, and the optimal bonding strength is achieved in 8 M HNO3. The combination of successive precipitations with extraction chromatography for complete removal of other interferences from Sr matrix leads to good recovery and decontamination factor values. (authors)

Effect of Wood Aging on Wine Mineral Composition and 87Sr/86Sr Isotopic Ratio.

Science.gov (United States)

Kaya, Ayse D; Bruno de Sousa, Raúl; Curvelo-Garcia, António S; Ricardo-da-Silva, Jorge M; Catarino, Sofia

2017-06-14

The evolution of mineral composition and wine strontium isotopic ratio 87 Sr/ 86 Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and 87 Sr/ 86 Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect 87 Sr/ 86 Sr, not precluding the use of this parameter for wine traceability purposes.

Aflibercept and FOLFOX6 Treatment for Previously Untreated Stage IV Colorectal Cancer

Science.gov (United States)

2018-04-03

Mucinous Adenocarcinoma of the Colon; Mucinous Adenocarcinoma of the Rectum; Signet Ring Adenocarcinoma of the Colon; Signet Ring Adenocarcinoma of the Rectum; Stage IV Colon Cancer; Stage IV Rectal Cancer

Geochronological synthesis of Bahia state and the crustal evolution, based in evolution diagram of Sr and initial rate of Sr87/Sr86

International Nuclear Information System (INIS)

Sato, K.

1986-01-01

The crustal evolution of the ancient terrains of the State of Bahia, Brazil, is attempted with the aid of Sr isotopic results as natural tracers. Some Nd and Pb isotopic data are also available, and support the main conclusions based on Sr evolution diagrams. The analysis of the Sr evolution diagrams shows that the Archean Terrains are mainly formed by accretion from mantle-derived material, but crustal reworking is indicated by the high initial 87 Sr/ 86 Sr value of the Jequie Complex. The Transamazonian mobile belt include both types of materials, but the 87 Sr/ 86 Sr value, generally lower than those of the Jequie Complex, markes improbable a direct derivation. During Middle and Late Proterozoic, the continental crust was already well consolidated, and reworking of crustal material predominated within the Espinhaco and Brasiliano folded systems [pt

A new approach to treatment of resistant gram-positive infections: potential impact of targeted IV to oral switch on length of stay

Directory of Open Access Journals (Sweden)

Trust Sarah

2006-06-01

Full Text Available Abstract Background Patients prescribed intravenous (IV glycopeptides usually remain in hospital until completion of this treatment. Some of these patients could be discharged earlier if a switch to an oral antibiotic was made. This study was designed to identify the percentage of inpatients currently prescribed IV glycopeptides who could be discharged earlier if a switch to an oral agent was used, and to estimate the number of bed days that could be saved. We also aimed to identify the patient group(s most likely to benefit, and to estimate the number of days of IV therapy that could be prevented in patients who remained in hospital. Methods Patients were included if they were prescribed an IV glycopeptide for 5 days or more. Predetermined IV to oral antibiotic switch criteria and discharge criteria were applied. A multiple logistic regression model was used to identify the characteristics of the patients most likely to be suitable for earlier discharge. Results Of 211 patients, 62 (29% could have had a reduced length of stay if they were treated with a suitable oral antibiotic. This would have saved a total of 649 inpatient days (median 5 per patient; range 1–54. A further 31 patients (15% could have switched to oral therapy as an inpatient thus avoiding IV line use. The patients most likely to be suitable for early discharge were those with skin and soft tissue infection, under the cardiology, cardiothoracic surgery, orthopaedics, general medical, plastic surgery and vascular specialities, with no high risk comorbidity and less than five other regularly prescribed drugs. Conclusion The need for glycopeptide therapy has a significant impact on length of stay. Effective targeting of oral antimicrobials could reduce the need for IV access, allow outpatient treatment and thus reduce the length of stay in patients with infections caused by antibiotic resistant gram-positive bacteria.

Fast neutron boost for the treatment of grade IV astrocytomas

International Nuclear Information System (INIS)

Breteau, N.; Destembert, B.; Favre, A.; Pheline, C.; Schlienger, M.

1989-01-01

A previous study, on grade IV astrocytomas, compared a combination of photons and fast neutron boost to photons only, both treatments being delivered following a concentrated irradiation schedule. A slight improvement in survival was observed after neutron boost for non operated patients, but not for operated patients. Since death was always related to local recurrence and since no complication occurred after neutron boost, the neutron dose was increased from 6 to 7 Gy in January 1985. No improvement in survival was observed for patients treated with neutron boost after complete resection. After subtotal resection, the group that was treated with the higher neutron boost (7 Gy) showed a significant benefit in survival at twelve months. When patients had only a biopsy before irradiation, there was a benefit in survival after neutron boost, but no additional benefit was gained when the size of the neutron boost was increased from 6 to 7 Gy. (orig.) [de

Macrocyclic receptor showing extremely high Sr(II)/Ca(II) and Pb(II)/Ca(II) selectivities with potential application in chelation treatment of metal intoxication.

Science.gov (United States)

Ferreirós-Martínez, Raquel; Esteban-Gómez, David; Tóth, Éva; de Blas, Andrés; Platas-Iglesias, Carlos; Rodríguez-Blas, Teresa

2011-04-18

Herein we report a detailed investigation of the complexation properties of the macrocyclic decadentate receptor N,N'-Bis[(6-carboxy-2-pyridil)methyl]-4,13-diaza-18-crown-6 (H(2)bp18c6) toward different divalent metal ions [Zn(II), Cd(II), Pb(II), Sr(II), and Ca(II)] in aqueous solution. We have found that this ligand is especially suited for the complexation of large metal ions such as Sr(II) and Pb(II), which results in very high Pb(II)/Ca(II) and Pb(II)/Zn(II) selectivities (in fact, higher than those found for ligands widely used for the treatment of lead poisoning such as ethylenediaminetetraacetic acid (edta)), as well as in the highest Sr(II)/Ca(II) selectivity reported so far. These results have been rationalized on the basis of the structure of the complexes. X-ray crystal diffraction, (1)H and (13)C NMR spectroscopy, as well as theoretical calculations at the density functional theory (B3LYP) level have been performed. Our results indicate that for large metal ions such as Pb(II) and Sr(II) the most stable conformation is Δ(δλδ)(δλδ), while for Ca(II) our calculations predict the Δ(λδλ)(λδλ) form being the most stable one. The selectivity that bp18c6(2-) shows for Sr(II) over Ca(II) can be attributed to a better fit between the large Sr(II) ions and the relatively large crown fragment of the ligand. The X-ray crystal structure of the Pb(II) complex shows that the Δ(δλδ)(δλδ) conformation observed in solution is also maintained in the solid state. The Pb(II) ion is endocyclically coordinated, being directly bound to the 10 donor atoms of the ligand. The bond distances to the donor atoms of the pendant arms (2.55-2.60 Å) are substantially shorter than those between the metal ion and the donor atoms of the crown moiety (2.92-3.04 Å). This is a typical situation observed for the so-called hemidirected compounds, in which the Pb(II) lone pair is stereochemically active. The X-ray structures of the Zn(II) and Cd(II) complexes show that

Blood Mononuclear Cell Mitochondrial Respiratory Chain Complex IV Activity is Decreased in Multiple Sclerosis Patients: Effects of β-Interferon Treatment

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Iain Hargreaves

2018-02-01

Full Text Available Objectives: Evidence of mitochondrial respiratory chain (MRC dysfunction and oxidative stress has been implicated in the pathophysiology of multiple sclerosis (MS. However, at present, there is no reliable low invasive surrogate available to evaluate mitochondrial function in these patients. In view of the particular sensitivity of MRC complex IV to oxidative stress, the aim of this study was to assess blood mononuclear cell (BMNC MRC complex IV activity in MS patients and compare these results to age matched controls and MS patients on β-interferon treatment. Methods: Spectrophotometric enzyme assay was employed to measure MRC complex IV activity in blood mononuclear cell obtained multiple sclerosis patients and aged matched controls. Results: MRC Complex IV activity was found to be significantly decreased (p < 0.05 in MS patients (2.1 ± 0.8 k/nmol × 10−3; mean ± SD] when compared to the controls (7.2 ± 2.3 k/nmol × 10−3. Complex IV activity in MS patients on β-interferon (4.9 ± 1.5 k/nmol × 10−3 was not found to be significantly different from that of the controls. Conclusions: This study has indicated evidence of peripheral MRC complex IV deficiency in MS patients and has highlighted the potential utility of BMNCs as a potential means to evaluate mitochondrial function in this disorder. Furthermore, the reported improvement of complex IV activity may provide novel insights into the mode(s of action of β-interferon.

Results of field studies on 90SR and stable SR soil-to-plant transfer

International Nuclear Information System (INIS)

Gerzabek, M.H.; Artner, C.; Horak, O.; Mueck, K.

1992-01-01

In 1987 and 1988 at 35 sites plants ready to harvest and the corresponding soils (0 - 20 cm) were collected for 90 Sr and stable strontium analyses. Sample preparation and measurement led to a detection limit of 0.008 Bq 90 Sr kg -1 . The 90 Sr-contamination of Austrian soils ranged from 396 to 1998 Bq m -2 . Known from literature the contribution of the Chernobyl fallout amounted to app. 25 % of the total contamination. Stable strontium contents of the soils were between 6 and 62.5 mg kg -1 . Bariumtriethanolamine extracted 17.7 to 62.3 % of the total stable Sr in soil. 90 Sr-concentrations in cereal grains ranged from 0.03 to 0.67 Bq kg -1 (fresh wight) for maize and barley, respectively. The values for other foodstuff were between 0.15 (white cabbage) and 0.91 Bq kg -1 (spinach). Stable strontium contents were between 0.079 mg kg -1 (maize) and 72.5 mg kg -1 (celery shoot). The following mean 90 Sr soil-to-plant transfer factors for cereal grains were obtained: 0.010 (maize), 0.097 (rye), 0.049 (wheat), 0.095 (barley). Transfer factors for straw were up to 50 times higher (maize). The transfer of 90 Sr into vegetables and potatoes reached the same order of magnitude compared to the cereals. In all cases soil-to-plant transfer of stable Sr was clearly lower up to 60 % of the respective values for 90 Sr. Thus natural stable strontium is less plant available than 90 Sr. The influence of soil parameters on the 90 Sr transfer into plants was examinated by correlation analyses. Increasing exchangeable calcium contents of the soils resulted in a significant reduction of Sr soil-to-barley straw transfer. (authors)

Internal bremsstrahlung from 89Sr and 90Sr

International Nuclear Information System (INIS)

Sayibaba, T.; Narasimha Murity, K.; Rao, C.R.; Satyaprakash; Gubbi, G.K.

1987-01-01

The internal bremsstrahlung (IB) spectra emitted in the beta-decays of 89 Sr and 90 Sr were measured with a HPGe detector and a multichannel analyser along with a standard geometrical set-up. Sufficient care has been taken to avoid spurious effects. After making all the necessary corrections, the experimental results were compared with the corresponding theoretical distributions due to Knipp and Uhlenbeck and Bloch (KUB), Lewis and Ford, Nilsson, and also due to Ford and Martin (detour theory). The total IB yields of intensity and energy from each of the isotopes in the investigated energy regions are also determined and compared with the corresponding theoretical values. The present results of IB from 89 Sr are satisfactorily accounted for by the KUB theory. In the case of 90 Sr the experimental results of IB coincide with the Coulomb-corrected theoretical distibution due to Nilsson in the energy range from 60 keV to 110 keV and Beyond 110 keV, they are found to be in excess over Nilsson's theory as well as the detour theory due to Ford and Martin up to the maximum photon energy studied, namely 350 keV

Effect of Sr/Ti Ratio on the Photocatalytic Properties of SrTiO3

International Nuclear Information System (INIS)

Sulaeman, U; Yin, S; Sato, T

2011-01-01

Since strontium titanate is a wide gap semiconductor, it requires UV light to generate the photocatalytic activities. Modification of strontium titanate to show photocatalytic activity under visible light irradiation is the essential work to efficiently utilize the sun light energy for environmental application. It is expected that the synthesis of SrTiO 3 with variation of Sr/Ti atomic ratio could induce the defect crystals having unique photocatalytic properties. The SrTiO 3 with various Sr/Ti atomic ratios were synthesized by microwave-assisted solvothermal reaction of SrCl 2 .6H 2 O and Ti(OC 3 H 7 ) 4 in KOH aqueous solutions with different atomic ratios of Sr/Ti. The products were characterized by TG-DTA, XRD and DRS. The photocatalytic activity was determined by DeNO x ability using LED lamps with the wavelengths of 627 nm (red), 530 nm (green), 445 nm (blue) and 390 nm (UV). The nanoparticles of perovskite type SrTiO 3 with the particle size of 30-40 nm were successfully synthesized. The visible light responsive photocatalytic activity was generated by adding excess amount of Sr. The photocatalytic activity in visible light could be enhanced by an increase in the Sr/Ti atomic ratio up to 1.25, indicating that the visible light responsive photocatalytic activity is due to the generation of new band gap between the conduction band and valence band of SrTiO 3 by the formation of oxygen vacancy.

Radiative rates for E1, E2, M1, and M2 transitions in the Br-like ions Sr IV, Y V, Zr VI, Nb VII, and Mo VIII

International Nuclear Information System (INIS)

Aggarwal, Kanti M.; Keenan, Francis P.

2015-01-01

Energies and lifetimes are reported for the lowest 375 levels of five Br-like ions, namely Sr IV, Y V, Zr VI, Nb VII, and Mo VIII, mostly belonging to the 4s 2 4p 5 , 4s 2 4p 4 4ℓ, 4s4p 6 , 4s 2 4p 4 5ℓ, 4s 2 4p 3 4d 2 , 4s4p 5 4ℓ, and 4s4p 5 5ℓ configurations. Extensive configuration interaction has been included and the general-purpose relativistic atomic structure package (GRASP) has been adopted for the calculations. Additionally, radiative rates are listed among these levels for all E1, E2, M1, and M2 transitions. From a comparison with the measurements, the majority of our energy levels are assessed to be accurate to better than 2%, although discrepancies between theory and experiment for a few are up to 6%. An accuracy assessment of the calculated radiative rates (and lifetimes) is more difficult, because no prior results exist for these ions

Mechanosynthesis and mechanical activation processes to the preparation of the Sr2[Srn-1TinO3n+1] Ruddlesden-Popper family

International Nuclear Information System (INIS)

Hungria, Teresa; Hungria, A.-B.; Castro, Alicia

2004-01-01

A novel mechanochemical activation route has been applied in order to obtain the n=1-4 and ∞ members of the Sr 2 [Sr n-1 Ti n O 3n+1 ] Ruddlesden-Popper series. The evolution of the (n+1)SrO:nTiO 2 powder mixtures during mechanical treatment was followed by X-ray powder diffraction in all cases. Except for the 2SrO:TiO 2 composition, SrTiO 3 was always mechanosynthesized. High-energy milling of 2SrO:TiO 2 sample resulted in the formation of nanosized Sr 2 TiO 4 , which is the only K 2 NiF 4 -type oxide prepared by mechanical treatment until now. The mechanical treatment was followed by annealing at different temperatures to establish the optimized protocol for synthesis of each member of the series. SrTiO 3 , Sr 2 TiO 4 and Sr 3 Ti 2 O 7 were obtained with very important decreases in the formation temperatures and reaction times as compared with the traditional ceramic method. Final and milled products were studied by X-ray powder diffraction at room and increasing temperatures, and by thermal analysis and scanning and high resolution transmission electron microscopy

Sol-Gel Synthesis of La(0.6)Sr(0.4)CoO(3-x) and Sm(0.5)Sr(0.5)CoO(3-x) Cathode Nanopowders for Solid Oxide Fuel Cells

Science.gov (United States)

Bansal, Narottam P.; Wise, Brent

2011-01-01

Nanopowders of La(0.6)Sr(0.4)CoO(3-x) (LSC) and Sm(0.5)Sr(0.5)CoO(3-x) (SSC) compositions, which are being investigated as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFC) with La(Sr)Ga(Mg)O(3-x) (LSGM) as the electrolyte, were synthesized by low-temperature sol-gel method using metal nitrates and citric acid. Thermal decomposition of the citrate gels was followed by simultaneous DSC/TGA methods. Development of phases in the gels, on heat treatments at various temperatures, was monitored by x-ray diffraction. Solgel powders calcined at 550 to 1000 C consisted of a number of phases. Single perovskite phase La(0.6)Sr(0.4)CoO(3-x) or Sm(0.5)Sr(0.5)CoO(3-x) powders were obtained at 1200 and 1300 C, respectively. Morphological analysis of the powders calcined at various temperatures was done by scanning electron microscopy. The average particle size of the powders was approx.15 nm after 700 C calcinations and slowly increased to 70 to 100 nm after heat treatments at 1300 to 1400 C.

Early Intervention of Intravenous KB220IV- Neuroadaptagen Amino-Acid Therapy (NAAT)™ Improves Behavioral Outcomes in a Residential Addiction Treatment Program: A Pilot Study

Science.gov (United States)

Miller, Merlene; Chen, Amanda LC; Stokes, Stan D.; Silverman, Susan; Bowirrat, Abdalla; Manka, Matthew; Manka, Debra; Miller, David K.; Perrine, Kenneth; Chen, Thomas JH; Bailey, John A.; Downs, William; Waite, Roger L.; Madigan, Margaret A.; Braverman, Eric R.; Damle, Uma; Kerner, Mallory; Giordano, John; Morse, Siobhan; Oscar-Berman, Marlene; Barh, Debmalya; Blum, Kenneth

2014-01-01

Substance use disorders (SUD) are inheritable and the culprit is hypodopaminergic function regulated by reward genes. We evaluated a natural dopaminergic agonist; KB220 intravenous (IV) and oral variants, to improve dopaminergic function in SUD. Our pilot experiment found a significant reduction of chronic symptoms, measured by the Chronic Abstinence Symptom Severity (CASS) Scale. The combined group (IV and oral) did significantly better than the oral-only group over the first week and 30-day follow-up period. Next, the combination was given to129 subjects and three factors; Emotion, Somatic, and Impaired Cognition, with eigenvalues greater than one were extracted for baseline CASS-Revised (CASS-R) variables. Paired sample t-tests for pre and post-treatment scales showed significant declines (p = .00001) from pre- to post-treatment: t = 19.1 for Emotion, t = 16.1 for Somatic, and t = 14.9 for Impaired Cognition. In a two-year follow-up of 23 subjects who underwent KB220IV therapy (at least five IV treatments over seven days) plus orals for 30+ days: 21 (91%) were sober at six months, 19 (82%) having no relapse; 19 (82%) were sober at one year, 18 (78%) having no relapse; and 21 (91%) were sober two-years post-treatment, 16 (70%) having no relapse. We await additional research and advise caution in interpreting these encouraging results. PMID:23457891

Regional and interspecific variation in Sr, Ca, and Sr/Ca ratios in avian eggshells from the USA.

Science.gov (United States)

Mora, Miguel A; Brattin, Bryan; Baxter, Catherine; Rivers, James W

2011-08-01

To examine regional variation in strontium (Sr), which at high concentrations may reduce eggshell quality, increase egg breakage and reproductive failure, we analyzed Sr, and calcium (Ca) concentrations and Sr/Ca ratios in eggshells from 20 avian species from California, Texas, Idaho, Kansas, and Michigan. In addition, we included data previously reported from Arizona to expand the regional comparisons and to better establish patterns of Sr, and Sr/Ca ratios in bird species across the United States. We found Sr concentrations varied significantly among regions, among species, and among foraging guilds; this variability is strongly influenced by the Sr/Ca ratios in surface water from locations close to the region where the eggshells were collected. Sr concentrations and Sr/Ca ratios were significantly higher in bird eggshells from the Volta wildlife region in the San Joaquin Valley, California and in various locales from Arizona. Sr concentrations and Sr/Ca ratios in bird eggshells from other locations in the USA were lower than those detected in these two regions. Among foraging guilds, invertivores had the highest Sr concentrations and Sr/Ca ratios and carnivores had the lowest. In general, the Sr/Ca ratio increased strongly with increasing Sr concentrations (R(2) = 0.99, P eggshells suggesting that these values could be determined from Sr/Ca ratios in water. Eggshell thickness was poorly correlated with Sr (R(2) = 0.03) but had a significant and positive correlation with Ca and was more properly correlated by a quadratic equation (R(2) = 0.50, Thickness = 2.13 - 0.02Ca - 3.07 * 10(-5)Ca(2)). Our study provides further evidence that Sr accumulates significantly in the avian eggshell, in some regions at concentrations which could be of concern for potential negative effects on reproduction. We suggest that when assessing the effects of metals on avian reproduction in regions with high Sr deposits in rock and soil, Sr concentrations in the eggshell also should be

Efficacy of Icotinib treatment in patients with stage IIIb/IV non-small cell lung cancer.

Science.gov (United States)

Qin, Na; Yang, Xinjie; Zhang, Quan; Li, Xi; Zhang, Hui; Lv, Jialin; Wu, Yuhua; Wang, Jinghui; Zhang, Shucai

2014-05-01

To evaluate the efficacy and safety of Icotinib - an orally administered, highly potent selective inhibitor of epidermal growth factor receptor (EGFR) and its active mutations, in the treatment of patients with advanced non-small cell lung cancer (NSCLC). A total of 101 patients with stage IIIb/IV NSCLC were treated with 125 mg Icotinib three times a day until disease progression or intolerable toxicity. Response rate was evaluated using response evaluation criteria in solid tumors and progression-free survival (PFS) was collected. The overall response rate (ORR) and disease control rate (DCR) were 37.6% (38/101) and 79.2% (80/101), respectively. The median PFS was 6.5 months. Multivariate analysis showed that female gender (P= 0.048, 95% confidence interval [CI] 1.010-6.016) and occurrence of rash (P= 0.002, 95% CI 1.667-9.809) were the independent predictive factors for ORR, while a performance status (PS) score of 0-1 (P= 0.001, 95% CI 0.024-0.402) and rash (P= 0.042, 95% CI 1.089-76.557) were the independent predictive factors for DCR. In addition, PS scores of 0-1 (P Icotinib were rash (35.6%) and diarrhea (17.8%), which was tolerable. Treatment of stage IIIb/IV NSCLC patients with Icotinib was effective and tolerable, specifically in patients with EGFR mutation.

Calcium-sensing receptor (CaSR): pharmacological properties and signaling pathways.

Science.gov (United States)

Conigrave, Arthur D; Ward, Donald T

2013-06-01

In this article we consider the mechanisms by which the calcium-sensing receptor (CaSR) induces its cellular responses via the control (activation or inhibition) of signaling pathways. We consider key features of CaSR-mediated signaling including its control of the heterotrimeric G-proteins Gq/11, Gi/o and G12/13 and the downstream consequences recognizing that very few CaSR-mediated cell phenomena have been fully described. We also consider the manner in which the CaSR contributes to the formation of specific signaling scaffolds via peptide recognition sequences in its intracellular C-terminal along with the origins of its high level of cooperativity, particularly for Ca(2+)o, and its remarkable resistance to desensitization. We also consider the nature of the mechanisms by which the CaSR controls oscillatory and sustained Ca(2+)i mobilizing responses and inhibits or elevates cyclic adenosine monophosphate (cAMP) levels dependent on the cellular and signaling context. Finally, we consider the diversity of the receptor's ligands, ligand binding sites and broader compartment-dependent physiological roles leading to the identification of pronounced ligand-biased signaling for agonists including Sr(2+) and modulators including l-amino acids and the clinically effective calcimimetic cinacalcet. We note the implications of these findings for the development of new designer drugs that might target the CaSR in pathophysiological contexts beyond those established for the treatment of disorders of calcium metabolism. Copyright © 2013 Elsevier Ltd. All rights reserved.

Facile Synthesis of SrCO3-Sr(OH2/PPy Nanocomposite with Enhanced Photocatalytic Activity under Visible Light

Directory of Open Access Journals (Sweden)

Alfredo Márquez-Herrera

2016-01-01

Full Text Available Pyrrole monomer was chemically polymerized onto SrCO3-Sr(OH2 powders to obtain SrCO3-Sr(OH2/polypyrrole nanocomposite to be used as a candidate for photocatalytic degradation of methylene blue dye (MB. The material was characterized by Fourier transform infrared (FTIR spectroscopy, UV/Vis spectroscopy, and X-ray diffraction (XRD. It was observed from transmission electronic microscopy (TEM analysis that the reported synthesis route allows the production of SrCO3-Sr(OH2 nanoparticles with particle size below 100 nm which were embedded within a semiconducting polypyrrole matrix (PPy. The SrCO3-Sr(OH2 and SrCO3-Sr(OH2/PPy nanocomposites were tested in the photodegradation of MB dye under visible light irradiation. Also, the effects of MB dye initial concentration and the catalyst load on photodegradation efficiency were studied and discussed. Under the same conditions, the efficiency of photodegradation of MB employing the SrCO3-Sr(OH2/PPy nanocomposite increases as compared with that obtained employing the SrCO3-Sr(OH2 nanocomposite.

[Outcome of operative treatment for supination-external rotation Lauge-Hansen stage IV ankle fractures].

Science.gov (United States)

Kołodziej, Łukasz; Boczar, Tomasz; Bohatyrewicz, Andrzej; Zietek, Paweł

2010-01-01

Ankle fractures are among the most common musculoskeletal injures. These fractures occur with an overall age- and sex-adjusted incidence rate around 180 per 100 000 person-years. The most frequent mechanism is considered to be supination-external rotation (60 to 80% of all ankle fractures) consisting of pathologic external rotation of the foot initially placed in some degree of supination. According to Lauge-Hansen classification, ankle joint structures are damaged in a sequence where the final, stage IV injuries, represents transverse fracture of the medial malleolus or its equivalent-rupture of the deltoid ligament. The aim of this study is to compare the results of two subtypes of supination-external rotation stage IV fractures. 43 patients treated surgically in 2006 to 2007 at Authors institution because of stage IV supination-external rotation ankle fracture were submitted to retrospective analysis. There were 25 patients with bimalleolar fracture (type 1) and in 18 patients with lateral malleolar fracture with accompanying rupture of the deltoid ligament (type 2). The mean age was 46 years (from 20 to 82 years). Average follow up period was 37 months (from 24 to 46 months). For the evaluation of treatment AOFAS hind-foot score (American Orthopedic Foot and Ankle Society) was used. The mean AOFAS score scale for Type 1 fractures was 85 points and for type 2 was significantly higher and amounted to 91 points (p ankle fractures with medial malleolar fracture, requires the implementation of additional diagnostic and therapeutic strategies and procedures in order to improve the outcome of results.

Hydrothermal synthesis and characterization of Si and Sr co-substituted hydroxyapatite nanowires using strontium containing calcium silicate as precursors

International Nuclear Information System (INIS)

Zhang, Na; Zhai, Dong; Chen, Lei; Zou, Zhaoyong; Lin, Kaili; Chang, Jiang

2014-01-01

In the absence of any organic surfactants and solvents, the silicon (Si) and strontium (Sr) co-substituted hydroxyapatite [Ca 10 (PO 4 ) 6 (OH) 2 , Si/Sr-HAp] nanowires were synthesized via hydrothermal treatment of the Sr-containing calcium silicate (Sr-CS) powders as the precursors in trisodium phosphate (Na 3 PO 4 ) aqueous solution. The morphology, phase, chemical compositions, lattice constants and the degradability of the products were characterized. The Si/Sr-HAp nanowires with diameter of about 60 nm and up to 2 μm in length were obtained after hydrothermal treatment of the Sr-CS precursors. The Sr and Si substitution amount of the HAp nanowires could be well regulated by facile tailoring the Sr substitution level of the precursors and the reaction ratio of the precursor/solution, respectively. The SiO 4 tetrahedra and Sr 2+ ions occupied the crystal sites of the HAp, and the lattice constants increased apparently with the increase of the substitution amount. EDS mapping also suggested the uniform distribution of Si and Sr in the synthetic nanowires. Moreover, the Si/Sr-substitution apparently improved the degradability of the HAp materials. Our study suggested that the precursor transformation method provided a facile approach to synthesize the Si/Sr co-substituted HAp nanowires with controllable substitution amount, and the synthetic Si/Sr-HAp nanowires might be used as bioactive materials for hard tissue regeneration applications. - Highlights: • Si/Sr-HAp nanowires were hydrothermally transformed from Sr x -CaSiO 3 precursors. • The Si/Sr-substitution level could be facilely regulated. • The nanowire-like morphology and composition could be simultaneously regulated

The selective removal of 90Sr and 137Cs from liquid low-level waste at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Bostick, D.T.; Arnold, W.D.; Burgess, M.W.; Taylor, P.A.; Kent, T.E.

1995-01-01

Methods are being developed for the selective removal of the two principal radioactive contaminants, 90 Sr and 137 Cs, from liquid low-level waste generated and/or stored at Oak Ridge National Laboratory. These methods are to be used in a future centralized treatment facility at ORNL. Removal of 90 Sr in the proposed treatment flashed is based on coprecipitation from strongly alkaline waste by adding stable strontium to the waste solution. Ferric sulfate, added with the stable strontium, improves the 90 Sr removal and aids in the flocculation of the strontium carbonate (SrCO 3 ) precipitate. After separation of the solids, the resultant supernate is adjusted to pH 8 for the cesium removal treatment. Upon pH adjustment, aluminum originally present in the untreated alkaline waste precipitates and sorbs an additional amount of 90 Sr. Cesium is removed from the neutralized waste by two sequential treatments with potassium cobalt hexacyanoferrate (KCCF) slurry formed by the addition of potassium ferrocyanide (K 4 Fe(CN) 6 ) and cobalt nitrate (Co(NO 3 ) 2 ) solutions. The cumulative decontamination factors (DFs) for 90 Sr and 137 Cs in benchscale studies are 4900 and 1 x 10 6 , respectively, if high speed centrifugation is used for the liquid/solid separations. Efforts are now underway to evaluate process-scale techniques to perform the liquid/solid separations required for removal of SrCO 3 and 137 Cs-bearing hexacyanoferrate solids from the treated waste solution

Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

Energy Technology Data Exchange (ETDEWEB)

Aina, Valentina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Bergandi, Loredana, E-mail: loredana.bergandi@unito.it [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy); Lusvardi, Gigliola; Malavasi, Gianluca [Department of Chemical and Geological Sciences, Università di Modena and Reggio Emilia, Via Campi 183, 41125 Modena (Italy); Imrie, Flora E.; Gibson, Iain R. [School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD (United Kingdom); Cerrato, Giuseppina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Ghigo, Dario [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy)

2013-04-01

A series of Sr-substituted hydroxyapatites (HA), of general formula Ca{sub (10−x)}Sr{sub x}(PO{sub 4}){sub 6}(OH){sub 2}, where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl{sub 2,} in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in

Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

International Nuclear Information System (INIS)

Aina, Valentina; Bergandi, Loredana; Lusvardi, Gigliola; Malavasi, Gianluca; Imrie, Flora E.; Gibson, Iain R.; Cerrato, Giuseppina; Ghigo, Dario

2013-01-01

A series of Sr-substituted hydroxyapatites (HA), of general formula Ca (10−x) Sr x (PO 4 ) 6 (OH) 2 , where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl 2, in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in HA has a positive effect

Coral Sr-U Thermometry

Science.gov (United States)

DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

2016-12-01

Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, we present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

Solar Thermochemical Energy Storage Through Carbonation Cycles of SrCO3/SrO Supported on SrZrO3.

Science.gov (United States)

Rhodes, Nathan R; Barde, Amey; Randhir, Kelvin; Li, Like; Hahn, David W; Mei, Renwei; Klausner, James F; AuYeung, Nick

2015-11-01

Solar thermochemical energy storage has enormous potential for enabling cost-effective concentrated solar power (CSP). A thermochemical storage system based on a SrO/SrCO3 carbonation cycle offers the ability to store and release high temperature (≈1200 °C) heat. The energy density of SrCO3/SrO systems supported by zirconia-based sintering inhibitors was investigated for 15 cycles of exothermic carbonation at 1150 °C followed by decomposition at 1235 °C. A sample with 40 wt % of SrO supported by yttria-stabilized zirconia (YSZ) shows good energy storage stability at 1450 MJ m(-3) over fifteen cycles at the same cycling temperatures. After further testing over 45 cycles, a decrease in energy storage capacity to 1260 MJ m(-3) is observed during the final cycle. The decrease is due to slowing carbonation kinetics, and the original value of energy density may be obtained by lengthening the carbonation steps. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hepatic imaging in stage IV-S neuroblastoma

International Nuclear Information System (INIS)

Franken, E.A. Jr.; Smith, W.L.; Iowa Univ., Iowa City; Cohen, M.D.; Kisker, C.T.; Platz, C.E.

1986-01-01

Stage IV-S neuroblastoma describes a group of infants with tumor spread limited to liver, skin, or bone marrow. Such patients, who constitute about 25% of affected infants with neuroblastoma, may expect spontaneous tumor remission. We report 18 infants with Stage IV-S neuroblastoma, 83% of whom had liver involvement. Imaging investigations included Technetium 99m sulfur colloid scan, ultrasound, and CT. Two patterns of liver metastasis were noted: ill-defined nodules or diffuse tumor throughout the liver. Distinction of normal and abnormal liver with diffuse type metastasis could be quite difficult, particularly with liver scans. We conclude that patients with Stage IV-S neuroblastoma have ultrasound or CT examination as an initial workup, with nuclear medicine scans reserved for followup studies. (orig.)

Biosynthesis of Silver Nanoparticles Using Taxus yunnanensis Callus and Their Antibacterial Activity and Cytotoxicity in Human Cancer Cells

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Qian Hua Xia

2016-09-01

Full Text Available Plant constituents could act as chelating/reducing or capping agents for synthesis of silver nanoparticles (AgNPs. The green synthesis of AgNPs has been considered as an environmental friendly and cost-effective alternative to other fabrication methods. The present work described the biosynthesis of AgNPs using callus extracts from Taxus yunnanensis and evaluated their antibacterial activities in vitro and potential cytotoxicity in cancer cells. Callus extracts were able to reduce silver nitrate at 1 mM in 10 min. Transmission electron microscope (TEM indicated the synthesized AgNPs were spherical with the size range from 6.4 to 27.2 nm. X-ray diffraction (XRD confirmed the AgNPs were in the form of nanocrystals. Fourier transform infrared spectroscopy (FTIR suggested phytochemicals in callus extracts were possible reducing and capping agents. The AgNPs exhibited effective inhibitory activity against all tested human pathogen bacteria and the inhibition against Gram-positive bacteria was stronger than that of Gram-negative bacteria. Furthermore, they exhibited stronger cytotoxic activity against human hepatoma SMMC-7721 cells and induced noticeable apoptosis in SMMC-7721 cells, but showed lower cytotoxic against normal human liver cells (HL-7702. Our results suggested that biosynthesized AgNPs could be an alternative measure in the field of antibacterial and anticancer therapeutics.

Calcilytic Ameliorates Abnormalities of Mutant Calcium-Sensing Receptor (CaSR) Knock-In Mice Mimicking Autosomal Dominant Hypocalcemia (ADH).

Science.gov (United States)

Dong, Bingzi; Endo, Itsuro; Ohnishi, Yukiyo; Kondo, Takeshi; Hasegawa, Tomoka; Amizuka, Norio; Kiyonari, Hiroshi; Shioi, Go; Abe, Masahiro; Fukumoto, Seiji; Matsumoto, Toshio

2015-11-01

Activating mutations of calcium-sensing receptor (CaSR) cause autosomal dominant hypocalcemia (ADH). ADH patients develop hypocalcemia, hyperphosphatemia, and hypercalciuria, similar to the clinical features of hypoparathyroidism. The current treatment of ADH is similar to the other forms of hypoparathyroidism, using active vitamin D3 or parathyroid hormone (PTH). However, these treatments aggravate hypercalciuria and renal calcification. Thus, new therapeutic strategies for ADH are needed. Calcilytics are allosteric antagonists of CaSR, and may be effective for the treatment of ADH caused by activating mutations of CaSR. In order to examine the effect of calcilytic JTT-305/MK-5442 on CaSR harboring activating mutations in the extracellular and transmembrane domains in vitro, we first transfected a mutated CaSR gene into HEK cells. JTT-305/MK-5442 suppressed the hypersensitivity to extracellular Ca(2+) of HEK cells transfected with the CaSR gene with activating mutations in the extracellular and transmembrane domains. We then selected two activating mutations locating in the extracellular (C129S) and transmembrane (A843E) domains, and generated two strains of CaSR knock-in mice to build an ADH mouse model. Both mutant mice mimicked almost all the clinical features of human ADH. JTT-305/MK-5442 treatment in vivo increased urinary cAMP excretion, improved serum and urinary calcium and phosphate levels by stimulating endogenous PTH secretion, and prevented renal calcification. In contrast, PTH(1-34) treatment normalized serum calcium and phosphate but could not reduce hypercalciuria or renal calcification. CaSR knock-in mice exhibited low bone turnover due to the deficiency of PTH, and JTT-305/MK-5442 as well as PTH(1-34) increased bone turnover and bone mineral density (BMD) in these mice. These results demonstrate that calcilytics can reverse almost all the phenotypes of ADH including hypercalciuria and renal calcification, and suggest that calcilytics can become a

Magnetism in the p-type Monolayer II-VI semiconductors SrS and SrSe

Science.gov (United States)

Lin, Heng-Fu; Lau, Woon-Ming; Zhao, Jijun

2017-01-01

Using density functional theory calculations, we study the electronic and magnetic properties of the p-type monolayer II-VI semiconductors SrX (X = S,Se). The pristine SrS and SrSe monolayers are large band gap semiconductor with a very flat band in the top valence band. Upon injecting hole uniformly, ferromagnetism emerges in those system in a large range of hole density. By varying hole density, the systems also show complicated phases transition among nonmagnetic semiconductor, half metal, magnetic semiconductor, and nonmagnetic metal. Furthermore, after introducing p-type dopants in SrS and SrSe via substitutionary inserting P (or As) dopants at the S (or Se) sites, local magnetic moments are formed around the substitutional sites. The local magnetic moments are stable with the ferromagnetic order with appreciable Curie temperature. The ferromagnetism originates from the instability of the electronic states in SrS and SrSe with the large density of states at the valence band edge, which demonstrates a useful strategy for realizing the ferromagnetism in the two dimensional semiconductors. PMID:28378761

Measurement of 90Sr radioactivity in a rapid method of strontium estimation by solvent extraction with dicarbollides

International Nuclear Information System (INIS)

Svoboda, K.; Kyrs, M.

1994-01-01

The application of liquid scintillation counting to the measurement of 90 Sr radioactivity was studied, using a previously published rapid method of strontium separation, based on solvent extraction with a solution of cobalt dicarbollide and Slovafol 909 in a nitrobenzene-carbon tetrachloride mixture and subsequent stripping of strontium with a 0.15 M Chelaton IV (CDTA) solution at pH 10.2. With liquid scintillation counting, a more efficient elimination of the effect of 90 Y β-activity on 90 Sr counting is possible than when measuring the evaporated aliquot with the use of a solid scintillator. The adverse effect of traces of dicarbollide, nitrobenzene, and CCl 4 passed over in the aqueous 90 Sr solution prepared for counting, is caused by the (poorly reproducible) shift of the 90 Sr + 90 Y β-radiation spectral curve towards lower energies, the so-called quenching. The shift is independent of the aqueous phase concentration of the organic compounds mentioned. They can be removed by shaking the aqueous reextract with an equal volume of octanol or amyl acetate so that the undesirable spectral shift does not occur. No loss of strontium was found in this washing procedure. (author) 2 tabs., 6 figs., 5 refs

Electronic parameters of Sr2M2O7 (M = V, Nb, Ta) and Sr-O chemical bonding

DEFF Research Database (Denmark)

Atuchin, Victor V.; Grivel, Jean-Claude; Zhang, Zhaoming

2010-01-01

XPS measurements were carried out on Sr2Nb2O7 and Sr2Ta2O7 powder samples, which were synthesized using standard solid state method. The binding energy differences between the O 1s and cation core level, Δ(O-Sr) = BE(O 1s) - BE(Sr 3d5/2), was used to characterize the valence electron transfer...... on the formation of the Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and Sr2Ta2O7 and the previously published structural and XPS data for other Sr-oxide compounds. A new empirical relationship between Δ(O-Sr) and L(Sr-O) was obtained. Possible applications...

Systematic variations of 87Sr/56Sr ratios, Sr compositions, selected major-oxide concentrations, and mineral abundances in piston cores from the Red Sea

International Nuclear Information System (INIS)

Boger, P.D.; Boger, J.L.; Faure, G.

