Sample records for mm borax ph

  1. Influence of adding borax and modifying pH on effectiveness of food attractants for melon fly (Diptera: Tephritidae).

    PubMed

    Duyck, P F; Rousse, P; Ryckewaert, P; Fabre, F; Quilici, S

    2004-06-01

    The melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), is the most damaging pest of cucurbits in Reunion Island. The influence of adding borax and modifying pH on the effectiveness of different food attractants for both sexes of the melon fly is analyzed by a release-recapture method in field cages. Adding borax to protein hydrolysates Nulure and Buminal strongly reduced their attractiveness for B. cucurbitae. Acidification of 5% Buminal solution (from pH 6 to pH 3) doubled its attractiveness for melon fly. Conversely, Torula yeast at pH 10.5 was significantly more attractive than the standard Torula yeast at pH 9 (28% of captured flies compared with 17%). However, a further pH increase of the yeast solution does not improve its attractiveness. The results are discussed in relation to other studies on pH modification of various baits for Tephritidae. PMID:15279302

  2. James Hartway, MM, PhD Distinguished Professor,

    E-print Network

    Cinabro, David

    System at the historic Moscow Art Theatre School. Chris Collins, MM Associate Professor of Music Academy of Dramatic Art and Bailar Tanzhaus in Munich. Melvin Rosas, MFA Professor, Drawing An important, imagination and conceptual value. Marion Jackson, PhD Professor, Art History Has an extraordinary record

  3. Molecular Structure of Borax

    NSDL National Science Digital Library

    2003-03-27

    Borax was discovered 4000 years ago. It was first brought to Europe from Kashmir and Tibet. It is deposited by the evaporation of alkaline lakes, and today is mined in California, Nevada, and Tibet. The hydrated mineral is colorless and becomes chalky white during dehydration. It is water soluble, has a sweet alkaline taste, and is brittle. Borax has no toxic fumes; it is environmentally safe and should not be ingested. This chemical is an important source of boron containing compounds such as tincalconite and kernite, and is industrially important in the manufacturing of ceramics, paint, glass, and coated paper. It is also utilized as a disinfectant, insect repellent, water softener, and a detergent. The most common detergent brand is 20 Mule Team Borax.

  4. In vivo Actin Polymerization Assay in Developed Dictyostelium cells 2X Actin Buffer (40 mM KPO4, 20 mM PIPES, 10 mM EGTA, 4 mM MgCl2, pH

    E-print Network

    Robinson, Douglas N.

    SO4, 200 µM CaCl2, pH 6.5) PM Buffer (10 mM Phosphate Buffer, 2 mM MgSO4). Prepare from a stock of 10X Phosphate buffer, pH 6.3) Assay Buffer 1X Actin Buffer C/2 = mL 2X Actin Buffer 3.7 % Formaldehyde C/10 = mIn vivo Actin Polymerization Assay in Developed Dictyostelium cells Solutions: 2X Actin Buffer (40

  5. Solubility and Leaching of Boron from Borax and Colemanite in Flooded Acidic Soils

    Microsoft Academic Search

    M. Saleem; Y. M. Khanif; Y. M. Fauziah Ishak; A. W. Samsuri

    2011-01-01

    Boron (B) is a micronutrient essential for adequate plant growth. Borax (Na2B4O7·10H2O) and colemanite (Ca2B6O11·5H2O) are common B fertilizer materials, the former being widely used worldwide. Boron is completely water soluble and subjected to leaching. In this study, the dissolution kinetics of both borax and colemanite in deionized water and at pH 3.8, 5.2, 6.5, and 8.2 were determined. Soils

  6. Assessment of boric acid and borax using the IEHR evaluative process for assessing human developmental and reproductive toxicity of agents

    SciTech Connect

    Moore, J.A.

    1995-03-01

    This document presents an evaluation of the reproductive and developmental effects of boric acid, H3BO3 (CAS Registry No. 10043-35-3) and disodium tetraborate decahydrate or borax, Na2B4O2O(CAS Registry No. 1303-96-4). The element, boron, does not exist naturally. In dilute aqueous solution and at physiological pH (7.4), the predominant species in undissociated boric acid (greater than 98%), irrespective of whether the initial material was boric acid of borax. Therefore, it is both useful and correct to compare exposures and dosages to boric acid and borax in terms of `boron equivalents`, since both materials form equivalent species in dilute aqueous solution with similar systemic effects. In order to be clear in this document, the term `boron` will refer to `boron equivalents` or percent boron in boric acid and borax.

  7. Dry borax applicator operator's manual.

    SciTech Connect

    Karsky, Richard, J.

    1999-01-01

    Annosum root rot affects conifers throughout the Northern Hemisphere, infecting their roots and eventually killing the trees. The fungus Heterobasidion annosum causes annosum root rot. The fungus colonizes readily on freshly cut stumps. Partially cut stands have a high risk of infestation because the fungus can colonize on each of the stumps and potentially infect the neighboring trees. Wind and rain carry the annosum spores. Spores that land on freshly cut stumps grow down the stump's root system where they can infect living trees through root grafts or root contacts. Once annosum becomes established, it can remain active for many years in the Southern United States and for several decades in the north. About 7% of the trees that become infected die. When thinning, stumps can be treated successfully using a competing fungus, Phlebia gigantea, and with ''Tim-Bor'' in liquid formulations. These liquid products are no longer approved in the United States. Only the dry powder form is registered and approved by the EPA. Stumps can be treated with a dry formula of borax, (Sporax), significantly reducing one of the primary routes by which Heterobasidion annosum infects a stand of trees. Sporax is used by the USDA Forest Service to control annosum root rot. Sporax is now applied by hand, but once the felled trees are skidded it becomes very hard to locate the stumps. A stump applicator will reduce error, labor costs, and hazards to workers.

  8. [Control of the Pharaoh's ant with borax bait formulations].

    PubMed

    Klunker, R; Scheurer, S; Neumann, T

    1990-12-01

    Results are given for the experimental control of Pharaoh ants, Monomorium pharaonis L., with persistent borax baits in the laboratory and the field. DYBH-bait formulations with about 17 per cent borax are very attractive and have a good effectivity. In 5 different objects infested with this ant eradication was proved to be possible with this experimental formulations. The progress of eradication depends essentially on the good organisational preparation of control measures. PMID:2095049

  9. Assessment of boric acid and borax using the IEHR evaluative process for assessing human developmental and reproductive toxicity of agents

    Microsoft Academic Search

    1995-01-01

    This document presents an evaluation of the reproductive and developmental effects of boric acid, H3BO3 (CAS Registry No. 10043-35-3) and disodium tetraborate decahydrate or borax, Na2B4O2O(CAS Registry No. 1303-96-4). The element, boron, does not exist naturally. In dilute aqueous solution and at physiological pH (7.4), the predominant species in undissociated boric acid (greater than 98%), irrespective of whether the initial

  10. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Boric acid and its salts, borax (sodium borate decahydrate...Tolerances § 180.1121 Boric acid and its salts, borax (sodium borate decahydrate...pesticidal chemical boric acid and its salts, borax (sodium borate...

  11. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Boric acid and its salts, borax (sodium borate decahydrate...Tolerances § 180.1121 Boric acid and its salts, borax (sodium borate decahydrate...pesticidal chemical boric acid and its salts, borax (sodium borate...

  12. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Boric acid and its salts, borax (sodium borate decahydrate...Tolerances § 180.1121 Boric acid and its salts, borax (sodium borate decahydrate...pesticidal chemical boric acid and its salts, borax (sodium borate...

  13. 40 CFR 180.1121 - Boric acid and its salts, borax (sodium borate decahydrate), disodium octaborate tetrahydrate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Boric acid and its salts, borax (sodium borate decahydrate...Tolerances § 180.1121 Boric acid and its salts, borax (sodium borate decahydrate...pesticidal chemical boric acid and its salts, borax (sodium borate...

  14. Seizure disorders and anemia associated with chronic borax intoxication

    PubMed Central

    Gordon, A. S.; Prichard, J. S.; Freedman, M. H.

    1973-01-01

    During the course of investigation of two infants with seizure disorders it was discovered that both had been given large amounts of a preparation of borax and honey which resulted in chronic borate intoxication. In one child a profound anemia developed as well. The symptoms of chronic borate intoxication are different from those of the acute poisoning with which we are more familiar. The borax and honey preparations are highly dangerous and should no longer be manufactured or distributed for sale. ImagesFIG. 1FIG. 2 PMID:4691106

  15. Laboratory measurements of the W band (3.2 mm) properties of phosphine (PH3) and ammonia (NH3) under simulated conditions for the outer planets

    NASA Astrophysics Data System (ADS)

    Mohammed, Priscilla N.; Steffes, Paul G.

    2004-07-01

    A model, based on the Van Vleck-Weisskopf line shape, was developed for the centimeter-wavelength opacity of PH3, which provides an order of magnitude improvement over previous models [Hoffman et al., 2001]. New laboratory measurements indicate that the model is also accurate at 94 GHz (3.2 mm) under conditions for the outer planets. Measurements of the opacity and refractivity of PH3 in a hydrogen/helium (H2/He) atmosphere were conducted at 94 GHz (3.2 mm) at pressures of 0.5 and 2 bars and at temperatures of 293 K and 213 K. Additionally, new high-precision laboratory measurements of the opacity and refractivity of NH3 in an H2/He atmosphere were conducted at the same frequency at pressures from 0.5 to 2 bars and at temperatures of 204 K, 211 K, and 290 K. Results show that existing models, which predict NH3 opacity in an H2/He environment, understate the absorption due to the pressure broadened rotational lines. A new model is proposed for use at 94 GHz (3.2 mm) which uses a Ben-Reuven line shape [Ben-Reuven, 1966] for the inversion lines and a Kinetic line shape [Gross, 1955] for the rotational lines. Results of measurements of both PH3 and NH3 can be used to better interpret maps of Saturn's emission at this wavelength and can potentially be used to deduce spatial variations in the abundances of both gases in the atmosphere of Saturn.

  16. Photonic crystal borax competitive binding carbohydrate sensing motif†

    PubMed Central

    Cui, Qingzhou; Muscatello, Michelle M. Ward; Asher, Sanford A.

    2009-01-01

    We developed a photonic crystal sensing method for diol containing species such as carbohydrates based on a poly(vinyl alcohol) (PVA) hydrogel containing an embedded crystalline colloidal array (CCA). The polymerized CCA (PCCA) diffracts visible light. We show that in the presence of borax the diffraction wavelength shifts as the concentration of glucose changes. The diffraction shifts result from the competitive binding of glucose to borate, which reduces the concentration of borate bound to the PVA diols. PMID:19381378

  17. Effect of borax on immune cell proliferation and sister chromatid exchange in human chromosomes

    PubMed Central

    Pongsavee, Malinee

    2009-01-01

    Background Borax is used as a food additive. It becomes toxic when accumulated in the body. It causes vomiting, fatigue and renal failure. Methods The heparinized blood samples from 40 healthy men were studied for the impact of borax toxicity on immune cell proliferation (lymphocyte proliferation) and sister chromatid exchange in human chromosomes. The MTT assay and Sister Chromatid Exchange (SCE) technic were used in this experiment with the borax concentrations of 0.1, 0.15, 0.2, 0.3 and 0.6 mg/ml. Results It showed that the immune cell proliferation (lymphocyte proliferation) was decreased when the concentrations of borax increased. The borax concentration of 0.6 mg/ml had the most effectiveness to the lymphocyte proliferation and had the highest cytotoxicity index (CI). The borax concentrations of 0.15, 0.2, 0.3 and 0.6 mg/ml significantly induced sister chromatid exchange in human chromosomes (P < 0.05). Conclusion Borax had effects on immune cell proliferation (lymphocyte proliferation) and induced sister chromatid exchange in human chromosomes. Toxicity of borax may lead to cellular toxicity and genetic defect in human. PMID:19878537

  18. Corrosion resistance of inconel 690 to borax, boric acid, and boron nitride at 1100°C

    Microsoft Academic Search

    Imrich

    2010-01-01

    Significant general and localized corrosion was observed on Inconel 690 coupons following exposure to borax, boric acid and boron nitride at 1100°C. Severe localized attack at and below the melt line was observed on coupons exposed to borax. An intergranular attack at and below the melt line was observed on coupons exposed to borax. An intergranular attack (IGA) of the

  19. Obtaining of Boron as an Alternative Fuel from Borax with Various Methods

    Microsoft Academic Search

    N. ?en; C. Demir; A. Demirbas; Y. Kar

    2009-01-01

    This study examined how to obtain elemental boron from borax. For this purpose, first boric acid (H3BO3) was obtained from borax decahydrate with using HCl and H2SO4. The boric was then converted to boron oxide using a dehydration process. It has been studied to reduce the boric acid and the boron oxide into elemental boron with using the elemental magnesium

  20. The relationship of blood- and urine-boron to boron exposure in borax-workers and usefulness of urine-boron as an exposure marker.

    PubMed Central

    Culver, B D; Shen, P T; Taylor, T H; Lee-Feldstein, A; Anton-Culver, H; Strong, P L

    1994-01-01

    Daily dietary-boron intake and on-the-job inspired boron were compared with blood- and urine-boron concentrations in workers engaged in packaging and shipping borax. Fourteen workers handling borax at jobs of low, medium, and high dust exposures were sampled throughout full shifts for 5 consecutive days each. Airborne borax concentrations ranged from means of 3.3 mg/m3 to 18 mg/m3, measured gravimetrically. End-of-shift mean blood-boron concentrations ranged from 0.11 to 0.26 microgram/g; end-of-shift mean urine concentrations ranged from 3.16 to 10.72 micrograms/mg creatinine. Creatinine measures were used to adjust for differences in urine-specific gravity such that 1 ml of urine contains approximately 1 mg creatinine. There was no progressive increase in end-of-shift blood- or urine-boron concentrations across the days of the week. Urine testing done at the end of the work shift gave a somewhat better estimate of borate exposure than did blood testing, was sampled more easily, and was analytically less difficult to perform. Personal air samplers of two types were used: one, the 37-mm closed-face, two-piece cassette to estimate total dust and the other, the Institute of Occupational Medicine (IOM) sampler to estimate inspirable particulate mass. Under the conditions of this study, the IOM air sampler more nearly estimated human exposure as measured by blood- and urine-boron levels than did the sampler that measured total dust.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7889874

  1. A Human Health Risk Assessment of Boron (Boric Acid and Borax) in Drinking Water

    Microsoft Academic Search

    F. Jay Murray

    1995-01-01

    A human health risk assessment was conducted to derive an appropriate safe exposure level in drinking water of inorganic boron-containing compounds (boric acid and borax). Several regulatory agencies have set or plan to set drinking water guidelines or standards for boron (B). Recent publication of reproductive and developmental toxicity studies by the National Toxicology Program prompted this risk assessment, along

  2. Association of reversible alopecia with occupational topical exposure to common borax-containing solutions

    Microsoft Academic Search

    William S. Beckett; Roger Oskvig; Mary Ellen Gaynor; Mark H. Goldgeier

    2001-01-01

    Boron is widely used in industrial materials, most frequently as the salt borax. Systemic exposure (eg, ingestion) to boron in boric acid been associated with reversible toxic alopecia among other manifestations. There is scant clinical literature on alopecia caused by topical exposure to boron. We observed a series of 3 patients in 2 workplaces who suffered reversible alopecia from cutaneous

  3. Sorption of boric acid and borax by activated carbon impregnated with various compounds

    Microsoft Academic Search

    Lj. V. Rajakovi?; M. Dj. Risti?

    1996-01-01

    The separation of boron compounds, boric acid and borax from aqueous solution by activated carbon before and after impregnation with various compounds was studied. A series of activated carbons was prepared from coconut shell impregnated with calcium and barium chlorides, citric and tartaric acids. The examined processes were performed in batch and continuous systems under equilibrium and dynamic conditions. Impregnation

  4. Dispersion of borax in plastic is excellent fire-retardant heat insulator

    NASA Technical Reports Server (NTRS)

    Evans, H.; Hughes, J.; Schmitz, F.

    1967-01-01

    A mix of borax powder and a chlorinated anhydrous polyester resin yields a plastic composition that is fire-retardant, yields a minimum of toxic gases when heated, and exhibits high thermal insulating properties. This composition can be used as a coating or can be converted into laminated or cast shapes.

  5. Corrosion resistance of inconel 690 to borax, boric acid, and boron nitride at 1100{degrees}C

    SciTech Connect

    Imrich, K.J.

    1996-12-12

    Significant general and localized corrosion was observed on Inconel 690 coupons following exposure to borax, boric acid and boron nitride at 1100{degrees}C. Severe localized attack at and below the melt line was observed on coupons exposed to borax. An intergranular attack at and below the melt line was observed on coupons exposed to borax. An intergranular attack (IGA) of the Inconel 690 was also observed. Severe internal void formation and IGA (30 mils penetration after 3 days) was observed in the coupon exposed to boric acid. Both borax and boric acid remove the protective chromium oxide; however, this layer can be reestablished by heating the Inconel 690 to 975 {degrees}C in air for several hours. Inconel 690 in direct contact with boron nitride resulted in the formation of a thick chromium borate layer, a general corrosion rate of 50 to 90 mils per year, and internal void formation of 1 mil per day.

  6. Borax mediated layer-by-layer self-assembly of neutral poly(vinyl alcohol) and chitosan.

    PubMed

    Manna, Uttam; Patil, Satish

    2009-07-01

    We report a multilayer film of poly(vinyl alcohol) (PVA)-borate complex and chitosan by using a layer-by-layer approach. PVA is an uncharged polymer, but hydroxyl functional groups of PVA can be cross-linked by using borax as a cross-linking agent. As a result electrostatic charges and intra- and interchain cross-links are introduced in the PVA chain and provide physically cross-linked networks. The PVA-borate was then deposited on a flat substrate as well as on colloidal particles with chitosan as an oppositely charged polyelectrolyte. Quartz crystal microbalance, scanning electron microscopy, and atomic force microscopy were used to follow the growth of thin film on flat substrate. Analogous experiments were performed on melamine formaldehyde colloidal particles (3-3.5 microm) to quantify the process for the preparation of hollow microcapsules. Removal of the core in 0.1 N HCl results in hollow microcapsules. Characterization of microcapsules by transmission electron microscopy revealed formation of stable microcapsules. Further, self-assembly of PVA-borate/chitosan was loaded with the anticancer drug doxorubicin, and release rates were determined at different pH values to highlight the drug delivery potential of this system. PMID:19530685

  7. In vivo percutaneous absorption of boron as boric acid, borax, and disodium octaborate tetrahydrate in humans

    Microsoft Academic Search

    Ronald C. Wester; Xiaoying Hui; Howard I. Maibach; Kathleen Bell; Michael J. Schell; D. Jack Northington; Philip Strong; B. Dwight Culver

    1998-01-01

    Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment\\u000a of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included\\u000a inductively coupled plasma-mass spectrometry, which now allows quantitation of percutaneous absorption of10B in10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological

  8. Epoxy-borax-coal tar composition for a radiation protective, burn resistant drum liner and centrifugal casting method

    DOEpatents

    Taylor, Robert S. (Livermore, CA); Boyer, Norman W. (Livermore, CA)

    1980-01-01

    A boron containing burn resistant, low level radiation protection material useful, for example, as a liner for radioactive waste disposal and storage, a component for neutron absorber, and a shield for a neutron source. The material is basically composed of Borax in the range of 25-50%, coal tar in the range of 25-37.5%, with the remainder being an epoxy resin mix. A preferred composition is 50% Borax, 25% coal tar and 25% epoxy resin. The material is not susceptible to burning and is about 1/5 the cost of existing radiation protection material utilized in similar applications.

  9. Precipitation method for barium metaborate (BaB2O4) synthesis from borax solution

    NASA Astrophysics Data System (ADS)

    Ak?ener, Eymen; Figen, Aysel Kantürk; Pi?kin, Sabriye

    2013-12-01

    In this study, barium metaborate (BaB2O4, BMB) synthesis from the borax solution was carried out. BMB currently is used in production of ceramic glazes, luminophors, oxide cathodes as well as additives to pigments for aqueous emulsion paints and also ?-BaB2O4 single crystals are the best candidate for fabrication of solid-state UV lasers operating at a wavelength of 200 nm due to excellent nonlinear optical properties. In the present study, synthesis was carried out from the borax solution (Na2B4O7?10H2O, BDH) and barium chloride (BaCI2?2H2O, Ba) in the glass-batch reactor with stirring. The effect of, times (5-15 min), molar ratio [stoich.ration (1.0:2.0), 1.25:2.0, 1.5:2.0, 2.5:2:0, 3.0:2.0, 3.5:2.0,4.0:2.0, 5.0:2.0] and also crystallization time (2-6 hour) on the BMB yield (%) was investigated at 80 °C reaction temperature. It is found that, BMB precipitation synthesis with 90 % yield can be performed from 0.50 molar ration (BDH:Ba), under 80 °C, 15 minute, and 6 hours crystallization time. The structural properties of BMB powders were characterized by using XRD, FT-IR and DTA-TG instrumental analysis technique.

  10. The effects of dietary boric acid and borax supplementation on lipid peroxidation, antioxidant activity, and DNA damage in rats

    Microsoft Academic Search

    Sinan Ince; Ismail Kucukkurt; Ibrahim Hakki Cigerci; A. Fatih Fidan; Abdullah Eryavuz

    2010-01-01

    The aims of this study were to clarify the effects of high dietary supplementation with boric acid and borax, called boron (B) compounds, on lipid peroxidation (LPO), antioxidant activity, some vitamin levels, and DNA damage in rats. Thirty Sprague Dawley male rats were divided into three equal groups: the animals in the first group (control) were fed with a standard

  11. ASSESSMENT OF BORIC ACID AND BORAX USING THE IEHR EVALUATIVE PROCESS FOR ASSESSING HUMAN DEVELOPMENT AND REPRODUCTIVE TOXICITY OF AGENTS

    EPA Science Inventory

    This document presents an evaluation of the reproductive and developmental effects of boric acid, H3803 (CAS Registry No. 10043-35-3) and disodium tetraborate decehydrate or borax, Na2B4O2O(CAS Registry No. 1303-96-4). he element, boron, does not exist naturally. oron always exis...

  12. Photonic crystal borax competitive binding carbohydrate sensing motif Qingzhou Cui, Michelle M. Ward Muscatello and Sanford A. Asher*

    E-print Network

    Asher, Sanford A.

    Photonic crystal borax competitive binding carbohydrate sensing motif Qingzhou Cui, Michelle M crystal sensing method for diol containing species such as carbohydrates based on a poly(vinyl alcohol- hydrates.8 Determination of carbohydrates is important in applications such as controlling glycemia

  13. Some physical, biological, mechanical, and fire properties of wood polymer composite (WPC) pretreated with boric acid and borax mixture

    Microsoft Academic Search

    Ergun Baysal; Mustafa Kemal Yalinkilic; Mustafa Altinok; Abdullah Sonmez; Hüseyin Peker; Mehmet Colak

    2007-01-01

    Wood polymer composite (WPC) was obtained by vinyl monomers such as styrene (ST), methylmethacrylate (MMA), and their mixture (50:50; volume:volume) of treated sapwood of Scots pine (Pinus sylvestris L.). Boric acid (BA) and borax (BX) mixture was impregnated into wood at 1% concentration prior to monomer treatment. Wood polymer composite with and without BA and BX mixture pretreatment was evaluated

  14. In vitro percutaneous absorption of boron as boric acid, borax, and disodium octaborate tetrahydrate in human skin

    Microsoft Academic Search

    Ronald C. Wester; Tracy Hartway; Howard I. Maibach; Michael J. Schell; D. Jack Northington; B. Dwight Culver; Philip L. Strong

    1998-01-01

    Literature from the first half of this century reports concern for toxicity from topical use of boric acid, but assessment\\u000a of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included\\u000a inductively coupled plasmamass spectrometry which now allows quantitation of percutaneous absorption of10B in10B-enriched boric acid, borax and disodium octaborate tetrahydrate (DOT) in biological

  15. Mysterious M&M's

    NSDL National Science Digital Library

    James H. Kessler

    2007-01-01

    Learners place an M&M candy in water and observe what happens. The sugar-and-color coating dissolves and spreads out in a circular pattern around the M&M. This introductory activity provides a basis for learners to ask questions and to learn more about dissolving, identifying and controlling variables, and designing a fair test.

  16. 7mm Observations toward Young Massive Stars

    NASA Astrophysics Data System (ADS)

    Hofner, P.; Araya, E.; Linz, H.; Kurtz, S.; Cesaroni, R.; Molinari, S.

    2004-12-01

    We present preliminary result of a VLA 7 mm survey toward 14 regions of massive star formation which are in an evolutionary phase prior to that of ultracompact HII regions. The observations were obtained using bright methanol masers as cross calibration sources. Using additional interferometric data at cm and mm wavelengths we compile the radio SEDs for the sources and discuss possible emission mechanisms responsible for the 7 mm emission, as well as the relation to the 44 GHz methanol masers. This research was partially supported by NSF grant AST-0098524 and grant Nr.CC4966 from the Research Corporation (PH).

  17. Mg- and K-bearing borates and associated evaporites at Eagle Borax spring, Death Valley, California: A spectroscopic exploration

    USGS Publications Warehouse

    Crowley, J.K.

    1996-01-01

    Efflorescent crusts at the Eagle Borax spring in Death Valley, California, contain an array of rare Mg and K borate minerals, several of which are only known from one or two other localities. The Mg- and/or K-bearing borates include aristarainite, hydroboracite, kaliborite, mcallisterite, pinnoite, rivadavite, and santite. Ulexite and probertite also occur in the area, although their distribution is different from that of the Mg and K borates. Other evaporite minerals in the spring vicinity include halite, thenardite, eugsterite, gypsum-anhydrite, hexahydrite, and bloedite. Whereas the first five of these minerals are found throughout Death Valley, the last two Mg sulfates are more restricted in occurrence and are indicative of Mg-enriched ground water. Mineral associations observed at the Eagle Borax spring, and at many other borate deposits worldwide, can be explained by the chemical fractionation of borate-precipitating waters during the course of evaporative concentration. The Mg sulfate and Mg borate minerals in the Eagle Borax efflorescent crusts point to the fractionation of Ca by the operation of a chemical divide involving Ca carbonate and Na-Ca borate precipitation in the subsurface sediments. At many other borate mining localities, the occurrence of ulexite in both Na borate (borax-kernite) and Ca borate (ulexite-colemanite) deposits similarly reflects ulexite's coprecipitation with Ca carbonate at an early concentration stage. Such ulexite may perhaps be converted to colemanite by later reaction with the coexisting Ca carbonate - the latter providing the additional Ca2+ ions needed for the conversion. Mg and Ca-Mg borates are the expected late-stage concentration products of waters forming ulexite-colemanite deposits and are therefore most likely to occur in the marginal zones or nearby mud facies of ulexite-colemanite orebodies. Under some circumstances, Mg and Ca-Mg borates might provide a useful prospecting guide for ulexite-colemanite deposits, although the high solubility of Mg borate minerals may prevent their formation in lacustrine settings and certainly inhibits their geologic preservation. The occurrence of Mg borates in borax-kernite deposits is also related to fractionation processes and points to the operation of an Mg borate chemical divide, characterized by Mg borate precipitation ahead of Mg carbonate. All of these considerations imply that Mg is a significant chemical component of many borate-depositing ground waters, even though Mg borate minerals may not be strongly evident in borate orebodies. The Eagle Borax spring borates and other evaporite minerals were studied using spectroscopic and X-ray powder diffraction methods, which were found to be highly complementary. Spectral reflectance measurements provide a sensitive means for detecting borates present in mixtures with other evaporites and can be used to screen samples rapidly for X-ray diffraction analysis. The apparently limited occurrence of Mg and K borate minerals compared to Ca and Na borates may stem partly from the inefficiency of X-ray diffraction methods for delineating the mineralogy of large and complex deposits. Spectral reflectance measurements can be made in the laboratory, in the field, on the mine face, and even remotely. Reflectance data should have an important role in studies of existing deposit mineralogy and related chemical fractionation processes, and perhaps in the discovery of new borate mineral resources.

  18. Precipitation method for barium metaborate (BaB{sub 2}O{sub 4}) synthesis from borax solution

    SciTech Connect

    Ak?ener, Eymen; Figen, Aysel Kantürk; Pi?kin, Sabriye [Yildiz Technical University, Chem. Eng. Dept., Davutpasa Campus, 34210, Istanbul (Turkey)

    2013-12-16

    In this study, barium metaborate (BaB{sub 2}O{sub 4}, BMB) synthesis from the borax solution was carried out. BMB currently is used in production of ceramic glazes, luminophors, oxide cathodes as well as additives to pigments for aqueous emulsion paints and also ??BaB{sub 2}O{sub 4} single crystals are the best candidate for fabrication of solid-state UV lasers operating at a wavelength of 200 nm due to excellent nonlinear optical properties. In the present study, synthesis was carried out from the borax solution (Na{sub 2}B{sub 4}O{sub 7?}10H{sub 2}O, BDH) and barium chloride (BaCI{sub 2?}2H{sub 2}O, Ba) in the glass-batch reactor with stirring. The effect of, times (5-15 min), molar ratio [stoich.ration (1.0:2.0), 1.25:2.0, 1.5:2.0, 2.5:2:0, 3.0:2.0, 3.5:2.0,4.0:2.0, 5.0:2.0] and also crystallization time (2-6 hour) on the BMB yield (%) was investigated at 80 °C reaction temperature. It is found that, BMB precipitation synthesis with 90 % yield can be performed from 0.50 molar ration (BDH:Ba), under 80 °C, 15 minute, and 6 hours crystallization time. The structural properties of BMB powders were characterized by using XRD, FT-IR and DTA-TG instrumental analysis technique.

  19. Accidental mold\\/termite testing of high density fiberboard (HDF) treated with boric acid, borax and N'-N-naphthoylhydroxylamine (NHA)

    Microsoft Academic Search

    S. Nami Kartal; Harold S. Burdsall; Frederick Green Ill

    High density fibreboard (HDF) was made from beech and pine furnish (50:50) and treated with boric acid (0.1-3%), borax (0.1-3%) or N'-N-(1,8-naphthalyl) hydroxylamine (NHA) (0.1-1%) prior to gluing with urea formaldehyde (UF) resin in order to determine resistance to Eastern subterranean termites ( Reticulitermes flavipes Kollar), the most economically important termite species in North America. HDF and southern yellow pine

  20. Primeval galaxies in the sub-mm and mm

    NASA Technical Reports Server (NTRS)

    Bond, J. Richard; Myers, Steven T.

    1993-01-01

    Although the results of COBE's FIRAS experiment 1 constrain the deviation in energy from the CMB blackbody in the 500-5000 micron range to be delta E/E, sub cmb less than 0.005, primeval galaxies can still lead to a brilliant sub-mm sky of non-Gaussian sources that are detectable at 10 inch resolution from planned arrays such as SCUBA on the James Clerk Maxwell Telescope and, quite plausibly, at sub-arcsecond resolution in planned mm and sub-mm interferometers. Here, we apply our hierarchical peaks method to a CDM model to construct sub-mm and mm maps of bursting PG's appropriate for these instruments with minimum contours chosen to correspond to realistic observational parameters for them and which pass the FIRAS limits.

  1. Racing M&M Colors

    NSDL National Science Digital Library

    2012-04-09

    Learners design their own experiment to determine which M&M color dissolves the fastest in water. Learners should have a plan to control variables such as type of plate, amount of water, temperature of water, how and where the M&M's are placed on the plate, etc. Learners perform their experiment, collect data and discuss their results.

  2. Borax: An Ecofriendly and Efficient Catalyst for One-Pot Synthesis of 3,4-Dihydropyrimidine-2(1H)-ones under Solvent-Free Conditions

    Microsoft Academic Search

    Jayashree Nath; Mihir K. Chaudhuri

    2010-01-01

    Borax in the presence of a very small amount of 5 M sulfuric acid efficiently catalyses the three-component condensation of an aldehyde, ?-ketoester, and urea or thiourea to afford the corresponding 3,4-dihydropyrimidin-2(1H)-ones or 3,4-dihydropyrimidin-2(1H)-thiones in good to excellent yields under solvent-free conditions at 80 °C. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yield, short

  3. SUPPORTING INFORMATION METHODS Buffers. Buffer U is 20 mM TrisHCl, 6 mM NaCl, 1.7 mM MgCl2, 5 mM 2-mercaptoethanol (2-ME),

    E-print Network

    Lohman, Timothy M.

    '-GACCAGTCGATCTACTCCGCTCGCGGTGCACGTCCGCAA. Plaque assay for FX174 phage. FX174 plaque assays were performed with E. coli CK11Drep curves were determined for the following E. coli cells: CK11Drep/pIWcI, CK11Drep/pIWcI/pRepO, and CK11M immidazole, 20% (v/v) glycerol, 1 mM EDTA, 5 mM 2-ME, pH 6.6 at 25°C. Storage buffer for all RepD2B protein

  4. a 3.37 mm length b 3.32 mm diameter

    E-print Network

    Marc, Robert E.

    5.2 ml retinal subtense 300 µm/deg retinal arc 51 mm retinal area* 1024 ± 184 mm2 total.3 µl retinal subtense 31 µm/deg retinal arc 4.9 mm retinal area 15.6 mm2 cone:rod ratio 0/deg retinal arc 10.6 mm retinal area 52 mm2 cone:rod ratio mean cone density* mm-2 mean rod

  5. In VivoPercutaneous Absorption of Boric Acid, Borax, and Disodium Octaborate Tetrahydrate in Humans Compared to in VitroAbsorption in Human Skin from Infinite and Finite Doses

    Microsoft Academic Search

    Ronald C. Wester; Xiaoying Hui; Tracy Hartway; Howard I. Maibach; Kathleen Bell; Michael J. Schelly; D. Jack Northington; Philip Strong; B. Dwight Culver

    1998-01-01

    Literature from the first half of this century report concern for toxicity from topical use of boric acid, but assessment of percutaneous absorption has been impaired by lack of analytical sensitivity. Analytical methods in this study included inductively coupled plasma-mass spectrometry which now allows quantitation of percutaneous absorption of10B in10B-enriched boric acid, borax, and disodium octaborate tetrahydrate (DOT) in biological

  6. Functional photoacoustic microscopy of pH

    NASA Astrophysics Data System (ADS)

    Chatni, M. Rameez; Yao, Junjie; Danielli, Amos; Favazza, Christopher P.; Maslov, Konstantin I.; Wang, Lihong V.

    2012-02-01

    pH is a tightly regulated indicator of metabolic activity. In mammalian systems, imbalance of pH regulation may result from or result in serious illness. Even though the regulation system of pH is very robust, tissue pH can be altered in many diseases such as cancer, osteoporosis and diabetes mellitus. Traditional high-resolution optical imaging techniques, such as confocal microscopy, routinely image pH in cells and tissues using pH sensitive fluorescent dyes, which change their fluorescence properties with the surrounding pH. Since strong optical scattering in biological tissue blurs images at greater depths, high-resolution pH imaging is limited to penetration depths of 1mm. Here, we report photoacoustic microscopy (PAM) of commercially available pH-sensitive fluorescent dye in tissue phantoms. Using both opticalresolution photoacoustic microscopy (OR-PAM), and acoustic resolution photoacoustic microscopy (AR-PAM), we explored the possibility of recovering the pH values in tissue phantoms. In this paper, we demonstrate that PAM was capable of recovering pH values up to a depth of 2 mm, greater than possible with other forms of optical microscopy.

  7. Hickey -TT174, casts 21, line 18 to cast 31, line 24 Cruise cast lat(dd.mm.mm) lon(dd.mm.mm) Date/Time (MMDDYYHHMM) Total Scans

    E-print Network

    Hickey, Barbara

    Hickey -TT174, casts 21, line 18 to cast 31, line 24 Cruise cast lat(dd.mm.mm) lon(dd.mm.mm) Date;Hickey -TT174, casts 21, line 18 to cast 31, line 24 Cruise cast lat(dd.mm.mm) lon(dd.mm.mm) Date;Hickey -TT174, casts 21, line 18 to cast 31, line 24 Cruise cast lat(dd.mm.mm) lon(dd.mm.mm) Date

  8. Life test studies on MM-cathodes

    Microsoft Academic Search

    S. J. Feltham; G. Kornfeld; R. Lotthammer; John L. Stevenson

    1990-01-01

    Mixed metal matrix cathodes (MM-cathodes) were optimized and their life behavior was tested in different test vehicles. In two separate life test programs, 57 MM-cathodes with a W\\/Os matrix were investigated in test vehicles (tetrodes) where the cathode environmental was similar to that of a tube. In parallel, a further 100 MM-cathodes in other types of test vehicles were operated

  9. Life test studies on MM-cathodes

    Microsoft Academic Search

    S. J. Feltham; G. Kornfeld; R. Lotthammer; J. L. Stevenson

    1990-01-01

    Mixed metal matrix cathodes (MM-cathodes) were optimized and their life behavior was tested in different test vehicles. In two separate life test programs, 57 MM-cathodes with a W\\/Os matrix were investigated in test vehicle (tetrodes) where the cathode environment was similar to that of a tube. In parallel, a further 100 MM-cathodes in other types of test vehicles were operated

  10. Application of MM wave therapy in radiology

    SciTech Connect

    Avakian, R.S. [Inst. of Radio Physics & Electronics, Ashtarack (Argentina); Gasparyan, L.V. [Republican Medical Centre Armenia, Yerevan (Argentina)

    1995-12-31

    The authors studied the effects of MM wave electromagnetic radiation influence on patients, affected by X-ray radiation during the reparation works after Chernobyl nuclear power plant exposure. They compared results of treatment of two groups of patients: (1) control group patients received only basis therapy; (2) testing group, 10 patients received basis therapy and MM wave influence. The authors used the wide band noise generator `Artsakh - 2` for local irradiation on the acupuncture points. Their data proved that low intensity MM waves have immunocorrective, antioxidant effects, and MM wave therapy is a perspective method for treatment of patients with radiological pathology.

  11. From the nm to the Mm

    Microsoft Academic Search

    I. M. Villa

    2003-01-01

    Tectonic models for the evolution of an orogen start at the Mm scale, and use field work on smaller subunits at the km scale and rocks collected at the m scale. At the mm scale, minerals are identified, analyzed by mass spectrometry, their \\

  12. MM Algorithms for Some Discrete Multivariate Distributions

    PubMed Central

    Zhou, Hua; Lange, Kenneth

    2010-01-01

    The MM (minorization–maximization) principle is a versatile tool for constructing optimization algorithms. Every EM algorithm is an MM algorithm but not vice versa. This article derives MM algorithms for maximum likelihood estimation with discrete multivariate distributions such as the Dirichlet-multinomial and Connor–Mosimann distributions, the Neerchal–Morel distribution, the negative-multinomial distribution, certain distributions on partitions, and zero-truncated and zero-inflated distributions. These MM algorithms increase the likelihood at each iteration and reliably converge to the maximum from well-chosen initial values. Because they involve no matrix inversion, the algorithms are especially pertinent to high-dimensional problems. To illustrate the performance of the MM algorithms, we compare them to Newton’s method on data used to classify handwritten digits. PMID:20877446

  13. pH Protocol

    NSDL National Science Digital Library

    The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

    2005-06-02

    The purpose of this resource is to measure the pH of water. Students use either a pH meter or pH paper to measure the pH. If using the pH meter, the meter needs to be calibrated with buffer solutions that have pH values of 4, 7, and 10.

  14. Building Equations using M&M's.

    ERIC Educational Resources Information Center

    Borlaug, Victoria

    1997-01-01

    Describes an activity using M&M's in an algebra class after instruction in solving equations that actively involves students in identifying the variable, formulating an equation, then solving the equation. (AIM)

  15. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability...4) Progress reports Yes 63.10(d)(5) Periodic and immediate startup, shutdown, and malfunction...

  16. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability...4) Progress reports Yes 63.10(d)(5) Periodic and immediate startup, shutdown, and malfunction...

  17. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability...4) Progress reports Yes 63.10(d)(5) Periodic and immediate startup, shutdown, and malfunction...

  18. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability...4) Progress reports Yes 63.10(d)(5) Periodic and immediate startup, shutdown, and malfunction...

  19. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM, Table 1 Table 1 to Subpart MM of Part 63—General Provisions Applicability...4) Progress reports Yes 63.10(d)(5) Periodic and immediate startup, shutdown, and malfunction...

  20. Deep sub-mm surveys with SCUBA

    E-print Network

    Ian Smail; Rob Ivison; Andrew Blain; Jean-Paul Kneib

    1998-10-19

    We review published deep surveys in the submillimeter (sub-mm) regime from the new Sub-millimetre Common User Bolometer Array (SCUBA) on the 15-m James Clerk Maxwell Telescope (JCMT), Mauna Kea, Hawaii. Summarising the number counts of faint sub-mm sources determined from the different surveys we show that the deepest counts from our completed SCUBA Lens Survey, down to 0.5mJy at 850um fully account for the far-infrared background (FIRB) detected by COBE. We conclude that a population of distant, dust-enshrouded ultraluminous infrared galaxies dominate the FIRB emission around 1mm. We go on to discuss the nature of this population, starting with the identification of their optical counterparts, where we highlight the important role of deep VLA radio observations in this process. Taking advantage of the extensive archival Hubble Space Telescope (HST) observations of our fields, we then investigate the morphological nature of the sub-mm galaxy population and show that a large fraction exhibit disturbed or interacting morphologies. By employing existing broadband photometry, we derive crude redshift limits for a complete sample of faint sub-mm galaxies indicating that the majority lie at z<5, with at most 20% at higher redshifts. We compare these limits to the initial spectroscopic results from various sub-mm samples. Finally we discuss the nature of the sub-mm population, its relationship to other classes of high-redshift galaxies and its future role in our understanding of the formation of massive galaxies.

  1. Lung lamellar bodies maintain an acidic internal pH.

    PubMed

    Chander, A; Johnson, R G; Reicherter, J; Fisher, A B

    1986-05-01

    The internal pH of lung lamellar bodies was investigated with membrane permeable basic amines. Isolated granular pneumocytes and isolated lung lamellar bodies exhibited fluorescence when exposed to 8 microM quinacrine, suggesting accumulation of this dye due to an acidic internal pH. Uptake of [14C]methylamine by isolated lung lamellar bodies was measured to quantitate the intralamellar body pH. In KCl-ATP (10 mM) medium (pH 7.0), the accumulation ratio of methylamine (inside/outside) during 2-min incubation was 8.1 +/- 0.47 (mean +/- S.E., n = 8) indicating an internal pH of 6.1. Lamellar bodies accumulated methylamine almost 30-fold in K+-free mannitol medium indicating an internal pH of 5.6. The pH gradient across the lamellar body membrane decreased when external pH was decreased or when ATP was omitted. The pH gradient was also decreased by the addition of 10 mM NH4Cl, 2 micrograms/ml nigericin, 0.02 mM N,N'-dicyclohexylcarbodiimide, or 1 mM N'-ethylmaleimide. These observations indicate that lamellar bodies maintain an acidic interior (pH 6.1 or below) which is generated by an energy-dependent process. PMID:3700387

  2. Laparoscopic cholecystectomy using 2-mm instruments.

    PubMed

    Uranüs, S; Peng, Z; Kronberger, L; Pfeifer, J; Salehi, B

    1998-10-01

    Today, laparoscopic cholecystectomy is the method of choice for treatment of symptomatic gallbladder disorders. It minimizes effects of the operation that are independent of the gallbladder, such as trauma to the abdominal wall and other soft tissue. The surgical wounds were even smaller when 2-mm trocars were used. Laparoscopic cholecystectomy using 2-mm instruments was performed in a consecutive series of 14 patients with symptomatic gallstones. The procedure was completed in 12 cases, with conversion to open surgery in two cases. Intraoperative cholangiography was always performed. The postoperative course was always uneventful. The cosmetic effect was highly satisfactory. The procedure using 2-mm instruments could be indicated in selected patients with uncomplicated gallstone disease. PMID:9820716

  3. Microeconomics of 300-mm process module control

    NASA Astrophysics Data System (ADS)

    Monahan, Kevin M.; Chatterjee, Arun K.; Falessi, Georges; Levy, Ady; Stoller, Meryl D.

    2001-08-01

    Simple microeconomic models that directly link metrology, yield, and profitability are rare or non-existent. In this work, we validate and apply such a model. Using a small number of input parameters, we explain current yield management practices in 200 mm factories. The model is then used to extrapolate requirements for 300 mm factories, including the impact of simultaneous technology transitions to 130nm lithography and integrated metrology. To support our conclusions, we use examples relevant to factory-wide photo module control.

  4. A New Laboratory for MM-/Sub-MM-Wave Characterization of Cosmic Dust Analogs

    NASA Astrophysics Data System (ADS)

    Birsa, Samuel; Do, Huy; Williams, Frederick; Liu, Lunjun; Schonert, Ryan; Perera, Thushara

    2015-01-01

    Most studies conducted with observatories such as ALMA, SOFIA, PLANCK, and Herschel will benefit from knowledge of (1) the predominant cosmic dust species in various environments, in terms of composition and structure and (2) mm/sub-mm optical properties of cosmic dusts, including the temperature dependent-emissivity and spectral index. A new laboratory has been established for producing and characterizing (in the mm/sub-mm) various silicate/carbonaceous dust candidates. In particular, the optical measurement setup was custom designed, specifically for laboratory studies of dusts, using techniques borrowed from observational cosmology. It features novel designs for a compact Fourier Transform Spectrometer (FTS) and a cold sample holder/exchanger. Construction of this apparatus is now complete; we are currently testing the system. Here, we present the mm/sub-mm measurement scheme and highlight its innovative and aspects.

  5. pH

    NSDL National Science Digital Library

    This lab activity is designed to teach students how to test for pH and understand its relationship to them and their environment. They will learn what pH is, draw and label a pH scale, measure the pH of various items, and explain why it's important to understand pH, for example, the danger presented by substances having very high or low pH.

  6. M&M's in Different Temperatures

    NSDL National Science Digital Library

    James H. Kessler

    2007-01-01

    Learners design their own experiment to investigate whether the temperature of the surrounding water affects the rate at which the colored coating dissolves from an M&M. When they conduct their experiment, they find that the color dissolves faster in hot water than in cold.

  7. MM-122: High speed civil transport

    NASA Technical Reports Server (NTRS)

    Demarest, Bill; Anders, Kurt; Manchec, John; Yang, Eric; Overgaard, Dan; Kalkwarf, Mike

    1992-01-01

    The rapidly expanding Pacific Rim market along with other growing markets indicates that the future market potential for a high speed civil transport is great indeed. The MM-122 is the answer to the international market desire for a state of the art, long range, high speed civil transport. It will carry 250 passengers a distance of 5200 nm at over twice the speed of sound. The MM-122 is designed to incorporate the latest technologies in the areas of control systems, propulsions, aerodynamics, and materials. The MM-122 will accomplish these goals using the following design parameters. First, a double delta wing planform with highly swept canards and an appropriately area ruled fuselage will be incorporated to accomplish desired aerodynamic characteristics. Propulsion will be provided by four low bypass variable cycle turbofan engines. A quad-redundant fly-by-wire flight control system will be incorporated to provide appropriate static stability and level 1 handling qualities. Finally, the latest in conventional metallic and modern composite materials will be used to provide desired weight and performance characteristics. The MM-122 incorporates the latest in technology and cost minimization techniques to provide a viable solution to this future market potential.

  8. M&M's in Different Sugar Solutions

    NSDL National Science Digital Library

    James H. Kessler

    2007-01-01

    In this activity, learners investigate whether having sugar already dissolved in water affects the speed of dissolving and the movement of sugar and color through the water. Learners design their own experiment and identify and control variables. This activity is a follow-up to the activity "Racing M&M Colors" (see related resources).

  9. Economic analysis of 450mm wafer migration

    Microsoft Academic Search

    Chen-Fu Chien; J. K. Wang; Tzu-Ching Chang; Wen-Chin Wu

    2007-01-01

    To achieve the required continuous cost reduction driven by Moore's Law, both miniaturization through technology advances and wafer size increase have been employed in order to maintain the growth and profitability of semiconductor industry. Although some technical analyses have been done for 450 mm migration, little research has been done on economic analysis to justify the decisions and thus suggest

  10. Effect of the borax mass and pre-spray medium temperature on droplet size and velocity vector distributions of intermittently sprayed starchy solutions.

    PubMed

    Naz, Muhammad Yasin; Sulaiman, Shaharin Anwar; Ariwahjoedi, Bambang

    2015-02-01

    Spray coating technology has demonstrated great potential in the slow release fertilizers industry. The better understanding of the key spray parameters benefits both the environment and low cost coating processes. The use of starch based materials to coat the slow release fertilizers is a new development. However, the hydraulic spray jet breakup of the non-Newtonian starchy solutions is a complex phenomenon and very little known. The aim of this research was to study the axial and radial distributions of the Sauter Mean Diameter (SMD) and velocity vectors in pulsing spray patterns of native and modified tapioca starch solutions. To meet the objective, high speed imaging and Phase Doppler Anemometry (PDA) techniques were employed to characterize the four compositions of the starch-urea-borax complex namely S0, S1, S2 and S3. The unheated solutions exhibited very high viscosities ranging from 2035 to 3030 cP. No jet breakup was seen at any stage of the nozzle operation at an injection pressure of 1-5 bar. However, at 80 °C temperature and 5 bar pressure, the viscosity was reduced to 455 to 638 cP and dense spray patterns emerged from the nozzle obscuring the PDA signals. The axial size distribution revealed a significant decrease in SMD along the spray centreline. The smallest axial SMD (51 to 79 ?m) was noticed in S0 spray followed by S1, S2 and S3. Unlikely, the radial SMD in S0 spray did not vary significantly at any stage of the spray injection. This trend was attributed to the continuous growth of the surface wave instabilities on the native starch sheet. However, SMD obtained with S1, S2 and S3 varied appreciably along the radial direction. The mean velocity vector profiles followed the non-Gaussian distribution. The constant vector distributions were seen in the near nozzle regions, where the spray was in the phase of development. In far regions, the velocity vectors were poly-dispersed and a series of ups and downs were seen in the respective radial distributions. PMID:25557285

  11. The 90-mm period undulator for SRRC

    Microsoft Academic Search

    D. C. Quimby; S. C. Gottschalk; D. R. Jander; T. E. DeHart; K. E. Robinson; A. S. Valla; J. F. Zumdieck

    1999-01-01

    The U9\\/SRRC undulator has recently been completed by STI Optronics Inc. (STI) for use at the Synchrotron Radiation Research Center (SRRC) in Hsinchu, Taiwan, R.O.C. This 4.5-m long, 90-mm period wedged-pole hybrid undulator builds on several aspects of previous STI designs while including a number of significant enhancements. The magnetics are based on the wedged-pole geometry with additional side magnets.

  12. Population Simulation with M&M's

    NSDL National Science Digital Library

    PBS TeacherSource - Math

    2010-01-01

    This activity involves two simulations with M&M's® to explore population growth and decay. The follow-up activity, Population Simulations with Calculators introduces NOW-NEXT or recursive equations as an accessible way to model this behavior and expand to other population models. Using mathematics and mathematical models, students will learn to build and refine models to help predict how the size of a population will change over time.

  13. Vibrational analysis of 200-mm EPL masks

    NASA Astrophysics Data System (ADS)

    Mikkelson, Andrew R.; Chen, Cheng-Fu; Engelstad, Roxann L.; Lovell, Edward G.

    2001-08-01

    The vibratory response of Electron-beam Projection Lithography (EPL) masks has been characterized for two applications: to support the processes for mask cleaning (e.g., PLASMAX) and to preclude resonance conditions during metrology and inspection. The analysis of a 200-mm SCALPEL mask has been completed using experimental and numerical procedures to determine the dynamic response; the procedures characterized transverse vibrations by identifying the natural frequencies with their respective mode shapes. For mask cleaning applications, dominant modes were superimposed to form a more uniform acceleration field within the grillage area for effective removal of contaminants. In order to assess potential resonance issues, a finite element model was used to simulate the four-pad support, which is currently proposed for the EPL mask standard chuck. The fundamental frequency of the mask in the four-pad support was over 300Hz.

  14. Simulation of Thermal Processes in Metamaterial MM-to-IR Converter for MM-wave Imager

    NASA Astrophysics Data System (ADS)

    Zagubisalo, Peter S.; Paulish, Andrey G.; Kuznetsov, Sergey A.

    2014-03-01

    The main characteristics of MM-wave image detector were simulated by means of accurate numerical modelling of thermophysical processes in a metamaterial MM-to-IR converter. The converter represents a multilayer structure consisting of an ultra thin resonant metamaterial absorber and a perfect emissive layer. The absorber consists of a dielectric self-supporting film that is metallized from both sides. A micro-pattern is fabricated from one side. Resonant absorption of the MM waves induces the converter heating that yields enhancement of IR emission from the emissive layer. IR emission is detected by IR camera. In this contribution an accurate numerical model for simulation of the thermal processes in the converter structure was created by using COMSOL Multiphysics software. The simulation results are in a good agreement with experimental results that validates the model. The simulation shows that the real time operation is provided for the converter thickness less than 3 micrometers and time response can be improved by decreasing of the converter thickness. The energy conversion efficiency of MM waves into IR radiation is over 80%. The converter temperature increase is a linear function of a MM-wave radiation power within three orders of the dynamic range. The blooming effect and ways of its reducing are also discussed. The model allows us to choose the ways of converter structure optimization and improvement of image detector parameters.

  15. 40 Gbit/s silicon modulators fabricated on 200-mm and 300-mm SOI wafers

    NASA Astrophysics Data System (ADS)

    Marris-Morini, Delphine; Baudot, Charles; Fédéli, Jean-Marc; Rasigade, Gilles; Vuillet, Nathalie; Souhaité, Aurélie; Ziebell, Melissa; Rivalin, Pierette; Olivier, Ségolène; Crozat, Paul; Bouville, David; Menezo, Sylvie; Boeuf, Frédéric; Vivien, Laurent

    2014-03-01

    We present 40 Gbit/s optical modulators based on different types of phase shifters (lateral pn, pipin, and interleaved pn junction phase). Those structures were processed both on 200 and 300mm SOI wafers, available in large-scale microelectronic foundries. Both Ring Resonators (RR) and Mach Zehnder (MZ) modulators were fabricated. As an example, MZ modulator based on 0.95 mm long interleaved pn junction phase shifter delivered a high ER of 7.8 dB at 40 Gbit/s with low optical loss of only 4 dB. Ring modulator was also fabricated and characterized at high-speed, exhibiting 40 Gbit/s.

  16. A comparison of 9-inch, 70mm, and 35mm cameras

    NASA Technical Reports Server (NTRS)

    Clegg, R. H.; Scherz, J. P.

    1975-01-01

    Successful aerial photography depends on aerial cameras that provide acceptable photographs within the cost restrictions of the job. For topographic mapping where ultimate accuracy is required, only large-format mapping cameras will suffice. For mapping environmental patterns of vegetation, soils, or water pollution, 9-inch cameras often exceed accuracy and cost requirements, and small formats may be an overall better choice. In choosing the best camera for environmental mapping, relative capabilities and costs must be understood. This study compares resolution, photo interpretation potential, metric accuracy, and cost of 9-inch, 70 mm, and 35 mm cameras for obtaining simultaneous color and color-infrared photography for environmental mapping purposes.

  17. Urban parameterization schemes into MM5 model

    NASA Astrophysics Data System (ADS)

    Dandou, A.; Akylas, E.; Tombrou, M.

