Small angle Ar2+ + Ar collisions

International Nuclear Information System (INIS)

Stevens, J.J.

1983-01-01

Electron capture in Ar 2+ + Ar is studied at low keV energies. Using Ar 2+ + He collisions as a calibration, it is shown that the dominant single electron capture process is endothermic and of the type Ar 2+ ( 3 P) + Ar → Ar + ( 2 P) + Ar + (3s 2 3p 4 nI), with nI primarily being 3d and 4p. Weaker exothermic processes are also found and are due mainly to the existence of long-lived highly-excited states in the incident Ar 2+ beam. The direct scattering and double electron capture processes are also studied. Direct scattering occurs with no target excitation. Differential cross sections are presented for the collision processes. The single electron capture results are interpreted using a simple model in which a strongly attractive intermediate state couples with incident and outgoing channels

Influence of Ar addition on ozone generation in nonthermal plasmas

International Nuclear Information System (INIS)

Chen, Hsin Liang; Lee, How Ming; Chen, Shiaw Huei; Wei, Ta Chin; Chang, Moo Been

2010-01-01

Inconsistency regarding the influence of Ar addition on ozone generation in a corona discharge has been found in relevant studies. Unlike in the literature to date, a dielectric barrier discharge (DBD) reactor is adopted in this study. In addition to clarifying whether using Ar as an additive would lead to different types of behavior in a DBD and a corona discharge, this study is also motivated to explore the possible causes leading to the inconsistency. The experimental results show that adding Ar into the O 2 plasma would lead to the same influence on ozone generation in the DBD and corona discharge. Moreover, all types of controversial behavior caused by Ar addition reported in the relevant literature are observed in this study as well, indicating that the results of this study are comprehensive enough to interpret the inconsistency. By examining the experimental results in detail, it is found that the controversial influences of Ar addition on ozone generation were found using different assumptions. At a fixed applied voltage, the ozone generation might increase as the Ar concentration is increased, which results from a higher discharge power. Nevertheless, for a certain specific input energy (the ratio of discharge power to gas flow rate), the ozone concentration is lower as the Ar concentration is increased. Therefore, adding Ar is not a good way to enhance ozone generation from an economic point of view.

40Ar/39Ar laser-probe dating of diamond inclusions from the Premier kimberlite

International Nuclear Information System (INIS)

Phillips, D.; Onstott, T.C.; Harris, J.W.; Strathclyde Univ., Glasgow

1989-01-01

Inclusions encapsulated by diamonds at the time of their formation provide a means for determining diamond crystallization ages and the chemistry of the surrounding upper mantle at that time. Sm-Nd studies of peridotitic inclusions, from Cretaceous-age kimberlites in southern Africa, suggest that the diamonds formed 3.3 Gyr ago. By contrast, eclogite-suite inclusions generally yield younger ages, sometimes approaching the time of kimberlite eruption. Here we report the results of 40 Ar/ 39 Ar laser-probe analyses of individual eclogitic clinopyroxene inclusions from Premier diamonds, which yield a mean age of 1,198±14 Myr. This age agrees well with Sm-Nd and 40 Ar/ 39 Ar analyses on similar Premier inclusions, and is indistinguishable from the inferred time of emplacement of the host kimberlite (1,150-1,230 Myr), which implies that diamond formation was essentially synchronous with kimberlite generation. The extrapolated non-radiogenic 40 Ar/ 36 Ar ratio of 334±102 is similar to the present-day atmospheric composition. This value is inconsistent with Sr and Nd isotopic signatures from Premier eclogite inclusions, which suggest a depleted mantle source ( 40 Ar/ 36 Ar>20,000). Pre-entrapment equilibration of the inclusions with an 36 Ar-rich fluid is the most probable explanation for the low non-radiogenic ( 40 Ar/ 36 Ar) composition. (author)

K/Ar hornblende ages from the higher Himalaya: implications for India-Asia collision and Himalayan metamorphosis

International Nuclear Information System (INIS)

Sorkhabi, R.B.; Stump, A.K.; Jain, A.K.; Manickavasagam, R.M.; Nishimura Susumu

1993-01-01

Two amphibolite samples from the Higher Himalayan Crystalline (HHC) belt from the Suru Valley, Zanskar, have yielded Eocene K/Ar hornblende cooling ages between 40 and 45 Ma, thus indicating much older peak metamorphic conditions in northern parts of the Indian Plate. These ages are in conformity with almost identical ages from metamorphic complexes across the Nanga Parbat syntaxis in Pakistan and reveal a 65 to 70-Ma collision phase of the Indian indentor in the NW-Himalaya. (author). 21 refs., 2 figs

Software Verification and Validation Report for the 244-AR Vault Interim Stabilization Ventilation System

International Nuclear Information System (INIS)

YEH, T.

2002-01-01

This document reports on the analysis, testing and conclusions of the software verification and validation for the 244-AR Vault Interim Stabilization ventilation system. Automation control system will use the Allen-Bradley software tools for programming and programmable logic controller (PLC) configuration. The 244-AR Interim Stabilization Ventilation System will be used to control the release of radioactive particles to the environment in the containment tent, located inside the canyon of the 244-AR facility, and to assist the waste stabilization efforts. The HVAC equipment, ducts, instruments, PLC hardware, the ladder logic executable software (documented code), and message display terminal are considered part of the temporary ventilation system. The system consists of a supply air skid, temporary ductwork (to distribute airflow), and two skid-mounted, 500-cfm exhausters connected to the east filter building and the vessel vent system. The Interim Stabilization Ventilation System is a temporary, portable ventilation system consisting of supply side and exhaust side. Air is supplied to the containment tent from an air supply skid. This skid contains a constant speed fan, a pre-filter, an electric heating coil, a cooling coil, and a constant flow device (CFD). The CFD uses a passive component that allows a constant flow of air to pass through the device. Air is drawn out of the containment tent, cells, and tanks by two 500-cfm exhauster skids running in parallel. These skids are equipped with fans, filters, stack, stack monitoring instrumentation, and a PLC for control. The 500CFM exhaust skids were fabricated and tested previously for saltwell pumping activities. The objective of the temporary ventilation system is to maintain a higher pressure to the containment tent, relative to the canyon and cell areas, to prevent contaminants from reaching the containment tent

Identification of excess 40Ar by the 40Ar/39Ar age spectrum technique

International Nuclear Information System (INIS)

Lanphere, M.A.; Dalrymple, G.B.

1976-01-01

40 Ar/ 39 Ar incremental heating experiments on igneous plagioclase, biotite, and pyroxene that contain known amounts of excess 40 Ar indicate that saddle-shaped age spectra are diagnostic of excess 40 Ar in igneous minerals as well as in igneous rocks. The minima in the age spectra approach but do not reach the crystallization age. Neither the age spectrum diagram nor the 40 Ar/ 36 Ar versus 39 Ar/ 36 Ar isochron diagram reliably reveal the crystallization age in such samples. (Auth.)

A Refined Astronomically Calibrated 40Ar/39Ar Age for Fish Canyon Sanidine

DEFF Research Database (Denmark)

Rivera, Tiffany; Storey, Michael; Zeeden, Christian

2011-01-01

Intercalibration between the astronomical and radio-isotopic dating methods provides a means to improving accuracy and reducing uncertainty of an integrated, multi-chronometer geologic timescale. Here we report a high-precision 40Ar/39Ar age for the Fish Canyon sanidine (FCs) neutron fluence...... sanidine age of 0.7674±0.0022 Ma (2σ, external errors) is indistinguishable from the ID-TIMS U/Pb zircon age (0.7671±0.0019 Ma). The consistency between the astronomically calibrated 40Ar/39Ar sanidine age and U/Pb zircon age for this Quaternary unit suggests that agreement between these two radio-isotopic...... dating techniques is now achievable at better than±0.3% (2σ) in the youngest part of geologic time (

Age intercalibration of 40Ar/39Ar sanidine and chemically distinct U/Pb zircon populations from the Alder Creek Rhyolite Quaternary geochronology standard

DEFF Research Database (Denmark)

Rivera, Tiffany; Storey, Michael; Schmitz, M. D.

2013-01-01

, and have less pronounced positive Ce and negative Eu anomalies, lower incompatible trace element contents, higher TiZR temperatures that range up to 840 °C, and significantly younger dates. The youngest Group A dates yield a weighted mean of 1.1978 ± 0.0046 Ma (2σ, including systematic uncertainties...... with the astronomical age estimate for the Cobb Mountain subchron determined by correlating the oxygen isotope record of the giant piston core MD972143 to the La93(1,1) orbital solution. On the basis of independent radio-isotopic and orbital forcing results, we propose the refined age of 1.1850 ± 0.0016 Ma (2σ external......We report results from a 40Ar/39Ar sanidine and CA-TIMS 238U/206Pb zircon dating study of eruption and crystal residence timescales of the Alder Creek Rhyolite (ACR), California, extruded during the Cobb Mountain normal-polarity subchron (C1r.2n). A 40Ar/39Ar ACR sanidine date of 1.1850 ± 0.0016 Ma...

Spectroanalytical investigations on inductively coupled N2/Ar and Ar/Ar high frequency plasmas

International Nuclear Information System (INIS)

Malinowski, P.; Mazurkiewicz, M.; Nickel, H.

1981-03-01

In order to improve the detection limits of trace elements in corrosion products of metallic materials, the inductively coupled plasma excitation source (ICP) was applied for spectroscopic analysis. Besides optimizing the working conditions for the mentioned materials, the fundamental research clearing the excitation processes in ICP was carried out. Basicly, two plasma systems were investigated: the nitrogen cooled N 2 /Ar- and pure Ar/Ar-plasma. The computed detection limits for 8 chosen elements are between 0.1 and 50 μg ml -1 in both plasmas. The advantage of ion lines was clearly present; in N 2 /Ar-plasma it was larger than in Ar/Ar-plasma. The excitation temperatures measured with help of ArI, FeI and ZnI lines rise with increasing power and decreasing distance from the induction coil. The distribution of Zn excitation temperature in N 2 /Ar-plasma as well as the measured N + 2 rotational and CN vibrational temperatures indicate, that the toroidal structure of Ar/Ar-plasma is not analogue to the N 2 /Ar-plasma. The values of the various excitation temperatures (Ar, Fe, Zn) and the differences between the excitation, vibration, rotation and ionization temperatures (Tsub(i) > Tsub(n) = Tsub(vib) > Tsub(rot)) indicate an absence of thermal equilibrium in the concerned system. (orig.)

Kinetics of Ar isotopes during neutron irradiation: 39Ar loss from minerals as a source of error in 40Ar/39Ar dating

International Nuclear Information System (INIS)

Hess, J.C.; Lippolt, H.J.

1986-01-01

The loss of 39 Ar from minerals in the course of neutron activation for 40 Ar/ 39 Ar dating is studied by directly measuring the loss rates in vacuum-sealed ampoules. Biotite shows 39 Ar losses between 0.1% and 16%. These losses are predominantly due to diffusion processes from K-poor alteration-phase intergrowths in the biotites at the elevated temperatures during the irradiation. Estimates for the irradiation temperatures range from 150 0 to 180 0 C. Direct 39 Ar recoil loss from biotite seems to be minor compared to difussion loss of recoil-implanted 39 Ar. Precise 40 Ar/ 39 Ar dating of biotites therefore requires the measurement of the 39 Ar losses during irradiation. Glauconite loses not only neutron-induced Ar isotopes ( 39 Ar: 20-22%, 37 Ar: 17-19%) but also radiogenic 40 Ar(∼9%). Slight 39 Ar losses are also observed for light micas (0.2% and 0.35%), hornblendes (0.1%) and sanidines (200 and 700 ppm). 25 refs.; 4 figs.; 6 tabs

Ar + NO microwave plasmas for Escherichia coli sterilization

International Nuclear Information System (INIS)

Hueso, Jose L; Rico, Victor J; Cotrino, Jose; Gonzalez-Elipe, Agustin R; Frias, Jose E

2008-01-01

Ar + NO microwave discharges are used for sterilization and the results are compared with additional experiments with Ar, O 2 and N 2 -O 2 plasma mixtures. The NO * species produced in the Ar-NO mixtures remain up to long distances from the source, thus improving the sterilization efficiency of the process. E. coli individuals exposed to the Ar + NO plasma undergo morphological damage and cell lysis. Combined effects of etching (by O * and Ar * species) and UV radiation (from deactivation of NO * species) are responsible for the higher activity found for this plasma mixture. (fast track communication)

Influences of atom Ar on Ar at C60 + Ar at C60 collisions

International Nuclear Information System (INIS)

Zhao Qiang; Zhou Hongyu; Zhang Fengshou

2007-01-01

A semi-emperical molecular dynamics model was developed. The central collisions of C 60 + C 60 and Ar at C 60 + Ar at C 60 at the same incident energy were investigated within this model. The fullerene dimers could be formed by a self-assembly of C 60 fullerene, and the new fullerene structure like 'peanut' could be formed by a self-assembly of Ar at C 60 . It was found that atom Ar had a great effect on the collision of Ar at C 60 + Ar at C 60 . (authors)

Experimental system to measure excitation cross-sections by electron impact. Measurements for ArI and ArII

International Nuclear Information System (INIS)

Blanco, F.; Sanchez, J.A.; Aguilera, J.A.; Campos, J.

1989-01-01

An experimental set-up to measure excitation cross-section of atomic and molecular levels by electron impact based on the optical method is reported. We also present some measurements on the excitation cross-section for ArI 5p'(1/2)0 level, and for simultaneous ionization and excitation of Ar leading to ArII levels belonging to the 3p 4 4p and 3p 4 4d configurations. (Author)

Ar + NO microwave plasmas for Escherichia coli sterilization

Energy Technology Data Exchange (ETDEWEB)

Hueso, Jose L; Rico, Victor J; Cotrino, Jose; Gonzalez-Elipe, Agustin R [Instituto de Ciencia de Materiales de Sevilla, Centro Mixto CSIC-Universidad de Sevilla, Centro de Investigaciones Cientificas Isla de la Cartuja, Avda. Americo Vespucio 49, 41092 Sevilla (Spain); Frias, Jose E [Instituto de BioquImica Vegetal y FotosIntesis (IBVF-CSIC). Centro de Investigaciones CientIficas Isla de la Cartuja. Avda Americo Vespucio, 49, 41092 Sevilla (Spain)], E-mail: jhueso@icmse.csic.es

2008-05-07

Ar + NO microwave discharges are used for sterilization and the results are compared with additional experiments with Ar, O{sub 2} and N{sub 2}-O{sub 2} plasma mixtures. The NO{sup *} species produced in the Ar-NO mixtures remain up to long distances from the source, thus improving the sterilization efficiency of the process. E. coli individuals exposed to the Ar + NO plasma undergo morphological damage and cell lysis. Combined effects of etching (by O{sup *} and Ar{sup *} species) and UV radiation (from deactivation of NO{sup *} species) are responsible for the higher activity found for this plasma mixture. (fast track communication)

40Ar/39Ar and K-Ar age constraints on the timing of regional deformation, south coast of New South Wales, Lachlan Fold Belt: problems and implications

International Nuclear Information System (INIS)

Fergusson, C.L.; Phillips, D.

2001-01-01

Four slate samples from subduction complex rocks exposed on the south coast of New South Wales, south of Batemans Bay, were analysed by K-Ar and 40 Ar/ 39 Ar step-heating methods, One sample contains relatively abundant detrital muscovite flakes that are locally oblique to the regional cleavage in the rock, whereas the remaining samples appear to contain sparse detrital muscovite. Separates of detrital muscovite yielded plateau ages of 505 + 3 Ma and 513 + 3 Ma indicating that inheritance has not been eliminated by metamorphism and recrystallisation. Step-heating analyses of whole-rock chips from all four slate samples produced discordant apparent age spectra with 'saddle shapes' following young apparent ages at the lowest temperature increments. Elevated apparent ages associated with the highest temperature steps are attributed to the presence of variable quantities of detrital muscovite ( 40 Ar/ 39 Ar integrated ages of ca 455Ma, which are some 15-30 million years older than K-Ar ages for the same samples. These discrepancies suggest that the slates have also been affected by recoil loss/redistribution of 39 Ar, Ieading to anomalously old 40 Ar/ 39 Ar ages. Two other samples, from slaty tectonic melange and intensely cleaved slate, yielded average 40 Ar/ 39 Ar integrated ages of ca 424Ma, which are closer to associated mean K-Ar ages of 423 + 4Ma and 409 + 16Ma, respectively. Taking into account the potential influences of recoil loss/redistribution of 39 Ar and inheritance, the results from the latter samples suggest a maximum age of ca 440 Ma for deformation/metamorphism. The current results indicate that recoil and inheritance problems may also have affected whole-rock 40 Ar/ 39 Ar data reported from other regions of the Lachlan Fold Belt. Therefore, until these effects are adequately quantified, models for the evolution of the Lachlan Fold Belt, that are based on such whole-rock 40 Ar/ 39 Ar data, should be treated with caution. Copyright (2001) Geological

Simultaneous measurement of the 37Ar and 39Ar activity

International Nuclear Information System (INIS)

Fisenko, A.V.

1978-01-01

A method for simultaneous measurement of 37 Ar and 39 Ar activities, based on the different radiation penetrabilities of these isotopes is described. Two versions are realized. In the first case, a two-section detector is used whose partition partially transmits 39 Ar β-radiation and fully absorbs 37 Ar Auger electrons. A mixture of 37 Ar and 39 Ar is introduced into an internal counter operating at anticoincidences with an external counter. In the second version, a scintillation detector is used as an external counter, while the 37 Ar- 39 Ar mixture is introduced into a gas counter with a thin cathode. The rated detection efficiency of 37 Ar radiation in both versions is 80%. When measurement duration is 500 h, the sensitivity is approximately 10 -14 and 6x10 -15 Ci for 39 Ar and 37 Ar respectively

Determination of Ar metastable atom densities in Ar and Ar/H2 inductively coupled low-temperature plasmas

International Nuclear Information System (INIS)

Fox-Lyon, N; Knoll, A J; Oehrlein, G S; Franek, J; Demidov, V; Koepke, M; Godyak, V

2013-01-01

Ar metastable atoms are important energy carriers and surface interacting species in low-temperature plasmas that are difficult to quantify. Ar metastable atom densities (N Ar,m ) in inductively coupled Ar and Ar/H 2 plasmas were obtained using a model combining electrical probe measurements of electron density (N e ) and temperature (T e ), with analysis of spectrally resolved Ar plasma optical emission based on 3p → 1s optical emission ratios of the 419.8 nm line to the 420.1 nm line. We present the variation of N Ar,m as the Ar pressure and the addition of H 2 to Ar are changed comparatively to recent adsorption spectroscopy measurements. (paper)

40Ar/39Ar geochronology of terrestrial pyroxene

Science.gov (United States)

Ware, Bryant; Jourdan, Fred

2018-06-01

Geochronological techniques such as U/Pb in zircon and baddeleyite and 40Ar/39Ar on a vast range of minerals, including sanidine, plagioclase, and biotite, provide means to date an array of different geologic processes. Many of these minerals, however, are not always present in a given rock, or can be altered by secondary processes (e.g. plagioclase in mafic rocks) limiting our ability to derive an isotopic age. Pyroxene is a primary rock forming mineral for both mafic and ultramafic rocks and is resistant to alteration process but attempts to date this phase with 40Ar/39Ar has been met with little success so far. In this study, we analyzed pyroxene crystals from two different Large Igneous Provinces using a multi-collector noble gas mass spectrometer (ARGUS VI) since those machines have been shown to significantly improve analytical precision compared to the previous single-collector instruments. We obtain geologically meaningful and relatively precise 40Ar/39Ar plateau ages ranging from 184.6 ± 3.9 to 182.4 ± 0.8 Ma (2σ uncertainties of ±1.8-0.4%) and 506.3 ± 3.4 Ma for Tasmanian and Kalkarindji dolerites, respectively. Those data are indistinguishable from new and/or published U-Pb and 40Ar/39Ar plagioclase ages showing that 40Ar/39Ar dating of pyroxene is a suitable geochronological tool. Scrutinizing the analytical results of the pyroxene analyses as well as comparing them to the analytical result from plagioclase of the same samples indicate pure pyroxene was dated. Numerical models of argon diffusion in plagioclase and pyroxene support these observations. However, we found that the viability of 40Ar/39Ar dating approach of pyroxene can be affected by irradiation-induced recoil redistribution between thin pyroxene exsolution lamellae and the main pyroxene crystal, hence requiring careful petrographic observations before analysis. Finally, diffusion modeling show that 40Ar/39Ar of pyroxene can be used as a powerful tool to date the formation age of mafic

40Ar/39Ar ages of adularia from the Golden Cross, Neavesville, and Komata epithermal deposits, Hauraki Goldfield, New Zealand

International Nuclear Information System (INIS)

Mauk, J.L.; Hall, C.M.

2004-01-01

New 40 Ar/ 39 Ar ages of adularia from three epithermal vein deposits in the Hauraki Goldfield constrain when these deposits formed. Adularia from veins at Neavesville has 40 Ar/ 39 Ar plateau and isochron ages of 6.89 ± 0.02 and 6.86 ± 0.02 Ma, respectively, similar to the 40 Ar/ 39 Ar plateau and isochron ages of adularia from veins at Golden Cross of 6.96 ± 0.04 and 6.93 ± 0.03 Ma, respectively. In contrast, Komata mineralisation formed at 5.99 ± 0.02 to 6.07 ± 0.03 Ma, based on the 40 Ar/ 39 Ar isochron and plateau ages of the adularia in these veins, similar to the previously reported 6.0 Ma age of mineralisation at Waihi/Favona. These preliminary data suggest that mineralisation in the Hauraki Goldfields occurred episodically. (author). 19 refs., 3 figs., 1 tab

Histone demethylase JMJD1A promotes alternative splicing of AR variant 7 (AR-V7) in prostate cancer cells.

Science.gov (United States)

Fan, Lingling; Zhang, Fengbo; Xu, Songhui; Cui, Xiaolu; Hussain, Arif; Fazli, Ladan; Gleave, Martin; Dong, Xuesen; Qi, Jianfei

2018-05-15

Formation of the androgen receptor splicing variant 7 (AR-V7) is one of the major mechanisms by which resistance of prostate cancer to androgen deprivation therapy occurs. The histone demethylase JMJD1A (Jumonji domain containing 1A) functions as a key coactivator for AR by epigenetic regulation of H3K9 methylation marks. Here, we describe a role for JMJD1A in AR-V7 expression. While JMJD1A knockdown had no effect on full-length AR (AR-FL), it reduced AR-V7 levels in prostate cancer cells. Reexpression of AR-V7 in the JMJD1A-knockdown cells elevated expression of select AR targets and partially rescued prostate cancer cell growth in vitro and in vivo. The AR-V7 protein level correlated positively with JMJD1A in a subset of human prostate cancer specimens. Mechanistically, we found that JMJD1A promoted alternative splicing of AR-V7 through heterogeneous nuclear ribonucleoprotein F (HNRNPF), a splicing factor known to regulate exon inclusion. Knockdown of JMJD1A or HNRNPF inhibited splicing of AR-V7, but not AR-FL, in a minigene reporter assay. JMJD1A was found to interact with and promote the recruitment of HNRNPF to a cryptic exon 3b on AR pre-mRNA for the generation of AR-V7. Taken together, the role of JMJD1A in AR-FL coactivation and AR-V7 alternative splicing highlights JMJD1A as a potentially promising target for prostate cancer therapy.

40Ar/39Ar studies of deep sea igneous rocks

International Nuclear Information System (INIS)

Seidemann, D.

1978-01-01

An attempt to date deep-sea igneous rocks reliably was made using the 40 Ar/ 39 Ar dating technique. It was determined that the 40 Ar/ 39 Ar incremental release technique could not be used to eliminate the effects of excess radiogenic 40 Ar in deep-sea basalts. Excess 40 Ar is released throughout the extraction temperature range and cannot be distinguished from 40 Ar generated by in situ 40 K decay. The problem of the reduction of K-Ar dates associated with sea water alteration of deep-sea igneous rocks could not be resolved using the 40 Ar/ 39 Ar technique. Irradiation induced 39 Ar loss and/or redistribution in fine-grained and altered igneous rocks results in age spectra that are artifacts of the experimental procedure and only partly reflect the geologic history of the sample. Therefore, caution must be used in attributing significance to age spectra of fine grained and altered deep-sea igneous rocks. Effects of 39 Ar recoil are not important for either medium-grained (or coarser) deep-sea rocks or glasses because only a small fraction of the 39 Ar recoils to channels of easy diffusion, such as intergranular boundaries or cracks, during the irradiation. (author)

Geological Dating by 40 Ar - 39 Ar method

International Nuclear Information System (INIS)

Vollbert Romero, M.E.

1992-01-01

The isotope 40 K is radioactive, it decays to 40 Ar stable. The number of 40 Ar atoms produced from 40 K, permits to calculate the date of rocks and minerals. This dating technique is named 'Conventional K-Ar Dating Method'. The 40 Ar - 39 Ar dating method permits to calculate the age of rocks and minerals eliminating the limitation of the K-Ar method by calculating potassium and argon concentrations in a single measurement of the ratio of argon isotopes. In this work, the irradiation of the sample with fast neutrons in the nuclear reactor was established. 39 Ar is obtained from the induced reaction 39 K (n,p) 39 Ar. Thus the ration of 40 Ar - 39 Ar allows to obtain the date of rocks and minerals. This ratio was measured in a mass spectrometer. If the measurement of argon concentration in the sample is carried out at different increasing temperature values, it is possible to get information of paleotemperatures. The number of atoms 39 Ar is a function of the number 39 K atoms, irradiation time, neutrons flux, its energy E and the capture cross section σ of 39 K. These parameters are calculate indirectly by obtaining the so called 'J value ' by using a standard mineral with known age (HD-BI y Biot-133), this mineral is irradiated together with the unknown age sample. The values of 'J' obtained are in the interval of 2.85 a 3.03 (x 10 - 3)J/h. Rocks from 'Tres Virgenes' were dated by the method described in this work, showing an agreement with previous values of different authors. The age of this rocks are from Cenozoico era, mainly in the miocene period. (Author)

Glycogen synthase kinase-3 inhibitors suppress the AR-V7-mediated transcription and selectively inhibit cell growth in AR-V7-positive prostate cancer cells.

Science.gov (United States)

Nakata, Daisuke; Koyama, Ryokichi; Nakayama, Kazuhide; Kitazawa, Satoshi; Watanabe, Tatsuya; Hara, Takahito

2017-06-01

Recent evidence suggests that androgen receptor (AR) splice variants, including AR-V7, play a pivotal role in resistance to androgen blockade in prostate cancer treatment. The development of new therapeutic agents that can suppress the transcriptional activities of AR splice variants has been anticipated as the next generation treatment of castration-resistant prostate cancer. High-throughput screening of AR-V7 signaling inhibitors was performed using an AR-V7 reporter system. The effects of a glycogen synthase kinase-3 (GSK3) inhibitor, LY-2090314, on endogenous AR-V7 signaling were evaluated in an AR-V7-positive cell line, JDCaP-hr, by quantitative reverse transcription polymerase chain reaction. The relationship between AR-V7 signaling and β-catenin signaling was assessed using RNA interference. The effect of LY-2090314 on cell growth in various prostate cancer cell lines was also evaluated. We identified GSK3 inhibitors as transcriptional suppressors of AR-V7 using a high-throughput screen with an AR-V7 reporter system. LY-2090314 suppressed the reporter activity and endogenous AR-V7 activity in JDCaP-hr cells. Because silencing of β-catenin partly rescued the suppression, it was evident that the suppression was mediated, at least partially, via the activation of β-catenin signaling. AR-V7 signaling and β-catenin signaling reciprocally regulate each other in JDCaP-hr cells, and therefore, GSK3 inhibition can repress AR-V7 transcriptional activity by accumulating intracellular β-catenin. Notably, LY-2090314 selectively inhibited the growth of AR-V7-positive prostate cancer cells in vitro. Our findings demonstrate the potential of GSK3 inhibitors in treating advanced prostate cancer driven by AR splice variants. In vivo evaluation of AR splice variant-positive prostate cancer models will help illustrate the overall significance of GSK3 inhibitors in treating prostate cancer. © 2017 Wiley Periodicals, Inc.

40Ar/39Ar laster fusion and K-Ar ages from Lathrop Wells, Nevada, and Cima, California: The age of the latest volcanic activity in the Yucca Mountain area

International Nuclear Information System (INIS)

Turrin, B.D.; Champion, D.E.

1991-01-01

K-Ar and 40 Ar/ 39 Ar ages from the Lathrop Wells volcanic center, Nevada, and from the Cima volcanic field, California, indicate that the recently reported 20-ka age estimate for the Lathrop Wells volcanic center is incorrect. Instead, an age of 119 ± 11 to 141 ± 10 ka is indicated for the Lathrop Wells volcanic center. This age corrected is concordant with the ages determined by two independent isotopic geochronometric techniques and with the stratigraphy of surficial deposits in the Yucca Mountain region. In addition, paleomagnetic data and radiometric age data indicate only two volcanic events at the Lathrop Wells volcanic center that are probably closely linked in time, not as many as five as recently reported. 32 refs., 2 figs., 2 tabs

AR coating with high damage threshold on SiO2 glass. Final report

International Nuclear Information System (INIS)

Toratani, H.; Kanamori, C.; Nakajima, S.; Nakagawa, K.; Izumitani, T.

1983-01-01

The following experimental results are shown: (1) uniformity of AR coatings on Optosil and Sprasil provided by LLNL; (2) relation between cleaning methods and properties of AR coatings; (3) baking and sintering conditions of gel-derived films; (4) heat treatment of AR coating in O 2 flow

Standardization of 40Ar-39Ar dating facility at KDMIPE, ONGC, Dehradun

International Nuclear Information System (INIS)

Rathore, S.S.; Singh, M.P.; Vijan, A.R.; Bansal, M.; Prabhu, B.N.; Misra, K.N.

2003-01-01

In the pursuit of acquiring state of the art technology, efforts were being made for last more than two years to establish 40 Ar- 39 Ar dating facility at KDMIPE. The 40 Ar- 39 Ar dating technique is an analytical conversion of the conventional K-Ar dating method. In this method, the sample to be dated is first irradiated in a nuclear reactor to transform a portion of 39 K to 39 Ar by the fast neutron reaction i.e. 39 K(n, p) 39 Ar. After irradiation, the sample is placed in an ultra-high vacuum system and the argon extracted from it by fusion is purified and analyzed isotopically in a mass spectrometer. The relative abundances of 40 Ar, 39 Ar, 37 Ar and 36 Ar are measured. The 40 Ar/ 39 Ar K is determined, where 40 Ar is the radiogenic argon, and 39 Ar K is the 39 Ar produced from 39 K during the irradiation. The 40 Ar/ 39 Ar K ratio is proportional to the 40 Ar/ 40 K ratio in the sample and, therefore, is proportional to age

Temperature and pressure effects on 40Ar-39Ar systematics

International Nuclear Information System (INIS)

Ozima, M.; Kaneoka, I.; Yanagisawa, M.

1979-01-01

The effects of thermal and compressional treatment on 40 Ar- 39 Ar systematics have been investigated on three artificially heated biotite samples (heated for 1 hour at 700 0 C and 860 0 C in air and 700 0 C in vacuum respectively) and uniaxially compressed granite (p=1400 bar) and basalt samples (p=1660 bar). The 40 Ar- 39 Ar results for the disturbed samples are compared with those for undisturbed samples. Except for the vacuum-heating case, the effects of the disturbances may be interpreted as the combined effect of a partial loss of radiogenic 40 Ar from the sample and an incorporation of air Ar into the sample. Common diagnostic effects are (1) reduction of the total fusion age, (2) distortion of the age spectrum and, if the degree of the partial Ar loss is small (3) approximate preservation of the isochron age, and (4) reduction of the intercept value ( 40 Ar/ 36 Ar) in the isochron plot. The features observed in the age spectra of artificially disturbed samples are rather common in geologically disturbed samples, suggesting that the artificial disturbances simulate the effects of geological disturbances on 40 Ar- 39 Ar systematics. (Auth.)

StAR protein and steroidogenic enzyme expressions in the rat Harderian gland.

Science.gov (United States)

Falvo, Sara; Chieffi Baccaria, Gabriella; Spaziano, Giuseppe; Rosati, Luigi; Venditti, Massimo; Di Fiore, Maria Maddalena; Santillo, Alessandra

2018-03-01

The Harderian gland (HG) of the rat (Rattus norvegicus) secretes copious amounts of lipids, such as cholesterol. Here we report a study of the expressions of the StAR protein and key steroidogenic enzymes in the HG of male and female rats. The objective of the present investigation was to ascertain (a) whether the rat HG is involved in steroid production starting with cholesterol, and (b) whether the pattern of gene and protein expressions together with the enzymatic activities display sexual dimorphism. The results demonstrate, for the first time, the expression of StAR gene and protein, and Cyp11a1, Hsd3b1, Hsd17b3, Srd5a1, Srd5a2 and Cyp19a1 genes in the rat HG. StAR mRNA and protein expressions were much greater in males than in females. Immunohistochemical analysis demonstrated a non-homogeneous StAR distribution among glandular cells. Hsd17b3 and Cyp19a1 mRNA levels were higher in males than in females, whereas Srd5a1 mRNA levels were higher in females than in males. No significant differences were observed in mRNA levels of Cyp11a1, Hsd3b1 and Srd5a2 between sexes. Furthermore, the in vitro experiments demonstrated a higher 5α-reductase activity in the female as compared to the male HG vice versa a higher P450 aro activity in males as compared to females. These results suggest that the Harderian gland can be classified as a steroidogenic tissue because it synthesizes cholesterol, expresses StAR and steroidogenic enzymes involved in both androgen and estrogen synthesis. The dimorphic expression and activity of the steroidogenic enzymes may suggest sex-specific hormonal effects into the HG physiology. Copyright © 2018 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Quantum treatment of the Ar-HI photodissociation dynamics

International Nuclear Information System (INIS)

Lopez-Lopez, Sergio; Prosmiti, Rita; Garcia-Vela, Alberto

2004-01-01

A wave packet simulation of the ultraviolet photolysis dynamics of Ar-HI(v=0) is reported. Cluster photodissociation is started from two different initial states, namely, the ground van der Waals (vdW) and the first excited vdW bending state, associated with the Ar-I-H and Ar-H-I isomeric forms of the system, respectively. Formation of Ar-I radical products is investigated over the energy range of the cluster absorption spectrum. It is found that the yield of bound Ar-I radical complexes is typically 90%-100% and 70%-80% for the initial states associated with the Ar-I-H and Ar-H-I isomers, respectively. This result is in agreement with the experimentally observed time-of-flight spectrum of the hydrogen fragment produced after Ar-HI photodissociation. The high Ar-I yield is explained mainly by the small amount of energy available for the radical that is converted into internal energy in the photofragmentation process, which enhances the Ar-I survival probability. Quantum interference effects manifest themselves in structures in the angular distribution of the hydrogen fragment, and in pronounced rainbow patterns in the rotational distributions of the Ar-I radical

Timing of Secondary Hydrothermal Alteration of the Luobusa Chromitites Constrained by Ar/Ar Dating of Chrome Chlorites

Directory of Open Access Journals (Sweden)

Wei Guo

2018-05-01

Full Text Available Chrome chlorites are usually found as secondary phases formed by hydrothermal alteration of chromite deposits and associated mafic/ultramafic rocks. Here, we report the 40Ar/39Ar age of chrome chlorites separated from the Luobusa massive chromitites which have undergone secondary alteration by CO2-rich hydrothermal fluids. The dating results reveal that the intermediate heating steps (from 4 to 10 of sample L7 generate an age plateau of 29.88 ± 0.42 Ma (MSWD = 0.12, plateau 39Ar = 74.6%, and the plateau data points define a concordant inverse isochron age of 30.15 ± 1.05 Ma (MSWD = 0.08, initial 40Ar/36Ar = 295.8 ± 9.7. The Ar release pattern shows no evidence of later degassing or inherited radiogenic component indicated by an atmospheric intercept, thus representing the age of the hydrothermal activity. Based on the agreement of this hydrothermal age with the ~30 Ma adakitic plutons exposed in nearby regions (the Zedong area, tens of kilometers west Luobusa and the extensive late Oligocene plutonism distributed along the southeastern Gangdese magmatic belt, it is suggested that the hydrothermal fluids are likely related to the ~30 Ma magmatism. The hydrothermal fluid circulation could be launched either by remote plutons (such as the Sangri granodiorite, the nearest ~30 Ma pluton west Luobusa or by a similar coeval pluton in the local Luobusa area (inferred, not found or reported so far. Our results provide important clues for when the listwanites in Luobusa were formed.

AR and TD Fossil Energy Materials Program. Quarterly progress report for the period ending December 31, 1981

Energy Technology Data Exchange (ETDEWEB)

1982-04-01

The ORNL Fossil Energy Materials Program Office compiles and issues this combined quarterly progress report from camera-ready copies submitted by each of the participating subcontractor organizations. This report of activities on the program is organized in accordance with a work breakdown structure defined in the AR and TD Fossil Energy Materials Program Plan for FY 1982-1986 in which projects are organized according to fossil energy technologies. This report is divided into parts and chapters with each part describing projects related to a particular fossil energy technology. Chapters within a part provide details of the various projects associated with that technology. We hope this series of AR and TD Fossil Energy Materials Program quarterly progress reports will aid in the dissemination of information developed on the program. Plans for the program will be issued annually. A draft of the program plan for FY 1982 to 1986 has been prepared and is in the review process. The implementation of these plans will be reflected by these quarterly progress reports, and this dissemination of information will bw augmented by topical or final reports as appropriate.

Incident reporting to BfArM - regulatory framework, results and challenges.

Science.gov (United States)

Seidel, Robin; Stößlein, Ekkehard; Lauer, Wolfgang

2016-04-01

Medical devices are manifold and one of the most innovative fields of technology. As technologies advance, former limits cease to exist and complex devices become reality. Medical devices represent a very dynamic field with high economic relevance. The manufacturer of a medical device is obliged to minimize product-related risks as well as to demonstrate compliance with the so-called "essential requirements" regarding safety and performance before placing the device on the market. Any critical incident in relation to the application of a medical device has to be reported to the competent authority for risk assessment, which in Germany is either the Federal Institute for Drugs and Medical Devices (BfArM) or the Paul Ehrlich Institute (PEI) depending on the type of device. In this article, the German regulatory framework for medical devices and the resulting tasks for BfArM are described as well as the topics of its recently installed research and development group on prospective risk identification and application safety for medical devices. Results of failure mode and root cause analyses of incident data are presented as well as further data on cases with the result "root-cause analysis not possible". Finally an outlook is given on future challenges regarding risk assessment for medical devices.

Laser-fusion 40Ar/39Ar Ages of Darwin Impact Glass

Science.gov (United States)

Lo, Ching-Hua; Howard, Kieren T.; Chung, Sun-Lin; Meffre, Sebastien

2002-11-01

Three samples of Darwin Glass, an impact glass found in Tasmania, Australia at the edge of the Australasian tektite strewn field were dated using the 40Ar/39Ar single-grain laser fusion technique, yielding isochron ages of 796-815 ka with an overall weighted mean of 816 ± 7 ka. These data are statistically indistinguishable from those recently reported for the Australasian tektites from Southeast Asia and Australia (761-816 ka; with a mean weighted age of 803 ± 3 ka). However, considering the compositional and textural differences and the disparity from the presumed impact crater area for Australasian tektites, Darwin Glass is more likely to have resulted from a distinct impact during the same period of time.

Reappraisal of Los Humeros Volcanic Complex by New U/Th Zircon and 40Ar/39Ar Dating: Implications for Greater Geothermal Potential

Science.gov (United States)

Carrasco-Núñez, G.; Bernal, J. P.; Dávila, P.; Jicha, B.; Giordano, G.; Hernández, J.

2018-01-01

Longevity and size of magmatic systems are fundamental factors for assessing the potential of a geothermal field. At Los Humeros volcanic complex (LHVC), the first caldera-forming event was reported at 460 ± 40 ka. New zircon U/Th and plagioclase 40Ar/39Ar dates of pre-, syn- and postcaldera volcanics allow a reappraisal of the evolution of the geothermally active LHVC. The age of the voluminous Xaltipan ignimbrite (115 km3 dense rock equivalent [DRE]) associated with the formation of the Los Humeros caldera is now constrained by two geochronometers (zircon U/Th and plagioclase 40Ar/39Ar dating) to 164 ± 4.2 ka, which postdates a long episode of precaldera volcanism (rhyolitic domes), the oldest age of which is 693.0 ± 1.9 ka (40Ar/39Ar). The inferred short residence time (around 5 ka) for the paroxysmal Xaltipan ignimbrite is indicative of rapid assembly of a large magma body and rejuvenation of the system due to recurrent recharge magmas, as it has been occurred in some other large magmatic systems. Younger ages than previously believed have been obtained also for the other voluminous explosive phases of the Faby fall tuff at ˜70 ka and the second caldera-forming Zaragoza ignimbrite with 15 km3 DRE, which erupted immediately after. Thus, the time interval that separates the two caldera-forming episodes at Los Humeros is only 94 kyr, which is a much shorter interval than suggested by previous K-Ar dates (410 kyr). This temporal proximity allows us to propose a caldera stage encompassing the Xaltipan and the Zaragoza ignimbrites, followed by emplacement at 44.8 ± 1.7 ka of rhyolitic magmas interpreted to represent a postcaldera, resurgent stage. Rhyolitic eruptions have also occurred during the Holocene (˜1,200 km3) and these new ages indicating much younger caldera-forming volcanism than previously believed are fundamental factors in the application of classical conductive models of heat resource, enhancing the heat production capacity and favor a higher

39Ar/Ar measurements using ultra-low background proportional counters

International Nuclear Information System (INIS)

Hall, Jeter; Aalseth, Craig E.; Bonicalzi, Ricco M.; Brandenberger, Jill M.; Day, Anthony R.; Humble, Paul H.; Mace, Emily K.; Panisko, Mark E.; Seifert, Allen

2016-01-01

Age-dating groundwater and seawater using the 39 Ar/Ar ratio is an important tool to understand water mass-flow rates and mean residence time. Low-background proportional counters developed at Pacific Northwest National Laboratory use mixtures of argon and methane as counting gas. We demonstrate sensitivity to 39 Ar by comparing geological (ancient) argon recovered from a carbon dioxide gas well and commercial argon. The demonstrated sensitivity to the 39 Ar/Ar ratio is sufficient to date water masses as old as 1000 years. - Highlights: • 39 Ar/Ar age dating is important for understanding environmental water migration. • Ultra low background proportional counters have been developed. • 39 Ar is detected in atmospheric argon at a rate of 70.3 counts per day. The demonstrated background is 166 counts per day. • Age dating is possible for water with underground residence time of up to 1000 years.

40Ar/39Ar age calibration against counted annuallayers

DEFF Research Database (Denmark)

Storey, Michael; Stecher, Ole

2008-01-01

The 40Ar/39Ar method, based on the decay of the naturally occurring radioactive isotope 40K, is capable of producing ages with precision better than ± 0.1 %. However, accuracy is limited to no better than 1 % mainly due to the relatively large uncertainty in the 40K decay constants. One approach...... worth exploring for an improved absolute age basis for the 40Ar/39Ar system is through cross-calibration with counted annual layers (e.g. tree rings, varves and ice cores). North Atlantic Ash Zone (NAAZ) II is found within the dated part of the annual Greenland ice core record. NAAZ II has been...... correlated to the Icelandic peralkaline rhyolitic Thorsmörk ignimbrite. We will present preliminary 40Ar/39Ar results on the age of this eruption...

A composite microdose Adaptive Response (AR) and Bystander Effect (BE) model-application to low LET and high LET AR and BE data.

Science.gov (United States)

Leonard, Bobby E

2008-08-01

It has been suggested that Adaptive Response (AR) may reduce risk of adverse health effects due to ionizing radiation. But very low dose Bystander Effects (BE) may impose dominant deleterious human risks. These conflicting behaviors have stimulated controversy regarding the Linear No-Threshold human risk model. A dose and dose rate-dependent microdose model, to examine AR behavior, was developed in prior work. In the prior work a number of in vitro and in vivo dose response data were examined with the model. Recent new data show AR behavior with some evidence of very low dose BE. The purpose of this work is to supplement the microdose model to encompass the Brenner and colleagues BaD (Bystander and Direct Damage) model and apply this composite model to obtain new knowledge regarding AR and BE and illustrate the use of the model to plan radio-biology experiments. The biophysical composite AR and BE Microdose Model quantifies the accumulation of hits (Poisson distributed, microdose specific energy depositions) to cell nucleus volumes. This new composite AR and BE model provides predictions of dose response at very low dose BE levels, higher dose AR levels and even higher dose Direct (linear-quadratic) Damage radiation levels. We find good fits of the model to both BE data from the Columbia University microbeam facility and combined AR and BE data for low Linear Energy Transfer (LET) and high LET data. A Bystander Factor of about 27,000 and an AR protection factor of 0.61 are obtained for the low LET in vivo mouse spleen exposures. A Bystander Factor of 317 and an AR protection factor of 0.53 are obtained for high LET radon alpha particles in human lymphocytes. In both cases the AR is activated at most by one or two radiation induced charged particle traversals through the cell nucleus. The results of the model analysis is consistent with a premise that both Bystander damage and Adaptive Response radioprotection can occur in the same cell type, derived from the same

40Ar/39Ar and K-Ar dating of altered glassy volcanic rocks: the Dabi Volcanics, P.N.G

International Nuclear Information System (INIS)

Walker, D.A.; McDougall, I.

1982-01-01

K-Ar and 40 Ar/ 39 Ar ages have been determined for altered submarine tholeiitic and boninite (high-Mg andesite) lavas from the Dabi Volcanics, Cape Vogel Peninsula, Papua New Guinea. 40 Ar/ 39 Ar whole rock total fusion and plateau ages identify a Late Paleocene age for the tholeiitic lavas (58.9 +- 1.1 Ma), and also for the boninitic lavas (58.8 +- 0.8 Ma). Apparent K-Ar ages for the same samples range from 27.2 +- 0.7 to 63.9 +- 4.5 Ma, and young K-Ar ages for glassy boninites are probably due to variable radiogenic 40 Ar( 40 Ar*) loss. These new ages effectively reconcile previously ambiguous age data for the Dabi Volcanics, and indicate contemporaneous tholeiitic and boninitic volcanism occurring in southeast PNG during the Late Paleocene. Smectites, developed as alteration products after glass in oceanic lavas commonly do not retain 39 Ar during or subsequent to irradiation, but in some cases may contain 40 Ar*. The results are discussed. (author)

40Ar-39Ar stepheating studies of clay concentrates from Irish orebodies

International Nuclear Information System (INIS)

Halliday, A.N.

1978-01-01

40 Ar- 39 Ar step heating analyses of clay concentrates from the Gortdrum and Tynagh orebodies (Ireland) previously dated by conventional K-Ar, indicate major losses of 39 Ar (32 to 45%) and rad. 40 Ar (25 to 35%) during the irradiation. The proportion of rad. 40 Ar loss, unlike that of 39 Ar, increases with J-value. The difference between 39 Ar and rad. 40 Ar proportion losses is related to the mineralogy and grain intimacy. These also affect the stepwise release patterns - the Gortdrum concentrates yield age spectra very consistent with 39 Ar recoil predictions, whereas the Tynagh concentrates in which the grains are intimately intergrown, show no clear evidence for 39 Ar recoil depletion in the K-rich phases. The difference is resolvable if illite argon release is not a simple volume diffusion type process under vacuum conditions. (author)

Study of the physical discharge properties of a Ar/O2 DC plasma jet

Science.gov (United States)

Barkhordari, A.; Ganjovi, A.; Mirzaei, I.; Falahat, A.

2018-03-01

In this paper, the physical properties of plasma discharge in a manufactured DC plasma jet operating with the Ar/O2 gaseous mixture are studied. Moreover, the optical emission spectroscopy technique is used to perform the experimental measurements. The obtained emission spectra are analyzed and, the plasma density, rotational, vibrational and electronic temperature are calculated. The NO emission lines from {NO }γ( A2 Σ^{+} \\to {X}2 Πr ) electronic transition are observed. It is seen that, at the higher argon contributions in Ar/O2 gaseous mixture, the emission intensities from argon ions will increase. Moreover, while the vibrational and excitation temperatures are increased at the higher input DC currents, they will decrease at the higher Ar percentages in the Ar/O2 gaseous mixture. Furthermore, at the higher DC currents and Ar contributions, both the plasma electron density and dissociation fraction of oxygen atoms are increased.

Pig StAR: mRNA expression and alternative splicing in testis and Leydig cells, and association analyses with testicular morphology traits.

Science.gov (United States)

Zhang, Yanghai; Cui, Yang; Zhang, Xuelian; Wang, Yimin; Gao, Jiayang; Yu, Ting; Lv, Xiaoyan; Pan, Chuanying

2018-05-31

Steroidogenic acute regulatory protein (StAR), primarily expressed in Leydig cells (LCs) in the mammalian testes, is essential for testosterone biosynthesis and male fertility. However, no previous reports have explored the expression profiles, alternative splicing and genetic variations of StAR gene in pig. The aim of current study was to explore the expression profiles in different tissues and different types of testicular cells (LCs; spermatogonial stem cells, SSCs; Sertoli cells, SCs), to identify different splice variants and their expression levels, as well as to detect the indel polymorphism in pig StAR gene. Expression analysis results revealed that StAR was widely expressed in all tested tissues and the expression level in testis was significantly higher than that in other tissues (P StAR mRNA expression level was significantly higher in LCs than others (P StAR-a, StAR-b and StAR-c, were first found in pig. Further study showed StAR-a was highly expressed in both testis and LCs when compared with other variants (P StAR-a was the primary variant at StAR gene post-transcription and may facilitate the combination and transportation of cholesterol with StAR. In addition, a 5-bp duplicated deletion (NC_010457.5:g.5524-5528 delACTTG) was verified in the porcine StAR gene, which was closely related to male testicular morphology traits (P StAR gene might be a positive allele. Briefly, the current findings suggest that StAR and StAR-a play imperative roles in male fertility and the 5-bp indel can be a potential DNA marker for the marker-assisted selection in boar. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of shock pressure on 40Ar-39Ar radiometric age determinations

International Nuclear Information System (INIS)

Davis, P.K.

1977-01-01

The relation of shock to the drop in the 40 *Ar/ 39 *Ar ratio seen at high release temperatures in some neutron-irradiated lunar samples is investigated through measurements of the 40 *Ar/ 39 *Ar ratio in gas samples released by stepwise heating of rock samples previously subjected to shock, either in the laboratory or in nature. Explosives were used to shock solid pieces and powder of a basalt from a diabase dike in Liberia to calculated pressures of 65, 150 and 270 kbar. These, an unshocked sample of the powder, two naturally shocked samples from the Brent impact crater in Canada, one unshocked sample from near the crater, and appropriate monitors were irradiated. Ar from stepwise heating was analyzed. The unshocked basalt shows a good 40 *Ar/ 39 *Ar plateau at age 198 +-9 m.y. in agreement with a previous result of 186 +- 2 m.y. The shocked samples contain varying amounts of implanted atmospheric Ar, the isotopes of which have experienced mass fractionation. This effect is small enough in four samples so that the linearity of their graphs of 39 *Ar/ 40 Ar vs 36 Ar/ 40 Ar is evidence of a plateau. The ages of these samples are then 201 +- 10, 205 +- 12 and 201 +-9 m.y. It appears that the shock has had little effect on the 40 Ar- 39 Ar age spectrum, although the release patterns of the 39 *Ar are shifted downward by the order of 200 0 C. Shock implantation of Ar was at lower shock pressure, in the presence of less Ar, and into a less porous material than previously demonstrated. The Brent Crater samples do not all show good plateaus, but do indicate an age of 420 m.y. for the crater event and 795 +- 24 m.y. for the rock formation, in agreement with previous results. None of the 40 *Ar/ 39 *Ar profiles shows a drop at high temperature, but a possible role of shock implantation of Ar is indicated in the production of this effect. Further experiments are suggested. (author)

Mass and velocity of fragments from the reaction 17-115 MeV/u 40Ar + Cu, Ag and Au

International Nuclear Information System (INIS)

Colin, E.; Guinet, D.; Stern, M.

1998-01-01

Measurements are reported for fragment masses and velocities from the reactions 17-115 MeV/u 40 Ar + Cu, Ag and Au. High momentum and energy deposition are reported for selected events, even for higher incident energy. Further study is needed to understand their origin. (authors)

Preparation and characterization of pulsed laser deposited CdTe thin films at higher FTO substrate temperature and in Ar + O{sub 2} atmosphere

Energy Technology Data Exchange (ETDEWEB)

Ding, Chao; Ming, Zhenxun [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Li, Bing, E-mail: libing70@126.com [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Feng, Lianghuan [College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan (China); Wu, Judy [Department of Physics and Astronomy, Kansas University, Lawrence 66045 (United States)

2013-06-20

Highlights: • CdTe films were deposited by PLD at high substrate temperatures (400 °C, 550 °C). • CdTe films were achieved under the atmosphere (1.2 Torr) of Ar mixed with O{sub 2}. • Deposited CdTe films were cubic phase and had strong (1 0 0) preferred orientation. • Scanning electron microscope (SEM) showed an average grain size of 0.3–0.6 μm. • The ultra-thin film (CdS/PLD-CdTe) solar cell with efficiency of 6.68% was made. -- Abstract: Pulsed laser deposition (PLD) is one of the promising techniques for depositing cadmium telluride (CdTe) thin films. It has been reported that PLD CdTe thin films were almost deposited at the lower substrate temperatures (<300 °C) under vacuum conditions. However, the poor crystallinity of CdTe films prepared in this way renders them not conducive to the preparation of high-efficiency CdTe solar cells. To obtain high-efficiency solar cell devices, better crystallinity and more suitable grain size are needed, which requires the CdTe layer to be deposited by PLD at high substrate temperatures (>400 °C). In this paper, CdTe layers were deposited by PLD (KrF, λ = 248 nm, 10 Hz) at different higher substrate temperatures (T{sub s}). Excellent performance of CdTe films was achieved at higher substrate temperatures (400 °C, 550 °C) under an atmosphere of Ar mixed with O{sub 2} (1.2 Torr). X-ray diffraction analysis confirmed the formation of CdTe cubic phase with a strong (1 0 0) preferential orientation at all substrates temperatures on 60 mJ laser energy. The optical properties of CdTe were investigated, and the band gaps of CdTe films were 1.51 eV and 1.49 eV at substrate temperatures of 400 °C and 550 °C, respectively. Scanning electron microscopy (SEM) showed an average grain size of 0.3–0.6 μm. Thus, under these conditions of the atmosphere of Ar + O{sub 2} (15 Torr) and at the relatively high T{sub s} (500 °C), an thin-film (FTO/PLD-CdS (100 nm)/PLD-CdTe (∼1.5 μm)/HgTe: Cu/Ag) solar cell with an

Electron scattering from 36Ar and 40Ar

International Nuclear Information System (INIS)

Finn, J.M.

1975-01-01

The argon isotopes, 36 Ar and 40 Ar, have been investigated using electron scattering at the high-resolution Linac facilities of the National Bureau of Standards. Both elastic scattering and scattering to low-lying states have been observed. A high-pressure, low-volume gas target cell was designed and developed for this experiment. The cell features a transmission geometry and has resolution comparable to solid targets. Spectra were obtained at incident beam energies ranging from 65 to 115 MeV at scattering angles of 92.5 0 and 110 0 . Values obtained for the rms charge radii are 3.327 +- 0.015 and 3.393 +- 0.015 fm for 36 Ar and 40 Ar respectively. A sensitive measurement was made of the difference in the two radii yielding a value of Δ r = 0.079 +- 0.006 fm. The inelastic levels observed are the 1.97 (2 + ) and 4.18 MeV (3 - ) levels in 36 Ar, and the 1.46 (2 + ), 2.52 (2 + ), 3.21 (2 + ), and 3.68 MeV (3 - ) levels in 40 Ar. A Tassie model analysis was made of the inelastic transitions in the DWBA approximation and transition strengths of these levels were extracted

244-AR vault cooling water stream-specific report

International Nuclear Information System (INIS)

1990-08-01

The proposed wastestream designation for the 244-AR Vault cooling water wastestream is that this stream is not a dangerous waste, pursuant to the Washington (State) Administration Code (WAC) 173-303, Dangerous Waste Regulations. A combination of process knowledge and sampling data was used to make this determination. 21 refs., 6 figs., 7 tabs

Baicalein suppresses the androgen receptor (AR)-mediated prostate cancer progression via inhibiting the AR N-C dimerization and AR-coactivators interaction.

Science.gov (United States)

Xu, Defeng; Chen, Qiulu; Liu, Yalin; Wen, Xingqiao

2017-12-01

Androgen receptor (AR) plays a critical role in prostate cancer (PCa) development and progression. Androgen deprivation therapy with antiandrogens to reduce androgen biosynthesis or prevent androgens from binding to AR are widely used to suppress AR-mediated PCa growth. However, most of ADT may eventually fail with development of the castration resistance after 12-24 months. Here we found that a natural product baicalein can effectively suppress the PCa progression via targeting the androgen-induced AR transactivation with little effect to AR protein expression. PCa cells including LNCaP, CWR22Rv1, C4-2, PC-3, and DU145, were treated with baicalein and luciferase assay was used to evaluate their effect on the AR transactivation. Cell growth and IC 50 were determined by MTT assay after 48 hrs treatment. RT-PCR was used to evaluate the mRNA levels of AR target genes including PSA, TMPRSS2, and TMEPA1. Western blot was used to determine AR and PSA protein expression. The natural product of baicalein can selectively inhibit AR transactivation with little effect on the other nuclear receptors, including ERα, and GR. At a low concentration, 2.5 μM of baicalein effectively suppresses the growth of AR-positive PCa cells, and has little effect on AR-negative PCa cells. Mechanism dissection suggest that baicalein can suppress AR target genes (PSA, TMPRSS2, and TMEPA1) expression in both androgen responsive LNCaP cells and castration resistant CWR22Rv1 cells, that may involve the inhibiting the AR N/C dimerization and AR-coactivators interaction. Baicalein may be developed as an effective anti-AR therapy via its ability to inhibit AR transactivation and AR-mediated PCa cell growth.

