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Sample records for polymethylmethacrylate dosimeter radix

  1. Durable antistatic coating for polymethylmethacrylate

    NASA Technical Reports Server (NTRS)

    Hadek, V.; Somoano, R. B.; Rembaum, A. (Inventor)

    1977-01-01

    A durable antistatic coating is achieved on polymethylmethacrylate plastic without affecting its optical clarity by applying to the surface of the plastic a low molecular weight solvent having a high electron affinity and a high dipole moment, such as acentonitrile or nitromethane alone or in the presence of photopolymerizable monomer. The treated polymethylmethacrylate plastic dissipates most of the induced electrostatic charge and retains its optical clarity. The antistatic behavior persists after washing, rubbing and vacuum treatment.

  2. Radiation dosimeters

    DOEpatents

    Hoelsher, James W.; Hegland, Joel E.; Braunlich, Peter F.; Tetzlaff, Wolfgang

    1992-01-01

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  3. Wristwatch dosimeter

    DOEpatents

    Wolf, M.A.; Waechter, D.A.; Umbarger, C.J.

    1986-08-26

    The disclosure is directed to a wristwatch dosimeter utilizing a CdTe detector, a microprocessor and an audio and/or visual alarm. The dosimeter is entirely housable with a conventional digital watch case having an additional aperture enabling the detector to receive radiation. 10 figs.

  4. Wristwatch dosimeter

    DOEpatents

    Wolf, Michael A.; Waechter, David A.; Umbarger, C. John

    1986-01-01

    The disclosure is directed to a wristwatch dosimeter utilizing a CdTe detector, a microprocessor and an audio and/or visual alarm. The dosimeter is entirely housable with a conventional digital watch case having an additional aperture enabling the detector to receive radiation.

  5. Citizen's dosimeter

    SciTech Connect

    Klemic, Gladys; Bailey, Paul; Breheny, Cecilia

    2008-09-02

    The present invention relates to a citizen's dosimeter. More specifically, the invention relates to a small, portable, personal dosimetry device designed to be used in the wake of a event involving a Radiological Dispersal Device (RDD), Improvised Nuclear Device (IND), or other event resulting in the contamination of large area with radioactive material or where on site personal dosimetry is required. The card sized dosimeter generally comprises: a lower card layer, the lower card body having an inner and outer side; a upper card layer, the layer card having an inner and outer side; an optically stimulated luminescent material (OSLM), wherein the OSLM is sandwiched between the inner side of the lower card layer and the inner side of the upper card layer during dosimeter radiation recording, a shutter means for exposing at least one side of the OSLM for dosimeter readout; and an energy compensation filter attached to the outer sides of the lower and upper card layers.

  6. PERSONNEL DOSIMETER

    DOEpatents

    Birkhoff, R.D.; Hubbell, H.H. Jr.; Johnson, R.M.

    1959-02-24

    A personnel dosimeter sensitive to both gamma and beta radiation is described. The dosimeter consists of an electrical conductive cylinder having a wall thickness of substantially 7 milligrams per square centimeter and an electrode disposed axially within the cylinder and insulated therefrom to maintain a potential impressed between the electrode and the cylinder. A cylindrical perforated shield provided with a known percentage of void area is disposed concentrically about the cylinder. The shield is formed of a material which does not contain more than 15 percent of an element higher than atomic weight 13. The dose actually received is at most the gamma dose plus the beta dose indicated by discharge of the dosimeter divided by the known percentage.

  7. RADIATION DOSIMETER

    DOEpatents

    Balkwell, W.R. Jr.; Adams, G.D. Jr.

    1960-05-10

    An improvement was made in the determination of amounts of ionizing radiation, particularly low-energy beta particles of less than 1000 rad total dose by means of fluid-phase dosimeter employing a stabilized-- sensitized ferrous-ferric colorimetric system in a sulphuric acid medium. The improvement in the dosimeter consists of adding to the ferrous-ferric system in concentrations of 10/sub -2/ to 10/sup -4/M an organic compound having one or more carboxylic or equivalent groups, such compounds being capable of chelating or complexing the iron ions in the solution. Suitable sensitizing and stabilizing agents are benzoic, phthalic, salicylic, malonic, lactic, maleic, oxalic, citric, succinic, phenolic tartaric, acetic, and adipic acid, as well as other compounds which are added to the solution alone or in certain combinations. As in conventional fluid-phase dosimeters, the absorbed dosage is correlated with a corresponding change in optical density at particular wavelengths of the solution.

  8. [The differentiation and vicissitude of variety of Aucklandiae Radix].

    PubMed

    Ma, B; Zhao, B L

    2016-01-28

    Aucklandiae Radix is a commonly used Chinese herbal medicine. Historically, the varieties of Aucklandiae Radix for its medicinal use are complicated. Early Radix Aucklandiae was produced domestically, and it began to be imported since the Northern and Southern Dynasties. The two families, four genera, including Saussure Aucklandiae Radix of Compositae, Inula Inulae Radix, Vladimiria Vladimiriae Radix, dali Aucklandiae Radix and Aristolochiaceae Aristolochic aristolochia debilis, are all applied for medicinal purposes. In modern time, there are 3 major classes of crude drugs of Aucklandiae Radix, namely, Aucklandiae Radix, Inulae Radix, root of common Vladimiriae Radix. PMID:27049740

  9. Thermoluminescence dosimeter

    SciTech Connect

    Zendle, Robert

    1985-01-01

    A thermoluminescence dosimeter having a very small rate of decline of sensitivity during subsequent uses after heating is disclosed. The dosimeter includes a detector crystal and a glass enclosure in which the detector crystal is located. The glass enclosure is air tight and is filled with a super dry inert fill gas. The inert fill gas is nonreactive with the detector crystal when the detector crystal is heated to thermoluminescence. The fill gas is selected from the group consisting of air, nitrogen, and argon, suitable admixed with 5 to 25 percent helium. The detector crystal consists essentially of calcium fluoride. The fill gas is preferably contained at a subatmospheric pressure in the glass enclosure.

  10. Thermoluminescence dosimeter

    DOEpatents

    Zendle, R.

    1983-11-03

    A thermoluminescence dosimeter having a very small rate of decline of sensitivity during subsequent uses after heating is disclosed. The dosimeter includes a detector crystal and a glass enclosure in which the detector crystal is located. The glass enclosure is air tight and is filled with a super dry inert fill gas. The inert fill gas is nonreactive with the detector crystal when the detector crystal is heated to thermoluminescence. The fill gas is selected from the group consisting of air, nitrogen, and argon, suitable admixed with 5 to 25 percent helium. The detector crystal consists essentially of calcium fluoride. The fill gas is preferably contained at a subatmospheric pressure in the glass enclosure.

  11. Composite material dosimeters

    DOEpatents

    Miller, Steven D.

    1996-01-01

    The present invention is a composite material containing a mix of dosimeter material powder and a polymer powder wherein the polymer is transparent to the photon emission of the dosimeter material powder. By mixing dosimeter material powder with polymer powder, less dosimeter material is needed compared to a monolithic dosimeter material chip. Interrogation is done with excitation by visible light.

  12. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Polymethylmethacrylate (PMMA) bone cement. 888... Polymethylmethacrylate (PMMA) bone cement. (a) Identification. Polymethylmethacrylate (PMMA) bone cement is a device... metallic prosthetic implants to living bone. (b) Classification. Class II (special controls). The...

  13. Fundamentals of gel dosimeters

    NASA Astrophysics Data System (ADS)

    McAuley, K. B.; Nasr, A. T.

    2013-06-01

    Fundamental chemical and physical phenomena that occur in Fricke gel dosimeters, polymer gel dosimeters, micelle gel dosimeters and genipin gel dosimeters are discussed. Fricke gel dosimeters are effective even though their radiation sensitivity depends on oxygen concentration. Oxygen contamination can cause severe problems in polymer gel dosimeters, even when THPC is used. Oxygen leakage must be prevented between manufacturing and irradiation of polymer gels, and internal calibration methods should be used so that contamination problems can be detected. Micelle gel dosimeters are promising due to their favourable diffusion properties. The introduction of micelles to gel dosimetry may open up new areas of dosimetry research wherein a range of water-insoluble radiochromic materials can be explored as reporter molecules.

  14. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... intended to be implanted that is made from methylmethacrylate, polymethylmethacrylate, esters of... metallic prosthetic implants to living bone. (b) Classification. Class II (special controls). The...

  15. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... intended to be implanted that is made from methylmethacrylate, polymethylmethacrylate, esters of... metallic prosthetic implants to living bone. (b) Classification. Class II (special controls). The...

  16. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... intended to be implanted that is made from methylmethacrylate, polymethylmethacrylate, esters of... metallic prosthetic implants to living bone. (b) Classification. Class II (special controls). The...

  17. Pocket radiation dosimeter--dosimeter charger assembly

    DOEpatents

    Manning, Frank W.

    1984-01-01

    This invention is a novel pocket-type radiation dosimeter comprising an electrometric radiation dosimeter and a charging circuit therefor. The instrument is especially designed to be amenable to mass production, to have a long shelf life, and to be compact, lightweight, and usable by the layman. The dosimeter proper may be of conventional design. The charging circuit includes a shake-type electrostatic generator, a voltage doubler for integrating generator output voltages of one polarity, and a switch operated by an external permanent magnet.

  18. Pocket radiation dosimeter: dosimeter charger assembly

    DOEpatents

    Manning, F.W.

    1982-03-17

    This invention is a novel pocket-type radiation dosimeter comprising an electrometric radiation dosimeter and a charging circuit therefor. The instrument is especially designed to be amenable to mass production, to have a long shelf life, and to be compact, lightweight, and usable by the layman. The dosimeter proper may be of conventional design. The charging circuit includes a shake-type electrostatic generator, a voltage doubler for integrating generator output voltages of one polarity, and a switch operated by an external permanent magnet.

  19. 21 CFR 886.1385 - Polymethylmethacrylate (PMMA) diagnostic contact lens.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... lens. 886.1385 Section 886.1385 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Polymethylmethacrylate (PMMA) diagnostic contact lens. (a) Identification. A polymethylmethacrylate (PMMA) diagnostic contact lens is a device that is a curved shell of PMMA intended to be applied for a short period of...

  20. 21 CFR 886.1385 - Polymethylmethacrylate (PMMA) diagnostic contact lens.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... lens. 886.1385 Section 886.1385 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Polymethylmethacrylate (PMMA) diagnostic contact lens. (a) Identification. A polymethylmethacrylate (PMMA) diagnostic contact lens is a device that is a curved shell of PMMA intended to be applied for a short period of...

  1. 21 CFR 886.1385 - Polymethylmethacrylate (PMMA) diagnostic contact lens.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... lens. 886.1385 Section 886.1385 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Polymethylmethacrylate (PMMA) diagnostic contact lens. (a) Identification. A polymethylmethacrylate (PMMA) diagnostic contact lens is a device that is a curved shell of PMMA intended to be applied for a short period of...

  2. 21 CFR 886.1385 - Polymethylmethacrylate (PMMA) diagnostic contact lens.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... lens. 886.1385 Section 886.1385 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Polymethylmethacrylate (PMMA) diagnostic contact lens. (a) Identification. A polymethylmethacrylate (PMMA) diagnostic contact lens is a device that is a curved shell of PMMA intended to be applied for a short period of...

  3. 21 CFR 886.1385 - Polymethylmethacrylate (PMMA) diagnostic contact lens.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... lens. 886.1385 Section 886.1385 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Polymethylmethacrylate (PMMA) diagnostic contact lens. (a) Identification. A polymethylmethacrylate (PMMA) diagnostic contact lens is a device that is a curved shell of PMMA intended to be applied for a short period of...

  4. 21 CFR 888.3027 - Polymethylmethacrylate (PMMA) bone cement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Polymethylmethacrylate (PMMA) bone cement. 888.3027 Section 888.3027 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3027 Polymethylmethacrylate (PMMA) bone cement. (a)...

  5. Smart Radiological Dosimeter

    SciTech Connect

    Kosslow, William J.; Bandzuch, Gregory S.

    2004-07-20

    A radiation dosimeter providing an indication of the dose of radiation to which the radiation sensor has been exposed. The dosimeter contains features enabling the monitoring and evaluating of radiological risks so that a user can concentrate on the task at hand. The dosimeter provides an audible alarm indication that a predetermined time period has elapsed, an audible alarm indication reminding the user to check the dosimeter indication periodically, an audible alarm indicating that a predetermined accumulated dose has been prematurely reached, and an audible alarm indication prior or to reaching the 3/4 scale point.

  6. Micromechanical radiation dosimeter

    SciTech Connect

    Thundat, T.; Sharp, S.L.; Fisher, W.G.; Warmack, R.J.; Wachter, E.A. )

    1995-03-20

    We demonstrate the use of microcantilevers coated with ultraviolet cross-linking polymers as optical radiation dosimeters. Upon exposure to radiation, a treated cantilever bends due to stress and its resonance frequency increases due to stiffening. These phenomena can be used to develop sensitive radiation dosimeters which respond to radiation affecting the mechanical properties of the selected coating.

  7. Wrist-watch dosimeter

    DOEpatents

    Wolf, M.A.; Waechter, D.A.; Umbarger, C.J.

    1982-04-16

    The disclosure is directed to a wristwatch dosimeter utilizing a CdTe detector, a microprocessor and an audio and/or visual alarm. The dosimeter is entirely housable within a conventional digital watch case having an additional aperture enabling the detector to receive radiation.

  8. Plasma modification of polymethylmethacrylate and polythyleneterephthalate surfaces

    NASA Astrophysics Data System (ADS)

    Groning, P.; Collaud, M.; Dietler, G.; Schlapbach, L.

    1994-07-01

    Noble gas (He, Ar, Xe) and reactive gas (O2, N2) plasma treatments of polymethylmethacrylate (PMMA) and polyethyleneterephthalate (PET) surfaces were performed in an electron-cyclotron-resonance plasma. In situ surface analysis by x-ray photoelectron spectroscopy reveals well-defined surface compositions. From these measurements it is concluded that, independently of the plasma gas, the plasma ions easily decompose the ester group in PMMA in its constituents by an ion-electron recombination process, while in PET the ester decomposition is less pronounced. The difference is ascribed to the presence in PET of a phenyl ring, which protects the ester group by various mechanisms. The study of O2 plasma treatments shows that the equilibrium between the depletion of oxygen and the incorporation of the reactive species in the polymer surface is solely determined by the ion current. The plasma-polymer interactions are qualtitatively explained by simple rules of intermolecular forces and ion-electron recombination phenomena.

  9. [Quality survey of different species of clematidis radix et rhizoma].

    PubMed

    Li, Qian-Qian; Ma, Chang-Hua; Liu, Chun-Sheng; Xiao, Yao; Chen, Mei-Lan; Tian, Zhi-Hao; Wang, Yuan; Kong, Fan-Yao; Xu, Wen-Ying

    2013-04-01

    Quality survey of different species of Clematidis Radix et Rhizoma was made by determining the content of hederagenin and oleanolic acid from Clematidis Radix et Rhizoma. The result showed that only a few samples of Clematis chinensis met the quality standard for Clematidis Radix et Rhizoma in Chinese Pharmacopoeia 2010 Edition. PMID:23944036

  10. Microwave dosimeter - A concept

    NASA Technical Reports Server (NTRS)

    Bartlett, R. G.; Bird, F.

    1971-01-01

    Dosimeter determines time-integrated radiation dosage to which an individual is exposed. Integration is measured chemically in proportion to radiation detected. Wearer receives an exposure measurement representing an average of the dose over the entire body.

  11. ULTRASONIC NEUTRON DOSIMETER

    DOEpatents

    Truell, R.; de Klerk, J.; Levy, P.W.

    1960-02-23

    A neutron dosimeter is described which utilizes ultrasonic waves in the megacycle region for determination of the extent of neutron damage in a borosilicate glass through ultrasonic wave velocity and attenuation measurements before and after damage.

  12. Magnetic field dosimeter development

    SciTech Connect

    Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

    1980-09-01

    In recent years there has been increased concern over potential health hazards related to exposure of personnel to magnetic fields. If exposure standards are to be established, then a means for measuring magnetic field dose must be available. To meet this need, the Department of Energy has funded development of prototype dosimeters at the Battelle Pacific Northwest Laboratory. This manual reviews the principle of operation of the dosimeter and also contains step-by-step instructions for its operation.

  13. Biocompatibility of polymethylmethacrylate resins used in dentistry.

    PubMed

    Gautam, Rupali; Singh, Raghuwar D; Sharma, Vinod P; Siddhartha, Ramashanker; Chand, Pooran; Kumar, Rakesh

    2012-07-01

    Biocompatibility or tissue compatibility describes the ability of a material to perform with an appropriate host response when applied as intended. Poly-methylmethacrylate (PMMA) based resins are most widely used resins in dentistry, especially in fabrication of dentures and orthodontic appliances. They are considered cytotoxic on account of leaching of various potential toxic substances, most common being residual monomer. Various in vitro and in vivo experiments and cell based studies conducted on acrylic based resins or their leached components have shown them to have cytotoxic effects. They can cause mucosal irritation and tissue sensitization. These studies are not only important to evaluate the long term clinical effect of these materials, but also help in further development of alternate resins. This article reviews information from scientific full articles, reviews, or abstracts published in dental literature, associated with biocompatibility of PMMA resins and it is leached out components. Published materials were searched in dental literature using general and specialist databases, like the PubMED database. PMID:22454327

  14. [Traditional Chinese medicine pairs (III)--effect of extract of Ginseng Radix et Rhizoma and Puerariae Lobatae Radix on intestinal absorption in rats].

    PubMed

    Chen, Yi-hang; Li, Meng-xuan; Meng, Zhao-qing; Yang, Jiao-jiao; Huang, Wen-zhe; Wang, Zhen-zhong; Wang, Yue-sheng; Xiao, Wei

    2015-08-01

    This study focused on the intestinal absorption of traditional Chinese medicines (TCM) to reveal the scientific connotation of the compatibility of TCM pairs. The single pass intestinal perfusion (SPIP) was used in rats to compare the absorption of single extracts from Puerariae Lobatae Radix, single extracts from Ginseng Radix et Rhizoma, combined extracts from Puerariae Lobatae Radix and Ginseng Radix et Rhizoma and Puerariae Lobatae Radix and Ginseng Radix et Rhizoma mixture in rats. The content of puerarin, ginsenoside Rg1, ginsenoside Re and ginsenoside Rb1 in liquid were tested by HPLC. The speed constant (Ka) and apparent permeability coefficients (Papp) were calculated and compared. Specifically, the order of puerarin Ka and Papp values from high to low was Ginseng Radix et Rhizoma and Puerariae Lobatae Radix mixture > single extracts from Puerariae Lobatae Radix > combined extracts from Ginseng Radix et Rhizoma and Puerariae Lobatae Radix; the order of ginsenosides Ka and Papp values from high to low was Ginseng Radix et Rhizoma and Puerariae Lobatae Radix mixture > single extracts from Ginseng Radix et Rhizoma > combined extracts from Ginseng Radix et Rhizoma and Puerariae Lobatae Radix. The combined administration of Ginseng Radix et Rhizoma and Puerariae Lobatae Radix may improve the absorption in the intestinal tract. PMID:26677717

  15. Missed canal…call from radix entomolaris

    PubMed Central

    Patil, Anil; Shigli, Anand; Tamagond, Sridevi B; Pushpalatha, C

    2014-01-01

    A comprehensive understanding of root and root canal morphology of primary teeth is valuable for successful endodontic therapy. A supernumerary root is a developmental anomaly which can affect any tooth. An extra root placed lingually (radix entomolaris) or buccally (radix paramolaris) can be seen in mandibular molars nonetheless; bilateral association of an additional root in deciduous mandibular molars is rare. This report aimed to describe the diagnosis, significance and management of an extra root in deciduous mandibular molars bilaterally in perspective of modern clinical paediatric endodontics. PMID:24626381

  16. Section 9.1 new dosimeters. New dosimetry systems

    NASA Astrophysics Data System (ADS)

    McLaughlin, William L.

    During the past two years there have been significant advances in several forms of radiation measurement systems for radiation processing, covering dose ranges of 1-10 6 Gy. Calorimeters as reference standards for both ionizing photon and electron fields have become well-established. In addition to the older ceric-cerous dosimetry solution analyzed potentiometrically, new liquid-phase dosimeters include those analyzed by spectrophotometry, e.g., improved forms of acidic aqueous solutions of K-Ag dichromate and organic radiochromic dye solutions. It has recently been demonstrated that by using certain refined sugars, e.g., D-(-) ribose, optical rotation response in aqueous solutions can be enhanced for dosimetry at doses > 10 4 Gy. There has been expanded development, use, and formulation (rods, tablets, and thin films) of the amino acid, alanine, as a solid-phase dosimeter analyzed by either ESR spectrometry or by glutamine or alanine spectrophotometry of complexes with ferric ion in the presence of a sulfonphthalein dye (xylenol orange). New commercial types of radiochromic plastic dosimeters, e.g., GafChromic TM, Riso B3 TM, GAMMACHROME YR TM, Radix TM, and Gammex TM, have been introduced and applied in practice. Improvements and broader use of optical waveguide dosimeters, e.g., Opti-Chromic TM, have also been reported, especially in food irradiation applications. Several novel dyed plastic dosimeters are available in large quantities and they lose color due to irradiation. An example is a dyed cellulosic thin film (ATC type DY-42 TM) which can be measured spectrophotometrically or densitometrically up to doses as high as 10 6 Gy.

  17. Length of stain dosimeter

    NASA Technical Reports Server (NTRS)

    Lueck, Dale E. (Inventor)

    1994-01-01

    Payload customers for the Space Shuttle have recently expressed concerns about the possibility of their payloads at an adjacent pad being contaminated by plume effluents from a shuttle at an active pad as they await launch on an inactive pad. As part of a study to satisfy such concerns a ring of inexpensive dosimeters was deployed around the active pad at the inter-pad distance. However, following a launch, dosimeters cannot be read for several hours after the exposure. As a consequence factors such as different substrates, solvent systems, and possible volatilization of HCl from the badges were studied. This observation led to the length of stain (LOS) dosimeters of this invention. Commercial passive LOS dosimeters are sensitive only to the extent of being capable of sensing 2 ppm to 20 ppm if the exposure is 8 hours. To map and quantitate the HCl generated by Shuttle launches, and in the atmosphere within a radius of 1.5 miles from the active pad, a sensitivity of 2 ppm HCl in the atmospheric gases on an exposure of 5 minutes is required. A passive length of stain dosimeter has been developed having a sensitivity rendering it capable of detecting a gas in a concentration as low as 2 ppm on an exposure of five minutes.

  18. Fundamentals of Polymer Gel Dosimeters

    NASA Astrophysics Data System (ADS)

    McAuley, Kim B.

    2006-12-01

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

  19. Simultaneous analysis of seven marker compounds from Saposhnikoviae Radix, Glehniae Radix and Peucedani Japonici Radix by HPLC/PDA.

    PubMed

    Seo, U Min; Zhao, Bing Tian; Kim, Young Ho; Kang, Jong Seong; Son, Jong Keun; Woo, Mi-Hee

    2016-05-01

    A new combination of high performance liquid chromatography (HPLC) method coupled with photodiode array (PDA) analysis has been developed for the simultaneous quantitative determination of seven major components in Saposhnikoviae Radix (SR), Glehniae Radix (GR) and Peucedani Japonici Radix (PR), namely peucedanol 7-O-β-D-glucopyranoside (1), prim-O-glucosylcimifugin (2), cimifugin (3), 4'-O-β-D-glucosyl-5-O-methylvisamminol (4), bergapten (5), sec-O-glucosylhamaudol (6), and imperatorin (7). Clear separation of these seven components were achieved on a Phenomenex Kinetex C18 (250 × 4.6 mm, 5 μm) column by gradient elution of water (A) and methanol (B) as mobile phase. The flow rate was 1.0 mL/min and the UV detector wavelength was set at 254 nm. The method was successfully used in the analysis of SR, GR, and PR with relatively simple conditions and procedures, and the results were satisfactory for linearity, recovery, precision, accuracy, stability and robustness. The results indicate that the established HPLC/PDA method is suitable for the classification of SR, GR, and PR. PMID:27016947

  20. Discrimination and Proper Use of Polygoni Multiflori Radix, Cynanchi Wilfordii Radix, and Cynanchi Auriculati Radix in Korea: A Descriptive Review

    PubMed Central

    Lee, Beom-Joon; Lee, Kyungjin

    2015-01-01

    Polygoni Multiflori Radix (PMR), Cynanchi Wilfordii Radix (CWR), and Cynanchi Auriculati Radix (CAR) are very popular herbal medicines in Traditional Korean Medicine, Traditional Chinese Medicine, and Kampo Medicine. However, the plant origins, efficacies, and traditional uses of these herbal medicines differ. In Korea, PMR is called Ha Su O (He Shou Wu in China), and CWR is called Baek Ha Su O or Baek Su O (Bai Shou Wu in China). Baek Su O refers to CWR in Korea and CAR in China. CAR has not been used as a traditional herbal medicine, and it cannot be legally used as a food or food ingredient in Korea. However, CAR is cultivated in Korea and imported from China. Because the morphology of CWR and CAR is very similar, they are often confused and misused in Korea. This review discusses the reasons for the confusion and misuse of these substances in Korea and provides the exact plant origins, efficacies, uses, components, and toxicities of PMR, CWR, and CAR so that they can be correctly understood and used. PMID:26539235

  1. Noncommercial fabrication of antibiotic-impregnated polymethylmethacrylate beads. Technical note.

    PubMed

    Flick, A B; Herbert, J C; Goodell, J; Kristiansen, T

    1987-10-01

    Antibiotic-impregnated polymethylmethacrylate (PMMA) beads were fabricated by means of injections in specially designed molds to produce small and large beads. In vitro concentrates from these beads for 30 days were found to release tobramycin in an exponential function. PMID:3652588

  2. [Effects of processing on specific toxicity and pharmacodynamics of radix Kansui, radix Achyranthis bidentatae and semen Armeniacae amarum].

    PubMed

    Nie, S; Li, Z; Liang, A; Xue, B; Li, G; Wang, X

    1996-03-01

    The comparative toxicological researches on crude and processed drugs show that the activating action of Radix Kansui, Radix Achyranthis Bidentatae and Semen Armeniacae Amarum on EBV-EA can be decreased by processing. Processing can also decrease stimulating activity on mouse skin, inhibit tumor-promoting activity in two stage skin tumor promoting test and lapactic effect by Radix Kansui. Meanwhile the pharmacological effects of these drugs can be retained or increased by processing. PMID:9206254

  3. Fractal tiles associated with shift radix systems.

    PubMed

    Berthé, Valérie; Siegel, Anne; Steiner, Wolfgang; Surer, Paul; Thuswaldner, Jörg M

    2011-01-15

    Shift radix systems form a collection of dynamical systems depending on a parameter r which varies in the d-dimensional real vector space. They generalize well-known numeration systems such as beta-expansions, expansions with respect to rational bases, and canonical number systems. Beta-numeration and canonical number systems are known to be intimately related to fractal shapes, such as the classical Rauzy fractal and the twin dragon. These fractals turned out to be important for studying properties of expansions in several settings. In the present paper we associate a collection of fractal tiles with shift radix systems. We show that for certain classes of parameters r these tiles coincide with affine copies of the well-known tiles associated with beta-expansions and canonical number systems. On the other hand, these tiles provide natural families of tiles for beta-expansions with (non-unit) Pisot numbers as well as canonical number systems with (non-monic) expanding polynomials. We also prove basic properties for tiles associated with shift radix systems. Indeed, we prove that under some algebraic conditions on the parameter r of the shift radix system, these tiles provide multiple tilings and even tilings of the d-dimensional real vector space. These tilings turn out to have a more complicated structure than the tilings arising from the known number systems mentioned above. Such a tiling may consist of tiles having infinitely many different shapes. Moreover, the tiles need not be self-affine (or graph directed self-affine). PMID:24068835

  4. Dose equivalent neutron dosimeter

    DOEpatents

    Griffith, Richard V.; Hankins, Dale E.; Tomasino, Luigi; Gomaa, Mohamed A. M.

    1983-01-01

    A neutron dosimeter is disclosed which provides a single measurements indicating the amount of potential biological damage resulting from the neutron exposure of the wearer, for a wide range of neutron energies. The dosimeter includes a detecting sheet of track etch detecting material such as a carbonate plastic, for detecting higher energy neutrons, and a radiator layer containing conversion material such as .sup.6 Li and .sup.10 B lying adjacent to the detecting sheet for converting moderate energy neutrons to alpha particles that produce tracks in the adjacent detecting sheet. The density of conversion material in the radiator layer is of an amount which is chosen so that the density of tracks produced in the detecting sheet is proportional to the biological damage done by neutrons, regardless of whether the tracks are produced as the result of moderate energy neutrons striking the radiator layer or as the result of higher energy neutrons striking the sheet of track etch material.

  5. [Thermoluminescence Slab Dosimeter].

    PubMed

    Shinsho, Kiyomitsu; Koba, Yusuke; Tamatsu, Satoshi; Sakurai, Noboru; Wakabayashi, Genichiro; Fukuda, Kazusige

    2013-01-01

    In 1953 F. Daniels et al. used the property of thermoluminescence in dosimetry for the first time. Since then, numerous TLD have been developed. 2D TLD was investigated for the first time in 1972 by P Broadhead. However, due to excessive fading, difficulties with handling and the time required for measurements, development stalled. At the current time, the majority of TLD are used in small scale, localized dosimetry with a wide dynamic range and personal dosimeters for exposure management. Urushiyama et. al. have taken advantage of the commoditization of CCD cameras in recent years--making large area, high resolution imaging easier--to introduce and develop a 2D TLD. It is expected that these developments will give rise to a new generation of applications for 2D TL dosimetry. This paper introduces the "TL Slab Dosimeter" developed jointly by Urushiyama et. al. and our team, its measurement system and several typical usage scenarios. PMID:24893451

  6. Dosimeter Badge Detects Hydrazines

    NASA Technical Reports Server (NTRS)

    Young, Rebecca C.; Travis, Joshua C.; Moore, Gerald; Rose-Pehrsson, Susan; Carver, Patricia; Brenner, Karen

    1993-01-01

    Disposable dosimeter badge indicates approximate cumulative exposure to hydrazine or monomethyl hydrazine in air. Indication is change in colors of both paper tapes; one coated with para-N, N-dimethylaminobenzaldehyde. Colors of exposed tapes compared with colors on two preprinted color wheels to obtain estimate of exposure. Badges help minimize risks associated with exposure of personnel to hydrazine or monomethyl hydrazine, or suspected carcinogens. Also used as stationary monitors by taping them on walls or equipment at strategic locations.

  7. Optical waveguide dosimeter

    SciTech Connect

    Kronenberg, S.; Levine, H.; Mclaughlin, W.L.; Siebentritt, C.R.

    1983-03-22

    An optical waveguide dosimeter for personnel dosimetry is provided including a liquid solution of leuko dye hermetically sealed in plastic tubing. Optical transport is improved by dipping the ends of the plastic tubing into clear epoxy, thus forming beads that serve as optical lenses. A layer of clear ultraviolet absorbing varnish coated on these beads and an opaque outer layer over the plastic tubing provides protection against ambient uv.

  8. [DNA barcoding identification of Ginseng Radix et Rhizoma and Panacis Quinquefolii Radix based on trnL-trnF sequences].

    PubMed

    Song, Xiao-na; Gu, Xuan; Liu, Chun-sheng; Li, Yan-peng; Zhang, Xue; Zhang, Yuan; Liu, Yong; Ma, Chang-hua

    2015-05-01

    To optimize indices of molecular identification for authentication of Ginseng Radix et Rhizoma and Panacis Quinquefolii Radix, four indices, including sequence similarity, specific positions, genetic distance and phylogenetic tree, were compared based on trnL-trnF sequences. Total DNA was extracted from Ginseng Radix et Rhizoma and Panacis Quinquefolii Radix, and trL-trnF sequences were amplified and sequenced. Sequence similarity was calculated by BLAST analysis. Specific positions were compared by DNAman software. Genetic distance and phylogenetic tree were analyzed by Mega software. The results showed that the inter-specific and intra-specific similarity of P. ginseng and P. quinquefolius respectively was 100% and 99. 6%. There were four specific positions at G153A, T463A, C732G and T818C. The inter-specific genetic distance (0) of trL-trnF sequences was lower than intra-specific genetic distance (0. 004). P. ginseng can be distinguished from P. quinquefolius based on the phylogenetic tree. It is concluded that Ginseng Radix et Rhizoma and Panacis Quinquefolii Radix can be authenticated by identification indices of sequence similarity, specific positions, genetic distance and phylogenetic tree. Index of specific positions based on trnL-trnF sequences is the most efficient index to authenticate Ginseng Radix et Rhizoma and Panacis Quinquefolii Radix. PMID:26390647

  9. Hanford personnel dosimeter supporting studies FY-1981

    SciTech Connect

    Not Available

    1982-08-01

    This report examined specific functional components of the routine external personnel dosimeter program at Hanford. Components studied included: dosimeter readout; dosimeter calibration; dosimeter field response; dose calibration algorithm; dosimeter design; and TLD chip acceptance procedures. Additional information is also presented regarding the dosimeter response to light- and medium-filtered x-rays, high energy photons and neutrons. This study was conducted to clarify certain data obtained during the FY-1980 studies.

  10. Scleroderma en coup de sabre treated with polymethylmethacrylate - Case report.

    PubMed

    Franco, Joanna Pimenta de Araujo; Serra, Márcio Soares; Lima, Ricardo Barbosa; D'Acri, Antônio Macedo; Martins, Carlos José

    2016-04-01

    The scleroderma en coup de sabre is a variant of localized scleroderma that occurs preferentially in children. The disease progresses with a proliferative and inflammatory phase and later atrophy and residual deformity, which are treated with surgical techniques such as injectable fillers, transplanted or autologous fat grafting and resection of the lesion. Among the most widely used fillers is hyaluronic acid. However, there are limitations that motivate the search for alternatives, such as polymethylmethacrylate, a permanent filler that is biocompatible, non-toxic, non-mutagenic and immunologically inert. In order to illustrate its application, a case of scleroderma en coup de sabre in a 17-year-old patient, who was treated with polymethylmethacrylate with excellent aesthetic results, is reported. PMID:27192521

  11. Delayed tentorial herniation after crainoplasty with polymethylmethacrylate: a rare complication.

    PubMed

    Yamahata, Hitoshi; Tokimura, Hiroshi; Kuratsu, Jun-ichi; Sakamoto, Akihisa; Matsuyama, Nozomu; Awa, Ryuji; Arita, Kazunori

    2011-12-01

    We report the case of a 49-year-old man who underwent a craniectomy for severe head trauma and subsequent cranioplasty with polymethylmethacrylate. He was discharged with moderate right-hand weakness. Five years after the cranioplasty he experienced double vision and slight right hemiparesis. Magnetic resonance imaging (MRI) revealed signs of tentorial herniation but no specific space-occupying lesions. The hand-moulded polymethylmethacrylate bone flap was found to be uneven and protrusions on the inner surface of the bone graft slightly compressed the brain below. His symptoms improved dramatically after a second cranioplasty using a ceramic implant. Although some complications including infection and cosmetic problems have been reported, tentorial herniation during late follow-up as a specific complication of cranioplasty has not been documented previously. We attribute his neurological improvement to the release of compression from the initial graft and to the consequent restoration of cerebrospinal fluid dynamics. PMID:21211986

  12. Scleroderma en coup de sabre treated with polymethylmethacrylate - Case report*

    PubMed Central

    Franco, Joanna Pimenta de Araujo; Serra, Márcio Soares; Lima, Ricardo Barbosa; D’Acri, Antônio Macedo; Martins, Carlos José

    2016-01-01

    The scleroderma en coup de sabre is a variant of localized scleroderma that occurs preferentially in children. The disease progresses with a proliferative and inflammatory phase and later atrophy and residual deformity, which are treated with surgical techniques such as injectable fillers, transplanted or autologous fat grafting and resection of the lesion. Among the most widely used fillers is hyaluronic acid. However, there are limitations that motivate the search for alternatives, such as polymethylmethacrylate, a permanent filler that is biocompatible, non-toxic, non-mutagenic and immunologically inert. In order to illustrate its application, a case of scleroderma en coup de sabre in a 17-year-old patient, who was treated with polymethylmethacrylate with excellent aesthetic results, is reported. PMID:27192521

  13. PERSONNEL NEUTRON DOSIMETER

    DOEpatents

    Fitzgerald, J.J.; Detwiler, C.G. Jr.

    1960-05-24

    A description is given of a personnel neutron dosimeter capable of indicating the complete spectrum of the neutron dose received as well as the dose for each neutron energy range therein. The device consists of three sets of indium foils supported in an aluminum case. The first set consists of three foils of indium, the second set consists of a similar set of indium foils sandwiched between layers of cadmium, whereas the third set is similar to the second set but is sandwiched between layers of polyethylene. By analysis of all the foils the neutron spectrum and the total dose from neutrons of all energy levels can be ascertained.

  14. Pistol-shaped dosimeter charger

    DOEpatents

    Maples, R.A.

    A pistol-shaped charger assembly clamps a cylindrical radiation dosimeter against one edge thereof. A triggerlike lever on the handgrip of the assembly is manually pivoted to actuate a piezoelectric current generator held in the handgrip and thereby charge the dosimeter.

  15. Pistol-shaped dosimeter charger

    DOEpatents

    Maples, Robert A.

    1985-01-01

    A pistol-shaped charger assembly clamps a cylindrical radiation dosimeter against one edge thereof. A triggerlike lever on the handgrip of the assembly is manually pivoted to actuate a piezoelectric current generator held in the handgrip and thereby charge the dosimeter.

  16. Piezoelectric dosimeter charger

    SciTech Connect

    Kronenberg, S.

    1981-01-27

    Disclosed is a small portable extremely rugged charger for existing pocket-sized type radiation dosimeters. The charger is comprised of a rectangularly shaped housing which contains a piezoelectric charging circuit which is manually operated by a handle to produce a relatively high charging voltage. The charging voltage is coupled to a charging post mounted on a removable cover which is adapted to be selectively rotated so that the underside of the charging post is exposed to light from one of two light windows in the housing whereupon the dosimeter scale may be viewed by either direct or reflected light from any source available. The piezoelectric charging circuit is comprised of a pair of axially aligned cylinders of piezoelectric material mounted in a fulcrum type frame having a beam lever element in contact with one of the cylinders. A spring bias element is connected to the beam lever element and is actuated by a cam attached to the handle which when rotated acts upon the spring to cause an axial compressional force to be applied to the cylinders which thereby produce the required charging voltage.

  17. Performance testing of extremity dosimeters

    SciTech Connect

    Harty, R.; Reece, W.D.; Hooker, C.D.

    1987-06-01

    The Health Physics Society Standing Committee (HPSSC) Working Group on Performance Testing of Extremity Dosimeters has issued a draft of a proposed standard for extremity dosimeters. The draft standard proposes methods to be used for testing dosimetry systems that determine occupational radiation dose to the extremities and the performance criterion used to determine compliance. The draft standard has been evaluated by testing the performance of existing processors of extremity dosimeters against the standard's proposed criterion. The proposed performance criterion is: absolute value of B + S less than or equal to 0.35, where B is the bias (calculated as the average of the performance quotients) of 15 dosimeter measurements and S is the standard deviation of the performance quotients. Dosimeter performance was tested in seven irradiation categories: low-energy photons (general and accident dosimetry), high-energy photons (general and accident dosimetry), beta particles, neutrons, and a mixture category. Twenty-one types of extremity dosimeters (both finger ring and wrist/ankle dosimeters) were received from 11 processors. The dosimeters were irradiated by the Pacific Northwest Laboratory (PNL) to specific dose levels in one or more of the seven categories as specified in the draft standard and were returned to the processors. The processors evaluated the doses and returned the results to PNL for analysis. The results were evaluated against the performance criterion specified in the draft standard. The results indicate that approximately 60% of both the finger ring and the wrist/ankle dosimeters met the performance criterion. Two-thirds of the dosimeters that did not meet the performance criterion had large biases (ranging from 0.25 to 0.80) but small standard deviations (less than 0.15). 21 refs., 3 figs., 20 tabs.

  18. Efficient radix-r adders for nanoelectronics

    NASA Astrophysics Data System (ADS)

    Moaiyeri, Mohammad Hossein; Chavoshisani, Reza; Jalali, Ali; Navi, Keivan; Hashemipour, Omid

    2016-02-01

    In this study, a new design method and efficient designs for radix-r adders are proposed for carbon nanotube field effect transistor (CNFET) FET nanotechnology. This application also investigates the capability of the nanoscale device for designing high-performance analogue circuits. The proposed designs benefit from the unique electrical properties of CNFET, such as near-ideal current voltage characteristics, very high transconductance, high-performance switches and very high-performance and high-gain binary inverters, at nanoscale. Moreover, adjustable threshold voltage and the same mobility of electrons and holes in a CNFET facilitate the design and modification procedures. The proposed design can be considered as an instance of a general adder, capable of adding radix-r digits with high precision. It is noteworthy that a very limited number of carbon nanotube diameters for designing the proposed adder are needed, which enhance the manufacturability. The proposed circuits are designed based on arithmetic relations and are also verified at 32 nm feature size using HSPICE and the Stanford standard SPICE model.

  19. Thermoluminescence dosimeter reader

    SciTech Connect

    Miyake, S.; Miura, N.

    1984-10-30

    A thermoluminescence dosimeter reader having a heater for heating a thermoluminescence element, a light measuring circuit for measuring circuit for measuring the intensity of the thermoluminescence emanated from the element when it is heated and a display device for displaying the reading of the dosage of radiation to which the element is exposed according to the intensity of the thermoluminescence is provided with a dosage information inputting means which outputs an electric signal having a value representing a predetermined reference dosage of radiation, a calculating means for calculating a calibration constant which is the ratio between the value of the electric signal and the output value of the light measuring circuit which is the measured value of the dosage of radiation of a reference thermoluminescence element which is exposed to the predetermined reference dosage of radiation, and a memory means for memorizing the calibration constant.

  20. Personnel electronic neutron dosimeter

    DOEpatents

    Falk, Roger B.; Tyree, William H.

    1984-12-18

    A personnel electronic dosimeter includes a neutron-proton and neutron-alpha converter for providing an electrical signal having a magnitude proportional to the energy of a detected proton or alpha particle produced from the converter, a pulse generator circuit for generating a pulse having a duration controlled by the weighed effect of the amplitude of the electrical signal, an oscillator enabled by the pulse for generating a train of clock pulses for a time dependent upon the pulse length, a counter for counting the clock pulses, and an indicator for providing a direct reading and aural alarm when the count indicates that the wearer has been exposed to a selected level of neutron dose equivalent.

  1. Personnel electronic neutron dosimeter

    DOEpatents

    Falk, R.B.; Tyree, W.H.

    1982-03-03

    A personnel electronic dosimeter includes a neutron-proton and neutron-alpha converter for providing an electrical signal having a magnitude proportional to the energy of a detected proton or alpha particle produced from the converter, a pulse generator circuit for generating a pulse having a duration controlled by the weighed effect of the amplitude of the electrical signal, an oscillator enabled by the pulse for generating a train of clock pulses for a time dependent upon the pulse length, a counter for counting the clock pulses, and an indicator for providing a direct reading and aural alarm when the count indicates that the wearer has been exposed to a selected level of neutron dose equivalent.

  2. Miniature spectrally selective dosimeter

    NASA Technical Reports Server (NTRS)

    Adams, R. R.; Macconochie, I. O.; Poole, B. D., Jr. (Inventor)

    1980-01-01

    A miniature spectrally selective dosimeter capable of measuring selected bandwidths of radiation exposure on small mobile areas is described. This is achieved by the combination of photovoltaic detectors, electrochemical integrators (E-cells) and filters in a small compact case which can be easily attached in close proximity to and substantially parallel to the surface being measured. In one embodiment two photovoltaic detectors, two E-cells, and three filters are packaged in a small case with attaching means consisting of a safety pin. In another embodiment, two detectors, one E-cell, three filters are packaged in a small case with attaching means consisting of a clip to clip over a side piece of an eye glass frame.

  3. Numerical investigations of shock wave propagation in polymethylmethacrylate

    NASA Astrophysics Data System (ADS)

    Popova, T. V.; Mayer, A. E.; Khishchenko, K. V.

    2015-11-01

    Using the Maxwell model of viscoelastic medium, we numerically investigate the influence of the viscoelastic properties of polymethylmethacrylate on the variation of the shock wave amplitude with depth. Parameters of the Maxwell model are chosen by comparison with experimental data on the high-speed impact of plates in order to fit the modeling results with the experimentally measured profiles of the free-surface velocity. A caloric equation of state is used to calculate the pressure from density and internal energy. It is shown that at the limit of weak shock waves, the accounting of the viscoelastic properties allows one to achieve a better agreement between calculated and experimental data for the magnitude of the shock wave velocity in comparison with the case of hydrodynamic calculations. Using the viscoelastic and hydrodynamic approaches, we investigated the dynamics of shock waves in polymethylmethacrylate initiated by micro-, nano- and picosecond pulses of pressure on the sample surface. The calculation results show that the changes in the shock wave amplitude with depth are approximately identical in the hydrodynamic and viscoelastic cases.

  4. Characterization of MOSFET dosimeters for low-dose measurements in maxillofacial anthropomorphic phantoms.

    PubMed

    Koivisto, Juha H; Wolff, Jan E; Kiljunen, Timo; Schulze, Dirk; Kortesniemi, Mika

    2015-01-01

    The aims of this study were to characterize reinforced metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters to assess the measurement uncertainty, single exposure low-dose limit with acceptable accuracy, and the number of exposures required to attain the corresponding limit of the thermoluminescent dosimeters (TLD). The second aim was to characterize MOSFET dosimeter sensitivities for two dental photon energy ranges, dose dependency, dose rate dependency, and accumulated dose dependency. A further aim was to compare the performance of MOSFETs with those of TLDs in an anthropomorphic phantom head using a dentomaxillofacial CBCT device. The uncertainty was assessed by exposing 20 MOSFETs and a Barracuda MPD reference dosimeter. The MOSFET dosimeter sensitivities were evaluated for two photon energy ranges (50-90 kVp) using a constant dose and polymethylmethacrylate backscatter material. MOSFET and TLD comparative point-dose measurements were performed on an anthropomorphic phantom that was exposed with a clinical CBCT protocol. The MOSFET single exposure low dose limit (25% uncertainty, k = 2) was 1.69 mGy. An averaging of eight MOSFET exposures was required to attain the corresponding TLD (0.3 mGy) low-dose limit. The sensitivity was 3.09 ± 0.13 mV/mGy independently of the photon energy used. The MOSFET dosimeters did not present dose or dose rate sensitivity but, however, presented a 1% decrease of sensitivity per 1000 mV for accumulated threshold voltages between 8300 mV and 17500 mV. The point doses in an anthropomorphic phantom ranged for MOSFETs between 0.24 mGy and 2.29 mGy and for TLDs between 0.25 and 2.09 mGy, respectively. The mean difference was -8%. The MOSFET dosimeters presented statistically insignificant energy dependency. By averaging multiple exposures, the MOSFET dosimeters can achieve a TLD-comparable low-dose limit and constitute a feasible method for diagnostic dosimetry using anthropomorphic phantoms. However, for single in

  5. Brachytherapy dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F. C.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2015-07-01

    In-vivo and in-situ measurement of the radiation dose administered during brachytherapy faces several technical challenges, requiring a very compact, tissue-equivalent, linear and highly sensitive dosimeter, particularly in low-dose rate brachytherapy procedures, which use radioactive seeds with low energy and low dose deposition rate. In this work we present a scintillating optical fiber dosimeter composed of a flexible sensitive probe and a dedicated electronic readout system based on silicon photomultiplier photodetection, capable of operating both in pulse and current modes. The performance of the scintillating fiber optic dosimeter was evaluated in low energy regimes, using an X-ray tube operating at voltages of 40-50 kV and currents below 1 mA, to assess minimum dose response of the scintillating fiber. The dosimeter shows a linear response with dose and is capable of detecting mGy dose variations like an ionization chamber. Besides fulfilling all the requirements for a dosimeter in brachytherapy, the high sensitivity of this device makes it a suitable candidate for application in low-dose rate brachytherapy. According to Peralta and Rego [1], the BCF-10 and BCF-60 scintillating optical fibers used in dosimetry exhibit high variations in their sensitivity for photon beams in the 25-100 kVp energy range. Energy linearity for energies below 50 keV needs to be further investigated, using monochromatic X-ray photons.

  6. [Qualitative and quantitative analysis of major constituents of Paeoniae Radix Alba and Paeoniae Radix Rubra by HPLC-DAD-Q-TOF-MS/MS].

    PubMed

    Liu, Jie; Chen, Lin; Fan, Cai-rong; Li, Huang; Huang, Ming-qing; Xiang, Qing; Xu, Wen; Xu, Wei; Chu, Ke-dan; Lin, Yu

    2015-05-01

    In order to explore the differences of chemical constituents of Paeoniae Radix Alba and Paeoniae Radix Rubra, a qualitative analytical method of liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS/MS) was developed for identification of multi-constituents and an HPLC-DAD analytical method was developed for simultaneously determining 14 major compounds (gallic acid, protocatechuic acid, paeoniflorin sulfonate, protocatechuic aldehyde, methyl gallate, oxypaeoniflorin, catechin, albiflorin, and paeoniflorin, ethyl gallate, benzoic acid, pentagaloylglucose, benzoyl-paeoniflorin, and paeonol) in Paeoniae Radix Alba and Paeoniae Radix Rubra. Q-TOF/MS qualitative analysis was performed under negative ion mode and inferred 38 components of Paeoniae Radix Alba and 30 components of Paeoniae Radix Rubra. HPLC-DAD quantitative method result showed the contents of 8 ingredients were different between Paeoniae Radix Alba and Paeoniae Radix Rubra. The results indicated that the new approach was applicable in qualitative and quantitative quality control of Paeoniae Radix Alba and Paeoniae Radix Rubra. PMID:26323145

  7. Passive dosimeters other than film and TLDs (thermoluminescent dosimeter)

    SciTech Connect

    Hankins, D.E.

    1986-05-15

    This presentation will describe CR-39 plastic as a personnel neutron dosimeter. Recent research at LLNL and elsewhere has resulted in the development of a dosimetry system that is superior to any personnel neutron dosimeter previously available. The author describes the features of the dosimetry system and the new etching procedures and techniques in detail. Most of the research was done at the LLNL and has been supported as a part of the DOE Neutron Dosimetry Upgrade Program. 10 refs., 4 figs., 1 tab.

  8. Light-activated polymethylmethacrylate nanofibers with antibacterial activity.

    PubMed

    Elashnikov, Roman; Lyutakov, Oleksiy; Ulbrich, Pavel; Svorcik, Vaclav

    2016-07-01

    The creation of an antibacterial material with triggerable properties enables us to avoid the overuse or misuse of antibacterial substances and, thus, prevent the emergence of resistant bacterial strains. As a potential light-activated antibacterial material, polymethylmethacrylate (PMMA) nanofibers doped with silver nanoparticles (AgNPs) and meso-tetraphenylporphyrin (TPP) were prepared by electrospinning. TPP was chosen as an effectively reactive oxygen species (ROS) producer. Antibacterial tests on Staphylococcus epidermidis (S. epidermidis) and Enterococcus faecalis (E. faecalis) showed the excellent light-triggerable antibacterial activity of the doped materials. Upon light irradiation at the wavelength corresponding to the TPP absorption peak (405nm), antibacterial activity dramatically increased, mostly due to the release of AgNPs from the polymer matrix. Furthermore, under prolonged light irradiation, the AgNPs/TPP/PMMA nanofibers, displayed enhanced longevity and photothermal stability. Thus, our results suggest that the proposed material is a promising option for the photodynamic inactivation of bacteria. PMID:27127048

  9. On the constancy in composition of polystyrene and polymethylmethacrylate plastics.

    PubMed

    Schulz, R J; Nath, R

    1979-01-01

    Variations in the atomic composition, and mass and electron densities of polystyrene and polymethylmethacrylate (PMM) plastics were assessed from experimentally determined mass attenuation coefficients for 125I and 137Cs gamma rays. The means and standard deviations in the mass densities of 16 samples of PMM and 10 samples of polystyrene were found to be 1.174 +/- 1.4% and 1.042 +/- 0.6% g/cm3, respectively. Based upon transmission measurements on various solutions of ethyl alcohol in water, the standard deviations in the effective atomic numbers of PMM and polystyrene were determined to be 0.77% and 1.3%, respectively. Based upon experimentally determined mass attenuation coefficients for 137Cs, the standard deviations in electron density for PMM and polystyrene were 0.5% and 1.2% respectively. Similar measurements on tap water and two grades of distilled water failed to detect any differences in atomic composition. PMID:111020

  10. Pull-out strength of screws from polymethylmethacrylate cement.

    PubMed

    Motzkin, N E; Chao, E Y; An, K N; Wikenheiser, M A; Lewallen, D G

    1994-03-01

    We aimed to determine the optimal method of inserting a screw into polymethylmethacrylate (PMMA) cement to enhance fixation. We performed six groups of ten axial pull-out tests with two sizes of screw (3.5 and 4.5 mm AO cortical) and three methods of insertion. Screws were placed into 'fluid' PMMA, into 'solid' PMMA by drilling and tapping, or into 'curing' PMMA with quarter-revolution turns every 30 seconds until the PMMA had hardened. After full hardening, we measured the maximum load to failure for each screw-PMMA construct. We found no significant difference in the pull-out strengths between screw sizes or between screws placed in fluid or solid PMMA. Screws placed in curing PMMA were significantly weaker: the relative strengths of solid, fluid and curing groups were 100%, 97% and 71%, respectively. We recommend the use of either solid or fluid insertion according to the circumstances and the preference of the surgeon. PMID:8113302

  11. Polymethylmethacrylate bone cements and additives: A review of the literature

    PubMed Central

    Arora, Manit; Chan, Edward KS; Gupta, Sunil; Diwan, Ashish D

    2013-01-01

    Polymethylmethacrylate (PMMA) bone cement technology has progressed from industrial Plexiglass administration in the 1950s to the recent advent of nanoparticle additives. Additives have been trialed to address problems with modern bone cements such as the loosening of prosthesis, high post-operative infection rates, and inflammatory reduction in interface integrity. This review aims to assess current additives used in PMMA bone cements and offer an insight regarding future directions for this biomaterial. Low index (< 15%) vitamin E and low index (< 5 g) antibiotic impregnated additives significantly address infection and inflammatory problems, with only modest reductions in mechanical strength. Chitosan (15% w/w PMMA) and silver (1% w/w PMMA) nanoparticles have strong antibacterial activity with no significant reduction in mechanical strength. Future work on PMMA bone cements should focus on trialing combinations of these additives as this may enhance favourable properties. PMID:23610754

  12. The effects of bulk versus particulate polymethylmethacrylate on bone.

    PubMed

    Goodman, S B; Fornasier, V L; Kei, J

    1988-07-01

    Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans. PMID:3289814

  13. Gold-implanted shallow conducting layers in polymethylmethacrylate

    SciTech Connect

    Teixeira, F. S.; Salvadori, M. C.; Cattani, M.; Brown, I. G.

    2009-03-15

    PMMA (polymethylmethacrylate) was ion implanted with gold at very low energy and over a range of different doses using a filtered cathodic arc metal plasma system. A nanometer scale conducting layer was formed, fully buried below the polymer surface at low implantation dose, and evolving to include a gold surface layer as the dose was increased. Depth profiles of the implanted material were calculated using the Dynamic TRIM computer simulation program. The electrical conductivity of the gold-implanted PMMA was measured in situ as a function of dose. Samples formed at a number of different doses were subsequently characterized by Rutherford backscattering spectrometry, and test patterns were formed on the polymer by electron beam lithography. Lithographic patterns were imaged by atomic force microscopy and demonstrated that the contrast properties of the lithography were well maintained in the surface-modified PMMA.

  14. Dose-equivalent neutron dosimeter

    DOEpatents

    Griffith, R.V.; Hankins, D.E.; Tomasino, L.; Gomaa, M.A.M.

    1981-01-07

    A neutron dosimeter is disclosed which provides a single measurement indicating the amount of potential biological damage resulting from the neutron exposure of the wearer, for a wide range of neutron energies. The dosimeter includes a detecting sheet of track etch detecting material such as a carbonate plastic, for detecting higher energy neutrons, and a radiator layer contaning conversion material such as /sup 6/Li and /sup 10/B lying adjacent to the detecting sheet for converting moderate energy neutrons to alpha particles that produce tracks in the adjacent detecting sheet.

  15. Effect of Radix Sophorae Flavescentis on activity of CYP450 isoforms in rats

    PubMed Central

    Chen, Lianguo; Cai, Jinzhang; Wang, Shuanghu; Hu, Lufeng; Yang, Xuezhi

    2015-01-01

    Kushen (Radix Sophorae Flavescentis) is the dried roots of Sophora Flavescens Ait, alkaloids and flavonoids are the main active constituents of Radix Sophorae Flavescentis. The influence of Radix Sophorae Flavescentis on the activities of CYP450 isoforms CYP2B6, CYP2C19, CYP1A2, CYP2C9, CYP3A4 and CYP2D6 were evaluated by cocktail method. The rats were randomly divided into Radix Sophorae Flavescentis group and control group. The Radix Sophorae Flavescentis group rats were given 5 g/kg Radix Sophorae Flavescentis decoction by intragastric administration. The six probe drugs (bupropion, omeprazole, phenacetin, tolbutamide, midazolam and metroprolol) were given to rats through intragastric administration, and the plasma concentration were determined by UPLC-MS/MS. The result of Radix Sophorae Flavescentis group compared to control group, there were statistical pharmacokinetics difference for omeprazole, phenacetin, tolbutamide and metroprolol. It indicated that the Radix Sophorae Flavescentis may induce the activities of CYP2D6, and inhibit of CYP2C19, CYP1A2 and CYP2C9 of rats. As other drugs are always used after Radix Sophorae Flavescentis, interactions between other drugs and Radix Sophorae Flavescentis undertake the risk of either diminished efficacy or adverse effects. This may give advising for reasonable drug use after Radix Sophorae Flavescentis. PMID:26885078

  16. Miniature personal UV solar dosimeter

    NASA Technical Reports Server (NTRS)

    Adams, R. R.; Macconochie, I. O.; Poole, B. D., Jr.

    1981-01-01

    Small light-powered meter measures accumulated radiation in ultraviolet or other selected regions. Practical advantages are device's low cost, small size, accuracy, and adaptability to specific wave-band measurements. Medical applications include detection of skin cancer, vitamin D production, and jaundice. Dosimeter also measures sunlight for solar energy designs, agriculture and meteorology, and monitors stability of materials and environmental and occupational lighting.

  17. Surface topographical and structural analysis of Ag+-implanted polymethylmethacrylate

    NASA Astrophysics Data System (ADS)

    Arif, Shafaq; Rafique, M. Shahid; Saleemi, Farhat; Naab, Fabian; Toader, Ovidiu; Sagheer, Riffat; Bashir, Shazia; Zia, Rehana; Siraj, Khurram; Iqbal, Saman

    2016-08-01

    Specimens of polymethylmethacrylate (PMMA) were implanted with 400-keV Ag+ ions at different ion fluences ranging from 1 × 1014 to 5 × 1015 ions/cm2 using a 400-kV NEC ion implanter. The surface topographical features of the implanted PMMA were investigated by a confocal microscope. Modifications in the structural properties of the implanted specimens were analyzed in comparison with pristine PMMA by X-ray diffraction (XRD) and Raman spectroscopy. UV-Visible spectroscopy was applied to determine the effects of ion implantation on optical transmittance of the implanted PMMA. The confocal microscopic images revealed the formation of hillock-like microstructures along the ion track on the implanted PMMA surface. The increase in ion fluence led to more nucleation of hillocks. The XRD pattern confirmed the amorphous nature of pristine and implanted PMMA, while the Raman studies justified the transformation of Ag+-implanted PMMA into amorphous carbon at the ion fluence of ⩾5 × 1014 ions/cm2. Moreover, the decrease in optical transmittance of PMMA is associated with the formation of hillocks and ion-induced structural modifications after implantation.

  18. Integrity of Polymethylmethacrylate (PMMA) Chemically Welded Joints Examined

    NASA Technical Reports Server (NTRS)

    Lerch, Bradley A.; Thesken, John C.; Bunnell, Charles T.; Kurta, Carol E.; Sydenstricker, Mike

    2005-01-01

    NASA Glenn Research Center s Capillary Flow Experiments (CFE) program is developing experiment payloads to explore fluid interfaces in microgravity on the International Space Station. The information to be gained from the CFE is relevant to the design of fluid-bearing systems in which capillary forces predominate, for example in the passive positioning of liquids in spacecraft fuel tanks. To achieve the science goals of CFE, Glenn researchers constructed several types of experiment vessels. One type of vessel, known as the interior corner flow (ICF), will be used to determine important transients for low-gravity liquid management in a two-phase system. Each vessel has a cylindrical fluid reservoir connected to each end of the test chamber by internal transport tubes, each with a quarter-turn shutoff valve (see the following photograph). These multipiece vessels are made from polymethylmethacrylate (PMMA) because of its excellent optical properties (i.e., the fluids can be observed easily in the vessel). Because of the complexity of certain vessels, the test chamber had to be manufactured in pieces and welded chemically. Some past experience with adhesive bonded plastic showed that the experiment fluid degraded the adhesive to the point of failure. Therefore, it was necessary to see if the fluid also degraded the chemically welded PMMA joints.

  19. Polymethylmethacrylate-induced release of bone-resorbing factors

    SciTech Connect

    Herman, J.H.; Sowder, W.G.; Anderson, D.; Appel, A.M.; Hopson, C.N. )

    1989-12-01

    A pseudomembranous structure that has the histological characteristics of a foreign-body-like reaction invariably develops at the bone-cement interface in the proximity of resorption of bone around aseptically loosened cemented prostheses. This study was an attempt to implicate polymethylmethacrylate in this resorptive process. Unfractionated peripheral-blood mononuclear cells (consisting of lymphocytes and monocytes) and surface-adherent cells (monocyte-enriched) were prepared from control subjects who did and did not have clinical evidence of osteoarthrosis and from patients who had osteoarthrosis and were having a revision for failure of a cemented hip or knee implant. Cells were cultured for varying periods in the presence and absence of nonpolymerized methacrylate (one to two-micrometer spherules), pulverized polymerized material, or culture chambers that were pre-coated with polymerized cement. Conditioned media that were derived from both methacrylate-stimulated cell populations were shown to contain specific bone-resorbing mediators (interleukin-1, tumor necrosis factor, or prostaglandin E2) and to directly affect bone resorption in 45Ca-labeled murine limb-bone assays.

  20. RADIATION DOSIMETER AND DOSIMETRIC METHODS

    DOEpatents

    Taplin, G.V.

    1958-10-28

    The determination of ionizing radiation by means of single fluid phase chemical dosimeters of the colorimetric type is presented. A single fluid composition is used consisting of a chlorinated hydrocarbon, an acidimetric dye, a normalizer and water. Suitable chlorinated hydrocarbons are carbon tetrachloride, chloroform, trichloroethylene, trichlorethane, ethylene dichioride and tetracbloroethylene. Suitable acidimetric indicator dyes are phenol red, bromcresol purple, and creosol red. Suitable normallzers are resorcinol, geraniol, meta cresol, alpha -tocopberol, and alpha -naphthol.

  1. Characterization of porous polymethylmethacrylate space maintainers for craniofacial reconstruction.

    PubMed

    Wang, Limin; Yoon, Diana M; Spicer, Patrick P; Henslee, Allan M; Scott, David W; Wong, Mark E; Kasper, F Kurtis; Mikos, Antonios G

    2013-07-01

    Porous polymethylmethacrylate (PMMA) has been used as an alloplastic bone substitute in the craniofacial complex, showing integration with the surrounding soft and hard tissue. This study investigated the physicochemical properties of curing and cured mixtures of a PMMA-based bone cement and a carboxymethylcellulose (CMC) gel porogen. Four formulations yielding porous PMMA of varied porosity were examined; specifically, two groups containing 30% (w/w) CMC gel in the mixture using a 7% (w/v) or 9% (w/v) stock CMC gel (30-7 and 30-9, respectively) and two groups containing 40% (w/w) CMC gel (40-7 and 40-9). An additional group comprising solid PMMA without CMC was investigated. The incorporation of the CMC gel into the PMMA bone cement during polymerization decreased the setting time from 608 ± 12 s for the solid PMMA to 427 ± 10 s for the 40-9 group, and decreased the maximum temperature from 81 ± 4°C for the solid PMMA to 38 ± 2°C for the 40-9 group. The porous PMMA groups exhibited reduced compressive strength and bending modulus and strength relative to the solid PMMA. All the porous PMMA formulations released more unconverted methylmethacrylate (MMA) monomer and N,N-dimethyl-p-toluidine (DMT) from cured specimens and less MMA and DMT from curing specimens than the solid PMMA. The data suggest that the physicochemical properties of the porous PMMA formulations are appropriate for their application in craniofacial space maintenance. PMID:23359449

  2. Kinetic peculiarities of rhodamine 6G photodegradation in polymethylmethacrylate

    SciTech Connect

    Mardaleishvili, I.R.; Anisimov, V.M.

    1986-10-01

    Dye-activated polymer matrices have found recently wide technological applications as active laser media. The kinetic mechanism for dye photodegradation has been studied in this work for polymethylmethacrylate (PMMA) activated by rhodamine 6G (R6G). It has been found that the dye molecules are not equivalent with respect to their stability to the light and the effective width of their distribution over this parameter depends on the photon energy acting on the system. For the short wavelength UV irradiation (lambda = 254 nm) the distribution is narrow and it widens with an increase in the excitation wavelength. Optically transparent PMMA films (molecular weight 160,000 and thickness ca.20 mum) have been used in the present work. The necessity of accounting for the kinetics and effectiveness of the relaxation processes leading to a change in the reactivity of the molecules added to the polymer matrix limit the applicability of the kinetic stabilization method. A detailed study of the relaxation processes has been carried out, where it has been demonstrated for a number of polymer matrices, including PMMA, that a relaxation of guest molecules, leading to an enhancement of their reactivity, is effective only at the temperatures close to T /SUB c/ of the polymer. For PMMA activated by R6G the dark incubation of the previously irradiated sample for 30 min at 90 C leads to a substantial increase in the further photodegradation process. This is due to the fact that the relaxation process leads to an increased fraction of the highly reactive molecules. Diagrams are included.

  3. Daptomycin-loaded polymethylmethacrylate bone cement for joint arthroplasty surgery.

    PubMed

    Hsu, Yuan-Ming; Liao, Chun-Hsing; Wei, Yu-Hong; Fang, Hsu-Wei; Hou, Hsiang-Huan; Chen, Chia-Chun; Chang, Chih-Hung

    2014-06-01

    Antibiotic-loaded acrylic bone cement has been frequently used as an infection prophylaxis or antibiotic-loaded spacer in infected arthroplasty. In addition, daptomycin has been used recently against broad spectrum Gram-positive organisms. The goal of this in vitro study is to investigate the bacteriacidal and mechanical properties of daptomycin-incorporated polymethylmethacrylate (PMMA) bone cement and evaluate its feasibility for clinical use. Daptomycin (0.5, 1, or 2 g) was premixed with 40 g of PMMA bone cement powder before curing. The mechanical properties of the daptomycin-loaded acrylic bone cement (DLABC) were estimated following standard guidance, and the release profile and kinetics of daptomycin from PMMA were analyzed. The antimicrobial efficacy of DLABC was determined with a zone of inhibition (ZOI) assay against Staphylococcus aureus, Staphylococcus epidermis, Enterococcus faecalis, and Enterococcus faecium, respectively. The results showed that the compressive strength, of PMMA bone cement, which was higher than 100 MPa in all groups, was sufficient according to ISO 5833 after incorporation of daptomycin. The encapsulated daptomycin was released for 2 weeks with a 9.59 ± 0.85%, 15.25 ± 0.69%, and 20.64 ± 20.33% released percentage on the first day in the low, mid, and high groups, respectively. According to the calculated release kinetics, incorporated daptomycin should be 3.3 times the original dose to double its release. Although all recipes of DLABC had a microbial inhibitory effect, the effect with a higher encapsulated amount of daptomycin was more significant. Therefore, we believe that daptomycin can be locally delivered from PMMA bone cement at the surgical site as a prophylactic or treatment for osteomyelitis against Gram-positive organisms with intact cement function. PMID:24571555

  4. Fast-neutron solid-state dosimeter

    DOEpatents

    Kecker, K.H.; Haywood, F.F.; Perdue, P.T.; Thorngate, J.H.

    1975-07-22

    This patent relates to an improved fast-neutron solid-state dosimeter that does not require separation of materials before it can be read out, that utilizes materials that do not melt or otherwise degrade at about 300$sup 0$C readout temperature, that provides a more efficient dosimeter, and that can be reused. The dosimeters are fabricated by intimately mixing a TL material, such as CaSO$sub 4$:Dy, with a powdered polyphenyl, such as p-sexiphenyl, and hot- pressing the mixture to form pellets, followed by out-gassing in a vacuum furnace at 150$sup 0$C prior to first use dosimeters. (auth)

  5. TL and OSL dose response of LiF:Mg,Ti and Al2O3:C dosimeters using a PMMA phantom for IMRT technique quality assurance.

    PubMed

    Matsushima, Luciana C; Veneziani, Glauco R; Sakuraba, Roberto K; Cruz, José C; Campos, Letícia L

    2015-06-01

    The principle of IMRT is to treat a patient from a number of different directions (or continuous arcs) with beams of nonuniform fluences, which have been optimized to deliver a high dose to the target volume and an acceptably low dose to the surrounding normal structures (Khan, 2010). This study intends to provide information to the physicist regarding the application of different dosimeters type, phantoms and analysis technique for Intensity Modulated Radiation Therapy (IMRT) dose distributions evaluation. The measures were performed using dosimeters of LiF:Mg,Ti and Al2O3:C evaluated by techniques of thermoluminescent (TL) and Optically Stimulated Luminescence (OSL). A polymethylmethacrylate (PMMA) phantom with five cavities, two principal target volumes considered like tumours to be treated and other three cavities to measure the scattered radiation dose was developed to carried out the measures. PMID:25698672

  6. A Case Report of Allergic Contact Dermatitis due to Mandragora Radix

    PubMed Central

    Baysak, Sevim; Gönül, Müzeyyen; Atacan, Damla; Ergin, Can

    2015-01-01

    An 82-year-old male presented with rash, burning, and itching on his knees that had started 4 days after the local application of Mandragora Radix sap for 3 consecutive days. A dermatological examination revealed erythematous, edematous, and scaly plaque lesions on the patient's knees. An open application test with M. Radix was performed, and the patient was diagnosed with allergic contact dermatitis due to M. Radix. Mandragora species, which belong to the Solanaceae family, have sedative, aphrodisiac, emetic, analgesic, and anesthetic properties. To the best of our knowledge, only one case of M. Radix-induced allergic contact dermatitis has been previously reported. PMID:26347280

  7. [Advance in research on chemical constituents from Notopterygii Rhizoma et Radix].

    PubMed

    Li, Shi-ping; Sha, Long; Zhao, Yi-wu; Xu, Zhi-liang; Huang, Wen-zhe; Wang, Zhen-zhong; Xiao, Wei

    2015-08-01

    This paper summarized the recent 30 years research progress of the chemical constituents from Notopterygii Rhizoma et Radix. The chemical constituents from Notopterygii Rhizoma et Radix mainly consist of coumarins, polyene-polyacetylenes, sesquiterpenes, phenolic acids, while steroids and flavonoids were less reported. All constituents were confirmed and corrected through SciFinder. We also checked the Chinese name and English name and listed the CAS number of each compound. It can provide some guidelines for the research, development and utilization of Notopterygii Rhizoma et Radix in the future. Whether there is columbianin in the Notopterygii Rhizoma et Radix need to be further researched. PMID:26677692

  8. BETA-GAMMA PERSONNEL DOSIMETER

    DOEpatents

    Davis, D.M.; Gupton, E.D.; Hart, J.C.; Hull, A.P.

    1961-01-17

    A personnel dosimeter is offered which is sensitive to both gamma and soft beta radiations from all directions within a hemisphere. The device is in the shape of a small pill box which is worn on a worker-s wrist. The top and sides of the device are provided with 50 per cent void areas to give 50 per cent response to the beta rays and complete response to the gamma rays. The device is so constructed as to have a response which will approximate the dose received by the basal layer of the human epidermis.

  9. Portable neutron spectrometer and dosimeter

    DOEpatents

    Waechter, D.A.; Erkkila, B.H.; Vasilik, D.G.

    The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

  10. Portable neutron spectrometer and dosimeter

    DOEpatents

    Waechter, David A.; Erkkila, Bruce H.; Vasilik, Dennis G.

    1985-01-01

    The disclosure relates to a battery operated neutron spectrometer/dosimeter utilizing a microprocessor, a built-in tissue equivalent LET neutron detector, and a 128-channel pulse height analyzer with integral liquid crystal display. The apparatus calculates doses and dose rates from neutrons incident on the detector and displays a spectrum of rad or rem as a function of keV per micron of equivalent tissue and also calculates and displays accumulated dose in millirads and millirem as well as neutron dose rates in millirads per hour and millirem per hour.

  11. Quantum Mechanics and the Principle of Least Radix Economy

    NASA Astrophysics Data System (ADS)

    Garcia-Morales, Vladimir

    2015-03-01

    A new variational method, the principle of least radix economy, is formulated. The mathematical and physical relevance of the radix economy, also called digit capacity, is established, showing how physical laws can be derived from this concept in a unified way. The principle reinterprets and generalizes the principle of least action yielding two classes of physical solutions: least action paths and quantum wavefunctions. A new physical foundation of the Hilbert space of quantum mechanics is then accomplished and it is used to derive the Schrödinger and Dirac equations and the breaking of the commutativity of spacetime geometry. The formulation provides an explanation of how determinism and random statistical behavior coexist in spacetime and a framework is developed that allows dynamical processes to be formulated in terms of chains of digits. These methods lead to a new (pre-geometrical) foundation for Lorentz transformations and special relativity. The Parker-Rhodes combinatorial hierarchy is encompassed within our approach and this leads to an estimate of the interaction strength of the electromagnetic and gravitational forces that agrees with the experimental values to an error of less than one thousandth. Finally, it is shown how the principle of least-radix economy naturally gives rise to Boltzmann's principle of classical statistical thermodynamics. A new expression for a general (path-dependent) nonequilibrium entropy is proposed satisfying the Second Law of Thermodynamics.