    2003-04-01

    In the last few years, several efforts have been made in order to improve the representation of urban surface characteristics in mesoscale models. In general, attempts have been made either to improve the ‘thermal’ part (impact on the heat fluxes) or the ‘dynamical’ part (impact on the wind field and the turbulent kinetic energy). The objective is to improve the quantification of the fluxes associated with heat storage change and to account more explicitly for the integrated effect of urban canopy layer fluxes on the overlaying boundary layer. This modification is very important, since pollutant dispersion is strongly dependent on the structure of the urban boundary layer and on its interactions with the rural boundary layer and the synoptic flow. In the present study, the MM5 model (Penn State/NCAR Mesoscale Model, Anthes et al., 1978) was modified, by considering recent advances in the planetary boundary layer. In particular, the modifications were carried out in two directions; a) the surface stress and fluxes of heat and momentum were parameterized for use of the MM5 model with emphasis laid on unstable conditions. The key quantities in these parameterizations are the PBL height and the convective velocity scale W*. In addition, the Kansas-type functions were modified in order to satisfy the free convection limit which is particularly important in cases with larger roughness lengths; and (b) with respect to the thermal properties of an urban surface, the surface energy balance was modified by taking into account the anthropogenic heat released in urban areas and the urban heat storage term, to account for urban/building mass effect, including hysteresis. These modifications were applied to the high resolution non-local MRF PBL parameterization scheme, based on Troen and Marht. Numerical simulations were carried out for the Greater Athens area. The modifications mentioned above, produce minor changes to the wind field, but they enhance the value of friction velocity up to 25% during strong instability over very rough surfaces and the diffusion coefficients, up to a proportion of 30%, depending on the intensity of the instability. Moreover, they enhance the temperature’s diurnal range. These enhancements affect the pollutants deposition velocity and consequently the pollutants dispersion in the atmosphere.

  18. pH Calculation

    NSDL National Science Digital Library

    Johansson, Stig

    This pair of pH calculation programs serves as an excellent tool for anyone wishing to calculate the pH of a solution containing multiple acids and bases. These programs allow practitioners to predict the pH of simple and complex acid/base solutions and buffers. They may be downloaded free of charge via the website. Users are encouraged to carefully read the guides provided by the author.

  19. Comparative analysis between 5 mm and 7.5 mm collimators in CyberKnife radiosurgery for trigeminal neuralgia

    PubMed Central

    Sudahar, H.; Kurup, P. G. G.; Murali, V.; Velmurugan, J.

    2013-01-01

    Trigeminal neuralgia (TN) is treated in CyberKnife (Accuray Inc, Sunnyvale, USA) with the 5 mm collimator whose dosimetric inaccuracy is higher than the other available collimators. The 7.5 mm collimator which is having less dosimetric uncertainty can be an alternative for 5 mm collimator provided the dose distribution with 7.5 mm collimator is acceptable. Aim of this study is to analyze the role of 7.5 mm collimator in CyberKnife treatment plans of TN. The treatment plans with 5 mm collimators were re-optimized with 7.5 mm collimator and a bi-collimator system (5 mm and 7.5 mm). The treatment plans were compared for target coverage, brainstem doses, and the dose to normal tissues. The target and brainstem doses were comparable. However, the conformity indices were 2.31 ± 0.52, 2.40 ± 0.87 and 2.82 ± 0.51 for 5 mm, bi-collimator (5mm and 7.5 mm), 7.5 mm collimator plans respectively. This shows the level of dose spillage in 7.5 mm collimator plans. The 6 Gy dose volumes in 7.5 mm plans were 1.53 and 1.34 times higher than the 5 mm plan and the bi-collimator plans respectively. The treatment time parameters were lesser for 7.5 mm collimators. Since, the normal tissue dose is pretty high in 7.5 mm collimator plans, the use of it in TN plans can be ruled out though the treatment time is lesser for these 7.5 mm collimator plans. PMID:24049318

  20. Teaching Evolutionary Mechanisms: Genetic Drift and M&M's.

    ERIC Educational Resources Information Center

    Staub, Nancy L.

    2002-01-01

    Describes a classroom activity that teaches the mechanism of genetic drift to undergraduates. Illustrates a number of concepts that are critical in developing evolution literacy by sampling M&M milk chocolate candies. (MM)

  1. The microwave spectrum of the PH2 radical

    Microsoft Academic Search

    Yasuki Endo; Shuji Saito; Eizi Hirota

    1983-01-01

    Three rotational transitions, 110 <-- 101, 220 <-- 211, and 330 <-- 321, of the PH2 radical in the ground vibronic state were observed in the mm-wave region, by using a source-frequency modulation spectrometer with a 1-m-long free space cell. The PH2 radical was generated directly in the cell by glow discharge in a mixture of phosphine and oxygen. Thirty

  2. Manufacturing of the (phi)500-mm F\\/2 ellipsoid mirror

    Microsoft Academic Search

    Xinnan Li; Junhua Pan; Xingtao Liu; Lijun Yuan; Zili Xia

    2000-01-01

    An ellipsoid mirror with (Phi) 500 mm aperture has been successfully manufactured by NAIRC. The parameters of the mirror are as follows: diameter is (Phi) 500 mm, radius of curvature is 1996 mm, conic constant k equals -0.9545, requirements of surface accuracy are (lambda) \\/10 (P-V) and (lambda) \\/40 (RMS), ((lambda) equals 632.8 nm). Based on the surface type, three

  3. Growth of 450 mm diameter semiconductor grade silicon crystals

    Microsoft Academic Search

    Zheng Lu; Steven Kimbel

    2011-01-01

    Research and development of the next generation 450mm semiconductor grade silicon crystal and related technology have been carried out in MEMC following the company’s philosophy to stay one generation ahead on research and development. The first 450mm dislocation free crystal was grown in early 2009 and the first 450mm semiconductor wafer was produced shortly after. General challenges in crystal growth

  4. 382 Mlle J. BRIGANDO ET MM. CHAMP ET CLOSSON. -LES PHOSPHATES LES PHOSPHATES DE CALCIUM DU LAIT

    E-print Network

    Paris-Sud XI, Université de

    rapport -- est égal à 0,58. CaO Le lait titre 22° D. et son pH est ramené à 6,67. p205 Dans le phosphate publié à la Société de Chimie Industrielle, et ci-dessus mentionné. A un lait titrant 28° Dornic.etde pH382 Mlle J. BRIGANDO ET MM. CHAMP ET CLOSSON. -LES PHOSPHATES LES PHOSPHATES DE CALCIUM DU LAIT

  5. Is smaller better? Comparison of 3-mm and 5-mm leaf size for stereotactic radiosurgery: A dosimetric study

    SciTech Connect

    Chern, Shyh-shi [Department of Radiation Oncology, University of Utah School of Medicine, Salt Lake City, Utah (United States)]. E-mail: Richard.Chern@hci.utah.edu; Leavitt, Dennis D. [Department of Radiation Oncology, University of Utah School of Medicine, Salt Lake City, Utah (United States); Jensen, Randy L. [Department of Neurosurgery, University of Utah School of Medicine, Salt Lake City, Utah (United States); Shrieve, Dennis C. [Department of Radiation Oncology, University of Utah School of Medicine, Salt Lake City, Utah (United States)

    2006-11-15

    Purpose: To perform a dosimetric comparison of a minimal 3-mm leaf width multileaf collimator (MLC) and a minimal 5-mm MLC in dynamic conformal arc stereotactic radiosurgery for treatment of intracranial lesions. Methods and Materials: The treatment plans of 23 patients previously treated for intracranial lesions in our institution were redone using the BrainSCAN, version 5.3, stereotactic radiosurgery treatment planning system (BrainLAB). For each case, two dynamic conformal arc plans were generated: one using a minimal 3-mm micro-MLC (BrainLAB, Novalis) and one using a minimal 5-mm MLC (Varian Millennium). All arc parameters were the same in each of the two plans, except for the collimator angle settings. The collimator angle settings were optimized for each arc in each plan. A peritumoral rind structure (1 cm) was created to evaluate normal tissue sparing immediately adjacent to the target volume. Conformity indexes (CIs) were calculated for each plan. The dependence of normal tissue sparing and target conformity on target volume (TV) was determined. Results: The TV was 0.14-36.32 cm{sup 3} (median, 5.90). The CI was 1.22-2.60 (median, 1.51) for the 3-mm micro-MLC and 1.23-2.69 (median, 1.60) for the 5-mm MLC. Despite this small difference, it was a statistically significant increase (p < 0.0001) for the 5-mm MLC compared with the 3-mm micro-MLC. Improved normal tissue sparing was demonstrated using the 3-mm micro-MLC compared with the 5-mm MLC by examining the peritumoral rind volumes (PRVs) receiving 50% (PRV{sub 5}), 80% (PRV{sub 8}), and 90% (PRV{sub 9}) of the prescription dose. The reduction in the PRV{sub 5}, PRV{sub 8}, and PRV{sub 9} for the 3-mm micro-MLC compared with the 5-mm MLC was 13.5%, 12.9%, and 11.5%, respectively. The CI decreased with a larger TV, as did the difference in the CIs between the 3-mm micro-MLC and 5-mm MLC. A reduction in the PRV increased with larger TVs. Conclusion: The 3-mm micro-MLC provided better target conformity and greater normal tissue sparing than the 5-mm MLC in stereotactic radiosurgery using dynamic conformal arcs. These differences were small but consistent in the patients examined. Future research is needed to determine whether this small improvement can yield a clinical impact on patient care.

  6. Course Outline ENG 2MM3 Electrical Circuits & Power

    E-print Network

    Haykin, Simon

    . Reference Book: T. Wildi, Electrical machines, drives and power systems, Prentice Hall, Fifth edition, 2002.ece.mcmaster.ca/~kumar/eng_2mm3 Text Book: S.J. Chapman, Electric Machinery Fundamentals, McGraw Hill, Fourth Edition, 2005Course Outline ENG 2MM3 Electrical Circuits & Power Fall 2011 Instructor: Shiva Kumar Web Page: www

  7. Course Outline: ENGINEER 2MM3 Electrical Circuits & Power

    E-print Network

    Haykin, Simon

    Graw Hill, Fourth Edition, 2005. Reference Book: T. Wildi, Electrical machines, drives and power systems Page: www.ece.mcmaster.ca/~kumars/eng_2mm3 Text Book: S.J. Chapman, Electric Machinery Fundamentals, McCourse Outline: ENGINEER 2MM3 Electrical Circuits & Power Fall 2013 Instructor: Shiva Kumar Web

  8. 1 mm3 resolution breast-dedicated PET system

    Microsoft Academic Search

    Frances W. Y. Lau; Chen Fang; Paul D. Reynolds; Peter D. Olcott; Arne Vandenbroucke; Virginia C. Spanoudaki; Femi Olutade; Mark A. Horowitz; Craig S. Levin

    2008-01-01

    We are developing a 1 mm3 resolution breast-dedicated Positron Emission Tomography (PET) system in an effort to increase the role of PET in earlier stages of breast cancer management. The system consists of two 16 cm × 9 cm × 2 cm detector panels constructed using stacked layers of 8×8 arrays of 1 mm3 LSO scintillation crystals coupled to Position

  9. The pH Game

    NSDL National Science Digital Library

    This learning activity engages students in measurement of pH in water and soil samples, plants and other natural materials. By mixing different substances, they observe how pH changes, and become familiar with the pH of common household products. Through discussion, they learn how pH can be modified in the environment.

  10. pH Scale

    NSDL National Science Digital Library

    Wendy Adams

    2011-01-01

    In this online interactive simulation, learners will test the pH of liquids like coffee, spit, and soap to determine whether each is acidic, basic, or neutral. Learners will visualize the relative number of hydroxide ions and hydronium ions in a solution, and they can switch between logarithmic and linear scales. Learners will also investigate whether changing the volume or diluting with water affects the pH. They can experiment by designing their own liquids! This activity includes an online simulation, sample learning goals, a teacher's guide, and translations in over 30 languages.

  11. ?-Cyclodextrin facilitates simultaneous analysis of six bioactive components in Rhizoma Smilacis Glabrae by capillary zone electrophoresis

    Microsoft Academic Search

    Qing-Feng Zhang; Sze-Chun Li; Wai-Ping Lai; Hon-Yeung Cheung

    2009-01-01

    A cyclodextrin-modified capillary zone electrophoretic method was developed for the separation and determination of trans-resveratrol, astilbin, taxifolin, shikimic acid, syringic acid and ferulic acid in Rhizoma Smilacis Glabrae. A running buffer comprising 20mM borax and 2mM ?-cyclodextrin at pH 9.46 was used. These six components were well separated from each other within 8min at a voltage of 25kV, temperature of

  12. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Default Factors for Petroleum Products and Natural Gas Liquids 1 2...GREENHOUSE GAS REPORTING Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table...MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1...

  13. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Default Factors for Petroleum Products and Natural Gas Liquids 1 2...GREENHOUSE GAS REPORTING Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table...MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1...

  14. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Default Factors for Petroleum Products and Natural Gas Liquids 1 2...GREENHOUSE GAS REPORTING Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table...MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1...

  15. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Default Factors for Petroleum Products and Natural Gas Liquids 1 2...GREENHOUSE GAS REPORTING Suppliers of Petroleum Products Pt. 98, Subpt. MM, Table...MM of Part 98—Default Factors for Petroleum Products and Natural Gas Liquids 1...

  16. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2...Default Factors for Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density...metric tons CO2 /bbl) Ethanol (100%) 0.1267...

  17. pH optrode

    DOEpatents

    Northrup, M. Allen (Berkeley, CA); Langry, Kevin C. (Tracy, CA)

    1993-01-01

    A process is provided for forming a long-lasting, stable, pH-sensitive dye-acrylamide copolymer useful as a pH-sensitive material for use in an optrode or other device sensitive to pH. An optrode may be made by mechanically attaching the copolymer to a sensing device such as an optical fiber.

  18. pH Basics

    ERIC Educational Resources Information Center

    Lunelli, Bruno; Scagnolari, Francesco

    2009-01-01

    The exposition of the pervasive concept of pH, of its foundations and implementation as a meaningful quantitative measurement, in nonspecialist university texts is often not easy to follow because too many of its theoretical and operative underpinnings are neglected. To help the inquiring student we provide a concise introduction to the depth just…

  19. Role of Decorin in Multiple Myeloma (MM) Bone Marrow Microenvironment.

    PubMed

    Nemani, Neeharika; Santo, Loredana; Eda, Homare; Cirstea, Diana; Mishima, Yuko; Patel, Chirayu; O'Donnell, Elizabeth; Yee, Andrew; Raje, Noopur

    2015-03-01

    Decorin is a small, leucine-rich proteoglycan found in the extracellular matrix of various connective tissues with potential effective tumor suppressive properties. Recent data suggest low levels of decorin in multiple myeloma (MM) patients compared to healthy volunteers, as well as in patients with osteolytic bone lesions compared to non-osteolytic lesions. In the present report, we investigated the role of decorin in the MM microenvironment or niche. Our data suggests that decorin is produced by osteoblasts (OBs) but not by MM cells. Furthermore, MM cells decrease OB-induced decorin secretion and this effect is mediated by CCL3. Importantly, neutralizing CCL3 from MM cells restores decorin levels in OBs as does proteasome inhibitors such as carfilzomib. These findings indicate that decorin may indirectly act as an antagonist to MM cell survival and that the interplay between MM and decorin may be an important target to explore in manipulating the tumor niche to inhibit tumorigenesis. © 2014 American Society for Bone and Mineral Research. PMID:25407518

  20. Advanced mm-wave receivers for EW applications

    NASA Astrophysics Data System (ADS)

    Cohen, L.; Irvin, G.; Levy, J.; Meier, P.; Paczkowski, H.

    1986-04-01

    Activity in the mm-wave area has increased dramatically over the past few years. With the near- and long-term threats expected in the EW community, advanced developmental concepts are required to configure state-of-the-art frequency extension receivers that are operationally compatible with existing microwave systems. A new system-concept being developed is the use of computer-controlled receivers that can effectively scan the mm-wave spectrum with a high probability of intercept. Some of these advanced receiver concepts covering the 18 to 40 GHz frequency spectrum are covered, along with specialized mm-wave components critical to system performance.

  1. Effects of different pH conditions on enamel erosion repair by nano fluorapatite pastes.

    PubMed

    Wang, Chengjie; Zhang, Yifei; Wei, Jie; Wei, Shicheng

    2012-09-01

    The effects of different pH conditions on enamel erosion repair by nano fluorapatite (n-FA) pastes were evaluated in this study. Eighteen human dental enamel blocks with artificially-induced erosion were randomly divided into three groups that were coated with n-FA pastes with 3 different pH values (pH < 1, pH = 4.5 and pH = 7.5, respectively) for 15 minutes. SEM, XRD, XPS, Vickers microhardness test and mass measurement were performed for the enamels before and after treatment. A layer of enamel-like fluoride substituted hydroxyapatite was observed on the surface of all the samples. After treatment by n-FA pastes with 3 different pH values (pH < 1, pH = 4.5 and pH = 7.5), the Vickers micro-hardness value was respectively changed to 125.9 HV, 252.1 HV and 304.9 HV from 241.3 HV of the artificial enamel erosion, and mass loss was 0.75 mg/mm2, 0.41 mg/mm2 and 0.30 mg/mm2, respectively. SEM analysis showed that the surface of the enamels treated by n-FA pastes with pH 7.5 and pH 4.5 was smoother than those treated by n-FA pastes with pH < 1. These results suggested that the pH value had significant effects for the repairment of enamel erosion with n-FA pastes. This study demonstrated that the n-FA paste with neutral pH value (7.5) for enamel erosion repair would not only significantly enhance the enamel surface hardness, but also avoid the enamel mass loss and increased surface roughness. PMID:23035475

  2. Building 932, oblique view to northwest, 90 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 932, oblique view to northwest, 90 mm lens. Building 933-935 at extreme left. - Travis Air Force Base, Nuclear Weapons Assembly Plant 5, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  3. Building 1204, oblique view to east, 90 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to east, 90 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  4. Building 904, oblique view to northeast, 210mm lens Travis ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northeast, 210mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  5. Building 904, oblique view to northwest, 135 mm lens ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northwest, 135 mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  6. Building 909, oblique view to southeast, 135 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 909, oblique view to southeast, 135 mm lens. Building 908 at extreme right for context. - Travis Air Force Base, Handling Crew Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  7. Building 904, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  8. Building 1204, oblique view to west, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to west, 135 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  9. Building 931, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  10. Building 931, oblique view to northwest, 210 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to northwest, 210 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  11. Combined quantum and molecular mechanics (QM/MM).

    PubMed

    Friesner, Richard A

    2004-12-01

    We describe the current state of the art of mixed quantum mechanics/molecular mechanics (QM/MM) methodology, with a particular focus on modeling of enzymatic reactions. Over the past decade, the effectiveness of these methods has increased dramatically, based on improved quantum chemical methods, advances in the description of the QM/MM interface, and reductions in the cost/performance of computing hardware. Two examples of pharmaceutically relevant applications, cytochrome P450 and class C ?-lactamase, are presented.: PMID:24981493

  12. Exercise and Pulmonary Hypertension (PH)

    MedlinePLUS

    ... Young Adult Issues Dating and Relationships College and Scholarships Family Planning Considering Adoption with PH The Adoption ... Young Adult Issues Dating and Relationships College and Scholarships Family Planning Considering Adoption with PH The Adoption ...

  13. MM Caregiver Grief Inventory Thomas M. Meuser, Ph.D., University of Missouri St. Louis Samuel J. Marwit, Ph.D., University of Missouri-St. Louis (Emeritus)

    E-print Network

    6 I don't know what is happening. I feel confused and unsure. 1 2 3 4 5 C 7 I carry a lot of stress in life. 1 2 3 4 5 Cr 23 It's a life phase and I know we'll get through it. 1 2 3 4 5 Cr 24 My extended, sick feeling knowing that my loved one is "gone". 1 2 3 4 5 B 10 I feel anxious and scared. 1 2 3 4 5 C

  14. The same-source parallel MM{sub 5}.

    SciTech Connect

    Michalakes, J.

    1999-08-23

    The set of architectures available to users of the Penn State/NCAR MM5 has been expanded to included distributed-memory parallel computers, providing cost-effective scalable performance and memory capacity for large problem sizes. The same-source approach uses high-level parallel library and source-translation technology for adapting MM5, simplifying maintenance and allowing new physics modules to be incorporated without modification. The approach facilitates maintenance of the DM-parallel option to MM5 as an option within the official version, rather than as a separate stand-alone version. As a result, the DM-parallel option to MM5 (now at Version 3.1) has been a part of six subsequent model releases since MM5 Version 2.8 in March 1998. The same-source approach is applicable to other, similarly constructed codes when there is a need or desire to develop the code for distributed memory parallel machines without impacting the pre-existing source code. The approach is also compatible with pre-existing loop-level multithreading directives so that the code will run in distributed-memory/shared-memory mode on SMP clusters.

  15. The pH scale

    NSDL National Science Digital Library

    Olivia Worland (Purdue University; Biological Sciences)

    2008-05-26

    Some animals tolerate broad changes in pH well while others do not. Human activities can create acid rain. Acid rain can change the pH of the environment and destroy entire ecosystems and habitats. For an ecosystem to function properly, its pH must be able to accommodate all of the organisms living in it.

  16. Urine pH test

    MedlinePLUS

    A urine pH test measures the level of acid in urine. ... pH - urine ... meat products or cranberries can decrease your urine pH. ... to check for changes in your body's acid levels.It may be done to ... more effective when urine is acidic or non-acidic (alkaline).

  17. (ISLiM) 2011 (2011.12.21-22) Platypus MM/CG

    E-print Network

    Fukai, Tomoki

    #12;15 (ISLiM) 2011 (2011.12.21-22) 1 Platypus MM/CG 1982 3 1982 8 Cornell 1986 2 1988 4 1996 4 2001 4 2006 10 2011 4 HPCI #12;16 (ISLiM) 2011 (2011.12.21-22) 2 Platypus MM/CG 1. QM MM MM CG QM-MM-CG 3 QM MM QM/MM MM CG MM/CG 2. 2.1 ProteinDF QM DFT B3LYP 8,000 6 c 2.2 Platypus-QM/MM QM/MM QM MM QM

  18. Molecular mechanics (MM3) calculations on phosphonamidate compounds

    NASA Astrophysics Data System (ADS)

    Sakakibara, K.; Shimazaki, K.; Chen, K.-H.; Lii, J.-H.

    2000-12-01

    Phosphonamidate compounds are regarded as transition-state analogs for amide hydrolysis reactions and can be used as potent haptens to elicit catalytic antibodies. The MM3 force field has been extended to cover these compounds, based on the structures, conformational energies, and vibrational analyses from MP2/6-31G ? or B3LYP/6-31G ? calculations. It was necessary to include a "trans-lone pair effect" in the MM3 force field so that the conformational dependence of the N-P and P-C bond lengths could be reproduced. This effect is similar to the Bohlman effect and the anomeric effect. The MM3-calculated molecular structures agree well with the quantum mechanics results, and the conformational equilibria and vibrational spectra are in fair agreement.

  19. Peacemaker: Fracture assessment of a 155mm cannon barrel

    SciTech Connect

    Zywicz, E.

    1993-10-07

    A single crack 30 mm or deeper which is 75 mm long is sufficient to fracture a typical 155 mm cannon barrel with a pressure at or above two-thirds (206 MPa -- 30 ksi) of the maximum operating pressure (310 MPa -- 45 ksi). Longer and deeper flaws reduce the critical pressure required to initiate fracture. For the monolithic barrel design considered in this work, the postulated 30 mm deep by 75 mm long crack should propagate through the entire wall and, depending upon the new ``fractured`` geometry, may propagate axially down the cannon barrel. Numerical analyses conducted with straight through-thickness crack fronts propagated axially at pressures below the maximum operating pressure while those with curved crack fronts required pressures in excess of the working pressures to extend axially. (Experiments on actual 155 mm barrels with flaws similar to the one generated by the tested shape charge show appreciable axial crack extension at approximately equivalent pressures.) In either case, a through-thickness ``hole`` will be formed in the barrel`s side and a reduction in firing pressure should result. Finally, debris deposited within the barrel can greatly assist the fracture process, especially at lower operating pressures. Overall, a single deep and long interior crack appears the most effective way to fracture a cannon barrel. Unless clustered very closely together, multiple ``shallow`` cracks require higher pressures to fracture than does a single deep crack. Flaws introduced on the barrel`s exterior are less efficient since no crack-face pressures exist and the overall stresses on the barrel`s exterior are much lower than on its interior. Thus, very deep exterior cracks would be required to fail the barrel from internal pressure.

  20. 450mm wafer patterning with jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Thompson, Ecron; Hellebrekers, Paul; Hofemann, Paul; LaBrake, Dwayne L.; Resnick, Douglas J.; Sreenivasan, S. V.

    2013-09-01

    The next step in the evolution of wafer size is 450mm. Any transition in sizing is an enormous task that must account for fabrication space, environmental health and safety concerns, wafer standards, metrology capability, individual process module development and device integration. For 450mm, an aggressive goal of 2018 has been set, with pilot line operation as early as 2016. To address these goals, consortiums have been formed to establish the infrastructure necessary to the transition, with a focus on the development of both process and metrology tools. Central to any process module development, which includes deposition, etch and chemical mechanical polishing is the lithography tool. In order to address the need for early learning and advance process module development, Molecular Imprints Inc. has provided the industry with the first advanced lithography platform, the Imprio® 450, capable of patterning a full 450mm wafer. The Imprio 450 was accepted by Intel at the end of 2012 and is now being used to support the 450mm wafer process development demands as part of a multi-year wafer services contract to facilitate the semiconductor industry's transition to lower cost 450mm wafer production. The Imprio 450 uses a Jet and Flash Imprint Lithography (J-FILTM) process that employs drop dispensing of UV curable resists to assist high resolution patterning for subsequent dry etch pattern transfer. The technology is actively being used to develop solutions for markets including NAND Flash memory, patterned media for hard disk drives and displays. This paper reviews the recent performance of the J-FIL technology (including overlay, throughput and defectivity), mask development improvements provided by Dai Nippon Printing, and the application of the technology to a 450mm lithography platform.

  1. Computational Modeling in Plasma Processing for 300 mm Wafers

    NASA Technical Reports Server (NTRS)

    Meyyappan, Meyya; Arnold, James O. (Technical Monitor)

    1997-01-01

    Migration toward 300 mm wafer size has been initiated recently due to process economics and to meet future demands for integrated circuits. A major issue facing the semiconductor community at this juncture is development of suitable processing equipment, for example, plasma processing reactors that can accomodate 300 mm wafers. In this Invited Talk, scaling of reactors will be discussed with the aid of computational fluid dynamics results. We have undertaken reactor simulations using CFD with reactor geometry, pressure, and precursor flow rates as parameters in a systematic investigation. These simulations provide guidelines for scaling up in reactor design.

  2. RF and mm-Wave Photonics at Sandia National Laboratories

    SciTech Connect

    Vawter, G.A.; Sullivan, C.

    1999-07-08

    RF and mm-wave photonic devices and circuits have been developed at Sandia National Laboratories for applications ranging from RF optical data links to optical generation of mm-wave frequencies. This talk will explore recent high-speed photonics technology developments at Sandia including: (1) A monolithic optical integrated circuit for all-optical generation of mm-waves. Using integrated mode-locked diode lasers, amplifiers, and detectors, frequencies between 30 GHz and 90 GHz are generated by a single monolithic (Al,Ga)As optical circuit less than 2mm in its largest dimension. (2) Development of polarization-maintaining, low-insertion-loss, low v-pi, Mach-Zehnder interferometer (MZI) modulators with DC-to-potentially-K-band modulation bandwidth. New low-loss polarization-maintaining waveguide designs using binary alloys have been shown to reduce polarization crosstalk in undoped (Al,Ga)As waveguides, yielding high extinction ratio (>40dB) and low on-chip loss (<6dB) in Mach-Zehnder interferometers. RF drive voltage is reduced through use of 45rnrn-active length devices with modulator sensitivity, v-pi, less than 3V.

  3. Evaluation of Polar MM5 simulations of Greenland's atmospheric circulation

    Microsoft Academic Search

    John J. Cassano; Jason E. Box; David H. Bromwich; Lin Li; Konrad Steffen

    2001-01-01

    A complete annual cycle over the Greenland ice sheet is simulated with the Polar MM5, a mesoscale model optimized for use over extensive ice sheets. These simulations are compiled from a series of short duration (48 hour), forecast mode, simulations. The model output is compared to observations primarily from the Greenland Climate Network automatic weather station (AWS) array. The model

  4. EUV efficiency of a 6000-grooves per mm diffraction grating

    NASA Technical Reports Server (NTRS)

    Hurwitz, Mark; Bowyer, Stuart; Edelstein, Jerry; Harada, Tatsuo; Kita, Toshiaki

    1990-01-01

    In order to explore whether grooves ruled mechanically at a density of 6000 per mm can perform well at EUV wavelengths, a sample grating is measured with this density in an EUV calibration facility. Measurements are presented of the planar uniform line-space diffraction grating's efficiency and large-angle scattering.

  5. Evaluating Patron Satisfaction at the M.M. Bennett Library.

    ERIC Educational Resources Information Center

    Barbier, Pat

    2003-01-01

    Discusses a user satisfaction survey distributed to patrons of the M.M. Bennett Library at St. Petersburg College (Florida). Reports that satisfaction with reference assistance has varied, although there has been an improvement in the rating of library instructions since this question was first posed in 1999. Suggests that paper surveys are easier…

  6. Needlescopic urology: incorporating 2-mm instruments in laparoscopic surgery

    Microsoft Academic Search

    Jon J Soble; Inderbir S Gill

    1998-01-01

    Objectives. To report the initial experience with incorporation of needlescopic (2 mm) instruments and optics in various therapeutic minimally invasive urologic procedures.Methods. Needlescopic techniques were used to successfully perform a variety of urologic surgeries including adrenalectomy, nephrectomy, renal cyst marsupialization, orchiopexy, lymphocele marsupialization, and pelvic lymph node dissection.Results. To date we have performed 42 needlescopic procedures in 39 patients (14

  7. Advisory List of Instructional Media--16MM Films.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of Educational Media.

    These two advisory lists include information on 16mm films appropriate for the K-12 instructional program. In both bibliographies films are listed in the following categories: communication skills; guidance; health, physical education, safety, and sports; science; and social studies. The list for the 1982-1983 school year also includes categories…

  8. IMPLEMENTATION OF AN URBAN CANOPY PARAMETERIZATION IN MM5

    EPA Science Inventory

    The Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model (MM5) (Grell et al. 1994) has been modified to include an urban canopy parameterization (UCP) for fine-scale urban simulations (~1-km horizontal grid spacing). The UCP accounts for drag ...

  9. Signal processing at the mm wave frontier Upamanyu Madhow

    E-print Network

    Liebling, Michael

    between base stations · MultiGigabit wireless mesh backhaul enables dense picocell deployments Need is essential Relay or reflector Objects look bigger at smaller wavelengths (Huygen's principle) Cannot burn flexible beamsteering to form mesh Need five 9s reliability for backhaul #12;mm wave for small cells, stage

  10. BIMA Memo 52 3 mm VLBI at Hat Creek

    E-print Network

    BIMA Memo 52 3 mm VLBI at Hat Creek 1995 ­ 1997 Geoffrey C. Bower, Donald C. Backer, Dick Plambeck at Haystack Observatory serves as the network hub for such observations. Hat Creek has a history of involvement in 3 millimeter â?? VLBI dating back to 1981. Recently, Hat Creek has become reinvolved in VLBI

  11. Dendrochronology Looking Through a 5mm Window of the Past

    E-print Network

    Polly, David

    Dendrochronology Looking Through a 5mm Window of the Past to Predict the Future By: Andy Burnside #12;Abstract The practice of dendrochronology has been a source for dating tree for many years and scientists used the practice of dendrochronology, the technique of dating environmental changes and events

  12. Mineralogic Model (MM3.0) Analysis Model Report

    SciTech Connect

    C. Lum

    2002-02-12

    The purpose of this report is to document the Mineralogic Model (MM), Version 3.0 (MM3.0) with regard to data input, modeling methods, assumptions, uncertainties, limitations and validation of the model results, qualification status of the model, and the differences between Version 3.0 and previous versions. A three-dimensional (3-D) Mineralogic Model was developed for Yucca Mountain to support the analyses of hydrologic properties, radionuclide transport, mineral health hazards, repository performance, and repository design. Version 3.0 of the MM was developed from mineralogic data obtained from borehole samples. It consists of matrix mineral abundances as a function of x (easting), y (northing), and z (elevation), referenced to the stratigraphic framework defined in Version 3.1 of the Geologic Framework Model (GFM). The MM was developed specifically for incorporation into the 3-D Integrated Site Model (ISM). The MM enables project personnel to obtain calculated mineral abundances at any position, within any region, or within any stratigraphic unit in the model area. The significance of the MM for key aspects of site characterization and performance assessment is explained in the following subsections. This work was conducted in accordance with the Development Plan for the MM (CRWMS M&O 2000). The planning document for this Rev. 00, ICN 02 of this AMR is Technical Work Plan, TWP-NBS-GS-000003, Technical Work Plan for the Integrated Site Model, Process Model Report, Revision 01 (CRWMS M&O 2000). The purpose of this ICN is to record changes in the classification of input status by the resolution of the use of TBV software and data in this report. Constraints and limitations of the MM are discussed in the appropriate sections that follow. The MM is one component of the ISM, which has been developed to provide a consistent volumetric portrayal of the rock layers, rock properties, and mineralogy of the Yucca Mountain site. The ISM consists of three components: (1) Geologic Framework Model (GFM); (2) Rock Properties Model (RPM); and (3) Mineralogic Model (MM). The ISM merges the detailed stratigraphy and structural features of the site into a 3-D model that will be useful in primary downstream models and repository design. These downstream models include the hydrologic flow models and the radionuclide transport models. All the models and the repository design, in turn, will be incorporated into the Total System Performance Assessment (TSPA) of the potential nuclear waste repository block and vicinity to determine the suitability of Yucca Mountain as a host for a repository. The interrelationship of the three components of the ISM and their interface with downstream uses are illustrated in Figure 1. The lateral boundaries of the ISM and its three component models are shown in Figure 2.

  13. Spitzer Imaging of Herschel Lensed Sub-mm Galaxies

    NASA Astrophysics Data System (ADS)

    Cooray, Asantha; Wardlow, Julie; Kim, Sam; Khostovan, Ali; Mitchell-Wynne, Ketron; Barton, Elizabeth; Gong, Yan; Amblard, Alexandre; Serra, Paolo; Cooke, Jeff; Riechers, Dominik; Dominic, Benford; Frayer, David; Gardner, Jonathan; Fu, Hai; Bussmann, Shane; Gurwell, Mark; Leeuw, Lerothodi; Pasquale, Temi; Conley, Alex; Bock, Jamie; Vieira, Joaquin; Bridge, Carrie; Glenn, Jason; Zemcov, Michael; Schulz, Bernhard; Shupe, David; Hopwood, Ros; Negrello, Mattia; Andreani, Paola; Clements, David; Dannerbauer, Helmut; de Zotti, Gianfranco; Dunne, Loretta; Dunlop, James; Eales, Steve; Farrah, Duncan; Ivison, Rob; Jarvis, Matt; Maddox, Steve; Michalowski, Michal; Omont, Alain; Perez-Fournon, Ismael; Rigopoulou, Dimitra; Serjeant, Stephen; Smail, Ian; Thompson, Mark; Vaccari, Mattia; Verma, Aprajita; Coppin, Kirsten; Oliver, Seb; Wang, Lingyu

    2011-05-01

    Sub-millimeter surveys have, in the last decade, revealed an unexpected population of high-redshift dust-obscured sub-mm galaxies (SMGs) which are forming stars at a tremendous rate. Due to steep number counts and the negative k-correction at sub-mm wavelengths sub-mm surveys are effective at finding intrinsically faint, gravitationally lensed galaxies. We have now produced a reliable list of about 150 bright lensed SMGs in 200 sq. deg of the Herschel-ATLAS and HerMES (the GTO program of the SPIRE Instrument team) surveys with Herschel-SPIRE. We propose Spitzer IRAC 3.6 and 4.5 micron imaging of 122 of these gravitationally lensed SMGs. The target SMGs are selected to maximally overlap with existing and planned multi-wavelength followup programs, without duplicating existing deep IRAC data. Using the proposed Spitzer data we will: (a) Extend the SEDs of z~ 1 to 5 lensed SMGs into the near-IR regime, where derived stellar masses are more reliable than those estimated at other wavelengths alone; (b) Combine with lens models from existing and planned high-resolution sub-mm imaging (SMA, CARMA, PdBI) to map the evolution of stellar mass as a function of redshift and star-formation rate (SFR); (c) Combine with existing and planned CO and CII molecular line measurements to map the evolution of dust-to-gas and stellar-to-gas mass ratios as a function of redshift and SFR; (d) Obtain snapshot statistics on the sub-mm galaxy evolution from z of 1 to 5 as a function of stellar, dust, and gas mass to study the role of mergers and AGN contribution that may regulate the starburst phenomenon; (e) Compare our results to those from numerical simulations of high-redshift starburst galaxies to investigate the physical conditions in SMGs, and their evolutionary pathways.

  14. Resistance of Streptococcus bovis to acetic acid at low pH: Relationship between intracellular pH and anion accumulation

    SciTech Connect

    Russell, J.B. (Cornell Univ., Ithaca, NY (USA))

    1991-01-01

    Streptococcus bovis JB1, an acid-tolerant ruminal bacterium, was able to grown at pHs from 6.7 to 4.5, and 100 mM acetate had little effect on growth rate or proton motive force across the cell membrane. When S. bovis was grown in glucose-limited chemostats at pH 5.2, the addition of sodium acetate (as much as 100 mM) had little effect on the production of bacterial protein. At higher concentrations of sodium acetate (100 to 360 mM), production of bacterial protein declined, but this decrease could largely be explained by a shift in fermentation products (acetate, formate, and ethanol production to lactate production) and a decline in ATP production (3 ATP per glucose versus 2 ATP per glucose). Y{sub ATP} (grams of cells per mole at ATP) was not decreased significantly even by high concentrations of acetate. Cultures supplemented with 100 mM sodium acetate took up ({sup 14}C)acetate and ({sup 14}C)benzoate in accordance with the Henderson-Hasselbalch equation and gave similar estimates of intracellular pH. As the extracellular pH declined, S. bovis allowed its intracellular pH to decrease and maintained a relatively constant pH gradient across the cell membrane (0.9 unit). The decrease in intracellular pH prevented S. bovis from accumulating large amounts of acetate anion. On the basis of these results it did not appear that acetate was acting as an uncoupler. The sensitivity of other bacteria to volatile fatty acids at low pH is explained most easily by a high transmembrane pH gradient and anion accumulation.

  15. MmTX1 and MmTX2 from coral snake venom potently modulate GABAA receptor activity.

    PubMed

    Rosso, Jean-Pierre; Schwarz, Jürgen R; Diaz-Bustamante, Marcelo; Céard, Brigitte; Gutiérrez, José M; Kneussel, Matthias; Pongs, Olaf; Bosmans, Frank; Bougis, Pierre E

    2015-02-24

    GABAA receptors shape synaptic transmission by modulating Cl(-) conductance across the cell membrane. Remarkably, animal toxins that specifically target GABAA receptors have not been identified. Here, we report the discovery of micrurotoxin1 (MmTX1) and MmTX2, two toxins present in Costa Rican coral snake venom that tightly bind to GABAA receptors at subnanomolar concentrations. Studies with recombinant and synthetic toxin variants on hippocampal neurons and cells expressing common receptor compositions suggest that MmTX1 and MmTX2 allosterically increase GABAA receptor susceptibility to agonist, thereby potentiating receptor opening as well as desensitization, possibly by interacting with the ?(+)/?(-) interface. Moreover, hippocampal neuron excitability measurements reveal toxin-induced transitory network inhibition, followed by an increase in spontaneous activity. In concert, toxin injections into mouse brain result in reduced basal activity between intense seizures. Altogether, we characterized two animal toxins that enhance GABAA receptor sensitivity to agonist, thereby establishing a previously unidentified class of tools to study this receptor family. PMID:25675485

  16. A 10-mm MR-Conditional Unidirectional Pneumatic Stepper Motor

    PubMed Central

    Chen, Yue; Mershon, Christopher D.; Tse, Zion Tsz Ho

    2014-01-01

    Magnetic resonance (MR) conditional robotic devices facilitate accurate interventional procedures under MR imaging (MRI) guidance. For this purpose, a compact (10-mm diameter) MR-conditional stepper motor is presented. The device features seven key components, which contribute to a dense and easy to fabricate design. Alternating bursts of pressurized air and vacuum can drive the motor in 60° per step to achieve a maximum torque of 2.4 mNm. The relationship between torque and angular speed was investigated to demonstrate motor performance under different loading conditions. The stepper motor was tested in a GE 3T MRI scanner to verify its MR-compatibility. A maximum artifact width of 3 mm was measured in MRI images and a maximum signal-to-noise ratio reduction of 2.49% was recorded. PMID:25419104

  17. A 10-mm MR-Conditional Unidirectional Pneumatic Stepper Motor.

    PubMed

    Chen, Yue; Mershon, Christopher D; Tse, Zion Tsz Ho

    2015-04-01

    Magnetic resonance (MR) conditional robotic devices facilitate accurate interventional procedures under MR imaging (MRI) guidance. For this purpose, a compact (10-mm diameter) MR-conditional stepper motor is presented. The device features seven key components, which contribute to a dense and easy to fabricate design. Alternating bursts of pressurized air and vacuum can drive the motor in 60° per step to achieve a maximum torque of 2.4 mNm. The relationship between torque and angular speed was investigated to demonstrate motor performance under different loading conditions. The stepper motor was tested in a GE 3T MRI scanner to verify its MR-compatibility. A maximum artifact width of 3 mm was measured in MRI images and a maximum signal-to-noise ratio reduction of 2.49% was recorded. PMID:25419104

  18. A Pin Diode for mm-Wave Digital Modulation

    Microsoft Academic Search

    W. O. Schlosser; J. P. Beccone; R. S. Riggs

    1970-01-01

    The object of this paper is to show that a switch using PIN diodes is especially well suited for mm-wave high speed digital modulation. The PIN diodes to be described have a switching speed of less than 0.7 nsec and a power handling capability in excess of 200 mW. The quoted switching speed is realized with a transistorized driver consuming

  19. Wave propagation in a piezoelectric rod of 6 mm symmetry

    Microsoft Academic Search

    J. P. Wei; X. Y. Su

    2005-01-01

    The wave propagation in a piezoelectric rod of 6mm symmetry is investigated by applying a 3-D piezoelectric elastic model. A self-adjoint method is introduced to solve this problem, this method avoids calculating the generalized eigenvalue equation, it completely draws the dispersion curves in the forms of Quasi-P wave, Quasi-SV wave and Quasi-SH wave under the self-adjoint boundary condition, and it

  20. Over 1.0 mm-long boron nitride nanotubes

    Microsoft Academic Search

    Hua Chen; Ying Chen; Yun Liu; Lan Fu; Cheng Huang; David Llewellyn

    2008-01-01

    Over 1.0mm boron nitride nanotubes (BNNTs) were successfully synthesized by an optimized ball milling and annealing method. The annealing temperature of 1100°C is crucial for the growth of the long BNNTs because at this temperature there is a fast nitrogen dissolution rate in Fe and the B\\/N ratio in Fe is 1. Such long BNNTs enable a reliable single tube

  1. A 4MM-Wave composite mode multimode conical feedhorn

    Microsoft Academic Search

    Zhisheng Lin; Zhengmi Du; Shener Chen

    1996-01-01

    A 4MM-Wave composite mode multimode conical feedhorn has been developed. Its mode-ratios are calculated and its formulas of the radiation patterns are derived. The measurement results of one and two dimension radiation patterns, measured by the automatic measurement system which we had researched, and the properties of band width and sidelobe are given. Theoretical analyses and measurements show that at

  2. Sub-mm clues to elliptical galaxy formation

    E-print Network

    James S. Dunlop

    2000-11-03

    There is growing evidence that, at the S(850) high redshift, then they should presumably be found among the brighter, S(850) ~ 10 mJy sub-mm sources which are undoubtedly not part of the Lyman-break population. A first powerful clue that this is indeed the case comes from our major SCUBA survey of radio galaxies, which indicates that massive dust-enshrouded star-formation in at least this subset of massive ellipticals is largely confined to z > 2.5, with a mean redshift z = 3.5. While radio selection raises concerns about bias, I argue that our current knowledge of the brightest (S(850) ~ 10 mJy) sub-mm sources detected in unbiased SCUBA imaging surveys indicates that they are also largely confined to this same high-z regime. Consequently, while the most recent number counts imply such extreme sources can contribute only 5-10% of the sub-mm background, their comoving number density (in the redshift band 3 x 10^{-5} per cubic megaparsec, sufficient to account for the formation of all ellipticals of comparable mass to radio galaxies (~4L-star) in the present-day universe.

  3. Projected hybrid orbitals: a general QM/MM method.

    PubMed

    Wang, Yingjie; Gao, Jiali

    2015-01-22

    A projected hybrid orbital (PHO) method was described to model the covalent boundary in a hybrid quantum mechanical and molecular mechanical (QM/MM) system. The PHO approach can be used in ab initio wave function theory and in density functional theory with any basis set without introducing system-dependent parameters. In this method, a secondary basis set on the boundary atom is introduced to formulate a set of hybrid atomic orbtials. The primary basis set on the boundary atom used for the QM subsystem is projected onto the secondary basis to yield a representation that provides a good approximation to the electron-withdrawing power of the primary basis set to balance electronic interactions between QM and MM subsystems. The PHO method has been tested on a range of molecules and properties. Comparison with results obtained from QM calculations on the entire system shows that the present PHO method is a robust and balanced QM/MM scheme that preserves the structural and electronic properties of the QM region. PMID:25317748

  4. High Rate Proton Irradiation of 15mm Muon Drifttubes

    NASA Astrophysics Data System (ADS)

    Zibell, A.; Biebel, O.; Hertenberger, R.; Ruschke, A.; Schmitt, Ch.; Kroha, H.; Bittner, B.; Schwegler, P.; Dubbert, J.; Ott, S.

    2012-08-01

    Future LHC luminosity upgrades will significantly increase the amount of background hits from photons, neutrons 11.11d protons in the detectors of the ATLAS muon spectrometer. At the proposed LHC peak luminosity of 5\\cdot 1034(1)/(cm2s), background hit rates of more than 10(kHz)/(cm2) are expected in the innermost forward region, leading to a loss of performance of the current tracking chambers. Based on the ATLAS Monitored Drift Tube chambers, a new high rate capable drift tube detecor using tubes with a reduced diameter of 15mm was developed. To test the response to highly ionizing particles, a prototype chamber of 46 15mm drift tubes was irradiated with a 20 MeV proton beam at the tandem accelerator at the Maier-Leibnitz Laboratory, Munich. Three tubes in a planar layer were irradiated while all other tubes were used for reconstruction of cosmic muon tracks through irradiated and nonirradiated parts of the chamber. To determine the rate capability of the 15mm drifttubes we investigated the effect of the proton hit rate on pulse height, efficiency and spatial resolution of the cosmic muon signals.

  5. Size Structure and Catch Rates of White Crappie, Black Crappie, and Bluegill in Trap Nets with 13-mm and 16-mm Mesh

    Microsoft Academic Search

    Jeffrey J. Jackson; Daryl L. Bauer

    2000-01-01

    We compared catch rates and size structure of white crappie Pomoxis annularis, black crappie P. nigromaculatus, and bluegill Lepomis macrochirus captured in trap nets with mesh sizes of 13 and 16 mm. We found that trap nets with 13-mm mesh caught significantly more white crappies less than 130 mm total length (TL) and bluegills less than 80 mm TL than

  6. Tzvi Tzfira, Ph.D. Vitaly Citovsky, Ph.D.

    E-print Network

    Citovsky, Vitaly

    #12;Tzvi Tzfira, Ph.D. Vitaly Citovsky, Ph.D. Department of Biochemistry and Cell Biology State Bioscience / Eurekah.com, 810 South Church Street Georgetown, Texas, U.S.A. 78626 Phone: 512/ 863 7762; FAX selection and dosage and the specifications and usage of equipment and devices, as set forth in this book

  7. Ph.D. Mathematical Sciences Ph.D. Mathematical Sciences

    E-print Network

    Hemmers, Oliver

    Ph.D. Mathematical Sciences Program Ph.D. Mathematical Sciences Department(s) Mathematical Sciences. Number for later reference. 1. Students will have a broad understanding of several areas of mathematical to understand, analyze, create, and write mathematical proofs. 3. Students will be able to study and understand

  8. Ph.D. Physics Program Ph.D. in Physics

    E-print Network

    Hemmers, Oliver

    Ph.D. Physics Program Ph.D. in Physics Department(s) Physics and Astronomy College Sciences Program Assessment Coordinator Michael Pravica pravica@physics.unlv.edu 895-1723 Five-Year Implementation Dates (2010 for physics at the graduate level 4. understand statistical physics at the graduate level 5. perform

  9. Permeant cations and blockers modulate pH gating of ROMK channels.

    PubMed

    Sackin, H; Vasilyev, A; Palmer, L G; Krambis, M

    2003-02-01

    External potassium (K) activates the inward rectifier ROMK (K(ir)1.1) by altering the pH gating of the channel. The present study examines this link between external K and internal pH sensitivity using both the two-electrode voltage clamp and the perfused, cut-open Xenopus oocyte preparation. Elevating extracellular K from 1 mM to 10 mM to 100 mM activated ROMK channels by shifting their apparent pK(a) from 7.2 +/- 0.1 (n = 6) in 1 mM K, to 6.9 +/- 0.02 (n = 5) in 10 mM K, and to 6.6 +/- 0.03 (n = 5) in 100 mM K. At any given internal pH, the number of active ROMK channels is a saturating function of external [K]. Extracellular Cs (which blocks almost all inward K current) also stimulated outward ROMK conductance (at constant 1 mM external K) by shifting the apparent pK(a) of ROMK from 7.2 +/- 0.1 (n = 6) in 1 mM K to 6.8 +/- 0.01 (n = 4) in 1 mM K + 104 mM Cs. Surprisingly, the binding and washout of the specific blocker, Tertiapin-Q, also activated ROMK in 1 mM K and caused a comparable shift in apparent pK(a). These results are interpreted in terms of both a three-state kinetic model and a two-gate structural model that is based on results with KcsA in which the selectivity filter can assume either a high or low K conformation. In this context, external K, Cs, and Tertiapin-Q activate ROMK by destabilizing the low-K (collapsed) configuration of the selectivity filter. PMID:12547773

  10. The Intracellular pH of Clostridium paradoxum, an Anaerobic, Alkaliphilic, and Thermophilic Bacterium

    PubMed Central

    Cook, G. M.; Russell, J. B.; Reichert, A.; Wiegel, J.

    1996-01-01

    When the extracellular pH was increased from 7.6 to 9.8, Clostridium paradoxum, a novel alkalithermophile, increased its pH gradient across the cell membrane ((Delta)pH, pH(infin) - pH(infout)) by as much as 1.3 U. At higher pH values (>10.0), the (Delta)pH and membrane potential ((Delta)(psi)) eventually declined, and the intracellular pH increased significantly. Growth ceased when the extracellular pH was greater than 10.2 and the intracellular pH increased to above 9.8. The membrane potential increased to 110 (plusmn) 8.6 mV at pH 9.1, but the total proton motive force ((Delta)p) declined from about 65 mV at pH 7.6 to 25 mV at pH 9.8. Between the extracellular pH of 8.0 and 10.3, the intracellular ATP concentration was around 1 mM and decreased at lower and higher pH values concomitantly with a decrease in growth rate. PMID:16535469

  11. BIOLOGY OF REPRODUCTION 39, 1129-1136 (1988) The Interaction of pH and Cyclic Adenosine 35'-Monophosphate on

    E-print Network

    Lindemann, Charles

    BIOLOGY OF REPRODUCTION 39, 1129-1136 (1988) 1129 The Interaction of pH and Cyclic Adenosine 35), and a high concentration of Mg-adenosine 5'-triphosphate (A TP, 8 mM), demembranated sperm at pH 6.8 and 7AMP-dependent kinase system, and the internal free calcium concentration must be low. INTRODUCTION Detergent

  12. Lambmeat colour values (HunterLab CIE and reflectance) are influenced by aperture size (5 mm v. 25 mm).

    PubMed

    Holman, Benjamin W B; Ponnampalam, Eric N; van de Ven, Remy J; Kerr, Matthew G; Hopkins, David L

    2015-02-01

    The effect of aperture size on the assessment of lamb meat colour values (L*, a*, b* and R630/580)was investigated. Two experiments using 2 HunterLab MiniScan colorimeters (large [25 mm] and small [5 mm] apertures) were conducted: 1) coloured tiles were measured and 2) unaged lamb (n = 65) m. longissimus lumborum (LL) and m. semimembranosus (SM) muscles were measured over 2.5 d under simulated retail display. For Experiment three, 2 different colorimeters were used on lamb (n = 36) LL aged for 6 weeks before measurement over 4 don simulated retail display. Coloured tile a* and b* values were unaffected by aperture size, but L* values and the R630/580 ratio were influenced by aperture size. The effect of aperture size on lamb meat colour measurements varied with display time and muscle type. The large aperture size generally provided the highest colorimetric values, and is recommended for measuring lamb meat colour. PMID:25460126

  13. The pH Game.

    ERIC Educational Resources Information Center

    Chemecology, 1996

    1996-01-01

    Describes a game that can be used to teach students about the acidity of liquids and substances around their school and enable them to understand what pH levels tell us about the environment. Students collect samples and measure the pH of water, soil, plants, and other natural material. (DDR)

  14. Jeanne Murhpy, PhD

    Cancer.gov

    Jeanne Murphy, PhD, CNM is a postdoctoral Cancer Prevention Fellow in the Breast and Gynecologic Cancer Research Group in the Division of Cancer Prevention. She comes to BGCRG with a PhD from Johns Hopkins University School of Nursing. She also completed a graduate certificate in Health Disparities and Health Inequality at Johns Hopkins Bloomberg School of Public Health.

  15. PH as a stress signal

    Microsoft Academic Search

    Sally Wilkinson

    1999-01-01

    The pH of the xylem sap of plants experiencing a range of environmental conditions can increase by over a whole pH unit. This results in an increased ABA concentration in the apoplast adjacent to the stomatal guard cells in the leaf epidermis, by reducing the ability of the mesophyll and epidermal symplast to sequester ABA away from this compartment. As

  16. Rodent models of pulmonary hypertension: harmonisation with the world health organisation's categorisation of human PH.

    PubMed

    Ryan, J; Bloch, K; Archer, S L

    2011-08-01

    The WHO classification of pulmonary hypertension (PH) recognises five distinct groups, all sharing a mean, resting, pulmonary artery pressure (PAP) > 25 mmHg. The aetiology of PH varies by group (1-pulmonary vascular disease, 2-high left heart filling pressures, 3-hypoxia, 4-unresolved pulmonary embolism and 5-miscellaneous). Inclusion in a group reflects shared histological, haemodynamic and pathophysiological features and has therapeutic implications. Advantages of using rodent models to understand the pathophysiology of human PH and to test experimental therapies include the economy, safety and mechanistic certainty they provide. As rodent models are meant to reflect human PH, they should be categorised by a parallel PH classification and limitations in achieving this ideal recognised. Challenges with rodent models include: accurate phenotypic characterisation (haemodynamics, histology and imaging), species and strain variations in the natural history of PH, and poor fidelity to the relevant human PH group. Rat models of group 1 PH include: monocrotaline (± pneumonectomy), chronic hypoxia + SU-5416 (a VEGF receptor inhibitor) and the fawn-hooded rat (FHR). Mouse models of group 1 PH include: transgenic mice overexpressing the serotonin transporter or dominant-negative mutants of bone morphogenetic protein receptor-2. Group 1 PH is also created by infecting S100A4/Mts1 mice with ?-herpesvirus. The histological features of group 1 PH, but not PH itself, are induced by exposure to Schistosoma mansoni or Stachybotrys chartarum. Group 3 PH is modelled by exposure of rats or mice to chronic hypoxia. Rodent models of groups 2, 4 and 5 PH are needed. Comprehensive haemodynamic, histological and molecular phenotyping, coupled with categorisation into WHO PH groups, enhances the utility of rodent models. PMID:21736677

  17. Photodynamic therapy for Barrett's esophagus using a 20-mm diameter light-delivery balloon

    NASA Astrophysics Data System (ADS)

    Panjehpour, Masoud; Overholt, Bergein F.; Phan, Mary N.; Haydek, John M.; Robinson, Amy R.