1980-01-01

A mixing model is presented which relates the concentrations of Sr to the 87 Sr/ 86 Sr ratios and concentrations of other elements contained in a mixture of two components. The model is applied to the measured 87 Sr/ 86 Sr ratios, Sr, CaO, Fe 2 O 3 and SiO 2 concentrations of the detrital fractions of sediment from three piston cores representing different depositional environments in the Red Sea. The sediment is shown to be a mixture of two components derived from old sialic rocks and young volcanic rocks of the surrounding land masses. One of the cores contained a third component which is identified as authigenic Fe 2 O 3 . Removal of this contaminant is shown to return the system to its original detrital constituents. (Auth.)

Dynamic models of reduced order of main components of a M SR

International Nuclear Information System (INIS)

Garcia B, F. B.; Morales S, J. B.; Polo L, M. A.; Espinosa P, G.

2011-11-01

The reactors of melted salts called Molten Salt Fast Reactor (MSFR), have seen a resurgence of interest in the last decade. This design is one of the six proposed for the IV generation reactors. The most active development was in the middle of 1950 and principles of 1970 in the Oak Ridge National Laboratories (ORNL). In this work the mathematician modeling of the main components in the primary and secondary circuits of a M SR is presented. In particular the dynamics of the heat exchanger is analyzed and they are considered several materials to optimize the system thermodynamically. (Author)

Addition to the analysis of the Sr VI and Sr VII spectra

International Nuclear Information System (INIS)

Wyart, J.F.

1989-01-01

Fifty-six lines of multicharged strontium are measured with an improved wavelength accuracy, or interpreted for the first time. They are 4p-4s, 4p-5s and 4p-4d transitions in Sr VII and 4p-5s transitions in Sr VI. The revision of the singlet-triplet connection in Sr VII is supported by theoretical survey of the ground configuration in Ge-like ions. (orig.)

The role of Sr2+ on the structure and reactivity of SrO-CaO-ZnO-SiO2 ionomer glasses.

Science.gov (United States)

Boyd, Daniel; Towler, Mark R; Watts, Sally; Hill, Robert G; Wren, Anthony W; Clarkin, Owen M

2008-02-01

The suitability of Glass Polyalkenoate Cements (GPCs) for use in orthopaedics is retarded by the presence in the glass phase of aluminium, a neurotoxin. Unfortunately, the aluminium ion plays an integral role in the setting process of GPCs and its absence is likely to hinder cement formation. However, the authors have previously shown that aluminium free GPCs may be formulated based on calcium zinc silicate glasses and these novel materials exhibit significant potential as hard tissue biomaterials. To further improve their potential, and given that Strontium (Sr) based drugs have had success in the treatment of osteoporosis, the authors have substituted Calcium (Ca) with Sr in the glass phase of a series of aluminium free GPCs. However to date little data exists on the effect SrO has on the structure and reactivity of SrO-CaO-ZnO-SiO(2) glasses. The objective of this work was to characterise the effect of the Ca/Sr substitution on the structure of such glasses, and evaluate the subsequent reactivity of these glasses with an aqueous solution of Polyacrylic acid (PAA). To this end (29)Si MAS-NMR, differential scanning calorimetry (DSC), X-ray diffraction, and network connectivity calculations, were used to characterize the structure of four strontium calcium zinc silicate glasses. Following glass characterization, GPCs were produced from each glass using a 40 wt% solution of PAA (powder:liquid = 2:1.5). The working times and setting times of the GPCs were recorded as per International standard ISO9917. The results acquired as part of this research indicate that the substitution of Ca for Sr in the glasses examined did not appear to significantly affect the structure of the glasses investigated. However it was noted that increasing the amount of Ca substituted for Sr did result in a concomitant increase in setting times, a feature that may be attributable to the higher basicity of SrO over CaO.

Measurement of Ce(IV) Concentration in Foam Decontaminant containing Fluorosurfactant

Energy Technology Data Exchange (ETDEWEB)

Jung, Chong Hun; Yang, H. B.; Yoon, I. H.; Choi, W. K.; Moon, J. K. [KAERI, Daejeon (Korea, Republic of); Lee, J. S. [Gachon University, Seongnam (Korea, Republic of)

2016-05-15

To improve the stability of the foam, surfactants and inorganic materials such as nanoparticles can be added. A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing the cerium (III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can be decomposed immediately. A concentration analysis of Ce(IV) in foam decontaminant containing a surfactant is necessary prior to the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment. A UV spectrometric method using the absorbance or potentiometric method with a potential difference in Ce(III)/Ce(IV), or a potentiometric titration method using Fe (II), can be used for a Ce(IV) concentration analysis. A UV spectrometric method has a problem receiving the influence of the surfactant, and a potentiometric method is difficult to use because of the problem of an insignificant change in the potential difference value of the Ce(III)/Ce(IV). Thus, the present study was undertaken to determine whether the potentiometric titration method can be used for an analysis of the Ce(IV) concentration in the nanoparticle-based foam decontaminant containing surfactant. It will be effectively used for the Ce(IV) concentration measurement, in relation to the subsequent research on the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment.

Thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments

Energy Technology Data Exchange (ETDEWEB)

Rai, Dhanpat; Roa, Linfeng; Weger, H.T.; Felmy, A.R. [Battelle, Pacific Northwest National Laboratory (PNNL) (United States); Choppin, G.R. [Florida State University (United States); Yui, Mikazu [Waste Isolation Research Division, Tokai Works, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

1999-01-01

This report provides thermodynamic data for predicting concentrations of Th(IV), U(IV), Np(IV), and Pu(IV) in geologic environments, and contributes to an integration of the JNC chemical thermodynamic database, JNC-TDB (previously PNC-TDB), for the performance analysis of geological isolation system for high-level radioactive wastes. Thermodynamic data for the formation of complexes or compounds with hydroxide, chloride, fluoride, carbonate, nitrate, sulfate and phosphate are discussed in this report. Where data for specific actinide(IV) species was lacking, the data were selected based on chemical analogy to other tetravalent actinides. In this study, the Pitzer ion-interaction model is used to extrapolate thermodynamic constants to zero ionic strength at 25degC. (author)

Determination of Sr-90 in milk samples from the study of statistical results

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Otero-Pazos Alberto

2017-01-01

Full Text Available The determination of 90Sr in milk samples is the main objective of radiation monitoring laboratories because of its environmental importance. In this paper the concentration of activity of 39 milk samples was obtained through radiochemical separation based on selective retention of Sr in a cationic resin (Dowex 50WX8, 50-100 mesh and subsequent determination by a low-level proportional gas counter. The results were checked by performing the measurement of the Sr concentration by using the flame atomic absorption spectroscopy technique, to finally obtain the mass of 90Sr. From the data obtained a statistical treatment was performed using linear regressions. A reliable estimate of the mass of 90Sr was obtained based on the gravimetric technique, and secondly, the counts per minute of the third measurement in the 90Sr and 90Y equilibrium, without having to perform the analysis. These estimates have been verified with 19 milk samples, obtaining overlapping results. The novelty of the manuscript is the possibility of determining the concentration of 90Sr in milk samples, without the need to perform the third measurement in the equilibrium.

Structures of the two new compounds distrontium copper(II) triselenite(IV) and distrontium copper(II) bis[hydrogenselenite(IV)] bisselenite(IV)

International Nuclear Information System (INIS)

Effenberger, H.

1988-01-01

Sr 2 Cu(SeO 3 ) 3 , M r =619.68, triclinic, Panti 1, a=7.229(3), b=7.710(3), c=8.656(3) A, α=102.68(3), β=105.31(3), γ=96.12(3) 0 , V=447.0 A 3 , Z=2, D x =4.60 Mg m -3 , λ(MoKα)=0.71073 A, μ=26.0 mm -1 , F(000)=558, room temperature, R=0.033 for 3330 reflections up to 2θ=70 0 . Sr 2 Cu(SeO 2 OH) 2 (SeO 3 ) 2 , M r =748.65, triclinic, Panti 1, a=5.260(1), b=6.961(1), c=9.052(2) A, α=67.86(1), β=75.40(1), γ=80.41(1) 0 , V=296.6A 3 , Z=1, D x =4.19 Mg m -3 , λ(MoKα)=0.71073 A, μ=22.6 mm -1 , F(000)=339, room temperature, R=0.036 for 2362 reflections up to 2θ=70 0 . In the two compounds the Sr atoms are [8] and [9] coordinated (Sr-O=2.52 to 2.93 A), the Cu atoms have a tetragonal-pyramidal [4+1] and a square-planar [4] coordination, respectively. The distance Se-O h (1.80 A) is significantly longer than the other Se-O bonds (1.66 to 1.73 A). In Sr 2 Cu(SeO 3 ) 3 , the SrO 8 polyhedra form a three-dimensional network; in Sr 2 Cu(SeO 2 OH) 2 (SeO 3 ) 2 , the SrO 9 polyhedra are edge-linked to form sheets which are connected by CuO 4 squares, SeO 3 groups and the hydrogen bond (O-H...O=2.88 A). (orig.)

Anorthite glass: a potential host matrix for 90Sr pencil

International Nuclear Information System (INIS)

Sengupta, Pranesh; Dey, G.K.; Fanara, Sara; Chakraborty, Sumit; Mishra, R.K.; Kaushik, C.P.

2011-01-01

With rising global concerns over health hazards, environmental pollution and possible malicious applications of radioactive materials, there is an increasing consciousness among public and Governmental agencies for its better control, accounting and security. Investigations carried out by International Atomic Energy Agency and other monitoring bodies reveal that among various radioactive materials, the easily dispersible ones are high activity sealed sources (generally called radioactive pencils) used for various peaceful applications. Ideally, these sealed sources should be safely secured within specialized facilities, but in practice, it is not always done. Hence, there is a need to take an extra precautionary measure to ensure that the matrices currently used for hosting the radionuclides within sealed sources are durable enough under harsh service conditions and situations arising due to possible mishaps (accidents, misplaced, stolen etc). Among the variety of useful radionuclides, 90 Sr is one which is regularly used to (i) combat bone cancer, (ii) destroy unwanted tissue on the surface of eye/skin, (iii) light up/provide energy to remotely accessible areas etc. However, due to its (i) toxicity, (ii) mobility, (iii) easy incorporation within human body, (iv) considerable half-life (∼ 29 years), (v) emission of beta (β - ) particles along with high energy gamma ( γ)-rays, and (vi) retention of significant toxicity within sources even after service life, release of 90 Sr poses a serious threat to the biosphere. Hence, there is a need to ensure that existing 90 Sr host matrices are capable of withstanding all sorts of adversity that may arise during service and under storage/disposal

About the structure and stability of complex carbonates of thorium (IV), cerium (IV), zirconium (IV), hafnium (IV)

International Nuclear Information System (INIS)

Dervin, Jacqueline

1972-01-01

This research thesis addressed the study of complex carbonates of cations of metals belonging to the IV A column, i.e. thorium (IV), zirconium (IV), hafnium (IV), and also cerium (IV) and uranium (VI), and more particularly focused on ionic compounds formed in solution, and also on the influence of concentration and nature of cations on stability and nature of the formed solid. The author first presents methods used in this study, discusses their precision and scope of validity. She reports the study of the formation of different complex ions which have been highlighted in solution, and the determination of their formation constants. She reports the preparation and study of the stability domain of solid complexes. The next part reports the use of thermogravimetric analysis, IR spectrometry, and crystallography for the structural study of these compounds

Input of 87Sr/86Sr ratios and Sr geochemical signatures to update knowledge on thermal and mineral waters flow paths in fractured rocks (N-Portugal)

International Nuclear Information System (INIS)

Marques, J.M.; Carreira, P.M.; Goff, F.; Eggenkamp, H.G.M.; Antunes da Silva, M.

2012-01-01

Strontium isotopes and other geochemical signatures are used to determine the relationships between CO 2 -rich thermal (Chaves: 76 °C) and mineral (Vilarelho da Raia, Vidago and Pedras Salgadas: 17 °C) waters discharging along one of the major NNE–SSW trending faults in the northern part of mainland Portugal. The regional geology consists of Hercynian granites (syn-tectonic-310 Ma and post-tectonic-290 Ma) intruding Silurian metasediments (quartzites, phyllites and carbonaceous slates). Thermal and mineral waters have 87 Sr/ 86 Sr isotopic ratios between 0.716713 and 0.728035. 87 Sr/ 86 Sr vs. 1/Sr define three end-members (Vilarelho da Raia/Chaves, Vidago and Pedras Salgadas thermal and mineral waters) trending from rainfall composition towards that of the CO 2 -rich thermal and mineral waters, indicating different underground flow paths. Local granitic rocks have 87 Sr/ 86 Sr ratios of 0.735697–0.789683. There is no indication that equilibrium was reached between the CO 2 -rich thermal and mineral waters and the granitic rocks. The mean 87 Sr/ 86 Sr ratio of the thermal and mineral waters (0.722419) is similar to the Sr isotopic ratios of the plagioclases of the granitic rocks (0.71261–0.72087). The spatial distribution of Sr isotope and geochemical signatures of waters and the host rocks suggests that the thermal and mineral waters circulate in similar but not the same hydrogeological system. Results from this study could be used to evaluate the applicability of this isotope approach in other hydrogeologic investigations.

A high 87Sr 86Sr mantle source for low alkali tholeiite, northern Great Basin

Science.gov (United States)

Mark, R.K.; Lee, Hu C.; Bowman, H.R.; Asaro, F.; McKee, E.H.; Coats, R.R.

1975-01-01

Olivine tholeiites, the youngest Tertiary units (about 8-11 m.y. old) at five widely spaced localities in northeastern Nevada, are geologically related to the basalts of the Snake River Plain, Idaho, to the north and are similar in major element and alkali chemistry to mid-ocean ridge basalts (MORB) and island arc tholeiites. The measured K (1250-3350 ppm), Rb (1??9-6??2 ppm) and Sr (140-240 ppm) concentrations overlap the range reported for MORB. Three of the five samples have low, unfractionated rare earth element (REE) patterns, the other two show moderate light-REE enrichment. Barium concentration is high and variable (100-780 ppm) and does not correlate with the other LIL elements. The rocks have 87Sr/86Sr = 0??7052-0??7076, considerably higher than MORB (~0??702-0??703). These samples are chemically distinct (i.e. less alkalic) from the olivine tholeiites from the adjacent Snake River Plain, but their Sr isotopic compositions are similar. They contain Sr that is distinctly more radiogenic than the basalts from the adjacent Great Basin. About 10 b.y. would be required for the mean measured Rb/Sr (~ 0??02) of these samples to generate, in a closed system, the radiogenic Sr they contain. The low alkali content of these basalts makes crustal contamination an unlikely mechanism. If the magma is uncontaminated, the time-averaged Rb/Sr of the source material must have been ~0??04. A significant decrease in Rb/Sr of the source material (a factor 2??) thus most probably occurred in the relatively recent (1??09 yr) past. Such a decrease of Rb/Sr in the mantle could accompany alkali depletion produced by an episode of partial melting and magma extraction. In contrast, low 87Sr 86Sr ratios indicate that the source material of the mid-ocean ridge basalts may have been depleted early in the Earth's history. ?? 1975.

Fabrication of Schottky Junction Between Au and SrTiO3

Science.gov (United States)

Inoue, Akira; Izumisawa, Kei; Uwe, Hiromoto

2001-05-01

A Schottky junction with a high rectification ratio between Au and La-doped SrTiO3 has been fabricated using a simple surface treatment. Highly La-doped (5%) SrTiO3 single crystals are annealed in O2 atmosphere at about 1000°C for 1 h and etched in HNO3 for more than five min. The HNO3 etching is performed in a globe box containing N2 to prevent pollution from the air. After the treatment, Au is deposited on the SrTiO3 surface in a vacuum (˜ 10-7 Torr) with an e-gun evaporator. The current voltage characteristics of the junction have shown excellent rectification properties, although junctions using neither annealed nor etched SrTiO3 exhibit high leak current in reverse voltage. The rectification ratio of the junction at 1 V is more than six orders of magnitude and there is no hysteresis in the current voltage spectra. The logarithm of the current is linear with the forward bias voltage. The ideal factor of the junction is estimated to be about 1.68. These results suggest that, if prevented from being pollution by the air, a good Schottky junction can be obtained by easy processes such as annealing in oxygen atmosphere and surface etching with acid.

SR-BI: Linking Cholesterol and Lipoprotein Metabolism with Breast and Prostate Cancer

Directory of Open Access Journals (Sweden)

Jorge L. Gutierrez-Pajares

2016-10-01

Full Text Available Studies have demonstrated the significant role of cholesterol and lipoprotein metabolism in the progression of cancer. The SCARB1 gene encodes the scavenger receptor class B type I (SR-BI, which is an 82-kDa glycoprotein with two transmembrane domains separated by a large extracellular loop. SR-BI plays an important role in the regulation of cholesterol exchange between cells and high-density lipoproteins. Accordingly, hepatic SR-BI has been shown to play an essential role in the regulation of the reverse cholesterol transport pathway, which promotes the removal and excretion of excess body cholesterol. In the context of atherosclerosis, SR-BI has been implicated in the regulation of intracellular signaling, lipid accumulation, foam cell formation, and cellular apoptosis. Furthermore, since lipid metabolism is a relevant target for cancer treatment, recent studies have focused on examining the role of SR-BI in this pathology. While signaling pathways have initially been explored in non-tumoral cells, studies with cancer cells have now demonstrated SR-BI’s function in tumor progression. In this review, we will discuss the role of SR-BI during tumor development and malignant progression. In addition, we will provide insights into the transcriptional and post-transcriptional regulation of the SCARB1 gene. Overall, studying the role of SR-BI in tumor development and progression should allow us to gain useful information for the development of new therapeutic strategies.

Use of inorganic ion exchange materials for the treatment of liquid waste

International Nuclear Information System (INIS)

El-Naggar, I.M.; Zakaria, E.S.; El-Absy, M.A.; Abdel-Hamid, M.M.; Abo-Mesalam, M.M.; Shady, S.A.; Abdelwahab, M.A.; Aly, H.F.

1997-01-01

To examine the ion exchange behaviour of the double salts of polybasic acid with tetravalent metals type such as cerium(IV) and tin(IV) antimonates, different samples were prepared, heated at different temperatures and exposed to γ-irradiation. These samples were subject to X-ray, infra-red and thermal analysis. The exchange properties of the studied materials improved on increasing the Sb, Ce or Sn molar ratios and the drying temperature. The rate of the isotopic exchange was controlled by particle diffusion for the metal ions studied and was faster as the heating temperature was increased but slower for materials with a higher exchange capacity. The physical thermodynamic parameters have been evaluated which give some information regarding the mechanism of ion exchange on the surface of inorganic materials. The removal of radioactive isotopes of Na + , Cs + , Sr 2+ , Co 2+ and Eu 3+ was carried out by in-situ precipitation or by using preformed precipitate of tin(IV) and cerium(IV) antimonates. The products of in-situ precipitations act as ion exchange materials with high chemical and radioactive stabilities. The new materials have relatively high capacity compared with CeSb and SnSb. The irradiated cerium(IV) antimonate has been successfully used for the quantitative separation of cesium which suggests its use in the treatment of active liquid waste. (author). 24 refs, 7 figs, 17 tabs

Synthesis, structural and dielectric properties of SrBi2- x La x Nb2O9 ceramics prepared by hydrothermal treatment

Science.gov (United States)

Afqir, Mohamed; Tachafine, Amina; Fasquelle, Didier; Elaatmani, Mohamed; Carru, Jean-Claude; Zegzouti, Abdelouahad; Daoud, Mohamed

2018-01-01

SrBi2- x La x Nb2O9 ( x = 0.2, 0.4 and 0.6) Aurivillius materials were prepared by hydrothermal treatment. The powder prepared by this method is highly pure and not agglomerated. The morphology of the samples was characterized by SEM. The dielectric properties of all the compositions were investigated in the temperature range from 25 °C to 500 °C and in the frequency range between 100 Hz and 1 MHz. The dielectric properties at room temperature of the proposed materials can match up with La-doped SrBi2Nb2O9 ceramics prepared via the solid-state reaction method. Partial substitution of bismuth by lanthanum greatly affects the ferroelectric-paraelectric transition temperature, as the ferroelectric-paraelectric phase transition becomes diffuse and the Curie temperature shifts toward lower temperatures typically from 375 to 290 °C. The conductivity results obtained for the samples are explained taking into account the metal-binding energies.

Radionuclide X-ray fluorescence determination of Mn, Fe, Cu, Zn and Pb in wastewaters and sludges from wastewater treatment plants in Bratislava (SR)

International Nuclear Information System (INIS)

Harangozo, M.; Toelgyessy, J.

1997-01-01

Radiometric X-ray fluorescence analysis was used for the determination of Mn, Fe, Cu, Zn and Pb in wastewater and sludges from three wastewater treatment plants in Bratislava (SR). Metals were determined in wastewaters after preconcentration by 8-hydroxyquinoline and in sludges by drying and pressing to pellets. 238 Pu and 109 Cd was used for excitation of fluorescence radiation. (author)

87Sr/86Sr isotope fingerprinting of Scottish and Icelandic migratory shorebirds

International Nuclear Information System (INIS)

Evans, Jane; Bullman, Rhys

2009-01-01

Biosphere Sr isotope composition data from Iceland and Scotland suggest that terrestrially feeding birds from these two countries will have significantly different 87 Sr/ 86 Sr isotope composition in their tissues. The aim of this study is to test if these differences can be measured within the bone and feather of migratory wading birds, who feed terrestrially as juveniles, thus providing a provenance tool for these birds. The study shows that birds can be distinguished on the basis of the Sr isotope composition of their bone. The field for Icelandic birds is defined by data from juvenile common redshank (Tringa totanus) and whimbrel (Numenius phaeopus) which give 0.7056 ± 0.0012, (2σ, n = 7). The majority of Scottish birds in this study are from coastal regions and have a signature close to that of seawater of 0.7095 ± 0.0006 (2σ, n = 9). The Sr ratios in the body tissue of these two populations of all Icelandic and Scottish adult and juvenile birds analysed are significantly different (p 87 Sr/ 86 Sr values as high as 0.7194 which reflect their non-marine diet. Icelandic redshank (Tringa totanus robusta) that have flown to Scotland and returned to Iceland show the effect of the Scottish contribution to their diet with elevated values of 0.7086 ± 0.0004, (2σ, n = 6). Redshank found in Scotland that cannot be classified on the basis biometric analysis are shown to be of Icelandic origin and analysis of the primary feathers from two birds demonstrates that isotope variation between feathers could be used to track changes in diet related to the timing of individual feather growth.

Transport of Sr 2+ and SrEDTA 2- in partially-saturated and heterogeneous sediments

Science.gov (United States)

Pace, M. N.; Mayes, M. A.; Jardine, P. M.; McKay, L. D.; Yin, X. L.; Mehlhorn, T. L.; Liu, Q.; Gürleyük, H.

2007-05-01

Strontium-90 has migrated deep into the unsaturated subsurface beneath leaking storage tanks in the Waste Management Areas (WMA) at the U.S. Department of Energy's (DOE) Hanford Reservation. Faster than expected transport of contaminants in the vadose zone is typically attributed to either physical hydrologic processes such as development of preferential flow pathways, or to geochemical processes such as the formation of stable, anionic complexes with organic chelates, e.g., ethylenediaminetetraacetic acid (EDTA). The goal of this paper is to determine whether hydrological processes in the Hanford sediments can influence the geochemistry of the system and hence control transport of Sr 2+ and SrEDTA 2-. The study used batch isotherms, saturated packed column experiments, and an unsaturated transport experiment in an undisturbed core. Isotherms and repacked column experiments suggested that the SrEDTA 2- complex was unstable in the presence of Hanford sediments, resulting in dissociation and transport of Sr 2+ as a divalent cation. A decrease in sorption with increasing solid:solution ratio for Sr 2+ and SrEDTA 2- suggested mineral dissolution resulted in competition for sorption sites and the formation of stable aqueous complexes. This was confirmed by detection of MgEDTA 2-, MnEDTA 2-, PbEDTA 2-, and unidentified Sr and Ca complexes. Displacement of Sr 2+ through a partially-saturated undisturbed core resulted in less retardation and more irreversible sorption than was observed in the saturated repacked columns, and model results suggested a significant reservoir (49%) of immobile water was present during transport through the heterogeneous layered sediments. The undisturbed core was subsequently disassembled along distinct bedding planes and subjected to sequential extractions. Strontium was unequally distributed between carbonates (49%), ion exchange sites (37%), and the oxide (14%) fraction. An inverse relationship between mass wetness and Sr suggested that

Laser and Light Treatments for Hair Reduction in Fitzpatrick Skin Types IV-VI: A Comprehensive Review of the Literature.

Science.gov (United States)

Fayne, Rachel A; Perper, Marina; Eber, Ariel E; Aldahan, Adam S; Nouri, Keyvan

2018-04-01

Unwanted facial and body hair presents as a common finding in many patients, such as females with hirsutism. With advances in laser and light technology, a clinically significant reduction in hair can be achieved in patients with light skin. However, in patients with darker skin, Fitzpatrick skin types (FST) IV-VI, the higher melanin content of the skin interferes with the proposed mechanism of laser-induced selective photothermolysis, which is to target the melanin in the hair follicle to cause permanent destruction of hair bulge stem cells. Many prospective and retrospective studies have been conducted with laser and light hair-removal devices, but most exclude patients with darkly pigmented skin, considering them a high-risk group for unwanted side effects, including pigmentation changes, blisters, and crust formation. We reviewed the published literature to obtain studies that focused on hair reduction for darker skin types. The existing literature for this patient population identifies longer wavelengths as a key element of the treatment protocol and indicates neodymium-doped yttrium aluminum garnet (Nd:YAG), diode, alexandrite, and ruby lasers as well as certain intense pulsed light sources for safe hair reduction with minimal side effects in patients with FST IV-VI, so long as energy settings and wavelengths are appropriate. Based on the findings in this review, safe and effective hair reduction for patients with FST IV-VI is achievable under proper treatment protocols and energy settings.

[Surgical treatment for talar neck fracture of Hawkins III, IV type with compression hollow screws combined with external fixator].

Science.gov (United States)

Wang, Xian-Xun; Wan, Chang-Tao; Yu, Li

2017-05-25

To investigate the clinical effects of compression hollow screws combined with external fixator in treating talar neck fracture of Hawkins III, IV type. From March 2010 to August 2014, 15 patients with talar neck fractures of Hawkins III, IV type were treated by open reduction and compression hollow screws fixation complicated with external fixator fixation. Including 9 males and 6 females, aged from 17 to 65 years old with an average of 37.5 years old. There were 9 cases of Hawkins III and 6 cases of Hawkins IV type. Postoperative radiographs and CT of ankle were used to evaluate the fracture healing and talar necrosis. The function of ankle and foot were evaluated by American Society of Ankle and Foot Surgery(AOFAS). All the patients were followed up for 8 to 55 months with an average of 23.5 months and all fractures got bone healing from 13 to 38 weeks with an average of (17.99±6.81) weeks. Traumatic arthritis occurred in 7 cases and talar necrosis in 6 cases (2 cases of type III and 4 cases of type IV) after operation. The average AOFAS score was 61.80±18.75, including excellent in 4 cases, good in 2 cases, fair in 4 cases and poor in 5 cases. Talar neck fracture with Hawkins III, IV type has large possibility to develop avascular necrosis. Hollow compression screw combined with external fixation may late weight-bearing for ankle and can sufficiently guarantee bone healing time, and achieve good results for the treatment of talar neck fracture.

Ehlers-Danlos syndrome type IV

Directory of Open Access Journals (Sweden)

Germain Dominique P

2007-07-01

Full Text Available Abstract Ehlers-Danlos syndrome type IV, the vascular type of Ehlers-Danlos syndromes (EDS, is an inherited connective tissue disorder defined by characteristic facial features (acrogeria in most patients, translucent skin with highly visible subcutaneous vessels on the trunk and lower back, easy bruising, and severe arterial, digestive and uterine complications, which are rarely, if at all, observed in the other forms of EDS. The estimated prevalence for all EDS varies between 1/10,000 and 1/25,000, EDS type IV representing approximately 5 to 10% of cases. The vascular complications may affect all anatomical areas, with a tendency toward arteries of large and medium diameter. Dissections of the vertebral arteries and the carotids in their extra- and intra-cranial segments (carotid-cavernous fistulae are typical. There is a high risk of recurrent colonic perforations. Pregnancy increases the likelihood of a uterine or vascular rupture. EDS type IV is inherited as an autosomal dominant trait that is caused by mutations in the COL3A1 gene coding for type III procollagen. Diagnosis is based on clinical signs, non-invasive imaging, and the identification of a mutation of the COL3A1 gene. In childhood, coagulation disorders and Silverman's syndrome are the main differential diagnoses; in adulthood, the differential diagnosis includes other Ehlers-Danlos syndromes, Marfan syndrome and Loeys-Dietz syndrome. Prenatal diagnosis can be considered in families where the mutation is known. Choriocentesis or amniocentesis, however, may entail risk for the pregnant woman. In the absence of specific treatment for EDS type IV, medical intervention should be focused on symptomatic treatment and prophylactic measures. Arterial, digestive or uterine complications require immediate hospitalisation, observation in an intensive care unit. Invasive imaging techniques are contraindicated. Conservative approach is usually recommended when caring for a vascular

Ehlers-Danlos syndrome type IV

Science.gov (United States)

Germain, Dominique P

2007-01-01

Ehlers-Danlos syndrome type IV, the vascular type of Ehlers-Danlos syndromes (EDS), is an inherited connective tissue disorder defined by characteristic facial features (acrogeria) in most patients, translucent skin with highly visible subcutaneous vessels on the trunk and lower back, easy bruising, and severe arterial, digestive and uterine complications, which are rarely, if at all, observed in the other forms of EDS. The estimated prevalence for all EDS varies between 1/10,000 and 1/25,000, EDS type IV representing approximately 5 to 10% of cases. The vascular complications may affect all anatomical areas, with a tendency toward arteries of large and medium diameter. Dissections of the vertebral arteries and the carotids in their extra- and intra-cranial segments (carotid-cavernous fistulae) are typical. There is a high risk of recurrent colonic perforations. Pregnancy increases the likelihood of a uterine or vascular rupture. EDS type IV is inherited as an autosomal dominant trait that is caused by mutations in the COL3A1 gene coding for type III procollagen. Diagnosis is based on clinical signs, non-invasive imaging, and the identification of a mutation of the COL3A1 gene. In childhood, coagulation disorders and Silverman's syndrome are the main differential diagnoses; in adulthood, the differential diagnosis includes other Ehlers-Danlos syndromes, Marfan syndrome and Loeys-Dietz syndrome. Prenatal diagnosis can be considered in families where the mutation is known. Choriocentesis or amniocentesis, however, may entail risk for the pregnant woman. In the absence of specific treatment for EDS type IV, medical intervention should be focused on symptomatic treatment and prophylactic measures. Arterial, digestive or uterine complications require immediate hospitalisation, observation in an intensive care unit. Invasive imaging techniques are contraindicated. Conservative approach is usually recommended when caring for a vascular complication in a patient suffering

Immobilization of radioactive strontium in contaminated soils by phosphate treatment

International Nuclear Information System (INIS)

Kim, K.H.; Ammons, J.T.

1990-01-01

The feasibility of in situ phosphate- and metal- (calcium, aluminum, and iron) solution treatment for 90 Sr immobilization was investigated. Batch and column experiments were performed to find optimum conditions for coprecipitation of 90 Sr with Ca-, Al-, and Fe-phosphate compounds in contaminated soils. Separate columns were packed with artificially 85 Sr-contaminated acid soil as well as 90 Sr-contaminated soil from the Oak Ridge Reservation. After metal-phosphate treatment, the columns were then leached successively with either tapwater or 0.001 M CaCl 2 solution. Most of the 85 Sr coprecipitated with the metal phosphate compounds. Immobilization of 85 Sr and 90 Sr was affected by such factors as solution pH, metal and phosphate concentration, metal-to-phosphate ratio, and soil characteristics. Equilibration time after treatments also affected 85 Sr immobilization. Many technology aspects still need to be investigated before field applications are feasible, but these experiments indicate that phosphate-based in situ immobilization should prevent groundwater contamination and will be useful as a treatment technology for 90 Sr-contaminated sites. 15 refs., 3 figs., 1 tab

Ag loading induced visible light photocatalytic activity for pervoskite SrTiO3 nanofibers

Science.gov (United States)

Wu, Yeqiu; He, Tao

2018-06-01

The synthesis and photocatalytic activities of Ag-SrTiO3 nanofibers were reported in this work. The fabricated Ag-SrTiO3 nanofibers were characterized by TG-DSC, XRD, IR, XPS, SEM, TEM, DRS and ESR techniques. The XRD and IR results show that Ag-SrTiO3 nanofibers have a perovskite structure after the heat treatment at 700 °C. The XPS result shows that Ag element exists as Ag0 in the fabricated Ag-SrTiO3 nanofibers. The SEM and TEM images indicate the obtaining of nanofibers with porous structure. The photocatalytic activity of Ag-SrTiO3 nanofibers was evaluated by degrading RhB and MB under visible light irradiation. The Ag-SrTiO3 nanofibers show excellent photocatalytic activity under visible light irradiation because of the surface plasmon resonance effect of Ag0. In the photocatalysis process of RhB and MB, lots of hydroxyl radicals were generated, which plays the key role in the decomposition of organic pollutants.

Effect of oxygen gas and annealing treatment for magnetically enhanced reactive ion etched (Ba0.65,Sr0.35)TiO3 thin films

International Nuclear Information System (INIS)

Zhang Baishun; Quan Zuci; Zhang Tianjin; Guo Tao; Mo Shaobo

2007-01-01

Sol-gel-derived (Ba 0.65 ,Sr 0.35 )TiO 3 (BST) thin films were etched in CF 4 /Ar and CF 4 /Ar/O 2 plasmas using magnetically enhanced reactive ion etching technology. Experimental results show that adding appropriate O 2 to CF 4 /Ar can better the etching effects of BST films for the increase of etching rate and decrease of etched residues. The maximum etching rate is 8.47 nm/min when CF 4 /Ar/O 2 gas-mixing ratio is equal to 9/36/5. X-ray photoelectron spectroscopy (XPS) data confirm accumulation of reaction products on the etched surface due to low volatility of reaction products such as Ba and Sr fluorides, and these residues could be removed by annealing treatment. The exact peak positions and chemical shifts of the interested elements were deduced by fitting XPS narrow-scan spectra with symmetrical Gaussian-Lorentzian product function for Ba 3d, Sr 3d, and O 1s peaks, meanwhile asymmetrical Gaussian-Lorentzian sum function was used to fit Ti 2p doublet to adjust the multiple splitting and/or shake-up process of transition-metal Ti cations. Compared to the unetched counterparts, the etched Ba 3d 5/2 , Ba 3d 3/2 , Sr 3d 5/2 , Sr 3d 3/2 , Ti 2p 3/2 , Ti 2p 1/2 , and O 1s peaks shift towards higher binding energy regions by amounts of 1.31, 1.30, 0.60, 0.79, 0.09, 0.46, and 0.50 eV, respectively. While the etched Ti 2p 3/2 and Ti 2p 1/2 peaks have small chemical shifts for two reasons. One is that Ti fluoride (TiF z ) is mostly removed from the etched surface because of its higher volatility in the process of thermal desorption. The other is that there is a shift compensation between TiF z and the etched BST matrix in which Ti 4+ cations are partially reduced to form Ti x+ (0 0.65 ,Sr 0.35 )Ti 0.97 O 2.86 , (Ba 0.70 ,Sr 0.30 )Ti 0.24 O 1.39 , and (Ba 0.68 ,Sr 0.32 )Ti 0.95 O 2.74 , and then the average valence of Ti cations is estimated to be +3.84, +3.25, and +3.66 with respect to the electroneutrality principle, respectively. It is inferred that electrical

Effect of Sr-P Interaction on the Microstructure and Tensile Properties of A413.0 Type Alloys

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A. M. Samuel

2016-01-01

Full Text Available The present study was performed on low magnesium A413.0 type alloys. The results show that strontium (Sr is mainly concentrated in the silicon particles. Overmodification occurs when Sr precipitates in the form of Al2SrSi2, which takes place over a wide range of temperatures. The first peak occurs following the precipitation of α-Al, the second peak is merged with the precipitation of eutectic silicon (Si, and the third peak is a posteutectic reaction. Introduction of phosphorus (P to Sr-modified alloys leads to the formation of (Al,P,Sr2O5 compound, which reduces the modification effectiveness of Sr. Therefore, in the presence of P, the amount of added Sr should exceed 200 ppm. For the same levels of P, the tensile parameters of well modified alloys (233 ppm Sr are relatively higher than those partially modified with Sr (about 60 ppm Sr containing the same amount of P. During solution heat treatment, coarsening of the eutectic Si particles occurs by the growth of some particles at the expense of the dissolution of the smaller ones, as well as by the collision of nearby particles.

Thermodynamic assessment of the Pb-Sr system

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Zhang H.

2017-01-01

Full Text Available The Pb-Sr system has been critically reviewed and modeled by means of the CALPHAD (CALculation of PHAse Diagrams approach. It contains seven stoichiometric compounds, i.e. SrPb3, Sr3Pb5, Sr2Pb3, SrPb, Sr5Pb4, Sr5Pb3 and Sr2Pb, in which the SrPb3 and Sr2Pb phases melt congruently, and the other five phases form via peritectic reactions. The enthalpies of formation for the intermetallic compounds at 0 K are provided by first-principles calculations. The liquid, fcc and bcc phases are modeled as substitutional solution phases. Both Redlich-Kister and exponential polynomials are used to describe the excess Gibbs energy of the liquid. Two sets of self-consistent thermodynamic parameters are obtained by considering reliable experimental data and the computed enthalpies of formation. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information is satisfactorily accounted for by the present thermodynamic description.

Influence of 90Sr, adult thymectomy and antilymphocyteglobulin on haematopoietic tissues and peripheral blood leucocytes in CBA mice

International Nuclear Information System (INIS)

Bierke, P.

1986-01-01

The role or long-time immune suppression in carcinogenesis induced by the long-lived internal emitter 90 Sr, is investigated in an ongoing study. The experimental design is based on the assumption that impaired immune responsiveness, by other means than 90 Sr, might increase the neoplastic response in exposed individuals, and thus reflect a protective function, if existing. Intercomparison is made of the tumour yield in mice exposed to different single doses of 90 Sr and simultaneously subjected or not to long-term immune suppression by adult thymectomy (ATx) and/or antilymphocyteglobulin (ALG) treatment. Information on the general condition and responsiveness of the immune system, in the respective models, during tumour expectancy time, is essential for a conclusive evaluation of the results. To meet theses demands the present paper reports on histopathologic alternations in immune organs and changes in white blood cell counts, induced by the different combinations of 90 Sr, ATx + ALG treatment. The results confirm the prediction, that ATx + ALG is an efficient and, with respect to the purpose of the study, suitable treatment for additive long-term depression of the immune system in 90 Sr irradiated mice, evidenced in particular by increased depletion of monomorphonuclear cells (MNC) in lymphoid organs and peripheral blood. Subsequent reports will deal with functional immune parameters. (orig.)

System of Sr(NO2)2-Sr(OH)2-H2O at 25 deg C

International Nuclear Information System (INIS)

Popova, T.B.; Berdyukova, V.A.; Khutsistova, F.M.

1990-01-01

Sr(NO 2 ) 2 -Sr(OH) 2 -H 2 O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO 2 ) 2 xSr(OH) 2 x8H 2 O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained

C, Sr and Sr isotopic composition on probable vendian- tommotian carbonate sequences in Nw Argentina

International Nuclear Information System (INIS)

Sial, A. N.; Ferreira, V.P; Toselli, A.J.; Acenolaza, F.G; Pimentel, M.M; Parada, M.A; Alonso, R.N

2001-01-01

C-isotope stratigraphy is one of the most powerfool tools in Precambrian chronostratigraphy, especially when sediments lack recognizable animal fossils. The δ 13 C secular variation curves for marine carbonates in the Neoproterozoic-Cambrian interval show strong positive-negative excursions, several of them interpreted as the stratigraphic position of ancient ice ages (Hoffman et al. 1998). The Sr isotope composition of the seawater for this age interval is characterized by a continuous increase of 87 Sr/ 86 Sr that is interrupted, several times, by sharp rises, which represent important changes in the Earth history (Montanez et al. 2000). Only limited data on the behavior of C and Sr isotopes in carbonates are available in South America. We examine here carbonate sequences from the Argentine Precordillera, San Juan province, and from other carbonate sequences in NW Argentina that could be, potentially, proxies for the Precambrian-Cambrian transition. We have studied their δ 13 C and 87 Sr/ 86 Sr chemostratigraphy and compare it to global C and Sr isotope secular variation curves for this time span. This study aims to improve the relatively coarse stratigraphic resolution provided only by the study of the fossil record in some of the carbonate successions under consideration (au)

Shewanella putrefaciens mtrB encodes an outer membrane protein required for Fe(III) and Mn(IV) reduction.