/sup 40/Ar//sup 39/Ar and K-Ar dating of altered glassy volcanic rocks: the Dabi Volcanics, P. N. G

Energy Technology Data Exchange (ETDEWEB)

Walker, D.A. (Australian National Univ., Canberra. Dept. of Geology); McDougall, I. (Australian National Univ., Canberra. Research School of Earth Sciences)

1982-11-01

K-Ar and /sup 40/Ar//sup 39/Ar ages have been determined for altered submarine tholeiitic and boninite (high-Mg andesite) lavas from the Dabi Volcanics, Cape Vogel Peninsula, Papua New Guinea. /sup 40/Ar//sup 39/Ar whole rock total fusion and plateau ages identify a Late Paleocene age for the tholeiitic lavas (58.9 +- 1.1 Ma), and also for the boninitic lavas (58.8 +- 0.8 Ma). Apparent K-Ar ages for the same samples range from 27.2 +- 0.7 to 63.9 +- 4.5 Ma, and young K-Ar ages for glassy boninites are probably due to variable radiogenic /sup 40/Ar(/sup 40/Ar*) loss. These new ages effectively reconcile previously ambiguous age data for the Dabi Volcanics, and indicate contemporaneous tholeiitic and boninitic volcanism occurring in southeast PNG during the Late Paleocene. Smectites, developed as alteration products after glass in oceanic lavas commonly do not retain /sup 39/Ar during or subsequent to irradiation, but in some cases may contain /sup 40/Ar*. The results are discussed.

Characteristics of violent collisions in Ar-induced reactions at intermediaire energies

International Nuclear Information System (INIS)

Rivet, M.F.; Borderie, B.

1984-01-01

We report on two experiments performed with the Ganil facility using the 27 MeV/u Ar beam. The first one concerns an intermediate mass system, Ar + Ag. For the second one a heavier fissile system, Ar + U, was chosen. For Ar + Ag information about fusion requires the measurements of evaporation residues and fission. In the Ar + U reaction, most of the collisions lead to fission. The violence of the collision is therefore determined from the correlation angle of the coincidence fission fragments

Characterization of a novel androgen receptor (AR) coregulator RIPK1 and related chemicals that suppress AR-mediated prostate cancer growth via peptide and chemical screening.

Science.gov (United States)

Hsu, Cheng-Lung; Liu, Jai-Shin; Lin, Ting-Wei; Chang, Ying-Hsu; Kuo, Yung-Chia; Lin, An-Chi; Ting, Huei-Ju; Pang, See-Tong; Lee, Li-Yu; Ma, Wen-Lung; Lin, Chun-Cheng; Wu, Wen-Guey

2017-09-19

Using bicalutamide-androgen receptor (AR) DNA binding domain-ligand binding domain as bait, we observed enrichment of FxxFY motif-containing peptides. Protein database searches revealed the presence of receptor-interacting protein kinase 1 (RIPK1) harboring one FxxFY motif. RIPK1 interacted directly with AR and suppressed AR transactivation in a dose-dependent manner. Domain mapping experiments showed that the FxxFY motif in RIPK1 is critical for interactions with AR and the death domain of RIPK1 plays a crucial role in its inhibitory effect on transactivation. In terms of tissue expression, RIPK1 levels were markedly higher in benign prostate hyperplasia and non-cancerous tissue regions relative to the tumor area. With the aid of computer modeling for screening of chemicals targeting activation function 2 (AF-2) of AR, we identified oxadiazole derivatives as good candidates and subsequently generated a small library of these compounds. A number of candidates could effectively suppress AR transactivation and AR-related functions in vitro and in vivo with tolerable toxicity via inhibiting AR-peptide, AR-coregulator and AR N-C interactions. Combination of these chemicals with antiandrogen had an additive suppressive effect on AR transcriptional activity. Our collective findings may pave the way in creating new strategies for the development and design of anti-AR drugs.

Single electron capture by state-prepared Ar2+ projectiles in Ar

International Nuclear Information System (INIS)

Puerta, J.; Huber, B.A.

1985-03-01

Electron capture by state-selected Ar 2+ projectiles in Ar has been studied at low collision energies ( 2+ ions are measured explaining existing discrepancies of partial and total cross sections in the Ar 2+ /Ar collision system. Although highly excited metastable ions ( 5 D 4 0 , 3 F 4 0 ) represent a minor contamination of a non-prepared Ar 2+ beam (proportional1%), their contributions are found to dominate the capture process due to cross section values larger than 10 -15 cm 2 . (orig.)

AR-Signaling in Human Malignancies: Prostate Cancer and Beyond

Directory of Open Access Journals (Sweden)

Michael T. Schweizer

2017-01-01

Full Text Available In the 1940s Charles Huggins reported remarkable palliative benefits following surgical castration in men with advanced prostate cancer, and since then the androgen receptor (AR has remained the main therapeutic target in this disease. Over the past couple of decades, our understanding of AR-signaling biology has dramatically improved, and it has become apparent that the AR can modulate a number of other well-described oncogenic signaling pathways. Not surprisingly, mounting preclinical and epidemiologic data now supports a role for AR-signaling in promoting the growth and progression of several cancers other than prostate, and early phase clinical trials have documented preliminary signs of efficacy when AR-signaling inhibitors are used in several of these malignancies. In this article, we provide an overview of the evidence supporting the use of AR-directed therapies in prostate as well as other cancers, with an emphasis on the rationale for targeting AR-signaling across tumor types.

On mechanism of Ar(3p54p) states excitation in low-energy Ar-Ar collisions

International Nuclear Information System (INIS)

Kurskov, S Y; Kashuba, A S

2009-01-01

The present work is devoted to study of Ar(3p 5 4p) states excitation in binary low-energy Ar-Ar collisions. The results of the experimental investigation of excitation cross sections of Ar I 4p'[l/2] 1 , 4p'[3/2] 1 , 4p'[3/2] 2 and 4p[3/2] 2 levels in the collision energy range from threshold up to 500 eV (cm) and degree of polarization for 4s[3/2] 2 0 -4p'[l/2] 1 and 4s[3/2] 2 0 -4p[3/2] 2 transitions in this energy range are represented.

First-principles calibration of 40Ar/39Ar mineral standards and complete extraction of 40Ar* from sanidine

Science.gov (United States)

Morgan, L. E.; Kuiper, K.; Mark, D.; Postma, O.; Villa, I. M.; Wijbrans, J. R.

2010-12-01

40Ar/39Ar geochronology relies on comparing argon isotopic data for unknowns to those for knowns. Mineral standards used as neutron fluence monitors must be dated by the K-Ar method (or at least referenced to a mineral of known K-Ar age). The commonly used age of 28.02 ± 0.28 Ma for the Fish Canyon sanidine (FCs) (Renne et al., 1998) is based upon measurements of radiogenic 40Ar in GA1550 biotite (McDougall and Roksandic, 1974), but underlying full data were not published (these measurements were never intended for use as an international standard), so uncertainties are difficult to assess. Recent developments by Kuiper et al. (2008) and Renne et al. (2010) are limited by their reliance on the accuracy of other systems. Modern technology should allow for more precise and accurate calibration of primary K-Ar and 40Ar/39Ar standards. From the ideal gas law, the number of moles of 40Ar in a system can be calculated from measurements of pressure, volume, and temperature. Thus we have designed and are proceeding to build a pipette system to introduce well-determined amounts of 40Ar into noble gas extraction lines and mass spectrometers. This system relies on components with calibrations traceable to SI unit prototypes, including a diaphragm pressure gauge (MKS Instruments), thermocouples, and a “slug” of an accurately determined volume to be inserted into the reservoir for volume determinations of the reservoir and pipette. The system will be renewable, with a lifetime of ca. 1 month for gas in the reservoir, and portable, to permit interlaboratory calibrations. The quantitative extraction of 40Ar* from the mineral standard is of highest importance; for sanidine standards this is complicated by high melt viscosity during heating. Experiments adding basaltic “zero age glass” (ZAG) to decrease melt viscosity are underway. This has previously been explored by McDowell (1983) with a resistance furnace, but has not been quantitatively addressed with laser heating

Comparative simulation analysis on the ignition threshold of atmospheric He and Ar dielectric barrier discharge

Science.gov (United States)

Yao, Congwei; Chang, Zhengshi; Chen, Sile; Ma, Hengchi; Mu, Haibao; Zhang, Guan-Jun

2017-09-01

Dielectric barrier discharge (DBD) is widely applied in many fields, and the discharge characteristics of insert gas have been the research focus for years. In this paper, fluid models of atmospheric Ar and He DBDs driven by 22 kHz sinusoidal voltage are built to analyze their ignition processes. The contributions of different electron sources in ignition process are analyzed, including the direct ionization of ground state atom, stepwise ionization of metastable particles, and secondary electron emission from dielectric wall, and they play different roles in different discharge stages. The Townsend direct ionization coefficient of He is higher than Ar with the same electrical field intensity, which is the direct reason for the different ignition thresholds between He and Ar. Further, the electron energy loss per free electron produced in Ar and He DBDs is discussed. It is found that the total electron energy loss rate of Ar is higher than He when the same electrical field is applied. The excitation reaction of Ar consumes the major electron energy but cannot produce free electrons effectively, which is the essential reason for the higher ignition threshold of Ar. The computation results of He and Ar extinction voltages can be explained in the view of electron energy loss, as well as the experimental results of different extinction voltages between Ar/NH3 and He DBDs.

Experimental Determination of the Cosmogenic Ar Production Rate From Ca

Science.gov (United States)

Niedermann, S.; Schäfer, J. M.; Wieler, R.; Naumann, R.

2005-12-01

Cosmogenic 38Ar is produced in terrestrial surface rocks by spallation of target nuclides, in particular K and Ca. Though the presence of cosmogenic Ar in Ca-rich minerals has been demonstrated earlier [1], is has proven difficult to establish its production rate. To circumvent problems connected to 36Ar production by 35Cl neutron capture and different production rates from K and Ca, we have analyzed the noble gases in seven pyroxene separates (px) from the Antarctic Dry Valleys which are essentially free of Cl and K. The px were obtained from dolerite rocks, for which 3He and 21Ne exposure ages from 1.5 to 6.5 Ma have been reported [2]. The noble gases were extracted in two or three heating steps at GFZ Potsdam, yielding 38Ar/36Ar ratios up to 0.2283 ± 0.0008 (air: 0.1880). Ca (3.7-11.2 wt. %) is expected to be the only relevant target element for Ar production in the five pure px (ratio of 1.5 ± 0.2, we obtain cosmogenic 38Ar concentrations between 130 and 530x106 atoms/g. The 38Ar production rate was calculated based on 21Ne exposure ages [2], corrected for elevated nuclide production in Antarctica due to prevailing low air pressure and for the revised 21Ne production rate from Si. We obtain values between 188 ± 17 and 243 +110/-24 atoms (g Ca)-1 a-1 at sea level and high (northern) latitudes for four out of the five pure px, while one yields a very high value of 348 ± 70 atoms (g Ca)-1 a-1. Values above 250 atoms (g Ca)-1 a-1 are also obtained from two less pure px containing 0.3 and 0.9% K and from one feldspar/quartz accumulate, indicating that the production rate from K may be higher than that from Ca. The weighted mean (excluding the outlier) of ~200 atoms (g Ca)-1 a-1 is in excellent agreement with Lal's [3] theoretical estimate. [1] Renne et al., EPSL 188 (2001) 435. [2] Schäfer et al., EPSL 167 (1999) 215. [3] Lal, EPSL 104 (1991) 424.

Structural, K-Ar and 40Ar-39Ar age studies of adularia K-feldspars from the Lizard Complex, England

International Nuclear Information System (INIS)

Halliday, A.N.; Mitchell, J.G.

1976-01-01

Conventional K-Ar analyses of fifteen adularia feldspars from the Lizard Complex yield ages between 181+-2 Ma and 220+-3 Ma (with one exception from Holseer Cove yielding an age of 156+-3 Ma). The feldspars are dominantly monoclinic but most contain a minor but constant proportion of triclinic material with variable triclinicity. An inverse correlation exists between triclinicity and K-Ar age interpreted as representing argon loss related to the structural state. Extrapolation of the data to zero triclinicity indicates a true age of 210-220 Ma. 40 Ar- 39 Ar stepwise degassing analyses yield plateau ages related to the K-Ar ages and not the crystallization age. The results can be explained in terms of postcrystallization Al-Si ordering resulting in argon loss from lattice sites which under normal diffusion conditions requires a range of activation energies. The Holseer Cove sample is monoclinic and an 40 Ar- 39 Ar stepheating analysis suggests a later crystallization at 160-170 Ma. Neither primary crystallization nor spontaneous ordering through time explain the origin of the triclinic adularia. It is suggested that ordering has been induced by the passage of low-temperature alkaline solutions at a subsequent point in geological time. Argon loss by ordering could explain the low ages found using both K-Ar and 40 Ar- 39 Ar stepheating methods when applied to feldspars in general. The 210-220 Ma, and 160-170 Ma hydrothermal events affected much of southwest England and are probably related to major geotectonic movements in western Europe. (Auth.)

Electronic-state distribution of Ar* produced from Ar+(2P3/2)/2e- collisional radiative recombination in an argon flowing afterglow

International Nuclear Information System (INIS)

Tsuji, Masaharu; Matsuzaki, Toshinori; Tsuji, Takeshi

2002-01-01

The Ar + /2e - collisional radiative recombination has been studied by observing UV and visible emissions of Ar* in an Ar flowing afterglow. In order to clarify recombination mechanism, the Ar + ( 2 P 3/2 ) spin-orbit component was selected by using a filter gas of the Ar + ( 2 P 1/2 ) component. Spectral analysis indicated that 34 Ar*(4p, 4d, 5p, 5d, 6s, 6p, 6d, 4p ' , 4d ' , 5p ' , 5d ' , 6s ' ) states in the 13.08-15.33 eV range are produced. The electronic-state distribution decreased with an increase in the excitation energy of Ar*, which was expressed by a Boltzmann electronic temperature of 0.54 eV. The formation ratios of the 4p: 4d + 5p + 5d + 6s + 6p + 6d: 4p ' : 4d ' + 5p ' + 5d ' + 6s ' states were 43%, 2.8%, 54%, and 0.31%, respectively. The high formation ratio of the 4p ' state having an Ar + ( 2 P 1/2 ) ion core in the Ar + ( 2 P 3/2 )/2e - recombination indicated that such a two-electron process as an electron transfer to an inner 3p orbital followed by excitation of a 3p electron to an outer 4p orbital occurs significantly. The higher formation ratios of 4d + 5p + 5d + 6s + 6p + 6d than those of 4d ' + 5p ' + 5d ' + 6s ' led us to conclude the formation of these upper states dominantly proceeds through one electron transfer to an outer nl orbital of Ar + ( 2 P 3/2 )

Geochronology and thermochronology by the 40Ar/39Ar method

International Nuclear Information System (INIS)

McDougall, I.; Harrison, T.M.

1988-01-01

This work is a response to the authors' belief that there is a need for a monograph on 40 Ar/ 39 Ar dating to provide concise knowledge concerning the application of this method to geological studies. They aim to provide a reasonably comprehensive but by no means exhaustive coverage of the principles and practices of 40 Ar/ 39 Ar dating, with emphasis on interpretation of results. In attempting to provide an overview of the current state of knowledge, they commonly cite examples from the available literature. They draw rather heavily upon their own work, because they feel comfortable with their own examples. (author)

A flavor of 40Ar-39Ar geochronology research at lIT Bombay

International Nuclear Information System (INIS)

Pande, Kanchan

2017-01-01

Geochronology based on radiogenic isotopes has become an invaluable tool in earth sciences. Several radioactive parent-daughter systems of varying half-lives such as Rb-Sr, Sm-Nd, K-Ar have been traditionally used by researchers for determining the timing of geological and planetary processes. 40 Ar- 39 Ar dating, a variant of the K-Ar system, is a well-established and versatile method of determining the eruptive ages of volcanic rocks and the ∼150-500° C thermal histories of a variety of more slowly cooled igneous and metamorphic rocks. In the 40 Ar- 39 Ar method the sample is irradiated by fast neutrons in a nuclear reactor to convert some of 39 K into 39 Ar. The fixed natural ratio 39 K/ 40 K provides estimate for the parent 40 K by measuring 39 Ar. In order to know the conversion factor of 39 K to 39 Ar and to take care of other nuclear interfering reactions a sample of known K-Ar age is irradiated along with the unknown. The age of the unknown is then derived by comparison with the monitor sample of known age

Vector analyzing power and cross section for the reactions 40Ar(d(pol),p)41Ar and 40Ar(d(pol),t)39Ar

International Nuclear Information System (INIS)

Sen, S.; Darden, S.E.; Yoh, W.A.; Berners, E.D.

1975-01-01

Angular distributions of vector analyzing power and cross section for the reactions 40 Ar(d,p) 41 Ar and 40 Ar(d,t) 39 Ar have been measured at an incident deuteron energy of 14.83 MeV. The bound-state data in the (d,p) reaction and the (d,t) data are compared to DWBA calculations. The data for the neutron-unbound states are analyzed in the framework of the DWBA using (i) a form factor for weakly bound neutron and (ii) a resonance form factor, following the approach of Vincent and Fortune. The j-dependence of the (d,p) vector analyzing power permits definite spin-parity assignments to be made for 19 neutron-bound and 4 neutron unbound states in 41 Ar with excitation energy up to 6.57 MeV. Tentative Jsup(π) assignments have been made for 3 states. The l-value for the 5.62 MeV states has been determined. Data for the observed unbound states are found to be equally well reproduced by the type (i) calculations as by the type (ii) calculations. The (d,t) vector cnalyzing power data show definite J-dependence although not as strongly as in the (d,p) reaction. For relatively weakly excited states a pre-knowledge of the l-value of the transition is desirable for an unambiguous spin assignment. In general, the J-dependence in the (d,t) vector analyzing power can be utilized for definitive Jsup(π) assignments. On this basis, Jsub(π) values have been assigned for seven states in 39 Ar with excitation energies up to 4.47MeV excitation. Possible spin values for three other states are suggested. Spectroscopic factors fo the states in 41 Ar and 39 Ar have been extracted and are in fair agreement with those obtained by other workers. (Auth.)

Spectroscopic analysis of visible and near UV light emitted by Ar7+ and Ar6+ ions produced in Ar8+-He and Ar8+-H2 collisions at 120 keV

International Nuclear Information System (INIS)

Boduch, P.; Chantepie, M.; Hennecart, D.; Husson, X.; Kucal, H.; Lecler, D.; Stolterfoht, N.; Druetta, M.; Fawcett, B.; Wilson, M.

1992-01-01

A spectroscopic analysis of light emitted in the 2000-6000A wavelength range by Ar 7+ and Ar 6+ ions produced in Ar 8+ -He and Ar 8+ -H 2 collisions at 120 keV is performed. Well resolved fine structure components of 5s-5p and 5p-5d transitions in Ar VIII following single electron capture are precisely measured. Predominant lines due to double electron capture are observed. In particular, strong lines observed both in Ar 8+ -He and Ar 8+ -H 2 collisions are attributed to Ryberg transitions 3snl-3sn'l' in Ar VII. Attempts at identifications are made for the transition 3dnl-3dn'l' (n=4, 5) with the help of ab initio calculations. Photon emission cross sections for individual lines are determined from the measured data. (orig.)

Development of an androgen reporter gene assay (AR-LUX) utilizing a human cell line with an endogenously regulated androgen receptor

NARCIS (Netherlands)

Blankvoort, B.M.G.; Groene, E.M. de; Meeteren-Kreikamp, A.P. van; Witkamp, R.F.; Rodenburg, R.J.T.; Aarts, J.M.M.J.G.

2001-01-01

The aim of the work described in this report is to develop and characterize a cell-based androgen reporter assay. For this purpose, the androgen receptor (AR) expressing human breast cancer cell line T47D was stably transfected with a luciferase gene under transcriptional control of the PB-ARE-2

Novel Junction-specific and Quantifiable In Situ Detection of AR-V7 and its Clinical Correlates in Metastatic Castration-resistant Prostate Cancer.

Science.gov (United States)

Zhu, Yezi; Sharp, Adam; Anderson, Courtney M; Silberstein, John L; Taylor, Maritza; Lu, Changxue; Zhao, Pei; De Marzo, Angelo M; Antonarakis, Emmanuel S; Wang, Mindy; Wu, Xingyong; Luo, Yuling; Su, Nan; Nava Rodrigues, Daniel; Figueiredo, Ines; Welti, Jonathan; Park, Emily; Ma, Xiao-Jun; Coleman, Ilsa; Morrissey, Colm; Plymate, Stephen R; Nelson, Peter S; de Bono, Johann S; Luo, Jun

2018-05-01

Androgen receptor splice variant 7 (AR-V7) has been implicated in resistance to abiraterone and enzalutamide treatment in men with metastatic castration-resistant prostate cancer (mCRPC). Tissue- or cell-based in situ detection of AR-V7, however, has been limited by lack of specificity. To address current limitations in precision measurement of AR-V7 by developing a novel junction-specific AR-V7 RNA in situ hybridization (RISH) assay compatible with automated quantification. We designed a RISH method to visualize single splice junctions in cells and tissue. Using the validated assay for junction-specific detection of the full-length AR (AR-FL) and AR-V7, we generated quantitative data, blinded to clinical data, for 63 prostate tumor biopsies. We evaluated clinical correlates of AR-FL/AR-V7 measurements, including association with prostate-specific antigen progression-free survival (PSA-PFS) and clinical and radiographic progression-free survival (PFS), in a subset of patients starting treatment with abiraterone or enzalutamide following biopsy. Quantitative AR-FL/AR-V7 data were generated from 56 of the 63 (88.9%) biopsy specimens examined, of which 44 were mCRPC biopsies. Positive AR-V7 signals were detected in 34.1% (15/44) mCRPC specimens, all of which also co-expressed AR-FL. The median AR-V7/AR-FL ratio was 11.9% (range 2.7-30.3%). Positive detection of AR-V7 was correlated with indicators of high disease burden at baseline. Among the 25 CRPC biopsies collected before treatment with abiraterone or enzalutamide, positive AR-V7 detection, but not higher AR-FL, was significantly associated with shorter PSA-PFS (hazard ratio 2.789, 95% confidence interval 1.12-6.95; p=0.0081). We report for the first time a RISH method for highly specific and quantifiable detection of splice junctions, allowing further characterization of AR-V7 and its clinical significance. Higher AR-V7 levels detected and quantified using a novel method were associated with poorer response to

In Situ Detection and Quantification of AR-V7, AR-FL, PSA, and KRAS Point Mutations in Circulating Tumor Cells.

Science.gov (United States)

El-Heliebi, Amin; Hille, Claudia; Laxman, Navya; Svedlund, Jessica; Haudum, Christoph; Ercan, Erkan; Kroneis, Thomas; Chen, Shukun; Smolle, Maria; Rossmann, Christopher; Krzywkowski, Tomasz; Ahlford, Annika; Darai, Evangelia; von Amsberg, Gunhild; Alsdorf, Winfried; König, Frank; Löhr, Matthias; de Kruijff, Inge; Riethdorf, Sabine; Gorges, Tobias M; Pantel, Klaus; Bauernhofer, Thomas; Nilsson, Mats; Sedlmayr, Peter

2018-03-01

Liquid biopsies can be used in castration-resistant prostate cancer (CRPC) to detect androgen receptor splice variant 7 (AR-V7), a splicing product of the androgen receptor. Patients with AR-V7-positive circulating tumor cells (CTCs) have greater benefit of taxane chemotherapy compared with novel hormonal therapies, indicating a treatment-selection biomarker. Likewise, in those with pancreatic cancer (PaCa), KRAS mutations act as prognostic biomarkers. Thus, there is an urgent need for technology investigating the expression and mutation status of CTCs. Here, we report an approach that adds AR-V7 or KRAS status to CTC enumeration, compatible with multiple CTC-isolation platforms. We studied 3 independent CTC-isolation devices (CellCollector, Parsortix, CellSearch) for the evaluation of AR-V7 or KRAS status of CTCs with in situ padlock probe technology. Padlock probes allow highly specific detection and visualization of transcripts on a cellular level. We applied padlock probes for detecting AR-V7, androgen receptor full length (AR-FL), and prostate-specific antigen (PSA) in CRPC and KRAS wild-type (wt) and mutant (mut) transcripts in PaCa in CTCs from 46 patients. In situ analysis showed that 71% (22 of 31) of CRPC patients had detectable AR-V7 expression ranging from low to high expression [1-76 rolling circle products (RCPs)/CTC]. In PaCa patients, 40% (6 of 15) had KRAS mut expressing CTCs with 1 to 8 RCPs/CTC. In situ padlock probe analysis revealed CTCs with no detectable cytokeratin expression but positivity for AR-V7 or KRAS mut transcripts. Padlock probe technology enables quantification of AR-V7, AR-FL, PSA, and KRAS mut/wt transcripts in CTCs. The technology is easily applicable in routine laboratories and compatible with multiple CTC-isolation devices. © 2017 American Association for Clinical Chemistry.

40Ar/39Ar dating of pyrite

International Nuclear Information System (INIS)

York, D.; Masliwec, A.; Kuybida, P.; Hanes, J.A.; Hall, C.M.; Kenyon, W.J.; Spooner, E.T.C.; Scott, S.D.

1982-01-01

To overcome difficulties encountered in the customary method of determining the age of mineralization of sulphide ore deposits by analysing silicate material, the sulphide minerals themselves have been examined to see if they contained sufficient potassium and argon for 40 Ar/ 39 Ar age determination. Initial results indicate that this is the case for pyrite from the Geco ore body in northwestern Ontario, Canada. (U.K.)

Developing a chronostratigraphic tool for climatic archives: absolute dating (K/Ar and 40Ar/39Ar) and paleo-magnetism applied to lavas

International Nuclear Information System (INIS)

Sasco, Romain

2015-01-01

that the volcanic activity of Ardeche can be divided in 3 phases: the oldest one (180±30 ka) took place in the northern part of the studied area and 2 younger phases are expressed in the South (31±4 ka and 24±8 ka).The study of the Canarian lavas produced 14 tie-points (9 out of 14 dated combining K-Ar and 40 Ar/ 39 Ar results). These data have been added to the available ones for the same time period. The published data have been selected on the basis of robust analytical protocols and accuracy. The 51 data finally selected are compared to available sedimentary stacks. Over the last 80 ka, the volcanic data corroborate the calibration of GLOPIS-75, initially based on volcanic and archaeo-magnetic data between 10-20 ka and the low intensity observed in the Laschamp excursion. Three newly produced data, dated between 45 and 60 ka, extend the database initially used to older periods and they are also consistent with the initial calibration of GLOPIS-75. Between 80 and 140 ka, though volcanic data have significant uncertainties (in age and/or paleo-intensity), they are consistent with available sedimentary records and validate their calibration level on the long-term. At a shorter time scale, volcanic data corroborate the intensity low reached during the older phase of the Blake excursion (120 ka) by PISO-1500, whereas this low does not appear in SINT-2000. For ages older than 140 ka, not only the volcanic data are scattered, but also the sedimentary records are different from one another and no conclusions could be drawn. Finally, 2 of our data suggest a brief geomagnetic event around 155 ka. Such an event cannot be seen on available global sedimentary stacks or models, even though some individual studies report a local geomagnetic event around 150 ka (Austria, Russia, and China Sea). (author) [fr

40Ar/39Ar dating of Quaternary volcanic ashes by multi-collection noble gas mass spectrometry: protocols, precision and intercalibration

DEFF Research Database (Denmark)

Storey, Michael; Rivera, Tiffany; Flude, Stephanie

) higher mass resolution allows hydrocarbon interferences to be pseudo resolved for the different argon isotopes; and (iv) multi-collection, allowing more data to be gathered in a fixed time in comparison with single-collector peak-switching measurements. We evaluate (i) protocols for detector inter......The recent availability of commercial high-resolution, multi-collector, noble gas mass spectrometers equipped with ion-counting electron multipliers provides new opportunities for improved precision in 40Ar/39Ar dating. This is particularly true for single crystal dating of Quaternary aged samples...... where potassium-bearing phenocrysts may contain relatively small amounts of radiogenic 40Ar. In 2005, the Quaternary Dating Laboratory, Roskilde University, installed a Nu-Instruments multi-collector Noblesse noble gas mass spectrometer, which is configured with a Faraday detector and three ion...

Photoionization study of HgAr

International Nuclear Information System (INIS)

Linn, S.H.; Brom, J.M. Jr.; Tzeng, W.; Ng, C.Y.

1985-01-01

Photoionization efficiency data for HgAr + have been obtained in the region of 680--1240 A. The ionization energy of HgAr was determined to be 10.217 +- 0.012 eV. This value allows the calculation of the dissociation energy of HgAr + to be 0.228 +- 0.017 eV. The relative probabilities for the formation of HgAr + via the reactions Ar* x Hg or Hg* x Ar→ HgAr + +e - with Ar* and Hg* prepared in high Rydberg states in the energy range of 10.22--15.79 eV were estimated. Although the radii for the 3d and 5s Rydberg ortitals of Ar have similar values, the probabilities for the formation of HgAr + from Hg x Ar* with Ar* in the 5s[3/2] 0 1 and 5s'[1/2] 0 1 Rydberg states are substantially greater than those when the Ar* excited atoms are in the 3d[1/2] 0 1 , 3s[3/2] 0 1 , and 3d'[3/2] 0 1 Rydberg levels. The ratio for the cross sections for the formation of HgAr + from Hg x Ar* with Ar* formed in the 3d[1/2] 0 1 and 4d[1/2] 0 1 states, as well as that with Ar* prepared in the 5d[1/2] 0 1 and 6d[1/2] 0 1 states, were found to be consistent with the predictions of the previous impact parameter calculations

Age measurements of potassium-bearing sulfide minerals by the 40Ar/39Ar technique

International Nuclear Information System (INIS)

Czamanske, G.K.; Lanphere, M.A.; Erd, R.C.; Blake, M.C. Jr.

1978-01-01

K-Ar ages have been determined for sulfide minerals for the first time. The occurrence of adequate amounts of potassium-bearing sulfides with ideal compositions K 3 Fe 10 S 14 (approximately 10 wt.% K) and KFe 2 S 3 (approximately 16 wt.% K) in samples from a mafic alkalic diatreme at Coyote Peak, California, prompted an attempt to date these materials. K 3 Fe 10 S 14 , a massive mineral with conchoidal fracture, gives an age of 29.4 +- 0.5 m.y. ( 40 Ar/ 39 Ar), indistinguishable from the 28.3 +- 0.4 m.y. ( 40 Ar/ 39 Ar) and 30.2 +- 1.0 m.y. (conventional K-Ar) ages obtained for associated phlogopite (8.7 wt.% K). KFe 2 S 3 , a bladed, fibrous sulfide, gives a younger age, 26.5 +- 0.5 m.y. ( 40 Ar/ 39 Ar), presumably owing to Ar loss. (Auth.)

Ar-Ar dating techniques for terrestrial meteorite impacts

Science.gov (United States)

Kelley, S. P.

2003-04-01

The ages of the largest (>100 km) known impacts on Earth are now well characterised. However the ages of many intermediate sized craters (20-100 km) are still poorly known, often the only constraints are stratigraphic - the difference between the target rock age and the age of crater filling sediments. The largest impacts result in significant melt bodies which cool to form igneous rocks and can be dated using conventional radiometric techniques. Smaller impacts give rise to thin bands of melted rock or melt clasts intimately mixed with country rock clasts in breccia deposits, and present much more of a challenge to dating. The Ar-Ar dating technique can address a wide variety of complex and heterogeneous samples associated with meteorite impacts and obtain reasonable ages. Ar-Ar results will be presented from a series of terrestrial meteorite impact craters including Boltysh (65.17±0.64 Ma, Strangways (646±42 Ma), and St Martin (220±32 Ma) and a Late Triassic spherule bed, possibly representing distal deposits from Manicouagan (214±1 Ma) crater. Samples from the Boltysh and Strangways craters demonstrate the importance of rapid cooling upon the retention of old ages in glassy impact rocks. A Late Triassic spherule bed in SW England is cemented by both carbonate and K-feldspar cements allowing Ar-Ar dating of fine grained cement to place a mimimum age upon the age of the associated impact. An age of 214.7±2.5 Ma places the deposit with errors of the age of the Manicouagan impact, raising the possibility that it may represent a distal deposit (the deposit lay around 2000 km away from the site of the Manicouagan crater during the Late Triassic). Finally the limits of the technique will be demonstrated using an attempt to date melt rocks from the St Martin Crater in Canada.

ScattAR

DEFF Research Database (Denmark)

Baldwin, Alex Dempster; Serafin, Stefania; Erkut, Cumhur

2017-01-01

We present an augmented reality (AR) audio application where scattering delay networks efficiently generate and organize a reverberator, based on room geometry scanned by an AR device. The application allows for real-time processing and updating of reflection path geometry. It provides a proof...

Ar-39/Ar-40 systematics of Allende inclusions

International Nuclear Information System (INIS)

Herzog, G.F.; Rutgers University, New Brunswick, NJ); Bence, A.E.

1980-01-01

A laser microprobe was used to measure the Ar isotopic contents of individual mineral grains in four neutron-irradiated Allende samples: two coarse-grained Ca-Al-rich inclusions, one fine-grained Ca-Al-rich inclusion, and one sample with matrix and miscellaneous chondrules. The following K-Ar ages (G.y.) were obtained after degassing low Ar retentive sites by preheating the samples for one hour at 675 C: matrix, 3.5 + or - 0.2 three miscellaneous chondrules, 4.4 + or - 0.1, 4.0 + or - 0.1, and 4.4 + or - 0.1 and the fine-grained inclusion, 4.5 + or - 0.2. The minerals in the coarse-grained Ca-Al-rich inclusions have ubiquitous chlorine, less than 10 ppm K and apparent ages ranging upwards from 4.6 G.y. to well over 10 G.y. Possible explanations for these apparent ages are atmospheric contamination, the decay of K-40 prior to the formation of the solar system, and the trapping of radiogenic Ar-40 lost by the matrix

AR4VI: AR as an Accessibility Tool for People with Visual Impairments.

Science.gov (United States)

Coughlan, James M; Miele, Joshua

2017-10-01

Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness - an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a range of accessibility barriers. Rather than being restricted to use by people with visual impairments, AR4VI is a compelling universal design approach offering benefits for mainstream applications as well.

40Ar/39Ar age spectra from the KBS Tuff, Koobi Fora Formation

International Nuclear Information System (INIS)

McDougall, I.

1981-01-01

40 Ar/ 39 Ar age spectra on anorthoclase phenocrysts from three pumice clasts in the KBS Tuff yield nearly ideal flat patterns, providing good evidence that the samples have remained undisturbed since crystallization. The ages are concordant at 1.88 = 0.02 Myr, and confirm that the KBS Tuff, a key marker bed in the Koobi Fora Formation, northern Kenya, is now very well dated. These results resolve the conflict between earlier 40 Ar/ 39 Ar and conventional K-Ar dating measurements on the KBS Tuff. (author)

40Ar/39Ar age spectra from the KBS Tuff, Koobi Fora Formation.

Science.gov (United States)

McDougall, Ian

1981-11-12

40 Ar/ 39 Ar age spectra on anorthoclase phenocrysts from three pumice clasts in the KBS Tuff yield nearly ideal flat patterns, providing good evidence that the samples have remained undisturbed since crystallization. The ages are concordant at 1.88±0.02 Myr, and confirm that the KBS Tuff, a key marker bed in the Koobi Fora Formation, northern Kenya, is now very well dated. These results resolve the conflict between earlier 40 Ar/ 39 Ar and conventional K-Ar dating measurements on the KBS Tuff.

MonitAR, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — We propose to develop MonitAR, an Augmented Reality (AR) system that provides procedure completion guidance to astronauts. MonitAR will replace guidance from mission...

The 40Ar/39Ar and K/Ar dating of lavas from the Hilo 1-km core hole, Hawaii Scientific Drilling Project

Science.gov (United States)

Sharp, W.D.; Turrin, B.D.; Renne, P.R.; Lanphere, M.A.

1996-01-01

Mauna Kea lava flows cored in the HilIo hole range in age from <200 ka to about 400 ka based on 40Ar/39Ar incremental heating and K-Ar analyses of 16 groundmass samples and one coexisting plagioclase. The lavas, all subaerially deposited, include a lower section consisting only of tholeiitic basalts and an upper section of interbedded alkalic, transitional tholeiitic, and tholeiitic basalts. The lower section has yielded predominantly complex, discordant 40Ar/39Ar age spectra that result from mobility of 40Ar and perhaps K, the presence of excess 40Ar, and redistribution of 39Ar by recoil. Comparison of K-Ar ages with 40Ar/39Ar integrated ages indicates that some of these samples have also lost 39Ar. Nevertheless, two plateau ages of 391 ?? 40 and 400 ?? 26 ka from deep in the hole, combined with data from the upper section, show that the tholeiitic section accumulated at an average rate of about 7 to 8 m/kyr and has an mean recurrence interval of 0.5 kyr/flow unit. Samples from the upper section yield relatively precise 40Ar/39Ar plateau and isotope correlation ages of 326 ?? 23, 241 ?? 5, 232 ?? 4, and 199 ?? 9 ka for depths of -415.7 m to -299.2 m. Within their uncertainty, these ages define a linear relationship with depth, with an average accumulation rate of 0.9 m/kyr and an average recurrence interval of 4.8 kyr/flow unit. The top of the Mauna Kea sequence at -280 m must be older than the plateau age of 132 ?? 32 ka, obtained for the basal Mauna Loa flow in the corehole. The upward decrease in lava accumulation rate is a consequence of the decreasing magma supply available to Mauna Kea as it rode the Pacific plate away from its magma source, the Hawaiian mantle plume. The age-depth relation in the core hole may be used to test and refine models that relate the growth of Mauna Kea to the thermal and compositional structure of the mantle plume.

AR4VI: AR as an Accessibility Tool for People with Visual Impairments

OpenAIRE

Coughlan, James M.; Miele, Joshua

2017-01-01

Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness – an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a r...

Ars disyecta Ars disyecta

Directory of Open Access Journals (Sweden)

Alejandra Castillo

2012-07-01

Full Text Available Bajo la nominación Ars Disyecta se busca exponer el vínculo entre artes visuales, feminismo y metamorfosis. Las prácticas artísticas feministas aquí presentadas se proponen perturbar el espacio metafórico heredado de la diferencia sexual (pensemos, por ejemplo, en las palabras engendramiento, matriz, vida, compenetración o invaginamiento. En este sentido, la nominación Ars disyecta pone en escena un conjunto de prácticas e intervenciones que intentan interrumpir la matriz de la diferencia, desestabilizando lo femenino desde aquellas figuras que se resisten a la lógica de la totalidad y de un tiempo propio. Buscando seguir la huella de un arte disyecto es que interrogaré en este ensayo aquellas autorías feministas que en el arte contemporáneo trafican con las huellas del contagio, la mutación y la alteridad.This article aims to present the relation between visual arts, feminism I and metamorphosis. The feminist artistic practices portrayed in this article attempt to question categories inherited from the metaphor of sexual difference such as engendering, matrix and life. From this perspective, Ars disyecta will establish a set of artistic practices and interventions that intend to interrupt the proper idea of «feminine difference». Following this line of argument, I will discuss in this article a few contemporary feminist works of art that could be defined by words such as contagious, mutation and otherness.

40Ar-39Ar method for age estimation: principles, technique and application in orogenic regions

International Nuclear Information System (INIS)

Dalmejer, R.

1984-01-01

A variety of the K-Ar method for age estimation by 40 Ar/ 39 Ar recently developed is described. This method doesn't require direct analysis of potassium, its content is calculated as a function of 39 Ar, which is formed from 39 K under neutron activation. Errors resulted from interactions between potassium and calcium nuclei with neutrons are considered. The attention is paid to the technique of gradual heating, used in 40 Ar- 39 Ar method, and of obtaining age spectrum. Aplicabilities of isochronous diagram is discussed for the case of presence of excessive argon in a sample. Examples of 40 Ar- 39 Ar method application for dating events in orogenic regions are presented

Evidence of interatomic Coulombic decay in ArKr after Ar 2p Auger decay

International Nuclear Information System (INIS)

Morishita, Y; Saito, N; Suzuki, I H; Fukuzawa, H; Liu, X-J; Sakai, K; Pruemper, G; Ueda, K; Iwayama, H; Nagaya, K; Yao, M; Kreidi, K; Schoeffler, M; Jahnke, T; Schoessler, S; Doerner, R; Weber, T; Harries, J; Tamenori, Y

2008-01-01

We have identified interatomic Coulombic decay (ICD) processes in the ArKr dimer following Ar 2p Auger decay, using momentum-resolved electron-ion-ion coincidence spectroscopy and simultaneously determining the kinetic energy of the ICD electron and the KER between Ar 2+ and Kr + . We find that the spin-conserved ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 1 D and 3 P, respectively, ionizing the Kr atom, are significantly stronger than the spin-flip ICD processes in which Ar 2+ (3p -3 3d) 1 P and 3 P decay to Ar 2+ (3p -2 ) 3 P and 1 D, respectively

Feldspar 40Ar/39Ar dating of ICDP PALEOVAN cores

Science.gov (United States)

Engelhardt, Jonathan Franz; Sudo, Masafumi; Stockhecke, Mona; Oberhänsli, Roland

2017-11-01

Volcaniclastic fall deposits in ICDP drilling cores from Lake Van, Turkey, contain sodium-rich sanidine and calcium-rich anorthoclase, which both comprise a variety of textural zoning and inclusions. An age model records the lake's history and is based on climate-stratigraphic correlations, tephrostratigraphy, paleomagnetics, and earlier 40Ar/39Ar analyses (Stockhecke et al., 2014b). Results from total fusion and stepwise heating 40Ar/39Ar analyses presented in this study allow for the comparison of radiometric constraints from texturally diversified feldspar and the multi-proxy lacustrine age model and vice versa. This study has investigated several grain-size fractions of feldspar from 13 volcaniclastic units. The feldspars show textural features that are visible in cathodoluminescence (CL) or back-scattered electron (BSE) images and can be subdivided into three dominant zoning-types: (1) compositional zoning, (2) round pseudo-oscillatory zoning and (3) resorbed and patchy zoning (Ginibre et al., 2004). Round pseudo-oscillatory zoning records a sensitive alternation of Fe and Ca that also reflects resorption processes. This is only visible in CL images. Compositional zoning reflects anticorrelated anorthite and orthoclase contents and is visible in BSE. Eleven inverse isochron ages from total fusion and three from stepwise heating analyses fit the age model. Four experiments resulted in older inverse isochron ages that do not concur with the model within 2σ uncertainties and that deviate from 1 ka to 17 ka minimum. C- and R-type zoning are interpreted as representing growth in magma chamber cupolas, as wall mushes, or in narrow conduits. Persistent compositions of PO-type crystals and abundant surfaces recording dissolution features correspond to formation within a magma chamber. C-type zoning and R-type zoning have revealed an irregular incorporation of melt and fluid inclusions. These two types of zoning in feldspar are interpreted as preferentially

Photodissociation dynamics of Ar2(+) and Ar3(+) excited by 527 nm photons.

Science.gov (United States)

Lepère, V; Picard, Y J; Barat, M; Fayeton, J A; Lucas, B; Béroff, K

2009-05-21

The photofragmentation dynamics of Ar(2)(+) and Ar(3)(+) clusters has been investigated at a 527 nm wavelength (2.35 eV) using a setup that allows simultaneous detection of the ionic and neutral fragments in a coincidence experiment. Measurement of positions and times of flight enables in principle a complete description of the fragmentation dynamics. The photofragmentation dynamics of Ar(3)(+) clusters is similar to that of Ar(2)(+) with, in addition, the ejection of a third fragment that can be neutral or ionized via a resonant electron capture. This is attributed to the triangular geometry of the Ar(3)(+) ion.

The effects of acid treatment and sample preparation on 40Ar/39Ar ages

Science.gov (United States)

Morgan, L. E.; Davidheiser, B.; Kuiper, K.; Wijbrans, J. R.

2011-12-01

Practitioners of K-Ar and 40Ar/39Ar geochronology regularly use dilute acids (typically 5-10% hydrofluoric acid (HF)) to clean mineral grains prior to irradiation (in the case of 40Ar/39Ar), and analysis (e.g. Evernden and Curtis, 1965; Dalrymple, 1967). This treatment has been shown to reduce contamination from atmospheric Ar, which consists largely of 40Ar and thus must be differentiated from radiogenic 40Ar* (Evernden and Curtis, 1965). Acid treatments can also remove fine grained material attached to mineral grains, such as glass shards or devitrified glass, which can affect analyses and is difficult to remove by other means (Evernden and Curtis, 1965). Such treatments were originally examined for their efficacy in reducing atmospheric argon contamination (Dalrymple, 1967) but were not assessed for the possibility of leaching Ar* or K differentially, which would affect both K-Ar and 40Ar/39Ar ages. Indeed, Evernden and Curtis (1965) state that they are simply removing the "outer portions of the crystals" and apparently do not account for the potential for leaching of 40Ar* or K from the mass of their host mineral. Moreover, the capabilities of the K-Ar system in the 1960s was limited to a precision of ca. 3-4% on samples of 1-3 Ma (Cox and Dalrymple, 1967). Effects of smaller magnitude could not have been detected at the time. As the developments of the 40Ar/39Ar system and modern mass spectrometer technology have allowed for precision to approach 0.1%, the potential effects of acid treatment during sample preparation warrant revisiting. Additionally, the use of Calgon for sample disintegration has not previously been quantitatively assessed but is used extensively in some laboratories. Here we present a series of experiments from co-irradiated Fish Canyon sanidine (FCs) and Mes-4 (Kuiper et al., 2008). FCs is used as the mineral standard following standard procedures. Mes-4 splits were treated with H2O (10 minutes, ultrasonic), Calgon (10%, overnight at 50�

Dissociative recombination of rare gas hydride ions: II. ArH+

International Nuclear Information System (INIS)

Mitchell, J B A; Novotny, O; LeGarrec, J L; Florescu-Mitchell, A; Rebrion-Rowe, C; Stolyarov, A V; Child, M S; Svendsen, A; Ghazaly, M A El; Andersen, L H

2005-01-01

A storage ring measurement of the rate coefficient for the production of neutral Ar in e + ArH + collisions is described. It is found that the recombination rate is too small to measure at low centre-of-mass energies but the combined rate coefficient for dissociative recombination and dissociative excitation increases above 2.5 eV displaying peaks centred at 7.5 eV, 16 and 26 eV. Calculated potential energy curves for the ground and excited states of ArH + are presented and these aid in the elucidation of the recombination and excitation processes observed at higher energies. The implications for plasma modelling are discussed. (letter to the editor)

40Ar/36Ar in MORB glasses: Constraints on atmosphere and mantle evolution

International Nuclear Information System (INIS)

Sarda, P.; Staudacher, T.; Allegre, C.J.; Paris-7 Univ., 75

1985-01-01

Argon isotopic composition measurements of MORB glassy samples from the Pacific, Atlantic and Indian Oceans are performed. There is a very large scatter in the 40 Ar/ 36 Ar ratio, from 980 up to 24,400 for bulk rock analyses, which is mainly due to atmospheric contamination: Using the stepwise heating technique, very high ratios are obtained, from 15,000 up to 25,250 which is the highest 40 Ar/ 36 Ar ratio ever measured in MORB. We establish a negative correlation between the highest 40 Ar/ 36 Ar results from stepwise heating and 87 Sr/ 86 Sr ratios, which is perfectly consistent with a two-layered mantle structure. From both 40 Ar and 129 Xe MORB systematics a model is proposed for the kinetics of degassing: a very early and extensive burst, with a time constant of approx.= 4 My, is followed by a slower process of present day type, with a time constant of approx.= 0.5 Gy. The mean age of the atmosphere is so determined to be around 4.4 Gy. (orig./WB)

Levels in 45K and 46K excited by the β decay of 45Ar and 46Ar

International Nuclear Information System (INIS)

Huck, A.; Klotz, G.; Knipper, A.; Miehe, C.; Walter, G.

1979-01-01

The nuclides 45 Ar and 46 Ar have been produced by spallation reactions on vanadium targets at Esub(p)=600MeV. The subsequent decays to 45 K and 46 K states have been studied. An intensity of 98.6+-0.6% was measured for the β transition of the 1.94MeV state in 46 K. A decay scheme involving 13 β branches has been established for 45 Ar, and the corresponding log values have been deduced. Eleven states are reported for the first time in the decay scheme of 45 Ar 1.42, 1.47, 1.72, 2.52, 2.57, 2.75, 3.31, 3.99, 4.04, 4.36 and 4.57MeV. From the lifetime, tau=4.6+-0.6ns, deduced from γ-γ delayed coincidences, the angular momentum of the 1081keV level has been established as (7/2) - on the basis of the transition strength of its γ decay. A survey on the 1fsub(7/2)→1dsub(3/2)M2 transition in odd K nuclei is presented and the observed hindrance factors are discussed

Formation of doubly charged argon ions, Ar2+, from long-lived highly excited argon ions, Arsup(+*), colliding with Ar and N2 gases

International Nuclear Information System (INIS)

Okuno, Kazuhiko

1976-01-01

Formation of Ar 2+ from long-lived highly excited Ar + * colliding with Ar and N 2 gases is studied by means of a tandem mass spectrometer. The tandem mass spectrometer used consists of two mass analyzers connected in series and a collision chamber located in between. The collision chamber is electrically floated and can be set at a desired potential, so that one can identify the fast ions (resulting from the primary ions) and the slow ions (secondary ions) in the mass spectra taken by the second mass analyzer. When the first mass analyzer is tuned to Ar + , peaks corresponding Ar 2+ appear in the second mass spectra. From the analysis of variation of mass positions and heights of these peaks with the change of the potential and pressure of the collision chamber, the Ar 2+ is concluded to result from the primary Ar + in collision with gas molecules and wall surface. From the threshold behavior of the product Ar 2+ with the electron energy in the ion source, three sets of long-lived highly excited Ar + * states (Rydberg states) are found to be responsible for this process. They are 3s 2 3p 4 ( 3 P)nl, 3s 2 3p 4 ( 1 D 2 )n'l and 3s 2 3p 4 ( 1 S 0 )n''l converging to Ar 2+3 Psub(2.1.0) (43.38, 43.51, 43.57 eV), 1 D 2 (45.11 eV) and 1 S 0 (47.50 eV), respectively. Their fractional ratio in the primary Ar + beam is determined as 3.0:1.0:1.2 which is close to that of multiplicities of the states concerned. The autoionization mechanism reported by other investigators to be responsible for the formation of Ar 2+ in Aston band or tandem mass spectra is found to be negligible. The cross sections of formation of Ar 2+ from Ar + * colliding with Ar and N 2 increase in proportion to the 1.15th power of the collision energy in the range from 750 eV to 2.5 keV. At the collision energy of 1.0 keV, they are 2.0x10 -20 /F cm 2 for Ar target and 6.6x10 -20 /F cm 2 for N 2 target, where the fractional density of Ar + * is estimated to be 0.7x10 -4 -4 . (auth.)

CNPY2 inhibits MYLIP-mediated AR protein degradation in prostate cancer cells.

Science.gov (United States)

Ito, Saya; Ueno, Akihisa; Ueda, Takashi; Nakagawa, Hideo; Taniguchi, Hidefumi; Kayukawa, Naruhiro; Fujihara-Iwata, Atsuko; Hongo, Fumiya; Okihara, Koji; Ukimura, Osamu

2018-04-03

The androgen receptor (AR) is a ligand-dependent transcription factor that promotes prostate cancer (PC) cell growth through control of target gene expression. This report suggests that Canopy FGF signaling regulator 2 (CNPY2) controls AR protein levels in PC cells. We found that AR was ubiquitinated by an E3 ubiquitin ligase, myosin regulatory light chain interacting protein (MYLIP) and then degraded through the ubiquitin-proteasome pathway. CNPY2 decreased the ubiquitination activity of MYLIP by inhibition of interaction between MYLIP and UBE2D1, an E2 ubiquitin ligase. CNPY2 up-regulated gene expression of AR target genes such as KLK3 gene which encodes the prostate specific antigen (PSA) and promoted cell growth of PC cells. The cell growth inhibition by CNPY2 knockdown was rescued by AR overexpression. Furthermore, positive correlation of expression levels between CNPY2 and AR/AR target genes was observed in tissue samples from human prostate cancer patients. Together, these results suggested that CNPY2 promoted cell growth of PC cells by inhibition of AR protein degradation through MYLIP-mediated AR ubiquitination.

40Ar/39Ar age and thermal history of the Kirin chondrite

International Nuclear Information System (INIS)

Wang, S.; McDougall, I.; Tetley, N.; Harrison, T.M.

1980-01-01

The Kirin meteorite, a large (> 2800 kg) H5 chondrite, fell in Kirin Province, China in 1976. A sample from each of the two largest fragments (K-1. K-2) yield 40 Ar/ 39 Ar total fusion ages of 3.63 +- 0.02 b.y. and 2.78 +- 0.02 b.y. respectively. 40 Ar/ 40 Ar age spectra show typical diffusional argon loss profiles. Maximum apparent ages of 4.36 b.y. (K-1) and approx. 4.0 b.y. (K-2) are interpreted as possible minimum estimates for the age of crystallization of the parent body. (orig./ME)

Astronomically calibrated 40Ar/39Ar age for the Toba supereruption and global synchronization of late Quaternary records

Science.gov (United States)

Storey, Michael; Roberts, Richard G.; Saidin, Mokhtar

2012-11-01

The Toba supereruption in Sumatra, ∼74 thousand years (ka) ago, was the largest terrestrial volcanic event of the Quaternary. Ash and sulfate aerosols were deposited in both hemispheres, forming a time-marker horizon that can be used to synchronize late Quaternary records globally. A precise numerical age for this event has proved elusive, with dating uncertainties larger than the millennial-scale climate cycles that characterized this period. We report an astronomically calibrated 40Ar/39Ar age of 73.88 ± 0.32 ka (1σ, full external errors) for sanidine crystals extracted from Toba deposits in the Lenggong Valley, Malaysia, 350 km from the eruption source and 6 km from an archaeological site with stone artifacts buried by ash. If these artifacts were made by Homo sapiens, as has been suggested, then our age indicates that modern humans had reached Southeast Asia by ∼74 ka ago. Our 40Ar/39Ar age is an order-of-magnitude more precise than previous estimates, resolving the timing of the eruption to the middle of the cold interval between Dansgaard-Oeschger events 20 and 19, when a peak in sulfate concentration occurred as registered by Greenland ice cores. This peak is followed by a ∼10 °C drop in the Greenland surface temperature over ∼150 y, revealing the possible climatic impact of the eruption. Our 40Ar/39Ar age also provides a high-precision calibration point for other ice, marine, and terrestrial archives containing Toba sulfates and ash, facilitating their global synchronization at unprecedented resolution for a critical period in Earth and human history beyond the range of 14C dating.

The effects of retrograde reactions and of diffusion on 39Ar-40Ar ages of micas

DEFF Research Database (Denmark)

Allaz, Julien; Engi, Martin; Berger, Alfons

2011-01-01

Effects of metamorphic reactions occurring during decompression were explored to understand their influence on 39Ar-40Ar ages of micas. Monometamorphic metasediments from the Lepontine Alps (Switzerland) were studied. Collected samples reached lower amphibolite facies during the Barrovian....... XRD-data indicated that some mineral separates prepared for Ar-Ar stepwise heating analysis were monomineralic, whereas others were composed of two white micas (muscovite with paragonite or margarite), or biotite and chlorite. In monomineralic samples 37Ar/39Ar and 38Ar/39Ar (proportional to Ca....../K and Cl/K ratios) did not change and the resulting ages can be interpreted unambiguously. In mineral separates containing two white micas, Ca/K and Cl/K ratios were variable, reflecting non-simultaneous laboratory degassing of the two heterochemical Ar-reservoirs. These ratios were used to identify each...

Geochronology and thermochronology by the sup 40 Ar/ sup 39 Ar method

Energy Technology Data Exchange (ETDEWEB)

McDougall, I. (Australian National Univ., Canberra (Australia)); Harrison, T.M. (State Univ. of New York, Albany, NY (USA))

1988-01-01

This work is a response to the authors' belief that there is a need for a monograph on {sup 40}Ar/{sup 39}Ar dating to provide concise knowledge concerning the application of this method to geological studies. They aim to provide a reasonably comprehensive but by no means exhaustive coverage of the principles and practices of {sup 40}Ar/{sup 39}Ar dating, with emphasis on interpretation of results. In attempting to provide an overview of the current state of knowledge, they commonly cite examples from the available literature. They draw rather heavily upon their own work, because they feel comfortable with their own examples. (author).

Beam-induced back-streaming electron suppression analysis for an accelerator type neutron generator designed for 40Ar/39Ar geochronology.

Science.gov (United States)

Waltz, Cory; Ayllon, Mauricio; Becker, Tim; Bernstein, Lee; Leung, Ka-Ngo; Kirsch, Leo; Renne, Paul; Bibber, Karl Van

2017-07-01

A facility based on a next-generation, high-flux D-D neutron generator has been commissioned and it is now operational at the University of California, Berkeley. The current generator designed for 40 Ar/ 39 Ar dating of geological materials produces nearly monoenergetic 2.45MeV neutrons at outputs of 10 8 n/s. The narrow energy range is advantageous relative to the 235 U fission spectrum neutrons due to (i) reduced 39 Ar recoil energy, (ii) minimized production of interfering argon isotopes from K, Ca, and Cl, and (iii) reduced total activity for radiological safety and waste generation. Calculations provided show that future conditioning at higher currents and voltages will allow for a neutron output of over 10 10 n/s, which is a necessary requirement for production of measurable quantities of 39 Ar through the reaction 39 K(n,p) 39 Ar. A significant problem encountered with increasing deuteron current was beam-induced electron backstreaming. Two methods of suppressing secondary electrons resulting from the deuterium beam striking the target were tested: the application of static electric and magnetic fields. Computational simulations of both techniques were done using a finite element analysis in COMSOL Multiphysics ® . Experimental tests verified these simulations. The most reliable suppression was achieved via the implementation of an electrostatic shroud with a voltage offset of -800V relative to the target. Copyright © 2017. Published by Elsevier Ltd.

Alignment and orientation of Ar+ in He+-Ar collisions

International Nuclear Information System (INIS)

Moudry, B.W.; Yenen, O.; Jaecks, D.H.