    2002-06-01

    Background and Objective: Patients with high grade dysplasia (HGD) in Barrett's esophagus are at a high risk for developing esophageal adenocarcinoma. Esophagectomy is the standard treatment for such patients. The objective of this study was to evaluate the safety and efficacy of photodynamic therapy (PDT) using an improved light delivery balloon for ablation of Barrett's esophagus with high grade dysplasia and/or early cancer. Materials and Methods: 20 patients with HGD or early cancer (19 with HGD, 1 with T1 cancer) received 2 mg/kg of porfimer sodium, intravenously. Two to three days after the injection, laser light was delivered using a cylindrical diffuser inserted inside a 20-mm diameter reflective esophageal PDT balloon. Initially, the balloon was inflated to a pressure of 80 mm Hg. The balloon pressure was gradually reduced to 30 mm Hg. A KTP/dye laser at 630 nm was used as the light source. Light dose of 115 J/cm was delivered at an intensity of 270 mw/cm. Nodules were pre- treated with an extra 50 J/cm using a short diffuser inserted through the scope. Patients were maintained on PPI therapy to keep the gastric pH higher than 4. Eighteen patients required one treatment, while two patients were treated twice. Follow-up consisted of endoscopy with four quadrant biopsies at every 2 cm of the treated area. Thermal ablation was used to treat small residual islands on the follow-ups. The follow-up endoscopies ranged from 6 to 17 months. Results: On follow-up endoscopy, 12 patients had complete replacement of their Barrett's mucosa with neosquamous mucosa. Five patients had residual non-dysplastic Barrett's mucosa, one had indefinite dysplasia, two had low grad dysplasia. There were no residual HGD or cancers. The average length of Barrett's was reduced from 5.4 cm to 1.2 cm. High balloon pressure resulted in wide variation in PDT response among patients. Lower balloon pressures resulted in more consistent destruction of Barrett's mucosa among patients. Five patients developed strictures which responded well to dilations. One patient developed atrial fibrillation which responded to medications. Conclusions: Photodynamic therapy using a 20 mm diameter balloon was effective for ablation of high grade dysplasia and early cancer in Barrett's esophagus. Low balloon inflation pressure was a critical parameter in producing consistent tissue destruction.

  18. Formation of asteroids from mm-cm sized grains

    NASA Astrophysics Data System (ADS)

    Carrera, D.; Johansen, A.; Davies, M. B.

    2014-03-01

    Context. Asteroids and comets are intricately connected to life in the universe. Asteroids are the building blocks of terrestrial planets; water-rich asteroids and comets are likely to be the primary source of water for Earth's oceans and other volatiles (Morbidelli et al. 2000; Hartogh et al. 2011); and they may play role in mass extinctions. Yet, the formation of these objects is poorly understood. There is mounting evidence that the traditional picture of the formation of asteroids must be revised. The size distribution of asteroids is hard to reconcile with a traditional bottomup formation scenario. Instead, asteroids may form top-down, with large 100 - 1000 km sized objects forming first by the gravitational collapse of dense clumps of small particles. Experiments and simulations suggest that dust grains cannot grow to sizes larger than mm-cm in protoplanetary disks (Zsom et al. 2010). Also, primitive meteorites from the asteroid belt contain a large mass fraction in chondrules of sizes from 0.1 mm to a few mm. Hence, it is desirable to find a model for asteroid formation from mm-sized particles. Aims. In this work, we model the dynamics of mm-cm sized grains in dust-enriched inner regions of protoplanetary disks. We model the dust-gas interaction to determine whether dust grains of this size can form dense, self-gravitating clouds that can collapse to form asteroids. Methods. We perform shearing box simulations of the inner disk using the Pencil Code (Brandenburg & Dobler 2002). The simulations start with a Solar-type solids-to-gas ratio of 0.01 and we gradually increase the particle concentration. In a real protoplanetary disk, solid particles are expected to migrate from the outer regions and concentrate in the inner disk. Results. Our simulations show that mm-sized particles can form very dense clumps, driven by a run-away convergence in the radial-drift flow of these particles - this dynamic is known as the streaming instability (Youdin & Goodman 2005; Johansen et al. 2007). We show that the streaming instability can also occur for small grains, strongly coupled to the surouning gas. We further show that the resulting particle clumps can reach the density where gravitational collapse is expected to take place, giving rise to planetesimals and asteroids. This process requires either a very high solids-to-gas ratio, or a reduced background pressure gradient, such as that produced by large-scale pressure bumps in the disk. Interpretation. This result offers a promising avenue to the formation of asteroids and comets. Additional work with this model may provide insight on the initial distribution of the masses and orbits of asteroids and comets. This information is important because these are the initial conditions for the formation of terrestrial planets, and for the delivery of water and other volatiles to rocky planets in the habitable zone.

  19. ISL 500 kJ 15 mm railgun numerical simulation

    NASA Astrophysics Data System (ADS)

    Kienner, Philippe; Kitzinger, Klaus

    1993-01-01

    The study presents a numerical simulation of the mechanical and electromagnetic behavior of a 15-mm round bore railgun. The electromagnetic calculations were performed with the MSC/EMAS finite element code. The calculated electromagnetic forces acting on the structure serve as an input for the MSC/DYNA finite element code. The theoretical results are compared to the experimental measurements on the 400-kJ drive railgun. This model is used to compare the behavior of a solid armature with the current input at the backside to front-fed solid armatures. Several optimizations of the present design are proposed.

  20. Hans Peter Schwefel Wireless Networks I, Spring 2005: MM4, Advanced Mobility Support

    E-print Network

    Schwefel, Hans-Peter

    Introduction into security aspects (hps) · Mm2 ad-hoc networks I (TKM) · Mm3 ad-hoc networks II (TKM) · Mm4 Advanced Mobility Topics (HPS) · Mm5 Simulation Techniques and Measurements (HPS) www.kom.auc.dk/~tatiana/ www.kom.auc.dk/~hps/ Page 2 Hans Peter Schwefel Wireless Networks I, Spring 2005: MM4, Advanced

  1. Do patients with rectosigmoid adenomas 5 mm or less in diameter need total colonoscopy?

    Microsoft Academic Search

    Stefania Sciallero; Luigina Bonelli; Hugo Aste; Tino Casetti; Elisabetta Bertinelli; Stefania Bartolini; Roberto Parri; Guido Castiglione; Paola Mantellini; Massimo Costantini; Carlo Naldoni; Paolo Bruzzi

    1999-01-01

    Background: The need for colonoscopy in the care of patients with rectosigmoid adenoma 5 mm or less in diameter is still debatable. Methods: We estimated the prevalence of proximal adenomas among 3052 consecutive subjects undergoing total colonoscopy. Rectosigmoid adenoma was classified as diminutive (5 mm), small (6 to 10 mm), or large (?11 mm). Advanced proximal adenoma was 10 mm

  2. Resonant biaxial 7-mm MEMS mirror for omnidirectional scanning

    NASA Astrophysics Data System (ADS)

    Hofmann, U.; Aikio, M.; Janes, J.; Senger, F.; Stenchly, V.; Weiss, M.; Quenzer, H.-J.; Wagner, B.; Benecke, W.

    2013-03-01

    Low-cost automotive laser scanners for environment perception are needed to enable the integration of advanced driver assistant systems (ADAS) into all automotive vehicle segments, a key to reducing the number of traffic accidents on roads. An omnidirectional 360 degree laser scanning concept has been developed based on combination of an omnidirectional lens and a biaxial large aperture MEMS mirror. This omnidirectional scanning concept is the core of a small sized low-cost time-of-flight based range sensor development. This paper describes concept, design, fabrication and first measurement results of a resonant biaxial 7mm gimbal-less MEMS mirror that is electrostatically actuated by stacked vertical comb drives. Identical frequencies of the two resonant axes are necessary to enable the required circle scanning capability. A tripod suspension was chosen since it allows minimizing the frequency splitting of the two resonant axes. Low mirror curvature is achieved by a thickness of the mirror of more than 500 ?m. Hermetic wafer level vacuum packaging of such large mirrors based on multiple wafer bonding has been developed to enable to achieve a large mechanical tilt angle of +/- 6.5 degrees in each axis. The 7mm-MEMS mirror demonstrates large angle circular scanning at 1.5kHz.

  3. QM/MM molecular dynamics studies of metal binding proteins.

    PubMed

    Vidossich, Pietro; Magistrato, Alessandra

    2014-01-01

    Mixed quantum-classical (quantum mechanical/molecular mechanical (QM/MM)) simulations have strongly contributed to providing insights into the understanding of several structural and mechanistic aspects of biological molecules. They played a particularly important role in metal binding proteins, where the electronic effects of transition metals have to be explicitly taken into account for the correct representation of the underlying biochemical process. In this review, after a brief description of the basic concepts of the QM/MM method, we provide an overview of its capabilities using selected examples taken from our work. Specifically, we will focus on heme peroxidases, metallo-?-lactamases, ?-synuclein and ligase ribozymes to show how this approach is capable of describing the catalytic and/or structural role played by transition (Fe, Zn or Cu) and main group (Mg) metals. Applications will reveal how metal ions influence the formation and reduction of high redox intermediates in catalytic cycles and enhance drug metabolism, amyloidogenic aggregate formation and nucleic acid synthesis. In turn, it will become manifest that the protein frame directs and modulates the properties and reactivity of the metal ions. PMID:25006697

  4. QM/MM Molecular Dynamics Studies of Metal Binding Proteins

    PubMed Central

    Vidossich, Pietro; Magistrato, Alessandra

    2014-01-01

    Mixed quantum-classical (quantum mechanical/molecular mechanical (QM/MM)) simulations have strongly contributed to providing insights into the understanding of several structural and mechanistic aspects of biological molecules. They played a particularly important role in metal binding proteins, where the electronic effects of transition metals have to be explicitly taken into account for the correct representation of the underlying biochemical process. In this review, after a brief description of the basic concepts of the QM/MM method, we provide an overview of its capabilities using selected examples taken from our work. Specifically, we will focus on heme peroxidases, metallo-?-lactamases, ?-synuclein and ligase ribozymes to show how this approach is capable of describing the catalytic and/or structural role played by transition (Fe, Zn or Cu) and main group (Mg) metals. Applications will reveal how metal ions influence the formation and reduction of high redox intermediates in catalytic cycles and enhance drug metabolism, amyloidogenic aggregate formation and nucleic acid synthesis. In turn, it will become manifest that the protein frame directs and modulates the properties and reactivity of the metal ions. PMID:25006697

  5. Single Crystal Si Passive Optical Components for mm-Astronomy

    NASA Astrophysics Data System (ADS)

    Brown, Ari; Chervenak, James; Chuss, David; Wollack, Edward; Henry, Ross; Moseley, S. Harvey

    2006-03-01

    Construction of ultrasensitive, cryogenic-focal-planes for mm-radiation detection requires simultaneous maximization of detector quantum efficiency and minimization of stray light effects, e.g., optical ``ghosting''. To achieve this task in the focal plane detector arrays of the Atacama Cosmology Telescope, integration of two technologies are envisioned; (1) an antireflective (AR) coating for reducing ghosting from the reflected component and increasing absorption at the focal plane, and (2) a backside absorber for suppressing reflections of the transmitted component. We propose a novel approach, involving single crystal Si components, to fabricate AR coatings and backside absorbers. AR coatings are made from Si dielectric honeycombs, in which their dielectric constant may be tuned via honeycomb dimension and wall thickness. Backside absorbers consist of AR Si honeycomb coated-resistors, and the resistors consist of P-implanted Si wafers. This approach enables us to circumvent the mechanical complexities arising from thermal expansion effects, because the detector array, back-short, and AR coating are fabricated out of the same material. We also extend the functionality of single crystal Si in the field of mm-radiation detection by fabricating curved, low-loss, broadband waveguides. These waveguides may enable compact structures for applications requiring variable pathlength, e.g., interferometric spectroscopy.

  6. Effect of Applied Potentials on Environmental Cracking Behavior of 17-4 PH Stainless Steel Weldments

    Microsoft Academic Search

    K. S. Raja; K. P. Rao

    1995-01-01

    The effects of anodic, cathodic, and open-circuit potentials (OCP) on the environmental cracking behavior of 17% Cr-4% Ni (17-4 [UNS S17400]) precipitation-hardenable (PH) stainless steel (SS) welds subjected to different thermal treatments were studied. Sheets of 17-4 PH SS 1.5 mm thick and in solution-treated condition were full-penetration welded autogenously using the gas tungsten arc welding process (GTAW). Weldments were

  7. Control of ammonia toxicity to Hyalella azteca by sodium, potassium and pH

    Microsoft Academic Search

    Uwe Borgmann; Anne I. Borgmann

    1997-01-01

    The toxicity of ammonia to Hyalella azteca at constant pH in artificial media was controlled by sodium and potassium, and not by calcium, magnesium, or anions. Small increases in the LC50 for total ammonia (from 0.15 to 0.5 mM) occurred as sodium was increased from 0.1 to 1 mM and above, but major increases in the LC50 (to over 10

  8. Effects of ion implantation on friction and wear of stainless steels. [15-5PH

    Microsoft Academic Search

    L. E. Pope; F. G. Yost; D. M. Follstaedt; J. A. Knapp; S. T. Picraux

    1982-01-01

    Friction and wear of 304, 15-5 PH and 440C stainless steels and of pure Fe are shown to be reduced by ion implantation of Ti and C. Mechanically polished samples were ion implanted to fluences of 2 x 10¹⁵ Ti\\/mm² (90 to 180 keV) and 2 x 10¹⁵ C\\/mm² (30 keV); the implantation profiles of the two elements extended to

  9. Characterisation of mechanically milled 17-4 PH gas atomized stainless steel powders

    Microsoft Academic Search

    Cemil Çetinkaya; Tayfun F?nd?k; Sedat Özbilen

    2007-01-01

    A laboratory scale Szegvari type vertical mechanical alloying (MA)\\/mechanical milling (MM) attritor for research purposes was designed and constructed at Gazi University. By using this attritor, optimum processing parameters such as milling time, milling speed (rev\\/min), diameter and the amount of milling balls, milling atmosphere were determined when MM’ing of gas atomized 17-4PH stainless steel powders were carried out. After

  10. Evolution of pH and chemical composition of pore solution in carbonated concrete

    Microsoft Academic Search

    Qi Pu; Linhua Jiang; Jinxia Xu; Hongqiang Chu; Yi Xu; Yan Zhang

    An investigation of carbonation in concrete, the pH and chemical composition change of the pore solution in concrete with different degrees of carbonation, was presented. The concrete samples were manufactured using ordinary portland cement and fly ash with dimension of 100mm diameter by 3mm in height, and six different mix proportions. The concrete samples were exposed to the environment (CO2

  11. Divalent Metals and pH Alter Raltegravir Disposition In Vitro

    PubMed Central

    Moss, Darren M.; Siccardi, Marco; Murphy, Matthew; Piperakis, Michael M.; Khoo, Saye H.; Back, David J.

    2012-01-01

    Raltegravir shows marked pharmacokinetic variability in patients, with gastrointestinal pH and divalent-metal binding being potential factors. We investigated raltegravir solubility, lipophilicity, pKa, and permeativity in vitro to elucidate known interactions with omeprazole, antacids, and food, all of which increase gastric pH. Solubility of raltegravir was determined at pH 1 to 8. Lipophilicity of raltegravir was determined using octanol-water partition. Raltegravir pKa was determined using UV spectroscopy. The effects of pH, metal salts, and omeprazole on the cellular permeativity of raltegravir were determined using Caco-2 monolayers. Cellular accumulation studies were used to determine the effect of interplay between pH and ABCB1 transport on raltegravir accumulation. Samples were analyzed using liquid chromatography-tandem mass spectroscopy (LC-MS/MS) or scintillation counting. Raltegravir at 10 mM was partly insoluble at pH 6.6 and below. Raltegravir lipophilicity was pH dependent and was reduced as pH was increased from 5 to 9. The pKa of raltegravir was 6.7. Raltegravir cellular permeativity was heavily influenced by changes in extracellular pH, where apical-to-basolateral permeativity was reduced 9-fold (P < 0.05) when apical pH was increased from 5 to 8.5. Raltegravir cellular permeativity was also reduced in the presence of magnesium and calcium. Omeprazole did not alter raltegravir cellular permeativity. Cellular accumulation of raltegravir was increased independently by inhibiting ABCB1 and by lowering extracellular pH from pH 8 to 5. Gastrointestinal pH and polyvalent metals can potentially alter the pharmacokinetic properties of raltegravir, and these data provide an explanation for the variability in raltegravir exposure in patients. The evaluation of how divalent-metal-containing products, such as multivitamins, that do not affect gastric pH alter raltegravir pharmacokinetics in patients is now justified. PMID:22450971

  12. Comparison of less lethal 40 mm sponge projectile and the 37 mm projectile for injury assessment on human thorax

    NASA Astrophysics Data System (ADS)

    Nsiampa, N.; Robbe, C.; Oukara, A.; Papy, A.

    2012-08-01

    Since there is an increasing interest in avoiding human body injury in diverse situations like crowd control or peacekeeping missions, less lethal ammunition are more and more used. In this study we focus only on kinetic energy non-lethal (KENLW) projectiles. Their desired effects on human body are the temporary incapacitation through blunt trauma. There are different types of KENLW projectiles ranging from rigid to deformable projectiles. Unfortunately, the effects of such projectiles are not really well known as it is difficult to measure the force transmitted to the human body or the related deformation. Because the potential of injury excludes human living tests, tests are performed on cadavers, animals or human tissue surrogates. Besides these tests, numerical simulations are more and more used to gain more understanding, to assess or to predict the effects of this kind of projectile on human body. In this paper a comparison based on the viscous criterion between the 37 mm rigid projectile and the 40 mm sponge projectile was made.

  13. Modelling and performance of Nb SIS mixers in the 1.3 mm and 0.8 mm bands

    NASA Technical Reports Server (NTRS)

    Karpov, A.; Carter, M.; Lazareff, B.; Billon-Pierron, D.; Gundlach, K. H.

    1992-01-01

    We describe the modeling and subsequent improvements of SIS waveguide mixers for the 200-270 and 330-370 GHz bands (Blundell, Carter, and Gundlach 1988, Carter et al 1991). These mixers are constructed for use in receivers on IRAM radiotelescopes on Pico Veleta (Spain, Sierra Nevada) and Plateau de Bure (French Alps), and must meet specific requirements. The standard reduced height waveguide structure with suspended stripline is first analyzed and a model is validated through comparison with scale model and working scale measurements. In the first step, the intrinsic limitations of the standard mixer structure are identified, and the parameters are optimized bearing in mind the radioastronomical applications. In the second step, inductive tuning of the junctions is introduced and optimized for minimum noise and maximum bandwidth. In the 1.3 mm band, a DSB receiver temperature of less than 110 K (minimum 80 K) is measured from 180 through 260 GHz. In the 0.8 mm band, a DSB receiver temperature of less than 250 K (minimum 175 K) is obtained between 325 and 355 GHz. All these results are obtained with room-temperature optics and a 4 GHz IF chain having a 500 MHz bandwidth and a noise temperature of 14 K.

  14. A densitometric analysis of commercial 35mm films

    NASA Technical Reports Server (NTRS)

    Hammond, Ernest C., Jr.; Ruffin, Christopher, III

    1989-01-01

    IIaO films have been subjected to various sensitometric tests. The have included thermal and aging effects and reciprocity failure studies. In order to compare the special IIaO film with popular brands of 35 mm films and their possible use in astrophotography, Agfa, Fuji and Kodak print and slide formats, as well as black and white and color formats, were subjected to sensitometric, as well as densitometric analysis. A scanning electron microscope was used to analyze grain structure size, and shape as a function of both speed and brand. Preliminary analysis of the grain structure using an ISI-SS40 scanning electron microscope indicates that the grain sizes for darker densities are much larger than the grain size for lighter densities. Researchers analyze the scanning electron microscope findings of the various grains versus densities as well as enhancement of the grains, using the IP-8500 Digital Image Processor.

  15. Multispectral mm-wave imaging: materials and images

    NASA Astrophysics Data System (ADS)

    Alexander, Naomi E.; Callejero Andrés, Carlos; Gonzalo, Ramón

    2008-04-01

    It is well known that millimeter-wave technology provides an important imaging capability through clothing and adverse weather conditions, among others. Alfa Imaging has undertaken a project to study the different applications of mm-wave imaging. An important part of this project is the measurement of material properties of a number of clothing and packaging samples in the frequency range from 40 to 306GHz. This task has been undertaken by the Antenna Group at the Public University of Navarra using an ABmm Network Analyser. The resulting data has been analysed and is presented in this paper along with example images and conclusions on the ideal operating frequency for the various applications studied.

  16. 120-mm supercondcting quadrupole for interaction regions of hadron colliders

    SciTech Connect

    Zlobin, A.V.; Kashikhin, V.V.; Mokhov, N.V.; Novitski, I.; /Fermilab

    2010-05-01

    Magnetic and mechanical designs of a Nb{sub 3}Sn quadrupole magnet with 120-mm aperture suitable for interaction regions of hadron colliders are presented. The magnet is based on a two-layer shell-type coil and a cold iron yoke. Special spacers made of a low-Z material are implemented in the coil mid-planes to reduce the level of radiation heat deposition and radiation dose in the coil. The quadrupole mechanical structure is based on aluminum collars supported by an iron yoke and a stainless steel skin. Magnet parameters including maximum field gradient and field harmonics, Nb3Sn coil pre-stress and protection at the operating temperatures of 4.5 and 1.9 K are reported. The level and distribution of radiation heat deposition in the coil and other magnet components are discussed.

  17. Coupling MM5 with ISOLSM: Development, testing, and applications

    SciTech Connect

    Riley, W.J.; Cooley, H.S.; He, Y.; Torn, M.S.

    2003-06-10

    Surface water and energy fluxes are tightly coupled with CO2 exchanges between the ecosystem and atmosphere. Other surface-to-atmosphere trace-gas exchanges of interest in climate change research (e.g., N2O, CH4, C18OO, and H218O) are also strongly impacted by surface energy exchanges. Further, land-use change has large effects on the surface energy balance and therefore the exchanges of these trace gases. To investigate these issues at the regional scale we have coupled MM5 (Grell et al. 1995) with ISOLSM (Riley et al. 2002, Riley et al. 2003), a land-surface model based on LSM1 (Bonan 1995).

  18. The Apollo 15 coarse fines (4-10 mm)

    NASA Technical Reports Server (NTRS)

    Ryder, Graham; Sherman, Sarah Bean

    1989-01-01

    A new catalog of the Apollo 15 coarse fines particles is presented. Powell's macroscopic descriptions, resulting from his 1972 particle by particle binocular examination of all of the Apollo 15 4 to 10 mm fines samples, are retained. His groupings are also retained, but petrographic, chemical, and other data from later analyses are incorporated into this catalog to better characterize individual particles and describe the groups. A large number of particles have no characterization beyond that done by Powell. Complete descriptions of the particles and all known references are provided. The catalog is intended for anyone interested in the rock types collected by Dave Scott and Jim Irwin in the Hadley-Appenine region, and particularly for researchers requiring sample allocations.

  19. MM Herculis - An eclipsing binary of the RS CVn

    NASA Technical Reports Server (NTRS)

    Sowell, J. R.; Hall, D. S.; Henry, G. W.; Burke, E. W., Jr.; Milone, E. F.

    1983-01-01

    V, B and U differential photoelectric photometry has been obtained for the RS Canum Venaticorum-class eclipsing binary star MM Her, with the light outside the eclipse being Fourier-analyzed to study wave migration and amplitude. These, together with the mean light level of the system, have been monitored from 1976 through 1980. Observations within the eclipse have revealed eclipses to be partial, rather than total as previously thought. The geometric elements of the presently rectified light curve are forced on the pre-1980 light curves and found to be compatible. With these elements, and previously obtained double line radial velocity curves, new absolute dimensions of 1.18 solar masses and 1.58 solar radii are calculated for the hotter star and 1.27 solar masses and 2.83 solar radii for the cooler star. The plotting of color indices on the color-color curve indicates G2V and K2IV spectral types.

  20. Improved mm-wave photometry for kinetic inductance detectors

    NASA Astrophysics Data System (ADS)

    Calvo, M.; Roesch, M.; Désert, F.-X.; Monfardini, A.; Benoit, A.; Mauskopf, P.; Ade, P.; Boudou, N.; Bourrion, O.; Camus, P.; Cruciani, A.; Doyle, S.; Hoffmann, C.; Leclercq, S.; Macias-Perez, J. F.; Ponthieu, N.; Schuster, K. F.; Tucker, C.; Vescovi, C.

    2013-03-01

    Context. We have developed a dual-band (140 and 220 GHz) mm-wave imaging camera based on superconducting kinetic inductance detector (KID) arrays. Each array contains 132 superconducting resonators whose resonant frequencies are shifted by mm-wave photons absorption. The read out is achieved with a single electronics chain per band, taking advantage of the intrinsic KID frequency-domain multiplexability. The arrays are easily scalable and well adapted for future large format focal plane instruments. NIKA (formerly Néel IRAM KID Array, now New IRAM KID Array) has been specifically designed for the IRAM 30 m telescope at Pico Veleta, and is one of the first instruments using KIDs to have made measurements of astronomical sources. Aims: In this Letter we describe the solutions adopted to improve the calibration accuracy and the sensitivity of the instrument, and we report on the outcome of the 3rd NIKA observing run of October, 2011. Methods: We use a fast electronic modulation of the readout tone for each KID pixel in order to linearize the instrument calibration, which we track with measurements of planets. We also adopt a new design of the KIDs, sensitive to both polarizations, to increase the amount of radiation absorbed and thus the optical efficiency of the system. Results: We measured an average sensitivity on the sky of 21 mJys0.5 per beam at 140 GHz and 140 mJys0.5 at 220 GHz in the best observing conditions (?220 ? 0.2) after atmospheric noise decorrelation. The sensitivity at 220 GHz was limited by the atmospheric attenuation and loading as well as a reduction in the spectral bandwidth due to a misplaced filter. We found the repeatability in the photometry over the entire observing run to be better than 10% in both bands, thus demonstrating a significant improvement over the previous runs. We also find good agreement between NIKA measurements of faint astronomical sources and previous measurements of the same sources.

  1. David Cheresh, PhD

    Cancer.gov

    Meetings & Events Home Agenda Speaker Biosketches Abstracts Logistics Contact Speaker Biosketches David Cheresh, PhD(University of California, San Diego) Dr. David Cheresh studies the mechanism of action of signaling networks that regulate

  2. Esophageal pH monitoring

    MedlinePLUS

    pH monitoring - esophageal; Esophageal acidity test ... esophagitis You may need to have the following tests if your doctor suspects esophagitis : Barium swallow Esophagogastroduodenoscopy (also called upper GI endoscopy)

  3. Hickey -TT174, casts 1 to cast 11 Cruise cast lat (dd.mm.m) lon(dd.mm.m) Date/Time (MMDDYYHHMM) Total Scan

    E-print Network

    Hickey, Barbara

    ) Total Scan Depth(m) Pres.(db) Cond. Salinity Temp. Irrad. Atten. Oxygen Sigma-t Dyn.ht. . page 1 #12;Hickey -TT174, casts 1 to cast 11 Cruise cast lat (dd.mm.m) lon(dd.mm.m) Date/Time (MMDDYYHHMM) Total -TT174, casts 1 to cast 11 Cruise cast lat (dd.mm.m) lon(dd.mm.m) Date/Time (MMDDYYHHMM) Total Scan

  4. Regulation of intracellular pH in salamander retinal rods.

    PubMed Central

    Saarikoski, J; Ruusuvuori, E; Koskelainen, A; Donner, K

    1997-01-01

    1. We measured intracellular pH (pHi) in rods isolated from the retina of the axolotl salamander, Ambystoma mexicanum, using the fluorescent indicator 2',7'-bis(carboxyethyl)-5(and -6)-carboxyfluorescein (BCECF). 2. The light exposures associated with data acquisition had no marked effect on pHi. There was no sharp change between the value obtained from the first exposure of dark-adapted rods and subsequent readings. Increasing the acquisition frequency from 1 to 10 min-1 either had no effect, or brought about a slow acidification, which was stopped or reversed when the low frequency was restored. 3. In nominally HCO3(-)-free solution at pH 7.5, the rods had a steady-state pHi of 7.09 +/- 0.02 (n = 46) and a buffering power (beta i) of 24 +/- 1 mM (pH unit)-1 (n = 48). The buffering power was virtually constant in the pH range 6.6-8.0. In the same range, pHi dependent linearly on perfusion pH (pHo) with regression coefficients of 0.4-0.5. 4. There were no significant differences between the inner and outer segment of intact rods as regards steady-state pHi or responses to experimental treatments. 5. Recovery from an intracellular acid load imposed by sodium propionate or an NH4Cl prepulse in nominally bicarbonate-free perfusate was completely blocked by decreasing the extracellular Na+ concentration to 7 mM, and slowed by 86% by applying 1 mM amiloride. 6. Introduction of 2% CO2-13 mM HCO3- caused an alkalinization that was often preceded by a transient acidification. Steady-state pHi was on average 0.1 pH units higher than in nominally bicarbonate-free solution. The mean acid extrusion rate, calculated on the assumption that CO2-HCO3- behaves as an open system, was 19% higher (31 +/- 2 mM h-1) than in a solution buffered only by Hepes (26 +/- 2 mM h-1). 7. In the presence of CO2-HCO3-, 100 microM 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) decreased the acid extrusion rate by 20% on average. Lowering the extracellular Cl-concentration to 7 mM raised pHi, but did not significantly affect the acid extrusion rate. 8. We conclude that retinal rods regulate pHi by both Na(+)-H+ exchange and mechanism(s) involving HCO3(-)-Cl- exchange. In the present conditions, the Na(+)-H+ exchanger appears as the dominant mechanism for acid extrusion. PMID:9023768

  5. GDx-MM: An imaging Mueller matrix retinal polarimeter

    NASA Astrophysics Data System (ADS)

    Twietmeyer, Karen Marie

    2007-12-01

    Retinal diseases are a major cause of blindness worldwide. Although widely studied, disease mechanisms are not completely understood, and diagnostic tests may not detect disease early enough for timely intervention. The goal of this research is to contribute to research for more sensitive diagnostic tests that might use the interaction of polarized light with retinal tissue to detect subtle changes in the microstructure. This dissertation describes the GDx-MM, a scanning laser polarimeter which measures a complete 16-element Mueller matrix image of the retina. This full polarization signature may provide new comparative information on the structure of healthy and diseased retinal tissue by highlighting depolarizing structures as well as structures with varying magnitudes and orientations of retardance and diattenuation. The three major components of this dissertation are: (1) Development of methods for polarimeter optimization and error analysis; (2) Design, optimization, assembly, calibration, and validation of the GDx-MM polarimeter; and (3) Analysis of data for several human subjects. Development involved modifications to a Laser Diagnostics GDx, a commercially available scanning laser ophthalmoscope with incomplete polarization capability. Modifications included installation of polarization components, development of a data acquisition system, and implementation of algorithms to convert raw data into polarization parameter images. Optimization involved visualization of polarimeter state trajectories on the Poincare sphere and a condition number analysis of the instrument matrix. Retinal images are collected non-invasively at 20 mum resolution over a 15° visual field in four seconds. Validation of the polarimeter demonstrates a polarimetric measurement accuracy of approximately +/- 5%. Retinal polarization data was collected on normal human subjects at the University of Arizona and at Indiana University School of Optometry. Calculated polarization parameter images reveal properties of the tissue microstructure. For example, retardance images indicate nerve fiber layer thickness and orientation, and depolarization images (uniform for these normal subjects), are predicted to indicate regions of disease-related tissue disruption. This research demonstrates a method for obtaining a full polarization signature of the retina in one measurement using a polarimetrically optimized instrument, and provides a step toward the use of complete retinal imaging polarimetry in the diagnosis and monitoring of retinal disease.

  6. Heterogeneous Distribution of Microbial Activity in Methanogenic Aggregates: pH and Glucose Microprofiles

    PubMed Central

    Lens, Piet N. L.; De Beer, Dirk; Cronenberg, Carel C. H.; Houwen, Frans P.; Ottengraf, Simon P. P.; Verstraete, Willy H.

    1993-01-01

    Methanogenic aggregates, harvested from an upflow anaerobic sludge blanket reactor treating potato starch wastewater, were acclimatized to either glucose or a mixture of sugars and organic nitrogen compounds (i.e., diluted molasses). Both types of granules exhibited internal pH and substrate concentration gradients in mineral medium (pH 7.0, 30°C) as was measured with microelectrodes. Glucose-acclimatized granules suspended in a mineral medium lacking glucose exhibited a distinct internal pH decrease of about 1 U within the granule, suggesting strong metabolism by the acidogenic bacteria. Molasses-acclimatized and aged granules suspended in mineral medium did not exhibit such a pH decrease, suggesting the importance of the metabolic state of these acidogens. The pH gradient did not occur in deactivated granules and was not observable in strongly buffered media (mineral medium containing 33 mM phosphate or reactor liquid). When glucose (0.5 to 5.0 mM) was added to the mineral medium, granules exhibited a convex pH profile. Glucose consumption was located exclusively in the outer 200 to 300 ?m of the aggregates (mean diameter = 1.5 mm). The addition of 20 mM 2-bromoethanesulfonic acid to the mineral medium indicated that the higher pH levels in the centre of the granule appeared to be related to the activity of methanogens. It is suggested that acidogenic activity occurs predominantly in the outer 200 to 300 ?m of the aggregate and methanogenic activity occurs predominantly in the center of the investigated granules. Images PMID:16349091

  7. Stability of recombinant green fluorescent protein (GFPuv) in glucose solutions at different concentrations and pH values

    Microsoft Academic Search

    Thereza Christina Vessoni Penna; Marina Ishii; Juliana Sayuri Kunimura; Olivia Cholewa

    2005-01-01

    The stability at room temperature (25°C) of recombinant green fluorescent protein (GFPuv), expressed by Escherichia coli cells and isolated by three-phase partitioning extraction with hydrophobic interaction column, was studied. The GFPuv was\\u000a diluted in buffered (each 10 mM: Tris-HCl, pH 8.0; phosphate, pH 6.0 and 7.0 and acetate, pH 5.0) and in unbuffered (water for injection [WFI]; pH 6.70 ±

  8. Stability of Recombinant Green Fluorescent Protein (GFPuv) in Glucose Solutions at Different Concentrations and pH Values

    Microsoft Academic Search

    THEREZA CHRISTINA VESSONI PENNAr; Marina Ishii; Juliana Sayuri Kunimura; Olivia Cholewa

    The stability at room temperature (25°C) of recombinant green fluorescent protein (GFPuv), expressed by Escherichia coli cells and isolated by three-phase partitioning extraction with hydrophobic interaction column, was studied. The GFPuv was\\u000a diluted in buffered (each 10 mM: Tris-HCl, pH 8.0; phosphate, pH 6.0 and 7.0 and acetate, pH 5.0) and in unbuffered (water\\u000a for injection [WFI]; pH 6.70 ±

  9. Mapping protein electron transfer pathways with QM/MM methods

    PubMed Central

    Guallar, Victor; Wallrapp, Frank

    2008-01-01

    Mixed quantum mechanics/molecular mechanics (QM/MM) methods offer a valuable computational tool for understanding the electron transfer pathway in protein–substrate interactions and protein–protein complexes. These hybrid methods are capable of solving the Schrödinger equation on a small subset of the protein, the quantum region, describing its electronic structure under the polarization effects of the remainder of the protein. By selectively turning on and off different residues in the quantum region, we are able to obtain the electron pathway for short- and large-range interactions. Here, we summarize recent studies involving the protein–substrate interaction in cytochrome P450 camphor, ascorbate peroxidase and cytochrome c peroxidase, and propose a novel approach for the long-range protein–protein electron transfer. The results on ascorbate peroxidase and cytochrome c peroxidase reveal the importance of the propionate groups in the electron transfer pathway. The long-range protein–protein electron transfer has been studied on the cytochrome c peroxidase–cytochrome c complex. The results indicate the importance of Phe82 and Cys81 on cytochrome c, and of Asn196, Ala194, Ala176 and His175 on cytochrome c peroxidase. PMID:18445553

  10. ALMA reveals VYCMa's sub-mm maser and dust distribution

    E-print Network

    Richards, A M S; Humphreys, E M; Vlahakis, C; Vlemmings, W; Baudry, A; De Beck, E; Decin, L; Etoka, S; Gray, M D; Harper, G M; Hunter, T R; Kervella, P; Kerschbaum, F; McDonald, I; Melnick, G; Muller, S; Neufeld, D; O'Gorman, E; Parfenov, S Yu; Peck, A B; Shinnaga, H; Sobolev, A M; Testi, L; Uscanga, L; Wootten, A; Yates, J A; Zijlstra, A

    2014-01-01

    Cool, evolved stars have copious, enriched winds. The structure of these winds and the way they are accelerated is not well known. We need to improve our understanding by studying the dynamics from the pulsating stellar surface to about 10 stellar radii, where radiation pressure on dust is fully effective. Some red supergiants have highly asymmetric nebulae, implicating additional forces. We retrieved ALMA Science Verification data providing images of sub-mm line and continuum emission from VY CMa. This enables us to locate water masers with milli-arcsec precision and resolve the dusty continuum. The 658-, 321- and 325-GHz masers lie in irregular, thick shells at increasing distances from the centre of expansion. For the first time this is confirmed as the stellar position, coinciding with a compact peak offset to the NW of the brightest continuum emission. The maser shells (and dust formation zone) overlap but avoid each other on tens-au scales. Their distribution is broadly consistent with excitation models...

  11. Digital Frequency Domain Multiplexer for mm-Wavelength Telescopes

    SciTech Connect

    Spieler, Helmuth G; Dobbs, Matt; Bissonnette, Eric; Spieler, Helmuth G.

    2007-07-23

    An FPGA based digital signal processing (DSP) system for biasing and reading out multiplexed bolometric detectors for mm-wavelength telescopes is presented. This readout system is being deployed for balloon-borne and ground based cosmology experiments with the primary goal of measuring the signature of inflation with the Cosmic Microwave Background Radiation. The system consists of analog superconducting electronics running at 250 mK and 4 K, coupled to digital room temperature backend electronics described here. The digital electronics perform the real time functionality with DSP algorithms implemented in firmware. A soft embedded processor provides all of the slow housekeeping control and communications. Each board in the system synthesizes multi-frequency combs of 8 to 32 carriers in the MHz band to bias the detectors. After the carriers have been modulated with the sky-signal by the detectors, the same boards digitize the comb directly. The carriers are mixed down to base-band and low pass filtered. The signal bandwidth of 0.050Hz-100 Hz places extreme requirements on stability and requires powerful filtering techniques to recover the sky-signal from the MHz carriers.

  12. MEMS Fabricated MM-Wave Slow Wave Structure

    NASA Astrophysics Data System (ADS)

    Field, Mark; Borwick, Robert; Shin, Young-Min; Barnett, Larry; Luhmann, Neville; Kimura, Takuji; Atkinson, John

    2012-02-01

    We report on the fabrication and test of a MEMS slow wave structure designed for a > 40 GHz bandwidth centered on 220 GHz operation, that slows radiation down to group velocity of 8.16 x 10^7 ms-1 where the velocity matches the speed of electrons from a 20 keV source. The slow wave device uses a 40 mm long staggered interdigitated vane structure within a waveguide [1]. Ultimately, such a device will be integrated with an electron beam to become part of a sheet beam travelling wave tube (SBTWT) amplifier. A gold coated deep reactive ion etched (DRIE) silicon test structure was fabricated to test the RF properties of the design. This MEMS structure was coupled to WR-4 waveguide in a metal fixture and the S-parameters measured using a vector network analyzer, allowing extraction of the insertion loss and signal delay as a function of frequency. A further MEMS structure with just 10 cells of the vane structure within a cavity were fabricated which allows points on the dispersion curve to be directly measured as resonances of the structure. Extraction of the dispersion curve verifies the group velocity measurement of the device. [4pt] [1] Y-M. Shin & L.R. Barnett, Appl.Phys. Lett. 2008, 92 pp. 091501.

  13. High resolution mm-VLBI imaging of Cygnus A

    E-print Network

    Boccardi, Bia; Bach, Uwe; Ros, Eduardo; Zensus, J Anton

    2015-01-01

    At a distance of 249 Mpc ($z$=0.056), Cygnus A is the only powerful FR II radio galaxy for which a detailed sub-parsec scale imaging of the base of both jet and counter-jet can be obtained. Observing with VLBI at millimeter wavelengths is fundamental for this object, as it uncovers those regions which appear self-absorbed or free-free absorbed by a circumnuclear torus at longer wavelengths. We performed 7 mm Global VLBI observations, achieving ultra-high resolution imaging on scales down to 90 $\\mu$as. This resolution corresponds to a linear scale of only $\\sim$400 Schwarzschild radii. We studied the transverse structure of the jets through a pixel-based analysis, and kinematic properties of the main emission features by modeling the interferometric visibilities with two-dimensional Gaussian components. Both jets appear limb-brightened, and their opening angles are relatively large ($\\phi_\\mathrm {j}\\sim 10^{\\circ}$). The flow is observed to accelerate within the inner-jet up to scales of $\\sim$1 pc, while lo...

  14. The LMT Galaxies' 3 mm Spectroscopic Survey: First Results

    NASA Astrophysics Data System (ADS)

    Rosa González, D.; Schloerb, P.; Vega, O.; Hunt, L.; Narayanan, G.; Calzetti, D.; Yun, M.; Terlevich, E.; Terlevich, R.; Mayya, Y. D.; Chávez, M.; Montaña, A.; Pérez García, A. M.

    2014-09-01

    The molecular phase of the interstellar medium (ISM) in galaxies offers fundamental insight for understanding star-formation processes and how stellar feedback affects the nuclear activity of certain galaxies. We present here Large Millimeter Telescope spectra obtained with the Redshift Search Receiver, a spectrograph that covers simultaneously the 3 mm band from 74 to 111 GHz with a spectral resolution of around 100 km/s. Our selected galaxies, have been detected previously in HCN, and have different degrees of nuclear activity — one normal galaxy (NGC 6946), the starburst prototype (M82) and two %ultraluminous infrared galaxies (ULIRGs, IRAS 17208-0014 and Mrk 231). We plotted our data in the HCO+/HCN vs. HCN/13CO diagnostic diagram finding that NGC 6946 and M82 are located close to other normal galaxies; and that both IRAS 17208-0014 and Mrk 231 are close to the position of the well known ULIRG Arp 220 reported by Snell et al. (2011). We found that in Mrk 231 - a galaxy with a well known active galactic nucleus - the HCO+/HCN ratio is similar to the ratio observed in normal galaxies.

  15. B.S. to Ph.D. M.S. to Ph.D. Dual-title Ph.D.

    E-print Network

    -centered care For More Information Marsha Freije, M.S.N. Graduate Adviser College of Nursing The PennsylvaniaPh.D. in Nursing B.S. to Ph.D. · M.S. to Ph.D. Dual-title Ph.D. (Nursing and Bioethics) Become a part of Penn State's vibrant research enterprise in nursing science Partner with nationally renowned

  16. Development of in situ CO2 and pH sensor for AUVs and ROVs

    NASA Astrophysics Data System (ADS)

    Nakano, Yoshiyuki; Kimoto, Hideshi; Miwa, Tetsuya; Yoshida, Hiroshi

    2013-04-01

    Japan Agency for Marine-Earth Science and Technology (JAMSTEC) has been developing two-type autonomous underwater vehicles (AUVs): a cruising AUV and a working AUV, since October 2010. These vehicles will perform carbon dioxide (CO2) and pH observations to explore hydrothermal plume on seabed mineral resources and to monitor a leak of CO2 in carbon capture and storage (CCS) up to depth of 3,000 meters. We here have been developing the compact in situ CO2 and pH sensor (Hybrid CO2-pH sensor: HCS) for the AUVs to obtain vertical and horizontal distributions of CO2 and pH. The HCS consists of an aluminum pressure housing (diameter 84 mm, length 570 mm, weight 4 kg) and an acrylic silicon-oil filled, pressure-compensated vessel (diameter 90 mm, length 355 mm, weight 2 kg) containing valves and pump unit. The HCS is also useful for the observation by remotely operated vehicles (ROVs). The measured data were transmitted to the AUVs or ROVs by serial communications. We can monitor the data of in situ pCO2, pH and so on in real time on board. The measurement principle for the CO2 sensor is based on spectrophotometry. The pCO2 is calculated from the optical absorbance of the pH indicator solution equilibrated with CO2 in seawater through a gas permeable membrane. On the other hand, we adopt potentiometric analysis using original glass and reference electrodes as a pH sensor because of the most commonly used technique for sea water pH measurements and high-speed response (within 20 seconds). From simultaneously measured data of in situ pCO2 and pH, we can also calculate dissolved inorganic carbon (DIC) and total alkalinity (TA) as other carbonate species in the ocean. The resolutions of HCS are 1 ?atm for pCO2 and 0.001 pH. In the laboratory experiment, the HCS obtained precisions within 3 ?atm and within 0.01 pH, respectively. Our first in situ observational test of the HSC with cruising AUV was made in the coast of the Japan Sea last August. And also first in situ test of the HCS with ROV was performed at Okinawa Trough last September. The data obtained from each tests are consistent with predictions based on past studies.

  17. Residence Time, Loading Force, pH, and Ionic Strength Affect Adhesion Forces between Colloids and

    E-print Network

    Residence Time, Loading Force, pH, and Ionic Strength Affect Adhesion Forces between Colloids strength (100 mM), consistent with previous AFM findings. These results show the importance of polymers An understanding of the chemical and physical factors influencing bacterial adhesion is important to bioreme

  18. Hans Peter Schwefel Wireless Networks III, Fall 2005: MM2, Wireless TCP

    E-print Network

    Schwefel, Hans-Peter

    III: advanced concepts Hans-Peter Schwefel and Tatiana K. Madsen hps@kom.auc.dk tatiana@kom.auc.dk http://www.kom.auc.dk/~hps http://www.kom.auc.dk/~tatiana · Mm1 IP Mobility Support (HPS) · Mm2 Wireless TCP (HPS) · Mm3 Wireless applications, SIP & IMS (HPS) · Mm4 Ad-hoc Networks I (TKM) · Mm5 Ad

  19. Administration Donald B. Thomason, PhD

    E-print Network

    Cui, Yan

    , PhD Director, Pharmacology Edwards Park, PhD Director, Laboratory Research & Management Leonard Lothstein, PhD Director, Nursing Science Carolyn Graff, PhD, RN Director, Pharmaceutical Sciences Duane D, Pharmaceutical Sciences, and Speech and Hearing Science. The college is located on the Health Science Center

  20. Radka Stoyanova, PhD

    Cancer.gov

    Dr. Radka Stoyanova, PhD has extensive background in developing approaches to best utilize imaging techniques in cancer research, diagnosis and treatment, as well as in developing approaches for the analysis, mining, and interpretation of "big data" generated by high-throughput approaches such as genomics, proteomics, and metabolomics. She received her Masters Degree in Mathematics from the University of Sofia, Bulgaria. Dr. Stoyanova obtained her doctoral training and PhD degree at the Imperial College London, under the mentorship of Profs.

  1. pH Meter Calibration

    NSDL National Science Digital Library

    The North Carolina Community College System BioNetwork's interactive eLearning tools (IETs) are reusable chunks of training that can be deployed in a variety of courses or training programs. IETs are designed to enhance, not replace hands-on training. Learners are able to enter a hands-on lab experience better prepared and more confident. This particular IET delves into pH Meter Calibration, where visitors practice performing a three point calibration of a pH meter using buffer solutions.

  2. Dosimetric study of the 15 mm ROPES eye plaque

    SciTech Connect

    Granero, D.; Perez-Calatayud, J.; Ballester, F.; Casal, E.; Frutos, J.M. de [Department of Atomic, Molecular and Nuclear Physics and IFIC, University of Valencia-CSIC, Dr. Moliner 50, E46100 Burjassot (Spain); Medical Physics Section, University Hospital, Av. Ramon y Cajal 3, E47011 Valladolid (Spain)

    2004-12-01

    The main aim of this paper is to make a study of dose-rate distributions obtained around the 15 mm, radiation oncology physics and engineering services, Australia (ROPES) eye plaque loaded with {sup 125}I model 6711 radioactive seeds. In this study, we have carried out a comparison of the dose-rate distributions obtained by the algorithm used by the Plaque Simulator (PS) (BEBIG GmbH, Berlin, Germany) treatment planning system with those obtained by means of the Monte Carlo method for the ROPES eye plaque. A simple method to obtain the dose-rate distributions in a treatment planning system via the superposition of the dose-rate distributions of a seed placed in the eye plaque has been developed. The method uses eye plaque located in a simplified geometry of the head anatomy and distributions obtained by means of the Monte Carlo code GEANT4. The favorable results obtained in the development of this method suggest that it could be implemented on a treatment planning system to improve dose-rate calculations. We have also found that the dose-rate falls sharply along the eye and that outside the eye the dose-rate is very low. Furthermore, the lack of backscatter photons from the air located outside the eye-head phantom produces a dose reduction negligible for distances from the eye-plaque r<1 cm but reaches up to 20% near the air-eye interface. Results showed that the treatment planning system lacks accuracy around the border of the eye (in the sclera and the surrounding area) due to the simplicity of the algorithm used. The BEBIG treatment planning system uses a global attenuation factor that takes into account the effect of the eye plaque seed carrier and the lack of backscatter photons caused by the metallic cover, which in the case of a ROPES eye plaque has a default value of T=1 (no correction). In the present study, a global attenuation factor T=0.96 and an air-interface correction factor which improve on treatment planning system calculations were obtained.

  3. Effects of pH and ionic strength on the potassium system in the internally perfused giant barnacle muscle fibre.

    PubMed

    Lakshminarayanaiah, N; Rojas, E

    1975-08-12

    Membrane potentials in single barnacle muscle fibres of Megabalanus psittacus, internally perfused with 200 mM K-acetate (KAc) solution of pH 7.5 were in the range --53 to --60 mV. These were followed as a function of pH of the external chloride saline. Decrease of pH of the Cl-saline from 8.5 to 3.5 hyperpolarized the membrane reversibly by about 8 mV. On further decrease of pH to 3.0, a transient hyperpolarization (from --60 to --65 mV) followed by a sudden and irreversible drop of potential to --40 mV was observed. Replacement of the external Cl-saline by acetate saline in the pH range 8.5 to 6.5 had no effect on the membrane potential. Further decrease of pH to 5.0 brought about an irreversible reduction of membrane potential. For fibres bathing in Cl- or Ac-saline at pH 7.5 when the internal pH was changed to 5.5, a transient hyperpolarization in Cl-saline and a sustained hyperpolarization in Ac-saline were observed. Further studies of membrane potential changing the concentration of external K, keeping the concentration of Cl or Ac constant, and changing the concentration of Cl or Ac, keeping the concentration of K constant, at different internal and external pHs showed that as the pH was reduced the membrane became more permeable to anions, Cl being more permeable than Ac. Experiments in which the membrane potential was controlled showed that when the internal pH of 200 mM KAc solution was reduced from 7.5 to 6.5 or raised to 8.5, the changes in outward K currents at various depolarizations were negligible. However, when the pH was reduced to 5.5 or 5.0, there was a progressive decrease in the outward K currents. The leakage currents in all these cases were relatively small. Use of high ionic strength solution of 580 mM KAc internally protected the K system in that when the pH was lowered the depression of the outward K current was smaller than that observed at a corresponding pH when the internal solution was 200 mM KAc. Use of low ionic strength solution of 50 mM KAc had the opposite effect. The results have been explained in terms of the ion exchange theory by postulating that the membrane has fixed amphoteric groups. PMID:241051

  4. Stress Analysis on Single Cobalt/Chrome Prosthesis with a 15mm Cantilever placed over 10/13/15mm length implants. A simulated photoelastic model study.

    PubMed

    Gastaldo, José Fábio Guastelli; Pimentel, Angelica Castro; Gomes, Maria Helena; Sendyk, Wilson Roberto; Lagana, Dalva Cruz

    2014-06-10

    Abstract Purpose: The aim of study was to assess the stress around 10/13/15 mm implants in the mandibular area with a 15 mm cantilevered acrylic resin coated prostheses following the application force, using the photoelasticity method. Materials and Methods: Three photoelastic mandibular models were created containing 10, 13, and 15 mm implants in length and 3.75 mm in diameter. The implants had bore internal hex connections and were placed parallel to the inter-mental region. Abutments with 1-mm high cuffs were placed over the implants, and a single cobalt/chrome metallic prosthesis with a 15-mm cantilever coated with thermoplastic acrylic resin was placed on top. Loads of 1.0 and 3.0 bars were applied, and the images were photographed and assessed by photoelasticity method. Results: The greatest stress levels were observed for the 10-mm implants. The stress pattern was the same regardless of the length of the implants; only the magnitude of the stress along the implant body revealed changes. Increased implant length played a role in reducing the stress on the investigated area of the model, and the 15-mm implants exhibited the best performance in regard to stress distribution. The highest stress levels were found in the implants closest to the cantilever and the central implant. Conclusions: The longest implants were more favorable in regard to the stress distribution on the peri-implant support structures in 15mm cantilevered prosthesis under loads. PMID:24914673

  5. Sashwati Roy, PhD

    Cancer.gov

    Dr. Sashwati Roy is an Associate Professor of Surgery and Director of the Laser Capture Molecular Core at The Ohio State University, Columbus, Ohio. In 1994 she received her PhD degree in Physiology and Environmental Sciences and later completed her postdoctoral training at the University of California, Berkeley. Dr.

  6. Karl Krueger, PhD

    Cancer.gov

    Dr. Karl Krueger received a PhD in biochemistry from Vanderbilt University and continued his research training at NIH as a postdoctoral fellow before joining the faculty at Georgetown University School of Medicine. His research throughout this period focused on different aspects of drug receptors and their role in the nervous system.

  7. Intracellular pH changes induced by calcium influx during electrical activity in molluscan neurons

    PubMed Central

    1980-01-01

    Simultaneous measurements of electrical activity and light absorbance have been made on nerve cell bodies from Archidoris monteryensis injected with indicator dyes. pH indicators, phenol red and bromocresol purple, and arsenazo III, which under normal conditions is primarily a calcium indicator have been employed. Voltage clamp pulses which induced calcium influx caused an absorbance decrease of the pH dyes indicating an internal acidification. The onset of the pH drop lagged the onset of Ca2+ influx by 200-400 ms, and pH continued to decrease for several seconds after pulse termination which shut off Ca2+ influx. Trains of action potentials also produced an internal pH decrease. Recovery of the pH change required periods greater than 10 min. The magnitude of the pH change was largely unaffected by external pH in the range 6.8-8.4. The voltage dependence of the internal p/ change was similar to the voltage dependence of calcium influx determined by arsenazo III, and removal of calcium from the bathing saline eliminated the pH signal. In neurons injected with EGTA (1-5 mM), the activity- induced internal Ca2+ changes were reduced or eliminated, but the internal pH drop was increased severalfold in magnitude. After the injection of EGTA, voltage clamp pulses produced a decrease in arsenazo III absorbance instead of the normal increase. Under these conditions the dye was responding primarily to changes in internal pH. Injection of H+ caused a rise in internal free calcium. The pH buffering capacity of the neurons was measured using three different techniques: H+ injection, depressing intrinsic pH changes with a pH buffer, and a method employing the EGTA-calcium reaction. The first two methods gave similar measurements: 4-9 meq/unit pH per liter for pleural ganglion cells and 13-26 meq/unit pH per liter for pedal ganglion cells. The EGTA method gave significantly higher values (20-60 meq/unit pH per liter) and showed no difference between pleural and pedal neurons. PMID:7381426

  8. The influence of calcium and pH on growth in primary roots of Zea mays

    NASA Technical Reports Server (NTRS)

    Hasenstein, K. H.; Evans, M. L.