Science.gov (United States)

Beliaev, A S; Saffarini, D A

1998-12-01

Iron and manganese oxides or oxyhydroxides are abundant transition metals, and in aquatic environments they serve as terminal electron acceptors for a large number of bacterial species. The molecular mechanisms of anaerobic metal reduction, however, are not understood. Shewanella putrefaciens is a facultative anaerobe that uses Fe(III) and Mn(IV) as terminal electron acceptors during anaerobic respiration. Transposon mutagenesis was used to generate mutants of S. putrefaciens, and one such mutant, SR-21, was analyzed in detail. Growth and enzyme assays indicated that the mutation in SR-21 resulted in loss of Fe(III) and Mn(IV) reduction but did not affect its ability to reduce other electron acceptors used by the wild type. This deficiency was due to Tn5 inactivation of an open reading frame (ORF) designated mtrB. mtrB encodes a protein of 679 amino acids and contains a signal sequence characteristic of secreted proteins. Analysis of membrane fractions of the mutant, SR-21, and wild-type cells indicated that MtrB is located on the outer membrane of S. putrefaciens. A 5.2-kb DNA fragment that contains mtrB was isolated and completely sequenced. A second ORF, designated mtrA, was found directly upstream of mtrB. The two ORFs appear to be arranged in an operon. mtrA encodes a putative 10-heme c-type cytochrome of 333 amino acids. The N-terminal sequence of MtrA contains a potential signal sequence for secretion across the cell membrane. The amino acid sequence of MtrA exhibited 34% identity to NrfB from Escherichia coli, which is involved in formate-dependent nitrite reduction. To our knowledge, this is the first report of genes encoding proteins involved in metal reduction.

Crystallization and properties of Sr-Ba aluminosilicate glass-ceramic matrices

Science.gov (United States)

Bansal, Narottam P.; Hyatt, Mark J.; Drummond, Charles H., III

1991-01-01

Powders of roller quenched (Sr,Ba)O-Al2O3-2SiO2 glasses of various compositions were uniaxially pressed into bars and hot isostatically pressed at 1350 C for 4 hours or cold isostatically pressed and sintered at different temperatures between 800 to 1500 C for 10 or 20 hours. Densities, flexural strengths, and linear thermal expansion were measured for three compositions. The glass transition and crystallization temperatures were determined by Differential Scanning Calorimetry (DSC). The liquidus and crystallization temperature from the melt were measured using high temperature Differential Thermal Analysis (DTA). Crystalline phases formed on heat treatment of the glasses were identified by powder X ray diffraction. In Sr containing glasses, the monoclinic celsian phase always crystallized at temperatures above 1000 C. At lower temperatures, the hexagonal analog formed. The temperature for orthorhombic to hexagonal structural transformation increased monotonically with SrO content, from 327 C for BaO-Al2O3-2SiO2 to 758 C for SrO-Al2O3-2SiO2. These glass powders can be sintered to almost full densities and monoclinic celsian phase at a relatively low temperature of 1100 C.

Measurement of resonance integral of the 90Sr(n,γ)91Sr reaction

International Nuclear Information System (INIS)

Nakamura, Shoji; Furutaka, Kazuyoshi; Wada, Hiroaki; Katoh, Toshio; Harada, Hideo; Fujii, Toshiyuki; Yamana, Hajimu

2001-01-01

To obtain fundamental data for research on nuclear transmutation method of radioactive wastes, the resonance integral (I 0 ) of the 90 Sr(n,γ) 91 Sr reaction was measured with an activation method. (author)

Effectiveness of Sr-binders tested using an in vitro model

International Nuclear Information System (INIS)

Hansen, Hanne S.; Eikelman, Margrethe; Hove, Knut

2008-01-01

the pH was increased to pH 8, and subsequently the Sr-binding was elevated to 80%. The zeolite A(Na) bound between 80 and 95% of the Ca, while zeolite P bound between 60 and 75% of the Ca in the rumen liquid mixture at pH 7.3. For all treatments and binders the binding of Mg was less than 20%. We conclude that zeolite A(Na) has promising properties as a Sr binding agent in animals. The zeolite is very efficient in binding Sr in the rumen and the large intestine, while it is not likely to affect the absorption taking place in the small intestine. Because the zeolite A(Na) demonstrated high affinity also to Ca, further studies of the binding of other minerals are required before zeolite A(Na) should be taken into practical use. (author)

Medicinal plants in the treatment of cancer

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Nenad M. Zlatić

2015-07-01

Full Text Available The purpose of this paper is to present a review of highly developed medicinal usages of plants in the treatment of cancer. In the last decades, the cancer treatment has been included in this range of plant use, due to plant active substances. Active substances or secondary metabolites are generally known for their widespread application. When it comes to the cancer treatment, these substances affect the uncontrolled cell division. Therefore, the plants which are the source of these substances are proved to be irreplaceable in this field of medicine. This paper deals with some of the most significant plants well known for their multiple aspects of beneficial medicinal influence. The group of the plants described is comprised of the following species: Taxus brevifolia (Taxaceae, Catharanthus roseus (Apocynaceae, Podophyllum peltatum (Berberidaceae, Camptotheca accuminata (Cornaceae, and Cephalotaxus harringtonia (Cephalotaxaceae. The comprehensive description of the plants in this paper includes the morphological characteristics, the features and the representation of the molecular structures of active substances, the particular influence that these active substances have and the general importance of the substances as seen from the aspect of cancer treatment mostly with reference to the impacts on cell cycle.

Immune competence in /sup 90/Sr-exposed, adult thymectomized and antilymphocyteglobulin-treated CBA mice. Pt. 1. Allogenic skin graft reaction

Energy Technology Data Exchange (ETDEWEB)

Bierke, P.

1989-01-01

CBA mice subjected to either adult thymectomy, internal exposure to /sup 90/Sr or antilymphocyteglobulin treatment separately, or to combinations of the three were tested for cellular immune competence using their reaction to allogenic skin grafts. Peripheral blood white cell counts did not reveal any obvious correlation between the degree of mononuclear cell depletion and the ability to accept grafts, suggesting that the particular treatments depleted specific fractions of mononuclear cells, differing in their extent of involvement in the rejection process. No single treatment alone induced a significant prolongation in the time elapsed before graft rejection. Adult thymectomy followed by appropriate antilymphocyteglobulin treatment induced severe lymphocytopenia and a profound suppression of the cell-mediate immune system, as evidenced by the acceptance of allogenic skin grafts. When applied to /sup 90/Sr-preexposed mice the same treatment induced lifelong acceptance of grafts, indicating a similar, though weaker immunosuppressive impact of /sup 90/Sr. Hence it was possible to significantly enhance immunosuppression in /sup 90/Sr-exposed mice. This in vivo model should be useful when investigating the role of immunological responsiveness in radiation carcinogenesis. (orig.).

FEP report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

FEP report for the safety assessment SR-Site

International Nuclear Information System (INIS)

2010-12-01

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

Thermal infrared and microwave absorbing properties of SrTiO3/SrFe12O19/polyaniline nanocomposites

International Nuclear Information System (INIS)

Hosseini, Seyed Hossein; Zamani, Parisa; Mousavi, S.Y.

2015-01-01

Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO 3 /SrFe 12 O 19 /PANI exhibited electric and electromagnetic properties. • The SrTiO 3 /SrFe 12 O 19 /PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO 3 was synthesized as IR absorbent and core and then SrFe 12 O 19 as microwave absorbent was prepared on SrTiO 3 via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO 3 /SrFe 12 O 19 nanoparticles via in situ polymerization by multi core–shell structures (SrTiO 3 /SrFe 12 O 19 /PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the SrTiO 3 /SrFe 12 O 19 /PANI nanocomposites have good compatible

The hyperfractionation in the oropharynx carcinomas treatment: stages III and IV

International Nuclear Information System (INIS)

Pinto, L.H.J.

1990-01-01

From April 1986 until May 1989. 112 patients with stages III and IV oropharynx carcinomas were included in a protocol comparing the use of Hyperfractionation and Conventional Fractionation. The doses were 6600 rad in 33 fractions of 200 rad for the conventional fractionation and 7040 rad in 64 fractions, two fractions of 110 rad per day for the hyperfractionation. As of January 1990 an analysis was performed in 98 patients, with a median follow-up of 14 months. The probability of complete responses in the oropharynx was 74%, with 84% for the hyperfractionation and 64% for the conventional fractionation ( p < 0,05). Survival was improved in 42 months for those patients treated with hyperfractionation: 27% versus 8% (p < 0,05). In patients with lesions out of the base of the tongue and in those with Karnofsky performance status of 50%, 60% and 70%, survival was improved with the use of hyperfractionation (p = 0,02 and p 0,006 respectively. The study demonstrates the superiority of hyperfractionation over the classical fractionation in the treatment of patients with carcinoma of the oropharynx. (author)

Changes in local surface structure and Sr depletion in Fe-implanted SrTiO{sub 3} (001)

Energy Technology Data Exchange (ETDEWEB)

Lobacheva, O., E-mail: olobache@gmail.com [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Yiu, Y.M. [Department of Chemistry, Western University, London, ON N6A 5B7 (Canada); Chen, N. [Canadian Light Source, Saskatoon, SK S7N 0X4 (Canada); Sham, T.K.; Goncharova, L.V. [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Department of Chemistry, Western University, London, ON N6A 5B7 (Canada)

2017-01-30

Highlights: • Fe ion implantation of SrTiO{sub 3} and post-implantation results in formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase. • In Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase, Fe assumes Fe{sup 3+} oxidation state in the bulk and Fe{sup 2+} oxidation state in the near surface area. • FEFF9 calculations indicate that Fe ions can substitute both Ti and Sr sites. • Formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase is accompanied by Sr depletion in the near surface region. - Abstract: Local surface structure of single crystal strontium titanate SrTiO{sub 3} (001) samples implanted with Fe in the range of concentrations between 2 × 10{sup 14} to 2 × 10{sup 16} Fe/cm{sup 2} at 30 keV has been investigated. In order to facilitate Fe substitution (doping), implanted samples were annealed in oxygen at 350 °C. Sr depletion was observed from the near-surface layers impacted by the ion-implantation process, as revealed by Rutherford Backscattering Spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray Absorption Near Edge Spectroscopy (XANES), and Atomic Force Microscopy (AFM). Hydrocarbon contaminations on the surface may contribute to the mechanisms of Sr depletion, which have important implications for Sr(Ti{sub 1-x}Fe{sub x})O{sub 3-δ} materials in gas sensing applications.

Development of methodology for the preparation of 90Sr-90Y generators

International Nuclear Information System (INIS)

Barrio, Graciela; Osso, Joao A.

2008-01-01

Among the more attractive radionuclides for therapeutic applications is yttrium-90. Its relatively short half-life (64.0h), maximum beta energy (2.28 MeV) make it well suited for a variety of applications, ranging from the radiolabeling of antibodies for tumor therapy to the production of radiolabeled particles for the treatment of liver malignancies. Yttrium-90 results from the decay of strontium-90 (28y) and decays to a stable daughter ( 90 Zr) and has no γ-ray, what makes this nuclide very attractive for therapeutic applications. 90 Y is produced through a generator system, from the decay of 90 Sr. Before it can safely employed in clinical applications, the 90 Y must be made essentially free of 90 Sr, an isotope known to cause bone marrow suppression. The objective of this work is to develop 90 Sr- 90 Y generator using a cation exchange method resin. This method was the most effects for the separation of 90 Y and 90 Sr. 90 Sr is strongly adsorbed in the resin and 90 Y is eluted in 0.003M EDTA. The generator efficiency and radionuclide control results were also evaluated using 85 Sr (γ-ray emitter). The generator was developed, using AG 50WX8 exchange resin converted to the Na+ form and then conditioned with 0.003M EDTA solution (pH=4.8). The quality control showed that 90 Y had no 8 '5Sr impurities, inside the detection limits of the detector. The results presented here are very promising, showing that the methodology is able to separate the two nuclides, with low quantities of 90 Sr impurity and satisfactory elution yields. (author)

New aragonite 87Sr/86Sr records of Mesozoic ammonoids and approach to the problem of N, O, C and Sr isotope cycles in the evolution of the Earth

Science.gov (United States)

Zakharov, Yuri D.; Dril, Sergei I.; Shigeta, Yasunari; Popov, Alexander M.; Baraboshkin, Eugenij Y.; Michailova, Irina A.; Safronov, Peter P.

2018-02-01

New Sr isotope data from well-preserved aragonite ammonoid shell material from the Mesozoic are compared with that from a living Nautilus shell. The prominent negative Sr isotope excursions known from the Middle Permian, Jurassic and Cretaceous probably have their origins in intensive plate tectonic activity, followed by enhanced hydrothermal activity at the mid-ocean ridges (mantle volcanism) which supplied low radiogenic Sr to seawater. The maximum positive (radiogenic) shift in the lower Mesozoic Sr isotope curve (Lower Triassic peak) was likely caused by a significant expansion of dry land surfaces (Dabie-Sulu Triassic orogeny) and their intensive silicate weathering in conditions of extreme warming and aridity in the very end of the Smithian, followed by warm and humid conditions in the late Spathian, which apparently resulted in a significant oceanic input of radiogenic Sr through riverine flux. The comparatively high 87Sr/86Sr ratio obtained from the living Nautilus shell is probably a function of both the Alpine orogeny, which was accompanied by significant continental weathering and input of radiogenic Sr to the oceans, and the weakening of mantle volcanism.

Over-expression of SR-cyclophilin, an interaction partner of nuclear pinin, releases SR family splicing factors from nuclear speckles

International Nuclear Information System (INIS)

Lin, C.-L.; Leu, Steve; Lu, M.-C.; Ouyang Pin

2004-01-01

Pre-mRNA splicing takes place within a dynamic ribonucleoprotein particle called the spliceosome and occurs in an ordered pathway. Although it is known that spliceosome consists of five small nuclear RNAs and at least 50 proteins, little is known about how the interaction among the proteins changes during splicing. Here we identify that SR-cyp, a Moca family of nuclear cyclophilin, interacts and colocalizes with nuclear pinin (pnn), a SR-related protein involving in pre-mRNA splicing. Nuclear pnn interacts with SR-cyp via its C-terminal RS domain. Upon SR-cyp over-expression, however, the subnuclear distribution of nuclear pnn is altered, resulting in its redistribution from nuclear speckles to a diffuse nucleoplasmic form. The diffuse subnuclear distribution of nuclear pnn is not due to epitope masking, accelerated protein turnover or post-translational modification. Furthermore, we find that SR-cyp regulates the subnuclear distribution of other SR family proteins, including SC35 and SRm300, in a similar manner as it does on nuclear pnn. This result is significant because it suggests that SR-cyp plays a general role in modulating the distribution pattern of SR-like and SR proteins, similar to that of Clk (cdc2-like kinase)/STY on SR family splicing factors. SR-cyp might direct its effect via either alteration of protein folding/conformation or of protein-protein interaction and thus may add another control level of regulation of SR family proteins and modification of their functions

Observation of unusual irreversible/reversible effects in a macroscopic cylindrical hole drilled in superconducting Bi-Sr-Ca-Cu-O

International Nuclear Information System (INIS)

Yetis, H.; Kilic, A.; Kilic, K.; Altinkok, A.; Olutas, M.

2008-01-01

Current-voltage (I-V) measurements were carried out for different current sweep rates (dI/dt) of transport current at zero magnetic field (H = 0) and H ≠ 0 in a polycrystalline sample of Bi 1.7 Pb 0.3 Sr 2 Ca 2 Cu 3 O x (BSCCO) with a macroscopic cylindrical hole (CH) drilled. Similar measurements were also performed in the same BSCCO sample without CH for a comparison before drilling CH. For the same values of H, T, and dI/dt taken for both samples, it was observed that hysteresis effects appear in I-V curves upon cycling of transport current in upward and downward directions which contain the increasing and decreasing current values, respectively. However these effects which are seen in I-V curves of BSCCO sample with CH is more prominent than that of the BSCCO sample without CH. Further, the irreversibility effects in I-V curves of the BSCCO sample without CH disappears for H ≠ 0 exhibiting nearly a linear behaviour, whereas the hysteretic behaviour in I-V curves of the BSCCO sample with CH is still observed. This interesting behaviour could be evaluated that macroscopic cylindrical hole improves pinning properties of sample acting as a macroscopic flux pinning center for flux lines

89Sr and 90Sr in atmospheric precipitations in May 1986 in Bucharest-Magurele area

International Nuclear Information System (INIS)

Paunescu, N.; Vata, I.

1987-08-01

Sr-89 and Sr-90 were determined in the fallout of May 1986. The maximum values of 335 Bq/(m 2 * 6 hours) and 110 Bq/(m 2 * 6 hours) were observed at May 2 and 5. Throughout May 1986 a quantity of 860 Bq/m 2 of Sr-90 deposited from the fallout in the Bucharest -Magurele area was determined. (authors)

Treatment with 17-allylamino-17-demethoxygeldanamycin ameliorated symptoms of Bartter syndrome type IV caused by mutated Bsnd in mice.

Science.gov (United States)

Nomura, Naohiro; Kamiya, Kazusaku; Ikeda, Katsuhisa; Yui, Naofumi; Chiga, Motoko; Sohara, Eisei; Rai, Tatemitu; Sakaki, Sei; Uchida, Shinich

2013-11-22

Mutations of BSND, which encodes barttin, cause Bartter syndrome type IV. This disease is characterized by salt and fluid loss, hypokalemia, metabolic alkalosis, and sensorineural hearing impairment. Barttin is the β-subunit of the ClC-K chloride channel, which recruits it to the plasma membranes, and the ClC-K/barttin complex contributes to transepithelial chloride transport in the kidney and inner ear. The retention of mutant forms of barttin in the endoplasmic reticulum (ER) is etiologically linked to Bartter syndrome type IV. Here, we report that treatment with 17-allylamino-17-demethoxygeldanamycin (17-AAG), an Hsp90 inhibitor, enhanced the plasma membrane expression of mutant barttins (R8L and G47R) in Madin-Darby canine kidney cells. Administration of 17-AAG to Bsnd(R8L/R8L) knock-in mice elevated the plasma membrane expression of R8L in the kidney and inner ear, thereby mitigating hypokalemia, metabolic alkalosis, and hearing loss. These results suggest that drugs that rescue ER-retained mutant barttin may be useful for treating patients with Bartter syndrome type IV. Copyright © 2013 Elsevier Inc. All rights reserved.

Hemopoietic stem cell dynamics in 89Sr marrow-ablated mice

International Nuclear Information System (INIS)

Adler, S.S.; Trobaugh, F.E. Jr.; Knospe, W.H.

1977-01-01

89 Sr was used to ablate the marrows of 12- to 16-week-old CAF 1 mice. The CFU-S of their blood, marrows, and spleens were assayed at intervals from days 10 through 56. The effects of splenectomy performed on day 14 or 42 on the numbers of CFU-S in the blood and marrow were also studied. On day 10 after treatment with 89 Sr both the cellularity and CFU-S of the marrow were markedly decreased. Later, especially during the third week after treatment, marrow cellularity increased and by day 56 had returned to 74 percent of normal; the concentration of marrow CFU-S also increased but by day 56 had attained a level of only one-third normal. Thus, replenishment of the marrow's CFU-S lagged behind the repletion of its cellularity. Spleen and blood CFU-S were elevated throughout the 56 days. The number of splenic CFU-S was highest at day 10, decreased somewhat by day 21, and remained remarkably stable thereafter. After splenectomy there was a significant decline in the content of both blood and marrow CFU-S, whereas the reverse occurred in the ''cold'' 88 Sr-treated control group. The results of these studies suggest that in the 89 Sr-irradiated animal the spleen is transformed from a trapper to the prime supplier of CFU-S and that in normal mice the spleen may suppress marrow CFU-S proliferation. An inverse relationship between the size of the pool of mature granulocytes and the number of CFU-S was found, suggesting that the granulocyte compartment may, at least in part, play a role in the regulation of CFU-S proliferation

87Sr/86Sr ratios in hydrothermal waters and deposits from the east pacific rise at 210N

International Nuclear Information System (INIS)

Albarede, F.; Michard, A.; Minster, J.F.; Michard, G.

1981-01-01

87 Sr/ 86 Sr ratios of three hydrothermal waters collected on the East Pacific Rise at 21 0 N define a mixing line between seawater and a hydrothermal end-member at 0.7030 which is derived by seawater-basalt interaction at ca. 350 0 C and water/rock ratio of about 1.5. Sr concentrations are not affected in the process while Mg uptake from seawater is almost complete. Up to 2/3 of this hydrothermal component is involved in anhydrite precipitation while the Sr isotopic ratio in sulfides (chalcopyrite + sphalerite) cannot be distinguished from that of sulfate. It is estimated that ca. 1 x 10 10 moles of strontium are yearly cycled in the hydrothermal systems of mid-oceanic ridges, thereby affecting the 87 Sr/ 86 Sr budget of seawater. Mass balance between river runoff, limestone precipitation and ridge basalt alteration suggests that the 87 Sr/ 86 Sr ratios of the river runoff are in the range 0.7097-0.7113, and are largely dominated by limestone alteration. (orig.)

Synthetic clay excels in 90Sr removal

International Nuclear Information System (INIS)

Komarneni, Sridhar; Kodama, Tatsuya; Paulus, William J.; Carlson, C.

2000-01-01

Tests with actual ground water from Hanford site, and fundamental studies of 2Na + →Sr 2+ exchange equilibria revealed that a synthetic clay is extremely selective for 90 Sr with a high capacity for uptake. Comparative studies with existing Sr selective ion exchangers clearly revealed that the present synthetic clay exhibited the best performance for 90 Sr removal from actual ground water collected from three different locations at Hanford. This novel Sr ion sieve is expected to be useful for the decontamination of the environment after accidental release and contamination with 90 Sr. (c) 2000 Materials Research Society

The influence of Sr on the microstructure, degradation and stress corrosion cracking of the Mg alloys - ZK40xSr.

Science.gov (United States)

Chen, Lianxi; Bin, Yuanhong; Zou, Wenqi; Wang, Xiaojian; Li, Wei

2017-02-01

In the present work, new magnesium (Mg) alloys (Mg-4Zn-0.6Zr-xSr, x=0, 0.4, 0.8, 1.2, 1.6wt%; ZK40xSr) were prepared and studied as potential biodegradable materials. The influence of strontium (Sr) addition on the properties of the new Mg alloys was investigated, which included microstructure, corrosion degradation, and the stress corrosion cracking (SCC) susceptibility. The average grain size of the ZK40Sr was approximately 100µm, which was significantly smaller than that of ZK40 alloy without Sr (402.3±40.2µm). The size of grain boundaries precipitates in the ZK40xSr alloys gradually increased with the increase of Sr content. The grain boundaries finally showed a continuously distribution and net-like shape. The degradation test showed that the average degradation rate of the ZK40xSr alloys increased with the increase of Sr addition. In the case of Mg-4Zn-0.6Zr, the degradation rate was 2.2mgcm -2 day -1 , which was lower than that of Mg-4Zn-0.6Zr-1.6Sr (4.93mgcm -2 day -1 ). When the ZK40xSr alloys were immersed in m-SBF, the rod-like Sr-contained hydroxyapatite (HA) substance was detected, which was known to enhance cell growth around bone implants. The fracture surfaces of the as-cast Mg-4Zn-0.6Zr-1.6Sr were shown intergranular stress corrosion cracking (IGSCC) patterns. The increase of SCC susceptibility of the higher Sr ZK40xSr alloys was attributed to the increase of micro-galvanic corrosion between the α-Mg and the grain boundaries precipitates. The SCC susceptibility values were ≈0.13 and ≈0.41 for the Mg-4Zn-0.6Zr-0.4Sr and the Mg-4Zn-0.6Zr-1.6Sr, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characteristic features of the magnetoresistance in the ferrimagnetic (Sr2FeMoO6-δ) - dielectric (SrMoO4) nanocomposite

Science.gov (United States)

Demyanov, S.; Kalanda, N.; Yarmolich, M.; Petrov, A.; Lee, S.-H.; Yu, S.-C.; Oh, S. K.; Kim, D.-H.

2018-05-01

Magnetic metal-oxide compounds with high values of magnetoresistance (MR) have attracted huge interest for spintronic applications, among which Sr2FeMoO6-δ (SFMO) has been relatively less known compared to the cobaltites and manganites, despite 100% electrons spin-polarization degree and a high Curie temperature. Here, stable fabrication and systematic analysis of nanocomposites based on SFMO with SrMoO4 dielectric sheaths are presented. SFMO-SrMoO4 nanocomposites were fabricated as follows: synthesis of the SFMO single-phase nanopowders by the modified citrate-gel technique; compaction under high pressure; thermal treatment for sheaths formation around grains. The nanocomposite is observed to exhibit a transitional behavior of conductivity from metallic, which is characteristic for the SFMO to semiconductor one in the temperature range 4 - 300K under magnetic fields up to 10T. A negative MR is observed due to the spin-polarized charge carriers tunneling through dielectric sheaths. MR value reaches 43% under 8T at 10κ. The dielectric sheaths thickness was determined to be about 10 nm by electric breakdown voltage value at current-voltage characteristics curves. The breakdown is found to be a reversible process determined by collisional ionization of dielectric atoms in strong electric field depending on knocked-out electrons from the SrMoO4. It was found that MR changes sign in electric breakdown region, revealing the giant magnetoresistive properties.

Surface modeling and chemical solution deposition of SrO(SrTiO3)n Ruddlesden-Popper phases

International Nuclear Information System (INIS)

Zschornak, M.; Gemming, S.; Gutmann, E.; Weissbach, T.; Stoecker, H.; Leisegang, T.; Riedl, T.; Traenkner, M.; Gemming, T.; Meyer, D.C.

2010-01-01

Strontium titanate (STO) is a preferred substrate material for functional oxide growth, whose surface properties can be adjusted through the presence of Ruddlesden-Popper (RP) phases. Here, density functional theory (DFT) is used to model the (1 0 0) and (0 0 1) surfaces of SrO(SrTiO 3 ) n RP phases. Relaxed surface structures, electronic properties and stability relations have been determined. In contrast to pure STO, the near-surface SrO-OSr stacking fault can be employed to control surface roughness by adjusting SrO and TiO 2 surface rumpling, to stabilize SrO termination in an SrO-rich surrounding or to increase the band gap in the case of TiO 2 termination. RP thin films have been epitaxially grown on (0 0 1) STO substrates by chemical solution deposition. In agreement with DFT results, the fraction of particular RP phases n = 1-3 changes with varying heating rate and molar ratio Sr:Ti. This is discussed in terms of bulk formation energy.

Construction of the seawater 87Sr/86Sr curve for the Cenozoic and Cretaceous: supporting data

International Nuclear Information System (INIS)

Koepnick, R.B.; Burke, W.H.; Denison, R.E.; Hetherington, E.A.; Nelson, H.F.; Otto, J.B.; Waite, L.E.

1985-01-01

We present the data used to construct the Cenozoic and Cretaceous portion of the Phanerozoic curve of seawater 87 Sr/ 86 Sr that had been given in summary form by W.H. Burke and coworkers. All Cenozoic samples (128) and 22 Cretaceous samples are foram-nannofossil oozes and limestones from DSDP cores distributed among 13 sites in the Atlantic, Pacific and Indian Oceans, and the Caribbean Sea. Non-DSDP Cretaceous samples (126) include limestone, anhydrite and phosphate samples from North America, Europe and Asia. Determination of the 87 Sr/ 86 Sr value of seawater at particular times in the past is based on comparison of ratios derived from coeval marine samples from widely separated geographic areas. The general configuration of the Cenozoic and Cretaceous curve appears to be strongly influenced by the history of plate interactions and sea-floor spreading. Specific rises and falls in the 87 Sr/ 86 Sr of seawater, however, may be caused by a variety of factors such as variation in lithologic composition of the crust exposed to weathering, configuration and topographic relief of continents, volcanic activity, rate of sea-floor spreading, extent of continental inundation by epeiric seas, and variations in both climate and paleo-oceanographic conditions. Many or all of these factors are probably related to global tectonic processes, yet their combined effect on the temporal variation of seawater 87 Sr/ 86 Sr can complicate a direct plate-tectonic interpretation for portions of the seawater curve. (Auth.)

Astragaloside IV Prevents Cardiac Remodeling in the Apolipoprotein E-Deficient Mice by Regulating Cardiac Homeostasis and Oxidative Stress

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Xiong-Zhi Li

2017-12-01

Full Text Available Background: Hypercholesterolemia is a risk factor for the development of cardiac hypertrophy. Astragaloside IV (AST-IV possesses cardiovascular protective properties. We hypothesize that AST-IV prevents cardiac remodeling with hypercholesterolemia via modulating tissue homeostasis and alleviating oxidative stress. Methods: The ApoE-/- mice were treated with AST-IV at 1 or 10 mg/kg for 8 weeks. The blood lipids tests, echocardiography, and TUNEL were performed. The mRNA expression profile was detected by real-time PCR. The myocytes size and number, and the expressions of proliferation (ki67, senescence (p16INK4a, oxidant (NADPH oxidase 4, NOX4 and antioxidant (superoxide dismutase, SOD were observed by immunofluorescence staining. Results: Neither 1 mg/kg nor 10 mg/kg AST-IV treatment could decrease blood lipids in ApoE-/- mice. However, the decreased left ventricular ejection fraction (LVEF and fractional shortening (FS in ApoE–/– mice were significantly improved after AST-IV treatment. The cardiac collagen volume fraction declined nearly in half after AST-IV treatment. The enlarged myocyte size was suppressed, and myocyte number was recovered, and the alterations of genes expressions linked to cell cycle, proliferation, senescence, p53-apoptosis pathway and oxidant-antioxidants in the hearts of ApoE-/- mice were reversed after AST-IV treatment. The decreased ki67 and increased p16INK4a in the hearts of ApoE-/- mice were recovered after AST-IV treatment. The percentages of apoptotic myocytes and NOX4-positive cells in AST-IV treated mice were decreased, which were consistent with the gene expressions. Conclusion: AST-IV treatment could prevent cardiac remodeling and recover the impaired ventricular function induced by hypercholesterolemia. The beneficial effect of AST-IV might partly be through regulating cardiac homeostasis and anti-oxidative stress.

The Cox-maze IV procedure in its second decade: still the gold standard?

Science.gov (United States)

Ruaengsri, Chawannuch; Schill, Matthew R; Khiabani, Ali J; Schuessler, Richard B; Melby, Spencer J; Damiano, Ralph J

2018-04-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia and the treatment options include medical treatment and catheter-based or surgical interventions. AF is a major cause of stroke, and its prevalence is increasing. The surgical treatment of AF has been revolutionized over the past 2 decades through surgical innovation and improvements in endoscopic imaging, ablation technology and surgical instrumentation. The Cox-maze (CM) procedure, which was developed by James Cox and introduced clinically in 1987, is a procedure in which multiple incisions are created in both the left and the right atria to eliminate AF while allowing the sinus impulse to reach the atrioventricular node. This procedure became the gold standard for the surgical treatment of AF. Its latest iteration is termed the CM IV and was introduced in 2002. The CM IV replaced the previous cut-and-sew method (CM III) by replacing most of the incisions with a combination of bipolar radiofrequency and cryoablation. The use of ablation technologies, made the CM IV technically easier, faster and more amenable to minimally invasive approaches. The aims of this article are to review the indications and preoperative planning for the CM IV, to describe the operative technique and to review the literature including comparisons of the CM IV with the previous cut-and-sew method. Finally, this review explores future directions for the surgical treatment of patients with AF.

Enthalpies of formation of Cd0.917Sr0.083, Cd0.857Sr0.143 and Cd0.667Sr0.333 intermetallic compounds

International Nuclear Information System (INIS)

Agarwal, Renu; Singh, Ziley

2008-01-01

Cadmium is expected to be the solvent for pyrochemical processing of the metallic nuclear fuel. Therefore, thermodynamic properties of cadmium with various fuel and clad elements are of interest. Enthalpies of formation of the intermetallic compounds of Cd-Sr system, Cd 0.917 Sr 0.083 , Cd 0.857 Sr 0.143 and Cd 0.667 Sr 0.333 were determined by precipitation using Calvet calorimeter. Enthalpies of formation of the compounds were found to be -3.05 ± 0.5 kJ mol -1 at 723 K, -14.2 ± 0.7 kJ mol -1 at 843 K and -28.4 ± 0.8 kJ mol -1 at 863 K, respectively. Enthalpies of formation of Cd 0.917 Sr 0.083 and Cd 0.857 Sr 0.143 were also determined by partial enthalpy of formation measurements and the values were found to be -3.9 ± 1.1 kJ mol -1 at 723 K and -13.42 ± 1.2 kJ mol -1 at 843 K, respectively. Miedema model was used to estimate the enthalpies of formation of these compounds and the estimated values were compared with the experimentally determined values

Structural and chemical reactivity modifications of a cobalt perovskite induced by Sr-substitution. An in situ XAS study

International Nuclear Information System (INIS)

Hueso, Jose L.; Holgado, Juan P.; Pereñíguez, Rosa; Gonzalez-DelaCruz, V.M.; Caballero, Alfonso

2015-01-01

LaCoO 3 and La 0.5 Sr 0.5 CoO 3−δ perovskites have been studied by in situ Co K-edge XAS. Although the partial substitution of La(III) by Sr(II) species induces an important increase in the catalytic oxidation activity and modifies the electronic state of the perovskite, no changes could be detected in the oxidation state of cobalt atoms. So, maintaining the electroneutrality of the perovskite requires the generation of oxygen vacancies in the network. The presence of these vacancies explains that the substituted perovskite is now much more reducible than the original LaCoO 3 perovskite. As detected by in situ XAS, after a consecutive reduction and oxidation treatment, the original crystalline structure of the LaCoO 3 perovskite is maintained, although in a more disordered state, which is not the case for the Sr doped perovskite. So, the La 0.5 Sr 0.5 CoO 3−δ perovskite submitted to the same hydrogen reduction treatment produces metallic cobalt, while as determined by in situ XAS spectroscopy the subsequent oxidation treatment yields a Co(III) oxide phase with spinel structure. Surprisingly, no Co(II) species are detected in this new spinel phase. - Highlights: • A Sr-substituted lanthanum cobalt perovskite has been prepared by spray pyrolysis. • It has been established that Co(III) cations are present in both perovskites. • LaCoO 3 is a less reducible phase than the substituted La 0.5 Sr 0.5 CoO 3−δ . • After reoxidation of reduced La 0.5 Sr 0.5 CoO 3−δ , a 100% Co(III) spinel is obtained

Using 87Sr/86Sr ratios to investigate changes in stream chemistry during snowmelt in the Provo River, Utah, USA

Science.gov (United States)

Hale, C. A.; Carling, G. T.; Fernandez, D. P.; Nelson, S.; Aanderud, Z.; Tingey, D. G.; Dastrup, D.

2017-12-01

Water chemistry in mountain streams is variable during spring snowmelt as shallow groundwater flow paths are activated in the watershed, introducing solutes derived from soil water. Sr isotopes and other tracers can be used to differentiate waters that have interacted with soils and dust (shallow groundwater) and bedrock (deep groundwater). To investigate processes controlling water chemistry during snowmelt, we analyzed 87Sr/86Sr ratios, Sr and other trace element concentrations in bulk snowpack, dust, soil, soil water, ephemeral channels, and river water during snowmelt runoff in the upper Provo River watershed in northern Utah, USA, over four years (2014-2017). Strontium concentrations in the river averaged 20 ppb during base flow and decreased to 10 ppb during snowmelt runoff. 87Sr/86Sr ratios were around 0.717 during base flow and decreased to 0.715 in 2014 and 0.713 in 2015 and 2016 during snowmelt, trending towards less radiogenic values of mineral dust inputs in the Uinta Mountain soils. Ephemeral channels, representing shallow flow paths with soil water inputs, had Sr concentrations between 7-20 ppb and 87Sr/86Sr ratios between 0.713-0.716. Snowpack Sr concentrations were generally soils that contain accumulated dust deposits with a less radiogenic 87Sr/86Sr ratio. These results suggest that flow paths and atmospheric dust are important to consider when investigating variable solute loads in mountain streams.

[Content and distribution of active components in cultivated and wild Taxus chinensis var. mairei plants].

Science.gov (United States)

Yu, Shao-Shuai; Sun, Qi-Wu; Zhang, Xiao-Ping; Tian, Sheng-Ni; Bo, Pei-Lei

2012-10-01

Taxus chinensis var. mairei is an endemic and endangered plant species in China. The resources of T. chinensis var. mairei have been excessively exploited due to its anti-cancer potential, accordingly, the extant T. chinensis var. mairei population is decreasing. In this paper, ultrasonic extraction and HPLC were adopted to determine the contents of active components paclitaxel, 7-xylosyltaxol and cephalomannine in cultivated and wild T. chinensis var. mairei plants, with the content distribution of these components in different parts of the plants having grown for different years and at different slope aspects investigated. There existed obvious differences in the contents of these active components between cultivated and wild T. chinensis var. mairei plants. The paclitaxel content in the wild plants was about 0.78 times more than that in the cultivated plants, whereas the 7-xylosyltaxol and cephalomannine contents were slishtly higher in the cultivated plants. The differences in the three active components contents between different parts and tree canopies of the plants were notable, being higher in barks and upper tree canopies. Four-year old plants had comparatively higher contents of paclitaxel, 7-xylosyltaxol and cephalomannine (0.08, 0.91 and 0.32 mg x g(-1), respectively), and the plants growing at sunny slope had higher contents of the three active components, with significant differences in the paclitaxel and 7-xylosyltaxol contents and unapparent difference in the cephalomannine content of the plants at shady slope. It was suggested that the accumulation of the three active components in T. chinensis var. mairei plants were closely related to the sunshine conditions. To appropriately increase the sunshine during the artificial cultivation of T. chinensis var. mairei would be beneficial to the accumulation of the three active components in T. chinensis var. mairei plants.

Preparation and crystal structure of SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/

Energy Technology Data Exchange (ETDEWEB)

Cordier, G; Eisenmann, B; Schaefer, H [Technische Hochschule Darmstadt (Germany, F.R.). Fachbereich Anorganische Chemie und Kernchemie

1976-10-01

SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/ have been prepared and analytically and structurally characterized. SrCu/sub 2/Sb/sub 2/ crystallizes tetragonal in the CaBe/sub 2/Ge/sub 2/ structure type. SrZnBi/sub 2/ has its own structure type. In both structures the transition metal atoms form with the semimetal atoms tetragonal pyramids, which are connected by common edges of the basis to twodimensional sheets. These sheets are separated in the case of SrCu/sub 2/Sb/sub 2/ by single sheets of strontium atoms, in the case of SrZnBi/sub 2/ by double sheets of strontium atoms in which fourfold nets of Bi atoms are located.

Spectroscopic and electric dipole properties of Sr+Ar and SrAr systems including high excited states

Science.gov (United States)

Hamdi, Rafika; Abdessalem, Kawther; Dardouri, Riadh; Al-Ghamdi, Attieh A.; Oujia, Brahim; Gadéa, Florent Xavier

2018-01-01

The spectroscopic properties of the fundamental and several excited states of Sr+Ar and SrAr, Van der Waals systems are investigated by employing an ab initio method in a pseudo-potential approach. The potential energy curves and the spectroscopic parameters are displayed for the 1-10 2Σ+, 1-6 2Π and 1-3 2Δ electronic states of the Sr+Ar molecule and for the 1-6 1Σ+, 1-4 3Σ+, 1-3 1,3Π and 1-3 1,3Δ states of the neutral molecule SrAr. In addition, from these curves, the vibrational levels and their energy spacing are deduced for Σ+, Π and Δ symmetries. The spectra of the permanent and transition dipole moments are studied for the 1,3Σ+ states of SrAr, which are considered to be two-electron systems and 2Σ+ states of the single electron Sr+Ar ion. The spectroscopic parameters obtained for each molecular system are compared with previous theoretical and experimental works. A significant correlation revealed the accuracy of our results.

Sr - an element shows the way - Applications of Sr isotopes for provenance, tracing and migration (Invited)

Science.gov (United States)

Prohaska, T.; Irrgeher, J.; Zitek, A.; Teschler Nicola, M.