1994-01-01

We have measured the alignment and orientation parameters of the 2 F 7/2 0 and 2 F 5/2 0 states of Ar + formed in the two-electron process; He + +Ar→He(1s 2 )+Ar + (3p 4 4p'). These have been measured at a collision energy of 0.25 keV/amu and for scattering angles ranging from 0.94 to 3.75 . First, by comparing the orientation prameter for the Ar + [(3p 4 [ 1 D]4p' 2 F 7/2 0 ] and the Ar + [(3p 4 [ 1 D]4p' 2 F 5/2 0 ] states, we have experimentally determined the importance of the spin-dependent interactions for the present collision system, by testing the Percival-Seaton hypothesis of spin independence. If the Percival-Seaton hypothesis holds for this system, the orientation parameter should be J-independent. Secondly, the magnitude of the orientation prameter can be interpreted as resulting from the collective circulation of the unexcited 3p 4 electrons and the excited 4p electron. The direction of this collective circulation is compared to the propensity rule for colliding di-atom systems. (orig.)

3 to 15 keV Ar+ induced Auger electron emission from Si and Ar

International Nuclear Information System (INIS)

Kempf, J.; Kaus, G.

1977-01-01

Ar + induced Auger electrons from Si and Ar were investigated at bombardment energies between 3-15 keV and target currents of a few μA. The Auger electron yields were compared with secondary ion yields of Si and Ar by simultaneous SIMS-AES measurements. In the ion induced Auger spectra of Si five Auger peaks and in the Ar spectra three Auger peaks were observed. The ion induced Auger electron yield of Si and Ar were found to be strongly dependent upon the primary ion energy. 'Bulk like' and 'atomic like' Auger transitions of ion induced Auger electrons of Si were observed. (orig.) [de

Androgen Receptor-Mediated Growth Suppression of HPr-1AR and PC3-Lenti-AR Prostate Epithelial Cells.

Directory of Open Access Journals (Sweden)

Young-Chae Kim

Full Text Available The androgen receptor (AR mediates the developmental, physiologic, and pathologic effects of androgens including 5α-dihydrotestosterone (DHT. However, the mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells are not well understood, though they are central to prostate development, homeostasis, and neoplasia. Here, we identify androgen-responsive genes that restrain cell cycle progression and proliferation of human prostate epithelial cell lines (HPr-1AR and PC3-Lenti-AR, and we investigate the mechanisms through which AR regulates their expression. DHT inhibited proliferation of HPr-1AR and PC3-Lenti-AR, and cell cycle analysis revealed a prolonged G1 interval. In the cell cycle, the G1/S-phase transition is initiated by the activity of cyclin D and cyclin-dependent kinase (CDK complexes, which relieve growth suppression. In HPr-1AR, cyclin D1/2 and CDK4/6 mRNAs were androgen-repressed, whereas CDK inhibitor, CDKN1A, mRNA was androgen-induced. The regulation of these transcripts was AR-dependent, and involved multiple mechanisms. Similar AR-mediated down-regulation of CDK4/6 mRNAs and up-regulation of CDKN1A mRNA occurred in PC3-Lenti-AR. Further, CDK4/6 overexpression suppressed DHT-inhibited cell cycle progression and proliferation of HPr-1AR and PC3-Lenti-AR, whereas CDKN1A overexpression induced cell cycle arrest. We therefore propose that AR-mediated growth suppression of HPr-1AR involves cyclin D1 mRNA decay, transcriptional repression of cyclin D2 and CDK4/6, and transcriptional activation of CDKN1A, which serve to decrease CDK4/6 activity. AR-mediated inhibition of PC3-Lenti-AR proliferation occurs through a similar mechanism, albeit without down-regulation of cyclin D. Our findings provide insight into AR-mediated regulation of prostate epithelial cell proliferation.

Analysis list: Ar [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Ar Gonad,Kidney,Prostate + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/targe...t/Ar.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Ar.5.tsv http://dbarchive.biosciencedbc.jp/...kyushu-u/mm9/target/Ar.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Ar.Gonad.tsv,http://dbarchive.bioscience...dbc.jp/kyushu-u/mm9/colo/Ar.Kidney.tsv,http://dbarchive.bioscienced...bc.jp/kyushu-u/mm9/colo/Ar.Prostate.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Gonad.gml,http://dbarchive.bioscience

Geological evolution of the Boset-Bericha Volcanic Complex, Main Ethiopian Rift: 40Ar/39Ar evidence for episodic Pleistocene to Holocene volcanism

Science.gov (United States)

Siegburg, Melanie; Gernon, Thomas M.; Bull, Jonathan M.; Keir, Derek; Barfod, Dan N.; Taylor, Rex N.; Abebe, Bekele; Ayele, Atalay

2018-02-01

The Boset-Bericha Volcanic Complex (BBVC) is one of the largest stratovolcanoes of the northern Main Ethiopian Rift (MER). However, very little is known about its eruptive history, despite the fact that approximately 4 million people live within 100 km of the complex. Here, we combine field observations, morphometric analysis using high-resolution LiDAR data, geochemistry and 40Ar/39Ar geochronology to report the first detailed account of the geological evolution of the BBVC, with a focus on extensive young lava flows covering the two edifices, Gudda and Bericha. These lavas exhibit a bimodal composition ranging dominantly from basaltic rift floor lavas and scoria cones, to pantelleritic trachytes and rhyolite flows at Gudda, and comenditic rhyolites at Bericha. Further, several intermediate compositions are associated with fissure vents along the Boset-Kone segment that also appear to link the silicic centres. We divide the BBVC broadly into four main eruptive stages, comprising: (1) early rift floor emplacement, (2) formation of Gudda Volcano within two main cycles, separated by caldera formation, (3) formation of the Bericha Volcano, and (4) sporadic fissure eruptions. Our new 40Ar/39Ar geochronology, targeting a representative array of these flows, provides evidence for episodic activity at the BBVC from 120 ka to the present-day. We find that low-volume mafic episodes are more frequent ( 10 ka cyclicity) than felsic episodes ( 100 ka cyclicity), but the latter are more voluminous. Over the last 30 ka, mafic to intermediate fissure activity might have reinvigorated felsic activity (over the last 16 ka), manifested as peralkaline lava flows and pyroclastic deposits at Gudda and Bericha. Felsic episodes have on average a higher eruption rate (2-5/1000 years) and productivity at Gudda compared to Bericha (1-2/1000 years). The young age of lavas and current fumarolic activity along the fault system, suggest that the BBVC is still potentially active. Coincident

AR, HEA and AAS in Rural Development Projects--Benchmarking towards the Best Processes.

Science.gov (United States)

Westermarck, Harri

In most countries, agricultural research (AR), institutions of higher education in agriculture (HEA), and agricultural advisory services (AAS) function as separate agencies. So far, in most countries, AR, HEA, and AAS have not had a common vision for rural development. In Finland, domination of agricultural production in Finland has led to a lack…

Ramon Llull's Ars Magna

DEFF Research Database (Denmark)

Jensen, Thessa

2017-01-01

might be a viable and valuable approach to understand some of the challenges and possibilities found in computer science and ethics. Vita Llull was born in 1232 in Palma de Mallorca, a melting pot for different cul-tures and religions at the time. Being educated at the king’s court, Llull learned...... of belief, life, and God as such. Computer Science? Llull was an inspiration for later scientists, most notably Giordano Bruno, Athanasius Kirchner, Agrippa of Nettesheim and Gottfried Wilhelm Leibniz, whose dissertation De Arte Combinatoria begins with a discussion of Llull’s Ars Magna. Umberto Eco also......-ple of Mallorca have since tried to have Llull canonised as a saint. Ars Magna A few years before his death Llull began to write the most thorough and final version of his Ars Magna, the Ars Generalis Ultima [3]. The books explain the different figures of the Ars, its principles, questions, descriptions...

Timing and processes for exhumation of HP/LT rocks of the southern Brooks Range (AK): Insight from combined geochemistry and 40Ar/39Ar thermochronology of white mica

Science.gov (United States)

O'Brien, T.; Miller, E. L.; Grove, M. J.; Hayden, L. A.

2015-12-01

The obduction of an island arc onto the Arctic Alaska continental margin in the Jura-Cretaceous led to southward subduction of continental crust and high-pressure/low-temperature (HP/LT) epidote-blueschist facies metamorphism in the southern Brooks Range (BR). A regionally developed greenschist facies normal-sense shear zone system along the southern margin of the BR suggests that extensional faulting had an influential role in the exhumation of the metamorphic core. To better constrain the exhumation history of the metamorphic core of the BR, samples were collected from a N-S transect through the metamorphic core of the orogen. Electron microprobe (EMP) analyses of white micas reveal that they are composed of phengite (Si > 3.0 pfu) or a combination of phengite + paragonite. Si-content of phengites reveal a southward increase in Si from 3.1 to 3.4 pfu (corresponding to an increase in pressure). Si-contents in higher-P phengites are scattered, reflecting subsequent muscovite growth. The Si trend is matched by a southward increase in the 40Ar/39Ar total gas ages of white micas. Phengite from the north are characterized by younger ages (~115 Ma) and flatter 40Ar/39Ar spectra. Farther south, phengites and paragonites yield older 40Ar/39Ar ages. These samples yield convex, staircase 40Ar/39Ar spectra that initiate ~115-120 Ma and flatten-out ~130-138 Ma. Modeling using MacArgon proposes that an initial cooling of HP/LT metamorphism occurred ~130-138 Ma, recorded in the high-Si phengites and paragonites. Following initial cooling, modeling suggests HP/LT rocks stalled in the greenschist facies field before subsequent exhumation, resulting in the staircase 40Ar/39Ar spectra. Flatter 40Ar/39Ar spectra recorded by the northern samples and modeling of 40Ar/39Ar results from the southern samples suggest that these rocks from metamorphic core of the BR were exhumed to temperatures < 300°C by ~115 Ma.

Pre-Himalayan tectono-magmatic imprints in the Darjeeling-Sikkim Himalaya (DSH) constrained by 40Ar/39Ar dating of muscovite

Science.gov (United States)

Acharyya, Subhrangsu K.; Ghosh, Subhajit; Mandal, Nibir; Bose, Santanu; Pande, Kanchan

2017-09-01

The Lower Lesser Himalayan Sequence (L-LHS) in Darjeeling-Sikkim Himalaya (DSH) displays intensely deformed, low-grade meta-sedimentary rocks, frequently intervened by granite intrusives of varied scales. The principal motivation of our present study is to constrain the timing of this granitic event. Using 40Ar/39Ar geochronology, we dated muscovite from pegmatites emplaced along the earliest fabric in the low grade Daling phyllite, and obtained ∼1850 Ma Ar-Ar muscovite cooling age, which is broadly coeval with crystallization ages of Lingtse granite protolith (e.g., 1800-1850 Ma U-Pb zircon ages) reported from the L-LHS. We present here field observations to show the imprints (tectonic fabrics) of multiple ductile deformation episodes in the LHS terrain. The earliest penetrative fabric, axial planar to N-S trending reclined folds, suggest a regional tectonic event in the DSH prior to the active phase of Indo-Asia collision. Based on the age of granitic bodies and their structural correlation with the earliest fabric, we propose that the L-LHS as a distinct convergent tectono-magmatic belt, delineating the northern margin of Indian craton in the framework of the ∼1850 Ma Columbia supercontinent assembly.

Atmospheric pressure plasma jet utilizing Ar and Ar/H2O mixtures and its applications to bacteria inactivation

International Nuclear Information System (INIS)

Cheng Cheng; Shen Jie; Xiao De-Zhi; Xie Hong-Bing; Lan Yan; Fang Shi-Dong; Meng Yue-Dong; Chu Paul K

2014-01-01

An atmospheric pressure plasma jet generated with Ar with H 2 O vapor is characterized and applied to inactivation of Bacillus subtilis spores. The emission spectra obtained from Ar/H 2 O plasma shows a higher intensity of OH radicals compared to pure argon at a specified H 2 O concentration. The gas temperature is estimated by comparing the simulated spectra of the OH band with experimental spectra. The excitation electron temperature is determined from the Boltzmann's plots and Stark broadening of the hydrogen Balmer H β line is applied to measure the electron density. The gas temperature, excitation electron temperature, and electron density of the plasma jet decrease with the increase of water vapor concentration at a fixed input voltage. The bacteria inactivation rate increases with the increase of OH generation reaching a maximum reduction at 2.6% (v/v) water vapor. Our results also show that the OH radicals generated by the Ar/H 2 O plasma jet only makes a limited contribution to spore inactivation and the shape change of the spores before and after plasma irradiation is discussed. (physics of gases, plasmas, and electric discharges)

The celecoxib derivatives AR-12 and AR-14 induce autophagy and clear prion-infected cells from prions.

Science.gov (United States)

Abdulrahman, Basant A; Abdelaziz, Dalia; Thapa, Simrika; Lu, Li; Jain, Shubha; Gilch, Sabine; Proniuk, Stefan; Zukiwski, Alexander; Schatzl, Hermann M

2017-12-14

Prion diseases are fatal infectious neurodegenerative disorders that affect both humans and animals. The autocatalytic conversion of the cellular prion protein (PrP C ) into the pathologic isoform PrP Sc is a key feature in prion pathogenesis. AR-12 is an IND-approved derivative of celecoxib that demonstrated preclinical activity against several microbial diseases. Recently, AR-12 has been shown to facilitate clearance of misfolded proteins. The latter proposes AR-12 to be a potential therapeutic agent for neurodegenerative disorders. In this study, we investigated the role of AR-12 and its derivatives in controlling prion infection. We tested AR-12 in prion infected neuronal and non-neuronal cell lines. Immunoblotting and confocal microscopy results showed that AR-12 and its analogue AR-14 reduced PrP Sc levels after only 72 hours of treatment. Furthermore, infected cells were cured of PrP Sc after exposure of AR-12 or AR-14 for only two weeks. We partially attribute the influence of the AR compounds on prion propagation to autophagy stimulation, in line with our previous findings that drug-induced stimulation of autophagy has anti-prion effects in vitro and in vivo. Taken together, this study demonstrates that AR-12 and the AR-14 analogue are potential new therapeutic agents for prion diseases and possibly protein misfolding disorders involving prion-like mechanisms.

ArF short-pulse extraction studies. Final technical report, 18 September 1981-18 February 1983

International Nuclear Information System (INIS)

Mandl, A.

1983-02-01

The experimental apparatus including e-beam pulse diagnostics is discussed. The relative fluorescence and laser output for various gas mixtures is presented and the significant improvement in laser performance for Ne buffered mixtures, allowing scaling to high pressures and high Joules per liter, is discussed. The energy deposition measurements for Ar and Ne buffered mixtures are presented. Accurate deposition measurements are necessary for a meaningful measure of the laser output efficiency. Background absorption measurements important for accessing the scalability of the ArF system are presented. The sidelight suppression experiments are discussed and the laser efficiency measurements are shown. Finally, a discussion of the measurements with their implications for the ArF system is presented in the concluding section

Atmospheric pressure plasma produced inside a closed package by a dielectric barrier discharge in Ar/CO2 for bacterial inactivation of biological samples

International Nuclear Information System (INIS)

Chiper, A S; Chen, W; Stamate, E; Mejlholm, O; Dalgaard, P

2011-01-01

The generation and evaluation of a dielectric barrier discharge produced inside a closed package made of a commercially available packaging film and filled with gas mixtures of Ar/CO 2 at atmospheric pressure is reported. The discharge parameters were analysed by electrical measurements and optical emission spectroscopy in two modes of operation: trapped gas atmosphere and flowing gas atmosphere. Gas temperature was estimated using the OH(A-X) emission spectrum and the rotational temperature reached a saturation level after a few minutes of plasma running. The rotational temperature was almost three times higher in the Ar/CO 2 plasma compared with an Ar plasma. The efficiency of the produced plasma for the inactivation of bacteria on food inside the closed package was investigated.

High-resolution Auger spectroscopy on 79 MeV Ar5+, 89 MeV Ar6+, and 136 MeV Ar7+ ions after excitation by helium

International Nuclear Information System (INIS)

Schneider, T.

1988-01-01

In this thesis the atomic structure of highly excited Ar 6+ and Ar 7+ ions was studied. For this 79 MeV Ar 5+ , 89 MeV Ar 6+ , and 136 MeV Ar 7+ ions of a heavy ion accelerator were excited by a He gas target to autoionizing states and the Auger electrons emitted in the decay were measured in highly-resolving state. The spectra were taken under an observational angle of zero degree relative to the beam axis in order to minimize the kinematical broadening of the Auger lines. (orig./HSI) [de

NEW ACCURATE MEASUREMENT OF {sup 36}ArH{sup +} AND {sup 38}ArH{sup +} RO-VIBRATIONAL TRANSITIONS BY HIGH RESOLUTION IR ABSORPTION SPECTROSCOPY

Energy Technology Data Exchange (ETDEWEB)

Cueto, M.; Herrero, V. J.; Tanarro, I.; Doménech, J. L. [Molecular Physics Department, Instituto de Estructura de la Materia (IEM-CSIC), Serrano 123, E-28006 Madrid (Spain); Cernicharo, J. [Department of Astrophysics, CAB. INTA-CSIC. Crta Torrejón-Ajalvir Km 4, E-28850 Torrejón de Ardoz, Madrid (Spain); Barlow, M. J.; Swinyard, B. M., E-mail: jl.domenech@csic.es [Department of Physics and Astronomy, University College London. Gower Street, London WC1E 6BT (United Kingdom)

2014-03-01

The protonated argon ion, {sup 36}ArH{sup +}, was recently identified in the Crab Nebula from Herschel spectra. Given the atmospheric opacity at the frequency of its J = 1-0 and J = 2-1 rotational transitions (617.5 and 1234.6 GHz, respectively), and the current lack of appropriate space observatories after the recent end of the Herschel mission, future studies on this molecule will rely on mid-infrared observations. We report on accurate wavenumber measurements of {sup 36}ArH{sup +} and {sup 38}ArH{sup +} rotation-vibration transitions in the v = 1-0 band in the range 4.1-3.7 μm (2450-2715 cm{sup –1}). The wavenumbers of the R(0) transitions of the v = 1-0 band are 2612.50135 ± 0.00033 and 2610.70177 ± 0.00042 cm{sup –1} (±3σ) for {sup 36}ArH{sup +} and {sup 38}ArH{sup +}, respectively. The calculated opacity for a gas thermalized at a temperature of 100 K and with a linewidth of 1 km s{sup –1} of the R(0) line is 1.6 × 10{sup –15} × N({sup 36}ArH{sup +}). For column densities of {sup 36}ArH{sup +} larger than 1 × 10{sup 13} cm{sup –2}, significant absorption by the R(0) line can be expected against bright mid-IR sources.

Cross Sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl and 40Ar(d,p)41Ar Nuclear Reactions below 8.4 MeV

Science.gov (United States)

Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

2011-01-01

We have measured the cross section for production of the medically interesting isotope 34mCl, along with 38Cl and 41Ar, using deuteron bombardments of 36Ar and 40Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. PMID:22041299

40Ar/39Ar geochronology of the El Teniente porphyry copper deposit

International Nuclear Information System (INIS)

Maksaev, V; Munizaga, F; McWilliams, M; Thiele, K; Arevalo, A; Zuniga, P; Floody, R

2001-01-01

breccias. Phyllic alteration primarily occurs as quartz-sericite haloes of quartz-sulfide-sulfate veinlets within the perimeter of the orebody, and slightly overprints potassic alteration. Propylitic alteration occurs largely peripheral to ore-grade rock. The relatively restricted development of phyllic alteration and the occurrence of the central breccia conflict with the classic porphyry copper model of Lowell and Gilbert (1970), but El Teniente may be regarded as a 'variation on a theme' of the classic model, as suggested by Gustafson and Hunt (1975). The exceedingly large size of the El Teniente deposit, coupled with its apparently young mineralization age prompted us to initiate a systematic 40 Ar/ 39 Ar study whose goals are to determine the age(s) of the hydrothermal event(s) that produced such a remarkable copper concentration and ultimately to estimate the duration of the hydrothermal activity at El Teniente. This is particularly relevant to an understanding of the processes that formed super-giant high-grade copper deposits in the Chilean Andes and elsewhere. We report here 32 total fusion 40 Ar/ 39 Ar ages from sericite and biotite from different lithologic units of El Teniente and five step-heating 40 Ar- 39 Ar ages of samples previously dated using conventional K-Ar methods (Cuadra, 1986) (au)

Androgen Receptor Variant AR-V9 Is Coexpressed with AR-V7 in Prostate Cancer Metastases and Predicts Abiraterone Resistance.

Science.gov (United States)

Kohli, Manish; Ho, Yeung; Hillman, David W; Van Etten, Jamie L; Henzler, Christine; Yang, Rendong; Sperger, Jamie M; Li, Yingming; Tseng, Elizabeth; Hon, Ting; Clark, Tyson; Tan, Winston; Carlson, Rachel E; Wang, Liguo; Sicotte, Hugues; Thai, Ho; Jimenez, Rafael; Huang, Haojie; Vedell, Peter T; Eckloff, Bruce W; Quevedo, Jorge F; Pitot, Henry C; Costello, Brian A; Jen, Jin; Wieben, Eric D; Silverstein, Kevin A T; Lang, Joshua M; Wang, Liewei; Dehm, Scott M

2017-08-15

Purpose: Androgen receptor (AR) variant AR-V7 is a ligand-independent transcription factor that promotes prostate cancer resistance to AR-targeted therapies. Accordingly, efforts are under way to develop strategies for monitoring and inhibiting AR-V7 in castration-resistant prostate cancer (CRPC). The purpose of this study was to understand whether other AR variants may be coexpressed with AR-V7 and promote resistance to AR-targeted therapies. Experimental Design: We utilized complementary short- and long-read sequencing of intact AR mRNA isoforms to characterize AR expression in CRPC models. Coexpression of AR-V7 and AR-V9 mRNA in CRPC metastases and circulating tumor cells was assessed by RNA-seq and RT-PCR, respectively. Expression of AR-V9 protein in CRPC models was evaluated with polyclonal antisera. Multivariate analysis was performed to test whether AR variant mRNA expression in metastatic tissues was associated with a 12-week progression-free survival endpoint in a prospective clinical trial of 78 CRPC-stage patients initiating therapy with the androgen synthesis inhibitor, abiraterone acetate. Results: AR-V9 was frequently coexpressed with AR-V7. Both AR variant species were found to share a common 3' terminal cryptic exon, which rendered AR-V9 susceptible to experimental manipulations that were previously thought to target AR-V7 uniquely. AR-V9 promoted ligand-independent growth of prostate cancer cells. High AR-V9 mRNA expression in CRPC metastases was predictive of primary resistance to abiraterone acetate (HR = 4.0; 95% confidence interval, 1.31-12.2; P = 0.02). Conclusions: AR-V9 may be an important component of therapeutic resistance in CRPC. Clin Cancer Res; 23(16); 4704-15. ©2017 AACR . ©2017 American Association for Cancer Research.

Single-crystal 40Ar/39Ar incremental heating reveals bimodal sanidine ages in the Bishop Tuff

Science.gov (United States)

Andersen, N. L.; Jicha, B. R.; Singer, B. S.

2015-12-01

The 650 km3 Bishop Tuff (BT) is among the most studied volcanic deposits because it is an extensive marker bed deposited just after the Matuyama-Brunhes boundary. Reconstructions of the vast BT magma reservoir from which high-silica rhyolite erupted have long influenced thinking about how large silicic magma systems are assembled, crystallized, and mixed. Yet, the longevity of the high silica rhyolitic melt and exact timing of the eruption remain controversial due to recent conflicting 40Ar/39Ar sanidine vs. SIMS and ID-TIMS U-Pb zircon dates. We have undertaken 21 40Ar/39Ar incremental heating ages on 2 mm BT sanidine crystals from pumice in 3 widely separated outcrops of early-erupted fall and flow units. Plateau ages yield a bimodal distribution: a younger group has a mean of 766 ka and an older group gives a range between 772 and 782 ka. The younger population is concordant with the youngest ID-TIMS and SIMS U-Pb zircon ages recently published, as well as the astronomical age of BT in marine sediment. Of 21 crystals, 17 yield older, non-plateau, steps likely affected by excess Ar that would bias traditional 40Ar/39Ar total crystal fusion ages. The small spread in older sanidine ages, together with 25+ kyr of pre-eruptive zircon growth, suggest that the older sanidines are not partially outgassed xenocrysts. A bimodal 40Ar/39Ar age distribution implies that some fraction of rhyolitic melt cooled below the Ar closure temperature at least 10 ky prior to eruption. We propose that rapid "thawing" of a crystalline mush layer released older crystals into rhyolitic melt from which sanidine also nucleated and grew immediately prior to the eruption. High precision 40Ar/39Ar dating can thus provide essential information on thermo-physical processes at the millenial time scale that are critical to interpreting U-Pb zircon age distributions that are complicated by large uncertainties associated with zircon-melt U-Th systematics.

Molecular dynamics study of Ar flow and He flow inside carbon nanotube junction as a molecular nozzle and diffuser

Directory of Open Access Journals (Sweden)

Itsuo Hanasaki, Akihiro Nakatani and Hiroshi Kitagawa

2004-01-01

Full Text Available A carbon nanotube junction consists of two connected nanotubes with different diameters. It has been extensively investigated as a molecular electronic device since carbon nanotubes can be metallic and semiconductive, depending on their structure. However, a carbon nanotube junction can also be viewed as a nanoscale nozzle andv diffuser. Here, we focus on the nanotube junction from the perspective of an intersection between machine, material and device. We have conducted a molecular dynamics simulation of the molecular flow inside a modeled (12,12–(8,8 nanotube junction. A strong gravitational field and a periodic boundary condition are applied in the flow direction. We investigated dense-Ar flows and dense-He flows while controlling the temperature of the nanotube junction. The results show that Ar atoms tend to be near to the wall and the density of the Ar is higher in the wide (12,12 nanotube than in the narrow (8,8 nanotube, while it is lower in the wide tube when no flow occurs. The streaming velocities of both the Ar and the He are higher in the narrow nanotube than in the wide nanotube, but the velocity of the Ar is higher than the velocity of the He and the temperature of the flowing Ar is higher than the temperature of the He when the same magnitude of gravitational field is applied.

Cross sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl, and 40Ar(d,p)41Ar nuclear reactions below 8.4 MeV.

Science.gov (United States)

Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

2012-02-01

We have measured the cross section for production of the medically interesting isotope (34m)Cl, along with (38)Cl and (41)Ar, using deuteron bombardments of (36)Ar and (40)Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. Copyright © 2011 Elsevier Ltd. All rights reserved.

Classical treatment of Li2++Ar and He2++Ar collisions

International Nuclear Information System (INIS)

Jorge, A; Illescas, Clara; Pons, B

2015-01-01

Classical Trajectory Monte Carlo calculations are carried out for Li 2+ +Ar and He 2+ +Ar collisions, motivated by recent experiments on these systems. Cross sections for electron capture, projectile electron loss and target multiple ionization processes are evaluated and compared to the experimental values in the 75-500 keV/amy impact energy range. (paper)

40Ar/ 39Ar and paleomagnetic results from Liberia and the Precambrian APW data base for the West African Shield

Science.gov (United States)

Onstott, T. C.; Dorbor, J.

Lower amphibolite to granulite facies metamorphic rocks in Nimba County, Liberia have yielded 2.2-2.9 Ga RbSr whole rock ages, indicating that they are part of the Archean Liberian age province. We report a 2040 Ma 4040Ar/ 39Ar plateau date on hornblende from an amphibolite in this region, and suggest that these rocks were also severelyreworked during the Eburnean (˜2.0 Ga) metamorphic episode. 40Ar/ 39Ar analyses of biotite and feldspars from neighboring schists also indicate the presence of two mild thermal events, at 1.5 Ga and 0.6 Ga. Paleomagnetic analyses of samples from these same metamorphic rocks reveal three components of magnetization. The predominant and most stable component (273°E, 21°N) is considered to have been acquired as a result of pos Eburnean uplift and cooling at ˜ 2.0 Ga, whereas the two less stable components with poles at 235°E, 43°N and 16°E, 36°N, probably correlate with the 1.5 Ga and 0.6 Ga thermal pulses, respectively. Rock units from southern Liberia also yield two secondary magnetizations, one at 247°E, 37°N and the other at 104°E, 5°N, and a 1.5 Ga 40Ar/ 39Ar date on plagioclase. Comparison of the paleomagnetic poles corresponding to the ˜2.0 Ga Eburnean component with published paleomagnetic data for West Africa is not consistent with prior interpretations of the polar wander path for West Africa. Our paleomagnetic data, when compared to poles of comparable age from the Kalahari Shield, still suggest that some form of displacement has occurred between the Kalahari and West African Shields since 2.0 Ga.

Thermal significance of potassium feldspar K-Ar ages inferred from /sup 40/Ar//sup 39/Ar age spectrum results

Energy Technology Data Exchange (ETDEWEB)

Harrison, T.M.; McDougall, I. (Australian National Univ., Canberra. Research School of Earth Sciences)

1982-10-01

/sup 40/Ar//sup 39/Ar age spectrum analyses of three microcline separates from the Separation Point Batholith, northwest Nelson, New Zealand, which cooled slowly through the temperature zone of partial radiogenic /sup 40/Ar accumulation are characterized by a linear age increase over the first 65 percent of gas release with the lowest ages corresponding to the time that the samples cooled below about 100/sup 0/C. The last 35 percent of /sup 39/Ar released from the microclines yields plateau ages which reflect the different bulk mineral ages, and correspond to cooling temperatures between about 130 to 160/sup 0/C. Theoretical calculations confirm the likelihood of diffusion gradients in feldspars cooling at rates =< 5/sup 0/C-Ma/sup -1/. Diffusion parameters calculated from the /sup 39/Ar release yield an activation energy, E = 28.8 +- 1.9 kcal-mol/sup -1/, and a frequency factor/grain size parameter, D/sub 0//l/sup 2/ = 5.6sub(-3.9)sup(+14) sec/sup -1/. This Arrhenius relationship corresponds to a closure temperature of 132 +- 13/sup 0/C which is very similar to the independently estimated temperature. From the observed diffusion compensation correlation, this D/sub 0//l/sup 2/ implies an average diffusion half-width of about 3 ..mu..m, similar to the half-width of the perthite lamellae in the feldspars. The results are discussed.

40Ar-39Ar dating of hornfels dredged near the Japan trench

International Nuclear Information System (INIS)

Takigami, Yutaka; Fujioka, Kantaro

1989-01-01

During the KH 81-3 Cruise of the R/V Hakuho-Maru, biotite-bearing hornfelses were dredged from the landward slope of the Japan Trench. Bulk sample and separated biotite were dated by the 40 Ar- 39 Ar method and they showed 40 Ar- 39 Ar ages of 28.9±1.4 Ma and 28.5±1.4 Ma, respectively. This would indicate that biotite was formed at about 29 Ma by the thermal metamorphism which might have related with some magmatic activity. In this magmatic activity was caused by the subducting oceanic plate in the similar conditions at present, it seems to have occurred at a place too close to the present trench axis. This discrepancy could be explained by such processes as the change of the angle of the subducting plate, the moving of the trench axis by tectonic erosion and so on. However, more age data are required to solve this discrepancy. (author)

40Ar/39Ar and K/Ar whole rock age constraints on the timing of regional deformation, South Coast of New South Wales, Lachlan Fold Belt, Southeastern Australia: problems and implications

International Nuclear Information System (INIS)

Phillips, D.; Fergusson, C.L.

1999-01-01

Full text: Subduction complex rocks are well exposed on the south coast of New South Wales around Batemans Bay. Farther south in the Narooma and Bermagui region, Offier et al (1998) have determined two 40 Ar/ 39 Ar ages of 450 ± 3 Ma and 445 ± 2 Ma. They argued that these ages constrain the timing of intense underplating-related deformation and we have undertaken farther work, from an area south of Batemans Bay, to test this suggestion. The 40 Ar/ 39 Ar method applied to fine-grained, low temperature metamorphic rocks, such as slates, is beset by the problem of recoil loss and/or redistribution of 39 Ar during the irradiation process. Another problem is the difficulty of distinguishing between the contributions to 40 Ar/ 39 Ar spectra from illite/muscovite grown during the cleavage-producing deformation and detrital muscovite/illite. In the current study, four slate samples, with variable contents of detrital white mica, were analysed by both the K-Ar and 40 Ar/ 39 Ar step-heating methods. A separate of detrital white mica from one slate sample yields a plateau age of 500 ± 2 Ma. This result indicates that inheritance has not been eliminated by metamorphism as is commonly assumed and that the 40 Ar/ 39 Ar ages provide only a maximum estimate for the timing of deformation. 40 Ar/ 39 Ar analyses of state chips yield discordant, saddle-shaped age spectra, with minimum, within-saddle' ages of ca. 420 Ma. Two slate samples give identical 40 Ar/ 39 Ar integrated ages of 455 ± 2 Ma. One sample contains relatively abundant detrital bedding-parallel mica flakes that are locally oblique to the regional cleavage in the rock. The 40 Ar/ 39 Ar ages are some 20 Ma older than K-Ar ages for these same samples, suggesting that recoil loss of 39 Ar may also have affected these slates. Both recoil loss of 39 Ar and inherited white micas will yield elevated apparent ages, thus providing only maximum ages for the cleavage-producing deformation. Two other samples from slaty tectonic

Androgen Receptor (AR) Physiological Roles in Male and Female Reproductive Systems: Lessons Learned from AR-Knockout Mice Lacking AR in Selective Cells1

Science.gov (United States)

Chang, Chawnshang; Lee, Soo Ok; Wang, Ruey-Sheng; Yeh, Shuyuan; Chang, Ta-Min

2013-01-01

ABSTRACT Androgens/androgen receptor (AR) signaling is involved primarily in the development of male-specific phenotypes during embryogenesis, spermatogenesis, sexual behavior, and fertility during adult life. However, this signaling has also been shown to play an important role in development of female reproductive organs and their functions, such as ovarian folliculogenesis, embryonic implantation, and uterine and breast development. The establishment of the testicular feminization (Tfm) mouse model exploiting the X-linked Tfm mutation in mice has been a good in vivo tool for studying the human complete androgen insensitivity syndrome, but this mouse may not be the perfect in vivo model. Mouse models with various cell-specific AR knockout (ARKO) might allow us to study AR roles in individual types of cells in these male and female reproductive systems, although discrepancies are found in results between labs, probably due to using various Cre mice and/or knocking out AR in different AR domains. Nevertheless, no doubt exists that the continuous development of these ARKO mouse models and careful studies will provide information useful for understanding AR roles in reproductive systems of humans and may help us to develop more effective and more specific therapeutic approaches for reproductive system-related diseases. PMID:23782840

Prostate Cancer Cells Express More Androgen Receptor (AR) Following Androgen Deprivation, Improving Recognition by AR-Specific T Cells.

Science.gov (United States)

Olson, Brian M; Gamat, Melissa; Seliski, Joseph; Sawicki, Thomas; Jeffery, Justin; Ellis, Leigh; Drake, Charles G; Weichert, Jamey; McNeel, Douglas G

2017-12-01

Androgen deprivation is the primary therapy for recurrent prostate cancer, and agents targeting the androgen receptor (AR) pathway continue to be developed. Because androgen-deprivation therapy (ADT) has immmunostimulatory effects as well as direct antitumor effects, AR-targeted therapies have been combined with other anticancer therapies, including immunotherapies. Here, we sought to study whether an antigen-specific mechanism of resistance to ADT (overexpression of the AR) may result in enhanced AR-specific T-cell immune recognition, and whether this might be strategically combined with an antitumor vaccine targeting the AR. Androgen deprivation increased AR expression in human and murine prostate tumor cells in vitro and in vivo The increased expression persisted over time. Increased AR expression was associated with recognition and cytolytic activity by AR-specific T cells. Furthermore, ADT combined with vaccination, specifically a DNA vaccine encoding the ligand-binding domain of the AR, led to improved antitumor responses as measured by tumor volumes and delays in the emergence of castrate-resistant prostate tumors in two murine prostate cancer models (Myc-CaP and prostate-specific PTEN-deficient mice). Together, these data suggest that ADT combined with AR-directed immunotherapy targets a major mechanism of resistance, overexpression of the AR. This combination may be more effective than ADT combined with other immunotherapeutic approaches. Cancer Immunol Res; 5(12); 1074-85. ©2017 AACR . ©2017 American Association for Cancer Research.

The 40Ar/39Ar and U/Pb dating of young rhyolites in the Kos-Nisyros volcanic complex, Eastern Aegean Arc, Greece: Age discordance due to excess 40Ar in biotite

Science.gov (United States)

Bachmann, O.; Schoene, B.; Schnyder, C.; Spikings, R.

2010-08-01

High-precision dating of Quaternary silicic magmas in the active Kos-Nisyros volcanic center (Aegean Arc, Greece) by both 40Ar/39Ar on biotite and U/Pb on zircon reveals a complex geochronological story. U/Pb ID-TIMS multi and single-grain zircon analyses from 3 different units (Agios Mammas and Zini domes, Kefalos Serie pyroclasts) range in age from 0.3 to 0.5 to 10-20 Ma. The youngest dates provide the maximum eruption age, while the oldest zircons indicate inheritance from local continental crust (Miocene and older). Step-heating 40Ar/39Ar experiments on 1-3 crystals of fresh biotite yielded highly disturbed Ar-release patterns with plateau ages typically older than most U/Pb ages. These old plateau ages are probably not a consequence of inheritance from xenocrystic biotites because Ar diffuses extremely fast at magmatic temperatures and ratios are reset within a few days. On the basis of (1) elevated and/or imprecise 40Ar/36Ar ratios, (2) shapes of the Ar release spectra, and (3) a high mantle 3He flux in the Kos-Nisyros area, we suggest that biotite crystals retained some mantle 40Ar that led to the observed, anomalously old ages. In contrast, sanidine crystals from the only sanidine-bearing unit in the Kos-Nisyros volcanic center (the caldera-forming Kos Plateau Tuff) do not appear to store any excess 40Ar relative to atmospheric composition. The eastern edge of the Aegean Arc is tectonically complex, undergoing rapid extension and located close to a major structural boundary. In such regions, which are characterized by high fluxes of mantle volatiles, 40Ar/39Ar geochronology on biotite can lead to erroneous results due to the presence of excess 40Ar and should be checked either against 40Ar/39Ar sanidine or U/Pb zircon ages.

The ChArMEx database

Science.gov (United States)

Ferré, Hélène; Descloitres, Jacques; Fleury, Laurence; Boichard, Jean-Luc; Brissebrat, Guillaume; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

2013-04-01

(SEVIRI, TRIMM, PARASOL...) stored in the ICARE data archive using OpeNDAP protocole The website will soon propose new facilities. In particular, many in situ datasets will be homogenized and inserted in a relational database, in order to enable more accurate data selection and download of different datasets in a shared format. In order to meet the operational needs of the airborne and ground based observational teams during the ChArMEx 2012 pre-campaign and the 2013 experiment, a day-to-day quick look and report display website has been developed too: http://choc.sedoo.org. It offers a convenient way to browse weather conditions and chemical composition during the campaign periods.

Multimodal actions of the phytochemical sulforaphane suppress both AR and AR-V7 in 22Rv1 cells: Advocating a potent pharmaceutical combination against castration-resistant prostate cancer.

Science.gov (United States)

Khurana, Namrata; Kim, Hogyoung; Chandra, Partha K; Talwar, Sudha; Sharma, Pankaj; Abdel-Mageed, Asim B; Sikka, Suresh C; Mondal, Debasis

2017-11-01

Prostate cancer (PCa) cells expressing full-length androgen receptor (AR-FL) are susceptible to androgen deprivation therapy (ADT). However, outgrowth of castration-resistant prostate cancer (CRPC) can occur due to the expression of constitutively active (ligand-independent) AR splice variants, particularly AR-V7. We previously demonstrated that sulforaphane (SFN), an isothiocyanate phytochemical, can decrease AR-FL levels in the PCa cell lines, LNCaP and C4-2B. Here, we examined the efficacy of SFN in targeting both AR-FL and AR-V7 in the CRPC cell line, CWR22Rv1 (22Rv1). MTT cell viability, wound-heal assay, and colony forming unit (CFU) measurements revealed that 22Rv1 cells are resistant to the anti-androgen, enzalutamide (ENZ). However, co-exposure to SFN sensitized these cells to the potent anticancer effects of ENZ (PAR-FL and AR-V7 levels, and immunofluorescence microscopy (IFM) depicted decreased AR in both cytoplasm and nucleus with SFN treatment. SFN increased both ubiquitination and proteasomal activity in 22Rv1 cells. Studies using a protein synthesis inhibitor (cycloheximide) or a proteasomal inhibitor (MG132) indicated that SFN increases both ubiquitin-mediated aggregation and subsequent proteasomal-degradation of AR proteins. Previous studies reported that SFN inhibits the chaperone activity of heat-shock protein 90 (Hsp90) and induces the nuclear factor erythroid-2-like 2 (Nrf2) transcription factor. Therefore, we investigated whether the Hsp90 inhibitor, ganetespib (G) or the Nrf2 activator, bardoxolone methyl (BM) can similarly suppress AR levels in 22Rv1 cells. Low doses of G and BM, alone or in combination, decreased both AR-FL and AR-V7 levels, and combined exposure to G+BM sensitized 22Rv1 cells to ENZ. Therefore, adjunct treatment with the phytochemical SFN or a safe pharmaceutical combination of G+BM may be effective against CRPC cells, especially those expressing AR-V7.

40Ar/ 39Ar ages and paleomagnetism of São Miguel lavas, Azores

Science.gov (United States)

Johnson, Catherine L.; Wijbrans, Jan R.; Constable, Catherine G.; Gee, Jeff; Staudigel, Hubert; Tauxe, Lisa; Forjaz, Victor-H.; Salgueiro, Mário

1998-08-01

We present new 40Ar/ 39Ar ages and paleomagnetic data for São Miguel island, Azores. Paleomagnetic samples were obtained for 34 flows and one dike; successful mean paleomagnetic directions were obtained for 28 of these 35 sites. 40Ar/ 39Ar age determinations on 12 flows from the Nordeste complex were attempted successfully: ages obtained are between 0.78 Ma and 0.88 Ma, in contrast to published K-Ar ages of 1 Ma to 4 Ma. Our radiometric ages are consistent with the reverse polarity paleomagnetic field directions, and indicate that the entire exposed part of the Nordeste complex is of a late Matuyama age. The duration of volcanism across São Miguel is significantly less than previously believed, which has important implications for regional melt generation processes, and temporal sampling of the geomagnetic field. Observed stable isotope and trace element trends across the island can be explained, at least in part, by communication between different magma source regions at depth. The 40Ar/ 39Ar ages indicate that our normal polarity paleomagnetic data sample at least 0.1 Myr (0-0.1 Ma) and up to 0.78 Myr (0-0.78 Ma) of paleosecular variation and our reverse polarity data sample approximately 0.1 Myr (0.78-0.88 Ma) of paleosecular variation. Our results demonstrate that precise radiometric dating of numerous flows sampled is essential to accurate inferences of long-term geomagnetic field behavior. Negative inclination anomalies are observed for both the normal and reverse polarity time-averaged field. Within the data uncertainties, normal and reverse polarity field directions are antipodal, but the reverse polarity field shows a significant deviation from a geocentric axial dipole direction.

Towards a Sustainability Reporting Guideline in Higher Education

Science.gov (United States)

Huber, Sandra; Bassen, Alexander

2018-01-01

Purpose: So far, sustainability reporting in higher education is in a very early stage--partly, because of the lack of an established and widely recognized sustainability reporting framework for higher education institutions (HEIs). Therefore, a modification of the sustainability code for the use in the higher education context was recently…

Application of quadrupole mass spectrometer to the 40Ar-39Ar geochronological study

International Nuclear Information System (INIS)

Takigami, Yutaka; Nishijima, Tadashi; Koike, Toshio; Okuma, Kouichi.

1984-01-01

A Quadrupole Mass Spectrometer (QMS) has commonly been used for qualitative analyses of gases in organic chemistry or for monitoring the vacuum conditions in industrial machines. No attempt has been made, however, to apply it to geochronological studies because of its disadvantages such as the difficulty in obtaining precise isotope ratios due to triangular peak shapes and poor reproducibility. On the other hand, there are advantages that a QMS is relatively inexpensive and gives a shorter scanning time for analysis compared with a sector type mass spectrometer. The latter characteristics is useful for 40 Ar/ 39 Ar geochronological studies, since it gives a lower background in the QMS and the possibility to obtain many more data from one sample in a limited time. In this study, we have tried to improve a commercial QMS at many parts, such as rf-generator, quadrupole, ionization chamber, source magnet, and so on, in order to meet the requirements to use it for geochronological studies. With the use of the improved QMS equipped with an on-line microcomputer, we could obtain Ar isotope data which are sufficiently precise for the 40 Ar/ 39 Ar geochronological studies. (author)

ARS-Media for excel instruction manual

Science.gov (United States)

ARS-Media for Excel Instruction Manual is the instruction manual that explains how to use the Excel spreadsheet ARS-Media for Excel application. ARS-Media for Excel Instruction Manual is provided as a pdf file....

The thermal history of the Lhasa Block, South Tibetan Plateau based on FTD and Ar-Ar dating

CERN Document Server

Yang, T F; Lo Chong Huah; Chung, S L; Tien, R L; Xu, R; Deng, W

1999-01-01

Twelve basement samples were collected from South Tibet Plateau for FTD and Ar-Ar analysis to demonstrate their uplifting history since Cenozoic era. The preliminary results from different minerals with different closure temperatures, including apatite and zircon for fission-track dating, and K-feldspar, biotite for Ar-Ar dating, show that at least four stages of thermal history can be recognized in the studied area.

The thermal history of the Lhasa Block, South Tibetan Plateau based on FTD and Ar-Ar dating

International Nuclear Information System (INIS)

Yang, T.F.; Wang, J.R.; Lo, C.H.; Chung, S.L.; Tien, R.L.; Xu, R.; Deng, W.

1999-01-01

Twelve basement samples were collected from South Tibet Plateau for FTD and Ar-Ar analysis to demonstrate their uplifting history since Cenozoic era. The preliminary results from different minerals with different closure temperatures, including apatite and zircon for fission-track dating, and K-feldspar, biotite for Ar-Ar dating, show that at least four stages of thermal history can be recognized in the studied area

The Long Non-Coding RNA XIST Interacted with MiR-124 to Modulate Bladder Cancer Growth, Invasion and Migration by Targeting Androgen Receptor (AR).

Science.gov (United States)

Xiong, Yaoyao; Wang, Long; Li, Yuan; Chen, Minfeng; He, Wei; Qi, Lin

2017-01-01

Long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) is involved in the progression of several tumors. The interaction between lncRNA and miRNA or miRNA's target genes is reported to play crucial roles in malignancy. In addition, Androgen receptor (AR) is considered to be involved in bladder cancer progression. In this study, we investigated the role of XIST in human bladder cancer and its interaction with miR-124 and AR. XIST and AR expression was detected in bladder tumor samples and cell lines. Effects of XIST and AR on bladder cancer cells growth, invasion and migration were analyzed. Bioinformatic analysis and luciferase assays were used to identify the interaction among XIST, AR and miR-124. The correlations of miR-124 with XIST and AR in bladder cancer samples were statistically analyzed. XIST and AR were upregulated in bladder cancer tissues and positively correlated. Higher XIST and AR expression were related to poorer TNM stage of bladder cancer. XIST knockdown reduced bladder cancer cells' proliferation, invasion and migration. While this inhibitory effect could be partially restored by AR overexpression. XIST inhibited miR-124 expression by directly targeting. Moreover, miR-124 could bind to the 3'UTR of AR to regulate its expression. MiR-124 inhibition partially restored the XIST knockdown-induced reduction of AR, c-myc, p27, MMP13 and MMP9 expression. In bladder cancer tissues, miR-124 level was inversely correlated with the expression of XIST and AR, respectively. These findings indicated that XIST might be an oncogenic lncRNA that promoted the bladder cancer growth, invasion and migration via miR-124 dependent AR regulation. © 2017 The Author(s). Published by S. Karger AG, Basel.

The Long Non-Coding RNA XIST Interacted with MiR-124 to Modulate Bladder Cancer Growth, Invasion and Migration by Targeting Androgen Receptor (AR

Directory of Open Access Journals (Sweden)

Yaoyao Xiong

2017-08-01

Full Text Available Backgrounds/Aims: Long non-coding RNA (lncRNA X-inactive specific transcript (XIST is involved in the progression of several tumors. The interaction between lncRNA and miRNA or miRNA’s target genes is reported to play crucial roles in malignancy. In addition, Androgen receptor (AR is considered to be involved in bladder cancer progression. In this study, we investigated the role of XIST in human bladder cancer and its interaction with miR-124 and AR. Methods: XIST and AR expression was detected in bladder tumor samples and cell lines. Effects of XIST and AR on bladder cancer cells growth, invasion and migration were analyzed. Bioinformatic analysis and luciferase assays were used to identify the interaction among XIST, AR and miR-124. The correlations of miR-124 with XIST and AR in bladder cancer samples were statistically analyzed. Results: XIST and AR were upregulated in bladder cancer tissues and positively correlated. Higher XIST and AR expression were related to poorer TNM stage of bladder cancer. XIST knockdown reduced bladder cancer cells’ proliferation, invasion and migration. While this inhibitory effect could be partially restored by AR overexpression. XIST inhibited miR-124 expression by directly targeting. Moreover, miR-124 could bind to the 3’UTR of AR to regulate its expression. MiR-124 inhibition partially restored the XIST knockdown-induced reduction of AR, c-myc, p27, MMP13 and MMP9 expression. In bladder cancer tissues, miR-124 level was inversely correlated with the expression of XIST and AR, respectively. Conclusion: These findings indicated that XIST might be an oncogenic lncRNA that promoted the bladder cancer growth, invasion and migration via miR-124 dependent AR regulation.

The role of the AR/ER ratio in ER-positive breast cancer patients.

Science.gov (United States)

Rangel, Nelson; Rondon-Lagos, Milena; Annaratone, Laura; Osella-Abate, Simona; Metovic, Jasna; Mano, Maria Piera; Bertero, Luca; Cassoni, Paola; Sapino, Anna; Castellano, Isabella

2018-03-01

The significance of androgen receptor (AR) in breast cancer (BC) management is not fully defined, and it is still ambiguous how the level of AR expression influences oestrogen receptor-positive (ER+) tumours. The aim of the present study was to analyse the prognostic impact of AR/ER ratio, evaluated by immunohistochemistry (IHC), correlating this value with clinical, pathological and molecular characteristics. We retrospectively selected a cohort of 402 ER+BC patients. On each tumour, IHC analyses for AR, ER, PgR, HER2 and Ki67 were performed and AR+ cases were used to calculate the AR/ER value. A cut-off of ≥2 was selected using receiver-operating characteristic (ROC) curve analyses. RNA from 19 cases with AR/ER≥2 was extracted and used for Prosigna-PAM50 assays. Tumours with AR/ER≥2 (6%) showed more frequent metastatic lymph nodes, larger size, higher histological grade and lower PgR levels than cases with AR/ERAR/ER≥2 had worse disease-free interval (DFI) and disease-specific survival (DSS) (hazard ratios (HR) = 4.96 for DFI and HR = 8.69 for DSS, both P  ≤ 0.004). According to the Prosigna-PAM50 assay, 63% (12/19) of these cases resulted in intermediate or high risk of recurrence categories. Additionally, although all samples were positive for ER assessed by IHC, the molecular test assigned 47.4% (9/19) of BCs to intrinsic non-luminal subtypes. In conclusion, the AR/ER ratio ≥2 identifies a subgroup of patients with aggressive biological features and may represent an additional independent marker of worse BC prognosis. Moreover, the Prosigna-PAM50 results indicate that a significant number of cases with AR/ER≥2 could be non-luminal tumours. © 2018 Society for Endocrinology.

Ar-Xe Laser: The Path to a Robust, All-Electric Shipboard Directed Energy Weapon

National Research Council Canada - National Science Library

Apruzese, J. P; Sethian, J. D; Giuliani, J. L; Wolford, M. F

2008-01-01

.... The electron beam pumped Ar-Xe laser has been investigated in an ONR-sponsored 6.1 program at NRL. The results of this program are summarized in this Memorandum Report, and indicate that the Ar-Xe laser has strong potential to meet these requirements...

High-resolution 40Ar/39Ar chronology of multiple intrusion igneous complexes

Science.gov (United States)

Foland, K. A.; Chen, J.-F.; Linder, J. S.; Henderson, C. M. B.; Whillans, I. M.

1989-06-01

The Mount Brome complex of the Monteregian province of southern Quebec, Canada, consits of several major intrusions ranging compositionally from gabbro to syenite. The relative ages of these intrusives have been investigated with high-resolution 40Ar/39Ar analyses, including a specially designed irradiation configuration to cancel the effects of fluence gradients. Small yet distinct apparent age differences are observed. While a number of analytical and geological factors could be proposed to explain the small variations, evaluation of these suggests the age differences reflect those in emplacement times. The gabbro and nepheline diorite were emplaced within a short span 123.1 Ma ago. Generally more evolved lithologies (biotite monzodiorite, pulaskite, nordmarkite) appear to have been emplaced within a restricted interval 1.4±0.3 Ma later. Whole-rock Rb-Sr systematics do not give acceptable isochrons because of significant scatter interpreted to reflect initial 87Sr/86Sr heterogeneities resulting from crustal contamination. Considering the variations in initial ratio, the Rb-Sr data are consistent with the 40Ar/39Ar age.

Backbendings of superdeformed bands in 36;40Ar

Science.gov (United States)

Xiang, Xu-Hui; He, Xiao-Tao

2018-05-01

Experimentally observed superdeformed (SD) rotational bands in 36Ar and 40Ar are studied by the cranked shell model (CSM) with the pairing correlations treated by a particle-number-conserving (PNC) method. This is the first time that PNC-CSM calculations have been performed on the light nuclear mass region around A=40. The experimental kinematic moments of inertia J (1) versus rotational frequency are reproduced well. The backbending of the SD band at frequency around ℏω=1.5 MeV in 36Ar is attributed to the sharp rise of the simultaneous alignments of the neutron and proton 1d 5/2[202]5/2 pairs and 1f 7/2[321]3/2 pairs, which is a consequence of the band crossing between the 1d 5/2[202]5/2 and 1f 7/2[321]3/2 configuration states. The gentle upbending at low frequency of the SD band in 40Ar is mainly affected by the alignments of the neutron 1f 7/2[321]3/2 pairs and proton 1d 5/2[202]5/2 pairs. The PNC-CSM calculations show that besides the diagonal parts, the off-diagonal parts of the alignments play an important role in the rotational behavior of the SD bands. Supported by National Natural Science Foundation of China (11775112 and 11275098) and the Priority Academic Program Development of Jiangsu Higher Education Institutions

Postcollision interactions in the Auger decay of the Ar L-shell

Energy Technology Data Exchange (ETDEWEB)

Samson, J.A.R.; Stolte, W.C.; He, Z.X. [Univ. of Nebraska, Lincoln, NE (United States)] [and others

1997-04-01

The photoionization cross sections for Ar{sup +} through Ar{sup 4+}, produced by the Auger decay of an inner shell 2p hole, have been measured between 242 eV and 253 eV on beamline 9.0.1 and 6.3.2. In this study the authors are interested in near threshold phenomenon involving postcollision interactions (PCI), which are related to the Auger decay of a vacancy in the Ar L-shell. During an Auger decay a postcollision interaction can occur causing the out-going photoelectron to be retarded thus losing a certain amount of energy. If the retardation is sufficiently large the photoelectron will not escape. This result produces a singly charged ion, which normally would not be present. Such evidence of electron capture by the PCI effect was first shown clearly by Eberhardt et al. and, with higher resolution, in the present work. However, capture of the photoelectron is expected to be 100% exactly at the L{sub 2,3} thresholds. Thus, from the authors results they would have expected the Ar{sup 2+} signal to be zero at threshold, but it was not? The authors can explain this anomoly on the basis that during the Auger decay the photoelectrons are captured into high lying excited states of Ar{sup +}, which subsequently decay through autoionization yielding Ar{sup 2+}. Future work in this area will seek experimental evidence to verify this prediction.

Call for Development of New Mineral Standards for 40Ar/39Ar Dating

Science.gov (United States)

Deino, A. L.; Turrin, B. D.; Renne, P. R.; Hemming, S. R.

2015-12-01

Age determination via the 40Ar/39Ar dating method relies on the intercomparison of measured 40Ar*/39ArK ratios of geological unknowns with those of co-irradiated mineral standards. Good analytical procedure dictates that these ratios (and the evolution of the Ar ion beams underpinning them) be as similar as practical for the greatest accuracy. Unfortunately, throughout several intervals of the geological time scale this 'best practice' cannot be achieved with existing widely used standards. Only two internationally utilized sanidine standards are available for the middle to late Cenozoic: the Alder Creek Rhyolite sanidine (ACs), at ~1.2 Ma (Turrin et al., 1994; Nomade et al., 2005), and the Fish Canyon Tuff sanidine (FCs) at ~28.2 Ma (e.g., Kuiper et al., 2008; Renne et al, 2011). The situation is even worse throughout much of the rest of the Phanerozoic, as the next oldest standard in common use is the Hb3gr hornblende standard with an age of ~1.1 Ga (Turner, 1971; Jourdan et al., 2006). We propose, as a community effort, the development a set of standards covering the entire target range of high-precision 40Ar/39Ar dating, i.e. the Phanerozoic. Their ages would be stepped in a regular fashion with no more than approximately a factor of 3 between standards, such that in the worse case the 40Ar*/39Ar ratios of standards and unknown need differ by no more than a factor of two. While somewhat arbitrary, an approximately 3 X age progression allows the entire time scale to be covered by a manageable number of standards. Anchoring the progression in the widely used ACs, FCs, and Hb3gr (in bold, below) yields the following set of suggested standard ages: 0.4, 1.2, 3.3, 9.4, 28.2, 95, 320, and 1100 Ma. A suitable standard should be highly reproducible in age at the grain-to-grain and sub-grain levels, and highly radiogenic. The mineral should be abundant and easily separated from the host rock. These criteria may be most easily achieved by focusing on sanidine phenocrysts

Bacillus sp.CDB3 isolated from cattle dip-sites possesses two ars gene clusters

Institute of Scientific and Technical Information of China (English)

Somanath Bhat; Xi Luo; Zhiqiang Xu; Lixia Liu; Ren Zhang

2011-01-01

Contamination of soil and water by arsenic is a global problem.In Australia, the dipping of cattle in arsenic-containing solution to control cattle ticks in last centenary has left many sites heavily contaminated with arsenic and other toxicants.We had previously isolated five soil bacterial strains (CDB1-5) highly resistant to arsenic.To understand the resistance mechanism, molecular studies have been carried out.Two chromosome-encoded arsenic resistance (ars) gene clusters have been cloned from CDB3 (Bacillus sp.).They both function in Escherichia coli and cluster 1 exerts a much higher resistance to the toxic metalloid.Cluster 2 is smaller possessing four open reading frames (ORFs) arsRorf2BC, similar to that identified in Bacillus subtilis Skin element.Among the eight ORFs in cluster 1 five are analogs of common ars genes found in other bacteria, however, organized in a unique order arsRBCDA instead of arsRDABC.Three other putative genes are located directly downstream and designated as arsTIP based on the homologies of their theoretical translation sequences respectively to thioredoxin reductases, iron-sulphur cluster proteins and protein phosphatases.The latter two are novel of any known ars operons.The arsD gene from Bacillus species was cloned for the first time and the predict protein differs from the well studied E.coli ArsD by lacking two pairs of C-terrninal cysteine residues.Its functional involvement in arsenic resistance has been confirmed by a deletion experiment.There exists also an inverted repeat in the intergenic region between arsC and arsD implying some unknown transcription regulation.