    1988-01-01

    We investigated the interaction of Ca2+ and pH on root elongation in Zea mays L. cv. B73 x Missouri 17 and cv. Merit. Seedlings were raised to contain high levels of Ca2+ (HC, imbibed and raised in 10 mM CaCl2) or low levels of Ca2+ (LC, imbibed and raised in distilled water). In HC roots, lowering the pH (5 mM MES/Tris) from 6.5 to 4.5 resulted in strong, long-lasting growth promotion. Surprisingly, increasing the pH from 6.5 to 8.5 also resulted in strong growth promotion. In LC roots acidification of the medium (pH 6.5 to 4.5) resulted in transient growth stimulation followed by a gradual decline in the growth rate toward zero. Exposure of LC roots to high pH (pH shift from 6.5 to 8.5) also promoted growth. Addition of EGTA resulted in strong growth promotion in both LC and HC roots. The ability of EGTA to stimulate growth appeared not to be related to H+ release from EGTA upon Ca2+ chelation since, 1) LC roots showed a strong and prolonged response to EGTA, but only a transient response to acid pH, and 2) promotion of growth by EGTA was observed in strongly buffered solutions. We also examined the pH dependence of the release of 45Ca2+ from roots of 3-day-old seedlings grown from grains imbibed in 45Ca2+. Release of 45Ca2+ from the root into agar blocks placed on the root surface was greater the more acidic the pH of the blocks. The results indicate that Ca2+ may be necessary for the acid growth response in roots.

  9. Experimentally and theoretically observed native pH shifts in a nanochannel array.

    PubMed

    Bottenus, Danny; Oh, Youn-Jin; Han, Sang M; Ivory, Cornelius F

    2009-01-21

    Lab-on-a-chip (LOC) technology provides a powerful platform for simultaneous separation, purification, and identification of low concentration multicomponent mixtures. As the characteristic dimension of LOC devices decreases down to the nanoscale, the possibility of containing an entire lab on a single chip is becoming a reality. This research examines one of the unique physical characteristics of nanochannels, in which native pH shifts occur. As a result of the electrical double layer taking up a significant portion of a 100 nm wide nanochannel, electroneutrality no longer exists in the channel causing a radial pH gradient. This work describes experimentally observed pH shifts as a function of ionic strength using the fluorescent pH indicator 5-(and-6)-carboxy SNARF-1 and compares it to a model developed using Comsol Multiphysics. At low ionic strengths (approximately 3 mM) the mean pH shift is approximately 1 pH unit whereas at high ionic strengths (approximately 150 mM) the mean pH shift is reduced to 0.1 pH units. An independent analysis using fluorescein pH indicator is also presented supporting these findings. Two independent non-linear simulations coupling the Nernst-Planck equation describing transport in ionic solutions subjected to an electric field and Poisson's equation to describe the electric field as it relates to the charge distribution are solved using a finite element solver. In addition, the effects of chemical activities are considered in the simulations. The first numerical simulation is based on a surface zeta-potential which significantly underestimates the experimental results for most ionic strengths. A modified model assuming that SNARF and fluorescein molecules are able to diffuse into the hydrolyzed SiO2 phase, and in the case of the SNARF molecule, able to bind to neutral regions of the SiO2 phase agrees quantitatively with experimental results. PMID:19107277

  10. Stabilization of pH in solid-matrix hydroponic systems

    NASA Technical Reports Server (NTRS)

    Frick, J.; Mitchell, C. A.

    1993-01-01

    2-[N-morpholino]ethanesulfonic acid (MES) buffer or Amberlite DP-1 (cation-exchange resin beads) were used to stabilize substrate pH of passive-wicking, solid-matrix hydroponic systems in which small canopies of Brassica napus L. (CrGC 5-2, genome : ACaacc) were grown to maturity. Two concentrations of MES (5 or 10 mM) were included in Hoagland 1 nutrient solution. Alternatively, resin beads were incorporated into the 2 vermiculite : 1 perlite (v/v) growth medium at 6% or 12% of total substrate volume. Both strategies stabilized pH without toxic side effects on plants. Average seed yield rates for all four pH stabilization treatments (13.3 to 16.9 g m-2 day-1) were about double that of the control (8.2 g m-2 day-1), for which there was no attempt to buffer substrate pH. Both the highest canopy seed yield rate (16.9 g m-2 day-1) and the highest shoot harvest index (19.5%) occurred with the 6% resin bead treatment, even though the 10 mM MES and 12% bead treatments maintained pH within the narrowest limits. The pH stabilization methods tested did not significantly affect seed oil and protein contents.

  11. Changes in extra- and intracellular pH in hepatocytes exposed to gabexate mesilate.

    PubMed

    Imberti, R; Ferrigno, A; Tartaglia, A; Rizzo, V; Richelmi, P; Vairetti, M

    2014-01-01

    Gabexate mesilate (GM) is a synthetic inhibitor of plasmatic and pancreatic serine proteases licensed for the treatment of pancreatitis. Here we show that in suspensions of isolated hepatocytes, profound changes in extracellular, cytoplasmic, and vesicular pH occur after addition of GM. Isolated hepatocytes obtained by collagenase perfusion of rat liver were pre-incubated with 1, 2, and 4 mM GM. Extracellular pH (pH in the incubation medium) was measured by a conventional pH electrode, cytosolic and vesicular pH were measured by fluorescence changes of 2',7'-biscarboxyethyl-5,6-carboxyfluorescein acetoxymethyl ester (BCECF-AM) and fluorescein dextran, respectively. Incubation of hepatocytes with GM resulted in a dose-dependent decrease of extracellular pH. Cytosolic pH decreased rapidly and markedly in a dose-dependent manner during the first minutes and gradually returned towards baseline. Simultaneously, GM induced a rapid alkalinization of acidic vesicles. The presence of bis-(p-nitrophelyl) phosphate (BNPP), an esterase inhibitor, reduced the extent of extracellular acidification. Incubation of hepatocytes in the presence of dimethylamiloride, an Na+/H+ exchanger inhibitor, or in a sodium-free medium, did not modify the rate and extent of extracellular acidification. GM, a commercially available pharmacological agent, could be useful to manipulate extra- and intracellular pH. PMID:25280027

  12. Comparison of Surgically-induced Astigmatism after Combined Phacoemulsification and 23-Gauge Vitrectomy: 2.2-mm vs. 2.75-mm Cataract Surgery

    PubMed Central

    Kim, Yong-Kyu; Kim, Yong Woo; Park, Kyu Hyung

    2014-01-01

    Purpose The 2.2-mm microincision cataract surgery and small-gauge vitrectomy system is known to result in less surgically-induced astigmatism (SIA) in comparison to conventional surgical methods. We compared the amounts of SIA after combined phacoemulsification and 23-gauge transconjunctival sutureless vitrectomy (23G-TSV) using the 2.2-mm microincision and 2.75-mm standard incision methods. Methods We studied 59 patients (61 eyes) who underwent combined phacoemulsification and 23G-TSV from November 2008 to September 2012. Twenty-eight patients (28 eyes) underwent 2.2-mm microincision coaxial phacoemulsification, and 31 patients (33 eyes) underwent 2.75-mm standard incision phacoemulsification. SIA was evaluated using Naeser's polar method with the simulated keratometric values obtained from corneal topography. Preoperative and 1-week and 1-month postoperative KP (Naeser's polar value along the specific axis) and ?KP values were compared between the 2.2-mm microincision and 2.75-mm standard incision groups. Results One week after surgery, both groups exhibited similar amounts of SIA (-?KP[120], 0.40 ± 0.41 vs. 0.51 ± 0.56 diopters [D]; p = 0.390). One month after surgery, however, the amount of SIA was significantly smaller in the 2.2-mm microincision group as compared to the 2.75-mm standard incision group (-?KP[120], 0.31 ± 0.54 vs. 0.56 ± 0.42 D; p = 0.045). Conclusions In combined phacoemulsification with 23G-TSV, 2.2-mm microincision coaxial phacoemulsification induces less SIA than does 2.75-mm standard coaxial phacoemulsification. PMID:24688255

  13. Draft Genomes of Heterogeneous Vancomycin-Intermediate Staphylococcus aureus Strain MM66 and MM66 Derivatives with Altered Vancomycin Resistance Levels

    PubMed Central

    Matyi, Stephanie A.; Ramaraj, Thiruvarangan; Sundararajan, Anitha; Lindquist, Ingrid E.; Devitt, Nicolas P.; Schilkey, Faye D.; Lamichhane-Khadka, Reena; Hoyt, Peter R.; Mudge, Joann

    2014-01-01

    The draft genomes of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) strain MM66 and MM66 isolates demonstrating altered vancomycin resistance levels were produced in an effort to provide information on mutations contributing to the vancomycin resistance levels observed in these strains. PMID:25013145

  14. Heat Transfer -2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature

    E-print Network

    Virginia Tech

    Heat Transfer - 2 A pure platinum wire with diameter D = 3 mm and length L = 20 mm is placed outside on a day when air temperature T = 10o C. The heat transfer coefficient at the wire's surface h equation that includes all heat transfer mechanisms involved in this problem. Write this energy balance

  15. A Polarizable QM/MM Explicit Solvent Model for Computational Electrochemistry in Water

    E-print Network

    Wang, Lee-Ping

    We present a quantum mechanical/molecular mechanical (QM/MM) explicit solvent model for the computation of standard reduction potentials E[subscript 0]. The QM/MM model uses density functional theory (DFT) to model the ...

  16. Gastric pH and motility in a porcine model of acute lung injury using a wireless motility capsule

    PubMed Central

    Rauch, Stefan; Muellenbach, Ralf M.; Johannes, Amélie; Zollhöfer, Bernd; Roewer, Norbert

    2011-01-01

    Summary Background Evaluation of gastric pH and motility in a porcine model of acute lung injury using a novel, wireless motility capsule. Material/Methods A motility capsule was applied into the stomach of 7 Pietrain pigs with acute lung injury induced by high volume saline lavage. Wireless transmission of pH, pressure and temperature data was performed by a recorder attached to the animal’s abdomen. Gastric motility was evaluated using pH and pressure values, and capsule location was confirmed by autopsy. Results Gastric pH values were statistically significantly different (P<0.003) in the animals over time and ranged from 1.15 to 9.94 [5.73±0.47 (mean ±SD)] with an interquartile range of 0.11 to 2.07. The capsule pressure recordings ranged from 2 to 4 mmHg [2.6±0.5 mmHg (mean ±SD)]. There was no change in pressure patterns or sudden rise of pH >3 pH units during 24 hours. All animals had a gastroparesis with the capsules located in the stomach as indicated by the pressure and pH data and confirmed by necropsy. Conclusions The preliminary data show that Pietrain pigs with acute lung injury have a high variability in gastric pH and severely disturbed gastric motility. PMID:21709625

  17. Yeast Genomic DNA Preparation from Spheroplasts 1. Resuspend with 50 mM Tris, 25 mM EDTA (pH 8) in 10X the spheroplast pellet volume.

    E-print Network

    Aris, John P.

    minutes in SS-34 rotor at 10,000 rpm at 4°C. Discard supernatant. 10. Wash with 70% ethanol. Gently break,000 rpm at 4°C. Discard supernatant. 12. Drain and dry pellets on bench. Dissolve each pellet completely in SS-34 rotor at 10,000 rpm at 4°C. Discard supernatant. 17. Wash with 70% EtOH (several mls). Disperse

  18. Experimental characterization and system simulations of depth of interaction PET detectors using 0.5 mm and 0.7 mm LSO arrays

    PubMed Central

    James, Sara St.; Yang, Yongfeng; Wu, Yibao; Farrell, Richard; Dokhale, Purushottam; Shah, Kanai S.; Cherry, Simon R.

    2009-01-01

    Small animal PET scanners may be improved by increasing the sensitivity, improving the spatial resolution and improving the uniformity of the spatial resolution across the field of view. This may be achieved by using PET detectors based on crystal elements that are thin in the axial and transaxial directions and long in the radial direction, and by employing depth of interaction (DOI) encoding to minimize the parallax error. With DOI detectors, the diameter of the ring of the PET scanner may also be decreased. This minimizes the number of detectors required to achieve the same solid angle coverage as a scanner with a larger ring diameter and minimizes errors due to non-collinearity of the annihilation photons. In this study, we characterize prototype PET detectors that are finely pixelated with individual LSO crystal element sizes of 0.5 mm × 0.5 mm × 20 mm and 0.7 mm × 0.7 mm × 20 mm, read out at both ends by position sensitive avalanche photodiodes (PSAPDs). Both a specular reflector and a diffuse reflector were evaluated. The detectors were characterized based on the ability to clearly resolve the individual crystal elements, the DOI resolution and the energy resolution. Our results indicate that a scanner based on any of the four detector designs would offer improved spatial resolution and more uniform spatial resolution compared to present day small animal PET scanners. The greatest improvements to spatial resolution will be achieved when the detectors employing the 0.5 mm × 0.5 mm × 20 mm crystals are used. Monte Carlo simulations were performed to demonstrate that 2 mm DOI resolution is adequate to ensure uniform spatial resolution for a small animal PET scanner geometry using these detectors. The sensitivity of such a scanner was also simulated using Monte Carlo simulations and was shown to be greater than 10 % for a four ring scanner with an inner diameter of 6 cm, employing 20 detectors per scanner ring. PMID:19567945

  19. Compact mission configurable mm-wave spectrometer based on a channel drop filter

    Microsoft Academic Search

    Evgenya I. Smirnova; Aimee G. Bailey; Lawrence M. Earley; Sergey S. Kurennoy

    2007-01-01

    We have developed a novel mm-wave spectrometer based on a Photonic Band Gap (PBG) channel-drop filter (CDF). There is a need for a compact wide-band versatile and configurable mm-wave spectrometer for applications in mm-wave communications and remote sensing. CDFs present us with a unique means for filtering frequencies at mm-waves. CDF is a novel concept allowing filtering the frequency spectra

  20. pH Wave-Front Propagation in the Urea-Urease Reaction

    PubMed Central

    Wrobel, Magdalena M.; Bánsági, Tamás; Scott, Stephen K.; Taylor, Annette F.; Bounds, Chris O.; Carranza, Arturo; Pojman, John A.

    2012-01-01

    The urease-catalyzed hydrolysis of urea displays feedback that results in a switch from acid (pH ?3) to base (pH ?9) after a controllable period of time (from 10 to >5000 s). Here we show that the spatially distributed reaction can support pH wave fronts propagating with a speed of the order of 0.1?1 mm min?1. The experimental results were reproduced qualitatively in reaction-diffusion simulations including a Michaelis-Menten expression for the urease reaction with a bell-shaped rate-pH dependence. However, this model fails to predict that at lower enzyme concentrations, the unstirred reaction does not always support fronts when the well-stirred reaction still rapidly switches to high pH. PMID:22947878

  1. REMARQUES SUR LE TRAVAIL DE MM. NAGAOKA ET HONDA ; Par M. CH.-D. GUILLAUME

    E-print Network

    Paris-Sud XI, Université de

    633 REMARQUES SUR LE TRAVAIL DE MM. NAGAOKA ET HONDA ; Par M. CH.-�D. GUILLAUME Les recherches de MM. Nagaolia et Honda sur la inagnéto- striction donnent lieu à deux genres de remarques : les unes que pour une proportion insignifiante dans les résultats énoncés par MM. Nagaoka et Honda, et que les

  2. Stella Koutros, Ph.D.

    Cancer.gov

    Dr. Koutros received her M.P.H. and Ph.D. in epidemiology from Yale University. She completed her doctoral work through the Yale-NCI partnership training program in cancer epidemiology, conducting research in the Occupational and Environmental Epidemiology Branch (OEEB). In 2008, upon completion of her doctorate she became a fellow in OEEB; she was appointed to the position of tenure-track investigator in 2015.

  3. Christos Patriotis, PhD

    Cancer.gov

    Dr. Christos Patriotis obtained his MSc in Biochemistry from the University of Sofia, Bulgaria in 1985 and his PhD in Molecular Biology from the Bulgarian Academy of Sciences in 1990. Postdoctoral training focused on signal transduction and tumor cell biology. He joined the faculty at Fox Chase Cancer Center in 1998; his research was directed toward understanding mechanisms of breast and ovarian cancer pathogenesis and identification of biomarkers associated with the early stages of the two types of cancer.

  4. Richard Mazurchuk, PhD

    Cancer.gov

    Dr. Richard Mazurchuk received a BS in Physics and MS and PhD in Biophysics from SUNY Buffalo. His research focused on developing novel multi-modality imaging techniques, contrast (enhancing) agents and methods to assess the efficacy of experimental therapeutics. He subsequently joined the faculty of SUNY Buffalo School of Medicine and Roswell Park Cancer Institute attaining the rank of Assoc Prof in the Departments of Diagnostic Imaging and Molecular and Cellular Biochemistry and Biophysics.

  5. PhET: The Ramp

    NSDL National Science Digital Library

    In this simulation, students push common items of varying masses up an incline to explore the relationship of applied force, work, and energy. They control the angle of the ramp, friction, and amount of applied force. With a mouse click, they can also view detailed graphs of work and energy. This item is part of a larger collection of simulations developed by the Physics Education Technology project (PhET). The simulations are animated, interactive, and game-like environments.

  6. The pH of antiseptic cleansers

    PubMed Central

    Kulthanan, Kanokvalai; Varothai, Supenya; Nuchkull, Piyavadee

    2014-01-01

    Background Daily bathing with antiseptic cleansers are proposed by some physicians as an adjunctive management of atopic dermatitis (AD). As atopic skin is sensitive, selection of cleansing products becomes a topic of concern. Objective Our purpose is to evaluate the pH of various antiseptic body cleansers to give an overview for recommendation to patients with AD. Methods Commonly bar and liquid cleansers consisted of antiseptic agents were measured for pH using pH meter and pH-indicator strips. For comparison, mild cleansers and general body cleansers were also measured. Results All cleansing bars had pH 9.8-11.3 except syndet bar that had neutral pH. For liquid cleansers, three cleansing agents had pH close to pH of normal skin, one of antiseptic cleansers, one of mild cleansers and another one of general cleansers. The rest of antiseptic cleansers had pH 8.9-9.6 while mild cleansers had pH 6.9-7.5. Syndet liquid had pH 7 and general liquid cleansers had pH 9.6. Conclusion The pH of cleanser depends on composition of that cleanser. Adding antiseptic agents are not the only factor determining variation of pH. Moreover, benefit of antiseptic properties should be considered especially in cases of infected skin lesions in the selection of proper cleansers for patients with AD. PMID:24527408

  7. SUBMILLIMETER ARRAY OBSERVATIONS TOWARD THE MASSIVE STAR-FORMING CORE MM1 OF W75N

    SciTech Connect

    Minh, Y. C. [Korea Astronomy and Space Science Institute (KASI), 838 Daeduk-daero, Hwaam, Yuseong-gu, Daejeon 305-348 (Korea, Republic of); Su, Y.-N.; Liu, S.-Y.; Yan, C.-H. [Academia Sinica, Institute of Astronomy and Astrophysics (ASIAA), P.O. Box 23-141, Taipei 106, Taiwan (China); Chen, H.-R. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Kim, S.-J., E-mail: minh@kasi.re.k [Department of Astronomy and Space Science, Kyunghee University, Yongin, Gyeonggi 446-701 (Korea, Republic of)

    2010-11-10

    The massive star-forming core MM1 of W75N was observed using the Submillimeter Array with {approx}1'' and 2'' spatial resolutions at 217 and 347 GHz, respectively. From the 217 GHz continuum we found that the MM1 core consists of two sources, separated by about 1'': MM1a ({approx}0.6 M{sub sun}) and MM1b ({approx}1.4 M{sub sun}), located near the radio continuum sources VLA 2/VLA 3 and VLA 1, respectively. Within MM1b, two gas clumps were found to be expanding away from VLA 1 at about {+-}3 km s{sup -1}, as a result of the most recent star formation activity in the region. Observed molecular lines show emission peaks at two positions, MM1a and MM1b: sulfur-bearing species have emission peaks toward MM1a, but methanol and saturated species at MM1b. We identified high-temperature ({approx}200 K) gas toward MM1a and the hot core in MM1b. This segregation may result from the evolution of the massive star-forming core. In the very early phase of star formation, the hot core is seen through the evaporation of dust ice-mantle species. As the mantle species are consumed via evaporation the high-temperature gas species (such as the sulfur-bearing molecules) become bright. The SiO molecule is unique in having an emission peak exactly at the VLA 2 position, probably tracing a shock powered by VLA 2. The observed sulfur-bearing species show similar abundances both in MM1a and MM1b, whereas the methanol and saturated species show significant abundance enhancement toward MM1b, by about an order of magnitude, compared to MM1a.

  8. Molecular dynamics simulations of ion solvation by flexible-boundary QM/MM: on-the-fly partial charge transfer between QM and MM subsystems.

    PubMed

    Pezeshki, Soroosh; Lin, Hai

    2014-09-15

    The flexible-boundary (FB) quantum mechanical/molecular mechanical (QM/MM) scheme accounts for partial charge transfer between the QM and MM subsystems. Previous calculations have demonstrated excellent performance of FB-QM/MM in geometry optimizations. This article reports an implementation to extend FB-QM/MM to molecular dynamics simulations. To prevent atoms from getting unreasonably close, which can lead to polarization catastrophe, empirical correcting functions are introduced to provide additive penalty energies for the involved atom pairs and to improve the descriptions of the repulsive exchange forces in FB-QM/MM calculations. Test calculations are carried out for chloride, lithium, sodium, and ammonium ions solvated in water. Comparisons with conventional QM/MM calculations suggest that the FB treatment provides reasonably good results for the charge distributions of the atoms in the QM subsystems and for the solvation shell structural properties, albeit smaller QM subsystems have been used in the FB-QM/MM dynamics simulations. PMID:25056247

  9. (August 29, 2014) Neuroscience Ph.D.

    E-print Network

    HANDBOOK (August 29, 2014) Neuroscience Ph.D. Program Daniel Tranel, PhD Program Director Michael ...................................................................................................4 B. Neuroscience Program Graduate Research Assistantships .................................5 C ......................................................................................................................7 A. Required Core Neuroscience Courses

  10. (November 20, 2014) Neuroscience Ph.D.

    E-print Network

    HANDBOOK (November 20, 2014) Neuroscience Ph.D. Program Daniel Tranel, PhD Program Director Michael ...................................................................................................4 B. Neuroscience Program Graduate Research Assistantships .................................5 C ......................................................................................................................7 A. Required Core Neuroscience Courses

  11. Coping with PH over the Long Term

    MedlinePLUS

    ... Young Adult Issues Dating and Relationships College and Scholarships Family Planning Considering Adoption with PH The Adoption ... Young Adult Issues Dating and Relationships College and Scholarships Family Planning Considering Adoption with PH The Adoption ...

  12. Repeatability of the efficiency of columns packed with sub-3?m core-shell particles: Part I. 2.6?m Kinetex-C(18) particles in 4.6mm and 2.1mm×100mm column formats.

    PubMed

    Gritti, Fabrice; Guiochon, Georges

    2012-08-24

    The column-to-column repeatability of the mass transfer mechanism in columns packed with sub-3?m shell particles was investigated. The parameters of this mechanism were measured for twelve columns (six 2.1mm×100mm and six 4.6mm×100mm) packed with the same batch of 2.6?m Kinetex-C(18) particles (Phenomenex, CA, USA). For both series, the manufacturer provided columns at different positions in the efficiency distribution given by the quality test control. Three compounds were used, uracil, naphthalene and insulin. The reduced longitudinal diffusion term was measured with the peak parking (PP) method, the reduced solid-liquid mass transfer resistance term was given by a combination of the PP results and a model of effective diffusion in ternary composite materials (non-porous cores, concentric porous shell, and eluent matrix), validated previously. The overall eddy diffusion term was obtained by subtraction of these two HETP terms from the overall reduced HETP measured by numerical integration of the entire peak profiles. The results demonstrate that the dispersion of the column efficiencies is only due to the random nature of the packing process. At the highest reduced velocity achieved, the relative standard deviations (RSDs) of the eddy diffusion term for the 2.1mm I.D. columns were ca. 7% and 3% for the low molecular weight compounds and for insulin, respectively. For the 4.6mm I.D. columns, these RSDs were 15% and 5%, respectively. The larger RSDs for the 4.6mm I.D. columns is explained by the exceptionally low value of the eddy diffusion term. PMID:22762953

  13. University College Dublin PhD Scholarships

    E-print Network

    University College Dublin PhD Scholarships UCD Michael Smurfit Graduate Business School invites excellent applications for a number of PhD scholarships starting in September 2014. This provides four years of support for full-time PhD study. The Scholarships are open to full-time EU and non-EU students

  14. Inexpensive and Disposable pH Electrodes

    ERIC Educational Resources Information Center

    Goldcamp, Michael J.; Conklin, Alfred; Nelson, Kimberly; Marchetti, Jessica; Brashear, Ryan; Epure, Emily

    2010-01-01

    Inexpensive electrodes for the measurement of pH have been constructed using the ionophore tribenzylamine for sensing H[superscript +] concentrations. Both traditional liquid-membrane electrodes and coated-wire electrodes have been constructed and studied, and both exhibit linear, nearly Nernstian responses to changes in pH. Measurements of pH…

  15. Influence of pH on persulfate oxidation of TCE at ambient temperatures.

    PubMed

    Liang, Chenju; Wang, Zih-Sin; Bruell, Clifford J

    2007-01-01

    In situ chemical oxidation (ISCO) is a technology used for groundwater remediation. This laboratory study investigated the use of the oxidant sodium persulfate for the chemical oxidation of trichloroethylene (TCE) at near ambient temperatures (10, 20 and 30 degrees C) to determine the influence of pH (pH=4, 7 and 9) on the reaction rate (i.e., pseudo-first-order rate constants) over the range of temperatures utilized. TCE solutions (60 mg l(-1); 0.46 mM) were prepared in phosphate buffered RO water and a fixed persulfate/TCE molar ratio of 50/1 was employed in all tests. Half-lives of TCE degradation at 10, 20 and 30 degrees C (pH 7) were 115.5, 35.0 and 5.5h, respectively. Maximum TCE degradation occurred at pH 7. Lowering system pH resulted in a greater decrease in TCE degradation rates than increasing system pH. Radical scavenging tests used to identify predominant radical species suggested that the sulfate radical (SO(4)(.-)) predominates under acidic conditions and the hydroxyl radical (.OH) predominates under basic conditions. In a side by side comparison of TCE degradation in a groundwater vs. unbuffered RO water it was demonstrated that when the system pH is buffered to near neutral pH conditions due to the presence of natural occurring groundwater constituents that the TCE degradation rate is higher than in unbuffered RO water where the system pH dropped from 5.9 to 2.8. The results of this study suggest that in a field application of ISCO, pH should be monitored and adjusted to near neutral if necessary. PMID:16814844

  16. Effects of pH on the ability of flavonoids to act as Pickering emulsion stabilizers.

    PubMed

    Luo, Zijun; Murray, Brent S; Ross, Anne-Lise; Povey, Malcolm J W; Morgan, Michael R A; Day, Andrea J

    2012-04-01

    The flavonoids tiliroside, rutin and naringin have been investigated as stabilizers of Pickering oil-in-water (O/W) emulsions. The mean droplet size of tetradecane emulsions was considerably smaller at higher pH, especially for rutin. The solubility of flavonoids in the aqueous phase was 4-6 times higher at pH 8 compared to pH 2 for tiliroside and rutin, although all absolute solubilities remained low (<1 mM). This agreed with a slight increase in surface activity of tiliroside and rutin at the O-W interface at pH 8 compared to pH 2. However, improved emulsion stabilization at higher pH is better explained by the significant increase in ?-potential of the flavonoid particles to more negative values at pH 8, which will improve particle dispersion and increase the charge on the droplets stabilized by them. A buckwheat tea extract, rich in rutin, was also shown to be an effective stabilizer of sunflower O/W emulsions. PMID:22197223

  17. Improved zinc oxide surge arresters using high voltage gradient 300 V\\/mm, 400 V\\/mm ZnO elements

    Microsoft Academic Search

    Shingo Shirakawa; Seiichi Yamada; Shigeru Tanaka; Iwao Ejiri; Satoshi Watahiki; Shinichi Kondo

    2000-01-01

    Zinc oxide surge arresters using zinc oxide (ZnO) elements have been widely used for insulation coordination in the world's power systems. These ZnO elements have basically reference voltage of about 200 V\\/mm. Recently, new ZnO elements having about 1.5, 2 times high voltage gradient zinc oxide element have been developed. This paper describes applications of high voltage gradient 300 V\\/mm

  18. Assessing the performance of the MM/PBSA and MM/GBSA methods: I. The accuracy of binding free energy calculations based on molecular dynamics simulations

    PubMed Central

    Hou, Tingjun; Wang, Junmei; Li, Youyong; Wang, Wei

    2011-01-01

    The Molecular Mechanics/Poisson Boltzmann Surface Area (MM/PBSA) and the Molecular Mechanics/Generalized Born Surface Area (MM/GBSA) methods calculate binding free energies for macromolecules by combining molecular mechanics calculations and continuum solvation models. To systematically evaluate the performance of these methods, we report here an extensive study of 59 ligands interacting with six different proteins. First, we explored the effects of the length of the molecular dynamics (MD) simulation, ranging from 400 to 4800 ps, and the solute dielectric constant (1, 2 or 4) to the binding free energies predicted by MM/PBSA. The following three important conclusions could be observed: (1). MD simulation lengths have obvious impact on the predictions, and longer MD simulations are not always necessary to achieve better predictions; (2). The predictions are quite sensitive to solute dielectric constant, and this parameter should be carefully determined according to the characteristics of the protein/ligand binding interface; (3). Conformational entropy showed large fluctuations in MD trajectories and a large number of snapshots are necessary to achieve stable predictions. Next, we evaluated the accuracy of the binding free energies calculated by three Generalized Born (GB) models. We found that the GB model developed by Onufriev and Case was the most successful model in ranking the binding affinities of the studied inhibitors. Finally, we evaluated the performance of MM/GBSA and MM/PBSA in predicting binding free energies. Our results showed that MM/PBSA performed better in calculating absolute, but not necessarily relative, binding free energies than MM/GBSA. Considering its computational efficiency, MM/GBSA can serve as a powerful tool in drug design, where correct ranking of inhibitors is often emphasized. PMID:21117705

  19. Rainwater ph in the vicinity of hadera power plant, Israel during the winter season of 1981/82

    NASA Astrophysics Data System (ADS)

    Kolton-Shapira, Rivka; Lakritz, Yerucham; Luria, Menachem

    A new method for the continuous pH measurement of rainwater is discussed. Tkis method, applied at a site near a new coal-fired power plant (before its operation), showed a pH variation of 4.3 to 9.2 as compared to 6.5 ± 1.0 observed using conventional methods which measure pH at the end of each rain episode. The alkalinity of top soil in the vicinity, and hence natural aerosols act as a buffer, reducing the acidity of the rain. This buffering effect disappears after 30-40 mm of rainfall.

  20. Soil pH and Fertilizers

    NSDL National Science Digital Library

    This Web site by the Mississippi State University Extension Service discusses why fertilizers are added to soils. The Web site begins by introducing the concept of the pH of the soil and how nutrients are affected by this pH level. Students can then learn about the pH logarithmic scale and about the factors that affect soil pH. At the end of the site, users will find a clear and concise table concerning different fertilizer materials characteristics including their speed of reaction and effect on pH in soils.

  1. Soils - Part 4: Soil pH

    NSDL National Science Digital Library

    Soil pH is defined and its implications for crop production are described in this lesson. How are soil pH and buffer pH determined? How are these assessments used in lime recommendations? The factors that influence pH variations in soils, the chemistry involved in changing the pH of a soil, and the benefits associated with liming acid soils will be discussed.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

  2. Kinetic evidence for the interactive inhibition of laccase from Trametes versicolor by pH and chloride.

    PubMed

    Raseda, Nasrin; Hong, Soonho; Kwon, O Yul; Ryu, Keungarp

    2014-12-28

    The interactive inhibitory effects of pH and chloride on the catalysis of laccase from Trametes versicolor were investigated by studying the alteration of inhibition characteristics of sodium chloride at different pHs for the oxidation of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid). At pH 3.0, the addition of sodium chloride (50 mM) brought about a 40-fold increase in Km(app) and a 4-fold decrease in Vmax(app). As the pH increased to 7.0, the inhibitory effects of sodium chloride became significantly weakened. The mixed-inhibition mechanism was successfully used to quantitatively estimate the competitive and uncompetitive inhibition strengths by chloride at two different pHs (pH 3.0 and 6.0). At pH 3.0, the competitive inhibition constant, Ki, was 0.35 mM, whereas the uncompetitive inhibition constant, Ki', was 18.1 mM, indicating that the major cause of the laccase inhibition by chloride is due to the competitive inhibition step. At a higher pH of 6.0, where the inhibition of the laccase by hydroxide ions takes effect, the inhibition of the laccase by chloride diminished to a great extent, showing increased values of both the competitive inhibition constant (Ki= 23.7 mM) and uncompetitive inhibition constant (Ki' = 324 mM). These kinetic results evidenced that the hydroxide anion and chloride share a common mechanism to inhibit the laccase activity. PMID:25152059

  3. Cyclic variations in nitrogen uptake rate of soybean plants: effects of pH and mixed nitrogen sources

    NASA Technical Reports Server (NTRS)

    Raper, C. D. Jr; Vessey, J. K.; Henry, L. T.; Chaillou, S.

    1991-01-01

    To determine if the daily pattern of NO3- and NH4+ uptake is affected by acidity or NO3- : NH4+ ratio of the nutrient solution, non-nodulated soybean plants (Glycine max) were exposed for 21 days to replenished, complete nutrient solutions at pH 6.0, 5.5, 5.0, and 4.5 which contained either 1.0 mM NH4+, 1.0 mM NO3- [correction of NO3+], 0.67 mM NH4+ plus 0.33 mM NO3- (2:1 NH4+ : NO3-) [correction of (2:1 NH3+ : NO4-)], or 0.33 mM NH4+ plus 0.67 mM NO3- (1:2 NH4+ : NO3-). Net uptake rates of NH4+ and NO3- were measured daily by ion chromatography as depletion from the replenished solutions. When NH4+ and NO3- were supplied together, cumulative uptake of total nitrogen was not affected by pH or solution NH4+ : NO3- ratio. The cumulative proportion of nitrogen absorbed as NH4+ decreased with increasing acidity; however, the proportional uptake of NH4+ and NO3- was not constant, but varied day-to-day. This day-to-day variation in relative proportions of NH4+ and NO3- absorbed when NH4+ : NO3- ratio and pH of solution were constant indicates that the regulatory mechanism is not directly competitive. Regardless of the effect of pH on cumulative uptake of NH4+, the specific nitrogen uptake rates from mixed and from individual NH4+ and NO3- sources oscillated between maxima and minima at each pH with average periodicities similar to the expected interval of leaf emergence.

  4. Role of intracellular pH in ligand internalization

    SciTech Connect

    Hwang, J.; Pouyssegur, J.; Willingham, M.C.; Pastan, I.

    1986-07-01

    Internalization of EGF and transferrin measured as the rate of uptake of /sup 125/I-labeled ligands was compared in the cell line CCL39 and a mutant derivative, PS120, lacking the Na/sup +//H/sup +/ antiport system. No significant alteration was detected between the two cell lines. In contrast, pretreatment of the mutant cells PS-120 with 20 mM NH/sub 4/Cl for 30 min to decrease persistently intracellular pH resulted in an increase in /sup 125/I-EGF and /sup 125/I-transferrin uptake by 60% and 25%, respectively. However, similar NH/sub 4/Cl pretreatment of the parental cell line, CCL-39, which only affected intracellular pH very transiently did not cause an increase of ligand uptake. The binding of /sup 125/I-EGF to CCL-39 and PS-120 cells with or without NH/sub 4/Cl pretreatment showed that NH/sub 4/Cl pretreatment did not affect EGF binding in either CCL-39 or PS-120 cells. Since cells regulate intracellular pH by ion transport systems, we also examined the role of Na/sup +/, K/sup +/ -ATPase. Ouabain, an inhibitor of Na/sup +/, K/sup +/ -ATPases, showed no effect on /sup 125/I-EGF uptake in either of the cell types with or without NH/sub 4/Cl pretreatment. Taken together, these results suggest that the plasma membrane-bound Na/sup +//H/sup +/ antiport, a major pH/sub i/-regulating system in vertebrates, indirectly plays a role in ligand internalization through regulation of intracellular pH.

  5. Production of microbial rhamnolipid by Pseudomonas aeruginosa MM1011 for ex situ enhanced oil recovery.

    PubMed

    Amani, Hossein; Müller, Markus Michael; Syldatk, Christoph; Hausmann, Rudolf

    2013-07-01

    Recently, several investigations have been carried out on the in situ bacteria flooding, but the ex situ biosurfactant production and addition to the sand pack as agents for microbial enhanced oil recovery (MEOR) has little been studied. In order to develop suitable technology for ex situ MEOR processes, it is essential to carry out tests about it. Therefore, this work tries to fill the gap. The intention of this study was to investigate whether the rhamnolipid mix could be produced in high enough quantities for enhanced oil recovery in the laboratory scale and prove its potential use as an effective material for field application. In this work, the ability of Pseudomonas aeruginosa MM1011 to grow and produce rhamnolipid on sunflower as sole carbon source under nitrogen limitation was shown. The production of Rha-C10-C10 and Rha2-C10-C10 was confirmed by thin-layer chromatography and high-performance liquid chromatography analysis. The rhamnolipid mixture obtained was able to reduce the surface and interfacial tension of water to 26 and 2 mN/m, respectively. The critical micelle concentration was 120 mg/L. Maximum rhamnolipid production reached to about 0.7 g/L in a shake flask. The yield of rhamnolipid per biomass (Y RL/x ), rhamnolipid per sunflower oil (Y RL/s ), and the biomass per sunflower oil (Y x/s ) for shake flask were obtained about 0.01, 0.0035, and 0.035 g g(-1), respectively. The stability of the rhamnolipid at different salinities, pH and temperature, and also, its emulsifying activity has been investigated. It is an effective surfactant at very low concentrations over a wide range of temperatures, pHs, and salt concentrations, and it also has the ability to emulsify oil, which is essential for enhanced oil recovery. With 120 mg/L rhamnolipid, 27 % of original oil in place was recovered after water flooding from a sand pack. This result not only suggests rhamnolipids as appropriate model biosurfactants for MEOR, but it even shows the potential as a biosurfactant of choice for actual MEOR applications. PMID:23640261

  6. VLA 7mm Observations Toward the Pumping Heart of GGD27

    NASA Astrophysics Data System (ADS)

    Linz, H.; Hofner, P.; Araya, E.; Rodríguez, L. F.; Kurtz, S.; Martí, J.; Stecklum, B.; Henning, Th.

    2004-08-01

    While more and more theoretical investigations point to the formation of massive stars via (non-)spherical accretion, direct observational evidence for accretion disks around young high-mass stars is not easy to obtain. Mostly, we still have to deal with more or less indirect hints for their existence. Here we report progress on our project to unveil the nature of the central source of GGD27, a well-studied region of massive star formation from centimeter to the X-ray wavelengths, also known as HH80-81. Previous studies have revealed a deeply embedded massive YSO (1.7 - 2.0 × 104 Lsun) in GGD27 that drives one of the largest stellar radio jets observed so far. The jet appears to be very well collimated which entails questions about the collimating structures. Furthermore, the source illuminates a splendiferous NIR reflection nebula while it remains invisible at wavelengths < 3 ?m. Both facts are indications for a non-spherical mass distribution around this central source. We used the VLA in its B configuration at a wavelength of 7 mm to scrutinise the central source on linear scales of < 300 AU. The data were obtained by applying a maser cross calibration technique using strong 44 GHz methanol masers in the vicinity of GGD27. Compared to our previous 1.3 cm data with similar resolution, we find a clear change in deconvolved position angle for the central source. This provides strong evidence for the existence of a circumstellar structure clearly inclined wrt the jet axis. We discuss or findings which imply that GGD27 is a premium candidate for a circumstellar disk around a young massive star. We demonstrate the need for still higher spatial resolution. Furthermore, we present first results of our efforts to obtain complementary high-resolution data in the thermal infrared. H.L. and B.S. have been supported by DFG grant Ste 605/17-2. P.H. acknowledges partial support from the Research Corporation grant No CC4996, as well as from NSF grant AST-0098524.

  7. Effects of pH and phosphate on CeO2 nanoparticle dissolution.

    PubMed

    Dahle, Jessica T; Livi, Ken; Arai, Yuji

    2015-01-01

    As the result of rapidly grown nanotechnology industries, release of engineered nanoparticles (ENPs) to environment has increased, posing in a serious risk to environmental and human health. To better understand the chemical fate of ENPs in aquatic environments, solubility of CeO2 NPs was investigated using batch dissolution experiments as a function of pH (1.65-12.5), [phosphate] and particle size (33 and 78 nm). It was found that CeO2 dissolution was only significant at pH<5 and inversely proportional to surface area. After 120 h, the release of Ce was ?3 times greater in large NPs than that in small NPs that is likely contributed by the difference in exchangeable Ce(III) impurity (small: 0.3 mM kg(-1), large: 1.56 mM kg(-1)). When 100 ?M of phosphate was added, the dissolution rate of CeO2 NPs was decreased in small NPs by 15% at pH 1.65 and 75% at pH 4.5 and in large NPs by 56% at pH 1.65 and 63% at pH 4.5. The inner-sphere surface complexation of P that is revealed by the zeta potential measurements is effectively suppressing the CeO2 NP dissolution. Predicting the fate and transport of CeO2 NPs in aquatic environment, pH and P ligands might play important roles in controlling the solubility of CeO2 NPs. PMID:24630459

  8. The action of trialkyltin compounds on mitochondrial respiration. The effect of pH.

    PubMed

    Dawson, A P; Selwyn, M J

    1974-03-01

    1. Inhibition of 2,4-dinitrophenol-stimulated respiration by trialkyltins is dependent on the presence of Cl(-) in the assay medium and is only apparent at acid pH values. It appears to be a result of the Cl(-)-OH(-) exchange mediated by trialkyltins. 2. In a KCl medium at alkaline pH values, the maximum rate of respiration produced by uncouplers is further increased by the presence of trialkyltins. 3. The inhibition of uncoupled succinate oxidation at acid pH values is not reversed by increasing the external substrate concentration, suggesting that depletion of intramitochondrial succinate is not an important factor in the inhibition. 4. It is suggested that the probable explanation for these observations is that in the presence of Cl(-) trialkyltins alter the internal pH to a more acid value and this directly affects the activity of one or more steps in succinate oxidation. 5. The oligomycin-like action of trialkyltins in a Cl(-)-free medium shows considerable pH-dependence over the pH range 6.6-7.6 in the presence of 10mm-phosphate, but very much less pH-dependence in the presence of 1mm-phosphate. 6. The binding of triethyltin to mitochondria shows a pK at pH6.3 and does not change greatly over the pH range 6.6-7.6. 7. It is suggested that the pH-dependence of the oligomycin-like action described by Coleman & Palmer (1971) is the result of the pH-dependence of the formation of a hydrophilic complex between trialkyltins and P(i). PMID:4429539

  9. G11.92-0.61-MM2: A Bonafide Massive Prestellar Core?

    NASA Astrophysics Data System (ADS)

    Cyganowski, C. J.; Brogan, C. L.; Hunter, T. R.; Graninger, D.; Öberg, K. I.; Vasyunin, A.; Zhang, Q.; Friesen, R.; Schnee, S.

    2014-11-01

    Core accretion models of massive star formation require the existence of stable massive starless cores, but robust observational examples of such objects have proven elusive. We report subarcsecond-resolution Submillimeter Array (SMA) 1.3 mm, 1.1 mm, and 0.88 mm and Very Large Array 1.3 cm observations of an excellent massive starless core candidate, G11.92-0.61-MM2, initially identified in the course of studies of GLIMPSE Extended Green Objects (EGOs). Separated by ~7.''2 from the nearby MM1 protostellar hot core, MM2 is a strong, compact dust continuum source (submillimeter spectral index ? = 2.6 ± 0.1), but is devoid of star formation indicators. In contrast to MM1, MM2 has no masers, no centimeter continuum, and no (sub)millimeter wavelength line emission in ~24 GHz of bandwidth observed with the SMA, including N2H+(3-2), HCO+(3-2), and HCN(3-2). Additionally, there is no evidence for an outflow driven by MM2. The (sub)millimeter spectral energy distribution of MM2 is best fit with a dust temperature of ~17-19 K and luminosity of ~5-7 L ?. The combined physical properties of MM2, as inferred from its dust continuum emission, are extreme: M >~ 30 M ? within a radius <1000 AU, N_H_2>1025 cm-2 and n_H_2 >109 cm-3. Comparison of the molecular abundance limits derived from our SMA observations with gas-grain chemical models indicates that extremely dense (n(H) Gt 108 cm-3), cold (<20 K) conditions are required to explain the lack of observed (sub)millimeter line emission, consistent with the dust continuum results. Our data suggest that G11.92-0.61-MM2 is the best candidate for a bonafide massive prestellar core found to date, and a promising target for future higher-sensitivity observations.

  10. Using MM5v3 with Eta Analyses for Air-Quality Modeling at the EPA

    Microsoft Academic Search

    Tanya L. Otte

    MM5 Version 3 (MM5v3, e. g., Dudhia et al. 2000) is attractive for providing meteorological fields to drive air-quality modeling at the EPA for several reasons. Aside from the year-2000 compliance and improved I\\/O formatting, MM5v3 formally supports the use of Eta analyses (Black 1994; Rogers et al. 1995, 1996) as first-guess fields for initialization. In addition, the 30-second surface

  11. A practical large scale/high speed data distribution system using 8 mm libraries

    NASA Technical Reports Server (NTRS)

    Howard, Kevin

    1993-01-01

    Eight mm tape libraries are known primarily for their small size, large storage capacity, and low cost. However, many applications require an additional attribute which, heretofore, has been lacking -- high transfer rate. Transfer rate is particularly important in a large scale data distribution environment -- an environment in which 8 mm tape should play a very important role. Data distribution is a natural application for 8 mm for several reasons: most large laboratories have access to 8 mm tape drives, 8 mm tapes are upwardly compatible, 8 mm media are very inexpensive, 8 mm media are light weight (important for shipping purposes), and 8 mm media densely pack data (5 gigabytes now and 15 gigabytes on the horizon). If the transfer rate issue were resolved, 8 mm could offer a good solution to the data distribution problem. To that end Exabyte has analyzed four ways to increase its transfer rate: native drive transfer rate increases, data compression at the drive level, tape striping, and homogeneous drive utilization. Exabyte is actively pursuing native drive transfer rate increases and drive level data compression. However, for non-transmitted bulk data applications (which include data distribution) the other two methods (tape striping and homogeneous drive utilization) hold promise.

  12. In Vivo Model to Test Implanted Biosensors for Blood pH

    NASA Technical Reports Server (NTRS)

    Arnaud, Sara B.; Somps, Chris J.; Madou, Marc; Hines, John; Wade, Charles E. (Technical Monitor)

    1997-01-01

    Biosensors for monitoring physiologic data continuously through telemetry are available for heart rate, respiration, and temperature but not for blood pH or ions affected by hydrogen ion concentration. A telemetric biosensor for monitoring blood pH on-line could be used to identify and manage problems in fluid and electrolyte metabolism, cardiac and respiratory function during space flight and the acid-base status of patients without the need for venipuncture in patients on Earth. Critical to the development of biosensors is a method for evaluating their performance after implantation. Mature rats, prepared with jugular, cannulas for repeated blood samples, were exposed to a gas mixture containing high levels of carbon dioxide (7%) in a closed environment to induce mild respiratory acidosis. Serial blood gas and pH measurements in venous blood were compared with electrical responses from sensors implanted in the subcutaneous tissue. Animals became slightly tachypneic after exposure to excess CO2, but remained alert and active. After 5 minutes, basal blood pH decreased from 7.404 +/- 0.013 to 7.289 +/- 0.010 (p less than 0.001)and PC02 increased from 45 +/- 6 to 65 +/- 4 mm. Hg (p les than 0.001). Thereafter pH and blood gas parameters remained stable. Implanted sensors showed a decrease in millivolts (mV) which paralleled the change in pH and averaged 5-6 mV per 0.1 unit pH. Implanted sensors remained sensitive to modest changes in tissue pH for one week. A system for inducing acidosis in rats was developed to test the in vivo performance of pH biosensors. The system provides a method which is sensitive, rapid and reproducible in the same and different animals with full recovery, for testing the performance of sensors implanted in subcutaneous tissues.

  13. The pH Factor

    NSDL National Science Digital Library

    The Miami Museum of Science's learning site, The pH Factor, gives teachers a fun and interactive way to teach elementary and middle school students some basics of science. Material is divided into seven learning areas: excite, explore, explain, expand, extend, exchange, and examine. Each contains an interactive screen that can be used directly in the classroom and lesson plans that correspond with each subject. For example, the excite area contains the "tasting tongue" that, when clicked, shows the location on the tongue where you taste bitter or sour things. The site's teaching style is based on the proposition that learners need to build their own understanding of new ideas. The unique material that is offered on this site provides educators with an excellent alternative for teaching these sometimes difficult concepts to grade school students.

  14. A major water quality problem in smolt farms: combined effects of carbon dioxide, reduced pH and aluminium on Atlantic salmon ( Salmo salar L.) smolts: physiology and growth

    Microsoft Academic Search

    Sveinung Fivelstad; Rune Waagbø; Solveig F Zeitz; Anne Camilla Diesen Hosfeld; Anne Berit Olsen; Sigurd Stefansson

    2003-01-01

    Hatchery reared Atlantic salmon (Salmo salar L.) smolts (mean start weight 80 g) in soft freshwater were exposed to three levels of carbon dioxide partial pressure for 38 days (25 days for the high group) in an open flow system: 0.5 mm Hg (1.8 mg\\/l CO2; pH 6.6; control group), 2.7 mm Hg (9.3 mg\\/l CO2; pH 6.0; medium group)

  15. Doxorubicin physical state in solution and inside liposomes loaded via a pH gradient

    Microsoft Academic Search

    Xingong Li; Donald J. Hirsh; Donna Cabral-Lilly; Achim Zirkel; Sol M. Gruner; Andrew S. Janoff; Walter R. Perkins

    1998-01-01

    We have examined doxorubicin’s (DOX) physical state in solution and inside EPC\\/cholesterol liposomes that were loaded via a transmembrane pH gradient. Using cryogenic electron microscopy (cryo-EM) we noted that DOX loaded to 200–300 mM internal concentrations in citrate containing liposomes formed linear, curved, and circular bundles of fibers with no significant interaction\\/perturbation of the vesicle membrane. The individual DOX fibers

  16. Development of luminescent pH sensor films for monitoring bacterial growth through tissue

    PubMed Central

    Wang, Fenglin; Raval, Yash; Chen, Hongyu; Tzeng, Tzuen-Rong J.; DesJardins, John D.

    2014-01-01

    Although implanted medical devices (IMDs) offer many benefits, they are susceptible to bacterial colonization and infections. Such infections are difficult to treat because bacteria could form biofilms on the implant surface, which reduce antibiotics penetration and generate local dormant regions with low pH and low oxygen. In addition, these infections are hard to detect early because biofilms are often localized on the surface. Herein, an optical sensor film is developed to detect local acidosis on an implanted surface. The film contains both upconverting particles (UCPs) that serve as a light source and a pH indicator that alters the luminescence spectrum. When irradiated with 980 nm light, the UCPs produce deeply penetrating red light emission, while generating negligible autofluorescence in the tissue. The basic form of the pH indicator absorbs more of upconversion luminescence at 661 nm than at 671 nm and consequently the spectral ratio indicates pH. Implanting this pH sensor film beneath 6-7 mm of porcine tissue does not substantially affect the calibration curve because the peaks are closely spaced. Furthermore, growth of Staphylococcus epidermidis on the sensor surface causes a local pH decrease that can be detected non-invasively through the tissue. PMID:23832869

  17. Evaluation of pH at the Bacteria–Dental Cement Interface

    PubMed Central

    Mayanagi, G.; Igarashi, K.; Washio, J.; Nakajo, K.; Domon-Tawaraya, H.; Takahashi, N.

    2011-01-01

    Physiochemical assessment of the parasite-biomaterial interface is essential in the development of new biomaterials. The purpose of this study was to develop a method to evaluate pH at the bacteria-dental cement interface and to demonstrate physiochemical interaction at the interface. The experimental apparatus with a well (4.0 mm in diameter and 2.0 mm deep) was made of polymethyl methacrylate with dental cement or polymethyl methacrylate (control) at the bottom. Three representative dental cements (glass-ionomer, zinc phosphate, and zinc oxide-eugenol cements) were used. Each specimen was immersed in 2 mM potassium phosphate buffer for 10 min, 24 hrs, 1 wk, or 4 wks. The well was packed with Streptococcus mutans NCTC 10449, and a miniature pH electrode was placed at the interface between bacterial cells and dental cement. The pH was monitored after the addition of 1% glucose, and the fluoride contained in the cells was quantified. Glass-ionomer cement inhibited the bacteria-induced pH fall significantly compared with polymethyl methacrylate (control) at the interface (10 min, 5.16 ± 0.19 vs. 4.50 ± 0.07; 24 hrs, 5.20 ± 0.07 vs. 4.59 ± 0.11; 1 wk, 5.34 ± 0.14 vs. 4.57 ± 0.11; and 4 wks, 4.95 ± 0.27 vs. 4.40 ± 0.14), probably due to the fluoride released from the cement. This method could be useful for the assessment of pH at the parasite-biomaterial interface. PMID:21933936

  18. Evaluation of pH at the bacteria-dental cement interface.

    PubMed

    Mayanagi, G; Igarashi, K; Washio, J; Nakajo, K; Domon-Tawaraya, H; Takahashi, N

    2011-12-01

    Physiochemical assessment of the parasite-biomaterial interface is essential in the development of new biomaterials. The purpose of this study was to develop a method to evaluate pH at the bacteria-dental cement interface and to demonstrate physiochemical interaction at the interface. The experimental apparatus with a well (4.0 mm in diameter and 2.0 mm deep) was made of polymethyl methacrylate with dental cement or polymethyl methacrylate (control) at the bottom. Three representative dental cements (glass-ionomer, zinc phosphate, and zinc oxide-eugenol cements) were used. Each specimen was immersed in 2 mM potassium phosphate buffer for 10 min, 24 hrs, 1 wk, or 4 wks. The well was packed with Streptococcus mutans NCTC 10449, and a miniature pH electrode was placed at the interface between bacterial cells and dental cement. The pH was monitored after the addition of 1% glucose, and the fluoride contained in the cells was quantified. Glass-ionomer cement inhibited the bacteria-induced pH fall significantly compared with polymethyl methacrylate (control) at the interface (10 min, 5.16 ± 0.19 vs. 4.50 ± 0.07; 24 hrs, 5.20 ± 0.07 vs. 4.59 ± 0.11; 1 wk, 5.34 ± 0.14 vs. 4.57 ± 0.11; and 4 wks, 4.95 ± 0.27 vs. 4.40 ± 0.14), probably due to the fluoride released from the cement. This method could be useful for the assessment of pH at the parasite-biomaterial interface. PMID:21933936

  19. Pyrite oxidation at circumneutral pH

    Microsoft Academic Search

    C. O Moses; J. S Herman

    1991-01-01

    Previous studies of pyrite oxidation kinetics have concentrated primarily on the reaction at low pH, where Fe(III) has been assumed to be the dominant oxidant. Studies at circumneutral pH, necessitated by effective pH buffering in some pyrite oxidation systems, have often implicitly assumed that the dominant oxidant must be dissolved oxygen (DO), owing to the diminished solubility of Fe(III). In

  20. Middle School and pH?

    NSDL National Science Digital Library

    Susan Herricks

    2007-02-01

    A local middle school requested that the Water Center of Advanced Materials for Purification of Water With Systems (WaterCAMPWS), a National Science Foundation Science and Technology Center, provide an introduction to pH for their seventh-grade water-based service learning class. As a result, the grade-appropriate, hands-on laboratory, "Creating the pH Scale" was developed to help students grasp the fundamentals of pH.