2010-12-01

Strontium - named after the small Scottish town Strontian - as such is an element with little popularity. Firstly described by Martin Heinrich Klaproth in 1798, the metal is used in metallurgy to some extent whereas its compounds are interesting in glass industries, electronics and pyrotechnics. The element has chemical similarity to Ca and makes up 1/60 of the earth’s amount of the latter. Nonetheless, it is its isotopic composition which makes Sr so interesting for a large number of scientists. The natural composition of the four naturally occurring isotopes (84Sr, 86Sr 87Sr and 88Sr) varies in nature due to the radioactive decay of 87Rb to 87Sr. Thus, it was early recognized as geochronometer especially in Ca rich matrices. With increasing precision of applied methodology, the natural variation of the 87Sr/86Sr isotope ratio (analyzed at first mainly by thermal ionization mass spectrometry (TIMS)) became more and more popular in provenance studies. The natural variation of the ratio is mainly determined by the geological age and the original composition of the rock and can be used therefore as fingerprint of the local geology. The ratio is transferred with no significant fractionation via the water into plants and finally via the food chain into animal and human tissues (especially bones and teeth). As the element is chemically similar to Ca, it appears in most matrices. The use for provenance studies is supported by the fact that the long half life (4.8 x 1010 years) does not lead to an alteration during the time scales which are investigated (from recent samples to human or animal skeletal remains which date back up to 30.000 BC). The uniqueness of the system besides the natural variation is defined by the ubiquity in nature and the relatively high (and thus measurable) elemental concentration in most tissues. It was finally the advent of multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) which augmented the number of applications

Epitaxial growth and thermodynamic stability of SrIrO3/SrTiO3 heterostructures

Science.gov (United States)

Groenendijk, D. J.; Manca, N.; Mattoni, G.; Kootstra, L.; Gariglio, S.; Huang, Y.; van Heumen, E.; Caviglia, A. D.

2016-07-01

Obtaining high-quality thin films of 5d transition metal oxides is essential to explore the exotic semimetallic and topological phases predicted to arise from the combination of strong electron correlations and spin-orbit coupling. Here, we show that the transport properties of SrIrO3 thin films, grown by pulsed laser deposition, can be optimized by considering the effect of laser-induced modification of the SrIrO3 target surface. We further demonstrate that bare SrIrO3 thin films are subject to degradation in air and are highly sensitive to lithographic processing. A crystalline SrTiO3 cap layer deposited in-situ is effective in preserving the film quality, allowing us to measure metallic transport behavior in films with thicknesses down to 4 unit cells. In addition, the SrTiO3 encapsulation enables the fabrication of devices such as Hall bars without altering the film properties, allowing precise (magneto)transport measurements on micro- and nanoscale devices.

Synthesis of Ag-loaded SrTiO_3/TiO_2 heterostructure nanotube arrays for enhanced photocatalytic performances

International Nuclear Information System (INIS)

Hu, Zijun; Chen, Da; Zhan, Xiaqiang; Wang, Fang; Qin, Laishun; Huang, Yuexiang

2017-01-01

In this work, the effect of loading Ag nanoparticles on the photocatalytic activity of SrTiO_3/TiO_2 nanotube arrays (TNTAs) was investigated. TNTAs were partially transformed to SrTiO_3 through a hydrothermal treatment, which could preserve the tubular structure of TNTAs, and then, Ag nanoparticles were well deposited on the surface of SrTiO_3/TNTAs heterostructure by a chemical reduction process. Compared to the TNTAs sample, the Ag-loaded SrTiO_3/TNTAs sample showed significantly enhanced photocatalytic activities for photodegradation of rhodamine B. The enhanced photocatalytic activity of Ag-loaded SrTiO_3/TNTAs could be attributed to the increased optical absorption as well as the efficient charge transfer and separation of photogenerated electron-hole pairs induced by the SrTiO_3/TNTAs heterojunction and the Schottky barrier between metallic Ag and SrTiO_3/TNTAs. On the basis of the trapping experiments, the possible photocatalytic mechanism was also discussed. (orig.)

Endoscopic treatment of grades IV and V vesicoureteral reflux with two bulking substances: Dextranomer hyaluronic acid copolymer versus polyacrylate polyalcohol copolymer in children.

Science.gov (United States)

Kocaoglu, Canan

2016-10-01

We aimed at evaluating the efficacy and complications of two bulking substances: dextranomer/hyaluronic acid copolymer(Dx/Ha;Dexell®) versus polyacrylate polyalcohol copolymer(PPC;Vantris®) in subureteric injection treatment of children with high grades (grades IV-V) vesicoureteral reflux(VUR). Data of patients undergoing endoscopic treatment of high grade VUR (January 2009-August 2015) were retrospectively investigated. Patients with high grade VUR caused by posterior urethral valve, duplex system, paraureteral diverticula and neurogenic bladder were excluded. Classical subureteric injection method (STING) was used. Seventy-three children (45 girls and 28 boys) who had 88 refluxing renal units (RRUs) with grades IV-V VUR (n=64/n=24) underwent endoscopic treatment using Dx/Ha (n=63 RRUs) and PPC (n=25 RRUs). Mean age of patients in Dx/Ha and PPC groups were 6 (3) and 6 (3.75) year (p=0.81), and volumes of these substances given were 1.3 (1) and 1 (0.5) mL (p=0.003), respectively. Overall, for the first endoscopic injection, success rate of grades IV-V VUR per RRU was 53.9% with Dx/Ha, compared to 80% in PPC-injected group, (p=0.024). Late ureterovesical junction obstruction developed only in one patient in PPC-injected group. No ureteral obstruction was observed in Dx/Ha-injected group. Endoscopic injection of PPC resulted in significantly higher success rate, compared to Dx/Ha in subureteric injection treatment of children with high grade VUR. However, the development of late ureterovesical junction obstruction should also be taken into account in PPC injection. Copyright © 2016 Elsevier Inc. All rights reserved.

Treatment of melasma with low fluence, large spot size, 1064-nm Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser for the treatment of melasma in Fitzpatrick skin types II-IV.

Science.gov (United States)

Brown, Alia S; Hussain, Mussarat; Goldberg, David J

2011-12-01

Melasma is a common condition affecting over six million American women. Treatment of dermal or combined melasma is difficult and does not respond well to conventional topical therapies. Various light sources have been used recently in the treatment of melasma including fractionated ablative and non-ablative lasers as well as intense pulse light. We report the use of low fluence, large spot size Q-switched, Nd:Yag laser for the treatment of melasma in skin types II-IV.

87Sr/86Sr ratios in permo-carboniferous sea water from the analyses of well-preserved brachiopod shells

International Nuclear Information System (INIS)

Popp, B.N.; Anderson, T.F.

1986-01-01

Sr isotopic analyses of well-preserved portions of Permo-Carboniferous brachiopods distributed globally confirm the general shape of the Sr isotope age curve established by previous workers for this time interval. There is little variation between the SR isotopic composition of unaltered portions of brachiopods and that of portions of the same shell interpreted to be diagenetically altered (based on cathodoluminescence, elemental, and stable isotopic data). However, the Sr isotopic composition in diagenetically altered micritic matrix adjacent to the shell is more radiogenic. The Sr isotopic composition in the unaltered portions of calcitic megafossils has potential as a stratigraphic tool. (author)

Effects of Nb doping level on the electronic transport, photoelectric effect and magnetoresistance across La0.5Ca0.5MnO3/Nb:SrTiO3 junctions

Science.gov (United States)

Wang, J. F.; Jiang, Y. C.; Chen, M. G.; Gao, J.

2013-12-01

Heterojunctions composed of La0.5Ca0.5MnO3 and Nb doped SrTiO3 were fabricated, and the effects of the Nb doping level on their electronic transport, photoelectric effect, and magnetoresistance were investigated. A lower doping concentration of Nb led to better rectifying properties and higher open circuit voltages. The I-V curves for La0.5Ca0.5MnO3/0.7 wt. % Nb-SrTiO3 showed a negligible response to magnetic fields for all temperatures, whereas La0.5Ca0.5MnO3/0.05 wt. % Nb-SrTiO3 exhibited distinct magnetoresistance, which depended on both the bias voltage and temperature. These results are discussed with the assistance of conventional semiconductor theories.

Climate and climate-related issues for the safety assessment SR-Site

International Nuclear Information System (INIS)

2010-12-01

The purpose of this report is to document current scientific knowledge on climate and climate-related conditions, relevant to the long-term safety of a KBS-3 repository, to a level required for an adequate treatment in the safety assessment SR-Site. The report also presents a number of dedicated studies on climate and selected climate-related processes of relevance for the assessment of long term repository safety. Based on this information, the report presents a number of possible future climate developments for Forsmark, the site selected for building a repository for spent nuclear fuel in Sweden (Figure 1-1). The presented climate developments are used as basis for the selection and analysis of SR-Site safety assessment scenarios in the SR-Site main report /SKB 2011/. The present report is based on research conducted and published by SKB as well as on research reported in the general scientific literature

Climate and climate-related issues for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

The purpose of this report is to document current scientific knowledge on climate and climate-related conditions, relevant to the long-term safety of a KBS-3 repository, to a level required for an adequate treatment in the safety assessment SR-Site. The report also presents a number of dedicated studies on climate and selected climate-related processes of relevance for the assessment of long term repository safety. Based on this information, the report presents a number of possible future climate developments for Forsmark, the site selected for building a repository for spent nuclear fuel in Sweden (Figure 1-1). The presented climate developments are used as basis for the selection and analysis of SR-Site safety assessment scenarios in the SR-Site main report /SKB 2011/. The present report is based on research conducted and published by SKB as well as on research reported in the general scientific literature

Development of Composite Adsorbents for LLW Treatment and Their Adsorption Properties for Cs and Sr - 13127

Energy Technology Data Exchange (ETDEWEB)

Susa, Shunsuke; Mimura, Hitoshi [Dept. of Quantum Science and Energy Engineering, Graduate School of Engineering, Tohoku University, Aramaki-Aza-Aoba 6-6-01-2, Sendai, 980-8579 (Japan); Ito, Yoshiyuki; Saito, Yasuo [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, 2-4 Shirakata Shirone, Naka-gun, Ibaraki, 319-1195 (Japan)

2013-07-01

In this study, the composite adsorbents (KCoFC-NM (NM: natural mordenite), KCoFC-SG (SG: porous silica gel), AMP-SG and so on) were prepared by impregnation-precipitation methods. As for the distribution properties, the largest K{sub d,Cs} value of 3.8 x 10{sup 4} cm{sup 3}/g was obtained for KCoFC-SG (Davi.) composite. KCoFC-SG (NH, MB5D) and T-KCFC also had relatively large K{sub d,Cs} values above 1.0 x 10{sup 4} cm{sup 3}/g. The uptake rate of Cs{sup +} ions was examined by batch method. KCoFC-SG (NH, MB5D) and AMP-SG (Davi.) had relatively large uptake rate of Cs{sup +}, and the uptake attained equilibrium within 1 h. The maximum uptake capacity of Cs{sup +} ions was estimated to be above 0.5 mmol/g for KCoFC-NM and KCoFC-CP composites. KCoFC-X composite had a relatively large uptake capacity of Cs{sup +} ions (0.23 mmol/g > 0.17 mmol/g (T-KCFC)) and this composite also had a selectivity towards Sr{sup 2+} ions; KCoFC-X is effective adsorbent for both Cs{sup +} and Sr{sup 2+} ions. The largest value of K{sub d,Sr} was estimated to be 218 cm{sup 3}/g for titanic acid-PAN. Titanic acid-PAN had the largest uptake rate of Sr{sup 2+} ions, and the uptake attained equilibrium within 8 h. Adsorbability of other nuclides was further examined by batch method. All adsorbents had adsorbability for Rb{sup +} and RuNO{sup 3+} ions. KCoFC-SG (NH), KCoFC-CP and T-KCFC had higher selectivity towards Cs{sup +} than other adsorbents; these adsorbents had adsorbability to Cs{sup +} ions even in the presence of Ba{sup 2+}, Ca{sup 2+} and Mg{sup 2+} ions. The separation factor of K{sub d,Sr}/K{sub d,Ba} for titanic acid-PAN was about 1, indicating that the K{sub d,Sr} for titanic acid-PAN tends to decrease with Ba{sup 2+} concentration. As for the breakthrough properties, the largest 5 % breakpoint and 5 % breakthrough capacity of Cs{sup +} ions were estimated to be 47.1 cm{sup 3} and 0.07 mmol/g for the column of KCoFC-SG (NH), respectively. The order of 5 % breakthrough capacity

Review of SR 97 performance assessment

International Nuclear Information System (INIS)

Glynn, P.D.

2000-01-01

This review has identified many technical problems in the SR 97 performance assessment. The general impression of this reviewer is that SKB has been disingenuous in its performance assessment effort. It has not cited important differences of opinion with its own views. Furthermore, there are many inconsistencies in the SR 97 report that all together leave the impression that there are many more uncertainties in the SR 97 performance assessment than SKB would perhaps care to admit. Additionally, despite SKB's statements to the contrary, many of the analyses conducted for the SR 97 performance assessment can be clearly shown not to have been based on 'conservative' assumptions. Finally, SKB has made little effort to consider possible coupling effects between their different scenarios in SR 97. This is a serious flaw in the SR 97 performance assessment. The comments in this review should not be taken to imply that the KBS-3 nuclear waste disposal method will not be able to meet the safety and radiation protection requirements which SKI and SSI have specified in recent years. Instead, my conclusion is simply that the SR 97 performance assessment of the KBS-3 method would have been more believable had it been based on a forthright and comprehensive discussion of facts, uncertainties and opinions, and on a more conservative choice of assumptions. As it stands, the SR 97 performance assessment is not very credible

87Sr/86Sr isotopes in grapes of different cultivars: A geochemical tool for geographic traceability of agriculture products.

Science.gov (United States)

Tescione, Ines; Marchionni, Sara; Casalini, Martina; Vignozzi, Nadia; Mattei, Massimo; Conticelli, Sandro

2018-08-30

87 Sr/ 86 Sr was determined on fresh red and white grapes, soils and rocks from three selected vineyards to verify the isotopic relationships between the fruit of the vine and geologic substrata of vineyards. 87 Sr/ 86 Sr were determined on sampled grapes of four different harvest years and different grape varieties, on bioavailable fraction of soils, on whole soils, and on bedrocks from the geo-pedological substratum of the vineyards. The vineyards chosen for the experimental works belong to an organic farming winery and thus cultivation procedures were strictly controlled. Grapes were sampled during the harvests of four different but consecutive years with 87 Sr/ 86 Sr that does not change reflecting the values of the soil bioavailable fraction. No variations among grapes from different vine cultivars were observed. A strict isotope relationship with soil bio-available fraction was observed. These findings demonstrate the reliability of 87 Sr/ 86 Sr, even at a very small scale, for food products geographic origin assessment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development of 87Sr/86Sr maps as targeted strategy to support wine quality.

Science.gov (United States)

Durante, Caterina; Bertacchini, Lucia; Cocchi, Marina; Manzini, Daniela; Marchetti, Andrea; Rossi, Maria Cecilia; Sighinolfi, Simona; Tassi, Lorenzo

2018-07-30

This study summarizes the results obtained from a systematic and long-term project aimed at the development of tools to assess the provenance of food in the oenological sector. In particular, 87 Sr/ 86 Sr isotope ratios were measured on statistically representative set of soils, vine branches and wines sampled in the production district of Modena, worldwide known for the Lambrusco wines production. The obtained data were used to build strontium isotopic maps able to objectively support the Lambrusco PDO wines origin as well as other products of the Modena district. Finally, a strong relationship was found between the 87 Sr/ 86 Sr isotope ratios of soils and vine branches on a large scale, highlighting and confirming once more the idea that plants can also represent an optimal sampling device to support geographical traceability. Copyright © 2018 Elsevier Ltd. All rights reserved.

Review of SR 97

International Nuclear Information System (INIS)

Voss, C.I.

2000-01-01

The safety analysis conducted by SKB for SR 97 is impressive in terms of both scale and content. In addition to an eventual solution to Sweden's nuclear waste isolation question, much general scientific knowledge of real value in other applications will be created as a by-product of SKB's efforts. This review focuses on those geoscience aspects of SR 97 that have the most important effects on radionuclide release from each barrier. Indeed, SR 97 elucidates the most important geoscience parameters that control releases from the near field and the far field; these comprise mainly the transport resistance parameter, and the sorption coefficients for each nuclide, the matrix diffusion coefficient, and the Darcy flux. The Main Report is the most important document in SR 97 inasmuch as it is the only one that brings together all of the supporting work to answer the question of safety. Unfortunately pervading the good supporting work done is the impression that the Main Report is not balanced, that it emphasizes optimistic aspects and downplays the negative. SKB specifies 3 main requirements to guarantee proper repository function: a non-oxidizing subsurface environment, temperatures less than 100 C, and a mechanically stable low-permeability buffer surrounding the canisters. The first and third requirements are not thoroughly proven by SKB. One source of near-field doubt stems from the consequences of combinations of scenarios in which several negative events are linked, while the effect of each scenario is mainly evaluated only independently in SR 97. More pertinently, disastrous breakdown of complex systems may occur due to a chain of linked failures. For example, in the glacial scenario: high ground-water flow (possible ablation of buffer and high fluid transport), change in ground-water chemistry (even the possibility of oxidizing conditions), new flow paths, significant changes in mechanical stress and possible motion along faults (which may also generate new flow

Synthesis of homogeneous Ca0.5Sr0.5FeO2.5+δ compound using a mirror furnace method

International Nuclear Information System (INIS)

Mahboub, M.S.; Zeroual, S.; Boudjada, A.

2012-01-01

Graphical abstract: X-ray diffraction pattern indexing of Ca 0.5 Sr 0.5 FeO 2.5+δ powder sample obtained by mirror furnace method after thermal treatment. Highlights: ► A homogenous compound Ca 0.5 Sr 0.5 FeO 2.5+δ has been synthesized for the first time by a mirror furnace method. ► Ca 0.5 Sr 0.5 FeO 2.5+δ powder sample is perfectly homogenous, confirmed by X-ray diffraction, Raman spectroscopy and EDS technique. ► The thermal treatment of Ca 0.5 Sr 0.5 FeO 2.5+δ powder sample can increase their average grain sizes. -- Abstract: A new synthesis method using melting zone technique via the double mirror furnace around 1600 °C is used to obtain homogenous brownmillerite compounds Ca 1−x Sr x FeO 2.5+δ in the range 0.3 ≤ x ≤ 0.7. These compounds play important role in understanding the mystery of the oxygen diffusion in the perovskite-related oxides. We have successfully solved the miscibility gap problem by synthesizing a good quality of homogenous powder samples of Ca 0.5 Sr 0.5 FeO 2.5+δ compound. Our result was confirmed by X-rays diffraction, Raman spectroscopy and energy dispersive spectroscopy analysis. Thermal treatment was also applied until 800 °C under vacuum to confirm again the homogeneity of powder samples, improve its quality and show that no decomposition or return to form Ca- and Sr-enriched microdomains takes place as a result of phase separation.

Preparation of Sr adsorptive fiber by impregnating with crown ether derivative for 90Sr measurement

International Nuclear Information System (INIS)

Horita, Takuma; Asai, Shiho; Hanzawa, Yukiko; Kitatsuji, Yoshihiro; Konda, Miki; Saito, Kyoichi; Fujiwara, Kunio; Sugo, Takanobu

2017-01-01

A Sr adsorption fiber was prepared for rapid analysis of 90 Sr content in the fiber using radiation-induced emulsion graft polymerization and subsequent chemical modification. A polyethylene fiber with a diameter of 13 μm was first immersed in a methanol solution of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and polyoxyethylene sorbitol ester (Tween20) as a surfactant for the graft-polymerization of GMA. Octadecylamine was then bound to a polymer chain extending from the fiber surface, providing hydrophobicity to the polymer chain. Dicyclohexano-18-crown-6 (DCH18C6) was finally impregnated onto the polymer chain via a hydrophobic interaction between the octadecyl moiety of the polymer chain and the cyclohexyl moiety of DCH18C6. The fiber surface structure, characterized by DCH18C6 molecules loosely entangled with polymer chains, allowed for the rapid adsorption of Sr ions at an adsorption rate of approximately 100-times higher than that of a commercially available Sr-selective resin (Sr Resin ® ). (author)

Trends in prescribing systemic treatment and overall survival for non-small cell lung cancer stage IIIB/IV in the Netherlands : 2008-2012

NARCIS (Netherlands)

Peters, Bas J M; Cramer-Vd Welle, Christine M; Smit, Arthur A J; Schramel, Franz M N H; van de Garde, Ewoudt M W

2017-01-01

BACKGROUND: The present study aims to give a detailed overview of day-to-day practice in the systemic treatment of NSCLC stage IIIB/IV and its clinical outcomes in six large teaching hospitals in the Netherlands in the period 2008-2012. METHODS: A retrospective observational cohort study was

Preparation of 90Sr-90Y generator

International Nuclear Information System (INIS)

Jin Xiaohai; Yu Haibin; Zhang Jinming; Zhang Peixin; Lin Qiongfang

1990-01-01

In recent years, 90 Y has been considered as one of the best radionuclides for tumor radioimmunotherapy when chelated to tumor-associated antibodies. This evaluation is based on the superior properties of this radionuclide (suitable half-life, pure β-ray emitter of intermediate energy, stable daughters, and suitable chemical properties) and because it is available as a radionuclide generator product by decay of its 28a parent 90 Sr. The experimental conditions of 90 Sr- 90 Y generator are described. The elution efficiency of 90 Sr- 90 Y generator reaches 98%. One of the most important problems is the 90 Sr contamination breakthrough from the generator. The level of 90 Sr contamination must be controlled to the clinical standard. The cation exchange resin 732 (100-150 mesh) was successfully used for the separation of 90 Y from 90 Sr. The method used by the authors provides a 90 Y-HAc solution which is very simple and safe for administration to the patients. 90 Y was separated from 90 Sr almost completely, the level of the 90 Sr contamination per 740 MBq 90 Y product was only 0.74 kBq. However the toxicity of 90 Sr is extremely high, the human life-time permissible dose is 74 kBq, then 740 MBq of 90 Y is allowed to be administrated to a patient for 50-100 times

Studies on the leukemogenic and immunologic effects of radiostrontium (90Sr) and x rays in mice

International Nuclear Information System (INIS)

Ito, K.; Nagao, K.; Kawamura, Y.; Yokoro, K.

1976-01-01

The leukemogenic effect of internal irradiation with radiostrontium ( 90 Sr) was compared with that of external irradiation with x rays in ICR/JCL mice. Immunological, hematological, and cytogenetical changes were also studied during the preleukemic period in mice treated with 90 Sr or with x rays. A single intraperitoneal injection of 1.0 μCi of 90 Sr per gram of body weight resulted in leukemia in 62 percent of the mice. Only one of the 90 Sr-induced leukemias was of thymic origin. The occurrence of the leukemia was not affected by thymectomy. A fractionated whole-body x-irradiation of 680 R induced leukemia in 77 percent of the mice; the majority of the leukemias were of thymic origin. Although x-irradiation over the thymic region was ineffective in eliciting leukemia, a combined treatment of 90 Sr and local x-irradiation of the thymus was effective in inducing thymic lymphomas. The single intraperitoneal administration of 90 Sr caused an enhancement of both direct and indirect splenic plaque-forming cell (PFC) responses to sheep red blood cells, lasting for 35 days after treatment. No changes were observed in delayed-type hypersensitivity to picryl chloride. Thymectomy caused no appreciable effect in these immune responses. The fractionated whole-body x-irradiation rapidly depressed both PFC and delayed-type hypersensitivity responses, which persisted for a long period, especially in thymectomized mice. An abrupt increase of chromosomally aberrant cells in the thymus 60 days after the last x-irradiation was preceded by an increase of aberrant population in the bone marrow. On the other hand, a long-lasting appearance of aberrant population in the bone marrow and lymph nodes was observed in 90 Sr-injected mice

90Sr- 90Y and 89Sr beta radioactivity measurement in milk samples using a proportional counter

International Nuclear Information System (INIS)

Mananes, A.; Perez Santos, C.; Martinez Churiaque, F.

1987-01-01

A thin window glas flow proportional counter is used to measure the 90 Sr- 90 Y and 89 Sr beta radioactivity in milk samples. A chemical procedure is used to separate strontium-yttrium from the other radionuclides present in milk. A calculation of the total efficiency of the system is performed which includes an empirical estimation of the backscattering factor. The calibration of the whole process allows the determination of the 90 Sr activity within 10% relative error in spite of uncertainties in the recovery yields of strontium and yttrium. No 89 Sr activity has been detected, and the mean value obtained for the 90 Sr activity in nine milk samples of Cantabria is 0.115 Bq/1 with a minimum detectable activity of 0.0105 Bq. (author) 18 refs

Sorption behaviour of Cs, Sr radionuclides in the presence of various anions and surfactants in solutions

International Nuclear Information System (INIS)

Davydov, Yu.P.; Toropov, I.G.; Vasilevskaya, T.V.

1997-01-01

The state of 137 Cs and 90 Sr radionuclides was studied in solutions of different compositions to develop appropriate methodology and technology for treatment of spent decontamination solutions. Complex physico-chemical methods were used for this study. Particular attention was paid to the sorption of 137 Cs and 90 Sr on different natural and synthetic inorganic sorbents, as the most specific and selective sorbents for separation of these radionuclides from different solutions. Sorption of CS and Sr on different fractions of soil was also studied in connection with development of rehabilitation methods for contaminated territories. (author). 2 refs, 20 tabs

Observation of unusual irreversible/reversible effects in a macroscopic cylindrical hole drilled in superconducting Bi-Sr-Ca-Cu-O

Energy Technology Data Exchange (ETDEWEB)

Yetis, H. [Department of Physics, Turgut Gulez Research Laboratory, Abant Izzet Baysal University, 14280 Bolu (Turkey)], E-mail: yetis_h@ibu.edu.tr; Kilic, A.; Kilic, K.; Altinkok, A.; Olutas, M. [Department of Physics, Turgut Gulez Research Laboratory, Abant Izzet Baysal University, 14280 Bolu (Turkey)

2008-09-15

Current-voltage (I-V) measurements were carried out for different current sweep rates (dI/dt) of transport current at zero magnetic field (H = 0) and H {ne} 0 in a polycrystalline sample of Bi{sub 1.7}Pb{sub 0.3}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (BSCCO) with a macroscopic cylindrical hole (CH) drilled. Similar measurements were also performed in the same BSCCO sample without CH for a comparison before drilling CH. For the same values of H, T, and dI/dt taken for both samples, it was observed that hysteresis effects appear in I-V curves upon cycling of transport current in upward and downward directions which contain the increasing and decreasing current values, respectively. However these effects which are seen in I-V curves of BSCCO sample with CH is more prominent than that of the BSCCO sample without CH. Further, the irreversibility effects in I-V curves of the BSCCO sample without CH disappears for H {ne} 0 exhibiting nearly a linear behaviour, whereas the hysteretic behaviour in I-V curves of the BSCCO sample with CH is still observed. This interesting behaviour could be evaluated that macroscopic cylindrical hole improves pinning properties of sample acting as a macroscopic flux pinning center for flux lines.

Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition

International Nuclear Information System (INIS)

Jungbauer, M.; Hühn, S.; Moshnyaga, V.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.

2014-01-01

We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO 3 ) n (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO 3 (001) substrates by means of a sequential deposition of Sr-O/Ti-O 2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO 3 ) 4 block at the level of 2.4%. This identifies the SrTiO 3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy

Is there a role for hyperbaric oxygen as primary treatment for grade IV radiation-induced haemorrhagic cystitis? a prospective pilot-feasibility study and review of literature

Energy Technology Data Exchange (ETDEWEB)

Dellis, Athanasios [Surgical Department, University of Athens, Aretaieion Hospital (Greece); Deliveliotis, Charalambos [Urologic Department, University of Athens, Sismanoglio General Hospital (Greece); Kalentzos, Vasileios; Vavasis, Pavlos; Skolarikos, Andreas [Diving and Hyperbaric Oxygen Department, Naval and Veterans Hospital, Athens (Greece)

2014-05-15

Purpose: To examine the safety and efficacy of hyperbaric oxygen as the primary treatment for Grade IV radiation-induced haemorrhagic cystitis. Materials and Methods: Hyperbaric oxygen was prospectively applied as a primary treatment option in 11 patients with Grade IV radiation cystitis. Primary endpoint was the incidence of complete and partial response to treatment. Secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results: All patients completed therapy without complications for a mean follow-up of 17.82 months (range 3 to 34). Mean number of sessions needed was 32.8 (range 27 to 44). Complete and partial response rate was 81.8% and 18.2%, respectively. However, in three patients the first treatment session was not either sufficient or durable giving a 72.7% rate of durable effect. Interestingly, all 9 patients with complete response received therapy within 6 months of the haematuria onset compared to the two patients with partial response who received therapy at 8 and 10 months from the haematuria onset, respectively (p = 0.018). The need for blood transfusion (p = 0.491) and the total radiation dose (p = 0.259) were not correlated to success-rate. One patient needed cystectomy, while all patients were alive at the end of follow-up. Conclusions: Early primary use of hyperbaric oxygen to treat radiation-induced grade IV cystitis is an effective and safe treatment option. (author)

Is there a role for hyperbaric oxygen as primary treatment for grade IV radiation-induced haemorrhagic cystitis? a prospective pilot-feasibility study and review of literature

International Nuclear Information System (INIS)

Dellis, Athanasios; Deliveliotis, Charalambos; Kalentzos, Vasileios; Vavasis, Pavlos; Skolarikos, Andreas

2014-01-01

Purpose: To examine the safety and efficacy of hyperbaric oxygen as the primary treatment for Grade IV radiation-induced haemorrhagic cystitis. Materials and Methods: Hyperbaric oxygen was prospectively applied as a primary treatment option in 11 patients with Grade IV radiation cystitis. Primary endpoint was the incidence of complete and partial response to treatment. Secondary endpoints included the duration of response, the correlation of treatment success-rate to the interval between the onset of haematuria and initiation of therapy, blood transfusion need and total radiation dose, the number of sessions to success, the avoidance of surgery and the overall survival. Results: All patients completed therapy without complications for a mean follow-up of 17.82 months (range 3 to 34). Mean number of sessions needed was 32.8 (range 27 to 44). Complete and partial response rate was 81.8% and 18.2%, respectively. However, in three patients the first treatment session was not either sufficient or durable giving a 72.7% rate of durable effect. Interestingly, all 9 patients with complete response received therapy within 6 months of the haematuria onset compared to the two patients with partial response who received therapy at 8 and 10 months from the haematuria onset, respectively (p = 0.018). The need for blood transfusion (p = 0.491) and the total radiation dose (p = 0.259) were not correlated to success-rate. One patient needed cystectomy, while all patients were alive at the end of follow-up. Conclusions: Early primary use of hyperbaric oxygen to treat radiation-induced grade IV cystitis is an effective and safe treatment option. (author)

Peculiarities of Sr-90 migration in the environment

International Nuclear Information System (INIS)

Romanov, G.N.; Stukin, D.A.; Aleksakhin, R.M.

1991-01-01

The Eastern Urals radioactive track which formed as a result of the Kyshtym accident constituted a natural experimental base for studying the dynamics of Sr-90 behaviour and migration in the environment. Sr-90 behaviour in soil depends on the processes involved in its physical migration horizontally (water runoff, wind transport) and vertically (effective diffusion), on the intensity with which the physico-chemical forms of strontium change, and primarily on Sr-90 incorporation into the soil-absorptive complex. Over 30 years the effective diffusion processes led to downward displacement of Sr-90 in undisturbed soil to a depth of 30 to 50 cm. In 1988 84-94% of the Sr-90 was located in the 10 cm layer as against 90% in the 2 cm layer in the initial 1 or 2 years. The amount of Sr-90 in mobile forms in leached chernozem and grey forest soil hardly changed over time, amounting to between 76 and 90%. In the first 5-10 years Sr-90 surface water runoff was about 0.2% (and Sr-90 wind resuspension 0.1-1.0%) per year of the Sr-90 inventory per unit area. Due to Sr-90 loss from the top soil layer the water runoff and wind resuspension processes decreased exponentially, halving every 4 to 5 years. In most cases, Sr-90 transfer from soil to plants via the roots does not involve discrimination of Sr-90 with regard to calcium, and therefore the Sr-90 accumulation level in various species of natural and agricultural plants depends on their calcium requirements and the amount of exchangeable calcium in the soil. This made it possible to work out quantitative indices for forecasting Sr-90 accumulation in various species of plants for given types of soil. As Sr-90 moves through the trophic chains (including the agricultural one) we find - depending on whether two adjoining links discriminate against it or not as regards calcium - that some organisms reject it while others concentrate it. When restoring farming on the contaminated territory the fact that cattle discriminated against Sr

Cancer in the oropharynx: Cost calculation of different treatment modalities for controlled primaries, relapses and grade III/IV complications

International Nuclear Information System (INIS)

Nijdam, Wideke; Levendag, Peter; Noever, Inge; Groot, Carin Uyl-de; Agthoven, Michel van

2005-01-01

Background and purpose: This paper presents a model for cost calculation using the different treatment modalities for oropharyngeal (OPh) cancers used in our hospital. We compared full hospital costs, the associated costs of localregional relapses (LRR) and/or treatment related grade III/IV complications. Materials and methods: Patients with OPh cancer are treated in the Erasmus MC preferably by an organ function preservation protocol. That is, by external beam radiation therapy (EBRT) followed by a brachytherapy (BT) boost, and neck dissection in case of N+ disease (BT-group: 157 patients). If BT is not feasible, resection with postoperative EBRT (S-group [S=Surgery]: 110 patients) or EBRT-alone (EBRT-group: 77 patients) is being pursued. Actuarial localregional control (LRC), disease free survival (DFS) and overall survival (OS) at 5-years were calculated according to the Kaplan-Meier method. The mean costs per treatment group for diagnosis, primary Tx per se, follow-up, (salvage of) locoregional relapse (LRR), distant metastasis (DM), and/or grade III/IV complications needing clinical admission, were computed. Results: For the BT-, S-, or EBRT treatment groups, LRC rates at 5-years were 85, 82, and 55%, for the DFS, 61, 48, and 43%, and for the OS 65, 52, and 40%, respectively. The mean costs of primary Tx in case of the BT-group is EURO 13,466; for the S-group EURO 24,219, and EURO 12,502 for the EBRT-group. The mean costs of S (the main salvage modality) for a LRR of the BT group or EBRT-group, were EURO 17,861 and EURO 15,887, respectively. The mean costs of clinical management of Grade III/IV complications were EURO 7184 (BT-group), EURO 16,675 (S-group) and EURO 6437 (EBRT-group). Conclusion: The clinical outcome illustrates excellent LRC rates at 5-years for BT (85%), as well as for S (82%). The relatively low 55% LRC rate at 5-years for EBRT probably reflects a negative selection of patients. It is of interest that the total mean costs of patients alive

Test Review: Advanced Clinical Solutions for WAIS-IV and WMS-IV

Science.gov (United States)

Chu, Yiting; Lai, Mark H. C.; Xu, Yining; Zhou, Yuanyuan

2012-01-01

The authors review the "Advanced Clinical Solutions for WAIS-IV and WMS-IV". The "Advanced Clinical Solutions (ACS) for the Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV; Wechsler, 2008) and the "Wechsler Memory Scale-Fourth Edition" (WMS-IV; Wechsler, 2009) was published by Pearson in 2009. It is a…

Applicability of 87Sr/86Sr in examining return flow of irrigation water in highly agricultural watersheds in Japan

Science.gov (United States)

Yoshida, T.; Nakano, T.; Shin, K. C.; Tsuchihara, T.; Miyazu, S.; Kubota, T.

2017-12-01

Water flows in watersheds containing extensive areas of irrigated paddies are complex because of the substantial volumes involved and the repeated cycles of water diversion from, and return to, streams. For better management of low-flow conditions, numerous studies have attempted to quantify the return flow using the stable isotopes of water; however, the temporal variation in these isotopic compositions due to fractionation during evaporation from water surfaces hinders their application to watersheds with extensive irrigated paddies. In this study, we tested the applicability of the strontium isotopes (87Sr/86Sr, hereafter Sr ratio) for studying hydrological processes in a typical agricultural watershed located on the alluvial fan of the Kinu River, namely the Gogyo River, in central Japan. The Sr ratio of water changes only because of interactions with the porous media it flows through, or because of mixing with water that has different Sr ratios. We sampled water both at a single rice paddy, and on the watershed scale in the irrigated and non-irrigated periods. The soil water under the paddy decreased as sampling depth increased, and the soil water at a depth of 1.5 m showed a similar Sr ratio to the spring. The water sampled in the drainage channel with a concrete lined bottom showed a similar Sr ratio to the irrigation water, whereas that with a soil bottom was plotted between the plots of the irrigation water and shallow aquifer. These results suggest the Sr ratio decreases as it mixes with the soil water through percolation; whereas the Sr ratio will be less likely to change when water drains from paddies via surface pathways. The streamflow samples were plotted linearly on the Sr ratio and 1/Sr plot, indicating that the streamflow was composed of two end-members; the irrigation water and the shallow aquifer. The continuous decline in the Sr ratio along the stream suggests an exfiltration of water from the shallow aquifers. The stream water during the non

Development of compact synchrotron radiation facilities TELL-TERAS, NIJI-I∼IV, at ETL

International Nuclear Information System (INIS)

Tomimasu, T.

1990-01-01

At the Electrotechnical Laboratory (ETL) four compact storage rings, TERAS, NIJI-I∼III, have been already constructed and a compact storage ring, NIJI-IV, with long straight sections for a free electron laser (FEL) experiment will be completed in 1990. The 0.8-GeV ETL storage ring is called TERAS; Tsukuba Electron Ring for Accelerating and Storage. TERAS has been operated since Oct. 1981 for researches on radiometric standards, dissociative photoionization, photodissociation of sulfur containing molecules, solid state physics, ULSI lithography, generation of polarized SR and gamma-rays and for FEL experiment using an transverse optical klystron (TOK). A 10-T three pole wiggler will be installed in 1991 at the straight section where the TOK is installed. NIJI-I is a 0.27-GeV compact ring. NIJI is a Japanese verb meaning 'rainbow' in English. It has been operated from Feb. 1986 to March 1989 for machine study of beam storage higher than 0.5 A at low energies below 0.15-GeV. NIJI-II is a 0.6-GeV conventional type compact ring. It has been operated in Aug. 1989 and will be used for chemical vapor deposition (CVD) and polarized SR experiments. NIJI-III is a 0.62-GeV superconducting type ring. It will be used for ULSI lithography experiments. Before the superconducting coils are installed, NIJI-III with conventional type magnets has been already constructed and operated in June 1989. NIJI-III with the superconducting ones is now operated in June 1990. NIJI-IV is a 0.5-GeV conventional type compact ring with straight sections longer than 7m where a 6.2-m long TOK is installed to achieve UV FEL experiment. (author)

Combined effect of angioinfarction with immunotherapy in patients with stage IV renal cell carcinoma

International Nuclear Information System (INIS)

Oh, Joo Hyeong; Yoon, Yup; Jeong, Yu Mee; Ko, Young Tae; Chang, Sung Goo

1994-01-01

To assess the combined effectiveness of angioinfarction and immunotherapy for improving survival in patients with stage IV renal cell carcinoma. During the past 3 years, 13 patients of stage IV renal cell carcinoma were treated with angioinfarction and immunotherapy. Angioinfarction was performed on these 13 patients using absolute ethanol and occlusive balloon catheter. After angioinfarction, Interferon alpha was used for immunotherapy. For our analysis, 12 control patients of stage IV renal cell carcinoma without treatment were included in the study. Survival has been calculated according to the Kaplan and Meier method. The 1 year survival rate and median survival time in patients treated with angioinfarction and immunotherapy, were 46% and 13 months and in patients without treatment, 16% and 4 months, respectively. The combined treatment of angioinfarction and immunotherapy is of considerable value for improving survival in patients with stage IV renal cell carcinoma

Lack of association of the HMGA1 IVS5-13insC variant with type 2 diabetes in an ethnically diverse hypertensive case control cohort

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Karnes Jason H

2013-01-01

Full Text Available Abstract Background Recently, the high-mobility group A1 gene (HMGA1 variant IVS5-13insC has been associated with type 2 diabetes, but reported associations are inconsistent and data are lacking in Hispanic and African American populations. We sought to investigate the HMGA1-diabetes association and to characterize IVS5-13insC allele frequencies and linkage disequilibrium (LD in 3,070 Caucasian, Hispanic, and African American patients from the INternational VErapamil SR-Trandolapril STudy (INVEST. Methods INVEST was a randomized, multicenter trial comparing two antihypertensive treatment strategies in an ethnically diverse cohort of hypertensive, coronary artery disease patients. Controls, who were diabetes-free throughout the study, and type 2 diabetes cases, either prevalent or incident, were genotyped for IVS5-13insC using Taqman®, confirmed with Pyrosequencing and Sanger sequencing. For LD analysis, genotyping for eight additional HMGA1 single nucleotide polymorphisms (SNPs was performed using the Illumina® HumanCVD BeadChip. We used logistic regression to test association of the HMGA1 IVS5-13insC and diabetes, adjusted for age, gender, body mass index, and percentage European, African, and Native American ancestry. Results We observed IVS5-13insC minor allele frequencies consistent with previous literature in Caucasians and African Americans (0.03 in cases and 0.04 in controls for both race/ethnic groups, and higher frequencies in Hispanics (0.07 in cases and 0.07 in controls. The IVS5-13insC was not associated with type 2 diabetes overall (odds ratio 0.98 [0.76-1.26], p=0.88 or in any race/ethnic group. Pairwise LD (r2 of IVS5-13insC and rs9394200, a SNP previously used as a tag SNP for IVS5-13insC, was low (r2=0.47 in Caucasians, r2=0.25 in Hispanics, and r2=0.06 in African Americans. Furthermore, in silico analysis suggested a lack of functional consequences for the IVS5-13insC variant. Conclusions Our results suggest that IVS5-13ins

Clinical experience with radiation enhancement by hyperbaric oxygen in children with recurrent neuroblastoma stage IV

International Nuclear Information System (INIS)

Voute, P.A.; Kleij, A.J. van der; De Kraker, J.; Hoefnagel, C.A.; Tiel-van Buul, M.M.C.; Gennip, H. van

1995-01-01

The high risk group of patients with neuroblastoma are children over 1 year with stage IV disease. Most series report a maximum of 20% survival at 5 years. For recurrent neuroblastoma stage IV, cure rates are not reported in the literature, but they are nil. Any treatment for recurrent neuroblastoma stage IV remains a therapeutic dilemma. The outcome of radiation therapy is variable. A very important factor in tumour treatment remains tumour hypoxia, and others, such as metabolic factors, also play a role. Combined application of radiation modifiers may influence the final survival rate. In an attempt to improve the survival of recurrent neuroblastoma stage IV, hyperbaric oxygen and radioionated meta-Iodobenzylguanidine (MIBG) was used in a clinical setting. Although survival may not be used as a determinant of the usefulness of a treatment for stage IV neuroblastoma disease, a better one is not available. In this study, at 28 months, a cumulative probability of survival of 32% was recorded for patients treated with [ 131 I]MIBG and hyperbaric oxygen compared to 12% for [ 131 I]MIBG treatment alone. These preliminary results are promising but further studies are needed to reveal substantial therapeutic gain. (Author)

Direct complexonometric determination of thorium (IV), uranium (IV), neptunium (IV), plutonium (IV) by titration of diethylenetriaminepentaacetic acid with xylenol orange as indicator

International Nuclear Information System (INIS)

Rykov, A.G.; Piskunov, E.M.; Timofeev, G.A.