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

Science.gov (United States)

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

2018-01-01

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

Skolotāju uztvertā stresa saistība ar apmierinātību ar darbu

OpenAIRE

Dejus, Ilze

2014-01-01

Pētījuma „Skolotāju uztvertā stresa saistība ar apmierinātību ar darbu” mērķis, pamatojoties uz teorētisko analīzi, pētīt skolotāju uztvertā stresa saistību ar apmierinātību ar darbu. Pētījuma jautājumi: 1.Vai pastāv statistiski nozīmīga saistība starp skolotāju uztvertā stresa līmeni un apmierinātību ar darbu? 2.Vai pastāv statistiski nozīmīgas atšķirības starp Liepājas 15.vidusskolas un Grobiņas novada skolotāju uztvertā stresa līmeni un apmierinātību ar darbu? Aptaujāti 113 skolot...

Androgen-Sensitized Apoptosis of HPr-1AR Human Prostate Epithelial Cells.

Directory of Open Access Journals (Sweden)

Congcong Chen

Full Text Available Androgen receptor (AR signaling is crucial to the development and homeostasis of the prostate gland, and its dysregulation mediates common prostate pathologies. The mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells have been investigated in human and rodent adult prostate. However, the cellular stress response of human prostate epithelial cells is not well understood, though it is central to prostate health and pathology. Here, we report that androgen sensitizes HPr-1AR and RWPE-AR human prostate epithelial cells to cell stress agents and apoptotic cell death. Although 5α-dihydrotestosterone (DHT treatment alone did not induce cell death, co-treatment of HPr-1AR cells with DHT and an apoptosis inducer, such as staurosporine (STS, TNFt, or hydrogen peroxide, synergistically increased cell death in comparison to treatment with each apoptosis inducer by itself. We found that the synergy between DHT and apoptosis inducer led to activation of the intrinsic/mitochondrial apoptotic pathway, which is supported by robust cleavage activation of caspase-9 and caspase-3. Further, the dramatic depolarization of the mitochondrial membrane potential that we observed upon co-treatment with DHT and STS is consistent with increased mitochondrial outer membrane permeabilization (MOMP in the pro-apoptotic mechanism. Interestingly, the synergy between DHT and apoptosis inducer was abolished by AR antagonists and inhibitors of transcription and protein synthesis, suggesting that AR mediates pro-apoptotic synergy through transcriptional regulation of MOMP genes. Expression analysis revealed that pro-apoptotic genes (BCL2L11/BIM and AIFM2 were DHT-induced, whereas pro-survival genes (BCL2L1/BCL-XL and MCL1 were DHT-repressed. Hence, we propose that the net effect of these AR-mediated expression changes shifts the balance of BCL2-family proteins

Precision angle-resolved autoionization resonances in Ar and Ne

Energy Technology Data Exchange (ETDEWEB)

Berrah, N.; Langer, B.; Gorczyca, T.W. [Western Michigan Univ., Kalamazoo, MI (United States)] [and others

1997-04-01

Theoretical work has shown that the electron angular distribution and the shape of the autoionization resonances are crucial to the understanding of certain types of electron-electron correlation. Autoionization resonances in Ne (Ar) result from the decay of the excited discrete state Ne{sup *} 2s2p{sup 6} np (Ar{sup *} 3s3p{sup 6} np) into the continuum state Ne{sup +} 2s{sup 2}2p{sup 5} + e{sup {minus}} (ks,kd) (Ar{sup +} 3s{sup 2}3p{sup 5} + e{sup {minus}} (ks,kd)). Since the continuum can also be reached by direct photoionization, both paths add coherently, giving rise to interferences that produce the characteristic Beutler-Fano line shape. In this work, the authors report on quantitative angle-resolved electron spectrometry studies of (a) the Ne 2s{sup 2}2p{sup 6} {r_arrow} 2s2p{sup 6} np (n=3-5) autoionizing resonances and the 2s{sup 2}2p{sup 6} {r_arrow} 2p{sup 4}3s3p doubly excited resonance, (b) the Ar 3s{sup 2}3p{sup 6} {r_arrow} 3s3p{sup 6} np (n=4-9) autoionization resonances and extended R-matrix calculations of the angular-distribution parameters for both Ne and Ar measurements. Their results are compared with previous theoretical work by Taylor.

The ChArMEx database

Science.gov (United States)

Ferré, Helene; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

2014-05-01

observations or products that will be provided to the database. - A search tool to browse the catalogue using thematic, geographic and/or temporal criteria. - A shopping-cart web interface to order in situ data files. - A web interface to select and access to homogenized datasets. Interoperability between the two data centres is being set up using the OPEnDAP protocol. The data portal will soon propose a user-friendly access to satellite products managed by the ICARE data centre (SEVIRI, TRIMM, PARASOL...). In order to meet the operational needs of the airborne and ground based observational teams during the ChArMEx 2012 and 2013 campaigns, a day-to-day chart and report display website has been developed too: http://choc.sedoo.org. It offers a convenient way to browse weather conditions and chemical composition during the campaign periods.

Combined U-Th/He and 40Ar/39Ar geochronology of post-shield lavas from the Mauna Kea and Kohala volcanoes, Hawaii

Energy Technology Data Exchange (ETDEWEB)

Aciego, S.M.; Jourdan, F.; DePaolo, D.J.; Kennedy, B.M.; Renne, P.R.; Sims, K.W.W.

2009-10-01

Late Quaternary, post-shield lavas from the Mauna Kea and Kohala volcanoes on the Big Island of Hawaii have been dated using the {sup 40}Ar/{sup 39}Ar and U-Th/He methods. The objective of the study is to compare the recently demonstrated U-Th/He age method, which uses basaltic olivine phenocrysts, with {sup 40}Ar/{sup 39}Ar ages measured on groundmass from the same samples. As a corollary, the age data also increase the precision of the chronology of volcanism on the Big Island. For the U-Th/He ages, U, Th and He concentrations and isotopes were measured to account for U-series disequilibrium and initial He. Single analyses U-Th/He ages for Hamakua lavas from Mauna Kea are 87 {+-} 40 ka to 119 {+-} 23 ka (2{sigma} uncertainties), which are in general equal to or younger than {sup 40}Ar/{sup 39}Ar ages. Basalt from the Polulu sequence on Kohala gives a U-Th/He age of 354 {+-} 54 ka and a {sup 40}Ar/{sup 39}Ar age of 450 {+-} 40 ka. All of the U-Th/He ages, and all but one spurious {sup 40}Ar/{sup 39}Ar ages conform to the previously proposed stratigraphy and published {sup 14}C and K-Ar ages. The ages also compare favorably to U-Th whole rock-olivine ages calculated from {sup 238}U - {sup 230}Th disequilibria. The U-Th/He and {sup 40}Ar/{sup 39}Ar results agree best where there is a relatively large amount of radiogenic {sup 40}Ar (>10%), and where the {sup 40}Ar/{sup 36}Ar intercept calculated from the Ar isochron diagram is close to the atmospheric value. In two cases, it is not clear why U-Th/He and {sup 40}Ar/{sup 39}Ar ages do not agree within uncertainty. U-Th/He and {sup 40}Ar/{sup 39}Ar results diverge the most on a low-K transitional tholeiitic basalt with abundant olivine. For the most alkalic basalts with negligible olivine phenocrysts, U-Th/He ages were unattainable while {sup 40}Ar/{sup 39}Ar results provide good precision even on ages as low as 19 {+-} 4 ka. Hence, the strengths and weaknesses of the U-Th/He and {sup 40}Ar/{sup 39}Ar methods are

The mass of sup 3 sup 2 Ar and sup 3 sup 3 Ar for fundamental tests

CERN Document Server

Blaum, K; Beck, D; Bollen, G; Herfurth, F; Kellerbauer, A G; Kluge, H J; Sauvan, E; Schwarz, S

2003-01-01

Masses of the short-lived radionuclides sup 3 sup 2 Ar (T sub 1 sub / sub 2 = 98 ms) sup 3 sup 3 Ar (T sub 1 sub / sub 2 = 173 ms) have been determined with the Penning trap mass spectrometer ISOLTRAP. Relative uncertainties of 6.0 x 10 sup - sup 8 (delta m = 1.8 keV) and 1.4 x 10 sup - sup 8 (delta m = 0.44 keV), respectively, have been achieved. At present, these new mass data serve as the most stringent test of the quadratic form of the isobaricmultiplet mass equation IMME. Furthermore, the improved accuracy for the mass of sup 3 sup 2 Ar yields a better constraint on scalar contributions to the weak interaction. New mass values have also been measured for sup 4 sup 4 Ar and sup 4 sup 5 Ar, and a 20 sigma deviation for sup 4 sup 4 Ar from the literature value was found and interpreted.

Design analysis report for the 244-AR vault Interim Stabilization interior transfer system

International Nuclear Information System (INIS)

CARLSON, A.B.

2002-01-01

The purpose of this calculation note is to verify that the 244-AR Vault Interior Transfer System piping installed in the vault meets ASME B31.3 code requirements. This calculation also evaluates the pipe support loads

Ars Baltica-verkoston puheenjohtajuus Suomeen Risto Ruohoselle

Index Scriptorium Estoniae

1999-01-01

1990. a. loodud võrgustiku Ars Baltica sekretariaat (Ars Baltica Contact Point & Communication Center) tuleb Kielist Tallinnasse Eesti kultuuriministeeriumi kuni aastani 2002 (Suur-Karja 23). Ars Baltica (ühendus)

In-situ 40Ar/39Ar Laser Probe Dating of Micas from Mae Ping Shear Zone, Northern Thailand

Science.gov (United States)

Lin, Y. L.; Yeh, M. W.; Lo, C. H.; Lee, T. Y.; Charusiri, P.

2012-04-01

The Mae Ping Shear Zone (MPSZ, also known as Wang Chao Fault Zone), which trends NW-SE from Myanmar to central Thailand, was considered as the southern boundary of the SE extrusion of Indochina and Sibumasu block during the Cenozoic escape tectonic event of SE asia. Many analyses of 40Ar/39Ar dating on biotite and K-feldspar, K/Ar dating on biotite and illite, zircon fission-track and apatite fission-track dating had been accomplished to constrain the shearing period. Nevertheless, it is hard to convince that the ages could represent the end of the shearing since none of the dated minerals have been proved to be crystallized syn-tectonically. Meta-granitoid and gneiss from the MPSZ were analyzed in this study by applying in-situ 40Ar/39Ar laser probe dating with combination of petrology and micro-structural analysis in the purpose to decipher the geological significance of the dates. Plagioclase was replacing K-feldspar for K-feldspar was cut and embayed by plagioclase observed by SEM + EDS. Muscovite in the granitoid own fish shapes of sinistral sense of shearing, and are always in contact with plagioclase and quartz, which suggests that the muscovite crystallized from the dissolving K-feldspar under amphibolite facies condition. 117 spots on 12 muscovite fishes yield ages from 44 Ma to 35 Ma and have a mean age of 40 Ma. Since the growth condition of the muscovite is higher than the closure temperature, thus we can interpret these muscovite ages as cooling ages. Hence left-lateral shearing of the MPSZ can be deduced as syn- to post-muscovite growth and uplifted the crystalline rocks within the shear zone. The ages of matrix biotite in gneiss has a mean age of 35 Ma, which is consistent with the cooling path reconstructed from previous studies. While the ages of inclusion biotite in the K-feldspar phenocryst scatter from 40 to 50 Ma due to the isotopes were not totally re-equilibrated during the shearing. Consequently, the left-lateral shearing of the MPSZ was

Single grains, thermal histories, and the 40Ar/39Ar method

International Nuclear Information System (INIS)

Wright, Norrie

1989-01-01

A key part in unraveling the history of the physical evolution of the earth is knowledge of the earth's thermal history. 40 Ar/ 39 Ar step heating of mineral samples provides a means of defining a local thermal history. to do this accurately the challenge is to extract meaningful diffusion parameters from a mineral's Arrhenius plot. In the case of biotite single grains, where the laboratory release of argon is a complex process, this can be a difficult task. (12 refs., 5 figs.)

Ars Electronica tulekul / Rael Artel

Index Scriptorium Estoniae

Artel, Rael, 1980-

2003-01-01

6.-11. IX toimub Austrias Linzis "Ars Electronica" festival, mille teema on "Code - The Language of Our Time". Festivali kavast, osalejatest, ava-performance'ist "Europe - A Symphonic Vision", näitusest "Cyberarts 2003. Prix Ars Electronica"

^<40>Ar-^<39>Ar Age Studies for Tectonics of the Gondwana Land

OpenAIRE

Takigami, Yutaka; Sugiura, Naoji

1997-01-01

^Ar-^Ar age studies have been performed for samples from Antarctica and India which were parts of the Gondwana land at Mesozoic and Paleozoic time in order to investigate their thermal history and tectonic movement. From the both areas, ages of about 500 Ma which have been considered to be the age of Pan-African Orogeny were obtained, which represents that this thermal event spread widely over the Gondwana land.

GPS-Based AR Games Development Potential

Directory of Open Access Journals (Sweden)

Gregorius Alvin Raditya Santoso

2014-11-01

Full Text Available The application of new technologies in a game is not a new thing. One example is the application of Augmented Reality (AR technology in game. Many people do not know the application of AR technology in game, although the application of this technology is able to produce a game with unique gameplay. In addition, since AR game is GPS-based, it offers new gaming experience, that is, playing outdoors in which the real world becomes the game arena. This advantage gives the AR technology a huge potential to be developed into a game

Evolution of the Ar isotopic chain: the N=28 shell gap south of {sup 48}Ca

Energy Technology Data Exchange (ETDEWEB)

Mengoni, D., E-mail: Daniele.Mengoni@uws.ac.u [Dipartimento di Fisica dell' Universita and INFN Sezione di Padova, Padova (Italy); Valiente-Dobon, J.J. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Gadea, A. [Instituto de Fisica Corpuscular, CSIC-Universidad de Valencia (Spain); Lenzi, S.M.; Lunardi, S. [Dipartimento di Fisica dell' Universita and INFN Sezione di Padova, Padova (Italy); Broda, R. [Institute of Nuclear Physics, Polish Academy of Sciences, Cracow (Poland); Dewald, A.; Pissulla, T. [Institut fuer Kernphysik der Universtaet zu Koeln, Koeln (Germany); Angus, L. [School of Engineering and Science, University of Paisley, Paisley, Scotland (United Kingdom); Aydin, S.; Bazzacco, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Benzoni, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy); Bizzeti, P.G.; Bizzeti-Sona, A.M. [Dipartimento di Fisica dell' Universita and INFN Sezione di Firenze, Firenze (Italy); Corradi, L. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Crespi, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy); Angelis, G. de [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Farnea, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, Padova (Italy); Fioretto, E. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro (Italy); Goergen, A. [CEA Saclay, Daphnia/SphN, Gif-sur-Yvette Cedex (France)

2010-03-01

The lifetimes of the first excited states of the Z = 18 {sup 44}Ar and {sup 46}Ar isotopes have been determined using a novel technique that combines the Recoil Distance Doppler Shift method with the CLARA-PRISMA spectrometers for Multinucleon Transfer Reactions. The B(E2) values extracted for the 2{sup +}->0{sup +} transitions in both nuclei, as well as for higher excites states in {sup 44}Ar, are discussed and compared with the available experimental results and with the new large-scale shell-model calculations.

40Ar-39Ar age studies for tectonics of the Gondwana land

International Nuclear Information System (INIS)

Takigami, Yutaka; Sugiura, Naoji.

1997-01-01

40 Ar- 39 Ar age studies have been performed for samples from Antarctica and India which were parts of the Gondwana land at Mesozoic and Paleozoic time in order to investigate their thermal history and tectonic movement. From the both areas, ages of about 500 Ma which have been considered to be the age of Pan-African Orogeny were obtained, which represents that this thermal event spread widely over the Gondwana land. (author)

On the relationship between atmospheric rivers (ARs) and heavy precipitation over Japan

Science.gov (United States)

Yatagai, A. I.; Takayabu, Y. N.

2016-12-01

precipitation of exceeding 500 mm/2days, and 184 cases of exceeding 400 mm/2days. Excepting typhoon events, ARs appeared over Japan area. Detailed comparison (location, vertical profile, dynamical linkage, etc) will be reported at the meeting.

Apmierinātības ar dzīvi saistība ar laika perspektīvu

OpenAIRE

Selga, Toms

2013-01-01

Pētījuma mērķis ir noskaidrot vai pastāv saistības starp apmierinātību ar dzīvi un laika perspektīvu. Tika sagaidīts, ka indivīdiem, kam izteiktākas pozitīvās pagātnes un tagadnes hedoniskā laika uztvere, apmierinātības ar dzīvi rezultāti būs augstāki, bet indivīdiem ar negatīvās pagātnes uztveri apmierinātības ar dzīvi rādītāji būs zemāki (Zhang & Howell, 2011). Lai to noskaidrotu, tika izmantota apmierinātības ar dzīvi aptauja (Satisfaction With Life Scale, SWLS, Diener, Emmons, Larsen,...

A test of the 40Ar/39Ar age spectrum technique on some terrestrial materials

Science.gov (United States)

Lanphere, M.A.; Brent, Dalrymple G.

1971-01-01

40Ar/39Ar age spectra were determined for 10 terrestrial rock and mineral samples whose geologic history is known from independent evidence. The spectra for six mineral and whole rock samples, including biotite, feldspar, hornblende, muscovite, and granodiorite, that have experienced post-crystallization heating did not reveal the age of crystallization in any obvious way. Minima in the spectra, however, give reasonable maximum ages for reheating and high-temperature maxima can be interpreted as minimum crystallization ages. High-temperature ages of microcline and albite that have not been reheated are approximately 10% younger than the known crystallization age. Apparently there are no domains in these feldspars that have retained radiogenic 40Ar quantitatively. Spectra from two diabase samples that contain significant quantities of excess argon might mistakenly be interpreted as spectra from reheated samples and do not give the age of emplacement. The 40Ar/39Ar age spectrum technique may be a potentially valuable tool for the study of geologic areas with complex histories, but the interpretation of age spectra from terrestrial samples seems to be more difficult than suggested by some previous studies. ?? 1971.

Splicing Factor Prp8 Interacts With NES(AR) and Regulates Androgen Receptor in Prostate Cancer Cells.

Science.gov (United States)

Wang, Dan; Nguyen, Minh M; Masoodi, Khalid Z; Singh, Prabhpreet; Jing, Yifeng; O'Malley, Katherine; Dar, Javid A; Dhir, Rajiv; Wang, Zhou

2015-12-01

Androgen receptor (AR) plays a pivotal role in the development of primary as well as advanced castration-resistant prostate cancer. Previous work in our lab identified a novel nuclear export signal (NES) (NES(AR)) in AR ligand-binding domain essential for AR nucleocytoplasmic trafficking. By characterizing the localization of green fluorescence protein (GFP)-tagged NES(AR), we designed and executed a yeast mutagenesis screen and isolated 7 yeast mutants that failed to display the NES(AR) export function. One of those mutants was identified as the splicing factor pre-mRNA processing factor 8 (Prp8). We further showed that Prp8 could regulate NES(AR) function using short hairpin RNA knockdown of Prp8 coupled with a rapamycin export assay in mammalian cells and knockdown of Prp8 could induce nuclear accumulation of GFP-tagged AR in PC3 cells. Prp8 expression was decreased in castration-resistant LuCaP35 xenograft tumors as compared with androgen-sensitive xenografts. Laser capture microdissection and quantitative PCR showed Prp8 mRNA levels were decreased in human prostate cancer specimens with high Gleason scores. In prostate cancer cells, coimmunoprecipitation and deletion mutagenesis revealed a physical interaction between Prp8 and AR mainly mediated by NES(AR). Luciferase assay with prostate specific antigen promoter-driven reporter demonstrated that Prp8 regulated AR transcription activity in prostate cancer cells. Interestingly, Prp8 knockdown also increased polyubiquitination of endogenous AR. This may be 1 possible mechanism by which it modulates AR activity. These results show that Prp8 is a novel AR cofactor that interacts with NES(AR) and regulates AR function in prostate cancer cells.

244-AR Vault Interim Stabilization Project Plan

International Nuclear Information System (INIS)

LANEY, T.

2000-01-01

The 244-AR Vault Facility, constructed between 1966 and 1968, was designed to provide lag storage and treatment for the Plutonium-Uranium Extraction Facility (PUREX) tank farm sludges. Tank farm personnel transferred the waste from the 244-AR Vault Facility to B Plant for recovery of cesium and strontium. B Plant personnel then transferred the treatment residuals back to the tank farms for storage of the sludge and liquids. The last process operations, which transferred waste supporting the cesium/strontium recovery mission, occurred in April 1978. After the final transfer in 1978, the 244-AR facility underwent a cleanout. However, 2,271 L (600 gal) of sludge were left in Tank 004AR from an earlier transfer from Tank 241-AX-104. When the cleanout was completed, the facility was placed in a standby status. The sludge had been transferred to Tank 004AR to support Pacific Northwest National Laboratory [PNNL] vitrification work. Documentation of waste transfers suggests that a portion of the sludge may have been moved from Tank 004AR to Tank 002AR in preparation for transfer back to the AX Tank Farm; however, quantities of the sludge that were moved to Tank 002AR from that transfer must be estimated

Dating method with /sup 39/Ar

Energy Technology Data Exchange (ETDEWEB)

Loosli, H H [Bern Univ. (Switzerland). Physikalisches Inst.

1983-04-01

The principles of a dating method based on the cosmic-ray-produced radioisotope /sup 39/Ar are given. Technical requirements such as background and standard gas samples and gas proportional counting systems are described. With samples extracted from Greenland ice it can be demonstrated that /sup 39/Ar ages agree with ages obtained by other methods. First results on ocean water samples show that with this isotope valuable information on ocean mixing and circulation can be expected. /sup 39/Ar results on groundwater samples disagree for some aquifers with conventional /sup 14/C ages; possible explanations are discussed, especially underground production of /sup 39/Ar.

40Ar-39Ar dating of terrestrial and exterrestrial materials. Basalts from the Japan Sea floor, Deccan Plateau and meteorites from Antarctica

International Nuclear Information System (INIS)

Kaneoka, Ichiro; Takigami, Yutaka.

1994-01-01

Through a series of 40 Ar- 39 Ar dating for terrestrial and exterrestrial samples, the results for basalts from the Japan Sea floor, Deccan Plateau and for meteorites from Antarctica give significant information concerning their formation histories. 40 Ar- 39 Ar ages of basalts from the Japan Sea floor give a constraint that the Japan Sea floor was formed at least 20 Ma. 40 Ar- 39 Ar ages for dyke samples from the Deccan Plateau indicate a possibility for the occurrence of a little younger ages than that of the main plateau formations by a few million years. Meteorites collected from Antarctica show some variable 40 Ar- 39 Ar ages reflecting their different thermal histories. (author)

Energy dependence of the reaction rate constants of Ar+, Ar++ and N2+ ions with Cl2

International Nuclear Information System (INIS)

Lukac, P.; Holubcik, L.; Morva, I.; Lindinger, W.

2002-01-01

Dry etching processes using low temperature plasmas in Cl 2 and in Cl 2 -noble gas or nitrogen mixtures are common in the manufacture of semiconductor devices, but their chemical mechanisms are often poorly understood. Results are given for the reaction rate constant measurements of Ar + , Ar ++ , N 2 + ions with chlorine as a function of mean relative kinetic energy. The experiments were performed by using the innsbruck flow drift tube (IFDT) apparatus. Measurements were done at various E/N values, where E is the electric field strength and N the buffer gas density in the drift section. The mean relative kinetic energy KE CM between the ions and the neutral chlorine Cl 2 was calculated using the Wanniers formula. It was found that The N 2 + , Ar + and Ar ++ positive ions react with chlorine Cl 2 very fast and the corresponding reaction rate coefficients depend on the mean relative kinetic energy. For the reaction of Ar - with Cl 2 , its reaction coefficient depends also on the buffer gas. It can imply the enhancement of Cl 2 + ions during etching of Si in the Ar/Cl 2 mixtures. (nevyjel)

Support for the Astronomically Calibrated 40Ar/39Ar Age of Fish Canyon Sanidine

DEFF Research Database (Denmark)

Rivera, Tiffany; Storey, Michael; Zeeden, Christian

2011-01-01

al. (2008) determined an astronomically calibrated 40Ar/39Ar age of 28.201 0.046 Ma (2), relative to the indirect astronomically tuned Moroccan Melilla Basin Messâdit section. Here, we provide independent verification for the Kuiper, et al. (2008) FCs age using sanidines extracted from the A1 tephra...

Microarea dating of mineral and rock. The application of technique by combining 40Ar/39Ar mass spectrometer with laser probe

International Nuclear Information System (INIS)

Hu Shiling; Dai Tongmo; Pu Zhiping

1998-01-01

The 40 Ar/ 39 Ar dating of probe technique by the continuous laser is successfully applied to determine the ages of microarea samples for mineral and whole rock, including the standard samples from internal and abroad, volcanical rock from westsouthern Antarctica and Green Pissolites of Guizhou. Isochron ages for volcanical rock to be excess or lost argon are accomplished by the whole fused, and for 'green Pisolites' not only by the whole fused, but also by the steps heat. All of which shows the significant geological ages. It would be exhibited the obvious advantage for dating some special samples to make the microarea 40 Ar/ 39 Ar dating technique by laser probe as compare with conventional K-Ar and 40 Ar/ 39 Ar methods

40Ar/39Ar age of the Rotoiti Breccia and Rotoehu Ash, Okataina Volcanic Complex, New Zealand, and identification of heterogeneously distributed excess 40Ar in supercooled crystals

DEFF Research Database (Denmark)

Flude, Stephanie; Storey, Michael

2016-01-01

Co-magmatic granitoid clasts erupted as part of the Rotoiti Ignimbrite (Rotoehu Tephra) contain euhedral K-feldspar and biotite crystals that protrude into miarolytic cavities and show textural evidence for growth in super-cooled conditions and are thus interpreted as growing during eruption. 40Ar...... that appear to be largely unaffected by excess 40Ar. This population gives a statistically robust weighted mean age of 47.4 ± 1.5 ka (1σ, n = 13) and an indistinguishable inverse isochron age of 50 ± 3 ka for this historically difficult to date eruption. The weighted mean age is significantly younger than...... previous age estimates of the Rotoiti eruption obtained by K/Ar and 40Ar/39Ar dating of bracketing lavas, but is indistinguishable from recent 14C and (U–Th)/He dates and estimates based on orbital tuning and sedimentation rates constrained by 14C ages....

Timing of Hydrocarbon Fluid Emplacement in Sandstone Reservoirs in Neogene in Huizhou Sag, Southern China Sea, by Authigenic Illite 40Ar- 39Ar Laser Stepwise Heating

Science.gov (United States)

Hesheng, Shi; Junzhang, Zhu; Huaning, Qiu; yu, Shu; Jianyao, Wu; Zulie, Long

Timing of oil or gas emplacements is a new subject in isotopic geochronology and petroleum geology. Hamilton et al. expounded the principle of the illite K-Ar age: Illite is often the last or one of the latest mineral cements to form prior to hydrocarbon accumulation. Since the displacement of formation water by hydrocarbons will cause silicate diagenesis to cease, K-Ar ages for illite will constrain the timing of this event, and also constrain the maximum age of formation of the trap structure. In this study, the possibility of authigenic illites 40Ar- 39Ar dating has been investigated. The illite samples were separated from the Tertiary sandstones in three rich oil reservoir belts within the Huizhou sag by cleaning, fracturing by cycled cooling-heating, soxhlet-extraction with solvents of benzene and methanol and separating with centrifugal machine. If oil is present in the separated samples, ionized organic fragments with m/e ratios of 36 to 40 covering the argon isotopes will be yielded by the ion source of a mass spectrometer, resulting in wrong argon isotopic analyses and wrong 40Ar- 39Ar ages. The preliminary experiments of illite by heating did show the presence of ionized organic fragments with m/e ratios of 36 to 44. In order to clean up the organic gases completely and obtain reliable analysis results, a special purification apparatus has been established by Qiu et al. and proved valid by the sequent illite analyses. All the illite samples by 40Ar- 39Ar IR-laser stepwise heating yield stair-up age spectra in lower laser steps and plateaux in higher laser steps. The youngest apparent ages corresponding to the beginning steps are reasonable to be interpreted for the hydrocarbon accumulation ages. The weighted mean ages of the illites from the Zhuhai and Zhujiang Formations are (12.1 ± 1.1) Ma and (9.9 ± 1.2) Ma, respectively. Therefore, the critical emplacement of petroleum accumulation in Zhujiang Formation in Huizhou sag took place in ca 10 Ma. Late

Selective AR Modulators that Distinguish Proliferative from Differentiative Gene Promoters

Science.gov (United States)

2017-08-01

Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the author(s) and should not be...Research and Materiel Command Fort Detrick, Maryland 21702-5012 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT...recognition, we performed a high -throughput screen for compounds eliciting differential AR activity on cARE vs. sARE reporters. Of 10,000 compounds

Acupuncture Prevents the Impairment of Hippocampal LTP Through β1-AR in Vascular Dementia Rats.

Science.gov (United States)

Xiao, Ling-Yong; Wang, Xue-Rui; Yang, Jing-Wen; Ye, Yang; Zhu, Wen; Cao, Yan; Ma, Si-Ming; Liu, Cun-Zhi

2018-02-13

It is widely accepted that the synaptic dysfunction and synapse loss contribute to the cognitive deficits of vascular dementia (VD) patients. We have previously reported that acupuncture improved cognitive function in rats with VD. However, the mechanisms involved in acupuncture improving cognitive ability remain to be elucidated. The present study aims to investigate the pathways and molecules involved in the neuroprotective effect of acupuncture. We assessed the effects of acupuncture on hippocampal long-term potentiation (LTP), the most prominent cellular model of memory formation. Acupuncture enhanced LTP and norepinephrine (NE) levels in the hippocampus. Inhibition of the β-adrenergic receptor (AR), but not the α-AR, was able to block the effects of acupuncture on hippocampal LTP. Furthermore, inhibition of β1-AR, not β2-AR, abolished the enhanced LTP induced by acupuncture. The expression analysis revealed a significant upregulation of β1-AR and unchanged β2-AR with acupuncture, which supported the above findings. Specifically, increased β1-ARs in the dentate gyrus were expressed on neurons exclusively. Taken together, the present data supports a beneficial role of acupuncture in synaptic plasticity challenged with VD. A likely mechanism is the increase of NE and activation of β1-AR in the hippocampus.

The ArDM experiment

CERN Document Server

Haranczyk, M; Badertscher, A; Boccone, V; Bourgeois, N; Bueno, A; Carmona-Benitez, M C; Chorowski, M; Creus, W; Curioni, A; Daw, E; Degunda, U; Dell'Antone, A; Droge, M; Epprecht, L; Haller, C; Horikawa, S; Kaufmann, L; Kisiel, J; Knecht, L; Laffranchi, M; Lagoda, J; Lazzaro, C; Lightfoot, P; Lozano, J; Lussi, D; Maire, G; Mania, S; Marchionni, A; Mavrokoridis, K; Melgarejo, A; Mijakowski, P; Natterer, G; Navas-Concha, S; Otiougova, P; Piotrowska, A; Polinski, J; de Prado, M; Przewlocki, P; Ravat, S; Regenfus, C; Resnati, F; Robinson, M; Rochet, J; Romero, L; Rondio, E; Rubbia, A; Scotto-Lavina, L; Spooner, N; Viant, T; Trawinski, A; Ulbricht, J; Zalewska, A

2010-01-01

The aim of the ArDM project is the development and operation of a one ton double-phase liquid argon detector for direct Dark Matter searches. The detector measures both the scintillation light and the ionization charge from ionizing radiation using two independent readout systems. This paper briefly describes the detector concept and presents preliminary results from the ArDM R&D program, including a 3 l prototype developed to test the charge readout system.

Medium-Index Mixed-Oxide Layers for Use in AR-Coatings

Science.gov (United States)

Ganner, Peter

1986-10-01

Ttedesign philosophy of MC-AR-Coatings can be divided into two categories: a) Restriction to two film materials, namely one high-index and one low-index material and b) Use of medium-index layers in addition to high- and low-index layers. Both philosophies have advan-tages and drawbacks. In case a) the total number of layers necessary to obtain a required reflectance curve has to be higher. Thus in case of production errors it can be a problem to find out which layer was responsible for a deviation of the measured reflectance from the nominal one. In case b) using more than two materials reduces the total number of layers and consequently, pinpointing the cause of even small production errors is made simpler. Unfortunately there are not many materials commercially available which can be used to make hard, durable and robust films in the medium-index range namely between n=1.65 and n=2.00. In this paper the results of homogeneous mixtures of Alumina (Al203) and Tantala (Ta205) used for EB-gun evaporated medium-index films in AR-coatings is presented. It is shown that by proper adjustment of the weight percentages of the oxide mixture one can get homogeneous films in this index range. A number of design examples show the favourable application of such layers in AR-coatings. Among the most important ones is the well known QHQ-design for BBAR-coatings as well as AR-designs of the multiple half wave type with extended bandwidth. Further applications of the mixed-oxide layers are AR-coatings for cemented optical elements and beam splitters.

Light Curve Variations of AR Lacertae

Directory of Open Access Journals (Sweden)

Il-Seong Nha

1991-12-01

Full Text Available Sixteen unitary Light curves of AR Lac in B and V are made at Yonsei University Observatory in the period of 1980-1988. Some overview findings of light variations are made. (1 The light variations outside eclipse follow none of the wave migration patterns reported by previous investigators. (2 Complicated shapes outside eclipse are apparently much reduced in the light curves of 1983-1984. This suggests that, in the future, AR Lac has a chance to attain a normal state with mo complicated interactions. (3 The depths of the primary and the secondary mid-eclipses are changing year-to-year. (4 The K0 star, the larger component, has brightened by 0.m14 V, while the G2 star has shown a fluctuation of about 0.m05 in V. (5 The B-V values at primary mid-eclipse have no correlation with the depth variations. (6 Independently of the increase of maximum brightness, the B-V colors in the non-eclipsed phases changed slightly over the years.

The potential of AR-V7 as a therapeutic target.

Science.gov (United States)

Uo, Takuma; Plymate, Stephen R; Sprenger, Cynthia C

2018-03-01

The androgen receptor variant AR-V7 is gaining attention as a potential predictive marker for as well as one of the resistance mechanisms to the most current anti-androgen receptor (AR) therapies in castration-resistant prostate cancer (CRPC). Accordingly, development of next-generation drugs that directly or indirectly target AR-V7 signaling is urgently needed. Areas covered: We review proposed mechanisms of drug resistance in relation to AR-V7 status, the mechanisms of generation of AR-V7, and its transcriptome, cistrome, and interactome. Pharmacological agents that interfere with these processes are being developed to counteract pan AR and AR-V7-specific signaling. Also, we address the current status of the preclinical and clinical studies targeting AR-V7 signaling. Expert opinion: AR-V7 is considered a true therapeutic target, however, it remains to be determined if AR-V7 is a principal driver or merely a bystander requiring heterodimerization with co-expressed full-length AR or other variants to drive CRPC progression. While untangling AR-V7 biology, multiple strategies are being developed to counteract drug resistance, including selective blockade of AR-V7 signaling as well as inhibition of pan-AR signaling. Ideally anti-AR therapies will be combined with agents preventing activation and enrichment of AR negative tumor cells that are otherwise depressed by AR activity axis.

Argon defect complexes in low energy Ar irradiated molybdenum

International Nuclear Information System (INIS)

Veen, A. van; Buters, W.T.M.; Kolk, G.J. van der; Caspers, L.M.; Armstrong, T.R.

1982-01-01

Thermal desorption spectrometry has been used to study the defects created in Mo irradiated along the direction with Ar ions ranging in energy from 0.1 to 2 keV. In addition to monitoring the release of the implanted Ar, additional information has been obtained by decoration of the defects with low energy helium and subsequent monitoring of the helium release. The studies show evidence that the Ar can be trapped in both substitutional sites and in a configuration in which the Ar is associated with vacancies (ArVsub(n), n >= 2). Most of the Ar implanted at high energy is released at approx. equal to 1500 K by thermal vacancy assisted diffusion. Argon trapped closer to the surface is released at lower temperatures via at least three different surface related release mechanisms. Additional results are presented on the interaction of self interstitial atoms (introduced by 100 eV Xe bombardment) with the Ar defects. Substitutional Ar is found to convert to interstitial Ar which seems to be mobile at room temperature. The Ar-vacancy complexes are found to be reduced to substitutional Ar. The results of atomistic calculations of the release mechanisms will also be presented. (orig.)

Degradation Assessment and Fault Diagnosis for Roller Bearing Based on AR Model and Fuzzy Cluster Analysis

Directory of Open Access Journals (Sweden)

Lingli Jiang

2011-01-01

Full Text Available This paper proposes a new approach combining autoregressive (AR model and fuzzy cluster analysis for bearing fault diagnosis and degradation assessment. AR model is an effective approach to extract the fault feature, and is generally applied to stationary signals. However, the fault vibration signals of a roller bearing are non-stationary and non-Gaussian. Aiming at this problem, the set of parameters of the AR model is estimated based on higher-order cumulants. Consequently, the AR parameters are taken as the feature vectors, and fuzzy cluster analysis is applied to perform classification and pattern recognition. Experiments analysis results show that the proposed method can be used to identify various types and severities of fault bearings. This study is significant for non-stationary and non-Gaussian signal analysis, fault diagnosis and degradation assessment.

Use of an A.E.I. MS 10 mass spectrometer for 40Ar-39Ar dating

International Nuclear Information System (INIS)

Baksi, A.K.

1979-01-01

The use of an AEI mass spectrometer for 40 Ar/ 39 Ar dating could, in principle, be problematical due to its limited mass resolution and because of non-linear mass discrimination under certain operating conditions. These possible drawbacks have been investigated and are found to be easy to overcome. Tailing corrections are relatively small and can be applied precisely for 40 Ar/ 39 Ar ratios <= 300. By operating the instrument with a trap current of 50 μA and an ion repeller voltage of +1.0 w.r.t. cage, problems due to non-linear mass discrimination are eliminated. Using the incremental heating technique and total fusion studies on very small subsamples (10-25 mg.), the homogeneity of some well-known inter-laboratory standards has been investigated; the relative merits of these standards are discussed. (K.B.)

Modelling the ArH+ emission from the Crab nebula

Science.gov (United States)

Priestley, F. D.; Barlow, M. J.; Viti, S.

2017-12-01

We have performed combined photoionization and photodissociation region (PDR) modelling of a Crab nebula filament subjected to the synchrotron radiation from the central pulsar wind nebula, and to a high flux of charged particles; a greatly enhanced cosmic-ray ionization rate over the standard interstellar value, ζ0, is required to account for the lack of detected [C I] emission in published Herschel SPIRE FTS observations of the Crab nebula. The observed line surface brightness ratios of the OH+ and ArH+ transitions seen in the SPIRE FTS frequency range can only be explained with both a high cosmic-ray ionization rate and a reduced ArH+ dissociative recombination rate compared to that used by previous authors, although consistent with experimental upper limits. We find that the ArH+/OH+ line strengths and the observed H2 vibration-rotation emission can be reproduced by model filaments with nH = 2 × 104 cm-3, ζ = 107ζ0 and visual extinctions within the range found for dusty globules in the Crab nebula, although far-infrared emission from [O I] and [C II] is higher than the observational constraints. Models with nH = 1900 cm-3 underpredict the H2 surface brightness, but agree with the ArH+ and OH+ surface brightnesses and predict [O I] and [C II] line ratios consistent with observations. These models predict HeH+ rotational emission above detection thresholds, but consideration of the formation time-scale suggests that the abundance of this molecule in the Crab nebula should be lower than the equilibrium values obtained in our analysis.

FOXA1 promotes tumor cell proliferation through AR involving the Notch pathway in endometrial cancer

International Nuclear Information System (INIS)

Qiu, Meiting; Bao, Wei; Wang, Jingyun; Yang, Tingting; He, Xiaoying; Liao, Yun; Wan, Xiaoping

2014-01-01

Increasing evidence suggests that forkhead box A1 (FOXA1) is frequently dysregulated in many types of human cancers. However, the exact function and mechanism of FOXA1 in human endometrial cancer (EC) remains unclear. FOXA1 expression, androgen receptor (AR) expression, and the relationships of these two markers with clinicopathological factors were determined by immunohistochemistry analysis. FOXA1 and AR were up-regulated by transient transfection with plasmids, and were down-regulated by transfection with siRNA or short hairpin RNA (shRNA). The effects of FOXA1 depletion and FOXA1 overexpression on AR-mediated transcription as well as Notch pathway and their impact on EC cell proliferation were examined by qRT-PCR, western blotting, co-immunoprecipitation, ChIP-PCR, MTT, colony-formation, and xenograft tumor–formation assays. We found that the expression of FOXA1 and AR in ECs was significantly higher than that in a typical hyperplasia and normal tissues. FOXA1 expression was significantly correlated with AR expression in clinical tissues. High FOXA1 levels positively correlated with pathological grade and depth of myometrial invasion in EC. High AR levels also positively correlated with pathological grade in EC. Moreover, the expression of XBP1, MYC, ZBTB16, and UHRF1, which are downstream targets of AR, was promoted by FOXA1 up-regulation or inhibited by FOXA1 down-regulation. Co-immunoprecipitation showed that FOXA1 interacted with AR in EC cells. ChIP-PCR assays showed that FOXA1 and AR could directly bind to the promoter and enhancer regions upstream of MYC. Mechanistic investigation revealed that over-expression of Notch1 and Hes1 proteins by FOXA1 could be reversed by AR depletion. In addition, we showed that down-regulation of AR attenuated FOXA1-up-regulated cell proliferation. However, AR didn’t influence the promotion effect of FOXA1 on cell migration and invasion. In vivo xenograft model, FOXA1 knockdown reduced the rate of tumor growth. These

StAR Enhances Transcription of Genes Encoding the Mitochondrial Proteases Involved in Its Own Degradation

Science.gov (United States)

Bahat, Assaf; Perlberg, Shira; Melamed-Book, Naomi; Lauria, Ines; Langer, Thomas

2014-01-01

Steroidogenic acute regulatory protein (StAR) is essential for steroid hormone synthesis in the adrenal cortex and the gonads. StAR activity facilitates the supply of cholesterol substrate into the inner mitochondrial membranes where conversion of the sterol to a steroid is catalyzed. Mitochondrial import terminates the cholesterol mobilization activity of StAR and leads to mounting accumulation of StAR in the mitochondrial matrix. Our studies suggest that to prevent mitochondrial impairment, StAR proteolysis is executed by at least 2 mitochondrial proteases, ie, the matrix LON protease and the inner membrane complexes of the metalloproteases AFG3L2 and AFG3L2:SPG7/paraplegin. Gonadotropin administration to prepubertal rats stimulated ovarian follicular development associated with increased expression of the mitochondrial protein quality control system. In addition, enrichment of LON and AFG3L2 is evident in StAR-expressing ovarian cells examined by confocal microscopy. Furthermore, reporter studies of the protease promoters examined in the heterologous cell model suggest that StAR expression stimulates up to a 3.5-fold increase in the protease gene transcription. Such effects are StAR-specific, are independent of StAR activity, and failed to occur upon expression of StAR mutants that do not enter the matrix. Taken together, the results of this study suggest the presence of a novel regulatory loop, whereby acute accumulation of an apparent nuisance protein in the matrix provokes a mitochondria to nucleus signaling that, in turn, activates selected transcription of genes encoding the enrichment of mitochondrial proteases relevant for enhanced clearance of StAR. PMID:24422629

DBC1 promotes castration-resistant prostate cancer by positively regulating DNA binding and stability of AR-V7.

Science.gov (United States)

Moon, Sue Jin; Jeong, Byong Chang; Kim, Hwa Jin; Lim, Joung Eun; Kwon, Ghee Young; Kim, Jeong Hoon

2018-03-01

Constitutively active AR-V7, one of the major androgen receptor (AR) splice variants lacking the ligand-binding domain, plays a key role in the development of castration-resistant prostate cancer (CRPC) and anti-androgen resistance. However, our understanding of the regulatory mechanisms of AR-V7-driven transcription is limited. Here we report DBC1 as a key regulator of AR-V7 transcriptional activity and stability in CRPC cells. DBC1 functions as a coactivator for AR-V7 and is required for the expression of AR-V7 target genes including CDH2, a mesenchymal marker linked to CRPC progression. DBC1 is required for recruitment of AR-V7 to its target enhancers and for long-range chromatin looping between the CDH2 enhancer and promoter. Mechanistically, DBC1 enhances DNA-binding activity of AR-V7 by direct interaction and inhibits CHIP E3 ligase-mediated ubiquitination and degradation of AR-V7 by competing with CHIP for AR-V7 binding, thereby stabilizing and activating AR-V7. Importantly, DBC1 depletion suppresses the tumorigenic and metastatic properties of CRPC cells. Our results firmly establish DBC1 as a critical AR-V7 coactivator that plays a key role in the regulation of DNA binding and stability of AR-V7 and has an important physiological role in CRPC progression.

MEIS1 functions as a potential AR negative regulator

Energy Technology Data Exchange (ETDEWEB)

Cui, Liang [Department of Urology, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China); Department of Urology, Civil Aviation General Hospital/Civil Aviation Medical College of Peking University, Beijing 100123 (China); Li, Mingyang [Department of Gastroenterology, Nan Lou Division, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China); Feng, Fan [Department of Pharmacy, General Hospital of Shenyang Military Command, Shenyang 110016 (China); Yang, Yutao [Beijing Institute for Neuroscience, Capital Medical University, Beijing 100069 (China); Hang, Xingyi [National Scientific Data Sharing Platform for Population and Health, Beijing 100730 (China); Cui, Jiajun, E-mail: cuijn@ucmail.uc.edu [Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, Cincinnati, OH 45267 (United States); Gao, Jiangping, E-mail: jpgao@163.com [Department of Urology, Chinese PLA Medical School/Chinese PLA General Hospital, Beijing 100853 (China)

2014-10-15

The androgen receptor (AR) plays critical roles in human prostate carcinoma progression and transformation. However, the activation of AR is regulated by co-regulators. MEIS1 protein, the homeodomain transcription factor, exhibited a decreased level in poor-prognosis prostate tumors. In this study, we investigated a potential interaction between MEIS1 and AR. We found that overexpression of MEIS1 inhibited the AR transcriptional activity and reduced the expression of AR target gene. A potential protein–protein interaction between AR and MEIS1 was identified by the immunoprecipitation and GST pull-down assays. Furthermore, MEIS1 modulated AR cytoplasm/nucleus translocation and the recruitment to androgen response element in prostate specific antigen (PSA) gene promoter sequences. In addition, MEIS1 promoted the recruitment of NCoR and SMRT in the presence of R1881. Finally, MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells. Taken together, our data suggests that MEIS1 functions as a novel AR co-repressor. - Highlights: • A potential interaction was identified between MEIS1 and AR signaling. • Overexpression of MEIS1 reduced the expression of AR target gene. • MEIS1 modulated AR cytoplasm/nucleus translocation. • MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells.

MEIS1 functions as a potential AR negative regulator

International Nuclear Information System (INIS)

Cui, Liang; Li, Mingyang; Feng, Fan; Yang, Yutao; Hang, Xingyi; Cui, Jiajun; Gao, Jiangping

2014-01-01

The androgen receptor (AR) plays critical roles in human prostate carcinoma progression and transformation. However, the activation of AR is regulated by co-regulators. MEIS1 protein, the homeodomain transcription factor, exhibited a decreased level in poor-prognosis prostate tumors. In this study, we investigated a potential interaction between MEIS1 and AR. We found that overexpression of MEIS1 inhibited the AR transcriptional activity and reduced the expression of AR target gene. A potential protein–protein interaction between AR and MEIS1 was identified by the immunoprecipitation and GST pull-down assays. Furthermore, MEIS1 modulated AR cytoplasm/nucleus translocation and the recruitment to androgen response element in prostate specific antigen (PSA) gene promoter sequences. In addition, MEIS1 promoted the recruitment of NCoR and SMRT in the presence of R1881. Finally, MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells. Taken together, our data suggests that MEIS1 functions as a novel AR co-repressor. - Highlights: • A potential interaction was identified between MEIS1 and AR signaling. • Overexpression of MEIS1 reduced the expression of AR target gene. • MEIS1 modulated AR cytoplasm/nucleus translocation. • MEIS1 inhibited the proliferation and anchor-independent growth of LNCaP cells

Microbiologia do ar : monitorização do ar em ambiente hospitalar

OpenAIRE

Santos, Ana Carina Marques dos

2008-01-01

O complexo ambiente hospitalar requer atenção especial, para assegurar uma saudável qualidade do ar interior, protegendo assim os profissionais de saúde e utentes de infecções nosocomiais e de doenças ocupacionais. Embora seja amplamente reconhecido que a contaminação de um bloco operatório seja a principal responsável pela complicação de uma cirurgia, em Portugal, estudos sobre microbiologia do ar a nível hospitalar são escassos. O objectivo deste estudo é investigar a vari...

Progress on using deuteron-deuteron fusion generated neutrons for 40Ar/39Ar sample irradiation

Science.gov (United States)

Rutte, Daniel; Renne, Paul R.; Becker, Tim; Waltz, Cory; Ayllon Unzueta, Mauricio; Zimmerman, Susan; Hidy, Alan; Finkel, Robert; Bauer, Joseph D.; Bernstein, Lee; van Bibber, Karl

2017-04-01

We present progress on the development and proof of concept of a deuteron-deuteron fusion based neutron generator for 40Ar/39Ar sample irradiation. Irradiation with deuteron-deuteron fusion neutrons is anticipated to reduce Ar recoil and Ar production from interfering reactions. This will allow dating of smaller grains and increase accuracy and precision of the method. The instrument currently achieves neutron fluxes of ˜9×107 cm-2s-1 as determined by irradiation of indium foils and use of the activation reaction 115In(n,n')115mIn. Multiple foils and simulations were used to determine flux gradients in the sample chamber. A first experiment quantifying the loss of 39Ar is underway and will likely be available at the time of the presentation of this abstract. In ancillary experiments via irradiation of K salts and subsequent mass spectrometric analysis we determined the cross-sections of the 39K(n,p)39Ar reaction at ˜2.8 MeV to be 160 ± 35 mb (1σ). This result is in good agreement with bracketing cross-section data of ˜96 mb at ˜2.45 MeV and ˜270 mb at ˜4 MeV [Johnson et al., 1967; Dixon and Aitken, 1961 and Bass et al. 1964]. Our data disfavor a much lower value of ˜45 mb at 2.59 MeV [Lindström & Neuer, 1958]. In another ancillary experiment the cross section for 39K(n,α)36Cl at ˜2.8 MeV was determined as 11.7 ± 0.5 mb (1σ), which is significant for 40Ar/39Ar geochronology due to subsequent decay to 36Ar as well as for the determination of production rates of cosmogenic 36Cl. Additional experiments resolving the cross section functions on 39K between 1.5 and 3.6 MeV are on their way using the LICORNE neutron source of the IPN Orsay tandem accelerator. Results will likely be available at the time of the presentation of this abstract. While the neutron generator is designed for fluxes of ˜109 cm-2s-1, arcing in the sample chamber currently limits the power—straightforwardly correlated to the neutron flux—the generator can safely be run at. Further

Rotationally inelastic scattering of methyl radicals with Ar and N{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Tkáč, Ondřej; Orr-Ewing, Andrew J., E-mail: a.orr-ewing@bristol.ac.uk [School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS (United Kingdom); Ma, Qianli; Dagdigian, Paul J., E-mail: pjdagdigian@jhu.edu [Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685 (United States); Stei, Martin [Institut für Ionenphysik und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck (Austria)

2015-01-07

The rotationally inelastic scattering of methyl radical with Ar and N{sub 2} is examined at collision energies of 330 ± 25 cm{sup −1} and 425 ± 50 cm{sup −1}, respectively. Differential cross sections (DCSs) were measured for different final n′ rotational levels (up to n′ = 5) of the methyl radicals, averaged over k′ sub-levels, using a crossed molecular beam machine with velocity map imaging. For Ar as a collision partner, we present a newly constructed ab initio potential energy surface and quantum mechanical scattering calculations of state-resolved DCSs. These computed DCSs agree well with the measurements. The DCSs for both Ar and N{sub 2} collision partners are strongly forward peaked for all spectroscopic lines measured. For scattering angles below 60°, the theoretical CD{sub 3}–Ar DCSs show diffraction oscillations that become less pronounced as n′ increases, but these oscillations are not resolved experimentally. Comparisons are drawn with our recently reported DCSs for scattering of methyl radicals with He atoms.

Tibetan tectonics from 40Ar/39Ar analysis of a single K-feldspar sample

International Nuclear Information System (INIS)

Richter, F.M.; Lovera, O.M.; Harrison, T.M.; Copeland, P.

1991-01-01

40 Ar/ 39 Ar data on an alkali feldspar sample from the Quxu pluton, Gangdese batholith, southern Tibet, allow a detailed assessment of unroofing and uplift history between 35 and 18 Ma. The 39 Ar Arrhenius plot for this sample shows departures from a linear relationship between the effective diffusion parameter, log(D/r 2 ), and reciprocal temperature, which we interpret to be the result of a distribution of distinct diffusion-domain sizes. We use an alternative way of plotting the Arrhenius data that exhibits domain size versus cumulative % 39 Ar released during step heating. The 40 Ar/ 39 Ar age spectrum of the sample has features, such as local age plateaus, that are most easily explained in terms of the distinctive closure age of particular domains. The fact that the same distribution of diffusion-domain sizes explains both the Arrhenius data and the age spectrum is an indication that the diffusion properties operating in the laboratory are those of the sample while it was in its natural environment. Modelling of the age spectrum with a distribution of domain sizes results in the recovery of a continuous cooling-history segment rather than a single time-temperature datum. We demonstrate the robustness of the cooling-curve determination by showing the large misfits to the age spectrum that arise from relatively small changes in the cooling history. The best-fit cooling curve for the Quxu sample shows a decreasing rate of cooling in the time interval 35-18 Ma, followed by a very rapid cooling beginning at about 18 Ma. We have used a thermal model for the conductive cooling of an unroofing pluton to estimate the rate of unroofing required to explain the Quxu cooling curve, and find that in the 35-20 Ma time interval, the primary control of the thermal evolution is the conductive loss of magmatic heat with little or no unroofing (unroofing rates of approximately 0.05 mm/yr) followed by a brief period (<5 Ma) of very rapid unroofing with rates of order 2 mm

Comparative study of the Ar and He atmospheric pressure plasmas on E-cadherin protein regulation for plasma-mediated transdermal drug delivery

Science.gov (United States)

Lee, Hyun Young; Hae Choi, Jeong; Hong, Jin Woo; Kim, Gyoo Cheon; Lee, Hae June

2018-05-01

The effects of argon plasma (ArP) and helium plasma (HeP) jets on E-cadherin protein function have been tested in order to choose the working gas for a better plasma-mediated transdermal drug delivery. The plasma-mediated changes of the E-cadherin function and the skin penetration efficacies of epidermal growth factor (EGF) were monitored in vitro using HaCaT human keratinocytes and in vivo using hairless mice. The ArP showed higher efficacy for E-cadherin regulation and EGF absorption than HeP under the same applied voltage and the same gas flow rate. The ArP generates higher volume power density, higher discharge current peak, and more reactive species than HeP, especially for OH with the same operating parameters. Moreover, the effect of ArP on E-cadherin function was blocked by the use of a grounded metal mesh. Taken together, this study presents the possibility that the synergetic effect of negative charges with radicals plays an important role in plasma-mediated E-cadherin regulation, which leads to enhanced transdermal drug delivery.

Identification of an IL-1-induced gene expression pattern in AR+ PCa cells that mimics the molecular phenotype of AR- PCa cells.