  1. Anthropogenic carbon and ocean pH

    Microsoft Academic Search

    K. Caldeira; Michael E. Wickett

    2003-01-01

    ocean 1 with potentially adverse consequences for marine biota 2-4 . We quantify pH changes that may result from continued release of fossil-fuel CO 2 to the atmosphere, and compare these with pH changes inferred from geological and historical records. We conclude that releasing fossil-fuel CO 2 to the atmosphere over several centuries may result in ocean pH changes greater

  2. Hans Peter Schwefel Wireless Networks III, Fall 2005: MM3, Wireless Services

    E-print Network

    Schwefel, Hans-Peter

    Networks III: advanced concepts Hans-Peter Schwefel and Tatiana K. Madsen hps@kom.auc.dk tatiana@kom.auc.dk http://www.kom.auc.dk/~hps http://www.kom.auc.dk/~tatiana · Mm1 IP Mobility Support (HPS) · Mm2

  3. Hans Peter Schwefel Wireless Networks III, Fall 2005: MM1, IP Mobility Support

    E-print Network

    Schwefel, Hans-Peter

    Networks III: advanced concepts Hans-Peter Schwefel and Tatiana K. Madsen hps@kom.auc.dk tatiana@kom.auc.dk http://www.kom.auc.dk/~hps http://www.kom.auc.dk/~tatiana · Mm1 IP Mobility Support (HPS) · Mm2

  4. Effect of thermal shield and gas flow on thermal elastic stresses in 300 mm silicon crystal

    Microsoft Academic Search

    Yu GAO; Qinghua XIAO; Qigang ZHOU; Xiaolin DAI; Hailing TU

    2006-01-01

    The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm Si crystal under the consideration of different thermal shields and gas flow

  5. Experimental Media, Component List Component MW g/mol Ames mg/L Ames mM L-15 mg/L L-15 mM BME mg/L BME mM Locke's mg/L Locke's mM

    E-print Network

    Rieke, Fred

    -Valine Vitamins Ascorbic acid · Na D-Biotin Choline chloride Folic acid myo-Inositol Niacinamide D/L BME mM Locke's mg/L Locke's mM Salts CaCl2 · 2H2O CaCl2 Magnesium Chloride MgSO4 (anhyd) KCl KH2PO4 Na

  6. Assessment of QM/MM scoring functions for molecular docking to HIV-1 protease.

    PubMed

    Fong, Pedro; McNamara, Jonathan P; Hillier, Ian H; Bryce, Richard A

    2009-04-01

    We explore the ability of four quantum mechanical (QM)/molecular mechanical (MM) models to accurately identify the native pose of six HIV-1 protease inhibitors and compare them with the AMBER force field and ChemScore and GoldScore scoring functions. Three QM/MM scoring functions treated the ligand at the HF/6-31G*, AM1d, and PM3 levels; the fourth QM/MM function modeled the ligand and active site at the PM3-D level. For the discrimination of native from non-native poses, solvent-corrected HF/6-31G*:AMBER and AMBER functions exhibited the best overall performance. While the electrostatic component of the MM and QM/MM functions appears important for discriminating the native pose of the ligand, the polarization contribution in the QM/MM functions was relatively insensitive to a ligand's binding mode and, for one ligand, actually hindered discrimination. The inclusion of a desolvation penalty, here using a generalized Born solvent model, improved discrimination for the MM and QM/MM methods. There appeared to be no advantage to binding mode prediction by incorporating active site polarization at the PM3-D level. Finally, we found that choice of the protonation state of the aspartyl dyad in the HIV-1 protease active site influenced the ability of scoring methods to determine the native binding pose. PMID:19309119

  7. QM/MM studies of Phosphothreonine Lyase Catalysis in Bacterial Effector SpvC

    E-print Network

    Maccabe, Barney

    QM/MM studies of Phosphothreonine Lyase Catalysis in Bacterial Effector SpvC Zhihong Ke1 and density functional theory study of phosphothreonine lyase catalysis. J. Phys. Chem. B;113/mol, in excellent agreement with the experimental result. In contrast to the DFT study, the ab initio QM/MM MD

  8. The Asymptotics of MM-Estimators for Linear Regression with Fixed Designs

    Microsoft Academic Search

    Matias Salibian-Barrera

    2006-01-01

    MM-estimators achieve simultaneous high efficiency and high breakdown point over contamination neighborhoods. Inference based on these estimators relies on their asymptotic properties, which have been studied for the case of random covariates. In this paper we show that, under relatively mild regularity conditions, MM-estimators for linear regression models are strongly consistent when the design is fixed. Moreover, their strong consistency

  9. Hybrid QM/MM Car-Parrinello Simulations of Catalytic and Enzymatic Reactions

    E-print Network

    Guidoni, Leonardo

    1 Hybrid QM/MM Car-Parrinello Simulations of Catalytic and Enzymatic Reactions MariaCarola Colombo for the in situ investigation of chemical reactions that occur in a complex and heterogeneous environment. Here technique. Keywords: Car-Parrinello first-principles molecular dynamics, QM/MM simulations, enantioselective

  10. Terminal ballistics of the 7.62 mm NATO bullet autopsy findings

    Microsoft Academic Search

    Peter J. T. Knudsen; Peter Theilade

    1993-01-01

    Summary The 7.62 mm × 51 military rifle bullet (7.62 mm NATO) as manufactured in Denmark, and in some other countries as well, has been claimed to fragment when fired at ranges encountered in forensic practice. All autopsied cases of death due to this bullet in Denmark since 1975 were investigated by studying autopsy reports and the bullets retrieved by

  11. ALUMINUM SITING IN THE ZSM-22 AND THETA-1 ZEOLITES REVISITED: A QM/MM STUDY

    E-print Network

    Sklenak, Stepan

    ALUMINUM SITING IN THE ZSM-22 AND THETA-1 ZEOLITES REVISITED: A QM/MM STUDY Stepan SKLENAKa1 on the occasion of his 80th birthday. The Al siting in the silicon rich ZSM-22 and Theta-1 zeolites of the TON. Keywords: QM/MM calculations; Ab initio calculations; BLYP; GIAO; Zeolites; 27 Al 3Q MAS NMR spectroscopy

  12. pH Meter probe assembly

    DOEpatents

    Hale, Charles J. (San Jose, CA)

    1983-01-01

    An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe.

  13. pH Meter probe assembly

    DOEpatents

    Hale, C.J.

    1983-11-15

    An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe. 1 fig.

  14. UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM

    E-print Network

    Carpick, Robert W.

    UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM GUIDELINES FOR GRADUATE STUDY September 2013 Mechanical Engineering and Applied Mechanics School of Engineering and Applied Science University of Pennsylvania 229

  15. UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM

    E-print Network

    Carpick, Robert W.

    UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM GUIDELINES FOR GRADUATE STUDY September 2009 Mechanical Engineering and Applied Mechanics School of Engineering and Applied Science University of Pennsylvania 229

  16. UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM

    E-print Network

    Carpick, Robert W.

    UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM GUIDELINES FOR GRADUATE STUDY September 2010 Mechanical Engineering and Applied Mechanics School of Engineering and Applied Science University of Pennsylvania 229

  17. UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM

    E-print Network

    Carpick, Robert W.

    UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM GUIDELINES FOR GRADUATE STUDY September 2011 Mechanical Engineering and Applied Mechanics School of Engineering and Applied Science University of Pennsylvania 229

  18. UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM

    E-print Network

    Carpick, Robert W.

    UNIVERSITY of PENNSYLVANIA Ph.D. PROGRAM GUIDELINES FOR GRADUATE STUDY September 2012 Mechanical Engineering and Applied Mechanics School of Engineering and Applied Science University of Pennsylvania 229

  19. pH regulation in anoxic rice coleoptiles at pH 3.5: biochemical pHstats and net H+ influx in the absence and presence of NOFormula.

    PubMed

    Greenway, Hank; Kulichikhin, Konstantin Y; Cawthray, Gregory R; Colmer, Timothy D

    2012-03-01

    During anoxia, cytoplasmic pH regulation is crucial. Mechanisms of pH regulation were studied in the coleoptile of rice exposed to anoxia and pH 3.5, resulting in H(+) influx. Germinating rice seedlings survived a combination of anoxia and exposure to pH 3.5 for at least 4 d, although development was retarded and net K(+) efflux was continuous. Further experiments used excised coleoptile tips (7-10 mm) in anoxia at pH 6.5 or 3.5, either without or with 0.2 mM NO(3)(-), which distinguished two processes involved in pH regulation. Net H(+) influx (?mol g(-1) fresh weight h(-1)) for coleoptiles with NO(3)(-) was ?1.55 over the first 24 h, being about twice that in the absence of NO(3)(-), but then decreased to 0.5-0.9 as net NO(3)(-) uptake declined from ?1.3 to 0.5, indicating reduced uptake via H(+)-NO(3)(-) symports. NO(3)(-) reduction presumably functioned as a biochemical pHstat. A second biochemical pHstat consisted of malate and succinate, and their concentrations decreased substantially with time after exposure to pH 3.5. In anoxic coleoptiles, K(+) balancing the organic anions was effluxed to the medium as organic anions declined, and this efflux rate was independent of NO(3)(-) supply. Thus, biochemical pHstats and reduced net H(+) influx across the plasma membrane are important features contributing to pH regulation in anoxia-tolerant rice coleoptiles at pH 3.5. PMID:22174442

  20. Design of the multilayer insulation system for the Superconducting Super Collider 50mm dipole cryostat

    SciTech Connect

    Boroski, W.N.; Nicol, T.H.; Schoo, C.J.

    1991-03-01

    The development of the multilayer insulation (MLI) system for the Superconducting Super Collider (SSC) 50 mm collider dipole cryostat is an ongoing extension of work conducted during the 40 mm cryostat program. While the basic design of the MLI system for the 50 mm cryostat resembles that of the 40 mm cryostat, results from measurements of MLI thermal performance below 80K have prompted a re-design of the MLI system for the 20K thermal radiation shield. Presented is the design of the MLI system for the 50 mm collider dipole cryostat, with discussion focusing on system performance, blanket geometry, cost-effective fabrication techniques, and built-in quality control measures that assure consistent thermal performance throughout the SSC accelerator. 16 refs., 8 figs., 2 tabs.

  1. Effect of External pH on the Internal pH of Chlorella saccharophila1

    PubMed Central

    Gehl, Katharina A.; Colman, Brian

    1985-01-01

    The overall internal pH of the acid-tolerant green alga, Chlorella saccharophila, was determined in the light and in the dark by the distribution of 5,5-dimethyl-2-[14C]oxazolidine-2,4-dione ([14C]DMO) or [14C]benzoic acid ([14C]BA) between the cells and the surrounding medium. [14C]DMO was used at external pH of 5.0 to 7.5 while [14C]BA was used in the range pH 3.0 to pH 5.5. Neither compound was metabolized by the algal cells and intracellular binding was minimal. The internal pH of the algae obtained with the two compounds at external pH values of 5.0 and 5.5 were in good agreement. The internal pH of C. saccharophila remained relatively constant at pH 7.3 over the external pH range of pH 5.0 to 7.5. Below pH 5.0, however, there was a gradual decrease in the internal pH to 6.4 at an external pH of 3.0. The maintenance of a constant internal pH requires energy and the downward drift of internal pH with a drop in external pH may be a mechanism to conserve energy and allow growth at acid pH. PMID:16664162

  2. Is cholecystectomy a reasonable treatment option for simple gallbladder polyps larger than 10 mm?

    PubMed Central

    Park, Hye Yon; Oh, Se Hoon; Lee, Kwang Hyuck; Lee, Jong Kyun; Lee, Kyu Taek

    2015-01-01

    AIM: To determine the relevance of the 10-mm size criterion of the generally accepted surgical indication for gallbladder polyps (GBPs). METHODS: We collected data of patients who were confirmed to have GBPs through cholecystectomy at Samsung Medical Center between January 1997 and December 2012. Among the patients who underwent cholecystectomy for GBP, those with a definite evidence for malignancy such as adjacent organ invasion, metastasis on preoperative imaging studies, polyp larger than 20 mm, absence of preoperative imaging study results, and patients having gallstones were excluded. We retrospectively collected and analyzed information on patient’s clinical characteristics, symptoms, ultrasonographic findings, and blood laboratory tests. RESULTS: A total of 836 patients who had undergone cholecystectomy were retrospectively analyzed. Seven hundred eighty patients (93%) had benign polyps, whereas 56 patients (7%) had malignant polyps. Of the 56 patients with malignancy, 4 patients (7%) had borderline GBP (10-12 mm) and a patient had small GBP (< 10 mm) with T2 stage. We conducted an ROC curve analysis to verify the 10-mm size criteria (AUC = 0.887, SD = 0.21, P < 0.001). In the ROC curve for polyp size and malignancy, sensitivity and specificity of the 10-mm size criterion was 98.2% and 19.6%, respectively. The specificity of the 11-mm and 12-mm size criteria was 44.6% and 56%, respectively, whereas the sensitivity of these two size criteria was similar. We defined the GBPs of 10 to 12 mm as a borderline-sized GBP, which were found in 411 patients (49%). In this group, there was a significant difference in age between patients with benign and malignant GBPs (47 years vs 60 years, P < 0.05). CONCLUSION: GBPs larger than 13 mm need immediate excision whereas for borderline-sized GBPs detected in young patients, careful medical observation can be a rational decision.

  3. Originating Agency Agency Code Interest Eligible (Y/N) Payment Date (MM) (DD) (YY) OSC Use Only Liability Date (MM) (DD) (YY)

    E-print Network

    Suzuki, Masatsugu

    Originating Agency Agency Code Interest Eligible (Y/N) N Payment Date (MM) (DD) (YY) OSC Use Only By __________________________________________________ Agency Finance Office Use I certify that this claim is correct and just, and that this payment ____________________________________________________________ Title Date Expenditure Liquidation Cost Center Code Accum Object Amount Orig. Agency PO/Contract Line F

  4. Effect of HCO-3 and pH on ion transport in the posterior intestine of the freshwater-adapted teleost Anguilla anguilla.

    PubMed

    Baldisserotto, B; Mimura, O M

    1995-03-01

    The intestinal mucosa may be exposed to acidic or alcaline solutions due to liberation of digestive secretions. In several situations blood pH may also change. Consequently, the effects of HCO-3, CO2, and pH variation of medium on the ion transport across the posterior intestine of the eel (Anguilla anguilla) adapted to freshwater were studied in terms of fractional values of short-circuit current (SCC), transepithelial potential difference (TPD) and conductance (G). Immature eels weighing 100-200 g were used. The control physiological solution contained: 118.5 mM NaCl, 25.0 mM NaHCO3, 3.0 mM CaCl2.2H2O, 4.7 mM KCl, 1.0 mM MgCl2.6H2O, 5.0 mM D-glucose, 10.0 mM D-mannitol, pH 7.80, ans was gassed with 98% O2-2% CO2. Control values (N = 21) were: SCC = 51.90 +/- 2.8 microA.cm-2, TPD = 2.33 +/- 0.1 mV, G = 22.43 +/- 0.6 mS.cm-2. At constant pH, the reduction of HCO-3 concentration to 50% and 10% did not alter the values of SCC and TPD, but G increased with HCO-3 reduction to 10%. In the absence of HCO-3, SCC, TPD and G (slightly) decreased, but 1.5 mM HCO-3 still maintained the ion transport within control values, at constant pH. Comparing pH values from 6.65 to 8.61, higher values of SCC and TPD were observed at pH 7.45, but were little affected below and above this pH. There was a significant correlation between pH and SCC and TPD values; from the regression equations (1) SCC was zero at pHs below 6.62 and above 8.78 and (2) TPD was zero below 6.50 and above 8.71. PMID:8520526

  5. Use of a Genetically Enhanced, Pediocin-Producing Starter Culture, Lactococcus lactis subsp. lactis MM217, To Control Listeria monocytogenes in Cheddar Cheese

    PubMed Central

    Buyong, Nurliza; Kok, Jan; Luchansky, John B.

    1998-01-01

    Cheddar cheese was prepared with Lactococcus lactis subsp. lactis MM217, a starter culture which contains pMC117 coding for pediocin PA-1. About 75 liters of pasteurized milk (containing ca. 3.6% fat) was inoculated with strain MM217 (ca. 106 CFU per ml) and a mixture of three Listeria monocytogenes strains (ca. 103 CFU per ml). The viability of the pathogen and the activity of pediocin in the cheese were monitored at appropriate intervals throughout the manufacturing process and during ripening at 8°C for 6 months. In control cheese made with the isogenic, non-pediocin-producing starter culture L. lactis subsp. lactis MM210, the counts of the pathogen increased to about 107 CFU per g after 2 weeks of ripening and then gradually decreased to about 103 CFU per g after 6 months. In the experimental cheese made with strain MM217, the counts of L. monocytogenes decreased to 102 CFU per g within 1 week of ripening and then decreased to about 10 CFU per g within 3 months. The average titer of pediocin in the experimental cheese decreased from approximately 64,000 arbitrary units (AU) per g after 1 day to 2,000 AU per g after 6 months. No pediocin activity (<200 AU per g) was detected in the control cheese. Also, the presence of pMC117 in strain MM217 did not alter the cheese-making quality of the starter culture, as the rates of acid production, the pH values, and the levels of moisture, NaCl, and fat of the control cheese and the experimental cheese were similar. Our data revealed that pediocin-producing starter cultures have significant potential for protecting natural cheese against L. monocytogenes. PMID:9835572

  6. Corneal Optical Quality Following Sub 1.8 mm Micro-Incision Cataract Surgery vs. 2.2 mm Mini-Incision Coaxial Phacoemulsification

    PubMed Central

    Alió, Jorge L.; Elkady, Bassam; Ortiz, Dolores

    2010-01-01

    Purpose: To study and compare the effects of the micro-incision cataract surgery (MICS-sub 1.8 mm) and miniincision coaxial phacoemulsification (2.2 mm) on the optical quality of the cornea characterized in terms of corneal aberrations. Materials and Methods: Fifty eyes underwent MICS and 50 mini-incision phacoemulsification, by the same surgeon. Both types of cataract surgery were performed using low ultrasound power and through a clear corneal incision, placed on the steepest corneal meridian ranging from 1.6 to 1.8 in MICS (Group I) and from 2.12 to 2.3 mm in mini-incision coaxial phacoemulsification (Group II). Seidel and Zernike aberration coefficients and RMS values were obtained for a 6-mm pupil preoperatively and one month after surgery. Results: The corneal astigmatism did not show statistically significant changes in either of the two groups: (MICS: –0.73 ± 0.63, –0.65 ± 0.53 D, P = 0.25), (mini-incision phacoemulsification; –1.21 ± 1.52, –1.00 ± 1.19 D, P = 0.12). The total RMS remained unchanged after MICS (1.77 ± 1.7, 1.65 ± 1.3 ?m, P = 0.18) and mini-incision phacoemulsification (2.00 ± 1.87, 2.09 ± 1.8 ?m, P = 0.41). Statistically significant changes were found for coma (P = 0.004) and higher-order aberrations (P < 0.001), showing MICS significantly less changes in cornea. Conclusions: Both MICS and mini-incision phacoemulsification do not degrade the optical quality of the cornea. Both surgeries do not induce a modification of the corneal astigmatism, even in the axis. It seems that 2 mm is the limit around which no optical changes are induced by cataract surgery in the human cornea. PMID:20543945

  7. PhET Simulation: Estimation

    NSDL National Science Digital Library

    Physics Education Technology Project

    This interactive Flash animation allows students to explore size estimation in one, two and three dimensions. Multiple levels of difficulty allow for progressive skill improvement. In the simplest level, users estimate the number of small line segments that can fit into a larger line segment. Intermediate and advanced levels offer feature games that explore area of rectangles and circles, and volume of spheres and cubes. Related lesson plans and student guides are available for middle school and high school classroom instruction. Editor's Note: When the linear dimensions of an object change by some factor, its area and volume change disproportionately: area in proportion to the square of the factor and volume in proportion to its cube. This concept is the subject of entrenched misconception among many adults. This game-like simulation allows kids to use spatial reasoning, rather than formulas, to construct geometric sense of area and volume. This is part of a larger collection developed by the Physics Education Technology project (PhET).

  8. Pioneering breakthroughs in implant monitor wafer cost reduction at 300 mm

    NASA Astrophysics Data System (ADS)

    Zeakes, Jason S.; Breeden, Terry A.

    1999-08-01

    The semiconductor industry has been full of news regarding the transition to 300 mm wafers. In 1998, SEMICONDUCTOR300 (SC300) was the first to demonstrate the capability to produce integrated products on 300 mm wafers. To meet the challenge of maintaining quality while simultaneously reducing cost and ramping SC300 into pilot manufacturing, the authors have investigated the use of an overlay implant technique. A single 300 mm wafer is used to collect particle, high dose, and low dose information from a Eaton GSD HE-3 ion implanter. The implants, a high dose As+ 80 KeV 3E14 followed by a low dose As+ 60 KeV 3E11 damage implant, are measured using a KLA/Tencor Rs100 sheet resistance measurement tool with a 3 mm edge exclusion. In addition to verifying the technique at 300 mm, the paper presents overlay implant data collected using externally reclaimed wafers, currently one third the cost of prime 300 mm wafers, and explores the possibility of reusing implanted monitor wafers by re-annealing the wafers and repeating the low dose damage implant. Initial data is also presented for implants performed on the backside of 300 mm wafers.

  9. Salivary pH: A diagnostic biomarker

    PubMed Central

    Baliga, Sharmila; Muglikar, Sangeeta; Kale, Rahul

    2013-01-01

    Objectives: Saliva contains a variety of host defense factors. It influences calculus formation and periodontal disease. Different studies have been done to find exact correlation of salivary biomarkers with periodontal disease. With a multitude of biomarkers and complexities in their determination, the salivary pH may be tried to be used as a quick chairside test. The aim of this study was to analyze the pH of saliva and determine its relevance to the severity of periodontal disease. Study Design: The study population consisted of 300 patients. They were divided into three groups of 100 patients each: Group A had clinically healthy gingiva, Group B who had generalized chronic gingivitis and Group C who had generalized chronic periodontitis. The randomized unstimulated saliva from each patient was collected and pH was tested. Data was analyzed statistically using analysis of variance technique. Results: The salivary pH was more alkaline for patients with generalized chronic gingivitis as compared with the control group (P = 0.001) whereas patients with generalized chronic periodontitis had more acidic pH as compared with the control group (P = 0.001). Conclusion: These results indicate a significant change in the pH depending on the severity of the periodontal condition. The salivary pH shows significant changes and thus relevance to the severity of periodontal disease. Salivary pH may thus be used as a quick chairside diagnostic biomarker. PMID:24174725

  10. pH. Agricultural Lesson Plans.

    ERIC Educational Resources Information Center

    Southern Illinois Univ., Carbondale. Dept. of Agricultural Education and Mechanization.

    This lesson plan is intended for use in conducting classes on the effect of pH on plant growth. Presented first are an attention step/problem statement and a series of questions and answers designed to convey general information about soil pH and its effect on plants. The following topics are among those discussed: acidity and alkalinity; the…

  11. Nursing PhD 2010 Edition

    E-print Network

    Saskatchewan, University of

    Nursing PhD Handbook 2010 Edition 107 Wiggins Rd, Saskatoon SK S7N 5E5 Phone: (306) 966-8239 Fax: (306) 966-6703 Email: grad.nursing@usask.ca #12;Welcome to the College of Nursing Graduate Program & Continuing Nursing Education #12;PhD Manual 2 Table of Contents General Information

  12. CALCULATING THE PH OF CALCIUM CARBONATE SATURATION

    EPA Science Inventory

    Two new expressions for the pH of saturation (pH subs) were derived. One is a simplified equation developed from an aqueous carbonate equilibrium system in which correction for ionic strength was considered. The other is a more accurate quadratic formula that involves computerize...

  13. Middle School and pH?

    ERIC Educational Resources Information Center

    Herricks, Susan

    2007-01-01

    A local middle school requested that the Water Center of Advanced Materials for Purification of Water With Systems (WaterCAMPWS), a National Science Foundation Science and Technology Center, provide an introduction to pH for their seventh-grade water-based service learning class. After sorting through a multitude of information about pH, a…

  14. The Herschel Multi-Tiered Extragalactic Survey: SPIRE-mm Photometric Redshifts

    NASA Technical Reports Server (NTRS)

    Roseboom, I. G.; Ivison, R. J.; Greve, T. R.; Amblard, A.; Arumugam, V.; Auld, R.; Aussel, H.; Bethermin, M.; Blain, A.; Block, J.; Boselli, A.; Brisbin, D.; Buat, V.; Burgarella, D.; Castro-Rodriquez, N.; Cava, A.; Chanial, P.; Chapin, E.; Chapman, S.; Clements, D. L.; Conley, A.; Conversi, L.; Dowell, C. D.; Dunlop, J. S.; Dwek, E.

    2012-01-01

    We investigate the potential of submm-mm and submm-mm-radio photometric redshifts using a sample of mm-selected sources as seen at 250, 350 and 500 micron by the SPIRE instrument on Herschel. From a sample of 63 previously identified mm sources with reliable radio identifications in the Great Observatories Origins Deep Survey North and Lockman Hole North fields, 46 (73 per cent) are found to have detections in at least one SPIRE band. We explore the observed submm/mm color evolution with redshift, finding that the colors of mm sources are adequately described by a modified blackbody with constant optical depth Tau = (Nu/nu(sub 0))(exp Beta), where Beta = +1.8 and nu(sub 0) = c/100 micron. We find a tight correlation between dust temperature and IR luminosity. Using a single model of the dust temperature and IR luminosity relation, we derive photometric redshift estimates for the 46 SPIRE-detected mm sources. Testing against the 22 sources with known spectroscopic or good quality optical/near-IR photometric redshifts, we find submm/mm photometric redshifts offer a redshift accuracy of (absolute value of Delta sub (z))/(1 + z) = 0.16 (absolute value of Delta sub (z)) = 0.51). Including constraints from the radio-far-IR correlation, the accuracy is improved to (absolute value of Delta sub (z))/(1 + z) = 0.14 (((absolute value of Delta sub (z))) = 0.45). We estimate the redshift distribution of mm-selected sources finding a significant excess at Z > 3 when compared to approx 8S0 micron selected samples.

  15. The Herschel Multi-Tiered Extragalactic Survey: SPIRE-mm Photometric Redshifts

    NASA Technical Reports Server (NTRS)

    Roseboom, I. G.; Ivison, R. J.; Greve, T. R.; Amblard, A.; Arumugam, V.; Auld, R.; Aussel, H.; Bethermin, M.; Blain, A.; Bock, J.; Boselli, A.; Brisbin, D.; Buat, V.; Burgarella, D.; Castro-Rodriguez, N.; Cava, A.; Chanial, P.; Chapin, E.; Chapman, S.; Clements, D. L.; Conley, A.; Conversi, L.; Cooray, A.; Dowell, C. D.; Dwek, E.

    2011-01-01

    We investigate the potential of submm-mm and submm-mm-radio photometric red-shifts using a sample of mm-selected sources as seen at 250, 350 and 500 micrometers by the SPIRE instrument on Herschel. From a sample of 63 previously identified mm-sources with reliable radio identifications in the GOODS-N and Lockman Hole North fields 46 (73 per cent) are found to have detections in at least one SPIRE band. We explore the observed submm/mm colour evolution with redshift, finding that the colours of mm-sources are adequately described by a modified blackbody with constant optical depth Tau = (nu/nu(0))beta where beta = +1.8 and nu(0) = c/100 micrometers. We find a tight correlation between dust temperature and IR luminosity. Using a single model of the dust temperature and IR luminosity relation we derive photometric redshift estimates for the 46 SPIRE detected mm-sources. Testing against the 22 sources with known spectroscopic, or good quality optical/near-IR photometric, redshifts we find submm/mm photometric redshifts offer a redshift accuracy of |delta z|/(1+z) = 0.16 (less than |delta z| greater than = 0.51). Including constraints from the radio-far IR correlation the accuracy is improved to |delta z|/(1 + z) = 0.15 (less than |delta z| greater than = 0.45). We estimate the redshift distribution of mm-selected sources finding a significant excess at z greater than 3 when compared to 850 micrometer selected samples.

  16. An, Yuehuei, Adjunct Associate Professor, Bioengineering. MD, Harbin Medical University (China), 1983; MM, Beijing

    E-print Network

    Bolding, M. Chad

    Anderson, David P., Adjunct Professor, Chemical and Biomolecular Engineering. BA, Clemson University, 1973, Northern Arizona University, 1988; PhD, University of California­Irvine, 1994 Ashton, Susanna M., Associate

  17. Comparison of DFT and ab initio QM/MM methods for modelling reaction in chorismate synthase

    NASA Astrophysics Data System (ADS)

    Lawan, Narin; Ranaghan, Kara E.; Manby, Frederick R.; Mulholland, Adrian J.

    2014-07-01

    Quantum mechanics/molecular mechanics (QM/MM) methods are a popular tool in the investigation of enzyme reactions. Here, we compare B3LYP density functional theory (DFT) and ab initio QM/MM methods for modelling the conversion of 5-enolpyruvylshikimate-3-phosphate to chorismate in chorismate synthase. Good agreement with experimental data is only obtained at the SCS-MP2/CHARMM27 level for a reaction mechanism in which phosphate elimination precedes proton transfer. B3LYP predicts reaction energetics that are qualitatively wrong, stressing the need for ab initio QM/MM methods, and caution in interpretation of DFT results for this enzyme.

  18. Hybrid UTD-MM analysis of the scattering by a perfectly conducting semicircular cylinder

    NASA Astrophysics Data System (ADS)

    Srikanth, Sivasankaran; Pathak, Prabhakar H.; Chuang, C. W.

    1986-10-01

    A hybrid UTD-MM technique which combines the uniform geometrical theory of diffraction (UTD) and the method of moments (MM) is employed to analyze efficiently the problem of electromagnetic diffraction of transverse electric (TE) and transverse magnetic (TM) waves by a perfectly conducting semicircular cylinder. An analysis of this problem is useful for understanding the coupling between the mechanisms of edge and convex surface diffraction. The accuracy of the numerical results for the far-zone fields based on this solution is established by comparison with an independent formally exact MM solution.

  19. Measuring units for elastic stockings: priority to mmHg rather than classes.

    PubMed

    Cornu-Thénard, A

    1992-01-01

    Seven incontrovertible arguments show that the only valid measurement unit for elastic stockings is the millimetre of mercury and not a grading system. The mmHg is an international measurement unit; a new European grading system will make prescribing much more difficult; the degree of arterial insufficiency is calculated by taking systolic pressures by Doppler and is expressed in mmHg; in case of superimposition of elastic stocking, pressure add together but not grades; the unit used for pressure instruments is the mmHg; a clinical situation may require a compression force straddled between two grades; finally, new materials will certainly provide increasingly precise forces. PMID:1302322

  20. Determination Of Ph Including Hemoglobin Correction

    DOEpatents

    Maynard, John D. (Albuquerque, NM); Hendee, Shonn P. (Albuquerque, NM); Rohrscheib, Mark R. (Albuquerque, NM); Nunez, David (Albuquerque, NM); Alam, M. Kathleen (Cedar Crest, NM); Franke, James E. (Franklin, TN); Kemeny, Gabor J. (Madison, WI)

    2005-09-13

    Methods and apparatuses of determining the pH of a sample. A method can comprise determining an infrared spectrum of the sample, and determining the hemoglobin concentration of the sample. The hemoglobin concentration and the infrared spectrum can then be used to determine the pH of the sample. In some embodiments, the hemoglobin concentration can be used to select an model relating infrared spectra to pH that is applicable at the determined hemoglobin concentration. In other embodiments, a model relating hemoglobin concentration and infrared spectra to pH can be used. An apparatus according to the present invention can comprise an illumination system, adapted to supply radiation to a sample; a collection system, adapted to collect radiation expressed from the sample responsive to the incident radiation; and an analysis system, adapted to relate information about the incident radiation, the expressed radiation, and the hemoglobin concentration of the sample to pH.

  1. VizieR Online Data Catalog: Four Ae/Be stars map emission at 1mm and 3mm (Boissier+, 2011)

    NASA Astrophysics Data System (ADS)

    Boissier, J.; Alonso-Albi, T.; Fuente, A.; Berne, O.; Bachiller, R.; Neri, R.; Ginard, D.

    We carried out interferometric observations in the continuum around 1.3mm and 3.0mm toward 4 stars: BD+61654, LkHa198, RR Tau, VY Mon. These objects are HAeBe stars with stellar masses of 3 to 7 solar masses located at distances of 600-800pc from the Sun. All the sources were observed in 2008-2009 using the PdBI in different configurations. We make available here the deconvolved (clean) maps constructed from these observations. The units of the map are Jy per Beam. The data reduction was performed using the GILDAS software package. The continuum maps were built summing all the channels free of line emission in the data. Natural weighting has been applied to the measured visibilities. (2 data files).

  2. Power supply switching for a mm-wave asymmetric multilevel outphasing power amplifier system

    E-print Network

    Spaulding, Jonathon David

    2010-01-01

    This thesis demonstrates power switches to be used in our new Asymmetric Multilevel Outphasing (AMO) transmitter architecture at mm-wave frequencies. The AMO topology breaks the linearity vs. efficiency design objective ...

  3. MoSI Habitat Assessment Form Location:___ ___ ___ ___ Station:___ ___ ___ ___ Date:____/____/________ (mm/dd/year) Observers

    E-print Network

    DeSante, David F.

    MoSI Habitat Assessment Form Location:___ ___ ___ ___ Station:___ ___ ___ ___ Date:____/____/________ (mm/dd/year) Observers: Total number of habitat types present:_____ Notes: Habitat Type Letter ____ (from Station Habitat Map) Percent of study area covered by habitat type (determine from Station Habitat

  4. 480mm telephoto perspective, looking south toward midspan and south anchor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    480-mm telephoto perspective, looking south toward mid-span and south anchor arm. - Pittsburgh & Lake Erie Railroad, Ohio River Bridge, Spanning Ohio River, West of Beaver River, Beaver, Beaver County, PA

  5. 480mm telephoto perpective, looking south toward midspan and south anchor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    480-mm telephoto perpective, looking south toward mid-span and south anchor arm. - Pittsburgh & Lake Erie Railroad, Ohio River Bridge, Spanning Ohio River, West of Beaver River, Beaver, Beaver County, PA

  6. Dose distribution around a 3. 0-mm type 6702 I-125 seed

    SciTech Connect

    Scarbrough, E.C. (Department of Radiology University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9071 (USA)); Sanborn, G.E. (Department of Ophthalmology University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9071 (USA)); Anderson, J.A.; Nguyen, P.D. (Department of Radiology University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9071 (USA)); Niederkorn, J.Y. (Department of Ophthalmology University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9071 (USA)); Antich, P.P. (Department of Radiology University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75235-9071 (USA))

    1990-05-01

    The 3M Company recently produced a special version of the type 6702 seed for use in animal studies of ocular melanoma. The seed consists of a single I-125 impregnated ion exchange resin sphere encapsulated in a 3.0-mm-long titanium cylinder, as opposed to the normal 4.5-mm cylinder containing from three to five resin spheres. Monte Carlo simulations and measurements show that the dose distribution around the 3-mm capsule differs in places by up to 10% from that of the 4.5-mm seed. In addition, the two seed types differ by 12% in the ratio of dose in tissue along the transverse seed axis to apparent activity. These differences must be taken into account when using these seeds.

  7. Same-source parallel implementation of the PSU/NCAR MM5

    SciTech Connect

    Michalakes, J.

    1997-12-31

    The Pennsylvania State/National Center for Atmospheric Research Mesoscale Model is a limited-area model of atmospheric systems, now in its fifth generation, MM5. Designed and maintained for vector and shared-memory parallel architectures, the official version of MM5 does not run on message-passing distributed memory (DM) parallel computers. The authors describe a same-source parallel implementation of the PSU/NCAR MM5 using FLIC, the Fortran Loop and Index Converter. The resulting source is nearly line-for-line identical with the original source code. The result is an efficient distributed memory parallel option to MM5 that can be seamlessly integrated into the official version.

  8. SPECIFICATION OF CRATE Standard 6U by 235 mm depth eurocrate without fans and with rear

    E-print Network

    California at Santa Cruz, University of

    SPECIFICATION OF CRATE 1. CRATE Standard 6U by 235 mm depth eurocrate without fans and with rear powerpack (rack will be equiped in fans and cooling system ). 2. CARDS LV and HV cards are single width ( 4

  9. Flocculation of Chlorella vulgaris induced by high pH: role of magnesium and calcium and practical implications.

    PubMed

    Vandamme, Dries; Foubert, Imogen; Fraeye, Ilse; Meesschaert, Boudewijn; Muylaert, Koenraad

    2012-02-01

    Microalgae hold great potential as a feedstock for biofuels or bulk protein or treatment of wastewater or flue gas. Realising these applications will require the development of a cost-efficient harvesting technology. Here, we explore the potential of flocculation induced by high pH for harvesting Chlorella vulgaris. Our results demonstrate that flocculation can be induced by increasing medium pH to 11. Although both calcium and magnesium precipitated when pH was increased, only magnesium (?0.15 mM) proved to be essential to induce flocculation. The costs of four different bases (sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide and sodium carbonate) were calculated and evaluated and the use of lime appeared to be the most cost-efficient. Flocculation induced by high pH is therefore a potentially useful method to preconcentrate freshwater microalgal biomass during harvesting. PMID:22182473

  10. Fixation of mandibular fractures with 2.0-mm miniplates: Review of 191 cases

    Microsoft Academic Search

    Marisa Aparecida Cabrini Gabrielli; Elcio Marcantonio; Eduardo Hochuli-Vieira

    2003-01-01

    Purpose: Our goal was to study the use of 2.0-mm miniplates for the fixation of mandibular fractures. Patients and Methods: Records of 191 patients who experienced a total of 280 mandibular fractures that were treated with 2.0-mm miniplates were reviewed. One hundred twelve of those patients, presenting 160 fractures, who attended a late follow-up were also clinically evaluated. Miniplates were

  11. REMARQUES SUR LE MMOIRE DE MM. NAGAOKA ET HONDA; Par CH.-ED. GUILLAUME.

    E-print Network

    Boyer, Edmond

    621 REMARQUES SUR LE M�MOIRE DE MM. NAGAOKA ET HONDA; Par CH.-ED. GUILLAUME. 11 est facile de voir que le plissement des courbes d'aimantation et d'allongement constaté par MM. Nagaoka et Honda et Honda indique un point singulier des alliages, ou s'il s'agit d'un fait fortuit. J'ajou- terai que

  12. 0.030" Alum T Wire 140 mm Length of No. 12 Wire

    E-print Network

    Allen, Gale

    of T Wire 122mm Long; Form and Solder to N-Connector ~"--I Centerline of Driven Element to Rear Face of N-Connector Brocket Balun: Make from UT-141 Copper-Shielded Coax 340mm All Elements 3/16" Diam 6061 -T6 Solder Lug. Side View Solder Lug Attached to Bottom Screw on Connector, Bent 90° and Soldered to UT-141 Shield Fig

  13. An autonomous 16 mm3 solar-powered node for distributed wireless sensor networks

    Microsoft Academic Search

    Brett A. Warneke; Michael D. Scott; Brian S. Leibowitz; Lixia Zhou; Colby L. Bellew; J. Alex Chediakt; Joseph M. Kahn; Bernhard E. Boser; Kristofer S. J. Pister

    2002-01-01

    A 16 mm3 autonomous solar-powered sensor node with bidirectional optical communication for distributed sensor networks has been demonstrated. The device digitizes integrated sensor signals and transmits\\/receives data over a free-space optical link. The system consists of three die - a 0.25 ?m CMOS ASIC, a 2.6 mm2 SOI solar cell array, and a micromachined four-quadrant corner-cube retroreflector (CCR), allowing it

  14. Can we justify goal blood pressure of <140\\/90 mm hg in most hypertensives?

    Microsoft Academic Search

    Raymond R. Townsend

    2005-01-01

    Hypertension is a common disorder with well-recognized consequences on the heart, brain, and kidney as target organs. Guidelines\\u000a espouse a treatment goal of blood pressure reduction to <140 mm Hg for the systolic pressure and <90 mm Hg for the diastolic\\u000a pressure in most hypertensive patients. In this review, the basis for these recommendations, the practical achievement of\\u000a these goals

  15. Clinical characteristics of papillary thyroid microcarcinoma less than or equal to 5 mm on ultrasonography.

    PubMed

    Lee, Hyoung Shin; Park, Hyo Sang; Kim, Sung Won; Choi, Gwan; Park, Hun-Su; Hong, Jong-Chul; Lee, Sung-Geun; Baek, Seon Mi; Lee, Kang Dae

    2013-11-01

    Management of papillary thyroid microcarcinoma sized ?5 mm identified on ultrasonography is controversial. In this study, we evaluated the clinical characteristics of papillary thyroid microcarcinoma sized ?5 mm on ultrasonography in comparison to those >5 mm and sought to present rationales for optimal management in papillary thyroid microcarcinoma ?5 mm. The medical records of 396 patients who underwent surgery for papillary thyroid carcinoma between 2009 and 2011 were retrospectively analyzed. The patients were grouped into A (?5 mm, n = 132) or B (>5 mm, n = 264) and the clinicopathologic characteristics of the patients were reviewed and compared between the two groups. Tumor capsular invasion (45.5 vs. 59.8 %, p = 0.007) and cervical lymph node metastasis (18.2 vs. 29.2 %, p = 0.018) were more frequent in group B. Nonetheless, group A presented lymph node metastasis in 42.3 % of multifocal cases showing no difference to that of group B (41.5 %, p = 0.946) and also included five cases (3.8 %) of lateral neck metastasis. Multifocality was the only predictive factor for lymph node metastasis in group A (p < 0.001). Over half (55.3 %) of the patients of group A were diagnosed with papillary carcinoma in private clinics; however, only 5.5 % of these patients underwent assessment of lateral neck lymph nodes initially. In conclusion, higher risk of cervical lymph node metastasis should be considered in evaluation and surgical decision of papillary thyroid microcarcinoma ?5 mm identified on ultrasonography with multifocality. Evaluation of the cervical lymph nodes including the lateral neck should not be overlooked when suspicious thyroid nodule suggesting malignancy sized ?5 mm shows multifocal lesions. PMID:23873032

  16. Optical design and evaluation of a 4 mm cost-effective ultra-high-definition arthroscope

    PubMed Central

    Cheng, Dewen; Wang, Yongtian; Yu, Lu; Liu, Xiaohua

    2014-01-01

    High definition and magnification rigid endoscope plays an important role in modern minimally invasive medical surgery and diagnosis. In this paper, we present the design and evaluation methods of a high definition rigid endoscope, specifically an arthroscope, with a large depth of field (DOF). The incident heights and exit angles of the sampled rays on the relay lens are controlled during the optimization process to ensure an effective field view (70°) and a normal ray path within the limited lens diameter of 2.7 mm. The lens is set up as a multi-configuration system with two extreme and one middle object distances to cover a large DOF. As a result, an entrance pupil of 0.3 mm is achieved for the first time, to bring the theoretical resolution to 23.1 lps/mm in the object space at a working distance of 20 mm, with the wavelength of 0.532 um. The modulation transfer function (MTF) curves approach diffraction limit, and the values are all higher than 0.3 at 160 line pairs/mm (lps/mm) in the image space. Meanwhile, stray light caused by total internal reflection on the inner wall of the rod lenses and the objective lens is eliminated. The measured resolution in the object space at a 20 mm working distance is 22.3 lps/mm, and test results show that other performance characteristics also fulfill design requirements. The relay lenses are designed with only one type of the spacer and two types of lenses to greatly reduce the fabrication and assembly cost. The design method has important research and application values for lens systems used in modern minimally invasive medical surgery and industrial non-destructive testing area. PMID:25136495

  17. Regulation of rabbit medullary collecting duct cell pH by basolateral Na+/H+ and Cl-/base exchange.

    PubMed Central

    Breyer, M D; Jacobson, H R

    1989-01-01

    The collecting duct of the inner stripe outer medulla (OMCDi) is a major site of distal nephron acidification. Using the pH sensitive fluorescent dye 2'-7'-bis(carboxyethyl)-5,6,-carboxyfluorescein (BCECF) and quantitative spectrofluorometry to measure intracellular pH in isolated perfused OMCDi, we have characterized basolateral transport processes responsible for regulation of intracellular pH. Experiments suggesting the existence of basolateral Cl-/base exchange were performed. In HCO3- containing buffers, bath Cl- replacement resulted in reversible alkalinization of the OMCDi from 7.22 +/- 0.05 to 7.57 +/- 0.12. Similarly 0.1 mM bath 4',4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS) alkalinized the OMCDi from 7.14 +/- 0.09 to 7.34 +/- 0.09 and blocked further alkalinization by bath Cl- removal (delta = + 0.02 pH units). The concentration dependence kinetics of Cl-/base exchange revealed a K1/2 of 10 mM for external Cl- with a Vmax of 0.50 pH U/min. Experiments suggesting the existence of basolateral Na+/H+ exchange were also performed. Replacement of bath Na+ by tetramethylammonium resulted in reversible cell acidification (7.14 +/- 0.09 to 6.85 +/- 0.1). Tubules that were acidified by a brief exposure to NH4Cl displayed recovery of cell pH back to baseline at a rate that was highly dependent on bath Na+ concentration. Half maximal recovery rate was achieved at 7 mM bath Na+ and Vmax was 0.605 pH U/min. The Na+-dependent rate of cell pH recovery after acidification was blocked by 0.2 mM bath amiloride. These results suggest that intracellular pH in the OMCDi is regulated by parallel basolateral Na+/H+ exchange and Cl-/base exchange. PMID:2547843

  18. Biosorption of U(VI) by the green algae Chlorella vulgaris in dependence of pH value and cell activity

    Microsoft Academic Search

    M. Vogel; A. Günther; A. Rossberg; B. Li; G. Bernhard; J. Raff

    2010-01-01

    Biosorption of uranium(VI) by the green alga Chlorella vulgaris was studied at varying uranium concentrations from 5?M to 1mM, and in the environmentally relevant pH range of 4.4 to 7.0. Living cells bind in a 0.1mM uranium solution at pH 4.4 within 5min 14.3±5.5mgU\\/g dry biomass and dead cells 28.3±0.6mgU\\/g dry biomass which corresponds to 45% and 90% of total

  19. Effects of pH, NH 4 -N concentration, temperature, and storage period on basidiospore germination in an ectomycorrhizal ammonia fungus Hebeloma vinosophyllum

    Microsoft Academic Search

    Zhiqiang Deng; Akira Suzuki

    2008-01-01

    Basidiospore germination in an ectomycorrhizal ammonia fungus Hebeloma vinosophyllum was stimulated by 10–500 mM NH4Cl aqueous solution at pH 4.5–9.0, but not by pure water. The basidiospores germinated at 10°–35°C with an optimum at 25°–30°C.\\u000a The highest germination percentage (83.0%) was observed in 100 mM NH4Cl aqueous solution adjusted to pH 8.0 by KOH, when the basidiospores were incubated at

  20. The effect of ammonium ions and pH on the elaboration of the fungal extracellular polysaccharide, pullulan, by Aureobasidium pullulans

    Microsoft Academic Search

    Marc A. Bulmer; Brian J. Catley; Patrick J. Kelly

    1987-01-01

    Effects of the absence and presence of NH4+(50 mM) and proton concentration (pH range 4–8) on pullulan elaboration by Aureobasidium pullulans have been examined. The action of NH4+is thought to be not as an effector of metabolic pathways, but rather as an influence on protein synthesis. The short-term effect of changes in environmental pH can be dramatic but pullulan elaboration

  1. Forces of interactions between bare and polymer-coated iron and silica: effect of pH, ionic strength, and humic acids.

    PubMed

    Pensini, Erica; Sleep, Brent E; Yip, Christopher M; O'Carroll, Denis

    2012-12-18

    The interactions between a silica substrate and iron particles were investigated using atomic force microscopy-based force spectroscopy (AFM). The micrometer- and nanosized iron particles employed were either bare or coated with carboxymethyl cellulose (CMC), a polymer utilized to stabilize iron particle suspensions. The effect of water chemistry on the forces of interaction was probed by varying ionic strength (with 100 mM NaCl and 100 mM CaCl?) or pH (4, 5.5, and 8) or by introducing 10 mg/L of humic acids (HA). When particles were uncoated, the forces upon approach between silica and iron were attractive at pH 4 and 5.5 and in 100 mM CaCl? at pH 8, but they were negligible in 100 mM NaCl buffered to pH 8 and repulsive in water buffered to pH 8 and in HA solutions. HA produced electrosteric repulsion between iron particles and silica, likely due to its sorption to iron particles. HA sorption to silica was excluded on the basis of experiments conducted with a quartz-crystal microbalance with dissipation monitoring. Repulsion with CMC-coated iron was attributed to electrosteric forces, which were damped at high ionic strength. An extended DLVO model and a modified version of Ohshima's theory were successfully utilized to model AFM data. PMID:23163600

  2. Accuracy of buffered-force QM/MM simulations of silica

    NASA Astrophysics Data System (ADS)

    Peguiron, Anke; Colombi Ciacchi, Lucio; De Vita, Alessandro; Kermode, James R.; Moras, Gianpietro

    2015-02-01

    We report comparisons between energy-based quantum mechanics/molecular mechanics (QM/MM) and buffered force-based QM/MM simulations in silica. Local quantities—such as density of states, charges, forces, and geometries—calculated with both QM/MM approaches are compared to the results of full QM simulations. We find the length scale over which forces computed using a finite QM region converge to reference values obtained in full quantum-mechanical calculations is ˜10 Å rather than the ˜5 Å previously reported for covalent materials such as silicon. Electrostatic embedding of the QM region in the surrounding classical point charges gives only a minor contribution to the force convergence. While the energy-based approach provides accurate results in geometry optimizations of point defects, we find that the removal of large force errors at the QM/MM boundary provided by the buffered force-based scheme is necessary for accurate constrained geometry optimizations where Si-O bonds are elongated and for finite-temperature molecular dynamics simulations of crack propagation. Moreover, the buffered approach allows for more flexibility, since special-purpose QM/MM coupling terms that link QM and MM atoms are not required and the region that is treated at the QM level can be adaptively redefined during the course of a dynamical simulation.

  3. Multiple active zones in hybrid QM/MM molecular dynamics simulations for large biomolecular systems.

    PubMed

    Torras, Juan

    2015-04-01

    A new QM/MM molecular dynamics approach that can deal with the dynamics of large real systems involving several simultaneous active zones is presented. Multiple, unconnected but interacting quantum regions are treated independently in an ordinary QM/MM approach but in a manner which converges to a unique simulation. The multiple active zones in the hybrid QM/MM molecular dynamics methodology (maz-QM/MM MD) involve molecular dynamics that is driving the whole simulation with several parallel executions of energy gradients within the QM/MM approach that merge into each MD step. The Ewald-summation method is used to incorporate long-range electrostatic interactions among the active zones in conjunction with periodic boundary conditions. To illustrate and ascertain capabilities and limitations, we present several benchmark calculations using this approach. Our results show that the maz-QM/MM MD method is able to provide simultaneous treatment of several active zones of very large proteins such as the Cu-4His-?C* cage, a self-assembly of a 24-mer cage-like protein ferritin. PMID:25783778

  4. 5 year Global 3-mm VLBI survey of Gamma-ray active blazars

    E-print Network

    Hodgson, J A; Marscher, A P; Jorstad, S G; Marti-Vidal, I; Lindqvist, M; Bremer, M; Sanchez, S; de Vicente, P; Zensus, J A

    2015-01-01

    The Global mm-VLBI Array (GMVA) is a network of 14 3\\,mm and 7\\,mm capable telescopes spanning Europe and the United States, with planned extensions to Asia. The array is capable of sensitive maps with angular resolution often exceeding 50\\,$\\mu$as. Using the GMVA, a large sample of prominent $\\gamma$-ray blazars have been observed approximately 6 monthly from later 2008 until now. Combining 3\\,mm maps from the GMVA with near-in-time 7\\,mm maps from the VLBA-BU-BLAZAR program and 2\\,cm maps from the MOJAVE program, we determine the sub-pc morphology and high frequency spectral structure of $\\gamma$-ray blazars. The magnetic field strength can be estimated at different locations along the jet under the assumption of equipartition between magnetic field and relativistic particle energies. Making assumptions on the jet magnetic field configuration (e.g. poloidal or toroidal), we can estimate the separation of the mm-wave "core" and the jet base, and estimate the strength of the magnetic field there. The results ...

  5. Influence of Acidic pH on Hydrogen and Acetate Production by an Electrosynthetic Microbiome

    PubMed Central

    LaBelle, Edward V.; Marshall, Christopher W.; Gilbert, Jack A.; May, Harold D.

    2014-01-01

    Production of hydrogen and organic compounds by an electrosynthetic microbiome using electrodes and carbon dioxide as sole electron donor and carbon source, respectively, was examined after exposure to acidic pH (?5). Hydrogen production by biocathodes poised at ?600 mV vs. SHE increased>100-fold and acetate production ceased at acidic pH, but ?5–15 mM (catholyte volume)/day acetate and>1,000 mM/day hydrogen were attained at pH ?6.5 following repeated exposure to acidic pH. Cyclic voltammetry revealed a 250 mV decrease in hydrogen overpotential and a maximum current density of 12.2 mA/cm2 at ?765 mV (0.065 mA/cm2 sterile control at ?800 mV) by the Acetobacterium-dominated community. Supplying ?800 mV to the microbiome after repeated exposure to acidic pH resulted in up to 2.6 kg/m3/day hydrogen (?2.6 gallons gasoline equivalent), 0.7 kg/m3/day formate, and 3.1 kg/m3/day acetate (?=?4.7 kg CO2 captured). PMID:25333313

  6. Algal and Bacterial Activities in Acidic (pH 3) Strip Mine Lakes

    PubMed Central

    Gyure, Ruth A.; Konopka, Allan; Brooks, Austin; Doemel, William

    1987-01-01

    Reservoir 29 and Lake B are extremely acid lakes (epilimnion pHs of 2.7 and 3.2, respectively), because they receive acidic discharges from coal refuse piles. They differ in that the pH of profundal sediments in Reservoir 29 increased from 2.7 to 3.8 during the period of thermal stratification, whereas permanently anoxic sediments in Lake B had a pH of 6.2. The pH rise in Reservoir 29 sediments was correlated with a temporal increase in H2S concentration in the anaerobic hypolimnion from 0 to >1 mM. The chlorophyll a levels in the epilimnion of Reservoir 29 were low, and the rate of primary production was typical of an oligotrophic system. However, there was a dense 10-cm layer of algal biomass at the bottom of the metalimnion. Production by this layer was low owing to light limitation and possibly H2S toxicity. The specific photosynthetic rates of epilimnetic algae were low, which suggests that nutrient availability is more important than pH in limiting production. The highest photosynthetic rates were obtained in water samples incubated at pH 2.7 to 4. Heterotrophic bacterial activity (measured by [14C]glucose metabolism) was greatest at the sediment/water interface. Bacterial production (assayed by thymidine incorporation) was as high in Reservoir 29 as in a nonacid mesotrophic Indiana lake. PMID:16347430

  7. pH recovery from intracellular alkalinization in Retzius neurones of the leech central nervous system.