1975-01-01

The purpose of the present work was to develop a method of determining Th(IV), U(IV), Np(N) and Pu(IV) in acid solutions by titration with diethylenetriamine pentacetic acid, the indicator being xylenol orange. It has been established that Th, U, Np and Pu can be determined to within 0.5-1.5%. Th and U in quantities of tens of milligrams can be determined with greater accuracy, attaining hundredths of one per cent. During titration the determination is not hindered by singly- and doubly-charged metal ions, trivalent lanthanides and actinides, except plutonium. The proposed method can be used to determine U(IV) in the presence of considerable quantities of U(VI) and Np(IV) in the presence of Np(V). Total concentrations of uranium or neptunium are determined by reducing uranium (VI) or neptunium (V) by a standard method (for example, using metallic lead, cadmium or zinc amalgam) to the tetravalent state and applying the method described in the paper. (E.P.)

Protection against SR 4233 (tirapazamine) aerobic cytotoxicity by the metal chelators desferrioxamine and tiron

International Nuclear Information System (INIS)

Herscher, L.L.; Krishna, M.C.; Cook, J.A.

1994-01-01

Metal chelating agents and antioxidants were evaluated as potential protectors against aerobic SR 4233 cytotoxicity in Chinese hamster V79 cells. The differential protection of aerobic and hypoxic cells by two metal chelators, desferrrioxamine and Tiron, is discussed in the context of their potential use in the on-going clinical trials with SR 4233. Cytotoxicity was evaluated using clonogenic assay. SR 4233 exposure was done in glass flasks as a function of time either alone or in the presence of the following agents: superoxide dismutase, catalase, 5,5-dimethyl-1-pyrroline, Trolox, ICRF-187, desferrioxamine, Tiron (1,2-dihydroxybenzene-3,5-disulfonate), and ascorbic acid. Experiments done under hypoxic conditions were carried out in specially designed glass flasks that were gassed with humidified nitrogen/carbon dioxide mixture and with a side-arm reservoir from which SR 4233 was added to cell media after hypoxia was obtained. Electron paramagnetic resonance studies were also performed. Electron paramagnetic resonance and spectrophotometry experiments suggest that under aerobic conditions SR 4233 undergoes futile redox cycling to produce superoxide. Treatment of cells during aerobic exposure to SR 4233 with the enzymes superoxide dismutase and catalase, the spin trapping agent DMPO, the water-soluble vitamin E analog Trolox, and the metal chelator ICRF-187 provided little or no protection against aerobic SR 4233 cytotoxicity. However, two other metal chelators, desferrioxamine and Tiron afforded significant protection against minimal protection to hypoxic cells treated with SR 4233. One potential mechanism of aerobic cytotoxicity is redox cycling of SR 4233 with molecular oxygen resulting in several potentially toxic oxidative species that overburden the intrinsic intracellular detoxification systems such as superoxide dismutase, catalase, and glutathione peroxidase. 23 refs., 4 figs., 1 tab

Strontium (Sr) and silver (Ag) loaded nanotubular structures with combined osteoinductive and antimicrobial activities.

Science.gov (United States)

Cheng, Hao; Xiong, Wei; Fang, Zhong; Guan, Hanfeng; Wu, Wei; Li, Yong; Zhang, Yong; Alvarez, Mario Moisés; Gao, Biao; Huo, Kaifu; Xu, Jiangwen; Xu, Na; Zhang, Chengcheng; Fu, Jijiang; Khademhosseini, Ali; Li, Feng

2016-02-01

Two frequent problems are associated with the titanium surfaces of bone/dental implants: lack of native tissue integration and associated infection. These problems have prompted a significant body of research regarding the modification of these surfaces. The present study describes a hydrothermal treatment for the fabrication of strontium (Sr) and silver (Ag) loaded nanotubular structures with different tube diameters on titanium surfaces. The Sr loading from a Sr(OH)2 solution was regulated by the size of the inner diameter of the titanium nanotubes (NT) (30nm or 80nm, formed at 10V or 40V, respectively). The quantity of Ag was adjusted by immersing the samples in 1.5 or 2.0M AgNO3 solutions. Sr and Ag were released in a controllable and prolonged matter from the NT-Ag.Sr samples, with negligible cytotoxicity. Prominent antibacterial activity was observed due to the release of Ag. Sr incorporation enhanced the initial cell adhesion, migration, and proliferation of preosteoblast MC3T3-E1 cells. Sr release also up-regulated the expression of osteogenic genes and induced mineralization, as suggested by the presence of more mineralized calcium nodules in cells cultured on NT-Ag.Sr surfaces. In vivo experiments showed that the Sr-loaded samples accelerated the formation of new bone in both osteoporosis and bone defect models, as confirmed by X-ray, Micro-CT evaluation, and histomorphometric analysis of rats implanted with NT-Ag.Sr samples. The antibacterial activity and outstanding osteogenic properties of NT-Ag.Sr samples highlight their excellent potential for use in clinical applications. Two frequent problems associated with Ti surfaces, widely used in orthopedic and dental arenas, are their lack of native tissue integration and risk of infection. We describe a novel approach for the fabrication of strontium (Sr) and silver (Ag) loaded nanotubular structures on titanium surfaces. A relevant aspect of this work is the demonstration of long-lasting and controllable

The influence of Sr content in calcium phosphate coatings

International Nuclear Information System (INIS)

Lindahl, Carl; Pujari-Palmer, Shiuli; Hoess, Andreas; Ott, Marjam; Engqvist, Håkan; Xia, Wei

2015-01-01

In this study calcium phosphate coatings with different amounts of strontium (Sr) were prepared using a biomineralization method. The incorporation of Sr changed the composition and morphology of coatings from plate-like to sphere-like morphology. Dissolution testing indicated that the solubility of the coatings increased with increased Sr concentration. Evaluation of extracts (with Sr concentrations ranging from 0 to 2.37 μg/mL) from the HA, 0.06Sr, 0.6Sr, and 1.2Sr coatings during in vitro cell cultures showed that Sr incorporation into coatings significantly enhanced the ALP activity in comparison to cells treated with control and HA eluted media. These findings show that calcium phosphate coatings could promote osteogenic differentiation even in a low amount of strontium. - Highlights: • Calcium phosphate coating doping with low Sr contents was prepared via a biomineralization process. • The solubility of the coatings increased with increased Sr concentration. • Present findings show the potential that Sr has on promoting osteogenic differentiation even in a low amount

Hypofractionated stereotactic body radiation therapy for elderly patients with stage IIB–IV nonsmall cell lung cancer who are ineligible for or refuse other treatment modalities

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Karam SD

2014-10-01

Full Text Available Sana D Karam,1 Zachary D Horne,2 Robert L Hong,2 Don McRae,2 David Duhamel,3 Nadim M Nasr2 1Department of Radiation Oncology, University of Colorado, Denver, CO, USA; 2Department of Radiation Oncology, 3Department of Pulmonary/Critical Care Medicine, Virginia Hospital Center, Arlington, VA, USA Objective: In elderly patients with stage IIB–IV nonsmall cell lung cancer who cannot tolerate chemotherapy, conventionally fractionated radiotherapy is the treatment of choice. We present our experience with hypofractionated stereotactic body radiation therapy (SBRT in the treatment of this patient population. Methods: Thirty-three patients with a median age of 80 years treated with fractionated SBRT were retrospectively analyzed. Most patients were smokers and had preexisting lung disease and either refused treatment or were ineligible. A median prescribed dose of 40 Gy was delivered to the prescription isodose line over a median of five treatments. The majority of patients (70% did not receive chemotherapy. Results: With a median follow-up of 9 months (range: 4–40 months, the actuarial median overall survival (OS and progression-free survival were 12 months for both. One year actuarial survival outcomes were 75%, 58%, 44%, and 48% for local control, regional control, progression-free survival, and OS, respectively. Increased volume of disease was a statistically significant predictor of worse OS. Three patients developed a grade 1 cough that peaked 3 weeks after treatment and resolved within 1 month. One patient developed grade 1 tracheal mucositis and three patients developed grade 1 pneumonitis. Both resolved 6 weeks after treatment. Three patients died within the first month of treatment, but the cause of death did not appear to be related to the treatment. Conclusion: Hypofractionated SBRT is a relatively safe and convenient treatment option for elderly patients with inoperable stage IIB–IV nonsmall cell lung cancer. However, given the small

Ion exchange kinetics of alkaline earths on Zr(IV) arsenosilicate cation exchanger

International Nuclear Information System (INIS)

Varshney, K.G.; Agrawal, S.; Varshney, K.

1984-01-01

A new approach based on the Nernst-Planck equations was applied to study the ion exchange kinetics for the exchange reactions of Mg(II), Ca(II), Sr(II) and Ba(II) with H + -ions at various temperatures on the zirconium(IV) arsenosilicate phase. Under the conditions of particle diffusion, the rate of exchange was found to be independent of the metal ion concentration at and above 0.1 M in aqueous medium. Energy and entropy of activation were determined and found to vary linearly with the ionic radii and mobilities of alkaline earths, a unique feature observed for an inorganic ion exchanger. The results are useful for predicting the ion exchange processes occurring on the surface of an inorganic material of the type studied. (author)

Chemical nature of implant-derived titanium(IV) ions in synovial fluid

International Nuclear Information System (INIS)

Silwood, Christopher J.L.; Grootveld, Martin

2005-01-01

Previous investigations have indicated a deleterious leakage of Ti(III) and/or Ti(IV) species from Ti-Al-V alloy joint prostheses into adjacent tissue, synovium or synovial fluid (SF) in vivo. In view of the importance of the particular chemical nature of such complexes in determining their biological activity, we have employed high field proton ( 1 H) NMR spectroscopy to 'speciate' Ti(IV) in inflammatory SF. Treatment of osteoarthritic SF samples with increasing concentrations of Ti(IV) (0.10-1.03 mM [TiO(C 2 O 4 ) 2 ] 2- ) gave rise to a specific broadening of the citrate proton resonances, indicating that this bioavailable oxygen-donor ligand plays an important role in complexing implant-derived Ti(IV). 1 H NMR analysis of Ti(IV)-loaded SF samples subsequently treated with a large excess of ascorbate (0.05 M) showed that this added Ti(IV) chelator was only poorly effective in removing this metal ion from Ti(IV)-citrate/Ti(IV)-oxycitrate complexes. The results obtained here provide evidence for complexation of the low-molecular-mass (non-protein-bound) fraction of implant-derived Ti(IV) by citrate in vivo

The inverse F-BAR domain protein srGAP2 acts through srGAP3 to modulate neuronal differentiation and neurite outgrowth of mouse neuroblastoma cells.

Directory of Open Access Journals (Sweden)

Yue Ma

Full Text Available The inverse F-BAR (IF-BAR domain proteins srGAP1, srGAP2 and srGAP3 are implicated in neuronal development and may be linked to mental retardation, schizophrenia and seizure. A partially overlapping expression pattern and highly similar protein structures indicate a functional redundancy of srGAPs in neuronal development. Our previous study suggests that srGAP3 negatively regulates neuronal differentiation in a Rac1-dependent manner in mouse Neuro2a cells. Here we show that exogenously expressed srGAP1 and srGAP2 are sufficient to inhibit valporic acid (VPA-induced neurite initiation and growth in the mouse Neuro2a cells. While ectopic- or over-expression of RhoGAP-defective mutants, srGAP1(R542A and srGAP2(R527A exert a visible inhibitory effect on neuronal differentiation. Unexpectedly, knockdown of endogenous srGAP2 fails to facilitate the neuronal differentiation induced by VPA, but promotes neurite outgrowth of differentiated cells. All three IF-BAR domains from srGAP1-3 can induce filopodia formation in Neuro2a, but the isolated IF-BAR domain from srGAP2, not from srGAP1 and srGAP3, can promote VPA-induced neurite initiation and neuronal differentiation. We identify biochemical and functional interactions of the three srGAPs family members. We propose that srGAP3-Rac1 signaling may be required for the effect of srGAP1 and srGAP2 on attenuating neuronal differentiation. Furthermore, inhibition of Slit-Robo interaction can phenocopy a loss-of-function of srGAP3, indicating that srGAP3 may be dedicated to the Slit-Robo pathway. Our results demonstrate the interplay between srGAP1, srGAP2 and srGAP3 regulates neuronal differentiation and neurite outgrowth. These findings may provide us new insights into the possible roles of srGAPs in neuronal development and a potential mechanism for neurodevelopmental diseases.

In-Depth Review of Symptoms, Triggers, and Treatment of Occipital Migraine Headaches (Site IV).

Science.gov (United States)

Ascha, Mona; Kurlander, David E; Sattar, Abdus; Gatherwright, James; Guyuron, Bahman

2017-06-01

This study reports the surgical technique and efficacy of deactivation of occipital-triggered migraine headaches. In addition, it reports the effect of surgical deactivation of occipital-triggered migraine headaches on migraine triggers and associated symptoms other than pain. One hundred ninety-five patients undergoing surgery for occipital-triggered migraine headaches performed by a single surgeon, and followed for at least 1 year, were analyzed. Median regression adjusted for age, sex, and follow-up time was used to determine postoperative reduction in occipital-specific Migraine Headache Index, which is the product of migraine duration, frequency, and severity. Reduction in migraine-days was also measured. The association between symptom or trigger resolution and occipital-specific Migraine Headache Index reduction was studied by logistic regression. Details of surgical treatment are discussed and complication rates reported. Eighty-two percent of patients (n = 160) reported successful surgery at least 12 months postoperatively (mean follow-up, 3.67 years). Eighty-six percent (n = 168) had successful surgery as measured by migraine-days. Fifty-two percent reported complete occipital-triggered migraine headaches elimination. Symptoms resolving with successful surgery beyond headache include being bothered by light and noise, feeling lightheaded, difficulty concentrating, vomiting, blurred/double vision, diarrhea, visual aura, numbness and tingling, speech difficulty, and limb weakness (p occipital-triggered migraine headaches provides long-lasting migraine relief. Successful site IV surgery is associated with changes in specific symptoms and triggers. This can assist in trigger avoidance and aid occipital-triggered migraine headache trigger-site identification. Therapeutic, IV.

Mapping and characterization of wheat stem rust resistance genes SrTm5 and Sr60 from Triticum monococcum.

Science.gov (United States)

Chen, Shisheng; Guo, Yan; Briggs, Jordan; Dubach, Felix; Chao, Shiaoman; Zhang, Wenjun; Rouse, Matthew N; Dubcovsky, Jorge

2018-03-01

The new stem rust resistance gene Sr60 was fine-mapped to the distal region of chromosome arm 5A m S, and the TTKSK-effective gene SrTm5 could be a new allele of Sr22. The emergence and spread of new virulent races of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici; Pgt), including the Ug99 race group, is a serious threat to global wheat production. In this study, we mapped and characterized two stem rust resistance genes from diploid wheat Triticum monococcum accession PI 306540. We mapped SrTm5, a previously postulated gene effective to Ug99, on chromosome arm 7A m L, completely linked to Sr22. SrTm5 displayed a different race specificity compared to Sr22 indicating that they are distinct. Sequencing of the Sr22 homolog in PI 306540 revealed a novel haplotype. Characterization of the segregating populations with Pgt race QFCSC revealed an additional resistance gene on chromosome arm 5A m S that was assigned the official name Sr60. This gene was also effective against races QTHJC and SCCSC but not against TTKSK (a Ug99 group race). Using two large mapping populations (4046 gametes), we mapped Sr60 within a 0.44 cM interval flanked by sequenced-based markers GH724575 and CJ942731. These two markers delimit a 54.6-kb region in Brachypodium distachyon chromosome 4 and a 430-kb region in the Chinese Spring reference genome. Both regions include a leucine-rich repeat protein kinase (LRRK123.1) that represents a potential candidate gene. Three CC-NBS-LRR genes were found in the colinear Brachypodium region but not in the wheat genome. We are currently developing a Bacterial Artificial Chromosome library of PI 306540 to determine which of these candidate genes are present in the T. monococcum genome and to complete the cloning of Sr60.

Chernobyl 90Sr in bilberries from Poland

International Nuclear Information System (INIS)

Mietelski, J.W.; Vajda, N.

1997-01-01

As part of a detailed survey on the contamination of Polish forests 90 Sr activity concentrations were determined in bilberries. Elevated 90 Sr levels were found in several samples from north-eastern Poland. The calculated maximum 90 Sr surface contamination was 2 kBq*m -2 . The correlation between 90 Sr and 137 Cs concentrations in bilberries was good for two sets of samples originating from two geographical areas of Poland indicating the local differences in radionuclide depositions from Chernobyl fallout. (author)

Preparation and up-conversion luminescence of SrAlF{sub 5}:Yb{sup 3+}/Er{sup 3+} nanorods

Energy Technology Data Exchange (ETDEWEB)

Zhao, Jun [College of Life Science, Dalian Nationalities University, Dalian, Liaoning 116600 (China); Department of Physics, Dalian Maritime University, Dalian, Liaoning 116026 (China); Hua, Ruinian, E-mail: rnhua@dlnu.edu.cn [College of Life Science, Dalian Nationalities University, Dalian, Liaoning 116600 (China); Zhang, Wei; Feng, Zhiqing; Tang, Dongxin; Na, Liyan [College of Life Science, Dalian Nationalities University, Dalian, Liaoning 116600 (China); Chen, Baojiu, E-mail: chenmbj@sohu.com [Department of Physics, Dalian Maritime University, Dalian, Liaoning 116026 (China)

2014-03-05

Graphical abstract: The SrAlF{sub 5} nanorods co-doped with various Yb{sup 3+}/Er{sup 3+} concentrations was synthetized via a microemulsion-hydrothermal process for the first time. It was found that the optimum doping concentration of Yb{sup 3+} and Er{sup 3+} in SrAlF{sub 5} matrix was about 4 mol%. Furthermore, the temperature effect of upconversion luminescence was investigated. It was also found that the post heat-treatment could greatly improve upconversion luminescence. Highlights: • SrAlF{sub 5}:Yb{sup 3+}/Er{sup 3+} nanorods were synthesized via a microemulsion-hydrothermal process. • Crystal structure and morphology were characterized by using XRD and FESEM. • The upconversion luminescence intensity depend on LD working current was studied. • The post heat-treatment could greatly improve upconversion luminescence. -- Abstract: Yb{sup 3+} and Er{sup 3+} co-doped SrAlF{sub 5} nanorods with average diameter of 35 nm and average length of 400 nm were synthesized via a microemulsion-hydrothermal process, and their crystal structure and morphology were characterized by using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. The optimum doping concentration of Yb{sup 3+}/Er{sup 3+} in SrAlF{sub 5} matrix was about 4 mol%. The upconversion luminescence intensity dependence on the laser diode (LD) working current was studied and the possible upconversion mechanism was analyzed. Furthermore, the temperature effect of upconversion luminescence was investigated. It was also found that the post heat-treatment could greatly improve upconversion luminescence.

New methods for the preparation and dielectric properties of La{sub 2−x}Sr{sub x}NiO{sub 4} (x = 1/8) ceramic

Energy Technology Data Exchange (ETDEWEB)

Chupakhina, T.I., E-mail: chupakhina@ihim.uran.ru [Institute of Solid State Chemistry, UB RAS, 91, Pervomaiskaya str., Ekaterinburg 620990 (Russian Federation); Kadyrova, N.I. [Institute of Solid State Chemistry, UB RAS, 91, Pervomaiskaya str., Ekaterinburg 620990 (Russian Federation); Melnikova, N.V. [Ural Federal University, 19, Mira str., Ekaterinburg (Russian Federation); Gyrdasova, O.I. [Institute of Solid State Chemistry, UB RAS, 91, Pervomaiskaya str., Ekaterinburg 620990 (Russian Federation); Yakovleva, E.A. [Ural Federal University, 19, Mira str., Ekaterinburg (Russian Federation); Zainulin, Yu.G. [Institute of Solid State Chemistry, UB RAS, 91, Pervomaiskaya str., Ekaterinburg 620990 (Russian Federation)

2016-05-15

Highlights: • A new fuel in solution combustion synthesis of fine powder La{sub 15/8}Sr{sub 1/8}NiO{sub 4}. • Changes in the morphology of the ceramic La{sub 15/8}Sr{sub 1/8}NiO{sub 4} after thermobaric treatment. • Changes in structural parameters of the La{sub 15/8}Sr{sub 1/8}NiO{sub 4} after thermobaric treatment. • Increase of the dielectric constant of the thermobaric treated ceramic La{sub 15/8}Sr{sub 1/8}NiO{sub 4}. • Using of dielectric modulus and impedance formalisms, of equivalent circuits method. - Abstract: The perovskite-type oxide La{sub 2−x}Sr{sub x}NiO{sub 4} (x = 1/8) was prepared by a new precursor route. The reaction proceeds in the self-ignition mode. Single-phase powder and gas-tight ceramic samples can be produced by single annealing of decomposition products. It was shown that as a result of thermobaric treatment of La{sub 2−x}Sr{sub x}NiO{sub 4} (x = 1/8) the solid solution La{sub 2−x}Sr{sub x}NiO{sub 4} with a higher concentration of strontium and the second phase La{sub 3}Ni{sub 2}O{sub 7} are formed. Short-term (5 min) thermobaric treatment (P = 2.5 GPa) at t° = 900 °C changes the unit cell parameters, but is not accompanied by structural transitions. At the same time, morphological restructuring of the sample occurs—the agglomerates delaminate into thin plates crystals. It was established that the permittivity of the material exposed to thermobaric treatment is much higher compared to that of the sample annealed at atmospheric pressure and virtually does not depend on frequency in a wide temperature range.

Modification of Sr on 4004 Aluminum Alloy

Science.gov (United States)

Guo, Erjun; Cao, Guojian; Feng, Yicheng; Wang, Liping; Wang, Guojun; Lv, Xinyu

2013-05-01

As a brazing foil, 4004 Al alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. To improve the plasticity of 4004 Al alloy and subsequently improve the productivity of 4004 Al foil or 434 composite foil, 4004 Al alloy was modified by Al-10%Sr master alloy. Modification effects of an additional amount of Sr, modification temperature, and holding time on 4004 aluminum alloy were studied by orthogonal design. The results showed that the greatest impact parameter of 4004 aluminum alloy modification was the additional amount of Sr, followed by holding time and modification temperature. The optimum modification parameters obtained by orthogonal design were as follows: Sr addition of 0.04%, holding time of 60 min, and modification temperature of 760°C. The effect of Sr addition on modification was analyzed in detail based on orthogonal results. With increasing of Sr addition, elongation of 4004 alloy increased at first, and decreased after reaching the maximum value.

Losses of Sr/sup 90/, Sr/sup 89/, and I/sup 131/ from fallout-contaminated plants

Energy Technology Data Exchange (ETDEWEB)

Martin, W E

1964-11-01

During the early period following local fallout, and during periods of maximal worldwide fallout, the entry of radionuclides into terrestrial food-chains is due primarily to the external contamination of plants and secondarily to the uptake of radionuclides from contaminated soil. Studies were undertaken to estimate the rates of radionuclide loss from fallout-contaminated vegetation and hence from the diets of herbivores living in a fallout field. On the fifth, fifteenth, thirtieth, and sixtieth days after an underground nuclear explosion (Operation Sedan) at the Nevada Test Site, plant samples were collected from twenty representative locations in the fallout field and analyzed to determined the concentrations (pc/g dry wt) of /sup 90/Sr, /sup 89/Sr, and /sup 131/I at the times of collections. While the radioactive half lives of /sup 90/Sr, /sup 89/Sr, and /sup 131/I are approximately 27.7 years, 53 days, and 8.04 days respectively, their average effective half-lives on fallout-contaminated plants, during the period from 5 to 30 days after the detonation, were 27.8 days, 17.8 days, and 5.0 days respectively. Losses of /sup 90/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 90/Sr and /sup 89/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 131/I were attributed to radioactive decay, to mechanical disturbance, and to the vaporization of /sup 131/I from the fallout particles retained on foliage.

Taxol: A complex diterpenoid natural product with an evolutionarily ...

African Journals Online (AJOL)

In addition to Taxus sp, taxoids are also synthesized by various endophytic fungi, which often live in association with Taxus trees, thus raising questions about the evolutionary origin of this complex diterpenoid pathway. In the future, it may be possible to improve taxoid synthesis through the genetic modification of Taxus cell ...

Final report from VFL technologies for the pilot-scale thermal treatment of Lower East Fork Poplar Creek floodplain soils: LEFPC appendices, volume 1, appendix I-IV

International Nuclear Information System (INIS)

1994-09-01

This document contains Appendix I-IV for the pilot-scale thermal treatment of lower East Fork Poplar Creek floodplain soils. Included are calibration records; quality assurance; soils characterization; pilot scale trial runs

Experimental evidence shows no fractionation of strontium isotopes ((87)Sr/(86)Sr) among soil, plants, and herbivores: implications for tracking wildlife and forensic science.

Science.gov (United States)

Flockhart, D T Tyler; Kyser, T Kurt; Chipley, Don; Miller, Nathan G; Norris, D Ryan

2015-01-01

Strontium isotopes ((87)Sr/(86)Sr) can be useful biological markers for a wide range of forensic science applications, including wildlife tracking. However, one of the main advantages of using (87)Sr/(86)Sr values, that there is no fractionation from geological bedrock sources through the food web, also happens to be a critical assumption that has never been tested experimentally. We test this assumption by measuring (87)Sr/(86)Sr values across three trophic levels in a controlled greenhouse experiment. Adult monarch butterflies were raised on obligate larval host milkweed plants that were, in turn, grown on seven different soil types collected across Canada. We found no significant differences between (87)Sr/(86)Sr values in leachable Sr from soil minerals, organic soil, milkweed leaves, and monarch butterfly wings. Our results suggest that strontium isoscapes developed from (87)Sr/(86)Sr values in bedrock or soil may serve as a reliable biological marker in forensic science for a range of taxa and across large geographic areas.

COH-SR4 reduces body weight, improves glycemic control and prevents hepatic steatosis in high fat diet-induced obese mice.

Directory of Open Access Journals (Sweden)

James Lester Figarola

Full Text Available Obesity is a chronic metabolic disorder caused by imbalance between energy intake and expenditure, and is one of the principal causative factors in the development of metabolic syndrome, diabetes and cancer. COH-SR4 ("SR4" is a novel investigational compound that has anti-cancer and anti-adipogenic properties. In this study, the effects of SR4 on metabolic alterations in high fat diet (HFD-induced obese C57BL/J6 mice were investigated. Oral feeding of SR4 (5 mg/kg body weight. in HFD mice for 6 weeks significantly reduced body weight, prevented hyperlipidemia and improved glycemic control without affecting food intake. These changes were associated with marked decreases in epididymal fat mass, adipocyte hypertrophy, increased plasma adiponectin and reduced leptin levels. SR4 treatment also decreased liver triglycerides, prevented hepatic steatosis, and normalized liver enzymes. Western blots demonstrated increased AMPK activation in liver and adipose tissues of SR4-treated HFD obese mice, while gene analyses by real time PCR showed COH-SR4 significantly suppressed the mRNA expression of lipogenic genes such as sterol regulatory element binding protein-1c (Srebf1, acetyl-Coenzyme A carboxylase (Acaca, peroxisome proliferator-activated receptor gamma (Pparg, fatty acid synthase (Fasn, stearoyl-Coenzyme A desaturase 1 (Scd1, carnitine palmitoyltransferase 1a (Cpt1a and 3-hydroxy-3-methyl-glutaryl-CoA reductase (Hmgcr, as well as gluconeogenic genes phosphoenolpyruvate carboxykinase 1 (Pck1 and glucose-6-phosphatase (G6pc in the liver of obese mice. In vitro, SR4 activates AMPK independent of upstream kinases liver kinase B1 (LKB1 and Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ. Together, these data suggest that SR4, a novel AMPK activator, may be a promising therapeutic compound for treatment of obesity, fatty liver disease, and related metabolic disorders.

Congenital bilateral neuroblastoma (stage IV-S): case report

International Nuclear Information System (INIS)

Lee, Jeong Hee; Lee, Hee Jung; Woo, Seong Ku; Lee, Sang Rak; Kim, Heung Sik

2002-01-01

Congenital neonatal neuroblastoma is not uncommon but bilateral adrenal neuroblastoma is rare, accounting for about ten percent of neuroblastomas in children. We report the US the MR findings of a stage IV-S congenital bilateral neuroblastoma occurring in a one-day-old neonate

Report on nuclear energy in SR Slovenia; Porocilo o uporabi jedrske energije v SR Sloveniji

Energy Technology Data Exchange (ETDEWEB)

NONE

1987-07-01

Currently Yugoslavia has one 632 MWe nuclear power plant (NPP) of PWR design, located at Krsko in the Socialist Republic (SR) of Slovenia. Krsko NPP, which is a two-loop plant, started power operation in 1981. In general, reactor safety activities in the SR of Slovenia are mostly related to upgrading the safety of our Krsko NPP and to developing capabilities for use in future units. This report presents the nuclear safety related legislation and organization of the corresponding regulatory body, and the activities related to nuclear safety of the participating organizations in the SR of Slovenia in 1987.

Anticancer activity of an extract from needles and twigs of Taxus cuspidata and its synergistic effect as a cocktail with 5-fluorouracil

Directory of Open Access Journals (Sweden)

Shang Weihu

2011-12-01

Full Text Available Abstract Background Botanical medicines are increasingly combined with chemotherapeutics as anticancer drug cocktails. This study aimed to assess the chemotherapeutic potential of an extract of Taxus cuspidata (TC needles and twigs produced by artificial cuttage and its co-effects as a cocktail with 5-fluorouracil (5-FU. Methods Components of TC extract were identified by HPLC fingerprinting. Cytotoxicity analysis was performed by MTT assay or ATP assay. Apoptosis studies were analyzed by H & E, PI, TUNEL staining, as well as Annexin V/PI assay. Cell cycle analysis was performed by flow cytometry. 5-FU concentrations in rat plasma were determined by HPLC and the pharmacokinetic parameters were estimated using 3p87 software. Synergistic efficacy was subjected to median effect analysis with the mutually nonexclusive model using Calcusyn1 software. The significance of differences between values was estimated by using a one-way ANOVA. Results TC extract reached inhibition rates of 70-90% in different human cancer cell lines (HL-60, BGC-823, KB, Bel-7402, and HeLa but only 5-7% in normal mouse T/B lymphocytes, demonstrating the broad-spectrum anticancer activity and low toxicity to normal cells of TC extract in vitro. TC extract inhibited cancer cell growth by inducing apoptosis and G2/M cell cycle arrest. Most interestingly, TC extract and 5-FU, combined as a cocktail, synergistically inhibited the growth of cancer cells in vitro, with Combination Index values (CI ranging from 0.90 to 0.26 at different effect levels from IC50 to IC90 in MCF-7 cells, CI ranging from 0.93 to 0.13 for IC40 to IC90 in PC-3M-1E8 cells, and CI TC extract did not affect the pharmacokinetics of 5-FU in rats. Conclusions The combinational use of the TC extract with 5-FU displays strong cytotoxic synergy in cancer cells and low cytotoxicity in normal cells. These findings suggest that this cocktail may have a potential role in cancer treatment.

Sr isotopic tracer study of the Samail ophiolite, Oman

International Nuclear Information System (INIS)

Lanphere, M.A.; Coleman, R.G.; Hopson, C.A.

1981-01-01

We have measured Rb and Sr concentrations and Sr isotopic compositions in 41 whole-rock samples and 12 mineral separates from units of the Samail ophiolite, including peridotite, gabbro, plagiogranite diabase dikes, and gabbro and websterite dikes within the metamorphic peridotite. Ten samples of cummulate gabbro from the Wadir Kadir section and nine samples from the Wadi Khafifah section have mean 87 Sr/ 86 Sr ratios and standard deviations of 0.70314 +- 0.00030 and 0.70306 +- 0.00034, respectively. The dispersion in Sr isotopic composition may reflect real heterogeneities in the magma source region. The average Sr isotopic composition of cumulate gabbro falls in the range of isotopic compositions of modern midocean ridge basalt. The 87 Sr/ 86 Sr ratios of noncumulate gabbro, plagiogranite, and diabase dikes range from 0.7034 to 0.7047, 0.7038 to 0.7046, and 0.7037 to 0.7061, respectively. These higher 87 Sr/ 86 Sr ratios are due to alteration of initial magmatic compositions by hydrothermal exchange with seawater. Mineral separates from dikes that cut harzburgite tectonite have Sr isotopic compositions which agree with that of cumulate gabbro. These data indicate that the cumulate gabbro and the different dikes were derived from partial melting of source regions that had similar long-term histories and chemical compositions

Thermal infrared and microwave absorbing properties of SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/polyaniline nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Hosseini, Seyed Hossein, E-mail: shhosseini@iiau.ac.ir [Department of Chemistry, Faculty of Science, Islamshahr Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Zamani, Parisa [Department of Applied Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Mousavi, S.Y. [Faculty of Passive Defense, Imam Hossein University, Tehran (Iran, Islamic Republic of)

2015-09-25

Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI exhibited electric and electromagnetic properties. • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO{sub 3} was synthesized as IR absorbent and core and then SrFe{sub 12}O{sub 19} as microwave absorbent was prepared on SrTiO{sub 3} via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO{sub 3}/SrFe{sub 12}O{sub 19} nanoparticles via in situ polymerization by multi core–shell structures (SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the Sr

82Sr--82Rb radioisotope generator

International Nuclear Information System (INIS)

Grant, P.M.; Erdal, B.R.; O'Brien, H.A.

1976-01-01

An improved 82 Sr- 82 Rb radioisotope generator system, based upon the complexing ion exchange resin Chelex-100, has been developed. Columns of this material can be easily and rapidly milked, and the Rb-Sr separation factor for a fresh generator was found to be greater than 10 7 . Approximately 80 percent of the 82 Rb present was delivered in a 15-ml volume of aqueous 0.2 M NH 4 Cl solution. After more than 6 liters of eluant had been put through the generator, the Rb-Sr separation factor was still observed to be greater than 10 5 , and no unusual strontium breakthrough behavior was seen in the system over nearly three 82 Sr half lives. 2 claims, no drawings

Autoradiography of 90Sr in developing rats

International Nuclear Information System (INIS)

Olsen, I.; Jonsen, J.

1979-01-01

The distribution patterns of 90 Sr in five littermate, 8-day-old Wistar rats were studied by whole body autoradiography. Rats were killed 15 min, 1, 4, 24, and 72 h after a single intraperitoneal injection of the isotope. Immediately after administration, 90 Sr was distributed throughout most of the soft tissues of the body. The soft tissue deposits had practically disappeared after 4 h. In the hard tissues of the body 90 Sr accumulated up to 24-72 h. Fifteen minutes after injection the uptake of 90 Sr in the enamel of the teeth was highest in the occlusal and incisal regions. 90 Sr gradually accumulated throughout the enamel and after 72 h its distribution in this layer was fairly uniform. Immediately after injection a narrow zone of radioactivity appeared in the dentin near the pulp. This zone broadened with time towards the dentinoenamel junction and included the intire dentin layer 72 h after injection. Initially, the uptake of 90 Sr was higher in the dentin than in the enamel, particularly in the cervical areas of the crown. This difference became less apparent with time. There was good correlation between the uptake in the teeth and bones, supporting the use of teeth as indicators of the 90 Sr body burden. (author)

Determination of 90Sr by liquid scintillation counting

International Nuclear Information System (INIS)

Cerchetti, Maria L.; Aghazarian, V.P.

2006-01-01

99m Tc, the result of the radioactive decay of 99 Mo, is one of the most applied radioisotopes in nuclear medicine and is used in nuclear medicine as a radiopharmaceutical product. It is important to ensure 99 Mo quality in order to fit the 99m Tc quality specifications. The main objective was to obtain a technique for 90 Sr determination in 99 Mo and environmental samples. The purification of 90 Sr is performed by extraction chromatography where crown-ether resin (Sr-Spec, Eichrom) was used. The measurement of the 90 Sr activity is performed by Liquid Scintillation Counting (LSC) using the double windows method. This method permits the 90 Sr determination without waiting until radiochemical equilibrium 90 Sr / 90 Y has been reached. The recovery factor was determined by gamma spectrometry with 85 Sr, and by gravimetry with stable strontium carrier solution. The minimum detectable activity was 0,05 Bq. The recovery factor was the major contribution in the total uncertainty. (author)

Test for the determination of 90Sr in soil

International Nuclear Information System (INIS)

1980-01-01

The standardized method is based on the chemical separation (extraction, precipitation, etc.) of 90 Sr from other fission products. After long-term storage for 90 Sr- 90 Y equilibrium the activity of the sample precipitated in the form of Y(COO) 2 is measured. The Sr yield coefficient is determined by 85 Sr tracer or by gravimetry. The test is applicable for the determination of 90 Sr contamination originating from fallout or from other sources in soil, when the concentration of 90 Sr is higher than 0.2-0.4 Bqg -1 (5-10 pCig -1 ). The error of the method is less than +-2% of the amount of the 90 Sr present. (Sz.J.)

Toward the establishment of standardized in vitro tests for lipid-based formulations, part 3: understanding supersaturation versus precipitation potential during the in vitro digestion of type I, II, IIIA, IIIB and IV lipid-based formulations.

Science.gov (United States)

Williams, Hywel D; Sassene, Philip; Kleberg, Karen; Calderone, Marilyn; Igonin, Annabel; Jule, Eduardo; Vertommen, Jan; Blundell, Ross; Benameur, Hassan; Müllertz, Anette; Pouton, Colin W; Porter, Christopher J H

2013-12-01

Recent studies have shown that digestion of lipid-based formulations (LBFs) can stimulate both supersaturation and precipitation. The current study has evaluated the drug, formulation and dose-dependence of the supersaturation - precipitation balance for a range of LBFs. Type I, II, IIIA/B LBFs containing medium-chain (MC) or long-chain (LC) lipids, and lipid-free Type IV LBF incorporating different doses of fenofibrate or tolfenamic acid were digested in vitro in a simulated intestinal medium. The degree of supersaturation was assessed through comparison of drug concentrations in aqueous digestion phases (APDIGEST) during LBF digestion and the equilibrium drug solubility in the same phases. Increasing fenofibrate or tolfenamic acid drug loads (i.e., dose) had negligible effects on LC LBF performance during digestion, but promoted drug crystallization (confirmed by XRPD) from MC and Type IV LBF. Drug crystallization was only evident in instances when the calculated maximum supersaturation ratio (SR(M)) was >3. This threshold SR(M) value was remarkably consistent across all LBF and was also consistent with previous studies with danazol. The maximum supersaturation ratio (SR(M)) provides an indication of the supersaturation 'pressure' exerted by formulation digestion and is strongly predictive of the likelihood of drug precipitation in vitro. This may also prove effective in discriminating the in vivo performance of LBFs.

Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO{sub 3}){sub n} films by means of metalorganic aerosol deposition

Energy Technology Data Exchange (ETDEWEB)

Jungbauer, M.; Hühn, S.; Moshnyaga, V. [Erstes Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G. [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

2014-12-22

We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO{sub 3}){sub n} (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO{sub 3}(001) substrates by means of a sequential deposition of Sr-O/Ti-O{sub 2} atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO{sub 3}){sub 4} block at the level of 2.4%. This identifies the SrTiO{sub 3} substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy.

Identification and characterization of a dipeptidyl peptidase IV inhibitor from aronia juice

Energy Technology Data Exchange (ETDEWEB)

Kozuka, Miyuki [Department of Health and Nutrition, Faculty of Human Science, Hokkaido Bunkyo University, Eniwa 061-1449 (Japan); Yamane, Takuya, E-mail: t-yamane@pharm.hokudai.ac.jp [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812 (Japan); Nakano, Yoshihisa [Center for Research and Development Bioresources, Research Organization for University-Community Collaborations, Osaka Prefecture University, Sakai, Osaka 599-8570 (Japan); Nakagaki, Takenori [Institute of Food Sciences, Nakagaki Consulting Engineer Co., Ltd, Nishi-ku, Sakai 593-8328 (Japan); Ohkubo, Iwao [Department of Nutrition, School of Nursing and Nutrition, Tenshi College, Higashi-ku, Sapporo 065-0013 (Japan); Ariga, Hiroyoshi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812 (Japan)

2015-09-25

Aronia berries have many potential effects on health, including an antioxidant effect, effect for antimutagenesis, hepatoprotection and cardioprotection, an antidiabetic effect and inhibition of cancer cell proliferation. Previous human studies have shown that aronia juice may be useful for treatment of obesity disorders. In this study, we found that aronia juice has an inhibitory effect against dipeptidyl peptidase IV (DPP IV) (EC 3.4.14.5). DPP IV is a peptidase that cleaves the N-terminal region of incretins such as glucagon-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). Inactivation of incretins by DPP IV induces reduction of insulin secretion. Furthermore, we identified that cyanidin 3, 5-diglucoside as the DPP IV inhibitor in aronia juice. DPP IV was inhibited more strongly by cyanidin 3, 5-diglucoside than by cyanidin and cyanidin 3-glucoside. The results suggest that DPP IV is inhibited by cyanidin 3, 5-diglucoside present in aronia juice. The antidiabetic effect of aronia juice may be mediated through DPP IV inhibition by cyanidin 3, 5-diglucoside. - Highlights: • DPP IV activity is inhibited by aronia juice. • DPP IV inhibitor is cyanidin 3, 5-diglucoside in aronia juice. • DPP IV is inhibited by cyanidin 3, 5-diglucoside more than cyanidin and cyanidin 3-glucoside.

Interplay between HIV Entry and Transportin-SR2 Dependency

Directory of Open Access Journals (Sweden)

Gijsbers Rik

2011-01-01

Full Text Available Abstract Background Transportin-SR2 (TRN-SR2, TNPO3, transportin 3 was previously identified as an interaction partner of human immunodeficiency virus type 1 (HIV-1 integrase and functions as a nuclear import factor of HIV-1. A possible role of capsid in transportin-SR2-mediated nuclear import was recently suggested by the findings that a chimeric HIV virus, carrying the murine leukemia virus (MLV capsid and matrix proteins, displayed a transportin-SR2 independent phenotype, and that the HIV-1 N74D capsid mutant proved insensitive to transportin-SR2 knockdown. Results Our present analysis of viral specificity reveals that TRN-SR2 is not used to the same extent by all lentiviruses. The DNA flap does not determine the TRN-SR2 requirement of HIV-1. We corroborate the TRN-SR2 independent phenotype of the chimeric HIV virus carrying the MLV capsid and matrix proteins. We reanalyzed the HIV-1 N74D capsid mutant in cells transiently or stably depleted of transportin-SR2 and confirm that the N74D capsid mutant is independent of TRN-SR2 when pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G. Remarkably, although somewhat less dependent on TRN-SR2 than wild type virus, the N74D capsid mutant carrying the wild type HIV-1 envelope required TRN-SR2 for efficient replication. By pseudotyping with envelopes that mediate pH-independent viral uptake including HIV-1, measles virus and amphotropic MLV envelopes, we demonstrate that HIV-1 N74D capsid mutant viruses retain partial dependency on TRN-SR2. However, this dependency on TRN-SR2 is lost when the HIV N74D capsid mutant is pseudotyped with envelopes mediating pH-dependent endocytosis, such as the VSV-G and Ebola virus envelopes. Conclusion Here we discover a link between the viral entry of HIV and its interaction with TRN-SR2. Our data confirm the importance of TRN-SR2 in HIV-1 replication and argue for careful interpretation of experiments performed with VSV-G pseudotyped viruses in

Oriented growth of Sr n+1Ti n O3n+1 Ruddlesden-Popper phases in chemical solution deposited thin films

International Nuclear Information System (INIS)

Gutmann, Emanuel; Levin, Alexandr A.; Reibold, Marianne; Mueller, Jan; Paufler, Peter; Meyer, Dirk C.

2006-01-01

Oriented thin films of perovskite-related Sr n +1 Ti n O 3 n +1 Ruddlesden-Popper phases (n=1, 2, 3) were grown on (001) single-crystalline SrTiO 3 substrates. Preparation of the films was carried out by wet chemical deposition from metalorganic Sr-Ti solutions (rich in Sr) and subsequent conversion into the crystalline state by thermal treatment in air atmosphere at a maximum temperature of 700 deg. C. Solutions were prepared by a modified Pechini method. The films were investigated by wide-angle X-ray scattering and high-resolution transmission electron microscopy. The phase content of powders prepared from the dried solutions and annealed under similar conditions differed from that present in the films, i.e. only polycrystalline SrTiO 3 was detected together with oxides of Ti and Sr. - Graphical abstract: Cross-sectional image of an oriented chemical solution deposited thin film obtained by high-resolution transmission electron microscopy. Periodical spacings corresponding to SrTiO 3 substrate (right) and Sr 2 TiO 4 Ruddlesden-Popper phase (n=1) film region (left) are marked

44/40Ca and 87Sr/86Sr isotopes as tracers of silicate weathering in small catchments of the Massif Central, France

Science.gov (United States)

Négrel, Philippe; Guerrot, Catherine; Millot, Romain; Petelet-Giraud, Emmanuelle; Bullen, Thomas

2013-04-01

We present calcium stable isotope and strontium radiogenic isotope data for soils and sediments developed on volcanic and igneous rocks forming small catchments in the Massif Central (France). Measurements of 44/40Ca isotope ratios (44/40Ca measured by the double spike method on TIMS and normalized to the value for seawater Ca in delta units) in rocks, sediments and soils from silicate catchments (e.g. granite and basalts) together with 87Sr/86Sr isotope ratios permit an examination of the relationships of these isotope systematics during weathering of silicate rocks. We have analysed the granite, weathered granite (arene) and saprolite, sediment and soil overlying the granite on one hand and the basanite, sediment and soil overlying the basanite on the other. The main bedrock in the volcanic zone (e.g. Allanche catchment) is 11 to 2.5 Ma basanite (nephelinitic to leucitic basalts) having SiO2 between 41-45 wt. %, Na2O + K2O bank have 87Sr/86Sr ratios greater than that of the arene with values increasing in the sediment from the surface down to soil. The 87Sr/86Sr vs. Rb/Sr variation observed in the volcanic area likewise confirms the weathering of low 87Sr/86Sr, low Rb/Sr phases in the bedrock, and there is a linear increase in 87Sr/86Sr and Rb/Sr ratios from those in the sediment up to the values observed in the soils. In the volcanic area, the basanite bedrock has 44/40Ca = -0.94 ± 0.05‰ (n = 7), while the soils and sediments have 44/40Ca of -0.75 to -1.13‰ and -0.79 to -1.01‰, respectively. These results suggest that Ca isotopes are not strongly fractionated during weathering of the basalt. The granite whole-rock has 44/40Ca of -1.29‰, while the soil and sediments have 44/40Ca of -1.93 to -2.07‰ and -1.98 to -2.81‰, respectively, with values decreasing as the Ca content decreases. The 44/40Ca ratios of arene, soil and sediment are similar to or less than that of K- feldspar, reflecting complete loss of the relatively heavy Ca from plagioclase and

Reaction of a (Salen)ruthenium(VI) nitrido complex with thiols. C-H bond activation by (Salen)ruthenium(IV) sulfilamido species.

Science.gov (United States)

Man, Wai-Lun; Lam, William W Y; Kwong, Hoi-Ki; Peng, Shie-Ming; Wong, Wing-Tak; Lau, Tai-Chu

2010-01-04

The reaction of [Ru(VI)(N)(L)(MeOH)](PF(6)) [1; L = N,N'-bis(salicylidene)-o-cyclohexyldiamine dianion] with a stoichiometric amount of RSH in CH(3)CN gives the corresponding (salen)ruthenium(IV) sulfilamido species [Ru(IV){N(H)SR}(L)(NCCH(3))](PF(6)) (2a, R = (t)Bu; 2b, R = Ph). Metathesis of 2a with NaN(3) in methanol affords [Ru(IV){N(H)S(t)Bu}(L)(N(3))] (2c). 2a undergoes further reaction with 1 equiv of RSH to afford a (salen)ruthenium(III) sulfilamine species, [Ru(III){N(H)(2)S(t)Bu}(L)(NCCH(3))](PF(6)) (3). On the other hand, 2b reacts with 2 equiv of PhSH to give a (salen)ruthenium(III) ammine species [Ru(III)(NH(3))(L)(NCCH(3))](PF(6)) (4); this species can also be prepared by treatment of 1 with 3 equiv of PhSH. The X-ray structures of 2c and 4 have been determined. Kinetic studies of the reaction of 1 with excess RSH indicate the following schemes: 1 --> 2a --> 3 (R = (t)Bu), 1 --> 2b --> 4 (R = Ph). The conversion of 1 to 2 probably involves nucleophilic attack of RSH at the nitrido ligand, followed by a proton shift. The conversions of 2a to 3 and 2b to 4 are proposed to involve rate-limiting H-atom abstraction from RSH by 2a or 2b. 2a and 2b are also able to abstract H atoms from hydrocarbons with weak C-H bonds. These reactions occur with large deuterium isotope effects; the kinetic isotope effect values for the oxidation of 9,10-dihydroanthracene, 1,4-cyclohexadiene, and fluorene by 2a are 51, 56, and 11, respectively.

β-Adrenergic induced SR Ca2+ leak is mediated by an Epac-NOS pathway.

Science.gov (United States)

Pereira, Laëtitia; Bare, Dan J; Galice, Samuel; Shannon, Thomas R; Bers, Donald M

2017-07-01

Cardiac β-adrenergic receptors (β-AR) and Ca 2+ -Calmodulin dependent protein kinase (CaMKII) regulate both physiological and pathophysiological Ca 2+ signaling. Elevated diastolic Ca 2+ leak from the sarcoplasmic reticulum (SR) contributes to contractile dysfunction in heart failure and to arrhythmogenesis. β-AR activation is known to increase SR Ca 2+ leak via CaMKII-dependent phosphorylation of the ryanodine receptor. Two independent and reportedly parallel pathways have been implicated in this β-AR-CaMKII cascade, one involving exchange protein directly activated by cAMP (Epac2) and another involving nitric oxide synthase 1 (NOS1). Here we tested whether Epac and NOS function in a single series pathway to increase β-AR induced and CaMKII-dependent SR Ca 2+ leak. Leak was measured as both Ca 2+ spark frequency and tetracaine-induced shifts in SR Ca 2+ , in mouse and rabbit ventricular myocytes. Direct Epac activation by 8-CPT (8-(4-chlorophenylthio)-2'-O-methyl-cAMP) mimicked β-AR-induced SR Ca 2+ leak, and both were blocked by NOS inhibition. The same was true for myocyte CaMKII activation (assessed via a FRET-based reporter) and ryanodine receptor phosphorylation. Inhibitor and phosphorylation studies also implicated phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) downstream of Epac and above NOS activation in this pathway. We conclude that these two independently characterized parallel pathways function mainly via a single series arrangement (β-AR-cAMP-Epac-PI3K-Akt-NOS1-CaMKII) to mediate increased SR Ca 2+ leak. Thus, for β-AR activation the cAMP-PKA branch effects inotropy and lusitropy (by effects on Ca 2+ current and SR Ca 2+ -ATPase), this cAMP-Epac-NOS pathway increases pathological diastolic SR Ca 2+ leak. This pathway distinction may allow novel SR Ca 2+ leak therapeutic targeting in treatment of arrhythmias in heart failure that spare the inotropic and lusitropic effects of the PKA branch. Copyright © 2017 Elsevier Ltd. All

A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold.

Science.gov (United States)

Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

2011-07-08

We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2+, Sr2+ and PO4(3-) ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2+, Sr2+ and PO4(3-) ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

Nonablative Fractional Laser Resurfacing for Acne Scarring in Patients With Fitzpatrick Skin Phototypes IV-VI.

Science.gov (United States)

Alexis, Andrew F; Coley, Marcelyn K; Nijhawan, Rajiv I; Luke, Janiene D; Shah, Sejal K; Argobi, Yahya A; Nodzenski, Michael; Veledar, Emir; Alam, Murad

2016-03-01

There is a paucity of studies investigating laser resurfacing in Fitzpatrick skin phototypes (SPT) IV to VI. To assess the efficacy and safety of fractional nonablative laser resurfacing in the treatment of acne scarring in patients with SPT IV to VI. The authors conducted a randomized, investigator-blinded and rater-blinded, split-face comparative study of adults with SPT IV to VI and facial acne scars treated with 2 different density settings and the same fluence. Quantitative global scarring grading system (QGSGS) scores were significantly improved from baseline at 16 and 24 weeks (p = .0277). Improvements in QGSGS scores after higher and lower density treatments were statistically similar (p = .96). The live-blinded dermatologist, the blinded dermatologist photoraters, and the patients rated scars as being significantly more improved by visual analog scale at weeks 16 and 24 compared with baseline (p skin types IV to VI. Self-limited postinflammatory hyperpigmentation was a common occurrence, especially with higher treatment densities.

In situ Sr/Sr investigation of igneous apatites and carbonates using laser-ablation MC-ICP-MS

DEFF Research Database (Denmark)

Bizzarro, Martin; Simonetti, A.; Stevenson, R.K.

2003-01-01

In situ Sr isotopic compositions of coexisting apatite and carbonate for carbonatites from the Sarfartoq alkaline complex, Greenland, have been determined by laser-ablation multicollector inductively coupled plasma mass spectrometry. This study is the first to examine the extent of Sr isotopic ho...

Hybrid HF-DFT comparative study of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties

Energy Technology Data Exchange (ETDEWEB)

Evarestov, R.A.; Bandura, A.V.; Alexandrov, V.E. [Department of Quantum Chemistry, St. Petersburg State University, 26 Universitetskii Prospekt, Stary Petergof, 198504 St. Petersburg (Russian Federation)

2006-10-15

Hybrid HF-DFT LCAO simulations of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties are performed in a single-slab model framework. The SrZrO{sub 3}(001) surface was studied by an ab initio method for the first time. Three slab models with different surface terminations including up to 8 atomic planes were used for calculation of the various surface characteristics (surface energies, atomic charges, density of electronic states). The dependence of the results on the chosen model and on the kind of d-element is analyzed. The dissimilarity in the surface oxygen atom contributions to the total density of states of two crystals is attributed to the more ionic nature of Zr-O bonds compared to Ti-O bonds. It is found that in the case of SrZrO{sub 3} the electronic density is biased towards the SrO-terminated surface and this surface should be more basic in nature than the SrO surface of SrTiO{sub 3} crystal. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Evaluation of improved techniques for the removal of 90Sr and 137Cs from process wastewater and groundwater: Chabazite zeolite baseline study

International Nuclear Information System (INIS)

Bostick, D.T.; Arnold, W.D. Jr.; Taylor, P.A.; McTaggart, D.R.; Burgess, M.W.; Guo, B.

1995-04-01

Standard waste treatment procedures for the removal of 90 Sr and 137 Cs from contaminated groundwater and process wastewaters generate large volumes of secondary contaminated wastes. Several new sorbent materials, ion exchangers, and other processes hold the promise of treating large volumes of contaminated water while minimizing the generation of secondary low-level radioactive wastes. As part of the Efficient Separations/Processes-Integrated Program (ESPIP), these new treatment techniques will be compared with standard processes to define their effectiveness for the removal of radioactive strontium (Sr) and cesium (Cs), as well as to gauge the quantity of secondary radioactive waste generated by the new processes. This report summarizes the efforts made to design standardized testing procedures to evaluate the sorption characteristics of a baseline wastewater treatment technique. Definition of the experimental procedures, as well as a summary of the benchmark sorption technique, will provide the framework with which to compare newly evolving treatment technologies. Accomplishments include selecting the feed strewn to the Process Waste Treatment Plant (PWTP) at Oak Ridge National Laboratory as representative of the prototypical contaminated wastewater of many DOE sites. Samples from the PWTP feed stream were collected and analyzed for metals, anions, total Sr and Cs, radioactive Sr and Cs, alkalinity, pH, and density. The cumulative sample data were used to formulate a simulant that will be used as a standard waste surrogate for comparative testing of selected treatment methods

Synthesis of Ag-loaded SrTiO{sub 3}/TiO{sub 2} heterostructure nanotube arrays for enhanced photocatalytic performances

Energy Technology Data Exchange (ETDEWEB)

Hu, Zijun; Chen, Da; Zhan, Xiaqiang; Wang, Fang; Qin, Laishun; Huang, Yuexiang [China Jiliang University, College of Materials Science and Engineering, Hangzhou, Zhejiang (China)

2017-06-15

In this work, the effect of loading Ag nanoparticles on the photocatalytic activity of SrTiO{sub 3}/TiO{sub 2} nanotube arrays (TNTAs) was investigated. TNTAs were partially transformed to SrTiO{sub 3} through a hydrothermal treatment, which could preserve the tubular structure of TNTAs, and then, Ag nanoparticles were well deposited on the surface of SrTiO{sub 3}/TNTAs heterostructure by a chemical reduction process. Compared to the TNTAs sample, the Ag-loaded SrTiO{sub 3}/TNTAs sample showed significantly enhanced photocatalytic activities for photodegradation of rhodamine B. The enhanced photocatalytic activity of Ag-loaded SrTiO{sub 3}/TNTAs could be attributed to the increased optical absorption as well as the efficient charge transfer and separation of photogenerated electron-hole pairs induced by the SrTiO{sub 3}/TNTAs heterojunction and the Schottky barrier between metallic Ag and SrTiO{sub 3}/TNTAs. On the basis of the trapping experiments, the possible photocatalytic mechanism was also discussed. (orig.)

Effect of prolonged photopeiod on morphology, biomass accumulation and nutrient utilazation and nutrient utilization in post-transplant taxus cuspidata seedlings

International Nuclear Information System (INIS)

Zhao, Y.; Wang, Zi.; Wei, H.; Bao, Y.; Guo, P.

2017-01-01

Both threats and interest are the reasons for studying conservation and restoration programs of yew species. The seedling growth rate of slowly-growing species has been found to accelerate under prolonged photoperiod relative to that under the natural one, but the illumination effect has rarely been identified on yew species especially at their post-transplant stage. In the present study, one-year-old Taxus cuspidata seedlings were fed with exponential fertilization at the rate of 80 mg N/seedling under the prolonged photoperiod (18 h per day) with natural photoperiod (10.5 h per day) as the control in Northeast China. In the subsequent spring, seedlings were sampled to identify their post-transplant responses. Compared to the natural photoperiod, prolonged photoperiod increased seedling height, RCD, root length, and number of FOLR by 70 percent (p<0.0001), 30 percent (p=0.0037), 31 percent (p=0.0128), and 76 percent (P=0.0002), respectively. In addition, prolonged photoperiod increased dry mass in new shoot, old shoot, and root by 140 percent, 200 percent, and 153 percent (all P values <0.0001), respectively. In response to prolonged photoperiod, whole-plant nitrogen (N) and phosphorus (P) contents and utilizaitons decreased with the decline of N concentration in new shoot and P concentration in annual organ, respectively. Our results indicated that prolonged photoperiod did not promote, but stimulated, growth and biomass accumulation of transplanted T. cuspidata seedlings due to inherent decline of nutrient utilization for new growth. (author)

Determination of the electrostatic potential distribution in Pt/Fe:SrTiO₃/Nb:SrTiO₃ thin-film structures by electron holography.

Science.gov (United States)

Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E; Waser, Rainer

2014-11-10

We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

Using noble gases and 87Sr/86Sr to constrain heat sources and fluid evolution at the Los Azufres Geothermal Field, Mexico

Science.gov (United States)

Wen, T.; Pinti, D. L.; Castro, M. C.; Lopez Hernandez, A.; Hall, C. M.; Shouakar-Stash, O.; Sandoval-Medina, F.

2017-12-01

Geothermal wells and hot springs were sampled for noble gases' volume fraction and isotopic measurements and 87Sr/86Sr in the Los Azufres Geothermal Field (LAGF), Mexico, to understand the evolution of fluid circulation following three decades of exploitation and re-injection of used brines. The LAGF, divided into the Southern Production Zone (SPZ) and the Northern Production Zone (NPZ), is hosted in a Miocene to Pliocene andesitic volcanic complex covered by Quaternary rhyolitic-dacitic units. Air contamination corrected 3He/4He ratios (Rc) normalized to the atmospheric ratio (Ra=1.384 x 10-6), show a median value of 6.58 indicating a dominant mantle helium component. Contributions of crustal helium up to 53% and 18% are observed in NPZ and SPZ, respectively. Observations based on Rc/Ra and 87Sr/86Sr ratios points to the mixing of three magmatic sources supplying mantle helium to the LAGF: (1) a pure mantle He (Rc/Ra = 8) and Sr (87Sr/86Sr = 0.7035) source; (2) a pure mantle helium (Rc/Ra = 8) with some radiogenic Sr (87Sr/86Sr = 0.7049) source possibly resulting from Quaternary rhyolitic volcanism; and (3) a fossil mantle He component (Rc/Ra = 3.8) with some radiogenic Sr (87Sr/86Sr = 0.7038), corresponding possibly to the Miocene andesite reservoir. Intrusions within the last 50 kyrs from sources (1) and (2) are likely responsible for the addition of mantle volatiles and heat to the hydrothermal system of Los Azufres. He and Ar isotopes indicate that heat flow is transported by both convection and conduction. Atmospheric noble gas elemental ratios suggest that geothermal wells located closer to the western re-injection zone are beginning to be dominated by re-injection of used brines (injectate). The area affected by boiling in LAGF has further extended to the north and west since the last noble gas sampling campaign in 2009.

Thermodynamic modeling of the Sr-Co-Fe-O system

DEFF Research Database (Denmark)

Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

2016-01-01

This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...... using the CALPHAD approach and was further extrapolated to that of Sr-Co-Fe-O. The thermodynamic database of Sr-Co-Fe-O established in this work allows for calculating phase diagrams, thermodynamic properties, cation distribution and defect chemistry properties, and therefore enables material...

Factors affecting 90Sr uptake from the ration

International Nuclear Information System (INIS)

Knizhnikov, V.A.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

1980-01-01

The dependence of 90 Sr uptake in the human organism on nutrition peculiarities is shown. Strontium-90 polluting vegetable products due to particle sorption from the air is less available for the uptake than 90 Sr resorbed from the soil with vegetation. Therefore, this nuclide is uptaken more completely from milk which containes 90 Sr in a soluble form than from grain and bakery products which are polluted by 90 Sr largely by air

Nonoperative management for patients with grade IV blunt hepatic trauma

Directory of Open Access Journals (Sweden)

Zago Thiago

2012-08-01

Full Text Available Abstract Introduction The treatment of complex liver injuries remains a challenge. Nonoperative treatment for such injuries is increasingly being adopted as the initial management strategy. We reviewed our experience, at a University teaching hospital, in the nonoperative management of grade IV liver injuries with the intent to evaluate failure rates; need for angioembolization and blood transfusions; and in-hospital mortality and complications. Methods This is a retrospective analysis conducted at a single large trauma centre in Brazil. All consecutive, hemodynamically stable, blunt trauma patients with grade IV hepatic injury, between 1996 and 2011, were analyzed. Demographics and baseline characteristics were recorded. Failure of nonoperative management was defined by the need for surgical intervention. Need for angioembolization and transfusions, in-hospital death, and complications were also assessed Results Eighteen patients with grade IV hepatic injury treated nonoperatively during the study period were included. The nonoperative treatment failed in only one patient (5.5% who had refractory abdominal pain. However, no missed injuries and/or worsening of bleeding were observed during the operation. None of the patients died nor need angioembolization. No complications directly related to the liver were observed. Unrelated complications to the liver occurred in three patients (16.7%; one patient developed a tracheal stenosis (secondary to tracheal intubation; one had pleural effusion; and one developed an abscess in the pleural cavity. The hospital length of stay was on average 11.56 days. Conclusions In our experience, nonoperative management of grade IV liver injury for stable blunt trauma patients is associated with high success rates without significant complications.

Nonoperative management for patients with grade IV blunt hepatic trauma.

Science.gov (United States)

Zago, Thiago Messias; Tavares Pereira, Bruno Monteiro; Araujo Calderan, Thiago Rodrigues; Godinho, Mauricio; Nascimento, Bartolomeu; Fraga, Gustavo Pereira

2012-08-22

The treatment of complex liver injuries remains a challenge. Nonoperative treatment for such injuries is increasingly being adopted as the initial management strategy. We reviewed our experience, at a University teaching hospital, in the nonoperative management of grade IV liver injuries with the intent to evaluate failure rates; need for angioembolization and blood transfusions; and in-hospital mortality and complications. This is a retrospective analysis conducted at a single large trauma centre in Brazil. All consecutive, hemodynamically stable, blunt trauma patients with grade IV hepatic injury, between 1996 and 2011, were analyzed. Demographics and baseline characteristics were recorded. Failure of nonoperative management was defined by the need for surgical intervention. Need for angioembolization and transfusions, in-hospital death, and complications were also assessed Eighteen patients with grade IV hepatic injury treated nonoperatively during the study period were included. The nonoperative treatment failed in only one patient (5.5%) who had refractory abdominal pain. However, no missed injuries and/or worsening of bleeding were observed during the operation. None of the patients died nor need angioembolization. No complications directly related to the liver were observed. Unrelated complications to the liver occurred in three patients (16.7%); one patient developed a tracheal stenosis (secondary to tracheal intubation); one had pleural effusion; and one developed an abscess in the pleural cavity. The hospital length of stay was on average 11.56 days. In our experience, nonoperative management of grade IV liver injury for stable blunt trauma patients is associated with high success rates without significant complications.

Decoupling of unpolluted temperate forests from rock nutrient sources revealed by natural 87Sr/86Sr and 84Sr tracer addition

Science.gov (United States)

Kennedy, Martin J.; Hedin, Lars O.; Derry, Louis A.

2002-01-01

An experimental tracer addition of 84Sr to an unpolluted temperate forest site in southern Chile, as well as the natural variation of 87Sr/86Sr within plants and soils, indicates that mechanisms in shallow soil organic horizons are of key importance for retaining and recycling atmospheric cation inputs at scales of decades or less. The dominant tree species Nothofagus nitida feeds nearly exclusively (>90%) on cations of atmospheric origin, despite strong variations in tree size and location in the forest landscape. Our results illustrate that (i) unpolluted temperate forests can become nutritionally decoupled from deeper weathering processes, virtually functioning as atmospherically fed ecosystems, and (ii) base cation turnover times are considerably more rapid than previously recognized in the plant available pool of soil. These results challenge the prevalent paradigm that plants largely feed on rock-derived cations and have important implications for understanding sensitivity of forests to air pollution. PMID:12119394

Adriamycin continuous i.v. infusion for the treatment of childhood hepatic malignancies, toxicity and efficacy: a pilot study childrens cancer study group

International Nuclear Information System (INIS)

Ortega, J.A.; Feusner, J.; Reaman, G.; Woods, W.

1986-01-01

In an effort to increase the number of patients with hepatoblastoma and hepatocellular carcinoma receiving the benefits of complete surgical excision, a pilot study was undertaken at a few Childrens Cancer Study Group institutions. For this purpose, repeated courses of adriamycin administered as a continuous I.V. infusion either singly or in combination with c-platinum and radiation therapy treatment was selected. The patient population consisted of a total of eleven children with primary hepatic malignancies: six children had hepatoblastoma; all six were under two years of age at diagnosis. Five patients with hepatocellular carcinoma were entered to the study. Of the eleven patients, four had previously received adriamycin as an I.V. bolus. A table summarizes the patient's characteristics, the adriamycin dose they received and their responses to therapy

Distribución de Taxus globosa (Taxaceae en México: Modelos ecológicos de nicho, efectos del cambio del uso de suelo y conservación Distribution of Taxus globosa (Taxaceae in Mexico: Ecological niche modeling, effects of land use change and conservation

Directory of Open Access Journals (Sweden)

RAÚL CONTRERAS-MEDINA

2010-01-01

Full Text Available Taxus globosa es una gimnosperma que habita principalmente en los bosques templados de México y el norte de América Central, y que está considerada como amenazada por las agencias de conservación tanto mexicanas como internacionales. En México, una de las mayores amenazas para la mayoría de las especies de los bosques nublados es la pérdida de hábitat, la cual se propicia por la modificación de la cobertura vegetal por factores antropogénicos. Con base en 73 registros de herbario se obtuvo la distribución potencial de la especie mediante el algoritmo Maxent. Asimismo, a partir del modelo obtenido se analizó la modificación de la cobertura vegetal durante tres períodos (1976, 1996 y 2000 y su influencia en la distribución potencial de esta especie. Su distribución potencial fue evaluada en relación con el actual Sistema Nacional de Áreas Naturales Protegidas a nivel federal (ANPs de México y las Regiones Terrestres Prioritarias para la Conservación (RTPs, con el fin de determinar el papel de estas áreas en su conservación y manejo. Los modelos de distribución potencial muestran que existe una reducción importante del área de distribución (hasta el 84 % al existir un cambio de uso de suelo. La especie está mal representada en las ANPs, pues menos del 10 % de su área potencial se encuentra dentro de estas áreas de protección federal. Este tipo de análisis representa una herramienta importante en biogeografía y conservación, así como en otras áreas del quehacer biológico, debido a su habilidad predictiva. Nuestros resultados muestran la urgencia que existe de conservar algunos parches de bosques templados mexicanos (principalmente los bosques nublados para garantizar la existencia de esta especie.Taxus globosa is a gymnosperm inhabiting Mexican and northern Central American temperate forests, and it has been considered as threatened by Mexican and international conservancy agencies. In México, habitat loss is one

Restoration of prostaglandin E2-producing splenic macrophages in 89Sr-treated mice with bone marrow from Corynebacterium parvum primed donors

International Nuclear Information System (INIS)

Shibata, Y.

1989-01-01

Administration of Corynebacterium parvum (CP), 56 mg/kg ip to CBA/J mice effected the induction of prostaglandin E2 (PGE2) producing macrophages (M phi) in the bone marrow and the spleen. Maximal release of PGE2 from M phi cultured in vitro with calcium ionophore A23187 for 2 h was reached by marrow M phi removed on 5 days after CP (450 ng/mg cell protein), and by splenic M phi 9 days after CP (400 ng/mg). Neither M phi population, however, yielded more than 6.0 ng/mg leukotriene C4. To assess ontogenic relationships mice were depleted of bone marrow and blood monocytes by iv injection of the bone-seeking isotope, 89Sr. CP was given at several points before or after bone marrow cell depletion. PGE2 production by splenic M phi harvested on day 9 after CP was profoundly impaired when CP was administered either concurrently with or 3 days after 89Sr. When CP was administered 1, 3, 5, and 7 days before 89Sr, however, the induction of PGE2-producing M phi in the spleen was unaffected. To determine whether bone marrow cells from CP-injected donors can restore PGE2-producing splenic M phi (PGSM) in 89Sr-mice, recipient mice which had and had not received CP 3 days after 89Sr were transfused with 5 x 10(6) syngeneic bone marrow cells from donor mice prepared at varying intervals after CP administration. The results clearly indicate the capacity of bone marrow cells harvested on either day 1 or 2 following CP to restore PGSM in CP-primed, but not unprimed, recipients

Size exclusion chromatography for semipreparative scale separation of Au38(SR)24 and Au40(SR)24 and larger clusters.

Science.gov (United States)

Knoppe, Stefan; Boudon, Julien; Dolamic, Igor; Dass, Amala; Bürgi, Thomas

2011-07-01

Size exclusion chromatography (SEC) on a semipreparative scale (10 mg and more) was used to size-select ultrasmall gold nanoclusters (<2 nm) from polydisperse mixtures. In particular, the ubiquitous byproducts of the etching process toward Au(38)(SR)(24) (SR, thiolate) clusters were separated and gained in high monodispersity (based on mass spectrometry). The isolated fractions were characterized by UV-vis spectroscopy, MALDI mass spectrometry, HPLC, and electron microscopy. Most notably, the separation of Au(38)(SR)(24) and Au(40)(SR)(24) clusters is demonstrated.

Dipeptidyl-peptidase IV (DPP-IV) inhibitor delays tolerance to anxiolytic effect of ethanol and withdrawal-induced anxiety in rats.

Science.gov (United States)

Sharma, Ajaykumar N; Pise, Ashish; Sharma, Jay N; Shukla, Praveen

2015-06-01

Dipeptidyl-peptidase IV (DPP-IV) is an enzyme responsible for the metabolism of endogenous gut-derived hormone, glucagon-like peptide-1 (GLP-1). DPP-IV is known for its role in energy homeostasis and pharmacological blockade of this enzyme is a recently approved clinical strategy for the management of type II diabetes. Accumulating evidences suggest that enzyme DPP-IV can affect spectrum of central nervous system (CNS) functions. However, little is known about the role of this enzyme in ethanol-mediated neurobehavioral complications. The objective of the present study was to examine the impact of DPP-IV inhibitor, sitagliptin on the development of tolerance to anxiolytic effect of ethanol and anxiety associated with ethanol withdrawal in rats. A dose-response study revealed that sitaglitpin (20 mg/kg, p.o.) per se exhibit anxiolytic effect in the elevated plus maze (EPM) test in rats. Tolerance to anxiolytic effect of ethanol (2 g/kg, i.p.; 8 % w/v) was observed from 7(th) day of ethanol-diet (6 % v/v) consumption. In contrast, tolerance to anxiolytic effect of ethanol was delayed in rats that were treated daily with sitagliptin (20 mg/kg, p.o.) as tolerance was observed from 13(th)day since commencement of ethanol-diet consumption. Discontinuation of rats from ethanol-diet after 15-days of ethanol consumption resulted in withdrawal anxiety between 8 h and 12 h post-abstinence. However, rats on 15-day ethanol-diet with concomitant sitagliptin (20 mg/kg, p.o.) treatment exhibited delay in appearance (24 h post-withdrawal) of withdrawal anxiety. In summary, DPP-IV inhibitors may prove as an attractive research strategy against ethanol tolerance and dependence.

Experimental study of suitable methods for measuring the radioactivity of 90Sr during its fast quantitation by extraction with dicarbollides

International Nuclear Information System (INIS)

Svoboda, K.; Kyrs, M.

1994-04-01

The measurement of activity of 90 Sr during its fast isolation by extraction with cobalt dicarbollide and Slovafol 909 in a nitrobenzene-carbon tetrachloride mixed solvent and re-extraction with 0.15 M Chelaton IV at pH 10.2 was investigated. The use of a liquid scintillator allows the effect of the 90 Y beta activity to be eliminated more efficiently than if the evaporation residue is measured with a solid scintillator. Traces of dicarbollide, nitrobenzene and CCl 4 passed into the aqueous solution exert an unfavorable effect by shifting the spectral curve of the 90 Sr+ 90 Y beta radiation towards lower energies, the shift being dependent on the concentration of the above interferents in the aqueous phase. This effect can be eliminated by extracting the aqueous phase with the same volume of octyl alcohol or amyl acetate; while removing the organic interferents, this extraction brings about no apparent loss of strontium. (author). 3 tabs., 7 figs., 5 refs

Thermodynamic modeling of the Sr-Co-Fe-O system

DEFF Research Database (Denmark)

Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

2016-01-01

This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...

Transport properties of LaAlO{sub 3}/SrTiO{sub 3} nanostructures

Energy Technology Data Exchange (ETDEWEB)

Mueller, Alexander; Minhas, Mohsin; Blaschek, Hans-Helmuth [Institut fuer Physik, Martin-Luther-Universitaet Halle-Wittenberg, 06099 Halle (Saale) (Germany); Schmidt, Georg [Institut fuer Physik, Martin-Luther-Universitaet Halle-Wittenberg, 06099 Halle (Saale) (Germany); Interdisziplinaeres Zentrum fuer Materialwissenschaften, Martin-Luther-Universitaet Halle-Wittenberg, 06099 Halle (Saale) (Germany)

2015-07-01

Deposition of thin layers of LaAlO{sub 3} (LAO) on top of a TiO{sub 2} terminated SrTiO{sub 3} (STO) substrate with Pulsed Laser Deposition results in a two dimensional electron gas at the interface. Using PMMA as resist and etch mask this electron gas can be patterned by a standard electron-beam lithography step and subsequent Reactive Ion Etching to remove the LAO. With this process transport structures with minimum dimensions in the sub-micron regime have been fabricated. The structures include gaps of approx. 100 nm width. Transport through the gap is characterized by taking I/V characteristics in a standard four point geometry from room temperature down to 1.5 K. Between 1.5 and 30 K up to a threshold voltage of tens of mV no current is observed. Beyond that threshold voltage the current increases dramatically. Within a few tens of mV the current can increase by up to eight orders of magnitude. The threshold voltage is temperature dependent in a non-monotonic fashion and all I/V curves are free of any hysteresis.

The 87Sr/86Sr aquatic isoscape of the Danube catchment from the source to the mouth as tool for studying fish migrations

Science.gov (United States)

Zitek, Andreas; Tchaikovsky, Anastassiya; Irrgeher, Johanna; Waidbacher, Herwig; Prohaska, Thomas

2014-05-01

Isoscapes - spatially distributed isotope patterns across landscapes - are increasingly used as important basis for ecological studies. The natural variation of the isotopic abundances in a studied area bears the potential to be used as natural tracer for studying e.g. migrations of animals or prey-predator relations. The 87Sr/86Sr ratio is one important tracer, since it is known to provide a direct relation of biological samples to geologically distinct regions, as Sr isotopes are incorporated into living tissues as a proxy for calcium and taken up from the environment without any significant fractionation. Although until now the focus has been mainly set on terrestrial systems, maps for aquatic systems are increasingly being established. Here we present the first 87Sr/86Sr aquatic isoscape of the Danube catchment, the second largest river catchment in Europe, from near its source starting at river km 2581 in Germany down to its mouth to river km 107 in Romania. The total length of the river Danube is 2780 km draining a catchment area 801 463 km2 (10 % of the European continent). The major purpose of this study was to assess the potential of the 87Sr/86Sr isotope ratio to be used as tool for studying fish migrations at different scales in the entire Danube catchment. Within the Joint Danube Research 3 (JDS 3), the biggest scientific multi-disciplinary river expedition of the World in 2013 aiming at the assessment of the ecological status and degree of human alterations along the river Danube, water samples were taken at 68 pre-defined sites along the course of the river Danube including the major tributaries as a basis to create the so called 'Isoscape of the Danube catchment'. The determination of 87Sr/86Sr isotope ratio in river water was performed by multicollector-sector field-inductively coupled plasma-mass spectrometry (MC-SF-ICP-MS). The JDS 3 data were combined with existing data from prior studies conducted within the Austrian part of the Danube catchment

Rapid determination of 90Sr in seawater

International Nuclear Information System (INIS)

Pavlotskaya, F.I.; Moskin, A.I.