Science.gov (United States)

Thomas-Jardin, Shayna E; Kanchwala, Mohammed S; Jacob, Joan; Merchant, Sana; Meade, Rachel K; Gahnim, Nagham M; Nawas, Afshan F; Xing, Chao; Delk, Nikki A

2018-06-01

In immunosurveillance, bone-derived immune cells infiltrate the tumor and secrete inflammatory cytokines to destroy cancer cells. However, cancer cells have evolved mechanisms to usurp inflammatory cytokines to promote tumor progression. In particular, the inflammatory cytokine, interleukin-1 (IL-1), is elevated in prostate cancer (PCa) patient tissue and serum, and promotes PCa bone metastasis. IL-1 also represses androgen receptor (AR) accumulation and activity in PCa cells, yet the cells remain viable and tumorigenic; suggesting that IL-1 may also contribute to AR-targeted therapy resistance. Furthermore, IL-1 and AR protein levels negatively correlate in PCa tumor cells. Taken together, we hypothesize that IL-1 reprograms AR positive (AR + ) PCa cells into AR negative (AR - ) PCa cells that co-opt IL-1 signaling to ensure AR-independent survival and tumor progression in the inflammatory tumor microenvironment. LNCaP and PC3 PCa cells were treated with IL-1β or HS-5 bone marrow stromal cell (BMSC) conditioned medium and analyzed by RNA sequencing and RT-QPCR. To verify genes identified by RNA sequencing, LNCaP, MDA-PCa-2b, PC3, and DU145 PCa cell lines were treated with the IL-1 family members, IL-1α or IL-1β, or exposed to HS-5 BMSC in the presence or absence of Interleukin-1 Receptor Antagonist (IL-1RA). Treated cells were analyzed by western blot and/or RT-QPCR. Comparative analysis of sequencing data from the AR + LNCaP PCa cell line versus the AR - PC3 PCa cell line reveals an IL-1-conferred gene suite in LNCaP cells that is constitutive in PC3 cells. Bioinformatics analysis of the IL-1 regulated gene suite revealed that inflammatory and immune response pathways are primarily elicited; likely facilitating PCa cell survival and tumorigenicity in an inflammatory tumor microenvironment. Our data supports that IL-1 reprograms AR + PCa cells to mimic AR - PCa gene expression patterns that favor AR-targeted treatment resistance and cell survival. © 2018 Wiley

75 FR 12165 - Class E Airspace; Batesville, AR

Science.gov (United States)

2010-03-15

...-1177; Airspace Docket No. 09-ASW-34] Class E Airspace; Batesville, AR AGENCY: Federal Aviation... Class E airspace at Batesville, AR. Decommissioning of the Independence County non-directional beacon... for standard instrument approach procedures at Batesville Regional Airport, Batesville, AR. Airspace...

37Ar monitoring techniques and on-site inspection system

International Nuclear Information System (INIS)

Duan Rongliang; Chen Yinliang; Li Wei; Wang Hongxia; Hao Fanhua

2001-01-01

37 Ar is separated, purified and extracted from air sample with a low temperature gas-solid chromatographic purifying method, prepared into a radioactive measurement source and its radioactivity is measured with a proportional counter. Based on the monitoring result, a judgement can be made if an nuclear explosion event has happened recently in a spectabilis area. A series of element techniques that are associated the monitoring of the trace element 37 Ar have been investigated and developed. Those techniques include leaked gas sampling, 37 Ar separation and purification, 37 Ar radioactivity measurement and the on-site inspection of 37 Ar. An advanced 37 Ar monitoring method has been developed, with which 200 liters of air can be treated in 2 hours with sensitivity of 0.01 Bq/L for 37 Ar radioactivity measurement. A practical 37 Ar On-site Inspection system has been developed. This research work may provide technical and equipment support for the verification protection, verification supervision and CTBT verification

I-Xe and 40Ar-39Ar analyses of silicate from the Eagle Station pallasite and the anomalous iron meteorite Enon

International Nuclear Information System (INIS)

Niemeyer, S.

1983-01-01

Silicate from two unusual iron-rich meteorites were analyzed by the I-Xe and 40 Ar- 39 Ar techniques. Enon, an anomalous iron meteorite with chondritic silicate, shows no loss of radiogenic 40 Ar at low temperature, and gives a plateau age of 4.59 +- 0.03 Ga. Although the Xe data fail to define an I-Xe correlation the inferred Pu/U ratio is more than 2 σ above the chondritic value, and the Pu abundance derived from the concentration of Pu-fission Xe is 6 times greater than the abundance inferred for CI meteorites. These findings for Enon, coupled with data for IAB iron meteorites, suggest that presence of chondritic silicate in an iron-rich meteorite is diagnostic of an old radiometric age with little subsequent thermal disturbance. The Eagle Station pallasite, the most 16 O-rich meteorite known, gives a complex 40 Ar- 39 Ar age pattern which suggests a recent severe thermal disturbance. The absence of excess 129 Xe, and the low trapped Ar and Xe contents, are consistent with this interpretation. The similarity between 40 Ar- 39 Ar data for Eagle Station and for the olivine-rich meteorite Chassigny lends credence to the previous suggestion of a connection between Chassigny and pallasites. (author)

Near thermal charge transfer between Ar+2 and N2

International Nuclear Information System (INIS)

Holzscheiter, H.M.; Church, D.A.

1981-01-01

The near thermal charge transfer reaction of Ar +2 with N 2 has been studied at total pressures below 10 -7 Torr using a stored ion technique. Ar +2 ions produced by electron impact double ionization of Ar gas were selectively stored for times the order of seconds in a split-ring Penning-type ion trap. The decay with time of the initial ion sample number in a mixture of Ar and N 2 gases was fit to the sum of two exponentials, corresponding to different reaction rates for the 3 P and 1 D low-lying Ar +2 levels. The observed Ar +2 number decrease is attributed to the double-charge transfer process Ar +2 +N 2 →Ar+N 2 +2 →Ar+N + +N + in accord with recent flow-tube measurements. A rate constant for the metastable Ar +2 ( 1 D) level reaction with a value k( 1 D)=1.4 x 10 -9 cm 3 /sec is obtained, using the previously measured rate constant for the Ar +2 ( 3 P) state

40Ar/39Ar geochronology and geochemical reconnaissance of the Eocene Lowland Creek volcanic field, west-central Montana

Science.gov (United States)

Dudas, F.O.; Ispolatov, V.O.; Harlan, S.S.; Snee, L.W.

2010-01-01

We report geochronological and geochemical data for the calc-alkalic Lowland Creek volcanic field (LCVF) in westcentral Montana. 40Ar/ 39Ar age determinations show that the LCVF was active from 52.9 to 48.6 Ma, with tuff-forming eruptions at 52.9 ?? 0.14 and 51.8 ?? 0.14 Ma. These dates span the age range of vigorous Eocene igneous activity in the Kamloops-Absaroka-Challis belt. The LCVF evolved upward from basal rhyolites (SiO 2>71 wt%) to dacites and andesites (SiO 2 > 62 wt%). Compositional change parallels a transition from early explosive volcanism to late effusive activity. Four geochemical components can be detected in the rocks. A component with 206Pb/204Pb 18.3 and epsilon;Nd>-9 contain a third component; and an andesite with low Nd content and epsilon;Nd near-9 probably contains a fourth component. The first three components probably derive from the lower and middle crust, whereas the fourth is probably from the lithospheric mantle. ?? 2010 by The University of Chicago.

Ar-37 in the Atmospheric and Sub-Soil Gases

International Nuclear Information System (INIS)

Purtschert, R.; Raghoo, L.S.

2015-01-01

On-site inspection of the radioactive noble gas isotope 37Ar is a definitive and unambiguous indicator of an underground nuclear explosion. 37Ar is produced underground by neutron activation of calcium by the reaction 40Ca(n,α)37Ar. In the atmosphere, 37Ar is produced by the spallation reaction 40Ar(n,4n)37Ar. Periodic measurements over the last six years on air collected in Bern revealed a background level in the order of 1-5 mBq/m 3 air in agreement with former findings and theoretical calculations. Those calculations also indicated that the intrusion of stratospheric air masses may lead to elevated tropospheric 37Ar concentrations up to 8-10 mBq/m 3 air. Selected samples taken up to now in the vicinity of nuclear power plants revealed no significant deviation from the natural background. In order to distinguish between natural and artificially elevated 37Ar the location-specific 37Ar activity range in soils, rocks and the atmosphere were identified. From CARIBIC flights, a passenger aircraft with a special air freight container filled with scientific equipment in the cargo compartment, tropospheric air samples were analyzed for 37Ar and 85Kr. The natural 37Ar production in soils and the rock basement underlying the alluvium is investigated by means of in situ measurements of different isotopes, theoretical calculations and irradiation experiments on selected rock samples. This will help resolve the temporal evolution and/or constancy of the natural 37Ar background and allow for an interpretation in terms of the identification of clandestine nuclear explosions. (author)

Targeting AR Variant-Coactivator Interactions to Exploit Prostate Cancer Vulnerabilities.

Science.gov (United States)

Magani, Fiorella; Peacock, Stephanie O; Rice, Meghan A; Martinez, Maria J; Greene, Ann M; Magani, Pablo S; Lyles, Rolando; Weitz, Jonathan R; Burnstein, Kerry L

2017-11-01

Castration-resistant prostate cancer (CRPC) progresses rapidly and is incurable. Constitutively active androgen receptor splice variants (AR-Vs) represent a well-established mechanism of therapeutic resistance and disease progression. These variants lack the AR ligand-binding domain and, as such, are not inhibited by androgen deprivation therapy (ADT), which is the standard systemic approach for advanced prostate cancer. Signaling by AR-Vs, including the clinically relevant AR-V7, is augmented by Vav3, an established AR coactivator in CRPC. Using mutational and biochemical studies, we demonstrated that the Vav3 Diffuse B-cell lymphoma homology (DH) domain interacted with the N-terminal region of AR-V7 (and full length AR). Expression of the Vav3 DH domain disrupted Vav3 interaction with and enhancement of AR-V7 activity. The Vav3 DH domain also disrupted AR-V7 interaction with other AR coactivators: Src1 and Vav2, which are overexpressed in PC. This Vav3 domain was used in proof-of-concept studies to evaluate the effects of disrupting the interaction between AR-V7 and its coactivators on CRPC cells. This disruption decreased CRPC cell proliferation and anchorage-independent growth, caused increased apoptosis, decreased migration, and resulted in the acquisition of morphological changes associated with a less aggressive phenotype. While disrupting the interaction between FL-AR and its coactivators decreased N-C terminal interaction, disrupting the interaction of AR-V7 with its coactivators decreased AR-V7 nuclear levels. Implications: This study demonstrates the potential therapeutic utility of inhibiting constitutively active AR-V signaling by disrupting coactivator binding. Such an approach is significant, as AR-Vs are emerging as important drivers of CRPC that are particularly recalcitrant to current therapies. Mol Cancer Res; 15(11); 1469-80. ©2017 AACR . ©2017 American Association for Cancer Research.

40Ar/39Ar geochronology at the Instituto de Geociências, USP: instrumentation, analytical procedures, and calibration

Directory of Open Access Journals (Sweden)

PAULO M. VASCONCELOS

2002-06-01

Full Text Available Laser heating 40Ar/39Ar geochronology provides high analytical precision and accuracy, mum-scale spatial resolution, and statistically significant data sets for the study of geological and planetary processes. A newly commissioned 40Ar/39Ar laboratory at CPGeo/USP, São Paulo, Brazil, equips the Brazilian scientific community with a new powerful tool applicable to the study of geological and cosmochemical processes. Detailed information about laboratory layout, environmental conditions, and instrumentation provides the necessary parameters for the evaluation of the CPGeo/USP 40Ar/39Ar suitability to a diverse range of applications. Details about analytical procedures, including mineral separation, irradiation at the IPEN/CNEN reactor at USP, and mass spectrometric analysis enable potential researchers to design the necessary sampling and sample preparation program suitable to the objectives of their study. Finally, the results of calibration tests using Ca and K salts and glasses, international mineral standards, and in-house mineral standards show that the accuracy and precision obtained at the 40Ar/39Ar laboratory at CPGeo/USP are comparable to results obtained in the most respected laboratories internationally. The extensive calibration and standardization procedures undertaken ensure that the results of analytical studies carried out in our laboratories will gain immediate international credibility, enabling Brazilian students and scientists to conduct forefront research in earth and planetary sciences.A geocronologia de 40Ar/39Ar por aquecimento a laser permite alta precisão e acurácia analítica, tem resolução espacial em escala micrométrica, e fornece um número de dados estatisticamente significantes para o estudo de processos geológicos e planetários. Um recém construído laboratório de 40Ar/39Ar no CPGeo/USP, São Paulo, Brazil, mune a sociedade científica brasileira com uma técnica eficaz aplicável aos estudos geol

Acute Radiation Syndrome (ARS) and its harmful effects on human health

International Nuclear Information System (INIS)

Khanam, Yasmin; Singh, Yogender

2012-01-01

After radiation exposure a series of many clinical syndromes appear that is called as Acute Radiation Syndrome (ARS). ARS also known as radiation toxicology or radiation sickness. Both low and higher doses radiation exposure on human body cause different types of radiation syndromes. These radiations may be ionizing radiations. X-rays and gamma rays etc. some times neutrons or radionuclides may also be deposited in human body and their effective doses cause major injuries or abnormalities even sometimes death also. ARS consist of a sequence of phased symptoms. These symptoms appear after the radiation exposure for several days to several months or sometimes for a long period or years. ARS depends on the quantity of absorbed radiation dose (rad0). ARS is characterized by an initial prodromal stage of malaise, nausea, vomiting, and diarrhea. Critical effects of ARS are Hematologic, that results infections to low white blood cells (WBC), bleeding due to low platelets and anemia due to low red blood cells (RBC), Gastrointestinal results nausea, vomiting, loss of appetite and abdominal pain (exposure doses of 600-1000 rad) and Neurovascular depending on the exposure dose. Neurovascular syndrome typically occurs at exposure doses greater than 1000 rad. It presents with neurological symptoms such as dizziness, headache, or decreased level of consciousness with an absence of vomiting. The clinical course of radiation sickness following a single intensive exposure to whole body radiation is characterized by three successive phases; a prodromal phase, which develops within minutes or hours after exposure, an ensuring latent period, which is relatively asymptomatic; and the main phase of the illness. Complete Blood Count (CBC) are helpful for the diagnosis for ARS. ARS may cause skin damage or loss of epidermis. Person suffering from nausea, vomiting, diarrhea should be admitted to well equipped hospitals or clinics. High exposured persons should be analysed CBC. Their

75 FR 12162 - Class E Airspace; Manila, AR

Science.gov (United States)

2010-03-15

...-1184; Airspace Docket No. 09-ASW-39] Class E Airspace; Manila, AR AGENCY: Federal Aviation... Class E airspace at Manila, AR. Decommissioning of the Manila non-directional beacon (NDB) at Manila... instrument approach procedures at Manila Municipal Airport, Manila, AR. Airspace reconfiguration is necessary...

Effects of lamellae size distributions from 40Ar/39Ar on sedimentary thermo-chronology in the San Joaquin Basin

International Nuclear Information System (INIS)

Jepsen, A.-M.; Lerche, I.; Thomsen, R.O.

1990-01-01

A model description is provided for the release of 40 Ar/ 39 Ar from detrital microclines which specifically includes the effects of grain size distributions, thus allowing smaller grains to release argon faster than the more retentive larger grains. The model also includes the effects of sedimentary thermal history after burial influencing the pre-depositional 40 Ar/ 30 Ar ratio. Application of the model to the measured age spectra from six depths in the Tejon Block and four in the Basin Block of the San Joaquin Basin demonstrates that the grain size distribution effect plays a major role in masking the extraction of thermal history information from the observed age spectra. In addition, the grain size effect is not systematic with depth, and other competing effects, such as isotopic fractionation of diffusion coefficients, multi-provenance depositional supply, and variable concentrations of 40 Ar and 39 K per microcline at burial deposition time, make the extraction of thermal history information even more difficult. (author)

An 40 Ar- 39 Ar study of the Cape Verde hot spot

DEFF Research Database (Denmark)

Holm, Paul Martin; Grandvuinet, Tanja; Wilson, James Richard

2008-01-01

The 40Ar-39Ar analyses of 28 groundmass separates from volcanic rocks from the islands of Santiago, Sal, and São Vicente, Cape Verde archipelago, are presented. The new age data record the volcanic evolution for Santiago from 4.6 to 0.7 Ma, for Sal from around 15 to 1.1 Ma, and for São Vicente from...... Cretaceous age for limestones deposited on the seafloor and later uplifted. The Cape Verde Rise is indicated to have fully formed in the early Miocene around 22 Ma, accompanied by the initial alkaline volcanism. Considerable volcanism on Sal, Boa Vista, and Maio took place in the Miocene and Pliocene...

Characterization of novel StAR (steroidogenic acute regulatory protein mutations causing non-classic lipoid adrenal hyperplasia.

Directory of Open Access Journals (Sweden)

Christa E Flück

Full Text Available CONTEXT: Steroidogenic acute regulatory protein (StAR is crucial for transport of cholesterol to mitochondria where biosynthesis of steroids is initiated. Loss of StAR function causes lipoid congenital adrenal hyperplasia (LCAH. OBJECTIVE: StAR gene mutations causing partial loss of function manifest atypical and may be mistaken as familial glucocorticoid deficiency. Only a few mutations have been reported. DESIGN: To report clinical, biochemical, genetic, protein structure and functional data on two novel StAR mutations, and to compare them with published literature. SETTING: Collaboration between the University Children's Hospital Bern, Switzerland, and the CIBERER, Hospital Vall d'Hebron, Autonomous University, Barcelona, Spain. PATIENTS: Two subjects of a non-consanguineous Caucasian family were studied. The 46,XX phenotypic normal female was diagnosed with adrenal insufficiency at the age of 10 months, had normal pubertal development and still has no signs of hypergonodatropic hypogonadism at 32 years of age. Her 46,XY brother was born with normal male external genitalia and was diagnosed with adrenal insufficiency at 14 months. Puberty was normal and no signs of hypergonadotropic hypogonadism are present at 29 years of age. RESULTS: StAR gene analysis revealed two novel compound heterozygote mutations T44HfsX3 and G221S. T44HfsX3 is a loss-of-function StAR mutation. G221S retains partial activity (∼30% and is therefore responsible for a milder, non-classic phenotype. G221S is located in the cholesterol binding pocket and seems to alter binding/release of cholesterol. CONCLUSIONS: StAR mutations located in the cholesterol binding pocket (V187M, R188C, R192C, G221D/S seem to cause non-classic lipoid CAH. Accuracy of genotype-phenotype prediction by in vitro testing may vary with the assays employed.

Defect production in Ar irradiated graphene membranes under different initial applied strains

Energy Technology Data Exchange (ETDEWEB)

Martinez-Asencio, J., E-mail: jesusmartinez@ua.es [Dept. Física Aplicada, Facultad de Ciencias, Fase II, Universidad de Alicante, Alicante E-036090 (Spain); Ruestes, C.J.; Bringa, E. [CONICET and Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza 5500 (Argentina); Caturla, M.J. [Dept. Física Aplicada, Facultad de Ciencias, Fase II, Universidad de Alicante, Alicante E-036090 (Spain)

2017-02-15

Highlights: • Defects in graphene membranes are formed due to 140 eV Ar ions irradiation using MD. • Different initial strains are applied, which influence the type and number of defects. • Mono-vacancies, di-vacancies and tri-vacancies production behaves linearly with dose. • The total number of defects under compression is slightly higher than under tension. - Abstract: Irradiation with low energy Ar ions of graphene membranes gives rise to changes in the mechanical properties of this material. These changes have been associated to the production of defects, mostly isolated vacancies. However, the initial state of the graphene membrane can also affect its mechanical response. Using molecular dynamics simulations we have studied defect production in graphene membranes irradiated with 140 eV Ar ions up to a dose of 0.075 × 10{sup 14} ions/cm{sup 2} and different initial strains, from −0.25% (compressive strain) to 0.25% (tensile strain). For all strains, the number of defects increases linearly with dose with a defect production of about 80% (80 defects every 100 ions). Defects are mostly single vacancies and di-vacancies, although some higher order clusters are also observed. Two different types of di-vacancies have been identified, the most common one being two vacancies at first nearest neighbours distance. Differences in the total number of defects with the applied strain are observed which is related to the production of a higher number of di-vacancies under compressive strain compared to tensile strain. We attribute this effect to the larger out-of-plane deformations of compressed samples that could favor the production of defects in closer proximity to others.

Emission and absorption spectroscopy study of Ar excited states in 13.56 MHz argon plasma operating at sub-atmospheric to atmospheric pressure

Energy Technology Data Exchange (ETDEWEB)

Li, L. [Department of Applied Physics, Research Unit Plasma Technology, Ghent University, Jozef Plateaustraat 22, Ghent B-9000 (Belgium); Nikiforov, A., E-mail: anton.nikiforov@ugent.be [Department of Applied Physics, Research Unit Plasma Technology, Ghent University, Jozef Plateaustraat 22, Ghent B-9000 (Belgium); Institute of Solution Chemistry of the Russian Academy of Science, Academicheskaya St., 1, Ivanovo, 153045 (Russian Federation); Britun, N. [Chimie des Interactions Plasma-Surface (ChIPS), CIRMAP, Universite de Mons, 23 Place du Parc, B-7000 Mons (Belgium); Snyders, R. [Chimie des Interactions Plasma-Surface (ChIPS), CIRMAP, Universite de Mons, 23 Place du Parc, B-7000 Mons (Belgium); Materia Nova Research Centre, Parc Initialis, B-7000 Mons (Belgium); Leys, C. [Department of Applied Physics, Research Unit Plasma Technology, Ghent University, Jozef Plateaustraat 22, Ghent B-9000 (Belgium)

2015-05-01

The densities of metastable and resonant states of Ar atoms are measured in high pressure Ar radio frequency discharge. Resonant absorption spectroscopy for the case of a low pressure spectral lamp and high-pressure plasma absorption lines is implemented for this purpose. The necessary generalizations for the high-pressure resonant absorption method are given. Absolute density of Ar 1s levels obtained at different RF input power and operating pressures are of the order of 10{sup 11} cm{sup −3}, which is in a good agreement with those reported in the literature. The population distribution on the Ar 2p (excited) levels, obtained from the optical emission spectroscopy, reveals strong deviation from thermal equilibrium for these levels in the high-pressure case. The generation of the Ar excited states in the studied discharges is compared to the previously reported results. - Highlights: • Strong non-equilibrium distribution of Ar 2p levels is observed. • The absolute number density of non-radiative Ar 1s states is determined by the easier and low cost spectral-lamp absorption method. • The modified absorption theory of Mitchell and Zemanski was used to obtain the absolute number density of Ar 1s states at high pressure. • The developed RF source with 5 cm long gap can be a possible alternative to micro-plasma working in Ar at atmospheric pressure.

Measurements and calculations for determination of discharge of 41Ar from IFEs research reactor JEEP II at Kjeller, Norway

International Nuclear Information System (INIS)

Raaum, A.; Straelberg, E.

2003-01-01

41 Ar is formed by neutron irradiation of 40 Ar, which occurs naturally in air with a concentration of 9300 ppm. The discharge of 41 Ar from IFEs research reactor Jeep II is yearly reported to the Norwegian Radiation Protection Authority (NRPA). Until year 2000 the reported values were based on theoretical calculations of produced 41 Ar per operating hour of 6.8 GBq/h. During 2000 and 2001 the reactor was upgraded to increase the irradiation capacity and to meet the markets demand for irradiation of 5'Si-crystalls. After the upgrading, measurements and calculations were initiated to determine the new discharge rate for 41 Ar. During reactor operation an approximately constant discharge of 41 Ar is expected, mainly due to irradiation of air in open beam channels. In addition 41 Ar is released from irradiation pockets when they are opened to transfer samples in and out during reactor stop. The new value for discharge rate was determined from measurements of air samples from the discharge channel during operation and theoretical calculations of the release from the irradiation pockets. The new discharge rate was determined to 5.9 ± 0.5 GBq/h, which is a small reduction compared to the former value of 6.8 GBq/h. A small reduction in discharge rate was expected because the number of air-filled irradiation pockets was reduced after the upgrading. In a normal year the discharge of 41 Ar will be about 2 % of the Institutes discharge permission. (orig.)

Molecular dynamics study of the effect of substrate temperature and Ar ion assisted deposition on the deposition of amorphous TiO_2 films

International Nuclear Information System (INIS)

Chen, Xian; Zhang, Jing; Zhao, Yu-Qing

2017-01-01

Highlights: • The surface roughness of a-TiO_2 films is decreased with the increment of the Ar ion assisted energy. • The surface roughness of a-TiO_2 films is decreased with higher substrate temperature when the substrate has an island structure. • The assisted Ar ion has power of making a flat surface and increasing the local temperature. • The assisted Ar ion will influence the growth mode with the change of surface atom mobility. • The Volmer-Weber (island) growth mode is inhibited with a high assisted Ar ion energy. - Abstract: This paper has investigated the impact of the substrate temperature and Ar ion assisted deposition on the surface structure formation mechanism and the film properties during the amorphous TiO_2 thin film deposition process with the molecular dynamics simulation method. The results show that the reduction of the surface roughness happen when the energy of Ar ions assisted is increased or the substrate temperature rises, and also the film density on surface is changed with the increasing of Ar ions energy and substrate temperature. It is also found that the Volmer-Weber (island) growth mode of films is promoted by the lower Ar ion energy and higher substrate temperature when the substrate has an island structure. The assisted Ar ion has power of making a flat surface and increasing the local temperature. Besides, it will influence the growth mode with the change of surface atom mobility. With a high assisted Ar ion energy the Volmer-Weber (island) growth mode is inhibited, which will be conducive to the formation of more smooth film surface.

Confirming the key role of Ar+ ion bombardment in the growth feature of nanostructured carbon materials by PECVD

Science.gov (United States)

Liu, Yulin; Lin, Jinghuang; Jia, Henan; Chen, Shulin; Qi, Junlei; Qu, Chaoqun; Cao, Jian; Feng, Jicai; Fei, Weidong

2017-11-01

In order to confirm the key role of Ar+ ion bombardment in the growth feature of nanostructured carbon materials (NCMs), here we report a novel strategy to create different Ar+ ion states in situ in plasma enhanced chemical vapor deposition (PECVD) by separating catalyst film from the substrate. Different bombardment environments on either side of the catalyst film were created simultaneously to achieve multi-layered structural NCMs. Results showed that Ar+ ion bombardment is crucial and complex for the growth of NCMs. Firstly, Ar+ ion bombardment has both positive and negative effects on carbon nanotubes (CNTs). On one hand, Ar+ ions can break up the graphic structure of CNTs and suppress thin CNT nucleation and growth. On the other hand, Ar+ ion bombardment can remove redundant carbon layers on the surface of large catalyst particles which is essential for thick CNTs. As a result, the diameter of the CNTs depends on the Ar+ ion state. As for vertically oriented few-layer graphene (VFG), Ar+ ions are essential and can even convert the CNTs into VFG. Therefore, by combining with the catalyst separation method, specific or multi-layered structural NCMs can be obtained by PECVD only by changing the intensity of Ar+ ion bombardment, and these special NCMs are promising in many fields.

Confirming the key role of Ar+ ion bombardment in the growth feature of nanostructured carbon materials by PECVD.

Science.gov (United States)

Liu, Yulin; Lin, Jinghuang; Jia, Henan; Chen, Shulin; Qi, Junlei; Qu, Chaoqun; Cao, Jian; Feng, Jicai; Fei, Weidong

2017-11-24

In order to confirm the key role of Ar + ion bombardment in the growth feature of nanostructured carbon materials (NCMs), here we report a novel strategy to create different Ar + ion states in situ in plasma enhanced chemical vapor deposition (PECVD) by separating catalyst film from the substrate. Different bombardment environments on either side of the catalyst film were created simultaneously to achieve multi-layered structural NCMs. Results showed that Ar + ion bombardment is crucial and complex for the growth of NCMs. Firstly, Ar + ion bombardment has both positive and negative effects on carbon nanotubes (CNTs). On one hand, Ar + ions can break up the graphic structure of CNTs and suppress thin CNT nucleation and growth. On the other hand, Ar + ion bombardment can remove redundant carbon layers on the surface of large catalyst particles which is essential for thick CNTs. As a result, the diameter of the CNTs depends on the Ar + ion state. As for vertically oriented few-layer graphene (VFG), Ar + ions are essential and can even convert the CNTs into VFG. Therefore, by combining with the catalyst separation method, specific or multi-layered structural NCMs can be obtained by PECVD only by changing the intensity of Ar + ion bombardment, and these special NCMs are promising in many fields.

Fenofibrate down-regulates the expressions of androgen receptor (AR) and AR target genes and induces oxidative stress in the prostate cancer cell line LNCaP

Energy Technology Data Exchange (ETDEWEB)

Zhao, Hu; Zhu, Chen; Qin, Chao [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Tao, Tao [Department of Neurosurgery, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Li, Jie; Cheng, Gong; Li, Pu; Cao, Qiang; Meng, Xiaoxin; Ju, Xiaobing; Shao, Pengfei; Hua, Lixin [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Gu, Min, E-mail: medzhao1980@163.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China); Yin, Changjun, E-mail: drcjyin@gmail.com [State Key Laboratory of Reproductive Medicine, Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing (China)

2013-03-08

Highlights: ► Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells. ► Fenofibrate reduces the expressions of androgen receptor in LNCaP cells. ► Fenofibrate induces oxidative stress in the prostate cancer cell line LNCaP. -- Abstract: Fenofibrate, a peroxisome proliferator-androgen receptor-alpha agonist, is widely used in treating different forms of hyperlipidemia and hypercholesterolemia. Recent reports have indicated that fenofibrate exerts anti-proliferative and pro-apoptotic properties. This study aims to investigate the effects of fenofibrate on the prostate cancer (PCa) cell line LNCaP. The effects of fenofibrate on LNCaP cells were evaluated by flow cytometry, reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assays, Western blot analysis, and dual-luciferase reporter assay. Fenofibrate induces cell cycle arrest in G1 phase and apoptosis in LNCaP cells, reduces the expressions of androgen receptor (AR) and AR target genes (prostate-specific antigen and TMPRSS2), and inhibits Akt phosphorylation. Fenofibrate can induce the accumulation of intracellular reactive oxygen species and malondialdehyde, and decrease the activities of total anti-oxidant and superoxide dismutase in LNCaP cells. Fenofibrate exerts an anti-proliferative property by inhibiting the expression of AR and induces apoptosis by causing oxidative stress. Therefore, our data suggest fenofibrate may have beneficial effects in fenofibrate users by preventing prostate cancer growth through inhibition of androgen activation and expression.

The development of AR book for computer learning

Science.gov (United States)

Phadung, Muneeroh; Wani, Najela; Tongmnee, Nur-aiynee

2017-08-01

Educators need to provide the alternative educational tools to foster learning outcomes of students. By using AR technology to create exciting edutainment experiences, this paper presents how augmented reality (AR) can be applied in the education. This study aims to develop the AR book for tenth grade students (age 15-16) and evaluate its quality. The AR book was developed based on ADDIE framework processes to provide computer learning on software computer knowledge. The content was accorded with the current Thai education curriculum. The AR book had 10 pages in three topics (the first was "Introduction," the second was "System Software" and the third was "Application Software"). Each page contained markers that placed virtual objects (2D animation and video clip). The obtained data were analyzed in terms of average and standard deviation. The validity of multimedia design of the AR book was assessed by three experts in multimedia design. A five-point Likert scale was used and the values were X¯ =4 .84 , S.D. = 1.27 which referred to very high. Moreover, three content experts, who specialize in computer teaching, evaluated the AR book's validity. The values determined by the experts were X¯ =4 .69 , S.D. = 0.29 which referred to very high. Implications for future study and education are discussed.

ONC201 Targets AR and AR-V7 Signaling, Reduces PSA, and Synergizes with Everolimus in Prostate Cancer.

Science.gov (United States)

Lev, Avital; Lulla, Amriti R; Ross, Brian C; Ralff, Marie D; Makhov, Petr B; Dicker, David T; El-Deiry, Wafik S

2018-05-01

Androgen receptor (AR) signaling plays a key role in prostate cancer progression, and androgen deprivation therapy (ADT) is a mainstay clinical treatment regimen for patients with advanced disease. Unfortunately, most prostate cancers eventually become androgen-independent and resistant to ADT with patients progressing to metastatic castration-resistant prostate cancer (mCRPC). Constitutively activated AR variants (AR-V) have emerged as mediators of resistance to AR-targeted therapy and the progression of mCRPC, and they represent an important therapeutic target. Out of at least 15 AR-Vs described thus far, AR-V7 is the most abundant, and its expression correlates with ADT resistance. ONC201/TIC10 is the founding member of the imipridone class of small molecules and has shown anticancer activity in a broad range of tumor types. ONC201 is currently being tested in phase I/II clinical trials for advanced solid tumors, including mCRPC, and hematologic malignancies. There has been promising activity observed in patients in early clinical testing. This study demonstrates preclinical single-agent efficacy of ONC201 using in vitro and in vivo models of prostate cancer. ONC201 has potent antiproliferative and proapoptotic effects in both castration-resistant and -sensitive prostate cancer cells. Furthermore, the data demonstrate that ONC201 downregulates the expression of key drivers of prostate cancer such as AR-V7 and downstream target genes including the clinically used biomarker PSA (KLK3). Finally, the data also provide a preclinical rationale for combination of ONC201 with approved therapeutics for prostate cancer such as enzalutamide, everolimus (mTOR inhibitor), or docetaxel. Implications: The preclinical efficacy of ONC201 as a single agent or in combination, in hormone-sensitive or castration-resistant prostate cancer, suggests the potential for immediate clinical translation. Mol Cancer Res; 16(5); 754-66. ©2018 AACR . ©2018 American Association for Cancer

AR Signaling in Human Malignancies: Prostate Cancer and Beyond.

Science.gov (United States)

Antonarakis, Emmanuel S

2018-01-18

The notion that androgens and androgen receptor (AR) signaling are the hallmarks of prostate cancer oncogenesis and disease progression is generally well accepted. What is more poorly understood is the role of AR signaling in other human malignancies. This special issue of Cancers initially reviews the role of AR in advanced prostate cancer, and then explores the potential importance of AR signaling in other epithelial malignancies. The first few articles focus on the use of novel AR-targeting therapies in castration-resistant prostate cancer and the mechanisms of resistance to novel antiandrogens, and they also outline the interaction between AR and other cellular pathways, including PI3 kinase signaling, transcriptional regulation, angiogenesis, stromal factors, Wnt signaling, and epigenetic regulation in prostate cancer. The next several articles review the possible role of androgens and AR signaling in breast cancer, bladder cancer, salivary gland cancer, and hepatocellular carcinoma, as well as the potential treatment implications of using antiandrogen therapies in these non-prostatic malignancies.

Molecular dynamic simulation of interaction of low-energy Ar and Xe ions with copper clusters at graphite surface

International Nuclear Information System (INIS)

Kornich, G.V.; Lozovskaya, L.I.; Betts, G.; Zaporozhchenko, V.I.; Faupel, F.

2005-01-01

One conducted molecular and dynamic simulation of sputtering of isolated clusters consisting of 13, 27 and 195 Cu atoms from the (0001) graphite surface by 200 eV energy Ar and Xe ions. It is shown that the factors of reflection of Ar and Xe ions from copper clusters differ from one another insignificantly, though the energy of the reflected Xe ions is essentially lower than that of Ar ions. The values of the factor of cluster sputtering by Xe ions are higher in contrast to sputtering by Ar ions. One identified two mechanisms of cluster sputtering resulting in the maximum of sputtering intensity at the polar angles near the normal one, and in periodicity of maximums within the azimuth distributions of sputtering intensity with 60 deg period [ru

Detection of anabolic androgenic steroid abuse in doping control using mammalian reporter gene bioassays.

Science.gov (United States)

Houtman, Corine J; Sterk, Saskia S; van de Heijning, Monique P M; Brouwer, Abraham; Stephany, Rainer W; van der Burg, Bart; Sonneveld, Edwin

2009-04-01

Anabolic androgenic steroids (AAS) are a class of steroid hormones related to the male hormone testosterone. They are frequently detected as drugs in sport doping control. Being similar to or derived from natural male hormones, AAS share the activation of the androgen receptor (AR) as common mechanism of action. The mammalian androgen responsive reporter gene assay (AR CALUX bioassay), measuring compounds interacting with the AR can be used for the analysis of AAS without the necessity of knowing their chemical structure beforehand, whereas current chemical-analytical approaches may have difficulty in detecting compounds with unknown structures, such as designer steroids. This study demonstrated that AAS prohibited in sports and potential designer AAS can be detected with this AR reporter gene assay, but that also additional steroid activities of AAS could be found using additional mammalian bioassays for other types of steroid hormones. Mixtures of AAS were found to behave additively in the AR reporter gene assay showing that it is possible to use this method for complex mixtures as are found in doping control samples, including mixtures that are a result of multi drug use. To test if mammalian reporter gene assays could be used for the detection of AAS in urine samples, background steroidal activities were measured. AAS-spiked urine samples, mimicking doping positive samples, showed significantly higher androgenic activities than unspiked samples. GC-MS analysis of endogenous androgens and AR reporter gene assay analysis of urine samples showed how a combined chemical-analytical and bioassay approach can be used to identify samples containing AAS. The results indicate that the AR reporter gene assay, in addition to chemical-analytical methods, can be a valuable tool for the analysis of AAS for doping control purposes.

Fusion-fission in Ar-heavy nuclei collisions

International Nuclear Information System (INIS)

Zaric, Alexandre

1984-01-01

Fusion-fission products have been studied for three reactions: Ar + Au, Ar + Bi and Ar + U (5.25-7.5 MeV/u). By measuring symmetric fragmentation components (fission-like events), cross sections for fusion were deduced and compared with the prediction of static and dynamic models. With increasing projectile energy, the width of the mass distributions strongly increases for the two lighter systems. By contrast, for Ar + U it remains essentially constant at a very large value. These results clearly demonstrate that the large increase of the width of the mass distribution cannot be attributed simply to large values of the angular momentum. However, they can be explained by the occurrence of a different dissipative process, fast fission, which can be expected if there is no barrier to fission. For the reaction Ar + Au, the total kinetic-energy distributions were also studied in detail. In this case fast fission occurs only at high incident energy. The average total kinetic energy (TKE) was found to be constant with increasing energy. (author) [fr

Electron temperatures of inductively coupled Cl2-Ar plasmas

International Nuclear Information System (INIS)

Fuller, N.C.M.; Donnelly, Vincent M.; Herman, Irving P.

2002-01-01

Trace rare gases optical emission spectroscopy has been used to measure the electron temperature, T e , in a high-density inductively coupled Cl 2 -Ar plasma at 18 mTorr as function of the 13.56 MHz radio frequency power and Ar fraction. Only the Kr and Xe emission lines were used to determine T e , because of evidence of radiation trapping when the Ar emission lines were also used for larger Ar fractions. At 600 W (10.6 W cm-2), T e increases from ∼4.0±0.5 eV to ∼6.0±2.0 eV as the Ar fraction increases from 1% to 96%. In the H (inductive, bright) mode, T e , for a 'neat' chlorine plasma (including 1% of each He/Ne/Ar/Kr/Xe) increases only slightly from ∼3.8 to 4.0 eV as power increases from 450 to 750 W. This increase is much larger for larger Ar fractions, such as from ∼4.0 to 7.3 eV for 78% Ar. Most of these effects can be understood using the fundamental particle balance equation

State-specific transport properties of electronically excited Ar and C

Science.gov (United States)

Istomin, V. A.; Kustova, E. V.

2018-05-01

In the present study, a theoretical model of state-resolved transport properties in electronically excited atomic species developed earlier is applied to argon and carbon atomic species. It is shown that for Ar and C, similarly to the case of atomic nitrogen and oxygen, the Slater-like models can be applied to calculate diameters of electronically excited atoms. Using the Slater-like model it is shown that for half-filled N (2 px1py1pz1) and full-filled Ar (3 px2py2pz2) electronic shells the growth of atomic radius goes slowly compared to C (2 px1py1) and O (2 px2py1pz1). The effect of collision diameters on the transport properties of Ar and C is evaluated. The influence of accounted number of electronic levels on the transport coefficients is examined for the case of Boltzmann distributions over electronic energy levels. It is emphasized that in the temperature range 1000-14000 K, for Boltzmann-like distributions over electronic states the number of accounted electronic levels do not influence the transport coefficients. Contrary to this, for higher temperatures T > 14000 K this effect becomes of importance, especially for argon.

New palynology-based astronomical and revised 40Ar/39Ar ages for the Eocene maar lake of Messel (Germany)

Science.gov (United States)

Lenz, Olaf K.; Wilde, Volker; Mertz, Dieter F.; Riegel, Walter

2015-04-01

The annually laminated oil shale from the Eocene maar lake at Messel (Federal State of Hessen, Germany) provides unique paleoenvironmental data for a time interval of ~640 ka during the Paleogene greenhouse phase. As a consequence of orbitally controlled changes in the vegetation in the vicinity of the lake, the lacustrine laminites can now be astronomically tuned. Dating is based on the short eccentricity amplitude modulations of the regional pollen rain and their correlation to the astronomical La2010a/La2010d solutions in combination with a revised 40Ar/39Ar age of a basalt fragment from a lapilli tuff section below the first lacustrine sediments. Depending on different newly suggested ages for the Fish Canyon sanidine used as monitor for neutron irradiation, the age for the eruption at Messel is between 48.27 ± 0.22 and 48.11 ± 0.22 Ma. This allows for the first time the exact correlation of a Paleogene lacustrine sequence to the marine record in Central Europe. The Messel oil shale becomes now slightly older than previously assumed and includes the Ypresian/Lutetian boundary that moves the base of the European Land Mammal Age Geiseltalian (MP 11) into the Lower Eocene. This opens a window for establishing an independent chronostratigraphic framework for Paleogene terrestrial records and their correlation to the marine realm. Furthermore, the study reveals that higher amounts of pollen from "wet" and thermophilous plants indicate less seasonal and more balanced precipitation and slightly higher temperatures during a well-expressed eccentricity minimum.

Anomalous evolution of Ar metastable density with electron density in high density Ar discharge

International Nuclear Information System (INIS)

Park, Min; Chang, Hong-Young; You, Shin-Jae; Kim, Jung-Hyung; Shin, Yong-Hyeon

2011-01-01

Recently, an anomalous evolution of argon metastable density with plasma discharge power (electron density) was reported [A. M. Daltrini, S. A. Moshkalev, T. J. Morgan, R. B. Piejak, and W. G. Graham, Appl. Phys. Lett. 92, 061504 (2008)]. Although the importance of the metastable atom and its density has been reported in a lot of literature, however, a basic physics behind the anomalous evolution of metastable density has not been clearly understood yet. In this study, we investigated a simple global model to elucidate the underlying physics of the anomalous evolution of argon metastable density with the electron density. On the basis of the proposed simple model, we reproduced the anomalous evolution of the metastable density and disclosed the detailed physics for the anomalous result. Drastic changes of dominant mechanisms for the population and depopulation processes of Ar metastable atoms with electron density, which take place even in relatively low electron density regime, is the clue to understand the result.

Light fragment production at forward angles in Ne and Ar induced reactions

International Nuclear Information System (INIS)

Alard, J.P.; Biagi, F.; Morel, P.; Bastid, N.; Augerat, J.; Charmensat, P.; Crouau, M.; Dupieux, P.; Fraysse, L.; Marroncle, J.; Brochard, F.; Gorodetzky, P.; Racca, C.

1990-01-01

The results of the experiments performed at Saturne, in order to investigate light fragment emission at small angles, are reported. The measurements were performed using a plastic wall associated with the Diogene pictorial drift chamber. Different selected multiplicities in the central chamber are applied. The exclusive measurements are reported both for Ne and Ar projectiles on several targets

Ars Electronica

DEFF Research Database (Denmark)

Kristensen, Thomas Bjørnsten

2009-01-01

Anmeldelse af Ars Electronica festivalen 3. - 8. september, 2009 i Linz, Østrig, der fejrede 30 års jubilæum under temaet "Human Nature". Festivalen fokuserer på interaktion mellem menneske, teknologi, kunst og samfund med særlig vægt på udviklingen af computeren og det digitale. Udgivelsesdato: 15.12...

Heterogeneous 40Ar/39Ar laser probe apparent ages in low-grade mylonitic rocks: Constraining a meaningful geological age

International Nuclear Information System (INIS)

Arancibia, G

2001-01-01

Obtaining meaningful geological ages from mylonitic rocks has been a major problem for structural geologist, because apparent ages have usually no geologic significance. Over the last years, in situ high spatial resolutions 40 Ar/ 39 Ar studies (e.g. Ruffet et al., 1991; Reddy et al., 1996; Pickles et al., 1997), permit obtain apparent ages of mineral and link them directly with textural, microstructural and chemical patterns that can previously be obtained by optical and scanning electron (SEM) microscopes and electron microprobe. In this work, heterogeneous 40 Ar/ 39 Ar laser probe ages from low-grade volcanic mylonites show complex argon distributions patterns. Inverse isochron analysis suggests that most obtained apparent ages contain argon excess and only younger ages have a meaningful geologically interpretation (au)

The ChArMEx database

Science.gov (United States)

Ferré, Hélène; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Cloché, Sophie; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mière, Arnaud; Ramage, Karim; Vermeulen, Anne; Boulanger, Damien

2015-04-01

The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters , intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services, such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between ICARE, IPSL and OMP data centers and has been set up in the framework of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. ChArMEx data, either produced or used by the project, are documented and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. The website offers the usual but user-friendly functionalities: data catalog, user registration procedure, search tool to select and access data... The metadata (data description) are standardized, and comply with international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). A Digital Object Identifier (DOI) assignement procedure allows to automatically register the datasets, in order to make them easier to access, cite, reuse and verify. At present, the ChArMEx database contains about 120 datasets, including more than 80 in situ datasets (2012, 2013 and 2014 summer campaigns, background monitoring station of Ersa...), 25 model output sets (dust model intercomparison, MEDCORDEX scenarios...), a high resolution emission inventory over the Mediterranean... Many in situ datasets

The search for Ar in the lunar atmosphere using the Lunar Reconnaissance Orbiter's LAMP instrument.

Science.gov (United States)

Cook, J. C.; Stern, S. A.; Feldman, P. D.; Gladstone, R.; Retherford, K. D.; Greathouse, T. K.; Grava, C.

2014-12-01

The Apollo 17 mass spectrometer, LACE, first measured mass 40 particles in the lunar atmosphere, and over a nine-month period, detected variations correlated with the lunar day (Hoffman et al., 1973, LPSC, 4, 2865). LACE detected a high particle density at dusk (0.6-1.0x104 cm-3), decreasing through the lunar night to a few hundred cm-3, then increasing rapidly before dawn to levels 2-4 times greater than at dusk. No daytime measurements were made due to instrument saturation. Given the LACE measurements' periodic nature, and the Ar abundance in lunar regolith samples (Kaiser, 1972, EPSL, 13, 387), it was concluded that mass 40 was likely due to Ar. Benna et al. (2014, LPSC, 45, 1535) recently reported that the Neutral Mass Spectrometer (NMS) aboard LADEE also detected Ar (mass 40) with similar diurnal profiles. We report on UV spectra of the lunar atmosphere as obtained by the Lunar Reconnaissance Orbiter (LRO). Aboard LRO is the UV-spectrograph, LAMP (Lyman Alpha Mapping Project), spanning the spectral range 575 to 1965 Å. LAMP is typically oriented toward the surface and has been mapping the Moon since September 2009. LAMP also observes the tenuous lunar atmosphere when the surface is in darkness, but the atmospheric column below LRO is illuminated. We have previously used nadir oriented twilight observations to examine the sparse lunar atmosphere (Feldman et al., 2012, Icarus, 221, 854; Cook et al., 2013, Icarus, 225, 681; Stern et al., 2013, Icarus, 226, 1210; Cook & Stern 2014, Icarus, 236, 48). In Cook et al., 2013, we reported an upper limit for Ar of 2.3x104 cm-3. Since then, we have collected additional data and refined our search method by focusing on the regions (near equator) and local times (dawn and dusk) where Ar has been reported previously. We have carefully considered effective area calibration and g-factor accuracies and find these to be unlikely explanations for the order of magnitude differences. We will report new results, which provide much

40Ar/39Ar dating and geochemistry of tholeiitic magmatism related to the early opening of the Central Atlantic rift

International Nuclear Information System (INIS)

Sebai, A.; Feraud, G.; Bertrand, H.; Hanes, J.

1991-01-01

Tholeiitic effusive and intrusive magnetism from Iberia, Morocco, Algeria and Mali, realted to the early opening of the Central Atlantic rift, was dated by the 40 Ar/ 39 Ar step-heating method. Four plateau ags, rangin from 203.7±2.7 to 197.1±1.8 Ma, were obtained on plagioclase from dykes from theTaoudenni area (Mali) and two lava flows from Morocco. The Messejana dyke (Iberia), which previously yielded discrepant conventional K-Ar dates, did not furnish any 40 Ar/ 39 Ar plateau dates. However, there is a clear inverse relationship between apparent age and K/Ca atio for gas fractions from a plagioclase separate (proportional to the alteration degree) which, combined with dates obtained on amphibole, biotite and pyroxene, allows us to determine an age of around 200 Ma for this body. These data, and those obtained on the Foum Zguid (Morocco) and the Ksi Ksou (Algeria) dykes, give evidence of a brief magmatic event (between 206 and 195 Ma ago) which affected a large area ca. 2500 km long. Trace-element modelling shows that most of these formations originated from a homogeneous, enriched, source material. Such a brief magmatic episode related to the opening of a continental rift is in agreement with findings in other magmatic provinces (e.g. the Deccan traps and the Red Sea rift, precisely dated by the 40 Ar/ 39 Ar method as well). (orig.)

Sm-Nd and Ar-Ar Studies of DHO 908 and 489: Implications for Lunar Crustal History

Science.gov (United States)

Nyquist, L. E.; Shih, C. Y.; Reese, Y. D.; Park, J.; Bogard, D. D.; Garrison, D. H.; Yamaguchi, A.

2011-01-01

It is widely assumed that ferroan anorthosites (FANs) formed as flotation cumulates on a global lunar magma ocean (LMO). A corollary is that all FANs are approximately contemporaneous and formed with the same initial Nd-143/Nd-144 ratio. Indeed, a whole rock isochron for selected FANs (and An93 anorthosite) yields an isochron age of 4.42 +/- 0.13 Ga and initial Nd-143/Nd-144, expressed in epsilon-units, of epsilon(sub Nd,CHUR) = 0.3+/-0.3 relative to the CHondritic Uniform Reservoir , or epsilon(sub Nd,HEDPB)=-0.6+/-0.3 relative to the HED Parent Body. These values are in good agreement with the age (T) = 4.47+/-0.07 Ga, and epsilon(sub Nd,HEDPB) =-0.6 +/- 0.5 for FAN 67075. We also have studied anorthositic clasts in the Dhofar 908 and 489 lunar highland meteorites containing clasts of magnesian anorthosites (MAN) with Mg# approximately 75. Because of their relatively high Mg#, magnesian anorthosites should have preceded most FANs in crystallization from the LMO if both are LMO products. Thus, it is important to determine whether the Nd-isotopic data of MAN and FAN are consistent with a co-magmatic origin. We previously reported Sm-Nd data for white clast Dho 908 WC. Mafic minerals in this clast were too small to be physically separated for an isochron. However, we estimated initial Nd-143/Nd-144 for the clast by combining its bulk ("whole rock") Sm-Nd data with an Ar-39-Ar-40 age of 4.42+/-.04 Ga. Here we report additional Sm-Nd data for bulk samples of Dho 908 and its pair Dho 489.

ARABIC LIGHT STEMMER (ARS

Directory of Open Access Journals (Sweden)

ASMA AL-OMARI

2014-12-01

Full Text Available Stemming is a main step used to process textual data. It is usually used in several types of applications such as: text mining, information retrieval (IR, and natural language processing (NLP. A major task in stemming is to standardize words; which can be achieved by reducing each word to its base (root or stem. Arabic stemming is not an easy task. Unlike other languages, Arabic language is a highly inflected language, since it uses many inflectional forms. Researchers are divided on the benefit of using stemming in fields of IR, NLP...etc., since in Arabic the morphological variants of a certain word are not always semantically related. The aim of this paper is to design and implement a new Arabic light stemmer (ARS which is not based on Arabic root patterns. Instead, it depends on well defined mathematical rules and several relations between letters. A series of tests were conducted on ARS stemmer to compare its effectiveness with the effectiveness of two other Arabic stemmers. Test shows clearly the effectiveness superiority of ARS compared to effectiveness of these two Arabic stemmers.

Low-k SiOCH Film Etching Process and Its Diagnostics Employing Ar/C5F10O/N2 Plasma

Science.gov (United States)

Nagai, Mikio; Hayashi, Takayuki; Hori, Masaru; Okamoto, Hidekazu

2006-09-01

We proposed an environmental harmonic etching gas of C5F10O (CF3CF2CF2OCFCF2), and demonstrated the etching of low-k SiOCH films employing a dual-frequency capacitively coupled etching system. Dissociative ionization cross sections for the electron impact ionizations of C5F10O and c-C4F8 gases have been measured by quadrupole mass spectroscopy (QMS). The dissociative ionization cross section of CF3+ from C5F10O gas was much higher than those of other ionic species, and 10 times higher than that of CF3+ from C4F8 gas. CF3+ is effective for increasing the etching rate of SiO2. As a result, the etching rate of SiOCH films using Ar/C5F10O/N2 plasma was about 1000 nm/min, which is much higher than that using Ar/C4F8/N2 plasma. The behaviours of fluorocarbon radicals in Ar/C5F10O/N2 plasma, which were measured by infrared diode laser absorption spectroscopy, were similar to those in Ar/C4F8/N2 plasma. The densities of CF and CF3 radicals were markedly decreased with increasing N2 flow rate. Etching rate was controlled by N2 flow rate. A vertical profile of SiOCH with a high etching rate and less microloading was realized using Ar/C5F10O/N2 plasma chemistry.

Molecular dynamics study of the effect of substrate temperature and Ar ion assisted deposition on the deposition of amorphous TiO{sub 2} films

Energy Technology Data Exchange (ETDEWEB)

Chen, Xian, E-mail: mus_c@qq.com [Science and Technology on Analog Integrated Circuit Laboratory, ChongQing, 401332 (China); Zhang, Jing [Science and Technology on Analog Integrated Circuit Laboratory, ChongQing, 401332 (China); Zhao, Yu-Qing [Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi' an Jiaotong University, Xi’AN, 710049 (China)

2017-05-15

Highlights: • The surface roughness of a-TiO{sub 2} films is decreased with the increment of the Ar ion assisted energy. • The surface roughness of a-TiO{sub 2} films is decreased with higher substrate temperature when the substrate has an island structure. • The assisted Ar ion has power of making a flat surface and increasing the local temperature. • The assisted Ar ion will influence the growth mode with the change of surface atom mobility. • The Volmer-Weber (island) growth mode is inhibited with a high assisted Ar ion energy. - Abstract: This paper has investigated the impact of the substrate temperature and Ar ion assisted deposition on the surface structure formation mechanism and the film properties during the amorphous TiO{sub 2} thin film deposition process with the molecular dynamics simulation method. The results show that the reduction of the surface roughness happen when the energy of Ar ions assisted is increased or the substrate temperature rises, and also the film density on surface is changed with the increasing of Ar ions energy and substrate temperature. It is also found that the Volmer-Weber (island) growth mode of films is promoted by the lower Ar ion energy and higher substrate temperature when the substrate has an island structure. The assisted Ar ion has power of making a flat surface and increasing the local temperature. Besides, it will influence the growth mode with the change of surface atom mobility. With a high assisted Ar ion energy the Volmer-Weber (island) growth mode is inhibited, which will be conducive to the formation of more smooth film surface.

Statistics Report on TEQSA Registered Higher Education Providers

Science.gov (United States)

Australian Government Tertiary Education Quality and Standards Agency, 2015

2015-01-01

This statistics report provides a comprehensive snapshot of national statistics on all parts of the sector for the year 2013, by bringing together data collected directly by TEQSA with data sourced from the main higher education statistics collections managed by the Australian Government Department of Education and Training. The report provides…

AR mutations in 28 patients with androgen insensitivity syndrome (Prader grade 0-3).

Science.gov (United States)

Wang, Yi; Gong, Chunxiu; Wang, Xiou; Qin, Miao

2017-07-01

We investigated the androgen receptor (AR) gene mutation profiles of Chinese patients exhibiting severe androgen insensitivity syndrome (AIS) phenotypes. The present study enrolled 28 patients with genetically diagnosed AIS, who presented with severe phenotypes (Prader grade 0-3). Patients and some family members were screened via amplification and sequencing of their AR exons 1-8, including the corresponding intronic flanking regions. Luteinizing (LH), follicle-stimulating (FSH), and testosterone (T) hormone levels were found to be slightly, but not significantly, higher in patients with complete androgen insensitivity syndrome (CAIS) than in patients with partial androgen insensitivity syndrome (PAIS) (P>0.05). We identified 24 different AR mutations, including 12 that were novel. Ten patients (cases 2, 3, 10, 28, 11, 12, 19, 20, 24, and 25) were found to carry five recurrent mutations (p.Y572S, p.P914S, p.S176R, p.Y782N, and p.R841H); of these, p.Y572S, p.S176R, and p.Y782N were novel. Among the mutations identified in patients with CAIS, six (66.7%) were characterized as single-nucleotide missense mutations, and six (66.7%) were found to be located in the AR ligand-binding domain (LBD). Among the mutations identified in patients with PAIS, 15 (93.8%) were found to be missense, and 11 (68.8%) were found to be located in the LBD. Patients 10 and 28 were determined to harbor the same missense mutation (p.P914S), but were diagnosed with CAIS and PAIS, respectively. Sex hormone levels were slightly, but not significantly, elevated in patients with CAIS compared to those with PAIS. Missense mutations spanning AR exons 1-8 were the predominant form of identified mutations, and these were mostly located in the AR LBD. Approximately 50% of the identified mutations were novel, and have enriched the AR gene-mutation database. Patients harboring identical mutations were in some instances found to exhibit divergent phenotypes.

40Ar/39Ar Dating of Zn-Pb-Ag Mineralization in the Northern Brooks Range, Alaska

Science.gov (United States)

Werdon, Melanie B.; Layer, Paul W.; Newberry, Rainer J.