    PubMed Central

    Frey, G; Schlue, W R

    1993-01-01

    1. Neutral-carrier pH-sensitive microelectrodes were used to investigate intracellular pH (pHi) recovery from alkalinization in leech Retzius neurones in Hepes- and in CO2-HCO3(-)-buffered solution. The Retzius neurones were alkaline loaded by the addition and subsequent removal of 16 mM acetate, by changing from 5% CO2-27 mM HCO3- to 2% CO2-11 mM HCO3- or by changing from CO2-HCO3(-)- to Hepes-buffered solution. 2. In Hepes-buffered solution (pH 7.4) the mean pHi was 7.29 +/- 0.11 and the mean membrane potential -44.7 +/- 5.9 mV (mean +/- S.D.; n = 83). 3. The rate of pHi recovery from alkalinization increased with decreasing pH of the bathing medium (pHb). pHi changed about 0.30 pH units for a pHb unit change. 4. A decrease of extracellular buffer concentration (Hepes concentration lowered from 20 to 5 mM) caused an acidification of extracellular and intracellular pH and an acceleration of pHi recovery from alkalinization. 5. A depolarization of the Retzius cell membrane-induced by increasing the K+ concentration of the bathing medium from 4 to 20 mM (delta Em = 16.5 +/- 5.5 mV) or from 4 to 40 mM (delta Em = 24.8 +/- 3.5 mV)--evoked a decrease of pHi and an acceleration of pHi recovery from alkalinization. 6. The H+ current blocker Zn2+ (0.5 mM) inhibited pHi recovery from alkalinization at resting membrane potential as well as during depolarization. The inhibition was more pronounced during depolarization. 7. In Cl(-)-free, CO2-HCO3(-)-buffered solution pHi recovery from an alkaline load by changing from 5% CO2-27 mM HCO3- to 2% CO2-11 mM HCO3- was slowed by 48-71%. The rate of pHi recovery from an alkaline load induced by changing from CO2-HCO3- to Hepes buffer was reduced by 33-56% in Cl(-)-free solution. The removal of external Cl- did not affect pHi recovery in Hepes-buffered solution. 8. The pHi recovery from alkalinization was DIDS-insensitive in CO2-HCO3(-)- as in Hepes-buffered solutions and was not slowed in the absence of external Na+. 9. It is concluded that in Retzius neurones pHi recovery from alkalinization is mediated by a passive voltage-dependent H+ influx along the electrochemical proton gradient. In the presence of CO2-HCO3- buffer a DIDS-insensitive Cl(-)-HCO3- exchanger additionally regulates pHi after an intracellular alkaline load. It cannot be excluded that intracellular processes (e.g. H+ release from organelles, metabolic H+ production) are also involved in pHi recovery from alkalinization. PMID:8331595

  8. The Effect of Acidic pH on Microleakage of Mineral Trioxide Aggregate and Calcium-Enriched Mixture Apical Plugs

    PubMed Central

    Mirhadi, Hossein; Moazzami, Fariborz; Safarzade, Sareh

    2014-01-01

    Introduction: The purpose of this laboratory study was to evaluate the effect of acidic pH on the sealing ability of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA) apical plugs. Methods and Materials: Seventy single-rooted human maxillary anterior teeth were recruited. The teeth were randomly divided into 4 experimental groups (n=15), and 1 negative and 1 positive control groups of 5. The root canals were cleaned and shaped and the terminal 3 mm of the roots were resected. Then MTA and CEM cement plugs were condensed in apical region with 3 mm thicknesses. The samples were exposed to pH values of 5.5 and 7.4. Leakage was evaluated by the fluid filtration technique at 1, 7, 14, 30 day intervals. Data were analyzed by the repeated measures MANOVA, one-way ANOVA and MANOVA/Bonferroni test. Results: Acidic pH significantly reduced the sealing ability of MTA after 1, 14 and 30 days (P<0.05). The rate of microleakage in CEM cement samples in acidic pH was significantly greater than that in neutral pH in day 30 (P<0.05). There was no significant difference between the sealing property of MTA and CEM cement at both pH levels (P>0.05). Conclusion: It can be concluded that the CEM cement exhibited similar sealing ability as MTA at both pH levels. In addition, an acidic pH environment reduced the sealing ability of MTA and CEM cement after 30 days. PMID:25386205

  9. Solution pH that minimizes self-association of three monoclonal antibodies is strongly dependent on ionic strength.

    PubMed

    Sule, Shantanu V; Cheung, Jason K; Antochshuk, Valentyn; Bhalla, Amardeep S; Narasimhan, Chakravarthy; Blaisdell, Steven; Shameem, Mohammed; Tessier, Peter M

    2012-04-01

    Monoclonal antibodies display highly variable solution properties such as solubility and viscosity at elevated concentrations (>50 mg/mL), which complicates antibody formulation and delivery. To understand this complex behavior, it is critical to measure the underlying protein self-interactions that govern the solution properties of antibody suspensions. We have evaluated the pH-dependent self-association behavior of three monoclonal antibodies using self-interaction chromatography for a range of pH values commonly used in antibody formulations (pH 4.4-6). At low ionic strength (<25 mM), we find that each antibody is more associative at near-neutral pH (pH 6) than at low pH (pH 4.4). At high ionic strength (>100 mM), we observe the opposite pH-dependent pattern of antibody self-association. Importantly, this inversion in self-association behavior is not unique to multidomain antibodies, as similar pH-dependent behavior is observed for some small globular proteins (e.g., ribonuclease A and ?-chymotrypsinogen). We also find that the opalescence of concentrated antibody solutions (90 mg/mL) is minimized at low ionic strength at pH 4.4 and high ionic strength at pH 6, in agreement with the self-interaction measurements conducted at low antibody concentrations (5 mg/mL). Our results highlight the complexity of antibody self-association and emphasize the need for systematic approaches to optimize the solution properties of concentrated antibody formulations. PMID:22221144

  10. MM Caregiver Grief Inventory -Short Form Thomas M. Meuser, Ph.D., University of Missouri St. Louis Samuel J. Marwit, Ph.D., University of Missouri-St. Louis (Emeritus)

    E-print Network

    = Strongly Agree). It is important that you respond to all items so that the scores are accurate. Scoring of each score to guide you. Personal Sacrifice Burden (A Items) = __________ (6 Items, M = 20.2, SD = 5 High 25 20 Average 15 10 5 Low 0 Personal Sacrifice Heartfelt Sadness Worry & Burden & Longing Felt

  11. M.S. and Ph.D. in Environmental

    E-print Network

    Chapman, Michael S.

    , or business. Ph.D. Degree The Ph.D. in ESE prepares students for careers in academic research, teaching genomics and proteomics, and computer modeling and simulation. Collaborations within OHSU's Institute, Ph.D. Marine Biotechnology Richard Johnson, Ph.D. Contaminant Hydrology Joseph Needoba, Ph.D. Marine

  12. Summary PhD candidate satisfaction survey 2011 Introduction

    E-print Network

    Utrecht, Universiteit

    1 Summary PhD candidate satisfaction survey 2011 Introduction Nine years ago, Utrecht University asked its PhD candidates to rate a number of aspects of their PhD careers: were they on schedule; what completing their PhDs. Nine years later, a second survey is conducted on PhD candidate satisfaction

  13. Metabolism and disposition of MM-433593, a selective FAAH-1 inhibitor, in monkeys

    PubMed Central

    Banijamali, Ali R; Wakefield, James D; Mermerian, Ara H; Busby, Robert W

    2014-01-01

    MM-433593 is a highly potent and selective inhibitor of fatty acid amide hydrolase-1 (FAAH-1) with potential utility as an orally administered treatment of pain, inflammation, and other disorders. In this study, we investigated the metabolism and pharmacokinetics of MM-433593 in monkeys, and compared plasma and urine metabolites of this compound to the in vitro metabolites produced by monkey hepatocytes. Intravenous administration of MM-433593 to cynomolgus monkeys produced a rapid distribution phase and slower elimination phase with a mean systemic clearance rate of 8–11 mL/min/kg. Absolute oral bioavailability was determined to be 14–21% with maximum plasma concentrations reached ?3 h (Tmax) following a 10 mg/kg oral dose. The average terminal half-life of MM-433593 was 17–20 h, and there were no qualitative sex differences in the metabolite profile of MM-433593. The major site of metabolism was oxidation of the methyl group at the five position of the indole ring, which was confirmed by chromatography and mass spectrometry comparison to a synthesized authentic standard. This metabolite was further oxidized to the corresponding carboxylic acid and/or conjugated with sulfate, glucuronide, or glutathione. In all, 18 metabolites were found in plasma and urine. In vitro incubations of MM-433593 with monkey hepatocytes yielded 13 metabolites, all of which were found in vivo, indicating a good correlation between the in vitro and in vivo metabolism data. A comprehensive pathway for the metabolism of MM-433593 is proposed, including a plausible, five-step biotransformation for the formation of N-acetylcysteine conjugate metabolite (M18) from the hydroxylated parent (M5). PMID:25505606

  14. Depth Penetration and Detection of pH Gradients in Biofilms by Two-Photon Excitation Microscopy

    PubMed Central

    Vroom, Jurrien M.; De Grauw, Kees J.; Gerritsen, Hans C.; Bradshaw, David J.; Marsh, Philip D.; Watson, G. Keith; Birmingham, John J.; Allison, Clive

    1999-01-01

    Deep microbial biofilms are a major problem in many industrial, environmental, and medical settings. Novel approaches are needed to understand the structure and metabolism of these biofilms. Two-photon excitation microscopy (TPE) and conventional confocal laser scanning microscopy (CLSM) were compared quantitatively for the ability to visualize bacteria within deep in vitro biofilms. pH gradients within these biofilms were determined by fluorescence lifetime imaging, together with TPE. A constant-depth film fermentor (CDFF) was inoculated for 8 h at 50 ml · h?1 with a defined mixed culture of 10 species of bacteria grown in continuous culture. Biofilms of fixed depths were developed in the CDFF for 10 or 11 days. The microbial compositions of the biofilms were determined by using viable counts on selective and nonselective agar media; diverse mixed-culture biofilms developed, including aerobic, facultative, and anaerobic species. TPE was able to record images four times deeper than CLSM. Importantly, in contrast to CLSM images, TPE images recorded deep within the biofilm showed no loss of contrast. The pH within the biofilms was measured directly by means of fluorescence lifetime imaging; the fluorescence decay of carboxyfluorescein was correlated with biofilm pH and was used to construct a calibration curve. pH gradients were detectable, in both the lateral and axial directions, in steady-state biofilms. When biofilms were overlaid with 14 mM sucrose for 1 h, distinct pH gradients developed. Microcolonies with pH values of below pH 3.0 were visible, in some cases adjacent to areas with a much higher pH (>5.0). TPE allowed resolution of images at significantly greater depths (as deep as 140 ?m) than were possible with CLSM. Fluorescence lifetime imaging allowed the in situ, real-time imaging of pH and the detection of sharp gradients of pH within microbial biofilms. PMID:10427041

  15. Synergistic and Antagonistic Effects of Salinity and pH on Germination in Switchgrass (Panicum virgatum L.)

    PubMed Central

    Liu, Yuan; Wang, Quanzhen; Zhang, Yunwei; Cui, Jian; Chen, Guo; Xie, Bao; Wu, Chunhui; Liu, Haitao

    2014-01-01

    The effects of salt-alkaline mixed stress on switchgrass were investigated by evaluating seed germination and the proline, malondialdehyde (MDA) and soluble sugar contents in three switchgrass (Panicum virgatum L.) cultivars in order to identify which can be successfully produced on marginal lands affected by salt-alkaline mixed stress. The experimental conditions consisted of four levels of salinity (10, 60, 110 and 160 mM) and four pH levels (7.1, 8.3, 9.5 and 10.7). The effects of salt-alkaline mixed stress with equivalent coupling of the salinity and pH level on the switchgrass were explored via model analyses. Switchgrass was capable of germinating and surviving well in all treatments under low-alkaline pH (pH?8.3), regardless of the salinity. However, seed germination and seedling growth were sharply reduced at higher pH values in conjunction with salinity. The salinity and pH had synergetic effects on the germination percentage, germination index, plumular length and the soluble sugar and proline contents in switchgrass. However, these two factors exhibited antagonistic effects on the radicular length of switchgrass. The combined effects of salinity and pH and the interactions between them should be considered when evaluating the strength of salt-alkaline mixed stress. PMID:24454834

  16. Roadmap: Public Health Pre-Medicine Bachelor of Science in Public Health [PH-BSPH-PH-PMD

    E-print Network

    Sheridan, Scott

    Roadmap: Public Health ­ Pre-Medicine ­Bachelor of Science in Public Health [PH and 10120 PH 30004 Public Health Research 3 PH 30007 Prevention and Control of Diseases 3 PHY 13001 Health ­ Pre-Medicine ­Bachelor of Science in Public Health [PH-BSPH-PH-PMD] College of Public Health

  17. Nadarajen A. Vydelingum, PhD

    Cancer.gov

    Division of Cancer Prevention Staff Nadarajen A. Vydelingum, PhD Biologist and Program DirectorCancer Biomarkers Research Group Location Division of Cancer PreventionNational Cancer Institute9609 Medical Center Drive, Room 5E604 Rockville, MD

  18. Vance W. Berger, PhD

    Cancer.gov

    Division of Cancer Prevention Staff Vance W. Berger, PhD Mathematical StatisticianBiometry Research Group Location Division of Cancer PreventionNational Cancer Institute9609 Medical Center Drive, Room 5E628 Rockville, MD 20850 Phone

  19. Paul Pinsky, PhD, MPH

    Cancer.gov

    Division of Cancer Prevention Staff Paul Pinsky, PhD, MPH Acting ChiefEarly Detection Research Group Location Division of Cancer PreventionNational Cancer Institute9609 Medical Center Drive, Room 5E444 Rockville, MD 20850 Phone

  20. Mary Fennell, PhD Chair

    Cancer.gov

    NCI Community Cancer Centers Program Evaluation Oversight Committee Roster CHAIR Mary Fennell, Ph.D. Chair, Department of Sociology and Community Health Brown University Box 1916, 211 Maxcy Hall 112 George Street Providence, RI 02912

  1. pH- and temperature-sensitive polymeric microspheres for drug delivery: the dissolution of copolymers modulates drug release.

    PubMed

    Fundueanu, Gheorghe; Constantin, Marieta; Stanciu, Cristina; Theodoridis, Georgios; Ascenzi, Paolo

    2009-12-01

    Most pH-/temperature-responsive polymers for controlled release of drugs are used as cross-linked hydrogels. However, the solubility properties of the linear polymers below and above the lower critical solution temperature (LCST) are not exploited. Here, the preparation and characterization of poly (N-isopropylacrylamide-co-methacrylic acid-co-methyl methacrylate) (poly (NIPAAm-co-MA-co-MM)) and poly (N-isopropylacrylamide-co-acrylamide) (poly (NIPAAm-co-AAm)), known as "smart" polymers (SP), is reported. Both poly (NIPAAm-co-MA-co-MM) and poly (NIPAAm-co-AAm) display pH- and temperature-responsive properties. Poly (NIPAAm-co-MA-co-MM) was designed to be insoluble in the gastric fluid (pH = 1.2), but soluble in the intestinal fluid (pH = 6.8 and 7.4), at the body temperature (37 degrees C). Poly (NIPAAm-co-AAm) was designed to have a lower critical solution temperature (LCST) corresponding to 37 degrees C at pH = 7.4, therefore it is not soluble above the LCST. The solubility characteristics of these copolymers were exploited to modulate the rate of release of drugs by changing pH and/or temperature. These copolymers were solubilized with hydrophobic cellulose acetate butyrate (CAB) and vitamin B(12) (taken as a water soluble drug model system) in an acetone/methanol mixture and dispersed in mineral oil. By a progressive evaporation of the solvent, the liquid droplets were transformed into loaded CAB/SP microspheres. Differential scanning calorimetric studies and scanning electron microscopy analysis demonstrated that the polymeric components of the microspheres precipitated separately during solvent evaporation forming small microdomains. Moreover, vitamin B(12) was found to be molecularly dispersed in both microdomains with no specific affinity for any polymeric component of microspheres. The release of vitamin B(12) was investigated as a function of temperature, pH, and the CAB/SP ratio. PMID:19562468

  2. QM/MM Minimum Free Energy Path: Methodology and Application to Triosephosphate Isomerase.

    PubMed

    Hu, Hao; Lu, Zhenyu; Yang, Weitao

    2007-03-01

    Structural and energetic changes are two important characteristic properties of a chemical reaction process. In the condensed phase, studying these two properties is very challenging because of the great computational cost associated with the quantum mechanical calculations and phase space sampling. Although the combined quantum mechanics/molecular mechanics (QM/MM) approach significantly reduces the amount of the quantum mechanical calculations and facilitates the simulation of solution phase and enzyme catalyzed reactions, the required quantum mechanical calculations remain quite expensive and extensive sampling can be achieved routinely only with semiempirical quantum mechanical methods. QM/MM simulations with ab initio QM methods, therefore, are often restricted to narrow regions of the potential energy surface such as the reactant, product and transition state, or the minimum energy path. Such ab initio QM/MM calculations have previously been performed with the QM/MM-Free Energy (QM/MM-FE) method of Zhang et al.1 to generate the free energy profile along the reaction coordinate using free energy perturbation calculations at fixed structures of the QM subsystems. Results obtained with the QM/MM-FE method depend on the determination of the minimum energy reaction path, which is based on local conformations of the protein/solvent environment and can be difficult to obtain in practice. To overcome the difficulties associated with the QM/MM-FE method and to further enhance the sampling of the MM environment conformations, we develop here a new method to determine the QM/MM minimum free energy path (QM/MM-MFEP) for chemical reaction processes in solution and in enzymes. Within the QM/MM framework, we express the free energy of the system as a function of the QM conformation, thus leading to a simplified potential of mean force (PMF) description for the thermodynamics of the system. The free energy difference between two QM conformations is evaluated by the QM/MM free energy perturbation method. The free energy gradients with respect to the QM degrees of freedom are calculated from molecular dynamics simulations at given QM conformations. With the free energy and free energy gradients in hand, we further implement chain-of-conformation optimization algorithms in the search for the reaction path on the free energy surface without specifying a reaction coordinate. This method thus efficiently provides a unique minimum free energy path for solution and enzyme reactions, with structural and energetic properties being determined simultaneously. To further incorporate the dynamic contributions of the QM subsystem into the simulations, we develop the reaction path potential of Lu, et al.2 for the minimum free energy path. The combination of the methods developed here presents a comprehensive and accurate treatment for the simulation of reaction processes in solution and in enzymes with ab initio QM/MM methods. The method has been demonstrated on the first step of the reaction of the enzyme triosephosphate isomerase with good agreement with previous studies. PMID:19079734

  3. Development and application of QM/MM methods to study the solvation effects and surfaces

    SciTech Connect

    Dibya, Pooja Arora

    2010-05-16

    Quantum mechanical (QM) calculations have the advantage of attaining high-level accuracy, however QM calculations become computationally inefficient as the size of the system grows. Solving complex molecular problems on large systems and ensembles by using quantum mechanics still poses a challenge in terms of the computational cost. Methods that are based on classical mechanics are an inexpensive alternative, but they lack accuracy. A good trade off between accuracy and efficiency is achieved by combining QM methods with molecular mechanics (MM) methods to use the robustness of the QM methods in terms of accuracy and the MM methods to minimize the computational cost. Two types of QM combined with MM (QM/MM) methods are the main focus of the present dissertation: the application and development of QM/MM methods for solvation studies and reactions on the Si(100) surface. The solvation studies were performed using a discreet solvation model that is largely based on first principles called the effective fragment potential method (EFP). The main idea of combining the EFP method with quantum mechanics is to accurately treat the solute-solvent and solvent-solvent interactions, such as electrostatic, polarization, dispersion and charge transfer, that are important in correctly calculating solvent effects on systems of interest. A second QM/MM method called SIMOMM (surface integrated molecular orbital molecular mechanics) is a hybrid QM/MM embedded cluster model that mimics the real surface.3 This method was employed to calculate the potential energy surfaces for reactions of atomic O on the Si(100) surface. The hybrid QM/MM method is a computationally inexpensive approach for studying reactions on larger surfaces in a reasonably accurate and efficient manner. This thesis is comprised of four chapters: Chapter 1 describes the general overview and motivation of the dissertation and gives a broad background of the computational methods that have been employed in this work. Chapter 2 illustrates the methodology of the interface of the EFP method with the configuration interaction with single excitations (CIS) method to study solvent effects in excited states. Chapter 3 discusses the study of the adiabatic electron affinity of the hydroxyl radical in aqueous solution and in micro-solvated clusters using a QM/EFP method. Chapter 4 describes the study of etching and diffusion of oxygen atom on a reconstructed Si(100)-2 x 1 surface using a hybrid QM/MM embedded cluster model (SIMOMM). Chapter 4 elucidates the application of the EFP method towards the understanding of the aqueous ionization potential of Na atom. Finally, a general conclusion of this dissertation work and prospective future direction are presented in Chapter 6.

  4. Use of 5-mm-diameter implants: Periotest values related to a clinical and radiographic evaluation.

    PubMed

    Aparicio, C; Orozco, P

    1998-12-01

    A modified design of the original Brånemark implant consisting of a cp. Titanium 5.0-mm-diameter self-tapping implant threaded up to the marginal platform has been proposed for specific indications. From February 1992 to November 1995, a total of 185 machined screw implants (Nobel Biocare, Gothenburg, Sweden) were installed in 45 patients to withstand 58 prostheses. Of these, 91 were 3.75-mm diameter and 94 were 5.0-mm wide. Most of the implants were placed in type B and C bone quantity and type 2 and 3 bone quality. A retrospective evaluation with regard to indications, marginal bone remodelling, Periotest values (PTv) and survival rate is presented. PTv and radiographic measurements were made at abutment connection and repeated 3, 6 and 12 months later and thereafter every year. The follow-up ranged from 16 to 55 months (mean 32.9 months) post-loading. Three patients with 8 5.0-mm implants dropped-out of the study at different stages. Out of the wide implants, 1 was expelled during the healing period; 3 were found mobile at the abutment connection; 1 lost its osseointegration suddenly after 2 years of function; 4 belonging to 1 patient did not meet the success criteria due to continuous marginal bone loss. The cumulative success rate of 5.0-mm implants (CSR) after 1 year of function was 97.2% for upper jaws and 88.4% in mandibles, whereas the CSR in maxilla after 48 months was 97.2% and 83.4% in mandibles. The obtained PTv from 5.0-mm-wide fixtures in maxilla and mandibles were respectively 1.1 and 0.6 units lower than those obtained PTv for 3.75-mm-diameter implants in the same patients. The hypothesis that there are differences in the damping capacity of the bone surrounding a 5.0-mm-wide implant compared to the 3.75-mm-diameter implant is supported by the PTv results. PMID:11429941

  5. Effects of pH, Chloride, and Bicarbonate on Cu(I) Oxidation Kinetics at Circumneutral pH

    NASA Astrophysics Data System (ADS)

    Yuan, X.; Pham, A.; Waite, T.; Xing, G.; Rose, A.

    2012-12-01

    The redox chemistry of copper species in the upper water column plays a significant role in its speciation, transport and bioavailability. Most previous studies have focused primarily on Cu(II), principally because Cu(I) is easily oxidized to Cu(II) by oxygen or other oxidants. However, a growing body of evidence indicates that a number of potentially important reactions may lead to Cu(I) formation and result in a significant steady-state concentration of Cu(I) in natural waters. Redox reactions of Cu(I) could result in the production of reactive oxygen species (ROS), such as superoxide and hydroxyl radical, that may subsequently induce a cascade of radical-promoted reactions with other constituents in natural waters. As such, a better understanding of copper-catalysed processes that produce and consume O2- is important in furthering our insight into factors contributing to global biogeochemical cycles. In this study, the oxidation kinetics of nanomolar concentrations of Cu(I) in NaCl solutions have been investigated over the pH range 6.5-8.0.The overall apparent oxidation rate constant was strongly affected by chloride, moderately by bicarbonate and, and to a lesser extent, by pH. In the absence of bicarbonate, an equilibrium-based speciation model indicated that Cu+ and CuClOH- were the most kinetically reactive species, while the contribution of other Cu(I) species to the overall oxidation rate was minor. A kinetic model based on recognized key redox reactions for these two species further indicated that oxidation of Cu(I) by oxygen and superoxide were important reactions at all pH values and [Cl-] considered, but back reduction of Cu(II) by superoxide only became important at relatively low chloride concentrations. Bicarbonate concentrations from 2-5 mM substantially accelerated Cu(I) oxidation. Kinetic analysis over a range of bicarbonate concentrations revealed that this was due to the formation of CuCO3-, which reacts relatively rapidly with oxygen, and not due to inhibition of the back reduction of Cu(II) by formation of Cu(II)-carbonate complexes. We conclude that the simultaneous oxygenation of Cu+, CuClOH- and CuCO3- is the rate-limiting step in the overall oxidation of Cu(I) under these conditions. Determination of values for apparent and intrinsic rate constants for the oxidation of those critical Cu(I) species by O2 over the pH range 6.5-8.0 should greatly assist in understanding and predicting inorganic Cu(I) and Cu(II) transformations in natural waters.

  6. POLYVIEW-MM: web-based platform for animation and analysis of molecular simulations

    PubMed Central

    Porollo, Aleksey; Meller, Jaroslaw

    2010-01-01

    Molecular simulations offer important mechanistic and functional clues in studies of proteins and other macromolecules. However, interpreting the results of such simulations increasingly requires tools that can combine information from multiple structural databases and other web resources, and provide highly integrated and versatile analysis tools. Here, we present a new web server that integrates high-quality animation of molecular motion (MM) with structural and functional analysis of macromolecules. The new tool, dubbed POLYVIEW-MM, enables animation of trajectories generated by molecular dynamics and related simulation techniques, as well as visualization of alternative conformers, e.g. obtained as a result of protein structure prediction methods or small molecule docking. To facilitate structural analysis, POLYVIEW-MM combines interactive view and analysis of conformational changes using Jmol and its tailored extensions, publication quality animation using PyMol, and customizable 2D summary plots that provide an overview of MM, e.g. in terms of changes in secondary structure states and relative solvent accessibility of individual residues in proteins. Furthermore, POLYVIEW-MM integrates visualization with various structural annotations, including automated mapping of known inter-action sites from structural homologs, mapping of cavities and ligand binding sites, transmembrane regions and protein domains. URL: http://polyview.cchmc.org/conform.html. PMID:20504857

  7. Survival and growth of age-0 steelhead after surgical implantation of 23-mm passive integrated transponders

    USGS Publications Warehouse

    Bateman, D.S.; Gresswell, R.E.

    2006-01-01

    Little information is available on the effects of implanting 23-mm passive integrated transponder (PIT) tags in salmonids less than 90 mm fork length (FL). Using juvenile steelhead Oncorhynchus mykiss (range, 73-97 mm FL), we compared instantaneous growth rates and survival among three experimental groups: control, surgery with no tag, and surgery with tag. Survival rate was lower for tagged fish (86%) than for control and surgery-no tag fish (virtually 100% in each group). Approximately 90% of the mortalities occurred during days 1-3. Growth rate for the tagged group was lower for the first two 10-d measurement intervals; however, during the third 10-d interval, growth rates for tagged fish equaled or exceeded values for the other groups. These results suggest that tagged fish recovered by day 20. Growth rates for the control and surgery-no tag groups did not differ from one another during any measurement interval. Tag retention rate was 97% over the 30-d period of the study. It appears that the combination of fish length and tag size in this study resulted in short-term negative effects on growth rate and survival; however, 23-mm PIT tags may still be useful for studies of salmonids 80-90 mm FL when survival is not the parameter of interest. ?? Copyright by the American Fisheries Society 2006.

  8. Ultra-Compact Multitip Scanning Probe Microscope with an Outer Diameter of 50 mm

    NASA Astrophysics Data System (ADS)

    Cherepanov, Vasily; Zubkov, Evgeny; Junker, Hubertus; Korte, Stefan; Blab, Marcus; Coenen, Peter; Voigtländer, Bert

    We present a multitip scanning tunneling microscope (STM) where four independent STM units are integrated on a diameter of 50 mm. The coarse positioning of the tips is done under the control of an optical microscope or an SEM in vacuum. The heart of this STM is a new type of piezoelectric coarse approach called Koala Drive which can have a diameter greater than 2.5 mm and a length smaller than 10 mm. Alternating movements of springs move a central tube which holds the STM tip or AFM sensor. This new operating principle provides a smooth travel sequence and avoids shaking which is intrinsically present for nanopositioners based on inertial motion with saw tooth driving signals. Inserting the Koala Drive in a piezo tube for xyz-scanning integrates a complete STM inside a 4 mm outer diameter piezo tube of <10 mm length. The use of the Koala Drive makes the scanning probe microscopy design ultra-compact and accordingly leads to a high mechanical stability. The drive is UHV, low temperature, and magnetic field compatible. The compactness of the Koala Drive allows building a four-tip STM as small as a single-tip STM with a drift of <0.2 nm/min and lowest resonance frequencies of 2.5 (xy) and 5.5 kHz (z). We present examples of the performance of the multitip STM designed using the Koala Drive.

  9. Fourier transform infrared absorption spectroscopy characterization of gaseous atmospheric pressure plasmas with 2 mm spatial resolution

    SciTech Connect

    Laroche, G. [Laboratoire d'Ingenierie de Surface, Centre de Recherche sur les Materiaux Avances, Departement de genie des mines, de la metallurgie et des materiaux, Universite Laval, 1065, avenue de la Medecine, Quebec G1V 0A6 (Canada); Centre de recherche du CHUQ, Hopital St Francois d'Assise, 10, rue de l'Espinay, local E0-165, Quebec G1L 3L5 (Canada); Vallade, J. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Agence de l'environnement et de la Ma Latin-Small-Letter-Dotless-I -carettrise de l'Energie, 20, avenue du Gresille, BP 90406, F-49004 Angers Cedex 01 (France); Bazinette, R.; Hernandez, E.; Hernandez, G.; Massines, F. [Laboratoire Procedes, Materiaux et Energie Solaire, PROMES, CNRS, Technosud, Rambla de la Thermodynamique, F-66100 Perpignan (France); Nijnatten, P. van [OMT Solutions bv, High Tech Campus 9, 5656AE Eindhoven (Netherlands)

    2012-10-15

    This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm Multiplication-Sign 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45 Degree-Sign beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma.

  10. Fourier transform infrared absorption spectroscopy characterization of gaseous atmospheric pressure plasmas with 2 mm spatial resolution.

    PubMed

    Laroche, G; Vallade, J; Bazinette, R; van Nijnatten, P; Hernandez, E; Hernandez, G; Massines, F

    2012-10-01

    This paper describes an optical setup built to record Fourier transform infrared (FTIR) absorption spectra in an atmospheric pressure plasma with a spatial resolution of 2 mm. The overall system consisted of three basic parts: (1) optical components located within the FTIR sample compartment, making it possible to define the size of the infrared beam (2 mm × 2 mm over a path length of 50 mm) imaged at the site of the plasma by (2) an optical interface positioned between the spectrometer and the plasma reactor. Once through the plasma region, (3) a retro-reflector module, located behind the plasma reactor, redirected the infrared beam coincident to the incident path up to a 45° beamsplitter to reflect the beam toward a narrow-band mercury-cadmium-telluride detector. The antireflective plasma-coating experiments performed with ammonia and silane demonstrated that it was possible to quantify 42 and 2 ppm of these species in argon, respectively. In the case of ammonia, this was approximately three times less than this gas concentration typically used in plasma coating experiments while the silane limit of quantification was 35 times lower. Moreover, 70% of the incoming infrared radiation was focused within a 2 mm width at the site of the plasma, in reasonable agreement with the expected spatial resolution. The possibility of reaching this spatial resolution thus enabled us to measure the gaseous precursor consumption as a function of their residence time in the plasma. PMID:23126767

  11. The implementation of a fast and accurate QM/MM potential method in Amber.

    PubMed

    Walker, Ross C; Crowley, Michael F; Case, David A

    2008-05-01

    Version 9 of the Amber simulation programs includes a new semi-empirical hybrid QM/MM functionality. This includes support for implicit solvent (generalized Born) and for periodic explicit solvent simulations using a newly developed QM/MM implementation of the particle mesh Ewald (PME) method. The code provides sufficiently accurate gradients to run constant energy QM/MM MD simulations for many nanoseconds. The link atom approach used for treating the QM/MM boundary shows improved performance, and the user interface has been rewritten to bring the format into line with classical MD simulations. Support is provided for the PM3, PDDG/PM3, PM3CARB1, AM1, MNDO, and PDDG/MNDO semi-empirical Hamiltonians as well as the self-consistent charge density functional tight binding (SCC-DFTB) method. Performance has been improved to the point where using QM/MM, for a QM system of 71 atoms within an explicitly solvated protein using periodic boundaries and PME requires less than twice the cpu time of the corresponding classical simulation. PMID:18072177

  12. IMPEE PhD Opportunity Project title: LightFoot PhD A PhD Investigation Lightning Protection of HV Overhead Lines with Non-Ideal

    E-print Network

    Greenaway, Alan

    IMPEE PhD Opportunity Project title: LightFoot PhD ­ A PhD Investigation Lightning Protection of HV.swingler@hw.ac.uk Abstract LightFoot PhD ­ A PhD Investigation Lightning Protection of HV Overhead Lines with Non-Ideal Tower to the understanding of the effect of lightning strikes on an overhead transmission line in terms of its electrical

  13. Cognitive Science Program PhD and Joint PhD Timeline PhD = Single major w/ CogSci as Home dept;

    E-print Network

    Indiana University

    Cognitive Science Program PhD and Joint PhD Timeline PhD = Single major w/ CogSci as Home dept; PhD Joint = Dual Major w/ CogSci as Home Dept Joint PhD = Dual Major w/ CogSci NOT as Home Dept. KEY: AC=Advisory Committee; DGS= Director of Graduate Studies; UGS = University Graduate School Timing Events Forms Required

  14. Gas phase ion chemistry and ab initio theoretical study of phosphine. III. Reactions of PH2+ and PH3+ with PH3

    NASA Astrophysics Data System (ADS)

    Antoniotti, Paola; Operti, Lorenza; Rabezzana, Roberto; Tonachini, Glauco; Vaglio, Gian Angelo

    2000-01-01

    The gas phase ion chemistry of phosphine has been investigated by ab initio theoretical calculations and experimental techniques. Following previous studies dealing with 3P+ and PH+ reacting with PH3, the quantum chemical study of these processes has been extended to the ion/molecule reactions starting from PH2+ and PH3 (reaction a) or PH3+ and PH3 (reaction b), as observed by ion trapping. In these experiments, PH2+ reacts to give P2Hn+ (n=1,3) product ions, with loss of H2 through different pathways. These processes take place at quite different rates, their constants being 2.6 and 7.6×10-10 cm3 molecule-1 s-1, respectively. The geometrical structures and energies of transition structures, reaction intermediates, and final products have been determined by ab initio theoretical methods. The initial step of the reaction of PH2+ with PH3 is formation of the H2P-PH3+ adduct. Then, a hydrogen molecule can be directly lost either from tricoordinated or tetracoordinated phosphorus, to give P-PH3+ or HP=PH2+, respectively. The shift of one H atom in HP=PH2+ produces the bridged HP(H)PH+ ion, from which further dissociation of H2 yields PPH+. The initial step of the reaction of PH3+ with PH3 is formation of the H3P-PH3+ adduct. Then inversion of the H atoms in the PH3 group transforms the adduct in an electrostatic complex. This last species is related by a dissociation process to the PH2 and PH4+ products. The heats of formation of the P2Hn+ (n=1-6) ionic species have been computed and compared with the experimental data in the literature.

  15. Effects of starvation on the transport of Escherichia coli K12 in saturated porous media are dependent on pH and ionic strength

    NASA Astrophysics Data System (ADS)

    Xu, S.; Walczak, J. J.; Wang, L.; Bardy, S. L.; Li, J.

    2010-12-01

    In this research, we investigate the effects of starvation on the transport of E. coli K12 in saturated porous media. Particularly, we examine the relationship between such effects and the pH and ionic strength of the electrolyte solutions that were used to suspend bacterial cells. E. coli K12 (ATCC 10798) cells were cultured using either Luria-Bertani Miller (LB-Miller) broth (10 g trypton, 5 g yeast extract and 10 g NaCl in 1 L of deionized water) or LB-Luria broth (10 g tryptone, 5 g yeast extract and 0.5 g NaCl in 1 L of deionized water). Both broths had similar pH (~7.1) but differed in ionic strength (LB-Miller: ~170 mM, LB-Luria: ~ 8 mM). The bacterial cells were then harvested and suspended using one of the following electrolyte solutions: phosphate buffered saline (PBS) (pH ~7.2; ionic strength ~170 mM), 168 mM NaCl (pH ~5.7), 5% of PBS (pH ~ 7.2; ionic strength ~ 8 mM) and 8 mM NaCl (pH ~ 5.7). Column transport experiments were performed at 0, 21 and 48 hours following cell harvesting to evaluate the change in cell mobility over time under “starvation” conditions. Our results showed that 1) starvation increased the mobility of E. coli K12 cells; 2) the most significant change in mobility occurred when bacterial cells were suspended in an electrolyte solution that had different pH and ionic strength (i.e., LB-Miller culture suspended in 8 mM NaCl and LB-Luria culture suspended in 168 mM Nacl); and 3) the change in cell mobility primarily occurred within the first 21 hours. The size of the bacterial cells was measured and the surface properties (e.g., zeta potential, hydrophobicity, cell-bound protein, LPS sugar content, outer membrane protein profiles) of the bacterial cells were characterized. We found that the measured cell surface properties could not fully explain the observed changes in cell mobility caused by starvation.

  16. Interstitial PCO2 and pH, and their role as chemostimulants in the isolated respiratory network of neonatal rats.

    PubMed Central

    Voipio, J; Ballanyi, K

    1997-01-01

    1. CO2-H(+)-sensitive microelectrodes were used for simultaneous measurements of the partial pressure of CO2 (PCO2) and extracellular pH (pHo) in the ventral respiratory group (VRG) of the isolated brainstem-spinal cord of neonatal rats. Some of the data were analysed using diffusion equations. 2. With increasing recording depth within the boundaries of the VRG (300-600 microns below the tissue surface), PCO2 increased from 77 to 95 mmHg and pHo fell from 7.0 to 6.8 at steady state in standard saline equilibrated with 5% CO2 and 95% O2. 3. Elevating bath CO2 from 5 to 10-12.5% produced a mean increase in PCO2 of 18 mmHg, a fall in pHo of 0.13 pH units, and a 50-250% increase in the frequency of respiration-related spinal (C2) nerve bursts. Similar effects on C2 activity and pHo were observed upon lowering bath [HCO3-] from 25 to 10 mM, leading to a mean decrease in PCO2 of 4.4 mmHg in the VRG. 4. Raising bath [HCO3-] to 50 mM produced a substantial frequency decrease, a rise in pHo of 0.24 pH units and an elevation in PCO2 of 9.3 mmHg. C2 activity was not profoundly affected upon doubling the CO2-HCO3- content, leading to a mean increase in pHo of 0.13 pH units and elevation of PCO2 by 30 mmHg. 5. In a CO2-HCO3(-)-free, Hepes-buffered solution, PCO2 decreased to 18 mmHg in the VRG and pHo fell by 0.15 pH units with no major effect on rhythmic activity. Subsequent anoxic exposure for more than 15 min produced a further fall in PCO2 to below 1 mmHg, a decrease in pHo of 0.55 pH units, and blockade of respiration-related activity. In three out of the six preparations tested, C2 activity could be restored by reapplication of CO2-HCO3- in the absence of O2. 6. C2 activity persisted at a reduced frequency, even up to 30 min, during anoxia in the CO2-HCO(-)-buffered saline,leading to an elevation in PCO2 of 15 mmHg and a fall in pHo of 0.18 pH units. 7. The diffusion coefficient of CO2 in the tissue was found to be equal to that in saline. Two mean estimates for anoxic tissue of the function lambda 2/ alpha of tortuosity (lambda) and extracellular volume fraction (alpha), affecting extracellular diffusion of bicarbonate, were 4.7 and 4.1. The mean rate of acid production by anoxic tissue was 1.1 mequiv 1-1 min-1. 8. The results suggest that extracellular H+ is the primary stimulating factor in central chemosensitivity, which may often mask the less evident effects of CO2. A model of diffusion of acid equivalents in brain tissue is proposed. Images Figure 2 PMID:9080379

  17. Mars - Subsurface properties from observed longitudinal variation of the 3.5-mm brightness temperature

    NASA Technical Reports Server (NTRS)

    Epstein, E. E.; Andrew, B. H.; Briggs, F. H.; Jakosky, B. M.; Palluconi, F. D.

    1983-01-01

    Extensive 3.5-mm measurements are reported which show a variation in the brightness temperature of Mars, with the Central Meridian Longitude that is generally in phase with the variation at 2.8 cm and is opposite in sign from the variations at 20 microns. It is pointed out that the phase result is not unexpected, since 3.5 mm is longer than the wavelength at which the phase behavior is expected to change. The result that the 3.5-mm rotation curve amplitude is larger than the amplitudes at both 20 microns and 2.8 cm, however, is unexpected. This result, it is noted, can be explained as a consequence of subsurface scattering from rocks smaller than 1.5 cm in radius. A correlation of subsurface scatterers with the location of the high-thermal inertial regions would be consistent with the hypothesis that rock abundance predominates in determining the thermal inertia.

  18. Ultrastructural response of rat lung to 90 days' exposure to oxygen at 450 mm Hg

    NASA Technical Reports Server (NTRS)

    Harrison, G. A.

    1974-01-01

    Young Sprague-Dawley rats were exposed to 100% oxygen at 450 mm Hg in constant environment capsules for 90 days. Lung tissue examined by electron microscopy revealed a number of changes, many similar to those observed after exposure to oxygen at 760 mm Hg for shorter periods of time. Alterations in vesicle size and number and in mitochondrial matrix and cristae appear in both the endothelial and epithelial cells. Blebbing and rarefication of cytoplasm occur in both cell layers of the alveolo-capillary wall. Also seen are fluid in the basement membrane, platelets in the capillaries, and alveolar fluid and debris. All of these alterations occur at 1 atm exposure. However, after exposure to 450 mm Hg the changes are not as widespread nor as destructive as they are at the higher pressure.

  19. GTKDynamo: a PyMOL plug-in for QC/MM hybrid potential simulations

    PubMed Central

    Bachega, José Fernando R.; Timmers, Luís Fernando S.M.; Assirati, Lucas; Bachega, Leonardo R.; Field, Martin J.; Wymore, Troy

    2014-01-01

    Hybrid quantum chemical (QC)/molecular mechanical (MM) potentials are very powerful tools for molecular simulation. They are especially useful for studying processes in condensed phase systems, such as chemical reactions, that involve a relatively localized change in electronic structure and where the surrounding environment contributes to these changes but can be represented with more computationally efficient functional forms. Despite their utility, however, these potentials are not always straightforward to apply since the extent of significant electronic structure changes occurring in the condensed phase process may not be intuitively obvious. To facilitate their use we have developed an open-source graphical plug-in, GTKDynamo, that links the PyMOL visualization program and the pDynamo QC/MM simulation library. This article describes the implementation of GTKDynamo and its capabilities and illustrates its application to QC/MM simulations. PMID:24137667

  20. Evidence for Highly Inhomogeneous mm-Wave Sources During the Impulsive Flare of May 9, 1991

    NASA Technical Reports Server (NTRS)

    Hermann, R.; Magun, A.; Kaufmann, P.; Correia, E.; Costa, J. E. R.; Machado, M. E.; Fishman, G.

    1997-01-01

    In this paper multiwavelength observations of an impulsive flare of May 9, 1991 are presented. This event was observed with the 48 GHz multibeam focal array used at the Itapetinga radio telescope, the microwave patrol telescopes at Bem and the BATSE high time resolution hard X-ray spectrometer on board CGRO. While spatially unresolved low sensitivity observations show two major impulsive peaks, the mm-wave observations with the ability of spatially high resolved tracking of the emission centroids suggest a primarily bipolar source configuration. For the first time two mm-wave sources with a spacing below the HPBW could be separated with the multibeam technique. The general features of the observations are explained as emission of partially trapped electrons. Furthermore we present evidence for highly inhomogeneous substructures within one of the two mm-wave sources for which the positional scatter of the emission center, within 2s, is less than 2".

  1. Transport IV characterisation of MgB2 conductor at a bend radius of 50mm

    NASA Astrophysics Data System (ADS)

    Young, E. A.; Falorio, I.; Beduz, C.; Bailey, W. O. S.; Yang, Y.

    2014-05-01

    Performance of state of the art MgB2 multifilamentary conductor at a required bend radius is essential for many applications including but not limited to magnets and motors. The characterisation is generally done with benchmark transport Ic but further detail can be seen in IV characteristics which are undertaken in this paper. Two conductors with the same architecture but different diameters, 0.89 and 0.45 mm were measured from 32 K to 20 K in self-field in conditions of as received and deformed to a 50 mm bend diameter, corresponding to strains of 1.4 % and 0.7 % respectively. The qualifying 0.45mm conductor was further measured in background fields up to 3 T. The smaller diameter wire was found to have no signs of degradation of critical behaviour in Ic or IV characteristics.

  2. Radio Identification of Sub-mm Sources in the Hubble Deep Field

    E-print Network

    Eric. A. Richards

    1998-11-06

    Determination of the epoch dependent star-formation rate of field galaxies is one of the principal goals of modern observational cosmology. Recently, Hughes et al. (1998) using the SCUBA instrument on the James Clerk Maxwell Telescope, report the detection of a new population of heavily dust enshrouded, star-forming galaxies at high redshifts (z > 2), dramatically altering the picture of galaxy evolution. However, we show that this interpretation must be treated with caution because of ambiguities in the identification of the host galaxies. Based on our deep, high resolution 1.4 GHz obervations of the Hubble Deep Field, we suggest alternate identifications to the sub-mm detections. These identifications argue for a substantially lower redshift to the sub-mm population with a consequential lowering of the z > 2 sub-mm/far infrared luminosity density and global star-formation rate.

  3. OpenMM 4: A Reusable, Extensible, Hardware Independent Library for High Performance Molecular Simulation

    PubMed Central

    Eastman, Peter; Friedrichs, Mark S.; Chodera, John D.; Radmer, Randall J.; Bruns, Christopher M.; Ku, Joy P.; Beauchamp, Kyle A.; Lane, Thomas J.; Wang, Lee-Ping; Shukla, Diwakar; Tye, Tony; Houston, Mike; Stich, Timo; Klein, Christoph; Shirts, Michael R.; Pande, Vijay S.

    2012-01-01

    OpenMM is a software toolkit for performing molecular simulations on a range of high performance computing architectures. It is based on a layered architecture: the lower layers function as a reusable library that can be invoked by any application, while the upper layers form a complete environment for running molecular simulations. The library API hides all hardware-specific dependencies and optimizations from the users and developers of simulation programs: they can be run without modification on any hardware on which the API has been implemented. The current implementations of OpenMM include support for graphics processing units using the OpenCL and CUDA frameworks. In addition, OpenMM was designed to be extensible, so new hardware architectures can be accommodated and new functionality (e.g., energy terms and integrators) can be easily added. PMID:23316124

  4. Department of Bioengineering Ph.D. Graduate Student Handbook

    E-print Network

    Fang-Yen, Christopher

    Bioengineering PhD students a brief history and overview of the Bioengineering department at Penn along......................................................................................................................12 TIME LIMIT FOR COMPLETION OF THE PH

  5. Improving Student Understanding of Magmatic Differentiation Using an M&M Magma Chamber

    NASA Astrophysics Data System (ADS)

    Wirth, K. R.

    2003-12-01

    Many students, especially those in introductory geology courses, have difficulty developing a deep understanding of the processes of magmatic differentiation. In particular, students often struggle to understand Bowen's reaction series and fractional crystallization. The process of fractional crystallization by gravity settling can be illustrated using a model magma chamber consisting of M&M's. In this model, each major cation (e.g., Si, Ti, Al, Fe, Mg, Ca, Na, K) is represented by a different color M&M; other kinds of differently colored or shaped pieces could also be used. Appropriate numbers of each color M&M are combined to approximate the cation proportions of a basaltic magma. Students then fractionate the magma by moving M&M's to the bottom of the magma chamber forming a series of cumulus layers; the M&M's are removed in the stoichiometric proportions of cations in the crystallizing minerals (e.g., olivine, pyroxene, feldspars, quartz, magnetite, ilmenite). Students observe the changing cation composition (proportions of colors of M&M's) in the cumulus layers and in the magma chamber and graph the results using spreadsheet software. More advanced students (e.g., petrology course) can classify the cumulates and resulting liquid after each crystallization step, and they can compare the model system with natural magmatic systems (e.g., absence of important fractionating phases, volatiles). Students who have completed this exercise generally indicate a positive experience and demonstrate increased understanding of Bowen's reaction series and fractionation processes. They also exhibit greater familiarity with mineral stoichiometry, classification, solid-solution in minerals, element behavior (e.g., incompatibility), and chemical variation diagrams. Other models (e.g., paths of equilibrium and fractional crystallization on phase diagrams) can also be used to illustrate differentiation processes in upper level courses (e.g., mineralogy and petrology).

  6. Prediction of heavy rainfall events over Rangamati, Bangladesh using high-resolution MM5 model

    NASA Astrophysics Data System (ADS)

    Ahasan, M. N.; Mannan Chowdhury, M. A.; Quadir, D. A.

    2015-04-01

    In this study, prediction of the heavy rainfall events over Rangamati, Bangladesh has been carried out using the Fifth-Generation PSU/NCAR Mesoscale Model (MM5) conducting two historical rainfall events. The model was run on two-way triple-nested domains at 45, 15, 5 km horizontal resolutions using Anthes-Kuo cumulus parameterization schemes (CPS) with MRF planetary boundary layer (PBL). Bangladesh is the main focus area in this study. Thus, Bangladesh is taken as inner most domain (D3) with 5 km horizontal resolution. The model-predicted rainfall was compared with TRMM 3B42V7 and BMD observed rainfall. Both subjective and objective evaluation methods have been followed. The MM5 model produces realistic prediction of heavy rainfall events in terms of intensity and structure. The results show that the model performed all the Day 1 (24 h), Day 2 (48 h) and Day 3 (72 h) predictions reasonably well. The predictions are more accurate for Day 2 (48 h) and worse for Day 4 (96 h) in both cases. The prediction deteriorates as the prediction time increases. Thus, the prediction may be updated in every 24 h which would provide more realistic prediction. The RMSE shows that the value for 24 h prediction lies within 10-20 mm range. The prediction error is minimal for 48 h prediction, the error ranging from 8 to 12 mm. The error increases thereafter for 72 and 96 h of predictions. The errors range from around 10-20 and 15-25 mm, respectively. The topography/terrain over the southeast hilly region of Bangladesh has not been resolved by USGS terrain data which was used in the MM5 model. Thus, accurate and high-resolution terrain data of this region is expected to improve the performance of the model over the southeast hilly regions of Bangladesh.

  7. The Galactic Centre Mini-Spiral in the MM-Regime

    NASA Technical Reports Server (NTRS)

    Kunneriath, D.; Eckart, A.; Vogel, S. N.; Teuben, P.; Muzic, I.; Schoedel, R.; Garcia-Marin, M.; Moultaka, J.; Staguhn, J.; Straubmeier, C.; Zensus, J. A.; Valencia-S., M.; Karas, V.

    2012-01-01

    Context: The mini-spiral is a feature of the interstellar medium in the central approx.2 pc of the Galactic center. It is composed of several streamers of dust and ionised and atomic gas with temperatures between a few 100 K to 10(exp 4) K. There is evidence that these streamers are related to the so-called circumnuclear disk of molecular gas and are ionized by photons from massive, hot stars in the central parsec. Aims: We attempt to constrain the emission mechanisms and physical properties of the ionized gas and dust of the mini-spiral region with the help of our multiwavelength data sets. Methods: Our observations were carried out at 1.3 mm and 3 mm with the mm interferometric array CARMA in California in March and April 2009, with the MIR instrument VISIR at ESO's VLT in June 2006, and the NIR Bry with VLT NACO in August 2009. Results: We present high resolution maps of the mini-spiral, and obtain a spectral index of 0.5 +/- 0.25 for Sgr A *, indicating an inverted synchrotron spectrum. We find electron densities within the range 0.8-1.5 x 10(exp 4)/cu cm for the mini-spiral from the radio continuum maps, along with a dust mass contribution of approx. 0.25 Mo from the MIR dust continuum. and extinctions ranging from 1.8-3 at 2.16 microns in the Bry line. Conclusions: We observe a mixture of negative and positive spectral indices in our 1.3 mm and 3 mm observations of the extended emission of the mini-spiral, which we interpret as evidence that there are a range of contributions to the thermal free-free emission by the ionized gas emission and by dust at 1.3 mm.

  8. Prediction of heavy rainfall events over Rangamati, Bangladesh using high-resolution MM5 model

    NASA Astrophysics Data System (ADS)

    Ahasan, M. N.; Mannan Chowdhury, M. A.; Quadir, D. A.

    2014-11-01

    In this study, prediction of the heavy rainfall events over Rangamati, Bangladesh has been carried out using the Fifth-Generation PSU/NCAR Mesoscale Model (MM5) conducting two historical rainfall events. The model was run on two-way triple-nested domains at 45, 15, 5 km horizontal resolutions using Anthes-Kuo cumulus parameterization schemes (CPS) with MRF planetary boundary layer (PBL). Bangladesh is the main focus area in this study. Thus, Bangladesh is taken as inner most domain (D3) with 5 km horizontal resolution. The model-predicted rainfall was compared with TRMM 3B42V7 and BMD observed rainfall. Both subjective and objective evaluation methods have been followed. The MM5 model produces realistic prediction of heavy rainfall events in terms of intensity and structure. The results show that the model performed all the Day 1 (24 h), Day 2 (48 h) and Day 3 (72 h) predictions reasonably well. The predictions are more accurate for Day 2 (48 h) and worse for Day 4 (96 h) in both cases. The prediction deteriorates as the prediction time increases. Thus, the prediction may be updated in every 24 h which would provide more realistic prediction. The RMSE shows that the value for 24 h prediction lies within 10-20 mm range. The prediction error is minimal for 48 h prediction, the error ranging from 8 to 12 mm. The error increases thereafter for 72 and 96 h of predictions. The errors range from around 10-20 and 15-25 mm, respectively. The topography/terrain over the southeast hilly region of Bangladesh has not been resolved by USGS terrain data which was used in the MM5 model. Thus, accurate and high-resolution terrain data of this region is expected to improve the performance of the model over the southeast hilly regions of Bangladesh.