1994-01-01

A method for determining 90 Sr in seawater that is based on direct isolation and radiochemical purification of daughter 90 Y is proposed. The analysis time is 6-8 h. The chemical yield of the Y-carrier during the 90 Sr determination from 35 liters of seawater varies in the range 37-69%. The analysis uncertainty is 90 Sr from seawater and subsequent isolation of 90 Y

A study on non-crystalline BiPbSbSrCaCuO and its heat treatment effect

International Nuclear Information System (INIS)

Zhang Hong; Wu Hong; Hu Suhui

1993-01-01

In this work positron annihilation spectroscopy, X ray diffraction, differential thermal analysis, scanning electron microscopy and ac susceptibility measurement have been used to study non-crystalline Bi-Pb-Sb-Sr-Ca-Cu-O and the effect of heat treatment. The crystallization temperature T c is around 450-470 degree C for investigated materials. There are low temperature and high temperature structure relaxation as in metallic glasses from room temperature to glass temperature. For T>T c in the crystallized multiphase the low n phase can transform to high n phase by reaction diffusion and T c can reach near 110 K by 850 degree C annealing. The positron annihilation characteristics are sensitive to phase transformation and the electron density sampled by positrons in the non-crystal is lower than that in crystallized one. The doping of Pb and Sb together is of benefit to forming of non-crystal but narrows the temperature range of the viscous state

Immobilisation of 137Cs and 90Sr in hot-pressed clinoptilolite

International Nuclear Information System (INIS)

Briggs, A.; Jones, D.V.C.; Cole, G.B.; Valentine, T.M.; Preston, R.F.; Hawes, R.W.M.; Fones, M.D.

1984-07-01

It is shown that clinoptilolites from Nevada and Mudhills, California, can be vitrified by hot-pressing at 1000 to 1050 deg C for 30 min under 23 MPa pressure in graphite dies, or for 10 min under 3.5 MPa pressure in stainless steel bellows-shaped containers. Activity measurements before and after hot-pressing show that the radionuclides 137 Cs and 90 Sr are retained almost completely during the process. The hot-pressed material is shown to be extremely resistant to leaching of the nuclides, either in Soxhlet or long-term static leach tests. Gamma-irradiation increases their leachability; that of 90 Sr more than that of 137 Cs, but even so, the leach rates of both remain very low. X-ray diffraction spectra taken before and after heat-treatment for 10 days at temperatures up to 1000 deg C show no deleterious effects, and hydrothermal treatments at temperatures up to 90 deg C for 100 days, even in the presence of sodium ions in solution, are shown not to cause any changes detectable by X-ray diffraction. (author)

PRODUCTION OF PLANTARCIN BY LACTOBACILLUS PLANTARUM SR18

Directory of Open Access Journals (Sweden)

Wagih El-Shouny

2012-06-01

Full Text Available Out of 86 lactobacilli previously screened in our laboratory, Lactobacillus plantarum SR18 isolated from yoghurt revealed the largest detected inhibition zone against the selected indicator Streptococcus salivarius 5. The obtained electrophoretic patterns revealed that L. plantarum SR18 was free from plasmids. Exposure of 6 h growing L. plantarum culture to T-8M, 3B ultraviolet B lamp (8w, 220v & 312 nm for 2 h and subsequent growth for further 24 h resulted in an increase of cell-bound bacteriocin titer reached 2 fold at 12 h. Whereas bacteriocin secreted in the culture filtrate was not affected by UV irradiation. Plantarcin SR18 production was maximal (12800 AU/ml between 12 and 18 h by incubation of the culture at 37°C and pH 5-7 in candle jar (CO2. The bacteriocin bound to the cells and that secreted into the culture filtrate of L. plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. The specific activities (AU/mg protein were increased by a factor of about 5.3 and 2.35 for plantarcins purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and that secreted into the culture filtrate (plantarcin SR18 b, respectively. Gel filtration of plantarcin SR18a resulted in moderate antibacterial activity (3200 AU/ml and very high activity (25600 AU/ml of plantarcin SR18b.

90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

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N. Casacuberta

2013-06-01

Full Text Available The impact of the earthquake and tsunami on the east coast of Japan on 11 March 2011 caused a loss of power at the Fukushima Dai-ichi nuclear power plant (NPP that resulted in one of the most important releases of artificial radioactivity into the environment. Although several works were devoted to evaluating the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr (n = 57 and 89Sr (n = 19 throughout waters 30–600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m−3 and from 19 ± 6 to 265 ± 74 Bq m−3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m−3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidence a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us to establish a 90Sr / 137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e., 0.63 and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

Crystal structures of KM(AsF6)3 (M2+ = Mg, Co, Mn, Zn), KCu(SbF6)3 and [Co(HF)2]Sr[Sr(HF)]2-[Sr(HF)2]2[AsF6]12

International Nuclear Information System (INIS)

Mazej, Zoran; Goreshnik, Evgeny

2015-01-01

The KM(AsF 6 ) 3 (M 2+ = Mg, Co, Mn, Zn) and KCu(SbF 6 ) 3 compounds crystallize isotypically to previously known KNi(AsF 6 ) 3 . The main features of the structure of these compounds are rings of MF 6 octahedra sharing apexes with AsF 6 octahedra connected into infinite tri-dimensional frameworks. In this arrangement cavities are formed where K + cations are placed. Single crystals of CoSr 5 (AsF 6 ) 12 .8HF were obtained as one of the products after the crystallization of 3KF/CoF 2 /SrF 2 mixture in the presence of AsF 5 in anhydrous HF. The CoSr 5 (AsF 6 ) 12 .8HF is monoclinic, C/2c (No.15), with a = 26.773(5) Aa, b = 10.087(2) Aa, c = 21.141(5) Aa, β = 93.296(13) circle , V = 5699.9(19) Aa 3 at 200 K, and Z = 4. There are three crystallographically non-equivalent Sr 2+ cations in the crystal structure of CoSr 5 (AsF 6 ) 12 .8HF. The Sr1 is coordinated by ten fluorine atoms from eight different [AsF 6 ]- anions, meanwhile Sr2 and Sr3 are bound to nine fluorine atoms provided by one HF and eight AsF 6 units or by two HF and six AsF 6 units, respectively. The Co 2+ is coordinated distorted-octahedrally by six fluorine atoms from two HF molecules and four different AsF 6 units. All those moieties in the crystal structure of [Co(HF) 2 ]Sr[Sr(HF)] 2 [Sr(HF) 2 ] 2 [AsF 6 ] 12 are connected into tridimensional framework. The CoSr 5 (AsF 6 ) 12 .8HF is a unique example of compound where HF molecules are directly bound via fluorine atoms to two different metal centres.

Geographical distribution of 90Sr contamination in Poland

International Nuclear Information System (INIS)

Gaca, P.; Mietelski, J.W.; Skwarzec, B.

2006-01-01

The paper presents results on determination of 90 Sr in bilberry and cowberry leaves (Vaccinium myrtillus and Vaccinium vitis-idaea) and the use of these plants as bio-monitors of radiostrontium contamination in Poland. Radiostrontium was determined by mean of liquid scintillation spectrometry preceded by radiochemical separation using Sr-resin and 85 Sr tracer. The approximate map of 90 Sr contamination of Poland is presented. The activity ratio between 90 Sr and obtained earlier data for 137 Cs in the same samples is discussed. The enhancement of radiostrontium content observed in northeastern Poland seems to be the trace of hot-particles fallout from initial Chernobyl cloud, which passed over Polish territory toward Scandinavia. (orig.)

Comparison between IV immune globulin (IVIG) and anti-D globulin for treatment of immune thrombocytopenia: a randomized open-label study.

Science.gov (United States)

Eghbali, Aziz; Azadmanesh, Peyman; Bagheri, Bahador; Taherahmadi, Hasan; Sadeghi Sedeh, Bahman

2016-08-01

To compare the effect of IV immune globulin (IVIG) and anti-D globulin (anti-D) for treatment of immune thrombocytopenia (ITP) in children. A randomized, open-label, single-center clinical trial was carried out in Amir-Kabir Hospital (Arak, Iran). The study was performed on 60 children with acute and chronic ITP, aged from 1 to 15 years. Patients were randomly assigned (1:1) to 50 μg/kg anti-D or 1 g/kg IVIG. Platelet counting was performed at baseline and at 3, 7, and 14 days after treatment termination. Safety assessment was performed in all patients. Anti-D caused a quicker response on the 3rd day of treatment (P anti-D had lower rate of side effects including fever (P anti-D was associated with rapid rise of platelets compared to IVIG. In addition, anti-D treatment had acceptable safety profile. © 2016 Société Française de Pharmacologie et de Thérapeutique.

Contrasting pressure effects in Sr2VFeAsO3 and Sr2ScFePO3

International Nuclear Information System (INIS)

Kotegawa, Hisashi; Kawazoe, Takayuki; Tou, Hideki; Murata, Keizo; Ogino, Hiraku; Kishio, Kohji; Shimoyama, Jun-ichi

2009-01-01

We report the resistivity measurements under pressure of two Fe-based superconductors with a thick perovskite oxide layer, Sr 2 VFeAsO 3 and Sr 2 ScFePO 3 . The superconducting transition temperature T c of Sr 2 VFeAsO 3 markedly increases with increasing pressure. Its onset value, which was T c onset =36.4 K at ambient pressure, increases to T c onset =46.0 K at ∼4 GPa, ensuring the potential of the '21113' system as a high-T c material. However, the superconductivity of Sr 2 ScFePO 3 is strongly suppressed under pressure. The T c onset of ∼16 K decreases to ∼5 K at ∼4 GPa, and the zero-resistance state is almost lost. We discuss the factor that induces this contrasting pressure effect. (author)

Rb-Sr ages and initial 87Sr/86Sr ratios of late paleozoic granitic rocks from northern Chile

International Nuclear Information System (INIS)

Shibata, Ken; Ishihara, Shunso; Ulriksen, C.E.

1984-01-01

Rb-Sr whole-rock isochron ages were determined on three suites of so-called Paleozoic granitic rocks from northern coastal Chile. The granitic rocks from the Valparaiso and Ci Funcho areas are dated as 296.3 +- 5.4 Ma and 262.2 +- 4.6 Ma, respectively, which are in accord with geologically estimated age. The rocks from the Chanaral area is dated as 212.8 +- 8.6 Ma, which is correlated close to the Triassic-Jurassic boundary age. A K-Ar age of 196 +- 6 Ma was obtained on biotite in granite from Esmeralda between Ci Funcho and Chanaral. These age results demonstrate that no Precambrian plutonism occurred in the studied area, and that so-called Paleozoic granitic rocks in the Ci Funcho-Chanaral area are divided into Permian and early Mesozoic in age. Initial 87 Sr/ 86 Sr ratios of the ilmenite-series granitic rocks from the coastal region are 0.70641 (Valparaiso), 0.70635 (Ci Funcho) and 0.70455 (Chanaral). These relatively low ratios deny substantial crustal contribution to the granitoids. The initial ratios of magnetite-series granitoids from porphyry- and manto-type mineralized areas (Chiquicamata, El Salvador and Tocopilla) are as low as 0.70344 to 0.70464. (author)

Sex Reassignment : Predictors and Outcomes Of Treatment for Transsexuals

NARCIS (Netherlands)

Smith, Yolanda Louise Susanne

2002-01-01

Prospective research supports the therapeutic effect of sex reassignment (SR) for adolescent and adult transsexuals. Data were used from 345 patients who applied for SR. Of these applicants, 232 started hormone treatment, 113 did not. The group who completed SR consisted of 196 transsexuals.

Sex Reassignment : Predictors and Outcomes Of Treatment for Transsexuals

OpenAIRE

Smith, Yolanda Louise Susanne

2002-01-01

Prospective research supports the therapeutic effect of sex reassignment (SR) for adolescent and adult transsexuals. Data were used from 345 patients who applied for SR. Of these applicants, 232 started hormone treatment, 113 did not. The group who completed SR consisted of 196 transsexuals. Follow-up data were gathered one to five years after SR. The results of 171 treated adult transsexuals showed improvement in many areas of functioning after SR. The main symptom for which the patients had...

87Sr/86Sr variations in basalts of Late Eocene-Early Miocene series in Eastern Sikhoteh-Alin

International Nuclear Information System (INIS)

Esin, S.V.; Ponomarchuk, V.A.; Shipitsyn, Yu.G.; Palesskij, Yu.G.

1993-01-01

Late Eocene high-alumina and Oligocene high-alumina and magnesian basalts of the Neogene calc-alkaline series from the Eastern Sikhoteh-Alin are shown to have the following 87 Sr/ 86 Sr ratios: 0.70390-0.70465; 0.70347-0.70401, and the 0.70330-0.70347. Analysis of variations of Sr ratios, REE, HFSE, and LILE suggests that they are the products of successive melting of a multicomponent source containing the peridotite material of OIB- and MORB-types altered by fluids to a different degree and the pelagic sediments

Phase equilibria in the system As2-O5 - SrO

International Nuclear Information System (INIS)

Kasenov, B.K.; Ashlyaeva, I.V.

1993-01-01

T-x phase state diagram of As 2 O 5 -SrO system was investigated by the methods of physicochemical analysis. It was established that incongruently melting Sr(AsO 3 ) 2 (t mel 900 deg C), Sr 2 As 2 O 4 (t mel = 1140 deg C), Sr 4 As 2 O 9 (t mel = 1390 deg C) and congruently melting at 1635 deg C Sr 3 (AsO 4 ) 2 formed in the system. Eutectic points were revealed in the system: As 2 O 5 -Sr(AsO 3 ) 2 (15.0 mol % SrO, 700 deg C) and Sr 3 (AsO 4 ) 2 -Sr 4 As 2 O 9 (78 mol % SrO, 1370 deg C)

ACTOplus Met XR in Treating Patients With Stage I-IV Oral Cavity or Oropharynx Cancer Undergoing Definitive Treatment | Division of Cancer Prevention

Science.gov (United States)

This randomized phase IIb trial studies how well ACTOplus met XR works in treating in patients with stage I-IV oral cavity or oropharynx cancer that are undergoing definitive treatment. Chemoprevention is the use of drugs to keep oral cavity or oropharynx cancer from forming or coming back. The use of ACTOplus met XR may slow disease progression in patients with oral cavity or

Luminescent and morphological study of Sr2CeO4 blue phosphor prepared from oxalate precursors

International Nuclear Information System (INIS)

Ferrari, Jefferson L.; Pires, Ana M.; Serra, Osvaldo A.; Davolos, Marian R.

2011-01-01

Luminescent and morphological studies of Sr 2 CeO 4 blue phosphor prepared from cerium-doped strontium oxalate precursor are reported. Powder samples were prepared from 5 and 25 mol% Ce 3+ -doped strontium oxalate as well as from a mechanical mixture of strontium oxalate and cerium oxalate at a 4:1 ratio, respectively. All the samples were characterized by XRD, IR, PLS, and SEM. The luminescent and structural properties of the Sr 2 CeO 4 material are little affected by the SrCO 3 remaining from precursors. The Sr 2 CeO 4 material consists in one-dimensional chains of edge-sharing CeO 6 octahedra that are linked together by Sr 2+ ions. The carbonate ion might be associated with oxygen ions of the linear chain, and also with the oxygen atoms located in the equatorial position, which consequently affects the charge transfer bands between O 2- and Ce 4+ . As observed by SEM, the morphological changes are related to each kind of precursor and thermal treatment, along with irregular powder particles within the size range 0.5-2 μm.

Estimation of Joule heating and its role in nonlinear electrical response of Tb0.5Sr0.5MnO3 single crystal

Science.gov (United States)

Nhalil, Hariharan; Elizabeth, Suja

2016-12-01

Highly non-linear I-V characteristics and apparent colossal electro-resistance were observed in non-charge ordered manganite Tb0.5Sr0.5MnO3 single crystal in low temperature transport measurements. Significant changes were noticed in top surface temperature of the sample as compared to its base while passing current at low temperature. By analyzing these variations, we realize that the change in surface temperature (ΔTsur) is too small to have caused by the strong negative differential resistance. A more accurate estimation of change in the sample temperature was made by back-calculating the sample temperature from the temperature variation of resistance (R-T) data (ΔTcal), which was found to be higher than ΔTsur. This result indicates that there are large thermal gradients across the sample. The experimentally derived ΔTcal is validated with the help of a simple theoretical model and estimation of Joule heating. Pulse measurements realize substantial reduction in Joule heating. With decrease in sample thickness, Joule heating effect is found to be reduced. Our studies reveal that Joule heating plays a major role in the nonlinear electrical response of Tb0.5Sr0.5MnO3. By careful management of the duty cycle and pulse current I-V measurements, Joule heating can be mitigated to a large extent.

Low Thermal Conductivity of RE-Doped SrO(SrTiO3)1 Ruddlesden Popper Phase Bulk Materials Prepared by Molten Salt Method

Science.gov (United States)

Putri, Yulia Eka; Said, Suhana Mohd; Refinel, Refinel; Ohtaki, Michitaka; Syukri, Syukri

2018-04-01

The SrO(SrTiO3)1 (Sr2TiO4) Ruddlesden Popper (RP) phase is a natural superlattice comprising of alternately stacking perovskite-type SrTiO3 layers and rock salt SrO layers along the crystallographic c direction. This paper discusses the properties of the Sr2TiO4 and (La, Sm)-doped Sr2TiO4 RP phase synthesized via molten salt method, within the context of thermoelectric applications. A good thermoelectric material requires high electrical conductivity, high Seebeck coefficient and low thermal conductivity. All three conditions have the potential to be fulfilled by the Sr2TiO4 RP phase, in particular, the superlattice structure allows a higher degree of phonon scattering hence resulting in lowered thermal conductivity. In this work, the Sr2TiO4 RP phase is doped with Sm and La respectively, which allows injection of charge carriers, modification of its electronic structure for improvement of the Seebeck coefficient, and most significantly, reduction of thermal conductivity. The particles with submicron size allows excessive phonon scattering along the boundaries, thus reduces the thermal conductivity by fourfold. In particular, the Sm-doped sample exhibited even lower lattice thermal conductivity, which is believed to be due to the mismatch in the ionic radius of Sr and Sm. This finding is useful as a strategy to reduce thermal conductivity of Sr2TiO4 RP phase materials as thermoelectric candidates, by employing dopants of differing ionic radius.

Verification dosimetry of intravascular 90Sr/90Y source trains

International Nuclear Information System (INIS)

Sharma, S.D.; Shanta, A.; Tripathi, U.B.; Bhatt, B.C.

2001-01-01

90 Sr/ 90 Y source trains (Novoste Beta-Cath System) are currently under clinical trials in India and abroad for intracoronary brachytherapy for prevention of restenosis. Each source train of the Beta-Cath system is supplied with a source certificate giving dose rate at the reference distance of 2 mm from the centerline of the source train. It is essential that the user should check dose rates of brachytherapy sources before its application on the patients. Dose rates and depth dose measurements for 90 Sr/ 90 Y source trains of active length 40 mm using radiochromic films in a tissue equivalent phantom have been carried out. The objectives of these measurements were (1) to verify the dose rates stated in the source certificate, and (2) to obtain relative depth dose data for treatment planning. This paper presents the results of these measurements

Studies on the separation of {sup 89}Sr(II) from irradiated yttria target using 4, 4{sup '}(5{sup '}) di-tert-butyl-cyclohexano-18-crown-6 (DtBuCH18C6) by solvent extraction technique

Energy Technology Data Exchange (ETDEWEB)

Saha, Debasish; Vithya, Jayagopal; Kumar, Ramalingam; Venkata Subramani, Canchipuram Ramamoorthy; Vasudeva Rao, Polur Ranga [Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam (India). Chemistry Group

2016-07-01

The radioisotope {sup 89}Sr as {sup 89}SrCl{sub 2} is medically useful for bone pain palliation and is produced in fast reactors using the {sup 89}Y(n, p){sup 89}Sr reaction. A procedure for isolation of the radionuclide {sup 89}Sr by chemical processing of the irradiated Y{sub 2}O{sub 3} target has been standardised and trial runs have been carried out at the Fast Breeder Test Reactor (FBTR), Kalpakkam. The chemical processing of the irradiated Y{sub 2}O{sub 3} target involves (i) the removal of target Y(III) by TBP extraction and (ii) further purification of the separated {sup 89}Sr fraction by cationic exchange chromatography. However a selective isolation of {sup 89}Sr by the Sr-specific crown ether makes the above chemical processing faster and relatively simple. This work presents a study on the selective removal of Sr from the irradiated target dissolver solution using the Sr-specific crown ether 4,4{sup '}(5{sup '}) di-tert-butyl-cyclohexano-18-crown-6 (DtBuCH18C6) in octanol medium. The separation behaviour of the other impurities such as Ce(IV), Y(III), Tb(III), Eu(III), Zn(II), Mn(II) and Rb(I) present along with Sr(II) in the irradiated sample was also investigated. The method of separation by using the crown ether DtBuCH18C6 is proved to be a potential tool for the purification of {sup 89}Sr(II) source produced from yttria target in fast reactors.

Preparation of highly stable zeolite-alginate foam composite for strontium(90Sr) removal from seawater and evaluation of Sr adsorption performance.

Science.gov (United States)

Hong, Hye-Jin; Kim, Byoung-Gyu; Ryu, Jungho; Park, In-Su; Chung, Kang-Sup; Lee, Sang Moon; Lee, Jin-Bae; Jeong, Hyeon Su; Kim, Hyunchul; Ryu, Taegong

2018-01-01

Alginate bead is a promising strontium (Sr) adsorbent in seawater, but highly concentrated Na ions caused over-swelling and damaged the hydrogel bead. To improve the mechanical stability of alginate bead, flexible foam-type zeolite-alginate composite was synthesized and Sr adsorption performance was evaluated in seawater; 1-10% zeolite immobilized alginate foams were prepared by freeze-dry technique. Immobilization of zeolite into alginate foam converted macro-pores to meso-pores which lead to more compact structure. It resulted in less swollen composite in seawater medium and exhibited highly improved mechanical stability compared with alginate bead. Besides, Sr adsorption efficiency and selectivity were enhanced by immobilization of zeolite in alginate foam due to the increase of Sr binding sites (zeolite). In particular, Sr selectivity against Na was highly improved. The 10% zeolite-alginate foam exhibited a higher log K d of 3.3, while the pure alginate foam exhibited 2.7 in the presence of 0.1 M Na. Finally, in the real seawater, the 10% zeolite-alginate foam exhibited 1.5 times higher Sr adsorption efficiency than the pure alginate foam. This result reveals that zeolite-alginate foam composite is appropriate material for Sr removal in seawater due to its swelling resistance as well as improved Sr adsorption performance in complex media. Copyright © 2017 Elsevier Ltd. All rights reserved.

Geographical traceability based on 87Sr/86Sr indicator: a first approach for PDO Lambrusco wines from Modena.

Science.gov (United States)

Durante, Caterina; Baschieri, Carlo; Bertacchini, Lucia; Cocchi, Marina; Sighinolfi, Simona; Silvestri, Michele; Marchetti, Andrea

2013-12-01

The main goal of this study was to evaluate (87)Sr/(86)Sr ratio in different matrices, namely soils, branches, and grape juices, of an oenological food chain in order to develop a robust analytical strategy able to link the investigated food to its territory of origin. The (87)Sr/(86)Sr has been used as traceability marker and several aspects, affected its variability, i.e. geological features of the investigated area, the bio-available fraction of elements in the soils and the up-take of the plant, have been taken into account. Optimisation of an analytical procedure for the separation of Sr from its interferences and investigation of the analytical performances in terms of precision of used methodology have been carried out as well. This work highlighted a good match between the isotopic values monitored in the bio-available fraction of soils and their respective grape juices for almost all the investigated areas. The correlation with food satisfyingly improves when isotopic relative abundance values of branches vine are considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

FEP report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Skagius, Kristina

2006-11-01

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

AIR: Advances in Respiration - Music therapy in the treatment of chronic pulmonary disease.

Science.gov (United States)

Canga, Bernardo; Azoulay, Ronit; Raskin, Jonathan; Loewy, Joanne

2015-12-01

The aim of this randomized control study is to examine the effect of a multimodal psycho-music therapy intervention on respiratory symptoms, psychological well-being and quality of life of patients with Chronic Obstructive Pulmonary Disease and other lung diseases as adjunct to Pulmonary Rehabilitation with a design of music therapy plus PR compared to Pulmonary Rehabilitation alone. Music therapy group treatment including music visualization, wind playing and singing was provided weekly. This was compared with standard care treatment. Adults ages 48 to 88 (mean 70.1) with moderate to severe GOLD stage II-IV lung disease as well as other diseases processes that lead to chronic airflow limitations were included (n = 98). Participants in both conditions were followed from baseline enrollment to six weeks post control/treatment. Outcome measures included the Beck Depression Inventory Scale 2nd edition-Fast Screen (BDI-FS), Chronic Respiratory Questionnaire Self-Reported (CRQ-SR), and Dyspnea Visual Analog Scale (VAS). Results showed improvement in symptoms of depression (LS mean -0.2) in the music therapy group with statistical divergence between groups (p = 0.007). The CRQ-SR demonstrated improvement in dyspnea (p = 0.01 LS mean 0.5) and mastery (p = 0.06 LS mean 0.5) in the music therapy group and fatigue (p = 0.01 LS mean 0.3). VAS demonstrated highly significant effect in the music therapy group between weeks 5 and 6 (p music therapy combined with standard PR may prove to be an effective modality in the management of pulmonary disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of secondary apatite on the initial 87Sr/86Sr ratio determination in granitic rocks: a case study of the Tadamigawa pluton, northeastern Japan

Science.gov (United States)

Wakasugi, Y.; Ichino, K.; Tanioka, Y.; Wakaki, S.; Tsuboi, M.; Ishikawa, T.

2017-12-01

Apatite is a major accessory mineral in igneous rocks. Because Rb contents in apatite are very low, 87Sr/86Sr ratios of magmatic apatite are useful to estimate the initial 87Sr/86Sr ratio (SrI) of igneous rocks. Secondary post-magmatic event such as hydrothermal alteration may also crystallize secondary apatite, which may inhibit the estimation of SrI of igneous rocks. In this study, we examine the effects of secondary apatite on the initial 87Sr/86Sr ratio determination of granitic rocks by using acid leaching technique. Leached apatite samples were first separated from the whole rock powder as a heavy mineral fraction by heavy liquid technique, and the heavy mineral fraction was then leached by 3 M HNO3. The isotopic ratios of Sr and the concentrations of Rb and Sr were analyzed by TIMS and ICP-MS at Kochi Core Center, respectively. The Tadamigawa Older-stage granites, which locate in the Taishaku Mountains at the northeastern part of Japan, intrude into the Ashio Jurassic complex, and the ages of these rocks are late Cretaceous to Paleogene. The U-Pb ages of zircon and the K-Ar ages of biotite for these rocks are c. 100 Ma [1, 2]. Rb-Sr whole-rock isochron age of the pluton is 96.5 ± 1.3 Ma (SrI = 0.70534 ± 0.00003) and it is concordant with other radiometric ages. Rb-Sr mineral isochron ages range from 84.4 to 97.3 Ma and these ages are relatively younger than the Rb-Sr whole-rock isochron age. The difference among radiometric ages may reflect the difference of the closure temperature in each isotopic system. The Tadamigawa Older-stage granites have SrI for Rb-Sr mineral isochron range from 0.7053 to 0.7061 and are very similar to that (0.70534) for Rb-Sr whole-rock isochron. These may suggest that the Tadamigawa Older-stage granites are generated from same parental magma. However, 87Sr/86Sr ratios of the leached apatite samples were 0.70544-0.70856 and are relatively higher than SrI obtained from the Rb-Sr mineral isochrons (0.7053-0.7061). This result

A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold

Energy Technology Data Exchange (ETDEWEB)

Han Yong; Zhou Jianhong; Zhang Lan; Xu Kewei, E-mail: yonghan@mail.xjtu.edu.cn [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China)

2011-07-08

We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca{sup 2+}, Sr{sup 2+} and PO{sub 4}{sup 3-} ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca{sub 0.5}Sr{sub 0.5}TiO{sub 3} pre-formed on the TiO{sub 2} and grow in length to nanofibers at the expense of Ca{sup 2+}, Sr{sup 2+} and PO{sub 4}{sup 3-} ions that migrate from the TiO{sub 2}. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

A method for determination of 90Sr in vegetation

International Nuclear Information System (INIS)

Nygren, U.

1998-12-01

This report describes a method for determination of 90 Sr in vegetation. The method consists of wet-ashing the samples and separating Sr from the sample matrix by oxalate precipitation and extraction chromatography. 90 Y ingrowth is awaited after which Y is separated from Sr and 90 Y measured in a proportional counter. The method has been applied on two reference materials and the 90 Sr results agree well with the recommended values. The method has also been used on 20 samples of blueberry twigs and the mean recovery of Sr was 74%

Migration and distribution of 90Sr in soil

International Nuclear Information System (INIS)

Yang Juncheng; Zhu Yongyi; Chen Jingjian

1993-01-01

The migration and distribution of radionuclide 90 Sr were conducted by the analysis of 97 soil longitudinal sections under natural conditions and by pot experiments with fallout and 90 Sr solution, respectively. Spring wheat and rice were employed in the pot experiments. The result showed that the radionuclide 90 Sr was mainly accumulated in the topsoil 0-10 cm under both of the natural and laboratory conditions. The vertical distribution of 90 Sr in soil agreed with the power function, which obtained was Y = 75.78 X -0.527 ; r = -0.986; n = 97. The existing forms of 90 Sr from fallout in soil, only 0.02-0.03% was in a soluble form and 0.06-0.07% in non-replaceable form

OpenNebula KVM SR-IOV driver

CSIR Research Space (South Africa)

Macleod, D

2013-05-01

Full Text Available With the recent release of an OFED which supports SR-IOV on Infiniband HCAs it is now possible to use verbs from inside a VM. This VMM driver supports these Infiniband HCAs, and any other SR-IOV network device, in OpenNebula....

Melt processing of Bi-Ca-Sr-Cu-O superconductors

International Nuclear Information System (INIS)

Zanotto, E.D.; Cronin, J.P.; Dutta, B.

1988-01-01

Several Bi-Ca-Sr-Cu-O compositions were melted in Al/sub 2/O/sub 3/ or Pt crucibles at temperatures between 1050C and 1200C. As-quenched specimens crystallized from the upper surfaces, while the bottom layers were glassy. Glass formation was improved for higher Bi/sub 2/O/sub 3/ concentrations. The crystalline portions were highly conductive, while the glassy layers were insulating. Both did not show superconductivity down to 10K. Thermal treatment in air caused a dramatic effect on the electronic properties; and annealing at 865C for long periods converted the two types of specimens (previously glassy or crystalline) to superconductors, at least for one composition. Aluminum impurity (up to 8.6 atom. pct.) had no detectable effect on the transition temperatures, i.e., T/sub c/ 85K for all superconducting samples. The flake-like (Bi/sub 2/Ca/sub 1/Sr/sub 2/Cu/sub 2/) phase, reported by other authors, was responsible for superconductivity

Abscisic Acid (ABA) Regulation of Arabidopsis SR Protein Gene Expression

Science.gov (United States)

Cruz, Tiago M. D.; Carvalho, Raquel F.; Richardson, Dale N.; Duque, Paula

2014-01-01

Serine/arginine-rich (SR) proteins are major modulators of alternative splicing, a key generator of proteomic diversity and flexible means of regulating gene expression likely to be crucial in plant environmental responses. Indeed, mounting evidence implicates splicing factors in signal transduction of the abscisic acid (ABA) phytohormone, which plays pivotal roles in the response to various abiotic stresses. Using real-time RT-qPCR, we analyzed total steady-state transcript levels of the 18 SR and two SR-like genes from Arabidopsis thaliana in seedlings treated with ABA and in genetic backgrounds with altered expression of the ABA-biosynthesis ABA2 and the ABA-signaling ABI1 and ABI4 genes. We also searched for ABA-responsive cis elements in the upstream regions of the 20 genes. We found that members of the plant-specific SC35-Like (SCL) Arabidopsis SR protein subfamily are distinctively responsive to exogenous ABA, while the expression of seven SR and SR-related genes is affected by alterations in key components of the ABA pathway. Finally, despite pervasiveness of established ABA-responsive promoter elements in Arabidopsis SR and SR-like genes, their expression is likely governed by additional, yet unidentified cis-acting elements. Overall, this study pinpoints SR34, SR34b, SCL30a, SCL28, SCL33, RS40, SR45 and SR45a as promising candidates for involvement in ABA-mediated stress responses. PMID:25268622

SR-71 Pilot Stephen (Steve) D. Ishmael

Science.gov (United States)

1992-01-01

NASA research pilot Stephen D. Ishmael is pictured here in front of an SR-71 Blackbird on the ramp at the Dryden Flight Research Center, Edwards, California. Ishmael was one of two NASA research pilots assigned to the SR-71 high speed research program in the early 1990s at NASA's Dryden Flight Research Facility (redesignated the Dryden Flight Research Center in 1994), Edwards, California. Ishmael became a NASA research pilot in 1977. Data from the SR-71 program will be used to aid designers of future supersonic aircraft and propulsion systems. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and

(Ba+Sr)/Ti ratio dependence of the dielectric properties for (Ba0.5Sr0.5)TiO3 thin films prepared by ion beam sputtering

Science.gov (United States)

Yamamichi, Shintaro; Yabuta, Hisato; Sakuma, Toshiyuki; Miyasaka, Yoichi

1994-03-01

(Ba0.5Sr0.5)TiO3 thin films were prepared by ion beam sputtering from powder targets with (Ba+Sr)/Ti ratios ranging from 0.80 to 1.50. All of the perovskite (Ba,Sr)TiO3 films were single phase except for the film with a (Ba+Sr)/Ti ratio of 1.41. The dielectric constant values notably depended on the (Ba+Sr)/Ti ratio for films thicker than 70 nm. The highest dielectric constant of 580 was achieved for the 5% (Ba+Sr) rich film. This (Ba+Sr)/Ti ratio dependence was diminished by the thickness dependence for thinner films. The grain sizes for the 9% (Ba+Sr) rich film and for the 6% (Ba+Sr) poor film ranged from 70 to 100 nm and from 30 to 60 nm, respectively. This grain size difference could explain why slightly A-site rich (Ba,Sr)TiO3 films have a larger dielectric constant than A-site poor films.

Clinical study of 89Sr therapy with radiosensitization by nicotinamide and carbogen in multiple bone metastasis of malignant neoplasms

International Nuclear Information System (INIS)

Liu Yajie; Wang Shubin; Guo Yiling; Chen Zuowei; Zhang Yingnan

2005-01-01

Objective: To evaluate the curative effect and side effects of 89 Sr therapy with radiosensitization by nicotinamide and carbogen in multiple bone metastasis of malignant neoplasms. Methods: Ninety-seven patients were divided into 4 groups respectively: group A, 89 Sr + nicotinamide + carbogen (24 patients); group B, 89 Sr + nicotinamide(22 patients); group C, 89 Sr + carbogen (25 patients); group D, 89 Sr, (26 patients). 89 SrCl was intravenously injected at a dose of 1.48-2.22 MBq/kg. Nicotinamide was taken orally 1 hour before 89 SrCl injection, 6 g/day, tid, d1-d5. Aspiration of carbogen(95%O 2 + 5%CO 2 ) gases, 6 L/min, 10 minutes, qd, d1-d5. Results: The effective rate of pain control and QOL improvement in A group were higher than in groups B, C and D (91.7% VS 77.3%, 76.0% and 69.2%, P=0.048). The lesions assessed by SPECT imaging in every group was not significantly different at three months after treatment. I to II degree toxic effect on bone marrow appeared in every group and there were no significantly inter-group differences. Conclusions: Combinative therapy using 89 Sr + nicotinamide + carbogen is more effective to treat multiple metastatic bone pain and for improvement of QOL. The side effects are not increased. (authors)

The exploration of nursing care for patients with benign prostatic hyperplasia treated using 90Sr-90Y

International Nuclear Information System (INIS)

Xiao Lizhen; Bai Xuemei; Zhang Bihui; Yang Xiaoling

2004-01-01

An exploration of nursing care for patients with benign prostatic hyperplasia (BPH) treated using 90 Sr- 90 Y through the rectum was carried out . The treatment result and nursing experience in 90 cases were reported in this paper. Before the therapy nurses explained the method and principle of this treatment to the patients for the sake of increasing their confidence and to help them complete the treatment course successfully. During the radiotherapy, nurses practiced strictly radiation protection principles and operating instructions. They assisted the patients to have a healthy life style and good diet . The result of treatment indicated that the total effectiveness rate was 96.7%. The symptoms of lower urinary obstruction were improved evidently and the life quality of the patients elevated. Observation of clinical system confirmed that 90 Sr- 90 Y may be a new treatment method of BPH with benefits of safe irradiation dos, easy operation, non-traumatization, painlessness, and remarkable curative effects. However, it should be stressed that nursing care plays a pivotal role in the treatment result. (authors)

Sr and Nd isotope systematics in fish teeth

International Nuclear Information System (INIS)

Staudigel, H.; Zindler, A.

1985-01-01

High concentrations of Sr and Nd in fish teeth apatite (up to 2000 and 3800 ppm, respectively) make them relatively impervious to diagenetic overprints and allow high-precision analysis of 87 Sr/ 86 Sr and 143 Nd/ 144 Nd of very small amounts of material. 87 Sr/ 86 Sr ratios of 14 Cenozoic samples ( 87 Sr/ 86 Sr stratigraphic dating. A compilation of published 143 Nd/ 144 Nd data from recent Mn-nodules and marine Fe/Mn deposits shows that the North-Central Pacific Ocean and the major portion of the Atlantic Ocean display distinctly different, narrow ranges in isotopic compositions. Between these two areas, the 143 Nd/ 144 Nd of Mn-nodules vary systematically towards intermediate compositions in the Southern Oceans, reflecting the communication between the Atlantic and Pacific Oceans through the eastward moving Antarctic Circumpolar Current. The 143 Nd/ 144 Nd of the 2-55 Ma old fish teeth analyzed are typically close to the range of 143 Nd/ 144 Nd in Recent Mn-nodules and seawater for the respective ocean and, thus, indicate no significant change through this time period. The 143 Nd/ 144 Nd of fish teeth from the North Pacific Ocean are highest during periods of high aeolian sedimentation. (orig.)

Spontaneous Carotid-Cavernous Fistula in the Type IV Ehlers-Danlos Syndrome.

Science.gov (United States)

Kim, Jeong Gyun; Cho, Won-Sang; Kang, Hyun-Seung; Kim, Jeong Eun

2014-02-01

Ehlers-Danlos syndrome (EDS) is a rare inherited connective disease. Among several subgroups, type IV EDS is frequently associated with spontaneous catastrophic bleeding from a vascular fragility. We report on a case of carotid-cavernous fistula (CCF) in a patient with type IV EDS. A 46-year-old female presented with an ophthalmoplegia and chemosis in the right eye. Subsequently, seizure and cerebral infarction with micro-bleeds occurred. CCF was completely occluded with transvenous coil embolization without complications. Thereafter, the patient was completely recovered. Transvenous coil embolization can be a good treatment of choice for spontaneous CCF with type IV EDS. However, every caution should be kept during invasive procedure.