2004-01-01

The 40Ar/39Ar laser step-heating method potentially can be used to provide absolute ages for a number of formerly undatable, low-temperature ore deposits. This study demonstrates the use of this method by determining absolute ages for Zn-Pb-Ag sediment-hosted massive sulfide deposits and vein-breccia occurrences found throughout a 300-km-long, east-west-trending belt in the northern Brooks Range, Alaska. Massive sulfide deposits are hosted by Mississippian to Pennsylvanian(?) black carbonaceous shale, siliceous mudstone, and lesser chert and carbonate turbidites of the Kuna Formation (e.g., Red Dog, Anarraaq, Lik (Su), and Drenchwater). The vein-breccia occurrences (e.g., Husky, Story Creek, West Kivliktort Mountain, Vidlee, and Kady) are hosted by a deformed but only weakly metamorphosed package of Upper Devonian to Lower Mississippian mixed continental and marine clastic rocks (the Endicott Group) that stratigraphically underlie the Kuna Formation. The vein-breccias are mineralogically similar to, but not spatially associated with, known massive sulfide deposits. The region's largest shale-hosted massive sulfide deposit is Red Dog; it has reserves of 148 Mt grading 16.6 percent zinc, 4.5 percent lead, and 77 g of silver per tonne. Hydrothermally produced white mica in a whole-rock sample from a sulfide-bearing igneous sill within the Red Dog deposit yielded a plateau age of 314.5 Ma. The plateau age of this whole-rock sample records the time at which temperatures cooled below the argon closure temperature of the white mica and is interpreted to represent the minimum age limit for massive sulfide-related hydrothermal activity in the Red Dog deposit. Sulfide-bearing quartz veins at Drenchwater crosscut a hypabyssal intrusion with a maximum biotite age of 337.0 Ma. Despite relatively low sulfide deposition temperatures in the vein-breccia occurrences (162°-251°C), detrital white mica in sandstone immediately adjacent to large vein-breccia zones was partially to

K-Ar and Ar-Ar dating of the Palaeozoic metamorphic complex from the Mid-Bosnian Schist Mts., Central Dinarides, Bosnia and Hercegovina

International Nuclear Information System (INIS)

Pamic, J.; Balogh, K.; Hrvatovic, H.; Balen, D.; Palinkas, L.; Jurkovic, I.

2004-01-01

K-Ar and Ar-Ar whole rock and mineral ages are presented for 25 samples of metamorphic rocks from the Mid-Bosnian Schist Mts., representing one of the largest allochthonous Palaeozoic terranes incorporated within the Internal Dinarides. Four main age groups can be distinguished: 1) Variscan (∼ 343 Ma), 2) post-Variscan (288-238 Ma), 3) Early Cretaceous (mainly 121-92 Ma), and 4) Eocene (59--35 Ma) ages. Apart from this, an Oligocene (31 Ma) age was obtained on Alpine vein hyalophane. The radiometric dating indicates a polyphase metamorphic evolution of the Palaeozoic formations and suggests a pre-Carboniferous age of the volcano-sedimentary protoliths, an Early Carboniferous age of Variscan metamorphism and deformation, post-Variscan volcanism, an Early Cretaceous metamorphic overprint related to out-of-sequence thrusting of the Palaeozoic complex, and an Eocene and Oligocene metamorphic overprint related to the main Alpine compressional deformation and subsequent strike-slip faulting, and uplift of the metamorphic core. Accordingly, the Mid-Bosnian Schist Mts. can be correlated in its multistage geodynamic evolution with some Palaeozoic tectonostratigraphic units from the Austroalpine domain in the Eastern Alps. (author)

Importance of rotational adiabaticity in collisions of CO2 super rotors with Ar and He

Science.gov (United States)

Murray, Matthew J.; Ogden, Hannah M.; Mullin, Amy S.

2018-02-01

The collision dynamics of optically centrifuged CO2 with Ar and He are reported here. The optical centrifuge produces an ensemble of CO2 molecules in high rotational states (with J ˜ 220) with oriented angular momentum. Polarization-dependent high-resolution transient IR absorption spectroscopy was used to measure the relaxation dynamics in the presence of Ar or He by probing the CO2 J = 76 and 100 states with Er o t=2306 and 3979 cm-1, respectively. The data show that He relaxes the CO2 super rotors more quickly than Ar. Doppler-broadened line profiles show that He collisions induce substantially larger rotation-to-translation energy transfer. CO2 super rotors have greater orientational anisotropy with He collisions and the anisotropy from the He collisions persists longer than with Ar. Super rotor relaxation dynamics are discussed in terms of mass effects related to classical gyroscope physics and collisional rotational adiabaticity.

I-Xe and 40Ar-39Ar dating of silicate from Weekeroo Station and Netschaevo IIE iron meteorites

International Nuclear Information System (INIS)

Niemeyer, S.

1980-01-01

Silicate inclusions from two IIE iron meteorites were dated by the I-Xe and 40 Ar- 39 Ar techniques. Weekeroo Station, a 'normal' IIE iron, shows no loss of radiogenic 40 Ar at low temperature, and the well defined 40 Ar- 39 Ar plateau yields an age of 4.54 +- 0.03 Byr. The xenon data define a good I-Xe correlation with an age of + 10.9 +- 0.5 Myr relative to Bjurbole. Despite its relatively young age, Weekeroo Station's ( 129 Xe/ 132 Xe)sub(trapped) ratio (= 0.84 +- 0.05) lies significantly below the solar value. Netschaevo silicate has a chondritic composition, unlike 'normal' IIE silicate which is more differentiated. Nevertheless Netschaevo gives a 40 Ar- 39 Ar plateau-age of only 3.79 +- 0.03 Byr, with the xenon data failing to define an I-Xe isochron. Only irons from the IAB and IIE groups contain silicate inclusions, but these two groups differ in many other respects, mostly suggesting that IAB meteorites are more primitive. The I-Xe chronology supports this suggestion inasmuch as Weekeroo Station formed well after IAB silicates. The four silicate-bearing IIE irons which have now been dated can be subdivided into distinct pairs: Weekeroo Station and Colomera formed near the beginning of the solar system, while Netschaevo and Kodaikanal both formed only 3.8 Byr ago. A review of other properties of these meteorites generally supports this subdivision. This work underscores the complexity of the history of IIE meteorites; in particular, an adequate model must account for the formation of two IIE irons at 3.8 Byr without disturbing rare gases in Weekeroo Station. All formation models are quite speculative, but the one which seems best to fit the available evidence postulates two parent bodies: the 3.8 Byr old silicate formed on one parent body, all other IIE material resided in a separate body, and subsequent collision(s) mixed the young silicate with IIE metal. (author)

40Ar/ 39Ar, K-Ar and 230Th- 238U dating of the Laschamp excursion: A radioisotopic tie-point for ice core and climate chronologies

Science.gov (United States)

Singer, Brad S.; Guillou, Hervé; Jicha, Brian R.; Laj, Carlo; Kissel, Catherine; Beard, Brian L.; Johnson, Clark M.

2009-08-01

A brief period of enhanced 10Be flux that straddles the interstadial warm period known as Dansgaard-Oeschger event 10 in Greenland and its counterpart in Antarctica, the Antarctic Isotope Maximum 10 is but one consequence of the weakening of Earth's magnetic field associated with the Laschamp excursion. This 10Be peak measured in the GRIP ice core is dated at 41,250 y b2k (= before year 2000 AD) in the most recent GICC05 age model obtained from the NorthGRIP core via multi-parameter counting of annual layers. Uncertainty in the age of the 10Be peak is, however, no better than ± 1630 y at the 95% confidence level, reflecting accumulated error in identifying annual layers. The age of the Laschamp excursion [Guillou, H., Singer, B.S., Laj, C., Kissel, C., Scaillet, S., Jicha, B., 2004. On the age of the Laschamp geomagnetic excursion. Earth Planet. Sci. Lett. 227, 331-343.] is revised on the basis of new 40Ar/ 39Ar, unspiked K-Ar and 238U- 230Th data from three lava flows in the Massif Central, France, together with the 40Ar/ 39Ar age of a transitionally magnetized lava flow at Auckland, New Zealand. Combined, these data yield an age of 40,700 ± 950 y b2k, where the uncertainty includes both analytical and systematic ( 40K and 230Th decay constant) errors. Taking the radioisotopic age as a calibration tie point suggests that the layer-counting chronologies for the NorthGRIP and GISP2 ice cores are more accurate and precise than previously thought at depths corresponding to the Laschamp excursion.

K-Ar ages for the Yahazudake volcanic rocks from southwest Kyushu, Japan; Kyushu nanseibu yahazudake kazanganrui no K-Ar nendai

Energy Technology Data Exchange (ETDEWEB)

Yokose, H.; Kikuchi, W. [Kumamoto Univ. (Japan)] Nagao, K. [Okayama Univ. (Japan)264000] Kodama, K. [Kochi Univ. (Japan)

1998-05-05

Many volcanic rocks, seemed to be erupted during the period from the Pliocene epoch to the Pleistocene epoch, are distributed abounding in Kyushu, Japan. In this study, K-Ar ages determination about the 4 samples which represents the Hisatsu volcanic rocks distributed around Yahazudake and rhyolite distributed in Gesujima placed in the southernmost extremity of Amakusa Shimojima, was conducted. And consideration of time/space distribution of the Hisatsu volcanic rocks upon collecting the data which were reported until now and the data obtained by the present K-Ar age determination, was done. In the result of the present measurement, the absolute age of the Hisatsu volcanic rocks distributed around Minamata-shi became clear. I was clarified that Yahazudake volcanic rocks consisted of andesite, which is comparatively lacking in potassium, were formed during about 100 thousand years from 1.98 to 2.08 Ma, and Ontake volcanic rocks which exists for the bottom erupted at about 2.15 Ma. And, the age value of 2.89 Ma was obtained from Ushibuka rhyolite distributed in Gesujima. 35 refs., 4 figs., 3 tabs.

Measurements of the 40Ar(n, γ)41Ar radiative-capture cross section between 0.4 and 14.8 MeV

Science.gov (United States)

Bhike, Megha; Fallin, B.; Tornow, W.

2014-09-01

The 40Ar(n, γ)41Ar neutron capture cross section has been measured between 0.4 and 14.8 MeV neutron energy using the activation technique. The data are important for estimating backgrounds in argon-based neutrino and dark-matter detectors and in the neutrino-less double-beta decay search GERDA, which uses liquid argon as cooling and shielding medium. For the first time the 40Ar(n, γ)41Ar cross section has been measured for neutron energies above 1 MeV. Our results are compared to the evaluation ENDF/B-VII.1 and the calculated prediction TENDL-2013. The latter agrees very well with the present results.

Spatial autocorrelation method using AR model; Kukan jiko sokanho eno AR model no tekiyo

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, H; Obuchi, T; Saito, T [Iwate University, Iwate (Japan). Faculty of Engineering

1996-05-01

Examination was made about the applicability of the AR model to the spatial autocorrelation (SAC) method, which analyzes the surface wave phase velocity in a microtremor, for the estimation of the underground structure. In this examination, microtremor data recorded in Morioka City, Iwate Prefecture, was used. In the SAC method, a spatial autocorrelation function with the frequency as a variable is determined from microtremor data observed by circular arrays. Then, the Bessel function is adapted to the spatial autocorrelation coefficient with the distance between seismographs as a variable for the determination of the phase velocity. The result of the AR model application in this study and the results of the conventional BPF and FFT method were compared. It was then found that the phase velocities obtained by the BPF and FFT methods were more dispersed than the same obtained by the AR model. The dispersion in the BPF method is attributed to the bandwidth used in the band-pass filter and, in the FFT method, to the impact of the bandwidth on the smoothing of the cross spectrum. 2 refs., 7 figs.

Androgen receptor and its splice variant, AR-V7, differentially regulate FOXA1 sensitive genes in LNCaP prostate cancer cells.

Science.gov (United States)

Krause, William C; Shafi, Ayesha A; Nakka, Manjula; Weigel, Nancy L

2014-09-01

Prostate cancer (PCa) is an androgen-dependent disease, and tumors that are resistant to androgen ablation therapy often remain androgen receptor (AR) dependent. Among the contributors to castration-resistant PCa are AR splice variants that lack the ligand-binding domain (LBD). Instead, they have small amounts of unique sequence derived from cryptic exons or from out of frame translation. The AR-V7 (or AR3) variant is constitutively active and is expressed under conditions consistent with CRPC. AR-V7 is reported to regulate a transcriptional program that is similar but not identical to that of AR. However, it is unknown whether these differences are due to the unique sequence in AR-V7, or simply to loss of the LBD. To examine transcriptional regulation by AR-V7, we have used lentiviruses encoding AR-V7 (amino acids 1-627 of AR with the 16 amino acids unique to the variant) to prepare a derivative of the androgen-dependent LNCaP cells with inducible expression of AR-V7. An additional cell line was generated with regulated expression of AR-NTD (amino acids 1-660 of AR); this mutant lacks the LBD but does not have the AR-V7 specific sequence. We find that AR and AR-V7 have distinct activities on target genes that are co-regulated by FOXA1. Transcripts regulated by AR-V7 were similarly regulated by AR-NTD, indicating that loss of the LBD is sufficient for the observed differences. Differential regulation of target genes correlates with preferential recruitment of AR or AR-V7 to specific cis-regulatory DNA sequences providing an explanation for some of the observed differences in target gene regulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tumour-specific HMG-CoAR is an independent predictor of recurrence free survival in epithelial ovarian cancer.

LENUS (Irish Health Repository)

Brennan, Donal J

2010-01-01

BACKGROUND: Our group previously reported that tumour-specific expression of the rate-limiting enzyme in the mevalonate pathway, 3-hydroxy-3-methylglutharyl-coenzyme A reductase (HMG-CoAR) is associated with more favourable tumour parameters and a good prognosis in breast cancer. In the present study, the prognostic value of HMG-CoAR expression was examined in tumours from a cohort of patients with primary epithelial ovarian cancer. METHODS: HMG-CoAR expression was assessed using immunohistochemistry (IHC) on tissue microarrays (TMA) consisting of 76 ovarian cancer cases, analysed using automated algorithms to develop a quantitative scoring model. Kaplan Meier analysis and Cox proportional hazards modelling were used to estimate the risk of recurrence free survival (RFS). RESULTS: Seventy-two tumours were suitable for analysis. Cytoplasmic HMG-CoAR expression was present in 65% (n = 46) of tumours. No relationship was seen between HMG-CoAR and age, histological subtype, grade, disease stage, estrogen receptor or Ki-67 status. Patients with tumours expressing HMG-CoAR had a significantly prolonged RFS (p = 0.012). Multivariate Cox regression analysis revealed that HMG-CoAR expression was an independent predictor of improved RFS (RR = 0.49, 95% CI (0.25-0.93); p = 0.03) when adjusted for established prognostic factors such as residual disease, tumour stage and grade. CONCLUSION: HMG-CoAR expression is an independent predictor of prolonged RFS in primary ovarian cancer. As HMG-CoAR inhibitors, also known as statins, have demonstrated anti-neoplastic effects in vitro, further studies are required to evaluate HMG-CoAR expression as a surrogate marker of response to statin treatment, especially in conjunction with current chemotherapeutic regimens.

Tumour-specific HMG-CoAR is an independent predictor of recurrence free survival in epithelial ovarian cancer

LENUS (Irish Health Repository)

Brennan, Donal J

2010-04-01

Abstract Background Our group previously reported that tumour-specific expression of the rate-limiting enzyme in the mevalonate pathway, 3-hydroxy-3-methylglutharyl-coenzyme A reductase (HMG-CoAR) is associated with more favourable tumour parameters and a good prognosis in breast cancer. In the present study, the prognostic value of HMG-CoAR expression was examined in tumours from a cohort of patients with primary epithelial ovarian cancer. Methods HMG-CoAR expression was assessed using immunohistochemistry (IHC) on tissue microarrays (TMA) consisting of 76 ovarian cancer cases, analysed using automated algorithms to develop a quantitative scoring model. Kaplan Meier analysis and Cox proportional hazards modelling were used to estimate the risk of recurrence free survival (RFS). Results Seventy-two tumours were suitable for analysis. Cytoplasmic HMG-CoAR expression was present in 65% (n = 46) of tumours. No relationship was seen between HMG-CoAR and age, histological subtype, grade, disease stage, estrogen receptor or Ki-67 status. Patients with tumours expressing HMG-CoAR had a significantly prolonged RFS (p = 0.012). Multivariate Cox regression analysis revealed that HMG-CoAR expression was an independent predictor of improved RFS (RR = 0.49, 95% CI (0.25-0.93); p = 0.03) when adjusted for established prognostic factors such as residual disease, tumour stage and grade. Conclusion HMG-CoAR expression is an independent predictor of prolonged RFS in primary ovarian cancer. As HMG-CoAR inhibitors, also known as statins, have demonstrated anti-neoplastic effects in vitro, further studies are required to evaluate HMG-CoAR expression as a surrogate marker of response to statin treatment, especially in conjunction with current chemotherapeutic regimens.

Tumour-specific HMG-CoAR is an independent predictor of recurrence free survival in epithelial ovarian cancer

International Nuclear Information System (INIS)

Brennan, Donal J; Jirstrom, Karin; Brändstedt, Jenny; Rexhepaj, Elton; Foley, Michael; Pontén, Fredrik; Uhlén, Mathias; Gallagher, William M; O'Connor, Darran P; O'Herlihy, Colm

2010-01-01

Our group previously reported that tumour-specific expression of the rate-limiting enzyme in the mevalonate pathway, 3-hydroxy-3-methylglutharyl-coenzyme A reductase (HMG-CoAR) is associated with more favourable tumour parameters and a good prognosis in breast cancer. In the present study, the prognostic value of HMG-CoAR expression was examined in tumours from a cohort of patients with primary epithelial ovarian cancer. HMG-CoAR expression was assessed using immunohistochemistry (IHC) on tissue microarrays (TMA) consisting of 76 ovarian cancer cases, analysed using automated algorithms to develop a quantitative scoring model. Kaplan Meier analysis and Cox proportional hazards modelling were used to estimate the risk of recurrence free survival (RFS). Seventy-two tumours were suitable for analysis. Cytoplasmic HMG-CoAR expression was present in 65% (n = 46) of tumours. No relationship was seen between HMG-CoAR and age, histological subtype, grade, disease stage, estrogen receptor or Ki-67 status. Patients with tumours expressing HMG-CoAR had a significantly prolonged RFS (p = 0.012). Multivariate Cox regression analysis revealed that HMG-CoAR expression was an independent predictor of improved RFS (RR = 0.49, 95% CI (0.25-0.93); p = 0.03) when adjusted for established prognostic factors such as residual disease, tumour stage and grade. HMG-CoAR expression is an independent predictor of prolonged RFS in primary ovarian cancer. As HMG-CoAR inhibitors, also known as statins, have demonstrated anti-neoplastic effects in vitro, further studies are required to evaluate HMG-CoAR expression as a surrogate marker of response to statin treatment, especially in conjunction with current chemotherapeutic regimens

75 FR 12163 - Class E Airspace; Mountain View, AR

Science.gov (United States)

2010-03-15

...-1181; Airspace Docket No. 09-ASW-36] Class E Airspace; Mountain View, AR AGENCY: Federal Aviation... Class E airspace at Mountain View, AR. Decommissioning of the Wilcox non-directional beacon (NDB) at... View, AR. Airspace reconfiguration is necessary due to the decommissioning of the Wilcox NDB and the...

Bone blood flow measured by 41Ar clearance formed by 44Ca(n,α)41Ar

International Nuclear Information System (INIS)

Rosenthal, M.S.; DeLuca, P.M. Jr.; Pearson, D.W.; Nickles, R.J.

1983-01-01

A technique to measure regional inert gas washout in bone, in vivo, by measuring 41 Ar clearance formed by fast-neutron activation of 44 Ca has been developed. Following fast-neutron irradiation of whole rats, the perfusion-limited clearance of 41 Ar was measured for both dead and living rats. The clearance rate for the live rats indicate that the bone perfusion is in the range of 3 to 20 ml/100 Argon distribution volume

Acoustic resonance spectroscopy (ARS): ARS300 operations manual, software version 2.01

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-07-25

Acoustic Resonance Spectroscopy (ARS) is a nondestructive evaluation technology developed at the Los Alamos National Laboratory. The ARS technique is a fast, safe, and nonintrusive technique that is particularly useful when a large number of objects need to be tested. Any physical object, whether solid, hollow, or fluid filled, has many modes of vibration. These modes of vibration, commonly referred to as the natural resonant modes or resonant frequencies, are determined by the object`s shape, size, and physical properties, such as elastic moduli, speed of sound, and density. If the object is mechanically excited at frequencies corresponding to its characteristic natural vibrational modes, a resonance effect can be observed when small excitation energies produce large amplitude vibrations in the object. At other excitation frequencies, i.e., vibrational response of the object is minimal.

K-Ar ages of the Auckland geomagnetic excursions

International Nuclear Information System (INIS)

Mochizuki, Nobutatsu; Tsunakawa, Hideo; Shibuya, Hidetoshi; Tagami, Takahiro; Ozawa, Ayako; Cassidy, John; Smith, E.M.

2004-01-01

K-Ar age determinations were made on two monogenetic volcanoes in the Auckland volcanic field, New Zealand, which have recorded the Auckland geomagnetic excursions. For the Wiri volcano with the north-down intermediate paleomagnetic direction, five samples gave a weighted mean age of 27±5 (1σ) ka. For the Hampton Park volcano with the west-up intermediate direction, three samples gave a weighted mean of 55±5(1σ) ka. Since these two K-Ar ages are distinguished at 2σ level, it is inferred that at least two geomagnetic excursions can be recognized in Auckland. The age of the Hampton Park is barely distinguished from the established age range of the Laschamp excursion (39-45 ka) at 2σ level. The age of the Wiri coincides with the age of c. 30 ka in which excursions have been found from sedimentary and volcanic records. The reported excursions from volcanic rocks show a VGP cluster in the central to northern Pacific region which is distinct from the VGP paths or clusters during polarity reversals. (author)

A microdose study of ¹⁴C-AR-709 in healthy men: pharmacokinetics, absolute bioavailability and concentrations in key compartments of the lung.

Science.gov (United States)

Lappin, G; Boyce, M J; Matzow, T; Lociuro, S; Seymour, M; Warrington, S J

2013-09-01

To explore, in a microdose (phase-0) study, the pharmacokinetics, bioavailability and concentrations in key compartments of the lung, of AR-709, a novel diaminopyrimidine antibiotic for the treatment of respiratory infection. Four healthy men each received two single, 100 μg microdoses of ¹⁴C-AR-709, 7 days apart: the first was administered intravenously (IV), the second orally. Plasma pharmacokinetics of ¹⁴C and unchanged AR-709 were obtained by high-performance liquid chromatography and accelerator mass spectrometry (AMS). Next, 15 healthy men received a single, 100 μg microdose of ¹⁴C-AR-709 IV. Plasma, bronchoalveolar lavage fluid, alveolar macrophages and bronchial mucosal biopsy samples were analysed by AMS. After IV administration, clearance of AR-709 was 496 mL/min, volume of distribution was 1,700 L and the absolute oral bioavailability was 2.5 %. Excretion in urine was negligible. At 8-12 h after IV dosing, ¹⁴C concentrations in lung samples were 15- (bronchial mucosa) to 200- (alveolar macrophages) fold higher than in plasma. In alveolar macrophages, ¹⁴C was still mostly associated with AR-709 at 12 h after dosing. The results of this microdose study indicate that AR-709 attains concentrations appreciably higher within the lung than in plasma. Its low oral bioavailability however, precludes oral administration. Although IV administration would appear to be an effective route of administration, this would limit the use of AR-709 to a clinical setting and would therefore be economically unsustainable. If further clinical development were to be undertaken, therefore, an alternative route of administration would be necessary.

The 40Ar/39Ar dating of core recovered by the Hawaii Scientific Drilling Project (phase 2), Hilo, Hawaii

Science.gov (United States)

Sharp, Warren D.; Renne, Paul R.

2005-04-01

The Hawaii Scientific Drilling Project, phase 2 (HSDP-2), recovered core from a ˜3.1-km-thick section through the eastern flanks of Mauna Loa and Mauna Kea volcanoes. We report results of 40Ar/39Ar incremental heating by broad-beam infrared laser of 16 basaltic groundmass samples and 1 plagioclase separate, mostly from K-poor tholeiites. The tholeiites generally have mean radiogenic 40Ar enrichments of 1-3%, and some contain excess 40Ar; however, isochron ages of glass-poor samples preserve stratigraphic order in all cases. A 246-m-thick sequence of Mauna Loa tholeiitic lavas yields an isochron age of 122 ± 86 kyr (all errors 2σ) at its base. Beneath the Mauna Loa overlap sequence lie Mauna Kea's postshield and shield sequences. A postshield alkalic lava yields an age of 236 ± 16 kyr, in agreement with an age of 240 ± 14 kyr for a geochemically correlative flow in the nearby HSDP-1 core hole, where more complete dating of the postshield sequence shows it to have accumulated at 0.9 ± 0.4 m/kyr, from about 330 to <200 ka. Mauna Kea's shield consists of subaerial tholeiitic flows to a depth of 1079 m below sea level, then shallow submarine flows, hyaloclastites, pillow lavas, and minor intrusions to core bottom at 3098 m. Most subaerial tholeiitic flows fail to form isochrons; however, a sample at 984 m yields an age of 370 ± 180 kyr, consistent with ages from similar levels in HSDP-1. Submarine tholeiites including shallow marine vitrophyres, clasts from hyaloclastites, and pillow lavas were analyzed; however, only pillow lava cores from 2243, 2614, and 2789 m yield reliable ages of 482 ± 67, 560 ± 150, and 683 ± 82 kyr, respectively. A linear fit to ages for shield samples defines a mean accumulation rate of 8.6 ± 3.1 m/kyr and extrapolates to ˜635 kyr at core bottom. Alternatively, a model relating Mauna Kea's growth to transport across the Hawaiian hot spot that predicts downward accelerating accumulation rates that reach ˜20 m/kyr at core bottom (De

40Ar/39Ar geochronology and volume estimates of the Tasmantid Seamounts: Support for a change in the motion of the Australian plate

Science.gov (United States)

Crossingham, Tracey J.; Vasconcelos, Paulo M.; Cunningham, Toby; Knesel, Kurt M.

2017-09-01

New volume estimates and 40Ar/39Ar ages for the Tasmantid Seamounts are reported to investigate the origin of volcanism and potential links between volcanism and changes in the speed and direction of migration of the Australian plate during the Cenozoic. The results show that the average extrusive volume of individual volcanoes along the seamount chain is 2587 ± 3078 km3 (1 s), and that volumes generally increase towards the south. An exception, the Britannia Guyot, located in the middle of the seamount chain, is the most voluminous (11,374 km3). Nineteen new 40Ar/39Ar ages, from Wreck to Gascoyne, show that the emplacement of the Tasmantid Seamounts occurred between 33.2 ± 1.5 and 6.5 ± 0.6 Ma. A single linear regression applied to the age versus latitude data, assuming volcanism to be caused by plate migration over a stationary hotspot, reveals a plate migration rate of 62 ± 2 kmMa- 1 (R2 = 0.97; n = 27) between 33 and 6 Ma. However, the bend in the seamount track, corresponding with the period of largest eruptive volumes, suggests three distinct segments in the Tasmantid age versus latitude data. The northern segment is consistent with a plate migration rate of 75 ± 10 kmMa- 1 (R2 = 0.88; n = 10) and the southern segment reveals a plate migration rate of 64 ± 4 kmMa- 1 (R2 = 0.94; n = 17). The period between these two segments, from 25 to 19 Ma, overlaps with the period of slow migration and change in the direction of the Australian plate derived from the age versus latitude distribution of continental central volcanoes. The new Tasmantid Seamount results support the interpretation that there were changes in the velocity and direction to Australia's northward trajectory, possibly resulting from a series of collisional events.

Synthesis of Au nanoparticles at the surface and embedded in carbonaceous matrix by 150 keV Ar ion irradiation

International Nuclear Information System (INIS)

Prakash, Jai; Tripathi, Jalaj; Tripathi, A; Kumar, P; Asokan, K; Avasthi, D K; Rigato, V; Pivin, J C; Chae, Keun Hwa; Gautam, Sanjeev

2011-01-01

We report on synthesis of spherical Au nanoparticles at the surface and embedded in carbonaceous matrix by 150 keV Ar ion irradiation of thin Au film on polyethyleneterepthlate (PET). The pristine and irradiated samples are characterized by Rutherford backscattering spectrometry (RBS), atomic force microscopy, scanning electron microscopy and transmission electron microscopy (TEM) techniques. RBS spectra reveal the sputtering of Au film and interface mixing, increasing with increasing fluence. Surface morphology shows that at the fluence of 5 x 10 15 ions cm -2 , dewetting of thin Au film begins and partially connected nanostructures are formed whereas, at the higher fluence of 5 x 10 16 ions cm -2 , isolated spherical Au nanoparticles (45 ± 20 nm) are formed at the surface. Cross-sectional TEM observations also evidence the Au nanoparticles at the surface and mixed metal-polymer region indicating the formation of nanocomposites with small Au nanoparticles. The results are explained by the crater formation, sputtering followed by dewetting of the thin Au film and interdiffusion at the interface, through molten zones due to thermal spike induced by Ar ions.

Etching properties of BLT films in CF4/Ar plasma

International Nuclear Information System (INIS)

Kim, Dong Pyo; Kim, Kyoung Tae; Kim, Chang Il

2003-01-01

CF 4 /Ar plasma mass content and etching rate behavior of BLT thin films were investigated in inductively coupled plasma (ICP) reactor as functions of CF 4 /Ar gas mixing ratio, rf power, and dc bias voltage. The variation of relative volume densities for F and Ar atoms were measured by the optical emission spectroscopy (OES). The etching rate as functions of Ar content showed the maximum of 803 A/min at 80 % Ar addition into CF 4 plasma. The presence of maximum etch rate may be explained by the concurrence of two etching mechanisms such as physical sputtering and chemical reaction. The role of Ar ion bombardment includes destruction of metal (Bi, La, Ti)-O bonds as well as support of chemical reaction of metals with fluorine atoms

Enhancement of sp3 hybridized C in amorphous carbon films by Ar ion bombardment and Si incorporation

International Nuclear Information System (INIS)

Jung, Hae-Suk; Park, Hyung-Ho; Mendieta, I.R.; Smith, D.A.

2003-01-01

We report an effective method of increasing the sp 3 hybridization fraction in sputtered amorphous carbon (a-C) film by the combination of Ar ion bombardment and Si incorporation. In the deposition of an a-C film, Ar ion bombardment by controlling the applied bias voltage plays a role in creating high stress in film and causes the local bonding configuration to change to a sp 3 hybridized bond. Simultaneously, the incorporated Si in an a-C network breaks the sp 2 hybridized bonded ring and promotes the formation of a sp 3 hybridized bond. This enhancement of the sp 3 hybridized bonding characteristic is maximized for an a-C film with 23 at. % of Si and 100-150 V of applied bias voltage. In this region, the increase of resistivity, optical band gap, and mechanical hardness of a-C is attributed to the reduction of the sp 2 hybridized bonded ring and increased fraction of the sp 3 hybridized bond. However, at a higher bias voltage above 150 V, the enhancement effect is reduced due to the resputtering and thermally activated reconversion of a sp 3 to a sp 2 hybridized bond

Plastid and mitochondrion genomic sequences from Arctic Chlorella sp. ArM0029B

Science.gov (United States)

2014-01-01

Background Chorella is the representative taxon of Chlorellales in Trebouxiophyceae, and its chloroplast (cp) genomic information has been thought to depend only on studies concerning Chlorella vulgaris and GenBank information of C. variablis. Mitochondrial (mt) genomic information regarding Chlorella is currently unavailable. To elucidate the evolution of organelle genomes and genetic information of Chlorella, we have sequenced and characterized the cp and mt genomes of Arctic Chlorella sp. ArM0029B. Results The 119,989-bp cp genome lacking inverted repeats and 65,049-bp mt genome were sequenced. The ArM0029B cp genome contains 114 conserved genes, including 32 tRNA genes, 3 rRNA genes, and 79 genes encoding proteins. Chlorella cp genomes are highly rearranged except for a Chlorella-specific six-gene cluster, and the ArM0029B plastid resembles that of Chlorella variabilis except for a 15-kb gene cluster inversion. In the mt genome, 62 conserved genes, including 27 tRNA genes, 3 rRNA genes, and 32 genes encoding proteins were determined. The mt genome of ArM0029B is similar to that of the non-photosynthetic species Prototheca and Heicosporidium. The ArM0029B mt genome contains a group I intron, with an ORF containing two LAGLIDADG motifs, in cox1. The intronic ORF is shared by C. vulgaris and Prototheca. The phylogeny of the plastid genome reveals that ArM0029B showed a close relationship of Chlorella to Parachlorella and Oocystis within Chlorellales. The distribution of the cox1 intron at 721 support membership in the order Chlorellales. Mitochondrial phylogenomic analyses, however, indicated that ArM0029B shows a greater affinity to MX-AZ01 and Coccomyxa than to the Helicosporidium-Prototheca clade, although the detailed phylogenetic relationships among the three taxa remain to be resolved. Conclusions The plastid genome of ArM0029B is similar to that of C. variabilis. The mt sequence of ArM0029B is the first genome to be reported for Chlorella. Chloroplast

VLA radio observations of AR Scorpii

Science.gov (United States)

Stanway, E. R.; Marsh, T. R.; Chote, P.; Gänsicke, B. T.; Steeghs, D.; Wheatley, P. J.

2018-03-01

Aims: AR Scorpii is unique amongst known white dwarf binaries in showing powerful pulsations extending to radio frequencies. Here we aim to investigate the multi-frequency radio emission of AR Sco in detail, in order to constrain its origin and emission mechanisms. Methods: We present interferometric radio frequency imaging of AR Sco at 1.5, 5 and 9 GHz, analysing the total flux and polarization behaviour of this source at high time resolution (10, 3 and 3 s), across a full 3.6 h orbital period in each band. Results: We find strong modulation of the radio flux on the orbital period and the orbital sideband of the white dwarf's spin period (also known as the "beat" period). This indicates that, like the optical flux, the radio flux arises predominantly from on or near the inner surface of the M-dwarf companion star. The beat-phase pulsations of AR Sco decrease in strength with decreasing frequency. They are strongest at 9 GHz and at an orbital phase 0.5. Unlike the optical emission from this source, radio emission from AR Sco shows weak linear polarization but very strong circular polarization, reaching 30% at an orbital phase 0.8. We infer the probable existence of a non-relativistic cyclotron emission component, which dominates at low radio frequencies. Given the required magnetic fields, this also likely arises from on or near the M-dwarf. A table of the flux time series is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A66

40Ar/39Ar dating of the Late Cretaceous

International Nuclear Information System (INIS)

Gaylor, Jonathan

2013-01-01

As part of the wider European GTS Next project, I propose new constraints on the ages of the Late Cretaceous, derived from a multitude of geochronological techniques, and successful stratigraphic interpretations from Canada and Japan. In the Western Canada Sedimentary Basin, we propose a new constraint on the age of the K/Pg boundary in the Red Deer River section (Alberta, Canada). We were able to cyclo-stratigraphically tune sediments in a non-marine, fluvial environment utilising high-resolution proxy records suggesting a 11-12 precession related cyclicity. Assuming the 40 Ar/ 39 Ar method is inter-calibrated with the cyclo-stratigraphy, the apparent age for C29r suggests that the K/Pg boundary falls between eccentricity maxima and minima, yielding an age of the C29r between 65.89 ± 0.08 and 66.30 ± 0.08 Ma. Assuming that the bundle containing the coal horizon represents a precession cycle, the K/Pg boundary is within the analytical uncertainty of the youngest zircon population achieving a revised age for the K/Pg boundary as 65.75 ± 0.06 Ma. The Campanian - Maastrichtian boundary is preserved in the sedimentary succession of the Horseshoe Canyon Formation and has been placed 8 m below Coal nr. 10. Cyclo-stratigraphic studies show that the formation of these depositional sequences (alternations) of all scales are influenced directly by sea-level changes due to precession but more dominated by eccentricity cycles proved in the cyclo-stratigraphic framework and is mainly controlled by sand horizons, which have been related by auto-cyclicity in a dynamic sedimentary setting. Our work shows that the Campanian - Maastrichtian boundary in the Western Canada Sedimentary Basin coincides with 2.5 eccentricity cycles above the youngest zircon age population at the bottom of the section and 4.9 Myr before the Cretaceous - Palaeogene boundary (K/Pg), and thus corresponds to an absolute age of 70.65 ± 0.09 Ma producing an 1.4 Myr younger age than recent published ages

HIGH-RESOLUTION FOURIER TRANSFORM SPECTROSCOPY OF LANTHANUM IN Ar DISCHARGE IN THE NEAR-INFRARED

Energy Technology Data Exchange (ETDEWEB)

Güzelçimen, F.; Başar, Gö. [Faculty of Science, Physics Department, Istanbul University, Tr-34134 Vezneciler, Istanbul (Turkey); Tamanis, M.; Kruzins, A.; Ferber, R. [Laser Centre, The University of Latvia, Rainis Boulevard 19, LV-1586 Riga (Latvia); Windholz, L. [Institut für Experimentalphysik, Technische Universität Graz, A-8010 Graz, Petersgasse 16 (Austria); Kröger, S., E-mail: gbasar@istanbul.edu.tr, E-mail: sophie.kroeger@htw-berlin.de [Hochschule für Technik und Wirtschaft Berlin, Wilhelminenhofstr. 75A, D-12459 Berlin (Germany)

2013-10-01

A high-resolution spectrum of lanthanum has been recorded by a Fourier Transform spectrometer in the wavelength range from 833 nm to 1666 nm (6000 cm{sup –1} to 12,000 cm{sup –1}) using as light source a hollow cathode lamp operated with argon as the discharge carrier gas. In total, 2386 spectral lines were detected in this region, of which 555 lines could be classified as La I transitions and 10 lines as La II transitions. All La II transitions and 534 of these La I transitions were classified for the first time, and 6 of the La II transitions and 433 of the classified La I transitions appear to be new lines, which could not be found in the literature. The corresponding energy level data of classified lines are given. Additionally, 430 lines are assigned as Ar I lines and 394 as Ar II lines, of which 179 and 77, respectively, were classified for the first time. All 77 classified Ar II transitions as well as 159 of the classified Ar I transitions are new lines. Furthermore, the wavenumbers of 997 unclassified spectral lines were determined, 235 of which could be assigned as La lines, because of their hyperfine pattern. The remaining 762 lines may be either unclassified Ar lines or unresolved and unclassified La lines with only one symmetrical peak with an FWHM in the same order of magnitude as the Ar lines. The accuracy of the wavenumber for the classified lines with signal-to-noise-ratio higher than four is better than 0.006 cm{sup –1} which corresponds to an accuracy of 0.0004 nm at 830 nm and 0.0017 nm at 1660 nm, respectively.

Argon in hornblende, biotite and muscovite in geologic cooling - Ar-40/Ar-39-investigations

International Nuclear Information System (INIS)

Rittman, K.L.

1984-01-01

The results of the Ar-40/Ar-39 studies are discussed under the aspect of whether the age data of the minerals indicate a cooling process. The author hopes that isotope dating of minerals with different closing temperatures will describe the temperature/time history of an area in the temperature range of 600 to 200 0 C. The findings are analyzed under three aspects: How much do they contribute to the initial methodological question, what do they contribute to the regional geology of the areas investigated, and in what respects do they extent the present knowledge of the geochronological analysis, i.e. its techniques and interpretation. (orig.) [de

AR Expression in Breast Cancer CTCs Associates with Bone Metastases.

Science.gov (United States)

Aceto, Nicola; Bardia, Aditya; Wittner, Ben S; Donaldson, Maria C; O'Keefe, Ryan; Engstrom, Amanda; Bersani, Francesca; Zheng, Yu; Comaills, Valentine; Niederhoffer, Kira; Zhu, Huili; Mackenzie, Olivia; Shioda, Toshi; Sgroi, Dennis; Kapur, Ravi; Ting, David T; Moy, Beverly; Ramaswamy, Sridhar; Toner, Mehmet; Haber, Daniel A; Maheswaran, Shyamala

2018-04-01

Molecular drivers underlying bone metastases in human cancer are not well understood, in part due to constraints in bone tissue sampling. Here, RNA sequencing was performed of circulating tumor cells (CTC) isolated from blood samples of women with metastatic estrogen receptor (ER) + breast cancer, comparing cases with progression in bone versus visceral organs. Among the activated cellular pathways in CTCs from bone-predominant breast cancer is androgen receptor (AR) signaling. AR gene expression is evident, as is its constitutively active splice variant AR-v7. AR expression within CTCs is correlated with the duration of treatment with aromatase inhibitors, suggesting that it contributes to acquired resistance to endocrine therapy. In an established breast cancer xenograft model, a bone-tropic derivative displays increased AR expression, whose genetic or pharmacologic suppression reduces metastases to bone but not to lungs. Together, these observations identify AR signaling in CTCs from women with bone-predominant ER + breast cancer, and provide a rationale for testing androgen inhibitors in this subset of patients. Implications: This study highlights a role for the AR in breast cancer bone metastasis, and suggests that therapeutic targeting of the AR may benefit patients with metastatic breast cancer. Mol Cancer Res; 16(4); 720-7. ©2018 AACR . ©2018 American Association for Cancer Research.

Jumps in binomial AR(1) processes

OpenAIRE

Weiß , Christian H.

2009-01-01

Abstract We consider the binomial AR(1) model for serially dependent processes of binomial counts. After a review of its definition and known properties, we investigate marginal and serial properties of jumps in such processes. Based on these results, we propose the jumps control chart for monitoring a binomial AR(1) process. We show how to evaluate the performance of this control chart and give design recommendations. correspondance: Tel.: +49 931 31 84968; ...

Single-electron capture into Ar+ excited states in Ar2 + Na collision below 12 keV, 1

International Nuclear Information System (INIS)

Matsumoto, Atsushi; Tsurubuchi, Seiji; Okuno, Kazuhiko; Ohtani, Shunsuke; Iwai, Tsuruji.

1979-08-01

Emission spectra between 2800 and 6000 A have been observed at the ionic energies from 0.2 to 12 keV. Absolute measurements of emission cross-sections have been made for the emission lines coming from ArII excited states at 4 and 8 keV with a crossed-beam technique. Processes of single-electron capture into the ArII 4p- and 4p'-states, with exothermicity of a few eV, take place dominantly (--10 15 cm 2 ), while the endothermic processes producing ArII in the 4d- and 5s-states occur with small cross-sections. Sum of the cross-sections for electron capture into the excited states observed is comparable with the total single-electron capture cross-section estimated from attenuation measurements of ion currents. Possible errors and uncertainties are discussed. (author)

Single-electron capture into Ar+ excited states in Ar2++Na collision below 12 keV, 1

International Nuclear Information System (INIS)

Matsumoto, Atsushi; Tsurubuchi, Seiji; Iwai, Tsuruji; Ohtani, Shunsuke; Okuno, Kazuhiko

1980-01-01

Emission spectra between 2800 and 6000 A have been observed at the ionic energies from 0.2 to 12 keV. Absolute measurements of emission cross-sections have been made for the emission lines coming from ArII excited states at 4 and 8 keV with a crossed-beam technique. Processes of single-electron capture into the ArII 4p- and 4p'-states, with exothermicity of a few eV, take place dominantly (--10 -15 cm 2 ), while the endothermic processes producing ArII in the 4d- and 5s-states occur with small cross-sections. Sum of the cross-sections for electron capture into the excited states observed is comparable with the total single-electron capture cross-section estimated from attenuation measurements of ion currents. Possible errors and uncertainties are discussed. (author)

Measurements of the 40Ar(n, γ41Ar radiative-capture cross section between 0.4 and 14.8 MeV

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Megha Bhike

2014-09-01

Full Text Available The 40Ar(n, γ41Ar neutron capture cross section has been measured between 0.4 and 14.8 MeV neutron energy using the activation technique. The data are important for estimating backgrounds in argon-based neutrino and dark-matter detectors and in the neutrino-less double-beta decay search GERDA, which uses liquid argon as cooling and shielding medium. For the first time the 40Ar(n, γ41Ar cross section has been measured for neutron energies above 1 MeV. Our results are compared to the evaluation ENDF/B-VII.1 and the calculated prediction TENDL-2013. The latter agrees very well with the present results.

Stilbene induced inhibition of androgen receptor dimerization: implications for AR and ARΔLBD-signalling in human prostate cancer cells.

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Wolfgang Streicher

Full Text Available BACKGROUND: Advanced castration resistant prostate cancer (CRPC is often characterized by an increase of C-terminally truncated, constitutively active androgen receptor (AR variants. Due to the absence of a ligand binding domain located in the AR-C-terminus, these receptor variants (also termed ARΔLBD are unable to respond to all classical forms of endocrine treatments like surgical/chemical castration and/or application of anti-androgens. METHODOLOGY: In this study we tested the effects of the naturally occurring stilbene resveratrol (RSV and (E-4-(2, 6-Difluorostyryl-N, N-dimethylaniline, a fluorinated dialkylaminostilbene (FIDAS on AR- and ARΔLBD in prostate cancer cells. The ability of the compounds to modulate transcriptional activity of AR and the ARΔLBD-variant Q640X was shown by reporter gene assays. Expression of endogenous AR and ARΔLBD mRNA and protein levels were determined by qRT-PCR and Western Blot. Nuclear translocation of AR-molecules was analyzed by fluorescence microscopy. AR and ARΔLBD/Q640X homo-/heterodimer formation was assessed by mammalian two hybrid assays. Biological activity of both compounds in vivo was demonstrated using a chick chorioallantoic membrane xenograft assay. RESULTS: The stilbenes RSV and FIDAS were able to significantly diminish AR and Q640X-signalling. Successful inhibition of the Q640X suggests that RSV and FIDAS are not interfering with the AR-ligand binding domain like all currently available anti-hormonal drugs. Repression of AR and Q640X-signalling by RSV and FIDAS in prostate cancer cells was caused by an inhibition of the AR and/or Q640X-dimerization. Although systemic bioavailability of both stilbenes is very low, both compounds were also able to downregulate tumor growth and AR-signalling in vivo. CONCLUSION: RSV and FIDAS are able to inhibit the dimerization of AR and ARΔLBD molecules suggesting that stilbenes might serve as lead compounds for a novel generation of AR-inhibitors.

Utah System of Higher Education 2015-16 Annual Report

Science.gov (United States)

Utah System of Higher Education, 2016

2016-01-01

This annual report describes Utah System of Higher Education's progress in the 2015-2016 academic year in the following areas: (1) Strategic plan; (2) Enrollment and completion; (3) Paying for college; (4) Funding higher education; (5) College preparation; (6) Concurrent enrollment and math; (7) Outreach and access; and (8) Industry and the…

Observation of a periodic runaway in the reactive Ar/O2 high power impulse magnetron sputtering discharge

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Seyedmohammad Shayestehaminzadeh

2015-11-01

Full Text Available This paper reports the observation of a periodic runaway of plasma to a higher density for the reactive discharge of the target material (Ti with moderate sputter yield. Variable emission of secondary electrons, for the alternating transition of the target from metal mode to oxide mode, is understood to be the main reason for the runaway occurring periodically. Increasing the pulsing frequency can bring the target back to a metal (or suboxide mode, and eliminate the periodic transition of the target. Therefore, a pulsing frequency interval is defined for the reactive Ar/O2 discharge in order to sustain the plasma in a runaway-free mode without exceeding the maximum power that the magnetron can tolerate.

Sensibility of different wheat varieties (strains) to Ar+ implantation

International Nuclear Information System (INIS)

Cui Huanhu; Jing Hua; Ma Aiping; Kang Xiuli; Yang Liping; Huang Mingjing; Ma Buzhou; Shanxi Academy of Agricultural Sciences, Taiyuan

2005-01-01

The sensibility of different wheat varieties (strains) to Ar + implantation was studied. The results showed that the survival rate of 21 wheat varieties (strains) at the dose of 6 x 10 16 Ar + /cm 2 could be divided into five groups: surplus sensitive varieties (strains), sensitive varieties (strains), transitional varieties (strains), obtuse varieties (strains) and surplus obtuse varieties (strains). The sensibility of wheat varieties (strains) to Ar + injection is high-moisture-fertility wheat varieties (strains) > medium-moisture-fertility wheat varieties (strains) > dry land wheat varieties (strains). The study has provided theoretical basis in induced mutation medial lethal dose of different wheat varieties (strains) to Ar + implantation. (authors)

AR-v7 protein expression is regulated by protein kinase and phosphatase

Science.gov (United States)

Li, Yinan; Xie, Ning; Gleave, Martin E.; Rennie, Paul S.; Dong, Xuesen

2015-01-01

Failure of androgen-targeted therapy and progression of castration-resistant prostate cancer (CRPC) are often attributed to sustained expression of the androgen receptor (AR) and its major splice variant, AR-v7. Although the new generation of anti-androgens such as enzalutamide effectively inhibits AR activity, accumulating pre-clinical and clinical evidence indicates that AR-v7 remains constitutively active in driving CRPC progression. However, molecular mechanisms which control AR-v7 protein expression remain unclear. We apply multiple prostate cancer cell models to demonstrate that enzalutamide induces differential activation of protein phosphatase-1 (PP-1) and Akt kinase depending on the gene context of cancer cells. The balance between PP-1 and Akt activation governs AR phosphorylation status and activation of the Mdm2 ubiquitin ligase. Mdm2 recognizes phosphorylated serine 213 of AR-v7, and induces AR-v7 ubiquitination and protein degradation. These findings highlight the decisive roles of PP-1 and Akt for AR-v7 protein expression and activities when AR is functionally blocked. PMID:26378044

The retinamide VNLG-152 inhibits f-AR/AR-V7 and MNK-eIF4E signaling pathways to suppress EMT and castration-resistant prostate cancer xenograft growth.

Science.gov (United States)

Ramamurthy, Vidya P; Ramalingam, Senthilmurugan; Gediya, Lalji K; Njar, Vincent C O

2018-03-01

VNLG-152 is a novel retinamide (NR) shown to suppress growth and progression of genetically diverse prostate cancer cells via inhibition of androgen receptor signaling and eukaryotic initiation factor 4E (eIF4E) translational machinery. Herein, we report therapeutic effects of VNLG-152 on castration-resistant prostate cancer (CRPC) growth and metastatic phenotype in a CRPC tumor xenograft model. Administration of VNLG-152 significantly and dose-dependently suppressed the growth of aggressive CWR22Rv1 tumors by 63.4% and 76.3% at 10 and 20 mg·kg -1 bw, respectively (P AR)/androgen receptor splice variant-7 (AR-V7), mitogen-activated protein kinase-interacting kinases 1 and 2 (MNK1/2), phosphorylated eIF4E and their associated target proteins, including prostate-specific antigen, cyclin D1 and Bcl-2, were strongly decreased in VNLG-152-treated tumors signifying inhibition of f-AR/AR-V7 and MNK-eIF4E signaling in VNLG-152-treated CWR22Rv1 tumors as observed in vitro. VNLG-152 also suppressed the epithelial to mesenchymal transition in CWR22Rv1 tumors as evidenced by repression of N-cadherin, β-catenin, claudin, Slug, Snail, Twist, vimentin and matrix metalloproteinases (MMP-2 and MMP-9) with upsurge in E-cadherin. These results highlight the promising use of VNLG-152 in CRPC therapy and justify its further development towards clinical trials. © 2018 Federation of European Biochemical Societies.

Dating quartz: Ar/Ar analyses of coexisting muscovite and fluid inclusion - rich quartz from paleocene amorphic aureole

International Nuclear Information System (INIS)

Matthews, S.J.; Perez de Arce, C.; Cornejo, P.; Cuitino, L; Klein, J

2001-01-01

We present Ar/Ar total fusion and step-heating data for coexisting muscovite and white quartz from the metamorphic aureole of the Lower Paleocene La Copiapina Pluton, 6 km south of Inca de Oro, III Region, Chile. The pluton intrudes the upper clastic sedimentary member of the Punta del Cobre Group (Upper Jurassic - Lower Cretaceous) and the calcareous sedimentary rocks of the Chanarcillo Group (Neocomian), and comprises fine to coarse grained pyroxene-hornblende-biotite quartz diorites and monzodiorites. Its emplacement was controlled on its north-western side by a subvertical NE-trending fault, along which were developed vertically banded skarns (skarn mylonite), suggesting syntectonic intrusion. Biotite K-Ar ages for the pluton fall in the range 61-63 Ma, relating it to a latest Cretaceous to Lowest Paleocene syn-compressional intrusive belt which is present in the area (Matthews and Cornejo, 2000). A metamorphic / metasomatic aureole is developed within the sandstones of the Punta del Cobre Group, on the extreme northern limit of the pluton. In this area, the sedimentary rocks have been replaced by quartz-sericite and quartz-muscovite assemblages, with minor hematite and tourmaline, and late supergene kaolinite and pyrophyllite. A coarse muscovite-quartz-tourmaline-hematite assemblage is developed in and around older (early Upper Cretaceous) andesitic dykes, in the form of replacement / fracture fill veins and replacement zones. Further from the contact with the pluton, fine-grained quartz-sericite rock with coarser muscovite-rich replacement veins represents the dominant lithology. Quartz in the coarse replacement rock is very rich in fluid inclusions. Primary inclusions are mainly of two coexisting types; bi-phase (liquid and gas bubble) and tri-phase (liquid, gas bubble and halite crystal), indicating that the quartz formed in the presence of a boiling fluid. Some inclusions also contain sylvite and occasional hematite daughter crystals. Secondary inclusions

Role of the two component signal transduction system CpxAR in conferring cefepime and chloramphenicol resistance in Klebsiella pneumoniae NTUH-K2044.

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Vijaya Bharathi Srinivasan

Full Text Available BACKGROUND: Klebsiella pneumoniae is a gram-negative, non-motile, facultative anaerobe belonging to the Enterobacteriaceae family of the γ-Proteobacteria class in the phylum Proteobacteria. Multidrug resistant K. pneumoniae have caused major therapeutic problems worldwide due to emergence of extended-spectrum β-lactamase producing strains. Two-component systems serve as a basic stimulus-response coupling mechanism to allow organisms to sense and respond to changes in many different environmental conditions including antibiotic stress. PRINCIPAL FINDINGS: In the present study, we investigated the role of an uncharacterized cpxAR operon in bacterial physiology and antimicrobial resistance by generating isogenic mutant (ΔcpxAR deficient in the CpxA/CpxR component derived from the hyper mucoidal K1 strain K. pneumoniae NTUH-K2044. The behaviour of ΔcpxAR was determined under hostile conditions, reproducing stresses encountered in the gastrointestinal environment and deletion resulted in higher sensitivity to bile, osmotic and acid stresses. The ΔcpxAR was more susceptible to β-lactams and chloramphenicol than the wild-type strain, and complementation restored the altered phenotypes. The relative change in expression of acrB, acrD, eefB efflux genes were decreased in cpxAR mutant as evidenced by qRT-PCR. Comparison of outer membrane protein profiles indicated a conspicuous difference in the knock out background. Gel shift assays demonstrated direct binding of CpxR(KP to promoter region of ompC(KP in a concentration dependent manner. CONCLUSIONS AND SIGNIFICANCE: The Cpx envelope stress response system is known to be activated by alterations in pH, membrane composition and misfolded proteins, and this systematic investigation reveals its direct involvement in conferring antimicrobial resistance against clinically significant antibiotics for the very first time. Overall results displayed in this report reflect the pleiotropic role of the CpxAR

75 FR 68416 - Establishment of Class E Airspace; Berryville, AR

Science.gov (United States)

2010-11-08

...-0690; Airspace Docket No. 10-ASW-2] Establishment of Class E Airspace; Berryville, AR AGENCY: Federal... for Berryville, AR, to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAP) at Carroll County Airport, Berryville, AR. The FAA is taking this action to enhance the safety...

76 FR 73505 - Establishment of Class E Airspace; Nashville, AR

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2011-11-29

...-0497; Airspace Docket No. 11-ASW-4] Establishment of Class E Airspace; Nashville, AR AGENCY: Federal... for Nashville, AR, to accommodate new Area Navigation (RNAV) Standard Instrument Approach Procedures... a notice of proposed rulemaking to amend Class E airspace for Nashville, AR, creating additional...

75 FR 29655 - Amendment of Class E Airspace; Batesville, AR

Science.gov (United States)

2010-05-27

...-1177; Airspace Docket No. 09-ASW-34] Amendment of Class E Airspace; Batesville, AR AGENCY: Federal... Batesville, AR. Decommissioning of the Independence County non-directional beacon (NDB) at Batesville Regional Airport, Batesville, AR, has made this action necessary to enhance the safety and management of...

Contribution of the 40Ar/39Ar method to improve Middle-Pleistocene archaeological/palaeontological sites from the Italian Peninsula

Science.gov (United States)

Nomade, Sebastien, ,, Dr.; Pereira, MSc. Alison; voinchet, Pierre, ,, Dr.; Bahain, Jean-Jacques, ,, Dr.; Aureli, Daniele, ,, Dr.; Arzarello, Marta, ,, Dr.; Anzidei, Anna-Paola, ,, Dr.; Biddittu, Italo, ,, Dr.; Bulgarelli, Maria-Grazia, ,, Dr.; Falguères, Christophe, ,, Dr.; Giaccio, Biagio, ,, Dr.; Guillou, Hervé, ,, Dr.; Manzi, Gorgio, ,, Dr.; Moncel, Marie-Hélène, ,, Dr.; Nicoud, Elisa, ,, Dr.; Pagli, Maria, ,, Dr.; Parenti, Fabio, ,, Dr.; Peretto, Carlo, ,, Dr.; Piperno, Marcello, ,, Dr.; Rocca, Roxane, ,, Dr.