  12. Design of an advanced TLD-based fixed nuclear accident dosimeter

    SciTech Connect

    Casson, W.H.; Mei, G.T.

    1993-08-01

    A new system has been designed for use as a fixed nuclear accident dosimeter based upon the thermoluminescent dosimeter (TLD) system used for personnel dosimetry at US Department of Energy facilities managed by Martin Marietta Energy Systems, Inc. The system is made up of a small phantom consisting of two main parts measuring 20 x 20 x 5 cm and made from polymethylmethacrylate. A neutron-sensitive TLD card is placed in the center between the two pieces. Also, TLD cards in standard holders are mounted on the front and back of the phantom. A derivation is made of a linear combination of the responses from the TLD elements which results in calculation of the neutron fluence, absorbed dose, and dose equivalent. By using the right linear combinations, a crude spectrum can be estimated, which allows further calculation of the average fluence-to-dose-equivalent conversion factor. The response of the system was tested and found to be applicable for the evaluation of typical nuclear accident spectra, although considerable improvement can be made by the addition of a sulfur pellet. The system was also tested for angular dependence. In order to move the development of this system from the proof-of-principle to full application, the calculation of the TLD resonse curves must be improved, additional measurements must be made, and the system must be tested in a simulated accident neutron field. The advantages of the new fixed dosimeter system are its simplicity, easy maintenance, and lower operational cost. The system uses standard TLD cards that are already in place throughout Energy Systems facilities. The TLD process personnel are famliiar with evaluating doses from TLDs and can provide information necessary to ensure timely and accurate assessment of exposures that may result from riticality accidents. Most of the quality control requirements are part of the existing personnel dosimetry system.

  13. Molecular authentication of Radix Puerariae Lobatae and Radix Puerariae Thomsonii by ITS and 5S rRNA spacer sequencing.

    PubMed

    Sun, Ye; Shaw, Pang-Chui; Fung, Kwok-Pui

    2007-01-01

    In the present study, we examined nuclear DNA sequences in an attempt to reveal the relationships between Pueraria lobata (Willd). Ohwi, P. thomsonii Benth., and P. montana (Lour.) Merr. We found that internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA are highly divergent in P. lobata and P. thomsonii, and four types of ITS with different length are found in the two species. On the other hand, DNA sequences of 5S rRNA gene spacer are highly conserved across multiple copies in P. lobata and P. thomsonii, they could be used to identify P. lobata, P. thomsonii, and P. montana of this complex, and may serve as a useful tool in medical authentication of Radix Puerariae Lobatae and Radix Puerariae Thomsonii. PMID:17202681

  14. [Comparative study on preparation of Polygoni Multiflori Radix based on hepatotoxic bioassay].

    PubMed

    Ma, Zhi-jie; Li, Xiao-fei; Lv, Yang; Jiang, Bing-qian; Zhao, Yan-ling; Zhang, Ya-ming; Zhao, Kui-jun; Wang, Jia-bo; Xiao, Xiao-he

    2015-06-01

    Toxicity of different processed was evaluated Polygoni Multiflori Radix by determining the hepatotoxic potency for selecting processing technology. Process Polygoni Multiflori Radix using high pressure steamed, Black Bean high pressure steamed, atmospheric steamed for different time. Using normal human hepatocytes (L02) as evaluation model, hepatotoxic potency as index to evaluate hepatotoxic potency of different processed Polygoni Multiflori Radix. Analysis chemical composition of some processed products by UPLC-MS. Hepatotoxic bioassay method cloud evaluate the toxicity of different Polygoni Multiflori Radix samples. Different processing methods can reduce the toxicity of Polygoni Multiflori Radix, high pressure steamed three hours attenuated was better. Different processing methods have different effects on chemical constituents of Polygoni Multiflori Radix. Comparing with crude sample, the contents of gallic acid, 2,3,5,4-tetrahydroxyl diphenylethylene-2-O-glucoside, emodin-8-O-beta glucoside and emodin were decreased in processed products with 3 kinds of different methods. The change trend of 2,3,5,4-tetrahydroxyl diphenylethylene-2-O-glucoside content was similar with hepatotoxic potency. Different processing methods can reduce the toxicity of Polygoni Multiflori Radix. Processing methods and time attenuated obvious impact on toxicity. Recommended further research on the attehuated standard control of Polygoni Multiflori Radix concocted. PMID:26591518

  15. Two Traditional Chinese Medicines Curcumae Radix and Curcumae Rhizoma: An Ethnopharmacology, Phytochemistry, and Pharmacology Review.

    PubMed

    Zhou, Yang; Xie, Meng; Song, Yan; Wang, Wenping; Zhao, Haoran; Tian, Yuxin; Wang, Yan; Bai, Shaojuan; Zhao, Yichen; Chen, Xiaoyi; She, Gaimei

    2016-01-01

    Curcumae Rhizoma, known as Ezhu (Chinese: ), and Curcumae Radix, known as Yujin (Chinese: ), are different plant parts coming from three same species according to China Pharmacopoeia. Actually, they are used in different ways in TCM clinical treatment. Curcumae Rhizoma is mainly used as antitumor drug, while Curcumae Radix has been used as antidepressant and cholagogue. Curcumae Rhizoma and Curcumae Radix are confused in variety and source, even in clinical trials by some nonprofessional workers. So it is important for us to make them clear. This review is aimed at summarizing the ethnopharmacology, phytochemical, and pharmacological differences between Curcumae Radix and Curcumae Rhizoma by SciFinder, CNKI, and so on, to use them exactly and clearly. Further studies on Curcumae Rhizoma and Curcumae Radix can lead to the development of new drugs and therapeutics for various diseases on the basis of the TCM theory. PMID:27057197

  16. Two Traditional Chinese Medicines Curcumae Radix and Curcumae Rhizoma: An Ethnopharmacology, Phytochemistry, and Pharmacology Review

    PubMed Central

    Zhou, Yang; Xie, Meng; Song, Yan; Wang, Wenping; Zhao, Haoran; Tian, Yuxin; Wang, Yan; Bai, Shaojuan; Zhao, Yichen; Chen, Xiaoyi; She, Gaimei

    2016-01-01

    Curcumae Rhizoma, known as Ezhu (Chinese: 莪术), and Curcumae Radix, known as Yujin (Chinese: 郁金), are different plant parts coming from three same species according to China Pharmacopoeia. Actually, they are used in different ways in TCM clinical treatment. Curcumae Rhizoma is mainly used as antitumor drug, while Curcumae Radix has been used as antidepressant and cholagogue. Curcumae Rhizoma and Curcumae Radix are confused in variety and source, even in clinical trials by some nonprofessional workers. So it is important for us to make them clear. This review is aimed at summarizing the ethnopharmacology, phytochemical, and pharmacological differences between Curcumae Radix and Curcumae Rhizoma by SciFinder, CNKI, and so on, to use them exactly and clearly. Further studies on Curcumae Rhizoma and Curcumae Radix can lead to the development of new drugs and therapeutics for various diseases on the basis of the TCM theory. PMID:27057197

  17. [Determination of trace elements in radix ophiopogonis by HG-ICP-AES].

    PubMed

    Lou, Qi-Zheng; Xu, Run-Sheng

    2007-06-01

    In this paper, a method of microwave digestion technique for the contents determination of trace elements Ni, Zn, Mn, Cu, Mg, Fe, Ca and Pb in radix ophiopogonis by hydride generation inductively coupled plasma atomic emition spectrometry (HG-ICP-AES) was reported. Its recovery ratio obtained by standard addition method ranged between 97.8% and 102.5%, and its RSD was lower than 4.0%. The results of the determination show that radix ophiopogonis is rich in the inorganic elements such as Fe, and the content of Zn in radix ophiopogonis of Zhejiang is much higher in radix ophiopogonis of Sichun. The result will provide scientific data for the study on the elements in radix ophiopogonis and on their relativity of medicine efficacy. PMID:17763797

  18. Dosimeter and method for using the same

    DOEpatents

    Warner, Benjamin P.; Johns, Deidre M.

    2003-06-24

    A very sensitive dosimeter that detects ionizing radiation is described. The dosimeter includes a breakable sealed container. A solution of a reducing agent is inside the container. The dosimeter has an air-tight dosimeter body with a transparent portion and an opaque portion. The transparent portion includes a transparent chamber that holds the breakable container with the reducing agent. The opaque portion includes an opaque chamber that holds an emulsion of silver salt (AgX) selected from silver chloride, silver bromide, silver iodide, and combinations of them. A passageway in the dosimeter provides fluid communication between the transparent chamber and the opaque chamber. The dosimeter may also include a chemical pH indicator in the breakable container that provides a detectable color change to the solution for a pH of about 3-10. The invention also includes a method of detecting ionizing radiation that involves producing the dosimeter, breaking the breakable container, allowing the solution to flow through the passageway and contact the emulsion, detecting any color change in the solution and using the color change to determine a radiation dosage.

  19. 21 CFR 177.2465 - Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers. 177.2465 Section 177.2465 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only...

  20. 21 CFR 177.2465 - Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers. 177.2465 Section 177.2465 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only...

  1. 21 CFR 177.2465 - Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Polymethylmethacrylate/poly(trimethoxysilylpropyl)methacrylate copolymers. 177.2465 Section 177.2465 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use Only as Components of Articles Intended...

  2. Radiation monitoring equipment dosimeter experiment

    NASA Astrophysics Data System (ADS)

    Hardy, Kenneth A.; Golightly, Michael J.; Quam, William

    Spacecraft crews risk exposure to relatively high levels of ionizing radiation. This radiation may come from charged particles trapped in the Earth's magnetic fields, charged particles released by solar flare activity, galactic cosmic radiation, energetic photons and neutrons generated by interaction of these primary radiations with spacecraft and crew, and man-made sources (e.g., nuclear power generators). As missions are directed to higher radiation level orbits, viz., higher altitudes and inclinations, longer durations, and increased flight frequency, radiation exposure could well become a major factor for crew stay time and career lengths. To more accurately define the radiological exposure and risk to the crew, real-time radiation monitoring instrumentation, which is capable of identifying and measuring the various radiation components, must be flown. This presentation describes a radiation dosimeter instrument which was successfully flown on the Space Shuttle, the RME-3.

  3. Radiation Monitoring Equipment Dosimeter Experiment

    NASA Technical Reports Server (NTRS)

    Hardy, Kenneth A.; Golightly, Michael J.; Quam, William

    1992-01-01

    Spacecraft crews risk exposure to relatively high levels of ionizing radiation. This radiation may come from charged particles trapped in the Earth's magnetic fields, charged particles released by solar flare activity, galactic cosmic radiation, energetic photons and neutrons generated by interaction of these primary radiations with spacecraft and crew, and man-made sources (e.g., nuclear power generators). As missions are directed to higher radiation level orbits, viz., higher altitudes and inclinations, longer durations, and increased flight frequency, radiation exposure could well become a major factor for crew stay time and career lengths. To more accurately define the radiological exposure and risk to the crew, real-time radiation monitoring instrumentation, which is capable of identifying and measuring the various radiation components, must be flown. This presentation describes a radiation dosimeter instrument which was successfully flown on the Space Shuttle, the RME-3.

  4. [Optmization for cutting procedure of astragali radix with Box-Behnken design and response surface method].

    PubMed

    Shen, Xiu-Juan; Zhou, Qian; Sun, Li-Li; Dai, Yan-Peng; Yan, Xue-Sheng

    2014-07-01

    Astragali Radix was firstly recorded in the "Shen Nong's Herbal Classic" as a top-grade and commonly used traditional Chinese medicine. Its frequently used slices include raw Astragali Radix and honey-processed products. In current studies, many reports were made on honey-processed Astragali Radix, whereas fewer study reports were made on the cutting process of Astragali Radix. Currently, because Astragali Radix is primarily cut by drug workers according to their operating experience, but with out specific cutting parameters, it is easy to cause the loss or mildew of active ingredients. As a result, the quality of Astragali Radix circulated in the market is not guaranteed, and the quality of their slices and preparations are hard to be controlled, which seriously impact the clinical efficacy. In response, this experiment was performed, in which the optimum cutting process of Astragali Radix was taken as the study objective, the Box-Benhnken central composite design in the response surface analysis was adopted, and the content and appearance character of astragaloside and calycosin-7-glucoside were regarded as the study indicators. Three factors, namely the softening time, the drying temperature and the drying time, were selected to optimize the cutting process of Astragali Radix and obtain the optimum cutting process parameters as follows: the softening time was 3 hours, the drying temperature was 50 degrees C, and the drying time was 4 hours. According to the verification test, the Astragali Radix cutting process is steady and feasible, which has certain significance for normalizing the cutting process of Astragali Radix. PMID:25276971

  5. Comparative study of some new EPR dosimeters

    NASA Astrophysics Data System (ADS)

    Alzimami, K. S.; Maghraby, Ahmed M.; Bradley, D. A.

    2014-02-01

    Investigations have been made of four new radiation dosimetry EPR candidates from the same family of materials: sulfamic acid, sulfanillic acid, homotaurine, and taurine. Mass energy attenuation coefficients, mass stopping power values and the time dependence of the radiation induced radicals are compared. Also investigated are the microwave saturation behavior and the effect of applied modulation amplitude on both peak-to-peak line width (WPP) and peak-to-peak signal height (HPP). The dosimeters are characterized by simple spectra and stable radiation-induced radicals over reasonable durations, especially in taurine dosimeters. Sulfamic acid dosimeters possessed the highest sensitivity followed by taurine and homotaurine and sulfanillic.

  6. Fiber-type dosimeter with improved illuminator

    DOEpatents

    Fox, R.J.

    1985-12-23

    A single-piece, molded plastic, Cassigrainian-type condenser arrangement is incorporated in a tubular-shaped personal pocket dosimeter of the type which combines an ionization chamber with an optically-read fiber electrometer to provide improved illumination of the electrometer fiber. The condenser routes incoming light from one end of the dosimeter tubular housing around a central axis charging pin assembly and focuses the light at low angles to the axis so that it falls within the acceptance angle of the electrometer fiber objective lens viewed through an eyepiece lens disposed in the opposite end of the dosimeter. This results in improved fiber illumination and fiber image contrast.

  7. Fiber-type dosimeter with improved illuminator

    DOEpatents

    Fox, Richard J.

    1987-01-01

    A single-piece, molded plastic, Cassigrainian-type condenser arrangement is incorporated in a tubular-shaped personal pocket dosimeter of the type which combines an ionization chamber with an optically-read fiber electrometer to provide improved illumination of the electrometer fiber. The condenser routes incoming light from one end of the dosimeter tubular housing around a central axis charging pin assembly and focuses the light at low angles to the axis so that it falls within the acceptance angle of the electrometer fiber objective lens viewed through an eyepiece lens disposed in the opposite end of the dosimeter. This results in improved fiber illumination and fiber image contrast.

  8. Use of wrist albedo neutron dosimeters

    SciTech Connect

    Hankins, D.E.

    1983-01-01

    We are developing a wrist dosimeter that can be used to measure the exposure at the wrist to x-rays, gamma rays, beta-particles, thermal neutrons and fast neutrons. It consists of a modified Hankins Type albedo neutron dosimeter and also contains three pieces of CR-39 plastic. ABS plastic in the form of an elongated hemisphere provides the beta and low energy x-ray shielding necessary to meet the requirement of depth dose measurements at 1 cm. The dosimeter has a beta window located in the side of the hemisphere oriented towards an object being held in the hands. A TLD 600 is positioned under the 1 cm thick ABS plastic and is used to measure the thermal neutron dose. At present we are using Velcro straps to hold the dosimeter on the inside of the wrist. 9 figures.

  9. Polymer gel dosimeter based on itaconic acid.

    PubMed

    Mattea, Facundo; Chacón, David; Vedelago, José; Valente, Mauro; Strumia, Miriam C

    2015-11-01

    A new polymeric dosimeter based on itaconic acid and N, N'-methylenebisacrylamide was studied. The preparation method, compositions of monomer and crosslinking agent and the presence of oxygen in the dosimetric system were analyzed. The resulting materials were irradiated with an X-ray tube at 158cGy/min, 226cGymin and 298cGy/min with doses up to 1000Gy. The dosimeters presented a linear response in the dose range 75-1000Gy, sensitivities of 0.037 1/Gyat 298cGy/min and an increase in the sensitivity with lower dose rates. One of the most relevant outcomes in this study was obtaining different monomer to crosslinker inclusion in the formed gel for the dosimeters where oxygen was purged during the preparation method. This effect has not been reported in other typical dosimeters and could be attributed to the large differences in the reactivity among these species. PMID:26275817

  10. Performance criteria for dosimeter angular response

    SciTech Connect

    Roberson, P.L.; Fox, R. A.; Cummings, F. M.; McDonald, J. C.; Jones, K.L.

    1988-06-01

    This report provides criteria for evaluating the response of personnel dosimeters to radiation at nonperpendicular incidence. The US Department of Energy Laboratory Accreditation Program (DOELAP) ensures that dosimetry systems at DOE facilities meet acceptable standards for precision and accuracy. In the past, these standards were limited to tests for system variability, energy dependence, and level of detection. The proposed criteria will broaden the scope of DOELAP to include the angular response of personnel dosimeters. Because occupational exposures in the workplace are rarely due to radiation from only one direction, dosimeters must accurately assign individual dose equivalent from irradiation at any forward angle of incidence. Including an angular response criterion in DOELAP would improve the quality of personnel monitoring provided that the criterion is developed from appropriate dose quantities. This report provides guidance for assigning individual dose equivalents for radiation fields at nonperpendicular incidence to the dosimeter. 21 refs., 10 figs., 10 tabs.

  11. Pharmacological effects of Radix Angelica Sinensis (Danggui) on cerebral infarction

    PubMed Central

    2011-01-01

    Radix Angelica Sinensis, the dried root of Angelica sinensis (Danggui), is a herb used in Chinese medicine to enrich blood, promote blood circulation and modulate the immune system. It is also used to treat chronic constipation of the elderly and debilitated as well as menstrual disorders. Research has demonstrated that Danggui and its active ingredients, as anti-arthrosclerotic, anti-hypertensive, antioxidant anti-inflammatory agents which would limit platelet aggregation, are effective in reducing the size of cerebral infarction and improving neurological deficit scores. PMID:21867503

  12. An embryonic transcriptome of the pulmonate snail Radix balthica.

    PubMed

    Tills, Oliver; Truebano, Manuela; Rundle, Simon

    2015-12-01

    The pond snail, Radix balthica (Linnaeus 1758), is an emerging model species within ecological developmental biology. While its development has been characterised in detail, genomic resources for embryonic stages are lacking. We applied Illumina MiSeq RNA-seq to RNA isolated from pools of embryos at two points during development. Embryos were cultured in either the presence or absence of predator kariomones to increase the diversity of the transcripts assembled. Sequencing produced 47.2M paired-end reads, assembled into 54,360 contigs of which 73% were successfully annotated. This transcriptome provides an invaluable resource to build a mechanistic understanding of developmental plasticity. PMID:26297600

  13. The LLNL CR-39 personnel neutron dosimeter

    SciTech Connect

    Hankins, D.E.; Homann, S.; Westermark, J.

    1987-09-29

    We developed a personnel neutron dosimetry system based on the electrochemical etching of CR-39 plastic at elevated temperatures. The doses obtained using this dosimeter system are more accurate than those obtained using other dosimetry systems, especially when varied neutron spectra are encountered. This CR-39 dosimetry system does not have the severe energy dependence that exists with albedo neutron dosimeters or the fading and reading problems encountered with NTA film. 3 refs., 4 figs.

  14. Nuclear accident dosimeter processing with attenuation filters

    SciTech Connect

    Gunter, R.J.

    1994-05-01

    An evaluation of the Martin Marietta Energy Systems, Inc., Personnel Nuclear Accident Dosimeters was undertaken to determine if they could meet DOE 5480.11 requirements for photon dose assessment. Dosimeters were irradiated with a {sup 137}Cs source to doses ranging from 0.5 to 10,000 rad and processed using transmission filters to prevent photomultiplier tube saturation. Dose equivalent responses were found to meet the requirements using dosimeter reader number 55. Use of reader number 11 revealed a problem with current procedures. While performing a normal calibration with transmission filters in place it was discovered that there was a high noise component in the calibration signal, resulting in a poor calibration. Dosimeters processed with reader number 11 using a 1% transmission filter determined element 3 response 30% below expectations. The low element 3 response resulted in a significantly lower dose calculation for affected dosimeters. Another factor affecting overall response was an excessive supralinearity correction applied to dosimeters exposed between 100 and 1,000 rad.

  15. Radix Achyranthis Bidentatae improves learning and memory capabilities in ovariectomized rats.

    PubMed

    Wang, Yuefen; Xu, Ya; Pan, Yanshu; Li, Weihong; Zhang, Wei; Liu, Yang; Jia, Jing; Li, Pengtao

    2013-06-25

    Kidney-tonifying recipe can reduce the accumulation of advanced glycation end products, prevent neuronal degeneration and improve cognitive functions in ovariectomized rats. Radix Achyranthis Bidentatae alcohol extracts may dose-dependently inhibit non-enzymatic saccharification in vitro. This study aimed to examine the effect of Radix Achyranthis Bidentatae on advanced glycation end products and on learning and memory capabilities in ovariectomized rats. Ovariectomized rats were treated with Radix Achyranthis Bidentatae alcohol extracts (containing 1.5 g/kg crude drug) or 0.1% aminoguanidine for 12 weeks and behavioral testing was performed with the Y-electrical maze. This test revealed that Radix Achyranthis Bidentatae and aminoguanidine could improve the learning and memory capabilities of ovariectomized rats. Results of competitive enzyme-linked immunosorbent assay showed that treatment with Radix Achyranthis Bidentatae or aminoguanidine reduced the accumulation of advanced glycation end products in the frontal cortex of ovariectomized rats, while increasing content in the blood and urine. Biochemical tests showed that treatment with Radix Achyranthis Bidentatae or aminoguanidine decreased superoxide dismutase activity in the serum and frontal cortex, and increased serum levels of glutathione peroxidase in ovariectomized rats. In addition, there was no apparent effect on malondialdehyde levels. These experimental findings indicate that Radix Achyranthis Bidentatae inhibits production of advanced glycation end products and its accumulation in brain tissue, and improves learning and memory capabilities in ovariectomized rats. These effects may be associated with an anti-oxidative action of the extract. PMID:25206461

  16. [Safety and risk factor analysis on Polygoni Multiflori Radix base on ancient traditional Chinese medicine literatures].

    PubMed

    Song, Hai-bo; Du, Xiao-xi; Guo, Xiao-xin; Ren, Jing-tian; Yang, Le; Pang, Yu

    2015-03-01

    Traditional Chinese medicine Polygoni Multiflori Radix is dried roots of Polygonaceae Polygortum multiflorum Thunb. Its clinical application records were first discovered in literatures of the Tang dynasty. The origins, efficacy, toxicity, processing and taboos of Polygoni Multiflori Radix have been discussed in many ancient herb literatures. In recent years, with the increase in the public awareness in health, Polygoni Multiflori Radix admits preparations have been more widely applied in the treatment and prevention of diseases. However, there have been more and more reports about Polygoni Multiflori Radix induced liver injury, the safety of Polygoni Multiflori Radix has increasingly attracted attention of the society. In this paper, the authors summarized and analyzed the toxicity and medication risk factors of Polygoni Multiflori Radix recorded in ancient herb literatures, and proposed that more attention shall be given to the effect of the planting and processing methods on the components and toxicity of Polygoni Multiflori Radix in safety studies, which provides clues for the further studies. PMID:26087568

  17. [Research on spectral reflectance characteristics for Glycyrrhizae Radix].

    PubMed

    Li, Hui; Xie, Cai-Xiang; Li, Xiao-Jin; Wen, Mei-Jia; Jia, Guang-Lin; Shi, Ming-Hui; Guo, Bao-Lin; Jia, Xiao-Guang

    2014-02-01

    In order to study the spectral reflectance differences of Glycyrrhizae Radix under different growth conditions and lay the foundation for quantitative monitoring of Glycyrrhizae Radix remote sensing images, spectra of Glycyrrhiza species under different growth period and different varieties and different regions were measured by a portable spectrometer. The results showed that the reflectivity of annual G. uralensis was obviously higher than that of the two years plant in the visible light band own to the contents of crown layer chlorophyll. The reflectivity of two years G. pallidiflora was higher than that of G. uralensis in the near infrared band own to the leaf area index and the content of leaf water. The red edge spectrum of annual plant fluctuated largely than that of two years plant due to vegetation coverage and leaf area index. G. pallidiflora grew well than G. uralensis. Under different regions of the Glycyrrhiza species, spectral data analysis showed that within a certain range, the average annual precipitation and average annual evaporation were the major factors to affect the differences of Glycyrrhiza species spectral data under different regions owe to the leaf water content, the higher leaf water content, the lower spectral reflectance. The principal component analysis and continuum-removed method of the spectral data under different regions found that, within a certain range, the average annual precipitation and average annual evaporation were the major factors caused by the differences of Glycyrrhiza species spectral data under the different regions, Glycyrrhiza species spectral similarity related to the spatial distance. PMID:24946542

  18. [Simultaneous analysis of ginsenosides of various ginseng radix by HPLC].

    PubMed

    Samukawa, K; Yamashita, H; Matsuda, H; Kubo, M

    1995-03-01

    A simultaneous analysis of ginsenosides in Panax ginseng by high performance liquid chromatography recently established by us was applied to the analysis of various Ginseng Radix. The contents of ginsenosides in P. ginseng were examined according to the differences of the growth year, the used part of the plant, the method of processing and the cultivated location. In the case of P. ginseng cultivated in Nagano, Japan, the ratio (total ginsenosides content/total dry root weight) increases annually for three years. And it decreased at the fourth year and increases again at the fifth and the sixth years. Concerning the distribution of ginsenosides in the parts of the plant, they were contained at the highest level in a lateral root and in succession, in a rhizome > in a root hair > in a main root. They were also distributed much richer at periderm than at phloem or at xylem of a main root. The contents of panaxadiol- and panaxatriol-saponins gradually increase with the growth year, whereas an oleananesaponin, ginsenoside-Ro, drastically increases at the sixth year and goes to 15-fold, which suggests that the content of ginsenoside-Ro needs to be estimated much more when Ginseng Radix is evaluated. The fact that the processing for preparation of Red Ginseng increases the total content of saponins was clearly revealed by the present study. The highest contents of saponins among Red Ginsengs (all 6-year-old) were observed in ones prepared in Korea, and in Japan > in China, successively. PMID:7738782

  19. Efficient hardware implementation of 3X for radix-8 encoding

    NASA Astrophysics Data System (ADS)

    Ruiz, G. A.; Granda, Mercedes

    2007-05-01

    Several commercial processors have selected the radix-8 multiplier architecture to increase their speed, thereby reducing the number of partial products. Radix-8 encoding reduces the digit number length in a signed digit representation. Its performance bottleneck is the generation of the term 3X, also referred to as hard multiple. This term is usually computed by an adding and shifting operation, 3X=2X+X, in a high-speed adder. In a 2X+X addition, close full adders share the same input signal. This property permits simplified algebraic expressions associated to a 3X operation other than in a conventional addition. This paper shows that the 3X operation can be expressed in terms of two signals, H i and K i, functionally equivalent to two carries. Hi and Ki are computed in parallel using architectures which lead to an area and speed efficient implementation. For the purposes of comparison, implementation based on standard-cells of conventional adders has been compared with the proposed circuits based on these H i and K i signals. As a result, the delay of proposed serial scheme is reduced by roughly 67% without additional cost in area, the delay and area of the carry look-ahead scheme is reduced by 20% and 17%, and that of the parallel prefix scheme is reduced by 26% and 46%, respectively.

  20. Pharmacokinetic Evaluation of Clozapine in Concomitant Use of Radix Rehmanniae, Fructus Schisandrae, Radix Bupleuri, or Fructus Gardeniae in Rats.

    PubMed

    Tian, Dan-Dan; Wang, Wei; Wang, Hua-Ning; Sze, Stephen Cho Wing; Zhang, Zhang-Jin

    2016-01-01

    Radix Rehmanniae, Fructus Schisandrae, Radix Bupleuri, and Fructus Gardeniae are often used alongside with clozapine (CLZ) for schizophrenia patients in order to reduce side effects and enhance therapeutic efficacy. However, worse outcomes were observed raising concern about a critical issue, herb-drug interactions, which were rarely reported when antipsychotics were included. This study aims to determine whether the concomitant use of these herbal medicines affects the pharmacokinetic characteristics of CLZ in rat models. Rats were given a single or multiple intraperitoneal injections of 10 mg/kg CLZ, either alone or with individual herbal water extracts administered orally. CLZ and its two inactive metabolites, norclozapine and clozapine N-oxide, were determined by high-performance liquid chromatography/tandem mass spectrometry. In the acute treatment, the formation of both metabolites was reduced, while no significant change was observed in the CLZ pharmacokinetics for any of the herbal extracts. In the chronic treatment, none of the four herbal extracts significantly influenced the pharmacokinetic parameters of CLZ and its metabolites. Renal and liver functions stayed normal after the 11-day combined use of herbal medicines. Overall, the four herbs had limited interaction effect on CLZ pharmacokinetics in the acute and chronic treatment. Herb-drug interaction includes both pharmacokinetic and pharmacodynamic mechanisms. This result gives us a hint that pharmacodynamic herb-drug interaction, instead of pharmacokinetic types, may exist and need further confirmation. PMID:27240333

  1. Preparation and characterization of Ag-cluster in poly(methylmethacrylate)

    SciTech Connect

    Yanagihara, Naohisa; Ishii, Yoshitaka; Kawase, Takanori; Kaneko, Toshimare; Horie, Hisashi; Hara, Toru

    1997-09-01

    Solid sols of silver in poly(methylmethacrylate), Ag/PMMA, were prepared by bulk polymerization of methyl methacrylate (MMA) with benzoyl peroxide (BPO) as an initiator in the presence of silver(I) trifluoroacetate. Ag/PMMAs were characterized by visible spectroscopy. Effects of the concentration of initiator, the concentration of silver(I) complex and the heat-treatment time on the formation of silver cluster were studied in detail.

  2. Quantitative determination and pattern recognition analyses of bioactive marker compounds from Dipsaci Radix by HPLC.

    PubMed

    Zhao, Bing Tian; Jeong, Su Yang; Moon, Dong Cheul; Son, Kun Ho; Son, Jong Keun; Woo, Mi Hee

    2013-11-01

    In this study, quantitative and pattern recognition analyses were developed using HPLC/UV for the quality evaluation of Dipsaci Radix. For quantitative analysis, five major bioactive compounds were assessed. The separation conditions employed for HPLC/UV were optimized using ODS C18 column (250 × 4.6 mm, 5 μm) with a gradient of acetonitrile and water as the mobile phase at a flow rate of 1.0 mL/min and a detection wavelength of 212 nm. These methods were fully validated with respect to linearity, accuracy, precision, recovery, and robustness. The HPLC/UV method was applied successfully to the quantification of five major compounds in the extract of Dipsaci Radix. The HPLC analytical method for pattern recognition analysis was validated by repeated analysis of 17 Dipsaci Radix and four Phlomidis Radix samples. The results indicate that the established HPLC/UV method is suitable for quantitative analysis. PMID:23877237

  3. [Optimization of extraction process of compound Clematidis Radix spray by support vector machine].

    PubMed

    Zhao, Li; Li, Hui; Liu, Yi-fan; Fu, Yan; Liu, Yu-ling; Zhang, Xiao-li

    2015-04-01

    L9 (3(4)) orthogonal experiment was used to design the extraction technology of compound Clematidis Radix spray. Weight coefficients of active ingredients and dry extract rate were solved by information entropy. Support vector machine (SVM) was established and the model parameters were optimized through the genetic algorithm. Grid search algorithm was used for optimization of extraction technology of Clematidis Radix spray. The optimal extraction technology was to extract Clematidis Radix spray in water with 6 times the weight of herbal medicine for 3 times, with 2 h once. Bias of value between real and predicted by SVM was 1.23%. SVM was compared with traditional intuitive analysis of orthogonal design. It indicates that the new method used to optimize the extraction parameters of compound Clematidis Radix spray is more accurate and reliable. PMID:26281549

  4. A hyperglycemic silkworm model for evaluating hypoglycemic activity of Rehmanniae Radix, an herbal medicine.

    PubMed

    Matsumoto, Yasuhiko; Sekimizu, Kazuhisa

    2016-02-01

    Silkworm shows hyperglycemia after intake of diet containing large amount of glucose. The hyperglycemic silkworm model is useful for evaluation of anti-diabetic drugs. A hot water extract of Rehmanniae Radix, an herbal medicine, showed hypoglycemic effect against the hyperglycemic silkworms. This method is applicable for quick and simple evaluation of the hypoglycemic activities of different batches of Rehmanniae Radix. Our findings suggest that silkworms have a lot of merit as experimental animals for evaluation of various herbal medicines. PMID:26902904

  5. Thermal stability of kudzu root (Pueraria Radix) isoflavones as additives to beef patties.

    PubMed

    Kumari, S; Raines, J M; Martin, J M; Rodriguez, J M

    2015-03-01

    Kudzu root, Pueraria radix, extracts are a rich source of isoflavones. This study investigates the thermal stability of Pueraria radix extracts as a natural nutraceutical supplement in beef patties. The extract contained puerarin, diadzin, genistin, ononin, daidzein, glycitein, calycosin, genistein, formononetin and biochanin A; however, puerarin, daidzein and glycitein were the main components. The isoflavones concentrations in the spiked beef patties with kudzu root extracts were unaffected by cooking. PMID:25745227

  6. PNNL Results from 2009 Silene Criticality Accident Dosimeter Intercomparison Exercise

    SciTech Connect

    Hill, Robin L.; Conrady, Matthew M.

    2010-06-30

    This document reports the results of testing of the Hanford Personnel Nuclear Accident Dosimeter (PNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on October 13, 14, and 15, 2009.

  7. Environmental dosimeter of the thermoluminescent type

    DOEpatents

    Eichner, F.N.; Kocher, L.F.

    1974-01-29

    A dosimeter for accurately monitoring normally low-energy radiation including a thermoluminescent CaF phosphor enclosed within a tantalum capsule is described. The tantalum acts as a filter to weaken the measured dose due to photons having energies below about 0.2 MeV. Tantalum end caps are maintained on the capsule body by a polyolefin sheath formed from heat-contractable tubing. After exposing the dosimeter to environmental radiation, it is placed in a shielded chamber for about 24 h and subsequently annealed at about 80 deg C to release radiation energy accumulated in low-temperature traps. The dosimeter is then disassembled and the phosphors photometrically read at temperatures about 50 deg C to determine the absorbed radiation dose. (Official Gazette)

  8. System for use with solid state dosimeter

    DOEpatents

    Miller, S.D.; McDonald, J.C.; Eichner, F.N.; Tomeraasen, P.L.

    1990-09-04

    The present invention constitutes a system for determining the amounts of ionizing radiation to which dosimeters using thermoluminescent materials have been exposed. In accordance with this system, the thermoluminescent materials which comprise the dosimeters are first cooled by contact with a cryogenic substance such as liquefied nitrogen. The thermoluminescent materials are then optically stimulated by exposure to ultraviolet light. Thereafter, the amounts of visible light emitted by the thermoluminescent materials are detected and counted as the materials are allowed to warm up to room temperature. The amounts of luminescence exhibited by the materials are related to radiation exposure and provide a sensitive measure of radiation dosage. It has been discovered that the above procedure is most effective when heavily doped thermoluminescent materials are used and that the procedure allows many useful plastic materials to now be employed in dosimeter constructions. 3 figs.

  9. System for use with solid state dosimeter

    DOEpatents

    Miller, Steven D.; McDonald, Joseph C.; Eichner, Fred N.; Tomeraasen, Paul L.

    1990-01-01

    The present invention constitutes a system for determining the amounts of ionizing radiation to which dosimeters using thermoluminescent materials have been exposed. In accordance with this system, the thermoluminescent materials which comprise the dosimeters are first cooled by contact with a cryogenic substance such as liquified nitrogen. The thermoluminescent materials are then optically stimulated by exposure to ultraviolet light. Thereafter, the amounts of visible light emitted by the thermoluminescent materials are detected and counted as the materials are allowed to warm up to room temperature. The amounts of luminescence exhibited by the materials are related to radiation exposure and provide a sensitive measure of radiation dosage. It has been discovered that the above procedure is most effective when heavily doped thermoluminescent materials are used and that the procedure allows many useful plastic materials to now be employed in dosimeter constructions.

  10. Do saccharide doped PAGAT dosimeters increase accuracy?

    NASA Astrophysics Data System (ADS)

    Berndt, B.; Skyt, P. S.; Holloway, L.; Hill, R.; Sankar, A.; De Deene, Y.

    2015-01-01

    To improve the dosimetric accuracy of normoxic polyacrylamide gelatin (PAGAT) gel dosimeters, the addition of saccharides (glucose and sucrose) has been suggested. An increase in R2-response sensitivity upon irradiation will result in smaller uncertainties in the derived dose if all other uncertainties are conserved. However, temperature variations during the magnetic resonance scanning of polymer gels result in one of the highest contributions to dosimetric uncertainties. The purpose of this project was to study the dose sensitivity against the temperature sensitivity. The overall dose uncertainty of PAGAT gel dosimeters with different concentrations of saccharides (0, 10 and 20%) was investigated. For high concentrations of glucose or sucrose, a clear improvement of the dose sensitivity was observed. For doses up to 6 Gy, the overall dose uncertainty was reduced up to 0.3 Gy for all saccharide loaded gels compared to PAGAT gel. Higher concentrations of glucose and sucrose deteriorate the accuracy of PAGAT dosimeters for doses above 9 Gy.

  11. Solid state neutron dosimeter for space applications

    SciTech Connect

    Nagarkar, V.; Entine, G.; Stoppel, P.; Cirignano, L. ); Swinehart, P. )

    1992-08-01

    One of the most important contributions to the radiation exposure of astronauts engaged in space flight is the significant flux of high energy neutrons arising from both primary and secondary sources of ionizing radiation. Under NASA sponsorship, the authors are developing a solid state neutron sensor capable of being incorporated into a very compact, flight instrument to provide high quality real time measurement of this important radiation flux. The dosimeter uses a special, high neutron sensitivity, PIN diode that is insensitive t the other forms of ionizing radiation. The dosimeter will have the ability to measure and record neutron dose over a range of 50 microgray to tens of milligrays (5 millirads to several rads) over a flight of up to 30 days. the performance characteristics of the PIN diode with a detailed description of the overall dosimeter is presented. in this paper.

  12. Anti-inflammatory and cytotoxic effects of methanol, ethanol, and water extracts of Angelicae Dahuricae Radix.

    PubMed

    Wang, Myeong-Hyeon; Jeong, Su-Hyeon; Guo, Huifang; Park, Jun-Beom

    2016-01-01

    Angelicae Dahuricae Radix has been used for the treatment of headaches, rhinitis, and colds in traditional medicine. Methanol, ethanol, and water extracts of Angelicae Dahuricae Radix were collected. A statistically significant reduction in the cellular viability of the mouse leukemic monocyte macrophage cell line was noted after treatment with water extracts of Angelicae Dahuricae Radix. Stimulation with lipopolysaccharides (LPS) for 24 h led to a robust increase in nitric oxide production, but Angelicae Dahuricae Radix at 400 μg/mL concentration significantly suppressed nitric oxide produced by the LPS-stimulated RAW 264.7 cells in 70% ethanol, absolute ethanol, 70% methanol, absolute methanol, and boiling water groups (P < 0.05). Pretreatment with absolute ethanol extract of Angelicae Dahuricae Radix suppressed the LPS-stimulated inducible nitric oxide synthase, interleukin-1β, and cycloxygenase-2 expression. Angelicae Dahuricae Radix showed significant cytotoxic effects on the human adenocarcinoma cell line and keratin-forming cell line. (J Oral Sci 58, 125-131, 2016). PMID:27021549

  13. Mechanisms of improvement of intestinal transport of baicalin and puerarin by extracts of Radix Angelicae Dahuricae.

    PubMed

    Liang, Xin-Li; Zhang, Jing; Zhao, Guo-Wei; Li, Zhe; Luo, Yun; Liao, Zheng-Gen; Yan, Dong-Mei

    2015-02-01

    Radix Angelicae Dahuricae is the dried root of Angelicae Dahurica (Fisch.ex Hoffm.)Benth.et Hook.f. var.formosana (Boiss.) Shan et Yuan (Fam.Umbelliferae). The total coumarins (Cou) and volatile oil (VO) were main active components that drived from Radix Angelicae Dahuricae. Our previous studies have shown that Cou and VO could increase intestinal absorption for transmucosal drug delivery with unknown mechanism. The aim of this study was to investigate the molecular mechanism of Radix Angelicae Dahuricae for improving drug intestinal transport. Caco-2 cell model was used to study the effect of Radix Angelicae Dahurica on transepithelial electrical resistance. Western blot was used to study its effect on the expression of the actin and ZO-1, tight junction proteins. The effect of Radix Angelicae Dahurica on the expression of P-gp protein was investigated using flow cytometry. VO (0.036-2.88 μL/mL) and Cou (0.027-0.54 mg/mL) caused a reversible, time- and dose-dependent decrease in transepithelial electrical resistance. VO and/or Cou could inhibit the expression of the tight junction protein, ZO-1 and actin. VO and/or Cou also could inhibit the expression of P-gp. These data suggested that Radix Angelicae Dahurica increased cell permeability by affecting the expression of actin, ZO-1 or P-gp, opening the tight junction or inhibiting the efflux induced by P-gp. PMID:25312586

  14. Transcriptomic analysis of Pseudostellariae Radix from different fields using RNA-seq.

    PubMed

    Hua, Yujiao; Wang, Shengnan; Liu, Zixiu; Liu, Xunhong; Zou, Lisi; Gu, Wei; Luo, Yiyuan; Liu, Juanxiu

    2016-08-15

    Pseudostellariae Radix is an important traditional Chinese medicine (TCM), which is consumed commonly for its positive health effects. However, a lack of transcriptomic and genomic information hinders research on Pseudostellariae Radix. Here, high-throughput RNA sequencing (RNA-seq) was employed for the de novo assembly to analyze the transcriptome in Pseudostellariae Radix, finding significantly differentially expressed genes in this TCM from different fields based on RNA-seq and bioinformatic analysis. A total of 146,408,539 paired-end reads were generated and assembled into 89,857 unigenes with an average length of 862bp. All of the assembly unigenes were annotated by running BLASTx and BLASTn similarity searches on the Non-redundant nucleotide database (NT), the Non-redundant protein database (NR), Swiss-Prot, Cluster of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Interpro. On the basis of bioinformatic analysis and the expression profiles for Pseudostellariae Radix, 29 significantly differentially expressed genes were identified, which provides the basic information for exploring the molecular mechanisms that determine the quality of Pseudostellariae Radix from different fields. The expression levels of 29 genes were validated by real-time quantitative PCR (RT-qPCR). This is the first study to sample Pseudostellariae Radix, which provides an invaluable resource for understanding the genome of this herb. PMID:27125225

  15. Automating the personnel dosimeter monitoring program

    SciTech Connect

    Compston, M.W.

    1982-12-01

    The personnel dosimetry monitoring program at the Portsmouth uranium enrichment facility has been improved by using thermoluminescent dosimetry to monitor for ionizing radiation exposure, and by automating most of the operations and all of the associated information handling. A thermoluminescent dosimeter (TLD) card, worn by personnel inside security badges, stores the energy of ionizing radiation. The dosimeters are changed-out periodically and are loaded 150 cards at a time into an automated reader-processor. The resulting data is recorded and filed into a useful form by computer programming developed for this purpose.

  16. Fiber optic dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2014-08-01

    A small dimension, real-time readout dosimeter is desirable for specific applications in medical physics as for example, dose measurement in prostate brachytherapy. This particular radiotherapy procedure consists in the permanent deposition of low energy, low-dose and low-dose rate small sized radioactive seeds. We developed a scintillating fiber optic based dosimeter suitable for in-vivo, real-time low dose and low dose rate measurements. Due to the low scintillation light produced in the scintillating fiber, a high sensitive and high gain light detector is required. The Silicon Photomultipliers are an interesting option that allowed us to obtain good results in our studies.

  17. Highland cattle and Radix labiata, the hosts of Fascioloides magna

    PubMed Central

    2014-01-01

    Background Fascioloides magna is a pathogenic fluke introduced to Europe ca 140 years ago. As it is spreading over the continent, new intermediate and definitive hosts might be involved in transmission of the parasite. In Europe, several studies reported potential new intermediate snail hosts (Radix spp.) for F. magna, and also several cases of fascioloidosis of wild and domestic animals were published. However, the data based on molecular and histological analyses confirming these findings remained unreported. This study aims to refer to unique findings of F. magna in European snails and domestic animals (the first observation in the Czech Republic in the last 30 years) and demonstrate the use of molecular techniques in determination of F. magna. Results Two snails of R. labiata naturally infected with F. magna were found; mature cercariae and daughter rediae were observed. Maturity of cercariae was checked by histological methods, however, their ability to encyst was not confirmed. Co-infection of F. magna and Fasciola hepatica in the liver of two highland cattle bulls was proved. Adult fasciolid flukes producing eggs were found in the liver pseudocysts (F. magna) and the bile ducts (F. hepatica). Identification of intermediate hosts, intramolluscan stages, adult flukes and eggs was performed by sequencing the ITS2 region. Connection of F. magna pseudocysts with the gut (via the bile ducts) was not confirmed by means of histological and coprological examinations. Conclusions For the first time, Radix labiata was confirmed as the snail host for F. magna under natural conditions and, together with the finding of F. magna infection in cattle, we can expect further transmission of F. magna from wildlife to livestock in localities shared by these hosts. PMID:24517409

  18. Characterization of MOSFET dosimeter angular dependence in three rotational axes measured free-in-air and in soft-tissue equivalent material

    PubMed Central

    Koivisto, Juha; Kiljunen, Timo; Wolff, Jan; Kortesniemi, Mika

    2013-01-01

    When performing dose measurements on an X-ray device with multiple angles of irradiation, it is necessary to take the angular dependence of metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters into account. The objective of this study was to investigate the angular sensitivity dependence of MOSFET dosimeters in three rotational axes measured free-in-air and in soft-tissue equivalent material using dental photon energy. Free-in-air dose measurements were performed with three MOSFET dosimeters attached to a carbon fibre holder. Soft tissue measurements were performed with three MOSFET dosimeters placed in a polymethylmethacrylate (PMMA) phantom. All measurements were made in the isocenter of a dental cone-beam computed tomography (CBCT) scanner using 5º angular increments in the three rotational axes: axial, normal-to-axial and tangent-to-axial. The measurements were referenced to a RADCAL 1015 dosimeter. The angular sensitivity free-in-air (1 SD) was 3.7 ± 0.5 mV/mGy for axial, 3.8 ± 0.6 mV/mGy for normal-to-axial and 3.6 ± 0.6 mV/mGy for tangent-to-axial rotation. The angular sensitivity in the PMMA phantom was 3.1 ± 0.1 mV/mGy for axial, 3.3 ± 0.2 mV/mGy for normal-to-axial and 3.4 ± 0.2 mV/mGy for tangent-to-axial rotation. The angular sensitivity variations are considerably smaller in PMMA due to the smoothing effect of the scattered radiation. The largest decreases from the isotropic response were observed free-in-air at 90° (distal tip) and 270° (wire base) in the normal-to-axial and tangent-to-axial rotations, respectively. MOSFET dosimeters provide us with a versatile dosimetric method for dental radiology. However, due to the observed variation in angular sensitivity, MOSFET dosimeters should always be calibrated in the actual clinical settings for the beam geometry and angular range of the CBCT exposure. PMID:23520268

  19. Characterization of MOSFET dosimeter angular dependence in three rotational axes measured free-in-air and in soft-tissue equivalent material.

    PubMed

    Koivisto, Juha; Kiljunen, Timo; Wolff, Jan; Kortesniemi, Mika

    2013-09-01

    When performing dose measurements on an X-ray device with multiple angles of irradiation, it is necessary to take the angular dependence of metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters into account. The objective of this study was to investigate the angular sensitivity dependence of MOSFET dosimeters in three rotational axes measured free-in-air and in soft-tissue equivalent material using dental photon energy. Free-in-air dose measurements were performed with three MOSFET dosimeters attached to a carbon fibre holder. Soft tissue measurements were performed with three MOSFET dosimeters placed in a polymethylmethacrylate (PMMA) phantom. All measurements were made in the isocenter of a dental cone-beam computed tomography (CBCT) scanner using 5º angular increments in the three rotational axes: axial, normal-to-axial and tangent-to-axial. The measurements were referenced to a RADCAL 1015 dosimeter. The angular sensitivity free-in-air (1 SD) was 3.7 ± 0.5 mV/mGy for axial, 3.8 ± 0.6 mV/mGy for normal-to-axial and 3.6 ± 0.6 mV/mGy for tangent-to-axial rotation. The angular sensitivity in the PMMA phantom was 3.1 ± 0.1 mV/mGy for axial, 3.3 ± 0.2 mV/mGy for normal-to-axial and 3.4 ± 0.2 mV/mGy for tangent-to-axial rotation. The angular sensitivity variations are considerably smaller in PMMA due to the smoothing effect of the scattered radiation. The largest decreases from the isotropic response were observed free-in-air at 90° (distal tip) and 270° (wire base) in the normal-to-axial and tangent-to-axial rotations, respectively. MOSFET dosimeters provide us with a versatile dosimetric method for dental radiology. However, due to the observed variation in angular sensitivity, MOSFET dosimeters should always be calibrated in the actual clinical settings for the beam geometry and angular range of the CBCT exposure. PMID:23520268

  20. A new type of extremity dosimeter

    NASA Astrophysics Data System (ADS)

    Uchrin, György

    1980-09-01

    A three element sandwich type dosimeter has been developed. The beta element is LiF cold pressed to an Al disc the response of which follows the energy dependence of the true skin beta dose for Emax⩾ 0.2 MeV. Filtered LiF hot pressed chips measure gamma dose and indicate the radiation quality.

  1. Response characteristics of selected personnel neutron dosimeters

    SciTech Connect

    McDonald, J.C.; Fix, J.J.; Hadley, R.T.; Holbrook, K.L.; Yoder, R.C.; Roberson, P.L.; Endres, G.W.R.; Nichols, L.L.; Schwartz, R.B.

    1983-09-01

    Performance characteristics of selected personnel neutron dosimeters in current use at Department of Energy (DOE) facilities were determined from their evaluation of neutron dose equivalent received after irradiations with specific neutron sources at either the National Bureau of Standards (NBS) or the Pacific Northwest Laboratory (PNL). The characteristics assessed included: lower detection level, energy response, precision and accuracy. It was found that when all of the laboratories employed a common set of calibrations, the overall accuracy was approximately +-20%, which is within uncertainty expected for these dosimeters. For doses above 80 mrem, the accuracy improved to better than 10% when a common calibration was used. Individual differences found in this study may reflect differences in calibration technique rather than differences in the dose rates of actual calibration standards. Second, at dose rates above 100 mrem, the precision for the best participants was generally below +-10% which is also within expected limits for these types of dosimeters. The poorest results had a standard deviation of about +-25%. At the lowest doses, which were sometimes below the lower detection limit, the precision often approached or exceeded +-100%. Third, the lower level of detection for free field /sup 252/Cf neutrons generally ranged between 20 and 50 mrem. Fourth, the energy dependence study provided a characterization of the response of the dosimeters to neutron energies far from the calibration energy. 11 references, 22 figures, 26 tables.

  2. Investigating hydrogel dosimeter decomposition by chemical methods

    NASA Astrophysics Data System (ADS)

    Jordan, Kevin

    2015-01-01

    The chemical oxidative decomposition of leucocrystal violet micelle hydrogel dosimeters was investigated using the reaction of ferrous ions with hydrogen peroxide or sodium bicarbonate with hydrogen peroxide. The second reaction is more effective at dye decomposition in gelatin hydrogels. Additional chemical analysis is required to determine the decomposition products.

  3. Pen Ink as an Ultraviolet Dosimeter

    ERIC Educational Resources Information Center

    Downs, Nathan; Turner, Joanna; Parisi, Alfio; Spence, Jenny

    2008-01-01

    A technique for using highlighter ink as an ultraviolet dosimeter has been developed for use by secondary school students. The technique requires the students to measure the percentage of colour fading in ink drawn onto strips of paper that have been exposed to sunlight, which can be calibrated to measurements of the ultraviolet irradiance using…

  4. Compton effect thermally activated depolarization dosimeter

    DOEpatents

    Moran, Paul R.

    1978-01-01

    A dosimetry technique for high-energy gamma radiation or X-radiation employs the Compton effect in conjunction with radiation-induced thermally activated depolarization phenomena. A dielectric material is disposed between two electrodes which are electrically short circuited to produce a dosimeter which is then exposed to the gamma or X radiation. The gamma or X-radiation impinging on the dosimeter interacts with the dielectric material directly or with the metal composing the electrode to produce Compton electrons which are emitted preferentially in the direction in which the radiation was traveling. A portion of these electrons becomes trapped in the dielectric material, consequently inducing a stable electrical polarization in the dielectric material. Subsequent heating of the exposed dosimeter to the point of onset of ionic conductivity with the electrodes still shorted through an ammeter causes the dielectric material to depolarize, and the depolarization signal so emitted can be measured and is proportional to the dose of radiation received by the dosimeter.

  5. Occlusion of an Intraosseous Arteriovenous Malformation With Percutaneous Injection of Polymethylmethacrylate

    SciTech Connect

    Ierardi, Anna Maria; Mangini, Monica; Vaghi, Massimo; Cazzulani, Alberto; Mattassi, Raul; Carrafiello, Gianpaolo

    2011-02-15

    Primary intraosseous arteriovenous malformations are rare. Many minimally invasive procedures can be considered preoperative steps and/or definitive treatment. The case reported regards a young woman with a voluminous arteriovenous extratroncular infiltrating malformation of the humerus. She underwent several treatments, but none of them was completely occlusive. The last treatment consisted of direct percutaneous puncture of the intraosseous alteration and injection of polymethylmethacrylate (PMMA), which is normally used in percutaneous vertebroplasty. We obtained complete occlusion of the humerus lytic lesion. To the best of our knowledge, this represents the first case of intraosseous AVM treated by percutaneous injection of PMMA.

  6. Stress-induced wrinkling of sputtered SiO{sub 2} films on polymethylmethacrylate

    SciTech Connect

    Serrano, Justin R.; Xu Qinqin; Cahill, David G.

    2006-03-15

    Compressively stressed SiO{sub 2} films are deposited by rf magnetron sputtering onto polymethylmethacrylate- (PMMA) coated Si substrates. The oxide film roughens by wrinkling during deposition; wrinkling is enabled by the viscous flow of the PMMA layer. The nanoscale lateral length scale of the wrinkling, {approx}120 nm, is established during the first few nanometers of film deposition and is controlled by the thickness and stress of the SiO{sub 2} film at the onset of the instability. Continued deposition of SiO{sub 2} leads to a rapid increase and then saturation of the rms roughness at {approx}5 nm.

  7. Reversible patterning of poly(methylmethacrylate) doped with disperse Red 1 by laser scanning

    SciTech Connect

    Tuma, J.; Lyutakov, O.; Huttel, I.; Slepicka, P.; Svorcik, V.

    2013-09-07

    Thin poly(methylmethacrylate) films doped by or covalently attached to disperse Red 1 acrylate (DR1) were patterned by laser scanning and simultaneous sample movement in confocal microscope. In both cases, periodical structure due to Marangoni effect is created. Modified polymers surfaces were analyzed by FTIR spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy. After first stage of patterning, second stage with sample movement in perpendicular direction was applied. Depending on the method of DR1 dotation fishnet structure is obtained or pattern structure disappears. In the latter case, reversibility of pattern formation and erasure by laser scanning was studied.

  8. Radix Ilicis Pubescentis total flavonoids ameliorates neuronal damage and reduces lesion extent in a mouse model of transient ischemic attack

    PubMed Central

    Miao, Ming-san; Guo, Lin; Li, Rui-qi; Zhang, Xiao-lei

    2016-01-01

    Flavonoids are a major component in the traditional Chinese medicine Radix Ilicis Pubescentis. Previous studies have shown that the administration of Radix Ilicis Pubescentis total flavonoids is protective in cerebral ischemia. However, to our knowledge, no studies have examined whether the total flavonoids extracted from Radix Ilicis Pubescentis prevent or ameliorate neuronal damage following transient ischemic attacks. Therefore, Radix Ilicis Pubescentis total flavonoids question and the potential underlying mechanisms. Thus, beginning 3 days before the induction of a mouse model of transient ischemic attack using tert-butyl hydroperoxide injections, mice were intragastrically administered 0.3, 0.15, or 0.075 g/kg of Radix Ilicis Pubescentis total flavonoids daily for 10 days. The results of spectrophotometric analyses demonstrated that Radix Ilicis Pubescentis total flavonoids enhanced oxygen free radical scavenging and reduced pathological alterations in the brain. Hematoxylin-eosin staining results showed that Radix Ilicis Pubescentis total flavonoids reduced hippocampal neuronal damage and cerebral vascular injury in this mouse model of transient ischemic attack. These results suggest that the antioxidant effects of Radix Ilicis Pubescentis total flavonoids alleviate the damage to brain tissue caused by transient ischemic attack. PMID:27127483

  9. [Comparative study on identification of Clematidis Radix et Rhizoma from different origins based on microstructure and NIRS method].

    PubMed

    Xu, Ya; Li, Hui; Feng, Xue-feng; Liu, Yu-ling; Zhang, Xiao-li

    2015-04-01

    Microscopic identification and NIRS methods were applied to identify Clematidis Radix et Rhizoma of two different origins. The results showed that both methods could identify the samples. NIRS could identify the two samples nondestructively, and provides a basis for establishment of a standard herbs radix clematidis NIRS fingerprint in the future. PMID:26281546

  10. Optimized hydrolysis and analysis of Radix Asparagi polysaccharide monosaccharide composition by capillary zone electrophoresis.

    PubMed

    Chen, Jiye; Yang, Feifei; Guo, Huaizhong; Wu, Fang; Wang, Xiaohuan

    2015-07-01

    Using orthogonal design, optimized conditions for the hydrolysis of the polysaccharide from Radix Asparagi were determined, as well as its monosaccharide composition. Optimized hydrolysis conditions were a temperature of 100°C in 1.5 M sulfuric acid solution for 5 h. The resulting monosaccharides were derivatized with 1-phenyl-3-methyl-5-pyrazolone, then separated by capillary zone electrophoresis in 40 mM sodium tetraborate buffer (pH 10.1), and detected by ultraviolet absorption at 245 nm. Results indicate that the polysaccharide from Radix Asparagi is composed of xylose, arabinose, glucose, rhamnose, mannose, galactose, glucuronic acid, and galacturonic acid, which differs from published findings. Moreover, xylose, glucuronic acid, and galacturonic acid have not been previously reported in Radix Asparagi polysaccharide. This method is simple, fast, and yields a highly efficient separation. As well, these findings can be applied to quality control of Radix Asparagi and for in-depth study of the biological activity of Radix Asparagi polysaccharide. PMID:25885471

  11. Photosynthetic Physiological Response of Radix Isatidis (Isatis indigotica Fort.) Seedlings to Nicosulfuron

    PubMed Central

    Ning, Na; Wen, Yinyuan; Dong, Shuqi; Yin, Meiqiang; Guo, Meijun; Wang, Binqiang; Feng, Lei; Guo, Pingyi

    2014-01-01

    Radix Isatidis (Isatis indigotica Fort.) is one of the most important traditional Chinese medicine plants. However, there is no suitable herbicide used for weed control in Radix Isatidis field during postemergence stage. To explore the safety of sulfonylurea herbicide nicosulfuron on Radix Isatidis (Isatis indigotica Fort.) seedlings and the photosynthetic physiological response of the plant to the herbicide, biological mass, leaf area, photosynthetic pigment content, photosynthetic rate, chlorophyll fluorescence characteristics, and P700 parameters of Radix Isatidis seedlings were analyzed 10 d after nicosulfuron treatment at 5th leaf stage in this greenhouse research. The results showed that biological mass, total chlorophyll, chlorophyll a, and carotenoids content, photosynthetic rate, stomatal conductance, PS II maximum quantum yield, PS II effective quantum yield, PS II electron transport rate, photochemical quenching, maximal P700 change, photochemical quantum yield of PS I, and PS I electron transport rate decreased with increasing herbicide concentrations, whereas initial fluorescence, quantum yield of non-regulated energy dissipation in PS II and quantum yield of non-photochemical energy dissipation due to acceptor side limitation in PS I increased. It suggests that nicosulfuron ≥1 mg L−1 causes the damage of chloroplast, PS II and PS I structure. Electron transport limitations in PS I receptor side, and blocked dark reaction process may be the main cause of the significantly inhibited growth and decreased photosynthetic rate of Radix Isatidis seedlings. PMID:25165819

  12. The figure-of-eight radix nasi flap for medial canthal defects.

    PubMed

    Seyhan, Tamer

    2010-09-01

    Basal cell carcinomas commonly involve the medial canthal region and reconstruction of medial canthal defects is a challenging problem in reconstructive surgery. A new axial pattern flap raised from radix nasi region has been successfully used for the medial canthal defects in eight patients in figure-of-eight manner. One of the ellipses of the figure of eight is the defect, the other is the radix nasi flap. The radix nasi flap with a dimension up to 25 mm is transposed to the defect based either on ipsilateral anastomosis of the dorsal nasal artery with angular artery (AA) or with the connection of its source artery (i.e. ophthalmic artery) if the AA is damaged. All flaps survived and no tumour recurrence was observed. The donor sites were closed primarily and hidden at the radix nasi crease in all cases. The radix nasi flap in figure-of-eight fashion is good alternative for defects of the medial canthal area in terms of attaining a suitable colour and texture and minimal surgical scars. PMID:20079658

  13. Clinical applications of 3-D dosimeters

    NASA Astrophysics Data System (ADS)

    Wuu, Cheng-Shie

    2015-01-01

    Both 3-D gels and radiochromic plastic dosimeters, in conjunction with dose image readout systems (MRI or optical-CT), have been employed to measure 3-D dose distributions in many clinical applications. The 3-D dose maps obtained from these systems can provide a useful tool for clinical dose verification for complex treatment techniques such as IMRT, SRS/SBRT, brachytherapy, and proton beam therapy. These complex treatments present high dose gradient regions in the boundaries between the target and surrounding critical organs. Dose accuracy in these areas can be critical, and may affect treatment outcome. In this review, applications of 3-D gels and PRESAGE dosimeter are reviewed and evaluated in terms of their performance in providing information on clinical dose verification as well as commissioning of various treatment modalities. Future interests and clinical needs on studies of 3-D dosimetry are also discussed.

  14. Potential antidepressant properties of Radix Polygalae (Yuan Zhi).

    PubMed

    Liu, P; Hu, Y; Guo, D-H; Wang, D-X; Tu, H-H; Ma, L; Xie, T-T; Kong, L-Y

    2010-08-01

    Radix Polygalae ("Yuan Zhi", the roots of Polygala tenuifolia Willd., YZ) is an important herb used in traditional Chinese medicine to mediate depression. The present study was designed to verify the antidepressant effects of the standardized YZ ethanol extract (YZE) and its four fractions YZ-30, YZ-50, YZ-70 and YZ-90 on the tail suspension (TST) and forced swimming test (FST). Furthermore, the standardization of the fractions obtained from the separation procedures was carried out by high-performance liquid chromatography (HPLC)-fingerprint. The YZ-50 fraction (Oligosaccharide esters--enriched, oral (200 mg/kg) showed a significant anti-immobility like effects. The data of YZ-50 on the corticosterone-induced injure of SH-SY5Y human neuroblastoma cell indicated that YZ-50 may have biological effects on neuroprotection. Proliferation of cell lines was assessed by dimethylthiazoldiphenyltetrazoliumbromide (MTT) and 5-bromo-2'-deoxyuridine (BrdU) incorporation assays. It was found that YZ-50 and its two bioactive compounds, 3,6'-di-o-sinapoyl-sucrose (DISS) and tenuifoliside A(TEA) showed protection activities in SY5Y cells from the lesion. By using bioassay-screening methods, our results indicate that the presence of oligosaccharide esters such as DISS and TEA in this herb may be responsible for the cytoprotective activity effects. PMID:20541923

  15. Neuroprotective and Cytotoxic Phthalides from Angelicae Sinensis Radix.

    PubMed

    Gong, Wenxia; Zhou, Yuzhi; Li, Xiao; Gao, Xiaoxia; Tian, Junsheng; Qin, Xuemei; Du, Guanhua

    2016-01-01

    Seven phthalides, including a new dimeric one named tokinolide C (7), were isolated from Angelicae Sinensis Radix and characterized. The structures of these compounds were elucidated on the basis of comprehensive analysis of spectroscopic data and comparison with literature data. All of the compounds were evaluated for their cytotoxic activities against the A549, HCT-8, and HepG2 cancer cell lines. Riligustilide (4) showed cytotoxicity against three cancer cell lines, with IC50 values of 13.82, 6.79, and 7.92 μM, respectively. Tokinolide A (6) and tokinolide C (6) exerted low cytotoxicity in these cancer cell lines, while the remaining compounds were inactive. Flow cytometry analysis was employed to evaluate the possible mechanism of cytotoxic action of riligustilide (4). We observed that compound 4 was able to arrest the cell cycle in the G1, S phases and induce apoptosis in a time-dependent manner in HCT-8 cell lines. In addition, these compounds were evaluated for neuroprotective effect against SH-SY5Y cells injured by glutamate. The result showed that ligustilide (1), Z-butylidenephthalide (3) and tokinolide A (6) exhibited significant neuroprotective effects. PMID:27128890

  16. Neuroprotective Effect of Radix Trichosanthis Saponins on Subarachnoid Hemorrhage

    PubMed Central

    Chen, Ying; Sun, Haiyan; Huang, Liyong; Li, Juxiang; Zhou, Wenke; Chang, Jingling

    2015-01-01

    Redox homeostasis has been implicated in subarachnoid hemorrhage (SAH). As a result, antioxidants and/or free radical scavengers have become an important therapeutic modality. Considering that radix trichosanthis (RT) saponins exhibited strong antioxidant ability both in vivo and in vitro, the present study aimed to reveal whether the neuroprotective activities of RT saponins were mediated by p38/p53 signal pathway after SAH. An established SAH model was used and superoxide dismutase (SOD), malondialdehyde (MDA), induced nitric oxide synthase (iNOS), nitric oxide (NO), lactate dehydrogenase (LDH), p-p38, and p53 activation were detected after 48 h of SAH. The results showed that RT saponins inhibited iNOS expression to restore NO to basal level. Moreover, compared with Cu/Zn-SOD, RT saponins (2 mg/kg/d dosage) significantly increased Mn-SOD activity after SAH. Accompanied with lowered NO and elevated SOD, decreased p38 phosphorylation and p53 activities were observed, especially for RT saponins at 2 mg/kg/d dosage. In this setting, the neurological outcome was also improved with less neuronal cells damage after RT saponins pretreatment. Our findings demonstrated the beneficial effects of RT saponins in enhancing neuroprotective effects by deducing iNOS activity, normalizing SOD level, and inhibiting p-p38 and p53 expression, hence offering significant therapeutic implications for SAH. PMID:26089937

  17. Radiological properties of normoxic polymer gel dosimeters

    SciTech Connect

    Venning, A.J.; Nitschke, K.N.; Keall, P.J.; Baldock, C.

    2005-04-01

    The radiological properties of the normoxic polymer gel dosimeters MAGIC, MAGAS, and MAGAT [methacrylic and ascorbic acid in gelatin initiated by copper; methacrylic acid gelatine gel with ascorbic acid; and methacrylic acid gelatine and tetrakis (hydroxymethyl) phosphonium chloride, respectively] have been investigated. The radiological water equivalence was determined by comparing the polymer gel macroscopic photon and electron interaction cross sections over the energy range from 10 keV to 20 MeV and by Monte Carlo modeling of depth doses. Normoxic polymer gel dosimeters have a high gelatine and monomer concentration and therefore mass density (kg m{sup -3}) up to 3.8% higher than water. This results in differences between the cross-section ratios of the normoxic polymer gels and water of up to 3% for the attenuation, energy absorption, and collision stopping power coefficient ratios through the Compton dominant energy range. The mass cross-section ratios were within 2% of water except for the mass attenuation and energy absorption coefficients ratios, which showed differences with water of up to 6% for energies less than 100 keV. Monte Carlo modeling was undertaken for the polymer gel dosimeters to model the electron and photon transport resulting from a 6 MV photon beam. The absolute percentage differences between gel and water were within 1% and the relative percentage differences were within 3.5%. The results show that the MAGAT gel formulation is the most radiological water equivalent of the normoxic polymer gel dosimeters investigated due to its lower mass density measurement compared with MAGAS and MAGIC gels.

  18. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2008-10-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:18958416

  19. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2009-05-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:19471880

  20. Performance evaluation of a colorimetric hydrazine dosimeter

    NASA Astrophysics Data System (ADS)

    Brenner, Karen P.; Rose-Pehrsson, Susan L.

    1994-06-01

    A dosimeter for real-time, colorimetric detection of hydrazine in air has been developed. The passive badge consists of a dosimeter card containing a vanillin solution coated on a thin paper substrate. The active patch consists of a thick cellulose substrate coated with a vanillin solution. When placed in a plastic sample holder attached to a personnel pump, up to 5 L/min can be drawn through the active badge substrate. Through a condensation reaction, vanillin reacts with hydrazine to form a colored product that absorbs in the visible region. The hydrazone formed in the reaction is yellow; its intensity is proportional to the dose. When exposed passively to hydrazine, the experimental detection limit is less than 20 ppb-hrs. Extrapolated results indicate a detection limit of less than 5 ppb-hrs for long sampling periods. Actively sampling of hydrazine vapors gives an experimental detection limit of less than 100 ppb-L at a sample rate of 5 L/min. Relative humidity effects on badge response were minor. High humidity enhanced the color development on the vanillin badge; while low humidity had no effect on badge response. Interference testing of the dosimeters revealed a tobacco smoke interference. Preliminary shelf life tests indicated no decrease in sensitivity to hydrazine when stored at room temperature for 6 months.

  1. Use of two dosimeters for better estimation of effective dose

    NASA Astrophysics Data System (ADS)

    Kim, Chan-Hyeong

    Obviously, a single dosimeter on the chest can underestimate effective dose (E) and effective dose equivalent (HE) significantly when radiation comes from the back because the dosimeter on the chest is shielded by the body of a radiation worker. This problem can be solved by using an extra dosimeter on the back so that at least one dosimeter is always directly exposed to radiation. In this work, the use of two dosimeters was studied using the MCNP code and mathematical phantoms. First, an optimal combination of dosimeter weighting factors was found to be 0.58 and 0.42 for chest and back dosimeters, respectively, through a systematic optimization process. The optimal algorithm, which uses these weighting factors, was superior to other algorithms reported in the literature. The underestimation problem when using a single-dosimeter approach for posterior incident radiation was completely solved by using two dosimeters and the optimal algorithm. The two-dosimeter approach also estimated E and HE very well for a broad range of frontal incident photon beams, neither underestimating E or HE by more than 11%, nor overestimating by more than about 50%. Although the use of two dosimeters effectively solved the underestimation problem of the single-dosimeter approach for posterior incident radiation, this approach overestimated E and HE for lateral, overhead, and underfoot beam directions. However, this overestimation can be reduced by using suitably selected anisotropic-responding dosimeters. To study the effect of anisotropic-responding properties of personal dosimeters on the estimation of E and HE, this work considered several types of anisotropic-responding dosimeters. In practical exposure situations, radiation workers move during exposure, which results in less overestimation of E and HE than static lateral, overhead, and underfoot exposures. To quantify the reduction of the overestimation by the movement of radiation workers, we averaged photon beam results over

  2. Role of gel dosimeters in boron neutron capture therapy.

    PubMed

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

    2015-09-01

    Gel dosimeters have acquired a unique status in radiotherapy, especially with the advent of the new techniques in which there is a need for three-dimensional dose measurement with high spatial resolution. One of the techniques in which the use of gel dosimeters has drawn the attention of the researchers is the boron neutron capture therapy. Exploring the history of gel dosimeters, this paper sets out to study their role in the boron neutron capture therapy dosimetric process. PMID:26070173

  3. Hanford beta-gamma personnel dosimeter prototypes and evaluation

    SciTech Connect

    Fix, J.J.; Holbrook, K.L.; Soldat, K.L.

    1983-04-01

    Upgraded and modified Hanford dosimeter prototypes were evaluated for possible use at Hanford as a primary beta-gamma dosimeter. All prototypes were compatible with the current dosimeter card and holder design, as well as processing with the automated Hanford readers. Shallow- and deep-dose response was determined for selected prototypes using several beta sources, K-fluorescent x rays and filtered x-ray techniques. All prototypes included a neutron sensitive chip. A progressive evaluation of the performance of each of the upgrades to the current dosimeter is described. In general, the performance of the current dosimeter can be upgraded using individual chip sensitivity factors to improve precision and an improved algorithm to minimize bias. The performance of this dosimeter would be adequate to pass all categories of the ANSI N13.11 performance criteria for dosimeter procesors, provided calibration techniques compatible with irradiations adopted in the standard were conducted. The existing neutron capability of the dosimeter could be retained. Better dosimeter performance to beta-gamma radiation can be achieved by modifying the Hanford dosimeter so that four of the five chip positions are devoted to calculating these doses instead of the currently used two chip positions. A neutron sensitive chip was used in the 5th chip position, but all modified dosimeter prototypes would be incapable of discriminating between thermal and epithermal neutrons. An improved low energy beta response can be achieved for the current dosimeter and all prototypes considered by eliminating the security credential. Further improvement can be obtained by incorporating the 15-mil thick TLD-700 chips.

  4. Comparison of the fiber optic dosimeter and semiconductor dosimeter for use in diagnostic radiology

    NASA Astrophysics Data System (ADS)

    Yoo, W. J.; Shin, S. H.; Sim, H. I.; Hong, S.; Kim, S. G.; Jang, J. S.; Kim, J. S.; Jeon, H. S.; Kwon, G. W.; Jang, K. W.; Cho, S.; Lee, B.

    2014-05-01

    A fiber-optic dosimeter (FOD) was fabricated using a plstic scintillating fiber, a plastic optical fiber, and a multi-pixel photon counter to measure entrance surface dose (ESD) in diagnostic radiology. Under changing tube current and irradition time of the digital radiography (DR) system, we measured the scintillating light and the ESD simultaneously. As experiemtnal results, the total counts of the FOD were changed in a manner similar to the ESDs of the semiconductor dosimeter (SCD). In conclusion, we demonstrated that the proposed FOD minimally affected the diagnostic information of DR image while the SCD caused serious image artifacts.