  9. Ionization Measurements of SuperCDMS SNOLAB 100 mm Diameter Germanium Crystals

    SciTech Connect

    Chagani, H.; /Minnesota U.; Bauer, D.A.; /Fermilab; Brandt, D.; Brink, P.L.; /SLAC; Cabrera, B.; Cherry, M.; /Stanford U.; Silva, E.Do Couto e; Godfrey, G.G.; /SLAC; Hall, J.; Hansen, S.; /Fermilab; Hasi, J.; Kelsey, M.; Kenney, C.J.; /SLAC; Mandic, V.; /Minnesota U.; Nagasawa, D.; Novak, L.; /Stanford U.; Mirabolfathi, N.; /UC, Berkeley; Partridge, R.; /SLAC; Radpour, R.; /Minnesota U.; Resch, R.; /SLAC; Sadoulet, B.; /UC, Berkeley /Stanford U. /SLAC /Stanford U. /Santa Clara U. /Minnesota U.

    2012-06-12

    Scaling cryogenic Germanium-based dark matter detectors to probe smaller WIMP-nucleon cross-sections poses significant challenges in the forms of increased labor, cold hardware, warm electronics and heat load. The development of larger crystals alleviates these issues. The results of ionization tests with two 100 mm diameter, 33 mm thick cylindrical detector-grade Germanium crystals are presented here. Through these results the potential of using such crystals in the Super Cryogenic Dark Matter Search (SuperCDMS) SNOLAB experiment is demonstrated.

  10. Load induced stresses and plastic deformation in 450 mm silicon wafers

    NASA Astrophysics Data System (ADS)

    Fischer, A.; Kissinger, G.

    2007-09-01

    The authors present the physical basis for estimation of gravitational constraints in 450mm silicon wafers subjected to high temperature processes. They have identified and quantified the relevant phenomena to predict the mechanical behavior of very large silicon wafers horizontally stacked and ring- or pointlike supported in a vertical-type furnace. It is shown that load induced stress at the supports increases directly proportional with increasing wafer diameter, although the weight of the wafer increases with the square of diameter. The results allow the optimization for a defect-free high temperature treatment of 450mm wafer used for leading edge device fabrication in future.

  11. Ionization Measurements of SuperCDMS SNOLAB 100 mm Diameter Germanium Crystals

    NASA Astrophysics Data System (ADS)

    Chagani, H.; Bauer, D. A.; Brandt, D.; Brink, P. L.; Cabrera, B.; Cherry, M.; Do Couto e Silva, E.; Godfrey, G. G.; Hall, J.; Hansen, S.; Hasi, J.; Kelsey, M.; Kenney, C. J.; Mandic, V.; Nagasawa, D.; Novak, L.; Mirabolfathi, N.; Partridge, R.; Radpour, R.; Resch, R.; Sadoulet, B.; Seitz, D. N.; Shank, B.; Tomada, A.; Yen, J.; Young, B. A.; Zhang, J.

    2012-06-01

    Scaling cryogenic Germanium-based dark matter detectors to probe smaller WIMP-nucleon cross-sections poses significant challenges in the forms of increased labor, cold hardware, warm electronics and heat load. The development of larger crystals alleviates these issues. The results of ionization tests with two 100 mm diameter, 33 mm thick cylindrical detector-grade Germanium crystals are presented here. Through these results the potential of using such crystals in the Super Cryogenic Dark Matter Search (SuperCDMS) SNOLAB experiment is demonstrated.

  12. EFFECT OF DIET pH ON THE CONSUMPTION, BROOD REARING, AND pH OF WORKER JELLY

    E-print Network

    Paris-Sud XI, Université de

    are sensitive to changes in pH, the gut pH of the honey bee must be maintained at a fairly constant level maintain the gut and hemolymph pH at levels critical for survival because changes in pH could resultEFFECT OF DIET pH ON THE CONSUMPTION, BROOD REARING, AND pH OF WORKER JELLY PRODUCED BY CAGED HONEY

  13. Version 3.0 SOP 6a --pH October 12, 2007 pH (total hydrogen

    E-print Network

    Version 3.0 SOP 6a -- pH October 12, 2007 117 SOP 6a pH - / 1. pH (total hydrogen ion concentration pH scale) . , [H+ ] 1 kg . 2. . F T S F 4 [H ] [H ] (1 / ) [H ] [HSO ] S K+ + + - = + + (1) [H+ ]F (free concentration), ST ([HSO4 - ]+[SO4 2- ]) KS [HSO4 - ] . pH . 10 1 [H ] pH

  14. MRF with adjustable pH

    NASA Astrophysics Data System (ADS)

    Jacobs, Stephen D.

    2011-10-01

    Deterministic final polishing of high precision optics using sub-aperture processing with magnetorheological finishing (MRF) is an accepted practice throughout the world. A wide variety of materials can be successfully worked with aqueous (pH 10), magnetorheological (MR) fluids, using magnetic carbonyl iron (CI) and either ceria or nanodiamond nonmagnetic abrasives. Polycrystalline materials like zinc sulfide (ZnS) and zinc selenide (ZnSe) are difficult to polish at pH 10 with MRF, due to their grain size and the relatively low stiffness of the MR fluid lap. If microns of material are removed, the grain structure of the material begins to appear. In 2005, Kozhinova et al. (Appl. Opt. 44 4671-4677) demonstrated that lowering pH could improve MRF of ZnS. However, magnetic CI particle corrosion rendered their low pH approach unstable and unsuitable for commercial implementation. In 2009, Shafrir et al. described a sol-gel coating process for manufacturing a zirconia-coated CI particle that protects the magnetic core from aqueous corrosion (Appl. Opt .48 6797-6810). The coating process produces free nanozirconia polishing abrasives during the coating procedure, thereby creating an MR polishing powder that is "self-charged" with the polishing abrasive. By simply adding water, it was possible to polish optical glasses and ceramics with good stability at pH 8 for three weeks. The development of a corrosion resistant, MR polishing powder, opens up the possibility for polishing additional materials, wherein the pH may be adjusted to optimize effectiveness. In this paper we describe the CI coating process, the characterization of the coated powder, and procedures for making stable MR fluids with adjustable pH, giving polishing results for a variety of optical glasses and crystalline ceramics.

  15. Eukaryotic diversity at pH extremes

    PubMed Central

    Amaral-Zettler, Linda A.

    2013-01-01

    Extremely acidic (pH < 3) and extremely alkaline (pH > 9) environments support a diversity of single-cell and to a lesser extent, multicellular eukaryotic life. This study compared alpha and beta diversity in eukaryotic communities from seven diverse aquatic environments with pH values ranging from 2 to 11 using massively-parallel pyrotag sequencing targeting the V9 hypervariable region of the 18S ribosomal RNA (rRNA) gene. A total of 946 operational taxonomic units (OTUs) were recovered at a 6% cut-off level (94% similarity) across the sampled environments. Hierarchical clustering of the samples segregated the communities into acidic and alkaline groups. Similarity percentage (SIMPER) analysis followed by indicator OTU analysis (IOA) and non-metric multidimensional scaling (NMDS) were used to determine which characteristic groups of eukaryotic taxa typify acidic or alkaline extremes and the extent to which pH explains eukaryotic community structure in these environments. Spain's Rio Tinto yielded the fewest observed OTUs while Nebraska Sandhills alkaline lakes yielded the most. Distinct OTUs, including metazoan OTUs, numerically dominated pH extreme sites. Indicator OTUs included the diatom Pinnularia and unidentified opisthokonts (Fungi and Filasterea) in the extremely acidic environments, and the ciliate Frontonia across the extremely alkaline sites. Inferred from NMDS, pH explained only a modest fraction of the variation across the datasets, indicating that other factors influence the underlying community structure in these environments. The findings from this study suggest that the ability for eukaryotes to adapt to pH extremes over a broad range of values may be rare, but further study of taxa that can broadly adapt across diverse acidic and alkaline environments, respectively present good models for understanding adaptation and should be targeted for future investigations. PMID:23335919

  16. Third-body abrasive wear challenge of 32 mm conventional and 44 mm highly crosslinked polyethylene liners in a hip simulator model.

    PubMed

    Sorimachi, T; Clarke, I C; Williams, P A; Gustafson, A; Yamamoto, K

    2009-07-01

    Hip simulator studies have shown that wear in the polyethylene liners used for total hip replacements increased with the larger-diameter femoral balls and could also be exacerbated by third-body abrasion. However, they also indicated that the more highly cross-linked polyethylene (HXPE) bearings were more wear resistant than conventional polyethylene (CXPE) bearings. Unfortunately the HXPE bearings appeared to be particularly sensitive to adverse wear conditions. One simulator study in particular indicated that poly(methyl methacrylate) (PMMA) debris increased wear sixfold by means of two-body abrasive interactions rather than the supposed third-body abrasion or roughening effects of the Co-Cr surfaces. There has been no confirmation of such novel theories. Therefore the goal of this study was to investigate the sensitivity of large-diameter HXPE bearings to the third-body PMMA wear challenge in a hip simulator model. An orbital hip simulator was used in standard test mode with a physiological load profile. The 32 mm control liners were machined from moulded GUR1050 and gamma irradiated to 35 kGy under nitrogen (CXPE). The 44 mm liners were also from moulded blanks, gamma irradiated to 75 kGy, machined to shape, given a proprietary heat treatment, and sterilized by gas plasma (HXPE). As in the published simulator model, the study was conducted in three phases. In phase 1, all cups were run in standard ('clean') lubricant for 1.5 x 10(6) cycles duration. In phase 2, three CXPE cups and six HXPE cups were run for 2 x 10(6) cycles with a slurry of PMMA particles added to the lubricant. In phase 3, the implants were again run in 'clean' lubricant for 2 x 10(6) cycles duration. In addition, three HXPE cups were run as wear controls for 5.5 x 10(6) cycles duration in clean lubricant. In phase-1, the HXPE liners demonstrated twelvefold reduced wear compared with the CXPE controls. The 32 mm and 44 mm Co-Cr balls were judged of comparable roughnesses. However, the surface finish of HXPE liners was superior to that of CXPE liners. In phase-2 abrasion, wear rates increased sixfold and eighty-fold for CXPE and HXPE bearings respectively. These data confirmed that HXPE bearings were particularly sensitive to 'severe' test modes. The Co-Cr balls revealed numerous surface patches representing transferred PMMA with average transient roughness increased to 25 nm and 212 nm for the 32 mm and 44 mm balls respectively. These PMMA patches produced an aggressive two-body abrasion wear of the polyethylene. After cleaning, the ball roughness returned to near normal. Therefore the Co-Cr roughness was not an issue in this severe test mode. In phase 3, the wear decreased to near the index values of phase 1, while liner roughness dropped by more than 90 per cent. The control CXPE liners now demonstrated twice the wear of the HXPE, as would be predicted comparing the diameter and cross-linking algorithms. No previous study has correlated polyethylene roughness profiles to wear performance. In phase 2, PMMA abrasion created significant damage to the polyethylene surfaces. The average roughness Sa of CXPE liners increased to 3.6 microm, a twenty-four-fold increase with some scratches up to 40 microm deep. The HXPE roughness also increased but only to 1.5 microm, a ninefold increase. The scratch indices Sz and Sp for HXPE surfaces were also 50 per cent less severe than on CXPE surfaces. However, within 2 x 10(6) cycles duration of phase 3, all liners had recovered to virtually their original surface finish in phase 1. In all test phases, the surface finish of the HXPE liners remained superior to control liners. These experimental data confirmed many of the results from the previous simulator study with the PMMA abrasion models. Thus the 44 mm liners appeared an excellent clinical alternative to the smaller ball designs used in total hip replacements. PMID:19623913

  17. Proton and hydride transfers in solution: hybrid QMmm/MM free energy perturbation study

    SciTech Connect

    Ho, L. Lawrence [Yale Univ., New Haven, CT (United States). Gibbs Lab.]|[Argonne National Lab., IL (United States); Bash, P.A. [Argonne National Lab., IL (United States); Kerell, A.D., Jr [Maryland University, Baltimore, MD (United States). School of Pharmacy

    1996-03-01

    A hybrid quantum and molecular mechanical (QM/MM) free energy perturbation (FEP) method is implemented in the context of molecular dynamics (MD). The semiempirical quantum mechanical (QM) Hamiltonian (Austin Model 1) represents solute molecules, and the molecular mechanical (MM) CHARMM force field describes the water solvent. The QM/MM FEP method is used to calculate the free energy changes in aqueous solution for (1) a proton transfer from methanol to imidazole and (2) a hydride transfer from methoxide to nicotinamide. The QM/MM interaction energies between the solute and solvent arc calibrated to emulate the solute-solvent interaction energies determined at the Hartee-Fock 6-31G(d) level of ab initio theory. The free energy changes for the proton and hydride transfers are calculated to be 15.1 and {minus}6.3 kcal/mol, respectively, which compare favorably with the corresponding experimental values of 12.9 and {minus}7.4 kcal/mol. An estimate of the reliability of the calculations is obtained through the computation of the forward (15.1 and {minus}6.3 kcal/mol) and backward ({minus}14.1 and 9.1 kcal/mol)free energy changes. The reasonable correspondence between these two independent calculations suggests that adequate phase space sampling is obtained along the reaction pathways chosen to transform the proton and hydride systems between their respective reactant and product states.

  18. Example1Faculty MembersMedical Science As of , 2 , 7 (yyyy,mm dd)

    E-print Network

    Miyashita, Yasushi

    retirement date) 1995 4 3 Intern Doctor yyyy mm 6 Regular Employee Doctor-in-training (Intern) Regular Employee Address (excl. block numbers) Trained at the Emergency Department. Engaged in research, ***** University Hospital ***** City, ***** Prefecture Trained in Internal Medicine. Engaged in research

  19. Optimal Measurement-based Pricing for an M/M/1 Queue

    E-print Network

    Tuffin, Bruno

    networks, where pricing can be used to control congestion, and the network can be characterized by a single a suitable pricing scheme, the facility manager can control congestion, of- fer satisfactory qualityOptimal Measurement-based Pricing for an M/M/1 Queue Yezekael Hayel1 and Bruno Tuffin1 IRISA

  20. Films--Too Good for Words. A Directory of Nonnarrated 16mm Films.

    ERIC Educational Resources Information Center

    Parlato, Salvatore J., Jr.

    A nonnarrated film is one that communicates pictorially on the strength of its visual unity, continuity, and coherence without relying on narration or dialogue. This directory lists 1,000 such 16mm films, mostly curriculum-oriented educational films, in three main parts. The first part describes films under subject headings such as the arts, other…

  1. Atmospheric Dielectric-Barrier Discharges Scalable From 1 mm to 1 m

    Microsoft Academic Search

    James L. Walsh; Zhi Cao; Michael G. Kong

    2008-01-01

    Three types of atmospheric dielectric-barrier discharges are presented to illustrate their potential for uniform surface treatment with a length scale spanning from 1 mm to 1 m. As these atmospheric discharges are scaled up in size, it is increasingly difficult to sustain their plasma stability. By using nanosecond images, it is shown that the use of high excitation frequencies is

  2. Program Guidelines M.M. Collaborative Piano School of Music Page 1 University of Utah

    E-print Network

    Program Guidelines M.M. Collaborative Piano School of Music Page 1 University of Utah Revised 5/26/10 Master of Music: Collaborative Piano Required Courses ­ All courses MUSC Academic Courses (11 hours Instructor) 9 6366 Advanced Teaching Seminar I 2 6367 Advanced Teaching Seminar II 2 6380 Advanced Piano

  3. Program Guidelines M.M. Piano Performance School of Music Page 1 University of Utah

    E-print Network

    Program Guidelines M.M. Piano Performance School of Music Page 1 University of Utah Revised 8/30/10 Master of Music: Piano Performance Required Courses (All courses MUSC) Semester Credit Hrs 6010 Music) 6 6366, 6367 Advanced Teaching Seminar 4 (2+2) 6380, 6381 Advanced Piano Literature I, II 6 (3

  4. THE ENIGMATIC CORE L1451-mm: A FIRST HYDROSTATIC CORE? OR A HIDDEN VeLLO?

    SciTech Connect

    Pineda, Jaime E.; Goodman, Alyssa A.; Bourke, Tyler; Foster, Jonathan B.; Robitaille, Thomas; Kauffmann, Jens [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Arce, Hector G.; Tanner, Joel [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Schnee, Scott [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903 (United States); Tafalla, Mario [Observatorio Astronomico Nacional (IGN), Alfonso XII 3, E-28014 Madrid (Spain); Caselli, Paola [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Anglada, Guillem, E-mail: jaime.pineda@manchester.ac.uk [Instituto de Astrofisica de Andalucia, CSIC, Apartado 3004, E-18080 Granada (Spain)

    2011-12-20

    We present the detection of a dust continuum source at 3 mm (CARMA) and 1.3 mm (Submillimeter Array, SMA), and {sup 12}CO (2-1) emission (SMA) toward the L1451-mm dense core. These detections suggest a compact object and an outflow where no point source at mid-infrared wavelengths is detected using Spitzer. An upper limit for the dense core bolometric luminosity of 0.05 L{sub Sun} is obtained. By modeling the broadband spectral energy distribution and the continuum interferometric visibilities simultaneously, we confirm that a central source of heating is needed to explain the observations. This modeling also shows that the data can be well fitted by a dense core with a young stellar object (YSO) and a disk, or by a dense core with a central first hydrostatic core (FHSC). Unfortunately, we are not able to decide between these two models, which produce similar fits. We also detect {sup 12}CO (2-1) emission with redshifted and blueshifted emission suggesting the presence of a slow and poorly collimated outflow, in opposition to what is usually found toward YSOs but in agreement with prediction from simulations of an FHSC. This presents the best candidate, so far, for an FHSC, an object that has been identified in simulations of collapsing dense cores. Whatever the true nature of the central object in L1451-mm, this core presents an excellent laboratory to study the earliest phases of low-mass star formation.

  5. Daily dosimetric quality control of the MM50 Racetrack Microtron using an electronic portal imaging device

    Microsoft Academic Search

    M. L. P. Dirkx; M. Kroonwijk; J. C. J. de Boer; B. J. M. Heijmen

    1995-01-01

    The MM50 Racetrack Microtron, suited for advanced three-dimensional conformal radiotherapy techniques, is a complex machine in various respects. Therefore, for a number of gantry angles, daily quality control of the absolute output and fluence profiles of the scanned beams are mandatory. For the applied photon beams, a fast method for these daily checks, based on dosimetric measurements with the Philips

  6. Polystyrene PS648 inlet optical birefringence pattern, piston speed 1.4mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 1.4 mm/s at 170C. Video shows the inlet flow (from bottom to top)....

  7. Polystyrene PS648 outlet optical birefringence pattern, piston speed 1.4mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 1.4 mm/s at 170C. Video shows the outlet flow (from top to bottom)....

  8. Polystyrene PS648 inlet optical birefringence pattern, piston speed 1.0mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 1.0 mm/s at 170C. Video shows the inlet flow (from bottom to top)....

  9. Polystyrene PS648 outlet optical birefringence pattern, piston speed 1.0mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 1.0 mm/s at 170C. Video shows the outlet flow (from top to bottom)....

  10. Polystyrene PS648 inlet optical birefringence pattern, piston speed 0.16mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 0.16 mm/s at 170C. Video shows the inlet flow (from bottom to top)....

  11. Polystyrene PS648 outlet optical birefringence pattern, piston speed 0.16mm/s

    E-print Network

    Hassell, David

    2008-08-27

    The optical birefringence pattern obtained from polystyrene PS648 flowing through a narrow slit. Experiment conducted on the Cambridge Multi Pass Rheometer (MPR4) at a piston speed of 0.16 mm/s at 170C. Video shows the outlet flow (from top...

  12. Evaluation of 40 x 22 mm coverslip area in cervical cancer screening.

    PubMed

    Oommen, R; Curling, M; Adams, C; Barrett, E; Titmuss, E; Widdowson, A

    1998-02-01

    Nine hundred and twenty-three smears covered by 40 x 22 mm size coverslips were examined inside and outside the coverslip area to determine whether this coverslip size could be responsible for missed dyskaryotic cells in conventional cervical cancer screening. There was no instance when abnormal cells seen outside the coverslip were not also present within the coverslipped area. PMID:9523128

  13. Length: 4-15 mm Larvae (maggots): Creamy-white to green or

    E-print Network

    Hover fly Syrphidae Length: 4-15 mm Larvae (maggots): Creamy-white to green or brown. Worm- ally has black and yellow stripes. Adults often hover over flow- ers (hence the com- mon name "hover and pollen. Hover fly ­ continued #12;

  14. [Multiple wounds caused by a 5.56 mm bullet: the Famas, a competitive weapon].

    PubMed

    Jancovici, R; Jourdan, P; Mianne, D; Naudan, P; Brissiaud, J C; Pailler, J L

    1987-10-01

    A case is reported of multiple wounds to abdomen and spine from a 5.56 mm bullet. Differing from currently used weapons, a high speed bullet is projected producing damage that has been studied precisely and compared with lesions caused by conventional bullets. The weapon responsible is progressively equipping a certain number of French regiments. PMID:3693439

  15. Press Advertising 39x3col (390mm x 3 cols)

    E-print Network

    Botea, Adi

    Press Advertising 39x3col (390mm x 3 cols) Total cost of ad Canberra Times $1,682.49 HES $4. 200 words Canberra Times $1,037.29 HES $2,785.00 STANDALONE Press advertising describes job advertisements in a printed medium such as newspapers, magazines and journals. We currently primarily advertised

  16. Leonardo's vision of flow visualization M. Gharib, D. Kremers, M.M. Koochesfahani, M. Kemp

    E-print Network

    Koochesfahani, Manoochehr M.

    Leonardo's vision of flow visualization M. Gharib, D. Kremers, M.M. Koochesfahani, M. Kemp Abstract an immense, tiresome and confused amount of writing and time''. (Kemp 1972) And he goes on to say that ``a knowledge of them'' (Kemp 1989). He followed this approach while always trying to avoid ``Sciences (read

  17. 16mm Film and Videotape Lectures and Demonstrations. 1976/1977 Catalog.

    ERIC Educational Resources Information Center

    Massachusetts Inst. of Tech., Cambridge. Center for Advanced Engineering Study.

    The Massachusetts Institute of Technology provides a catalog of 16mm filmed and videotaped lectures and demonstrations. Each listing includes title, short description, length of presentation, catalog number, purchase and rental prices, and indications as to whether the item is film or videotape and black-and-white or color. The catalog is divided…

  18. CVB: The Constrained Vapor Bubble 40 mm Capillary Experiment on the ISS

    NASA Technical Reports Server (NTRS)

    Wayner, Peter C., Jr.; Kundan, Akshay; Plawsky, Joel

    2013-01-01

    Discuss the Constrained Vapor Bubble (CVB) 40mm Fin experiment on the ISS and how it aims to achieve a better understanding of the physics of evaporation and condensation and how they affect cooling processes in microgravity using a remotely controlled microscope and a small cooling device

  19. Histological study of a polyamide arterial allograft (inside diameter: 1.5 mm) in rats.

    PubMed

    Robert, H; Honiger, J; Leconte; Apoil, A

    1986-01-01

    The histological results of the implantation of twenty aortal prosthesis (6-6 polyamide, internal diameter 1.5 mm) in rats are presented. The success rate is 77%. Biological tolerance is remarkably good. After the first month, the formation of a continuous endothelial layer is noted. At three months, the structure of the neo-membrane resembles that of the aortal. PMID:3741159

  20. Improving Student Understanding of Magmatic Differentiation Using an M&M Magma Chamber

    Microsoft Academic Search

    K. R. Wirth

    2003-01-01

    Many students, especially those in introductory geology courses, have difficulty developing a deep understanding of the processes of magmatic differentiation. In particular, students often struggle to understand Bowen's reaction series and fractional crystallization. The process of fractional crystallization by gravity settling can be illustrated using a model magma chamber consisting of M&M's. In this model, each major cation (e.g., Si,

  1. A 15 15 mm, 1 A, Reliable Sensor-Net Module: Enabling Application-Specific Nodes

    E-print Network

    Savvides, Andreas

    -power sensor-net module. ZN1 integrates MCU, RF, and RTC into an ultra-small 15 Ã? 15-mm module with an ultra diagram. CC2420 RF, H8S/2218 MCU, temperature sensor, extension connector, and RTC are integrated into 15 the MCU are output through extension connector for providing flexible connectivity for sensors and other

  2. Explosion Welding High Temperature and Wear Resistant Metal Liners into 25 mm Gun Barrels

    Microsoft Academic Search

    Donald J. Butler; David G. Brasher

    2012-01-01

    This paper describes the explosion welding process and how it has been adapted for welding high temperature and wear resistant metal liners into 25 mm gun barrels. Explosion welding is a process that is used to join two dissimilar metals together. Explosives are used to drive two plates together at a very high velocity. The energetic collision cleans both surfaces and

  3. RECHERCHES PHOTOGRAPHIQUES SUR LES RAYONS DE RNTGEN (1); Par MM. AUGUSTE et LOUIS LUMIRE.

    E-print Network

    Paris-Sud XI, Université de

    171 RECHERCHES PHOTOGRAPHIQUES SUR LES RAYONS DE RÖNTGEN (1); Par MM. AUGUSTE et LOUIS LUMIÈRE. Nous nous sommes attachés à l'étude de l'action des rayons X sur les substances sensibles, nous avons remarqué d'abord que les rayons de Rôntgen agissent de la même manière sur des plaques au géla- tino

  4. Barium ferrite particulate tapes for high-band 8 mm VCR

    Microsoft Academic Search

    H. Yokoyama; T. Ito; M. Isshiki; K. Kurata; T. Fukaya

    1992-01-01

    Barium ferrite particulate media have been applied to recording tapes for a high-band 8 mm VCR, with full compatibility with metal particulate tapes, although they have remarkably different magnetic and recording characteristics. The compatibility of barium ferrite tapes to metal particulate tapes has been attained by adopting barium ferrite particles with an average diameter of 50 nm and a diameter

  5. Quench performance of 50-mm aperture, 15-m-long SSC dipole magnets built at Fermilab

    SciTech Connect

    Kuzminski, J.; Bush, T.; Coombes, R. [and others

    1992-07-01

    The quench performance, ramp rate dependence, and mechanical behavior of ten full-length, 50-mm-aperture, SSC dipole magnets built at Fermilab are discussed. Cold testing of these magnets shows that the quench plateau established at 4.35 K exceeds the design value by more than 10%, virtually without training.

  6. Recent trends in Antarctic snow accumulation from Polar MM5 simulations

    E-print Network

    Howat, Ian M.

    Recent trends in Antarctic snow accumulation from Polar MM5 simulations BY ANDREW J. MONAGHAN 1, is employed to simulate Antarctic accumulation in recent decades. Two sets of simulations, each with different different from zero, suggesting that recent Antarctic snowfall changes do not mitigate current sea

  7. PART 1. Student background University ID Social Security number Birthdate (mm/dd/yyyy)

    E-print Network

    Amin, S. Massoud

    PART 1. Student background University ID Social Security number Birthdate (mm/dd/yyyy) Current Middle name Suffix Your new name (as it appears on the attached photocopy of your Social Security card *MUST* submit a photocopy of your Social Security card along with this form. All others may submit

  8. Fabrication of mm-wave undulator cavities using deep x-ray lithography

    SciTech Connect

    Song, J.J.; Kang, Y.W.; Kustom, R.L.; Lai, B.; Nassiri, A. [Argonne National Lab., IL (United States); Feinerman, A.D. [Illinois Univ., Chicago, IL (United States); White, V.; Well, G.M. [Wisconsin Univ., Madison, WI (United States). Center for X-Ray Lithography

    1995-12-31

    The possibility of fabricating mm-wave radio frequency cavities (100-300 GHz) using deep x-ray lithography (DXRL) is being investigated. The fabrication process includes manufacture of precision x-ray masks, exposure of positive resist by x-ray through the mask, resist development, and electroforming of the final microstructure. Highly precise, two-dimensional features can be machined onto wafers using DXRL. Major challenges are: fabrication of the wafers into three-dimensional rf structures; alignment and overlay accuracy of structures; adhesion of the PMMA on the copper substrate; and selection of a developer to obtain high resolution. Rectangular cavity geometry is best suited to this fabrication technique. A 30- or 84-cell 108-GHz mm-wave structure can serve as an electromagnetic undulator. A mm-wave undulator, which will be discussed later, may have special features compared to the conventional undulator. First harmonic undulator radiation at 5.2 KeV would be possible using the Advanced Photon Source (APS) linac system, which provides a low-emittance electron beam by using an rf thermionic gun with an energy as high as 750-MeV. More detailed rf simulation, heat extraction analysis, beam dynamics using a mm-wave structure, and measurements on lOx larger scale models can be found in these proceedings.

  9. Interferometric detections of GOODS 850-5 at 1 mm and 1.4 GHz

    E-print Network

    H. Dannerbauer; F. Walter; G. Morrison

    2007-12-19

    We have obtained a position (at sub-arcsecond accuracy) of the submillimeter bright source GOODS 850-5 (also known as GN10) in the GOODS North field using the IRAM Plateau de Bure interferometer at 1.25 mm wavelengths (MM J123633+6214.1, flux density: S(1.25 mm)=5.0+-1.0 mJy). This source has no optical counterpart in deep ACS imaging down to a limiting magnitude of i(775)=28.4 mag and its position is coincident with the position found in recent sub-millimeter mapping obtained at the SMA (Wang et al. 2007). Using deep VLA imaging at 20 cm, we find a radio source (S(20 cm)=32.7+-4.3 microJy) at the same position that is significantly brighter than reported in Wang et al. The source is detected by Spitzer in IRAC as well as at 24 microns. We apply different photometric redshift estimators using measurements of the dusty, mid/far-infrared part of the SED and derive a redshift z~4. Given our detection in the millimeter and radio we consider a significantly higher redshift (e.g., z~6 Wang et al. 2007) unlikely. MM J123633+6214.1 alias GOODS 850-5 nevertheless constitutes a bright representative of the high-redshift tail of the submillimeter galaxy population that may contribute a significant fraction to the (sub)millimeter background.

  10. Effective Focal Shift at Target (mm) -3 -2 -1 0 1 2 3

    E-print Network

    effective focal shifts indicate regimes of guiding and not-guiding. The guiding regime suggests mismatchedEntries 49 Mean 0.08 RMS 0.5 Effective Focal Shift at Target (mm) -3 -2 -1 0 1 2 3 Entries 0 2 4 6 of a laser pulse without waveguide. (Right) Retrieved phase map 3. Calculate radius of curvature, Rc, from

  11. QM/MM simulations as an assay for carbapenemase activity in class A ?-lactamases.

    PubMed

    Chudyk, Ewa I; Limb, Michael A L; Jones, Charlotte; Spencer, James; van der Kamp, Marc W; Mulholland, Adrian J

    2014-12-01

    Carbapenems, 'last resort' antibiotics for many bacterial infections, can now be broken down by several class A ?-lactamases (i.e. carbapenemases). Here, carbapenemase activity is predicted through QM/MM dynamics simulations of acyl-enzyme deacylation, requiring only the 3D structure of the apo-enzyme. This may assist in anticipating resistance and future antibiotic design. PMID:25321894

  12. The three-dimensional structure of Saturn's E ring M.M. Hedman a,

    E-print Network

    Hamilton, Douglas P.

    The three-dimensional structure of Saturn's E ring M.M. Hedman a, , J.A. Burns a,b , D.P. Hamilton Accepted 2 November 2011 Available online 19 November 2011 Keywords: Planetary rings Saturn, Rings Disks a b s t r a c t Saturn's diffuse E ring consists of many tiny (micron and sub-micron) grains of water

  13. Development of optical ground verification method for mum to sub-mm reflectors

    Microsoft Academic Search

    Y. Stockman; C. Thizy; P. Lemaire; M. Georges; E. Mazy; A. Mazzoli; Y. Houbrechts; P. Rochus; S. Roose; D. Doyle; G. Ulbrich

    2004-01-01

    Large reflectors and antennas for the IR to mm wavelength range are being planned for many Earth observation and astronomical space missions and for commercial communication satellites as well. Scientific observatories require large telescopes with precisely shaped reflectors for collecting the electro-magnetic radiation from faint sources. The challenging tasks of on-ground testing are to achieve the required accuracy in the

  14. QM/MM Calculations in Drug Discovery: A Useful Method for Studying Binding M. Paul Gleeson*,

    E-print Network

    Nielsen, Steven O.

    for conformational sampling. 1. INTRODUCTION Structure-based drug design (SBDD) is an important component of the drugQM/MM Calculations in Drug Discovery: A Useful Method for Studying Binding Phenomena? M. Paul subtle binding phenomena found within pharmaceutical drug discovery programs. The goal

  15. Improved surface quality of anisotropically etched silicon {111} planes for mm-scale integrated optics

    E-print Network

    Cotter, J P; Kraft, M; Hinds, E A

    2013-01-01

    We have studied the surface quality of millimeter-scale optical mirrors produced by etching CZ and FZ silicon wafers in potassium hydroxide to expose the $\\{111\\}$ planes. We find that the FZ surfaces have four times lower noise power at spatial frequencies up to $500\\, {mm}^{-1}$. We conclude that mirrors made using FZ wafers have higher optical quality.

  16. Improved surface quality of anisotropically etched silicon {111} planes for mm-scale optics

    NASA Astrophysics Data System (ADS)

    Cotter, J. P.; Zeimpekis, I.; Kraft, M.; Hinds, E. A.

    2013-11-01

    We have studied the surface quality of millimetre-scale optical mirrors produced by etching CZ and FZ silicon wafers in potassium hydroxide to expose the {111} planes. We find that the FZ surfaces have four times lower noise power at spatial frequencies up to 500?mm-1. We conclude that mirrors made using FZ wafers have higher optical quality.

  17. MAPPING GREEN MACROALGAE BLOOMS IN A PACIFIC NORTHWEST ESTUARY VIA 35-MM AERIAL PHOTOS

    EPA Science Inventory

    Summer blooms of green macroalgae (mainly Ulva spp. and Enteromorpha spp.) on intertidal mudflats of Oregon's Yaquina Bay estuary were documented using oblique 35-mm color-infrared aerial photographs taken at low tide. Costs were controlled by use of a small airplane from a loc...

  18. A 146 mm2 8 Gb NAND flash memory with 70 nm CMOS technology

    Microsoft Academic Search

    Takahiko Hara; Koichi Fukuda; Kazuhisa Kanazawa; N. Shibata; K. Hosono; H. Maejima; M. Nakagawa; T. Abe; M. Kojima; M. Fujiu; Y. Takeuchi; K. Amemiya; M. Morooka; T. Kamei; H. Nasu; K. Kawano; Chi-Ming Wan; K. Sakurai; N. Tokiwa; H. Waki; T. Maruyama; S. Yoshikawa; M. Higashitani; T. D. Pham; T. Watanabe

    2005-01-01

    A 146 mm2 8 Gb NANO flash memory with 4-level programmed cells is fabricated in a 70 nm CMOS technology. A single-sided pad architecture and extended block-addressing scheme without redundancy is adopted for die size reduction. The programming throughput is 6 MB\\/s and is comparable to binary flash memories.

  19. Thermal Characteristics of a Hepatic Cryolesion Formed in Vitroby a 3-mm Implantable Cryoprobe

    Microsoft Academic Search

    C. M. Lam; S. M. Shimi; A. Cuschieri

    1998-01-01

    The objective of the investigation was to characterize the hepatic cryolesion formed with an implantable needle (3 × 100 mm) cryoprobe. This was used to produce cryolesions in isolated porcine liver tissue equilibrated to 37°C in a water bath. The shape, size, and temperature zones within the cryolesion and the effect of single versus repeated freeze–thaw cycles on cryolesion size

  20. 10. Southeast end; view to northwest, 65mm lens. Note evidence ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Southeast end; view to northwest, 65mm lens. Note evidence of extreme building failure caused by adjacent railroad cut, which necessitated building demolition. (Vignetting due to extreme use of camera swing necessitated by lack of space to position camera otherwise.) - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  1. 32. VERTICAL OSCILLATIONS, 3/4 VIEW, 7 NOVEMBER 1940, FROM 16MM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. VERTICAL OSCILLATIONS, 3/4 VIEW, 7 NOVEMBER 1940, FROM 16MM FILM SHOT PROFESSOR F.B. FARQUHARSON, UNIVERSITY OF WASHINGTON. (LABORATORY STUDIES ON THE TACOMA NARROWS BRIDGE, AT UNIVERSITY OF WASHINGTON (SEATTLE: UNIVERSITY OF WASHINGTON, DEPARTMENT OF CIVIL ENGINEERING, 1941) - Tacoma Narrows Bridge, Spanning Narrows at State Route 16, Tacoma, Pierce County, WA

  2. 1. East portal of Tunnel 3, view to west, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. East portal of Tunnel 3, view to west, 135mm lens. This tunnel was photographed to provide context, because even though somewhat enlarged, it illustrates the nature of the unlined hard rock tunnels typical of the original Central Pacific construction in 1868. - Central Pacific Transcontinental Railroad, Tunnel No. 3, Milepost 180.65, Cisco, Placer County, CA

  3. Release of dopamine and chemoreceptor discharge induced by low pH and high PCO2 stimulation of the cat carotid body.

    PubMed Central

    Rigual, R; López-López, J R; Gonzalez, C

    1991-01-01

    1. Cat carotid bodies were incubated with the precursor [3H]tyrosine to label the catecholamine deposits and then mounted in a superfusion chamber which allowed simultaneous collection of the released [3H]dopamine (DA) and recording of action potentials from the carotid sinus nerve. 2. Low pH (7.2-6.6) superfusion of the carotid bodies for periods of 10 min produced a parallel increase in the release of [3H]DA and chemoreceptor discharge. 3. Carotid sinus nerve denervation of the carotid body 12-15 days prior to the experiments did not modify the release of [3H]DA elicited by low pH. 4. Superfusion of the carotid bodies with Ca(2+)-free, high-Mg2+ (1.6 mM) media reduced basal release of [3H]DA and chemoreceptor discharge by about 30%. Release evoked by low pH was reduced by 82%. Peak and average chemoreceptor discharge recorded in response to low pH were reduced by 28%. 5. Solutions containing weak acids (sodium acetate, 10 mM), adjusted at pH 7.4, elicited release of [3H]DA and increased chemoreceptor discharge. 6. With HCO3-CO2-buffered superfusion media, a reduction of bicarbonate to 5.6 mM (pH 6.8), an increase in CO2 to 20% (pH 6.8), or a simultaneous increase in CO2 to 20% and bicarbonate to 90 mM (pH 7.4), resulted in all cases in a corresponding increase in [3H]DA release and chemoreceptor discharge. The most effective stimulus was 20% CO2-pH 6.8 and the least effective 5% CO2-5.6 mM-HCO3-pH 6.8. 7. Inhibition of carbonic anhydrase with acetazolamide while perfusing the carotid bodies with a 20% CO2-equilibrated (pH 7.4) solution resulted in comparable reductions in the release of [3H]DA and chemoreceptor discharge. 8. It is concluded that the effective acidic stimulus at the carotid body chemoreceptors is an increase in hydrogen ion concentration in type I cells. It is also concluded that DA plays a critical role in the genesis of carotid sinus nerve discharges. PMID:1841956

  4. The Effect of Crystallizing and Non-crystallizing Cosolutes on Succinate Buffer Crystallization and the Consequent pH Shift in Frozen Solutions

    SciTech Connect

    Sundaramurthi, Prakash; Suryanarayanan, Raj (UMM)

    2011-09-06

    To effectively inhibit succinate buffer crystallization and the consequent pH changes in frozen solutions. Using differential scanning calorimetry (DSC) and X-ray diffractometry (XRD), the crystallization behavior of succinate buffer in the presence of either (i) a crystallizing (glycine, mannitol, trehalose) or (ii) a non-crystallizing cosolute (sucrose) was evaluated. Aqueous succinate buffer solutions, 50 or 200 mM, at pH values 4.0 or 6.0 were cooled from room temperature to -25 C at 0.5 C/min. The pH of the solution was measured as a function of temperature using a probe designed to function at low temperatures. The final lyophiles prepared from these solutions were characterized using synchrotron radiation. When the succinic acid solution buffered to pH 4.0, in the absence of a cosolute, was cooled, there was a pronounced shift in the freeze-concentrate pH. Glycine and mannitol, which have a tendency to crystallize in frozen solutions, remained amorphous when the initial pH was 6.0. Under this condition, they also inhibited buffer crystallization and prevented pH change. At pH 4.0 (50 mM initial concentration), glycine and mannitol crystallized and did not prevent pH change in frozen solutions. While sucrose, a non-crystallizing cosolute, did not completely prevent buffer crystallization, the extent of crystallization was reduced. Sucrose decomposition, based on XRD peaks attributable to {beta}-D-glucose, was observed in frozen buffer solutions with an initial pH of 4.0. Trehalose completely inhibited crystallization of the buffer components when the initial pH was 6.0 but not at pH 4.0. At the lower pH, the crystallization of both trehalose dihydrate and buffer components was evident. When retained amorphous, sucrose and trehalose effectively inhibited succinate buffer component crystallization and the consequent pH shift. However, when trehalose crystallized or sucrose degraded to yield a crystalline decomposition product, crystallization of buffer was observed. Similarly, glycine and mannitol, two widely used bulking agents, inhibited buffer component crystallization only when retained amorphous. In addition to stabilizing the active pharmaceutical ingredient, lyoprotectants may prevent solution pH shift by inhibiting buffer crystallization.

  5. Somatic embryogenesis of carrot in hormone-free medium: external pH control over morphogenesis

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1990-01-01

    Cultures of preglobular stage proembryos (PGSPs) were initiated from mechanically wounded mature zygotic embryos of carrot, Daucus carota, on a hormone-free, semisolid medium. These PGSPs have been maintained and multiplied for extended periods without their progression into later embryo stages on the same hormone-free medium containing 1 mM NH4+ as the sole nitrogen source. Sustained maintenance of cultures comprised exclusively of PGSPs was dependent on medium pH throughout the culture period. Best growth and multiplication of PGSP cultures occurred when the pH of unbuffered, hormone-free medium fell from 4.5 to 4 over a 2-week period or when buffered medium was titrated to pH 4. If the hormone-free medium was buffered to sustain a pH at or above 4.5, PGSPs developed into later embryo stages. Maintenance with continuous multiplication of PGSPs occurred equally well on medium containing NH4+ or NH4+ and NO3-, but growth was poor with NO3- alone. Additional observations on the effects of medium components such as various nitrogen sources and levels, sucrose concentration, semisolid supports, type of buffer, borate concentration, activated charcoal, and initial pH that permit optimum maintenance of the PGSPs or foster their continued developmental progression into mature embryos and plantlets are reported. The influence of the pH of the hormone-free medium as a determinant in maintaining cultures as PGSPs or allowing their continued embryonic development are unequivocally demonstrated by gross morphology, scanning electron microscopy, and histological preparations.

  6. Exchangeable hydrogen explains the pH of spodosol Oa horizons

    USGS Publications Warehouse

    Ross, D.S.; David, M.B.; Lawrence, G.B.; Bartlett, R.J.

    1996-01-01

    The chemistry of extremely acid Oa horizons does not conform to traditional pH, Al, and base saturation relationships. Results from two separate studies of northeastern U.S. forested soils were used to investigate relationships between pH in water or dilute salt solutions and other soil characteristics. In Oa horizons with pH below 4, soil pH in dilute CaCl2 solution was correlated with exchangeable H+ measured either by titration (r = -0.88, P = 0.0001, n = 142) or by electrode (r = -0.89, P = 0.0001, n = 45). Exchangeable H+ expressed as a percentage of the cation-exchange capacity (CEC) was linear with pH and showed similar slopes for data from both studies. For all samples, pHw = 4.21 - 1.80 x H+/CEC (R2 = 0.69, n = 194). The reciprocal of the H+/CEC ratio is base saturation with Al added to the bases. Because of the low pH, exchangeable Al does not appear to behave as an acid. Exchangeable H+ remains an operationally defined quantity because of the difficulty in separating exchange and hydrolysis reactions. In a variety of neutral-salt extractants, concentration of H+ were correlated with 0.1 M BaCl2-exchangeable H+ (r > 0.91, P = 0.0001, n = 26) regardless of the strength of the extract. Nine successive extractions with 0.33 mM CaCl2 removed more H+ than was removed by single batch extractions with either 1 M KCl or 0.1 M BaCl2 (average H+ of 70, 43, and 49 mmol kg-1, respectively for 26 samples). The data showed little difference in the chemical behavior of Oa horizons from a variety of geographical sites and vegetation types.

  7. Advances in QM/MM Simulations for Organic and Enzymatic Reactions

    PubMed Central

    2010-01-01

    CONSPECTUS Application of combined quantum and molecular mechanical (QM/MM) methods focuses on predicting activation barriers and the structures of stationary points for organic and enzymatic reactions. Characterization of the factors that stabilize transition structures in solution and in enzyme active sites provides a basis for design and optimization of catalysts. Continued technological advances allowed expansion from prototypical cases to mechanistic studies featuring detailed enzyme and condensed-phase environments with full integration of the QM calculations and configurational sampling. This required improved algorithms featuring fast QM methods, advances in computing changes in free energies including free-energy perturbation (FEP) calculations, and enhanced configurational sampling. In particular, the present Account highlights development of the PDDG/PM3 semiempirical QM method, computation of multidimensional potentials of mean force (PMF), incorporation of on-the-fly QM in Monte Carlo (MC) simulations, and a polynomial quadrature method for efficient modeling of proton-transfer reactions. The utility of this QM/MM/MC/FEP methodology is illustrated for a variety of organic reactions including substitution, decarboxylation, elimination, and pericyclic reactions. Comparison with experimental kinetic results on medium effects has verified the accuracy of the QM/MM approach in the full range of solvents from hydrocarbons to water to ionic liquids. Corresponding results from ab initio and density functional theory (DFT) methods with continuum-based treatments of solvation reveal deficiencies, particularly for protic solvents. Also summarized in this Account are three specific QM/MM applications to biomolecular systems: (1) a recent study that clarified the mechanism for the reaction of 2-pyrone derivatives catalyzed by macrophomate synthase as a tandem Michael-aldol sequence rather than a Diels-Alder reaction; (2) elucidation of the mechanism of action of fatty acid amide hydrolase (FAAH), an unusual Ser-Ser-Lys proteolytic enzyme; and, (3) the construction of enzymes for Kemp elimination of 5-nitrobenzisoxazole that highlights the utility of QM/MM in the design of artificial enzymes. PMID:19728702

  8. Differential genotoxicity of diphenyl diselenide (PhSe)2 and diphenyl ditelluride (PhTe)2

    PubMed Central

    Meinerz, Daiane Francine; Allebrandt, Josiane; Mariano, Douglas O.C.; Waczuk, Emily P.; Soares, Felix Antunes

    2014-01-01

    Organoselenium compounds have been pointed out as therapeutic agents. In contrast, the potential therapeutic aspects of tellurides have not yet been demonstrated. The present study evaluated the comparative toxicological effects of diphenyl diselenide (PhSe)2 and diphenyl ditelluride (PhTe)2 in mice after in vivo administration. Genotoxicity (as determined by comet assay) and mutagenicicity were used as end-points of toxicity. Subcutaneous administration of high doses of (PhSe)2 or (PhTe)2 (500 µmol/kg) caused distinct genotoxicity in mice. (PhSe)2 significantly decreased the DNA damage index after 48 and 96 h of its injection (p < 0.05). In contrast, (PhTe) caused a significant increase in DNA damage (p < 0.05) after 48 and 96 h of intoxication. (PhSe)2 did not cause mutagenicity but (PhTe)2 increased the micronuclei frequency, indicating its mutagenic potential. The present study demonstrated that acute in vivo exposure to ditelluride caused genotoxicity in mice, which may be associated with pro-oxidant effects of diphenyl ditelluride. In addition, the use of this compound and possibly other related tellurides must be carefully controlled. PMID:24711962

  9. PhD in Management The PhD program in Management is

    E-print Network

    Stuart, Steven J.

    and IS or with high-quality faculty in entrepreneurship and strategic management as well as organizational behaviorPhD in Management The PhD program in Management is designed to provide advanced education currently features two distinct, focused tracks: (1) Supply Chain and Operations Management, and (2

  10. NYCERS USE ONLY Member Number Last 4 Digits of Social Security # Date of Birth [MM/DD/YYYY

    E-print Network

    Rosen, Jay

    R04/01/12 NYCERS USE ONLY Member Number Last 4 Digits of Social Security # Date of Birth [MM Address Apt. Number City State Zip Code Full Social Security Number Date of Birth [MM on Form 137 / / Full Social Security Number Date of Birth [MM/DD/YYYY] Relationship / / / / #12;R04

  11. PhET Teacher Activities: Hooke's Law

    NSDL National Science Digital Library

    2012-09-25

    This two-hour activity for high school physics was created to accompany the PhET simulation Masses & Springs. In the first lesson, students will use the simulation to explore how displacement of a spring is mathematically related to the load applied to it. In the next day's exploration, learners analyze the energy of a mass oscillating on a spring by observing distribution and transfer of kinetic, elastic potential, and gravitational potential energy. Materials include learning goals, explicit directions for use of the simulation, homework problems, and answer key. The spring motion simulation (which is required to complete this activity) is available from PhET at: Masses & Springs. This lesson is part of the PhET (Physics Education Technology Project), a large collection of free interactive science simulations.

  12. Effect of pH on the accumulation kinetics of pentachlorophenol in goldfish

    USGS Publications Warehouse

    Stehly, G.R.; Hayton, W.L.

    1990-01-01

    The kinetics of accumulation of pentachlorophenol (PCP) at various pH values were investigated to explore how pH-dependent accumulation might influence PCP toxicity. Goldfish (Carassius auratus ) were exposed to 5 mu g PCP/L in a static system buffered with 7.5 mM bicine or N,N-bis(2-hydroxyethyl)-2-aminoethane sulfonic acid (BES) at pH 7.0, 8.0, or 9.0. The amount of PCP in the fish, concentration of PCP in water, and the total amount of metabolites in the system were measured after exposure of fish from 1 to 96 hr. The distribution of PCP within the fish was altered by changes in the external pH. The pH-associated changes in distribution may have altered access of PCP to sites of metabolism, thereby altering the metabolic clearance. The pH-related changes in the pharmacokinetics of PCP resulted in a decrease in its bioconcentration factor with an increase in pH and account both for the decreased capacity of the fish to accumulated PCP and for its reduced LC50.

  13. Is there a critical tissue oxygen tension for bioenergetic status and cellular pH regulation in solid tumors?

    Microsoft Academic Search

    P. Vaupel

    1996-01-01

    Bioenergetic and metabolic status have been correlated with tissue oxygenation in murine fibrosarcomas (FSaII) of varying sizes (44–600 mm3). Ratios of ?-nucleoside triphosphates to inorganic phosphate (?NTP\\/Pi) and phosphocreatine to inorganic phosphate (PCr\\/Pi) ratios derived from31P nuclear magnetic resonance spectroscopy (NMR) were positively correlated to median tissue O2 tension (pO2) values using O2-sensitive needle electrodes. pH declined during growth with

  14. College of Education PhD in Education

    E-print Network

    Van Stryland, Eric

    1 College of Education PhD in Education Exceptional Education Track Handbook A guide for doctoral students pursuing the PhD in Exceptional Education Lisa Dieker, PhD Wilfred Wienke, PhD Project LEAD ­ Leadership in Exceptional Education Advancing Diversity #12;2 Manuscript Preparation (2008) Kimberly Pawling

  15. 2011 Cecilia J. Hillard, PhD Douglas R. Campbell

    E-print Network

    2007 Jane Morley Kotchen, MD, MPH Julian H. Lombard, PhD Robert L. Truitt, PhD 2006 Mary Horowitz, MD Fujimoto, PhD Edward Stewart, MD Stuart Wilson, MD 1995 Charles Aprahamian, MD Walter Hogan, MD Neil Mandel, PhD 1994 Michael Keelan, Jr., MD Roland Pattillo, MD Jonathan Towne, MD 1993 James Cerletty, MD

  16. MD/PhD Program "Molecular Medicine" Hannover Medical School

    E-print Network

    Manstein, Dietmar J.

    __________________________________________________________________ 14 4. Organization of Educational Material________________________________________________ 15 5#12;#12;MD/PhD Program "Molecular Medicine" Hannover Medical School Report 2005 #12;#12;MD/Ph Chairman MD/PhD Program Carl-Neuberg Str. 1 30625 Hannover Tel: 0511-532-6656 immunologie@mh-hannover.de MD/Ph

  17. PH DEPENDENT TOXICITY OF FIVE METALS TO THREE MARINE ORGANISMS

    EPA Science Inventory

    The pH of natural marine systems is relatively stable; this may explain why metal toxicity changes with pH have not been well documented. However, changes in metal toxicity with pH in marine waters are of concern in toxicity testing. During porewater toxicity testing pH can chang...

  18. pH and Titratable Acidity

    NASA Astrophysics Data System (ADS)

    Sadler, George D.; Murphy, Patricia A.

    There are two interrelated concepts in food analysis that deal with acidity: pH and titratable acidity. Each of these quantities is analytically determined in separate ways and each has its own particular impact on food quality. Titratable acidity deals with measurement of the total acid concentration contained within a food (also called total acidity). This quantity is determined by exhaustive titration of intrinsic acids with a standard base. Titratable acidity is a better predictor of acid's impact on flavor than pH.

  19. Electrochemiluminescent pH sensor measured by the emission potential of TiO2 nanocrystals and its biosensing application.

    PubMed

    Liu, Xuan; Wang, Nianyue; Zhao, Wei; Jiang, Hui

    2015-02-01

    This work reports for the first time a potential-based nano-electrochemiluminescent (ECL) pH sensor, using anatase TiO2 nanocrystals (NCs) as the ECL probe. The first ECL peak potential of the TiO2 NCs shifted negatively with increasing pH, showing a linear range from -0.47 V (vs Ag/AgCl) at pH 3 to -1.06 V at pH 10. This phenomenon was attributed to the absorption of 'potential-determining ions' of OH(-) on the surface of TiO2 NCs, leading to larger impedance of the electron injection. Other common 'potential-determining ions', such as phosphate, induced a slight potential shift of 0.03 V at a concentration of 0.1 M. Using urease as an enzyme model, a urea biosensor was developed by the simultaneous modification of urease and TiO2 NCs on indium-tin oxide (ITO) electrodes. The biosensor, measured on the basis of the pH increase caused by the enzyme catalysis reaction, had a linear range of 0.01-2.0 mM, with a potential shift of 0.175 V. The as-prepared pH sensor, which has simple construction procedures and acceptable sensitivity and selectivity, may provide new avenues for the construction of ECL bioanalytical methodologies. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24802560

  20. Peritoneal dialysis solution pH and Ca2+ concentration regulate peritoneal macrophage and mesothelial cell activation.