Tracing sediment sources in upstream agricultural catchments: contribution of elemental geochemistry, 87Sr/86Sr ratio and radionuclides measurements

International Nuclear Information System (INIS)

Le-Gall, Marion

2016-01-01

Soil erosion is recognized as one of the main processes of land degradation in agricultural environments. This study develops an original fingerprinting method to examine sediment source contributions in two contrasted agricultural catchments. Several properties were used to trace sediment lithological sources ( 87 Sr/ 86 Sr ratios, elemental concentrations), soil surface and subsurface sources ( 137 Cs) and to quantify their temporal dynamics ( 7 Be, 210 Pb xs ). In the Louroux catchment (24 km 2 , France), representative of drained areas of Northwestern Europe, results showed the dominant contribution of very fine particles (≤2 μm) transiting through the tile drainage system to suspended sediment. Sediment accumulated in the river channel was mainly exported during the two first floods investigated in 2013 whereas the next event was characterized by the transport of sediment eroded from the cultivated soil surface. Mixing models were used, and results indicated that surface sources contributed the majority of sediment deposited in the pond, at the outlet of the catchment. The two lithological sources, discriminated using 87 Sr/ 86 Sr ratios, contributed in similar proportions to downstream pond sediment. In contrast, significant variations were observed since the 1950's. These changes may be related to the progressive implementation of land consolidation schemes within the catchment. Results obtained in the Louroux catchment revealed the potential of 87 Sr/ 86 Sr ratios to trace sediment lithological sources. The methodology was then applied to the larger and steeper Guapore catchment (2000 km 2 , Brazil), exposed to a more erosive climate and characterized by contrasted laterite soils. 87 Sr/ 86 Sr ratios and elements that discriminated the five soil types found in the catchment were incorporated in mixing models. Results showed that the major part of sediment was supplied by soils located in lower catchment parts. This result suggests the higher

Transuranium perrhenates: Np(IV), Pu(IV) and (III), Am (III)

International Nuclear Information System (INIS)

Silvestre, Jean-Paul; Freundlich, William; Pages, Monique

1977-01-01

Synthesis in aqueous solution and by solid state reactions, crystallographical characterization and study of the stability of some transuranium perrhenates: Asup(n+)(ReO 4 - )sub(n) (A=Np(IV), Pu(IV), Pu(III), Am(III) [fr

Generation of Dipeptidyl Peptidase-IV-Inhibiting Peptides from β-Lactoglobulin Secreted by Lactococcus lactis

Directory of Open Access Journals (Sweden)

Suguru Shigemori

2014-01-01

Full Text Available Previous studies showed that hydrolysates of β-lactoglobulin (BLG prepared using gastrointestinal proteases strongly inhibit dipeptidyl peptidase-IV (DPP-IV activity in vitro. In this study, we developed a BLG-secreting Lactococcus lactis strain as a delivery vehicle and in situ expression system. Interestingly, trypsin-digested recombinant BLG from L. lactis inhibited DPP-IV activity, suggesting that BLG-secreting L. lactis may be useful in the treatment of type 2 diabetes mellitus.

Kinetics of distribution of 90Sr in Beijing-white layers

International Nuclear Information System (INIS)

Shang Zhaorong; Xu Shiming; Zhao Wenhu; Hou Lanxin

1993-08-01

The experiment feeding 90 Sr(NO 3 ) 2 in the range of 1.85 x 10 2 to 1.85 x 10 5 Bq/chicken was carried out with 45 Beijing-white layers to observe the regular pattern of absorption and distribution of 90 Sr in organs and tissues. The results are summarized as follows: the uptake rate of 90 Sr by layer through oral feeding is very low. Most part of 90 Sr drains away from body with daily excreta and egg. The accumulation of 90 Sr in the body is low and about 70% is in the bone. About 99% of 90 Sr in egg is concentrated in the eggshell. The order of absorptivity of 90 Sr in tissues is bone>feather>muscle>blood>viscera. The absorption coefficient of 90 Sr in organs and tissues in different stages with different feeding volumes has been calculated

Can children undergoing ophthalmologic examinations under anesthesia be safely anesthetized without using an IV line?

Directory of Open Access Journals (Sweden)

Vigoda M

2011-04-01

Full Text Available Michael M Vigoda, Azeema Latiff, Timothy G Murray, Jacqueline L Tutiven, Audina M Berrocal, Steven GayerBascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USAPurpose: To document that with proper patient and procedure selection, children undergoing general inhalational anesthesia for ophthalmologic exams (with or without photos, ultrasound, laser treatment, peri-ocular injection of chemotherapy, suture removal, and/or replacement of ocular prosthesis can be safely anesthetized without the use of an intravenous (IV line. Children are rarely anesthetized without IV access placement. We performed a retrospective study to determine our incidence of IV access placement during examinations under anesthesia (EUA and the incidence of adverse events that required intraoperative IV access placement.Methods: Data collected from our operating room (OR information system includes but is not limited to diagnosis, anesthesiologist, surgeon, and location of IV catheter (if applicable, patient’s date of birth, actual procedure, and anesthesia/procedure times. We reviewed the OR and anesthetic records of children (>1 month and <10 years who underwent EUAs between January 1, 2003 and May 31, 2009. We determined the percentage of children who were anesthetized without IV access placement, as well as the incidence of any adverse events that required IV access placement, intraoperatively.Results: We analyzed data from 3196 procedures performed during a 77-month period. Patients’ ages ranged from 1 month to 9 years. Overall, 92% of procedures were performed without IV access placement. Procedure duration ranged from 1–39 minutes. Reasons for IV access placement included parental preference for antinausea medication and/or attending preference for IV access placement. No child who underwent anesthesia without an IV line had an intraoperative adverse event requiring insertion of an IV line.Conclusion: Our data suggest that for

Interim FEP report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina (ed.) [Kemakta Konsult AB, Stockholm (Sweden)

2004-08-01

This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

Interim FEP report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Skagius, Kristina

2004-08-01

This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

Role of SrO on the bioactivity behavior of some ternary borate glasses and their glass ceramic derivatives

Science.gov (United States)

Abdelghany, A. M.; Ouis, M. A.; Azooz, M. A.; ElBatal, H. A.; El-Bassyouni, G. T.

2016-01-01

Borate glasses containing SrO substituting both CaO and NaO were prepared and characterized for their bioactivity or bone bonding ability. Glass ceramic derivatives were prepared by thermal heat treatment process. FTIR, XRD and SEM measurements for the prepared glass and glass-ceramics before and after immersion in sodium phosphate solution for one and two weeks were carried out. The appearance of two IR peaks within the range 550-680 cm-1 after immersion in phosphate solution indicates the formation of hydroxyapatite or equivalent Sr phosphate layer. X-ray diffraction data agree with the FTIR spectral analysis. The solubility test was carried out for both glasses and glass ceramics derivatives in the same phosphate solution. The introduction of SrO increases the solubility for both glasses and glass ceramics and this is assumed to be due to the formation of Sr phosphate which is more soluble than calcium phosphate (hydroxyapatite). SEM images reveal varying changes in the surfaces of glass ceramics after immersion according to the SrO content.

Role of SrO on the bioactivity behavior of some ternary borate glasses and their glass ceramic derivatives.

Science.gov (United States)

Abdelghany, A M; Ouis, M A; Azooz, M A; ElBatal, H A; El-Bassyouni, G T

2016-01-05

Borate glasses containing SrO substituting both CaO and NaO were prepared and characterized for their bioactivity or bone bonding ability. Glass ceramic derivatives were prepared by thermal heat treatment process. FTIR, XRD and SEM measurements for the prepared glass and glass-ceramics before and after immersion in sodium phosphate solution for one and two weeks were carried out. The appearance of two IR peaks within the range 550-680cm(-1) after immersion in phosphate solution indicates the formation of hydroxyapatite or equivalent Sr phosphate layer. X-ray diffraction data agree with the FTIR spectral analysis. The solubility test was carried out for both glasses and glass ceramics derivatives in the same phosphate solution. The introduction of SrO increases the solubility for both glasses and glass ceramics and this is assumed to be due to the formation of Sr phosphate which is more soluble than calcium phosphate (hydroxyapatite). SEM images reveal varying changes in the surfaces of glass ceramics after immersion according to the SrO content. Copyright © 2015 Elsevier B.V. All rights reserved.

Igneous Consequence Modeling for the TSPA-SR

International Nuclear Information System (INIS)

McCord, John

2001-01-01

The purpose of this technical report is to develop credible, defendable, substantiated models for the consequences of igneous activity for the TSPA-SR Model. The effort will build on the TSPA-VA and improve the quality of scenarios and depth of the technical basis underlying disruptive events modeling. Computational models for both volcanic eruptive releases (this is an event that results in ash containing waste being ejected from Yucca Mountain) and igneous intrusion groundwater releases (this is an event that reaches the repository level, impacts the waste packages, and produces releases from waste packages damaged by igneous activity) will be included directly in the TSPA calculations as part of the TSPA-SR Model. This Analysis Model Report (AMR) is limited to development of the conceptual models for these two scenarios. The mathematical implementation of these conceptual models will be done within the TSPA-SR Model. Thus, this AMR will not include any model results or sensitivity analyses. Calculation of any doses resulting from igneous releases will also be done within the TSPA-SR model, as will the probabilistic weighting of these doses. Calculation and analysis of the TSPA-SR Model results for igneous disruption are, therefore, outside the scope of this activity. The reason for not running the mathematical models as part of this AMR is that the models are integrated within the TSPA-SR model and, thus, any model simulations and the corresponding results are out of the scope of this AMR. The scope of this work as defined in the development plan (CRWMS M and O 2000j) involves using data that has been extracted from existing sources to design and support the TSPA-SR models for the transport of radionuclides following igneous disruption of the repository. The development plan states ''applications of the code in this analysis will be limited to testing of the code and sensitivity analyses during analysis design.'' In contrast to the development plan, the ASHPLUME

Separation of 90Sr from Purex high level waste and development of a 90Sr-90Y generator

International Nuclear Information System (INIS)

Ramanujam, A.; Dhami, P.S.; Chitnis, R.R.; Achuthan, P.V.; Kannan, R.; Gopalakrishnan, V.; Balu, K.

2000-04-01

90 Y (T 1/2 =64.2 h) finds several applications in nuclear medicine. It is formed from the decay of 90 Sr which has a long half-life of 28.8 years. 90 Sr can be used as a long-lasting source for the production of carrier-free 90 Y. 90 Sr itself is abundantly available in high level waste (HLW) of PUREX origin. The present studies deal with the separation of pure 90 Sr from HLW and the subsequent separation of 90 Y from 90 Sr. Actinides and some of the fission products like lanthanides, zirconium, molybdenum and cesium were first removed from the HLW using methods based on solvent extraction and ion-exchange studied earlier in our laboratory. The resulting waste solution was used as a feed for the present process. The separation of 90 Sr from HLW was based on radiochemical method which involved a repeated scavenging with ferric hydroxide followed by strontium carbonate precipitation. The separation of 90 Y from 90 Sr was achieved by membrane separation technique. A compact generator is developed for this separation using a commercially available polytetrafluoroethylene (PTFE) membrane, impregnated with indigenously synthesised 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17). Generator system overcomes the drawbacks associated with conventional solvent extraction and ion-exchange based generators. The product is in chloride form and is suitable for complexation studies. After gaining an operating experience of ∼3 years in generating carrier-free 90 Y at 2 mCi level for initial studies in radiotherapeutic applications, the process was scaled up for the production of about 12 mCi of 90 Y to be used for animal studies before its application to patients. Radiochemical and chemical purity of the product was critically assayed by radiometry, ICP-AES, etc. The process is amenable for further scaling up. (author)

FEP report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina [Kemakta Konsult AB, Stockholm (Sweden)

2006-11-15

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

2017-12-13

A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

System of Sr(NO sub 2 ) sub 2 -Sr(OH) sub 2 -H sub 2 O at 25 deg C. Sistema Sr(NO sub 2 ) sub 2 -H sub 2 O pri 25 grad C

Energy Technology Data Exchange (ETDEWEB)

Popova, T B; Berdyukova, V A; Khutsistova, F M [Kalmytskij Gosudarstvennyj Univ., Ehlista (USSR) Rostovskij-na-Donu Gosudarstvennyj Univ., Rostov-na-Donu (USSR)

1990-02-01

Sr(NO{sub 2}){sub 2}-Sr(OH){sub 2}-H{sub 2}O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO{sub 2}){sub 2}xSr(OH){sub 2}x8H{sub 2}O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained.

ELNES study of chemical solution deposited SrO(SrTiO3)n Ruddlesden-Popper films: Experiment and simulation

International Nuclear Information System (INIS)

Riedl, T.; Gemming, T.; Weissbach, T.; Seifert, G.; Gutmann, E.; Zschornak, M.; Meyer, D.C.; Gemming, S.

2009-01-01

This article analyzes electron energy-loss near-edge fine structures of the SrO(SrTiO 3 ) n=1 Ruddlesden-Popper system and of the parent compounds SrTiO 3 and SrO by comparison with first principles calculations. For that, the fine structures of chemical solution deposited Ruddlesden-Popper films have been experimentally recorded by means of transmission electron microscopy. Moreover, density of states computations using an all-electron density-functional code have been performed. It is shown that the appearance and shape of the experimental O-K and Ti-L 2,3 fine structure features result from the crystallography-dependent electronic structure of the investigated oxides, which display technologically interesting dielectric as well as lattice-structural properties.

Combustion Synthesis of Sm0.5Sr0.5CoO3-x and La0.6Sr0.4CoO3-x Nanopowders for Solid Oxide Fuel Cell Cathodes

Science.gov (United States)

Bansal, Narottam P.; Zhong, zhimin

2005-01-01

Nanopowders of Sm0.5Sr0.5CoO(3-x) (SSC) and La0.6Sr0.4CoO(3-x) (LSC) compositions, which are being investigated as cathode materials for intermediate temperature solid oxide fuel cells, were synthesized by a solution-combustion method using metal nitrates and glycine as fuel. Development of crystalline phases in the as-synthesized powders after heat treatments at various temperatures was monitored by x-ray diffraction. Perovskite phase in LSC formed more readily than in SSC. Single phase perovskites were obtained after heat treatment of the combustion synthesized LSC and SSC powders at 1000 and 1200 C, respectively. The as-synthesized powders had an average particle size of 12 nm as determined from x-ray line broadening analysis using the Scherrer equation. Average grain size of the powders increased with increase in calcination temperature. Morphological analysis of the powders calcined at various temperatures was done by scanning electron microscopy.

Chemical treatments of soil to decrease radiostrontium leachability

International Nuclear Information System (INIS)

Spalding, B.P.

1980-01-01

The ready leachability of radiostrontium from radioactive waste is one of the most salient problems with shallow-land burial as a disposal method. The continuous leaching of buried waste at the Oak Ridge National Laboratory, for periods up to thirty years, has led to contamination of significant volumes of soil with 90 Sr. The goal of the present investigation was to evaluate methods to effect the in situ fixation or decrease the leachability of 90 Sr from soil. Small columns of three soils, collected from the solid waste disposal areas at ORNL, were labelled with 85 Sr as a convenient tracer for 90 Sr. After this labelling but prior to leaching, the soil columns were percolated with equivalent amounts of sodium salt solutions of hydroxide, fluoride, carbonate, phosphate, silicate, or aluminate. Leaching was then initiated with 0.1 N CaCl 2 (calcium chloride), and fractions of the leachate were analyzed for 85 Sr. The CaCl 2 solution was selected to qualitatively simulate groundwater which contains Ca as the dominant dissolved cation. With two soils which were high in indigenous exchangeable Ca, only 30 to 35% of the 85 Sr could be leached from the carbonate-treated columns. Presumably, the 85 Sr was coprecipitated with the nascent CaCO 3 formed during this treatment. In contrast, greater than 98% of the 85 Sr was readily leached from all untreated soils. Other anions fixed variable but generally less 85 Sr than the carbonate treatment. Thus, sodium carbonate appears to have potential application to immobilize 90 Sr in situ in contaminated soil

The hypoxic cytotoxin SR 4233 increases the effectiveness of radioimmunotherapy in mice with human non-Hodgkin's lymphoma xenografts.

Science.gov (United States)

Wilder, R B; McGann, J K; Sutherland, W R; Waller, E K; Minchinton, A I; Goris, M L; Knox, S J

1994-01-01

To determine if either the hypoxic cell radiosensitizer etanidazole (SR 2508) or the hypoxic cytotoxin SR 4233 could improve the effectiveness of radioimmunotherapy. LC4 (an IgG1 monoclonal antibody directed toward malignant T cells) and MB-1 (an irrelevant isotype-matched control antibody) were injected intraperitoneally into severe combined immunodeficient phenotype mice with human cutaneous T cell lymphoma xenografts in order to determine the distribution of the antibodies in the tumors and normal tissues as a function of time. Computerized-pO2-histography was used to measure the median oxygen tension in the tumors. Tumor-bearing mice were treated with: (a) LC4; (b) 90Y-LC4; (c) 90Y-MB-1; (d) whole body irradiation delivered via an external 137Cs source; (e) etanidazole and 90Y-LC4; (f) SR 4233 and 90Y-LC4; (g) etanidazole; and (h) SR 4233. An additional group of mice received no treatment and served as controls. A tumor growth delay assay was used to assess the effectiveness of the different treatment regimens. LC4 accumulated in the tumors to a significantly greater extent than MB-1 (p LC4 by itself was able to produce a minor decrease in tumor size (control vs. LC4; p = 0.001). 90Y-LC4 produced greater tumor growth delay than LC4 alone (LC4 vs. 90Y-LC4; p = 0.01); however, the Yttrium-90 caused neutropenia and weight loss. The 90Y-labeled tumor-specific and non-specific antibodies both exerted greater tumor growth delay than externally delivered whole body irradiation (p LC4 (90Y-LC4 vs etanidazole and 90Y-LC4, p = 0.13). SR 4233, on the other hand, did enhance the tumor growth delay produced by 90Y-LC4 (90Y-LC4 vs. SR 4233 and 90Y-LC4, p = 0.046). The neutropenia and weight loss caused by 90Y-LC4 were exacerbated slightly (< 10%) by the administration of SR 4233. A first generation hypoxic cytotoxin, SR 4233, was able to enhance the tumor growth delay produced by radioimmunotherapy in severe combined immunodeficient phenotype mice with human cutaneous T cell

Possible two-stage 87Sr evolution in the Stockdale Rhyolite

International Nuclear Information System (INIS)

Compston, W.; McDougall, I.; Wyborn, D.

1982-01-01

The Rb-Sr total-rock data for the Stockdale Rhyolite, of significance for the Palaeozoic time scale, are more scattered about a single-stage isochron than expected from experimental error. Two-stage 87 Sr evolution for several of the samples is explored to explain this, as an alternative to variation in the initial 87 Sr/ 86 Sr which is customarily used in single-stage dating models. The deletion of certain samples having very high Rb/Sr removes most of the excess scatter and leads to an estimate of 430 +- 7 m.y. for the age of extrusion. There is a younger alignment of Rb-Sr data within each sampling site at 412 +- 7 m.y. We suggest that the Stockdale Rhyolite is at least 430 m.y. old, that its original range in Rb/Sr was smaller than now observed, and that it experienced a net loss in Sr during later hydrothermal alteration at ca. 412 m.y. (orig.)

Determination of the electrostatic potential distribution in Pt/Fe:SrTiO3/Nb:SrTiO3 thin-film structures by electron holography

Science.gov (United States)

Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E.; Waser, Rainer

2014-11-01

We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

Assessing Covariation of Holocene Monsoon Intensity and Local Moisture Conditions in Eastern and Southwestern Amazon Basin Using Speleothem δ18O and 87Sr/86Sr Values

Science.gov (United States)

Ward, B. M.; Wong, C. I.; Novello, V. F.; Silva, L.; McGee, D.; Cheng, H.; Wang, X.; Edwards, R. L.; Cruz, F. W., Sr.; Santos, R. V.

2017-12-01

δ18O records from South America offer insight into past variability of the South American Monsoon System (SAMS). Potential, however, for understanding local moisture conditions is limited as precipitation δ18O is strongly influenced by regional climate dynamics. Here we create Holocene speleothem 87Sr/86Sr records at 200-yr resolution using TIMS methods in the Center for Isotope Geochemistry at Boston College to complement existing Holocene δ18O speleothem records and investigate local moisture conditions above caves located in the eastern Amazon Basin (PAR - 4°S, 55°W) and southwestern Brazil (JAR - 21°S, 56°W). Speleothem 87Sr/86Sr variability is interpreted to reflect differences in the extent of water-rock interaction due to differences in infiltration rates under wet and dry conditions. Drier conditions promote longer residence time, enhanced water-rock interaction, and greater evolution of dripwater 87Sr/86Sr values from an initial isotopic signature acquired from the soil to the signature of the cave host rock. PAR speleothem 87Sr/86Sr values range from 0.71024 to 0.71067 and are bracketed by soil (0.71710 to 0.70956) and bedrock (0.70852 to 0.70899) values. JAR speleothem 87Sr/86Sr values range from 0.71216 to 0.71539 and are greater than bedrock values (0.70825 to 0.71219), although some speleothem values exceed the single analysis conducted of the soil isotopic composition (0.71473). JAR speleothem 87Sr/86Sr values increase from the early to mid Holocene, consistent with increase in local moisture availability associated with intensification of the SAMS suggested by decreasing δ18O values in many records from the region. Speleothem 87Sr/86Sr values at JAR decrease from the mid to late Holocene, consistent with an increase in δ18O values at PAR that suggest a decline in monsoon intensity. 87Sr/86Sr variability at JAR, however, is positively correlated with the δ18O record. Preliminary 87Sr/86Sr results from PAR are only broadly consistent with

Coordination and solvent extraction behaviour of oxozirconium(IV), thorium(IV) and dioxouranium(VI)

International Nuclear Information System (INIS)

Dash, K.C.

1989-01-01

The systematic liquid-liquid extraction behaviour of oxozirconium (IV), thorium(IV) and dioxouranium(VI) have been investigated using a number of synthesised and commercial chelating extractants. The synergism or antagonism for these processes in presence of neutral donor ligands have also been identified and the conditions for separation and isolation of pure individual metal ions have been established. The coordination behaviour of oxozirconium(IV), thorium(IV) and dioxouranium(VI) with a large number of mono- and polydentate ligands have been studied. With oxozirconium(IV), invariably always a cyclic, tetranuclear species is obtained, derived from the tetrameric structure of the parent ZrOCl 2 .8H 2 O which is actually (Zr 4 (OH) 8 (H 2 O) 16 )Cl 8 .12H 2 O. No simple, monomeric oxozirconium(IV) complex was obtained. Uranium(VI) and thorium(IV) form a wide variety of complexes of higher coordination numbers and several bi- and trinuclear complexes were also characterised where the two adjacent metal centres are joined to each other by a double hydroxo-bridge. (author). 69 refs., 3 figs., 4 tabs

Can women have children and a career? IV evidence from IVF treatments

NARCIS (Netherlands)

Lundborg, P.; Plug, E.; Rasmussen, A.W.

This paper introduces a new IV strategy based on IVF (in vitro fertilization) induced fertility variation among childless women to estimate the causal effect of having children on their career. For this purpose, we use administrative data on IVF treated women in Denmark. Because observed chances of

Bupropion-SR, sertraline, or venlafaxine-XR after failure of SSRIs for depression.

Science.gov (United States)

Rush, A John; Trivedi, Madhukar H; Wisniewski, Stephen R; Stewart, Jonathan W; Nierenberg, Andrew A; Thase, Michael E; Ritz, Louise; Biggs, Melanie M; Warden, Diane; Luther, James F; Shores-Wilson, Kathy; Niederehe, George; Fava, Maurizio

2006-03-23

After unsuccessful treatment for depression with a selective serotonin-reuptake inhibitor (SSRI), it is not known whether switching to one antidepressant is more effective than switching to another. We randomly assigned 727 adult outpatients with a nonpsychotic major depressive disorder who had no remission of symptoms or could not tolerate the SSRI citalopram to receive one of the following drugs for up to 14 weeks: sustained-release bupropion (239 patients) at a maximal daily dose of 400 mg, sertraline (238 patients) at a maximal daily dose of 200 mg, or extended-release venlafaxine (250 patients) at a maximal daily dose of 375 mg. The study was conducted in 18 primary and 23 psychiatric care settings. The primary outcome was symptom remission, defined by a total score of 7 or less on the 17-item Hamilton Rating Scale for Depression (HRSD-17) at the end of the study. Scores on the Quick Inventory of Depressive Symptomatology - Self Report (QIDS-SR-16), obtained at treatment visits, determined secondary outcomes, including remission (a score of 5 or less at exit) and response (a reduction of 50 percent or more on baseline scores). Remission rates as assessed by the HRSD-17 and the QIDS-SR-16, respectively, were 21.3 percent and 25.5 percent for sustained-release bupropion, 17.6 percent and 26.6 percent for sertraline, and 24.8 percent and 25.0 percent for extended-release venlafaxine. QIDS-SR-16 response rates were 26.1 percent for sustained-release bupropion, 26.7 percent for sertraline, and 28.2 percent for extended-release venlafaxine. These treatments did not differ significantly with respect to outcomes, tolerability, or adverse events. After unsuccessful treatment with an SSRI, approximately one in four patients had a remission of symptoms after switching to another antidepressant. Any one of the medications in the study provided a reasonable second-step choice for patients with depression. (ClinicalTrials.gov number, NCT00021528.). Copyright 2006

Rapid determination of {sup 90}Sr in urine samples using AnaLig Sr-01

Energy Technology Data Exchange (ETDEWEB)

Bilohuscin, J.; Dulanska, S.; Gardonova, V. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

2013-04-16

This work describes the use of IBC's AnaLig Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover strontium from urine samples. This method uses two-stage columns separation consisting of two different commercial products Eichrom's Pre-filter Material and AnaLig Sr-01 column from IBC Advanced Technologies. This method does not involve co-precipitation of strontium as phosphates and oxalates from urine samples. The new rapid method separates strontium-90 with high chemical recovery (authors)

Development of an on-line flow injection Sr/matrix separation method for accurate, high-throughput determination of Sr isotope ratios by multiple collector-inductively coupled plasma-mass spectrometry.

Science.gov (United States)

Galler, Patrick; Limbeck, Andreas; Boulyga, Sergei F; Stingeder, Gerhard; Hirata, Takafumi; Prohaska, Thomas

2007-07-01

This work introduces a newly developed on-line flow injection (FI) Sr/Rb separation method as an alternative to the common, manual Sr/matrix batch separation procedure, since total analysis time is often limited by sample preparation despite the fast rate of data acquisition possible by inductively coupled plasma-mass spectrometers (ICPMS). Separation columns containing approximately 100 muL of Sr-specific resin were used for on-line FI Sr/matrix separation with subsequent determination of (87)Sr/(86)Sr isotope ratios by multiple collector ICPMS. The occurrence of memory effects exhibited by the Sr-specific resin, a major restriction to the repetitive use of this costly material, could successfully be overcome. The method was fully validated by means of certified reference materials. A set of two biological and six geological Sr- and Rb-bearing samples was successfully characterized for its (87)Sr/(86)Sr isotope ratios with precisions of 0.01-0.04% 2 RSD (n = 5-10). Based on our measurements we suggest (87)Sr/(86)Sr isotope ratios of 0.713 15 +/- 0.000 16 (2 SD) and 0.709 31 +/- 0.000 06 (2 SD) for the NIST SRM 1400 bone ash and the NIST SRM 1486 bone meal, respectively. Measured (87)Sr/(86)Sr isotope ratios for five basalt samples are in excellent agreement with published data with deviations from the published value ranging from 0 to 0.03%. A mica sample with a Rb/Sr ratio of approximately 1 was successfully characterized for its (87)Sr/(86)Sr isotope signature to be 0.718 24 +/- 0.000 29 (2 SD) by the proposed method. Synthetic samples with Rb/Sr ratios of up to 10/1 could successfully be measured without significant interferences on mass 87, which would otherwise bias the accuracy and uncertainty of the obtained data.

Effect of Flowing Water on Sr Sorption Changes of Hydrous Sodium Titanate

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Youko Takahatake

2017-12-01

Full Text Available Radioactive contaminated water has been generated at the Fukushima Daiichi Nuclear Power station (F1NPS. Hydrous sodium titanate (SrTreat® is able to remove radioactive Strontium (Sr from this water. Knowing the amount of radioactive nuclides in the used as-received SrTreat® is important for effective disposal and deposition of the F1NPS waste. This study investigated changes in the ability of SrTreat® to sorb Sr, and to understand the causes of changes in the sorbing. An investigation of the Sr sorption ability of SrTreat® is important for calculating the initial radioactive inventory of used SrTreat®. This study carries out Sr sorption studies with acid-base titrations and X-ray photoelectron spectroscopy (XPS to characterize the properties. After exposure to simulated treated water for 99 h, the surface structure of the SrTreat® was changed, and the percentage of sorbed Sr and the buffer capacity for protons decreased. When the amount of radioactive nuclides contained in the used SrTreat® is calculated from the sorption data of the as-received SrTreat®, the radioactive Sr content will be overestimated with a concomitant increase in the deposition and disposal costs of the used SrTreat®.

Evaluation of magnetic- and carbon-based nano-adsorbents application in pre-purification of paclitaxel from needles of Taxus baccata

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Naghavi, M. R., E-mail: mnaghavi@ut.ac.ir; Motamedi, E., E-mail: motamedi.elaheh@gmail.com; Nasiri, J., E-mail: jaber.nasiri@ut.ac.ir; Alizadeh, H., E-mail: halizade@ut.ac.ir [University of Tehran, Division of Molecular Plant Genetics, Department of Agronomy and Plant Breeding, College of Agricultural & Natural Resources (Iran, Islamic Republic of); Fattahi Moghadam, M. R., E-mail: fattahi@ut.ac.ir [University of Tehran, Department of Horticultural Sciences, College of Agricultural & Natural Resources (Iran, Islamic Republic of); Mashouf, A., E-mail: mashouf-alireza@yahoo.com [Shahid Beheshti University, Medicinal Plants and Drugs Research Institute (Iran, Islamic Republic of)

2015-01-15

In this investigation, the proficiency of a number of magnetic carbon-based nano-adsorbents is evaluated in pre-purification process of the crude paclitaxel extract obtained from fresh needles of yew tree (Taxus baccata L.). The effectiveness and removal ability of color and impurities from crude extracts, for three novel candidate nano-adsorbents (i.e., Fe{sub 3}O{sub 4} nanoparticles (Fe{sub 3}O{sub 4}Nps), graphite oxide (GO), and their hybrids Fe{sub 3}O{sub 4}Nps/GO) are compared with commercial graphite in three different solvents. In general, both HPLC and UV–Vis spectroscopy results demonstrate that in less polar solvent (i.e., dichloromethane), the adsorption is greatly affected by the electrostatic attractions, while in more polar solvents (i.e., acetone and ethanol) π–π electron interactions taking place between adsorbent and adsorbate are the most dominant factors in sorption. Considering decolorization efficiency, purity of taxol, recovery and reusability of adsorbents, Fe{sub 3}O{sub 4}Nps/GO (50 g/L) in dichloromethane is selected as the best medium for pre-purification of paclitaxel. Additionally, in kinetic studies the sorption equilibrium can be reached within 120 min, and the experimental data are well fitted by the pseudo-second-order model. The Langmuir sorption isotherm model correlates well with the sorption equilibrium data for the crude extract concentration (500–2,000 mg/L). Our findings display promising applications of Fe{sub 3}O{sub 4}Nps/GO, as a cost-effective nano-adsorbent, to provide a suitable vehicle toward improvement of paclitaxel pre-purification.

The changes of the immunological indexes in the patients with bone metastases treated with 89SrCl2

International Nuclear Information System (INIS)

Li Yong; Fang Na

2004-01-01

Objective: To study the influence of 89 SrCl 2 on the immunological functions in the patients with bone metastases. Methods: Forty-two patients with proved bone metastases were treated with 89 SrCl 2 and according to the final therapeutic efficiency for the metastatic lesions, the patients were divided into efficacious and inefficacious group. Twenty untreated healthy adults served as control group. The T lymphocyte subsets CD 4 + , CD 8 + , CD 4 + /CD 8 + were analyzed before and after 89 SrCl 2 treatment. Results: The immunological indexes were not significantly different between the two patient groups before the therapy of 89 SrCl 2 . The indexes between the controls and patients before and after the therapy were different significantly (P 89 SrCl 2 , 37 (88.10%) patients' immunological functions were improved, 33 patients (78.57%) stated that their pain were effectively relieved, 29 (69.05%) patients' bone metastatic lesions reduced. Conclusions: The immunological functions in the patients with bone metastases were inhibited obviously. Treating with 89 SrCl 2 can improve their immunological functions to a certain extent. The recovery level of the inefficacious patients was lower than that of the efficacious patients. The changes of immunological functions can reflect the therapeutical effectiveness. (authors)

Utilization Patterns of IV Iron and Erythropoiesis Stimulating Agents in Anemic Chronic Kidney Disease Patients: A Multihospital Study

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Avani D. Joshi

2012-01-01

Full Text Available Intravenous (IV iron and Erythropoiesis Stimulating Agents (ESAs are recommended for anemia management in chronic kidney disease (CKD. This retrospective cohort study analyzed utilization patterns of IV iron and ESA in patients over 18 years of age admitted to University Health System Hospitals with a primary or secondary diagnosis of CKD between January 1, 2006 to December 31, 2008. A clustered binomial logistic regression using the GEE methodology was used to identify predictors of IV iron utilization. Only 8% (n = 6678 of CKD patients on ESA therapy received IV iron supplementation in university hospitals. Those receiving iron used significantly less amounts of ESAs. Patient demographics (age, race, primary payer, patient clinical conditions (admission status, severity of illness, dialysis status, and physician specialty were identified as predictors of IV iron use in CKD patients. Use of IV iron with ESAs was low despite recommendations from consensus guidelines. The low treatment rate of IV iron represents a gap in treatment practices and signals an opportunity for healthcare improvement in CKD anemic patients.

Rapid Simultaneous Determination of 89Sr and 90Sr in Milk: A Procedure Using Cerenkov and Scintillation Counting

International Nuclear Information System (INIS)

2013-01-01

Since 2004, the IAEA programme related to the terrestrial environment has included activities aimed at developing and testing a set of procedures for the determination of radionuclides in environmental samples. Both 89Sr and 90Sr are fission products that can be, and have been, released to the environment during nuclear explosions and nuclear reactor accidents. Since strontium uptake from milk is an important pathway for incorporation of radioactive strontium into the human body, the rapid and accurate analysis of radioactive strontium isotopes in milk is of crucial importance in emergency situations in order to protect the public from radiation hazards. This report describes a new approach for the rapid determination of 89 Sr and 90Sr in milk using Cerenkov and scintillation counting methods that was tested and validated by the analysis of four spiked milk samples in terms of repeatability, reproducibility and trueness (relative bias) in accordance with ISO guidelines. The report also describes the calculation of the uncertainty budget. This research was proposed in 2007 at the Asia-Pacific regional meeting of the IAEA Analytical Laboratories for the Measurement of Environmental Radioactivity (ALMERA) network. Several ALMERA network laboratories participated in the validation procedure by performing reproducibility tests. The resulting recommended procedure is designed to be of general use to a wide range of laboratories, including those in the ALMERA network. It is expected that this rapid method for determining 89 Sr and 90 Sr in milk will be useful in emergency conditions and for routine environmental monitoring of elevated levels of radioactivity

Effect of SrO content on Zeolite Structure

Science.gov (United States)

Widiarti, N.; Sari, U. S.; Mahatmanti, F. W.; Harjito; Kurniawan, C.; Prasetyoko, D.; Suprapto

2018-04-01

The aims of current studies is to investigate the effect of strontium oxide content (SrO) on synthesized zeolite. Zeolite was synthesized from Tetraethyl orthosilicate (TEOS) as precursors of SiO2 and aluminum isopropoxide (AIP) precursors. The mixture was aged for 3 days and hydrothermally treated for 6 days. The SrO content was added by impregnation method. The products were then characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), and Surface Area Analyzer (SAA). The diffractogram confirmed the formation of Faujasite-like zeolite. However, after the addition of SrO, the crystallinity of zeolite was deformed. The diffractograms shows the amorphous phase of zeolite were decrease as the SrO content is increase. The structural changes was also observed from FTIR spectra which shows the shifting and peak formation. The surface area analysis showed that the increasing loading of SrO/Zeolites reduced the catalyst surface area.

Spontaneous Carotid-Cavernous Fistula in the Type IV Ehlers-Danlos Syndrome

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Kim, Jeong Gyun; Cho, Won-Sang; Kim, Jeong Eun

2014-01-01

Ehlers-Danlos syndrome (EDS) is a rare inherited connective disease. Among several subgroups, type IV EDS is frequently associated with spontaneous catastrophic bleeding from a vascular fragility. We report on a case of carotid-cavernous fistula (CCF) in a patient with type IV EDS. A 46-year-old female presented with an ophthalmoplegia and chemosis in the right eye. Subsequently, seizure and cerebral infarction with micro-bleeds occurred. CCF was completely occluded with transvenous coil embolization without complications. Thereafter, the patient was completely recovered. Transvenous coil embolization can be a good treatment of choice for spontaneous CCF with type IV EDS. However, every caution should be kept during invasive procedure. PMID:24653803

The complete chloroplast genome sequence of Taxus chinensis var. mairei (Taxaceae): loss of an inverted repeat region and comparative analysis with related species.

Science.gov (United States)

Zhang, Yanzhen; Ma, Ji; Yang, Bingxian; Li, Ruyi; Zhu, Wei; Sun, Lianli; Tian, Jingkui; Zhang, Lin

2014-05-01

Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of T. chinensis var. mairei. The T. chinensis var. mairei cp genome is 129,513 bp in length, with 113 single copy genes and two duplicated genes (trnI-CAU, trnQ-UUG). Among the 113 single copy genes, 9 are intron-containing. Compared to other land plant cp genomes, the T. chinensis var. mairei cp genome has lost one of the large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperm such as Cycas revoluta and Ginkgo biloba L. Compared to related species, the gene order of T. chinensis var. mairei has a large inversion of ~110kb including 91 genes (from rps18 to accD) with gene contents unarranged. Repeat analysis identified 48 direct and 2 inverted repeats 30 bp long or longer with a sequence identity greater than 90%. Repeated short segments were found in genes rps18, rps19 and clpP. Analysis also revealed 22 simple sequence repeat (SSR) loci and almost all are composed of A or T. Copyright © 2014 Elsevier B.V. All rights reserved.

Resistance switching in epitaxial SrCoOx thin films

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Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

2014-08-01

We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO2.5) and conducting perovskite (SrCoO3-δ) depending on the oxygen content. The current-voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoOx thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO2.5.

Resistance switching in epitaxial SrCoOx thin films

International Nuclear Information System (INIS)

Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

2014-01-01

We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO 3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO 2.5 ) and conducting perovskite (SrCoO 3−δ ) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO x thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO 2.5

Trace determination of 90Sr and 89Sr in environmental samples by collinear resonance ionization spectroscopy

International Nuclear Information System (INIS)

Lantzsch, J.; Bushaw, B. A.; Bystrow, V. A.; Herrmann, G.; Kluge, H.-J.; Niess, S.; Otten, E. W.; Passler, G.; Schwalbach, R.; Schwarz, M.; Stenner, J.; Trautmann, N.; Wendt, K.; Yushkevich, Y. V.; Zimmer, K.

1995-01-01

Collinear resonance ionization spectroscopy has been developed as a sensitive technique for fast trace detection of 90 Sr and 89 Sr in the environment. A detection limit for 90 Sr of 10 7 atoms in the presence of 10 17 atoms in the presence of 10 17 atoms of stable Strontium has been achieved, while the applicability of the method has been demonstrated on real world samples. After collection and chemical separation, strontium is surface ionized, accelerated to 33keV and mass separated. The ions are neutralized and the emerging fast atoms interact with an argon ion laser beam (γ=364 nm) in a quasi-collinear geometry. Optical excitation starts from the long-lived 5s4d 3 D2 state of strontium, which is populated in the charge exchange process, and the fast atoms are selectively excited into the high-lying 5s23f 3 F3 Rydberg state. The Rydberg-atoms are subsequently field-ionized and detected by a channeltron detector after energy selection. The described method was successfully used to determine the 90 Sr-content in air samples collected near Munich during the Chernobyl reactor accident in April 1986

Estimating the effect of treatment rate changes when treatment benefits are heterogeneous: antibiotics and otitis media.

Science.gov (United States)

Park, Tae-Ryong; Brooks, John M; Chrischilles, Elizabeth A; Bergus, George

2008-01-01

Contrast methods to assess the health effects of a treatment rate change when treatment benefits are heterogeneous across patients. Antibiotic prescribing for children with otitis media (OM) in Iowa Medicaid is the empirical example. Instrumental variable (IV) and linear probability model (LPM) are used to estimate the effect of antibiotic treatments on cure probabilities for children with OM in Iowa Medicaid. Local area physician supply per capita is the instrument in the IV models. Estimates are contrasted in terms of their ability to make inferences for patients whose treatment choices may be affected by a change in population treatment rates. The instrument was positively related to the probability of being prescribed an antibiotic. LPM estimates showed a positive effect of antibiotics on OM patient cure probability while IV estimates showed no relationship between antibiotics and patient cure probability. Linear probability model estimation yields the average effects of the treatment on patients that were treated. IV estimation yields the average effects for patients whose treatment choices were affected by the instrument. As antibiotic treatment effects are heterogeneous across OM patients, our estimates from these approaches are aligned with clinical evidence and theory. The average estimate for treated patients (higher severity) from the LPM model is greater than estimates for patients whose treatment choices are affected by the instrument (lower severity) from the IV models. Based on our IV estimates it appears that lowering antibiotic use in OM patients in Iowa Medicaid did not result in lost cures.

Fate of stable strontium in the sewage treatment process as an analog for radiostrontium released by nuclear accidents

International Nuclear Information System (INIS)

Kamei-Ishikawa, Nao; Ito, Ayumi; Umita, Teruyuki

2013-01-01