  5. GAMMA AND X-RAY DOSIMETER AND DOSIMETRIC METHOD

    DOEpatents

    Taplin, G.V.; Douglas, C.H.; Sigoloff, S.C.

    1958-08-19

    An improvement in colorimetric gamma and x-ray dosimeter systems and a self-contained. hand carried dostmeter of the afore-mentioned type ts described. A novel point of the invention ltes in the addition of specific quantities of certain normalizing agents to the two phase chlorinated hydro-carbon-aqueous dyc colortmetric dosimeter to eliminate the after reaction and thereby extend the utility of such systein. The structure of the two phase colorimetric dosimeter tubes and the carrying case for the tubes of the portable dosimeter are unique features.

  6. Use of Xylitol To Enhance the Therapeutic Efficacy of Polymethylmethacrylate-Based Antibiotic Therapy in Treatment of Chronic Osteomyelitis

    PubMed Central

    Beenken, Karen E.; Bradney, Laura; Bellamy, William; Skinner, Robert A.; McLaren, Sandra G.; Gruenwald, M. Johannes; Spencer, Horace J.; Smith, James K.; Haggard, Warren O.

    2012-01-01

    Using a rabbit model of postsurgical osteomyelitis, we demonstrate that incorporation of xylitol into polymethylmethacrylate (PMMA) bone cement enhances the elution of daptomycin under in vivo conditions. We also demonstrate that this can be correlated with an improved therapeutic outcome in the treatment of a chronic bone infection following surgical debridement. PMID:22948866

  7. Comparison of the Protective Effects of Radix Astragali, α-Lipoic Acid, and Vitamin E on Acute Acoustic Trauma

    PubMed Central

    Xiong, Min; Lai, Huangwen; Yang, Chuanhong; Huang, Weiyi; Wang, Jian; Fu, Xiaoyan; He, Qinglian

    2012-01-01

    Objective Oxidative damage is a critical role which involves hearing loss induced by impulse noise. That exogenous antioxidant agents reduce noise induced hearing loss (NIHL) has been well demonstrated in both animal studies and clinical practices. Choosing a stronger and more effective antioxidant is very important for treatment of NIHL. Vitamin E, α-lipoic acid, and radix astragali are the most commonly used anti-oxidants for cochlear oxidative damage from acoustic trauma. In this study, the protective effects of radix astragali, α-lipoic acid, and vitamin E on acute acoustic trauma are investigated. Methods Guinea pigs in the experimental groups were intragastrically administered vitamin E, α-lipoic acid, and radix astragali. Auditory thresholds were assessed by sound-evoked auditory brainstem response (ABR) at click and tone bursts of 8, 16 and 32 kHz, 24 hours before and 72 hours after exposure to impulse noise. Cochlear malondialdehyde (MDA) concentrations were detected. Hair cell damage was analyzed by scanning electron microscopy. Results Vitamin E, α-lipoic acid, and radix astragali significantly reduced ABR deficits, reduced hair cell damage, and decreased the concentrations of MDA. α-lipoic acid and radix astragali were better than vitamin E, and there were no significant differences between α-lipoic acid and radix astragali. Conclusions α-lipoic acid or radix astragali are recommended for treatment of NIHL. PMID:24179406

  8. [Bioassay for enrich-blood bioactivity of Agelicae Sinensis Radix].

    PubMed

    Wang, Xiao-xiao; Zhang, Li-hong; Li, Xi; Wang, Ye; Rong, Zu-yuan; Wei, Hong-ping; Song, Qi-rui; Lv, Guang-hua

    2015-04-01

    Danggui, Agelicae Sinensis Radix, is a widely used Chinese herb to enrich blood, but its quality cannot be effectively assessed by the known chemical markers such as ferulic acid, ligustilide, polysaccharides, etc. A new bioassay was therefore developed to quantify the Enrich-Blood Bioactivity (EBB) for the quality assessment of Danggui raw materials. Danggui sample was first extracted with ethanol and water, respectively. Then the ethanolic extract and water extract were mixed as a test sample to quantify the amount of EBB by mice experiment. The blood deficiency mode in mice was developed by intraperitoneal injecting cyclophospharmide and phenylhdrazine hydrochloride. The quantity of red blood cell was chosen as EBB marker. Cyclosporine A was chosen as a control substance. EBB in analytes was quantified by the amount reaction of parallel line analysis (3, 3') method. The results indicated that the reliability test for quantifying EBB was passed through and the measured value was valid. The analytes showed the significant EBB (P < 0.05). The correlation coefficient was 0.9984 (n=5) between the amount of cyclosporine A (0.035-0.56 g x kg(-1)) and the increased number of red blood cell. The relative standard deviation (RSY) on the amount of EBB was estimated to be 6.15% (n = 6) by six replicated tests, and the confidence limit rate was 26.68% (n = 6). Five Danggui samples, which were collected from different cultivation areas with various morphological characters, showed the variety of EBB in the range of 21.95-44.16 U x g(-1). It is concluded that the developed method is accurate to quantify the EBB of Danggui raw materials, and is therefore suitable to assess its quality. PMID:26281565

  9. The WS2 quantum dot: preparation, characterization and its optical limiting effect in polymethylmethacrylate.

    PubMed

    Long, Hui; Tao, Lili; Chiu, Chun Pang; Tang, Chun Yin; Fung, Kin Hung; Chai, Yang; Tsang, Yuen Hong

    2016-10-14

    Due to the matching surface energy, WS2 quantum dots (QDs) can be obtained through direct liquid exfoliation in N-methyl-2-pyrrolidone rather than an ethanol and water mixture. Ultra-small WS2 QDs with a diameter of 2.4 nm are fabricated by an ultrasound method followed by high speed centrifugation up to 10 000 rpm. An excellent nonlinear optical (NLO) property of the WS2 QD/ polymethylmethacrylate (PMMA) composite for the nanosecond pulsed laser at both 532 and 1064 nm has been measured. Results illustrate the lower onset thresholds (F ON ), lower optical limiting thresholds (F OL ), and higher two-photon absorption coefficient (β) with respect to a higher concentration of embedded WS2 QDs into the PMMA solid state matrix for both 532 and 1064 nm. PMID:27607761

  10. Manufacturing of embedded multimode waveguides by reactive lamination of cyclic olefin polymer and polymethylmethacrylate

    NASA Astrophysics Data System (ADS)

    Kelb, Christian; Rother, Raimund; Schuler, Anne-Katrin; Hinkelmann, Moritz; Rahlves, Maik; Prucker, Oswald; Müller, Claas; Rühe, Jürgen; Reithmeier, Eduard; Roth, Bernhard

    2016-03-01

    We demonstrate the manufacturing of embedded multimode optical waveguides through linking of polymethylmethacrylate (PMMA) foils and cyclic olefin polymer (COP) filaments based on a lamination process. Since the two polymeric materials cannot be fused together through interdiffusion of polymer chains, we utilize a reactive lamination agent based on PMMA copolymers containing photoreactive 2-acryloyloxyanthraquinone units, which allows the creation of monolithic PMMA-COP substrates through C-H insertion reactions across the interface between the two materials. We elucidate the lamination process and evaluate the chemical link between filament and foils by carrying out extraction tests with a custom-built tensile testing machine. We also show attenuation measurements of the manufactured waveguides for different manufacturing parameters. The lamination process is in particular suited for large-scale and low-cost fabrication of board-level devices with optical waveguides or other micro-optical structures, e.g., optofluidic devices.

  11. Tissue biocompatibility of kevlar aramid fibers and polymethylmethacrylate, composites in rabbits.

    PubMed

    Henderson, J D; Mullarky, R H; Ryan, D E

    1987-01-01

    Two groups of female NZW rabbits were implanted in the paravertebral muscles with aramid (du Pont Kevlar aramid 49) fibers and aramid-polymethylmethacrylate (PMMA) composites for 14 and 28 days. Rabbits were killed at these times periods, necropsies performed, sites scored for gross tissue response, and tissue specimens containing the implants removed for histopathological evaluation. A mild fibrous tissue reaction was observed around all implants containing aramid fiber similar to that observed around the silicone control implant. Some foreign body giant cells were also present adjacent to the fibers. An intense necrotic inflammatory reaction was present around the positive control material (PVC Y-78). The tissue response to implantation of aramid fiber and fiber-PMMA composites indicates that aramid is a biocompatible material. PMID:3558440

  12. Photoreactive phase conjugation strength in disperse red 1 doped poly(methylmethacrylate) thin films

    NASA Astrophysics Data System (ADS)

    Liu, Sean; Wang, Wei Lin; Fang, Chien Cheng; Huang, Tzer-Hsiang; Hsu, Chia Chen

    2005-01-01

    Near-resonant optical pumping was used to modulate third-order susceptibility χ(3) in disperse red 1 doped poly(methylmethacrylate) thin films. An optically pumped degenerate four-wave mixing (DFWM) experiment was conducted to examine the photoreactive phase conjugation (PC) signals. Experimental results indicated a large anisotropy in PC signals arising from ∣χ3333(3)∣2, and almost isotropic PC signals from ∣χ1331(3)∣2 under s-polarized and p-polarized pump fields. Additionally, a dynamic microscopic model, based on the theory developed by Sekkat et al.[Synth. Met. 54, 373 (1993); J. Phys. Chem. B 106, 12407 (2002); Opt. Commun. 229, 291 (2004)] was presented to describe the observed optical nonlinear responses. Results from the model were generally consistent with those of the optically pumped DFWM experiment.

  13. Reconstruction of bony facial contour deficiencies with polymethylmethacrylate implants: case report

    PubMed Central

    ABDO FILHO, Ruy C. C.; OLIVEIRA, Thais M.; LOURENÇO, Natalino; GURGEL, Carla; ABDO, Ruy C.C.

    2011-01-01

    Facial trauma can be considered one of the most serious aggressions found in the medical centers due to the emotional consequences and the possibility of deformity. In craniofacial surgery, the use of autologous bone is still the first choice for reconstructing bony defects or irregularities. When there is a shortage of donor bone or a patient refuses an intracranial operation, alloplastic materials such as polymethylmethacrylate (PMMA) can be used. The PMMA prosthesis can be pre-fabricated, bringing advantages such as reduction of surgical time, easy technical handling and good esthetic results. This paper describes the procedures for rehabilitating a patient with PMMA implants in the region of the face, recovering the facial contours and esthetics of the patient. PMID:21952926

  14. Interaction of low-energy ions (< 10 eV) with polymethylmethacrylate during plasma treatment

    NASA Astrophysics Data System (ADS)

    Gröning, P.; Küttel, O. M.; Collaud-Coen, M.; Dietler, G.; Schlapbach, L.

    1995-05-01

    Using in-situ X-ray photoelectron spectroscopy (XPS) we investigated the chemical modification of the polymethyl-methacrylate (PMMA) surfaces after plasma and low-energy ion beam treatment. A comparison between plasma and ion beam treatment has shown, that for noble gases both treatments produce absolutely the same modifications of the chemical composition on the PMMA surface. In reactive gases (O 2, N 2) molecular ions were found to decompose polar bonds at the polymer surface, but they do not contribute to the incorporation of reactive gas atoms. Reactive atomic ions and radicals are responsible for this incorporation. We found that in the case of PMMA less than three ions are needed to decompose the ester group (OCO) completely. Therefore, we conclude that the decomposition of the ester group by ions is a chemical and not a physical effect due to the kinetic energy of the ions.

  15. Surface energy changes produced by ultraviolet-ozone irradiation of poly(methylmethacrylate), polycarbone and polytetrafluoroethylene

    NASA Technical Reports Server (NTRS)

    Ponter, A. B.; Jones, W. R., Jr.; Jansen, R. H.

    1994-01-01

    Contact angles of water and methylene iodide were measured as a function of UV/O3 treatment time for three polymers: poly(methylmethacrylate) (PMMA), polycarbonate, and polytetrafluoroethylene (PTFE). Surface roughnesses were also measured. Surface free energies were then calculated using relationships developed by Kaelble and Neumann. The surface energy of polycarbonate was found to increase (60 percent) during UV/O3 treatment. However, calculations on PMMA were hampered by the formation of a water soluble surface product. On PTFE surfaces, the UV/O3 treatment etched the surface causing large increases in surface roughness, rendering contact angle measurements impossible. It is concluded that care must be taken in interpreting contact angle measurements and surface energy calculations on UV/O3 treated polymer surfaces.

  16. A study of laser-based removal of polymethylmethacrylate bone cement.

    PubMed

    O'Neill, W; Kapadia, P; Thomas, T

    1996-06-01

    Complications are often produced with the removal of bone cement from the femoral cavity in the treatment of a failed hip prosthesis. Apart from being slow and difficult the conventional process runs the risk of producing damage to the femur. Ultrasonic techniques have been suggested to achieve these ends but removal of the cement by this approach is not entirely easy. The alternative laser-based approach would seem to have significant advantages over conventional techniques. The laser is capable of delivering energy to a specific region or surface under close control. The choice of laser is determined by its ability to ablate the cement and the ease with which it can be delivered to the base of the femur cavity. This paper examines several laser wavelengths: CO2 (10.6 microns), excimer (248 nm), Hol:YAG (2.12 microns), and presents polymethylmethacrylate (PMMA) vaporization thresholds for each laser. PMID:10163354

  17. Carboplatin loaded polymethylmethacrylate nano-particles in an adjunctive role in retinoblastoma: An animal trial

    PubMed Central

    Shome, Debraj; Kalita, Dhrubajyoti; Jain, Viral; Sarin, Rajiv; Maru, Girish B.; Bellare, Jayesh R.

    2014-01-01

    Purpose: The purpose of the study is to compare the intra-vitreal concentrations of carboplatin, post peri-ocular injections of commercially available carboplatin (CAC) and a novel carboplatin loaded polymethylmethacrylate nanoparticulate carboplatin (NPC), in either eye, as a model system for treatment of advanced intra-ocular retinoblastoma (RB). Design: Experimental, comparative, animal study. Materials and Methods: Polymethylmethacrylate nanoparticles were prepared by free radical emulsion polymerization of methyl methacrylate in aqueous solution of carboplatin in the presence of surfactant sodium dodecyl sulfate and thermal initiator ammonium persulfate. 21 Sprague-Dawley rats, aged between 6 weeks and 3 months were enrolled. The right eye of each rat was injected peri-ocularly with CAC formulation (1 ml of 10 mg/ml) and the left eye with NPC (1 ml of 10 mg/ml), post-anesthesia, by an ophthalmologist trained in ocular oncology. Three rats each were euthanized on days 1, 3, 5, 7, 14, 28 and 42, post-injection and both eyes were carefully enucleated. Intra-vitreal concentrations of CAC and NPC were determined with Inductively Coupled Plasma Atomic Emission Spectroscopy. Analysis of data was done with paired t-test. Results: The intra-vitreal concentration of carboplatin with NPC was ~3-4 times higher than with CAC in all animals, on all the days (P < 0.05). Conclusion: A higher trans-scleral permeability gradient is obtained with the novel nanoparticles than with the commercial drug, leading to sustained higher levels of carboplatin in the vitreous. Peri-ocular injection of NPC could thus have an adjuvant efficacy in the treatment for advanced clinical RB, specifically those with vitreous seeds. PMID:24881606

  18. Evaluation of discrepancies between thermoluminescent dosimeter and direct-reading dosimeter results

    SciTech Connect

    Shaw, K.R.

    1993-07-01

    Currently at Oak Ridge National Laboratory (ORNL), the responses of thermoluminescent dosimeters (TLDs) and direct-reading dosimeters (DRDs) are not officially compared or the discrepancies investigated. However, both may soon be required due to the new US Department of Energy (DOE) Radiological Control Manual. In the past, unofficial comparisons of the two dosimeters have led to discrepancies of up to 200%. This work was conducted to determine the reasons behind such discrepancies. For tests conducted with the TLDs, the reported dose was most often lower than the delivered dose, while DRDs most often responded higher than the delivered dose. Trends were identified in personnel DRD readings, and ft was concluded that more training and more control of the DRDs could improve their response. TLD responses have already begun to be improved; a new background subtraction method was implemented in April 1993, and a new dose algorithm is being considered. It was concluded that the DOE Radiological Control Manual requirements are reasonable for identifying discrepancies between dosimeter types, and more stringent administrative limits might even be considered.

  19. Radix grafts in cosmetic rhinoplasty: lessons from an 8-year review.

    PubMed

    Cohen, Justin C; Pearlman, Steven J

    2012-11-01

    We describe our experience with radix augmentation during cosmetic rhinoplasty over an 8-year period using both autologous and synthetic grafts and provide insight into maximizing success. We discuss various surgical considerations, including patient selection, graft materials, and dealing with complications. We focus on our operative technique and provide patient examples. PMID:22869164

  20. [Determination the chemical speciation of Cu, Zn, Fe and Mn in Radix Scutellariae by AAS].

    PubMed

    Miao, Shan; Sun, Ji-yuan; Xie, Yan-hua; Wang, Jian-bo; Shi, Xiao-peng; Ding, Yuan-yuan; Bi, Lin-lin; Gao, Shuang-bin; Wang, Si-wang

    2009-05-01

    An analysis method was developed to determine the chemical speciation of Cu, Zn, Fe and Mn in radix scutellariae decoction using atomic absorption spectroscopy(AAS). The decoction can be divided into suspension and soluble species by 0.45 microm filter membrane and the soluble species can be separated into organism and inorganic species by LSA-10 macroporous resin. These elements in water-soluble test samples can be divided into alcohol-soluble and water-soluble by adopting n-octyl alcohol-water allocation system in man-made gastric acidity. Then, the concentration of these elements was determined by AAS, which provided more chemical speciation information about these elements instead of the total amount of them only in radix scutellariae. Deteotion limit of Cu, Zn and Mn by using the method was all 0.01 microg x mL(-1) and was 0.02 microg x mL(-1) for Fe. The RSD was in the range of 1.5%-3.6% (n=11) and the recovery rate of soluble species and inorganic species were in range of 96.7%-105.0%. The method has been successfully applied to determine the chemical speciation of Cu, Zn, Fe and Mn in radix scutellariae, which was very important for overall study of radix scutellariae. PMID:19650506

  1. [Comparison and correlative analysis of trace elements in five kinds of radix curcumae].

    PubMed

    Tian, Yu-mei; Zhou, Dan; Zhang, Wei; Cheng, Cun-gui

    2008-09-01

    Traditional Chinese medicine materials (TCM) contained abundant trace elements needed in human body. Mixed acid (HNO3:HClO4) was added into samples treated by microwave digestion, and a systematic study was carried out by selection of the most appropriate working conditions and optimization of the sample mass. Some inorganic elements in 5 kinds of radix curcumae (Curcuma wenyujin Y. H. Chen et C. Ling, Curcuma longa L., Curcuma kwangsiensis S. G. Lee et C. F. Liang, Curcuma phaeocaulis Val. and Curcuma chuanyujin C. K Hsieh et H. Zhang) necessary to lives were determined by flames atomic absorption spectrometry (AAS). Elements, such as K, Ca, Na, Mg, Zn, Fe, Cu and Mn were detected. The results show that there are similar elements in the five kinds of radix curcumae, while differences only exist in a few elements contents. The correlative analysis of trace elements in samples was carried out by cluster analysis of the 4 kinds of radix curcumae (Curcuma wenyujin Y. H. Chen et C. Ling, Curcuma longa L., Curcuma kwangsiensis S. G. Lee et C. F. Liang and Curcuma phaeocaulis Val. ) in codex populations in a cluster, different from the unofficial sample (Curcuma chuanyujin C. K. Hsieh et H. Zhang). The cluster analysis results are consistent with the morphological characteristics of the traditional taxonomy results. The results showed that the analytic method is advisable. This paper provides scientific basis for deeply studing the relation between trace elements and drug effect of radix curcumae. PMID:19093592

  2. Real-time optical fiber dosimeter probe

    NASA Astrophysics Data System (ADS)

    Croteau, André; Caron, Serge; Rink, Alexandra; Jaffray, David; Mermut, Ozzy

    2011-03-01

    There is a pressing need for a passive optical fiber dosimeter probe for use in real-time monitoring of radiation dose delivered to clinical radiation therapy patients. An optical fiber probe using radiochromic material has been designed and fabricated based on a thin film of the radiochromic material on a dielectric mirror. Measurements of the net optical density vs. time before, during, and after irradiation at a rate of 500cGy/minute to a total dose of 5 Gy were performed. Net optical densities increased from 0.2 to 2.0 for radiochromic thin film thicknesses of 2 to 20 μm, respectively.

  3. Evaluation of a Colorimetric Personal Dosimeter for Nitrogen Oxide.

    ERIC Educational Resources Information Center

    Diamond, Philip

    A personal colorimetric dosimeter for nitrogen dioxide was developed. Tests were performed to determine the response of these strips to various concentrations of NO2. The dosimeter strips were satisfactory for approximate determinations of total exposure (concentration + time) of nitrogen dioxide. The total exposure was calculated in terms of time…

  4. A remote fiber optic dosimeter network for detecting hydrazine vapor

    SciTech Connect

    Klimcak, C.; Radhakrishnan, G.; Jaduszliwer, B.

    1995-12-31

    A fiber optic chemical dosimeter has been developed for use in the remote detection of vapors of toxic amine rocket fuels (hydrazine and its substituted derivatives) that are used as Air Force and civilian launch sites. The dosimeter employs a colorimetric indicating reagent immobilized in a porous sol-gel cladding on multimode fiber. This reagent reacts selectively with the fuel vapor to produce a strongly absorbing cladding that introduces light propagation losses in the fiber; these losses indicate the presence of hydrazine (N{sub 2}H{sub 4}) vapor. The absorption occurs over a broad spectral range ideally suited for interrogation by semiconductor diode lasers. The authors have shown that the dosimeter yields an average hydrazine detectivity of 2.3 exposures of the dosimeter to laboratory air have not adversely affected the dosimeter. Additionally, its response to ammonia vapor has been determined to be 9,200 times smaller than its response to hydrazine vapor.

  5. Numerical simulation of `DMSP` dosimeter response

    SciTech Connect

    Jordan, T.M. ||

    1993-12-31

    Four Defense Meteorological Satellite Program (DMSP) dosimeters were modeled for numerical simulation of radiation response. The modeling included the hemispherical aluminum dome, the solid state detector, and the tungsten base plate. Orbits were generated for 840 km and 98 degrees inclination and used with 1965 and 1985 magnetic field models and the AP8 and AE8 data sets to obtain solar minimum and solar maximum integral fluences for protons and electrons. Adjoint Monte Carlo methods were then used to simulate the transport of these environments in the geometric models of the dosimeters. Volume average dose calculations were used to calculate the response of the LOLET (less than 1 MeV deposited per particle) channels to electrons and secondary bremsstrahlung. Monte Carlo methods were used, in conjunction with a pulse height analysis, to obtain the proton response of the LOLET and HILET (1 to 10 MeV deposited per particle) channels. The HILET and LOLET responses obtained from these calculations are in good agreement with DMSP measurements for 1984-85.

  6. A scintillating fiber dosimeter for radiotherapy

    NASA Astrophysics Data System (ADS)

    Bartesaghi, G.; Conti, V.; Bolognini, D.; Grigioni, S.; Mascagna, V.; Prest, M.; Scazzi, S.; Mozzanica, A.; Cappelletti, P.; Frigerio, M.; Gelosa, S.; Monti, A.; Ostinelli, A.; Giannini, G.; Vallazza, E.

    2007-10-01

    Radiotherapy, together with chemotherapy and surgery, is one of the main methods applied in the fight against cancer; in order to increase the chances of a successful radiotherapy treatment the dose delivery to the tumor and the surrounding normal tissues has to be computed with high accuracy. Traditional dosimeters are accurate but single channel (ionization chambers and diodes) or non real-time (radiographic films) devices. At present there is no device water equivalent that can perform real-time and bidimensional measurements of a dose distribution. This article describes the development of a real-time dosimeter based on scintillating fibers for photon and electron beams; the fibers are made of polystyrene, that is water equivalent and thus tissue equivalent, allowing a direct dose calculation. Three prototypes (single and multichannel) have been assembled, consisting in small scintillators coupled to white fibers that carry the light to photomultiplier tubes. In this article the prototypes and the readout electronics are described, together with the results of the measurements with electron and photon beams with energy up to 20 MeV (produced by linear accelerators Varian Clinac 1800 and 2100CD).

  7. Bioactive polymethylmethacrylate bone cement modified with combinations of phosphate group-containing monomers and calcium acetate.

    PubMed

    Liu, Jinkun; Shirosaki, Yuki; Miyazaki, Toshiki

    2015-04-01

    Bone cement from polymethylmethacrylate powder and methylmethacrylate liquid has been successfully demonstrated as artificial material to anchor joint replacements in bone. However, it lacks the capability to bond directly to bone, so long-term implantation leads to an increased risk of loosening. Bioactive materials show better performance in fixation to bone, and the chemical bonding depends on bone-like apatite formation. This is triggered by surface reactions with body fluid. For these reactions, superficial functional groups like silanol (Si-OH) are ideal sites to induce apatite nucleation and the release of Ca(2+) ions accelerates the apatite growth. Therefore, incorporation of materials containing these key components may provide the cement with apatite-forming ability. In this study, phosphoric acid 2-hydroxyethyl methacrylate ester or bis[2-(methacryloyloxy)ethyl] phosphate supplying a phosphate group (PO4H2) was added into methylmethacrylate liquid, while calcium acetate as a source of Ca(2+) ions was mixed into polymethylmethacrylate powder. The influences of the combinations on the setting time and compressive strength were also investigated. Apatite was formed on the cements modified with 30 mass% of phosphoric acid 2-hydroxyethyl methacrylate ester or bis[2-(methacryloyloxy)ethyl] phosphate. The induction period was shortened with increased amounts of Ca(CH3COO)2. The setting time could be controlled by the Ca(CH3COO)2/monomer mass ratio. Faster setting was achieved at a ratio close to the mixing ratio of the powder/liquid (2:1), and both increases and decreases in the amount of Ca(CH3COO)2 prolonged the setting time based on this ratio. The highest compressive strength was 88.8 ± 2.6 MPa, higher than the lowest limit of ISO 5833 but was lower than that of the simulated body fluid-soaked reference. The increase of additives caused the decline in compressive strength. In view of balancing apatite formation and clinical standard, bis[2

  8. SU-E-T-265: Presage Thin Sheet Dosimeter Characterization

    SciTech Connect

    Dumas, M; Rakowski, J

    2014-06-01

    Purpose: To quantify the sensitivity and stability of the Presage dosimeter in sheet form for different concentrations of chemicals and for a diverse range of clinical photon energies. Methods: Presage polymer dosimeters are formulated to investigate and optimize their sensitivity and stability. The dosimeter is composed of clear polyurethane base, leucomalachite green reporting dye, and bromoform radical initiator in 1mm thick sheets. The chemicals are well mixed together, cast in an aluminum mold, and left to cure at 60 psi for a minimum of 2 days. Dosimeter response will be characterized at multiple energies including Co-60, 6 MV, 15 MV, 50 kVp, and 250 kVp. The dosimeters are read by an Epson 10000 XL scanner at 800 dpi, 2{sup 16} bit depth. Red component images are analyzed with ImageJ. Results: Analysis of optical density verse dose for Co-60 energies indicates that the bromoform containing Presage was able to quantify dose from 0 to 300 Gy, with saturation beyond 300 Gy. Initial results show two regions of linear response, 0–100 Gy and 150–300 Gy. The 150–300 Gy region has a sensitivity of 0.0024 net OD/Gy. Further results on other energies are still in progress. Conclusions: This work shows the potential for use of thin sheets of Presage dosimeter as a dosimeter capable of being analyzed with a flatbed scanner.

  9. Limitations of using dosimeters in impulse noise environments.

    PubMed

    Kardous, Chucri A; Willson, Robert D

    2004-07-01

    The National Institute for Occupational Safety and Health (NIOSH) investigated the capabilities of noise dosimeters to measure personal exposure to impulse noise. The two leading types of commercially available dosimeters were evaluated in terms of their ability to measure and integrate impulses generated from gunfire during live-fire exercises at a law enforcement indoor firing range. Sound measurements were conducted throughout the firing range using dosimeters, sound level meters, and a measurement configuration that consisted of a quarter-inch microphone and a digital audiotape recorder to capture the impulse waveforms. Personal dosimetry was conducted on eight shooters, an observer, and the range master. Peak levels from gunfire reached 163 decibels (dB), exceeding the nominal input limit of the dosimeters. The dosimeters "clipped" the impulses by acting as if the gunfire had a maximum level of 146 dB. In other cases, however, peak levels (e.g., 108 dB) were below the dosimeter input limits, but the dosimeters still showed a peak level of 146 dB. Although NIOSH recommends that sound levels from 80 to 140 dB (A-weighted) be integrated in the calculation of dose and the time-weighted average, our present data suggest this criterion may be inadequate. These results showed that some instruments are incapable of providing accurate measures of impulse sounds because of their electroacoustic limitations. PMID:15238316

  10. Radiation Measured during ISS-Expedition 13 with Different Dosimeters

    NASA Technical Reports Server (NTRS)

    Zhou, D.; Semones, E.; Gaza, R.; Johnson, S.; Zapp, N.; Lee, K.; George, T.

    2008-01-01

    Radiation in low Earth orbit (LEO) is mainly composed of Galactic Cosmic Rays (GCR), solar energetic particles and particles in SAA (South Atlantic Anomaly). The biological impact of space radiation to astronauts depends strongly on the particles linear energy transfer (LET) and is dominated by high LET radiation. It is important to measure the LET spectrum for the space radiation field and to investigate the influence of radiation on astronauts. At present, the preferred active dosimeters sensitive to all LET are the tissue equivalent proportional counter (TEPC) and silicon detectors in various configurations; the preferred passive dosimeters are thermoluminescence dosimeters (TLDs) and optically stimulated luminescence dosimeters (OSLDs) sensitive to low LET as well as CR-39 plastic nuclear track detectors (PNTDs) sensitive to high LET. The TEPC, CR-39 PNTDs, TLDs and OSLDs were used to investigate the radiation exposure for the ISS mission Expedition 13 (ISS-12S) in LEO. LET spectra and radiation quantities (fluence, absorbed dose, dose equivalent and quality factor) were measured for the space mission with different dosimeters. This paper introduces the operational principles for the dosimeters, describes the method to combine the results measured by TLDs/OSLDs and CR-39 PNTDs, and presents the LET spectra and the radiation quantities measured. Keywords: space radiation; cosmic rays; active and passive dosimeters; LET spectra

  11. Calibration system for albedo neutron dosimeters

    SciTech Connect

    Rothermich, N.E.

    1981-01-01

    Albedo neutron dosimeters have proven to be effective as a method of measuring the dose from neutron exposures that other types of neutron detectors cannot measure. Results of research conducted to calibrate an albedo neutron dosemeter are presented. The calibration procedure consisted of exposing the TLD chips to a 46 curie /sup 238/PuBe source at known distances, dose rates and exposure periods. The response of the TLD's is related to the dose rate measured with a dose rate meter to obtain the calibration factor. This calibration factor is then related to the ratio of the counting rates determined by 9-inch and 3-inch Bonner spheres (also called remmeters) and a calibration curve was determined. 17 references, 10 figures, 3 tables.

  12. p-MOSFET total dose dosimeter

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Blaes, Brent R. (Inventor)

    1994-01-01

    A p-MOSFET total dose dosimeter where the gate voltage is proportional to the incident radiation dose. It is configured in an n-WELL of a p-BODY substrate. It is operated in the saturation region which is ensured by connecting the gate to the drain. The n-well is connected to zero bias. Current flow from source to drain, rather than from peripheral leakage, is ensured by configuring the device as an edgeless MOSFET where the source completely surrounds the drain. The drain junction is the only junction not connected to zero bias. The MOSFET is connected as part of the feedback loop of an operational amplifier. The operational amplifier holds the drain current fixed at a level which minimizes temperature dependence and also fixes the drain voltage. The sensitivity to radiation is made maximum by operating the MOSFET in the OFF state during radiation soak.

  13. Characterization of a nuclear accident dosimeter

    SciTech Connect

    Burrows, R.A.

    1995-12-01

    The 23rd nuclear accident dosimetry intercomparison was held during the week of June 12--16, 1995 at Los Alamos National Laboratory. This report presents the results of this event, referred to as NAD 23, as related to the performance of Sandia National Laboratories (SNL) personal nuclear accident dosimeter (PNAD). Two separate critical assemblies, SHEBA and Godiva, were used to generate seven separate neutron spectra for use in dose comparisons. SNL`s PNAD measured absorbed doses that were within +16 to +26% of the reference doses. In addition, a preliminary investigation was undertaken to determine the feasibility of using the data obtained from an irradiated PNAD to correct for body orientation. This portion of the experiment was performed with a TRIGA reactor at the Nuclear Science Center at Texas A and M University.

  14. A miniature MOSFET radiation dosimeter probe.

    PubMed

    Gladstone, D J; Lu, X Q; Humm, J L; Bowman, H F; Chin, L M

    1994-11-01

    Prototype miniature dosimeter probes have been designed, built, and characterized employing a small, radiation sensitive metal oxide semiconductor field effect transistor (MOSFET) chip to measure, in vivo, the total accumulated dose and dose rate as a function of time after internal administration of long range beta particle radiolabeled antibodies and in external high energy photon and electron beams. The MOSFET detector is mounted on a long narrow alumina substrate to facilitate electrical connection. The MOSFET, alumina substrate, and lead wires are inserted into a 16 gauge flexineedle, which, in turn, may be inserted into tissue. The radiation dosimeter probe has overall dimensions of 1.6 mm diam and 3.5 cm length. The MOSFET probe signals are read, stored, and analyzed using an automated data collection and analysis system. Initially, we have characterized the probe's response to long range beta particle emission from 90Y sources in solution and to high energy photon and electron beams from linear accelerators. Since the prototype has a finite substrate thickness, the angular dependence has been studied using beta particle emission from a 90Sr source. Temperature dependence and signal drift have been characterized and may be corrected for. Measurements made in spherical volumes containing 90Y with diameters less than the maximum electron range, to simulate anticipated geometries in animal models, agree well with Berger point kernel and EGS4 Monte Carlo calculations. The results from the prototype probes lead to design requirements for detection of shorter range beta particles used in radioimmunotherapy and lower photon energies used in brachytherapy. PMID:7891632

  15. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, Tuan

    1987-01-01

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique.

  16. Dosimeter for monitoring vapors and aerosols of organic compounds

    DOEpatents

    Vo-Dinh, T.

    1987-07-14

    A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

  17. A new dosimeter formulation for deformable 3D dose verification

    NASA Astrophysics Data System (ADS)

    Høye, E. M.; Skyt, P. S.; Yates, E. S.; Muren, L. P.; Petersen, J. B. B.; Balling, P.

    2015-01-01

    We present the characteristics of a new silicone-based radiochromic dosimeter containing the leuco-malachite green (LMG) dye. The dose response as well as the dose-rate and photon-energy dependence of the dosimeter were characterized. To optimise the dose response, different concentrations of the chemical components were investigated. The dose response was found to decrease exponentially as a function of time after irradiation. A cylindrical dosimeter was produced and irradiated with a volumetric modulated arc therapy plan; the standard deviation between measured and calculated dose was 5% of the total dose.

  18. Personal noise dosimeters: accuracy and reliability in varied settings.

    PubMed

    Cook-Cunningham, Sheri Lynn

    2014-01-01

    This study investigated the accuracy, reliability, and characteristics of three brands of personal noise dosimeters (N = 7 units) in both pink noise (PN) environments and natural environments (NEs) through the acquisition of decibel readings, Leq readings and noise doses. Acquisition periods included repeated PN conditions, choir room rehearsals and participant (N = 3) Leq and noise dosages procured during a day in the life of a music student. Among primary results: (a) All dosimeters exhibited very strong positive correlations for PN measurements across all instruments; (b) all dosimeters were within the recommended American National Standard Institute (ANSI) SI.25-1991 standard of ±2 dB (A) of a reference measurement; and (c) all dosimeters were within the recommended ANSI SI.25-1991 standard of ±2 dB (A) when compared with each other. Results were discussed in terms of using personal noise dosimeters within hearing conservation and research contexts and recommendations for future research. Personal noise dosimeters were studied within the contexts of PN environments and NEs (choral classroom and the day in the life of collegiate music students). This quantitative study was a non-experimental correlation design. Three brands of personal noise dosimeters (Cirrus doseBadge, Quest Edge Eg5 and Etymotic ER200D) were tested in two environments, a PN setting and a natural setting. There were two conditions within each environment. In the PN environment condition one, each dosimeter was tested individually in comparison with two reference measuring devices (Ivie and Easera) while PN was generated by a Whites Instrument PN Tube. In condition two, the PN procedures were replicated for longer periods while all dosimeters measured the sound levels simultaneously. In the NE condition one, all dosimeters were placed side by side on a music stand and recorded sound levels of choir rehearsals over a 7-h rehearsal period. In NE, condition two noise levels were measured during

  19. Beam waist position study for surface modification of polymethyl-methacrylate with femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Caballero-Lucas, F.; Florian, C.; Fernández-Pradas, J. M.; Morenza, J. L.; Serra, P.

    2016-06-01

    Femtosecond lasers are versatile tools to process transparent materials. This optical property poses an issue for surface modification. In this case, laser radiation would not be absorbed at the surface unless the beam is just focused there. Otherwise, absorption would take place in the bulk leaving the surface unperturbed. Therefore, strategies to position the material surface at the laser beam waist with high accuracy are essential. We investigated and compared two options to achieve this aim: the use of reflectance data and transmittance measurements across the sample, both obtained during z-scans with pulses from a 1027 nm wavelength laser and 450 fs pulse duration. As the material enters the beam waist region, a reflectance peak is detected while a transmittance drop is observed. With these observations, it is possible to control the position of the sample surface with respect to the beam waist with high resolution and attain pure surface modification. In the case of polymethyl-methacrylate (PMMA), this resolution is 0.6 μm. The results prove that these methods are feasible for submicrometric processing of the surface.

  20. Customized Cranioplasty Implants Using Three-Dimensional Printers and Polymethyl-Methacrylate Casting

    PubMed Central

    Kim, Bum-Joon; Hong, Ki-Sun; Park, Kyung-Jae; Park, Dong-Hyuk; Chung, Yong-Gu

    2012-01-01

    Objective The prefabrication of customized cranioplastic implants has been introduced to overcome the difficulties of intra-operative implant molding. The authors present a new technique, which consists of the prefabrication of implant molds using three-dimensional (3D) printers and polymethyl-methacrylate (PMMA) casting. Methods A total of 16 patients with large skull defects (>100 cm2) underwent cranioplasty between November 2009 and April 2011. For unilateral cranial defects, 3D images of the skull were obtained from preoperative axial 1-mm spiral computed tomography (CT) scans. The image of the implant was generated by a digital subtraction mirror-imaging process using the normal side of the cranium as a model. For bilateral cranial defects, precraniectomy routine spiral CT scan data were merged with postcraniectomy 3D CT images following a smoothing process. Prefabrication of the mold was performed by the 3D printer. Intraoperatively, the PMMA implant was created with the prefabricated mold, and fit into the cranial defect. Results The median operation time was 184.36±26.07 minutes. Postoperative CT scans showed excellent restoration of the symmetrical contours and curvature of the cranium in all cases. The median follow-up period was 23 months (range, 14-28 months). Postoperative infection was developed in one case (6.2%) who had an open wound defect previously. Conclusion Customized cranioplasty PMMA implants using 3D printer may be a useful technique for the reconstruction of various cranial defects. PMID:23346326

  1. Radiological evaluation of acetabular erosion after antibiotic-impregnated polymethylmethacrylate spacer (Spacer-G).

    PubMed

    García-Oltra, Ester; Bori, Guillem; Tomas, Xavier; Gallart, Xavier; Garcia, Sebastian; Soriano, Alex

    2013-06-01

    Different types of hip spacers have been described (hand-made, custom-molded or prefabricated) for treatment of a chronic hip infection. A potential disadvantage of monoblock prefabricated spacer is that it may cause acetabular bone loss. This study assesses the radiological acetabular erosion using an antibiotic-impregnated pre-fabricated polymethylmethacrylate Spacer-G. We retrospectively reviewed the radiographs of thirty five patients who were managed with Spacer-G to treat chronic hip infection. No acetabular erosion were observed in thirty two patients with a mean time from the first to second stage and from the first to the last radiograph of 5.09 and 3.77 months respectively. In three patients the time between the radiographs was more than one year and the second stage was not performed; two developed a protrusion acetabuli whereas the other one a destruction of the acetabular roof. Using a Spacer-G in chronic hip infection treatment for less than one year is not associated with radiological acetabular erosion if the patient is maintained at partial weight bearing. PMID:23142448

  2. Ablation of bone and polymethylmethacrylate by an XeCl (308 nm) excimer laser

    SciTech Connect

    Yow, L.; Nelson, J.S.; Berns, M.W.

    1989-01-01

    One of the main problems in orthopaedics is the surgical removal of hard substances, such as bone and polymethylmethacrylate (PMMA). Such materials are often very difficult to remove without mechanical trauma to the remaining tissue. This study investigated the feasibility of the ultraviolet 308 nm excimer laser in the ablation of these materials. The beam was delivered through a 1 mm-diameter fiber optic at 40 Hz with energy densities at the target surface of 20-80 J/cm2 per pulse. The goal of the study was to establish the ideal dosimetry for removing bone and PMMA with minimum trauma to the adjacent tissue. Histology revealed that the 308 nm laser effectively removed bone leaving a thermal damage zone of only 2-3 microns in the remaining tissue. Increasing the energy per pulse gave correspondingly larger and deeper cuts with increasing zones of thermal damage. The excimer laser was also effective in the ablation of PMMA, creating craters in the substrate with a thermal damage zone of 10-40 microns. The debris from both substrates was evaluated.

  3. Antibiotic-releasing porous polymethylmethacrylate/gelatin/antibiotic constructs for craniofacial tissue engineering.

    PubMed

    Shi, Meng; Kretlow, James D; Spicer, Patrick P; Tabata, Yasuhiko; Demian, Nagi; Wong, Mark E; Kasper, F Kurtis; Mikos, Antonios G

    2011-05-30

    An antibiotic-releasing porous polymethylmethacrylate (PMMA) construct was developed to maintain the bony space and prime the wound site in the initial step of a two-stage regenerative medicine approach toward reconstructing significant bony or composite craniofacial tissue defects. Porous PMMA constructs incorporating gelatin microparticles (GMPs) were fabricated by the sequential assembly of GMPs, the antibiotic colistin, and a clinically used bone cement formulation of PMMA powder and methylmethacrylate liquid. PMMA/gelatin/antibiotic constructs with varying gelatin incorporation and drug content were investigated to elucidate the relationship between material composition and construct properties (porosity and drug release kinetics). The porosity of PMMA/gelatin/antibiotic constructs ranged between 7.6±1.8% and 38.4±1.4% depending on the amount of gelatin incorporated and the drug solution added for gelatin swelling. The constructs released colistin over 10 or 14 days with an average release rate per day above 10 μg/ml. The porosity and in vitro colistin release kinetics of PMMA/gelatin/antibiotic constructs were tuned by varying the material composition and fabrication parameters. This study demonstrates the potential of gelatin-incorporating PMMA constructs as a functional space maintainer for both promoting tissue healing/coverage and addressing local infections, enabling better long-term success of the definitive regenerated tissue construct. PMID:21295086

  4. Evaluation of antibiotic releasing porous polymethylmethacrylate space maintainers in an infected composite tissue defect model.

    PubMed

    Spicer, Patrick P; Shah, Sarita R; Henslee, Allan M; Watson, Brendan M; Kinard, Lucas A; Kretlow, James D; Bevil, Kristin; Kattchee, Lauren; Bennett, George N; Demian, Nagi; Mende, Katrin; Murray, Clinton K; Jansen, John A; Wong, Mark E; Mikos, Antonios G; Kasper, F Kurtis

    2013-11-01

    This study evaluated the in vitro and in vivo performance of antibiotic-releasing porous polymethylmethacrylate (PMMA)-based space maintainers comprising a gelatin hydrogel porogen and a poly(dl-lactic-co-glycolic acid) (PLGA) particulate carrier for antibiotic delivery. Colistin was released in vitro from either gelatin or PLGA microparticle loaded PMMA constructs, with gelatin-loaded constructs releasing colistin over approximately 7 days and PLGA microparticle-loaded constructs releasing colistin for up to 8 weeks. Three formulations with either burst release or extended release at different doses were tested in a rabbit mandibular defect inoculated with Acinetobacter baumannii (2×10(7) colony forming units ml(-1)). In addition, one material control that released antibiotic but was not inoculated with A. baumannii was tested. A. baumannii was not detectable in any animal after 12 weeks on culture of the defect, saliva, or blood. Defects with high dose extended release implants had greater soft tissue healing compared with defects with burst release implants, with 8 of 10 animals showing healed mucosae compared with 2 of 10 respectively. Extended release of locally delivered colistin via a PLGA microparticle carrier improved soft tissue healing compared with implants with burst release of colistin from a gelatin carrier. PMID:23891810

  5. Polymethylmethacrylate (PMMA) Material Test Results for the Capillary Flow Experiments (CFE)

    NASA Technical Reports Server (NTRS)

    Lerch, Bradley A.; Thesken, John C.; Bunnell, Charles T.

    2007-01-01

    In support of the Capillary Flow Experiments (CFE) program, several polymethylmethacrylate (PMMA) flight vessels were constructed. Some vessels used a multipiece design, which was chemically welded together. Due to questions regarding the effects of the experiment fluid (silicone oil) on the weld integrity, a series of tests were conducted to provide evidence of the adequacy of the current vessel design. Tensile tests were conducted on PMMA samples that were both in the as-received condition, and also aged in air or oil for up to 8 weeks. Both welded and unwelded samples were examined. Fracture of the joints was studied using notched tensile specimens and Brazilian disk tests. Results showed that aging had no effect on tensile properties. While the welded samples were weaker than the base parent material, the weld strength was found to be further degraded by bubbles in the weld zone. Finally a fracture analysis using the worst-case fracture conditions of the vessel was performed, and the vessel design was found to have a factor of three safety margin.

  6. Near Surface Vapor Bubble Layers in Buoyant Low Stretch Burning of Polymethylmethacrylate

    NASA Technical Reports Server (NTRS)

    Olson, Sandra L.; Tien, J. S.

    1999-01-01

    Large-scale buoyant low stretch stagnation point diffusion flames over solid fuel (polymethylmethacrylate) were studied for a range of aerodynamic stretch rates of 2-12/ sec which are of the same order as spacecraft ventilation-induced stretch in a microgravity environment. An extensive layer of polymer material above the glass transition temperature is observed. Unique phenomena associated with this extensive glass layer included substantial swelling of the burning surface, in-depth bubble formation, and migration and/or elongation of the bubbles normal to the hot surface. The bubble layer acted to insulate the polymer surface by reducing the effective conductivity of the solid. The reduced in-depth conduction stabilized the flame for longer than expected from theory neglecting the bubble layer. While buoyancy acts to move the bubbles deeper into the molten polymer, thermocapillary forces and surface regression both act to bring the bubbles to the burning surface. Bubble layers may thus be very important in low gravity (low stretch) burning of materials. As bubbles reached the burning surface, monomer fuel vapors jetted from the surface, enhancing burning by entraining ambient air flow. Popping of these bubbles at the surface can expel burning droplets of the molten material, which may increase the fire propagation hazards at low stretch rates.

  7. Ignition transient of a polymethylmethacrylate slab in a sudden-expansion combustor

    SciTech Connect

    Yang, J.T.; Wu, C.Y.Y.; Din, S.J. . Dept. of Power Mechanical Engineering)

    1994-08-01

    Ignition and the subsequent flame development of a polymethylmethacrylate (PMMA) slab in a sudden-expansion combustor was observed experimentally. The solid fuel was ignited by a hot oxidizing flow stream that was supplied by a wind tunnel. The controlled variables of the experiment were: step height (17--29 mm), inlet flow velocity (15--30 m/s), and inlet gas temperature (700--850 C). The oxygen concentration of the gas stream was 13%. The ignition process generally initiated in the recirculation zone, but occasionally occurred near the end of the fuel slab at high temperature of the gas and small velocity of the flow. The results show that high temperature and a high step height favored ignition, broadened the ignition limits and abbreviated the ignition delay. The interval of the flame development was about 0.1 s when ignition occurred in the recirculation zone but 0.9 s for ignition near the end of the fuel slab. As the step height increased, the opposed flame spread rate increased, but the rate of concurrent flame spread decreased. In this work, the rate of opposed flame spread was 0.2--7.7 m/s and that of concurrent flame spread was 9.6--18.3 m/s.

  8. Polymethylmethacrylate-augmented screw fixation for stabilization in metastatic spinal tumors. Technical note.

    PubMed

    Jang, Jee Soo; Lee, Sang Ho; Rhee, Chang Hun; Lee, Seung Hoon

    2002-01-01

    Screw fixation augmented with polymethylmethacrylate (PMMA) or some other biocompatible bone cement has been used in patients with osteoporosis requiring spinal fusion. No clinical studies have been conducted on PMMA-augmented screw fixation for stabilization of the vertebral column in patients with metastatic spinal tumors. The purpose of this study was to determine whether screw fixation augmented with PMMA might be suitable in patients treated for multilevel metastatic spinal tumors. Ten patients with metastatic spinal tumors involving multiple vertebral levels underwent stabilization procedures in which PMMA was used to augment screw fixation after decompression of the spinal cord. Within 15 days, partial or complete relief from pain was obtained in all patients postoperatively. Two of four patients in whom neurological deficits caused them to be nonambulatory before surgery were able to ambulate postoperatively. Neither collapse of the injected vertebral bodies nor failure of the screw fixation was observed during the mean follow-up period of 6.7 months. Screw fixation augmented with PMMA may offer stronger stabilization and facilitate the instrumentation across short segments in the treatment of multilevel metastatic spinal tumors. PMID:11795702

  9. High speed Radix-4 soft-decision Viterbi decoder for MB-OFDM UWB system

    NASA Astrophysics Data System (ADS)

    Liang, Guixuan; Portilla, Jorge; Riesgo, Teresa

    2013-05-01

    In this paper, a 64 state soft decision Viterbi Decoder (VD) system by using a high speed radix-4 Add Compare Select (ACS) architecture is presented. The proposed VD system can support different data rate (from 53.5 Mbps to 480 Mbps) for Multiband Orthogonal Frequency-division Multiplexing (MB-OFDM) Ultra-Wideband (UWB) system when implemented onto the FPGA board. The proposed VD employs efficient two steps Radix 4 architecture, which is responsible of calculating two steps of 64 state Radix 4 Branch Metrics (BM) within one clock cycle. The branch metrics are calculated using a uniform distance measurement algorithm, which equals to the symbol itself when compared to logic-0 and equal to its one's complement when compared to logic-1. By employing the modified Modulo Normalization algorithm, it is possible to use only a 10- bit memory block to restore each of the 64 state metrics, with the advantage of avoiding errors caused by overflow during the updating process for state metrics, and simplifying the comparator circuit of the ACS unit. The Two Pointer Even Algorithm, which is considered to be very simple and more hardware-efficient than the register exchange algorithm, is used for tracing back the survivor sequence and output the decoded data stream. 3-bit soft decision input sequences are used for gathering the experimental results. The sampling frequency of the MBOFDM UWB system is 528 MHz, by using the proposed two steps Radix 4 VD architecture we can process 4 input signals in parallel within one clock cycle, therefore only 132 MHz operating frequency is needed for the proposed VD system. This will dramatically reduce the dynamic power consumption for hardware implementation. Final results of the implementation show that the proposed VD architecture can support a maximum working frequency of 152.5 MHz on Xilinx XUPV5-LX110T Evaluation Platform.

  10. Method and apparatus for reading free falling dosimeter punchcodes

    DOEpatents

    Langsted, J.M.

    1992-12-22

    A punchcode reader is provided for reading data encoded in a punchcode hole array on a dosimeter. The dosimeter falls through a passage in the reader containing photosensor detectors disposed along the passage which provide output signals to a microprocessor. The signals are processed to determine the orientation of the dosimeter in the reader, the location and state of punchcode holes in a two row array thereby decoding the encoded data. Multiple rate of fall calculations are made, and if appropriate matching of the punchcode array is not obtained in three tries, an error signal is output to the operator. The punchcode reader also provides for storage of data from multiple dosimeters passed through the reader, and for the output of decoded data to an external display or a computer for further processing. 8 figs.

  11. Method and apparatus for reading free falling dosimeter punchcodes

    DOEpatents

    Langsted, James M.

    1992-12-22

    A punchcode reader is provided for reading data encoded in a punchcode hole array on a dosimeter. The dosimeter falls through a passage in the reader containing photosensor detectors disposed along the passage which provide output signals to a microprocessor. The signals are processed to determine the orientation of the dosimeter in the reader, the location and state of punchcode holes in a two row array thereby decoding the encoded data. Multiple rate of fall calculations are made, and if appropriate matching of the punchcode array is not obtained in three tries, an error signal is outputted to the operator. The punchcode reader also provides for storage of data from multiple dosimeters passed through the reader, and for the output of decoded data to an external display or a computer for further processing.

  12. Antioxidant effect of green tea on polymer gel dosimeter

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

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

  13. The Development of a Beta-Gamma Personnel Dosimeter

    NASA Astrophysics Data System (ADS)

    Tsakeres, Frank Steven

    The assessment of absorbed dose in mixed beta and gamma radiation fields is an extremely complex task. For many years, the assessment of the absorbed dose to tissue from the weakly penetrating components of a radiation field (i.e., beta particles, electrons) has been largely ignored. Beta radiation fields are encountered routinely in a nuclear facility and may represent the major radiation component under certain accident or emergency conditions. Many attempts have been made to develop an accurate mixed field personnel dosimeter. However, all of these dosimeters have exhibited numerous response problems which have limited their usefulness for personnel dose assessment. Consequently, the determination of the absorbed dose at the epidermal depth (i.e., 7 mg/cm('2)) has been difficult to measure accurately. The objective of this research project was to design, build, and test a sensitive and accurate personnel dosimeter for mixed field applications. The selection of the various dosimeter elements were determined by evaluating several types of phosphors, filters, and backscatter materials. After evaluating the various response characteristics of the badge components, a prototype dosimeter, the CHEMM (CaF(,2):Dy Highly Efficient Multiple Element Multiple Filter) personnel dosimeter, was developed and tested at Georgia Tech, Emory University and the National Bureau of Standards. This dosimeter was comprised of four large CaF(,2):Dy (TLD-200) TLD's and a standard LiF (TLD-100) chip. The weakly penetrating and penetrating components of a radiation field were separated using a series of TLD/filter combinations and a new dose assessment algorithm. The large TLD-200 chips, along with a series of tissue-equivalent filters, were used to determine the absorbed dose due to the weakly penetrating radiation while a LiF/filter combination was used to measure the penetrating component. In addition, a new backscatter material was included in the badge design to better simulate a

  14. Glycyrrhizae Radix Methanol Extract Attenuates Methamphetamine-Induced Locomotor Sensitization and Conditioned Place Preference

    PubMed Central

    Zhao, ZhengLin; Zhang, Jie; Jung, Ji Yun; Chang, Suchan; Zhou, FuBo; Zhao, JunChang; Lee, Bong Hyeo; Yang, Chae Ha; Zhao, RongJie

    2014-01-01

    Glycyrrhizae Radix modulates the neurochemical and locomotor alterations induced by acute psychostimulants in rodents via GABAb receptors. This study investigated the influence of methanol extract from Glycyrrhizae Radix (MEGR) on repeated methamphetamine- (METH-) induced locomotor sensitization and conditioned place preference (CPP). A cohort of rats was treated with METH (1 mg/kg/day) for 6 consecutive days, subjected to 6 days of withdrawal, and then challenged with the same dose of METH to induce locomotor sensitization; during the withdrawal period, the rats were administered MEGR (60 or 180 mg/kg/day). A separate cohort of rats was treated with either METH or saline every other day for 6 days in METH-paired or saline-paired chambers, respectively, to induce CPP. These rats were also administered MEGR (180 mg/kg) prior to every METH or CPP expression test. Pretreatment with MEGR (60 and 180 mg/kg/day) attenuated the expression of METH-induced locomotor sensitization dose-dependently, and 180 mg/kg MEGR significantly inhibited the development and expression of METH-induced CPP. Furthermore, administration of a selective GABAb receptor antagonist (SCH50911) prior to MEGR treatment effectively blocked the inhibitory effects of MEGR on locomotor sensitization, but not CPP. These results suggest that Glycyrrhizae Radix blocked repeated METH-induced behavioral changes via GABAb receptors. PMID:25386216

  15. Microscopic research on a multi-source traditional Chinese medicine, Astragali Radix.

    PubMed

    Yu, Kun-Zi; Liu, Jing; Guo, Bao-Lin; Zhao, Zhong-Zhen; Hong, Hao; Chen, Hu-Biao; Cai, Shao-Qing

    2014-04-01

    Astragali Radix is a widely and commonly used Chinese herbal medicine, which is derived from roots of Astragalus membranaceus var. mongholicus and Astragalus membranaceus. To find a quick and reliable method of distinguishing these two species of Astragali Radix and of determining the age of a sample, microscopic characteristics of the two species were compared using light microscopy. The results showed that the microscopic characteristics, such as number of layers of phellem, continuing lignified xylem bundles within spring wood and lignified parenchyma cells in the central part of the xylem could be used for the differentiation of the root of A. membranaceus from the root of A. membranaceus var. mongholicus. Growth rings (annual rings) were found for the first time in the roots of both species, and could determine the age of a sample. For the first time, radial fibers in both species of Astragali Radix and pipette-shaped fibers in A. membranaceus var. mongholicus were found. The structure of "rotten heart" cork tissue (decayed central xylem) and tubular cork tissue was carefully studied, and the arranged order of tissues in both "rotten heart" and tubular cork tissues is phelloderm and phellem from outside to inside, which is contrary to that in the periderm. PMID:24085529

  16. Simultaneous quantitative analysis of main components in linderae reflexae radix with one single marker

    PubMed Central

    Wang, Li-li; Zhang, Yun-bin; Sun, Xiao-ya; Chen, Sui-qing

    2016-01-01

    ABSTRACT Establish a quantitative analysis of multi-components by the single marker (QAMS) method for quality evaluation and validate its feasibilities by the simultaneous quantitative assay of four main components in Linderae Reflexae Radix. Four main components of pinostrobin, pinosylvin, pinocembrin, and 3,5-dihydroxy-2-(1-p-mentheneyl)-trans-stilbene were selected as analytes to evaluate the quality by RP-HPLC coupled with a UV-detector. The method was evaluated by a comparison of the quantitative results between the external standard method and QAMS with a different HPLC system. The results showed that no significant differences were found in the quantitative results of the four contents of Linderae Reflexae Radix determined by the external standard method and QAMS (RSD <3%). The contents of four analytes (pinosylvin, pinocembrin, pinostrobin, and Reflexanbene I) in Linderae Reflexae Radix were determined by the single marker of pinosylvin. This fingerprint was the spectra determined by Shimadzu LC-20AT and Waters e2695 HPLC that were equipped with three different columns. PMID:27366022

  17. [Optimization of extraction technology from Paeoniae Radix Alba using response surface methodology].

    PubMed

    Jin, Lin; Zhao, Wan-shun; Guo, Qiao-sheng; Zhang, Wen-sheng; Ye, Zheng-liang

    2015-08-01

    To ensure the stability of chemistry components and the convenience of operation, ultrasound method was chosen to study in this investigation. As the total common peaks area in chromatograms was set to be evaluation index, the influence on the technology caused by extraction time, ethanol concentration and liquid-to-solid ratio was studied by using single factor methodology, and the extraction technology of Paeoniae Radix Alba was optimized by using response surface methodology. The results showed that the extracting results were most affected by ethanol concentration; liquid-to-solid ratio came the second and extraction time thirdly. The optimum ultrasonic-assisted extraction conditions were as follow: the ultrasonic extraction time was 20.06 min, the ethanol concentration in solvent was 72.04%, and the liquid-to-solid ratio was 53.38 mL · g(-1), the predicted value of total common peaks area was 2.1608 x 10(8). Under the extraction conditions after optimization, the total common peaks area was 2.1422 x 10(8), and the relative deviation between the measured and predicted value was 0.86%, so the optimized extraction technology for Paeoniae Radix Alba is suitable and feasible. Besides, for the purpose of extracting more sufficiently and completely, the optimized extraction technology had more advantages than the extraction method recorded in the monogragh of Paeoniae Radix Alba in Chinese Pharmacopoeia, which will come true the assessment and utilization comprehensively. PMID:26677698

  18. Preparative separation of minor saponins from Platycodi Radix by high-speed counter-current chromatography.

    PubMed

    Ha, In J; Kang, Minseok; Na, Yun C; Park, Youmie; Kim, Yeong S

    2011-10-01

    Platycosides (PSs), the saponins found in the root of Platycodon grandiflorum (Jacq.) A. DC. (Platycodi Radix), are typically composed of oleanene backbones with two side chains; one is a 3-O-glucose linked by a glycosidic bond, and the other is a 28-O-arabinose-rhamnose-xylose-apiose linked by an ester bond. Minor saponins, acetylated isomers of the major saponin on either the 2'' or 3'' position of rhamnose, were isolated from Platycodi Radix using a multi-step process including high-speed counter-current chromatography (HSCCC) and preparative reversed-phase high-performance liquid chromatography (RP-HPLC). After the separation of the major components, the enriched minor saponin fraction was used for this study. A two-phase solvent system consisting of chloroform-methanol-isopropanol-water (3:2:2:3, v/v) was used for HSCCC. HSCCC separation of the enriched minor saponin fraction yielded 2''-O-acetylplatycodin D, 3''-O-acetylpolygalacin D, 2''-O-acetylpolygalacin and a mixture of 3''-O-acetylplatycodin D and polygalacin D. The mixture fraction from HSCCC separation was further purified by preparative RP-HPLC, giving 3''-O-acetylplatycodin D and polygalacin D at a purity of over 98.9%. The developed method provides the preparative and rapid separation of minor saponins in the crude extract of Platycodi Radix. To the best of our knowledge, this is the first on the separation of acetylated PSs by HSCCC. PMID:21812112

  19. Toxicological safety and stability of the components of an irradiated Korean medicinal herb, Paeoniae Radix

    NASA Astrophysics Data System (ADS)

    Yu, Young-Beob; Jeong, Ill-Yun; Park, Hae-Ran; Oh, Heon; Jung, Uhee; Jo, Sung-Kee

    2004-09-01

    As utilization of medicinal herbs in food and bio-industry increases, mass production and the supply of herbs with a high quality are required. As the use of fumigants and preservatives for herbs is being restricted, safe hygienic technologies are demanded. To consider the possibility of the application of irradiation technology for this purpose, the genotoxicological safety and stability of the active components of the γ-irradiated Paeoniae Radix were studied. The herb was irradiated with γ-rays at a practical dosage of 10 kGy, and then it was extracted with hot water. The genotoxicity of the extract of the irradiated herb was examined in two short-term in vitro tests: (1) Ames test in Salmonella typhimurium; (2) Micronucleus test in cultured Chinese hamster ovary (CHO) cells. The extract of the irradiated herb did not show mutagenicity in the Ames test of the Salmonella reverse mutation assay, and did not show cytogenetic toxicity in the culture of the CHO cells. HPLC chromatogram of paeoniflorin in the irradiated Paeoniae Radix was similar with that of the non-irradiated sample. The quantity of paeoniflorin did not change significantly with irradiation. These results suggest that γ-irradiated Paeoniae Radix is toxicologically safe and chemically stable.

  20. Surface-enhanced Raman scattering (SERS) dosimeter and probe

    DOEpatents

    Vo-Dinh, T.

    1995-03-21

    A dosimeter and probe for measuring exposure to chemical and biological compounds is disclosed. The dosimeter or probe includes a collector which may be analyzed by surface-enhanced Raman spectroscopy. The collector comprises a surface-enhanced Raman scattering-active material having a coating applied thereto to improve the adsorption properties of the collector. The collector may also be used in automated sequential devices, in probe array devices. 10 figures.

  1. Methods and means of checking thermoluminescent and radiophotoluminescent dosimeters

    SciTech Connect

    Fominykh, V.I.; Oborin, A.V.; Sebekin, A.P.; Uryaev, I.A.

    1987-06-01

    The authors discuss methods of checking thermoluminescent and radiophotoluminescent dosimeters which are used often in monitoring radiation safety in various areas including nuclear power stations. When the dosimeters are checked in the fields of standard beta-ray sources, it is recommended that the standard absorbed-dose or equivalent-dose measures for beta radiation should be sources of /sup 90/Sr + /sup 90/Y, /sup 204/Tl, and /sup 147/Pm. Various safety guidelines are discussed.

  2. Surface-enhanced Raman scattering (SERS) dosimeter and probe

    DOEpatents

    Vo-Dinh, Tuan

    1995-01-01

    A dosimeter and probe for measuring exposure to chemical and biological compounds is disclosed. The dosimeter or probe includes a collector which may be analyzed by surface-enhanced Raman spectroscopy. The collector comprises a surface-enhanced Raman scattering-active material having a coating applied thereto to improve the adsorption properties of the collector. The collector may also be used in automated sequential devises, in probe array devices.

  3. Freshwater Biogeography and Limnological Evolution of the Tibetan Plateau - Insights from a Plateau-Wide Distributed Gastropod Taxon (Radix spp.)

    PubMed Central

    von Oheimb, Parm Viktor; Albrecht, Christian; Riedel, Frank; Du, Lina; Yang, Junxing; Aldridge, David C.; Bößneck, Ulrich; Zhang, Hucai; Wilke, Thomas

    2011-01-01

    Background The Tibetan Plateau is not only the highest and largest plateau on earth; it is also home to numerous freshwater lakes potentially harbouring endemic faunal elements. As it remains largely unknown whether these lakes have continuously existed during the Last Glacial Maximum (LGM), questions arise as to whether taxa have been able to exist on the plateau since before the latest Pleistocene, from where and how often the plateau was colonized, and by which mechanisms organisms conquered remote high altitude lentic freshwater systems. In this study, species of the plateau-wide distributed freshwater gastropod genus Radix are used to answer these biogeographical questions. Methodology/Principal Findings Based on a broad spatial sampling of Radix spp. on the Tibetan Plateau, and phylogenetic analyses of mtDNA sequence data, three probably endemic and one widespread major Radix clade could be identified on the plateau. Two of the endemic clades show a remarkably high genetic diversity, indicating a relatively great phylogenetic age. Phylogeographical analyses of individuals belonging to the most widely distributed clade indicate that intra-plateau distribution cannot be explained by drainage-related dispersal alone. Conclusions/Significance Our study reveals that Radix spp. persisted throughout the LGM on the Tibetan Plateau. Therefore, we assume the continuous existence of suitable water bodies during that time. The extant Radix diversity on the plateau might have been caused by multiple colonization events combined with a relatively long intra-plateau evolution. At least one colonization event has a Palaearctic origin. In contrast to freshwater fishes, passive dispersal, probably by water birds, might be an important mechanism for conquering remote areas on the plateau. Patterns found in Radix spp. are shared with some terrestrial plateau taxa, indicating that Radix may be a suitable model taxon for inferring general patterns of biotic origin, dispersal and

  4. Potential High Resolution Dosimeters For MRT

    NASA Astrophysics Data System (ADS)

    Bräuer-Krisch, E.; Rosenfeld, A.; Lerch, M.; Petasecca, M.; Akselrod, M.; Sykora, J.; Bartz, J.; Ptaszkiewicz, M.; Olko, P.; Berg, A.; Wieland, M.; Doran, S.; Brochard, T.; Kamlowski, A.; Cellere, G.; Paccagnella, A.; Siegbahn, E. A.; Prezado, Y.; Martinez-Rovira, I.; Bravin, A.; Dusseau, L.; Berkvens, P.

    2010-07-01

    resolution and a dose range over several orders of magnitude. This paper will give an overview of all dosimeters tested in the past at the ESRF with their advantages and drawbacks. These detectors comprise: Ionization chambers, Alanine Dosimeters, MOSFET detectors, Gafchromic® films, Radiochromic polymers, TLDs, Polymer gels, Fluorescent Nuclear Track Detectors (Al2O3:C, Mg single crystal detectors), OSL detectors and Floating Gate-based dosimetry system. The aim of such a comparison shall help with a decision on which of these approaches is most suitable for high resolution dose measurements in MRT. The principle of these detectors will be presented including a comparison for some dosimeters exposed with the same irradiation geometry, namely a 1×1 cm5 field size with microbeam exposures at the surface, 0.1 cm and 1 cm in depth of a PMMA phantom. For these test exposures, the most relevant irradiation parameters for future clinical trials have been chosen: 50 micron FWHM and 400 micron c-t-c distance. The experimental data are compared with Monte Carlo calculations.

  5. Potential High Resolution Dosimeters For MRT

    SciTech Connect

    Braeuer-Krisch, E.; Brochard, T.; Prezado, Y.; Bravin, A.; Berkvens, P.; Rosenfeld, A.; Lerch, M.; Petasecca, M.; Akselrod, M.; Sykora, J.; Bartz, J.; Ptaszkiewicz, M.; Olko, P.; Berg, A.; Wieland, M.; Doran, S.; Kamlowski, A.; Cellere, G.

    2010-07-23

    /s, micron resolution and a dose range over several orders of magnitude. This paper will give an overview of all dosimeters tested in the past at the ESRF with their advantages and drawbacks. These detectors comprise: Ionization chambers, Alanine Dosimeters, MOSFET detectors, Gafchromic registered films, Radiochromic polymers, TLDs, Polymer gels, Fluorescent Nuclear Track Detectors (Al{sub 2}O{sub 3}:C, Mg single crystal detectors), OSL detectors and Floating Gate-based dosimetry system. The aim of such a comparison shall help with a decision on which of these approaches is most suitable for high resolution dose measurements in MRT. The principle of these detectors will be presented including a comparison for some dosimeters exposed with the same irradiation geometry, namely a 1x1 cm{sup 5} field size with microbeam exposures at the surface, 0.1 cm and 1 cm in depth of a PMMA phantom. For these test exposures, the most relevant irradiation parameters for future clinical trials have been chosen: 50 micron FWHM and 400 micron c-t-c distance. The experimental data are compared with Monte Carlo calculations.

  6. Fast neutron dosimeter using Cooled Optically Stimulated Luminescence (COSL)

    SciTech Connect

    Eschbach, P.A.; Miller, S.D.

    1991-10-01

    Data is presented that demonstrates the concept of a fast neutron dosimeter using Cooled Optically Stimulated Luminescence. CaF{sub 2}:Mn powder, compounded with polyethylene, was injection molded and pressed into 0.1-cm-thick sheets. The sheets were then cut to form dosimeters with dimensions, 1.25 cm by 1.25 cm. After a laser anneal, the dosimeters were exposed to various amounts (from 10 mSv to 100 mSv) of fast {sup 252}Cf neutrons. The exposed dosimeters were cooled to liquid nitrogen temperature, stimulated with laser light, and then allowed to warm up to room temperature whereupon the dose dependent luminescence was recorded with a photon counting system. When the control and gamma components were subtracted from the {sup 252}Cf response, a dose-dependent neutron response was observed. The design, construction, and preliminary performance of an automated system for the dose interrogation of individual CaF{sub 2}:Mn grains within the polyethylene matrix will also be discussed. The system uses a small CO{sub 2} laser to heat areas of the cooled dosimeter to room temperature. If the readout of very small grain within the plastic matrix is successful, it will enhance the neutron to gamma response of the dosimeter.

  7. Radiation measured with passive dosimeters in low Earth orbit

    NASA Astrophysics Data System (ADS)

    Zhou, D.; Semones, E.; Gaza, R.; Weyland, M.

    begin center Radiation Measured with Passive Dosimeters in Low Earth Orbit end center begin center D Zhou 1 2 E Semones 1 R Gaza 1 2 M Weyland 1 end center begin center 1 Johnson Space Center - NASA 2101 Nasa Road 1 Houston 77058 USA end center begin center 2 Universities Space Research Association 2101 Nasa Parkway Houston 77058 USA end center begin center Abstract end center The linear energy transfer LET of particles in low Earth orbit LEO is extended from sim 0 1 to sim 1000 keV mu m water The best passive dosimeters for the radiation measurement are thermoluminescence dosimeters TLDs or optically stimulated luminescence dosimeters OSLDs for low LET and CR-39 plastic nuclear track detectors PNTDs for high LET Radiation quantities fluence absorbed dose dose equivalent and quality factor were measured with the passive dosimeters composed of TLDs OSLDs and CR-39 PNTDs for STS-114 mission This paper introduces the operation principles for TLDs OSLDs and CR-39 PNTDs describes the method to combine the results measured by TLDs OSLDs and CR-39 PNTDs and presents the results measured by different dosimeters for different LET band and that combined for all LET

  8. Response of the Hanford Combination Neutron Dosimeter in plutonium environments

    SciTech Connect

    Endres, A.W.; Brackenbush, L.W.; Baumgartner, W.V.

    1996-02-01

    This report documents response characteristics and the development of dose algorithms for the Hanford Combination Neutron Dosimeter (HCNO) implemented on January 1, 1995. The HCND was accredited under the U.S. Department of Energy (DOE) Laboratory Accreditation Program (DOELAP) during 1994. The HCND employs two neutron dose components consisting of (1) an albedo thermoluminescent dosimeter (TLD), and (2) a track-etch dosimeter (TED). Response characteristics of these two dosimeter components were measured under the low-scatter conditions of the Hanford 318 Building Calibration Laboratory, and under the high-scatter conditions in the workplace at the Plutonium Finishing Plant (PFP). The majority of personnel neutron dose at Hanford (currently and historically) occurs at the PFP. National Institute of Standards and Technology (NIST) traceable sources were used to characterize dosimeter response in the laboratory. At the PFP, neutron spectra and dose-measuring instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters, were used to determine the neutron dose under several configurations from three different plutonium sources: (1) plutonium tetrafluoride, (2) plutonium metal, and (3) plutonium oxide. In addition, measurements were performed at many selected work locations. The HCNDs were included in all measurements. Comparison of dosimeter- and instrument-measured dose equivalents provided the data necessary to develop HCND dose algorithms and to assess the accuracy of estimated neutron dose under actual work conditions.

  9. Comparative analysis of the constituents in Saposhnikoviae Radix and Glehniae Radix cum Rhizoma by monitoring inhibitory activity of nitric oxide production.