2017-04-01

European Middle-Pleistocene archaeological and/or paleontological sites lack a unified and precise chronological framework. Despite recent efforts mostly focused on methods such as OSL, ESR/U-series or cosmogenic nuclides, the age of numerous sites from this period fundamentally still relies on qualitative and speculative palaeoenvironmental and/or palaeontological/palaeoanthropological considerations. The lack of robust chronologies, along with the scarcity of human fossils, prevent coherent correlations between European sites which in turn limits our understanding of human diffusion dynamics, understand techno-cultural evolution or correlate archaeological sites with palaeoclimatic and environmental records. With the goal of providing an accurate and precise chronological framework based on a multi-method approach, a research network including geochronologists, archaeologist and paleoanthropologists from various French and Italian institutions launched in 2010 a wide study of Middle-Pleistocene archaeological sites of central and southern Italy. This study combining the 39Ar/40Ar method with palaeo-dosimetric methods applied to European sites in the age range of 700 ka to 300 ka is unprecedented. In parallel, a large effort has been done to improve the regional Middle-Pleistocene tephrostratigraphic database through a massive application of both high-precision 40Ar/39Ar geochronological and geochemical investigations. We illustrate our approach and results in addressing several key-sites such as Notarchirico, Valle Giumentina; Ceprano-Campogrande and La Polledrara di Cecanibbio. The accurate and precise chronological framework we built permits us to replace all the investigated archaeological and palaeontological records into a coherent climatic and environmental context. Furthermore, our work provides the opportunity to compare lithic industries from a technical and evolutionary point of view within a homogeneous temporal frame. These preliminary results border

Problems in the K-Ar dating of Quaternary volcanic rocks younger than 1 Ma

International Nuclear Information System (INIS)

Takaoka, Nobuo

1989-01-01

The assumption that the 40 Ar/ 36 Ar ratio of Ar trapped in volcanic rocks at eruption is atmospheric often gives a large systematic error in the K-Ar dating of Quaternary volcanic rocks younger than 1 Ma. There are two possible sources of error, the existence of excess Ar and mass-fractionated, initial Ar. The major source of excess Ar is supposed to be magma. The 40 Ar/ 36 Ar ratio for magmatic Ar in the North-East Japan arc is tentatively estimated to be 340±10 from measurements of Ar in large phenocrysts separated from Quaternary volcanic rocks. Separation of phenocrysts is the most effective to decrease the systematic error caused by excess Ar. The mass-fractionation of initial Ar should give the 38 Ar/ 36 Ar ratio which was changed from the atmospheric ratio. This can be checked by determining the 38 Ar/ 36 Ar ratio in samples. Since the systematic error caused by the mass-fractionated, initial Ar increases greatly with the increasing atmospheric Ar correction, it is important to correct the result for the mass-fractionation. Correction formulae are given. The error sources other than those mentioned above are uncertainty in the blank correction and instabilities in the sensitivity of spectrometer and the Ar isotopic ratio measurement. In order to increase accuracy of the K-Ar age obtained, to check the systematic errors by measuring samples together with standard samples is of great importance in the K-Ar dating of very young volcanic rocks. (author)

arXiv ARS Leptogenesis

CERN Document Server

Drewes, M.; Hernandez, P.; Kekic, M.; Lopez-Pavon, J.; Racker, J.; Rius, N.; Salvado, J.; Teresi, D.

2018-02-28

We review the current status of the leptogenesis scenario originally proposed by Akhmedov, Rubakov and Smirnov (ARS). It takes place in the parametric regime where the right-handed neutrinos are at the electroweak scale or below and the CP-violating effects are induced by the coherent superposition of different right-handed mass eigenstates. Two main theoretical approaches to derive quantum kinetic equations, the Hamiltonian time evolution as well as the Closed-Time-Path technique are presented, and we discuss their relations. For scenarios with two right-handed neutrinos, we chart the viable parameter space. Both, a Bayesian analysis, that determines the most likely configurations for viable leptogenesis given different variants of flat priors, and a determination of the maximally allowed mixing between the light, mostly left-handed, and heavy, mostly right-handed, neutrino states are discussed. Rephasing invariants are shown to be a useful tool to classify and to understand various distinct contributions to...

40Ar/39Ar incremental-release ages of biotite from a progressively remetamorphosed Archean basement terrane in southwestern Labrador

International Nuclear Information System (INIS)

Dallmeyer, R.D.

1982-01-01

Gneisses within Archean basement terrane adjacent to the southwestern portion of the Labrador Trough were variably retrograded during a regional metamorphism of Grenville age (ca. 1000 Ma). Bioties from non-retrograded segments of the gneiss terrane record 40 Ar/ 39 Ar plateau and isochron ages which date times of cooling following an episode of the Kenoran orogeny (2376-2391 Ma). A suite of gneiss samples displaying varying degrees of retrograde alteration was collected across the Grenville metamorphic gradient. Bioties in these samples show no petrographic evidence of retrograde alteration, however they do record internally discordant 40 Ar/ 39 Ar age spectra. Although the extent of internal discordance is variable, the overall character of the release patterns is similar with younger apparent ages recorded in intermediate-temperature gas fractions. The total-gas dates range from 2257+-27 Ma (northwest) to 1751+-23 Ma (southeast), suggesting that variable quantities of radiogenic argon were lost from the Archean biotites during Grenville metamorphism. The 'saddle-shaped' nature of the discordant spectra indicates that argon loss was not accomplished through single-stage, volume diffusion processes. (orig./ME)

Ar-40/Ar-39 age determinations for the Rotoiti eruption, New Zealand

Science.gov (United States)

Flude, S.; Storey, M.

2013-12-01

The contemporaneous Rotoiti and Earthquake Flat ignimbrites, erupted from the Taupo Volcanic zone, New Zealand, form a distinctive tephrostratigraphic horizon in the Southern Pacific. Radioisotopic dating results for these eruptions remain controversial, with published ages ranging from 35.1 × 2.8 ka [1] to 71 × 6 ka [2], with 61.0 × 1.5 ka [3] often being cited as the most widely accepted age. These eruptions are difficult to date as their age is near the limit for various radiometric dating techniques, which are complicated by a large proportion of inherited material (xenocrysts) and a lack of phases suitable for dating. Glass-bearing plutonic blocks erupted with the Rotoiti and Earthquake Flat ignimbrites have previously been interpreted as deriving from a slowly cooled and incompletely solidified magma body that was sampled by the eruptions. They contain large vugs lined with euhedral quartz, sanidine and biotite crystals, indicating that these crystals grew in a gas or aqueous fluid rich environment and are interpreted to have formed shortly before or during eruption. Here we will present Ar-40/Ar-39 ages for sanidines and biotites extracted from vugs in lithic blocks erupted as part of the Earthquake Flat ignimbrite. We show that, even for vug-lining material, inherited ages remain a problem and are the likely source of the wide variation in published radiometric ages. Nevertheless, many of the Ar-40/Ar-39 ages are much younger than the 61 ka age [3] and are more consistent with the recent stratigraphic, C-14 and U-238/Th-230+(U-Th)/He ages that have been suggested (e.g. [4,5]). 1. Whitehead, N. & Ditchburn, R. New Zealand Journal of Geology and Geophysics 37, 381-383 (1994). 2. Ota, Y., Omura, A. & Iwata, H. New Zealand Journal of Geology and Geophysics 32, 327-331 (1989). 3. Wilson, C. J. N. et al. Quaternary Science Reviews 26, 1861-1870 (2007). 4. Molloy, C., Shane, P. & Augustinus, P. Geological Society of America Bulletin 121, 1666-1677 (2009). 5

AR-NE3A, a New Macromolecular Crystallography Beamline for Pharmaceutical Applications at the Photon Factory

International Nuclear Information System (INIS)

Yamada, Yusuke; Hiraki, Masahiko; Sasajima, Kumiko; Matsugaki, Naohiro; Igarashi, Noriyuki; Kikuchi, Takashi; Mori, Takeharu; Toyoshima, Akio; Kishimoto, Shunji; Wakatsuki, Soichi; Amano, Yasushi; Warizaya, Masaichi; Sakashita, Hitoshi

2010-01-01

Recent advances in high-throughput techniques for macromolecular crystallography have highlighted the importance of structure-based drug design (SBDD), and the demand for synchrotron use by pharmaceutical researchers has increased. Thus, in collaboration with Astellas Pharma Inc., we have constructed a new high-throughput macromolecular crystallography beamline, AR-NE3A, which is dedicated to SBDD. At AR-NE3A, a photon flux up to three times higher than those at existing high-throughput beams at the Photon Factory, AR-NW12A and BL-5A, can be realized at the same sample positions. Installed in the experimental hutch are a high-precision diffractometer, fast-readout, high-gain CCD detector, and sample exchange robot capable of handling more than two hundred cryo-cooled samples stored in a Dewar. To facilitate high-throughput data collection required for pharmaceutical research, fully automated data collection and processing systems have been developed. Thus, sample exchange, centering, data collection, and data processing are automatically carried out based on the user's pre-defined schedule. Although Astellas Pharma Inc. has a priority access to AR-NE3A, the remaining beam time is allocated to general academic and other industrial users.

78 FR 41838 - Establishment of Class E Airspace; Colt, AR

Science.gov (United States)

2013-07-12

...-1281; Airspace Docket No. 12-ASW-13] Establishment of Class E Airspace; Colt, AR AGENCY: Federal... at Colt, AR. Controlled airspace is necessary to accommodate new Area Navigation (RNAV) Standard... Federal Register a notice of proposed rulemaking (NPRM) to establish Class E airspace for the Colt, AR...

75 FR 29657 - Establishment of Class E Airspace; Marianna, AR

Science.gov (United States)

2010-05-27

...-1167; Airspace Docket No. 09-ASW-33] Establishment of Class E Airspace; Marianna, AR AGENCY: Federal... for Marianna, AR to accommodate Area Navigation (RNAV) Standard Instrument Approach Procedures (SIAPs) at Marianna/Lee County Airport--Steve Edwards Field, Marianna, AR. The FAA is taking this action to...

75 FR 29656 - Amendment of Class E Airspace; Magnolia, AR

Science.gov (United States)

2010-05-27

...-1179; Airspace Docket No. 09-ASW-35] Amendment of Class E Airspace; Magnolia, AR AGENCY: Federal... airspace for Magnolia, AR. Decommissioning of the Magnolia non-directional beacon (NDB) at Magnolia Municipal Airport, Magnolia, AR has made this action necessary to enhance the safety and management of...

75 FR 37291 - Amendment of Class E Airspace; Osceola, AR

Science.gov (United States)

2010-06-29

...-1183; Airspace Docket No. 09-ASW-38] Amendment of Class E Airspace; Osceola, AR AGENCY: Federal... Osceola, AR. Decommissioning of the Osceola non-directional beacon (NDB) at Osceola Municipal Airport has... rulemaking to amend Class E airspace for Osceola, AR, reconfiguring controlled airspace at Osceola Municipal...

Exhumation history of the NW Indian Himalaya revealed by fission track and 40Ar/39Ar ages

Science.gov (United States)

Schlup, Micha; Steck, Albrecht; Carter, Andrew; Cosca, Michael; Epard, Jean-Luc; Hunziker, Johannes

2011-01-01

New fission track and Ar/Ar geochronological data provide time constraints on the exhumation history of the Himalayan nappes in the Mandi (Beas valley) — Tso Morari transect of the NW Indian Himalaya. Results from this and previous studies suggest that the SW-directed North Himalayan nappes were emplaced by detachment from the underthrusted upper Indian crust by 55 Ma and metamorphosed by ca. 48–40 Ma. The nappe stack was subsequently exhumed to shallow upper crustal depths (

Aegeline inspired synthesis of novel β3-AR agonist improves insulin sensitivity in vitro and in vivo models of insulin resistance.

Science.gov (United States)

Rajan, Sujith; Satish, Sabbu; Shankar, Kripa; Pandeti, Sukanya; Varshney, Salil; Srivastava, Ankita; Kumar, Durgesh; Gupta, Abhishek; Gupta, Sanchita; Choudhary, Rakhi; Balaramnavar, Vishal M; Narender, Tadigoppula; Gaikwad, Anil N

2018-03-07

In our drug discovery program of natural product, earlier we have reported Aegeline that is N-acylated-1-amino-2- alcohol, which was isolated from the leaves of Aeglemarmelos showed anti-hyperlipidemic activity for which the QSAR studies predicted the compound to be the β3-AR agonist, but the mechanism of its action was not elucidated. In our present study, we have evaluated the β3-AR activity of novel N-acyl-1-amino-3-arylopropanol synthetic mimics of aegeline and its beneficial effect in insulin resistance. In this study, we have proposed the novel pharmacophore model using reported molecules for antihyperlipidemic activity. The reported pharmacophore features were also compared with the newly developed pharmacophore model for the observed biological activity. Based on 3D pharmacophore modeling of known β3AR agonist, we screened 20 synthetic derivatives of Aegeline from the literature. From these, the top scoring compound 10C was used for further studies. The in-slico result was further validated in HEK293T cells co-trransfected with human β3-AR and CRE-Luciferase reporter plasmid for β3-AR activity.The most active compound was selected and β3-AR activity was further validated in white and brown adipocytes differentiated from human mesenchymal stem cells (hMSCs). Insulin resistance model developed in hMSC derived adipocytes was used to study the insulin sensitizing property. 8 week HFD fed C57BL6 mice was given 50 mg/Kg of the selected compound and metabolic phenotyping was done to evaluate its anti-diabetic effect. As predicted by in-silico 3D pharmacophore modeling, the compound 10C was found to be the most active and specific β3-AR agonist with EC 50 value of 447 nM. The compound 10C activated β3AR pathway, induced lipolysis, fatty acid oxidation and increased oxygen consumption rate (OCR) in human adipocytes. Compound 10C induced expression of brown adipocytes specific markers and reverted chronic insulin induced insulin resistance in white

Absolute timing of sulfide and gold mineralization: A comparison of Re-Os molybdenite and Ar-Ar mica methods from the Tintina Gold Belt, Alaska

Science.gov (United States)

Selby, D.; Creaser, R.A.; Hart, C.J.R.; Rombach, C.S.; Thompson, J.F.H.; Smith, Moira T.; Bakke, A.A.; Goldfarb, R.J.

2002-01-01

New Re-Os molybdenite dates from two lode gold deposits of the Tintina Gold Belt, Alaska, provide direct timing constraints for sulfide and gold mineralization. At Fort Knox, the Re-Os molybdenite date is identical to the U-Pb zircon age for the host intrusion, supporting an intrusive-related origin for the deposit. However, 40Ar/39Ar dates from hydrothermal and igneous mica are considerably younger. At the Pogo deposit, Re-Os molybdenite dates are also much older than 40Ar/39Ar dates from hydrothermal mica, but dissimilar to the age of local granites. These age relationships indicate that the Re-Os molybdenite method records the timing of sulfide and gold mineralization, whereas much younger 40Ar/39Ar dates are affected by post-ore thermal events, slow cooling, and/or systemic analytical effects. The results of this study complement a growing body of evidence to indicate that the Re-Os chronometer in molybdenite can be an accurate and robust tool for establishing timing relations in ore systems.

75 FR 12161 - Establishment of Class E Airspace; Marianna, AR

Science.gov (United States)

2010-03-15

...-1167; Airspace Docket No. 09-ASW-33] Establishment of Class E Airspace; Marianna, AR AGENCY: Federal... proposes to establish Class E airspace at Marianna/Lee County Airport-Steve Edwards Field, Marianna, AR, to... operations at Marianna/Lee County Airport-Steve Edwards Field, Marianna, AR. Controlled airspace is needed...

Field safety notices released by manufacturers in cases of failure of products for infection testing: analysis of cases reported to the BfArM between 2005 and 2007.

Science.gov (United States)

Siekmeier, R; Lisson, K; Wetzel, D

2010-11-04

The European Directive 98/79/EC for in vitro diagnostic medical devices (IVD) regulates marketing and post marketing surveillance of IVD in the European Economic Area. Manufacturers have to inform the responsible Competent Authorities (CA) about incidents and field safety corrective actions (FSCA) related to IVD. In Germany, the Federal Institute for Drugs and Medical Devices (BfArM) is the responsible CA for most IVD, only few IVD as specified in Annex II of the Directive are under the responsibility of the Paul Ehrlich Institute (PEI). In case of a FSCA manufacturers have to inform customers by means of a Field Safety Notice (FSN) which should be sent to BfArM prior to release and is published on the BfArM homepage. Between beginning of 2005 and end of 2007 the BfArM received a total of 1025 reports regarding IVD. From these, 38 related to tests, reagents, calibrators, and control materials for infection testing, 13 related to analysers and general consumables (n = 8 and n = 5, respectively) based on culture techniques, and 7 related to analysers and general consumables (n = 5 and n = 2, respectively) based on molecular biological methods. FSCA were performed in Germany in 32 (84.2%) of all notifications related to tests reagents, calibrators, and control materials as well as in 13 (100%) and 7 (100%) of notifications related to analysers and consumables based on culture techniques and molecular biological methods, respectively. A number of relevant deficiencies regarding the quality of the FSN were separately demonstrated for FSN in German and English language. In brief, manufacturers often sent their FSN to the BfArM with delay. Additionally, a subset of FSN provided insufficient information on the product related risks or the measures to be performed by the customer to mitigate product related risks. Furthermore, customer confirmation forms often were missing in the FSN sent to the BfArM. Our data suggest that for IVD for infection testing FSCA and FSN are

Larvicidal and Biting Deterrent Activity of Essential Oils of Curcuma longa, Ar-turmerone, and Curcuminoids Against Aedes aegypti and Anopheles quadrimaculatus (Culicidae: Diptera).

Science.gov (United States)

Ali, Abbas; Wang, Yan-Hong; Khan, Ikhlas A

2015-09-01

Essential oils and extract of Curcuma longa, ar-turmerone, and curcuminoids were evaluated for their larvicidal and deterrent activity against mosquitoes. Ar-turmerone and curcuminoids constituted 36.9, 24.9 and 50.6% of rhizome oil, leaf oil, and rhizome extract, respectively. Ar-turmerone was the major compound of the rhizome oil (36.9%) and leaf oil (24.9%). The ethanolic extract had 15.4% ar-turmerone with 6.6% bisdesmethoxycurcumin, 6.1% desmethoxycurcumin, and 22.6% curcumin. In in vitro studies, essential oils of the leaf (biting deterrence index [BDI] = 0.98), rhizome (BDI = 0.98), and rhizome ethanolic extract (BDI = 0.96) at 10 µg/cm(2) showed biting deterrent activity similar to DEET at 25 nmol/cm(2) against Aedes aegypti L. Among the pure compounds, ar-turmerone (BDI = 1.15) showed the biting deterrent activity higher than DEET at 25 nmol/cm(2) whereas the activity of other compounds was lower than DEET. In Anopheles quadrimaculatus Say, only ar-turmerone showed deterrent activity similar to DEET. In dose-response bioassay, ar-turmerone showed significantly higher biting deterrence than DEET at all the dosages. Ar-turmerone, at 15 nmol/cm(2), showed activity similar to DEET at 25 nmol/cm(2) and activity at 5 nmol/cm(2) was similar to DEET at 20 and 15 nmol/cm(2). Leaf essential oil with LC(50) values of 1.8 and 8.9 ppm against larvae of An. quadrimaculatus and Ae. aegypti, respectively, showed highest toxicity followed by rhizome oil and ethanolic extract. Among the pure compounds, ar-turmerone with LC(50) values of 2.8 and 2.5 ppm against larvae of An. quadrimaculatus and Ae. aegypti, respectively, was most toxic followed by bisdesmethoxycurcumin, curcumin, and desmethoxycurcumin. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Potential hydroxyl ultraviolet laser. [Ar-H/sub 2/O

Energy Technology Data Exchange (ETDEWEB)

Chen, C H; Payne, M G

1976-09-01

A strong emission band extending from 3060 to 3120 A was observed following proton beam excitation of an Ar--H/sub 2/O mixture. This emission band was assigned to the transition of OH(A/sup 2/Sigma/sup +/)/sub nu=o/ ..-->.. OH(X/sup 2/Pi)/sub nu=o/. At high argon partial pressure (> 200 torr), the precursor of this emission band is believed to be the argon excimer Ar/sup *//sub 2/(1/sub u/). The fluorescence efficiency of Ar--H/sub 2/O is estimated to be a factor of 4 times that of Ar--N/sub 2/. Development of a highly efficient, tunable uv laser by e-beam pumping is promising.

A phase one AR/C system design

Science.gov (United States)

Kachmar, Peter M.; Polutchko, Robert J.; Matusky, Martin; Chu, William; Jackson, William; Montez, Moises

1991-01-01

The Phase One AR&C System Design integrates an evolutionary design based on the legacy of previous mission successes, flight tested components from manned Rendezvous and Proximity Operations (RPO) space programs, and additional AR&C components validated using proven methods. The Phase One system has a modular, open architecture with the standardized interfaces proposed for Space Station Freedom system architecture.

The beta decay asymmetry parameter of 35Ar

International Nuclear Information System (INIS)

Garnett, J.D.

1987-11-01

The beta decay asymmetry parameter for 35 Ar = 35 Cl + e + + nu/sub e/ has been remeasured in order to resolve a long standing puzzle. Previous asymmetry measurements, when combined with the comparative half-life, yield a value for the vector coupling constant, G/sub v/, that is in serious disagreement with the accepted value. We produced polarized 35 Ar by a (p,n) reaction on 35 Cl using the polarized proton beam provided by Lawrence Berkeley Laboratory's 88-Inch Cyclotron. The polarization of the 35 Ar was determined by measuring the asymmetry of the positrons produced in 35 Ar decay to the first excited state in 35 Cl (branching ratio = 1.3%) in coincidence with a 1219.4 keV gamma ray. Our result, A 0 = 0.49 +- 0.10, combined with the comparative half-life yields a value for G/sub v/ in agreement with the accepted value

Geochemistry and 40Ar/39Ar age of Early Carboniferous dolerite sills in the southern Baltic Sea

Directory of Open Access Journals (Sweden)

Gediminas Motuza

2015-08-01

Full Text Available The Early Carboniferous magmatic event in the southern Baltic Sea is manifested by dolerite intrusions. The presumable area in which the dolerite intrusions occur ranges from 30 to 60 km in east–west direction, and is about 100 km in north–south direction. The dolerites were sampled in well D1-1 and investigated by applying chemical analysis and 40Ar/39Ar step-heating dating. Dolerites are classified as alkali and sodic, characterized by high TiO2 (3.92, 3.99 wt% and P2O5 (1.67, 1.77 wt% and low MgO (4.89, 4.91 wt% concentrations, enriched in light rare earth elements, originated from an enriched mantle magma source and emplaced in a continental rift tectonic setting. The 351 ± 11 Ma 40Ar/39Ar plateau age for groundmass plagioclase indicates a considerable age gap with the 310–250 Ma magmatism in southern Scandinavia and northern Germany. The magmatic rocks in the Baltic Sedimentary Basin are coeval with alkaline intrusions of NE Poland. Both magmatic provinces lie in the northwestward prolongation of the Pripyat–Dnieper–Donetsk Rift (370–359 Ma and may constitute a later phase of magmatic activity of this propagating rift system.

Ar-Ar Ages of Nakhlites Y000593, NWA998, and Nakhla and CRE Age of NWA998.

Science.gov (United States)

Garrison, D. H.; Bogard, D. D.

2006-01-01

The seven known Martian nakhlites are Nakhla, Lafayette, Governador Valadares, and four recent finds from hot and cold deserts: MIL03346 from the Transantarctic Mountains, a paired group from the Yamato Mountains (Y000593, Y000749, and Y000802; 1), and two from Morocco (NWA998 and NWA817; 2). Radiometric ages (Sm-Nd, Rb-Sr, U-Pb, and Ar-Ar) for the first three nakhlites, along with Chassigny, fall in the range of 1.19-1.37 Gyr and may suggest a common formation age (e.g., 3). These meteorites also show very similar cosmic-ray (space) exposure ages, which suggests a single ejection event from Mars (3). The ages for nakhlites are different from those of Martian shergottites, whose radiometric ages vary by nearly a factor of three (approximately 165-475 Myr) and whose space exposure ages vary over a factor of approximately 20 (3). Shergottite ages suggest that multiple locations on the Martian surface have been sampled, whereas nakhlite data imply that only one Mars surface location has been sampled. Because older Martian surfaces are expected to be more abundant, it seems surprising that all nakhlites would represent only one Martian impact event. To address this issue, we are measuring the Ar-39-Ar-40 ages of Y-000593, NWA-998, Nakhla, and MIL-03346, and the space (CRE) exposure age of NWA998.

Ar-Ar Ages of Nakhlites Y000593, NWA998, and Nakhla and CRE Ages of NWA998

Science.gov (United States)

Garrison, D. H.; Bogard, D. D.

2005-01-01

The seven known Martian nakhlites are Nakhla, Lafayette, Governador Valadares, and four recent finds from hot and cold deserts: MIL03346 from the Transantarctic Mountains, a paired group from the Yamato Mountains (Y000593, Y000749, and Y000802, and two from Morocco (NWA998 and NWA817. Radiometric ages (Sm-Nd, Rb-Sr, U-Pb, and Ar-Ar) for the first three nakhlites, along with Chassigny, fall in the range of 1.19-1.37 Gyr and may suggest a common formation age. These meteorites also show very similar cosmic-ray (space) exposure ages, suggesting a single ejection event from Mars. The ages for nakhlites are different from those of Martian shergottites, whose radiometric ages vary by nearly a factor of three (approx. 165-475 Myr) and whose space exposure ages vary over a factor of approx. 20. Shergottite ages suggest that multiple locations on the Martian surface have been sampled, whereas nakhlite data imply sampling of only one Mars surface location. Because older Martian surfaces are expected to be more abundant, it seems surprising that all nakhlites would represent only one Martian impact event. To address this issue, we are measuring the (39)Ar-(40)Ar ages of Y-000593, NWA-998, Nakhla, and MIL-03346, and the space (CRE) exposure age of NWA998. Additional information is included in the original extended abstract.

Re-measurement of $^{32}$Ar to test the IMME

CERN Multimedia

The Isobaric Multiplet Mass Equation (IMME) has been subject to extensive studies in the low-mass region. Especially at the A = 32 quintet, the predicted quadratic form could not be confirmed, possible explanations being the insufficient accuracy of input parameters or higher-order interactions within the nucleon. For this quintet, the uncertainty on the mass-excess values of four of the five T = 2 multiplet members is extremely low: 0.6 keV for $^{32}$Cl, 0.3 keV for $^{32}$S, 0.2 keV for $^{32}$P, and 0.7 keV for $^{32}$Si. In the case of $^{32}$Ar, however, the uncertainty is as large as 1.8 keV. State-of-the-art high-precision Penning-trap mass spectrometry makes it possible to decrease this uncertainty. We propose to remeasure the mass of $^{32}$Ar at the Penning-trap mass spectrometer ISOLTRAP thus decreasing the uncertainty by a factor of 3-5. The proposed measurement is part of an experimental collaboration with JYFLTRAP, where the remaining masses of the T = 2 isospin quintet at A = 32 will be remeas...

CX4945 suppresses the growth of castration-resistant prostate cancer cells by reducing AR-V7 expression.

Science.gov (United States)

Deng, Chuangzhong; Chen, Jieping; Guo, Shengjie; Wang, Yanjun; Zhou, Qianghua; Li, Zaishang; Yang, Xingping; Yu, Xingsu; Zhang, Zhenfeng; Zhou, Fangjian; Han, Hui; Yao, Kai

2017-08-01

The aberrant expression of casein kinase 2 (CK2) has been reported to be involved in the tumorigenesis and progression of prostate cancer. The inhibition of CK2 activity represses androgen-dependent prostate cancer cells by attenuating the androgen receptor (AR) signaling pathway. In this study, we examined the effect of CK2 inhibition in castration-resistant prostate cancer (CRPC) cells, in which AR variants (ARVs) play a predominant role. A newly synthetic CK2 selective inhibitor CX4945 was utilized to study the effect of CK2 inhibition in CRPC cells by CCK8 assay and colony formation assay. Protein and mRNA levels of full-length AR (AR-FL) and AR-V7 were determined by qPCR and western blot, respectively. The nuclear translocation of p50 and p65 was assessed to reflect the activity of the NF-κB pathway. CX4945 reduced the proliferation of CRPC cells in a dose-dependent and time-dependent manner. AR-V7 rather than AR-FL was downregulated by CX4945 in both the mRNA and protein level. Furthermore, CX4945 could restore the sensitivity of CRPC cells to bicalutamide. The analysis of possible mechanisms demonstrated that the inhibition of CK2 diminished the phosphorylation of p65 at ser529 and thus attenuated the activity of the NF-κB pathway. The inhibition of CK2 by CX4945 can repress the viability of CRPC cells and restore their sensitivity to anti-androgen therapy by suppressing AR-V7. This finding presents a potential option for the treatment of prostate cancer, especially CRPC.

Revisions of K/Ar ages for the Hadar hominid site, Ethiopia

Energy Technology Data Exchange (ETDEWEB)

Walter, R.C.; Aronson, J.L. (Case Western Reserve Univ., Cleveland, OH (USA). Dept. of Geology)

1982-03-11

Conventional K/Ar age measurements are reported for two volcanic units from the hominid-bearing Hadar Formation. These ages represent revision of previously published ages for the BKT-2 tephra and the Kadada Moumou basalt. BKT-2 is revised from 2.65 to 2.9 Myr BP and the Kadada Moumou basalt is revised from 3.0 to 3.6 Myr BP.

Higher mortality of adults with asthma: A 15-year follow-up of a population-based cohort.

Science.gov (United States)

Lemmetyinen, R E; Karjalainen, J V; But, A; Renkonen, R L O; Pekkanen, J R; Toppila-Salmi, S K; Haukka, J K

2018-02-20

Higher all-cause mortality in asthmatics has been shown previously. Polysensitization is associated with higher morbidity among asthmatic children, and allergic rhinitis and/or allergic conjunctivitis (AR/AC) are associated with higher morbidity in adult asthmatics. Little is known about the effect of AR/AC and other factors on mortality among adult asthmatics. The aim was to study mortality and its risk factors in adults with and without asthma. We randomly selected 1648 asthmatics with age over 30 years from national registers and matched the asthma sample with one or two controls. Baseline information was obtained by a questionnaire in 1997, and the study population was linked with the death certificate information of Statistics Finland from 1997 to 2013. Overall and cause-specific survival between the groups was compared in several adjusted models. During a mean follow-up period of 15.6 years, 221 deaths among 1052 asthma patients and 335 deaths among 1889 nonasthmatics were observed. Cardiovascular diseases were the main cause of death in both groups. Asthma was associated with increased all-cause mortality (adjusted HR 1.25; 95% CI 1.05-1.49, P = .011) as well as mortality from chronic obstructive pulmonary disease (HR 12.0, 4.18-34.2, P < .001) and malignant neoplasms of respiratory organs (HR 2.33, 1.25-4.42, P = .008). Among asthmatics, smoking was associated with increased all-cause mortality, and self-reported AR/AC was associated with decreased mortality. Among nonasthmatics, smoking, and obesity were associated with increased all-cause mortality, whereas female gender showed an association with a decreased risk. Increased mortality among adult asthmatics was largely explained by the development of COPD, malignant respiratory tract neoplasms, and cardiovascular diseases. Smoking cessation is important for reduction in total mortality in both asthmatic and nonasthmatic adults. AR/AC was associated with decreased mortality only in asthmatics. Thus

75 FR 66300 - Amendment of Class E Airspace; Searcy, AR

Science.gov (United States)

2010-10-28

...-1182; Airspace Docket No. 09-ASW-37] Amendment of Class E Airspace; Searcy, AR AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace for Searcy, AR. Decommissioning of the Searcy non-directional beacon (NDB) at Searcy Municipal Airport, Searcy, AR, has made this...

75 FR 29654 - Amendment of Class E Airspace; Manila, AR

Science.gov (United States)

2010-05-27

...-1184; Airspace Docket No. 09-ASW-39] Amendment of Class E Airspace; Manila, AR AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action amends Class E airspace for Manila, AR. Decommissioning of the Manila non-directional beacon (NDB) at Manila Municipal Airport, Manila, AR has made this...

Noninvasive Detection of AR-FL/AR-V7 as a Predictive Biomarker for Therapeutic Resistance in Men with Metastatic Castration-Resistant Prostate Cancer

Science.gov (United States)

2017-10-01

acknowledged federal support) 5. Antonarakis ES, Armstrong AJ, Dehm SM, Luo J. Androgen receptor variant-driven prostate cancer : clinical implications...Resistant Prostate Cancer abstract Purpose A splice variant of the androgen receptor , AR-V7, confers resistance to AR-targeted therapies (ATTs) but not...androgen receptor ; AR-V7, androgen receptor splice variant 7; mCRPC, metastatic castration-resistant prostate cancer ; n/N, number of patients in that

XRD-based 40Ar/39Ar age correction for fine-grained illite, with application to folded carbonates in the Monterrey Salient (northern Mexico)

Science.gov (United States)

Fitz-Díaz, Elisa; Hall, Chris M.; van der Pluijm, Ben A.

2016-05-01

Due to their minute size, 40Ar/39Ar analysis of illite faces significant analytical challenges, including mineral characterization and, especially, effects of grain size and crystallography on 39Ar recoil. Quantifying the effects of 39Ar recoil requires the use of sample vacuum encapsulation during irradiation, which permits the measurement of the fraction of recoiled 39Ar as well as the 39Ar and 40Ar∗ retained within illite crystals that are released during step heating. Total-Gas Ages (TGA) are calculated by using both recoiled and retained argon, which is functionally equivalent to K-Ar ages, while Retention Ages (RA) only involve retained Ar in the crystal. Natural applications have shown that TGA fits stratigraphic constraints of geological processes when the average illite crystallite thickness (ICT) is smaller than 10 nm, and that RA matches these constraints for ICTs larger than 50 nm. We propose a new age correction method that takes into account the average ICT and corresponding recoiled 39Ar for a sample, with X-ray Corrected Ages (XCA) lying between Total-Gas and Retention Ages depending on ICT. This correction is particularly useful in samples containing authigenic illite formed in the anchizone, with typical ICT values between 10 and 50 nm. In three samples containing authigenic illite from Cretaceous carbonates in the Monterrey Salient in northern Mexico, there is a range in TGAs among the different size-fractions of 46-49, 36-43 and 40-52 Ma, while RAs range from 54-64, 47-52 and 53-54 Ma, respectively. XCA calculations produce tighter age ranges for these samples of 52.5-56, 45.5-48.5 and 49-52.5 Ma, respectively. In an apparent age vs ICT or %2M 1illite plot, authigenic illite grains show a slope that is in general slightly positive for TGA, slightly negative for RA, but close to zero for XCA, with thinner crystallites showing more dispersion than thicker ones. In order to test if dispersion is due to a different formation history or the result

40Ar-39Ar laser probe dating of individual clinopyroxene inclusions in Premier eclogitic diamonds

International Nuclear Information System (INIS)

Burgess, R.; Turner, G.; Laurenzi, M.; Harris, J.W.

1989-01-01

The ages of seven individual clinopyroxene inclusions in Premier diamonds of eclogitic association have been determined using the 40 Ar- 39 Ar dating technique. Syngenetic inclusions weighing between 10 and 130 μg were exposed on cleaved surfaces of the diamonds and analysed using a laser probe. The inclusion ages were found to be in the range 1111±35 to 1254±38 Ma with an average of 1185±94 Ma. The ages obtained are in good agreement with previous determinations made on aggregates of eclogitic inclusions from Premier diamonds and demonstrate the applicability of the laser probe to dating individual diamond inclusions. (orig.)

Piesaistes stila saistība ar apmierinātību ar dzīvi

OpenAIRE

Čiekure, Līva

2015-01-01

Pētījuma mērķis ir noskaidrot vai pastāv saistības starp piesaistes stilu un apmierinātību ar dzīvi. Tika aptaujāti 100 respondenti- 50 sievietes un 50 vīrieši. Pētījumā tika izmantotas Piesaistes stilu aptauja (Attachment Styles -Inventory /ASI/, Sperling & Berman, 1991), Latvijā adaptējusi Baiba Martinsone (2003) un Apmierinātības ar dzīvi aptauja ( Satisfaction with life scales,/SWLS/, Diener, 1985), Latvijā adaptēja Maslovska, Voitkāne, Miezīte & Raščevska ( 2005) un Upmane (Upmane, 2010)...

40Ar/39Ar dates in the Central Cordillera of Colombia: Evidence for an upper triassic regional tecnomagmatic event

International Nuclear Information System (INIS)

Vinasco, C.J.; Cordani, U.G.; Vasconcelos, P

2001-01-01

The Coastal, Western, Central and the Eastern Cordilleras constitute four independent mountain ranges in the Northern Andes. The Coastal and Western Cordillera comprises allochthonous oceanic sequences of basic volcanic rocks and marine sediments of Cenozoic and Upper Cretaceous age (Aspden et al., 1987). The so-called Central Cordillera Polymetamorphic Complex (Restrepo and Toussaint, 1982), made up the pre-Mesozoic Central Cordillera basement, consists of low through high-grade metamorphic rocks intruded by Meso-Cenozoic batholiths. The Eastern Cordillera is a polydeformed continental mountain range consisting of Precambrian and Paleozoic metamorphic and igneous rocks overlain by Paleozoic to Mesozoic sedimentary covers. The northern part of the Central Cordillera has been described as a suspect terrain affected by several tectonometamorphic episodes. The most important of them have been always considered those related to the Hercynian orogeny, in Devonian and Carboniferous times, and those occurring at the beginning of the Andean Cycle in the Cretaceous (Restrepo and Toussaint, 1982). A possible Lower Paleozoic and even Precambrian age for the basement of the terrain has also been proposed. Although some indications of a Permo-Triassic event are already available, this period was not considered as of great importance for the geologic evolution of the region. The available radiometric dates in the 200-250 Ma interval, for the Central Cordillera, are as follows: 1. One K-Ar whole rock age for a Granulite of 251±21 Ma. (Restrepo et al, 1991) of the El Retiro group SE of Medellin. However, a K-Ar biotite age of 110±10 Ma. (Toussaint et al., 1978) was obtained for a migmatite rock associated with the same group. 2. A Sm/Nd garnet and whole rock age of 226±17 Ma in rocks associated to granulites, SE of Medellin, interpreted as metamorphic ages (Correa and Martins, 2001). 3. K-Ar biotite dates for the Puqui metamorphic complex, occurring north of Medellin, ranging

High northern geomagnetic field behavior and new constraints on the Gilsá event: Paleomagnetic and ⁴⁰Ar/³⁹Ar results of ∼0.5–3.1 Ma basalts from Jökuldalur, Iceland

DEFF Research Database (Denmark)

Døssing Andreasen, Arne; Muxworthy, Adrian R.; Supakulopas, Radchagrit

2016-01-01

.2–1.83 Ma, thus filling a large data gap of the high-northern stable field behavior. We obtain a median VADM of 57±3ZAm2 (VDM of 60±5Am2), which is higher than the median VADM of 16 intensity estimates from Antarctica (39±7 ZAm2) from the same period. A higher northern field is also found when using less...... strict cut-off criteria resulting in 14 field estimates from Jökuldalur, i.e. we find support for higher field strength in the northern hemisphere as compared to the southern hemisphere during the Matuyama. Finally, we deliver a revised magneto-chronostratigraphic model of Jökuldalur and conduct...... an investigation of the type sections of the so-called Gilsá normal polarity event around 1.62 Ma. Our revised model is based on 11 new 40Ar/39Ar ages. No evidence is found of the existence of the Gilsá event in Jökuldalur. Instead we find that the normal polarity intervals in the type sections can both...

Competition between electronic energy transfer and relaxation in Xe doped Ar and Ne matrices studied by photoelectron spectroscopy

International Nuclear Information System (INIS)

Schwentner, N.; Koch, E.E.

1976-01-01

Thin films of solid Ar and Ne doped with 1% Xe were excited with photons in the energy range from 10 eV to 20 eV in order to measure the energy distribution of the emitted electrons. Binding energies of th host and guest levels are deduced. When host excitons are excited, strong emission of electrons is observed indicating an efficient transfer of the host exciton energy to the Xe guest atoms. The energy of the free excitons is transferred, as can be deduced from the kinetic energy of the photoemitted electrons, rather than the energy of the bound (self-trapped) excitons which are observed in luminescence experiments. Furthermore, there is a striking difference between the Ar and the Ne matrix: In the Ne matrix a fast relaxation from the n = 2 to the n = 1 state was observed and only the energy of the n = 1 exciton is transferred even when higher excitons are excited, in contrast to Ar, where the transferred energy is higher for excitation of the n = 2 excitons than for n = 1. From these observations, time hierarchies for the competition between electronic energy transfer and relaxation are deduced. (orig.) [de

Hg-Xe exciplex formation in mixed Xe/Ar matrices: molecular dynamics and luminescence study.

Science.gov (United States)

Lozada-García, Rolando; Rojas-Lorenzo, Germán; Crépin, Claudine; Ryan, Maryanne; McCaffrey, John G

2015-03-19

Luminescence of Hg((3)P1) atoms trapped in mixed Ar/Xe matrices containing a small amount of Xe is reported. Broad emission bands, strongly red-shifted from absorption are recorded which are assigned to strong complexes formed between the excited mercury Hg* and xenon atoms. Molecular dynamics calculations are performed on simulated Xe/Ar samples doped with Hg to follow the behavior of Hg* in the mixed rare gas matrices leading to exciplex formation. The role of Xe atoms in the first solvation shell (SS1) around Hg was investigated in detail, revealing the formation of two kinds of triatomic exciplexes; namely, Xe-Hg*-Xe and Ar-Hg*-Xe. The first species exists only when two xenon atoms are present in SS1 with specific geometries allowing the formation of a linear or quasi-linear exciplex. In the other geometries, or in the presence of only one Xe in SS1, a linear Ar-Hg*-Xe exciplex is formed. The two kinds of exciplexes have different emission bands, the most red-shifted being that involving two Xe atoms, whose emission is very close to that observed in pure Xe matrices. Simulations give a direct access to the analysis of the experimental absorption, emission, and excitation spectra, together with the dynamics of exciplexes formation.

A high-precision 40Ar/39Ar age for the Nördlinger Ries impact crater, Germany, and implications for the accurate dating of terrestrial impact events

Science.gov (United States)

Schmieder, Martin; Kennedy, Trudi; Jourdan, Fred; Buchner, Elmar; Reimold, Wolf Uwe

2018-01-01

40Ar/39Ar dating of specimens of moldavite, the formation of which is linked to the Ries impact in southern Germany, with a latest-generation ARGUS VI multi-collector mass spectrometer yielded three fully concordant plateau ages with a weighted mean age of 14.808 ± 0.021 Ma (± 0.038 Ma including all external uncertainties; 2σ; MSWD = 0.40, P = 0.67). This new best-estimate age for the Nördlinger Ries is in general agreement with previous 40Ar/39Ar results for moldavites, but constitutes a significantly improved precision with respect to the formation age of the distal Ries-produced tektites. Separates of impact glass from proximal Ries ejecta (suevite glass from three different surface outcrops) and partially melted feldspar particles from impact melt rock of the SUBO 18 Enkingen drill core failed to produce meaningful ages. These glasses show evidence for excess 40Ar introduction, which may have been incurred during interaction with hydrothermal fluids. Only partially reset 40Ar/39Ar ages could be determined for the feldspathic melt separates from the Enkingen core. The new 40Ar/39Ar results for the Ries impact structure constrain the duration of crater cooling, during the prevailing hydrothermal activity, to locally at least ∼60 kyr. With respect to the dating of terrestrial impact events, this paper briefly discusses a number of potential issues and effects that may be the cause for seemingly precise, but on a kyr-scale inaccurate, impact ages.

Hybrid simulation of electron energy distributions and plasma characteristics in pulsed RF CCP sustained in Ar and SiH4/Ar discharges

Science.gov (United States)

Wang, Xi-Feng; Jia, Wen-Zhu; Song, Yuan-Hong; Zhang, Ying-Ying; Dai, Zhong-Ling; Wang, You-Nian

2017-11-01

Pulsed-discharge plasmas offer great advantages in deposition of silicon-based films due to the fact that they can suppress cluster agglomeration, moderate the energy of bombarding ions, and prolong the species' diffusion time on the substrate. In this work, a one-dimensional fluid/Monte-Carlo hybrid model is applied to study pulse modulated radio-frequency (RF) plasmas sustained in capacitively coupled Ar and SiH4/Ar discharges. First, the electron energy distributions in pulsed Ar and SiH4/Ar plasmas have been investigated and compared under identical discharge-circuit conditions. The electron energy distribution function (EEDF) in Ar discharge exhibits a familiar bi-Maxwellian shape during the power-on phase of the pulse, while a more complex (resembling a multi-Maxwellian) distribution with extra inflection points at lower energies is observed in the case of the SiH4/Ar mixture. These features become more prominent with the increasing fraction of SiH4 in the gas mixture. The difference in the shape of the EEDF (which is pronounced inside the plasma but not in the RF sheath where electron heating occurs) is mainly attributed to the electron-impact excitations of SiH4. During the power-off phase of the pulse, the EEDFs in both Ar and SiH4/Ar discharges evolve into bi-Maxwellian shapes, with shrinking high energy tails. Furthermore, the parameter of ion species in the case of SiH4/Ar discharge is strongly modulated by pulsing. For positive ions, such as SiH3+ and Si2H4+ , the particle fluxes overshoot at the beginning of the power-on interval. Meanwhile, for negative ions such as SiH2- and SiH3- , density profiles observed between the electrodes are saddle-shaped due to the repulsion by the self-bias electric field as it builds up. During the power-off phase, the wall fluxes of SiH2- and SiH3- gradually increase, leading to a significant decrease in the net surface charge density on the driven electrode. Compared with ions, the density of SiH3 is poorly modulated

40Ar/(39)Ar geochronology and paleomagnetic stratigraphy of the Lukeino and lower Chemeron Formations at Tabarin and Kapcheberek, Tugen Hills, Kenya.

Science.gov (United States)

Deino, Alan L; Tauxe, Lisa; Monaghan, Marc; Hill, Andrew

2002-01-01

(40)Ar/(39)Ar single-crystal laser-fusion dating, K-Ar dating, and paleomagnetic reversal stratigraphy have been used to determine the chronostratigraphy of the Kabarnet Trachyte, Lukeino Formation, Kaparaina Basalt Formation, and Chemeron Formation at the sites of Kapcheberek (BPRP#77) and Tabarin (BPRP#77) in the Tugen Hills, Kenya. The succession ranges in age from 6.56-3.8 Ma. The upper Lukeino Formation at Kapcherberek, including the fauna from the site BPRP#76, was deposited during chron C3r and can be constrained to the interval 5.88-5.72 Ma. The Chemeron Formation at Tabarin includes at the base an ignimbrite and associated basal air-fall tuff with a combined age of 5.31+/-0.03 Ma. Sedimentary and volcaniclastic rocks of the Chemeron Formation which unconformably overlie the ignimbrite record chrons C3n.2n through C2Ar. The combined(40)Ar/(39)Ar and paleomagnetic data constrain the age of this sequence to 4.63-3.837 Ma. The age of the Tabarin mandible fragment (KNM-TH 13150) and associated fauna at site BPRP#77 in the Chemeron Formation is 4.48-4.41 Ma, marginally older than similar early hominids from Aramis, Ethiopia. Basin subsidence appears to be defining an overall accumulation rate of about 17 cm/ka over the 2.7 Ma represented at Tabarin and Kapcheberek, despite episodes of rapid accumulation and hiatuses. Copyright 2002 Academic Press.

Recruitment of HDAC4 by transcription factor YY1 represses HOXB13 to affect cell growth in AR-negative prostate cancers

DEFF Research Database (Denmark)

Ren, Guoling; Zhang, Guocui; Dong, Zhixiong

2008-01-01

HOXB13 is a homeodomain protein implicated to play a role in growth arrest in AR (androgen receptor)-negative prostate cancer cells. Expression of HOXB13 is restricted to the AR-expressing prostate cells. In this report, we demonstrate that the HDAC inhibitor NaB (sodium butyrate) was able...... to induce cell growth arrest and to increase HOXB13 expression in AR-negative prostate cancer cells. We also show that both HDAC4 and YY1 participated in the repression of HOXB13 expression through an epigenetic mechanism involving histone acetylation modification. Specifically, co...

Nicotine induced CpG methylation of Pax6 binding motif in StAR promoter reduces the gene expression and cortisol production

International Nuclear Information System (INIS)

Wang, Tingting; Chen, Man; Liu, Lian; Cheng, Huaiyan; Yan, You-E; Feng, Ying-Hong; Wang, Hui

2011-01-01

Steroidogenic acute regulatory protein (StAR) mediates the rate-limiting step in the synthesis of steroid hormones, essential to fetal development. We have reported that the StAR expression in fetal adrenal is inhibited in a rat model of nicotine-induced intrauterine growth retardation (IUGR). Here using primary human fetal adrenal cortex (pHFAC) cells and a human fetal adrenal cell line NCI-H295A, we show that nicotine inhibits StAR expression and cortisol production in a dose- and time-dependent manner, and prolongs the inhibitory effect on cells proliferating over 5 passages after termination of nicotine treatment. Methylation detection within the StAR promoter region uncovers a single site CpG methylation at nt -377 that is sensitive to nicotine treatment. Nicotine-induced alterations in frequency of this point methylation correlates well with the levels of StAR expression, suggesting an important role of the single site in regulating StAR expression. Further studies using bioinformatics analysis and siRNA approach reveal that the single CpG site is part of the Pax6 binding motif (CGCCTGA) in the StAR promoter. The luciferase activity assays validate that Pax6 increases StAR gene expression by binding to the glucagon G3-like motif (CGCCTGA) and methylation of this site blocks Pax6 binding and thus suppresses StAR expression. These data identify a nicotine-sensitive CpG site at the Pax6 binding motif in the StAR promoter that may play a central role in regulating StAR expression. The results suggest an epigenetic mechanism that may explain how nicotine contributes to onset of adult diseases or disorders such as metabolic syndrome via fetal programming. -- Highlights: ► Nicotine-induced StAR inhibition in two human adrenal cell models. ► Nicotine-induced single CpG site methylation in StAR promoter. ► Persistent StAR inhibition and single CpG methylation after nicotine termination. ► Single CpG methylation located at Pax6 binding motif regulates StAR

Imaging the electron transfer reaction of Ne2+ with Ar using position-sensitive coincidence spectroscopy

International Nuclear Information System (INIS)

Harper, Sarah M; Hu Wanping; Price, Stephen D

2002-01-01

A new experiment, employing position-sensitive detection coupled with time-of-flight mass spectrometry, has been used to investigate the single-electron transfer reaction between Ne 2+ and Ar by detecting the resulting pairs of singly charged ions in coincidence. The experimental technique allows the determination of the individual velocity vectors of the ionic products, in the centre-of-mass frame, for each reactive event detected. The experiments show that forward scattering dominates the reactivity, although a bimodal angular distribution is apparent. In addition, the spectra show that at laboratory frame collision energies from 4-14 eV the reactivity is dominated by Ne 2+ (2p 4 , 3 P) accepting an electron from an argon atom to form the ground state of Ne + together with an Ar + ion in an excited electronic level, predominantly arising from the Ar + (3s 2 3p 4 3d) configuration. The form of this reactivity, and the differences between the reactivity observed in these experiments and those performed at higher collision energies, are well reproduced by Landau-Zener theory

Measurements of the {sup 40}Ar(n, γ){sup 41}Ar radiative-capture cross section between 0.4 and 14.8 MeV

Energy Technology Data Exchange (ETDEWEB)

Bhike, Megha, E-mail: megha@tunl.duke.edu [Department of Physics, Duke University, Durham, NC 27708 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Fallin, B.; Tornow, W. [Department of Physics, Duke University, Durham, NC 27708 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States)

2014-09-07

The {sup 40}Ar(n, γ){sup 41}Ar neutron capture cross section has been measured between 0.4 and 14.8 MeV neutron energy using the activation technique. The data are important for estimating backgrounds in argon-based neutrino and dark-matter detectors and in the neutrino-less double-beta decay search GERDA, which uses liquid argon as cooling and shielding medium. For the first time the {sup 40}Ar(n, γ){sup 41}Ar cross section has been measured for neutron energies above 1 MeV. Our results are compared to the evaluation ENDF/B-VII.1 and the calculated prediction TENDL-2013. The latter agrees very well with the present results.

75 FR 53876 - Proposed Establishment of Class E Airspace; Berryville, AR

Science.gov (United States)

2010-09-02

... Class E Airspace; Berryville, AR AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). SUMMARY: This action proposes to establish Class E airspace at Berryville, AR... SIAPs operations at Carroll County Airport, Berryville, AR. Controlled airspace is needed for the safety...

78 FR 25231 - Proposed Establishment of Class E Airspace; Colt, AR

Science.gov (United States)

2013-04-30

...-1281; Airspace Docket No. 12-ASW-13] Proposed Establishment of Class E Airspace; Colt, AR AGENCY... action proposes to establish Class E airspace at Colt, AR. Controlled airspace is necessary to...-mile radius of Delta Regional Airport, Colt, AR, to accommodate new standard instrument approach...

Reducing barriers to energy efficiency in the German higher education sector. Final report

Energy Technology Data Exchange (ETDEWEB)

Schleich, J.; Boede, U.

2000-12-01

This report describes the empirical research into barriers to energy efficiency in the German higher education (HE) sector. It is one of nine such reports in the BARRIERS project. The report contains description and analysis of six case studies of energy management in German universities. The results are analysed using the theoretical framework developed for the BARRIERS project (Sorrell et al., 2000). The report also provides brief recommendations on how these barriers to the rational use of energy (RUE) may be overcome and how energy efficiency within the sector may be improved. The results of the study for the higher education sector in Germany are summarised in this executive summary under the following headings: - Characterising the higher education sector; - Case studies of energy management in the German higher education sector; - Evidence of barriers in the German higher education sector; - The role of energy service companies in the higher education sector; - Policy implications. (orig.)

Cerebral A1 adenosine receptors (A1AR) in liver cirrhosis

International Nuclear Information System (INIS)

Boy, Christian; Meyer, Philipp T.; Kircheis, Gerald; Haussinger, Dieter; Holschbach, Marcus H.; Coenen, Heinz H.; Herzog, Hans; Elmenhorst, David; Kaiser, Hans J.; Zilles, Karl; Bauer, Andreas

2008-01-01

The cerebral mechanisms underlying hepatic encephalopathy (HE) are poorly understood. Adenosine, a neuromodulator that pre- and postsynaptically modulates neuronal excitability and release of classical neurotransmitters via A 1 adenosine receptors (A 1 AR), is likely to be involved. The present study investigates changes of cerebral A 1 AR binding in cirrhotic patients by means of positron emission tomography (PET) and [ 18 F]CPFPX, a novel selective A 1 AR antagonist. PET was performed in cirrhotic patients (n = 10) and healthy volunteers (n = 10). Quantification of in vivo receptor density was done by Logan's non-invasive graphical analysis (pons as reference region). The outcome parameter was the apparent binding potential (aBP, proportional to B max /K D ). Cortical and subcortical regions showed lower A 1 AR binding in cirrhotic patients than in controls. The aBP changes reached statistical significance vs healthy controls (p 1 AR binding may further aggravate neurotransmitter imbalance at the synaptic cleft in cirrhosis and hepatic encephalopathy. Different pathomechanisms may account for these alterations including decrease of A 1 AR density or affinity, as well as blockade of the A 1 AR by endogenous adenosine or exogenous xanthines. (orig.)

Decisive factors affecting plasma resistance and roughness formation in ArF photoresist

Energy Technology Data Exchange (ETDEWEB)

Jinnai, Butsurin; Uesugi, Takuji; Koyama, Koji; Samukawa, Seiji [Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Kato, Keisuke; Yasuda, Atsushi; Maeda, Shinichi [Yokohama Research Laboratories, Mitsubishi Rayon Co., Ltd, 10-1 Daikoku-cho, Tsurumi-ku, Yokohama 230-0053 (Japan); Momose, Hikaru, E-mail: samukawa@ifs.tohoku.ac.j [Corporate Research Laboratories, Mitsubishi Rayon Co., Ltd, 2-1 Miyuki-cho, Otake, Hiroshima 739-0693 (Japan)

2010-10-06

Low plasma resistance and roughness formation in an ArF photoresist are serious issues in plasma processes. To resolve these issues, we investigated several factors that affect the roughness formation and plasma resistance in an ArF photoresist. We used our neutral beam process to categorize the effects of species from the plasma on the ArF photoresist into physical bombardment, chemical reactions and ultraviolet/vacuum ultraviolet (UV/VUV) radiation. The UV/VUV radiation drastically increased the etching rates of the ArF photoresist films, and, in contrast, chemical reactions increased the formation of surface roughness. FTIR analysis indicated that the UV/VUV radiation preferentially dissociates C-H bonds in the ArF photoresist, rather than C=O bonds, because of the dissociation energies of the bonds. This indicated that the etching rates of the ArF photoresist are determined by the UV/VUV radiation because this radiation can break C-H bonds, which account for the majority of structures in the ArF photoresist. In contrast, FTIR analysis showed that chemical species such as radicals and ions were likely to react with C=O bonds, in particular C=O bonds in the lactone groups of the ArF photoresist, due to the structural and electronic effects of the lactone groups. As a result, the etching rates of the ArF photoresist can vary in different bond structures, leading to increased surface roughness in the ArF photoresist.

Fluorocarbon assisted atomic layer etching of SiO{sub 2} and Si using cyclic Ar/C{sub 4}F{sub 8} and Ar/CHF{sub 3} plasma

Energy Technology Data Exchange (ETDEWEB)

Metzler, Dominik; Oehrlein, Gottlieb S., E-mail: oehrlein@umd.edu [Department of Materials Science and Engineering, and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20740 (United States); Li, Chen [Department of Physics, and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20740 (United States); Engelmann, Sebastian; Bruce, Robert L.; Joseph, Eric A. [IBM T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States)

2016-01-15

The need for atomic layer etching (ALE) is steadily increasing as smaller critical dimensions and pitches are required in device patterning. A flux-control based cyclic Ar/C{sub 4}F{sub 8} ALE based on steady-state Ar plasma in conjunction with periodic, precise C{sub 4}F{sub 8} injection and synchronized plasma-based low energy Ar{sup +} ion bombardment has been established for SiO{sub 2} [Metzler et al., J. Vac. Sci. Technol. A 32, 020603 (2014)]. In this work, the cyclic process is further characterized and extended to ALE of silicon under similar process conditions. The use of CHF{sub 3} as a precursor is examined and compared to C{sub 4}F{sub 8}. CHF{sub 3} is shown to enable selective SiO{sub 2}/Si etching using a fluorocarbon (FC) film build up. Other critical process parameters investigated are the FC film thickness deposited per cycle, the ion energy, and the etch step length. Etching behavior and mechanisms are studied using in situ real time ellipsometry and x-ray photoelectron spectroscopy. Silicon ALE shows less self-limitation than silicon oxide due to higher physical sputtering rates for the maximum ion energies used in this work, ranged from 20 to 30 eV. The surface chemistry is found to contain fluorinated silicon oxide during the etching of silicon. Plasma parameters during ALE are studied using a Langmuir probe and establish the impact of precursor addition on plasma properties.

Preparation of water and ice samples for 39Ar dating by atom trap trace analysis (ATTA)

Science.gov (United States)

Schwefel, R.; Reichel, T.; Aeschbach-Hertig, W.; Wagenbach, D.