    PubMed

    Carozzi, S; Caviglia, P M; Nasini, M G; Schelotto, C; Santoni, O; Pietrucci, A

    1994-01-01

    We evaluated the in vitro effects of pH and Ca2+ concentration of peritoneal dialysis solution (PDS) on (1) the release of interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-8 (IL-8) from peritoneal macrophages (PM0) and peritoneal mesothelial cells (PMC); (2) the release of IL-6 and IL-8 by PMC; and (3) the PM0 and PMC intracellular Ca2+ concentration. Aliquots of 5 x 10(6) PM0 and PMC were incubated (2 hr, 37 degrees C) in 1 ml of physiologic growth medium (RPMI 1640) and in 1 ml of four different PDS (1.36 g/dl glucose): (1) type A PDS (pH 5.5, Ca2+ 1.75 mM), (2) type B PDS (pH 5.5, Ca2+ 1.25 mM), (3) type C PDS (bicarbonate buffered pH 7.4, Ca2+ 1.75 mmol/L, and (4) type D PDS (bicarbonate buffered pH 7.4, Ca2+ 1.25 mM); each was stimulated with S. epidermidis. Results showed that type A PDS samples induced an average 60% increase in PM0 and PMC cytoplasmic levels and in cytokine release, whereas with type B PDS samples there was a 90% decrease. Type C PDS samples did not modify the PM0 and PMC IL-6 and IL-8 production, whereas a 3-fold rise in the production of IL-1 and TNF-alpha by PM0 was seen; this was associated with an increase in PM0 and PMC Ca2+ cytoplasmic levels. When type D PDS samples were incubated, however, there was an average 40% decrease in PM0 and PMC cytoplasmic Ca2+ levels and in cytokine release.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8186487

  1. Role of bicarbonate as a pH buffer and electron sink in microbial dechlorination of chloroethenes

    PubMed Central

    2012-01-01

    Background Buffering to achieve pH control is crucial for successful trichloroethene (TCE) anaerobic bioremediation. Bicarbonate (HCO3?) is the natural buffer in groundwater and the buffer of choice in the laboratory and at contaminated sites undergoing biological treatment with organohalide respiring microorganisms. However, HCO3? also serves as the electron acceptor for hydrogenotrophic methanogens and hydrogenotrophic homoacetogens, two microbial groups competing with organohalide respirers for hydrogen (H2). We studied the effect of HCO3? as a buffering agent and the effect of HCO3?-consuming reactions in a range of concentrations (2.5-30 mM) with an initial pH of 7.5 in H2-fed TCE reductively dechlorinating communities containing Dehalococcoides, hydrogenotrophic methanogens, and hydrogenotrophic homoacetogens. Results Rate differences in TCE dechlorination were observed as a result of added varying HCO3? concentrations due to H2-fed electrons channeled towards methanogenesis and homoacetogenesis and pH increases (up to 8.7) from biological HCO3? consumption. Significantly faster dechlorination rates were noted at all HCO3? concentrations tested when the pH buffering was improved by providing 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as an additional buffer. Electron balances and quantitative PCR revealed that methanogenesis was the main electron sink when the initial HCO3? concentrations were 2.5 and 5 mM, while homoacetogenesis was the dominant process and sink when 10 and 30 mM HCO3? were provided initially. Conclusions Our study reveals that HCO3? is an important variable for bioremediation of chloroethenes as it has a prominent role as an electron acceptor for methanogenesis and homoacetogenesis. It also illustrates the changes in rates and extent of reductive dechlorination resulting from the combined effect of electron donor competition stimulated by HCO3? and the changes in pH exerted by methanogens and homoacetogens. PMID:22974059

  2. Lawrence Goldstein, Ph.D.Adah Almutairi, Ph.D.Steffanie Strathdee, Ph.D. Tackling Alzheimer's With

    E-print Network

    Cai, Long

    's With Stem Cells Lawrence Goldstein, Ph.D., director of the new Sanford Stem Cell Clinical Center, stem cell-derived models of sporadic and hereditary Alzheimer's disease using induced pluripotent stem cells from patients with AD. These functional neurons in a dish promise to be an unprecedented tool

  3. Inactivation of adenovirus, reovirus and bacteriophages in fecal sludge by pH and ammonia.

    PubMed

    Magri, Maria Elisa; Fidjeland, Jørgen; Jönsson, Håkan; Albihn, Ann; Vinnerås, Björn

    2015-07-01

    The aim of this study was to evaluate the inactivation of adenovirus, reovirus and bacteriophages (MS2, ?X174, 28B) in a fecal sludge. We conducted two experiments. In the first, we tested different compositions of the fecal sludge by mixing different amounts of water, feces and urine, totaling nine combinations which were kept at temperatures between 10 and 28°C. In the second study, urea was added to the mixtures, which were kept at temperatures from 5 to 33°C. The inactivation was based on a combination of temperature, pH and uncharged ammonia concentration. The increase in pH and ammonia was provided mainly by urine content (Experiment 1) and by urine and added urea (Experiment 2). The inactivation of bacteriophages was slower than the AdV and ReV. At 23°C and 28°, reasonable treatment times were obtained when pH was higher than 8.9 and NH3 concentrations were higher than 35 and 55mM respectively. With those conditions, the maximum time for a 3 log reduction in viruses, according to this study, would be 35days (23°C) and 21days (28°C). However, in most applications where helminth eggs are present, the treatment time and NH3 for sanitization will be the scaling criteria, as they are more persistent. Concerning the sanitization of effluents from latrines, vacuum toilets or dry toilets in developing countries with tropical and sub-tropical climates, the use of intrinsic ammonia combined with high pH can be effective in producing a safe and highly valuable liquid that can be used as a fertilizer. In the case of the fecal sludge with very intrinsic ammonia concentration (<20mM), sanitization could still be achieved by the addition of urea. PMID:25817758

  4. Machine Design -2 Consider a machined 60mm diameter shaft made of AISI 1020 HR (Sut = 380 MPa at 20C) quenched

    E-print Network

    Virginia Tech

    into the shaft to seat an O-ring. The shaft is rotated in an operating environment of 270°C where the torque at each of the points using the Gerber failure criteria. 150 mm 200 mm 100 mm r = 3 mm 60 mm 110 mm

  5. The Influence of pH on the Oxygen Isotope Composition of Calcium Carbonate

    NASA Astrophysics Data System (ADS)

    Hunt, J. D.; Watkins, J. M.; Ryerson, F. J.; DePaolo, D. J.

    2013-12-01

    Oxygen isotope fractionation between calcium carbonate and water is temperature-dependent and can therefore be used as a paleothermometer. Although oxygen isotope fractionation is expected from principles of equilibrium isotopic partitioning, the temperature-dependence remains uncertain because other factors, such as slow exchange between dissolved inorganic carbon (DIC) species and water, can obscure the temperature signal. Oxygen isotopic equilibrium between aqueous solution and calcium carbonate includes two distinct equilibria: equilibrium of the DIC species in solution (i.e., CO2(aq), H2CO3, HCO3-, and CO32-) with water, and equilibrium between the dissolved inorganic carbon with the precipitated carbonate. To isolate kinetic isotope effects that arise at the mineral-solution interface, isotopic equilibrium among DIC species must be maintained. This can be accomplished by dissolving the enzyme carbonic anhydrase (CA) into the solution, thereby reducing the time required for isotopic equilibration between DIC species by approximately two orders of magnitude between pH 7.7 and 9.3. We conduct calcite growth experiments aimed specifically at measuring the pH-dependence of kinetic oxygen isotope effects during precipitation of calcite. We precipitated calcite from aqueous solution at a constant pH and controlled supersaturation over the pH range 7.7-9.3. For each experiment, a gas mixture of N2 and CO2 is constantly bubbled through a beaker containing ~1300 mL of solution (30 mM CaCl2 + 5 mM NH4Cl + 0.1 mM SrCl2). As CO2 from the gas dissolves into solution, calcite crystals grow on the beaker walls. The pH of the solution is maintained by use of an autotitrator with NaOH as the titrant. We control the temperature, pH, the pCO2 of the gas inflow, and the gas inflow rate, and monitor the total alkalinity, the pCO2 of the gas outflow, and the amount of NaOH added. A constant crystal growth rate of ~1.6 mmol/m2/hr is maintained over all experiments. We will present results from this set of experiments and discuss kinetic oxygen isotope effects in the context of a recently-developed ion-by-ion growth model of calcite.

  6. Comparison of 16 mm OSU-Nag and COMS eye plaques.

    PubMed

    Zhang, Hualin; Davidorf, Frederick; Qi, Yujin

    2012-01-01

    OSU-NAG eye plaques use fewer sources than COMS-plaques of comparable size, and do not employ a Silastic seed carrier insert. Monte Carlo modeling was used to calculate 3D dose distributions for a 16 mm OSU-NAG eye plaque and a 16 mm COMS eye plaque loaded with either Iodine-125 or Cesium-131 brachytherapy sources. The OSU-NAG eye plaque was loaded with eight sources forming two squares, whereas the COMS eye plaque was loaded with thirteen sources approximating three isocentric circles. A spherical eyeball 24.6 mm in diameter and an ellipsoid-like tumor 6 mm in height and 12 mm in the major and minor axes were used to evaluate the doses delivered. To establish a fair comparison, a water seed carrier was used instead of the Silastic seed carrier designed for the traditional COMS eye plaque. Calculations were performed on the dose distributions along the eye plaque axis and the DVHs of the tumor, as well as the 3D distribution. Our results indicated that, to achieve a prescription dose of 85 Gy at 6 mm from the inner sclera edge for a six-day treatment, the OSU-NAG eye plaque will need 6.16 U/source and 6.82U/source for 125I and 131Cs, respectively. The COMS eye plaque will require 4.02 U/source and 4.43 U/source for the same source types. The dose profiles of the two types of eye plaques on their central axes are within 9% difference for all applicable distances. The OSU-NAG plaque delivers about 10% and 12% more dose than the COMS for 125I and 131Cs sources, respectively, at the inner sclera edge, but 6% and 3% less dose at the opposite retina. The DVHs of the tumor for two types of plaques were within 6% difference. In conclusion, the dosimetric quality of the OSU-NAG eye plaque used in eye plaque brachytherapy is comparable to the COMS eye plaque. PMID:22584165

  7. Station-based verification of qualitative and quantitative MM5 precipitation forecasts over Northwest Himalaya (NWH)

    NASA Astrophysics Data System (ADS)

    Singh, Dan; Bhutiyani, M. R.; Ram, Tule

    2014-08-01

    Weather forecasts by any forecast system are verified using either distributions-oriented or measures-oriented forecast verification measures. Both the forecast verification schemes represent different aspects of the forecast quality, and advantages of them can be utilized to get better insight and to identify particular strengths (deficiencies) in the forecast performance of any forecast system. Keeping this in view, multi-faced verification (binary and continuous) of quantitative precipitation forecasts for consecutive 3 days by a Regional Meso-scale Weather Simulation Model (MM5 Model) has been carried out to get complete insight into its performance. The MM5 model forecasts at 10-km resolution for 792 days of six winters (winter 2003/2004 to winter 2008/2009) are compared with the observational data of six stations in the complex topography of Northwest Himalaya (NWH) in India. The model forecasts are verified using binary categorical forecast verification measures such as Probability of Detection, False Alarm Rate, Miss Rate, Correct Non-occurrence, Critical Success Index and Percent correct, and continuous forecast verification measures such as Mean Absolute Error (MAE) and Root Mean Square Error (RMSE). BIAS is computed to know over-forecast/under-forecast tendency of a precipitation day (PT day) by the MM5 model. MAE (RMSE) of the MM5 model is computed separately for all days, PT days and no precipitation days (NPT days). MAE (RMSE) of PT days is found to be relatively larger as compared to NPT days and all days. These findings indicate that MAE (RMSE) computed separately for all days, PT days and NPT days provides better insight into the performance of the MM5 model. Results also suggest that the MM5 model shows reasonably good performance for binary forecasts (PT days/NPT days) for day 1 (0-24 h), day 2 (24-48 h) and day 3 (48-72 h). However, large errors are seen in predicting the observed precipitation amount of PT days over NWH.

  8. Accelerating QM/MM Free Energy Calculations: Representing the Surroundings by an Updated Mean Charge Distribution

    PubMed Central

    Rosta, Edina; Haranczyk, Maciej; Chu, Zhen T.; Warshel, Arieh

    2009-01-01

    Reliable studies of enzymatic reactions by combined quantum mechanical /molecular mechanics (QM(ai)/MM) approaches, with an ab initio description of the quantum region, presents a major challenge to computational chemists. The main problem is the need for very large computer time to evaluate the QM energy, which in turn makes it extremely challenging to perform proper configurational sampling. One of the most obvious options for accelerating QM/MM simulations is the use of an average solvent potential. In fact the idea of using an average solvent potential is rather obvious and has implicitly been used in Langevin dipole / QM calculations. However, in the case of explicit solvent models the practical implementations are more challenging and the accuracy of the averaging approach has not been validated. The present study introduces the average effect of the fluctuating solvent charges by using equivalent charge distributions, which are updated every m steps. Several models are evaluated in terms of the resulting accuracy and efficiency. The most effective model divides the system into an inner region with N explicit solvent atoms and an external region with two effective charges. Different models are considered in terms of the division of the solvent system and the update frequency. Another key element of our approach is the use of the free energy perturbation (FEP) and/or linear response approximation (LRA) treatments that guarantees the evaluation of the rigorous solvation free energy. Special attention is paid to the convergence of the calculated solvation free energies and the corresponding solute polarization. The performance of the method is examined by evaluating the solvation of a water molecule and a formate ion in water and also the dipole moment of water in water solution. Remarkably, it is found that different averaging procedures eventually converge to the same value but some protocols provide optimal ways of obtaining the final QM(ai)/MM converged results. The current method can provide computational time saving of 1000 for properly converging simulations relative to calculations that evaluate the QM(ai)/MM energy every time step. A specialized version of our approach that starts with a classical FEP charging and then evaluates the free energy of moving from the classical potential to the QM/MM potential appears to be particularly effective. This approach should provide a very powerful tool for QM(ai)/MM evaluation of solvation free energies in aqueous solutions and proteins. PMID:18412414

  9. The W43-MM1 mini-starburst ridge, a test for star formation efficiency models

    NASA Astrophysics Data System (ADS)

    Louvet, F.; Motte, F.; Hennebelle, P.; Maury, A.; Bonnell, I.; Bontemps, S.; Gusdorf, A.; Hill, T.; Gueth, F.; Peretto, N.; Duarte-Cabral, A.; Stephan, G.; Schilke, P.; Csengeri, T.; Nguyen Luong, Q.; Lis, D. C.

    2014-10-01

    Context. Star formation efficiency (SFE) theories are currently based on statistical distributions of turbulent cloud structures and a simple model of star formation from cores. They remain poorly tested, especially at the highest densities. Aims: We investigate the effects of gas density on the SFE through measurements of the core formation efficiency (CFE). With a total mass of ~2 × 104 M?, the W43-MM1 ridge is one of the most convincing candidate precursors of Galactic starburst clusters and thus one of the best places to investigate star formation. Methods: We used high-angular resolution maps obtained at 3 mm and 1 mm within the W43-MM1 ridge with the IRAM Plateau de Bure Interferometer to reveal a cluster of 11 massive dense cores, and, one of the most massive protostellar cores known. A Herschel column density image provided the mass distribution of the cloud gas. We then measured the "instantaneous" CFE and estimated the SFE and the star formation rate (SFR) within subregions of the W43-MM1 ridge. Results: The high SFE found in the ridge (~6% enclosed in ~8 pc3) confirms its ability to form a starburst cluster. There is, however, a clear lack of dense cores in the eastern part of the ridge, which may be currently assembling. The CFE and the SFE are observed to increase with volume gas density, while the SFR per free fall time steeply decreases with the virial parameter, ?vir. Statistical models of the SFR may describe the outskirts of the W43-MM1 ridge well, but struggle to reproduce its inner part, which corresponds to measurements at low ?vir. It may be that ridges do not follow the log-normal density distribution, Larson relations, and stationary conditions forced in the statistical SFR models. Final IRAM/PdBI FITS cube is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/570/A15

  10. A emissão em 8mm e as bandas de Merrill-Sanford em estrelas carbonadas

    NASA Astrophysics Data System (ADS)

    de Mello, A. B.; Lorenz-Martins, S.

    2003-08-01

    Estrelas carbonadas possuem bandas moleculares em absorção no visível e, no infravermelho (IR) as principais características espectrais se devem a emissão de grãos. Recentemente foi detectada a presença de bandas de SiC2 (Merrill-Sanford, MS) em emissão sendo atribuída à presença de um disco rico em poeira. Neste trabalho analisamos uma amostra de 14 estrelas carbonadas, observadas no telescópio de 1.52 m do ESO em 4 regiões espectrais diferentes, a fim de detectar as bandas de MS em emissão. Nossa amostra é composta de estrelas que apresentam além da emissão em 11.3 mm, outra em 8 mm. Esta última emissão, não usual nestes objetos, tem sido atribuída ou a moléculas de C2H2, ou a um composto sólido ainda indefinido. A detecção de emissões de MS e aquelas no IR, simultaneamente, revelaria um cenário mais complexo que o habitualmente esperado para os ventos destes objetos. No entanto como primeiro resultado, verificamos que as bandas de Merrill-Sanford encontram-se em absorção, não revelando nenhuma conexão com a emissão a 8 mm. Assim, temos duas hipóteses: (a) a emissão a 8 mm se deve à molécula C2H2 ou (b) essa emissão é resultado da emissão térmica de grãos. Testamos a segunda hipótese modelando a amostra com grãos não-homogêneos de SiC e quartzo, o qual emite em aproximadamente 8mm. Este grão seria produzido em uma fase evolutiva anterior a das carbonadas (estrelas S) e por terem uma estrutura cristalina são destruídos apenas na presença de campos de radiação ultravioleta muito intensos. Os modelos para os envoltórios utilizam o método de Monte Carlo para descrever o problema do transporte da radiação. As conclusões deste trabalho são: (1) as bandas de Merrill-Sanford se encontram em absorção, sugerindo um cenário usual para os ventos das estrelas da amostra; (2) neste cenário, a emissão em 8 mm seria resultado de grãos de quartzo com mantos de SiC, indicando que o quartzo poderia sobreviver a fase evolutiva S.

  11. Transcription of denitrification genes and kinetics of NO, N2O and N2 by soil bacteria as affected by pH

    NASA Astrophysics Data System (ADS)

    Liu, B.; Bakken, L. R.; Frostegard, A.

    2010-12-01

    Nitrous oxide (N2O), which is to a large part derived from denitrification in soil, is a major greenhouse gas and was also recently shown to be the single most important ozone-depleting substance. Previous studies demonstrate that the N2O/N2 product ratio of denitrification is strongly dependent on pH, increasing with decreasing soil pH. The mechanisms involved are, however, poorly understood. We here present an investigation of soils from a long-term liming experiment. Since it is difficult to control which pH is actually experienced by bacterial cells in intact soils, we extracted cells on a Nycodenz gradient and exposed them to different pH levels. Bacteria extracted from soils of 3 different pHs (4.0, 6.1 and 8.0) were incubated in minimal medium supplemented with nitrate (2mM) and glutamic acid (5 mM), buffered at three pH levels (5.7, 6.1 and 7.6). Both the pH of the medium and original soil pH showed profound effect on the denitrification activity in terms of gas emission kinetics. N2O reductase (N2OR) activity was only present when cells from the high pH soils (pH 6.1 and 8.0) were exposed to high pH medium (pH 7.6). Functional genes (nirS, nirK and nosZ) and their transcripts were quantified in the extracts from pH6.1-soil. A 10-25 fold higher expression of nosZ vs nirS was found when incubated at pH 7.6 compared to pH 6.1 and 5.7. The low but significant transcription of nosZ at pH 6.1 and 5.7 did not result in detectable N2O reduction however. Cells that had been allowed to assemble their proteome while growing in pH7 medium showed N2OR activity which was practically unaffected by pH within the range 5-7. On the contrary, no N2OR activity was detected if the proteome had been formed at pH 6. The cells extracted from acid soils (pH 5.8 and 6.1) showed very low nosZ transcritption and no N2OR activity if exposed to pH 7 during the transition from oxic to anoxic conditions, suggesting an adaptation to low pH in the sense that they do not transcribe the gene for N2OR. This could be an advantage, since the chances of producing a functional N2OR enzymes are meager at that pH. The results demonstrated that low pH has profound effect on the relative activity of the N2OR in soil bacterial communities, by interference both at transcriptional and post transcriptional level, but not by a direct effect on the successfully assembled enzyme. In other words, the frequently observed high N2O/N2 product ratio of denitrification in acid soils is not due to a direct effect on the activity of the N2O reductase enzyme.

  12. Instrument development and field application of the in situ pH Calibrator at the Ocean Observatory

    NASA Astrophysics Data System (ADS)

    Tan, C.; Ding, K.; Seyfried, W. E.

    2012-12-01

    A novel, self-calibrating instrument for in-situ measurement of pH in deep sea environments up to 4000 m has recently been developed. The device utilizes a compact fluid delivery system to perform measurement and two-point calibration of the solid state pH sensor array (Ir|IrOx| Ag|AgCl), which is sealed in a flow cell to enhance response time. The fluid delivery system is composed of a metering pump and valves, which periodically deliver seawater samples into the flow cell to perform measurements. Similarly, pH buffer solutions can be delivered into the flow cell to calibrate the electrodes under operational conditions. Sensor signals are acquired and processed by a high resolution (0.25 mV) datalogger circuit with a size of 114 mm×31 mm×25 mm. Eight input channels are available: two high impedance sensor input channels, two low impedance sensor input channel, two thermocouple input channels and two thermistor input channels. These eight channels provide adequate measurement flexibility to enhance applications in deep sea environments. The two high impedance channels of the datalogger are especially designed with the input impedance of 1016 ? for YSZ (yittria-stabilized zirconia) ceramic electrodes characterized by the extremely low input bias current and high resistance. Field tests have been performed in 2008 by ROV at the depth up to 3200 m. Using the continuous power supply and TCP/IP network capability of the Monterey Accelerated Research System (MARS) ocean observatory, the so-called "pH Calibrator" has the capability of long term operation up to six months. In the observatory mode, the electronics are configured with DC-DC power converter modules and Ethernet to serial module to gain access to the science port of seafloor junction box. The pH Calibrator will be deployed at the ocean observatory in October and the in situ data will be on line on the internet. The pH Calibrator presents real time pH data at high pressures and variable temperatures, while the in situ calibration capability enhances the accuracy of electrochemical measurements of seawater pH, fulfilling the need for long term objectives for marine studies.

  13. Tiffany Niemoller Eady, Ph.D. Major Professor: Nicolas G. Bazan, M.D., Ph.D.

    E-print Network

    Functionality May, 2007 Fang Liu, M.S. Major Professor: Miguel Pappolla, M.D., Ph.D. Dissertation: ContributionMay, 2011 Tiffany Niemoller Eady, Ph.D. Major Professor: Nicolas G. Bazan, M.D., Ph.D. Dissertation: Docosahexaenoic Acid, Neurolipidomics, and the Ischemic Penumbra of Stroke Hongbo He, Ph.D. Major Professor

  14. Roadmap: Public Health-Allied Health-Bachelor of Science in Public Health [PH-BSPH-PH-AHLT

    E-print Network

    Sheridan, Scott

    Semester Seven: [12 Credit Hours] PH 30002 Introductory Biostatistics 3 PH 44000 Health Disparities 3 CRoadmap: Public Health-Allied Health-Bachelor of Science in Public Health [PH-BSPH-PH-AHLT] College of Public Health Catalog Year: 2012-2013 Page 1 of 2 | Last Updated: 10-Apr-12/LNHD This roadmap

  15. Stress corrosion study of PH13-8Mo stainless steel using the Slow Strain Rate Technique

    NASA Technical Reports Server (NTRS)

    Torres, Pablo D.

    1989-01-01

    The need for a fast and reliable method to study stress corrosion in metals has caused increased interest in the Slow Strain Rate Technique (SSRT) during the last few decades. PH13-8MoH950 and H1000 round tensile specimens were studied by this method. Percent reduction-in-area, time-to-failure, elongation at fracture, and fracture energy were used to express the loss in ductility, which has been used to indicate susceptibility to stress corrosion cracking (SCC). Results from a 3.5 percent salt solution (corrosive medium) were compared to those in air (inert medium). A tendency to early failure was found when testing in the vicinity of 1.0 x 10(-6) mm/mm/sec in the 3.5 percent salt solution. PH13-8Mo H1000 was found to be less likely to suffer SCC than PH13-8Mo H950. This program showed that the SSRT is promising for the SCC characterization of metals and results can be obtained in much shorter times (18 hr for PH steels) than those required using conventional techniques.

  16. Investigate the MM5 model ability to simulate and predict convective precipitation over soutwest of Iran

    NASA Astrophysics Data System (ADS)

    Ghandhari, S.; Meshkatee, A.; Mazraee Farahani, M.; Jafari, S.; Khazanehdari, L.

    2009-09-01

    Among weather phenomena, convection, due to its complexity and destructive nature, has been subject of many studies and researches through out the world. For decades, generating different types of models were attempted by scientists to provide possibility of abating or at least reducing convective weather phenomena effects on people's life. People in south and southwest of Iran are familiar with convective phenomena and their effects. Due to Socio-Economic importance of convective phenomena and availability of a meso-scale (MM5) model in Iranian meteorological Organization it has been tried to investigate the model ability to simulate and to predict convective precipitation in south and southwest of the country. Outcome of the study indicates that the model produces acceptable results on convection that arises from sharp baroclinic conditions; but it has failed to produce acceptable results where convection is due to local conditions. Keywords: Convection, Numerical Weather Prediction, MM5 model, Baroclinic

  17. Bitter magnet system 13 T. -125 mm. bore usable for investigations at 1. 8 K

    SciTech Connect

    Claudet, G.; Rub, P.; Vallier, J.C.

    1981-09-01

    A cryomagnetic system is described for superconducting materials submitted to an external field for two temperatures: 1.8 K and 4.2 K. The originality of the system is to obtain 1.8 K at atmospheric pressure. The system is made of two distinct parts: A bitter coil, with a nominal power of 10 mw allowing one to obtain more than 13T in a clear bore of 160 mm at room temperature; a cryostat in which it is possible to insert cylindrical elements with a diam of 125 mm, equipped with appliances allowing either a traditional use or use of superfluid helium at atmospheric pressure. This material was built to allow stability experiments in superconducting samples as well as significant length tests of commercial superconducting materials. 8 refs.

  18. Survival and photoreactivability of ultraviolet-irradiated cultured fish cells (CAF-MM1)

    SciTech Connect

    Mano, Y. (Univ. of Tokyo, Hongo); Mitani, H.; Etoh, H.; Egami, N.

    1980-12-01

    The sensitivity to ultraviolet light (uv) and photoreactivating ability of cultured fish clone cells (CAF-MM1) were investigated. Dose-survival relationship curves were obtained using the colony-forming technique at various postirradiation temperatures (33, 26, and 20/sup 0/C). At 26/sup 0/C the values of D/sub 0/, D/sub q/, and the extrapolation number (n) were 1.74 J/m/sup 2/, 2.62 J/m/sup 2/, and 4.5, respectively; no marked differences in these values were found among different temperatures. Visible light illumination after uv irradiation produced a marked increase in survival. No photoreactivation effects were observed beyond about 30 h. Caffeine increased uv sensitivity of the CAF-MM1 cells, and from the results it is suggested that the cells have some caffeine-sensitive dark repair mechanisms.

  19. A 3mm band SIS receiver for the Sardinia Radio Telescope

    NASA Astrophysics Data System (ADS)

    Ladu, A.; Pisanu, T.; Navarrini, A.; Marongiu, P.; Valente, G.

    2014-07-01

    We present the optical and mechanical design of a 3mm band SIS receiver for the Gregorian focus of the Sardinia Radio Telescope (SRT). The receiver, was designed and built at IRAM and deployed on the IRAM for the Plateau de Bure Interferometer antennas until 2006. Following its decommissioning the receiver was purchased by the INAFAstronomical Observatory of Cagliari with the aim to adapt its optics for test of the performance of the new 64-m diameter Sardinia Radio Telescope (SRT) in the 3 mm band (84 - 116 GHz). The instrument will be installed in the rotating turret inside of the Gregorian focal room of SRT. The dimensions of the focal room, the horn position in the lower side of the cryostat and the vessel for the liquid helium impose very hard constraints to the optical and mechanical mounting structure of the receiver inside the cabin. We present the receiver configuration and how we plan to install it on SRT.

  20. THE MAGNETIC FIELD MORPHOLOGY OF THE CLASS 0 PROTOSTAR L1157-mm

    SciTech Connect

    Stephens, Ian W.; Looney, Leslie W.; Kwon, Woojin; Crutcher, Richard M. [Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, IL 61801 (United States); Hull, Charles L. H.; Plambeck, Richard L. [Astronomy Department and Radio Astronomy Laboratory, 601 Campbell Hall, University of California, Berkeley, CA 94720 (United States); Chapman, Nicholas; Novak, Giles; Matthews, Tristan [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Davidson, Jacqueline [School of Physics, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009 (Australia); Vaillancourt, John E. [SOFIA Science Center, Universities Space Research Association, NASA Ames Research Center, MS 232-11, Moffett Field, CA 94035-0001 (United States); Shinnaga, Hiroko, E-mail: stephen6@illinois.edu [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A'ohoku Place, Hilo, HI 96720 (United States)

    2013-05-20

    We present the first detection of polarization around the Class 0 low-mass protostar L1157-mm at two different wavelengths. We show polarimetric maps at large scales (10'' resolution at 350 {mu}m) from the SHARC-II Polarimeter and at smaller scales (1.''2-4.''5 at 1.3 mm) from the Combined Array for Research in Millimeter-wave Astronomy (CARMA). The observations are consistent with each other and show inferred magnetic field lines aligned with the outflow. The CARMA observations suggest a full hourglass magnetic field morphology centered about the core; this is only the second well-defined hourglass detected around a low-mass protostar to date. We apply two different methods to CARMA polarimetric observations to estimate the plane-of-sky magnetic field magnitude, finding values of 1.4 and 3.4 mG.

  1. High- and Mid-temperature Superconducting Sensors for Far IR/Sub-mm Applications in Space

    NASA Technical Reports Server (NTRS)

    Lakew, Brook; Brasunas, J. C.

    2004-01-01

    In this review paper an overview of the potential applications of high Tc (approx. 90 K) superconductors (HTS) and mid-Tc (approx. 39 K) superconductors (MTS) thin films in far IR/Sub-mm thermal detectors is presented. HTSs (YBCO, GdBCO etc.) were discovered in the late 80s while superconductivity in MgB2, an MTS, was discovered in 2001. The sharp transition in transport properties of HTS has allowed the fabrication of composite infrared thermal detectors (bolometers) with better figures of merit than thermopile detectors - thermopiles are currently on board the CIRS instrument on the Cassini mission to Saturn. The potential for developing even more sensitive sensors for IR/Sub-mm applications using MgB2 thin films is assessed. Current MgB2 thin film deposition techniques and film quality are reviewed.

  2. HELGA: The Herschel Exploitation of the Local Galaxy Andromeda: Sub-mm Morphology and Dust Properties

    NASA Astrophysics Data System (ADS)

    Fritz, J.; Smith, M. W. L.; Kirk, J.; Helga Collaboration

    2014-03-01

    The results from a large-field Far-Infrared (FIR) and sub-millimeter (sub-mm) survey of our neighbor galaxy M31 are presented. We have obtained Herschel images of a ˜ 5.5 × 2.5 degree area centered on Andromeda. Using 21-cm atomic hydrogen maps, we are able to disentangle genuine emission from M31 from that for foreground Galactic cirrus, allowing us to recognize dusty structures out to ˜ 31 kpc from the center. We first characterize the FIR and sub-mm morphology and then, by de-projecting Herschel maps and running an ad-hoc source extraction algorithm, we reconstruct the intrinsic morphology and the spatial distribution of the molecular complexes. Finally, we study the spatially resolved properties of the dust (temperature, emissivity, mass, etc.) by means of a pixel-by-pixel SED fitting approach.

  3. New grade of 9-inch size mask blanks for 450mm wafer process

    NASA Astrophysics Data System (ADS)

    Harashima, Noriyuki; Iso, Hiroyuki; Chishima, Tatsuya

    2014-10-01

    6-inch size (known as 6025QZ) binary Cr mask is widely used in the semiconductor lithography for over 20years. Recently for the 450mm wafer process, high grade 9-inch size mask is expected. For this application, we have studied and developed new grade 9-inch size mask blanks for recent 450mm wafer process requirement. There are three types of glass substrates material use and select as 9inch size mask blanks and for required applications by the users. Each glass material has advantage and disadvantage for lithography process as well as wafer process. By knowing the each glass substrate material characteristics and quality level the users enable to select the proper 9inch mask blanks for their targeting applications.

  4. A 2.5-mm diameter probe for photoacoustic and ultrasonic endoscopy

    PubMed Central

    Yang, Joon-Mo; Chen, Ruimin; Favazza, Christopher; Yao, Junjie; Li, Chiye; Hu, Zhilin; Zhou, Qifa; Shung, K. Kirk; Wang, Lihong V.

    2012-01-01

    We have created a 2.5-mm outer diameter integrated photo-acoustic and ultrasonic mini-probe which can be inserted into a standard video endoscope’s instrument channel. A small-diameter focused ultrasonic transducer made of PMN-PT provides adequate signal sensitivity, and enables miniaturization of the probe. Additionally, this new endoscopic probe utilizes the same scanning mirror and micromotor-based built-in actuator described in our previous reports; however, the length of the rigid distal section of the new probe has been further reduced to ~35 mm. This paper describes the technical details of the mini-probe and presents experimental results that both quantify the imaging performance and demonstrate its in vivo imaging capability, which suggests that it could work as a mini-probe for certain clinical applications. PMID:23188360

  5. 150MM diameter Nd:glass rod laser amplifier: characterization and prospects

    NASA Astrophysics Data System (ADS)

    Shaykin, Andrey; Soloviev, Alexander; Kuzmin, Alexey; Shaikin, Ilya; Burdonov, Konstantin; Khazanov, Efim

    2014-09-01

    We present the results of the investigation of a Nd:glass rod laser amplifier 320 mm long and 150 mm in diameter. The gain and depolarization distributions over the amplifier aperture as well as the stored energy have been measured for different values of the pump energy. The small signal gain averaged over the rod aperture was 2.3 when the pump energy was 48 kJ. The corresponding stored energy was 500 J. We have determined the maximal pulse repetition rate that is quiet safe from the point of the thermal shock damage. It is about 1 shot per 5 minutes. The calculated focal length of the thermal lens exceeds 1.5 km in such a regime. We have shown that the use of a couple of such amplifiers gives the possibility to increase the energy of laser pulses up to 650 J.

  6. LACTATE (mMol/L) MeanEtCO2(mmHg)

    E-print Network

    Wu, Shin-Tson

    .3 3.4 3.6 3.9 4.0 4.6 4.8 4.9 5.0 5.1 5.6 7.5 11.2 11.5 12.4 LACTATE (mMol/L) 0 10 20 30 40 50 MeanEtCO2(mmHg) VENOUS LACTATE .4 .5 .6 .7 .9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.5 2.6 2.8 11.4 11.7 15.0 LACTATE (mMol/L) 0 10 20 30 40 50 MeanEtCO2(mmHg) ARTERIAL LACTATE .4 .6 .8 1.0 1.2 1

  7. Use of 35-mm color aerial photography to acquire mallard sex ratio data

    USGS Publications Warehouse

    Ferguson, E.L.; Jorde, D.G.; Sease, J.L.

    1981-01-01

    A conventional 35-mm camera equipped with an f2.8 135-mm lens and ASA 64 color film was used to acquire sex ratio data on mallards (Anas platyrhynchos) wintering in the Platte River Valley of south-central Nebraska. Prelight focusing for a distance of 30.5 metres and setting of shutter speed at 1/2000 of a second eliminated focusing and reduced image motion problems and resulted in high-resolution, large-scale aerial photography of small targets. This technique has broad application to the problem of determining sex ratios of various species of waterfowl concentrated on wintering and staging areas. The aerial photographic method was cheaper than the ground ocular method when costs were compared on a per-100 bird basis.

  8. [Extracorporeal shockwave lithotripsy in the treatment of distal ureteral stones larger than 10 mm in diameter].

    PubMed

    Ishii, Nobuyuki; Yoshinaga, Atsushi; Ohno, Rena; Chiba, Koji; Hayashi, Tetsuo; Kamata, Shigeyoshi; Watanabe, Toru; Yamada, Takumi

    2004-06-01

    Optimal treatment for distal ureteral stones remains controversial. During a period of 10 years, from December 1992 to December 2002, 103 distal ureteral stones larger than 10 mm in diameter were treated at our institution with extracorporeal shock wave lithotripsy (ESWL) using the Siemens Lithostar. Only 2 patients had a ureteral stent in place at the time of treatment. The overall stone-free rate was 98% with 1-12 session and 3-month stone-free rate was 95.1%. These data reveal that a high success rate was achieved in multisession ESWL. Therefore, ESWL is considered to be acceptable as first-line therapy for fragmentation of distal ureteral stones larger than 10 mm in diameter. PMID:15293734

  9. A 3mm multipixel SIS receiver for IRAM 30-m Pico Veleta Telescope

    NASA Astrophysics Data System (ADS)

    Fontana, Anne-Laure; Boucher, Catherine; Serres, Patrice; Bortolotti, Yves; Cope, Florence; Stil, Irvin; Lefranc, Bastien; Garnier, Olivier; Butin, Gilles; Mattiocco, François; Navarro, Santiago; John, Dave; Navarrini, Alessandro; Schuster, Karl F.

    2012-09-01

    A 3mm band focal plane array heterodyne receiver is being developed for Nasmyth focus of the IRAM 30-m Pico Veleta Radio Telescope located in the Sierra Nevada Mountains, south of Spain. This receiver will comprise 25 dual linear polarization pixels operating across the 80-116GHz nominal band. Design efforts are being made to enlarge the band to cover the full 3mm atmospheric transmission window available at Pico Veleta, i.e. 72-116GHz. The instrument will be coupled to the Pico Veleta Telescope via a purely reflective low-loss optical system that includes a de-rotator. The receiver will be based on 5 x 5 cryogenically cooled dual-linear polarized feed horns cascaded with Ortho Mode Transducers (OMT) and side band separating SIS mixers, a technology which offers state-of-the-art performances for millimeter and sub-millimeter receivers.

  10. Pencil-like mm-size electron beams produced with linear inductive voltage adders (LIVA)

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Rovang, D.C. [and others

    1996-09-01

    This paper presents design, analysis, and first results of the high brightness electron beam experiments currently under investigation at Sandia. Anticipated beam parameters are: energy 12 MeV, current 35-40 kA, rms radius 0.5 mm, pulse duration 40 ns FWHM. The accelerator is SABRE, a pulsed LIVA modified to higher impedance, and the electron source is a magnetically immersed foilless electron diode. 20 to 30 Tesla solenoidal magnets are required to insulate the diode and contain the beam to its extremely small sized (1 mm) envelope. These experiments are designed to push the technology to produce the highest possible electron current in a submillimeter radius beam. Design, numercial simulations, and first experimental results are presented.

  11. Mohsen Akbari1 Ph.D. Candidate

    E-print Network

    Bahrami, Majid

    Mohsen Akbari1 Ph.D. Candidate Mechatronic System Engineering, School of Engineering Science, Simon Assistant Professor Mem. ASME Mechatronic System Engineering, School of Engineering Science, Simon Fraser Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8W 2Y2, Canada Majid Bahrami

  12. Instructor: Steven Wisensale, Ph.D.

    E-print Network

    Holsinger, Kent

    Instructor: Steven Wisensale, Ph.D. Professor of Public Policy-HDFS Topics Covered: · Origins 3042- African American Studies Baseball and Society: Politics, Economics, Race and Gender Baseball and Society: Politics, Economics, Race and GenderSpring 2012Spring 2012 New CourseNew Course For more

  13. Ph.D. PSYCHOLOGY Application Checklist

    E-print Network

    Northern British Columbia, University of

    Ph.D. PSYCHOLOGY Application Checklist IMPORTANT NOTES 1. Please submit all Application Materials.D. in Psychology must have both a Bachelors and Masters degree, at least one of which must be in Psychology (Maximum 10 pages). GRE Test Scores: Applicants who do not have a Master's degree in Psychology must submit

  14. Optoelectronic pH Meter: Further Details

    NASA Technical Reports Server (NTRS)

    Jeevarajan, Antony S.; Anderson, Mejody M.; Macatangay, Ariel V.

    2009-01-01

    A collection of documents provides further detailed information about an optoelectronic instrument that measures the pH of an aqueous cell-culture medium to within 0.1 unit in the range from 6.5 to 7.5. The instrument at an earlier stage of development was reported in Optoelectronic Instrument Monitors pH in a Culture Medium (MSC-23107), NASA Tech Briefs, Vol. 28, No. 9 (September 2004), page 4a. To recapitulate: The instrument includes a quartz cuvette through which the medium flows as it is circulated through a bioreactor. The medium contains some phenol red, which is an organic pH-indicator dye. The cuvette sits between a light source and a photodetector. [The light source in the earlier version comprised red (625 nm) and green (558 nm) light-emitting diodes (LEDs); the light source in the present version comprises a single green- (560 nm)-or-red (623 nm) LED.] The red and green are repeatedly flashed in alternation. The responses of the photodiode to the green and red are processed electronically to obtain the ratio between the amounts of green and red light transmitted through the medium. The optical absorbance of the phenol red in the green light varies as a known function of pH. Hence, the pH of the medium can be calculated from the aforesaid ratio.

  15. Ph.D. Thesis Frantz Brstrup

    E-print Network

    Ph.D. Thesis by Frantz Bræstrup Roskilde University, Department of Chemistry and Life Sciences of Denmark, Fuel Cells and Solid State Chemistry Division. June 2009 New Methods for Removal of Pollutants from Exhaust Gases #12;#12;Resum´e Forskellige typer af oxider med spinelstruktur er blevet undersøgt

  16. Darlene Ketten, Ph.D. Misconceptions

    E-print Network

    :FionaWatson/Survival Darlene Ketten s the world's foremost expert on marine mammal ears, Darlene R. Ketten, Ph.D. and Senior biomedical imaging, forensics and biophysical models of hearing in both humans and marine mammals. Her research focuses on two areas: how structural differences in marine vs. terrestrial mammal ears relate

  17. Scholarly Integrity Julie Simpson, Ph.D.

    E-print Network

    New Hampshire, University of

    Board site #12;Upcoming RCR Trainings New PhD student required training ~ Friday, September 27, 12 & scholarship Variable (2-3) credit Fulfills UNH doctoral and NSF RCR training requirements Tuesdays, 4 Public trust #12;Responsible Conduct of Research (RCR) & Scholarship Program Standing faculty committee

  18. 12 August 2001 quant-ph/0111069

    E-print Network

    Meyer, David A.

    12 August 2001 quant-ph/0111069 QUANTUM COMPUTING CLASSICAL PHYSICS David A. Meyer Project--quantum lattice gas automata--and show how to implement them efficiently on standard quantum computers. 2001 computing classical physics David A. Meyer 1. Introduction Quantum computing originated with Feynman

  19. AUTOMNE 2013 PhD EN COMMUNICATION

    E-print Network

    Parrott, Lael

    AUTOMNE 2013 PhD EN COMMUNICATION LUNDI MARDI MERCREDI JEUDI VENDREDI 9:00 � 12 Forum Doctoral Prof : Thierry Bardini Et Gaby Hsab UQAM Communication organisationnelle William Buxton (hors campus) Séminaire spécialisé : Médias mobiles et communication : approches

  20. PhD studentship: Population genomics of

    E-print Network

    Uppsala Universitet

    the acidification of the World's oceans. In the 250 years since the onset of the industrial revolution, atmospheric pessimistic of IPCC model scenarios. How will life in the oceans adapt to this changing environment CO2 levels have risen from 280 to 381 parts per million and average ocean pH has fallen from 8

  1. What My Ph.D. Taught Me

    ERIC Educational Resources Information Center

    Levenstein, Jessica

    2013-01-01

    The author started in the Ph.D. program in comparative literature at Princeton in 1992, a year after she graduated from college. She fell in love with mythology and the classical traditions and find herself teaching literature. In the remainder of her time at Princeton, she precepted for four or five more classes, got the chance to join the…

  2. Monitoring fetal pH by telemetry

    NASA Technical Reports Server (NTRS)

    Blum, A.; Donahoe, T.; Jhabvala, M. D.; Ryan, W.

    1980-01-01

    Telemetry unit has been developed for possible use in measuring scalp-tissue pH and heart rate of unborn infant. Unit radius data to receiver as much as 50 ft. away. Application exists during hours just prior to childbirth to give warning of problems that might require cesarean delivery.

  3. Curriculum Vitae GUOFAN SHAO, Ph.D.

    E-print Network

    Sinica (China), Journal of Forestry Research (China), Forestry ­ International Journal of Forest Research1 Curriculum Vitae GUOFAN SHAO, Ph.D. 1. Current Employment and Posts Professor, Purdue University-1989, Chinese Academy of Sciences. Supervised jointly Prof. Z. Wang. Partial research was accomplished

  4. Teaching Physics Using PhET Simulations

    ERIC Educational Resources Information Center

    Wieman, C. E.; Adams, W. K.; Loeblein, P.; Perkins, K. K.

    2010-01-01

    PhET Interactive Simulations (sims) are now being widely used in teaching physics and chemistry. Sims can be used in many different educational settings, including lecture, individual or small group inquiry activities, homework, and lab. Here we will highlight a few ways to use them in teaching, based on our research and experiences using them in…

  5. Ph.D. Assessment Form Student Name

    E-print Network

    Ph.D. Assessment Form Student Name: Major Advisor: Date: Outcome 1: Graduates will be able of cognitive and academic skills through their ability to recall and integrate knowledge from their specialty, including both written and oral parts, which assesses the student's breadth of knowledge in their discipline

  6. PH-315 A. La Rosa TRANSISTORS and

    E-print Network

    PH-315 A. La Rosa TRANSISTORS and TRANSISTOR AMPLIFIERS I. PURPOSE To familiarize with the characteristics of transistors, how to properly implement its DC bias, and illustrate its application as small signal amplifiers. The bipolar junction transistor as well as the field effect transistor

  7. Quasi-distributed pH sensor

    NASA Astrophysics Data System (ADS)

    Elliott, Nicholas J.; Wallace, Peter A.; Uttamlal, Mahesh; Smith, Sheila; Campbell, Michael

    1999-12-01

    A Quasi-distributed pH sensing system based on Optical Time Domain Reflectometry (OTDR) was developed to determine the spatial and intensity information from fluorescence signals coupled back into a single fiber. The evanescent wave due to a 488 nm light pulse from a N2 pumped dye laser was used to excite a pH sensitive fluorophore and the emission around 515 nm was detected. A 3dB Y-coupler was used to convey excitation light to the sensing sites and to deliver emission signals from these sites back to a filtered photomultiplier tube. Data collection was performed using a HP 54540A 500 MHz digital scope and analysis was carried out using a dedicated Pentium 166 MHz PC. A reproducible laboratory fabrication process was developed to produce sensing sites at discrete intervals along the length of the fiber. A polishing process carefully removed the cladding at each sensing site and photo- polymerization was then used to covalently bind the fluorophore fluorescein with a co-polymer directly onto the site. The results show the sensors performance over a range of pH4-pH10 with a pKa value of 6.3. The present system was chosen to have sites 10 m apart, however, based on the propagation rate of 5 ns m-1 for light in the fiber and 10 ns for the fluorescence lifetime, a resolution of approximately 1 m is possible.

  8. Curriculum vitae RAJINI RAO, Ph.D.

    E-print Network

    Rao, Rajini

    1 Curriculum vitae RAJINI RAO, Ph.D. 12 November, 2011 DEMOGRAPHIC INFORMATION CURRENT APPOINTMENT PEER-REVIEWED PUBLICATIONS 1. Holzschu, D., Principio, L., Conklin, K.T., Hickey, D.R., Short, S., Rao, 7125-7131 2. Rao, R., Perlin, D.S., and Senior, A.E. (1987) The defective proton-ATPase of uncA mutants

  9. Bose Einstein condensation in a mm-scale Ioffe Pritchard trap

    Microsoft Academic Search

    K. L. Moore; T. P. Purdy; K. W. Murch; K. R. Brown; K. Dani; S. Gupta; D. M. Stamper-Kurn

    2006-01-01

    We have constructed a mm-scale Ioffe Pritchard trap capable of providing axial field curvature of 7800 G\\/cm2 with only 10.5 A of driving current. Our novel fabrication method involving electromagnetic coils formed of anodized aluminum strips is compatible with ultra-high vacuum conditions, as demonstrated by our using the trap to produce Bose Einstein condensates of 106 87Rb atoms. The strong

  10. Two-phase heat transfer to a refrigerant in a 1 mm diameter tube

    Microsoft Academic Search

    S Lin; P. A Kew; K Cornwell

    2001-01-01

    A study of two-phase flow and heat transfer in a small tube of 1 mm internal diameter has been conducted experimentally as part of a wider study of boiling in small channels. R141b has been used as the working fluid. The boiling heat transfer in the small tube has been measured over a mass flux range of 300–2000 kg\\/m2 s

  11. Establishment and application of flow stress models of Mg-Y-MM-Zr alloy

    Microsoft Academic Search

    Ming-long MA; Xing-gang LI; Yong-jun LI; Lan-qiang HE; Kui ZHANG; Xian-wen WANG; Li-fang CHEN

    2011-01-01

    The hot working behaviors of Mg-9Y-1MM-0.6Zr (WE91) magnesium alloy were researched in a temperature range of 653-773 K and strain rate range of 0.001-1 s?1 on Gleeble-1500D hot simulator under the maximum deformation degree of 60%. A mathematical model was established to predict the stress-strain curves of this alloy during deformation. The experimental results show that the relationship between stress

  12. Lithium carbonate 24-hour extended-release capsule filled with 6 mm tablets.

    PubMed

    Pietkiewicz, P; Sznitowska, M; Dorosz, A; Lukasiak, J

    2003-01-01

    A 24-h extended-release multiparticulate capsule containing a dose of 500 mg of lithium carbonate divided into 6 tablets 6 mm in size was produced. In order to achieve an immediate and prolonged drug release profile one uncoated tablet and 5 tablets coated with methacrylic acid/ethyl acrylate copolymer Kollicoat MAE30DP were filled into a capsule. The core of tablets consisted of microcrystalline cellulose, lactose, povidone, macrogol and magnesium stearate. PMID:12705093

  13. AzTEC 1.1 mm OBSERVATIONS OF THE MBM12 MOLECULAR CLOUD

    SciTech Connect

    Kim, M. J.; Kim, S.; Youn, S.; Kang, Y.-W. [Department of Astronomy and Space Science, Sejong University, KwangJin-gu, KunJa-dong 98, Seoul 143-747 (Korea, Republic of); Yun, M. S.; Wilson, G. W. [Department of Astronomy, University of Massachusetts, 710 North Pleasant St., Amherst, MA 01003 (United States); Aretxaga, I.; Hughes, D. H.; Humphrey, A. [Instituto Nacional de Astrofisca, Optica y Electronica, Tonantzintla, Puebla (Mexico); Williams, J. P. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Austermann, J. E. [Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, Colorado 80309 (United States); Perera, T. A. [Department of Physics, Illinois Wesleyan University, Bloomington, IL 61701 (United States); Mauskopf, P. D. [School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom); Magnani, L., E-mail: sek@sejong.ac.kr [Department of Physics and Astronomy, The University of Georgia, Athens, GA 30602-2451 (United States)

    2012-02-10

    We present 1.1 mm observations of the dust continuum emission from the MBM12 high-latitude molecular cloud observed with the Astronomical Thermal Emission Camera (AzTEC) mounted on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. We surveyed 6.34 deg{sup 2} centered on MBM12, making this the largest area that has ever been surveyed in this region with submillimeter and millimeter telescopes. Eight secure individual sources were detected with a signal-to-noise ratio of over 4.4. These eight AzTEC sources can be considered to be real astronomical objects compared to the other candidates based on calculations of the false detection rate. The distribution of the detected 1.1 mm sources or compact 1.1 mm peaks is spatially anti-correlated with that of the 100 {mu}m emission and the {sup 12}CO emission. We detected the 1.1 mm dust continuum emitting sources associated with two classical T Tauri stars, LkH{alpha}262 and LkH{alpha}264. Observations of spectral energy distributions (SEDs) indicate that LkH{alpha}262 is likely to be Class II (pre-main-sequence star), but there are also indications that it could be a late Class I (protostar). A flared disk and a bipolar cavity in the models of Class I sources lead to more complicated SEDs. From the present AzTEC observations of the MBM12 region, it appears that other sources detected with AzTEC are likely to be extragalactic and located behind MBM12. Some of these have radio counterparts and their star formation rates are derived from a fit of the SEDs to the photometric evolution of galaxies in which the effects of a dusty interstellar medium have been included.

  14. 1. West portal of Tunnel 36, view to northeast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of Tunnel 36, view to northeast, 135mm lens. Note the notched wingwalls that originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 36, Milepost 176.92, Yuba Pass, Nevada County, CA

  15. In vivo regeneration of small-diameter (2 mm) arteries using a polymer scaffold

    Microsoft Academic Search

    Sandro Lepidi; Giovanni Abatangelo; Vincenzo Vindigni; Giovanni Paolo Deriu; Barbara Zavan; Carolin Tonello; Roberta Cortivo

    2005-01-01

    The difficulty of obtaining significant long-term patency and good wall mechanical strength in vivo has been a significant obstacle in achieving small-diameter vascular prostheses. The aim of the present study was to develop a prosthetic graft that could perform as a small-diameter vascular conduit. Tubular structures of hyaluronan (HYAFF-11 tubules, 2 mm diameter, 1 cm length) were grafted in the

  16. 30-W\\/mm GaN HEMTs by field plate optimization

    Microsoft Academic Search

    Y.-F. Wu; A. Saxler; M. Moore; R. P. Smith; S. Sheppard; P. M. Chavarkar; T. Wisleder; U. K. Mishra; P. Parikh

    2004-01-01

    GaN high-electron-mobility-transistors (HEMTs) on SiC were fabricated with field plates of various dimensions for optimum performance. Great enhancement in radio frequency (RF) current-voltage swings was achieved with acceptable compromise in gain, through both reduction in the trapping effect and increase in breakdown voltages. When biased at 120 V, a continuous wave output power density of 32.2 W\\/mm and power-added efficiency

  17. 10-W\\/mm AlGaN-GaN HFET with a field modulating plate

    Microsoft Academic Search

    Y. Ando; Y. Okamoto; H. Miyamoto; T. Nakayama; T. Inoue; M. Kuzuhara

    2003-01-01

    AlGaN-GaN heterojunction field-effect transistors (HFETs) with a field modulating plate (FP) were fabricated on an SiC substrate. The gate-drain breakdown voltage (BVgd) was significantly improved by employing an FP electrode, and the highest BVgd of 160 V was obtained with an FP length (LFP) of 1 ?m. The maximum drain current achieved was 750 mA\\/mm, together with negligibly small current

  18. M&M: A Passive Toolkit for Measuring, Tracking, and Correlating Path Characteristics

    Microsoft Academic Search

    Sachin Katti; Dina Katabi; Chuck Blake; Eddie Kohler; Jacob Strauss

    This paper presents M&M, a passive measurement toolkit suitable for large-scale studies of Internet path characteristics. ThemultiQ tool uses equally-spaced mode gaps in TCP flows' packet interarrival time distributions to detect multiple bottle- neck capacities and their relative order. Unlike other passive tools, multiQ can discover up to three bottlenecks from the trace of a single flow, and can work

  19. MM radio telescope with focal plane array for 3 K SSF search

    Microsoft Academic Search

    V. Khaikin; V. Dubrovich

    2004-01-01

    Spectral Spatial Fluctuations (SSF) of CMBR temperature must be a result of interaction of primordial molecules with CMBR and protoobjects moving with peculiar velocities relative to CMBR. Expected values of ?T\\/T ?10-5-10-6 and bandwidth of the lines is 0.1-3% depending on the scale of protoobjects and red shifts. It is proposed to use 2 m mm radio telescope of Tuorla

  20. Components and mechanical considerations for magnetic sound on 35mm film

    Microsoft Academic Search

    J. Frayne

    1954-01-01

    The art of sound recording in the motion picture field had reached a high professional status before magnetic recording began to receive consideration bythe radio and television industries. This articIe reviews this status and discusses the relative merits of 35-mm sprocket-hole film and inch tape with respect to the requirements of the motion picture industry. The article traces the applications