    PubMed

    Kamino, Takuya; Shimokura, Toshihiro; Morita, Yusuke; Tezuka, Yasuhiro; Nishizawa, Mikio; Tanaka, Ken

    2016-04-01

    During the development of natural herbal medicines in Japan, Glehniae Radix cum Rhizoma (Hamabofu in Japanese) has been used as a substitute for Saposhnikoviae Radix (Bofu). Bofu and Hamabofu are blended differently in several Kampo formulae. For example, Bofu is included in Jumihaidokuto by a manufacturer, whereas Hamabofu is included instead of Bofu in the same formula by other manufacturers. Although both Bofu and Hamabofu are used for their expected anti-inflammatory effects, differences in their medicinal properties are not well characterized. In addition, there have been very few reports comparing the pharmacological activities of the constituents in Bofu and Hamabofu. In the present study, we investigated the anti-inflammatory effects of the extracts of Bofu and Hamabofu by monitoring levels of the inflammatory mediator nitric oxide (NO) produced in rat hepatocytes. Moreover, the chemical constituents responsible for the activity were investigated. Our results showed that ethyl acetate fractions of Bofu and Hamabofu extracts contain different compounds, although both fractions suppressed NO production in rat hepatocytes. The linear dihydropyranochromones from the Bofu extract (i.e., 3'-O-angeloylhamaudol, ledebouriellol and hamaudol) suppressed NO production, whereas the coumarins from the Hamabofu extract (i.e., umbelliferone and scopoletin) also suppressed NO production. These results suggest that linear dihydropyranochromones and coumarins are responsible for the anti-inflammatory effects of Bofu and Hamabofu. It is plausible that Bofu and Hamabofu are blended differently in several Kampo formulae due to many constituents with as yet unidentified pharmacological activity. PMID:26833192

  10. Ethanolic Extract of Astragali Radix and Salviae Radix Prohibits Oxidative Brain Injury by Psycho-Emotional Stress in Whisker Removal Rat Model

    PubMed Central

    Kim, Hyeong-Geug; Lee, Jin-Seok; Choi, Min-Kyung; Han, Jong-Min; Son, Chang-Gue

    2014-01-01

    Myelophil, an ethanolic extract of Astragali Radix and Salviae Radix, has been clinically used to treat chronic fatigue and stress related disorders in South Korea. In this study, we investigated the protective effects of Myelophil on a whisker removal-induced psycho-emotional stress model. SD rats were subjected to whisker removal after oral administration of Myelophil or ascorbic acid for consecutive 4 days. Whisker removal considerably increased total reactive oxygen species in serum levels as well as cerebral cortex and hippocampal regions in brain tissues. Lipidperoxidation levels were also increased in the cerebral cortex, hippocampus regions, and brain tissue injuries as shown in histopathology and immunohistochemistry. However, Myelophil significantly ameliorated these alterations, and depletion of glutathione contents in both cerebral cortex and hippocampus regions respectively. Serum levels of corticosterone and adrenaline were notably altered after whisker removal stress, whereas these abnormalities were significantly normalized by pre-treatment with Myelophil. The NF-κB was notably activated in both cerebral cortex and hippocampus after whisker removal stress, while it was efficiently blocked by pre-treatment with Myelophil. Myelophil also significantly normalizes alterations of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and interferon-γ in both gene expressions and protein levels. These results suggest that Myelophil has protective effects on brain damages in psycho-emotional stress, and the underlying mechanisms involve regulation of inflammatory proteins, especially NF-κB modulation. PMID:24870587

  11. Perimenopause Amelioration of a TCM Recipe Composed of Radix Astragali, Radix Angelicae Sinensis, and Folium Epimedii: An In Vivo Study on Natural Aging Rat Model

    PubMed Central

    Su, Ji-Yan; Xie, Qing-Feng; Liu, Wei-Jin; Lai, Ping; Liu, Dan-Dan; Tang, Li-Hai; Dong, Tina T. X.; Tsim, Karl W. K.; Lai, Xiao-Ping; Li, Kun-Yin

    2013-01-01

    Traditional Chinese medicine (TCM) has been extensively applied as preferable herbal remedy for menopausal symptoms. In the present work, the potential of a TCM recipe named RRF, composed of Radix Astragali, Radix Angelicae Sinensis, and Folium Epimedii, was investigated on a natural aging rat model. After administration of RRF (141, 282, and 564 mg/kg/d), the circulated estradiol (E2) level increased accompanied by a reduction of serum follicle stimulating hormone (FSH). But no significant impact on serum lutenizing hormone (LH) level was observed. As a result of the E2-FSH-LH adjustment, the histomorphology degenerations of ovary, uterus, and vagina of the 11.5-month female rats were alleviated. And lumbar vertebrae trabecular microstructure was also restored under RRF exposure by means of increasing the trabecular area and area rate. Moreover, levels of hypothalamic dopamine (DA) and norepinephrine (NE) rallied significantly after RRF treatment. Results from our studies suggest that RRF possesses a positive regulation on the estrogen imbalance and neurotransmitter disorder, thereby restoring reproductive organ degeneration and skeleton deterioration. The above-mentioned benefits of RRF on the menopause syndromes recommend RRF as a potential candidate for the treatment of perimenopausal syndrome. PMID:24454513

  12. Screening and isolation of potential lactate dehydrogenase inhibitors from five Chinese medicinal herbs: Soybean, Radix pueraria, Flos pueraria, Rhizoma belamcandae, and Radix astragali.

    PubMed

    Tang, Ying; Li, Senlin; Li, Sainan; Yang, Xiaojing; Qin, Yao; Zhang, Yuchi; Liu, Chunming

    2016-06-01

    Stroke is among the leading causes of death and severe disability worldwide. Flavonoids have been extensively used in the treatment of ischemic stroke by reducing lactate dehydrogenase levels and thereby enhancing blood perfusion to the ischemic region. Here, we used ultrafiltration high-performance liquid chromatography coupled with diode array detection and mass spectrometry for the rapid screening and identification of flavonoids from five Chinese medicinal herbs: soybean, Radix pueraria, Flos pueraria, Rhizoma belamcandae, and Radix astragali. Using PC12 cells as a suitable in vitro model of toxicity, cell viability was quantitated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The results showed that the extracts of soybean and the six major components, namely, acetyldaidzin, malonylgenistin, daidiain, glycitin, genistin, and acetylcitin; the extract of R. pueraria and its main component daidzein; the extract of F. pueraria and its three major components, tectorigenin, tectoridin, and tectorigenin-7-O-xylosylglucosid; and the extract of R. belamcandae and its main component, tectoridin, were strong lactate dehydrogenase inhibitors. Also, the components of R. astragali showed no bioactivity. These findings indicate that the ultrafltration high-performance liquid chromatography coupled with diode array detection and mass spectrometry method could be utilized in rapid screening and separation of bioactive compounds from a complex matrix. PMID:27059876

  13. Discrimination and chemical characterization of different Paeonia lactifloras (Radix Paeoniae Alba and Radix Paeoniae Rubra) by infrared macro-fingerprint analysis-through-separation

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Wang, Ping; Xu, Changhua; Sun, Suqin; Zhou, Qun; Shi, Zhe; Li, Jin; Chen, Tao; Li, Zheng; Cui, Weili

    2015-11-01

    Paeonia lactiflora, a commonly used herbal medicine (HM) in Traditional Chinese Medicine (TCM), mainly has two species, Radix Paeoniae Alba (RPA) and Radix Paeoniae Rubra (RPR), for different clinical applications in TCM. For expounding the chemical profile of RPA and RPR and ensuring the clinical efficacy and safety, an infrared macro-fingerprint analysis-through-separation method integrated with statistical pattern recognition was developed to analyze and discriminate the two Paeonia lactifloras. In IR spectra, the major difference between the two was in the range of 1200-900 cm-1: the strongest peak of RPA was at 1024 cm-1, while that of RPR was 1049 cm-1. The difference was magnified in second derivative spectra. The findings were further verified by investigating the separation process of total glucosides, stepwisely monitored by both of IR and UPLC-MS/MS. Simultaneously, the aqueous extracts of RPA and RPR had been separated continuously to acquire the comprehensively hierarchical chemical characteristics for undoubtedly identification and subsequently discrimination of the two herbs. Moreover, 60 batches of the two HMs (30 for each) were objectively classified by principal component regression (PCR) model based on IR macro-fingerprints.

  14. Preclinical Evidence of Rapid-Onset Antidepressant-Like Effect in Radix Polygalae Extract

    PubMed Central

    Park, Hyunwoo; Kim, Yoorim; Park, Sung Hyun; Swanberg, Kelley; Shin, Joo-Yeon; Ha, Sang-Kyu; Cho, Yoonju; Bang, Soo-Yong; Lew, Jae-Hwan; Cho, Seung-Hun; Maeng, Sungho

    2014-01-01

    Radix Polygalae (the root of Polygala tenuifolia) is a herb widely used in traditional Asian medicine that is thought to exert a variety of neuropsychiatric effects. Radix Polygalae extract can protect against N-methyl D-aspartate (NMDA) neurotoxicity and induce brain-derived neurotrophic factor (BDNF) expression, suggesting modulatory roles at glutamatergic synapses and possible antidepressant action. In accordance with this hypothesis, Radix Polygalae extract demonstrated antidepressant-like effects in 8-week-old male C57Bl/6 mice by decreasing behavioral despair in the forced swim and tail suspension tasks and increasing hedonic-like behavior in the female urine sniffing test 30 minutes after a single oral administration of 0.1 mg/kg. Reduced latency to acquire a food pellet in the novely suppressed feeding paradigm, without change in anxiety-like behaviors suggested a rapid-onset nature of the antidepressant-like effect. In addition, it decreased the number of failed escapes in the learned helplessness paradigm after two oral administrations 24 hours and 30 minutes before the first test. Finally, it reversed anhedonia as measured by saccharin preference in mice exposed to the chronic stress model after two administrations of 0.1 mg/kg, in contrast to the repeated administration generally needed for similar effect by monoamergic antidepressants. Immobility reduction in tail suspension task was blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist NBQX, a pattern previously demonstrated by ketamine and other ketamine-like rapid-onset antidepressants. Also similarly to ketamine, Radix Polygalae appeared to acutely decrease phosphorylation of GluR1 serine-845 in the hippocampus while leaving the phosphorylation of hippocampal mTOR serine 2448 unchanged. These findings serve as preclinical evidence that Radix Polygalae extract exerts rapid-onset antidepressant effects by modulating glutamatergic synapses in critical brain

  15. Preclinical evidence of rapid-onset antidepressant-like effect in Radix Polygalae extract.

    PubMed

    Shin, Im-Joon; Son, Sung Un; Park, Hyunwoo; Kim, Yoorim; Park, Sung Hyun; Swanberg, Kelley; Shin, Joo-Yeon; Ha, Sang-Kyu; Cho, Yoonju; Bang, Soo-Yong; Lew, Jae-Hwan; Cho, Seung-Hun; Maeng, Sungho

    2014-01-01

    Radix Polygalae (the root of Polygala tenuifolia) is a herb widely used in traditional Asian medicine that is thought to exert a variety of neuropsychiatric effects. Radix Polygalae extract can protect against N-methyl D-aspartate (NMDA) neurotoxicity and induce brain-derived neurotrophic factor (BDNF) expression, suggesting modulatory roles at glutamatergic synapses and possible antidepressant action. In accordance with this hypothesis, Radix Polygalae extract demonstrated antidepressant-like effects in 8-week-old male C57Bl/6 mice by decreasing behavioral despair in the forced swim and tail suspension tasks and increasing hedonic-like behavior in the female urine sniffing test 30 minutes after a single oral administration of 0.1 mg/kg. Reduced latency to acquire a food pellet in the novely suppressed feeding paradigm, without change in anxiety-like behaviors suggested a rapid-onset nature of the antidepressant-like effect. In addition, it decreased the number of failed escapes in the learned helplessness paradigm after two oral administrations 24 hours and 30 minutes before the first test. Finally, it reversed anhedonia as measured by saccharin preference in mice exposed to the chronic stress model after two administrations of 0.1 mg/kg, in contrast to the repeated administration generally needed for similar effect by monoamergic antidepressants. Immobility reduction in tail suspension task was blocked by the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist NBQX, a pattern previously demonstrated by ketamine and other ketamine-like rapid-onset antidepressants. Also similarly to ketamine, Radix Polygalae appeared to acutely decrease phosphorylation of GluR1 serine-845 in the hippocampus while leaving the phosphorylation of hippocampal mTOR serine 2448 unchanged. These findings serve as preclinical evidence that Radix Polygalae extract exerts rapid-onset antidepressant effects by modulating glutamatergic synapses in critical brain

  16. Evaluation of soft tissue coverage over porous polymethylmethacrylate space maintainers within nonhealing alveolar bone defects.

    PubMed

    Kretlow, James D; Shi, Meng; Young, Simon; Spicer, Patrick P; Demian, Nagi; Jansen, John A; Wong, Mark E; Kasper, F Kurtis; Mikos, Antonios G

    2010-12-01

    Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time point. For a tissue engineering approach to be employed in the treatment of such injuries, a two-stage approach could potentially be used. The present study describes methods for fabrication, characterization, and processing of porous polymethylmethacrylate (PMMA) space maintainers for temporary retention of space in bony craniofacial defects. Carboxymethylcellulose hydrogels were used as a porogen. Implants with controlled porosity and pore interconnectivity were fabricated by varying the ratio of hydrogel:polymer and the amount of carboxymethylcellulose within the hydrogel. The in vivo tissue response to the implants was observed by implanting solid, low-porosity, and high-porosity implants (n = 6) within a nonhealing rabbit mandibular defect that included an oral mucosal defect to allow open communication between the oral cavity and the mandibular defect. Oral mucosal wound healing was observed after 12 weeks and was complete in 3/6 defects filled with solid PMMA implants and 5/6 defects filled with either a low- or high-porosity PMMA implant. The tissue response around and within the pores of the two formulations of porous implants tested in vivo was characterized, with the low-porosity implants surrounded by a minimal but well-formed fibrous capsule in contrast to the high-porosity implants, which were surrounded and invaded by almost exclusively inflammatory tissue. On the basis of these results, PMMA implants with limited porosity hold promise for temporary implantation and space maintenance within clean/contaminated bone defects. PMID:20524844

  17. Evaluation of Soft Tissue Coverage over Porous Polymethylmethacrylate Space Maintainers Within Nonhealing Alveolar Bone Defects

    PubMed Central

    Kretlow, James D.; Shi, Meng; Young, Simon; Spicer, Patrick P.; Demian, Nagi; Jansen, John A.; Wong, Mark E.; Kasper, F. Kurtis

    2010-01-01

    Current treatment of traumatic craniofacial injuries often involves early free tissue transfer, even if the recipient site is contaminated or lacks soft tissue coverage. There are no current tissue engineering strategies to definitively regenerate tissues in such an environment at an early time point. For a tissue engineering approach to be employed in the treatment of such injuries, a two-stage approach could potentially be used. The present study describes methods for fabrication, characterization, and processing of porous polymethylmethacrylate (PMMA) space maintainers for temporary retention of space in bony craniofacial defects. Carboxymethylcellulose hydrogels were used as a porogen. Implants with controlled porosity and pore interconnectivity were fabricated by varying the ratio of hydrogel:polymer and the amount of carboxymethylcellulose within the hydrogel. The in vivo tissue response to the implants was observed by implanting solid, low-porosity, and high-porosity implants (n = 6) within a nonhealing rabbit mandibular defect that included an oral mucosal defect to allow open communication between the oral cavity and the mandibular defect. Oral mucosal wound healing was observed after 12 weeks and was complete in 3/6 defects filled with solid PMMA implants and 5/6 defects filled with either a low- or high-porosity PMMA implant. The tissue response around and within the pores of the two formulations of porous implants tested in vivo was characterized, with the low-porosity implants surrounded by a minimal but well-formed fibrous capsule in contrast to the high-porosity implants, which were surrounded and invaded by almost exclusively inflammatory tissue. On the basis of these results, PMMA implants with limited porosity hold promise for temporary implantation and space maintenance within clean/contaminated bone defects. PMID:20524844

  18. Human submandibular-sublingual saliva promotes adhesion of Candida albicans to polymethylmethacrylate.

    PubMed Central

    Edgerton, M; Scannapieco, F A; Reddy, M S; Levine, M J

    1993-01-01

    The purpose of this study was to identify components of saliva that interact with Candida albicans in solution and that may modulate adhesion to dental acrylic (polymethylmethacrylate [PMMA]) surfaces. Saliva-derived pellicles extracted from C. albicans blastoconidia and hyphal-form cells mixed with fresh human submandibular-sublingual saliva (HSMSL) contained predominantly high- and low-molecular-weight mucins (MG1 and MG2, respectively). In contrast, few components from fresh human parotid saliva were adsorbed to yeast cells. Coating PMMA beads with HSMSL significantly enhanced (10-fold) adhesion of both growth forms of C. albicans compared with human parotid saliva (2-fold), suggesting a role for mucins in adhesion. HSMSL-enhanced adhesion was completely abolished by preadsorbing HSMSL with either blastoconidia or hyphal-form cells prior to coating PMMA. However, coating PMMA with purified salivary mucins or the addition of mucin to preadsorbed saliva did not enhance or restore adhesion to levels found with fresh HSMSL. Adhesion assays employing guanidine-treated fresh HSMSL showed a complete lack of Candida binding, suggesting that subjecting HSMSL to dissociating conditions may alter a property of salivary mucins crucial for C. albicans adhesion. Protease and glycosidase treatment of yeast cells significantly reduced adhesion to HSMSL-coated PMMA. In addition, preincubation of C. albicans with mannose and galactose inhibited adhesion to HSMSL-coated PMMA. These results suggest that mucins may play a role in C. albicans adhesion to saliva-coated PMMA and that a glycoprotein on the yeast surface may be involved in these events. Images PMID:8500903

  19. Therapeutic potentials of naringin on polymethylmethacrylate induced osteoclastogenesis and osteolysis, in vitro and in vivo assessments

    PubMed Central

    Li, Nianhu; Xu, Zhanwang; Wooley, Paul H; Zhang, Jianxin; Yang, Shang-You

    2014-01-01

    Wear debris associated periprosthetic osteolysis represents a major pathological process associated with the aseptic loosening of joint prostheses. Naringin is a major flavonoid identified in grapefruit. Studies have shown that naringin possesses many pharmacological properties including effects on bone metabolism. The current study evaluated the influence of naringin on wear debris induced osteoclastic bone resorption both in vitro and in vivo. The osteoclast precursor cell line RAW 264.7 was cultured and stimulated with polymethylmethacrylate (PMMA) particles followed by treatment with naringin at several doses. Tartrate resistant acid phosphatase (TRAP), calcium release, and gene expression profiles of TRAP, cathepsin K, and receptor activator of nuclear factor-kappa B were sequentially evaluated. PMMA challenged murine air pouch and the load bearing tibia titanium pin-implantation mouse models were used to evaluate the effects of naringin in controlling PMMA induced bone resorption. Histological analyses and biomechanical pullout tests were performed following the animal experimentation. The in vitro data clearly demonstrated the inhibitory effects of naringin in PMMA induced osteoclastogenesis. The naringin dose of 10 μg/mL exhibited the most significant influence on the suppression of TRAP activities. Naringin treatment also markedly decreased calcium release in the stimulated cell culture medium. The short-term air pouch mouse study revealed that local injection of naringin ameliorated the PMMA induced inflammatory tissue response and subsequent bone resorption. The long-term tibia pin-implantation mouse model study suggested that daily oral gavage of naringin at 300 mg/kg dosage for 30 days significantly alleviated the periprosthetic bone resorption. A significant increase of periprosthetic bone volume and regaining of the pin stability were found in naringin treated mice. Overall, this study suggests that naringin may serve as a potential therapeutic

  20. Copper vapor laser machining of polyimide and polymethylmethacrylate in atmospheric pressure air

    NASA Astrophysics Data System (ADS)

    Ventzek, P. L. G.; Gilgenbach, R. M.; Ching, C. H.; Lindley, R. A.; McColl, W. B.

    1992-10-01

    A repetitively pulsed copper vapor laser (510 and 578 nm) is used to machine an opaque polymer (polyimide-Vespel) and a transparent polymer (polymethylmethacrylate-Lucite). Lucite is machinable by coating the surface with an ink which is semi-opaque to the green and yellow laser light. The repetition rate of the laser was 10 kHz with approximately 0.35 mJ/pulse and 3.5 W average power at the copper vapor laser wavelengths for a pulse width of 40 ns. The copper vapor laser thermally loads the target, generating thermal waves and sound waves in the gas which are investigated using HeNe laser beam deflection. The gas adjacent to the target is heated to steady state on the order of 100-400 s. Above the etching threshold, at approximately 10 mJ/cm2/pulse, the target is rapidly machined: 2-mm-diam, 2-mm-deep holes are drilled in 300 s in Vespel. At higher fluences of 100-150 mJ/cm2/pulse in 760 Torr of air it takes 180 s to bore through a 2-mm-thick disk of Vespel. The machined surfaces of the two polymers are very different. Machined Vespel samples are charred and cratered, whereas the Lucite samples show evidence of melting with little charring. The machining of polymers by visible-light copper vapor lasers is being compared to UV photoablation by KrF excimer laser light in order to study thermal versus nonthermal etching mechanisms.

  1. Antibiotic-releasing Porous Polymethylmethacrylate Constructs for Osseous Space Maintenance and Infection Control

    PubMed Central

    Shi, Meng; Kretlow, James D.; Nguyen, Anson; Young, Simon; Baggett, L. Scott; Wong, Mark E.; Kasper, F. Kurtis; Mikos, Antonios G.

    2010-01-01

    The use of a strategy involving space maintenance as the initial step of a two-stage regenerative medicine approach toward reconstructing significant bony or composite tissue defects in the craniofacial area, preserves the void volume of bony defects and could promote soft tissue healing prior to the subsequent definitive repair. One of the complications with a biomaterial-based space maintenance approach is local infection, which requires early, effective eradication, ideally through local antibiotic delivery. The purpose of this study is to develop a dual function implant material for maintaining osseous space and releasing an antibiotic to eliminate local infection in bony defects. Colistin, a polymyxin antibiotic, was chosen specifically to address infections with Acinetobacter species, the most common pathogen associated with combat-related traumatic craniofacial injuries. Porous polymethylmethacrylate (PMMA) constructs incorporating poly(lactic-co-glycolic acid) (PLGA) microspheres were fabricated by mixing a clinically used bone cement formulation of PMMA powder and methylmethacrylate liquid with a carboxymethylcellulose (CMC) hydrogel (40 or 50 wt%) to impart porosity and PLGA microspheres (10 or 15 wt%) loaded with colistin to control drug release. The PMMA/CMC/PLGA construct featured mild setting temperature, controllable surface/bulk porosity by incorporation of the CMC hydrogel, reasonably strong compressive properties, and continuous drug release over a period of 5 weeks with total drug release of 68.1-88.3%, depending on the weight percentage of CMC and PLGA incorporation. The concentration of released colistin was well above its reported minimum inhibitory concentration against susceptible species for 5 weeks. This study provides information on the composition parameters that enable viable porosity characteristics/drug release kinetics of the PMMA/CMC/PLGA construct for the initial space maintenance as part of a two-stage regenerative medicine

  2. Solid state neutron dosimeter for space applications

    NASA Technical Reports Server (NTRS)

    Entine, Gerald; Nagargar, Vivek; Sharif, Daud

    1990-01-01

    Personnel engaged in space flight are exposed to significant flux of high energy neutrons arising from both primary and secondary sources of ionizing radiation. Presently, there exist no compact neutron sensor capable of being integrated in a flight instrument to provide real time measurement of this radiation flux. A proposal was made to construct such an instrument using special PIN silicon diode which has the property of being insensitive to the other forms of ionizing radiation. Studies were performed to determine the design and construction of a better reading system to allow the PIN diode to be read with high precision. The physics of the device was studied, especially with respect to those factors which affect the sensitivity and reproducibility of the neutron response. This information was then used to develop methods to achieve high sensitivity at low neutron doses. The feasibility was shown of enhancing the PIN diode sensitivity to make possible the measurement of the low doses of neutrons encountered in space flights. The new PIN diode will make possible the development of a very compact, accurate, personal neutron dosimeter.

  3. PDT dose dosimeter for pleural photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Kim, Michele M.; Darafsheh, Arash; Ahmad, Mahmoud; Finlay, Jarod C.; Zhu, Timothy C.

    2016-03-01

    PDT dose is the product of the photosensitizer concentration and the light fluence in the target tissue. For improved dosimetry during plural photodynamic therapy (PDT), a PDT dose dosimeter was developed to measure both the light fluence and the photosensitizer concentration simultaneously in the same treatment location. Light fluence and spectral data were rigorously compared to other methods of measurement (e.g. photodiode, multi-fiber spectroscopy contact probe) to assess the accuracy of the measurements as well as their uncertainty. Photosensitizer concentration was obtained by measuring the fluorescence of the sensitizer excited by the treatment light. Fluence rate based on the intensity of the laser spectrum was compared to the data obtained by direct measurement of fluence rate by a fiber-coupled photodiode. Phantom studies were done to obtain an optical property correction for the fluorescence signal. Measurements were performed in patients treated Photofrin for different locations in the pleural cavity. Multiple sites were measured to investigate the heterogeneity of the cavity and to provide cross-validation via relative dosimetry. This novel method will allow for accurate real-time determination of delivered PDT dose and improved PDT dosimetry.

  4. Preliminary evaluation of implantable MOSFET radiation dosimeters.

    PubMed

    Beddar, A S; Salehpour, M; Briere, T M; Hamidian, H; Gillin, M T

    2005-01-01

    In this paper, we report on measurements performed on a new prototype implantable radiation detector that uses metal-oxide semiconductor field effect transistors (MOSFETs) designed for in vivo dosimetry. The dosimeters, which are encapsulated in hermetically sealed glass cylinders, are used in an unbiased mode during irradiation, unlike other MOSFET detectors previously used in radiotherapy applications. They are powered by radio frequency telemetry for dose measurements, obviating the need for a power supply within each capsule. We have studied the dosimetric characteristics of these MOSFET detectors in vitro under irradiation from a 60Co source. The detectors show a dose reproducibility generally within 5% or better, with the main sources of error being temperature fluctuations occurring between the pre- and post-irradiation measurements as well as detector orientation. A better temperature-controlled environment leads to a reproducibility within 2%. Our preliminary in vitro results show clearly that true non-invasive in vivo dosimetry measurements are feasible and can be performed remotely using telemetric technology. PMID:15715428

  5. PDT Dose Dosimeter for Pleural Photodynamic Therapy

    PubMed Central

    Kim, Michele M.; Darafsheh, Arash; Ahmad, Mahmoud; Finlay, Jarod C.; Zhu, Timothy C.

    2016-01-01

    PDT dose is the product of the photosensitizer concentration and the light fluence in the target tissue. For improved dosimetry during plural photodynamic therapy (PDT), a PDT dose dosimeter was developed to measure both the light fluence and the photosensitizer concentration simultaneously in the same treatment location. Light fluence and spectral data were rigorously compared to other methods of measurement (e.g. photodiode, multi-fiber spectroscopy contact probe) to assess the accuracy of the measurements as well as their uncertainty. Photosensitizer concentration was obtained by measuring the fluorescence of the sensitizer excited by the treatment light. Fluence rate based on the intensity of the laser spectrum was compared to the data obtained by direct measurement of fluence rate by a fiber-coupled photodiode. Phantom studies were done to obtain an optical property correction for the fluorescence signal. Measurements were performed in patients treated Photofrin for different locations in the pleural cavity. Multiple sites were measured to investigate the heterogeneity of the cavity and to provide cross-validation via relative dosimetry. This novel method will allow for accurate real-time determination of delivered PDT dose and improved PDT dosimetry. PMID:27053825

  6. Worms in space? A model biological dosimeter.

    PubMed

    Zhao, Yang; Johnsen, Robert; Baillie, David; Rose, Ann

    2005-06-01

    Although it is well known that radiation causes mutational damage, little is known about the biological effects of long-term exposure to radiation in space. Exposure to radiation can result in serious heritable defects in experimental animals, and in humans, susceptibility to cancer, radiation-sickness, and death at high dosages. It is possible to do ground controlled studies of different types of radiation on experimental animals and to physically measure radiation on the space station or on space probes. However, the actual biological affects of long-term exposure to the full range of space radiation have not been studied, and little information is available about the biological consequences of solar flares. Biological systems are not simply passive recording instruments. They respond differently under different conditions, and thus it is important to be able to collect data from a living animal. There are technical difficulties that restrict the placement of an experimental organism in a space environment for long periods of time, in a manner that allows for the recovery of genetic data. Use of the self-fertilizing hermaphroditic nematode, Caenorhabditis elegans offers potential for the design of a biological dosimeter. In this paper, we describe the advantages of this model system and review the literature of C. elegans in space. PMID:16038089

  7. Solid state neutron dosimeter for space applications

    NASA Astrophysics Data System (ADS)

    Entine, Gerald; Nagargar, Vivek; Sharif, Daud

    1990-08-01

    Personnel engaged in space flight are exposed to significant flux of high energy neutrons arising from both primary and secondary sources of ionizing radiation. Presently, there exist no compact neutron sensor capable of being integrated in a flight instrument to provide real time measurement of this radiation flux. A proposal was made to construct such an instrument using special PIN silicon diode which has the property of being insensitive to the other forms of ionizing radiation. Studies were performed to determine the design and construction of a better reading system to allow the PIN diode to be read with high precision. The physics of the device was studied, especially with respect to those factors which affect the sensitivity and reproducibility of the neutron response. This information was then used to develop methods to achieve high sensitivity at low neutron doses. The feasibility was shown of enhancing the PIN diode sensitivity to make possible the measurement of the low doses of neutrons encountered in space flights. The new PIN diode will make possible the development of a very compact, accurate, personal neutron dosimeter.

  8. Quality Evaluation of Scrophulariae Radix Processed by Different 'Sweating' Methods Based on Simultaneous Determination of Multiple Bioactive Constituents Combined with Grey Relational Analysis.

    PubMed

    Wang, Shengnan; Hua, Yujiao; Xu, Li; Zou, Lisi; Liu, Xunhong; Luo, Yiyuan; Liu, Juanxiu; Yan, Ying

    2016-01-01

    Scrophulariae Radix is one of the most popular traditional Chinese medicines (TCMs), which needs to be processed by 'sweating' methods. Primary processing of Scrophulariae Radix is an important link which closely relates to the quality of products in this TCM. To facilitate selection of the suitable 'sweating' processing method for Scrophulariae Radix, in this study the quality of Scrophulariae Radix processed by different 'sweating' methods was evaluated based on simultaneous determination of multiple bioactive constituents combined with grey relational analysis. The contents of iridoid glycosides, phenylpropanoid glycosides, and organic acids in Scrophulariae Radix processed by different 'sweating' methods were simultaneously determined using ultra high performance liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry (UPLC-QTRAP-MS/MS). Furthermore, grey relational analysis (GRA) was performed to evaluate the 'sweating' processed samples according to the contents of twelve constituents. All of the results demonstrated that the quality of Scrophulariae Radix processed by oven drying at 35 °C and 'sweating' for three days was better. The developed method was useful for the overall assessment on quality of Scrophulariae Radix, and this study may provide the foundation and support for 'sweating' processing of Scrophulariae Radix in normalization and standardization. PMID:27367656

  9. Chromatographic fingerprint combined with content of asperosaponin VI and antioxidant activity for quality evaluation of wine-fried Dipsaci Radix.

    PubMed

    Song, Li; Wang, Shaoyun; Duan, Xiaoju; Liu, Xinhua; Li, Zhaofang; Nie, Lei; Chu, Guangyi

    2014-06-01

    Dipsaci Radix, the dry root of Dipsacusasper Wall. ex Henry, is a commonly used traditional Chinese medicine (TCM). A novel comprehensive method was proposed for quality evaluation of wine-fried Dipsaci Radix by an integrated data including three aspects of information: high performance liquid chromatography (HPLC) fingerprint, asperosaponin VI content and antioxidant activity (AA). Various indicators including fingerprint similarity, asperosaponin VI content and AA were respectively employed for quality assessment of processed Dipsaci Radix samples. Results showed that considerable differences existed in quality of processed samples with different processing conditions according to three indicators. Among the factors affecting quality of wine-fried Dipsaci Radix, heating temperature was the most influential factor based on analysis of variance (ANOVA), and should be cautiously controlled. The three evaluation indicators respectively used for optimization of processing technology suggested different optimal conditions of wine-frying. Therefore, a combined indicator based on three evaluation indicators was used for determination of optimal processing condition. Multivariate statistical methods such as Hierarchical Clustering Analysis (HCA) and Principal Components Analysis (PCA) were both employed to classify the processed samples for quality evaluation. To more comprehensively evaluate the quality of wine-fried Dipsaci Radix, HPLC fingerprint combined with content of asperosaponin VI and AA may be a reasonable and practical approach. PMID:25115076

  10. The Protective Effect of Radix Polygoni Multiflori on Diabetic Encephalopathy via Regulating Myosin Light Chain Kinase Expression

    PubMed Central

    He, Yu; Wang, Feng; Chen, Shiqiang; Liu, Mi; Pan, Wei; Li, Xing

    2015-01-01

    Currently there has been no effective treatment of diabetic encephalopathy. Radix Polygoni Multiflori, a famous traditional Chinese medicine, is widely used in antiaging treatment, especially in prevention and treatment of Alzheimer's diseases. In this study we tried to explore the effect of Radix Polygoni Multiflori on cognitive function among diabetic rats with demonstrated cognitive impairment. SD rats were divided into group A (control group), group B (diabetes), group C (treated with Radix Polygoni Multiflori at the dose of 2 g/kg/d), and group D (treated with same drug at the dose of 1 g/kg/d). The results showed that 8 weeks of Radix Polygoni Multiflori treatment could improve the cognitive dysfunction of diabetic rats (P < 0.01), recover the ultrastructure of hippocampal neurons, and increase the number of synapses in a dose-dependent manner. Further experiment also suggested that the neuroprotective effect of Radix Polygoni Multiflori was partly achieved by downregulating MLCK expression in hippocampus via ERK signaling. PMID:26199947

  11. Radix dolgini: The integrative taxonomic approach supports the species status of a Siberian endemic snail (Mollusca, Gastropoda, Lymnaeidae).

    PubMed

    Vinarski, Maxim V; Aksenova, Olga V; Bespalaya, Yulia V; Bolotov, Ivan N; Schniebs, Katrin; Gofarov, Mikhail Yu; Kondakov, Alexander V

    2016-01-01

    The molecular techniques are the standard tool for the study of the taxonomic position and phylogenetic affinities of the lymnaeid genus Radix Montfort, 1810, and the majority of the European representatives of this taxon have been studied in this respect. However, a plethora of nominal species of Radix described from Northern Asia (Siberia and the Russian Far East) are still characterized only morphologically, raising some doubts concerning their validity. In this paper, we present the triple (morphological, molecular, and zoogeographical) evidence that there is at least one endemic species of Radix, Radix dolgini (Gundrizer and Starobogatov, 1979), widely distributed in Siberia and Western Mongolia. Phylogenetically, it is a sister species to the European R. labiata (Rossmaessler, 1835) [=R. peregra auct.], and their common ancestor most probably lived in the Pliocene, nearly 3.25Myr ago. Our results assume the existence of an extended dispersal barrier for freshwater hydrobionts between Europe and Siberia in the Late Pliocene that may be important for biogeographical explanations. Three other nominal Siberian species of Radix: R. kurejkae (Gundrizer and Starobogatov, 1979), R. gundrizeri (Kruglov and Starobogatov, 1983), and R. ulaganica (Kruglov and Starobogatov, 1983) proved to be the junior synonyms of R. dolgini. PMID:26705968

  12. [Analysis of aconite alkaloids in the combination of radix aconiti lateralis preparata with different herbs by ESI-MS spectrometry].

    PubMed

    Yue, Hao; Pi, Zi-feng; Song, Feng-rui; Liu, Zhi-qiang; Liu, Shu-ying

    2007-02-01

    The method was established study the influence of different herbal combination with Radix Aconiti in the traditional medical formulae on content of the aconite alkaloids, for elucidating the scientific basis of reducing the toxicity of aconite in traditional Chinese medical formulation. The samples for ESI-MS study were prepared by decocting a mixture of Radix Aconiti Lateralis Preparata ( RALP) with Radix Glycyrrhizae Preparata (RGP) , Radix Paeoniae Alba ( RPA) , Rhizoma Zingiberis (RZ) or Radix Et Rhizoma Rhei ( RERR) , separately, and extracting the residue of the above mentioned mixtures after decocting. The diester-diterpenoid alkaloids (DDAs) was lower in the herb couples of RALP-RGP, RALP-RPA, RALP-RZ and RALP-RERR, and lipo-alkaloids was increased in the herb couples of RALP-RGP, RALP-RPA and RALP-RZ. The reason of reducing toxic effect principle is that the components of RGP, RPA and RZ have ester-exchange reactions with DDAs in RALP to produce lipo-alkaloids of low toxicity in the decocting process of the herb couples. The combination of RALP-RERR can reduce the content of DDAs in decoction and residue due to the formation of water insoluble alkaloid compound. PMID:17518052

  13. Long-Term Consumption of Platycodi Radix Ameliorates Obesity and Insulin Resistance via the Activation of AMPK Pathways.

    PubMed

    Lee, Chae Eun; Hur, Haeng Jeon; Hwang, Jin-Taek; Sung, Mi Jeong; Yang, Hye Jeong; Kim, Hyun-Jin; Park, Jae Ho; Kwon, Dae Young; Kim, Myung-Sunny

    2012-01-01

    This study was designed to evaluate the effects and mechanism of Platycodi radix, having white balloon flower (Platycodon grandiflorum for. albiflorum (Honda) H. Hara) on obesity and insulin resistance. The extracts of Platycodi radix with white balloon flower were tested in cultured cells and administered into mice on a high-fat diet. The Platycodi radix activated the AMPK/ACC phosphorylation in C2C12 myotubes and also suppressed adipocyte differentiation in 3T3-L1 cells. In experimental animal, it suppressed the weight gain of obese mice and ameliorated obesity-induced insulin resistance. It also reduced the elevated circulating mediators, including triglyceride (TG), T-CHO, leptin, resistin, and monocyte chemotactic protein (MCP)-1 in obesity. As shown in C2C12 myotubes, the administration of Platycodi radix extracts also recovered the AMPK/ACC phosphorylation in the muscle of obese mice. These results suggest that Platycodi radix with white balloon flower ameliorates obesity and insulin resistance in obese mice via the activation of AMPK/ACC pathways and reductions of adipocyte differentiation. PMID:22829857

  14. Angular dependence of mammographic dosimeters in digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Bradley, Lena R.; Carton, Ann-Katherine; Maidment, Andrew D. A.

    2010-04-01

    Digital Breast Tomosynthesis (DBT) is an emerging imaging modality that combines tomography with conventional digital mammography. In developing DBT dosimetry, a direct application of mammographic dosimetry has appeal. However, DBT introduces rotation of the x-ray tube relative to the dosimeter, thus raising questions about the angular dependence of mammographic dosimeters. To measure this dependence, two ionization chambers, two solid-stated detectors, and one photodiode were rotated relative to an incident Mo/Mo x-ray beam. In this isocentric DBT simulation, the signal of each dosimeter was studied over an angular range of 180° for tube voltages of 26 to 34 kV. One ionization chamber was then modeled numerically to study the response to various monoenergetic beams. The results show that all dosimeters underestimate dose to varying degrees; solid-state detectors show the greatest angular dependence while ionization chambers show the least. Correction factors were computed from the data for isocentric DBT images using projection angles up to +/-25° these factors ranged from 1.0014 to 1.1380. The magnitude of the angular dependence generally decreased with increasing energy, as shown with both the measured and modeled data. As a result, the error arising in measuring DBT dose with a mammographic dosimeter varies significantly; it cannot always be disregarded. The use of correction factors may be possible but is largely impractical, as they are specific to the dosimeter, x-ray beam, and DBT geometry. Instead, an angle-independent dosimeter may be more suitable for DBT.

  15. Description and evaluation of the Hanford personnel dosimeter program from 1944 through 1989. [Contain Glossary

    SciTech Connect

    Wilson, R.H.; Fix, J.J.; Baumgartner, W.V.; Nichols, L.L.

    1990-09-01

    This report describes the evolution of personnel dosimeter technology at Hanford since the inception of Hanford operations in 1944. Each of the personnel dosimeter systems used by people working or visiting Hanford is described. In addition, the procedures used to calibrate and calculate dose for each of the dosimeter systems are described. The accuracy of the recorded dose, primarily whole body deep dose, for the different dosimeter systems is evaluated. The evaluation is based on an extensive review of historical literature, as well as a 1989 intercomparison study of all film dosimeters and performance testing of the thermoluminescent dosimeter, also conducted during 1989. 73 refs., 40 figs., 41 tabs.

  16. Comparative Evaluation of Sorption, Solubility and Microhardness of Heat Cure Polymethylmethacrylate Denture Base Resin & Flexible Denture Base Resin

    PubMed Central

    Bulbule, Nilesh; Kulkarni, Shilpa; Shah, Riddhi; Kakade, Dilip

    2014-01-01

    Aim: The aim of the study was to evaluate and compare sorption, solubility and microhardness of heat cure polymethylmethacrylate (PMMA) denture base resin and flexible (thermoplastic polyamide nylon) denture base resin. Materials and Methods: Sorption, solubility and microhardness were assessed to determine compliance with ADA Specification no. 12. Results were assessed using statistical and observational analyses. Result: All materials satisfied ADA requirements for sorption, solubility and microhardness. Heat cure PMMA showed more sorption, solubility and microhardness than flexible (thermoplastic polyamide nylon). Conclusion: Flexible (thermoplastic polyamide nylon) resin absorbs less water, is less soluble and is more flexible than PMMA. PMID:25302291

  17. A study on the effect of ethanol extract of Radix rhapontici on erythrocyte immune function in rats.

    PubMed

    Yan, Xiang; Zhao, Hong; Guan, Yin; Song, Yanbin; Meng, Jing

    2013-01-01

    This paper mainly studied the effect of ethanol extract of Radix rhapontici on erythrocyte immune function in SD rats with acute blood stasis. The methods used the effect on erythrocyte immune function. After intragastric administration of suspension of ethanol extract of Radix rhapontici to SD rats for 3 weeks, on the 21st day from intragastric administration, SD rats were made into blood stasis model and bloods were collected to determine the C3b, C3bRR, RFIR, and RFER in erythrocyte immune function. Meanwhile, serum total antioxidant activity (TAA), superoxide dismutase (SOD) activity, and serum malondialdehyde (MDA) level of rats were determined, and experimental results were analysed with analysis of variance and Q test. The results showed that the ethanol extract of Radix rhapontici had a very good effect on enhancement of erythrocyte immune function in SD rats. PMID:24311883

  18. Site-specific calibration of the Hanford personnel neutron dosimeter

    SciTech Connect

    Endres, A.W.; Brackenbush, L.W.; Baumgartner, W.V.; Rathbone, B.A.

    1994-10-01

    A new personnel dosimetry system, employing a standard Hanford thermoluminescent dosimeter (TLD) and a combination dosimeter with both CR-39 nuclear track and TLD-albedo elements, is being implemented at Hanford. Measurements were made in workplace environments in order to verify the accuracy of the system and establish site-specific factors to account for the differences in dosimeter response between the workplace and calibration laboratory. Neutron measurements were performed using sources at Hanford`s Plutonium Finishing Plant under high-scatter conditions to calibrate the new neutron dosimeter design to site-specific neutron spectra. The dosimeter was also calibrated using bare and moderated {sup 252}Cf sources under low-scatter conditions available in the Hanford Calibration Laboratory. Dose equivalent rates in the workplace were calculated from spectrometer measurements using tissue equivalent proportional counter (TEPC) and multisphere spectrometers. The accuracy of the spectrometers was verified by measurements on neutron sources with calibrations directly traceable to the National Institute of Standards and Technology (NIST).

  19. PNNL Results from 2010 CALIBAN Criticality Accident Dosimeter Intercomparison Exercise

    SciTech Connect

    Hill, Robin L.; Conrady, Matthew M.

    2011-10-28

    This document reports the results of the Hanford personnel nuclear accident dosimeter (PNAD) and fixed nuclear accident dosimeter (FNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on September 20-23, 2010. Pacific Northwest National Laboratory (PNNL) participated in a criticality accident dosimeter intercomparison exercise at the Commissariat a Energie Atomique (CEA) Valduc Center near Dijon, France on September 20-23, 2010. The intercomparison exercise was funded by the U.S. Department of Energy, Nuclear Criticality Safety Program, with Lawrence Livermore National Laboratory as the lead Laboratory. PNNL was one of six invited DOE Laboratory participants. The other participating Laboratories were: Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Savannah River Site (SRS), the Y-12 National Security Complex at Oak Ridge, and Sandia National Laboratory (SNL). The goals of PNNL's participation in the intercomparison exercise were to test and validate the procedures and algorithm currently used for the Hanford personnel nuclear accident dosimeters (PNADs) on the metallic reactor, CALIBAN, to test exposures to PNADs from the side and from behind a phantom, and to test PNADs that were taken from a historical batch of Hanford PNADs that had varying degrees of degradation of the bare indium foil. Similar testing of the PNADs was done on the Valduc SILENE test reactor in 2009 (Hill and Conrady, 2010). The CALIBAN results are reported here.

  20. Dose rate dependency of micelle leucodye 3D gel dosimeters

    NASA Astrophysics Data System (ADS)

    Vandecasteele, J.; Ghysel, S.; De Deene, Y.

    2010-11-01

    Recently a novel 3D radiochromic gel dosimeter was introduced which uses micelles to dissolve a leucodye in a gelatin matrix. Experimental results show that this 3D micelle gel dosimeter was found to be dose rate dependent. A maximum difference in optical dose sensitivity of 70% was found for dose rates between 50 cGy min-1 and 400 cGy min-1. A novel composition of 3D radiochromic dosimeter is proposed composed of gelatin, sodium dodecyl sulphate, chloroform, trichloroacetic acid and leucomalachite green. The novel gel dosimeter formulation exhibits comparable radio-physical properties in respect to the composition previously proposed. Nevertheless, the novel formulation was found to be still dose rate dependent. A maximum difference of 33% was found for dose rates between 50 cGy min-1 and 400 cGy min-1. On the basis of these experimental results it is concluded that the leucodye micelle gel dosimeter is still unsatisfactory for clinical radiation therapy dose verifications. Some insights in the physico-chemical mechanisms were obtained and are discussed.

  1. Combined effects of fangchinoline from Stephania tetrandra Radix and formononetin and calycosin from Astragalus membranaceus Radix on hyperglycemia and hypoinsulinemia in streptozotocin-diabetic mice.

    PubMed

    Ma, Wenjie; Nomura, Masaaki; Takahashi-Nishioka, Tatsuo; Kobayashi, Shinjiro

    2007-11-01

    The anti-hyperglycemic action of Stephania tetrandra Radix (Stephania) is potentiated by Astragalus membranaceus BUNGE Radix (Astragali) in streptozotocin (STZ)-diabetic ddY mice (Tsutsumi et al., Biol. Pharm. Bull., 26, 313 (2003)). Fangchinoline (0.3-3 mg/kg), a main constituent of Stephania, decreased the high level of blood glucose and increased the low level of blood insulin in STZ-diabetic mice. Here, we investigated the combined effects of fangchinoline with isoflavone or isoflavonoid components (formononetin, calycosin and ononin) of Astragali on the hyperglycemia and hypoinsulinemia of STZ-diabetic mice. Formononetin, calycosin and ononin (0.03-0.1 mg/kg) alone did not affect the blood glucose or blood insulin level of the diabetic mice. Formononetin and calycosin (0.03-0.1 mg/kg) potentiated the anti-hyperglycemic action of fangchinoline (0.3 mg/kg), but ononin did not. Formononetin (0.1 mg/kg) facilitated the fangchinoline-induced insulin release, and calycosin (0.1 mg/kg) also facilitated it, though without statistical significance. In conclusion, the combined effect of fangchinoline with formononetin and calycosin on hyperglycemia in the diabetic mice accounted well for the therapeutic effect of the combination of Stephania with Astragali in Boi-ogi-to. The anti-hyperglycemic action of formononetin appeared to be due to its potentiating action on insulin release. Our strategy for studying combinations of crude drugs and their components in Kampo medicine has uncovered new potentiating effects of formononetin and calycosin on the anti-hyperglycemic action of fangchinoline in STZ-diabetic mice. PMID:17978479

  2. US progress on the development of CR-39 based neutron dosimeters

    SciTech Connect

    Hadlock, D.E.

    1987-06-01

    Historically at US nuclear facilities, two types of personnel neutron dosimeters have been in routine use: nuclear track emulsion-Type A (NTA) film and thermoluminescent dosimeter (TLD)-albedo. Both of these dosimeters have energy-dependent responses. Therefore, the neutron energy spectra must be known, to interpret the dosimeter results properly. A new state-of-the-art dosimetry system has been developed within the US Department of Energy (US DOE) Personnel Neutron Dosimeter Evaluation and Upgrade Program. This system is called the combination thermoluminescent dosimeter/track etch dosimeter (TLD/TED). This paper briefly describes US DOE research currently being conducted to further enhance the TED portion of the combination TLD/TED system. The research areas involved include dose sensitivity, neutron energy range, specialized radiators, self-developing dosimeters, and neutron spectrometry. 1 fig., 1 tab.

  3. Pharmacokinetics, intestinal absorption and microbial metabolism of single platycodin D in comparison to Platycodi radix extract

    PubMed Central

    Shan, Jinjun; Zou, Jiashuang; Xie, Tong; Kang, An; Zhou, Wei; Deng, Haishan; Mao, Yancao; Di, Liuqing; Wang, Shouchuan

    2015-01-01

    Background: Platycodi radix, the dried root of Platycodon grandiflorum A. DC, has been widely used as food and herb medicine for treating cough, cold and other respiratory ailments, and platycodin D (PD) is one of the most important compounds in Platycodi Radix. Objective: The purpose of this study was to compare the pharmacokinetic characteristics, intestinal absorption and microbial metabolism of PD in monomer with that in Platycodi radix extract (PRE). Materials and Methods: In the pharmacokinetic study, the concentrations of PD in rat plasma were determined by ultra-performance liquid chromatography-tandem mass spectrometry and the main pharmacokinetic parameters were calculated by data analysis software (DAS). Besides, in vitro Caco-2 cells and fecal lysate were performed to investigate the intestinal absorption and metabolism, respectively. Results: The results from pharmacokinetics showed that the area under the curve, the peak concentration the time to reach peak concentration and mean residence time of PD in PRE were enhanced significantly compared with that in single PD. Caco-2 cells transport study indicated that the absorption of PD both in monomer and in PRE were poor owning that the permeability of PD were <1/106 cm/s. The hydrolysis degree of PD in PRE was significantly lower than that in monomer PD in fecal lysate, which might be illustrated by the other ingredients in PRE influenced the hydrolysis of PD via gut microbiota. Conclusion: These findings indicated that the difference of microbial metabolism, not apparent absorption in intestine for PD between in monomer and in PRE contributed to their pharmacokinetic difference. PMID:26600720

  4. Performance testing of extremity dosimeters against a draft standard

    SciTech Connect

    Harty, R.; Reece, W.D.; Hooker, C.D.; McDonald, J.C.

    1990-09-01

    The assurance of worker radiation safety is directly related to the performance of personnel dosimetry. The US Department of Energy (DOE) has long recognized this critical relationship and has addressed this issue by instituting the DOE Laboratory Accreditation Program (DOELAP) which strives to improve the quality of personnel dosimetry through performance testing, dosimetry calibration, intercomparisons, evaluations and accreditations. One area of personnel dosimetry that has not been specifically addressed by DOELAP is extremity dosimeter testing. This task was directed at assessing the problems of implementing extremity dosimeter performance testing. A series of performance tests were made based on a draft standard written by the Health Physics Society Standards Committee (HPSSC) using extremity dosimeters currently in use at DOE and DOE contractor facilities. The results of this study indicate the need to incorporate performance testing of extremity dosimetry systems into DOELAP. Based on the results of this study, recommendations are made for improvements to the draft standard. 20 refs., 6 figs., 3 tabs.

  5. Commissioning and implementation of an implantable dosimeter for radiation therapy.

    PubMed

    Buzurovic, Ivan; Showalter, Timothy N; Studenski, Matthew T; Den, Robert B; Dicker, Adam P; Cao, Junsheng; Xiao, Ying; Yu, Yan; Harrison, Amy

    2013-01-01

    In this article we describe commissioning and implementation procedures for the Dose Verification System (DVS) with permanently implanted in vivo wireless, telemetric radiation dosimeters for absolute dose measurements. The dosimeter uses a semiconductor device called a metal-oxide semiconductor field-effect transistor (MOSFET) to measure radiation dose. A MOSFET is a transistor that is generally used for amplifying or switching electronic signals. The implantable dosimeter was implemented with the goal of verifying the dose delivered to radiation therapy patients. For the purpose of acceptance testing, commissioning, and clinical implementation and to evaluate characteristics of the dosimeter, the following tests were performed: 1) temperature dependence, 2) reproducibility,3) field size dependence, 4) postirradiation signal drift, 5) dependence on average dose rate, 6) linearity test, 7) angular dependence (different gantry angle position), 8) angular dependence (different DVS angle position), 9) dose rate dependence,10) irradiation depth dependence, 11) effect of cone-beam exposure to the dosimeter, and 12) multiple reading effect. The dosimeter is not currently calibrated for use in the kV range; nonetheless, the effect of the cone-beam procedure on the MOSFET dosimeter was investigated. Phantom studies were performed in both air and water using an Elekta Synergy S Beam-Modulator linear accelerator. Commissioning and clinical implementation for prostate cancer patients receiving external-beam radiation therapy were performed in compliance with the general recommendations given for in vivo dosimetry devices. The reproducibility test in water at human body temperature (37°C) showed a 1.4% absolute difference, with a standard deviation of 5.72 cGy (i.e., SD = 2.9%). The constancy test shows that the average readings at room temperature were 3% lower compared to the readings at human body temperature, with a SD = 2%. Measurements were not dependent upon field size

  6. Photon and neutron kerma coefficients for polymer gel dosimeters

    NASA Astrophysics Data System (ADS)

    El-Khayatt, A. M.; Vega-Carrillo, Hector Rene

    2015-08-01

    Neutron and gamma ray kerma coefficients were calculated for 17 3D dosimeters, for the neutron and gamma ray energy ranges extend from 2.53×10-8 to 29 MeV and from 1.0×10-3 to 20 MeV, respectively. The calculated kermas given here for discrete energies and the kerma coefficients are referred to as "point-wise data". Curves of gamma ray kermas showed slight dips at about 60 keV for most 3D dosimeters. Also, a noticeable departure between thermal and epithermal neutrons kerma sets for water and polymers has been observed. Finally, the obtained results could be useful for dose estimation in the studied 3D dosimeters.

  7. Evaluation of fluorescence in situ hybridization to detect encapsulated Bacillus pumilus SAFR-032 spores released from poly(methylmethacrylate).

    PubMed

    Mohapatra, Bidyut R; La Duc, Myron T

    2012-01-01

    Bacillus pumilus SAFR-032 spores originally isolated from the Jet Propulsion Laboratory spacecraft assembly facility clean room are extremely resistant to UV radiation, H(2)O(2), desiccation, chemical disinfection and starvation compared to spores of other Bacillus species. The resistance of B. pumilus SAFR-032 spores to standard industrial clean room sterilization practices is not only a major concern for medical, pharmaceutical and food industries, but also a threat to the extraterrestrial environment during search for life via spacecraft. The objective of the present study was to investigate the potential of Alexa-FISH (fluorescence in situ hybridization with Alexa Fluor® 488 labeled oligonucleotide) method as a molecular diagnostic tool for enumeration of multiple sterilant-resistant B. pumilus SAFR-032 spores artificially encapsulated in, and released via organic solvent from, a model polymeric material: poly(methylmethacrylate) (Lucite, Plexiglas). Plexiglas is used extensively in various aerospace applications and in medical, pharmaceutical and food industries. Alexa-FISH signals were not detected from spores via standard methods for vegetative bacterial cells. Optimization of a spore permeabilization protocol capitalizing on the synergistic action of proteinase-K, lysozyme, mutanolysin and Triton X-100 facilitated efficient spore detection by Alexa-FISH microscopy. Neither of the Alexa-probes tested gave rise to considerable levels of Lucite- or solvent-associated background autofluorescence, demonstrating the immense potential of Alexa-FISH for rapid quantification of encapsulated B. pumilus SAFR-032 spores released from poly(methylmethacrylate). PMID:22145981

  8. Angular dependence of the nanoDot OSL dosimeter

    PubMed Central

    Kerns, James R.; Kry, Stephen F.; Sahoo, Narayan; Followill, David S.; Ibbott, Geoffrey S.

    2011-01-01

    Purpose: Optically stimulated luminescent detectors (OSLDs) are quickly gaining popularity as passive dosimeters, with applications in medicine for linac output calibration verification, brachytherapy source verification, treatment plan quality assurance, and clinical dose measurements. With such wide applications, these dosimeters must be characterized for numerous factors affecting their response. The most abundant commercial OSLD is the InLight∕OSL system from Landauer, Inc. The purpose of this study was to examine the angular dependence of the nanoDot dosimeter, which is part of the InLight system.Methods: Relative dosimeter response data were taken at several angles in 6 and 18 MV photon beams, as well as a clinical proton beam. These measurements were done within a phantom at a depth beyond the build-up region. To verify the observed angular dependence, additional measurements were conducted as well as Monte Carlo simulations in MCNPX.Results: When irradiated with the incident photon beams parallel to the plane of the dosimeter, the nanoDot response was 4% lower at 6 MV and 3% lower at 18 MV than the response when irradiated with the incident beam normal to the plane of the dosimeter. Monte Carlo simulations at 6 MV showed similar results to the experimental values. Examination of the results in Monte Carlo suggests the cause as partial volume irradiation. In a clinical proton beam, no angular dependence was found.Conclusions: A nontrivial angular response of this OSLD was observed in photon beams. This factor may need to be accounted for when evaluating doses from photon beams incident from a variety of directions. PMID:21858992

  9. Implanted Dosimeters Identify Radiation Overdoses During IMRT for Prostate Cancer

    SciTech Connect

    Den, Robert B.; Nowak, Kamila; Buzurovic, Ivan; Cao Junsheng; Harrison, Amy S.; Lawrence, Yaacov R.; Dicker, Adam P.; Showalter, Timothy N.

    2012-07-01

    Purpose: Image-guided dose-escalated radiotherapy is the standard of care for the treatment of prostate cancer. Although many published methods are available that account for prostate motion during delivery, evidence demonstrating that the planned dose is actually delivered on a daily basis is lacking. We report our initial clinical experience using implantable dosimeters to quantify and adjust the dose received during intensity-modulated radiotherapy (IMRT). Methods and Materials: A total of 20 patients undergoing IMRT with cone-beam computed tomography (CT) image guidance for prostate cancer had the dose verification system with radiopaque metal-oxide-semiconductor field effect transistor dosimeters implanted before treatment planning. All patients underwent planning with CT simulation in the supine position with custom immobilization, and the implanted dosimeters were located in the IMRT plans. The predicted dose for each dosimeter was defined and compared with the wireless readings before and after each treatment session. Investigations by physicians and medical physicists were initiated for two or more discrepancies >6% for any five consecutive fractions or for any discrepancy {>=}10%. Results: Using implanted in vivo dosimeters, dose measurements consistently >6% greater than the predicted values were observed during treatment for 3 of 20 prostate cancer patients who received IMRT with daily image guidance. A review of the daily cone-beam CT images revealed acceptable alignment of the prostate target volumes and implanted dosimeters but identified significant anatomic changes within the treated region. Repeat CT simulation and RT planning was performed, with resolution of the dose discrepancies in all 3 cases with the adoption of a new IMRT plan. Conclusions: Our report illustrates the potential effect of implanted in vivo dosimetry for prostate IMRT and emphasizes the importance of careful planning and delivery with attention to systematic shifts or anatomic

  10. Development and evaluation of polycrystalline cadmium telluride dosimeters for accurate quality assurance in radiation therapy

    NASA Astrophysics Data System (ADS)

    Oh, K.; Han, M.; Kim, K.; Heo, Y.; Moon, C.; Park, S.; Nam, S.

    2016-02-01

    For quality assurance in radiation therapy, several types of dosimeters are used such as ionization chambers, radiographic films, thermo-luminescent dosimeter (TLD), and semiconductor dosimeters. Among them, semiconductor dosimeters are particularly useful for in vivo dosimeters or high dose gradient area such as the penumbra region because they are more sensitive and smaller in size compared to typical dosimeters. In this study, we developed and evaluated Cadmium Telluride (CdTe) dosimeters, one of the most promising semiconductor dosimeters due to their high quantum efficiency and charge collection efficiency. Such CdTe dosimeters include single crystal form and polycrystalline form depending upon the fabrication process. Both types of CdTe dosimeters are commercially available, but only the polycrystalline form is suitable for radiation dosimeters, since it is less affected by volumetric effect and energy dependence. To develop and evaluate polycrystalline CdTe dosimeters, polycrystalline CdTe films were prepared by thermal evaporation. After that, CdTeO3 layer, thin oxide layer, was deposited on top of the CdTe film by RF sputtering to improve charge carrier transport properties and to reduce leakage current. Also, the CdTeO3 layer which acts as a passivation layer help the dosimeter to reduce their sensitivity changes with repeated use due to radiation damage. Finally, the top and bottom electrodes, In/Ti and Pt, were used to have Schottky contact. Subsequently, the electrical properties under high energy photon beams from linear accelerator (LINAC), such as response coincidence, dose linearity, dose rate dependence, reproducibility, and percentage depth dose, were measured to evaluate polycrystalline CdTe dosimeters. In addition, we compared the experimental data of the dosimeter fabricated in this study with those of the silicon diode dosimeter and Thimble ionization chamber which widely used in routine dosimetry system and dose measurements for radiation

  11. Monte Carlo simulation experiments on box-type radon dosimeter

    NASA Astrophysics Data System (ADS)

    Jamil, Khalid; Kamran, Muhammad; Illahi, Ahsan; Manzoor, Shahid

    2014-11-01

    Epidemiological studies show that inhalation of radon gas (222Rn) may be carcinogenic especially to mine workers, people living in closed indoor energy conserved environments and underground dwellers. It is, therefore, of paramount importance to measure the 222Rn concentrations (Bq/m3) in indoors environments. For this purpose, box-type passive radon dosimeters employing ion track detector like CR-39 are widely used. Fraction of the number of radon alphas emitted in the volume of the box type dosimeter resulting in latent track formation on CR-39 is the latent track registration efficiency. Latent track registration efficiency is ultimately required to evaluate the radon concentration which consequently determines the effective dose and the radiological hazards. In this research, Monte Carlo simulation experiments were carried out to study the alpha latent track registration efficiency for box type radon dosimeter as a function of dosimeter's dimensions and range of alpha particles in air. Two different self developed Monte Carlo simulation techniques were employed namely: (a) Surface ratio (SURA) method and (b) Ray hitting (RAHI) method. Monte Carlo simulation experiments revealed that there are two types of efficiencies i.e. intrinsic efficiency (ηint) and alpha hit efficiency (ηhit). The ηint depends upon only on the dimensions of the dosimeter and ηhit depends both upon dimensions of the dosimeter and range of the alpha particles. The total latent track registration efficiency is the product of both intrinsic and hit efficiencies. It has been concluded that if diagonal length of box type dosimeter is kept smaller than the range of alpha particle then hit efficiency is achieved as 100%. Nevertheless the intrinsic efficiency keeps playing its role. The Monte Carlo simulation experimental results have been found helpful to understand the intricate track registration mechanisms in the box type dosimeter. This paper explains that how radon concentration from the

  12. Method of protecting a radiochromic optical waveguide dosimeter from adverse temperature effects. Patent Application

    SciTech Connect

    Kronenberg, S.

    1985-09-26

    A radiochromic optical waveguide dosimeter is protected from the adverse temperature effects of exposure in the desired operational temperature range of -40 C to +60 C by flattening the round plastic tubing to be used for the fabrication of the dosimeter until the tubing attains an elliptical cross section and then fabricating the dosimeter from the tubing having the elliptical cross section.

  13. Polymethylmethacrylate combustion in a narrow channel apparatus simulating a microgravity environment

    NASA Astrophysics Data System (ADS)

    Bornand, Garrett Randall

    Fire safety is an important part of engineering when human lives are at stake. From everyday homes to spacecraft that can cost hundreds of millions of dollars. The research in this thesis attempts to provide scientific evidence that the apparatus in question successfully simulates microgravity and can possibly replace NASA's current test method for spacecraft fire safety. Flame spread tests were conducted with thermally thick and thermally thin polymethylmethacrylate (PMMA) samples to study flame spread behavior in response to environmental changes. The tests were conducted using the San Diego State University Narrow Channel Apparatus (SDSU NCA) as well as within the Microgravity Science Glovebox (MSG) on the International Space Station (ISS). The SDSU NCA can suppress buoyant flow in horizontally spreading flames, and is currently being investigated as a possible replacement or complement to NASA's current material flammability test standard for non-metallic solids, NASA-STD-(I)-6001B Test 1. The buoyant suppression attained in the NCA allows tests to be conducted in a simulated microgravity environment-a characteristic that NASA's Test 1 lacks since flames present in Test 1 are driven by buoyant flows. The SDSU NCA allows for tests to be conducted at various opposed flow oxidizer velocities, oxygen percent by volume, and total pressure to mimic various spacecraft and habitat atmospheres. Tests were conducted at 1 atm pressure, thin fuel thickness of 50 and 75 microns, thick fuel thickness ranging from 3 mm to 5.6 mm, opposed oxidizer velocity ranging from 10 to 25 cm/s, and oxygen concentration by volume at 21, 30, and 50 percent. The simulated microgravity flame spread results were then compared to true microgravity experiments including; testing conducted on the International Space Station (ISS) under the Burning and Suppression of Solids (BASS) research, NASA's 5.2 second Drop Tower, and Micro-Gravity Laboratory's (MGLAB) 4.5 second Drop Tower. Data was also

  14. Anti-fatigue activity of polysaccharides extract from Radix Rehmanniae Preparata.

    PubMed

    Tan, Wei; Yu, Ke-qiang; Liu, Yan-yan; Ouyang, Ming-zi; Yan, Mei-hua; Luo, Ren; Zhao, Xiao-shan

    2012-01-01

    The anti-fatigue effects of the Radix Rehmanniae Preparata polysaccharides (RRPP) were studied in mice. The RRPP were orally administered at doses of 50, 100 and 200 mg/kg for 4 weeks and the anti-fatigue activity was evaluated using a weight-loaded swimming test, along with the determination of serum urea nitrogen (SUN), hepatic glycogen and blood lactic acid (BLA) contents. The results showed that there was no significant difference in the body weight of mice in the three RRPP groups compared with the negative control group during initial, intermediate and terminal stages in the experiment (p>0.05). The ratio of exhausting swimming time was obviously increased 31.48% (p<0.05) and 61.51% (p<0.01) in the middle-dose group and the high-dose RRPP group, respectively. The BLA and SUN levels were decreased in middle-dose and high-dose RRPP groups (p<0.01). Hepatic glycogen level was increased in three RRPP treated groups (p<0.01). Therefore, RRPP may be responsible for the pharmacological effect of anti-fatigue of Radix Rehmanniae Preparata. The mechanism was related to the increase of the storage of hepatic glycogen and the decrease of the accumulation of SUN and BLA. PMID:21983027

  15. Analysis of fingerprints features of infrared spectra of various processed products of Radix Aconiti kusnezoffii

    NASA Astrophysics Data System (ADS)

    Tu-ya; Yang, Ping; Sun, Su-qin; Zhou, Qun; Bao, Xiao-hua; Noda, Isao

    2010-06-01

    Fourier-transform infrared spectroscopy (FTIR) and two-dimensional correlation infrared spectroscopy (2D-IR)) are employed to analyze various processed products and ether extracts of Radix Aconiti kusnezoffii. There is a resemblance among the spectra of different processed products. The major difference lies in the absorption peak at 1641 cm -1 in the IR spectra, which reflects the transformation of raw aconite to the processed products. There are distinctive differences in the absorption peaks in the range of 1800-1500 cm -1 in the second derivative spectra, which has better resolution, of different processed products. 2D-IR spectra, which elevate the resolution further, can present even more differences among the products in the range of 1800-800 cm -1. Analysis of ether extracts of various processed products proves that there are alcohols, esters, carboxylic acids or ketones in all of them. However, their contents in different samples have obvious differences. With the advantages of high resolution, high-speed and convenience, IR can quickly and precisely distinguish various processed products of Radix A. kusnezoffii, and can be applied to predict the tendency of transformation of the complicated chemical mixture systems under heat perturbation.

  16. In vivo anti-inflammatory activities of the essential oil from Radix Angelicae dahuricae.

    PubMed

    Wang, Chunmei; Sun, Jingbo; Li, He; Yang, Xue; Liu, Huimin; Chen, Jianguang

    2016-07-01

    Although Radix Angelicae dahuricae (Angelica) has been traditionally used in patients with rheumatism arthralgia, its bioactive ingredients remain to be determined. In this study, the essential oil extract of Radix Angelicae dahuricae (EOAD) was assessed for its anti-inflammatory activities against xylene-induced acute ear swelling and carrageenan-induced acute paw edema in mice as well as its anti-inflammatory and immunomodulating properties in Freund's complete adjuvant (FCA)-induced arthritis in rats. We found that EOAD at 100 mg/kg significantly alleviated xylene-induced ear swelling and carrageenan-induced paw edema in mice. Moreover, in the FCA-induced rat arthritis model, EOAD significantly improved hind paw swelling, lowered the adjuvant arthritis score, mitigated synovial hyperplasia, inflammatory cell infiltration, and cartilage destruction in the ankle joint, and reduced the serum levels of inflammatory mediators such as nitric oxide, tumor necrosis factor-α, and prostaglandin E2 as well as serum nitric oxide synthase activity. These findings support the fact that the essential oil extract of Angelica contains important active constituents responsible for its anti-inflammatory activities and therefore help to understand the phytotherapeutic effects of Angelica in the treatment of aseptic inflammation. PMID:26906120

  17. [Rapid discriminant analysis of sulfur fumigated Puerariae Lobatae Radix based on vertical and horizontal surfaces].

    PubMed

    Wu, Zhi-sheng; Du, Min; Pan, Xiao-ning; Zhao, Na; Shi, Xin-yuan; Qiao, Yan-jiang

    2015-06-01

    Near-infrared (NIR) was used as rapid analysis method to identify the sulfur fumigated Puerariae Lobatae Radix. NIR spectra of the cross-sectional and longitudinal selection of samples were acquired. Principal component analysis was conducted. The samples were randomly selected. The different pretreatment methods were compared. Discriminant models were established for every type of spectra to calculate the recognition rate. The orthogonal test and nonparametric test were used to test data normality. The result showed that absorbance values of different sections were different due to the different structure, and the raw spectra were analyzed by PCA method. The result founded that the cumulative contribution rate was arrived at 99.2% while the PC numbers were arrived at 3. The pretreatment method based on the MSC + 1D + Savitzky-Golay was the best to establish the model. For the 50 models constructed with cross-section and longitudinal spectra and total spectra, the recognition rate were (94.4 ± 0.66)%, (94.4 ± 0.66)%, (95.3 ± 0.65)%, respectively, and no difference was observed. The NIR method could be used to identify the sulfur fumigated Puerariae Lobatae Radix. PMID:26591520

  18. Large scale purification of puerarin from Puerariae Lobatae Radix through resins adsorption and acid hydrolysis.

    PubMed

    Guo, Hai-Dong; Zhang, Qing-Feng; Chen, Ji-Guang; Shangguang, Xin-Cheng; Guo, Yu-Xian

    2015-02-01

    Puerarin is the major isoflavone of Puerariae Lobatae Radix. A method for large scale purification of puerarin was developed through resins adsorption and acid hydrolysis. The adsorption properties of six macroporous resins (D101, S-8, H103, X-5, HPD600, AB-8) were compared through the adsorption kinetics and equilibrium adsorption isotherms. Results showed that H103 resin had the best adsorption rate and capacity. The mass transfer zone motion model was further used for analyzing the fixed bed adsorption of H103 resin. Its length of mass transfer zone with 2mg/ml of puerarin in water and 10% ethanol at flow rate of 10ml/min were 41.6 and 47.5cm, while the equilibrium adsorption capacity was 165.03 and 102.88mg/g, respectively. By using 75% ethanol, puerarin could be well desorbed from the resin with recovery of 97.4%. Subsequently, H103 resin was successfully used for puerarin purification from Puerariae Lobatae Radix. The content of total isoflavones and puerarin in the resin adsorption product were 69.25% and 41.78%, respectively, which were about three times increased compared to the crude extract. Then, the product was hydrolyzed by 2.5M HCl at 90°C for 1h. Puerarin with purity of 90% and a byproduct daidzein with purity of 78% were obtained. PMID:25553536

  19. Platycodi Radix suppresses development of atopic dermatitis-like skin lesions.

    PubMed

    Choi, Jae Ho; Han, Eun Hee; Park, Bong Hwan; Kim, Hyung Gyun; Hwang, Yong Pil; Chung, Young Chul; Lee, Young Chun; Jeong, Hye Gwang

    2012-05-01

    Platycodi Radix has been used to treat chronic diseases, such as bronchitis, asthma, and hyperlipidemia. In this study, we examined the effect of an aqueous extract, Changkil (CK), from the root of Platycodi Radix on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions. Administration of CK onto DNCB-induced AD-like skin lesions in NC/Nga mice ameliorated lesion intensity scores, levels of IgE, thymus and activation-regulated chemokine (TARC), TNF-α, and IL-4 in serum and ears. In contrast, CK increased level of the immunosuppressive cytokine IL-10. Histopathological examination showed reduced thickness of the epidermis/dermis and dermal infiltration of inflammatory cells in the ears. CK also suppressed TNF-α/IFN-γ-induced mRNA expression and production of TARC in HaCaT cells. CK exerts beneficial effects on AD symptoms, suggesting that CK is an effective potential therapeutic agent for AD. PMID:22407167

  20. Analysis of essential oils and fatty acids from Platycodi Radix using chemometric methods and retention indices.

    PubMed

    He, Min; Li, Yaping; Yan, Jun; Cao, Dongsheng; Liang, Yizeng

    2013-04-01

    The chemical composition of the essential oils and fatty acids among nine groups of Platycodi Radix in China was analyzed by gas chromatography-mass spectrometry. Complicated components were resolved using chemometric methods. Simultaneously, the various features among heuristic evolving latent projections, selective ion analysis and alternative moving window factor analysis were compared by using some experimental data. Temperature-programmed retention indices were applied in further identification of the chemical composition of the essential oils. The equivalent chain length, fraction chain length, and an established special retention indices library integrated with mass spectrometry were also applied to further identify the composition of fatty acids, including total fatty acids, esterified fatty acids and free fatty acids. A total of 121 different compounds accounting for 95.12-98.74% were identified among the essential oils. Chemical polymorphisms and variation existed in the essential oils of Platycodi Radix. Sixteen components were identified in fatty acids, and linoleic acid (18:2n-6c) and other unsaturated acid possess a characteristic majority. PMID:22964951

  1. Cryptotanshinone from Salviae miltiorrhizae radix inhibits sodium-nitroprusside-induced apoptosis in neuro-2a cells.

    PubMed

    Mahesh, Ramalingam; Jung, Hyo Won; Kim, Gun Woo; Kim, Young Shik; Park, Yong-Ki

    2012-08-01

    The root of Salvia miltiorrhiza (Salviae miltiorrhizae radix), a herbal medicine has widely been used for the treatment of pain, miscarriage and oedema. In this study, we evaluated the neuroprotective effect of cryptotanshinone (CRT) from Salviae miltiorrhizae radix on sodium-nitroprusside (SNP)-induced apoptosis in neuro-2a (N2a) cells, and further investigated its action mechanism in signalling pathways. The effects of CRT against SNP-induced toxicity, mitochondrial membrane potential (MMP) changes, and oxidants/antioxidant defences and apoptotic signalling pathways were investigated in N2a cells. Cryptotanshinone significantly inhibited SNP-induced cell toxicity and the generation of reactive oxygen and nitrogen species (RONS), and improved MMP in N2a cells. Cryptotanshinone significantly suppressed SNP-induced peroxidation of lipid and protein, and the expression of Gclc mRNA. In the signalling pathway, CRT effectively blocked SNP-induced activation of NF-κB and ERK1/2 and JNK MAPK pathways through the elevation of Akt and cyclic AMP response element binding protein. Furthermore, CRT remarkably reduced the increase of mitochondrial Bax/Bcl-2 ratio, the release of cytochrome c from mitochondria to cytosol, and the activations of cytosolic procaspase-3 and nuclear inactive poly ADP (adenosine diphosphate)-ribose polymerase by SNP-induced apoptosis. These results indicate that CRT has neuroprotective effects against SNP-induced apoptosis in neuronal cells via the regulation of mitochondrial apoptotic cascades and antiapoptotic cellular signalling pathways. PMID:22228596

  2. Effects of Lipid Regulation Using Raw and Processed Radix Polygoni Multiflori in Rats Fed a High-Fat Diet

    PubMed Central

    Li, Na; Chen, Zhen; Mao, Xiaojian; Yu, Jie; Zhao, Ronghua

    2012-01-01

    Raw and processed Radix Polygoni Multiflori have been used in the prevention and treatment of nonalcoholic fatty liver disease (NAFLD), hyperlipidemia, and related diseases in Asian counties for centuries. The lipid regulation ability of raw and processed Poligoni Multiflori Radix were compared in high-fat diet fed rats in this research. Total cholesterol (TC) and low density lipoprotein-cholesterol (LDL-C) in blood and liver tissue were all significantly higher in model rats. However, triglyceride (TG) contents increased only in liver tissue, not in the blood samples. The rats fed the high-fat diets were considered the model of type IIa hyperlipidemia and early-stage nonalcoholic fatty liver disease. Both Radix Polygoni Multiflori (RPM) and Radix Polygoni Multiflori Praeparata (RPMP) revealed TC-lowing effects, and middling doses of RPMP displayed the most significant TC-lowing effects, as indicated by blood samples. Neither RPM nor RPMP was found to reduce LDL-C in rats' blood. Nevertheless, RPM showed dose-dependent TC- and TG-lowing effects in the liver tissue samples. In conclusion, RPM showed more pronounced effects on lipid regulation in liver samples in the treatment of early-stage NAFLD. RPMP, however, displayed better effects in regulating lipids in circulating blood for the treatment of hyperlipidemia. PMID:23304197

  3. An Aqueous Extract of Radix Astragali, Angelica sinensis, and Panax notoginseng Is Effective in Preventing Diabetic Retinopathy

    PubMed Central

    Gao, Dehong; Guo, Yijuan; Li, Xuejun; Li, Xiumin; Li, Zhipeng; Xue, Mei; Ou, Zhimin; Liu, Ming; Yang, Mingxing; Liu, Suhuan; Yang, Shuyu

    2013-01-01

    Diabetic retinopathy (DR), in which inflammation has been implicated playing important roles, is one of the most common diabetes complications. Dang Gui Bu Xue Tang (DBT), an aqueous extract of Radix Astragali and Radix Angelica sinensis, is a classical prescription in Traditional Chinese Medicine for treating inflammation and ischemic diseases. Here, we investigated the effects of a modified recipe of DBT, with addition of Panax notoginseng, in treating diabetic retinopathy. An aqueous extract of Radix Astragali, Radix Angelica sinensis, and Panax notoginseng (RRP) was given to Goto-Kakizaki (GK) rats and streptozotocin-induced Sprague-Dawley (SD) rats. Leukostasis, vascular leakage, and acellular capillaries in retinal vasculature of animals were determined. Expression of retinal inflammatory biomarkers was assessed. We found that RRP reduced leukostasis, acellular capillaries, and vascular leakage compared to diabetic control rats. We also found that RRP decreased the expression of inflammatory factors including IL-1β, IL-6, TNF-α, NF-κB, MCP-1, ICAM-1, or VCAM-1 in the retinas of GK rats and reversed high glucose-induced inhibition of endothelial cell migration and proliferation in vitro. We conclude that RRP has a potent effect in preventing the pathogenesis and/or progression of DR and thus may serve as a promising nontoxic therapeutic approach of DR. PMID:23662142

  4. Anticancer potential of an ethanol extract of Asiasari radix against HCT-116 human colon cancer cells in vitro.

    PubMed

    Oh, Se-Mi; Kim, Jinhee; Lee, Jun; Yi, Jin-Mu; Oh, Dal-Seok; Bang, Ok-Sun; Kim, No Soo

    2013-01-01

    Radix of Asiasarum heterotropoides var. mandshuricum F. Maekawa (A. radix) has been prescribed for treating pain, allergies and inflammatory disorders in traditional oriental medicine. However, only limited information on the anticancer effects of A. radix is currently available. The aim of this study was to determine the anticancer effect of the ethanol extract of A. radix (EEAR) on HCT-116 human colon cancer cells and to investigate its underlying mechanisms of action. EEAR significantly induced G2/M cell cycle arrest and apoptosis in HCT-116 cells. EEAR-induced apoptosis was observed in parallel with activation of caspases and an increased ratio of Bax (pro-apoptotic)/Bcl2 (anti-apoptotic). Western blot analyses revealed that EEAR elevated the expression of p53 and p21(Waf/Cip1) and decreased the expression of the regulator proteins of G2/M phase progression, such as cdc2 and cyclin B. The upregulation of p53 by EEAR was due to the increased levels of p53 mRNA without a similar increase in proteasome-mediated p53 degradation. EEAR-induced apoptosis in HCT-116 cells was dependent on p53 expression, as determined by siRNA-mediated p53 knockdown. Taken together, these results suggest that EEAR inhibits the growth of the HCT-116 cells through induction of G2/M cell cycle arrest and apoptosis, which are mediated by p53 expression. PMID:23255939

  5. Hanford Personnel Dosimeter supporting studies FY-1980. [Lead abstract

    SciTech Connect

    Endres, G.W.R.; Cummings, F.M.; Aldrich, J.M.; Thorson, M.R.; Kathren, R.L.

    1981-02-01

    Separate abstracts were prepared for the 10 sections of this report which describe fundamental characteristics of the Hanford multipurpose personnel dosimeter (HMPD). Abstracts were not prepared for Appendix A and Appendix B which deal with calculated standard deviations for 100 mrem mixed field exposures and detailed calculations of standard deviations, respectively. (KRM)

  6. Development of an improved fingertip dosimeter for beta radiation

    SciTech Connect

    Couch, N.W.

    1986-01-01

    The dosimeter employs a multi-element, multi-filter concept by stacking four 0.13 mm LiF-teflon TLD's to form the beta detector element. The entire dosimeter is approximately 1 mm thick, flexible, and rugged enough for field use without interference with the manual dexterity of the user. The fingertip dosimeter provides data for determining the beta energy of each exposure. The beta energy can be used to determine the TLD response factor for correcting the TLD output to beta dose in mrad. The data can be used to reconstruct the beta depth dose curve due to single beta or mixed beta exposures. For mixed beta/gamma exposures, the addition of a gamma measuring element would provide data for separating the gamma component for the beta component. The depth dose curve can be used to calculate the beta doses in tissue at 7 mg/cm/sup 2/, for legal reporting purposes, or at any other desired depth within the range of the beta radiation. The fingertip dosimeter was used to monitor extremity beta doses for research lab personnel. The results showed higher fingertip beta doses than had previously been expected. The average monthly beta dose was shown to be approximately 0.5 rad/mo.

  7. Thin thermoluminescent dosimeter and method of making same

    DOEpatents

    Simons, Gale G.; DeBey, Timothy M.

    1987-01-01

    An improved thermoluminescent ionizing radiation dosimeter of solid, extremely thin construction for more accurate low energy beta dosimetry is provided, along with a method of fabricating the dosimeter. In preferred forms, the dosimeter is a composite including a backing support (which may be tissue equivalent) and a self-sustaining body of solid thermoluminescent material such as LiF having a thickness of less than about 0.25 millimeters and a volume of at least about 0.0125 mm.sup.3. In preferred fabrication procedures, an initially thick (e.g., 0.89 millimeters) TLD body is wet sanded using 600 grit or less sandpaper to a thickness of less than about 0.25 millimeters, followed by adhesively attaching the sanded body to an appropriate backing. The sanding procedure permits routine production of extremely thin (about 0.05 millimeters) TLD bodies, and moreover serves to significantly reduce non-radiation-induced thermoluminescence. The composite dosimeters are rugged in use and can be subjected to annealing temperatures for increased accuracy.

  8. Characterization of a reusable PRESAGE® 3D dosimeter

    NASA Astrophysics Data System (ADS)

    Juang, T.; Adamovics, J.; Oldham, M.

    2015-01-01

    This study investigates a reusable PRESAGE® 3D dosimeter (Presage-RU), which would improve cost-effectiveness and facilitate wider implementation of comprehensive, high resolution 3D dosimetry. Small (1x1x4.5 cm) and large (8 cm diameter, 4.5 cm length) sample dosimeters were irradiated multiple times to characterize dose response (i.e. radiation-induced change in optical density (ΔOD)), optical clearing rate, and dose distribution stability. Presage- RU exhibited an initial dose response sensitivity of 0.0119 ΔOD/(cm-Gy), a reduction in response with subsequent irradiations, and a small, permanent ΔOD (~1-6% of initial signal) following each irradiation. Dosimeters optically cleared at an exponential rate (average T1/2 = 24.8±3.6 h), and were effectively cleared after ~5-8 days. 3D gamma analysis (3%/3mm, 10% dose threshold) of a 4-field box plan applied to the large dosimeter showed good agreement following initial irradiation (96.6% passing), but a reduction in passing rate (89.1% passing) with subsequent irradiation. Further study is warranted to fully assess and quantify the performance of Presage-RU for repeat irradiations.

  9. Two methods for examining angular response of personnel dosimeters

    SciTech Connect

    Plato, P.; Leib, R.; Miklos, J.

    1988-06-01

    The American National Standard ANSI N13.11-1983 is used to test the accuracy (bias plus precision) of dosimetry processors as part of the dosimetry accreditation program of the National Voluntary Laboratory Accreditation Program (NVLAP). Section 3.8 of the ANSI N13.11-1983 standard requires that a study of the angular response of a dosimeter be carried out once, although no pass/fail criterion is given for angular response. The NVLAP accreditation program excluded Section 3.8, and thus no angular response data have been generated in an organized fashion. The objective of this project is to examine the feasibility of two alternative methods to test the angular response of personnel dosimeters. The first alternative involves static irradiations with the dosimeters at fixed angles to a radiation source. The second alternative involves dynamic irradiations with the dosimeters mounted on a rotating phantom. A Panasonic UD-802 personnel dosimetry system** was used to generate data to examine both alternatives. The results lead to two major conclusions. Firstly, Section 3.8 of the ANSI N13.11-1983 standard should be amended to require a pass/fail test for angular response. Secondly, a comparison between angular response data generated with a fixed or a rotating phantom shows that the rotating phantom is the more cost-effective method.

  10. Portable battery-free charger for radiation dosimeters

    DOEpatents

    Manning, Frank W.

    1984-01-01

    This invention is a novel portable charger for dosimeters of the electrometer type. The charger does not require batteries or piezoelectric crystals and is of rugged construction. In a preferred embodiment, the charge includes a housing which carries means for mounting a dosimeter to be charged. The housing also includes contact means for impressing a charging voltage across the mounted dosimeter. Also, the housing carries a trigger for operating a charging system mounted in the housing. The charging system includes a magnetic loop including a permanent magnet for establishing a magnetic field through the loop. A segment of the loop is coupled to the trigger for movement thereby to positions opening and closing the loop. A coil inductively coupled with the loop generates coil-generated voltage pulses when the trigger is operated to open and close the loop. The charging system includes an electrical circuit for impressing voltage pulses from the coil across a capacitor for integrating the pulses and applying the resulting integrated voltage across the above-mentioned contact means for charging the dosimeter.

  11. Influence of preparation and calibration method of PAGAT dosimeter on TSE MR readout results

    NASA Astrophysics Data System (ADS)

    Vávrů, K.; Dvořák, P.; Tintěra, J.; Spěváček, V.

    2013-06-01

    In this study PAGAT dosimeter evaluation by TSE sequence was tested. PAGAT dosimeter preparation procedure was modified to increase the dosimeter sensitivity. Because THPC reacts with gelatin, adding THPC to monomer solution prior to dissolved gelatine helps exploit THPC as an antioxidant. Turbo spin echo sequence enables to evaluate gel dosimeter with 3D equidistant resolution in a reasonable scanning time. Glass walls of the phantom cause problems both by computing inaccuracies and MR imaging artefacts. The inner dosimeter volume is not affected by these inaccuracies and should be used for radiotherapy plan verification.

  12. Deconnable self-reading pocket dosimeter containment with self-contained light

    SciTech Connect

    Stevens, R.L.; Arnold, G.N.; McBride, R.G.

    1995-12-31

    A container for a self-reading pocket dosimeter includes a transparent tube for receiving the self-reading pocket dosimeter, a light source mounted at one end of the transparent tube, and an eyepiece mounted on an opposite end of the transparent tube for viewing a read-out of the self-reading pocket dosimeter. The container may further include an activation device for selectively supplying power to the light source. The container both protects the dosimeter from being contaminated and provides a light source for viewing the dosimeter.

  13. Deconnable self-reading pocket dosimeter containment with self-contained light

    DOEpatents

    Stevens, Robyn L.; Arnold, Greg N.; McBride, Ryan G.

    1996-01-01

    A container for a self-reading pocket dosimeter includes a transparent tube for receiving the self-reading pocket dosimeter, a light source mounted at one end of the transparent tube, and an eyepiece mounted on an opposite end of the transparent tube for viewing a read-out of the self-reading pocket dosimeter. The container may further include an activation device for selectively supplying power to the light source. The container both protects the dosimeter from being contaminated and provides a light source for viewing the dosimeter.

  14. VALIDATION OF HANFORD PERSONNEL AND EXTREMITY DOSIMETERS IN PLUTONIUM ENVIRONMENTS

    SciTech Connect

    Scherpelz, Robert I.; Fix, John J.; Rathbone, Bruce A.

    2000-02-10

    A study was performed in the Plutonium Finishing Plant to assess the performance of Hanford personnel neutron dosimetry. The study was assessed whole body dosimetry and extremity dosimetry performance. For both parts of the study, the TEPC was used as the principle instrument for characterizing workplace neutron fields. In the whole body study, 12.7-cm-diameter TEPCs were used in ten different locations in the facility. TLD and TED personnel dosimeters were exposed on a water-filled phantom to enable a comparison of TEPC and dosimeter response. In the extremity study, 1.27-cm-diameter TEPCs were exposed inside the fingers of a gloveboxe glove. Extremity dosimeters were wrapped around the TEPCs. The glove was then exposed to six different cans of plutonium, simulating the exposure that a worker's fingers would receive in a glovebox. The comparison of TEPC-measured neutron dose equivalent to TLD-measured gamma dose equivalent provided neutron-to-gamma ratios that can be used to estimate the neutron dose equivalent received by a worker's finger based on the gamma readings of an extremity dosimeter. The study also utilized a Snoopy and detectors based on bubble technology for assessing neutron exposures, providing a comparison of the effectiveness of these instruments for workplace monitoring. The study concludes that the TLD component of the HCND performs adequately overall, with a positive bias of 30%, but exhibits excessive variability in individual results due to instabilities in the algorithm. The TED response was less variable but only 20% of the TEPC reference dose on average because of the low neutron energies involved. The neutron response of the HSD was more variable than the TLD component of the HCND and biased high by a factor of 8 overall due to its calibration to unmoderated 252Cf. The study recommends further work to correct instabilities in the HCND algorithm and to explore the potential shown by the bubble-based dosimeters.

  15. Quantitative Analysis and In vitro Anti-inflammatory Effects of Gallic Acid, Ellagic Acid, and Quercetin from Radix Sanguisorbae

    PubMed Central

    Seo, Chang-Seob; Jeong, Soo-Jin; Yoo, Sae-Rom; Lee, Na-Ri; Shin, Hyeun-Kyoo

    2016-01-01

    Background: Radix Sanguisorbae has long been used to treat diarrhea, enteritis, duodenal ulcers, and internal hemorrhage. Objective: We investigated the in vitro anti-inflammatory effects of Radix Sanguisorbae and performed quantitative analyses of three marker components, namely gallic acid, ellagic acid, and quercetin, using high-performance liquid chromatography coupled with a photodiode array detector. Materials and Methods: The three marker components were separated using a reversed-phase Gemini C18 analytical column maintained at 40°C by the gradient elution with two solvent systems. We examined the biological effects of the three marker compounds, gallic acid, ellagic acid, and quercetin, by determining their anti-inflammatory activities in the murine macrophage cell line RAW 264.7. Results: All of the marker compounds exhibited inhibitory effects on prostaglandin E2 production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, with no cytotoxicity. Particularly, ellagic acid significantly inhibited production of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-6 in LPS-treated RAW 264.7 cells. Conclusion: Our results suggest that ellagic acid is the most potent bioactive phytochemical component of radix Sanguisorbae in the treatment of inflammatory diseases. SUMMARY Established high-performance liquid chromatography method was applied in the quantitative analysis of gallic acid, ellagic acid, and quercetin present in an extract from radix SanguisorbaeAmong the three compounds, the ellagic acid.(7.65.mg/g) is main component in radix SanguisorbaeEllagic acid significantly inhibited production of the proinflammatory cytokines tumor necrosis factor alpha and interleukin-6 in lipopolysaccharide-treated RAW 264.7 cells. Abbreviations used: HPLC: High-performance liquid chromatography, PDA: Photodiode array, TNF-α: Tumor necrosis factor alpha, IL: Interleukin, LPS: Lipopolysaccharide, PGE2: Prostaglandin E2, NSAIDs

  16. Delayed granulomatous reactions to facial cosmetic injections of polymethylmethacrylate microspheres and liquid injectable silicone: A case series.

    PubMed

    Friedmann, Daniel P; Kurian, Anil; Fitzpatrick, Richard E

    2016-06-01

    Polymethylmethacrylate microsphere (PMMA) and liquid injectable silicone (LIS) fillers are non-biodegradable, synthetic polymers utilized for long-term soft-tissue augmentation. Delayed granulomatous reactions to permanent fillers are a rare yet significant event that can occur months to years post procedure and are often refractory to treatment and associated with significant cosmetic morbidity. We report a case series of 4 patients who developed granulomatous reactions to PMMA or LIS, 15 months to 5 years post injection. The etiology of granulomatous reactions to permanent fillers is still poorly understood, with foreign-body reactions and/or biofilms purported to play a role. Real-time biochemical analysis with polymerase chain reaction should be performed when the index of suspicion for the presence of a biofilm is high. PMID:26735450

  17. Effects of polymethylmethacrylate-transfer residues on the growth of organic semiconductor molecules on chemical vapor deposited graphene

    SciTech Connect

    Kratzer, Markus Teichert, Christian; Bayer, Bernhard C.; Kidambi, Piran R.; Matković, Aleksandar; Gajić, Radoš; Cabrero-Vilatela, Andrea; Weatherup, Robert S.; Hofmann, Stephan

    2015-03-09

    Scalably grown and transferred graphene is a highly promising material for organic electronic applications, but controlled interfacing of graphene thereby remains a key challenge. Here, we study the growth characteristics of the important organic semiconductor molecule para-hexaphenyl (6P) on chemical vapor deposited graphene that has been transferred with polymethylmethacrylate (PMMA) onto oxidized Si wafer supports. A particular focus is on the influence of PMMA residual contamination, which we systematically reduce by H{sub 2} annealing prior to 6P deposition. We find that 6P grows in a flat-lying needle-type morphology, surprisingly independent of the level of PMMA residue and of graphene defects. Wrinkles in the graphene typically act as preferential nucleation centers. Residual PMMA does however limit the length of the resulting 6P needles by restricting molecular diffusion/attachment. We discuss the implications for organic device fabrication, with particular regard to contamination and defect tolerance.

  18. Influence of silver nanoparticles on relaxation processes and efficiency of dipole - dipole energy transfer between dye molecules in polymethylmethacrylate films

    NASA Astrophysics Data System (ADS)

    Bryukhanov, V. V.; Konstantinova, E. I.; Borkunov, R. Yu; Tsarkov, M. V.; Slezhkin, V. A.

    2015-10-01

    The fluorescence and phosphorescence of dyes in thin polymethylmethacrylate (PMMA) films in the presence of ablated silver nanoparticles has been investigated in a wide temperature range by methods of femtosecond and picosecond laser photoexcitation. The fluorescence and phosphorescence times, as well as spectral and kinetic characteristics of rhodamine 6G (R6G) molecules in PMMA films are measured in a temperature range of 80 - 330 K. The temperature quenching activation energy of the fluorescence of R6G molecules in the presence of ablated silver nanoparticles is found. The vibrational relaxation rate of R6G in PMMA films is estimated, the efficiency of the dipole - dipole electron energy transfer between R6G and brilliant green molecules (enhanced by plasmonic interaction with ablated silver nanoparticles) is analysed, and the constants of this energy transfer are determined.

  19. Modification of cellulose nanocrystal via SI-ATRP of styrene and the mechanism of its reinforcement of polymethylmethacrylate.

    PubMed

    Yin, Y; Tian, X; Jiang, X; Wang, H; Gao, W

    2016-05-20

    Cellulose nanocrystal (CNC) is a promising strengthener but is used limitedly since its poor compatibility with organic materials. The graft polymerization of styrene via surface-initiated atom transfer radical polymerization (SI-ATRP) of cellulose nanocrystal is adopted to modify its thermo-stability and compatibility. The modified crystals have been dosed into polymethylmethacrylate (PMMA) nanocomposites by the solution casting. The polymeric layer on the surface of CNCs should improve the thermal stability of CNCs, and provide significant dispersibility and compatibilization for the nanocomposites. Thermogravimetry analysis proved that the initial degrade temperature of CNC was increased 50 °C with the modification. The scanning electronic microscope showed that the modified CNCs homogeneously dispersed in PMMA matrix. Breaking strength and elongation at break of the composites were improved, which was attributed to the reinforcement of CNCs modified with styrene. Transmittance of nanocomposite films measurement showed that the transmittance of PMMA/1%CNC was almost close to that of pure PMMA. PMID:26917392

  20. On-line and post irradiation analysis of swift heavy ion induced modification of PMMA (polymethyl-methacrylate)

    NASA Astrophysics Data System (ADS)

    Hossain, U. H.; Lima, V.; Baake, O.; Severin, D.; Bender, M.; Ensinger, W.

    2014-05-01

    The present work is part of a research program studying the swift heavy ion induced modification of aliphatic polymers with some comparable side groups, here polymethyl-methacrylate (PMMA). This paper presents a study on Fourier-transform-infrared spectroscopy (FTIR), residual gas analysis (RGA), and Ultraviolet-Visible (UV-Vis) spectroscopy of the transformations of a PMMA film under gold (Au) and uranium (U) ion irradiation in the MeV/u range in vacuum to fluences up to 3 × 1011 ions per cm2. The results show a general ion induced degradation of the polymer, with release of volatile fragments, scission of side chains and polymeric backbone, formation of conjugated double bonds, and the resulting increased absorption of the UV part in the UV-Vis spectral region. A molecular scission mechanism which explains the main degradation products is proposed.

  1. A Signal-Inducing Bone Cement for Magnetic Resonance Imaging-Guided Spinal Surgery Based on Hydroxyapatite and Polymethylmethacrylate

    SciTech Connect

    Wichlas, Florian Seebauer, Christian J.; Schilling, Rene; Rump, Jens; Chopra, Sascha S.; Walter, Thula; Teichgraeber, Ulf K. M.; Bail, Hermann J.

    2012-06-15

    The aim of this study was to develop a signal-inducing bone cement for magnetic resonance imaging (MRI)-guided cementoplasty of the spine. This MRI cement would allow precise and controlled injection of cement into pathologic lesions of the bone. We mixed conventional polymethylmethacrylate bone cement (PMMA; 5 ml methylmethacrylate and 12 g polymethylmethacrylate) with hydroxyapatite (HA) bone substitute (2-4 ml) and a gadolinium-based contrast agent (CA; 0-60 {mu}l). The contrast-to-noise ratio (CNR) of different CA doses was measured in an open 1.0-Tesla scanner for fast T1W Turbo-Spin-Echo (TSE) and T1W TSE pulse sequences to determine the highest signal. We simulated MRI-guided cementoplasty in cadaveric spines. Compressive strength of the cements was tested. The highest CNR was (1) 87.3 (SD 2.9) in fast T1W TSE for cements with 4 {mu}l CA/ml HA (4 ml) and (2) 60.8 (SD 2.4) in T1W TSE for cements with 1 {mu}l CA/ml HA (4 ml). MRI-guided cementoplasty in cadaveric spine was feasible. Compressive strength decreased with increasing amounts of HA from 46.7 MPa (2 ml HA) to 28.0 MPa (4 ml HA). An MRI-compatible cement based on PMMA, HA, and CA is feasible and clearly visible on MRI images. MRI-guided spinal cementoplasty using this cement would permit direct visualization of the cement, the pathologic process, and the anatomical surroundings.

  2. [Rapid identification of crude and sweated dipsaci radix based on near-infrared spectroscopy combined with principal component analysis-mahalanobis distance].

    PubMed

    Du, Wei-Feng; Jia, Yong-Qiang; Jiang, Dong-Jing; Zhang, Hao

    2014-12-01

    In order to discriminate the crude and sweated Dipsaci Radix correctly and rapidly, the crude and sweated Dipsaci Radix were scanned by the NIR spectrometer, and an identifying model was developed by near infrared spectroscopy combined with principal component-Mahalanobis distance pattern recognition method. The pretreated spectra data of 129 crude samples and 86 sweated ones were analyzed through principal component analysis (PCA). The identifying model was developed by choosing the spectrum for 9 881.46-4 119.20 cm(-1) and "SNV + spectrum + S-G" to the original spectral preprocessing with 14 principal components, and then was verified by prediction set, identifying with 100% accuracy. The rapid identification model of the crude and sweated Dipsaci Radix by NIR is feasible and efficient, and could be used as an assistant means for identifying the crude and sweated Dipsaci Radix. PMID:25911809

  3. Rapid and undamaged analysis of crude and processed Radix Scrophulariae by Fourier transform infrared spectroscopy coupled with soft independent modeling of class analogy

    PubMed Central

    Zhu, Huiping; Cao, Gang; Cai, Hao; Cai, Baochang; Hu, Jue

    2014-01-01

    Objective: The main objective of this work is to determine the feasibility of identification of crude and processed Radix Scrophulariae using the Fourier transform infrared spectroscopy couple with soft independent modeling of class analogy (FT-IR-SIMCA). Materials and Methods: A total of 50 different crude Radix Scrophulariae was used to product processed ones. The spectra were acquired by FT-IR spectroscopy using a diffuse reflectance fiber optic probe. For the multivariate analysis, SIMCA was used. Results showed that FT-IR-SIMCA was useful to discriminate the processed Radix Scrophulariae samples from crude samples. These samples could be successfully classified by SIMCA. Results: In all cases, the recognition and rejection rates were 97.8% and 100%, respectively. When testing with the blind sample that was picked out from the chosen samples, the accuracy was up to 90%. Conclusion: It means that the methodology is capable of accurately separating processed Radix Scrophulariae from crude samples. PMID:25210313

  4. Determination of Ruscogenin in Ophiopogonis Radix by High-performance Liquid Chromatography-evaporative Light Scattering Detector Coupled with Hierarchical Clustering Analysis

    PubMed Central

    Liu, Chun-Hua; Li, Ming; Feng, Ya-Qian; Hu, Yuan-Jia; Yu, Bo-Yang; Qi, Jin

    2016-01-01

    Background: Ophiopogonis Radix is a famous traditional Chinese medicine. It is necessary to establish a suitable quality control methods of Ophiopogonis Radix. Objective: To investigate the quality control methods of Ophiopogonis Radix by high-performance liquid chromatography (HPLC) coupled with evaporative light scattering detector (ELSD). Materials and Methods: A rapid and simple method, HPLC coupled with ELSD, was applied to determinate ruscogenin in 35 batches of Ophiopogenis Radix samples. Orthogonal tests and single factor explorations were used to optimize the extraction condition of ruscogenin. The content of ruscogenin in different origin was further analyzed by hierarchical clustering analysis (HCA). Results: The ruscogenin was successfully determined by HPLC-ELSD with a two-phase solvent system composed of methanol-water (88:12) at a flow rate 1.0 ml/min, column temperature maintained at 25°C, detector draft tube temperature at 42.2°C, nebulizer gas flow rate at 1.4 L/min, and the gain at 8. The result showed the good linearity of ruscogenin in the range of 40.20–804.00 μg/ml (R2 = 0.9996). Average of recovery was 101.3% (relative standard deviation = 1.59%). A significant difference of ruscogenin content was shown among 35 batches of Ophiopogenis Radix from different origin, varied from 0.0035% to 0.0240%. HCA based on the content of ruscogenin indicated that Ophiopogonis Radix in different origin was mainly divided into two clusters. Conclusion: This simple, rapid, low-cost, and reliable HPLC-ELSD method could be suitable for measurement of ruscogenin content rations and quality control of Ophiopogonis Radix. SUMMARY Ophiopogonis Radix is an important Traditional Chinese Medicine (TCM) to treat and prevent cardiovascular diseases and acute or chronic inflammation for thousands of years. Steroidal saponins were known as the dominant active components for their significant cardiovascular activity, and the most steroid sapogenin of them is

  5. The comparative pharmacokinetics of four bioactive ingredients after administration of Ramulus Cinnamomi-Radix Glycyrrhizae herb pair extract, Ramulus Cinnamomi extract and Radix Glycyrrhizae extract.

    PubMed

    Wang, Shengnan; Sun, Lijiao; Gu, Liqiang; Zhang, Yuanyuan; Zhao, Simin; Zhao, Long-Shan; Bi, Kai-Shun; Chen, Xiaohui

    2016-08-01

    Ramulus Cinnamomi (RC)-Radix Glycyrrhizae (RG) is a classic herb pair, which is commonly used as a fixed form to treat cardiovascular disease in the clinic. Our work aimed to compare the pharmacokinetic difference of cinnamic acid, liquiritin, isoliquiritigenin and glycyrrhetinic acid in rats after oral administration of the RC-RG herb pair extracts [Guizhigancao Decoction (GGD) and Lingguizhugan Decoction (LGZGD)] and the single RC or RG extract. A HPLC-MS method was developed and validated to study comparative pharmacokinetics. The pharmacokinetic parameters (Cmax , AUC, MRT) of four compounds between the RC-RG herb pair group and the single herb (RC or RG) group showed significant differences (p < 0.05). Compared with the single herb (RC or RG) group, higher peak concentration, slower elimination and larger exposure could be observed after giving the RC-RG herb-pair extracts. The pharmacokinetic differences might indicate the relativity of remedy in the RC-RG herb pair and provide scientific information for rational administration of the drug in the clinic. Copyright © 2016 John Wiley & Sons, Ltd. PMID:26694528

  6. [Isolation and preparation of an imidazole alkaloid from radix radix of Aconitum pendulum Busch by semi-preparative high-speed counter-current chromatography].

    PubMed

    Liu, Yongling; Chen, Tao; Chen, Chen; Zou, Denglang; Li, Yulin

    2014-05-01

    Aconitum pendulum Busch is rich C19 diterpenoid alkaloids, but there is no report of imidazole alkaloid in Aconitum pendulum Busch. In this study, an imidazole alkaloid named 1H-imidazole-2-carboxylic acid, butyl ester (ICABE) was successfully separated from Aconitum pendulum Busch with semi-preparative high-speed counter-current chromatography (HSCCC). The partition coefficient was measured by HPLC to select the solvent systems for ICABE separation by HSCCC. The separation was performed with a two-phase solvent system composed of n-hexane-chloroform-ethanol-water (10:1 : 13:2, v/v/v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase. It was operated at a flow rate of 1.8 mL/min. The apparatus was rotated at 850 r/min, and the detection wavelength was set at 230 nm. Under the selected conditions, a high efficiency separation of HSCCC was achieved, and 7.5 mg of ICABE was obtained from 100 mg of the crude sample of Aconitum pendulum in one-step separation within 350 min. The HPLC analysis showed that the purity of the compound was over 98%. The chemical structure was confirmed by UV, 1H-NMR and 13C-NMR. The established method is simple, highly efficient and suitable for large scale separation of ICABE from radix of Aconitum pendulum Busch. PMID:25185318

  7. Evaluation of the effects of Angelicae dahuricae radix on the morphology and viability of mesenchymal stem cells.

    PubMed

    Jeong, Su-Hyeon; Kim, Bo-Bae; Lee, Ji-Eun; Ko, Youngkyung; Park, Jun-Beom

    2015-07-01

    Angelicae dahuricae radix is a traditional herbal medicine used to treat various diseases in China and Korea, such as colds, headaches, rhinitis and psoriasis. Angelicae dahuricae radix has been used as an anti-inflammatory, analgesic, antipyretic and antioxidant remedy. This study was performed in order to evaluate the effects of the extracts of Angelicae dahuricae radix on the morphology and viability of mesenchymal stem cells derived from the gingiva. Mesenchymal stem cells derived from the gingiva were grown in the presence of Angelicae dahuricae radix at final concentrations that ranged from 0.001 to 100 µg/ml. The morphology of the cells was viewed under an inverted microscope, and the analysis of cell proliferation was performed with cell counting kit-8 (CCK-8) on days 1, 3 and 7. The cells in the control group had spindle-shaped, fibroblast-like morphology at days 1, 3 and 7 under optical microscopy. The shapes of the cells in 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix were similar to the shapes of the cells in the control group. The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10, and 100 µg/ml Angelicae dahuricae radix were 102.5 ± 0.6, 133.3 ± 9.6, 148.4 ± 20.5, 147.7 ± 12.6, 132.3 ± 27.7 and 101.1 ± 4.6%, respectively, when the CCK-8 result of the control group on day 1 was considered to be 100%. There was a marginal increase in cell proliferation at 0.1 and 1 µg/ml groups at day 1; however, this did not achieve statistical significance (P=0.052). The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix were 96.5 ± 1.3, 89.3 ± 0.9, 90.3 ± 3.0, 84.8 ± 12.2, 92.3 ± 4.5 and 86.8 ± 11.7%, respectively, when the CCK-8 result of the control group on day 3 was considered to be 100% (P>0.05). The relative values of the CCK-8 assays of 0.001, 0.01, 0.1, 1, 10 and 100 µg/ml Angelicae dahuricae radix day 7 were 94.9 ± 22.3, 102.8 ± 22.1, 127.4 ± 7.4, 130.4

  8. The high dose response and functional capability of the DT-702/Pd lithium fluoride thermoluminescent dosimeter.

    PubMed

    Lawlor, Tyler M; Talmadge, Molly D; Murray, Mark M; Nelson, Martin E; Mueller, Andrew C; Romanyukha, Alexander A; Fairchild, Gregory R; Grypp, Matthew D; Williams, Anthony S

    2015-05-01

    The United States Navy monitors the dose its radiation workers receive using the DT-702/PD thermoluminescent dosimeter, which consists of the Harshaw 8840 holder and the four-element Harshaw 8841 card. There were two main objectives of this research. In the first objective, the dosimeters were exposed to 100 Gy using electron and x-ray beams and found to respond approximately 30-40% lower than the delivered dose. No significant effect on the under-response was found when dose rate, radiation type, dosimeter position on the phantom, and dosimeter material were varied or when the card was irradiated while enclosed in its holder. Since the current naval policy is to remove from occupational use any thermoluminescent dosimeter with an accumulated deep dose equivalent of 0.05 Sv or greater, the functionality of the dosimeter was also investigated at deep dose equivalents of 0.05, 0.15, and 0.25 Sv using 60Co and 137Cs sources as the second main objective. All dosimeters were annealed following exposure and then exposed to 5.0 mSv from a 90Sr source. In all cases, the dosimeters responded within 3% of the delivered dose, indicating that the dosimeters remained functional as defined by naval dosimetry requirements. However, the anneal time required to clear the thermoluminescent dosimeter's reading was found to increase approximately as the cube root with the delivered dose. PMID:25811149

  9. Characterization of high-sensitivity metal oxide semiconductor field effect transistor dosimeters system and LiF:Mg,Cu,P thermoluminescence dosimeters for use in diagnostic radiology.

    PubMed

    Dong, S L; Chu, T C; Lan, G Y; Wu, T H; Lin, Y C; Lee, J S

    2002-12-01

    Monitoring radiation exposure during diagnostic radiographic procedures has recently become an area of interest. In recent years, the LiF:Mg,Cu,P thermoluminescence dosimeter (TLD-100H) and the highly sensitive metal oxide semiconductor field effect transistor (MOSFET) dosimeter were introduced as good candidates for entrance skin dose measurements in diagnostic radiology. In the present study, the TLD-100H and the MOSFET dosimeters were evaluated for sensitivity, linearity, energy, angular dependence, and post-exposure response. Our results indicate that the TLD-100H dosimeter has excellent linearity within diagnostic energy ranges and its sensitivity variations were under 3% at tube potentials from 40Vp to 125kVp. Good linearity was also observed with the MOSFET dosimeter, but in low-dose regions the values are less reliable and were found to be a function of the tube potentials. Both dosimeters also presented predictable angular dependence in this study. Our findings suggest that the TLD-100H dosimeter is more appropriate for low-dose diagnostic procedures such as chest and skull projections. The MOSFET dosimeter system is valuable for entrance skin dose measurement with lumbar spine projections and certain fluoroscopic procedures. PMID:12406633

  10. [Measurement of the Dose Rate Using Dosimeters in Interventional Radiology and Its Difficulty].

    PubMed

    Yoshida, Hidenori; Takahashi, Chiharu; Narita, Nobuhiro; Mizusawa, Yasuhiko; Sekiya, Masaru; Ohkubo, Masaki

    2016-01-01

    In equipment used for interventional radiology (IVR), automatic exposure control (AEC) is incorporated to obtain the X-ray output suitable for the treatment of targeted lesions. For the AEC, users select a region as the signal sensing region (measuring field, MF) in the flat panel detector; MFs with various sizes and shapes were pre-defined and prepared in the system. The aim of this study was to examine the change of measured dose rate with the selection of MFs, the type of dosimeters (the ionization chamber dosimeter and the semiconductor dosimeter), and the dosimeter placement relative to the direction of X-ray tube (from cathode to anode). The IVR equipment was Allura Xper FD20/10 (Philips Medical Systems), and six kinds of built-in MFs were used. It was found that dose rate measured by the ionization chamber dosimeter showed a variation of -2 mGy/min with the MFs and the ionization chamber dosimeter placement. The dose rate measured by the semiconductor dosimeter showed more variation than the ionization chamber dosimeter. The change of dose rate with the dosimeter placement would be caused by the MF overlapping the dosimeter which would affect the AEC (the X-ray output). Also, the change of dose rate with the dosimeter placement was considered to be related to the heel effect of the X-ray beam. When performing dose rate measurements, we should notice that the selection of MFs, the type of dosimeters, and the dosimeter placement would affect the measured values. PMID:26796935

  11. Fluorescence enhancement of radix angelica dahurica by binding to single silver sphere

    NASA Astrophysics Data System (ADS)

    Wang, Qing-Ru; Shi, Qiang; Li, Shu-Hong; Wang, Wen-Jun

    2015-05-01

    We present a theoretical study of the influence of a single silver sphere on the fluorescence of radix angelica dahurica, which is a kind of traditional Chinese medicine. The enhancement factors of the excitation and the relaxation processes are deduced. The excitation can be enhanced more than 100 times at 315 nm. The enhancement factor of the emission can reach up to 9 at a center wavelength of 400 nm. Project supported by the National Natural Science Foundation of China (Grant Nos. 61405085 and 61275147), the Research Fund for the Doctoral Program of Liaocheng University, China, the Key Project of Science and Technology of Shandong Province of China (Grant No. 2010GGX10127), and the Shandong Province Natural Science Foundation of China (Grant Nos. ZR2013EML006 and ZR2012AL11).

  12. Screening of direct thrombin inhibitors from Radix Salviae Miltiorrhizae by a peak fractionation approach.

    PubMed

    Lu, Jun; Song, Hui-Peng; Li, Ping; Zhou, Ping; Dong, Xin; Chen, Jun

    2015-05-10

    Thrombin plays a significant role in thromboembolic disease. In this work, a peak fractionation approach combined with an activity assay method was used to screen direct thrombin inhibitors from Radix Salviae Miltiorrhizae (RSM), a famous herbal remedy for the treatment of cardiovascular diseases in China. A total of 91 fractions were collected from the RSM extract, and 19 fractions out of them showed thrombin inhibitory effects with dose-effect relationship. Among them, three compounds were unambiguously identified as 15, 16-dihydrotanshinone I, cryptotanshinone and tanshinone IIA with IC50 values of 29.39, 81.11 and 66.60μM, respectively. The three compounds were reported with direct thrombin inhibition activities for the first time and their ligand-thrombin interactions were explored by a molecular docking research. These results may contribute to explain the medical benefit of RSM for the prevention and treatment of cardiovascular diseases. PMID:25819728

  13. New sintered thermoluminescent dosimeters for personnel and environmental dosimetry.

    PubMed

    Prokic, M S

    1982-06-01

    We discuss the development of an original method preparing thermoluminescent dosimeters using magnesium borate and calcium sulfate materials activated with rare earths. This method is based upon the effect of sensitized thermoluminescent emission of basic TLD phosphors as well as on the method for producing these in solid form. Our technique resulted in unique TLD's in the form of sintered thermoluminescent dosimeters. For one of these, MgB4O7:RE+, the thermoluminescent response is up to five times more sensitive than non-sensitized magnesium borate thermoluminescent material. The other TLD, CaSO4:RE+, has dosimetric characteristics which stay unchanged and are equivalent with characteristics of the well-known calcium sulfate TLD phosphors. These new types of sintered TLD's are highly promising for personnel and environmental dosimetry. PMID:7107292

  14. A genipin-gelatin gel dosimeter for radiation processing

    NASA Astrophysics Data System (ADS)

    Davies, J. B.; Bosi, S. G.; Baldock, C.

    2012-08-01

    Genipin, a fruit extract from Gardenia jasminoides Ellis, forms cross-links in solutions of gelatin, to form a blue hydrogel that bleaches quantitatively upon irradiation and the colour change can be measured with a spectrophotometer. With the addition of sulphuric acid this dosimeter is sufficiently sensitive for quality assurance of radiotherapy level dosimetry. Without sulphuric acid the gel has a reduced sensitivity and responds linearly with dose between 100 and 1000 Gy, making it potentially useful as a dosimeter for radiation processing applications such as the phytosanitary irradiation treatment of food. We investigated the dose response characteristics of this new formulation and found that the darker gels are more sensitive to dose and have a reduced uncertainty.

  15. Radiochromic leuko dye real time dosimeter, one way optical waveguide

    SciTech Connect

    Kronenberg, S.

    1982-11-15

    This invention relates generally to nuclear radiation dosimetry, and more particularly to a radiochromic leuko dye dosimeter constructed and arranged to measure absorbed radiation doses, such as gamma rays, X-rays and fast neutrons, in real time; viz., as the dose is being delivered. A radiochromic leuko dye dosimeter includes a plastic tube containing a solution of a radiochromic dye which is sensitive to ionizing radiation, one end of the tube being closed by a reflective surface, the opposite end of the tube being closed by a transparent plug to form a one-way optical waveguide. Light enters the tube through the transparent end thereof and is reflected back and exists through the transparent end. The intensity of the existing light is measured to determine radiation induced absorption of the leuko dye.

  16. A new electronic neutron dosimeter (END) for reliable personal dosimetry

    NASA Astrophysics Data System (ADS)

    Ing, H.; Cousins, T.; Andrews, H. R.; Machrafi, R.; Voevodskiy, A.; Kovaltchouk, V.; Clifford, E. T. H.; Robins, M.; Larsson, C.; Hugron, R.; Brown, J.

    2008-04-01

    Tests of existing electronic neutron dosimeters by military and civilian groups have revealed significant performance limitations. To meet the operational requirements of emergency response personnel to a radiological/nuclear incident as well as those in the nuclear industry, a new END has been developed. It is patterned after a unique commercial neutron spectral dosemeter known as the N-probe. It uses a pair of small special scintillators on tiny photomultiplier tubes. Special electronics were designed to minimize power consumption to allow for weeks of operation on a single charge. The size, performance, and data analysis for the END have been designed to meet/exceed international standards for electronic neutron dosimeters. Results obtained with the END prototype are presented.

  17. Laser CT evaluation on normoxic PAGAT gel dosimeter

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  18. Polygalasaponin XXXII, a triterpenoid saponin from Polygalae Radix, attenuates scopolamine-induced cognitive impairments in mice

    PubMed Central

    Zhou, Heng; Xue, Wei; Chu, Shi-feng; Wang, Zhen-zhen; Li, Chuang-jun; Jiang, Yi-na; Luo, Lin-ming; Luo, Piao; Li, Gang; Zhang, Dong-ming; Chen, Nai-hong

    2016-01-01

    Aim: Recent studies show that the extract of a Chinese herb Polygalae Radix exerts cognition-enhancing actions in rats and humans. The aim of this study was to characterize the pharmacological profiles of active compounds extracted from Polygalae Radix. Methods: Two fractions P3 and P6 and two compounds PTM-15 and polygalasaponin XXXII (PGS32) were prepared. Neuroprotective effects were evaluated in primary cortical neurons exposed to high concentration glutamate, serum deficiency or H2O2. Anti-dementia actions were assessed in scopolamine-induced amnesia in mice using step-through avoidance tests and channel water maze tests. After conducting the channel water maze tests, TrkB phosphorylation in mouse hippocampus was detected using Western blotting. Long-term potentiation (LTP) was induced in the dentate gyrus in adult rats; PGS32 (5 μL 400 μmol/L) was injected into the lateral cerebral ventricle 20 min after high frequency stimulation (HFS). Results: Compared to the fraction P6, the fraction P3 showed more prominent neuroprotective effects in vitro and cognition-enhancing effects in scopolamine-induced amnesia in mice. One active compound PGS32 in the fraction P3 exerted potent cognition-enhancing action: oral administration of PGS32 (0.125 mg·kg−1·d−1) for 19 days abolished scopolamine-induced memory impairment in mice. Furthermore, PGS32 (0.5 and 2 mg·kg−1·d−1) significantly stimulated the phosphorylation of TrkB in the hippocampus. Intracerebroventricular injection of PGS32 significantly enhanced HFS-induced LTP in the dentate gyrus of rats. Conclusion: PGS32 attenuates scopolamine-induced cognitive impairments in mice, suggesting that it has a potential for the treatment of cognitive dysfunction and dementia. PMID:27180981

  19. Mechanism of angiogenic effects of saponin from ginseng Radix rubra in human umbilical vein endothelial cells.

    PubMed Central

    Morisaki, N.; Watanabe, S.; Tezuka, M.; Zenibayashi, M.; Shiina, R.; Koyama, N.; Kanzaki, T.; Saito, Y.

    1995-01-01

    1. The effects of saponin from Ginseng Radix rubra on angiogenesis (tube formation) and its key steps (protease secretion, proliferation and migration) in human umbilical vein endothelial cells (HUVEC) were examined to elucidate the mechanism of the tissue repairing effects of Ginseng Radix rubra. The effect on a wound healing model was also studied. 2. Tube formation was measured by an in vitro system. The activity and immunoreactivity of tissue-type plasminogen activator (tPA) as a protease for angiogenesis and the immunoreactivity of its inhibitor, plasminogen activator inhibitor-1 (PAI-1), were measured in conditioned medium of HUVEC stimulated for 24 h with saponin. Cell proliferation was measured by counting the cell numbers at 2-7 days after seeding. Migration was measured by Boyden's chamber method. The effect on wound healing was studied in the skin of diabetic rats. 3. Saponin at 10-100 micrograms ml-1 significantly stimulated tube formation by HUVEC in a dose-dependent manner. Saponin in a similar concentration-range increased the secretion of tPA from HUVEC as estimated by immunoreactivity and enzyme activity. On the other hand, PAI-1 immunoreactivity was slightly increased at 10 micrograms ml-1 of saponin, but then was significantly decreased at 50 and 100 micrograms ml-1. Cell proliferation was only slightly enhanced by 1-100 micrograms ml-1 of saponin, but migration was significantly enhanced by 10-100 micrograms ml-1 in a dose-dependent manner. Moreover, saponin stimulated wound healing with enhanced angiogenesis in vivo.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1 Figure 8 PMID:7582543

  20. Anti-hyperglycemic effect of fangchinoline isolated from Stephania tetrandra Radix in streptozotocin-diabetic mice.

    PubMed

    Tsutsumi, Taiki; Kobayashi, Shinjiro; Liu, Yuan Ying; Kontani, Hitoshi

    2003-03-01

    Kampo medicine, Stephania tetrandra Radix (Stephania) in Boi-ogi-to increases the blood insulin level and falls the blood glucose level in streptozotocin (STZ)-diabetic ddY mice. These actions of Stephania are potentiated by Astragalus membranaceus Bunge Radix (Astragali) in Boi-ogi-to (Liu et al., J. Traditional Med., 17, 253-260, 2000). In the present study, actions of bis-benzylisoquinoline alkaloids isolated from Stephania were investigated in the hyperglycemia of STZ-diabetic mice. A main bis-benzylisoquinoline alkaloid, fangchinoline (0.3-3 mg/kg) significantly fell the blood glucose level of the diabetic mice in a dose-dependent manner. The effect of fangchinoline was 3.9-fold greater than that of water extract of Stephania. However, another main compound, tetrandrine (1-100 mg/kg) did not have any effect. The water extract of Astragali did not affect singly but potentiated the anti-hyperglycemic action of fangchinoline (0.3 mg/kg). Out of used compounds (1 mg/kg) isolated from Stephania, fangchinoline, fangchinoline 2'-N-alpha-oxide and 2'-N-norfangchinoline, which are substituted with 7-hydroxy side chain for 7-O-methyl side chain, decreased to near 50% of high blood glucose level. In addition, tetrandrine 2'-N-beta-oxide, tetrandrine 2'-N-alpha-oxide, tetrandrine 2-N-beta-oxide, fangchinoline 2'-N-alpha-oxide, which are added to 2- or 2'-N-oxide side chain, also decreased to near 50% of the high blood glucose level. In conclusion, fangchinoline but not tetrandrine from Stephania shows the anti-hyperglycemic action in the STZ-diabetic mice. The demethylation of 7-O-position and/or addition of 2- or 2'-N-oxide side chain in bis-benzylisoquinoline compounds in Stephania have a role for the induction of the anti-hyperglycemic actions. PMID:12612439

  1. Low-cost commercial glass beads as dosimeters in radiotherapy

    NASA Astrophysics Data System (ADS)

    Jafari, S. M.; Bradley, D. A.; Gouldstone, C. A.; Sharpe, P. H. G.; Alalawi, A.; Jordan, T. J.; Clark, C. H.; Nisbet, A.; Spyrou, N. M.

    2014-04-01

    Recent developments in advanced radiotherapy techniques using small field photon beams, require small detectors to determine the delivered dose in steep dose gradient fields. Commercially available glass jewellery beads exhibit thermoluminescent properties and have the potential to be used as dosimeters in radiotherapy due to their small size (<5 mm), low cost, reusability and inert nature. This study investigated the dosimetric characteristics of glass beads. The beads were irradiated by 6 MV photons using a medical linear-accelerator and 60Co gamma rays over doses ranging from 1 to 2500 cGy. A thermoluminescence (TL) system and an electron paramagnetic resonance (EPR) system were employed for read out. Both the TL and EPR studies demonstrated a radiation-induced signal, the sensitivity of which varied with bead colour. White coloured beads proved to be the most sensitive for both systems. The smallest and therefore least sensitive bead sizes allowed measurement of doses of 1 cGy using the TL system while that for the EPR system was approximately 1000 cGy. The fading rate was found to be 10% 30 days after irradiation with both readout systems. The dose response is linear with measured dose over the dose range 1 to 2500 cGy, with an R2 correlation coefficient of greater than 0.999. The batch-to-batch reproducibility of a set of dosimeters after a single irradiation was found to be 3% (1 SD). The reproducibility of individual dosimeters was found to be 1.7%. No measurable angular dependence was found (results agreed within 1%). Dose rate response was found to agree within 1% for dose rates of 100 to 600 cGy/min. These results demonstrate the potential use of glass beads as TL dosimeters over the dose range commonly applied in radiotherapy.

  2. An optical dosimeter for monitoring heavy metal ions in water

    NASA Astrophysics Data System (ADS)

    Mignani, Anna G.; Regan, Fiona; Leamy, D.; Mencaglia, A. A.; Ciaccheri, L.

    2005-05-01

    This work presents an optochemical dosimeter for determining and discriminating nickel, copper, and cobalt ions in water that can be used as an early warning system for water pollution. An inexpensive fiber optic spectrophotometer monitors the sensor's spectral behavior under exposure to water solutions of heavy metal ions in the 1-10 mg/l concentration range. The Principal Component Analysis (PCA) method quantitatively determines the heavy metals and discriminates their type and combination.

  3. Method for preparing dosimeter for measuring skin dose

    DOEpatents

    Jones, Donald E.; Parker, DeRay; Boren, Paul R.

    1982-01-01

    A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with neutron-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

  4. Dosimeter for measuring skin dose and more deeply penetrating radiation

    DOEpatents

    Jones, Donald E.; Parker, DeRay; Boren, Paul R.

    1981-01-01

    A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with netruon-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

  5. Response of ionization chamber based pocket dosimeter to beta radiation.

    PubMed

    Kumar, Munish; Gupta, Anil; Pradhan, S M; Bakshi, A K; Chougaonkar, M P; Babu, D A R

    2013-12-01

    Quantitative estimate of the response of ionization chamber based pocket dosimeters (DRDs) to various beta sources was performed. It has been established that the ionization chamber based pocket dosimeters do not respond to beta particles having energy (Emax)<1 MeV and same was verified using (147)Pm, (85)Kr and (204)Tl beta sources. However, for beta particles having energy >1 MeV, the DRDs exhibit measureable response and the values are ~8%, ~14% and ~27% per mSv for natural uranium, (90)Sr/(90)Y and (106)Ru/(106)Rh beta sources respectively. As the energy of the beta particles increases, the response also increases. The response of DRDs to beta particles having energy>1 MeV arises due to the fact that the thickness of the chamber walls is less than the maximum range of beta particles. This may also be one of the reasons for disparity between doses measured with passive/legal dosimeters (TLDs) and DRDs in those situations in which radiation workers are exposed to mixed field of gamma photons and beta particles especially at uranium processing plants, nuclear (power and research) reactors, waste management facilities and fuel reprocessing plants etc. The paper provides the reason (technical) for disparity between the doses recorded by TLDs and DRDs in mixed field of photons and beta particles. PMID:23978508

  6. Radiation measured for MATROSHKA-1 experiment with passive dosimeters

    NASA Astrophysics Data System (ADS)

    Zhou, D.; Semones, E.; O'Sullivan, D.; Zapp, N.; Weyland, M.; Reitz, G.; Berger, T.; Benton, E. R.

    2010-01-01

    The radiation field in low Earth orbit (LEO) and deep space is complicated. The radiation impact on astronauts depends strongly on the particles' linear energy transfer (LET) and is dominated by high LET radiation. Radiation risk is a key concern for human space flight and can be estimated with radiation LET spectra measured for the different organs of an astronaut phantom. At present the best passive personal dosimeters used for astronauts are thermoluminescence dosimeters (TLDs) and optically stimulated luminescence dosimeters (OSLDs) for low LET and CR-39 plastic nuclear track detectors (PNTDs) for high LET. CR-39 PNTDs, TLDs and OSLDs were used for the MATROSHKA-1 experiment to measure radiation experienced by astronauts outside the international space station (ISS). LET spectra and radiation field quantities (differential and integral fluence, absorbed dose and dose equivalent) were measured for the different organs and skin locations of the MAROSHKA phantom using CR-39 PNTDs and TLDs. The spectra and results can be used to determine the radiation quantities for astronaut's extra vehicular activity (EVA) and for the further in-depth study of the radiation risk for astronauts. Sensitivity fading of CR-39 detectors was observed for the MATROSHKA experiment and a practical method was developed to correct it. This paper presents the radiation LET spectra measured with CR-39 PNTDs and the total radiation quantities combined from results measured with CR-39 PNTDs and TLDs.

  7. NOTE: Visible absorption spectra of radiation exposed SIRAD dosimeters

    NASA Astrophysics Data System (ADS)

    Butson, Martin J.; Cheung, Tsang; Yu, Peter K. N.

    2006-12-01

    SIRAD badge dosimeters are a new type of personal dosimeter designed to measure radiation exposure up to 200 R and give a visual qualitative measurement of exposure. This is performed using the active dosimeter window, which contains a radiochromic material amalgamated in the badge assembly. When irradiated, the badges active window turns blue, which can be matched against the given colour chart for a qualitative assessment of the exposure received. Measurements have been performed to analyse the absorption spectra of the active window, and results show that the window automatically turns a blue colour upon irradiation and produces two peaks in the absorption spectra located at 617 nm and 567 nm. When analysed with a common computer desktop scanner, the optical density response of the film to radiation exposure is non-linear but reproducible. The net OD of the film was 0.21 at 50 R exposure and 0.31 at 200 R exposure when irradiated with a 6 MV x-ray energy beam. When compared to the calibration colour strips at 6 MV x-ray energy the film's OD response matches relatively well within 3.5%. An approximate 8% reduction in measured OD to exposure was seen for 250 kVp x-rays compared to 6 MV x-rays. The film provides an adequate measurement and visually qualitative assessment of radiation exposure for levels in the range of 0 to 200 R.

  8. Real-time dosimeter targeted to nuclear applications

    NASA Astrophysics Data System (ADS)

    Correia, Alexandre; Rosa, Carla C.; Santos, Pedro M. P.; Falcão, António N.; Lorentz, Katharina

    2014-08-01

    An intrinsic fiber optic dosimeter (FOD) targeted to nuclear applications is presented. The proposed real-time dosimeter provides dose information based on the historic record over time of the effects of ionizing radiation on single- and multimode pure silica fibers, and also on PMMA plastic fibers. The effect of 60Co gamma irradiation on optical links based on silica and plastic fibers were assessed, considering thermal environment effects over a wide range of variation of the operating parameters. Cerenkov radiation and radiation-induced absorption effects were in focus. The corresponding distortion and spectral transmission degradation were evaluated over wide range of the operating parameters. Radiation induced attenuation (RIA) has shown a spectral band dependent behaviour up to 840 Gy dose levels. The performance of different fibers was assessed against the performance of non-irradiated fibers. From the measurements of dose rate and total dose imparted by ionizing radiation in the fibers we verified that fibers with radiation resistance issues showed wavelength-dependent radiation sensitivity increasing with dose rate. Upon evaluation of correlations between the total dose, the induced loss at various dose rates and different wavelengths, it was concluded that intrinsic fiber dosimeters can be used for dose rates in the range 4 - 28 Gy/min., typical of severe radiation environments.

  9. The Assessment of Effective Dose Equivalent Using Personnel Dosimeters

    NASA Astrophysics Data System (ADS)

    Xu, Xie

    From January 1994, U.S. nuclear plants must develop a technically rigorous approach for determining the effective dose equivalent for their work forces. This dissertation explains concepts associated with effective dose equivalent and describes how to assess effective dose equivalent by using conventional personnel dosimetry measurements. A Monte Carlo computer code, MCNP, was used to calculate photon transport through a model of the human body. Published mathematical phantoms of the human adult male and female were used to simulate irradiation from a variety of external radiation sources in order to calculate organ and tissue doses, as well as effective dose equivalent using weighting factors from ICRP Publication 26. The radiation sources considered were broad parallel photon beams incident on the body from 91 different angles and isotropic point sources located at 234 different locations in contact with or near the body. Monoenergetic photons of 0.08, 0.3, and 1.0 MeV were considered for both sources. Personnel dosimeters were simulated on the surface of the body and exposed to with the same sources. From these data, the influence of dosimeter position on dosimeter response was investigated. Different algorithms for assessing effective dose equivalent from personnel dosimeter responses were proposed and evaluated. The results indicate that the current single-badge approach is satisfactory for most common exposure situations encountered in nuclear plants, but additional conversion factors may be used when more accurate results become desirable. For uncommon exposures involving source situated at the back of the body or source located overhead, the current approach of using multi-badges and assigning the highest dose is overly conservative and unnecessarily expensive. For these uncommon exposures, a new algorithm, based on two dosimeters, one on the front of the body and another one on the back of the body, has been shown to yield conservative assessment of

  10. A basic study of some normoxic polymer gel dosimeters.

    PubMed

    De Deene, Y; Hurley, C; Venning, A; Vergote, K; Mather, M; Healy, B J; Baldock, C

    2002-10-01

    Polymer gel dosimeters offer a wide range of potential applications in the three-dimensional verification of complex dose distribution such as in intensity-modulated radiotherapy (IMRT). Until now, however, polymer gel dosimeters have not been widely used in the clinic. One of the reasons is that they are difficult to manufacture. As the polymerization in polymer gels is inhibited by oxygen, all free oxygen has to be removed from the gels. For several years this was achieved by bubbling nitrogen through the gel solutions and by filling the phantoms in a glove box that is perfused with nitrogen. Recently another gel formulation was proposed in which oxygen is bound in a metallo-organic complex thus removing the problem of oxygen inhibition. The proposed gel consists of methacrylic acid, gelatin, ascorbic acid, hydroquinone and copper(II)sulphate and is given the acronym MAGIC gel dosimeter. These gels are fabricated under normal atmospheric conditions and are therefore called 'normoxic' gel dosimeters. In this study, a chemical analysis on the MAGIC gel was performed. The composition of the gel was varied and its radiation response was evaluated. The role of different chemicals and the reaction kinetics are discussed. It was found that ascorbic acid alone was able to bind the oxygen and can thus be used as an anti-oxidant in a polymer gel dosimeter. It was also found that the anti-oxidants N-acetyl-cysteine and tetrakis(hydroxymethyl)phosphonium were effective in scavenging the oxygen. However, the rate of oxygen scavenging is dependent on the anti-oxidant and its concentration with tetrakis(hydroxymethyl)phosphonium being the most reactive anti-oxidants. Potentiometric oxygen measurements in solution provide an easy way to get a first impression on the rate of oxygen scavenging. It is shown that cupper(II)sulphate operates as a catalyst in the oxidation of ascorbic acid. We, therefore, propose some new normoxic gel formulations that have a less complicated chemical

  11. Investigation of radiological properties and water equivalency of PRESAGE dosimeters

    SciTech Connect

    Gorjiara, Tina; Hill, Robin; Kuncic, Zdenka; Adamovics, John; Bosi, Stephen; Kim, Jung-Ha; Baldock, Clive

    2011-04-15

    Purpose: PRESAGE is a dosimeter made of polyurethane, which is suitable for 3D dosimetry in modern radiation treatment techniques. Since an ideal dosimeter is radiologically water equivalent, the authors investigated water equivalency and the radiological properties of three different PRESAGE formulations that differ primarily in their elemental compositions. Two of the formulations are new and have lower halogen content than the original formulation. Methods: The radiological water equivalence was assessed by comparing the densities, interaction probabilities, and radiation dosimetry properties of the three different PRESAGE formulations to the corresponding values for water. The relative depth doses were calculated using Monte Carlo methods for 50, 100, 200, and 350 kVp and 6 MV x-ray beams. Results: The mass densities of the three PRESAGE formulations varied from 5.3% higher than that of water to as much as 10% higher than that of water for the original formulation. The probability of photoelectric absorption in the three different PRESAGE formulations varied from 2.2 times greater than that of water for the new formulations to 3.5 times greater than that of water for the original formulation. The mass attenuation coefficient for the three formulations is 12%-50% higher than the value for water. These differences occur over an energy range (10-100 keV) in which the photoelectric effect is the dominant interaction. The collision mass stopping powers of the relatively lower halogen-containing PRESAGE formulations also exhibit marginally better water equivalency than the original higher halogen-containing PRESAGE formulation. Furthermore, the depth dose curves for the lower halogen-containing PRESAGE formulations are slightly closer to that of water for a 6 MV beam. In the kilovoltage energy range, the depth dose curves for the lower halogen-containing PRESAGE formulations are in better agreement with water than the original PRESAGE formulation. Conclusions: Based

  12. Development of an operational multicomponent personnel neutron dosimeter/spectrometer DOSPEC

    SciTech Connect

    Griffith, R.V.; McMahon, T.A.

    1983-10-26

    A multicomponent dosimeter has been developed that uses an albedo detector to provide the measurement of low energy neutrons and as a screening element. It also contains track detector components, CR-39 and polycarbonate, which are only processed if the TLD indicates there has been an exposure to neutrons. Since the three components have significantly different energy responses, the dosimeter can act as a crude spectrometer. This report describes the dosimeter and briefly summarizes its use experience. 10 refs., 2 figs., 2 tabs.

  13. Fat Grafting to the Forehead/Glabella/Radix Complex and Pyriform Aperture: Aesthetic and Anti-Aging Implications

    PubMed Central

    Nikfarjam, Jeremy S.

    2015-01-01

    Background: Optimal aesthetic outcomes from rhinoplasty are heavily influenced by structures adjacent to the nose. Although the importance of the chin has been emphasized since the inception of rhinoplasty, little attention has been given to the forehead. The forehead/glabella/radix complex represents a vital triad in rhinoplasty, from which the nasofrontal angle is derived. In the present study, the authors sought to determine whether fat grafting to the forehead/glabella/radix complex and pyriform aperture can favorably impact the nasofrontal and nasolabial angles, respectively. Methods: The authors reviewed pre- and postoperative images (obtained by an independent professional photographer) of patients who underwent autologous fat grafting to the forehead/glabella/radix region and the pyriform aperture, with or without concurrent rhinoplasty. Nasofrontal and nasolabial angles were measured on lateral images. Mean pre- and postoperative values were calculated and compared. A Wilcoxon rank-sum test was used for statistical analysis. Results: Twenty-six patients underwent fat grafting alone (FG group; mean follow-up, 3.3 years), and 19 had fat grafting plus rhinoplasty (FG + R group; mean follow-up, 5.2 years). The mean nasofrontal angle in the FG group decreased by 2.0° (P = 0.005), and the mean nasolabial angle increased by 2.3° (P = 0.006). The mean nasofrontal angle in the FG + R group decreased by 2.0° (P = 0.011), and the mean nasolabial angle increased by 6.0° (P = 0.026). Conclusions: Autologous fat grafting to the forehead/glabella/radix complex and pyriform aperture is a reliable method to favorably influence the nasofrontal and nasolabial angles, respectively. Such treatment optimizes the interplay between the nose and the adjacent facial features, enhancing overall aesthetics. PMID:26495213

  14. Chemical constituents of Chinese natural medicine, morindae radix, the dried roots of morinda officinalis how.: structures of morindolide and morofficinaloside.

    PubMed

    Yoshikawa, M; Yamaguchi, S; Nishisaka, H; Yamahara, J; Murakami, N

    1995-09-01

    A new iridoid lactone, morindolide, and a new iridoid glucoside, morofficinaloside, have been isolated from a Chinese natural medicine, Morindae Radix, the dried root of Morinda officinalis How. together with a number of known compounds: five anthraquinones, four iridoid glucosides, a monoterpene glycoside, two sterols, an ursane-type triterpene, and a lactone compound. The chemical structures of the new compounds were determined on the basis of chemical and physicochemical evidence. PMID:7586069

  15. Performance evaluation of diagnostic radiology dosimeters in clinical and calibration x-ray beams.

    PubMed

    Hourdakis, Costantine John; Boziari, Argyro; Manetou, Aggeliki

    2010-05-01

    Diagnostic radiology dosimeters should comply with International Electrotechnical Commission (IEC) 61674 standard in order to perform measurements with sufficient accuracy and reliability. The calibration of a dosimeter is performed under, and pertains to, reference conditions. However, in most cases, dosimeters are used for clinical measurements under non-reference conditions. The performance, in terms of accuracy of dose measurements, of six commercial diagnostic radiology dosimeters was tested at reference calibration and at clinical non-reference conditions. The results showed that all dosimeters being tested exhibited limits of variation within the +/-5% IEC limits. Depending on the detector's physical and operational properties, the dosimeters' energy dependence of response values varied from -4.7% to +4.2%. To address this variation of response, calibration at three radiation qualities (RQR 3, RQR 5, and RQR 9), at least, is recommended. Different irradiation conditions such as air kerma rate, x-ray tube design, x-ray system, and dosimeter operational modes affect the dosimeters' response by less than 3%. A dosimeter that complies with IEC standards and operates according to its specifications could be used at typical clinical irradiation conditions taking into account only corrections for the energy dependence of response. In this case, the error in dose accuracy is expected to be less than 3%. PMID:20386200

  16. The radix nasi island flap: a versatile musculocutaneous flap for defects of the eyelids, nose, and malar region.

    PubMed

    Seyhan, Tamer

    2009-03-01

    A versatile musculocutan flap from the radix nasi region, the radix nasi island flap, is described. The flap has an axial blood supply derived from the dorsal nasal branch of the ophthalmic artery which is anastomosed to the terminal branch of the facial artery. The flap includes the skin, subcutaneous tissue, and procerus muscle. Ten patients, aged 50 to 86 years, have been reconstructed with this flap for defects in the nose (in 4 cases), midface (in 4 cases) and lower eyelids (in 2 cases). The mean flap size was 17 x 23 mm (range: 15 x 20 to 20 x 27 mm). All flaps fully survived. Additional complications and morbidity were not observed. The donor sites were closed a primarily closure in all cases. Follow-up ranged from 3 to 12 months (mean: 8.2 months). The radix nasi flap is a safe flap, has minimal donor site morbidity, and is especially suited for nasal and midface reconstruction in terms of attaining a suitable color and thickness. PMID:19305249

  17. Novel characterization of Radix Angelicae Dahuricae before and after the sulfur-fumigation process by combining high performance liquid chromatographic fingerprint and multi-ingredients determination

    PubMed Central

    Liu, Xiao; Liu, Jingjing; Cai, Hao; Li, Songlin; Ma, Xiaoqing; Lou, Yajing; Qin, Kunming; Guan, Hongyue; Cai, Baochang

    2014-01-01

    Background: Harmful sulfur-fumigation processing method is abused during Radix Angelicae Dahuricae preparation. However, the analytical technique characterizing Radix Angelicae Dahuricae before and after the sulfur-fumigation process is absent. Materials and Methods: The high performance liquid chromatography (HPLC) technique was adopted to develop methods combining finger-print analysis and multi-ingredients simultaneous determination for quality evaluation of Radix Angelicae Dahuricae before and after the sulfur-fumigation process. The chromatographic fingerprint method was established for qualitative analysis coupled with statistical cluster analysis basing on Euclidean distance. Additionally, a determination method was developed for quantitative analysis, which was able to assay the concentrations of the major coumarins including imperatorin, isoimperatorin, xanthotoxin, xanthotoxol, isoimpinellin, oxypeucedanin, and bergapten in Radix Angelicae Dahuricae simultaneously. The separations of the two methods were both achieved on a Hypersil octadecylsilyl C18 column (250 mm × 4.6 mm, 5 μm) at 35°C under different strategic gradient elution programs. The detection wavelength was set at 254 nm all the time. Method validation data indicated that the methods were both reliable and applicable. They were then used to assay different Radix Angelicae Dahuricae samples collected from good agricultural practice (GAP) bases and local herbal markets. Results: The successful application demonstrated that the combination of HPLC fingerprint and simultaneous quantification of multi-ingredients offers an efficient approach for quality evaluation of Radix Angelicae Dahuricae before and after the sulfur-fumigation process. Conclusion: In order to discriminate Radix Angelicae Dahuricae before and after the sulfur-fumigation process, oxypeucedanin, and xanthotoxol were the most sensitive biomarkers and should be determined. PMID:25210323

  18. Percutaneous Pedicle Screw Fixation with Polymethylmethacrylate Augmentation for the Treatment of Thoracolumbar Intravertebral Pseudoarthrosis Associated with Kummell's Osteonecrosis

    PubMed Central

    2016-01-01

    Purpose. The purpose of our study is to evaluate the therapeutic efficacy of short-segment percutaneous pedicle screw fixation with polymethylmethacrylate (PMMA) augmentation for the treatment of osteoporotic thoracolumbar compression fracture with osteonecrosis. Methods. Osteoporotic thoracolumbar compression fractures with avascular necrosis were treated by short-segment PPF with PMMA augmentation. Eighteen were followed up for more than 2 years. The kyphotic angle, compression ratio, visual analog scale (VAS) score for back pain, and the Oswestry Disability Index (ODI) were analyzed. In addition, radiologic and clinical parameters of PPF group were compared with percutaneous vertebroplasty (PVP) group. Results. Vertebral height and kyphotic angle of the compressed vertebral bodies were significantly corrected after the operation (P < 0.05). Further, restored vertebral height was maintained during the 2 or more years of postoperative follow-up. Compared to the PVP group the postoperative compression ratio and kyphotic angle were significantly lower in the PPF group (P < 0.05). The postoperative ODI and VAS of the PVP group were significantly higher than the PPF (P < 0.05). Conclusions. According to our results, short-segment PPF with PMMA augmentation may be an effective minimally invasive treatment for osteoporosis in cases of osteoporotic vertebral compression fractures with Kummell's osteonecrosis. PMID:27595101

  19. A rapid, flexible method for incorporating controlled antibiotic release into porous polymethylmethacrylate space maintainers for craniofacial reconstruction.

    PubMed

    Mountziaris, P M; Shah, S R; Lam, J; Bennett, G N; Mikos, A G

    2016-01-01

    Severe injuries in the craniofacial complex, resulting from trauma or pathology, present several challenges to functional and aesthetic reconstruction. The anatomy and position of the craniofacial region make it vulnerable to injury and subsequent local infection due to external bacteria as well as those from neighbouring structures like the sinuses, nasal passages, and mouth. Porous polymethylmethacrylate (PMMA) "space maintainers" have proven useful in staged craniofacial reconstruction by promoting healing of overlying soft tissue prior to reconstruction of craniofacial bones. We describe herein a method by which the porosity of a prefabricated porous PMMA space maintainer, generated by porogen leaching, can be loaded with a thermogelling copolymer-based drug delivery system. Porogen leaching, space maintainer prewetting, and thermogel loading all significantly affected the loading of a model antibiotic, colistin. Weeks-long release of antibiotic at clinically relevant levels was achieved with several formulations. In vitro assays confirmed that the released colistin maintained its antibiotic activity against several bacterial targets. Our results suggest that this method is a valuable tool in the development of novel therapeutic approaches for the treatment of severe complex, infected craniofacial injuries. PMID:26340063

  20. Highly efficient chromium(VI) adsorption with nanofibrous filter paper prepared through electrospinning chitosan/polymethylmethacrylate composite.

    PubMed

    Li, Zhengyang; Li, Tingting; An, Libao; Fu, Pengfei; Gao, Cangjian; Zhang, Zhiming

    2016-02-10

    Chitosan/polymethylmethacrylate (PMMA) composite nanofibrous membrane was prepared by electrospinning technique with a single solvent system. Characterization with Fourier transformation infrared spectroscopy (FT-IR) indicated that there was weak interaction (such as hydrogen bonds) between PMMA and chitosan. Scanning electron microscopy (SEM) measurements illustrated that the average diameter of the composite nanofibers decreased as the chitosan content was increased, while the number of nano/micrometer sized beads increased in the membrane. The composite nanofibrous membrane with chitosan:PMMA ratio of 0.3:1.0 exhibited a maximum adsorption capacity (67.0 mg g(-1)) of Cr(VI) in static adsorption, which was nearly three times higher than that of chitosan powder (22.9 mg g(-1)). The adsorption capacity of Cr(VI) via filtration became even higher, where the maximum value was 92.5 mg g(-1) at pH 3.0. Notably, most of Cr(VI) has been removed after the first filtration at all pH values (2.0-6.0) investigated in this report. The adsorption capacity of the composite nanofibrous membrane decreased slightly (17.1%) after three filtration cycles even with the solution of pH 2.0, which shall be attributed to the enhanced mechanical strength and acid fastness of the composite membrane. X-ray photoelectron spectroscopy (XPS) analysis indicated that amino groups played an important role in the adsorption of Cr(VI). PMID:26686112

  1. The double polymethylmethacrylate filter (DELETE system) in the removal of light chains in chronic dialysis patients with multiple myeloma.

    PubMed

    Santoro, Antonio; Grazia, Michele; Mancini, Elena

    2013-01-01

    Multiple myeloma (MM) is still one of the most common haematological diseases and is associated with a poor prognosis. It is frequently worsened by acute kidney failure that, in turn, aggravates the risk of death. In the past few years, the idea has made headway that the removal of free light chains (FLC) by means of extracorporeal blood purification systems may facilitate the recovery of renal function. Up to now, many different extracorporeal techniques have been put forward in FLC removal, such as plasma exchange, dialysis with super-flux filters, and adsorption by means of cartridge of resins. In this paper, we illustrate the use of polymethylmethacrylate (PMMA) dialysis membranes with a high adsorptive capacity (Toray BK-F; Toray Industries, Inc., Tokyo, Japan). We have evaluated light chain removal by means of an original dialysis procedure using a double-filter circuit made of PMMA working in sequential dialysis (DELETE system). The system provides satisfactory results in terms of FLC removal and, at the same time, ensures an adequate dialysis treatment (Kt/V >1.5) with significant reduction in urea, creatinine, and β2-microglobulin. The dual PMMA filter system combines an acceptable cost/efficiency ratio when compared with other methods and constitutes a concrete prospect in FLC removal. Its preferential setting of use is in patients with MM or with monoclonal gammopathies, who are on chronic dialysis and maintain high circulating levels of FLC. PMID:23676829

  2. Size controlled synthesis of sub-100 nm monodisperse poly(methylmethacrylate) nanoparticles using surfactant-free emulsion polymerization.

    PubMed

    Camli, Sevket Tolga; Buyukserin, Fatih; Balci, Oguz; Budak, Gurer Guven

    2010-04-15

    Surfactant-free emulsion polymerization (SFEP) is a well-known technique for the production of polymeric nanoparticles that does not require post-synthetic cleaning steps. Obtaining hydrophobic particles at sub-100 nm scale, however, is quite challenging with this polymerization method. Here, we demonstrate a single step synthetic approach that yields poly(methylmethacrylate) (PMMA) nanoparticles with controlled sub-100 nm size and relatively high resultant solid content. Dynamic light scattering (DLS) was used for the particle characterization. Spherical and uniformly sized nanoparticles were confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Acetone was used as a cosolvent in order to obtain monodisperse sub-100 nm diameter particles. Stable PMMA nanoparticle dispersions were obtained for all formulations where the persulfate initiator causes the negative charges on the particle surface. The effects of acetone, monomer and initiator concentration were studied to optimize average particle hydrodynamic diameter and polydispersity index of the final particles. Non-crosslinked monodisperse PMMA nanoparticles (polydispersity index less than 0.05) with diameters from 32 nm to 72 nm were synthesized by using this method. PMID:20138293

  3. Enhanced surface flashover strength in vacuum of polymethylmethacrylate by surface modification using atmospheric-pressure dielectric barrier discharge

    SciTech Connect

    Shao, Tao Yang, Wenjin; Zhang, Cheng; Yan, Ping; Niu, Zheng; Schamiloglu, Edl

    2014-08-18

    Polymer materials, such as polymethylmethacrylate (PMMA), are widely used as insulators in vacuum. The insulating performance of a high-voltage vacuum system is mainly limited by surface flashover of the insulators rather than bulk breakdown. Non-thermal plasmas are an efficient method to modify the chemical and physical properties of polymer material surfaces, and enhance the surface insulating performance. In this letter, an atmospheric-pressure dielectric barrier discharge is used to treat the PMMA surface to improve the surface flashover strength in vacuum. Experimental results indicate that the plasma treatment method using Ar and CF{sub 4} (10:1) as the working gas can etch the PMMA surface, introduce fluoride groups to the surface, and then alter the surface characteristics of the PMMA. The increase in the surface roughness can introduce physical traps that can capture free electrons, and the fluorination can enhance the charge capturing ability. The increase in the surface roughness and the introduction of the fluoride groups can enhance the PMMA hydrophobic ability, improve the charge capturing ability, decrease the secondary electron emission yield, increase the surface resistance, and improve the surface flashover voltage in vacuum.

  4. Histology of a novel injectable filler (polymethylmethacrylate and cross-linked dextran in hydroxypropyl methylcellulose) in a rat model.

    PubMed

    Lee, Young Bok; Park, Sae Mi; Song, Eun Jong; Park, Jun-Gyu; Cho, Kyoung-Oh; Kim, Jin Wou; Yu, Dong Soo

    2014-08-01

    A novel injectable filler of polymethylmethacrylate (PMMA) and cross-linked dextran in hydroxypropyl methylcellulose was introduced in the commercial filler market. For soft tissue augmentation, safety and biocompatibility should be evaluated and the stability at the implantation site should be assessed using histologic evaluation. In order to evaluate the biocompatibility of the novel soft tissue filler, PMMA and cross-linked dextran in hydroxypropyl methylcellulose was subdermally injected into the skin of Sprague-Dawley Rats. Histologic evaluation was performed at 13 weeks and 12 months after the injection. Inflammatory cell infiltration, neovascularization, and fibrosis were scored according to defined grading systems. The mean score of the histologic evaluation was 5.7 and 3.9 at 13 weeks and 12 months, respectively. At 12 months after injection, the PMMA and cross-linked dextran in hydroxypropyl methylcellulose appeared to be kept in place through fine fibrous capsules. The mixture of PMMA and cross-linked dextran in hydroxypropyl methylcellulose can be safely applied for soft tissue augmentation with longevity of greater than 12 months. PMID:24684519

  5. Percutaneous Pedicle Screw Fixation with Polymethylmethacrylate Augmentation for the Treatment of Thoracolumbar Intravertebral Pseudoarthrosis Associated with Kummell's Osteonecrosis.

    PubMed

    Kim, Hyeun-Sung; Heo, Dong-Hwa

    2016-01-01

    Purpose. The purpose of our study is to evaluate the therapeutic efficacy of short-segment percutaneous pedicle screw fixation with polymethylmethacrylate (PMMA) augmentation for the treatment of osteoporotic thoracolumbar compression fracture with osteonecrosis. Methods. Osteoporotic thoracolumbar compression fractures with avascular necrosis were treated by short-segment PPF with PMMA augmentation. Eighteen were followed up for more than 2 years. The kyphotic angle, compression ratio, visual analog scale (VAS) score for back pain, and the Oswestry Disability Index (ODI) were analyzed. In addition, radiologic and clinical parameters of PPF group were compared with percutaneous vertebroplasty (PVP) group. Results. Vertebral height and kyphotic angle of the compressed vertebral bodies were significantly corrected after the operation (P < 0.05). Further, restored vertebral height was maintained during the 2 or more years of postoperative follow-up. Compared to the PVP group the postoperative compression ratio and kyphotic angle were significantly lower in the PPF group (P < 0.05). The postoperative ODI and VAS of the PVP group were significantly higher than the PPF (P < 0.05). Conclusions. According to our results, short-segment PPF with PMMA augmentation may be an effective minimally invasive treatment for osteoporosis in cases of osteoporotic vertebral compression fractures with Kummell's osteonecrosis. PMID:27595101

  6. Polymer-additive extraction via pressurized fluids and organic solvents of variously cross-linked poly(methylmethacrylates).

    PubMed

    Nazem, N; Taylor, L T

    2002-04-01

    Variously cross-linked poly(methylmethacrylates) (PMMAs) are synthesized with three additives incorporated at theoretically 1000 microg of the additive per gram of prepared polymer. The additives are Irganox 1010, Irganox 1076, and Irgafos 168. The in-house" synthesized polyacrylates are then subjected to supercritical fluid extraction (SFE) to determine if additive recovery is a function of percent cross-linking. Although considerable work in this regard has been performed with non-cross-linked polyolefins, the literature is lacking regarding polyacrylates. Some additive degradation apparently occurs during the synthesis, as judged by the increased complexity of the extract high-performance liquid chromatographic trace and the low percent recoveries observed especially for the Irganoxes. For low polymer cross-linking (1%), it appears that both PMMA synthetic reproducibility and readily observed polymer swelling during SFE are serious issues that adversely affect additive percent recovery and precision of results. Higher percent cross-linking yields more consistent analytical data than low percent cross-linking, even though the amount of additive extracted in all PMMA samples (regardless of cross-linking percentage) is essentially the same whether the extraction is via SFE or liquid-solid extraction with methylene chloride. Results for comparably cross-linked poly(ethylmethacrylate) and poly(butylmethacrylate) are similar to PMMA. PMID:12004935

  7. Location of injected polymethylmethacrylate microspheres influences the onset of late adverse effects: an experimental and histopathologic study

    PubMed Central

    de Jesus, Luciano Henrique; de Campos Hildebrand, Laura; Martins, Manoela Domingues; da Rosa, Francinne Miranda; Danilevicz, Chris Krebs; Sant’Ana Filho, Manoel

    2015-01-01

    Polymethylmethacrylate (PMMA) has been widely used in the correction of wrinkles because of its long-lasting cosmetic improvements. However, side effects and complications may occur, and its clinical appearance on the oral mucosa can be similar to that of inflammatory or neoplastic disease. The aim of this research was to compare the clinical and histopathologic responses to PMMA injected by two different methods. Twenty-two rats received an injection of PMMA using the tunneling technique (gold standard), with subcutaneous deposition of the filler in the face, or a variation of the technique with transcutaneous submucosal deposition of the filler in the cheek. The tissue reaction was analyzed clinically every 24 hours during the first week, then once a week for the following 3 months. Histologic evaluation was based on the local inflammatory response to the filler. No clinical changes were observed during the initial evaluation period (0–14 days). After 14 days, only the submucosal group showed extra-oral enlargement (n=4, 18.2%). Histopathologic analysis revealed nodule formation in four animals (18.2%) in the submucosal group, with no nodules observed in the subcutaneous group. The data obtained in this study demonstrate that the technique used to deliver the filler may influence the risk of adverse reactions. PMID:26346665

  8. Computer Simulation and Analysis on Flow Characteristics and Distribution Patterns of Polymethylmethacrylate in Lumbar Vertebral Body and Vertebral Pedicle

    PubMed Central

    Liu, Da; Liu, Xu-li; Zhang, Bo; Liao, Dong-fa; Li, Zhi-qiang; Zhou, Jiang-jun; Kang, Xia; Zheng, Wei; Lei, Wei

    2015-01-01

    This study was designed to analyze the flow and distribution of polymethylmethacrylate (PMMA) in vertebral body through computer simulation. Cadaveric lumbar vertebrae were scanned through electron beam tomography (EBT). The data was imported into Mimics software to build computational model. Vertebral body center and junction of pedicle and vertebral body were chosen as injection points. Silicone oil with viscosity of 100,000 cSt matching with PMMA bone cement was chosen for injection. The flow and distribution of silicone oil were analyzed using Fluent software. In vertebral body, silicone oil formed a circle-like shape centered by injection point on transverse and longitudinal sections, finally forming a sphere-like shape as a whole. Silicone oil diffused along lateral and posterior walls forming a circle-like shape on transverse section centered by injection point in pedicle, eventually forming a sphere-like shape as a whole. This study demonstrated that silicone oil flowed and diffused into a circle-like shape centered by injection point and finally formed a sphere-like shape as a whole in both vertebral body and pedicle. The flow and distribution of silicon oil in computational model could simulate PMMA distribution in vertebral body. It may provide theoretical evidence to reduce PMMA leakage risk during percutaneous vertebroplasty. PMID:26770969

  9. Influence of Nano-HA Coated Bone Collagen to Acrylic (Polymethylmethacrylate) Bone Cement on Mechanical Properties and Bioactivity

    PubMed Central

    Li, Tao; Weng, Xisheng; Bian, Yanyan; Zhou, Lei; Cui, Fuzhai; Qiu, Zhiye

    2015-01-01

    Objective This research investigated the mechanical properties and bioactivity of polymethylmethacrylate (PMMA) bone cement after addition of the nano-hydroxyapatite(HA) coated bone collagen (mineralized collagen, MC). Materials & Methods The MC in different proportions were added to the PMMA bone cement to detect the compressive strength, compression modulus, coagulation properties and biosafety. The MC-PMMA was embedded into rabbits and co-cultured with MG 63 cells to exam bone tissue compatibility and gene expression of osteogenesis. Results 15.0%(wt) impregnated MC-PMMA significantly lowered compressive modulus while little affected compressive strength and solidification. MC-PMMA bone cement was biologically safe and indicated excellent bone tissue compatibility. The bone-cement interface crosslinking was significantly higher in MC-PMMA than control after 6 months implantation in the femur of rabbits. The genes of osteogenesis exhibited significantly higher expression level in MC-PMMA. Conclusions MC-PMMA presented perfect mechanical properties, good biosafety and excellent biocompatibility with bone tissues, which has profoundly clinical values. PMID:26039750

  10. A cellular-automata and particle-tracking simulation of abrasive jet micromachining of polymethyl-methacrylate

    NASA Astrophysics Data System (ADS)

    Ciampini, D.; Papini, M.

    2011-08-01

    A cellular automaton simulation which is able to predict the geometry of micro-features etched into ductile erosive targets, as a result of abrasive jet micromachining (AJM), is presented. Similar to a previous simulation for the AJM of brittle erosive targets, the movement of individual erodent particles is tracked in a simulated environment, including their collisions with, and ricochet from, the mask and target substrate modeled as cellular-automatons. A new cell erosion algorithm is presented in order to allow the previous simulation to be applied to the AJM of ductile materials. A previously published empirical erosion rule, which related the erosion rate of ductile substrates caused by a jet, was also proven to be applicable, to a good approximation, to single particle impacts. With this new cell erosion algorithm, the predictions of the model compared well with measurements of the surface evolution of unmasked channels, masked micro-holes and micro-channels machined in polymethyl-methacrylate. The results also highlight the importance of modeling the effect of particle size on the prediction of the size and shape of features fabricated in ductile erosive materials using AJM.

  11. Curing of a silane coupling agent and its effect on the transverse strength of autopolymerizing polymethylmethacrylate-glass fibre composite.

    PubMed

    Vallittu, P K

    1997-02-01

    The aim of this study was to determine how curing gamma-methacryloxypropyltrimethoxysilane (gamma-MPS) to the surface of E-glass fibre affects the transverse strength of autopolymerizing polymethylmethacrylate-glass fibre composite (PMMA-GF). For this purpose, unidirectional glass fibres treated with gamma-MPS solution and cured for various lengths of time at different temperatures (+50 degrees C, +100 degrees C and +150 degrees C) were used as a strengthener of PMMA test specimens (n = 10 per group). The mean concentration of glass fibres in the test specimens was 17 wt%. The unreinforced test specimens and the test specimens reinforced with unsilanized fibres were compared, but no statistical difference in their transverse strengths was found (P = 0.568). The results also revealed that when the curing temperatures of the gamma-MPS were compared, the highest transverse strength (152 MPa) for the PMMA-GF composite was obtained by curing the MPS for 120 min at +100 degrees C; the lowest strength (91 MPa) was obtained by polymerizing the MPS at +150 degrees C (P < 0.001). However, SEM photomicrographs taken from the interface of the glass fibre and PMMA showed that the fibre adhered equally well to the PMMA treated at +100 degrees C or at +150 degrees C. This suggests that reduction in transverse strength of composite test specimens is caused by other factors, for example, by improper impregnation of PMMA into the fibre bundle, rather than by inadequate adhesion. PMID:9061621

  12. Water equivalence of NIPAM based polymer gel dosimeters with enhanced sensitivity for x-ray CT

    NASA Astrophysics Data System (ADS)

    Gorjiara, Tina; Hill, Robin; Bosi, Stephen; Kuncic, Zdenka; Baldock, Clive

    2013-10-01

    Two new formulations of N-isopropylacrylamide (NIPAM) based three dimensional (3D) gel dosimeters have recently been developed with improved sensitivity to x-ray CT readout, one without any co-solvent and the other one with isopropanol co-solvent. The water equivalence of the NIPAM gel dosimeters was investigated using different methods to calculate their radiological properties including: density, electron density, number of electrons per grams, effective atomic number, photon interaction probabilities, mass attenuation and energy absorption coefficients, electron collisional, radiative and total mass stopping powers and electron mass scattering power. Monte Carlo modelling was also used to compare the dose response of these gel dosimeters with water for kilovoltage and megavoltage x-ray beams and for megavoltage electron beams. We found that the density and electron density of the co-solvent free gel dosimeter are more water equivalent with less than a 2.6% difference compared to a 5.7% difference for the isopropanol gel dosimeter. Both the co-solvent free and isopropanol solvent gel dosimeters have lower effective atomic numbers than water, differing by 2.2% and 6.5%, respectively. As a result, their photoelectric absorption interaction probabilities are up to 6% and 19% different from water, respectively. Compton scattering and pair production interaction probabilities of NIPAM gel with isopropanol differ by up to 10% from water while for the co-solvent free gel, the differences are 3%. Mass attenuation and energy absorption coefficients of the co-solvent free gel dosimeter and the isopropanol gel dosimeter are up to 7% and 19% lower than water, respectively. Collisional and total mass stopping powers of both gel dosimeters differ by less than 2% from those of water. The dose response of the co-solvent free gel dosimeter is water equivalent (with <1% discrepancy) for dosimetry of x-rays with energies <100 keV while the discrepancy increases (up to 5%) for the

  13. Development of a scintillating optical fiber dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2014-01-01

    A radiation dosimeter for low dose rates based on a scintillating optical fiber coupled to a high gain photon-counting silicon photomultiplier (SiPM) for light readout was developed. The dosimeter satisfies most of the requirements for in-vivo, low dose-rate and real-time dosimetry. The device uses a small scintillator, is flexible and reasonably water-equivalent for photon energies above 100 keV [1,2]. Promising results were obtained when operating the device in current mode, detecting radiation from an X-ray tube in the 15-40 kV range and for anode currents as low as a few μA. As single-photon detectors, the major drawback of SiPMs is their high dark count rate (noise), which is a problem for low dose rate measurements in single photon counting mode. This drawback can be reduced by cooling the SiPMs or by using a much more efficient proposed solution in which two SiPMs operate in coincidence mode reading out the same optical fiber, thus allowing the rejection of false events triggered by dark noise. We have implemented a simple low-cost system, with dedicated front-end electronics operating in pulse mode for coincidence detection. Performance studies of the dosimeter operating in current mode, as a function of the X-ray tube current and voltage, show good sensitivity even for low radiation dose. When operating in pulse mode under low activity gamma irradiation, the coincidence system was able to reduce the dark noise to a residual value.

  14. Electromagnetic field exposure dosimeter. Final report, September 1992-May 1993

    SciTech Connect

    Feaga, A.C.; Hilliard, M.P.; Link, R.

    1994-07-28

    The growing concern about adverse health effects caused by electromagnetic radiation prompted the ideas for this dosimeter. Data have been presented that link prolonged exposure to electromagnetic radiation from power lines to leukemia and some types of cancer. At present, though, there is a lack of recording instrumentation to measure the prolonged exposure of an individual; thus, it is not possible to correlate properly the amount of exposure or dose to health effects. With the recent advances in small, low-power devices, a small measuring device can be developed. Once this is built, a large data base can be obtained to help correlate electromagnetic field exposure to health conditions. The objective of this project is to develop an instrument which can measure electromagnetic fields over a prolonged period of time. The instrument would be small, say about the size of a radio Walkman, and would be worn throughout the day while taking data, as the individual goes about normal activities. A PC would be used to retrieve the data from the instrument at the end of the day. The dosimeter comprises a triaxial ferrite-loaded coil sensor, a set of amplifiers and filters, analog-to-digital converters, a microcontroller, and random access data memory. The signals from the sensor are filtered into three frequency ranges: one to measure 60-Hz exposure and two harmonics, another to measure high-energy pulsed energy, and a third frequency range to record the activity level of the individual. The signals from the filters are digitized and read into a microcontroller. The microcontroller performs a few calculations and controls the flow of the data to either random access memory or to a computer. A computer is used to retrieve the data from the dosimeter, and can store and display the measured data.

  15. Heat-Processed Scutellariae Radix Enhances Anti-Inflammatory Effect against Lipopolysaccharide-Induced Acute Lung Injury in Mice via NF-κB Signaling

    PubMed Central

    Shin, Yu Ock; Park, Chan Hum; Lee, Gyeong-Hwan; Yokozawa, Takako; Roh, Seong-Soo; Rhee, Man Hee

    2015-01-01

    The present study was conducted to examine whether heat-processed Scutellariae Radix has an ameliorative effect on lipopolysaccharide- (LPS-) induced acute lung injury in mice. The effects of Scutellariae Radix heat-processed at 160°C (HSR) were compared with those of nonheat-processed Scutellariae Radix (NSR). The LPS-treated group displayed a markedly decreased body weight and significantly increased lung weight; however, the administration of NSR or HSR improved both the body and lung weights. The increased oxidative stress and inflammatory biomarker levels in the serum and lung were reduced significantly with HSR. The reduced superoxide dismutase and catalase increased significantly by both NSR and HSR. Also, the dysregulated oxidative stress and inflammation were significantly ameliorated by NSR and HSR. The expression of inflammatory mediators and cytokines by nuclear factor-kappa B activation was modulated through inhibition of a nuclear factor kappa Bα degradation. Also, lung histological change was markedly suppressed by HSR rather than NSR. Overall, the ameliorative effects of HSR were superior to those when being nonheat-processed. The representative flavonoid contents of Scutellariae Radix that include baicalin, baicalein, and wogonin were greater by heat process. These data reveal heat-processed Scutellariae Radix may be a critical factor involved in the improvement of lung disorders caused by LPS. PMID:26167192

  16. Radix Ilicis Pubescentis total flavonoids combined with mobilization of bone marrow stem cells to protect against cerebral ischemia/reperfusion injury

    PubMed Central

    Miao, Ming-san; Guo, Lin; Li, Rui-qi; Ma, Xiao

    2016-01-01

    Previous studies have shown that Radix Ilicis Pubescentis total flavonoids have a neuroprotective effect, but it remains unclear whether Radix Ilicis Pubescentis total flavonoids have a synergistic effect with the recombinant human granulocyte colony stimulating factor-mobilized bone marrow stem cell transplantation on cerebral ischemia/reperfusion injury. Rat ischemia models were administered 0.3, 0.15 and 0.075 g/kg Radix Ilicis Pubescentis total flavonoids from 3 days before modeling to 2 days after injury. Results showed that Radix Ilicis Pubescentis total flavonoids could reduce pathological injury in rats with cerebral ischemia/reperfusion injury. The number of Nissl bodies increased, Bax protein expression decreased, Bcl-2 protein expression increased and the number of CD34-positive cells increased. Therefore, Radix Ilicis Pubescentis total flavonoids can improve the bone marrow stem cell mobilization effect, enhance the anti-apoptotic ability of nerve cells, and have a neuroprotective effect on cerebral ischemia/reperfusion injury in rats. PMID:27073381

  17. Radix Ilicis Pubescentis total flavonoids combined with mobilization of bone marrow stem cells to protect against cerebral ischemia/reperfusion injury.

    PubMed

    Miao, Ming-San; Guo, Lin; Li, Rui-Qi; Ma, Xiao

    2016-02-01

    Previous studies have shown that Radix Ilicis Pubescentis total flavonoids have a neuroprotective effect, but it remains unclear whether Radix Ilicis Pubescentis total flavonoids have a synergistic effect with the recombinant human granulocyte colony stimulating factor-mobilized bone marrow stem cell transplantation on cerebral ischemia/reperfusion injury. Rat ischemia models were administered 0.3, 0.15 and 0.075 g/kg Radix Ilicis Pubescentis total flavonoids from 3 days before modeling to 2 days after injury. Results showed that Radix Ilicis Pubescentis total flavonoids could reduce pathological injury in rats with cerebral ischemia/reperfusion injury. The number of Nissl bodies increased, Bax protein expression decreased, Bcl-2 protein expression increased and the number of CD34-positive cells increased. Therefore, Radix Ilicis Pubescentis total flavonoids can improve the bone marrow stem cell mobilization effect, enhance the anti-apoptotic ability of nerve cells, and have a neuroprotective effect on cerebral ischemia/reperfusion injury in rats. PMID:27073381

  18. An RF dosimeter for independent SAR measurement in MRI scanners

    PubMed Central

    Qian, Di; El-Sharkawy, AbdEl-Monem M.; Bottomley, Paul A.; Edelstein, William A.

    2013-01-01

    Purpose: The monitoring and management of radio frequency (RF) exposure is critical for ensuring magnetic resonance imaging (MRI) safety. Commercial MRI scanners can overestimate specific absorption rates (SAR) and improperly restrict clinical MRI scans or the application of new MRI sequences, while underestimation of SAR can lead to tissue heating and thermal injury. Accurate scanner-independent RF dosimetry is essential for measuring actual exposure when SAR is critical for ensuring regulatory compliance and MRI safety, for establishing RF exposure while evaluating interventional leads and devices, and for routine MRI quality assessment by medical physicists. However, at present there are no scanner-independent SAR dosimeters. Methods: An SAR dosimeter with an RF transducer comprises two orthogonal, rectangular copper loops and a spherical MRI phantom. The transducer is placed in the magnet bore and calibrated to approximate the resistive loading of the scanner's whole-body birdcage RF coil for human subjects in Philips, GE and Siemens 3 tesla (3T) MRI scanners. The transducer loop reactances are adjusted to minimize interference with the transmit RF field (B1) at the MRI frequency. Power from the RF transducer is sampled with a high dynamic range power monitor and recorded on a computer. The deposited power is calibrated and tested on eight different MRI scanners. Whole-body absorbed power vs weight and body mass index (BMI) is measured directly on 26 subjects. Results: A single linear calibration curve sufficed for RF dosimetry at 127.8 MHz on three different Philips and three GE 3T MRI scanners. An RF dosimeter operating at 123.2 MHz on two Siemens 3T scanners required a separate transducer and a slightly different calibration curve. Measurement accuracy was ∼3%. With the torso landmarked at the xiphoid, human adult whole‑body absorbed power varied approximately linearly with patient weight and BMI. This indicates that whole-body torso SAR is on average

  19. Radiochromic leuko dye real time dosimeter, one way optical waveguide

    SciTech Connect

    Kronenberg, S.; McLaughlin, W.L.; Siebentritt, C.R.

    1984-12-18

    A radiochromic leuko dye dosimeter includes a plastic tube containing a solution of a radiochromic dye which is sensitive to ionizing radiation, one end of the tube being closed by a reflective surface, the opposite end of the tube being closed by a transparent plug to form a one-way optical waveguide. Light enters the tube through the transparent end thereof and is reflected back and exits through the transparent end. The intensity of the exiting light is measured to determine radiation induced absorption of the leuko dye.

  20. Lower limits of detection for thermal luminescent dosimeters

    SciTech Connect

    Spacher, P.J. ); Mis, F.J.; Klueber, M.R. )

    1990-08-01

    This paper reports that Groups of Panasonic UD-802 thermoluminescent dosimeters (TLDs) were irradiated to successively increasing doses of Cesium-137 gamma radiation (0.662 MeV gamma rays) and then processed using a Panasonic UD-710 automatic TLD reader. The results were subjected to statistical tests to determine the critical level, the level of detection, and the less-than level. The critical level is equivalent to 1.7 mrad, the lower limit of detection is equivalent to 5 mrad and the less-than level has a high range value of 7.5 mrad.

  1. An RF dosimeter for independent SAR measurement in MRI scanners

    SciTech Connect

    Qian, Di; Bottomley, Paul A.; El-Sharkawy, AbdEl-Monem M.; Edelstein, William A.

    2013-12-15

    Purpose: The monitoring and management of radio frequency (RF) exposure is critical for ensuring magnetic resonance imaging (MRI) safety. Commercial MRI scanners can overestimate specific absorption rates (SAR) and improperly restrict clinical MRI scans or the application of new MRI sequences, while underestimation of SAR can lead to tissue heating and thermal injury. Accurate scanner-independent RF dosimetry is essential for measuring actual exposure when SAR is critical for ensuring regulatory compliance and MRI safety, for establishing RF exposure while evaluating interventional leads and devices, and for routine MRI quality assessment by medical physicists. However, at present there are no scanner-independent SAR dosimeters. Methods: An SAR dosimeter with an RF transducer comprises two orthogonal, rectangular copper loops and a spherical MRI phantom. The transducer is placed in the magnet bore and calibrated to approximate the resistive loading of the scanner's whole-body birdcage RF coil for human subjects in Philips, GE and Siemens 3 tesla (3T) MRI scanners. The transducer loop reactances are adjusted to minimize interference with the transmit RF field (B{sub 1}) at the MRI frequency. Power from the RF transducer is sampled with a high dynamic range power monitor and recorded on a computer. The deposited power is calibrated and tested on eight different MRI scanners. Whole-body absorbed power vs weight and body mass index (BMI) is measured directly on 26 subjects. Results: A single linear calibration curve sufficed for RF dosimetry at 127.8 MHz on three different Philips and three GE 3T MRI scanners. An RF dosimeter operating at 123.2 MHz on two Siemens 3T scanners required a separate transducer and a slightly different calibration curve. Measurement accuracy was ∼3%. With the torso landmarked at the xiphoid, human adult whole‑body absorbed power varied approximately linearly with patient weight and BMI. This indicates that whole-body torso SAR is on

  2. The application of Sunna dosimeter film for process control at industrial gamma- and electron beam irradiation facilities

    NASA Astrophysics Data System (ADS)

    Kovács, A.; Baranyai, M.; Fuochi, P. G.; Lavalle, M.; Corda, U.; Miller, S.; Murphy, M.; O'Doherty, J.

    2004-09-01

    The Sunna dosimeter was introduced for dose determination in the dose range of 50-300 kGy by measuring optically stimulated luminescence. The usefulness of the dosimeter film has already been shown in food irradiation for routine process control. The aim of the present study was to check the performance of the Sunna dosimeter film for process control in radiation sterilization under industrial processing conditions, i.e. at high activity gamma irradiators and at high energy electron beam facilities. To ensure similar irradiation conditions during calibration and routine irradiation "in-plant calibration" was performed by irradiating the Sunna dosimeters together with ethanol-monochlorobenzene transfer standard and alanine reference standard dosimeters. The Sunna dosimeters were then irradiated together with the routine dosimeter of the actual plant during regular production runs and the absorbed doses measured by the different dosimeters agreed within ±2%(1 σ).

  3. Adaptation of a Pocket PC for Use as a Wearable Voice Dosimeter

    ERIC Educational Resources Information Center

    Popolo, Peter S.; Svec, Jan G.; Titze, Ingo R.

    2005-01-01

    This article deals with the adaptation of a commercially available Pocket PC for use as a voice dosimeter, a wearable device that measures the vocal dose of teachers or other individuals on the job, at home, and elsewhere during the course of an entire day. An engineering approach for designing a voice dosimeter is described, and design data are…

  4. Ceric and ferrous dosimeters show precision for 50-5000 rad range

    NASA Technical Reports Server (NTRS)

    Frigerio, N. A.; Henry, V. D.

    1968-01-01

    Ammonium thiocyanate, added to the usual ferrous sulfate dosimeter solution, yielded a very stable, precise and temperature-independent system eight times as sensitive as the classical Fricke system in the 50 to 5000 rad range. The ceric dosimeters, promising for use in mixed radiation fields, respond nearly independently of LET.

  5. PRESAGETM - Development and optimization studies of a 3D radiochromic plastic dosimeter - Part 1

    NASA Astrophysics Data System (ADS)

    Adamovics, J.; Jordan, K.; Dietrich, J.

    2006-12-01

    This paper studies the polymerization of six different transparent plastics as potential 3D dosimeter matrices. In addition, six different leuco dyes and sixteen different free radical initiators were evaluated. Finally, the photoreactivity of the dosimeter was studied so that the effect of exposure to UV could be minimized.

  6. Longevity Tests of High-Sensitivity BD-PND Bubble Dosimeters

    SciTech Connect

    Radev, R; Carlberg, E

    2002-07-09

    Medium- and very-high-sensitivity neutron bubble dosimeters (BD-PNDs) made by Bubble Technology Industries (BTI) were used to study the life span of such dosimeters in a standard setup with a {sup 252}Cf source. Although data on the longevity of bubble dosimeters with low and medium sensitivity exist, such data for dosimeters with high and very high sensitivity are not readily available. The manufacturer guarantees optimum dosimeter performance for 3 months after receipt. However, it is important to know the change in the dosimeters' characteristics with time, especially after the first 3 months. The long-term performance of four sets of very high sensitivity and one set of medium-sensitivity bubble dosimeters was examined for periods of up to 13 months. During that time, the detectors were exposed and reset more than 20 times. Although departures from initial detection sensitivity were observed in several cases, the detectors indicated a significantly longer life span than stated in the manufacturer's warranty. In addition, the change in the number of bubbles and in evaluated neutron dose as a function of the time from the end of exposure until the dosimeters were read was investigated.

  7. Dosimeter for the measurement of UV exposures related to melanoma induction.

    PubMed

    Turnbull, David J; Parisi, Alfio V

    2010-07-01

    This paper reports on the development of a dosimeter for the measurement of biologically effective UV exposures related to melanoma induction. The melanoma (UVMel) dosimeter is based on the combination of polysulfone and nalidixic acid. This research found that the combination of these photosensitive chromophores reacts to UV wavelengths from 290 to 390 nm. It was found that a large change in optical absorbance occurred at 345 nm when the dosimeter was employed to quantify the solar UV waveband. Preliminary results indicate that this UVMel dosimeter can measure exposures of more than 189 kJ m(-2) of biologically effective weighted solar UV radiation with an inter-dosimeter variability of no more than +/-5%. PMID:20551501

  8. Feasibility of Ultra-Thin Fiber-Optic Dosimeters for Radiotherapy Dosimetry

    PubMed Central

    Lee, Bongsoo; Kwon, Guwon; Shin, Sang Hun; Kim, Jaeseok; Yoo, Wook Jae; Ji, Young Hoon; Jang, Kyoung Won

    2015-01-01

    In this study, prototype ultra-thin fiber-optic dosimeters were fabricated using organic scintillators, wavelength shifting fibers, and plastic optical fibers. The sensor probes of the ultra-thin fiber-optic dosimeters consisted of very thin organic scintillators with thicknesses of 100, 150 and 200 μm. These types of sensors cannot only be used to measure skin or surface doses but also provide depth dose measurements with high spatial resolution. With the ultra-thin fiber-optic dosimeters, surface doses for gamma rays generated from a Co-60 therapy machine were measured. Additionally, percentage depth doses in the build-up regions were obtained by using the ultra-thin fiber-optic dosimeters, and the results were compared with those of external beam therapy films and a conventional fiber-optic dosimeter. PMID:26593917

  9. Effect of γ-irradiation on the volatile compounds of medicinal herb, Paeoniae Radix

    NASA Astrophysics Data System (ADS)

    Shim, Sung-Lye; Hwang, In-Min; Ryu, Keun-Young; Jung, Min-Seok; Seo, Hye-young; Kim, Hee-Yeon; Song, Hyun-Pa; Kim, Jae-Hun; Lee, Ju-Woon; Byun, Myung-Woo; Kwon, Joong-Ho; Kim, Kyong-Su

    2009-07-01

    A study was carried out to find the effect of γ-irradiation on contents of volatile compounds from medicinal herb, Paeoniae Radix ( Paenia albiflora Pallas var. trichocarpa Bunge). The volatile compounds of control, 1, 3, 5 and 10 kGy irradiated samples were extracted by simultaneous steam distillation and extraction (SDE) method and analyzed by gas chromatograph-mass spectrometer. The major volatile compounds were paeonol, ( E)-carveol, ( E, E)-2,4-octadienal, methyl salicylate, myrtanol and eugenol acetate. Volatile compounds belonging to chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons and miscellaneous were identified in all experimental samples. The types of volatile compounds in irradiated samples were similar to those of non-irradiated sample and the concentrations of these compounds differed between treatments. 1,3-Bis (1,1-dimethylethyl)-benzene was identified by using the selected ion monitoring (GC/MS-SIM) mode. The concentration of this compound increased with the increase of irradiation dose level. These results suggest that it could be used as the base data for the effect of γ-irradiation on medicinal herb.

  10. Evaluation of anti-fatigue activity of total saponins of Radix notoginseng

    PubMed Central

    Yong-xin, Xu; Jian-jun, Zhang

    2013-01-01

    Background & objectives: Several biological activities of total saponins of Radix notoginseng (TSRN), a trational Chinese medicine have been reported. The present study was carried out to investigate anti-fatigue activity of TSRN in male Kunming mice. Methods: Mice were divided into four groups. The first group designated as control group was administered with distilled water by gavage every day. The second, third and fourth groups designated as TSRN treatment groups were administered with TSRN of 20, 40 and 80 mg/kg body weight/day, respectively. The treatment continued for 28 days. Exhaustive swimming time, blood lactate and tissue glycogen contents of mice after swimming were determined. Results: TSRN extended exhaustive swimming time of mice, effectively delayed the increase of lactate in the blood, as well as increased the tissue glycogen contents. Interpretation & conclusions: TSRN showed promising anti-fatigue activity in animal model. However, further study is needed to elucidate the mechanism of the effect of TSRN on fatigue. PMID:23481065

  11. Distinguishing Radix Angelica sinensis from different regions by HS-SFME/GC-MS.

    PubMed

    Tan, Hong-Sheng; Hu, Dong-Dong; Song, Jing-Zheng; Xu, Yong; Cai, Shuang-Fan; Chen, Qi-Long; Meng, Qian-Wan; Li, Song-Lin; Chen, Shi-Lin; Mao, Qian; Xu, Hong-Xi

    2015-11-01

    An automated headspace solvent free microextraction (HS-SFME) based gas chromatography/mass spectrometry (GC/MS) was developed for discrimination of Radix Angelica sinensis (RAS) from different cultivation regions. The MS data were subjected to principal component analysis (PCA) and hierarchical clustering analysis (HCA) to rapidly find the potential characteristic components of RAS from top-geoherb region and non top-geoherb region. Totally, fifty-one volatile organic compounds (VOCs) were identified, in which β-ocimene, α-pinene, 3-methylbutanal, heptanes, butanal were identified as potential markers for distinguishing RAS from top-geoherb region and non top-geoherb region. Sulphur dioxide was detected in some commercial RAS samples, which implied that sulphur-fumigation might be the main reason for the quality inconsistencies of commercial RAS samples. These results suggested that RAS from top-geoherb region and non-top geoherb region could be discriminated by the method. And characteristic chemical markers found in current study can be used for ensuring consistent quality of top-geoherb of RAS. PMID:25976811

  12. Anti-tumor effect of Radix Paeoniae Rubra extract on mice bladder tumors using intravesical therapy

    PubMed Central

    Lin, Mei-Yi; Chiang, Su-Yin; Li, Yi-Zhen; Chen, Mei-Fang; Chen, Yueh-Sheng; Wu, Jin-Yi; Liu, Yi-Wen

    2016-01-01

    Radix Paeoniae Rubra (RPR) is the dried root of Paeonia lactiflora Pallas and Paeonia veitchii Lynch, and is a herbal medicine that is widely used in traditional Chinese medicine for the treatment of blood-heat and blood-stasis syndrome, similarly to Cortex Moutan. The present study identified the same three components in RPR and Cortex Moutan extracts. In addition, it has been reported that RPR has an anti-cancer effect. Bladder cancer is the seventh most common type of cancer worldwide. Due to the high recurrence rate, identifying novel drugs for bladder cancer therapy is essential. In the present study, RPR extract was evaluated as a bladder cancer therapy in vitro and in vivo. The present results revealed that RPR extract reduced the cell viability of bladder cancer cells with a half maximal inhibitory concentration of 1–3 mg/ml, and had an extremely low cytotoxic effect on normal urothelial cells. Additionally, RPR decreased certain cell cycle populations, predominantly cells in the G1 phase, and caused a clear sub-G increase. In a mouse orthotopic bladder tumor model, intravesical application of RPR extract decreased the bladder tumor size without altering the blood biochemical parameters of the mice. In summary, the present results demonstrate the anti-proliferative properties of RPR extract on bladder cancer cells, and its anti-bladder tumor effect in vivo. Compared to Cortex Moutan extract, RPR extract may provide a more effective alternative therapeutic strategy for the intravesical therapy of superficial bladder cancer. PMID:27446367

  13. Ultrasensitive Time-Resolved Fluoroimmunoassay for Saikosaponin a in Chaihu (Bupleuri Radix)

    PubMed Central

    Chao, Zhi; Cui, Qian; Tian, Enwei; Zeng, Weiping; Cai, Xuan; Li, Xiaolei; Tanaka, Hiroyuki; Shoyama, Yukihiro; Wu, Yingsong

    2016-01-01

    The aim of this study is to establish a time-resolved fluoroimmunoassay (TRFIA) system for quantitative analysis of saikosaponin a (SSa) in the crude drug of Chaihu (Bupleuri Radix). A 96-well microplate coated with rabbit anti-mouse IgG was incubated with the methanol extracts of Chaihu samples and a mouse anti-SSa monoclonal antibody, and a Eu3+-labeled SSa-human serum albumin conjugate was used as the tracer. The established competitive TRFIA showed a good fourth order polynomial fitting from 0.01 to 10.0 μg/mL for standard SSa sample with a detection limit of 0.006 μg/mL. The intra- and inter-assay coefficients of variation of the assay were 7.3% and 8.9%, respectively, and the average SSa recovery was 119.2%. For samples of Chaihu extract, the results of this assay showed a good correlation with those by enzyme-linked immunosorbent assay established previously. This TRFIA system is ultrasensitive for detecting SSa with a wide detection range and a good stability and represents the first attempt of using TRFIA for quality evaluation of the crude drug of Chaihu. PMID:26968034

  14. Effect of Lithospermi Radix on Contact Dermatitis Induced by Dinitrofluorobenzene in Mice

    PubMed Central

    Kim, Han-Na; Kim, Mi-Young; Choi, Chan-Hun; Kim, Byung-Joo; Kim, Kyung-Yoon; Kim, Gye-Yeop; Jeong, Hyun-Woo; Kim, Hyung-Woo

    2012-01-01

    Objective: The root of Lithospermum erythrorhizon Sieb. et Zucc. (Lithospermi Radix, LR) is a kind of heat clearing and blood cooling medicinal herbs. It can clear away heat and cool the blood, reduce toxins and disperse maculae. LR has long been used as efficacious therapy for inflammation, burns, frostbite and skin diseases such as eczema and psoriasis. Methods: In the present study, we investigate anti-allergic and anti-inflammatory effects of LR by using the 1-fluoro-2, 4- dinitrofluorobenzene (DNFB)-induced contact dermatitis mouse model. Results: Topical application of 10 mg/mL of LR effectively inhibited skin lesions induced by repeated paintings with DNFB. Topical application of LR also inhibited hyperplasia, edema, spongiosis and infiltrations of mononuclear cells. In addition, production levels of total immunoglobulin and IgG1 in serum were decreased by using LR in vivo. Conclusion: These data suggest that LR acts as an antiinflammatory agent, improving skin lesions in CD mice. PMID:25780635

  15. Radix Tetrastigma hemsleyani flavone inhibits proliferation, migration, and invasion of human lung carcinoma A549 cells

    PubMed Central

    Zhong, Liangrui; Zheng, Junxian; Sun, Qianqian; Wei, Kemin; Hu, Yijuan

    2016-01-01

    Radix Tetrastigma hemsleyani flavone (RTHF) is widely used as a traditional herb and has detoxification and anti-inflammatory effects. In this study, we investigated the potential effects of RTHF on the growth and metastasis of human lung adenocarcinoma A549 cells and evaluated its mechanisms. A549 cells were treated with RTHF at various concentrations for different periods. In vitro Cell Counting Kit-8 assay and colony formation methods showed that RTHF had dose- and time-dependent antiproliferation effects on A549 cells. A cell adhesion assay showed that RTHF decreased A549 cell adhesion in a dose-dependent manner. Cell invasion and migration were investigated using the Transwell assay and observed using an inverted microscope; the results showed that cell metastasis was significantly lower in the treatment group than that in the control group (P<0.01). Expression of metastasis-related matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) was detected by real-time polymerase chain reaction and Western blotting. The results showed that the expression of MMP-2, MMP-9, and TIMP-1 decreased, while that of TIMP-2 increased significantly in the RTHF group when compared with the results of the control group. These results show that RTHF exhibits antigrowth and antimetastasis activity in lung cancer A549 cells by decreasing the expression of MMP-2/-9 and TIMP-1 and increasing that of TIMP-2. PMID:26893573

  16. Scutellaria radix Extract as a Natural UV Protectant for Human Skin.

    PubMed

    Seok, Jin Kyung; Kwak, Jun Yup; Choi, Go Woon; An, Sang Mi; Kwak, Jae-Hoon; Seo, Hyeong-Ho; Suh, Hwa-Jin; Boo, Yong Chool

    2016-03-01

    Ultraviolet (UV) radiation induces oxidative injury and inflammation in human skin. Scutellaria radix (SR, the root of Scutellaria baicalensis Georgi) contains flavonoids with high UV absorptivity and antioxidant properties. The purpose of this study was to examine the potential use of SR extract as an additive in cosmetic products for UV protection. SR extract and its butanol (BuOH) fraction strongly absorbed UV radiation and displayed free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radials and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals. They also attenuated the UV-induced death of HaCaT cells. Sunscreen creams, with or without supplementation of SR extract BuOH fraction, were tested in vivo in human trials to evaluate potential skin irritation and determine the sun protection factor (SPF). Both sunscreen creams induced no skin irritation. A sunscreen cream containing 24% ZnO showed an SPF value of 17.8, and it increased to 22.7 when supplemented with 5% SR extract BuOH fraction. This study suggests that SR-derived materials are useful as safe cosmetic additives that provide UV protection. PMID:26620130

  17. Interaction between Z-ligustilide from Radix Angelica sinensis and human serum albumin.

    PubMed

    Chen, Tingting; Zhu, Xiting; Chen, Qi; Ge, Ming; Jia, Xueping; Wang, Xiang; Ge, Cunwang

    2015-11-01

    Z-ligustilide (LIG), an essential oil extract from Radix Angelica sinensis, has broad pharmaceutical applications in treating cardiovascular and cerebrovascular diseases. Interaction of LIG with the major transport protein of human blood circulation, human serum albumin (HSA) has been investigated by steady-state, UV-vis and circular dichroism (CD) spectroscopic methods, as well as the effect of metal ions (e.g. Zn(2+), Cu(2+), Fe(3+), Co(2+), Ni(2+)) on the LIG-HSA system. Fluorescence results revealed that a moderate binding affinity (1.59 × 10(4) M(-1) at 298 K) between LIG and HSA with a 1:1 stoichiometry. Thermodynamic analysis of the binding data (ΔS = +12.96 J mol(-1) K(-1) and ΔH =- 20.11 kJ mol(-1)) suggested the involvement of hydrophobic and van der Waals forces, as well as hydrogen bonding in the complex formation. The specific binding distance r (3.75 nm) between donor (Trp-214) and acceptor (LIG) was obtained according to fluorescence resonance energy transfer. CD results showed that slight conformational changes occurred in the protein upon complexation with LIG. PMID:25976824

  18. Endodontic management of a mandibular second molar with radix entomolaris: a case report

    PubMed Central

    Kandaswamy, Deivanayagam; Jayaprakash, Nachimuthu

    2014-01-01

    The presence of radix entomolaris (RE) in a mandibular first molar is a common occurrence in certain ethnic groups, but the presence of RE in a mandibular second molar is a rare occurrence. In the present case, RE was identified from preoperative radiographs and confirmed using cone-beam computed tomography (CBCT). The access cavity was modified to locate the RE. Cleaning and shaping were performed with nickel-titanium rotary instruments. Obturation was completed with gutta-percha cones using AH Plus (Dentsply Detrey GmbH) as sealer. From the CBCT axial images, the RE was determined to have a Type III curvature by the De Moor classification, Type B separate RE by the Carlsen and Alexandersen classification, and radiographically, a Type i image by the Wang classification. The presence of RE in the mandibular second molar makes it essential to anticipate and treat the distolingual root canal. This case report highlights the usefulness of CBCT for assessing RE in the mandibular second molar, which can help the clinician in making a confirmatory diagnosis and assessing the morphology of the root canal. PMID:24790927

  19. Chromatographic analysis of Polygalae Radix by online hyphenating pressurized liquid extraction

    NASA Astrophysics Data System (ADS)

    Song, Yuelin; Song, Qingqing; Li, Jun; Shi, Shepo; Guo, Liping; Zhao, Yunfang; Jiang, Yong; Tu, Pengfei

    2016-06-01

    Practicing “green analytical chemistry” is of great importance when profiling the chemical composition of complex matrices. Herein, a novel hybrid analytical platform was developed for direct chemical analysis of complex matrices by online hyphenating pressurized warm water extraction followed by turbulent flow chromatography coupled with high performance liquid chromatography-tandem mass spectrometry (PWWE-TFC-LC-MS/MS). Two parallel hollow guard columns acted as extraction vessels connected to a long narrow polyether ether ketone tube, while warm water served as extraction solvent and was delivered at a flow rate of 2.5 mL/min to generate considerable back pressure at either vessel. A column oven heated both the solvent and crude materials. A TFC column, which is advantageous for the comprehensive trapping of small molecular substances from fluids under turbulent flow conditions, was employed to transfer analytes from the PWWE module to LC-MS/MS. Two electronic valves alternated each vessel between extraction and elution phases. As a proof-of-concept, a famous herbal medicine for the treatment of neurodegenerative disorders, namely Polygalae Radix, was selected for the qualitative and quantitative analyses. The results suggest that the hybrid platform is advantageous in terms of decreasing time, material, and solvent consumption and in its automation, versatility, and environmental friendliness.

  20. Synthesis, characterization, antioxidant activity and neuroprotective effects of selenium polysaccharide from Radix hedysari.

    PubMed

    Wei, Dongfeng; Chen, Tong; Yan, Mingfei; Zhao, Wanghong; Li, Fei; Cheng, Weidong; Yuan, Lixia

    2015-07-10

    Beta-amyloid (Aβ) peptide, the hallmark of Alzheimer's disease, invokes oxidative damage to neurons and eventually leads to neuronal death. Selenylation modification of polysaccharide obtained from Radix hedysari (RHP) was studied to access antioxidant activities and neuroprotective effects against oxidative stress and apoptosis induced by Aβ25-35 in vitro. A series of the selenylation derivatives of RHP (Se-RHP) was synthesized using nitric acid-sodium selenite (HNO3-Na2SeO3) method. The organic selenium content of Se-RHP increased from 1.04 to 3.29 mg/g. However, compared with the weight-average molecular mass (Mw) of RHP, Mw of Se-RHP showed a significant decrease, and varied from 27.7 kDa to 62.7 kDa. FT-IR spectra and (13)C NMR spectra indicated the selenite groups had been introduced mainly at the C-6 positions of RHP. Compared with RHP, Se-RHP showed greater antioxidant activities in vitro. Furthermore, both RHP and Se-RHP3 had neuroprotective effects against Aβ25-35-induced oxidative stress and apoptosis in SH-SY5Y human neuroblastoma cells, which might be a potential therapeutic agent for preventing or treating neurodegenerative diseases. PMID:25857971

  1. Non-thermal plasma treatment of Radix aconiti wastewater generated by traditional Chinese medicine processing.

    PubMed

    Wen, Yiyong; Yi, Jianping; Zhao, Shen; Jiang, Song; Chi, Yuming; Liu, Kefu

    2016-06-01

    The wastewater effluent from Radix aconiti processing, an important step in the production processes of traditional Chinese medicine (TCM), is a type of toxic wastewater and difficult to treat. Plasma oxidation methods have emerged as feasible techniques for effective decomposition of toxic organic pollutants. This study examined the performance of a plasma reactor operated in a dielectric barrier discharge (DBD) to degrade the effluent from R. aconiti processing. The effects of treatment time, discharge voltage, initial pH value and the feeding gas for the reactor on the degradation of this TCM wastewater were investigated. A bacterium bioluminescence assay was adopted in this study to test the toxicity of the TCM wastewater after non-thermal plasma treatment. The degradation ratio of the main toxic component was 87.77% after 60min treatment with oxygen used as feed gas and it was 99.59% when the initial pH value was 8.0. High discharge voltage and alkaline solution environment were beneficial for improving the degradation ratio. The treatment process was found to be capable of reducing the toxicity of the wastewater to a low level or even render it non-toxic. These experimental results suggested that the DBD plasma method may be a competitive technology for primary decomposition of biologically undegradable toxic organic pollutants in TCM wastewater. PMID:27266306

  2. Metabolism of tanshinone IIA, cryptotanshinone and tanshinone I from Radix Salvia miltiorrhiza in zebrafish.

    PubMed

    Wei, Yingjie; Li, Ping; Wang, Changmei; Peng, Yunru; Shu, Luan; Jia, Xiaobin; Ma, Wenquan; Wang, Bing

    2012-01-01

    The study aimed to investigate the potential of zebrafish in imitating mammal phase I metabolism of natural compounds. Three diterpenoid quinones from Radix Salvia miltiorrhiza, namely tanshinone IIA (TIIA), cryptotanshinone (Cry) and tanshinone I (TI) were selected as model compounds, and their metabolites mediated by zebrafish were characterized using a high-performance liquid chromatography coupled ion-trap mass spectrometry (HPLC/IT-MSn) method with electrospray ionization in positive mode. The separation was performed with a Zorbax C-18 column using a binary gradient elution of 0.05% formic acid acetonitrile/0.05% formic acid water. According to the MS spectra and after comparison with reference standards and literature reports, hydroxylation, dehydrogenation or D-ring hydrolysis metabolites of TIIA and Cry but not of TI were characterized, which coincided with those reported using regular in vivo or in vitro metabolic analysis methods, thus verifying that zebrafish can successfully imitate mammalian phase I metabolism which instills further confidence in using zebrafish as a novel and prospective metabolism model. PMID:22810195

  3. Polysaccharide enhances Radix Saposhnikoviae efficacy through inhibiting chromones decomposition in intestinal tract.

    PubMed

    Yang, Jing-Ming; Jiang, Hua; Dai, Hong-Liang; Wang, Zi-Wei; Jia, Gui-Zhi; Meng, Xiang-Cai

    2016-01-01

    Vegetative but not reproductive stage of Saposhnikovia divaricate (Turxz.) schischk possesses pharmacological activities. However, our recent study showed that reproductive S. divaricate supplemented with polysaccharide showed evidently elevated pharmacological activities and increased cimifugin content in rat serum. The aims of present study were to assess the influence of polysaccharides on the chromones pharmacological activities in Radix Saposhnikoviae (RS), the dried root of vegetative stage of S. divaricate, and to explore the underlying mechanisms. Only cimifugin was detected in the plasma of chromone treated animals and RS polysaccharide significantly increased the plasma content of cimifugin. It was shown that neither cimifugin absorption nor glycoside components transformation in simulated digestive fluid was affected by RS polysaccharide. However, a significant promotion of transformation of cimifugin to more stable prime-O-glucosylcimifugin (PGCN) by RS polysaccharide, and a protective effect of polysaccharide on chromone components were observed in small intestine solutions. Meanwhile, RS polysaccharide produced a significant elevation of cimifugin and PGCN concentration in vivo. Based on these findings, we concluded that RS polysaccharide could greatly increase the content of cimifugin, which might be related to its degradation-proof effect on cimifugin, via transforming cimifugin to comparatively more stable PGCN and spatial structure protection. PMID:27595868

  4. Investigation of Antioxidant Interactions between Radix Astragali and Cimicifuga foetida and Identification of Synergistic Antioxidant Compounds

    PubMed Central

    Wang, Fei; Zhao, Shancang; Li, Feng; Zhang, Bo; Qu, Yi; Sun, Tianlei; Luo, Ting; Li, Dapeng

    2014-01-01

    The medicinal plants of Huang-qi (Radix Astragali) and Sheng-ma (Cimicifuga foetida) demonstrate significantly better antioxidant effects when used in combination than when used alone. However, the bioactive components and interactional mechanism underlying this synergistic action are still not well understood. In the present study, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay was employed to investigate the antioxidant capacity of single herbs and their combination with the purpose of screening synergistic antioxidant compounds from them. Chromatographic isolation was performed on silica gel, Sephadex LH-20 columns and HPLC, and consequently to yield formononetin, calycosin, ferulic acid and isoferulic acid, which were identified by their retention time, UV λmax, MS and MS/MS data. The combination of isoferulic acid and calycosin at a dose ratio of 1∶1 resulted in significant synergy in scavenging DPPH radicals and ferric reducing antioxidant power (FRAP) assay. Furthermore, the protective effects of these four potential synergistic compounds were examined using H2O2-induced HepG2 Cells bioassay. Results revealed that the similar synergy was observed in the combination of isoferulic acid and calycosin. These findings might provide some theoretical basis for the purported synergistic efficiency of Huang-qi and Sheng-ma as functional foods, dietary supplements and medicinal drugs. PMID:24498048

  5. Effects of ferulic acid on antioxidant activity in Angelicae Sinensis Radix, Chuanxiong Rhizoma, and their combination.

    PubMed

    Wang, Lin-Yan; Tang, Yu-Ping; Liu, Xin; Zhu, Min; Tao, Wei-Wei; Li, Wei-Xia; Duan, Jin-Ao

    2015-06-01

    The present study aimed at exploring different roles of the same compound in different environment, using preparative HPLC, and the significance to investigating bio-active constituents in traditional Chinese medicine (TCM) on the basis of holism. In this study, the depletion of target component ferulic acid (FA) by using preparative HPLC followed by antioxidant activity testing was applied to investigate the roles of FA in Angelicae Sinensis Radix (DG), Chuanxiong Rhizoma (CX) and their combination (GX). The antioxidant activity was performed by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity testing. FA was successfully and exclusively depleted from DG, CX, and GX, respectively. By comparing the effects of the samples, it was found that FA was one of the main antioxidant constituents in DG, CX and GX, and the roles of FA were DG > CX > GX. Furthermore, the effects of FA varied at different doses in these herbs. This study provided a reliable and effective approach to clarifying the contribution of same compound in different TCMs to their bio-activities. The role of a constituent in different TCMs might be different, and a component with the same content might have different effects in different chemical environments. Furthermore, this study also suggested the potential utilization of preparative HPLC in the characterization of the roles of multi-ingredients in TCM. PMID:26073335

  6. Comparison of Two Different Astragali Radix by a ¹H NMR-Based Metabolomic Approach.

    PubMed

    Li, Ai-Ping; Li, Zhen-Yu; Sun, Hai-Feng; Li, Ke; Qin, Xue-Mei; Du, Guan-Hua

    2015-05-01

    Astragali Radix (AR) is a commonly used herbal drug in traditional chinese medicine and is widely used for the treatment of diabetes, cardiovascular diseases, nephropathy, and neuropathy. The main source of AR in China is the dried root of Astragalus membranaceus var. mongholicus (Bge.) Hsiao, and both cultivated and wild ARs are used clinically. A systematic comparison of cultivated AR (GS-AR) and wild AR (SX-AR) should be performed to ensure the clinical efficacy and safety. In this study, the chemical composition of the two different ARs, which were collected in the Shanxi (wild) and Gansu (cultivated) provinces, were compared by NMR-based metabolic fingerprint coupled with multivariate analysis. The SX-AR- and GS-AR-induced metabolic changes in the endogenous metabolites in mice were also compared. The results showed that SX-AR and GS-AR differed significantly not only in the primary metabolites but also in the secondary metabolites. However, alterations among the endogenous metabolites in the serum, lung, liver, and spleen were relatively small. This study provided a novel and valuable method for the evaluation of the consistency and diversity of herbal drugs, and further studies should be conducted on the difference in polysaccharides as well as the biological effects between the two kinds of AR. PMID:25844502

  7. Polysaccharide enhances Radix Saposhnikoviae efficacy through inhibiting chromones decomposition in intestinal tract

    PubMed Central

    Yang, Jing-Ming; Jiang, Hua; Dai, Hong-Liang; Wang, Zi-Wei; Jia, Gui-Zhi; Meng, Xiang-Cai

    2016-01-01

    Vegetative but not reproductive stage of Saposhnikovia divaricate (Turxz.) schischk possesses pharmacological activities. However, our recent study showed that reproductive S. divaricate supplemented with polysaccharide showed evidently elevated pharmacological activities and increased cimifugin content in rat serum. The aims of present study were to assess the influence of polysaccharides on the chromones pharmacological activities in Radix Saposhnikoviae (RS), the dried root of vegetative stage of S. divaricate, and to explore the underlying mechanisms. Only cimifugin was detected in the plasma of chromone treated animals and RS polysaccharide significantly increased the plasma content of cimifugin. It was shown that neither cimifugin absorption nor glycoside components transformation in simulated digestive fluid was affected by RS polysaccharide. However, a significant promotion of transformation of cimifugin to more stable prime-O-glucosylcimifugin (PGCN) by RS polysaccharide, and a protective effect of polysaccharide on chromone components were observed in small intestine solutions. Meanwhile, RS polysaccharide produced a significant elevation of cimifugin and PGCN concentration in vivo. Based on these findings, we concluded that RS polysaccharide could greatly increase the content of cimifugin, which might be related to its degradation-proof effect on cimifugin, via transforming cimifugin to comparatively more stable PGCN and spatial structure protection. PMID:27595868

  8. Chromatographic analysis of Polygalae Radix by online hyphenating pressurized liquid extraction

    PubMed Central

    Song, Yuelin; Song, Qingqing; Li, Jun; Shi, Shepo; Guo, Liping; Zhao, Yunfang; Jiang, Yong; Tu, Pengfei

    2016-01-01

    Practicing “green analytical chemistry” is of great importance when profiling the chemical composition of complex matrices. Herein, a novel hybrid analytical platform was developed for direct chemical analysis of complex matrices by online hyphenating pressurized warm water extraction followed by turbulent flow chromatography coupled with high performance liquid chromatography-tandem mass spectrometry (PWWE-TFC-LC-MS/MS). Two parallel hollow guard columns acted as extraction vessels connected to a long narrow polyether ether ketone tube, while warm water served as extraction solvent and was delivered at a flow rate of 2.5 mL/min to generate considerable back pressure at either vessel. A column oven heated both the solvent and crude materials. A TFC column, which is advantageous for the comprehensive trapping of small molecular substances from fluids under turbulent flow conditions, was employed to transfer analytes from the PWWE module to LC-MS/MS. Two electronic valves alternated each vessel between extraction and elution phases. As a proof-of-concept, a famous herbal medicine for the treatment of neurodegenerative disorders, namely Polygalae Radix, was selected for the qualitative and quantitative analyses. The results suggest that the hybrid platform is advantageous in terms of decreasing time, material, and solvent consumption and in its automation, versatility, and environmental friendliness. PMID:27272557

  9. Chromatographic analysis of Polygalae Radix by online hyphenating pressurized liquid extraction.

    PubMed

    Song, Yuelin; Song, Qingqing; Li, Jun; Shi, Shepo; Guo, Liping; Zhao, Yunfang; Jiang, Yong; Tu, Pengfei

    2016-01-01

    Practicing "green analytical chemistry" is of great importance when profiling the chemical composition of complex matrices. Herein, a novel hybrid analytical platform was developed for direct chemical analysis of complex matrices by online hyphenating pressurized warm water extraction followed by turbulent flow chromatography coupled with high performance liquid chromatography-tandem mass spectrometry (PWWE-TFC-LC-MS/MS). Two parallel hollow guard columns acted as extraction vessels connected to a long narrow polyether ether ketone tube, while warm water served as extraction solvent and was delivered at a flow rate of 2.5 mL/min to generate considerable back pressure at either vessel. A column oven heated both the solvent and crude materials. A TFC column, which is advantageous for the comprehensive trapping of small molecular substances from fluids under turbulent flow conditions, was employed to transfer analytes from the PWWE module to LC-MS/MS. Two electronic valves alternated each vessel between extraction and elution phases. As a proof-of-concept, a famous herbal medicine for the treatment of neurodegenerative disorders, namely Polygalae Radix, was selected for the qualitative and quantitative analyses. The results suggest that the hybrid platform is advantageous in terms of decreasing time, material, and solvent consumption and in its automation, versatility, and environmental friendliness. PMID:27272557

  10. Puerariae radix isoflavones and their metabolites inhibit growth and induce apoptosis in breast cancer cells

    SciTech Connect

    Lin, Y.-J.; Hou, Y.C.; Lin, C.-H.; Hsu, Y.-A.; Sheu, Jim J.C.; Lai, C.-H.; Chen, B.-H.; Lee Chao, Pei-Dawn; Wan Lei Tsai, F.-J.

    2009-01-23

    Puerariae radix (PR) is a popular natural herb and a traditional food in Asia, which has antithrombotic and anti-allergic properties and stimulates estrogenic activity. In the present study, we investigated the effects of the PR isoflavones puerarin, daidzein, and genistein on the growth of breast cancer cells. Our data revealed that after treatment with PR isoflavones, a dose-dependent inhibition of cell growth occurred in HS578T, MDA-MB-231, and MCF-7 cell lines. Results from cell cycle distribution and apoptosis assays revealed that PR isoflavones induced cell apoptosis through a caspase-3-dependent pathway and mediated cell cycle arrest in the G2/M phase. Furthermore, we observed that the serum metabolites of PR (daidzein sulfates/glucuronides) inhibited proliferation of the breast cancer cells at a 50% cell growth inhibition (GI{sub 50}) concentration of 2.35 {mu}M. These results indicate that the daidzein constituent of PR can be metabolized to daidzein sulfates or daidzein glucuronides that exhibit anticancer activities. The protein expression levels of the active forms of caspase-9 and Bax in breast cancer cells were significantly increased by treatment with PR metabolites. These metabolites also increased the protein expression levels of p53 and p21. We therefore suggest that PR may act as a chemopreventive and/or chemotherapeutic agent against breast cancer by reducing cell viability and inducing apoptosis.

  11. A modified Fricke gel dosimeter for fast electron blood dosimetry

    NASA Astrophysics Data System (ADS)

    Del Lama, L. S.; de Góes, E. G.; Sampaio, F. G. A.; Petchevist, P. C. D.; de Almeida, A.

    2014-12-01

    It has been suggested for more than forty years that blood and blood components be irradiated before allogeneic transfusions for immunosuppressed patients in order to avoid the Transfusion-Associated Graft-versus-Host Disease (TA-GVHD). Whole blood, red blood cells, platelets and granulocytes may have viable T cells and should be irradiated before transfusion for different patient clinical conditions. According to international guides, absorbed doses from 25 up to 50 Gy should be delivered to the central middle plane of each blood bag. Although gamma and X-rays from radiotherapy equipments and dedicated cell irradiators are commonly used for this purpose, electron beams from Linear Accelerators (LINACs) could be used as well. In this work, we developed a methodology able to acquire dosimetric data from blood irradiations, especially after fast electrons exposures. This was achieved using a proposed Fricke Xylenol Gel (FXGp) dosimeter, which presents closer radiological characteristics (attenuation coefficients and stopping-powers) to the whole blood, as well as complete absorbed dose range linearity. The developed methodology and the FXGp dosimeter were also able to provide isodose curves and field profiles for the irradiated samples.

  12. Development of a passive dosimeter for hydrogen fluoride monitoring

    SciTech Connect

    Young, M.S.; Monat, J.P.

    1983-02-01

    Hydrogen fluoride (HF), a toxic industrial chemical, is used in the manufacture of most fluorine products and in many other industrial processes. Major uses are in fluorocarbon manufacture, aluminum production, glass etching, steel pickling, uranium processing, and as a catalyst for petroleum refining. A reliable passive dosimeter has been developed for sampling of airborne hydrogen fluoride vapor. The device is small (7.7 cm x 5.4 cm x 1.9 cm) and can easily and conveniently be worn on one's lapel. It consists of polyethylene and polypropylene parts and an alkaline impregnated polypropylene collection element. It is completely self-contained requiring no pumps, impingers, or sampling tubes. Subsequent to sampling, the collection element is analyzed quickly and easily with a fluoride selective-ion electrode. Laboratory tests were conducted to determine precision, linearity, interference effects, influences of temperature and humidity, and collection element stability over time. Results of the tests indicate that the Gasbadge/sup TM/ HF dosimeter is an excellent passive HF monitor for work spaces, and that results obtained with it are accurate within +/- 17.4% in the action range and +/- 10.3% overall. These results have been corroborated in a field study. (JMT)

  13. The Effect of Primer on Bond Strength of Silicone Prosthetic Elastomer to Polymethylmethacrylate: An in vitro Study

    PubMed Central

    C.M., Ravi Kumar; A.A., Ponnanna; Bithu, Arvind Singh; Shah, Kelvin; Prajapati, Soham

    2015-01-01

    Introduction: The aim of the study is to evaluate interfacial bond strength between silicone prosthetic elastomers and polymethylmethacrylate (PMMA). Materials and Methods: Silicone elastomers were attached to PMMA and a total 120 specimens were fabricated which were then subdivided into 12 sub-groups. Each sample was then subjected to laboratory test to determine the bond strength. The specimen of silicone elastomer bonded to acrylic of different surfaces was placed into universal testing machine (HOUNSFIELD HT-400) for “PEEL TEST”. All the values obtained were tabulated and subjected to statistical analysis. Result: The bond strength of silicone elastomer to acrylic resin (TRAVELON) noticed highest (Mean 4.826 ± 0.008 n/mm) when only primer was used as a surface treatment. When silicone elastomer bonded to acrylic resin (DPI) showed the bond strength of (4.351 ± 0.0089) when only primer was used as a surface treatment. Whereas the least bond strength values were found when the silicone bonded to acrylic surface treated by 120 grit sand paper that is (0.076 ± 0.00 n/mm) and (0.082 ± 0.01 n/mm) for DPI and TRAVELON respectively. Conclusion: The bond strength of silicone elastomer to acrylic resin was higher when primer was used on the acrylic surface. The bond strength of silicone elastomer to acrylic resin was more with travelon resin when compared to DPI resin. But when silicone was bonded to acrylic surface with sand papering, showed less bond strength. PMID:25954703

  14. Surgical results of cranioplasty with a polymethylmethacrylate customized cranial implant in pediatric patients: a single-center experience.

    PubMed

    Fiaschi, Pietro; Pavanello, Marco; Imperato, Alessia; Dallolio, Villiam; Accogli, Andrea; Capra, Valeria; Consales, Alessandro; Cama, Armando; Piatelli, Gianluca

    2016-06-01

    OBJECTIVE Cranioplasty is a reconstructive procedure used to restore skull anatomy and repair skull defects. Optimal skull reconstruction is a challenge for neurosurgeons, and the strategy used to achieve the best result remains a topic of debate, especially in pediatric patients for whom the continuing skull growth makes the choice of material more difficult. When the native bone flap, which is universally accepted as the preferred option in pediatric patients, is unavailable, the authors' choice of prosthetic material is a polymethylmethacrylate (PMMA) implant designed using a custom-made technique. In this paper the authors present the results of their clinical series of 12 custom-made PMMA implants in pediatric patients. METHODS A retrospective study of the patients who had undergone cranioplasty at Gaslini Children's Hospital between 2006 and 2013 was conducted. A total of 12 consecutive cranioplasties in 12 patients was reviewed, in which a patient-specific PMMA implant was manufactured using a virtual 3D model and then transformed into a physical model using selective laser sintering or 3D printing. All patients or parents were administered a questionnaire to assess how the patient/parent judged the aesthetic result. RESULTS Patient age at craniectomy ranged from 5 months to 12.5 years, with a mean age of 84.33 months at cranioplasty. The mean extension of the custom-made plastic was 56.83 cm(2). The mean time between craniectomy and cranioplasty was 9.25 months. The mean follow-up duration was 55.7 months. No major complications were recorded; 3 patients experienced minor/moderate complications (prosthesis dislocation, granuloma formation, and fluid collection). CONCLUSIONS In this patient series, PMMA resulted in an extremely low complication rate and the custom-made technique was associated with an excellent grade of patient or parent satisfaction on long-term follow up. PMID:26824593

  15. LC-MS/MS determination and pharmacokinetics study of puerarin and daidzein in rat plasma after oral administration of Gegenqinlian decoction and Radix Puerariae extract

    PubMed Central

    Zhang, Yifan; Yuan, Jin; Wang, Ying; Wang, Yue; An, Rui; Wang, Xinhong

    2014-01-01

    Background: Gegenqinlian decoction (GQD) is a famous traditional medicine recipe. It is composed of four herbs including Radix Puerariae (GG), Radix Scutellariae (HQ), Rhizoma Coptidis (HL) and Radix Glycyrrhizae (GC), which is widely used for treating gastro-intestinal disorders in the clinical practice of Traditional Chinese medicine (TCM). The aim of this study was to compare the pharmacokinetics of puerarin and daidzein in rats following oral administration of Gegenqinlian Decoction and Radix Puerariae extract. Thus, a sensitive and selective liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated for simultaneous determination of puerarin and daidzein in rat plasma following oral administration of Gegenqinlian Decoction and Radix Puerariae extract. Materials and Methods: Chromatographic separation was performed on a Shiseido CAPCELL PAK C18 analytical column (100 mm × 2.0 mm i.d., 5 μm) by linear gradient elution, with water (0.1% formic acid)-acetonitrile (0.1% formic acid) as mobile phase. Detection was carried out by multiple reaction monitoring (MRM) mode using electrospray ionization in the positive ion mode. Results: The calibration curves were linear over a range of 7.80-1560 ng/mL for puerarin and 6.30-1260 ng/mL for daidzein. The intra- and inter-day precision values were less than 13.6% and their average recoveries was in the range of 77.8% and 88.6% for puerarin and was between 76.3 and 86.8% for daidzein, respectively. Conclusion: The validated method was applied to the comparative pharmacokinetic studies of puerarin and daidzein after oral administration of Gegenqinlian Decoction and Radix Puerariae extract. The pharmacokinetic parameters showed that puerarin and daidzein from Gegenqinlian Decoction were absorbed more effectively with slower elimination in rat plasma than that from Radix Puerariae extract. These results revealed that as far as the Radix Puerariae extract was concerned, it is very valuable to

  16. Influence of processing procedure on the quality of Radix Scrophulariae: a quantitative evaluation of the main compounds obtained by accelerated solvent extraction and high-performance liquid chromatography.

    PubMed

    Cao, Gang; Wu, Xin; Li, Qinglin; Cai, Hao; Cai, Baochang; Zhu, Xuemei

    2015-02-01

    An improved high-performance liquid chromatography with diode array detection combined with accelerated solvent extraction method was used to simultaneously determine six compounds in crude and processed Radix Scrophulariae samples. Accelerated solvent extraction parameters such as extraction solvent, temperature, number of cycles, and analysis procedure were systematically optimized. The results indicated that compared with crude Radix Scrophulariae samples, the processed samples had lower contents of harpagide and harpagoside but higher contents of catalpol, acteoside, angoroside C, and cinnamic acid. The established method was sufficiently rapid and reliable for the global quality evaluation of crude and processed herbal medicines. PMID:25431110

  17. Development and characterization of a three-dimensional radiochromic film stack dosimeter for megavoltage photon beam dosimetry

    SciTech Connect

    McCaw, Travis J. Micka, John A.; DeWerd, Larry A.

    2014-05-15

    Purpose: Three-dimensional (3D) dosimeters are particularly useful for verifying the commissioning of treatment planning and delivery systems, especially with the ever-increasing implementation of complex and conformal radiotherapy techniques such as volumetric modulated arc therapy. However, currently available 3D dosimeters require extensive experience to prepare and analyze, and are subject to large measurement uncertainties. This work aims to provide a more readily implementable 3D dosimeter with the development and characterization of a radiochromic film stack dosimeter for megavoltage photon beam dosimetry. Methods: A film stack dosimeter was developed using Gafchromic{sup ®} EBT2 films. The dosimeter consists of 22 films separated by 1 mm-thick spacers. A Virtual Water™ phantom was created that maintains the radial film alignment within a maximum uncertainty of 0.3 mm. The film stack dosimeter was characterized using simulations and measurements of 6 MV fields. The absorbed-dose energy dependence and orientation dependence of the film stack dosimeter were investigated using Monte Carlo simulations. The water equivalence of the dosimeter was determined by comparing percentage-depth-dose (PDD) profiles measured with the film stack dosimeter and simulated using Monte Carlo methods. Film stack dosimeter measurements were verified with thermoluminescent dosimeter (TLD) microcube measurements. The film stack dosimeter was also used to verify the delivery of an intensity-modulated radiation therapy (IMRT) procedure. Results: The absorbed-dose energy response of EBT2 film differs less than 1.5% between the calibration and film stack dosimeter geometries for a 6 MV spectrum. Over a series of beam angles ranging from normal incidence to parallel incidence, the overall variation in the response of the film stack dosimeter is within a range of 2.5%. Relative to the response to a normally incident beam, the film stack dosimeter exhibits a 1% under-response when the

  18. Characterization of the nanoDot OSLD dosimeter in CT

    PubMed Central

    Scarboro, Sarah B.; Cody, Dianna; Alvarez, Paola; Followill, David; Court, Laurence; Stingo, Francesco C.; Zhang, Di; Kry, Stephen F.

    2015-01-01

    Purpose: The extensive use of computed tomography (CT) in diagnostic procedures is accompanied by a growing need for more accurate and patient-specific dosimetry techniques. Optically stimulated luminescent dosimeters (OSLDs) offer a potential solution for patient-specific CT point-based surface dosimetry by measuring air kerma. The purpose of this work was to characterize the OSLD nanoDot for CT dosimetry, quantifying necessary correction factors, and evaluating the uncertainty of these factors. Methods: A characterization of the Landauer OSL nanoDot (Landauer, Inc., Greenwood, IL) was conducted using both measurements and theoretical approaches in a CT environment. The effects of signal depletion, signal fading, dose linearity, and angular dependence were characterized through direct measurement for CT energies (80–140 kV) and delivered doses ranging from ∼5 to >1000 mGy. Energy dependence as a function of scan parameters was evaluated using two independent approaches: direct measurement and a theoretical approach based on Burlin cavity theory and Monte Carlo simulated spectra. This beam-quality dependence was evaluated for a range of CT scanning parameters. Results: Correction factors for the dosimeter response in terms of signal fading, dose linearity, and angular dependence were found to be small for most measurement conditions (<3%). The relative uncertainty was determined for each factor and reported at the two-sigma level. Differences in irradiation geometry (rotational versus static) resulted in a difference in dosimeter signal of 3% on average. Beam quality varied with scan parameters and necessitated the largest correction factor, ranging from 0.80 to 1.15 relative to a calibration performed in air using a 120 kV beam. Good agreement was found between the theoretical and measurement approaches. Conclusions: Correction factors for the measurement of air kerma were generally small for CT dosimetry, although angular effects, and particularly effects due

  19. Characterization of the nanoDot OSLD dosimeter in CT

    SciTech Connect

    Scarboro, Sarah B.; Cody, Dianna; Followill, David; Court, Laurence; Stingo, Francesco C.; Kry, Stephen F.; Alvarez, Paola; Zhang, Di; McNitt-Gray, Michael

    2015-04-15

    Purpose: The extensive use of computed tomography (CT) in diagnostic procedures is accompanied by a growing need for more accurate and patient-specific dosimetry techniques. Optically stimulated luminescent dosimeters (OSLDs) offer a potential solution for patient-specific CT point-based surface dosimetry by measuring air kerma. The purpose of this work was to characterize the OSLD nanoDot for CT dosimetry, quantifying necessary correction factors, and evaluating the uncertainty of these factors. Methods: A characterization of the Landauer OSL nanoDot (Landauer, Inc., Greenwood, IL) was conducted using both measurements and theoretical approaches in a CT environment. The effects of signal depletion, signal fading, dose linearity, and angular dependence were characterized through direct measurement for CT energies (80–140 kV) and delivered doses ranging from ∼5 to >1000 mGy. Energy dependence as a function of scan parameters was evaluated using two independent approaches: direct measurement and a theoretical approach based on Burlin cavity theory and Monte Carlo simulated spectra. This beam-quality dependence was evaluated for a range of CT scanning parameters. Results: Correction factors for the dosimeter response in terms of signal fading, dose linearity, and angular dependence were found to be small for most measurement conditions (<3%). The relative uncertainty was determined for each factor and reported at the two-sigma level. Differences in irradiation geometry (rotational versus static) resulted in a difference in dosimeter signal of 3% on average. Beam quality varied with scan parameters and necessitated the largest correction factor, ranging from 0.80 to 1.15 relative to a calibration performed in air using a 120 kV beam. Good agreement was found between the theoretical and measurement approaches. Conclusions: Correction factors for the measurement of air kerma were generally small for CT dosimetry, although angular effects, and particularly effects due

  20. Synthesis and characterization of Sm(DBM)3Phen-and Nd(DBM)3Phen-doped polymethylmethacrylate for potential solar spectrum converter

    NASA Astrophysics Data System (ADS)

    Lee, Heungyeol; Yang, Bogeum; Yoo, Mi-Yeon; Lim, Ki-Soo; Lee, Myeongkyu

    2014-07-01

    Sm(DBM)3Phen and Nd(DBM)3Phen were synthesized as stable rare-earth complexes in polymer matrix. Polymethylmethacrylate (PMMA) containing these complexes was highly transparent but exhibited emission peaks in the visible and near-infrared ranges when excited by ultraviolet light. These emission peaks were attributed to energy transfer from excited DBM to rare-earth ions. To evaluate the potential of this material for use in planar solar spectrum converters, complex-doped PMMA layers were solution-casted on top of Si solar cells and their spectral responses were investigated.

  1. The responses of three kinds of passive dosimeters to secondary cosmic rays in the lower atmosphere

    NASA Astrophysics Data System (ADS)

    Yang, Zhen; Chen, Bo; Zhuo, Weihai; Fan, Dunhuang; Zhao, Chao; Zhang, Yu

    2015-12-01

    For accurate measurements of the secondary cosmic rays by using passive dosimeters, the relative responses of the thermoluminescence dosimeter (TLD), optically stimulated luminescence (OSL) dosimeter, and radiophotoluminescent glass dosimeter (RPLGD) were studied. The cosmic-ray shower generator was used to simulate the secondary cosmic rays at the sea level. Monte Carlo simulations were performed to calculate the air kerma and absorbed doses in each kind of dosimeter. The results showed that compared with their responses to gamma rays of 137Cs, the relative responses of the TLD, OSL, and RPLGD were 0.786, 0.707, and 0.735 to the hard component of cosmic rays, respectively, and the values were 0.904, 0.838, and 0.857 to the soft component of cosmic rays, respectively. To verify the simulations results, an in situ measurement with the three kinds of dosimeters was performed at the same place. The results indicated that the secondary cosmic rays monitored with the three kinds of dosimeters were well consistent with each other provided their relative responses were taken into account.

  2. Evaluation of a high exposure solar UV dosimeter for underwater use.

    PubMed

    Schouten, Peter W; Parisi, Alfio V; Turnbull, David J

    2007-01-01

    Solar ultraviolet radiation (UV) is known to have a significant effect upon the marine ecosystem. This has been documented by many previous studies using a variety of measurement methods in aquatic environments such as oceans, streams and lakes. Evidence gathered from these investigations has shown that UVB radiation (280-320 nm) can negatively affect numerous aquatic life forms, while UVA radiation (320-400 nm) can both damage and possibly even repair certain types of underwater life. Chemical dosimeters such as polysulphone have been tested to record underwater UV exposures and in turn quantify the relationship between water column depth and dissolved organic carbon levels to the distribution of biologically damaging UV underwater. However, these studies have only been able to intercept UV exposures over relatively short time intervals. This paper reports on the evaluation of a high exposure UV dosimeter for underwater use. The UV dosimeter was fabricated from poly 2,6-dimethyl-1,4-phenylene oxide (PPO) film. This paper presents the dose response, cosine response, exposure additivity and watermarking effect relating to the PPO dosimeter as measured in a controlled underwater environment and will also detail the overnight dark reaction and UVA and visible radiation response of the PPO dosimeter, which can be used for error correction to improve the reliability of the UV data measured by the PPO dosimeters. These results show that this dosimeter has the potential for long-term underwater UV exposure measurements. PMID:17645666

  3. The responses of three kinds of passive dosimeters to secondary cosmic rays in the lower atmosphere

    SciTech Connect

    Yang, Zhen; Chen, Bo Zhuo, Weihai; Fan, Dunhuang; Zhang, Yu; Zhao, Chao

    2015-12-15

    For accurate measurements of the secondary cosmic rays by using passive dosimeters, the relative responses of the thermoluminescence dosimeter (TLD), optically stimulated luminescence (OSL) dosimeter, and radiophotoluminescent glass dosimeter (RPLGD) were studied. The cosmic-ray shower generator was used to simulate the secondary cosmic rays at the sea level. Monte Carlo simulations were performed to calculate the air kerma and absorbed doses in each kind of dosimeter. The results showed that compared with their responses to gamma rays of {sup 137}Cs, the relative responses of the TLD, OSL, and RPLGD were 0.786, 0.707, and 0.735 to the hard component of cosmic rays, respectively, and the values were 0.904, 0.838, and 0.857 to the soft component of cosmic rays, respectively. To verify the simulations results, an in situ measurement with the three kinds of dosimeters was performed at the same place. The results indicated that the secondary cosmic rays monitored with the three kinds of dosimeters were well consistent with each other provided their relative responses were taken into account.

  4. The responses of three kinds of passive dosimeters to secondary cosmic rays in the lower atmosphere.

    PubMed

    Yang, Zhen; Chen, Bo; Zhuo, Weihai; Fan, Dunhuang; Zhao, Chao; Zhang, Yu

    2015-12-01

    For accurate measurements of the secondary cosmic rays by using passive dosimeters, the relative responses of the thermoluminescence dosimeter (TLD), optically stimulated luminescence (OSL) dosimeter, and radiophotoluminescent glass dosimeter (RPLGD) were studied. The cosmic-ray shower generator was used to simulate the secondary cosmic rays at the sea level. Monte Carlo simulations were performed to calculate the air kerma and absorbed doses in each kind of dosimeter. The results showed that compared with their responses to gamma rays of (137)Cs, the relative responses of the TLD, OSL, and RPLGD were 0.786, 0.707, and 0.735 to the hard component of cosmic rays, respectively, and the values were 0.904, 0.838, and 0.857 to the soft component of cosmic rays, respectively. To verify the simulations results, an in situ measurement with the three kinds of dosimeters was performed at the same place. The results indicated that the secondary cosmic rays monitored with the three kinds of dosimeters were well consistent with each other provided their relative responses were taken into account. PMID:26724019

  5. Monte Carlo simulation of single and two-dosimeter approaches in a steam generator channel head.

    PubMed

    Kim, C H; Reece, W D

    2002-08-01

    In a steam generator channel head, it was not unusual to see radiation workers wearing as many as twelve dosimeters over the surface of the body to avoid a possible underestimation of effective dose equivalent (H(E)) or effective dose (E). This study shows that only one or two dosimeters can be used to estimate H(E) and E without a significant underestimation. MCNP and a point-kernel approach were used to model various exposure situations in a steam generator channel head. The single-dosimeter approach (on the chest) was found to underestimate H(E) and E significantly for a few exposure situations, i.e., when the major portion of radiation source is located in the backside of a radiation worker. In this case, the photons from the source pass through the body and are attenuated before reaching the dosimeter on the chest. To assure that a single dosimeter provides a good estimate of worker dose, these few exposure situations cannot dominate a worker's exposure. On the other hand, the two-dosimeter approach (on the chest and back) predicts H(E) and E very well, hardly ever underestimating these quantities by more than 4% considering all worker positions and contamination situations in a steam generator channel head. This study shows that two dosimeters are adequate for an accurate estimation of H(E) and E in a steam generator channel head. PMID:12132712

  6. Response of TLD-albedo and nuclear track dosimeters exposed to plutonium sources

    SciTech Connect

    Brackenbush, L.W.; Baumgartner, W.V.; Fix, J.J.

    1991-12-01

    Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies have helped assure the accuracy of dosimeters. With the recent change in Hanford`s mission, there has been a significant decrease in the handling of plutonium tetrafluoride, and an increase in the handling of plutonium metal and plutonium oxide sources. This study was initiated to document the performance of the current Hanford TLD-albedo dosimeter under the low scatter conditions of the calibration laboratory and under the high scatter conditions in the work place under carefully controlled conditions at the Plutonium Finishing Plant (PFP). The neutron fields at the PFP facility were measured using a variety of instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters. Various algorithms were used to evaluate the TLD-albedo dosimeters, and the results are given in this report. Using current algorithms, the dose equivalents evaluated for bare sources and sources with less than 2.5 cm (1 in.) of acrylic plastic shielding in high scatter conditions typical of glove box operations are reasonably accurate. Recently developed CR-39 track etch dosimeters (TEDs) were also exposed in the calibration laboratory and at the PFP. The results indicate that the TED dosimeters are quite accurate for both bare and moderated neutron sources. Until personnel dosimeter is available that incorporates a direct measure of the neutron dose to a person, technical uncertainties in the accuracy of the recorded data will continue.

  7. Response of TLD-albedo and nuclear track dosimeters exposed to plutonium sources

    SciTech Connect

    Brackenbush, L.W.; Baumgartner, W.V.; Fix, J.J.

    1991-12-01

    Neutron dosimetry has been extensively studied at Hanford since the mid-1940s. At the present time, Hanford contractors use thermoluminescent dosimeter (TLD)-albedo dosimeters to record the neutron dose equivalent received by workers. The energy dependence of the TLD-albedo dosimeter has been recognized and documented since introduced at Hanford in 1964 and numerous studies have helped assure the accuracy of dosimeters. With the recent change in Hanford's mission, there has been a significant decrease in the handling of plutonium tetrafluoride, and an increase in the handling of plutonium metal and plutonium oxide sources. This study was initiated to document the performance of the current Hanford TLD-albedo dosimeter under the low scatter conditions of the calibration laboratory and under the high scatter conditions in the work place under carefully controlled conditions at the Plutonium Finishing Plant (PFP). The neutron fields at the PFP facility were measured using a variety of instruments, including a multisphere spectrometer, tissue equivalent proportional counters, and specially calibrated rem meters. Various algorithms were used to evaluate the TLD-albedo dosimeters, and the results are given in this report. Using current algorithms, the dose equivalents evaluated for bare sources and sources with less than 2.5 cm (1 in.) of acrylic plastic shielding in high scatter conditions typical of glove box operations are reasonably accurate. Recently developed CR-39 track etch dosimeters (TEDs) were also exposed in the calibration laboratory and at the PFP. The results indicate that the TED dosimeters are quite accurate for both bare and moderated neutron sources. Until personnel dosimeter is available that incorporates a direct measure of the neutron dose to a person, technical uncertainties in the accuracy of the recorded data will continue.

  8. An NMR relaxometry and gravimetric study of gelatin-free aqueous polyacrylamide dosimeters

    NASA Astrophysics Data System (ADS)

    Babic, Steven; Schreiner, L. John

    2006-09-01

    In conformal radiation therapy, a high dose of radiation is given to a target volume to increase the probability of cure, and care is taken to minimize the dose to surrounding healthy tissue. The techniques used to achieve this are very complicated and the precise verification of the resulting three-dimensional (3D) dose distribution is required. Polyacrylamide gelatin (PAG) dosimeters with magnetic resonance imaging and optical computed tomography scanning provide the required 3D dosimetry with high spatial resolution. Many basic studies have characterized these chemical dosimeters that polymerize under irradiation. However, the investigation of the fundamental properties of the radiation-induced polymerization in PAG dosimeters is complicated by the presence of the background gelatin matrix. In this work, a gelatin-free model system for the study of the basic radiation-induced polymerization in PAG dosimeters has been developed. Experiments were performed on gelatin-free dosimeters, named aqueous polyacrylamide (APA) dosimeters, containing equal amounts of acrylamide and N,N'-methylene-bisacrylamide. The APA dosimeters were prepared with four different total monomer concentrations (2, 4, 6 and 8% by weight). Nuclear magnetic resonance (NMR) spin-spin and spin-lattice proton relaxation measurements at 20 MHz, and gravimetric analyses performed on all four dosimeters, show a continuous degree of polymerization over the dose range of 0-25 Gy. The developed NMR model explains the relationship observed between the relaxation data and the amount of crosslinked polymer formed at each dose. This model can be extended with gelatin relaxation data to provide a fundamental understanding of radiation-induced polymerization in the conventional PAG dosimeters.

  9. Thermoluminescent dosimeter measurements and analysis for LDEF experiment M0006

    NASA Technical Reports Server (NTRS)

    Stauber, Michael C.; Chang, J.; Kantorcik, T.

    1991-01-01

    Glow curve measurements are reported up to 600 C of (Thermoluminescent Dosimeter Measurement) TLD-100 (LiF) samples deployed on Long Duration Exposure Facility (LDEF) and retained as ground control. Lab exposure simulations are also reported with Co-60 radiation, low energy light ions and high energy protons in an effort to replicate the glow curves, especially the high temperature peaks observed in the LDEF TLD specimens. The evidence to date clearly shows the effect of inflight anneal on the low temperature part of the glow curve. It also shows that the high temperature part of the glow curve appears due to ion dose deposition. Initial correlations between high temperature glow peaks and effective LET of the registered dose is given.

  10. Applicability of the Sunna dosimeter for food irradiation control

    NASA Astrophysics Data System (ADS)

    Kovács, A.; Baranyai, M.; Wojnárovits, L.; Miller, S.; Murphy, M.; McLaughlin, W. L.; Slezsák, I.; Kovács, A. I.

    2002-03-01

    The quick development concerning the commercial application of food irradiation in the USA recently resulted in growing marketing of irradiated red meat as well as irradiated fresh and dried fruits. These gamma and electron irradiation technologies require specific dosimetry systems for process control. The new version of the Sunna dosimeter has been characterized in gamma, electron and bremsstrahlung radiation fields by measuring the optically stimulated luminescence (osl) at 530 nm both below and above 1 kGy, i.e. for disinfestation and for meat irradiation purposes. No humidity and no significant dose rate effect on the green osl signal was observed. The temperature coefficient was determined from 0°C up to about 40°C and to stabilize the osl signal after irradiation a heat treatment method was introduced. Based on these investigations the Sunna 'gamma' film is a suitable candidate for dose control below and above 1 kGy for food irradiation technologies.

  11. Review of four novel dosimeters developed for use in radiotherapy

    NASA Astrophysics Data System (ADS)

    Metcalfe, P.; Quinn, A.; Loo, K.; Lerch, M.; Petasecca, M.; Wong, J.; Hardcastle, N.; Carolan, M.; McNamara, J.; Cutajar, D.; Fuduli, I.; Espinoza, A.; Porumb, C.; Rosenfeld, A.

    2013-06-01

    Centre for Medical Radiation Physics (CMRP) is a research strength at the University of Wollongong, the main research theme of this centre is to develop prototype novel radiation dosimeters. Multiple detector systems have been developed by Prof Rosenfelds' group for various radiation detector applications. This paper focuses on four current detector systems being developed and studied at CMRP. Two silicon array detectors include the magic plate and dose magnifying glass (DMG), the primary focus of these two detectors is high spatial and temporal resolution dosimetry in intensity modulated radiation therapy (IMRT) beams. The third detector discussed is the MOSkinTM which is a high spatial resolution detector based on MOSFET technology, its primary role is in vivo dosimetry. The fourth detector system discussed is BrachyView, this is a high resolution dose viewing system based on Medipix detector technology.

  12. A Radiation Dosimeter Concept for the Lunar Surface Environment

    NASA Technical Reports Server (NTRS)

    Adams, James H.; Christl, Mark J.; Watts, John; Kuznetsov, Eugeny N.; Parnell, Thomas A.; Pendleton, Geoff N.

    2007-01-01

    A novel silicon detector configuration for radiation dose measurements in an environment where solar energetic particles are of most concern is described. The dosimeter would also measure the dose from galactic cosmic rays. In the lunar environment a large range in particle flux and ionization density must be measured and converted to dose equivalent. This could be accomplished with a thick (e.g. 2mm) silicon detector segmented into cubic volume elements "voxels" followed by a second, thin monolithic silicon detector. The electronics needed to implement this detector concept include analog signal processors (ASIC) and a field programmable gate array (FPGA) for data accumulation and conversion to linear energy transfer (LET) spectra and to dose-equivalent (Sievert). Currently available commercial ASIC's and FPGA's are suitable for implementing the analog and digital systems.

  13. Solid state dosimeters used in medical physics "A review"

    NASA Astrophysics Data System (ADS)

    Azorín-Nieto, Juan

    2012-10-01

    Many solid-state detectors have been successfully used to perform the quality control and in vivo dosimetry in medical physics, both in diagnostic radiology and radiotherapy, as they have high sensitivity in a small volume; most of them do not require electrical connection and have dosimetric characteristics of interest such as: good accuracy and reproducibility, as well as a response independent of the energy of radiation, some of them. For this reason, the selection of an appropriate detector for use in medical physics must take into account the energy mass absorption coefficient relative to water for photon sources and the mass stopping power relative to water for beta emitters and electron beams in the energy range of interest in medical physics, as well as the effective atomic number of materials that constitute them. This paper presents a review of the dosimetric characteristics of the solid state dosimeters most suitable for use in medical physics.

  14. Stereotactic radiosurgery dosimetry using thermoluminescent dosimeters and radiochromic films

    NASA Astrophysics Data System (ADS)

    Ávila-Rodríguez, Miguel A.; Rodríguez-Villafuerte, Mercedes; Perches, Rodolfo Díaz

    2000-10-01

    In this work we present a protocol to measure absorbed dose distributions in stereotactic radiosurgery treatments with a linear accelerator (Linac) using thermoluminescent dosimeters (TLD) and radiochromic dye films. A Linac Philips SL-15 (6 MV X-rays), a ZD2 stereoactic system for localizing the target via computed tomography (CT), and Leibinger radiosurgery accessories will be used. A versatile spherical acrylic phantom of 16 cm diameter to measure the dose distributions has been designed. The phantom is composed of two hemispheres. On one flat side of the hemispheres an array of Harshaw/Bicron TLD-100 or a sheet of GafChromic MD-55 film will be placed. The phantom will be irradiated in three different orientations to obtain spatial dose distributions in the coronal, sagital and transverse planes. The experimental measurement will be compared with the results provided by a commercial treatment-planning system.

  15. [AOR characterization and zoning: a dosimeter for blue light].

    PubMed

    Dario, R; Uva, J; Di Lecce, V; Quarto, A

    2011-01-01

    The paper presents the results obtained thanks to an innovative experimental device for the assessment of artificial optical radiation (AOR) exposure in workplace. This . device was developed by 'Politecnico di Bari-DIASS'. The wearable personal dosimeter has three sensors: one is used for measuring head position/movement, therefore there is a color light sensor to determine the AOR and finally there is a video camera to localize sources. Our system is connected to a netbook via USB cable that allows one to obtain the real and extimated value of worker's exposure, also with "augmented reality". The aim of this paper is realizing work place safety zoning for the classifacation of not only specific dangerous areas through the analysis of overlapping information from the device. PMID:23393888

  16. Calibration results obtained with Liulin-4 type dosimeters

    NASA Astrophysics Data System (ADS)

    Dachev, Ts.; Tomov, B.; Matviichuk, Yu.; Dimitrov, Pl.; Lemaire, J.; Gregoire, Gh.; Cyamukungu, M.; Schmitz, H.; Fujitaka, K.; Uchihori, Y.; Kitamura, H.; Reitz, G.; Beaujean, R.; Petrov, V.; Shurshakov, V.; Benghin, V.; Spurny, F.

    The Mobile Radiation Exposure Control System's (Liulin-4 type) main purpose is to monitor simultaneously the doses and fluxes at 4 independent places. It can also be used for personnel dosimetry. The system consists of 4 battery-operated 256-channel dosimeters-spectrometers. We describe results obtained during the calibrations of the spectrometers at the Cyclotron facilities of the University of Louvain, Belgium and of the National Institute of Radiological Sciences-STA, Chiba, Japan with protons of energies up to 70 MeV. The angular sensitivities of the devices are studied and compared with Monte-Carlo predictions. We also present the results obtained at the HIMAC accelerator with 500 MeV/u Fe ions and at the CERN high energy radiation reference fields. Records made during airplane flights are shown and compared with the predictions of the CARI-6 model.

  17. Effect of Dipsaci radix on hind limb muscle atrophy of sciatic nerve transected rats.

    PubMed

    Jung, Hyuk-Sang; Noh, Chung-Ku; Ma, Sun-Ho; Hong, Eun Ki; Sohn, Nak-Won; Kim, Yoon-Bum; Kim, Sung-Hoon; Sohn, Youngjoo

    2009-01-01

    It was reported that Dipsaci radix (DR) has a reinforcement effect on the bone-muscle dysfunction in the oriental medical classics and the experimental animal studies. The muscle atrophy was induced by unilateral transection of the sciatic nerve of the rats. Water-extract of DR was used as treatment once a day for 12 days. The muscle weights of the hind limb, atrophic changes, glycogen contents, compositions and cross-section areas of muscle fiber types in soleus and medial gastrocnemius were investigated. Muscle fiber type was classified to type-I and type-II with MHCf immunohistochemistry. Furthermore, Bax and Bcl-2 expressions were observed with immunohistochemiatry. DR treatment significantly increased muscle weights of soleus, medial gastrocnemius, lateral gastrocnemius, and posterior tibialis of the damaged hind limb. DR treatment reduced apoptotic muscle nuclei and hyaline-degenerated muscle fibers in soleus and medial gastrocnemius of the damaged hind limb. DR treatment also significantly increased glycogen contents in medial gastrocnemius of the damaged hind limb. DR treatment significantly attenuated the slow-to-fast shift in soleus of the damaged hind limb but not in medial gastrocnemius. DR treatment significantly increased cross-section areas of type-I and type-II fibers in soleus and medial gastrocnemius of the damaged hind limb. In soleus and medial gastrocnemius, DR treatment significantly reduced Bax positive muscle nuclei in the damaged hind limb. These results suggest that DR treatment has an anti-atrophic effect and an anti-apoptotic effect against myonuclear apoptosis induced by the peripheral nerve damage. PMID:19938217

  18. Luteimonas terrae sp. nov., isolated from rhizosphere soil of Radix ophiopogonis.

    PubMed

    Ngo, Hien T T; Yin, Chang Shik

    2016-05-01

    A Gram-staining-negative, strictly aerobic, rod-shaped and bright-yellow-pigmented bacterium, motile by means of a single polar flagellum, designated THG-MD21T, was isolated from rhizosphere soil of Radix ophiopogonis in Henan province, PR China. On the basis of 16S rRNA gene sequence similarity, strain THG-MD21T belongs to the genus Luteimonas and was most closely related to Luteimonas aestuarii B9T (98.2 % sequence similarity), Lysobacter panaciterrae Gsoil 068T (97.2 %) and Luteimonas marina FR1330T (97.0 %). The DNA G+C content was 64.4 mol%. The DNA-DNA relatedness between strain THG-MD21T and its closest phylogenetic neighbours was below 30.0 %. The only isoprenoid quinone detected in strain THG-MD21T was ubiquinone-8.The major polar lipids were found to be phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol, and the predominant fatty acids were iso-C11 : 0, iso-C15 : 0, iso-C16 : 0, C16 : 0 and iso-C17 : 1ω9c. The DNA-DNA hybridization result and characteristics revealed by a polyphasic study showed that strain THG-MD21T represents a novel species, for which the name Luteimonas terrae sp. nov. is proposed. The type strain is THG-MD21T ( = KACC 18131T = JCM 30122T). PMID:26782356

  19. Effects of the inhaled treatment of liriope radix on an asthmatic mouse model.

    PubMed

    Kim, Ki-Suk; Cho, Dong-Hyuk; Yang, Hea Jung; Choi, Eun-Kyeong; Shin, Min Hee; Kim, Kang-Hoon; Ahn, Kwang Seok; Ha, In Jin; Na, Yun-Cheol; Um, Jae Young; Chung, Won Seok; Jung, Hee-Jae; Jung, Sung-Ki; Jang, Hyeung-Jin

    2015-01-01

    As a treatment for allergic asthma, inhaled treatments such as bronchodilators that contain β2-agonists have an immediate effect, which attenuates airway obstructions and decreases airway hypersensitivity. However, bronchodilators only perform on a one off basis, but not consistently. Asthma is defined as a chronic inflammatory disease of the airways accompanying the overproduction of mucus, airway wall remodeling, bronchial hyperreactivity and airway obstruction. Liriope platyphylla radix extract (LPP), a traditional Korean medicine, has been thoroughly studied and found to be an effective anti-inflammatory medicine. Here, we demonstrate that an inhaled treatment of LPP can attenuate airway hyperresponsiveness (AHR) in an ovalbumin-induced asthmatic mouse model, compared to the saline-treated group (p < 0.01). Moreover, LPP decreases inflammatory cytokine levels, such as eotaxin (p < 0.05), IL-5 (p < 0.05), IL-13 (p < 0.001), RANTES (p < 0.01), and TNF-α (p < 0.05) in the bronchoalveolar lavage (BAL) fluid of asthmatic mice. A histopathological study was carried out to determine the effects of LPP inhalation on mice lung tissue. We performed UPLC/ESI-QTOF-MS, LC/MS, and GC/MS analyses to analyze the chemical constituents of LPP, finding that these are ophiopogonin D, spicatoside A, spicatoside B, benzyl alcohol, and 5-hydroxymethylfurfural. This study demonstrates the effect of an inhaled LPP treatment both on airway AHR and on the inflammatory response in an asthmatic mouse model. Hence, LPP holds significant promise as a nasal inhalant for the treatment of asthmatic airway disease. PMID:25967662

  20. Influence of Trichobilharzia regenti (Digenea: Schistosomatidae) on the Defence Activity of Radix lagotis (Lymnaeidae) Haemocytes

    PubMed Central

    Skála, Vladimír; Černíková, Alena; Jindrová, Zuzana; Kašný, Martin; Vostrý, Martin; Walker, Anthony J.; Horák, Petr

    2014-01-01

    Radix lagotis is an intermediate snail host of the nasal bird schistosome Trichobilharzia regenti. Changes in defence responses in infected snails that might be related to host-parasite compatibility are not known. This study therefore aimed to characterize R. lagotis haemocyte defence mechanisms and determine the extent to which they are modulated by T. regenti. Histological observations of R. lagotis infected with T. regenti revealed that early phases of infection were accompanied by haemocyte accumulation around the developing larvae 2–36 h post exposure (p.e.) to the parasite. At later time points, 44–92 h p.e., no haemocytes were observed around T. regenti. Additionally, microtubular aggregates likely corresponding to phagocytosed ciliary plates of T. regenti miracidia were observed within haemocytes by use of transmission electron microscopy. When the infection was in the patent phase, haemocyte phagocytic activity and hydrogen peroxide production were significantly reduced in infected R. lagotis when compared to uninfected counterparts, whereas haemocyte abundance increased in infected snails. At a molecular level, protein kinase C (PKC) and extracellular-signal regulated kinase (ERK) were found to play an important role in regulating these defence reactions in R. lagotis. Moreover, haemocytes from snails with patent infection displayed lower PKC and ERK activity in cell adhesion assays when compared to those from uninfected snails, which may therefore be related to the reduced defence activities of these cells. These data provide the first integrated insight into the immunobiology of R. lagotis and demonstrate modulation of haemocyte-mediated responses in patent T. regenti infected snails. Given that immunomodulation occurs during patency, interference of snail-host defence by T. regenti might be important for the sustained production and/or release of infective cercariae. PMID:25372492

  1. Simultaneous quantification and pharmacokinetics of alkaloids in Herba Ephedrae-Radix Aconiti Lateralis extracts.

    PubMed

    Song, Shuai; Tang, Qingfa; Huo, Huiling; Li, Hancheng; Xing, Xuefeng; Luo, Jiabo

    2015-01-01

    The combination of Herba Ephedrae (Mahuang in Chinese) and Radix Aconiti Lateralis (Fuzi in Chinese) is a classical preparation in traditional Chinese medicine and used for treating colds and rheumatic arthralgia. However, herbal medicines containing ephedrines and Aconitum alkaloids are strictly regulated because of the potential for adverse effects on the cardiovascular system and the central nervous system. We aimed to investigate the pharmacokinetics of 11 alkaloids in the Mahuang-Fuzi combination and single-herb extracts after oral administration in rats. The alkaloids were norephedrine, norpseudoephedrine, ephedrine, pseudoephedrine, methylephedrine, aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine. Simultaneous determination of the alkaloids, including two pairs of diastereomers, was achieved in 14.5 min by a simple, rapid and sensitive ultra-performance liquid chromatography-tandem mass spectrometry method. The separation was performed on a Zorbax SB-Aq column (100 mm × 2.1 mm, 3.5 μm) at a flow rate of 0.3 mL/min using acetonitrile-0.1% formic acid aqueous solution as the mobile phase. The validated method demonstrated adequate sensitivity, selectivity and process efficiency for the quantitative analysis of complex herbal components. Compared with single-herb extracts, alkaloids in plasma (except methylephedrine, benzoylmesaconine and benzoylhypaconine) showed slower elimination (the mean residence time or half-life was longer), although the maximum plasma concentration and area under the plasma concentration curve values decreased. Accumulation may occur with continuous drug intake. These results suggest that drug monitoring may be essential for the safe use of the Mahuang-Fuzi combination. PMID:25324527

  2. Comparison of Puerariae Radix and its hydrolysate on stimulation of hyaluronic acid production in NHEK cells.

    PubMed

    Wen, Kuo-Ching; Lin, Shiuan-Pey; Yu, Chung-Ping; Chiang, Hsiu-Mei

    2010-01-01

    Hyaluronic acid (HA) is present in high concentrations in the intercellular spaces of the epidermis and the connective tissues of the dermis. It is associated with many beneficial biological activities including water retention, maintenance of various cellular functions, and skin homeostasis. Puerariae Radix (PR), a Chinese herb and a popular food in Asia, is used for various medicinal purposes including anti-hypertension, anti-angina pectoris and anti-dipsotropic. PR is rich in isoflavone glycosides like genistin and daidzin as soya. In this study, Bifidobactericum breve CCRC 14061 and CCRC 11846 were used for the fermentation of PR; moreover, acid was used to hydrolyze PR decoction. Genistein and daidzein in the hydrolysate were determined by HPLC. The HA production in normal human epidermal keratinocytes (NHEK) was measured after 48 hours incubation with PR and its hydrolysate, respectively. HA was assayed by enzyme-linked immunosorbent assay (ELISA), and retinoic acid was used as the positive control. After fermentation with Bifidobactericum breve, the contents of daidzein and genistein were increased 785% and 1,010% by CCRC 14061, and 192% and 406% by CCRC 11846, respectively, whereas after acid hydrolysis, only daidzein was increased by 990%. The production of HA in NHEK was increased after incubation with the fermentation product of CCRC 14061, acid hydrolysate, PR decoction and retinoic acid (22+/- 0.2%), whereas no increase of HA concentration was found after incubation with the fermentation product of CCRC 11846. Furthermore, the PR hydrolysate stimulated the HA production of NHEK, and the effect was dose-dependent (18.6%-83.9%). In conclusion, PR preparations would stimulate HA production in NHEK cells which might be used as a new cosmetic ingredient in moisturizers and an anti-aging agent. PMID:20128051

  3. Simultaneous Determination of 10 Flavonoids in Crude and Wine-Processed Radix scutellariae by UHPLC.

    PubMed

    Cui, Xiaobing; Cai, Hao; Li, Huaning; Tao, Yi; Huang, Ping; Qian, Xiaocui; Li, Junsong; Cai, Baochang

    2016-03-01

    Radix scutellariae is a well-known traditional Chinese medicine used for the treatments of inflammation, pyrexia, hepatitis, etc. Flavonoids are its main active compounds. The aim of this study is to develop and validate the ultra high-performance liquid chromatography (UHPLC) method for simultaneous determination of 10 flavonoids (baicalin, wogonoside, baicalein, wogonin, oroxylin A, chrysin, scutellarin, oroxylin A-7-O-glucuronide, apigenin and apigenin-7-glucuronide) in crude and wine-processed R. scutellariae. The quantitative determination was conducted by UHPLC. Optimal separation was achieved by gradient elution with mobile phase consisting of 0.01% aqueous formic acid and methanol on a Waters ACQUITY UHPLC BEH C18 column. Detection wavelength was set at 275 nm. Method validation was accomplished with linearity, precision and recovery tests. All calibration curves showed good linearity (R(2) > 0.9993). The limit of detection and limit of quantification of these compounds were from 0.08 to 0.24 µg/mL and from 0.23 to 0.76 µg/mL, respectively. The average recoveries of these compounds were from 96.95 to 109.51% with relative standard deviation (RSD) values from 2.14 to 3.26% for crude R. scutellariae, while from 94.73 to 108.38% with RSD values from 1.83 to 3.47% for wine-processed R. scutellariae. The developed method can be applied to the intrinsic quality control of crude and wine-processed R. scutellariae. PMID:26400954

  4. Effects of Linderae radix extracts on a rat model of alcoholic liver injury

    PubMed Central

    WANG, JUN-WEI; CHEN, XIN-YI; HU, PEI-YANG; TAN, MING-MING; TANG, XIAO-GANG; HUANG, MIN-CONG; LOU, ZHAO-HUAN

    2016-01-01

    Traditional treatments have a poor effect on alcoholic liver diseases. Linderae radix (LR), the dried root of Lindera aggregata (Sims) Kosterm., has been frequently used in traditional Chinese medicine for treating various diseases, and has been shown to exhibit a protective effect on liver injury. In the present study, LR extracts were made using various solvents, and then administrated to rats to establish a model of ethanol-induced liver injury. The study aimed to investigate the therapeutic effects and potential mechanism of LR extracts on acute alcoholic liver injury. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycercide (TG), cholesterol (TC), methane dicarboxylic aldehyde (MDA) and superoxide dismutase (SOD) were determined using an automatic biochemistry analyzer. In addition, pathological examination was performed by hematoxylin-eosin staining. The levels of MDA and SOD, and the expression levels of nuclear factor (NF)-κB, tumor necrosis factor (TNF)-α and interleukin (IL)-1β in liver tissue were investigated immunohistochemically. The expression of cytochrome P450 2E1 (CYP2E1) mRNA was quantified by reverse transcription-quantitative polymerase chain reaction. The results indicated that LR extracts improved the histopathological status and decreased the serum levels of ALT, AST, TG, TC and MDA. Furthermore, the levels of MDA and inflammatory mediators (NF-κB, TNF-α and IL-1β) were decreased in liver tissues, and the overexpression of CYP2E1 mRNA induced by ethanol treatment. LR extracts exhibited a protective effect on alcoholic liver injury and the mechanism may be associated with the anti-inflammatory and anti-oxidative action. PMID:27313665

  5. Anti-Inflammatory Effect of Combination of Scutellariae Radix and Liriopis Tuber Water Extract

    PubMed Central

    So, Mi-Hye; Choi, You-Kyung

    2015-01-01

    Scutellariae Radix and Liriopis Tuber have been used to treat the inflammatory diseases in traditional Korean medicine and anti-inflammatory effect of each herb has been shown partially in several articles. However, the combined extract of these medicinal herbs (SL) has not been reported for its anti-inflammatory effects. In this study, we investigated the effects of SL on the creation of several proinflammatory mediators in RAW 264.7 cell mouse macrophages induced by Lipopolysaccharide (LPS). SL inhibited significantly the increase of NO, the release of intracellular calcium, the increase of interleukin-6 (IL-6), macrophage inflammatory proteins (MIP-1α, MIP-1β, and MIP-2), and granulocyte colony-stimulating factor (G-CSF) in LPS-induced RAW 264.7 cell at the concentrations of 25, 50, and 100 μg/mL, and SL inhibited significantly the increase of macrophage colony-stimulating factor (M-CSF) at the concentrations of 25 and 50 μg/mL, and tumor necrosis factor (TNF) at the concentration of 25 μg/mL. These results implicate that SL has anti-inflammatory effects by suppressing the production of various inflammatory mediators in macrophages. But SL did not inhibit significantly the increase of granulocyte macrophage colony-stimulating factor (GM-CSF), leukemia inhibitory factor (LIF), and Regulated on Activation, Normal T cell Expressed and Secreted (RANTES); therefore, further study is demanded for the follow-up research to find out the possibility of SL as a preventive and therapeutic medicine for various inflammatory diseases. PMID:26604969

  6. Calibration factors for the SNOOPY NP-100 neutron dosimeter

    NASA Astrophysics Data System (ADS)

    Moscu, D. F.; McNeill, F. E.; Chase, J.

    2007-10-01

    Within CANDU nuclear power facilities, only a small fraction of workers are exposed to neutron radiation. For these individuals, roughly 4.5% of the total radiation equivalent dose is the result of exposure to neutrons. When this figure is considered across all workers receiving external exposure of any kind, only 0.25% of the total radiation equivalent dose is the result of exposure to neutrons. At many facilities, the NP-100 neutron dosimeter, manufactured by Canberra Industries Incorporated, is employed in both direct and indirect dosimetry methods. Also known as "SNOOPY", these detectors undergo calibration, which results in a calibration factor relating the neutron count rate to the ambient dose equivalent rate, using a standard Am-Be neutron source. Using measurements presented in a technical note, readings from the dosimeter for six different neutron fields in six source-detector orientations were used, to determine a calibration factor for each of these sources. The calibration factor depends on the neutron energy spectrum and the radiation weighting factor to link neutron fluence to equivalent dose. Although the neutron energy spectra measured in the CANDU workplace are quite different than that of the Am-Be calibration source, the calibration factor remains constant - within acceptable limits - regardless of the neutron source used in the calibration; for the specified calibration orientation and current radiation weighting factors. However, changing the value of the radiation weighting factors would result in changes to the calibration factor. In the event of changes to the radiation weighting factors, it will be necessary to assess whether a change to the calibration process or resulting calibration factor is warranted.

  7. Thermal drift reduction with multiple bias current for MOSFET dosimeters.

    PubMed

    Carvajal, M A; Martínez-Olmos, A; Morales, D P; Lopez-Villanueva, J A; Lallena, A M; Palma, A J

    2011-06-21

    New thermal compensation methods suitable for p-channel MOSFET (pMOS) dosimeters with the usual dose readout procedure based on a constant drain current are presented. Measuring the source-drain voltage shifts for two or three different drain currents and knowing the value of the zero-temperature coefficient drain current, I(ZTC), the thermal drift of source-drain or threshold voltages can be significantly reduced. Analytical expressions for the thermal compensation have been theoretically deduced on the basis of a linear dependence on temperature of the parameters involved. The proposed thermal modelling has been experimentally proven. These methods have been applied to a group of ten commercial pMOS transistors (3N163). The thermal coefficients of the source-drain voltage and the threshold voltage were reduced from -3.0 mV  °C(-1), in the worst case, down to -70 µV  °C(-1). This means a thermal drift of -2.4 mGy  °C(-1) for the dosimeter. When analysing the thermal drifts of all the studied transistors, in the temperature range from 19 to 36 °C, uncertainty was obtained in the threshold voltage due to a thermal drift of ±9 mGy (2 SD), a commonly acceptable value in most radiotherapy treatments. The procedures described herein provide thermal drift reduction comparable to that of other technological or numerical strategies, but can be used in a very simple and low-cost dosimetry sensor. PMID:21606552

  8. New technique to improve the accuracy of albedo neutron dosimeter evaluations

    NASA Astrophysics Data System (ADS)

    Hankins, D. E.

    The calibration factor for albedo neutron dosimeters varies greatly depending upon the energy of the neutrons in the exposure. Calibration results obtained over an eight-year period at each Lawrence Livermore National Laboratory facility where neutron exposure may occur were reviewed. A stronger relationship than expected was found between the ratio of the readings of the 9-in. to 3-in. spheres and the percent thermal. Readings from personnel and albedo badges were reviewed. The readings were consistent with the use of a calibration factor for the albedo dosimeter which varies with changes in the ratio of the personnel and albedo dosimeter TLD readings.

  9. Laboratory facilities and recommendations for the characterization of biological ultraviolet dosimeters.

    PubMed

    Bolsée, D; Webb, A R; Gillotay, D; Dörschel, B; Knuschke, P; Krins, A; Terenetskaya, I

    2000-06-01

    A laboratory facility for characterizing biological dosimeters for the measurement of UV radiation has been built and tested. The facility is based on a solar simulator, stabilized by photofeedback, and monitored by a spectroradiometer, with a versatile filter arrangement. This enables the following characteristics of the dosimeters to be ascertained: spectral response, linearity, and reciprocity; angular acceptance and response; calibration in simulated sunlight. The system has been tested on a variety of dosimeters and has the potential to be used with other radiometers, subject currently to the size of their active surface. PMID:18345205

  10. Measurement of a 200 MeV proton beam using a polyurethane dosimeter

    NASA Astrophysics Data System (ADS)

    Heard, Malcolm; Adamovics, John; Ibbott, Geoffrey

    2006-12-01

    PRESAGETM (Heuris Pharma LLC, Skillman, NJ) is a three-dimensional polyurethane dosimeter containing a leuco dye that generates a color change when irradiated. The dosimeter is solid and does not require a container to maintain its shape. The dosimeter is transparent before irradiation and the maximum absorbance of the leuco dye occurs at 633 nm which is compatible with the OCT-OPUSTM laser CT scanner (MGS Research, Inc., Madison, CT). The purpose of this study was to investigate the response of PRESAGETM to proton beam radiotherapy.

  11. New technique to improve the accuracy of albedo neutron dosimeter evaluations

    SciTech Connect

    Hankins, D.E.

    1984-01-01

    The calibration factor for albedo neutron dosimeters varies greatly depending upon the energy of the neutrons in the exposure. Calibration results obtained over an eight-year period at each Lawrence Livermore National Laboratory facility where neutron exposure may occur were reviewed. A stronger relationship than expected was found between the ratio of the readings of the 9-in. to 3-in. spheres and the percent thermal. Readings from personnel and albedo badges were reviewed. The readings were consistent with the use of a calibration factor for the albedo dosimeter which varies with changes in the ratio of the personnel and albedo dosimeter TLD readings. 2 references, 6 figures. (ACR)

  12. Kai-Xin-San, a Chinese Herbal Decoction Containing Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria, Stimulates the Expression and Secretion of Neurotrophic Factors in Cultured Astrocytes

    PubMed Central

    Zhu, Kevin Yue; Xu, Sherry Li; Choi, Roy Chi-Yan; Yan, Artemis Lu; Dong, Tina Ting-Xia; Tsim, Karl Wah-Keung

    2013-01-01

    Kai-xin-san (KXS), a Chinese herbal decoction prescribed by Sun Simiao in Beiji Qianjin Yaofang about 1400 years ago, contains Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria. In China, KXS has been used to treat stress-related psychiatric diseases with the symptoms of depression and forgetfulness. Although animal study has supported the antidepression function of KXS, the mechanism in cellular level is still unknown. Here, a chemically standardized water extract of KXS was applied onto cultured astrocytes in exploring the action mechanisms of KXS treatment, which significantly stimulated the expression and secretion of neurotrophic factors, including NGF, BDNF, and GDNF, in a dose-dependent manner: the stimulation was both in mRNA and protein levels. In addition, the water extracts of four individual herbs did not significantly stimulate the expression of neurotrophic factors, which could explain the optimized effect of KXS in a herbal decoction. The KXS-induced expression of neurotrophic factors did not depend on signaling mediated by estrogen receptor or protein kinase. The results suggested that the antidepressant-like action of KXS might be mediated by an increase of expression of neurotrophic factors in astrocytes, which fully supported the clinical usage of this decoction. PMID:24222781

  13. Kai-xin-san, a chinese herbal decoction containing ginseng radix et rhizoma, polygalae radix, acori tatarinowii rhizoma, and poria, stimulates the expression and secretion of neurotrophic factors in cultured astrocytes.

    PubMed

    Zhu, Kevin Yue; Xu, Sherry Li; Choi, Roy Chi-Yan; Yan, Artemis Lu; Dong, Tina Ting-Xia; Tsim, Karl Wah-Keung

    2013-01-01

    Kai-xin-san (KXS), a Chinese herbal decoction prescribed by Sun Simiao in Beiji Qianjin Yaofang about 1400 years ago, contains Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria. In China, KXS has been used to treat stress-related psychiatric diseases with the symptoms of depression and forgetfulness. Although animal study has supported the antidepression function of KXS, the mechanism in cellular level is still unknown. Here, a chemically standardized water extract of KXS was applied onto cultured astrocytes in exploring the action mechanisms of KXS treatment, which significantly stimulated the expression and secretion of neurotrophic factors, including NGF, BDNF, and GDNF, in a dose-dependent manner: the stimulation was both in mRNA and protein levels. In addition, the water extracts of four individual herbs did not significantly stimulate the expression of neurotrophic factors, which could explain the optimized effect of KXS in a herbal decoction. The KXS-induced expression of neurotrophic factors did not depend on signaling mediated by estrogen receptor or protein kinase. The results suggested that the antidepressant-like action of KXS might be mediated by an increase of expression of neurotrophic factors in astrocytes, which fully supported the clinical usage of this decoction. PMID:24222781

  14. Exploring Potential Chemical Transformation by Chemical Profiling Approach for Rapidly Evaluating Chemical Consistency between Sun-Dried and Sulfur-Fumigated Radix Paeoniae Alba Using Ultraperformance Liquid Chromatography Coupled with Time-of-Flight Mass Spectrometry

    PubMed Central

    Zhang, Jida; Cai, Hao; Cao, Gang; Liu, Xiao; Wen, Chengping; Fan, Yongsheng

    2013-01-01

    Ultraperformance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF/MS) based on a chemical profiling method was applied to rapidly evaluate the chemical consistency between sun-dried and sulfur-fumigated Radix Paeoniae Alba. By virtue of the high resolution, high speed of UPLC, and the accurate mass measurement of TOFMS coupled with reliable MarkerLynx software, five newly assigned monoterpene glycoside sulfonates were found and identified in sulfur-fumigated Radix Paeoniae Alba samples. This method could be applied for rapid quality evaluation of different kinds of sulfur-fumigated Radix Paeoniae Alba among commercial samples. PMID:24381637

  15. SEPARATION AND PURIFICATION OF TWO MINOR COMPOUNDS FROM RADIX ISATIDIS BY INTEGRATIVE MPLC AND HSCCC WITH PREPARATIVE HPLC

    PubMed Central

    Liang, Zhenjie; Li, Bin; Liang, Yong; Su, Yaping; Ito, Yoichiro

    2014-01-01

    Radix isatidis has been widely used as a Chinese traditional medicine for its anti-virus and anticancer activities where the minor components may contribute to these beneficial pharmaceutical effects. In order to enrich the target minor compounds effectively and rapidly, extraction, medium-pressure liquid chromatography (MPLC), high-speed countercurrent chromatography (HSCCC) and preparative high-performance liquid chromatography (pre-HPLC) were integratively used for separation and purification of two target minor compounds indole-3-acetonitrile-6-O-β-D-glucopyranoside (target 1) and clemastanin B (target 2) in the present study. Radix isatidis was dried, pulverized and extracted with 50% methanol at room temperature, then concentrated and subjected to pretreatment with D-101 macroporous resin chromatography and extraction by MPLC. The first target compound was separated by MPLC at the purity raised to 70–80%, but without the second minor compounds which were irreversibly adsorbed by C18 solid support. Therefore, the second target compound in the crude extract was directly separated by HSCCC at purity of 80–90%. Finally these refined samples were further separated by pre-HPLC to obtain a high purity at 98–99%. The chemical structure identification of each target compound was carried out by IR, ESI-MS and 1H NMR. PMID:25745338

  16. Thermochemical studies on the quantity-antibacterial effect relationship of four organic acids from Radix Isatidis on Escherichia coli growth.

    PubMed

    Kong, Weijun; Zhao, Yanling; Shan, Limei; Xiao, Xiaohe; Guo, Weiying

    2008-07-01

    In this report, we have investigated the inhibitory action of four organic acids from Radix Isatidis on Escherichia coli growth was investigated at 37 degrees C by using a microcalorimeter. The four organic acids were: syringic acid, 2-amino-benzoic acid, salicylic acid, benzoic acid. In accordance with thermokinetic model, the pertaining relationships of the drugs, such as growth inhibitory ratio vs. concentration, maximal power-output vs. growth rate constant, growth rate constant vs. concentration, were obtained. Half-inhibitory concentration of the drugs, IC(50), was obtained by quantitative analysis. From the view of thermodynamics and molecular structure, the relationship between quantity and effect of the four organic acids has been discussed. The functional groups on phenyl ring had important influence on the antibacterial activities. Our work suggests that microcalorimetry is a fast, simple and more sensitive method that can be easily performed and applied to study the anti-bacterial activities of organic acids from Radix Isatidis on microorganism compared to other biological methods. PMID:18591764

  17. Comparison of Volatile Components between Raw and Vinegar Baked Radix Bupleuri by GC-MS Based Metabolic Fingerprinting Approach

    PubMed Central

    Xing, Jie; Sun, Hui-Min; Li, Zhen-Yu; Qin, Xue-Mei

    2015-01-01

    Radix Bupleuri (RB), also named Chaihu in Chinese, is a commonly used herbal drug in traditional Chinese medicine (TCM), and the processing of RB with vinegar to prepare vinegar-baked Radix Bupleuri (VBRB) has a long history in the clinic of TCM. In the present study, GC-MS coupled with multivariate data analysis was applied to compare the volatile components between crude and two vinegar processed RBs. After vinegar baking, the oil yields were decreased significantly, and the chemical compositions were also changed greatly. The chemical changes included the disappearance or appearance, as well as the content increase or decrease of some volatile compounds. The oil yields of two different VBRBs showed no significant difference but differed markedly in their chemical compositions, suggesting that the type of vinegar exerted great impacts on the vinegar-baking process. Thus, the effect of different vinegars on processing should be further investigated to ensure the therapeutic effect and safety of VBRB in clinic. PMID:26265925

  18. Comparing the efficacy of morphologic and DNA-based taxonomy in the freshwater gastropod genus Radix (Basommatophora, Pulmonata)

    PubMed Central

    Pfenninger, Markus; Cordellier, Mathilde; Streit, Bruno

    2006-01-01

    Background Reliable taxonomic identification at the species level is the basis for many biological disciplines. In order to distinguish species, it is necessary that taxonomic characters allow for the separation of individuals into recognisable, homogeneous groups that differ from other such groups in a consistent way. We compared here the suitability and efficacy of traditionally used shell morphology and DNA-based methods to distinguish among species of the freshwater snail genus Radix (Basommatophora, Pulmonata). Results Morphometric analysis showed that shell shape was unsuitable to define homogeneous, recognisable entities, because the variation was continuous. On the other hand, the Molecularly defined Operational Taxonomic Units (MOTU), inferred from mitochondrial COI sequence variation, proved to be congruent with biological species, inferred from geographic distribution patterns, congruence with nuclear markers and crossing experiments. Moreover, it could be shown that the phenotypically plastic shell variation is mostly determined by the environmental conditions experienced. Conclusion Contrary to DNA-taxonomy, shell morphology was not suitable for delimiting and recognising species in Radix. As the situation encountered here seems to be widespread in invertebrates, we propose DNA-taxonomy as a reliable, comparable, and objective means for species identification in biological research. PMID:17123437

  19. Surfactant-Assisted Pressurized Liquid Extraction at Room Temperature for Radix glycyrrhizae by a New Class of Surfactants.

    PubMed

    Heng, Ming Yuan; Thio, Beng Joo Reginald; Ong, Eng Shi

    2016-01-01

    A laboratory-assembled surfactant-assisted pressurized liquid extraction system at room temperature was used for the extraction of glycyrrhizin (GLY) in Radix glycyrrhizae. Environmentally friendly saccharide fatty acid ester such as glucose oleic acid ester is proposed to replace chemical-based surfactants. As the chemical properties of the surfactant obtained were unknown initially, lipase-catalyzed synthesis and liquid chromatography with tandem mass spectrometry were used to ascertain the identity. Surfactant-assisted pressurized liquid extraction (PLE) was carried out dynamically and the extraction efficiencies of the proposed method using different concentration of glucose oleic acid ester were compared with sonication using an organic solvent (ethanol/water, 70:30). The extraction efficiencies of GLY in Radix glycyrrhizae using surfactant-assisted PLE was observed to be higher compared with sonication. The method precision was found to vary from 1.3 to 5.1% (relative standard deviation, RSD, n= 6) on different days. The new method demonstrated the possibility for the extraction to be carried out at room temperature for the production of botanical extracts. PMID:26941412

  20. Binary chromatographic fingerprinting for quality evaluation of Radix Ophiopogonis by high-performance liquid chromatography coupled with ultraviolet and evaporative light-scattering detectors.

    PubMed

    Liu, Li; Lu, Yun; Shao, Qing; Cheng, Yi-Yu; Qu, Hai-Bin

    2007-11-01

    Radix Ophiopogonis is a widely used traditional Chinese medicine. The quality of Radix Ophiopogonis available in the market varies, and some confusing or fake herbs exist. In order to improve the quality control of Radix Ophiopogonis, a novel fingerprinting method was established using HPLC coupled with UV and evaporative light-scattering detectors (ELSDs). Extraction with methanol and liquid-liquid extraction with water-saturated n-butanol were employed for the preparation of the sample solution. Chromatographic separation was performed on a Lichrospher C(18) column (250x4.6 mm id, 5.0 microm particle size) with a linear gradient elution program. UV detection at 280 nm and evaporative light-scattering detection were utilized to obtain two subfingerprinting chromatograms. A novel protocol for data processing was proposed, in order to identify and remove redundant data obtained by the two detectors, and balance the weight of the two subfingerprints on the similarity values. The method was validated and applied to quality evaluation of 16 samples of Radix Ophiopogonis and related herbs. PMID:17874416

  1. Evaluation of the Influence of Sulfur-Fumigated Paeoniae Radix Alba on the Quality of Si Wu Tang by Chromatographic and Chemometric Analysis

    PubMed Central

    Pei, Ke; Duan, Yu; Qiao, Feng-Xian; Tu, Si-Cong; Liu, Xiao; Wang, Xiao-Li; Song, Xiao-Qing; Fan, Kai-Lei; Cai, Bao-Chang

    2016-01-01

    An accurate and reliable method of high-performance liquid chromatographic fingerprint combining with multi-ingredient determination was developed and validated to evaluate the influence of sulfur-fumigated Paeoniae Radix Alba on the quality and chemical constituents of Si Wu Tang. Multivariate data analysis including hierarchical cluster analysis and principal component analysis, which integrated with high-performance liquid chromatographic fingerprint and multi-ingredient determination, was employed to evaluate Si Wu Tang in a more objective and scientific way. Interestingly, in this paper, a total of 37 and 36 peaks were marked as common peaks in ten batches of Si Wu Tang containing sun-dried Paeoniae Radix Alba and ten batches of Si Wu Tang containing sulfur-fumigated Paeoniae Radix Alba, respectively, which indicated the changed fingerprint profile of Si Wu Tang when containing sulfur-fumigated herb. Furthermore, the results of simultaneous determination for multiple ingredients showed that the contents of albiflorin and paeoniflorin decreased significantly (P < 0.01) and the contents of gallic acid and Z-ligustilide decreased to some extent at the same time when Si Wu Tang contained sulfur-fumigated Paeoniae Radix Alba. Therefore, sulfur-fumigation processing may have great influence on the quality of Chinese herbal prescription. PMID:27034892

  2. The Inhibition of Mast Cell Activation of Radix Paeoniae alba Extraction Identified by TCRP Based and Conventional Cell Function Assay Systems

    PubMed Central

    Fu, Huiying; Cheng, Hongqiang; Cao, Gang; Zhang, Xingde; Tu, Jue; Sun, Mingjiao; Mou, Xiaozhou; Shou, Qiyang; Ke, Yuehai

    2016-01-01

    Chinese herbs have long been used to treat allergic disease, but recently the development was greatly impeded by the lack of good methods to explore the mechanism of action. Here, we showed the effects of Chinese herb Radix Paeoniae alba were identified and characterized by a mast cell activation assay that involves electronic impedance readouts for dynamic monitoring of cellular responses to produce time-dependent cell responding profiles (TCRPs), and the anti-allergic activities were further confirmed with various conventional molecular and cell biology tools. We found Radix P. alba can dose-dependently inhibit TCPRs, and have anti-allergic function in vitro and in vivo. Radix P. alba suppressed mast cell degranulation not only inhibiting the translocation of granules to the plasma membrane, but also blocking membrane fusion and exocytosis; and that there may be other anti-allergic components in addition to paeoniflorin. Our results suggest that Radix P. alba regulated mast cell activation with multiple targets, and this approach is also suitable for discovering other mast cell degranulation-targeting Chinese herbs and their potential multi-target mechanisms. PMID:27195739

  3. Analysis of baicalein, baicalin and wogonin in Scutellariae radix and its preparation by microemulsion electrokinetic chromatography with 1-butyl-3-methylimizolium tetrafluoborate ionic liquid as additive.

    PubMed

    Zhang, Huige; Tian, Kan; Tang, Jianghong; Qi, Shengda; Chen, Hongli; Chen, Xingguo; Hu, Zhide

    2006-10-01

    Microemulsion electrokinetic chromatography (MEEKC) using 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM-BF4) ionic liquid (IL) as additive was developed for the analysis of baicalin, wogonin and baicalein in Scutellariae radix and its preparation. After conducting a series of optimizations, baseline separation was obtained for the analytes within 5min under the optimum conditions (sodium dodecyl sulfate (SDS) 0.88% (m/v) ethyl acetate 0.8% (v/v) butan-1-ol 0.2% (v/v) and the buffer composition were 25% acetonitrile (v/v), 7.5 mM BMIM-BF4 and 10 mM NaH2PO4, pH 8.2, applied voltage 17.5 kV and detection at 254 nm), the method has been successfully applied to the determination and quantification of the analytes in the extracts of S. radix (cooked), S. radix (raw) and Qingfeiyihuowan which was the preparation including S. radix. PMID:16952364

  4. Sub-seasonal oxygen and carbon isotope variations in shells of modern Radix sp. (Gastropoda) from the Tibetan Plateau: potential of a new archive for palaeoclimatic studies

    NASA Astrophysics Data System (ADS)

    Taft, Linda; Wiechert, Uwe; Riedel, Frank; Weynell, Marc; Zhang, Hucai

    2012-02-01

    Carbon and oxygen isotope ratios have been measured for nine aragonite shells of the gastropod genus Radix from the lake Bangda Co (30°29'N, 97°04'E, 4450 m a.s.l.) at the south-eastern edge and from two characteristic sites at the lake Kyaring Co (31°09'N, 88°17'E, 4650 m a.s.l.) on the central Tibetan Plateau. Radix shells were sampled for isotope ratio analysis with high spatial resolution along the ontogenetic spiral of growth providing the basis of isotope records with a sub-seasonal time-resolution. δ18O values of shells from Bangda Co are on average ˜-15.0‰ relative to PDB and the pattern exhibits a clear onset and progression of the summer monsoon precipitation indicated by a strong "amount effect". This pattern mirrors the precipitation pattern in the respective year and region as expected for a small (surface area ca 0.3 km2) and shallow (<5 m) lake or habitat with short water residence times and little evaporative 18O enrichment of the lake water. In contrast, δ18O values of Radix shells from Kyaring Co habitat A which is connected to the deep (several tens of metres) and big (surface area ca 660 km2) lake, average at ˜-13.0‰ consistent with a higher evaporation rate and longer water residence time. The latter is supported by more 18O enriched water in this habitat. The δ18O values of Radix shells from Kyaring Co habitat B are nearly as low as shells from Bangda Co due to the similar habitat characteristic but isotopic patterns of these shells exhibit a weaker "amount effect". In both lake systems δ13C values of the shells are coupled with oxygen isotopes because a large amount of isotopically light carbon is washed from mountain slopes into the lake during the rainy season. Although other processes influence the isotopic patterns, e.g. biological productivity (δ13C) or temperature (δ18O), these influences are minor compared with the monsoon signal or the effect of evaporation in the Radix shell records. The overall weaker amount effect

  5. Novel composition of polymer gel dosimeters based on N-(Hydroxymethyl)acrylamide for radiation therapy

    NASA Astrophysics Data System (ADS)

    Basfar, Ahmed A.; Moftah, Belal; Rabaeh, Khalid A.; Almousa, Akram A.

    2015-07-01

    A new composition of polymer gel dosimeters is developed based on radiation induced polymerization of N-(Hydroxymethyl)acrylamide (NHMA) for radiotherapy treatment planning. The dosimeters were irradiated by 10 MV photon beam of a medical linear accelerator at a constant dose rate of 600 cGy/min with doses up to 20 Gy. The polymerization occurs and increases with increasing absorbed dose. The dose response of polymer gel dosimeters was studied using nuclear magnetic imaging (NMR) for relaxation rate (R2) of water proton. Dose rate, energy of radiation and the stability of the polymerization after irradiation were investigated. No appreciable effects of these parameters on the performance of the novel gel dosimeters were observed.

  6. Measurements of entrance surface dose using a fiber-optic dosimeter in diagnostic radiology

    NASA Astrophysics Data System (ADS)

    Yoo, Wook Jae; Seo, Jeong Ki; Shin, Sang Hun; Han, Ki-Tek; Jeon, Dayeong; Jang, Kyoung Won; Sim, Hyeok In; Lee, Bongsoo; Park, Jang-Yeon

    2013-03-01

    In this study, a fiber-optic dosimeter (FOD) was developed to measure entrance surface dose (ESD) in diagnostic radiology. We measured the scintillating lights in order to obtain ESDs, which changed with the various exposure parameters of a digital radiography (DR) system, such as tube potential, current-time product, focus-surface distance (FSD), and field size, using the fabricated FOD system. From the experimental results, the output light signals of the FOD were similar to the ESDs of the conventional semiconductor dosimeter. In conclusion, we characterized the measured ESDs as functions of exposure parameters by using two different types of dosimeters and demonstrated that the proposed FOD using a plastic scintillating fiber and a plastic optical fiber (POF) makes it possible to measure ESDs in the energy range of diagnostic radiology. From the results of this study, it is anticipated that the FOD will be a useful dosimeter in low-energy photon applications including diagnostic radiology.

  7. NASA Crew Personal Active Dosimeters (CPADs): Leveraging Novel Terrestrial Personal Radiation Monitoring Capabilities for Space Exploration

    NASA Technical Reports Server (NTRS)

    Leitgab, Martin; Semones, Edward; Lee, Kerry

    2016-01-01

    The NASA Space Radiation Analysis Group (SRAG) is developing novel Crew Personal Active Dosimeters (CAPDs) for upcoming crewed space exploration missions and beyond. To reduce the resource footprint of the project a COTS dosimeter base is used for the development of CPADs. This base was identified from evaluations of existing COTS personal dosimeters against the concept of operations of future crewed missions and tests against detection requirements for radiation characteristic of the space environment. CPADs exploit operations efficiencies from novel features for space flight personal dosimeters such as real-time dose feedback, and autonomous measuring and data transmission capabilities. Preliminary CPAD design, results of radiation testing and aspects of operational integration will be presented.

  8. Performance of KCl:Eu2+ storage phosphor dosimeters for low dose measurements

    PubMed Central

    Li, H. Harold; Hansel, Rachael; Knutson, Nels; Yang, Deshan

    2013-01-01

    Recent research has demonstrated that europium doped potassium chloride (KCl:Eu2+) storage phosphor material has the potential to become the physical foundation of a novel and reusable dosimetry system using either film-like devices or devices similar to thermoluminescent dosimeter (TLD) chips. The purposes of this work are to quantify the performance of KCl:Eu2+ prototype dosimeters for low dose measurements and to demonstrate how it can be incorporated into clinical application for in vivo peripheral dose measurements. Pellet-style KCl:Eu2+ dosimeters, 6 mm in diameter, and 1 mm thick, were fabricated in-house for this study. The dosimeters were read using a laboratory photostimulated luminescence detection system. KCl:Eu2+ prototype storage phosphor dosimeter was capable of measuring a dose-to-water as low as 0.01 cGy from a 6 MV photon beam with a signal-to-noise ratio greater than 6. A pre-readout thermal annealing procedure enabled the dosimeter to be read within an hour post irradiation. After receiving large accumulated doses (~10 kGy), the dosimeters retained linear response in the low dose region with only a 20 percent loss of sensitivity comparing to a fresh sample (zero Gy history). The energy-dependence encountered during low dose peripheral measurements could be accounted for via a single point outside-field calibration per each beam quality. With further development the KCl:Eu2+− based dosimeter could become a versatile and durable dosimetry tool with large dynamic range (sub-cGy to 100 Gy). PMID:23735856

  9. Impact of the Fukushima nuclear accident on background radiation doses measured by control dosimeters in Japan.

    PubMed

    Romanyukha, Alexander; King, David L; Kennemur, Lisa K

    2012-05-01

    After the 9.0 magnitude earthquake and subsequent massive tsunami on 11 March 2011 in Japan, several reactors at the Fukushima Daiichi Nuclear Power Plant suffered severe damage. There was immediate participation of U.S. Navy vessels and other United States Department of Defense (DoD) teams that were already in the area at the time of the disaster or arrived shortly thereafter. The correct determination of occupational dose equivalent requires estimation of the background dose component measured by control dosimeters, which is subsequently subtracted from the total dose equivalent measured by personal dosimeters. The purpose of the control dosimeters is to determine the amount of radiation dose equivalent that has accumulated on the dosimeter from background or other non-occupational sources while they are in transit or being stored. Given the release of radioactive material and potential exposure to radiation from the Fukushima Daiichi Nuclear Power Plant and the process by which the U.S. Navy calculates occupational exposure to ionizing radiation, analysis of pre- and post-event control dosimeters is warranted. Several hundred historical dose records from the Naval Dosimetry Center (NDC) database were analyzed and compared with the post-accident dose equivalent data of control dosimeters. As result, it was shown that the dose contribution of the radiation and released radiological materials from the Fukushima nuclear accident to background radiation doses is less than 0.375 μSv d for shallow and deep photon dose equivalent. There is no measurable effect on neutron background exposure. The latter has at least two important conclusions. First, the NDC can use doses measured by control dosimeters at issuing sites in Japan for determination of personnel dose equivalents; second, the dose data from control dosimeters prior to and after the Fukushima accident may be used to assist in dose reconstruction of non-radiological (non-badged) personnel at these locations

  10. Dose control in electron beam processing: Comparison of results from a graphite charge collector, routine dosimeters and the ISS alanine-based dosimeter

    NASA Astrophysics Data System (ADS)

    Fuochi, P. G.; Onori, S.; Casali, F.; Chirco, P.

    1993-10-01

    A 12 MeV linear accelerator is currently used for electron beam processing of power semiconductor devices for lifetime control and, on an experimental basis, for food irradiation, sludge treatment etc. In order to control the irradiation process a simple, quick and reliable method for a direct evaluation of dose and fluence in a broad electron beam has been developed. This paper presents the results obtained using a "charge collector" which measures the charge absorbed in a graphite target exposed in air. Calibration of the system with super-Fricke dosimeter and comparison of absorbed dose results obtained with plastic dosimeters and alanine pellets are discussed.

  11. Small-Field Measurements of 3D Polymer Gel Dosimeters through Optical Computed Tomography

    PubMed Central

    Shih, Cheng-Ting; Lee, Yao-Ting; Wu, Shin-Hua; Yao, Chun-Hsu; Hsieh, Bor-Tsung

    2016-01-01

    With advances in therapeutic instruments and techniques, three-dimensional dose delivery has been widely used in radiotherapy. The verification of dose distribution in a small field becomes critical because of the obvious dose gradient within the field. The study investigates the dose distributions of various field sizes by using NIPAM polymer gel dosimeter. The dosimeter consists of 5% gelatin, 5% monomers, 3% cross linkers, and 5 mM THPC. After irradiation, a 24 to 96 hour delay was applied, and the gel dosimeters were read by a cone beam optical computed tomography (optical CT) scanner. The dose distributions measured by the NIPAM gel dosimeter were compared to the outputs of the treatment planning system using gamma evaluation. For the criteria of 3%/3 mm, the pass rates for 5 × 5, 3 × 3, 2 × 2, 1 × 1, and 0.5 × 0.5 cm2 were as high as 91.7%, 90.7%, 88.2%, 74.8%, and 37.3%, respectively. For the criteria of 5%/5 mm, the gamma pass rates of the 5 × 5, 3 × 3, and 2 × 2 cm2 fields were over 99%. The NIPAM gel dosimeter provides high chemical stability. With cone-beam optical CT readouts, the NIPAM polymer gel dosimeter has potential for clinical dose verification of small-field irradiation. PMID:26974434

  12. The thermoluminescence study of epoxy based LiF:Mg,Cu,P dosimeters

    NASA Astrophysics Data System (ADS)

    Rahangdale, S. R.; Wankhede, S. P.; Kadam, Sonal; Dhabekar, Bhushan. S.; Palikundwar, U. A.; Moharil, S. V.

    2016-05-01

    The LiF:Mg,Cu,P phosphor is the most investigated phosphor in radiation dosimetry. Results on thermoluminescence of the epoxy based LiF:Mg,Cu,P dosimeters irradiated with gamma radiations are presented and compared with results of LiF:Mg,Cu,P powder. The glow curve structure of both LiF powder and dosimeter are same and only difference is found in the glow curve peak temperature. The LiF dosimeters were made from the 5012A and 5012B epoxy. The dosimeters had a mass of about 18 mg, 5.0 mm diameter and 0.5 mm thickness. The sensitivity variation of the dosimeters for exposure to 60Co gamma rays at different angles of incidence of the radiation is found to be within 4%. Its minimum detectable dose is about 3020 µGy. The epoxy based dosimeters withstand different environment and it can be used with general TL reader without need of any special design due to its small size and plane surface.

  13. Characterization of a water-equivalent fiber-optic coupled dosimeter for use in diagnostic radiology

    SciTech Connect

    Hyer, Daniel E.; Fisher, Ryan F.; Hintenlang, David E.

    2009-05-15

    This work reports on the characterization of a new fiber-optic coupled (FOC) dosimeter for use in the diagnostic radiology energy range. The FOC dosimeter was constructed by coupling a small cylindrical plastic scintillator, 500 {mu}m in diameter and 2 mm in length, to a 2 m long optical fiber, which acts as a light guide to transmit scintillation photons from the sensitive element to a photomultiplier tube (PMT). A serial port interface on the PMT permits real-time monitoring of light output from the dosimeter via a custom computer program. The FOC dosimeter offered excellent sensitivity and reproducibility, allowing doses as low as 0.16 mGy to be measured with a coefficient of variation of only 3.64%. Dose linearity was also excellent with a correlation coefficient of 1.000 over exposures ranging from 0.16 to 57.29 mGy. The FOC dosimeter exhibited little angular dependence from axial irradiation, varying by less than 5% over an entire revolution. A positive energy dependence was observed and measurements performed within a scatter medium yielded a 10% variation in sensitivity as beam quality changed due to hardening and scatter across a 16 cm depth range. The current dosimetry system features an array of five PMTs to allow multiple FOC dosimeters to be monitored simultaneously. Overall, the system allows for rapid and accurate dose measurements relevant to a range of diagnostic imaging applications.

  14. Preparation of polymer gel dosimeters based on less toxic monomers and gellan gum

    NASA Astrophysics Data System (ADS)

    Hiroki, A.; Sato, Y.; Nagasawa, N.; Ohta, A.; Seito, H.; Yamabayashi, H.; Yamamoto, T.; Taguchi, M.; Tamada, M.; Kojima, T.

    2013-10-01

    New polymer gel dosimeters consisting of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol monoethyl ether monomethacrylate (TGMEMA), polyethylene glycol 400 dimethacrylate (9G), tetrakis (hydroxymethyl) phosphonium chloride as an antioxidant, and gellan gum as a gel matrix were prepared. They were optically analyzed by measuring absorbance to evaluate a dose response. The absorbance of the polymer gel dosimeters that were exposed to 60Co γ-rays increased with increasing dose. The dosimeters comprising HEMA and 9G showed a linear increase in absorbance in the dose range from 0 to 10 Gy. The dose response depended on the 9G concentration. For others comprising HEMA, 9G and TGMEMA, the absorbance of the polymer gel dosimeters drastically increased above a certain dose, and then leveled off up to 10 Gy. The optical variations in these polymer gel dosimeters were also induced by x-irradiation from Cyberknife radiotherapy equipment. Furthermore, the exposed region of the latter polymer gel dosimeter exhibited a thermo-responsive behavior.

  15. An investigation into the sensitivity of various albedo neutron dosimeters aimed at correcting the readings

    NASA Astrophysics Data System (ADS)

    Alekseev, A. G.; Mokrov, Yu. V.; Morozova, S. V.

    2012-03-01

    The results of an experimental determination of the sensitivity of three types of individual neutron albedo dosimeters in neutron reference fields on the basis of radionuclide sources and at the top concrete shielding of the U-70 accelerator are presented. The results show that the ratios between the responses of the albedo dosimeters designed earlier at the Joint Institute for Nuclear Research (the albedo dosimeter (AD) and the multicomponent dosimeter (MD)) and the currently used DVGN-01 dosimeter are constant within 25% in a wide range of neutron energy. This fact makes it possible to use the results of measuring the AD and MD responses obtained earlier in neutron fields of nuclear-physical installations at the Joint Institute for Nuclear Research (JINR) for the correction of DVGN-01 dosimeter measurement results to apply it to personal radiation monitoring (PRM) at these installations. The correction factors for DVGN-01 measurement results are found and recommended to be used in PRM for most JINR installations.

  16. Characterization of a Tissue-Equivalent Dosimeter based on CMOS Solid-State Photomultipliers

    NASA Astrophysics Data System (ADS)

    Johnson, Erik; Benton, Eric; Stapels, Christopher; Chrsitian, James; Jie Chen, Xiao

    Available digital dosimeters are bulky and unable to provide real-time monitoring of dose from space radiation. The complexity of space-flight design requires reliable, fault-tolerant equip-ment capable of providing real-time dosimetry during a mission, which is not feasible with the existing thermoluminescent dosimeter (TLD) technology, especially during extravehicular activity (EVA). Real-time monitoring is important for low-Earth orbiting spacecraft and inter-planetary space flight to alert the crew when Solar Particle Events (SPE) increase the particle flux of the spacecraft environment. A dosimeter-on-a-chip for personal dosimetry is comprised of a tissue-equivalent scintillator coupled to a solid-state photomultiplier (SSPM) built using CMOS technology. The radiation sensitive component of the dosimeter is coupled to analog signal processing components and a microprocessor, which can maintain processing fidelity up to 5x105 events per second. The dynamic range of the dosimeter has been verified from 1-GeV protons (0.22 keV/µm in H20) to 420 MeV/n Fe (201.1 keV/µm in H20). The dosimeter confirmed doses to within 3

  17. N-isopropylacrylamide gel dosimeter to evaluate clinical photon beam characteristics.

    PubMed

    Chiu, Chung-Yu; Tsang, Yuk-Wah; Hsieh, Bor-Tsung

    2014-08-01

    The introduction of beam intensity control concept in current radiotherapy techniques has increased treatment planning complexity. Thus, small-field dose measurement has become increasingly vital. Polymer gel dosimetry method is widely studied. It is the only dose measurement tool that provides 3D dose distribution. This study aims to use an N-isopropylacrylamide (NIPAM) gel dosimeter to conduct beam performance measurements of percentage depth dose (PDD), beam flatness, and symmetry for photon beams with field sizes of 3×3 and 4×4 cm(2). Computed tomography scans were used to readout the gel dosimeters. In the PDD measurement, the NIPAM gel dosimeter and Gafchromic™ EBT3 radiochromic film displayed high consistency in the region deeper than the build-up region. The gel dosimeter dose profile had 3% lower flatness and symmetry measurement at 5 cm depth for different fields compared with that of the Gafchromic™ EBT3 film. During gamma evaluation under 3%/3 mm dose difference/distance-to-agreement standard, the pass rates of the polymer gel dosimeter to the TPS and EBT3 film were both higher than 96%. Given that the gel is tissue equivalent, it did not exhibit the energy dependence problems of radiochromic films. Therefore, the practical use of NIPAM polymer gel dosimeters is enhanced in clinical dose verification. PMID:24836904

  18. Antioxidant activities of saponins extracted from Radix Trichosanthis: an in vivo and in vitro evaluation

    PubMed Central

    2014-01-01

    Background Radix Trichosanthis (RT), the dry root tuber of Trichosanthis kirilowii Maxim (Cucurbitaceae), is a traditional Chinese medicine. Although a wide range of saponin pharmacological properties has been identified, to our knowledge, this may be the first report to investigate the crude saponins from RT. The purpose of this study was to delineate the antioxidant activity both in vitro and in vivo by using ethyl acetate (EtOAc), n-butanol, and the mixture of n-butanol and EtOAc fractions. Methods In vitro antioxidant activity was detected by using DPPH free radical, hydrogen peroxide scavenging, and reducing power assays. After pretreatment with different fractions saponins at 2 mg/kg/d and 3 mg/kg/d of crude drug, respectively, an established CCl4 induced acute cytotoxicity model was used to evaluate the in vivo antioxidant potential by detection of superoxide dismutase (SOD), malonaldehyde (MDA), lactate dehydrogenase (LDH), and total antioxidant capacity (T-AOC) levels. Results The in vitro assay showed that the antioxidant activity of all the three fractions was promising. The reducing power of the EtOAc and the mixture of n-butanol and EtOAc extracts increased in a dose dependent manner. However, both the n-butanol and the mixture of n-butanol and EtOAc fractions in low dose exhibited in a time dependent manner with prolonged reaction time. As for hydrogen peroxide scavenging capability, the n-butanol fraction mainly demonstrated a time dependent manner, whereas EtOAc fraction showed a dose dependent manner. However, in case of in vivo assay, an increase of SOD and T-AOC and decrease of MDA and LDH levels were only observed in n-butanol (2 mg/kg/d of crude drug) extracts pretreatment group. Conclusions RT saponins in n-butanol fraction might be a potential antioxidant candidate, as CCl4-induced oxidative stress has been found to be alleviated, which may be associated with the time dependent manner of n-butanol saponins in a low dose. Further studies

  19. Therapeutic effects of radix dipsaci, pyrola herb, and cynomorium songaricum on bone metabolism of ovariectomized rats

    PubMed Central

    2012-01-01

    Background The objective of this study was to evaluate the effects of herbal medicines, such as Radix Dipsaci (RDD), Pyrola Herb (PHD), and Cynomorium songaricum decoction (CSD), on osteoporotic rats induced by ovariectomy (OVX). Methods OVX or sham operations were performed on 69 virgin Wistar rats that were divided into six groups: sham (sham, n = 12), OVX control group (OVX, n = 12), and OVX rats with treatments (diethylstilbestrol, E2, n = 12; RDD, n = 11, PHD, n = 11, and CSD, n = 11). Non-surgical rats served as normal control (NC, n = 12). The treatments began four weeks after surgery and lasted for 12 weeks. Bone mass and bone turnover were analyzed by histomorphometry. Levels of protein expression and mRNA of OPG and RANKL in osteoblasts (OB) and bone marrow stromal cells (bMSC) were evaluated by immunohistochemistry and in situ hybridization. Results Compared to NC and sham rats, trabecular bone formation was significantly reduced in OVX rats, but restored in E2-treated rats. Treatment with either RDD or PHD enhanced trabecular bone formation remarkably. No significant change of bone formation was observed in CSD-treated rats. OPG expression of protein and mRNA was reduced significantly in OB and bMSC of OVX control rats. RANKL expression of protein and mRNA was increased significantly in OB and bMSC of OVX control rats. These effects were substantially reversed (increased in OPG and decreased in RANKL) by treatment with E2, RDD, or PHD in OB and bMSC of OVX rats. No significant changes in either OPG or RANKL expression were observed in OB and bMSC of OVX rats treated with CSD. Conclusions Our study showed that RDD and PHD increased bone formation by stimulating overexpression of OPG and downregulation of RANKL in OB and bMSC. This suggests that RDD and PHD may be used as alternative therapeutic agents for postmenopausal osteoporosis. PMID:22639966

  20. Effect of charred Radix et Rhizoma Rhei in a laser-induced choroidal neovascularization murine model.

    PubMed

    Han, Dongmei; Yao, Yuan; Sun, Yong; Gong, Yuanyuan; Wu, Xingwei

    2015-04-01

    A pharmaceutical composition (patent no. WO2012079419) exhibited favorable outcomes in a clinical trial of wet age‑related macular degeneration. The aims of the present study were to explore the effects of one composition component, charred Radix et Rhizoma Rhei (CRRR), in a laser‑induced choroidal neovascularization (CNV) murine model. A total of 30 eight‑week‑old C57BL/6 mice were subjected to diode laser treatment, and CNV was induced by rupturing the Bruch's membrane. The mice were then randomly divided into two groups: the CRRR‑treated group that was administered CRRR water extract (concentration, 0.6 g/100 ml; dose, 1 ml/0.1 kg twice a day for 21 days); and the control group that was treated with saline (dose, 1 ml/0.1 kg twice a day for 21 days). The retinal tissue was subjected to quantitative polymerase chain reaction (qPCR) and western blot analysis to determine the expression levels of interleukin‑10 (IL‑10) and vascular epithelial growth factor (VEGF) at day seven following laser treatment. At weeks 2 and 3 after laser treatment, fundus fluorescein angiography was performed and graded to assess the severity of lesion leakage. Retinal flat mounts were prepared for three‑dimensional confocal microscopy at day 22 after laser treatment. At days 14 and 21 after laser treatment, no statistically significant differences were observed between the clinically relevant lesions of the CRRR‑treated and control mice. CNV volumes were not found to be significantly different between the CRRR‑treated and control mice. The expression levels of IL‑10 were significantly increased in the CRRR‑treated mice (P<0.05). However, no statistically significant differences were observed between the VEGF expression levels of the CRRR‑treated and control mice. In conclusion, CRRR did not appear to significantly inhibit CNV in this murine model. The function of CRRR in the pharmaceutical composition may be due to the effects of IL‑10 and a synergistic effect

  1. Cardiovascular actions of Radix Stephaniae Tetrandrae: a comparison with its main component, tetrandrine.

    PubMed

    Wong, T M; Wu, S; Yu, X C; Li, H Y

    2000-12-01

    A comparison of the cardiovascular actions of the extract of Radix Stephaniae Tetrandrae (RST), the root of a Chinese hero Stephania tetrandra S Moore, in rats with those of tetrandrine (Tet), the best known active component of RST was reviewed. The RST extract inhibits Ca2+ influx into the myocyte and reduces protein release during reperfusion with a Ca2+ containing solution following perfusion with a Ca2+ free solution (Ca2+ paradox), and arrhythmia during reperfusion in the isolated perfused heart. It also reduces the infarct size induced by ischemia/reperfusion in vitro and in vivo. In addition, the RST extract suppresses elevation of arterial blood pressure in DOCA-salt hypertensive rats. It does not further reduce the heart rate and coronary flow significantly during myocardial ischemia. The effects are similar to those of Tet. When compared with the same doses of Tet alone, the RST extract, of which 9% is Tet, produces equally potent effects on infarction, arrhythmias, coronary flow and heart rate, and has a greater inhibitory effect on protein release during Ca2+ paradox. The combination at 1:1 ratio of Tet and fangchinoline (Fan), another main component, which constitutes 6% of the RST extract and has no significant effects on the heart, produces comparable effects on protein release during Ca2+ paradox as Tet alone. The observations suggest that the efficacy of the RST extract cannot be accounted for by Tet alone. Some of the effects may be due to an interaction between the components of the extract. The RST extract also produces similar effects as verapamil, a prototype Ca2+ channel antagonist widely used in the treatment of ischemic heart diseases and hypertension, except that verapamil, at 1 mumol/L, a concentration that produces similar cardiac effects as the RST extract, further reduces heart rate significantly during ischemia. So the RST extract may be a therapeutically better agent in the treatment of ischemic heart diseases and hypertension than

  2. Validation of an "Intelligent Mouthguard" Single Event Head Impact Dosimeter.

    PubMed

    Bartsch, Adam; Samorezov, Sergey; Benzel, Edward; Miele, Vincent; Brett, Daniel

    2014-11-01

    Dating to Colonel John Paul Stapp MD in 1975, scientists have desired to measure live human head impacts with accuracy and precision. But no instrument exists to accurately and precisely quantify single head impact events. Our goal is to develop a practical single event head impact dosimeter known as "Intelligent Mouthguard" and quantify its performance on the benchtop, in vitro and in vivo. In the Intelligent Mouthguard hardware, limited gyroscope bandwidth requires an algorithm-based correction as a function of impact duration. After we apply gyroscope correction algorithm, Intelligent Mouthguard results at time of CG linear acceleration peak correlate to the Reference Hybrid III within our tested range of pulse durations and impact acceleration profiles in American football and Boxing in vitro tests: American football, IMG=1.00REF-1.1g, R2=0.99; maximum time of peak XYZ component imprecision 3.6g and 370 rad/s2; maximum time of peak azimuth and elevation imprecision 4.8° and 2.9°; maximum average XYZ component temporal imprecision 3.3g and 390 rad/s2. Boxing, IMG=1.00REF-0.9 g, R2=0.99, R2=0.98; maximum time of peak XYZ component imprecision 3.9 g and 390 rad/s2, maximum time of peak azimuth and elevation imprecision 2.9° and 2.1°; average XYZ component temporal imprecision 4.0 g and 440 rad/s2. In vivo Intelligent Mouthguard true positive head impacts from American football players and amateur boxers have temporal characteristics (first harmonic frequency from 35 Hz to 79 Hz) within our tested benchtop (first harmonic frequency<180 Hz) and in vitro (first harmonic frequency<100 Hz) ranges. Our conclusions apply only to situations where the rigid body assumption is valid, sensor-skull coupling is maintained and the ranges of tested parameters and harmonics fall within the boundaries of harmonics validated in vitro. For these situations, Intelligent Mouthguard qualifies as a single event dosimeter in American football and Boxing. PMID:26192948

  3. An investigation of a PRESAGE® in vivo dosimeter for brachytherapy

    NASA Astrophysics Data System (ADS)

    Vidovic, A. K.; Juang, T.; Meltsner, S.; Adamovics, J.; Chino, J.; Steffey, B.; Craciunescu, O.; Oldham, M.

    2014-07-01

    Determining accurate in vivo dosimetry in brachytherapy treatment with high dose gradients is challenging. Here we introduce, investigate, and characterize a novel in vivo dosimeter and readout technique with the potential to address this problem. A cylindrical (4 mm × 20 mm) tissue equivalent radiochromic dosimeter PRESAGE® in vivo (PRESAGE®-IV) is investigated. Two readout methods of the radiation induced change in optical density (OD) were investigated: (i) volume-averaged readout by spectrophotometer, and (ii) a line profile readout by 2D projection imaging utilizing a high-resolution (50 micron) telecentric optical system. Method (i) is considered the gold standard when applied to PRESAGE® in optical cuvettes. The feasibility of both methods was evaluated by comparison to standard measurements on PRESAGE® in optical cuvettes via spectrophotometer. An end-to-end feasibility study was performed by a side-by-side comparison with TLDs in an 192Ir HDR delivery. 7 and 8 Gy was delivered to PRESAGE®-IV and TLDs attached to the surface of a vaginal cylinder. Known geometry enabled direct comparison of measured dose with a commissioned treatment planning system. A high-resolution readout study under a steep dose gradient region showed 98.9% (5%/1 mm) agreement between PRESAGE®-IV and Gafchromic® EBT2 Film. Spectrometer measurements exhibited a linear dose response between 0-15 Gy with sensitivity of 0.0133 ± 0.0007 ΔOD/(Gy ṡ cm) at the 95% confidence interval. Method (ii) yielded a linear response with sensitivity of 0.0132 ± 0.0006 (ΔOD/Gy), within 2% of method (i). Method (i) has poor spatial resolution due to volume averaging. Method (ii) has higher resolution (˜1 mm) without loss of sensitivity or increased noise. Both readout methods are shown to be feasible. The end-to-end comparison revealed a 2.5% agreement between PRESAGE®-IV and treatment plan in regions of uniform high dose. PRESAGE®-IV shows promise for in vivo dose verification

  4. Analysis of the influence of sulfur-fumigation on the volatile components of Angelicae sinensis Radix by comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry

    PubMed Central

    Cao, Gang; Cai, Hao; Lou, Yajing; Tu, Sicong; Liu, Xiao; Qin, Kunming; Cai, Baochang

    2014-01-01

    Background: Sulfur-fumigation of Angelicae sinensis Radix causes changes in the structure and composition of volatile components. These changes alter the curative effect and the quality of A. sinensis Radix. Materials and Methods: In this study, comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS) was employed to investigate the influence of sulfur-fumigation on the volatile components, and to characterize and quantify the chemical composition of the volatile oil of A. sinensis Radix. Results: The present study has shown that sulfur-fumigated A. sinensis Radix samples had significant loss of the main active compounds and a more destructive fingerprint profile compared to non-fumigated samples. Conclusion: From this study, it can be concluded that the combination of GC × GC and TOFMS has potential as a quality monitoring tool in herbal medicine and food processing industries. PMID:25210318

  5. Development of a wavelength-separated type scintillator with optical fiber (SOF) dosimeter to compensate for the Cerenkov radiation effect

    PubMed Central

    Ishikawa, Masayori; Nagase, Naomi; Matsuura, Taeko; Hiratsuka, Junichi; Suzuki, Ryusuke; Miyamoto, Naoki; Sutherland, Kenneth Lee; Fujita, Katsuhisa; Shirato, Hiroki

    2015-01-01

    The scintillator with optical fiber (SOF) dosimeter consists of a miniature scintillator mounted on the tip of an optical fiber. The scintillator of the current SOF dosimeter is a 1-mm diameter hemisphere. For a scintillation dosimeter coupled with an optical fiber, measurement accuracy is influenced by signals due to Cerenkov radiation in the optical fiber. We have implemented a spectral filtering technique for compensating for the Cerenkov radiation effect specifically for our plastic scintillator-based dosimeter, using a wavelength-separated counting method. A dichroic mirror was used for separating input light signals. Individual signal counting was performed for high- and low-wavelength light signals. To confirm the accuracy, measurements with various amounts of Cerenkov radiation were performed by changing the incident direction while keeping the Ir-192 source-to-dosimeter distance constant, resulting in a fluctuation of <5%. Optical fiber bending was also addressed; no bending effect was observed for our wavelength-separated SOF dosimeter. PMID:25618136

  6. Development of a wavelength-separated type scintillator with optical fiber (SOF) dosimeter to compensate for the Cerenkov radiation effect.

    PubMed

    Ishikawa, Masayori; Nagase, Naomi; Matsuura, Taeko; Hiratsuka, Junichi; Suzuki, Ryusuke; Miyamoto, Naoki; Sutherland, Kenneth Lee; Fujita, Katsuhisa; Shirato, Hiroki

    2015-03-01

    The scintillator with optical fiber (SOF) dosimeter consists of a miniature scintillator mounted on the tip of an optical fiber. The scintillator of the current SOF dosimeter is a 1-mm diameter hemisphere. For a scintillation dosimeter coupled with an optical fiber, measurement accuracy is influenced by signals due to Cerenkov radiation in the optical fiber. We have implemented a spectral filtering technique for compensating for the Cerenkov radiation effect specifically for our plastic scintillator-based dosimeter, using a wavelength-separated counting method. A dichroic mirror was used for separating input light signals. Individual signal counting was performed for high- and low-wavelength light signals. To confirm the accuracy, measurements with various amounts of Cerenkov radiation were performed by changing the incident direction while keeping the Ir-192 source-to-dosimeter distance constant, resulting in a fluctuation of <5%. Optical fiber bending was also addressed; no bending effect was observed for our wavelength-separated SOF dosimeter. PMID:25618136

  7. Investigations of interference between electromagnetic transponders and wireless MOSFET dosimeters: A phantom study

    PubMed Central

    Su, Zhong; Zhang, Lisha; Ramakrishnan, V.; Hagan, Michael; Anscher, Mitchell

    2011-01-01

    Purpose: To evaluate both the Calypso Systems’ (Calypso Medical Technologies, Inc., Seattle, WA) localization accuracy in the presence of wireless metal–oxide–semiconductor field-effect transistor (MOSFET) dosimeters of dose verification system (DVS, Sicel Technologies, Inc., Morrisville, NC) and the dosimeters’ reading accuracy in the presence of wireless electromagnetic transponders inside a phantom.Methods: A custom-made, solid-water phantom was fabricated with space for transponders and dosimeters. Two inserts were machined with positioning grooves precisely matching the dimensions of the transponders and dosimeters and were arranged in orthogonal and parallel orientations, respectively. To test the transponder localization accuracy with∕without presence of dosimeters (hypothesis 1), multivariate analyses were performed on transponder-derived localization data with and without dosimeters at each preset distance to detect statistically significant localization differences between the control and test sets. To test dosimeter dose-reading accuracy with∕without presence of transponders (hypothesis 2), an approach of alternating the transponder presence in seven identical fraction dose (100 cGy) deliveries and measurements was implemented. Two-way analysis of variance was performed to examine statistically significant dose-reading differences between the two groups and the different fractions. A relative-dose analysis method was also used to evaluate transponder impact on dose-reading accuracy after dose-fading effect was removed by a second-order polynomial fit.Results: Multivariate analysis indicated that hypothesis 1 was false; there was a statistically significant difference between the localization data from the control and test sets. However, the upper and lower bounds of the 95% confidence intervals of the localized positional differences between the control and test sets were less than 0.1 mm, which was significantly smaller than the minimum

  8. A taxonomic revision of two local endemic Radix spp. (Gastropoda: Lymnaeidae) from Khodutka geothermal area, Kamchatka, Russian Far East.

    PubMed

    Bolotov, Ivan; Bespalaya, Yulia; Aksenova, Olga; Aksenov, Andrey; Bolotov, Nikita; Gofarov, Mikhail; Kondakov, Alexander; Paltser, Inga; Vikhrev, Ilya

    2014-01-01

    Khodutka geothermal area is located near Khodutka and Priemysh volcanoes and is one of the largest geothermal areas of the Kamchatka Peninsula. Vakin (2003) described geological, geochemical and geothermic conditions of this geothermal area in detail. The main thermal water sources have temperatures up to 87°C and a discharge of approximately 150 l×sec.-1 are flows out into the warm lake with dimensions of ca. 250 m length and 80 m width. This warm river is ca. 20 m in width beginning from the lake and flows to the Bolshaya Khodutka River basin. Two local endemic Radix species were described from this geothermal area, especially Lymnaea (Radix) hadutkae Kruglov & Starobogatov, 1989 and L. (R.) thermokamtschatica Kruglov & Starobogatov, 1989 (Kruglov & Starobogatov 1989, 1993; Kruglov 2005). These species were separated using proportions of shell and reproductive system (Kruglov & Starobogatov 1989, 1993; Starobogatov et al. 2004). According to the diagnosis, L. (R.) hadutkae differs in the ear-shape shell, a form of the provaginal duct with cylindrical distal part and conical proximal part, and larger value of the index of the copulatory apparatus (ICA: proportion of the preputium to phallotheca is 1.27) from other species within the section Thermoradix Kruglov & Starobogatov, 1989. The last whorl is large, 0.86-0.89 of the shell height; an excess of the last whorl over upper margin of the aperture is 0.15-0.16 of the aperture height. L. (R.) thermokamtschatica has the cylindrical provaginal duct, relatively short bursa duct (1.5X longer than the bursa copulatrix diameter) and very long phallotheca (ICA is 0.77). The last whorl is large, 0.85-0.87 of the shell height; an excess of the last whorl over upper margin of the aperture is 0.2-0.25 of the aperture height. In accordance with an identification key (Starobogatov et al. 2004), the main diagnostic feature is an excess of the last whorl over the shell aperture, which has ≤0.78 and ≥0.80 of the

  9. [Effect of Astragali Radix in improving early renal damage in metabolic syndrome rats through ACE2/Mas pathway].

    PubMed

    Wang, Qiong-ying; Liang, Wei; Jiang, Cheng; Li, Ning-yin; Xu, Han; Yang, Mi-na; Lin, Xin; Yu, Heng; Chang, Peng; Yu, Jing

    2015-11-01

    To study the expression of angiotensin converting enzyme 2 (ACE2) and angiotensin (Ang) 1-7 specific receptor Mas protain in renal blood vessels of metabolic syndrome ( MS) rats and its anti-oxidative effect. A total of 80 male SD rats were divided into four groups: the normal control group (NC, the same volume of normal saline), the MS group (high fat diet), the MS + Astragali Radix group (MS + HQ, 6 g x kg(-1) x d(-1) in gavage) and the MS + Valsartan group (MS + XST, 30 mg x kg(-1) x d(-1) in gavage). After four weeks of intervention, their general indexes, biochemical indexes and blood pressure were measured; plasma and renal tissue Ang II, malondialdehyde (MDA) and superoxide demutase (SOD) levels were measured with radioimmunoassay. The protein expressions of Mas receptor, AT1R, ACE and ACE2 were detected by western blot analysis. According to the result, compared with the NC group, the MS group and the MS + HQ group showed significant increases in systolic and diastolic pressures, body weight, fasting glucose, fasting insulin, triglycerides, free fatty acid and Ang II level of MS rats (P < 0.05). The MS + XST group showed notable decreases in systolic and diastolic pressures than that of the MS group. The MS group showed significant increases in the SOD activity and NO level and decrease in the MDA level after being intervened with Astragali Radix. ACE and AT1R protein expressions in renal tissues of the MS group were higher than that in the NC group, but with lower ACE2 and -Mas receptor expressions (all P < 0.05). Compared with the MS group, the MS + HQ group showed significant increase in Mas receptor expression in renal tissues, whereas the MS + XST group showed notable decrease in AT1R (all P < 0.05). In conclusion, Astragali Radix can increase the Mas receptor expressions in renal tissues, decrease ACE expression and change local Ang II, MDA, NO and SOD in kidneys, so as to protect early damages in renal tissues. PMID:27071265

  10. High thermoluminescent dosimeter readings outside a medical accelerator

    SciTech Connect

    Pollock, R.W.

    1985-09-01

    A doubling in personnel monitoring doses around medical accelerators has been reported when monthly film badges were changed to quarterly thermoluminescent (TL) dosimeters. One possible explanation for the inconsistent results is the response of LiF to thermal neutrons coming through the shielding around the accelerator. To test for this possibility seven pairs of TLD-100 and TLD-700 were taped to the outside of the door to a 20-MeV accelerator room and left for one month. The average net dose of the TLD-700 crystals (..gamma.. only) was 25 mrem. The TLD-100 crystals had a net response of 62 mrem, a significant over-response. Subtracting the ..gamma.. reading, the thermal neutron reading was 37 mrem. The TL relative response factor for thermal neutrons is 36. Dividing the neutron reading by the relative response factor yields a thermal neutron dose of 1 mrem. Thus the total dose was 26 mrem rather than the 62 mrem indicated by the TLD-100 crystals.

  11. Production of element correction factors for thermoluminescent dosimeters

    SciTech Connect

    Plato, P.; Miklos, J.

    1985-11-01

    Approximately 80 processors of personal dosimetry in the United States use thermoluminescent dosimeters (TLDs). Recent demands that dosimetry processors be able to measure radiation doses to within +/- 50% of the correct value have focused attention on the reproducibility of the TL elements within each TLD. The phosphors for these TLDs are manufactured by three companies. A dosimetry processor faces three options concerning the quality of the TL elements purchased; trust the supplier's quality control program, screen new TL elements and discard those that are extremely bad, or use element correction factors (ECFs). The first option results in dosimetry processors failing the +/- 50% accuracy requirement due to excessive variability among the TL elements. The second option still permits large precision errors that come close to the +/- 50% accuracy requirement. This paper advocates the third option and presents a 10-step procedure to produce ECFs. The procedure ensures that the ECFs represent only variations among the TL elements and not variations caused by stability problems with the TLD reader. Following is an example of ECF production for 3000 TLDs.

  12. Dose measurements in intraoral radiography using thermoluminescent dosimeters

    NASA Astrophysics Data System (ADS)

    Azorín, C.; Azorín, J.; Aguirre, F.; Rivera, T.

    2015-01-01

    The use of X-ray in medicine demands to expose the patient and the professional to the lowest radiation doses available in agreement with ALARA philosophy. The reference level for intraoral dental radiography is 7 mGy and, in Mexico, a number of examinations of this type are performed annually. It is considered that approximately 25% of all the X-rays examinations carried out in our country correspond to intraoral radiographies. In other hand, most of the intraoral X-ray equipment correspond to conventional radiological systems using film, which are developed as much manual as automatically. In this work the results of determining the doses received by the patients in intraoral radiological examinations made with different radiological systems using LiF:Mg,Cu,P+PTFE thermoluminescent dosimeters are presented. In some conventional radiological systems using film, when films are developed manual or automatically, incident kerma up to 10.61 ± 0.74 mGv were determined. These values exceed that reference level suggested by the IAEA and in the Mexican standards for intraoral examinations.

  13. Electron Beam Quality Determination Through Fricke Xylenol Gel Dosimeter

    SciTech Connect

    Petchevist, P. C. D.; Moreira, M. V.; Almeida, A. de

    2009-03-10

    According to the IAEA TRS-398 protocol, a parallel plate ionization chamber is recommended to be used in electron dosimetry. The important dosimetric parameters such as R{sub 100} and R{sub 50}, inferred from the percentage depth dose (PDD) curve, allow to obtain the electron beam average energy at the water phantom surface (material equivalent to the soft tissue). In this work, a chemical dosimeter based on the Fe(II) to Fe(III) oxidation was used to obtain the average energies from electrons beams (from nominal energies of 5, 8 and 10 MeV) and related parameters of R{sub 100}, R{sub 50} and z{sub ref}. These energies obtained through the Fricke Xylenol Gel (FXG) were compared to those with a parallel plate ionization chamber, following the cited protocol, which showed no significant differences. From these measurements one can conclude the FXG applicability for R{sub 100}, R{sub 50} and electron beam average energy determination.

  14. Characterization of power transistors as high dose dosimeters

    NASA Astrophysics Data System (ADS)

    Fuochi, P. G.; Lavalle, M.; Corda, U.; Kovacs, A.; Peimel-Stuglik, Z.; Gombia, E.

    2009-02-01

    A bipolar transistor, previously investigated as a possible radiation dosimeter and tested under industrial irradiation conditions in high-activity gamma and high-energy, high-power electron beam facilities has been subjected to stability test in order to understand its behaviour and help to improve its performances. Charge carrier lifetime was measured for several sets of transistors which were then irradiated with various doses (3-60 kGy): seven sets with 60Co gamma rays and eight with a 10 MeV electron beam. After irradiation all the transistors were measured and each set was divided into three groups: one group was left untreated, the second group was heated at 100 °C for 30 minutes and the third group was heated at 150 °C for 30 minutes, for testing the stability of the lifetime. Our data showed that heat treatment quite successfully eliminates post-irradiation changes in the response. Response measurements of the irradiated transistors, heat-treated and untreated, were carried out at room temperature over several weeks after irradiation to establish post-irradiation stability and assess if these transistors could be used for recording dose history. Calibration curves in the range 3-60 kGy for the thermally treated and untreated devices are presented. Dependence of the response of the transistors on the temperature of the measurements in the range 20-50 °C is reported.

  15. Thermoluminescent dosimeters for low dose X-ray measurements.

    PubMed

    Fernández, S Del Sol; García-Salcedo, R; Sánchez-Guzmán, D; Ramírez-Rodríguez, G; Gaona, E; de León-Alfaro, M A; Rivera-Montalvo, T

    2016-01-01

    The response of TLD-100, CaSO4:Dy and LiF:Mg,Cu,P for a range of X-ray low dose was measured. For calibration, the TLDs were arranged at the center of the X-ray field. The dose output of the X-ray machine was determined using an ACCU-Gold. All dosimeters were exposed at the available air kerma values of 14.69 mGy within a field 10×10 cm(2) at 80 cm of SSD. Results of LiF:Mg,Cu,P X-ray irradiated showed 4.8 times higher sensitivity than TLD-100. Meanwhile, TL response of CaSO4:Dy exposed at the same dose was 5.6 time higher than TLD-100. Experimental results show for low dose X-ray measurements a better linearity for LiF:Mg,Cu,P compared with that of TLD-100. CaSO4:Dy showed a linearity from 0.1 to 60 mGy. PMID:26609683

  16. A small active dosimeter for applications in space

    NASA Astrophysics Data System (ADS)

    Ritter, Birgit; Maršálek, Karel; Berger, Thomas; Burmeister, Sönke; Reitz, Günther; Heber, Bernd

    2014-06-01

    The radiation field in low Earth orbits (LEO) differs significantly from the radiation environment on Earth's surface. Exposures are by far higher and pose an additional health risk for astronauts. Continuous monitoring is therefore a necessary task in the frame of radiation protection measures. A small battery-driven active dosimeter telescope based on silicon detectors meeting the requirements for LEO applications has been developed. The instrument, the Mobile Dosimetric Telescope (MDT), is designed to measure the absorbed dose rate and the linear energy transfer (LET) spectra. From the latter the mean quality factor of the radiation field can be derived and hence an estimate of the dose equivalent as a measure of the exposure. The calibration of the device is done using radioactive isotopes and heavy ions. Fragmentation products of heavy ions are used to show the ability of the MDT to reliably detect energy depositions from high energetic nuclei. Radiation measurements inside aircraft during long distance flights, serving as field tests of the instrument, prove the good performance of the instrument.

  17. Dosimetric characteristics of a MOSFET dosimeter for clinical electron beams.

    PubMed

    Manigandan, D; Bharanidharan, G; Aruna, P; Devan, K; Elangovan, D; Patil, Vikram; Tamilarasan, R; Vasanthan, S; Ganesan, S

    2009-09-01

    The fundamental dosimetric characteristics of commercially available metal oxide semiconductor field effect transistor (MOSFET) detectors were studied for clinical electron beam irradiations. MOSFET showed excellent linearity against doses measured using an ion chamber in the dose range of 20-630cGy. MOSFET reproducibility is better at high doses compared to low doses. The output factors measured with the MOSFET were within +/-3% when compared with those measured with a parallel plate chamber. From 4 to 12MeV, MOSFETs showed a large angular dependence in the tilt directions and less in the axial directions. MOSFETs do not show any dose-rate dependence between 100 and 600MU/min. However, MOSFETs have shown under-response when the dose per pulse of the beam is decreased. No measurable effect in MOSFET response was observed in the temperature range of 23-40 degrees C. The energy dependence of a MOSFET dosimeter was within +/-3.0% for 6-18MeV electron beams and 5.5% for 4MeV ones. This study shows that MOSFET detectors are suitable for dosimetry of electron beams in the energy range of 4-18MeV. PMID:19128995

  18. Feasibility Study of Glass Dosimeter for In Vivo Measurement: Dosimetric Characterization and Clinical Application in Proton Beams

    SciTech Connect

    Rah, Jeong-Eun; Oh, Do Hoon; Kim, Jong Won; Kim, Dae-Hyun; Suh, Tae-Suk; Ji, Young Hoon; Shin, Dongho; Lee, Se Byeong; Kim, Dae Yong; Park, Sung Yong

    2012-10-01

    Purpose: To evaluate the suitability of the GD-301 glass dosimeter for in vivo dose verification in proton therapy. Methods and Materials: The glass dosimeter was analyzed for its dosimetrics characteristic in proton beam. Dosimeters were calibrated in a water phantom using a stairlike holder specially designed for this study. To determine the accuracy of the glass dosimeter in proton dose measurements, we compared the glass dosimeter and thermoluminescent dosimeter (TLD) dose measurements using a cylindrical phantom. We investigated the feasibility of the glass dosimeter for the measurement of dose distributions near the superficial region for proton therapy plans with a varying separation between the target volume and the surface of 6 patients. Results and Discussion: Uniformity was within 1.5%. The dose-response has good linearity. Dose-rate, fading, and energy dependence were found to be within 3%. The beam profile measured using the glass dosimeter was in good agreement with the profile obtained from the ionization chamber. Depth-dose distributions in nonmodulated and modulated proton beams obtained with the glass dosimeter were estimated to be within 3%, which was lower than those with the ionization chamber. In the phantom study, the difference of isocenter dose between the delivery dose calculated by the treatment planning system and that measured by the glass dosimeter was within 5%. With in vivo dosimetry, the calculated surface doses overestimated measurements by 4%-16% using glass dosimeter and TLD. Conclusion: It is recommended that bolus be added for these clinical cases. We also believe that the glass dosimeter has considerable potential for use with in vivo patient proton dosimetry.

  19. A Chinese Herbal Decoction, Dang Gui Bu Xue Tang, Prepared from Radix Astragali and Radix Angelicae sinensis, Ameliorates Insulin Resistance Induced by A High-Fructose Diet in Rats

    PubMed Central

    Liu, I-Min; Tzeng, Thing-Fong; Liou, Shorong-Shii

    2011-01-01

    Dang Gui Bu Xue Tang (DBT), a Chinese medicinal decoction contains Radix Angelicae sinensis (Danggui) and Radix Astragali (Huangqi) at a ratio of 1 : 5, is used commonly for treating women's ailments. This study was conducted to explore the effects of this preparation on insulin resistance in rats fed with 6-week diet containing 60% fructose. Similar to the action of rosiglitazone (4 mg kg−1 per day by an oral administration), repeated oral administration of DBT (2.5 g kg−1 per day) for 14 days was found to significantly alleviate the hyperglycemia but made no influence on plasma lipid profiles nor weight gain in fructose chow-fed rats. Also, the higher degree of insulin resistance as measured by homeostasis model assessment of basal insulin resistance in fructose chow-fed rats was significantly decreased by repeated DBT treatment. DBT displays the characteristic of rosiglitazone by increasing the whole-body insulin sensitivity in fructose chow-fed rats after 2-week treatment, as evidenced by the marked elevation of composite whole-body insulin sensitivity index during the oral glucose tolerance test. DBT improves insulin sensitivity through increased post-receptor insulin signaling mediated by enhancements in insulin receptor substrate-1-associated phosphatidylinositol 3-kinase step and glucose transporter subtype 4 translocation in soleus muscles of animals exhibiting insulin resistance. DBT is therefore proposed as potentially useful adjuvant therapy for patients with insulin resistance and/or the patients who wish to increase insulin sensitivity. PMID:19233878

  20. Field calibrations of a long-term UV dosimeter for aquatic UVB exposures.

    PubMed

    Schouten, P W; Parisi, A V; Turnbull, D J

    2008-05-29

    Various methodologies using a wide range of measurement systems have been employed previously in order to determine the amount of UV that could be incident upon various aquatic organisms in a number of different aquatic locales. Broadband meters and spectroradiometers have been employed extensively to take underwater measurements. However, these measurement campaigns are limited by the fact that radiometric equipment requires a human controller, constant power supply and regular calibrations and corrections in order to function properly. Dosimetric measurements have also been made underwater using two distinct types of dosimeter. The first type based on a synthetic chemical, like polysulphone, and the second type based on a biological matter, such as a DNA sample. The studies made using biological dosimeters have displayed very good results, however the time and skill necessary to make these types of dosimeters can outweigh their usefulness. The chemical dosimeters are easier to make and have also provided useable data, but only for short periods of exposure, usually no more than a day. Previous research has shown that Poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) has excellent potential for use as a long-term underwater solar UVB dosimeter. However, there is no documented methodology on how to properly calibrate the PPO dosimeter for water-based measurements and it has yet to be trialled in an outdoors marine environment, either real or simulated. This manuscript shows that calibrations obtained in air can not be transferred to calibrations made in water, calibrations made in one type of water can be employed for another type of water, but only within a certain range of spectral transmission and calibrations made at different depths in the same water type are interchangeable. It was also discovered that changing solar zenith angle had an effect upon calibration data. This research addressed these issues by formulating and developing a calibration methodology

  1. Dual calibrated dosimeter for simultaneous measurements of erythemal and vitamin D effective solar ultraviolet radiation.

    PubMed

    Wainwright, L; Parisi, A V; Downs, N

    2016-04-01

    A miniaturized ultraviolet radiation (UV) dosimeter based on polyphenylene oxide (PPO) has been dual calibrated for both erythemal and vitamin D effective exposures (UVB 280 - 320 nm) over extended periods up to five days. Optimal human health requires a balanced amount of UVB exposure as both too much and too little have different but serious potential health consequences. Dosimetry is an established method of measuring specific UV exposures to an object or subject. PPO dosimeters have previously been used to measure the erythemally effective UV exposure. An extension of this use is to dual calibrate the miniaturized dosimeter which will also enable measurement of vitamin D effective exposures. By calibration to the erythemal and vitamin D effective action spectra, PPO dosimeters were able to record both types of biologically effective exposure as both are active within the UVB waveband. Dose response tests were conducted in each season by exposure to solar UV with the corresponding dual calibrations made for each season. The calibration provided an R(2) of 0.95-0.99 for erythemal UV and an R(2) of 0.99 for vitamin D effective UV. The successful outcome of this testing has established that PPO is suitable for use as a long term, dual calibrated dosimeter provided the film is seasonally calibrated. This enables one dosimeter to provide two sets of exposure results. The combination of dual calibration and the long term exposure potential of PPO makes the PPO dosimeter more versatile and increases the scope of UV field research on erythemal UV and vitamin D effective UV in the future. PMID:26878218

  2. SU-E-T-368: Effect of a Strong Magnetic Field On Select Radiation Dosimeters

    SciTech Connect

    Mathis, M; Wen, Z; Tailor, R; Sawakuchi, G; Flint, D; Beddar, S; Ibbott, G

    2014-06-01

    Purpose: To determine the effect of a strong magnetic field on TLD-100, OSLD (Al{sub 2}O{sub 2}:C), and PRESAGE dosimetry devices. This study will help to determine which types of dosimeters can be used for quality assurance and in-vivo dosimetry measurements in a magnetic resonance imaginglinear accelerator (MRI-linac) system. Methods: The dosimeters were separated into two categories which were either exposed or not exposed to a strong magnetic field. In each category a set of dosimeters was irradiated with 0, 2, or 6 Gy. To expose the dosimeters to a magnetic field the samples in that category were place in a Bruker small animal magnetic resonance scanner at a field strength slightly greater than 2.5 T for at least 1 hour preirradiation and at least 1 hour post-irradiation. Irradiations were performed with a 6 MV x-ray beam from a Varian TrueBeam linac with 10×10 cm{sup 2} field at a 600 MU/min dose rate. The samples that received no radiation dose were used as control detectors. Results: The readouts of the dosimeters which were not exposed to a strong magnetic field were compared with the measurements of the dosimetry devices which were exposed to a magnetic field. No significant differences (less than 2% difference) in the performance of TLD, OSLD, or PRESAGE dosimeters due to exposure to a strong magnetic field were observed. Conclusion: Exposure to a strong magnetic field before and after irradiation does not appear to change the dosimetric properties of TLD, OSLD, or PRESAGE which indicates that these dosimeters have potential for use in quality assurance and in-vivo dosimetry in a MRI-linac. We plan to further test the effect of magnetic fields on these devices by irradiating them in the presence of a magnetic fields similar to those produced by a MRI-linac system. Elekta-MD Anderson Cancer Center Research Agreement.

  3. Study of a non-diffusing radiochromic gel dosimeter for 3D radiation dose imaging

    NASA Astrophysics Data System (ADS)

    Marsden, Craig Michael

    2000-12-01

    This thesis investigates the potential of a new radiation gel dosimeter, based on nitro-blue tetrazolium (NBTZ) suspended in a gelatin mold. Unlike all Fricke based gel dosimeters this dosimeter does not suffer from diffusive loss of image stability. Images are obtained by an optical tomography method. Nitro blue tetrazolium is a common biological indicator that when irradiated in an aqueous medium undergoes reduction to a highly colored formazan, which has an absorbance maximum at 525nm. Tetrazolium is water soluble while the formazan product is insoluble. The formazan product sticks to the gelatin matrix and the dose image is maintained for three months. Methods to maximize the sensitivity of the system were evaluated. It was found that a chemical detergent, Triton X-100, in combination with sodium formate, increased the dosimeter sensitivity significantly. An initial G-value of formazan production for a dosimeter composed of 1mM NBTZ, gelatin, and water was on the order of 0.2. The addition of Triton and formate produced a G-value in excess of 5.0. The effects of NBTZ, triton, formate, and gel concentration were all investigated. All the gels provided linear dose vs. absorbance plots for doses from 0 to >100 Gy. It was determined that gel concentration had minimal if any effect on sensitivity. Sensitivity increased slightly with increasing NBTZ concentration. Triton and formate individually and together provided moderate to large increases in dosimeter sensitivity. The dosimeter described in this work can provide stable 3D radiation dose images for all modalities of radiation therapy equipment. Methods to increase sensitivity are developed and discussed.

  4. Management of Complex Root Canal Curvature of Bilateral Radix Entomolaris: Three-Dimensional Analysis with Cone Beam Computed Tomography

    PubMed Central

    Mahendra, Muktishree; Verma, Anand; Tyagi, Sanjeev; Singh, Santosh; Malviya, Kapil; Chaddha, Ramit

    2013-01-01

    The meticulous knowledge of anatomic characteristics and their variations is essential for the clinician. Radix entomolaris (RE) is one such anomaly where an extra root is present on the distolingual aspect of the mandibular first molar. 18-year-old patient was referred for the root canal treatment of mandibular right and left first molars. Intraoral periapical radiograph revealed additional periodontal spacing crossing distal root of 36. A CBCT was advised and it confirmed the presence of extra roots both in 36 and 46. CBCT is useful in endodontics as it aids in the identification of essential anatomic structures and determination of radius and angle of root canal curvature which is linked to fracture of the instrument. The classical triangular access cavity was modified to a trapezoidal form to locate the extra canal. All canals were instrumented with controlled memory nickel titanium instruments and obturation was done with single cone technique. PMID:24455320

  5. Color stability of white organic light emitting devices with a color conversion layer utilizing CdSe/ZnS quantum dots and phosphors dispersed in polymethylmethacrylate.

    PubMed

    Kwon, W J; Kim, S H; Lee, K S; Choo, D C; Kim, S W; Kim, S W; Yoo, T W; Kwon, M S; Yoo, K H; Kim, T W

    2013-06-01

    White organic light-emitting devices (WOLEDs) were fabricated by combining a blue emitting organic light-emitting devices (OLEDs) and a color conversion layer made of yttrium aluminum garnet phosphors and CdSe/ZnS quantum dots (QDs) embedded into polymethylmethacrylate. When the ratio of phosphors and QDs changed, a good color balance was achieved at a ratio of 1:5, and the maximum luminance of 18.21 cd/m2 was obtained. As the applied voltage varied from 12 to 16 V, Commission Internationale de l'Eclairage coordinates shifted only slightly from (0.32, 0.34) to (0.30, 0.33), indicating a good color stability. PMID:23862508

  6. Rapid Determination of Puerarin by Near-infrared Spectroscopy During Percolation and Concentration Process of Puerariae Lobatae Radix

    PubMed Central

    Jintao, Xue; Quanwei, Yang; Yun, Jing; Yufei, Liu; Chunyan, Li; Jing, Yang; Yanfang, Wu; Peng, Li; Guangrui, Wan

    2016-01-01

    Background: Gegen (Puerariae Labatae Radix) is one of the important medicines in Traditional Chinese Medicine. The studies showed that Gegen and its preparation had effective actions for atherosclerosis. Objective: Near-infrared (NIR) was used to develop a method for rapid determination of puerarin during percolation and concentration process of Gegen. Materials and Methods: About ten batches of samples were collected with high-performance liquid chromatography analysis values as reference, calibration models are generated by partial least-squares (PLS) regression as linear regression, and artificial neural networks (ANN) as nonlinear regression. Results: The root mean square error of prediction for the PLS and ANN model was 0.0396 and 0.0365 and correlation coefficients (r2) was 97.79% and 98.47%, respectively. Conclusions: The NIR model for the rapid analysis of puerarin can be used for on-line quality control in the percolation and concentration process. SUMMARY Near-infrared was used to develop a method for on-line quality control in the percolation and concentration process of GegenCalibration models are generated by partial least-squares (PLS) regression as linear regression and artificial neural networks (ANN) as non-linear regressionThe root mean square error of prediction for the PLS and ANN model was 0.0396 and 0.0365 and correlation coefficients (r2) was 97.79% and 98.47%, respectively. Abbreviations used: NIR: Near-Infrared Spectroscopy; Gegen: Puerariae Loabatae Radix; TCM: Traditional Chinese Medicine; PLS: Partial least-squares; ANN: Artificial neural networks; RMSEP: Root mean square error of validation; R2: Correlation coefficients; PAT: Process analytical technology; FDA: The Food and Drug Administration; Rcal: Calibration set; RMSECV: Root mean square errors of cross-validation; RPD: Residual predictive deviation; SLS: Straight Line Subtraction; MLP: Multi-Layer Perceptron; MSE: Mean square error. PMID:27601848

  7. TH-C-19A-05: Evaluation of a New Reusable 3D Dosimeter

    SciTech Connect

    Juang, T; Adamovics, J; Oldham, M

    2014-06-15

    Purpose: PRESAGE is a radiochromic plastic which has demonstrated strong potential for high resolution single-use 3D dosimetry. This study evaluates a new PRESAGE formulation (Presage-RU) in which the radiochromic response is reversible (the dosimeter optically clears after irradiation), enabling the potential for reusability. Methods: Presage-RU dose response and optical-clearing rates were evaluated in both small volume dosimeters (1×1×4.5cm) and a larger cylindrical dosimeter (8cm diameter, 4.5cm length). All dosimeters were allowed to fully optically clear in dark, room temperature conditions between irradiations. Dose response was determined by irradiating small volume samples from 0–8.0Gy and measuring change in optical density. The cylindrical dosimeter was irradiated with a simple 4-field box plan (parallel opposed pairs of 4cm×4cm AP-PA beams and 2cm×4cm lateral beams) to 20Gy. High resolution 3D dosimetry was achieved utilizing optical-CT readout. Readings were tracked up to 14 days to characterize optical clearing. Results: Initial irradiation yielded a response of 0.0119△OD/(Gy*cm) while two subsequent reirradiations yielded a lower but consistent response of 0.0087△OD/(Gy*cm). Strong linearity of dose response was observed for all irradiations. In the large cylindrical dosimeter, the integral dose within the high dose region exhibited an exponential decay in signal over time (halflife= 23.9 hours), with the dosimeter effectively cleared (0.04% of the initial signal) after 10 days. Subsequent irradiation resulted in 19.5% lower initial signal but demonstrated that the exponential clearing rate remained consistent. Results of additional subsequent irradiations will also be presented. Conclusion: This work introduces a new re-usable radiochromic dosimeter (Presage-RU) compatible with high resolution (sub-millimeter) 3D dosimetry. Sensitivity of the initial radiation was observed to be slightly higher than subsequent irradiations, but the

  8. The characterization of a commercial MOSFET dosimeter system for use in diagnostic x ray.

    PubMed

    Bower, M W; Hintenlang, D E

    1998-08-01

    A commercial patient dose verification system utilizing non-invasive metal oxide semiconductor field effect transistor (MOSFET) dosimeters originally designed for radiotherapy applications has been evaluated for use at diagnostic energy levels. The system features multiple dosimeters that may be used to monitor entrance or exit skin dose and intracavity doses in phantoms in real time. We have characterized both the standard MOSFET dosimeter designed for radiotherapy dose verification and a newly developed "high sensitivity" MOSFET dosimeter designed for lower dose measurements. The sensitivity, linearity, angular response, post-exposure response, and physical characteristics were evaluated. The average sensitivity (free in air, including backscatter) of the radiotherapy MOSFET dosimeters ranged from 3.55 x 10(4) mV per C kg(-1) (9.2 mV R(-1)) to 4.87 x 10(4) mV per C kg(-1) (12.6 mV R(-1)) depending on the energy of the x-ray field. The sensitivity of the "high sensitivity" MOSFET dosimeters ranged from 1.15 x 10(5) mV per C kg(-1) (29.7 mV R(-1)) to 1.38 x 10(5) mV per C kg(-1) (35.7 mV R(-1)) depending on the energy of the x-ray field. The high sensitivity dosimeters demonstrated excellent linearity at high energies (90 and 120 kVp) and acceptable linearity at lower energies (60 kVp). The angular response was significant for free-in-air exposures, as illustrated by the sensitivity differences between the two sides of the dosimeter, but was excellent for measurements within a tissue equivalent cylinder. The post-exposure drift response is a complicated but reproducible function of time. Real-time monitoring requires little if any corrections for the post-exposure drift response. The MOSFET dosimeter system brings some unique capabilities to diagnostic radiology dosimetry including small size, real-time capabilities, nondestructive measurement, good linearity, and a predictable angular response. PMID:9685076

  9. Dose rate dependence for different dosimeters and detectors: TLD, OSL, EBT films, and diamond detectors

    SciTech Connect

    Karsch, L.; Beyreuther, E.; Burris-Mog, T.; Kraft, S.; Richter, C.; Zeil, K.; Pawelke, J.

    2012-05-15

    Purpose: The use of laser accelerators in radiation therapy can perhaps increase the low number of proton and ion therapy facilities in some years due to the low investment costs and small size. The laser-based acceleration technology leads to a very high peak dose rate of about 10{sup 11} Gy/s. A first dosimetric task is the evaluation of dose rate dependence of clinical dosimeters and other detectors. Methods: The measurements were done at ELBE, a superconductive linear electron accelerator which generates electron pulses with 5 ps length at 20 MeV. The different dose rates are reached by adjusting the number of electrons in one beam pulse. Three clinical dosimeters (TLD, OSL, and EBT radiochromic films) were irradiated with four different dose rates and nearly the same dose. A faraday cup, an integrating current transformer, and an ionization chamber were used to control the particle flux on the dosimeters. Furthermore two diamond detectors were tested. Results: The dosimeters are dose rate independent up to 410{sup 9} Gy/s within 2% (OSL and TLD) and up to 1510{sup 9} Gy/s within 5% (EBT films). The diamond detectors show strong dose rate dependence. Conclusions: TLD, OSL dosimeters, and EBT films are suitable for pulsed beams with a very high pulse dose rate like laser accelerated particle beams.

  10. FlexyDos3D: a deformable anthropomorphic 3D radiation dosimeter: radiation properties

    NASA Astrophysics Data System (ADS)

    De Deene, Y.; Skyt, P. S.; Hil, R.; Booth, J. T.

    2015-02-01

    Three dimensional radiation dosimetry has received growing interest with the implementation of highly conformal radiotherapy treatments. The radiotherapy community faces new challenges with the commissioning of image guided and image gated radiotherapy treatments (IGRT) and deformable image registration software. A new three dimensional anthropomorphically shaped flexible dosimeter, further called ‘FlexyDos3D’, has been constructed and a new fast optical scanning method has been implemented that enables scanning of irregular shaped dosimeters. The FlexyDos3D phantom can be actuated and deformed during the actual treatment. FlexyDos3D offers the additional advantage that it is easy to fabricate, is non-toxic and can be molded in an arbitrary shape with high geometrical precision. The dosimeter formulation has been optimized in terms of dose sensitivity. The influence of the casting material and oxygen concentration has also been investigated. The radiophysical properties of this new dosimeter are discussed including stability, spatial integrity, temperature dependence of the dosimeter during radiation, readout and storage, dose rate dependence and tissue equivalence. The first authors Y De Deene and P S Skyt made an equivalent contribution to the experimental work presented in this paper.

  11. Applicability of the polyphenylene oxide film dosimeter to high UV exposures in aquatic environments.

    PubMed

    Schouten, P W; Parisi, A V; Turnbull, D J

    2009-09-01

    Previous research has proven that the Poly (2,6-dimethyl-1, 4-phenylene oxide) (PPO) dosimeter is capable of receiving both in-air and underwater UV exposures that are significantly greater than those of the more commonly used polysulphone dosimeter, within a range of accuracy close to what would be expected of dosimetric measurements made in-air provided that the necessary calibrations are completed correctly by factoring in different atmospheric column ozone levels, SZA ranges, varying water turbidity and DOM levels. However, there is yet to be an investigation detailing the performance of the PPO dosimeter and its ability to measure UV in an actual field environment over an extended period of time. This research aims to bridge this gap in the knowledge by presenting a measurement campaign carried out in two real world aquatic environments and a simulated sea water environment using a batch of PPO dosimeters set at different depths and aligned to a range of different angles and geographical directions by means of attachment to a custom built dosimeter submersible float (DSF) unit over the space of a year at a sub-tropical location. Results obtained from this measurement campaign were used to compute a K(d) value for the sea water in each particular season. These K(d) values where found to be in close agreement to standalone K(d) values derived from results taken using a standard calibrated spectrometer in the same sea water. PMID:19596202

  12. Undoped and doped poly(tetraphenylbenzidine) as sensitive material for an impedimetric nitrogen dioxide gas dosimeter

    SciTech Connect

    Marr, I.; Moos, R.; Neumann, K.; Thelakkat, M.

    2014-09-29

    This article presents a nitrogen dioxide (NO{sub 2}) detecting gas dosimeter based on poly(tetraphenylbenzidine) poly(TPD) as nitrogen oxide (NO{sub x}) sensitive layer. Gas dosimeters are suitable devices to determine reliably low levels of analytes over a long period of time. During NO{sub x} exposure, the analyte molecules are accumulated irreversibly in the sensing layer of the dosimeter enhancing the conductivity of the hole conducting poly(TPD), which can be measured by impedance spectroscopy. Due to their possibility for low cost production by simple printing techniques and very good physical, photochemical, and electrochemical properties, poly(TPD)s are suitable for application in gas dosimeters operated at room temperature. We studied the effect of doping with a Co(III)-complex in combination with a conducting salt on the dosimeter behavior. Compared to the undoped material, a strong influence of the doping can be observed: the conductivity of the sensing material increases significantly, the noise of the signal decreases and an unwanted recovery of the sensor signal can be prevented, leading to a NO{sub x} detection limit <10 ppm.

  13. Development of new two-dosimeter algorithm for effective dose in ICRP Publication 103.

    PubMed

    Kim, Chan Hyeong; Cho, Sungkoo; Jeong, Jong Hwi; Bolch, Wesley E; Reece, Warren D; Poston, John W

    2011-05-01

    The two-dosimeter method, which employs one dosimeter on the chest and the other on the back, determines the effective dose with sufficient accuracy for complex or unknown irradiation geometries. The two-dosimeter method, with a suitable algorithm, neither significantly overestimates (in most cases) nor seriously underestimates the effective dose, not even for extreme exposure geometries. Recently, however, the definition of the effective dose itself was changed in ICRP Publication 103; that is, the organ and tissue configuration employed in calculations of effective dose, along with the related tissue weighting factors, was significantly modified. In the present study, therefore, a two-dosimeter algorithm was developed for the new ICRP 103 definition of effective dose. To that end, first, effective doses and personal dosimeter responses were calculated using the ICRP reference phantoms and the MCNPX code for many incident beam directions. Next, a systematic analysis of the calculated values was performed to determine an optimal algorithm. Finally, the developed algorithm was tested by applying it to beam irradiation geometries specifically selected as extreme exposure geometries, and the results were compared with those for the previous algorithm that had been developed for the effective dose given in ICRP Publication 60. PMID:21451315

  14. Photofission Analysis for Fissile Dosimeters Dedicated to Reactor Pressure Vessel Surveillance

    NASA Astrophysics Data System (ADS)

    Bourganel, Stéphane; Faucher, Margaux; Thiollay, Nicolas

    2016-02-01

    Fissile dosimeters are commonly used in reactor pressure vessel surveillance programs. In this paper, the photofission contribution is analyzed for in-vessel 237Np and 238U fissile dosimeters in French PWR. The aim is to reassess this contribution using recent tools (the TRIPOLI-4 Monte Carlo code) and latest nuclear data (JEFF3.1.1 and ENDF/B-VII nuclear libraries). To be as exhaustive as possible, this study is carried out for different configurations of fissile dosimeters, irradiated inside different kinds of PWR: 900 MWe, 1300 MWe, and 1450 MWe. Calculation of photofission rate in dosimeters does not present a major problem using the TRIPOLI-4® Monte Carlo code and the coupled neutron-photon simulation mode. However, preliminary studies were necessary to identify the origin of photons responsible of photofissions in dosimeters in relation to the photofission threshold reaction (around 5 MeV). It appears that the main contribution of high enough energy photons generating photofissions is the neutron inelastic scattering in stainless steel reactor structures. By contrast, 137Cs activity calculation is not an easy task since photofission yield data are known with high uncertainty.

  15. Eliminating the dose-rate effect in a radiochromic silicone-based 3D dosimeter

    NASA Astrophysics Data System (ADS)

    Høye, E. M.; Balling, P.; Yates, E. S.; Muren, L. P.; Petersen, J. B. B.; Skyt, P. S.

    2015-07-01

    Comprehensive dose verification, such as 3D dosimetry, may be required for safe introduction and use of advanced treatment modalities in radiotherapy. A radiochromic silicone-based 3D dosimetry system has recently been suggested, though its clinical use has so far been limited by a considerable dose-rate dependency of the dose response. In this study we have investigated the dose-rate dependency with respect to the chemical composition of the dosimeter. We found that this dependency was reduced with increasing dye concentration, and the dose response was observed to be identical for dosimeters irradiated with 2 and 6 Gy min-1 at concentrations of 0.26% (w/w) dye and 1% (w/w) dye solvent. Furthermore, for the optimized dosimeter formulation, no dose-rate effect was observed due to the attenuation of the beam fluence with depth. However, the temporal stability of the dose response decreased with dye concentration; the response was reduced by (62  ±  1)% within approximately 20 h upon irradiation, at the optimal chemical composition and storage at room temperature. In conclusion, this study presents a chemical composition for a dose-rate independent silicone dosimeter which has considerably improved the clinical applicability of such dosimeters, but at the cost of a decreased stability.

  16. Investigation on Tissue Equivalent Normoxic Polymer Gel Dosimeter using In-house Laser CT scanning system

    NASA Astrophysics Data System (ADS)

    Senthil Kumar, D.; Jebaseelan Samuel, E. James

    2010-11-01

    Optical Computed Tomography has wide applications in the treatment of cancer. In continuation of this, an in-house Laser CT scanner has been built for "3D gel dosimetry". The Laser CT (LCT) scanner plays a major for Gel dosimeter or phantom readout and in clinical radiation therapy as a 3-Dimensional Radiation Dosimetry. A gel dosimeter which absorbs dose in a tissue-equivalent manner and allows the measurement of spatial distribution of the deposited dose is required. The normoxic PAGAT (Polyacrylamide Gelatin and Tetrakis) gel is used as a dosimeter for this analysis. When laser passes through this gel phantom, absorption and scattering takes place and combined to attenuation. The optical attenuation coefficient of the laser can be obtained by measuring its intensity after passing through the gel by means of a sensor. Reconstruction using Mat Lab algorithm provides 3D dose distribution.

  17. A multi-sensor dosimeter for brachytherapy based on radioluminescent fiber sensors

    NASA Astrophysics Data System (ADS)

    Correia, A.; Chiquita, S.; Hussain, N. Sooraj; Pirraco, Rui; Rosa, C. C.

    2013-05-01

    High-precision dosimeters are needed in brachytherapy treatments to ensure safe operation and adequate working conditions, to assess the correspondence between treatment planning and dose delivery, as well as to monitor the radiation dose received by patients. In this paper we present the development of a multi-sensor dosimeter platform targeted for brachytherapy environments. The performance of different scintillating materials response is assessed. The emission bands of most common scintillator materials used in ionizing radiation detection are typically below 550 nm, thus they may be prone to stem effect response. To avoid this effect we propose the use of scintillators with longer wavelength emission. Samples of neodymium doped glasses are evaluated as new infrared radioluminescent scintillators for real-time dosimeters, namely lithium lead boron silver (LLB4Ag) and lithium bismuth boron silver (LBiB4Ag) glasses. Their response is compared with the response of organic scintillator BCF-60 with a 530nm response.

  18. Radio-physical properties of micelle leucodye 3D integrating gel dosimeters

    NASA Astrophysics Data System (ADS)

    Vandecasteele, J.; Ghysel, S.; Baete, S. H.; De Deene, Y.

    2011-02-01

    Recently, novel radiochromic leucodye micelle hydrogel dosimeters were introduced in the literature. In these studies, gel measured electron depth dose profiles were compared with ion chamber depth dose data, from which it was concluded that leucocrystal violet-type dosimeters were independent of dose rate. Similar conclusions were drawn for leucomalachite green-type dosimeters, only after pre-irradiating the samples to a homogeneous radiation dose. However, in our extensive study of the radio-physical properties of leucocrystal violet- and leucomalachite green-type dosimeters, a significant dose rate dependence was found. For a dose rate variation between 50 and 400 cGy\\,min^{-1}, a maximum difference of 75% was found in optical dose sensitivity for the leucomalachite green-type dosimeter. Furthermore, the measured optical dose sensitivity of the leucomalachite green-type dosimeter was four times lower than the value previously reported in the literature. For the leucocrystal violet-type dosimeter, a maximum difference in optical dose sensitivity of 55% was found between 50 and 400 cGy\\,min^{-1}. A modified composition of the leucomalachite green-type dosimeter is proposed. This dosimeter is composed of gelatin, sodium dodecyl sulfate, chloroform, trichloroacetic acid and leucomalachite green. The optical dose sensitivity amounted to 4.375 \\times 10^{-5} \\,cm^{-1}\\; cGy^{-1} (dose rate 400 cGy\\,min^{-1}). No energy dependence for photon energies between 6 and 18 MV was found. No temperature dependence during readout was found notwithstanding a temperature dependence during irradiation of 1.90 cGy °C-1 increase on a total dose of 100 cGy. The novel gel dosimeter formulation exhibits an improved spatial stability (2.45 \\times 10^{-7} \\,cm^{2}\\; s^{-1} (= 0.088 mm^2 \\; h^{-1})) and good water/soft tissue equivalence. Nevertheless, the novel formulation was also found to have a significant, albeit reduced, dose rate dependence, as a maximum difference of 33

  19. The study of N-isopropylacrylamide gel dosimeter doped iodinated contrast agents

    NASA Astrophysics Data System (ADS)

    Chang, Y. J.; Hsieh, L. L.; Liu, M. H.; Liu, J. S.; Hsieh, B. T.

    2013-06-01

    Low toxicity of N-isopropylacrylamide (NIPAM) dosimeter was doped with clinical iodinated contrast medium agents(Iobitridol (Xenetix® 350) and organically bound iodine (Conray® 60) as radiation sensitizers; The suitable gel dosimeter preparation formula in this research was 5 w/w% gelatin, 5 w/w% N-isopropylacrylamide, 3 w/w% N,N-methylene-bis-acrylamide, and 5 mM Tetrakis phosphonium chloride. The spiral CT was irradiator, and 120 kVp was the operating tube voltage. The maximum radiation dose was 0.6 Gy, and optical CT was the gel measurement device used. The results showed SERs with the addition of radiosensitizers were 10.70 (Xenetix® 350) and 9.67 (Conray® 60), respectively. Thus, the polymerized gel dosimeter could be used in the efficacy evaluation of low-energy and low-radiation dose.

  20. Thermal neutron response of the Li 2B 4O 7:Cu TL dosimeter

    NASA Astrophysics Data System (ADS)

    Gauld, I. C.; Harvey, J. W.; Kennett, T. J.; Prestwich, W. V.

    1986-10-01

    A measurement of the thermal neutron response of the Li 2B 4O 7:Cu TLD has been conducted. The results obtained using the Panasonic UD-806 dosimeter and UD-854A holder yield a free-in-air response of 3.3±0.1 R 60Co equivalent per mSv of thermal neutrons. A thermal neutron response of over 7 R 60Co equivalent per mSv was observed when the dosimeter was irradiated on water phantoms. The high sensitivity may result in a substantial overestimate of the gamma dose equivalent if the TLD is used in a mixed neutron and gamma environment of unknown ratio. Measurements of the Li 2B 4O 7:Cu glow curve, TL saturation curve and the thermal neutron response dependence of the dosimeter filtration thickness are also presented.