2012-04-01

Atom trap trace analysis (ATTA) is a new and promising method to measure very rare noble gas radioisotopes in the environment. The applicability of this method for the dating of very old groundwater with 81Kr has already been demonstrated [1]. Recent developments now show its feasibility also for the analysis of 39Ar [2,3], which is an ideal dating tracer for the age range between 50 and 1000 years. This range is of interest in the fields of hydro(geo)logy, oceanography, and glaciology. We present preparation (gas extraction and Ar separation) methods for groundwater and ice samples for later analysis by the ATTA technique. For groundwater, the sample size is less of a limitation than for applications in oceanography or glaciology. Large samples are furthermore needed to enable a comparison with the classical method of 39Ar detection by low-level counting. Therefore, a system was built that enables gas extraction from several thousand liters of water using membrane contactors. This system provides degassing efficiencies greater than 80 % and has successfully been tested in the field. Gas samples are further processed to separate a pure Ar fraction by a gas-chromatographic method based on Li-LSX zeolite as selective adsorber material at very low temperatures. The gas separation achieved by this system is controlled by a quadrupole mass spectrometer. It has successfully been tested and used on real samples. The separation efficiency was found to be strongly temperature dependent in the range of -118 to -130 °C. Since ATTA should enable the analysis of 39Ar on samples of less than 1 ccSTP of Ar (corresponding to about 100 ml of air, 2.5 l of water or 1 kg of ice), a method to separate Ar from small amounts of gas was developed. Titanium sponge was found to absorb 60 ccSTP of reactive gases per g of the getter material with reasonably high absorption rates at high operating temperatures (~ 800 ° C). Good separation (higher than 92 % Ar content in residual gas) was

77 FR 42430 - Establishment of Class E Airspace; West Memphis, AR

Science.gov (United States)

2012-07-19

...-0155; Airspace Docket No. 12-ASW-1] Establishment of Class E Airspace; West Memphis, AR AGENCY: Federal... at West Memphis, AR. Separation of existing Class E airspace surrounding West Memphis Municipal... the West Memphis, AR, area, creating controlled airspace at West Memphis Municipal Airport (77 FR...

76 FR 53359 - Proposed Establishment of Class E Airspace; Nashville, AR

Science.gov (United States)

2011-08-26

...-0497; Airspace Docket No. 11-ASW-4] Proposed Establishment of Class E Airspace; Nashville, AR AGENCY... action proposes to establish Class E airspace at Nashville, AR. Controlled airspace is necessary to... approach procedures at Howard County Airport, Nashville, AR. Controlled airspace is needed for the safety...

75 FR 5904 - Proposed Amendment of Class E Airspace; Magnolia, AR

Science.gov (United States)

2010-02-05

...-1179; Airspace Docket No. 09-ASW-35] Proposed Amendment of Class E Airspace; Magnolia, AR AGENCY... action proposes to amend Class E airspace at Magnolia, AR. Decommissioning of the Magnolia non-directional beacon (NDB) at Magnolia Municipal Airport, Magnolia, AR, has made this action necessary for the...

Identification of a new androgen receptor (AR) co-regulator BUD31 and related peptides to suppress wild-type and mutated AR-mediated prostate cancer growth via peptide screening and X-ray structure analysis.

Science.gov (United States)

Hsu, Cheng-Lung; Liu, Jai-Shin; Wu, Po-Long; Guan, Hong-Hsiang; Chen, Yuh-Ling; Lin, An-Chi; Ting, Huei-Ju; Pang, See-Tong; Yeh, Shauh-Der; Ma, Wen-Lung; Chen, Chung-Jung; Wu, Wen-Guey; Chang, Chawnshang

2014-12-01

Treatment with individual anti-androgens is associated with the development of hot-spot mutations in the androgen receptor (AR). Here, we found that anti-androgens-mt-ARs have similar binary structure to the 5α-dihydrotestosterone-wt-AR. Phage display revealed that these ARs bound to similar peptides, including BUD31, containing an Fxx(F/H/L/W/Y)Y motif cluster with Tyr in the +5 position. Structural analyses of the AR-LBD-BUD31 complex revealed formation of an extra hydrogen bond between the Tyr+5 residue of the peptide and the AR. Functional studies showed that BUD31-related peptides suppressed AR transactivation, interrupted AR N-C interaction, and suppressed AR-mediated cell growth. Combination of peptide screening and X-ray structure analysis may serve as a new strategy for developing anti-ARs that simultaneously suppress both wt and mutated AR function. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

The transcriptional programme of the androgen receptor (AR) in prostate cancer.

Science.gov (United States)

Lamb, Alastair D; Massie, Charlie E; Neal, David E

2014-03-01

The androgen receptor (AR) is essential for normal prostate and prostate cancer cell growth. AR transcriptional activity is almost always maintained even in hormone relapsed prostate cancer (HRPC) in the absence of normal levels of circulating testosterone. Current molecular techniques, such as chromatin-immunoprecipitation sequencing (ChIP-seq), have permitted identification of direct AR-binding sites in cell lines and human tissue with a distinct coordinate network evident in HRPC. The effectiveness of novel agents, such as abiraterone acetate (suppresses adrenal androgens) or enzalutamide (MDV3100, potent AR antagonist), in treating advanced prostate cancer underlines the on-going critical role of the AR throughout all stages of the disease. Persistent AR activity in advanced disease regulates cell cycle activity, steroid biosynthesis and anabolic metabolism in conjunction with regulatory co-factors, such as the E2F family, c-Myc and signal transducer and activator of transcription (STAT) transcription factors. Further treatment approaches must target these other factors. © 2013 The Authors. BJU International © 2013 BJU International.

AR(p) -based detrended fluctuation analysis

Science.gov (United States)

Alvarez-Ramirez, J.; Rodriguez, E.

2018-07-01

Autoregressive models are commonly used for modeling time-series from nature, economics and finance. This work explored simple autoregressive AR(p) models to remove long-term trends in detrended fluctuation analysis (DFA). Crude oil prices and bitcoin exchange rate were considered, with the former corresponding to a mature market and the latter to an emergent market. Results showed that AR(p) -based DFA performs similar to traditional DFA. However, the former DFA provides information on stability of long-term trends, which is valuable for understanding and quantifying the dynamics of complex time series from financial systems.

A Study on Tracking and Augmentation in Mobile AR for e-Leisure

Directory of Open Access Journals (Sweden)

Seong-Wook Jang

2018-01-01

Full Text Available Recently, a mobile augmented reality (AR system with AR technology that requires high performance has become popular due to the improved performance of smartphones. In particular, mobile AR that directly interacts with outdoor environments has been in development because of increasing interest in e-leisure due to improvements in living standards. Therefore, this paper aims to study tracking and augmentation in mobile AR for e-leisure. We analyzed the performance of human body tracking application implemented in a mobile system (smartphone using three methods (marker-based, markerless, and sensor-based for the feasibility examination of human body tracking in mobile AR. Furthermore, game information augmentation was examined through the implementation of mobile AR using two methods (marker- and sensor-based.

75 FR 29656 - Amendment of Class E Airspace; Mountain View, AR

Science.gov (United States)

2010-05-27

...-1181; Airspace Docket No. 09-ASW-36] Amendment of Class E Airspace; Mountain View, AR AGENCY: Federal... Mountain View, AR. Decommissioning of the Wilcox non-directional beacon (NDB) at Mountain View Wilcox Memorial Field Airport, Mountain View, AR, has made this action necessary to enhance the safety and...

75 FR 6594 - Proposed Amendment of Class E Airspace; Osceola, AR

Science.gov (United States)

2010-02-10

...-1183; Airspace Docket No. 09-ASW-38] Proposed Amendment of Class E Airspace; Osceola, AR AGENCY... action proposes to amend Class E airspace at Osceola, AR. Decommissioning of the Osceola non-directional beacon (NDB) at Osceola Municipal Airport, Osceola, AR, has made this action necessary for the safety and...

K-Ar age of bronzite-andesite from Choshi, Chiba Prefecture, Japan

International Nuclear Information System (INIS)

Tatsumi, Yoshiyuki; Ishizaka, Kyoichi

1979-01-01

The authors have forwarded the study on the activity period of Setouchi volcanic rocks and the research on Sanukitoid which characterizes it. It was already mentioned that the activity period of Setouchi volcanic rocks is only the middle period of Mid-cainozoic era, and that Setouchi volcanic rocks can be treated as one rock region. In this paper, the K-Ar age of bronzite-andesite in Choshi, Chiba Prefecture, is reported, which the authors think as the eastern end of Setouchi volcanic rock region. The outline of the geological features in the vicinity of Choshi is explained. The rock samples for the measurement were collected in May, 1978, in the reconstruction site of the fishing port. The rock samples were fresh, and the effects of degeneration, wathering and others were not observed. The K-Ar age of these bronzite-andesite was determined by Teledyne Isotopes Co. in commission. The determination of K and Ar was carried out on all rock samples twice respectively. The isotopic age of the bronzite-andesite in Choshi was 11.8 +- 0.6 m.y., and it was produced by the volcanic activity in the middle period of Mid-cainozoic era, same as the volcanic rocks of Setouchi. It is considered that the eastern end of Setouchi volcanic rock region is Choshi according to the results of chemical properties and isotopic age. (Kako, I.)

Alpine orogenic evolution from subduction to collisional thermal overprint: The 40Ar/39Ar age constraints from the Valaisan Ocean, central Alps

DEFF Research Database (Denmark)

Wiederkehr, Michael; Sudo, Masafumi; Bousquet, Romain

2009-01-01

in general. The timing of high-pressure metamorphism, subsequent retrogression and following Barrow-type overprint was studied by 40Ar/39Ar dating of biotite and several white mica generations that are well characterized in terms of mineral chemistry, texture and associated mineral assemblages. Four distinct...

Ramon Llull's Ars Magna

DEFF Research Database (Denmark)

Jensen, Thessa

2018-01-01

The Ars Magna of Ramon Llull must be seen as one of the first attempts to formalise language, thought processes, and creating a basis for rational discussions. It consists of so-called principles, concepts, which are defined and combined through the use of four main figures. Llull's contribution...

ARS-Media for Excel

Science.gov (United States)

ARS-Media for Excel is an ion solution calculator that uses Microsoft Excel to generate recipes of salts for complex ion mixtures specified by the user. Generating salt combinations (recipes) that result in pre-specified target ion values is a linear programming problem. Thus, the recipes are genera...

Investigation of the energy levels of 38AR

International Nuclear Information System (INIS)

Waanders, F.B.

1975-07-01

In this project information on the energy levels of 38 Ar was obtained by means of the (p,γ) reaction. The 1,1 MeV Cockroft-Walton accelerator of the Potchefstroom University for CHE was used to produce the proton beam while a 80 cm 3 Ge(Li) detector was used to detect the gamma-rays. Precise gamma-branchings were determined for 50 bound levels, of which four have not previously been determined. These branchings were obtained from the 28 resonances studied in the 37 Cl(p,γ) 38 Ar reaction. The resonance with a proton energy of (592 plus minus 3) keV was not detected previously. The resonance energies, Q-value and energies of the bound levels used in this project were taken from the study done by Alderliesten. The mean lifetimes of a few bound levels of 38 Ar were measured by means of the doppler shift attenuation method. The results concerning the bound states and mean lifetimes are in good agreement with previous experiments. Limitations on the spin and parities of 19 (p,γ) resonances have been set by means of Weisskopf estimates. Only those cases for which the spin could be limited to two values are discussed in the text. A summary of experimental data obtained on 38 Ar is compared with the results from shellmodel calculations done by various workers. A short discussion on the analogue states in 38 Ar is also given [af

41Ar-concentration measurements at the Finnish TRIGA Mark II

International Nuclear Information System (INIS)

Tamminen, A.

1970-01-01

41 Ar-concentrations in the reactor hall and in the Ar-ventilation duct of FiR-1 (IRIGA Mark II, 250 kW) have been measured during normal operation conditions. Additional measurements have been performed varying Ar-ventilation and hall ventilation flow. A γ- and background compensated thin window proportional detector and a β-Geiger detector for 41 Ar-measurements are described. The hall concentration has also been estimated from background measurements with an unshielded Ge(Li)-detector. The saturation concentration in the reactor hall with and without the hall ventilation is about 1 x 10 -7 μCi/cm 3 and 3 x 10 -7 μCi/cm 3 , respectively. (author)

40Ar/ 39Ar dating of Late Permian evaporites, southeastern New Mexico, USA

Science.gov (United States)

Renne, Paul R.; Sharp, Warren D.; Montañez, Isabel P.; Becker, Tim A.; Zierenberg, Robert A.

2001-12-01

40Ar/ 39Ar dating of the potassium-magnesium sulfate mineral langbeinite from Permian evaporites of the Salado formation near Carlsbad, New Mexico, provides quantitative evidence that some salts in these deposits have not recrystallized for 251 Myr since deposition. Survival of Permian salts supports the possibility that Bacillus bacteria recovered from nearby halite was isolated in a closed system and represents a sample of uncontaminated Permian life. Local recrystallization of langbeinite and other nearby minerals is also indicated by the dating, suggesting both the need and the opportunity to document closed system behavior more rigorously. The shoaling and desiccation event recorded by the Salado formation began at least 1 Myr before the Permian-Triassic boundary. Temporal correlation of the Salado with the Zechstein evaporites of north-central Europe supports previously inferred regression models for the origin of these deposits. Significant paleoenvironmental change at the Permian-Triassic boundary thus occurred on a time scale more protracted than that implied by geologically instantaneous events such as bolide impacts.

75 FR 43884 - Proposed Amendment of Class E Airspace; Searcy, AR

Science.gov (United States)

2010-07-27

...-1182; Airspace Docket No. 09-ASW-37] Proposed Amendment of Class E Airspace; Searcy, AR AGENCY: Federal... proposes to amend Class E airspace at Searcy, AR. Decommissioning of the Searcy non-directional beacon (NDB) at Searcy Municipal Airport, Searcy, AR, has made this action necessary for the safety and management...

Geochronological 40Ar/39Ar data on the submarine fault-scarps in the Sardinia channel (western mediterranean)

International Nuclear Information System (INIS)

Bouillin, J.P.; Tricart, P.; Mascle, G.; Monie, P.; Rolfo, F.; Torelli, L.

1999-01-01

Granite and gneiss have been sampled on the submarine fault scarps of the Sardinia Channel and have been dated using the 40 Ar/ 39 Ar method. The majority of rocks partially preserve Hercynian ages. Some of them display Lower Cretaceous ages. In addition, Upper Eocene-Oligocene argon resetting is recorded only in rocks from the southeast sector of the Channel. We thus propose that the basement of the Sardinia Channel occupied a shallow position within the stack of the Alpine tectonic units, behind the more deformed front of the internal zones of the Maghrebide Chain. (authors)

K-Ar age of molybdenum mineralization in the east-central Kitakami Mountains, northern Honshu, Japan

International Nuclear Information System (INIS)

Ishihara, Shunso; Shibata, Ken; Uchiumi, Shigeru

1989-01-01

Three K-Ar ages were determined on rocks and minerals from the mineralized areas in the east-central part of the Kitakami Cretaceous granitic terrain, where a Paleogene mineralization age was reported recently on molybdenite by the Re-Os method. The present result showed an early Cretaceous age of 114±4 Ma for the same molybdenite deposit. A rather large discrepancy was found between the Re-Os ages for molybdenite and the K-Ar and Rb-Sr ages for silicate minerals from the same ore deposits of Mesozoic-Cenozoic ages in the Circum-Pacific region, indicating that the Re-Os method needs further examination. (author)

40Ar/39Ar dating and zircon chronochemistry for the Izu-Bonin rear arc, IODP site U1437

Science.gov (United States)

Schmitt, A. K.; Konrad, K.; Andrews, G. D.; Horie, K.; Brown, S. R.; Koppers, A. A. P.; Busby, C.; Tamura, Y.

2016-12-01

The scientific objective of IODP Expedition 350 drilling at Site U1437 (31°47.390'N, 139°01.580'E) was to reveal the "missing half of the subduction factory": the rear arc of a long-lived intraoceanic subduction zone. Site U1437 lies in a 50 km long and 20 km wide volcano-bounded basin, 90 km west of the Izu arc front, and is the only IODP site drilled in the rear arc. The Izu rear arc is dominated by Miocene basaltic to dacitic seamount chains, which strike at a high angle to the arc front. Radiometric dating targeted a single igneous unit (1390 mbsf), and fine to coarse volcaniclastic units for which we present zircon and 40Ar/39Ar (hornblende, plagioclase, and groundmass) age determinations. All zircons analyzed as grain separates were screened for contamination from drill-mud (Andrews et al., 2016) by analyzing trace elements and, where material was available, O and Hf isotope compositions. Igneous Unit 1 is a rhyolite sheet and yielded concordant in-situ and crystal separate U-Pb zircon ages (13.7±0.3 Ma; MSWD = 1.3; n = 40 spots), whereas the 40Ar/39Ar hornblende plateau age (12.9±0.3; MSWD = 1.1; n = 9 steps) is slightly younger, possibly reflecting pre-eruptive zircon crystallization, or alteration of hornblende. U-Pb zircon and 40Ar/39Ar plateau ages from samples above igneous Unit 1 are concordant with biostratigraphic and paleomagnetic ages (available to 1300 mbsf), but plagioclase and groundmass samples below 1300 m become younger with depth, hinting at post-depositional alteration. A single zircon from 1600 mbsf yielded a U-Pb age of 15.4±1.8 Ma; its trace element composition resembles other igneous zircons from U1437, and is tentatively interpreted as a Middle Miocene age for the lowermost lithostratigraphic unit VII. Oxygen and Hf isotopic values of igneous zircon indicate mantle origins, with some influence of assimilation of hydrothermally altered oceanic crust evident in sub-mantle oxygen isotopic compositions. Lessons from site U1437 are

RBS-channeling study of radiation damage in Ar{sup +} implanted CuInSe{sub 2} crystals

Energy Technology Data Exchange (ETDEWEB)

Yakushev, Michael V., E-mail: michael.yakushev@strath.ac.uk [Department of Physics, SUPA, Strathclyde University, Glasgow G4 0NG (United Kingdom); Ural Federal University, Ekaterinburg 620002 (Russian Federation); Institute of Solid State Chemistry of the Urals Branch of RAS, Ekaterinburg 620990 (Russian Federation); Volkov, Vladimir A. [Ural Federal University, Ekaterinburg 620002 (Russian Federation); Mursakulov, Niyazi N.; Sabzaliyeva, Chimnaz E. [Institute of Physics, National Academy of Sciences of Azerbaijan, H.Cavid ave., 33, AZ-1143 Baku (Azerbaijan); Martin, Robert W. [Department of Physics, SUPA, Strathclyde University, Glasgow G4 0NG (United Kingdom)

2016-09-15

Chalcopyrite solar cells are reported to have a high tolerance to irradiation by high energy electrons or ions, but the origin of this is not well understood. This work studies the evolution of damage in Ar{sup +}-bombarded CuInSe{sub 2} single crystal using Rutherford backscattering/channeling analysis. Ar{sup +} ions of 30 keV were implanted with doses in the range from 10{sup 12} to 3 × 10{sup 16} cm{sup −2} at room temperature. Implantation was found to create two layers of damage: (1) on the surface, caused by preferential sputtering of Se and Cu atoms; (2) at the layer of implanted Ar, possibly consisting of stacking faults and dislocation loops. The damage in the second layer was estimated to be less than 2% of the theoretical prediction suggesting efficient healing of primary implantation defects.

Spectra of Th/Ar and U/Ne hollow cathode lamps for spectrograph calibration

Science.gov (United States)

Nave, Gillian; Shlosberg, Ariel; Kerber, Florian; Den Hartog, Elizabeth; Neureiter, Bianca

2018-01-01

Low-current Th/Ar hollow cathode lamps have long been used for calibration of astronomical spectrographs on ground-based telescopes. Thorium is an attractive element for calibration as it has a single isotope, has narrow spectral lines, and has a dense spectrum covering the whole of the visible region. However, the high density of the spectrum that makes it attractive for calibrating high-resolution spectrographs is a detriment for lower resolution spectrographs and this is not obvious by examination of existing linelists. In addition, recent changes in regulations regarding the handling of thorium have led to a degradation in the quality of Th/Ar calibration lamps, with contamination by molecular ThO lines that are strong enough to obscure the calibration lines of interest.We are pursuing two approaches to these problems. First, we have expanded and improved the NIST Standard Reference Database 161, "Spectrum of Th-Ar Hollow Cathode Lamps" to cover the region 272 nm to 5500 nm. Spectra of hollow cathode lamps at up to 3 different currents can now be displayed simultaneously. Interactive zooming and the ability to convolve any of the spectra with a Gaussian or uploaded instrument profile enable the user to see immediately what the spectrum would look like at the particular resolution of their spectrograph. Second, we have measured the spectrum of a recent, contaminated Th/Ar hollow cathode lamp using a high-resolution Echelle spectrograph (Madison Wisconsin) at a resolving power (R~ 250,000). This significantly exceeds the resolving power of most astronomical spectrographs and resolves many of the molecular lines of ThO. With these spectra we are measuring and calibrating the positions of these molecular lines in order to make them suitable for spectrograph calibration.In the near infrared region, U/Ne hollow cathode lamps give a higher density of calibration lines than Th/Ar lamps and will be implemented on the upgraded CRIRES+ spectrograph on ESO’s Very Large

Ars ornata / Kadri Mälk

Index Scriptorium Estoniae

Mälk, Kadri, 1958-

1998-01-01

V rahvusvaheline ehtekunsti konverents 'Ars ornata Europeana' juuni lõpus Stockholmis. New Yorgis elava kuraatori Charon Kranseni ja prantsuse ehtekunstniku Christophe Burger' juhitud vestlusringidest. 1997. a. Pariisis loodud International Craft Design Association'ist (ICDA).

İMDAT AVŞAR AND HIS STORYTELLING İMDAT AVŞAR VE HİKÂYECİLİĞİ

Directory of Open Access Journals (Sweden)

Zehra YAZBAHAR

2011-01-01

Full Text Available With his stories in his first book which is Steppe Which Fade To Crocuses he published in 2010, Imdat Avşar reflects our society and our traditional values. In this study which is primarily composed of two major parts, after giving brief information about Imdat Avşar in the first section, the art of storytelling will be part in the second section and the stories in the mentioned book are gotten the grips with narrator, viewpoint, content, characters, language and style. İmdat Avşar, 2010 yılında yayımladığı Çiğdemleri Solan Bozkır isimli ilk hikâye kitabındaki hikâyeleri ile aynasını Türk toplumuna ve onun geleneksel değerlerine tutar. Esas itibariyle iki ana bölümden oluşan bu çalışmada, ilk bölümde İmdat Avşar hakkında kısa bir bilgi verildikten sonra ikinci bölümde hikâyeciliğine geçilecek ve sözü edilen kitabındaki hikâyeleri, anlatıcı ve bakış açısı, içerik ve kişiler kadrosu, dil ve üslûp başlıkları altında ele alınacaktır.

Nicotine induced CpG methylation of Pax6 binding motif in StAR promoter reduces the gene expression and cortisol production

Energy Technology Data Exchange (ETDEWEB)

Wang, Tingting [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Chen, Man; Liu, Lian [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Cheng, Huaiyan [Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Yan, You-E [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Feng, Ying-Hong, E-mail: yhfeng@usuhs.edu [Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China)

2011-12-15

Steroidogenic acute regulatory protein (StAR) mediates the rate-limiting step in the synthesis of steroid hormones, essential to fetal development. We have reported that the StAR expression in fetal adrenal is inhibited in a rat model of nicotine-induced intrauterine growth retardation (IUGR). Here using primary human fetal adrenal cortex (pHFAC) cells and a human fetal adrenal cell line NCI-H295A, we show that nicotine inhibits StAR expression and cortisol production in a dose- and time-dependent manner, and prolongs the inhibitory effect on cells proliferating over 5 passages after termination of nicotine treatment. Methylation detection within the StAR promoter region uncovers a single site CpG methylation at nt -377 that is sensitive to nicotine treatment. Nicotine-induced alterations in frequency of this point methylation correlates well with the levels of StAR expression, suggesting an important role of the single site in regulating StAR expression. Further studies using bioinformatics analysis and siRNA approach reveal that the single CpG site is part of the Pax6 binding motif (CGCCTGA) in the StAR promoter. The luciferase activity assays validate that Pax6 increases StAR gene expression by binding to the glucagon G3-like motif (CGCCTGA) and methylation of this site blocks Pax6 binding and thus suppresses StAR expression. These data identify a nicotine-sensitive CpG site at the Pax6 binding motif in the StAR promoter that may play a central role in regulating StAR expression. The results suggest an epigenetic mechanism that may explain how nicotine contributes to onset of adult diseases or disorders such as metabolic syndrome via fetal programming. -- Highlights: Black-Right-Pointing-Pointer Nicotine-induced StAR inhibition in two human adrenal cell models. Black-Right-Pointing-Pointer Nicotine-induced single CpG site methylation in StAR promoter. Black-Right-Pointing-Pointer Persistent StAR inhibition and single CpG methylation after nicotine termination

Electron-impact excitation rate-coefficients and polarization of subsequent emission for Ar"+ ion

International Nuclear Information System (INIS)

Dipti; Srivastava, Rajesh

2016-01-01

Electron impact excitation in Ar"+ ions has been studied by using fully relativistic distorted wave theory. Calculations are performed to obtain the excitation cross-sections and rate-coefficients for the transitions from the ground state 3p"5 (J=3/2) to fine-structure levels of excited states 3p"44s, 3p"44p, 3p"45s, 3p"45p, 3p"43d and 3p"44d. Polarization of the radiation following the excitation has been calculated using the obtained magnetic sub-level cross-sections. Comparison of the present rate-coefficients is also done with the previously reported theoretical results for some unresolved fine structure transitions. - Highlights: • Fully relativistic distorted wave theory has been used to study the excitation of fine-structure states of Ar"+. • We have calculated electron-impact excitation cross-sections for the wide range of incident electron energies. • Electron impact excitation rate-coefficients are calculated as a function of electron temperature. • Polarization of photons emitted following the decay of the excited fine-structure states are also reported.

$\\beta$ decay of $^{47}$Ar

CERN Document Server

Weissman, L; Bergmann, U C; Brown, B A; Catherall, R; Cederkäll, J; Dillmann, I; Hallmann, O; Fraile-Prieto, L M; Franchoo, S; Gaudefroy, L; Köster, U; Kratz, K L; Pfeiffer, B; Sorlin, O; 10.1103/PhysRevC.70.024304

2004-01-01

Information on beta -decay properties of neutron-rich /sup 47/Ar was obtained at the ISOLDE facility at CERN using isobaric selectivity. This was achieved by a combination of a plasma-ion source with a cooled transfer line and subsequent mass separation. A doubly charged beam was used in order to improve the signal-to-background ratio associated with multi-charged noble gas fission products. The identification of the /sup 47/Ar gamma -ray transitions was performed by comparing the spectra obtained from direct proton bombardment of the target and of the neutron converter. New excited levels in the daughter /sup 47/K nucleus corresponding to the negative-parity states were observed. The obtained data are compared to the result of large-scale shell model calculations and quasiparticle random-phase approximation predictions. (29 refs).

C5a and C5aR are elevated in joints of rheumatoid and psoriatic arthritis patients, and C5aR blockade attenuates leukocyte migration to synovial fluid

DEFF Research Database (Denmark)

Hornum, Lars; Hansen, Anker Jon; Tornehave, Ditte

2017-01-01

synovial fluid was significantly inhibited by anti-C5aR. The data support that the C5a-C5aR axis may be driving the infiltration of inflammatory cells into the synovial fluid and synovium in both rheumatoid and psoriatic arthritis, and suggest that C5a or C5aR may be a promising treatment target in both...... a Boyden chamber. Appropriate statistical tests were applied for comparisons. C5aR+ cells were detected in most rheumatoid arthritis, in all psoriatic arthritis, but not in non-inflammatory control synovia. C5aR+ cells were primarily neutrophils and macrophages. C5aR+ macrophages were mainly found...

K/Ar dating of diagenetic illites

International Nuclear Information System (INIS)

Mizusaki, A.M.P.; Anjos, S.M.C. dos; Costa, M.G.F. da; Silva, O.B. da; Kawashita, K.

1990-01-01

Ascertaining the potassium/argon (K/Ar) age of diagenetic illites yields important information for hydrocarbon exploration since the growth of this mineral in the pores of sandstone reservoir and oil migration are interlinked events in the diagenetic evolution of rocks. Illite growth ceases as soon as hydrocarbons completely fill in rock pores, displacing interstitial water. By providing an estimate of the period when the illite formed, K/Ar dating can indirectly tells us when hydrocarbons entered the reservoir. Samples of oil-saturated sandstones collected from Carboniferous reservoirs of the Solimoes Basin reveal a diagenetic evolution consisting predominantly of quartz, calcite, and illite overgrowths. In the present study, illite was mechanically separated by repeating a series of ultrasonic baths and ultrasonic probes followed by high-speed centrifuging. Resultant fractions were analyzed by X-ray diffractometry to measure the illite content of each sample. The separated illite material was found to be composed of illite and ordered mixed layer illite-smectite with 80% illite layers. Separated fractions were dated radiometrically by the K/Ar method. Preliminary results indicate an average age of some 200 m.y., which marks the end of the diagenetic development of the illites of this area. (author)

Influence of higher order modes on angled-facet amplifiers

DEFF Research Database (Denmark)

Wang, Z.; Mikkelsen, B.; Stubkjær, Kristian

1991-01-01

The influence of the first-order mode on the residual reflectivity of angled-facet amplifiers is analyzed. For a 7 degrees angled-facet ridge waveguide amplifier with a single-layer antireflective (AR) coating, a gain ripple lower than 1-dB at 25-dB gain can be obtained independent...... of the polarization, even in the presence of a first-order mode with a 15-dB gain. The tolerances for the thickness and refractive index of the AR coating are reduced by a factor of three compared to operation in the fundamental mode only. The influence of the higher order mode can virtually be suppressed...

40Ar/39Ar dating and paleo-magnetism of traps from Ethiopia, Deccan and Siberia

International Nuclear Information System (INIS)

Hofmann, C.

1997-01-01

Recent studies have shown that major flood basalt provinces have been emplaced as short events (∼ 1 Myr), more or less synchronous with climatic crises and mass extinctions. We present new geochronologic ( 40 Ar/ 39 Ar) and magneto-stratigraphic results for the Ethiopian traps, one of the last remaining flood basalts for which little of such data were available. The ages obtained in a 2000 m thick section are indistinguishable. Moreover, magneto-stratigraphy reveals a simple 3-chron reverse-normal-reverse sequence. Although magnetic chrons cannot be yet unambiguously identified, there is more likelihood for the normal sub-chron in the main basaltic pile to correspond to 11N, supporting a brief duration (less than 1.5 Ma). The Ethiopian traps erupted near 30 Ma at or near the time of the cold and dry climate, major Antarctic ice sheet advance, and the largest sea-level drop in the Tertiary. Bhandari et al. (GRL, 1995) have discovered inter-traps sediments with a triple iridium anomaly in a series of seven basaltic lava flows in the Kutch area of the North Western Deccan traps of India. Plagioclases from three flows above the iridium bearing sediments yield 39 Ar/ 40 Ar plateau ages near 65.0 Ma: these flows have unambiguously reversed magnetic polarity interpreted as chron 29R. As a preliminary summary, evidence of the KTB asteroid impact is confirmed in the Deccan traps, showing that they are coeval events in a general sense (in a Ma long window) though clearly with vastly different time constants. This is compatible with paleontologic evidence of two scales of extinctions, one quasi-instantaneous and the other on the order of 10 5 to 10 6 yrs. Clearly, the impact cannot have caused trap eruptions. On the other hand, the exact age and significance of the lower flows more altered remains to be analyzed further as they pertained to the much debated question of duration of Deccan trap volcanism. (author)

Ar-41 measurements and nuclear emergency preparedness

International Nuclear Information System (INIS)

Kunst, J.J.; Rodriguez, M.; Ugarte, R.; Vigile, R.S.; Boutet, L.I.; Jordan, O.D.; Hernandez, D.G.

2010-01-01

During the early phase of an emergency is necessary to confirm the release of radioactivity predictions made by the operator of the nuclear plant. In this context, it has begun measuring Ar-41 in the vicinity of a research reactor. Since the Ar-41 is produced in the reactor, it has been studied as a good way to validate the air dispersion model used in nuclear emergencies and to develop a method to improve the characterization of the release. For this latter purpose a pilot experiment was conducted to determine computational and experimental methods, the flux of 1.29 MeV of Ar-41 and compared to evaluate the accuracy of the assessments made. This paper describes meteorological forecasting systems used in the experiment, the estimate of the stability class and the concentration of nuclides using a calculation code developed by the ARN, as well as the methodology and equipment used for measurement in the field. (authors) [es

Collisional excitation of ArH+ by hydrogen atoms

Science.gov (United States)

Dagdigian, Paul J.

2018-06-01

The rotational excitation of the 36ArH+ ion in collisions with hydrogen atoms is investigated in this work. The potential energy surface (PES) describing the 36ArH+-H interaction, with the ion bond length r fixed at the average of r over the radial v = 0 vibrational state distribution, was obtained with a coupled cluster method that included single, double, and (perturbatively) triple excitations [RCCSD(T)]. A deep minimum (De = 3135 cm-1) in the PES was found in linear H-ArH+ geometry at an ion-atom separation Re = 4.80a0. Energy-dependent cross-sections and rate coefficients as a function of temperature for this collision pair were computed in close-coupling (CC) calculations. Since the PES possesses a deep well, this is a good system to test the performance of the quantum statistical (QS) method developed by Manolopoulos and co-workers as a more efficient method to compute the cross-sections. Good agreement was found between rate coefficients obtained by the CC and QS methods at several temperatures. In a simple application, the excitation of ArH+ is simulated for conditions under which this ion is observed in absorption.

The Educational Values of Athiyyah ar-Rahman Book

Directory of Open Access Journals (Sweden)

Maya Yunita

2018-04-01

Full Text Available Athiyyah ar-Rahman is an influential book which written by Muhammad Azhari al-Palembani ibn Abdullah ibn Ahmad or also known as Kemas Azhari (1811-1874. The book was written in 1842 and until today is learned by Islamic community in Palembang. This article tries to elucidate the values of Athiyyah ar-Rahman book from education perspectives. The discourse-historical approach of Reisigl and Wodak (2008 is used to analyze the book. The findings show that Athiyyah ar-Rahman describes six pillars of Islam. The six pillars of Islam are framing three dimensions, including personal dimension, social dimension, and transformative dimension. The personal dimension relates to the core of the education to construct the self of student. The social dimension relates to the visions for harmonizing among humans and between humans and nature. Meanwhile, the transformational dimension relates to the effect of education to solve the problems in human life as well as transform the society. Based on the analysis, the educational values of Athiyyah ar-Rahman could be summarized as follows: religiosity, spirituality, morality, solidarity, tolerance, environmentalism, pragmatism and transformational.

Audit, Control and Monitoring Design Patterns (ACMDP for Autonomous Robust Systems (ARS

Directory of Open Access Journals (Sweden)

C. Trad

2008-11-01

Full Text Available This paper proposes the Audit, Control and Monitoring Design Patterns (ACMDP for building Autonomous and Robust Systems (ARS such as Mobile Robot Systems (MRS. These patterns are also applicable to other Mission Critical and Complex Systems (MCCS. This paper presents a proposal which will help ARS project managers and engineers design, build and estimate the probability that an ARS will succeed or fail. Furthermore, this proposal offers the possibility to ARS problems with the help of audit, monitoring and controlling components, adjust the project management pathways, and define the problem sources as well as their possible solutions, in order to deliver an ARS or an MRS.

Crude oil He and Ar isotopic characteristics and their geochemical significance: an example from the Gangxi oil field in the Huanghua depression

Directory of Open Access Journals (Sweden)

S. Chenpeng

2005-06-01

Full Text Available Sampled from the Gangxi oil field in the Huanghua depression, Bohaiwan Basin, the crude oil He and Ar isotopic compositions and their geochemical significance were investigated. The result shows that i the 3He/4He values of the six oil samples free from air contamination indicate a mantle helium contribution ranging between 13.9% and 32.8% and averaging 24.1%, which means that the Gangxi oil field once had a tectonic background of the mantle-derived helium input and higher geothermal flow with an average of 75.0 mWm-2; ii deduced from the 40Ar/36Ar aging effect the Gangxi oil should be derived from the Tertiary; iii water injection is the main reason for the air contamination for the Gangxi oil noble gases and the relations between 3He/4He and 4He/20Ne as well as 40Ar/36Ar and 4He/20Ne are of an applicative potential in estimating the water injection effect and the connectivity of producing formations. The search for the crude oil He and Ar isotopes provides a new approach to inferring natural gas and oil sources, tectonic backgrounds, geothermal flow and water injection effect.

Episodic Holocene eruption of the Salton Buttes rhyolites, California, from paleomagnetic, U-Th, and Ar/Ar dating

Science.gov (United States)

Wright, Heather M.; Vazquez, Jorge A.; Champion, Duane E.; Calvert, Andrew T.; Mangan, Margaret T.; Stelten, Mark E.; Cooper, Kari M.; Herzig, Charles; Schriener Jr., Alexander

2015-01-01

In the Salton Trough, CA, five rhyolite domes form the Salton Buttes: Mullet Island, Obsidian Butte, Rock Hill, North and South Red Hill, from oldest to youngest. Results presented here include 40Ar/39Ar anorthoclase ages, 238U-230Th zircon crystallization ages, and comparison of remanent paleomagnetic directions with the secular variation curve, which indicate that all domes are Holocene. 238U-230Th zircon crystallization ages are more precise than but within uncertainty of 40Ar/39Ar anorthoclase ages, suggesting that zircon crystallization proceeded until shortly before eruption in all cases except one. Remanent paleomagnetic directions require three eruption periods: (1) Mullet Island, (2) Obsidian Butte, and (3) Rock Hill, North Red Hill, and South Red Hill. Borehole cuttings logs document up to two shallow tephra layers. North and South Red Hills likely erupted within 100 years of each other, with a combined 238U-230Th zircon isochron age of: 2.83 ± 0.60 ka (2 sigma); paleomagnetic evidence suggests this age predates eruption by hundreds of years (1800 cal BP). Rock Hill erupted closely in time to these eruptions. The Obsidian Butte 238U-230Th isochron age (2.86 ± 0.96 ka) is nearly identical to the combined Red Hill age, but its Virtual Geomagnetic Pole position suggests a slightly older age. The age of aphyric Mullet Island dome is the least well constrained: zircon crystals are resorbed and the paleomagnetic direction is most distinct; possible Mullet Island ages include ca. 2300, 5900, 6900, and 7700 cal BP. Our results constrain the duration of Salton Buttes volcanism to between ca. 5900 and 500 years.

Substituent effect in spin-crossover behavior of iron(II)-Ar-pybox complexes (Ar-pybox = 4-aryl-2,6-bis(oxazolin-2-yl)pyridine)

Science.gov (United States)

Kimura, Akifumi; Ishida, Takayuki

2018-01-01

Spin-crossover (SCO) is a reversible transition between low-spin (LS) and high-spin (HS) states by external stimuli like heat. The SCO behavior of [Fe(Ar-pybox)2](ClO4)2 was investigated, where Ar-pybox stands for 4-aryl-2,6-bis(oxazolin-2-yl)pyridine with Ar = 4-pyridyl (4Py), 3-thienyl (3Th), and phenyl (Ph). They were characterized by means of single-crystal X-ray diffraction study, being consistent with the results of the magnetic measurements. The SCO temperatures (T1/2) in the polycrystalline state were determined to be 360 and 230 K for Ar = 4Py and Ph, respectively. The 3Th derivative possessed a HS state in all the temperature range. The solution susceptometry was also performed to purge intermolecular interaction and rigid crystal lattice effects, affording T1/2 = 310, 240, and 240 K for Ar = 4Py, 3Th, and Ph, respectively, in acetone. The substituent effect analysis using the Hammett substituent constant (σp) clarified that electron-withdrawing groups raise T1/2. A plausible model describing the substituent effect on T1/2 is proposed based on d-π interaction. The present result is regarded as a successful example of crystal field engineering.

The AR Sandbox: Augmented Reality in Geoscience Education

Science.gov (United States)

Kreylos, O.; Kellogg, L. H.; Reed, S.; Hsi, S.; Yikilmaz, M. B.; Schladow, G.; Segale, H.; Chan, L.

2016-12-01

The AR Sandbox is a combination of a physical box full of sand, a 3D (depth) camera such as a Microsoft Kinect, a data projector, and a computer running open-source software, creating a responsive and interactive system to teach geoscience concepts in formal or informal contexts. As one or more users shape the sand surface to create planes, hills, or valleys, the 3D camera scans the surface in real-time, the software creates a dynamic topographic map including elevation color maps and contour lines, and the projector projects that map back onto the sand surface such that real and projected features match exactly. In addition, users can add virtual water to the sandbox, which realistically flows over the real surface driven by a real-time fluid flow simulation. The AR Sandbox can teach basic geographic and hydrologic skills and concepts such as reading topographic maps, interpreting contour lines, formation of watersheds, flooding, or surface wave propagation in a hands-on and explorative manner. AR Sandbox installations in more than 150 institutions have shown high audience engagement and long dwell times of often 20 minutes and more. In a more formal context, the AR Sandbox can be used in field trip preparation, and can teach advanced geoscience skills such as extrapolating 3D sub-surface shapes from surface expression, via advanced software features such as the ability to load digital models of real landscapes and guiding users towards recreating them in the sandbox. Blueprints, installation instructions, and the open-source AR Sandbox software package are available at http://arsandbox.org .

Novel galeterone analogs act independently of AR and AR-V7 for the activation of the unfolded protein response and induction of apoptosis in the CWR22Rv1 prostate cancer cell model.

Science.gov (United States)

McCarty, David J; Huang, Weiliang; Kane, Maureen A; Purushottamachar, Puranik; Gediya, Lalji K; Njar, Vincent C O

2017-10-24

The androgen receptor (AR) has long been the primary target for the treatment of prostate cancer (PC). Despite continuous efforts to block AR activity through ligand depletion, AR antagonism, AR depletion and combinations thereof, advanced PC tumors remain resilient. Herein, we evaluate two galeterone analogs, VNPT-178 and VNLG-74A, in PC cell models of diverse androgen and AR dependence attempting to delineate their mechanisms of action and potential clinical utility. Employing basic biochemical techniques, we determined that both analogs have improved antiproliferative and anti-AR activities compared to FDA-approved abiraterone and enzalutamide. However, induction of apoptosis in these models is independent of the AR and its truncated variant, AR-V7, and instead likely results from sustained endoplasmic reticulum stress and deregulated calcium homeostasis. Using in silico molecular docking, we predict VNPT-178 and VNLG-74A bind the ATPase domain of BiP/Grp78 and Hsp70-1A with greater affinity than the AR. Disruption of 70 kDa heat shock protein function may be the underlying mechanism of action for these galeterone analogs. Therefore, despite simultaneously antagonizing AR activity, AR and/or AR-V7 expression alone may inadequately predict a patient's response to treatment with VNPT-178 or VNLG-74A. Future studies evaluating the context-specific limitations of these compounds may provide clarity for their clinical application.

Symptoms of Allergic Rhinitis in Women during Early Pregnancy Are Associated with Higher Prevalence of Allergic Rhinitis in Their Offspring

Directory of Open Access Journals (Sweden)

Miwa Shinohara

2007-01-01

Results: Offspring whose mothers had any AR symptoms during early pregnancy showed a significantly higher adjusted odds ratio for the onset of AR in offspring than those whose mothers had no symptoms during pregnancy (adjusted Odds Ratio: 6.26, p=0.036. However, the symptoms of AR during late pregnancy showed no effects on the odds ratio. In contrast, the presence or absence of AR symptoms during early or late pregnancy showed no association with the prevalence of food allergy, atopic dermatitis or asthma in offspring. Conclusions: Our results suggest the presence of possible epigenetic mechanisms regulating the onset of AR in humans presumably through increased organ-specific hypersensitivity.

Irradiation effects of Ar cluster ion beams on Si substrates

International Nuclear Information System (INIS)

Ishii, Masahiro; Sugahara, Gaku; Takaoka, G.H.; Yamada, Isao

1993-01-01

Gas-cluster ion beams can be applied to new surface modification techniques such as surface cleaning, low damage sputtering and shallow junction formation. The effects of energetic Ar cluster impacts on solid surface were studied for cluster energies of 10-30keV. Irradiation effects were studied by RBS. For Si(111) substrates, irradiated with Ar ≥500 clusters to a dose of 1x10 15 ion/cm 2 at acceleration voltage 15kV, 2x10 14 atoms/cm 2 implanted Ar atoms were detected. In this case, the energy per cluster atom was smaller than 30eV; at this energy, no significant implantation occurs in the case of monomer ions. Ar cluster implantation into Si substrates occurred due to the high energy density irradiation. (author)

K/Ar and 40Ar/39Ar dating of emerald mineralizations from Brazil. Evidence of Transamazonian (2 Ga) and Brazilian (650 - 500 Ma) ages. Influence of phlogopite crystallo-chemistry on argon retention

International Nuclear Information System (INIS)

Ribeiro-Althoff, A.M.

1997-01-01

The emerald deposits of Brazil are always found within basic and ultra-basic formations which have been metasomatized by hydrothermal fluids, and transformed into phlogopitites. Two types of deposits may be distinguished: one associated with pegmatites, the other with shear zones. In both cases the precipitation of emerald is contemporaneous with that of phlogopite. The age of these has been determined by dating of the latter, using K-Ar and 40 Ar/ 39 Ar methods. Deposits associated with pegmatite have ages between 2.0 et 1.9 Ga (Carnaiba, Socoto), and between 650 et 500 Ma (Pombos, Juca, Pirenoplis, Capoeirana, Coqui). The Santa Terezinha deposit, associated with a shear zone where pegmatites are absent, gives an age of formation of 520 Ma. These results show that brazilian emeralds were formed during two distinct orogenic periods: the Transamazonian (2.0 Ga), in the Sao Francisco craton, and the Brasilian (650 - 500 Ma)

Shorter CAG repeat in the AR gene is associated with atypical hyperplasia and breast carcinoma

DEFF Research Database (Denmark)

De Abreu, Francine Blumental; Pirolo, Leandro Júnior; Canevari, Renata de Azevedo

2007-01-01

BACKGROUND: Previous reports into the role of [CAG]n repeat lengths in the androgen receptor (AR) gene indicate that these may play an important part in the development and progression of breast cancer, however, knowledge regarding benign breast lesions is limited. PATIENTS AND METHODS: PCR-based...

Ar Rahman-Based Dysmenorrhea Gymnastic to Reduce Pain

OpenAIRE

Sumaryani, Sri; Puspita Sari, Praditiana Indah

2015-01-01

Introduction: More than 50% dysmenorrhea are caused by excessive amounts of prostaglandin hormone during menstruation.  The combination of dysmenorrhea gymnastics and Qur'an Surah Ar-Rahman relaxation techniques is a new innovation in non-pharmacological therapy to overcome dysmenorrhoea. The purpose of this study was to determine the level of pain differences on respondents who were given dysmenorrhea gymnastics treatment, Al Quran Surah Ar-Rahman recitation, and dysmenorrhea gymnastics comb...

Low energy total cross section of 36Ar

International Nuclear Information System (INIS)

Mughabghab, S.F.; Magurno, B.A.

1975-01-01

To compare the predictions of the valence model with measured partial radiative widths of 36 Ar an accurate knowledge of the bound-level parameters is required. This is achieved by carrying out a Breit-Wigner parameter fit to the total cross section of 36 Ar measured by Chrien et al and renormalized to the recommended values of the thermal capture and scattering cross sections. (1 figure, 1 table) (U.S.)

Aurora Kinase A Promotes AR Degradation via the E3 Ligase CHIP.

Science.gov (United States)

Sarkar, Sukumar; Brautigan, David L; Larner, James M

2017-08-01

Reducing the levels of the androgen receptor (AR) is one of the most viable approaches to combat castration-resistant prostate cancer. Previously, we observed that proteasomal-dependent degradation of AR in response to 2-methoxyestradiol (2-ME) depends primarily on the E3 ligase C-terminus of HSP70-interacting protein (STUB1/CHIP). Here, 2-ME stimulation activates CHIP by phosphorylation via Aurora kinase A (AURKA). Aurora A kinase inhibitors and RNAi knockdown of Aurora A transcript selectively blocked CHIP phosphorylation and AR degradation. Aurora A kinase is activated by 2-ME in the S-phase as well as during mitosis, and phosphorylates CHIP at S273. Prostate cancer cells expressing an S273A mutant of CHIP have attenuated AR degradation upon 2-ME treatment compared with cells expressing wild-type CHIP, supporting the idea that CHIP phosphorylation by Aurora A activates its E3 ligase activity for the AR. These results reveal a novel 2-ME→Aurora A→CHIP→AR pathway that promotes AR degradation via the proteasome that may offer novel therapeutic opportunities for prostate cancer. Mol Cancer Res; 15(8); 1063-72. ©2017 AACR . ©2017 American Association for Cancer Research.

{sup 40}Ar/{sup 39}Ar dating and paleo-magnetism of traps from Ethiopia, Deccan and Siberia; Datation {sup 40}Ar/{sup 39}Ar et paleomagnetisme des traps d'Ethiopie, du Deccan et de Siberie

Energy Technology Data Exchange (ETDEWEB)

Hofmann, C

1997-01-01

Recent studies have shown that major flood basalt provinces have been emplaced as short events ({approx} 1 Myr), more or less synchronous with climatic crises and mass extinctions. We present new geochronologic ({sup 40}Ar/{sup 39}Ar) and magneto-stratigraphic results for the Ethiopian traps, one of the last remaining flood basalts for which little of such data were available. The ages obtained in a 2000 m thick section are indistinguishable. Moreover, magneto-stratigraphy reveals a simple 3-chron reverse-normal-reverse sequence. Although magnetic chrons cannot be yet unambiguously identified, there is more likelihood for the normal sub-chron in the main basaltic pile to correspond to 11N, supporting a brief duration (less than 1.5 Ma). The Ethiopian traps erupted near 30 Ma at or near the time of the cold and dry climate, major Antarctic ice sheet advance, and the largest sea-level drop in the Tertiary. Bhandari et al. (GRL, 1995) have discovered inter-traps sediments with a triple iridium anomaly in a series of seven basaltic lava flows in the Kutch area of the North Western Deccan traps of India. Plagioclases from three flows above the iridium bearing sediments yield {sup 39}Ar/{sup 40}Ar plateau ages near 65.0 Ma: these flows have unambiguously reversed magnetic polarity interpreted as chron 29R. As a preliminary summary, evidence of the KTB asteroid impact is confirmed in the Deccan traps, showing that they are coeval events in a general sense (in a Ma long window) though clearly with vastly different time constants. This is compatible with paleontologic evidence of two scales of extinctions, one quasi-instantaneous and the other on the order of 10{sup 5} to 10{sup 6} yrs. Clearly, the impact cannot have caused trap eruptions. On the other hand, the exact age and significance of the lower flows more altered remains to be analyzed further as they pertained to the much debated question of duration of Deccan trap volcanism. (author)

Trapping of N 2, CO and Ar in amorphous ice—Application to comets

Science.gov (United States)

Bar-Nun, A.; Notesco, G.; Owen, T.

2007-10-01

Recent attempts using high resolution spectra to detect N +2 in several comets were unsuccessful [Cochran, A.L., Cochran, W.D., Baker, E.S., 2000. Icarus 146, 583-593; Cochran, A.L., 2002. Astrophys. J. 576, L165-L168]. The upper limits on N +2 in comparison with the positively detected CO + for Comets C/1995 O1 Hale-Bopp, 122P/1995 S1 de Vico and 153P/2002 C1 Ikeya-Zhang range between N2+/COLisse, C.M., Shemansky, D.E., 2002. Astrophys. J. 576, L95-L98], with upper limits of Ar/COLisse, C.M., Shemansky, D.E., 2002. Astrophys. J. 576, L95-L98] non-detection of Ar. However, with an extreme starting value for N 2/CO = 0.22 in the region where the ice grains which agglomerated to produce comet nuclei were formed, the expected N 2/CO ratio in the cometary ice should be 6.6×10, much higher than its non-detection limit.

"Ars Electronica 2009" / Raivo Kelomees

Index Scriptorium Estoniae

Kelomees, Raivo, 1960-

2009-01-01

30. "Ars Electronica" festival "Human Nature" ("Inimese loomus") Linzis. Osaka ülikooli professori Hiroshi Ishiguro mehaanilis-digitaalsest nukust. Hübriidkunsti kategoorias peapreemia saanud Eduardo Kaci inimtaimest. Konverentsidest. Näitusest "See this Sound", mis oli pühendatud helile kujutavas kunstis

40Ar-39Ar age clustering in the active phonolitic Cadamosto Seamount (Cape Verdes): Indications for periodic magmatic activity

Science.gov (United States)

Samrock, L. K.; Hansteen, T. H.; Wartho, J. A.

2017-12-01

The Cape Verde archipelago is situated 400-800 km off the west coast of Africa and is comprised of a northern and southern chain of islands and seamounts. Morphological observations and previous radiometric dating of the islands indicate a slow age progression, over 22 Ma, from east to west (Holm et al. 2008). We present the first radiometric ages for Cadamosto Seamount, which is composed of complex evolved volcanics and is situated at the southwestern tip of the Cape Verde archipelago (e.g. Barker et al. 2012). We analyzed five different submarine phonolites that were sampled by remotely operated vehicles (ROV) Kiel 6000 and dredging during the RV Meteor (M80/3) and RV Poseidon (POS320/2) cruises. Fresh sanidine, nepheline, and biotite grains were selected and carefully prepared for 40Ar-39Ar single grain total fusion analysis. Sanidine single grain 40Ar-39Ar ages from 5 samples range from 11.5 ± 6.5 ka to 349.0 ± 20.4 ka (2σ errors), and cluster in several age groupings (using the decay constant and atmospheric air ratio of Steiger & Jäger (1977), and age standard TCS2 (27.87 ± 0.04 Ma; 1σ; M.A. Lanphere, pers. comm.)). Three age groups can be identified within the youngest (0-170 ka) sanidines, which are separated by periods of 52-54 ka. Nepheline grains from one sample yielded much older ages of 169.5 ± 16.5 ka to 1521.5 ± 8.3 ka (2σ). Our data suggests young ages for the Cadamosto Seamount, which is in accordance with recorded seismic activity (Grevemeyer et al. 2010), and its position adjacent to the recently active islands of Fogo (last eruption in 2014/2015) and Brava (recent seismic activity). The different sub-groups of sanidine 40Ar-39Ar ages can be used to identify different activity maxima corresponding to cycles of magmatic productivity in a long-lived magmatic system. Ongoing petrologic investigations will be used to identify the relative importance of processes such as mantle melting rates, magma replenishment and magma chamber processes

Cooling, exhumation, and deformation in the Hindu Kush, NW Pakistan: New constraints from preliminary 40Ar/39Ar and fission track analyses

Science.gov (United States)

Faisal, Shah; Larson, Kyle P.; Camacho, Alfredo; Coutand, Isabelle

2018-06-01

Asian crust in the Hindu Kush region in northern Pakistan records a protracted history of rifting, subduction and collision not commonly preserved within the Himalaya. Because of this, it is key to understanding the development of the southern Eurasian margin both prior to and after collision with India. New mica 40Ar/39Ar and apatite fission track geochronologic data from this region provide constraints on the kinematics of the Hindu Kush. 40Ar/39Ar muscovite and biotite ages from the late Cambrian Kafiristan pluton are 379.7 ± 1.7 Ma and 47.2 ± 0.3 Ma, respectively. The muscovite age may record cooling or partial resetting, while the biotite age is interpreted to record a thermal disruption associated with the early stages of continental collision in the Himalayan system. A 111.0 ± 0.6 Ma muscovite age from the northern part of the Tirich Mir pluton (∼123 Ma old; U-Pb) is interpreted to indicate a recrystallization event ∼12 Myrs after its intrusion. In addition, a younger muscovite age of 47.5 ± 0.2 Ma was derived from the opposite side of the same pluton in the immediate hanging wall of the Tirich Mir fault. This Eocene age is interpreted to represent the time of recrystallization during fault (re)activation in the early stages of India-Asia continent-continent collision. 40Ar/39Ar biotite analysis from the Buni-Zom pluton yields an age of 61.6 ± 1.1 Ma and is interpreted to reflect cooling at mid-upper crustal levels subsequent to the pluton's emplacement in the middle Cretaceous. Finally, 17.1-21.3 Ma 40Ar/39Ar ages from the Garam Chasma pluton and surrounding metapelites indicate cooling immediately following crystallization of the leucogranite body in the earliest Miocene/latest Oligocene. The younger cooling history is resolved by fission track dating of apatite (AFT). In the vicinity of the bounding Tirich Mir fault, the Tirich Mir pluton yields an AFT age of 1.4 ± 0.3 Ma, which is consistent with active exhumation associated with the surface

ArControl: An Arduino-Based Comprehensive Behavioral Platform with Real-Time Performance.

Science.gov (United States)

Chen, Xinfeng; Li, Haohong

2017-01-01

Studying animal behavior in the lab requires reliable delivering stimulations and monitoring responses. We constructed a comprehensive behavioral platform (ArControl: Arduino Control Platform) that was an affordable, easy-to-use, high-performance solution combined software and hardware components. The hardware component was consisted of an Arduino UNO board and a simple drive circuit. As for software, the ArControl provided a stand-alone and intuitive GUI (graphical user interface) application that did not require users to master scripts. The experiment data were automatically recorded with the built in DAQ (data acquisition) function. The ArControl also allowed the behavioral schedule to be entirely stored in and operated on the Arduino chip. This made the ArControl a genuine, real-time system with high temporal resolution (<1 ms). We tested the ArControl, based on strict performance measurements and two mice behavioral experiments. The results showed that the ArControl was an adaptive and reliable system suitable for behavioral research.

Paleomagnetism and 40Ar / 39Ar Geochronology of Yemeni Oligocene volcanics: Implications for timing and duration of Afro-Arabian traps and geometry of the Oligocene paleomagnetic field

Science.gov (United States)

Riisager, Peter; Knight, Kim B.; Baker, Joel A.; Ukstins Peate, Ingrid; Al-Kadasi, Mohamed; Al-Subbary, Abdulkarim; Renne, Paul R.

2005-09-01

A combined paleomagnetic and 40Ar / 39Ar study was carried out along eight stratigraphically overlapping sections in the Oligocene Afro-Arabian flood volcanic province in Yemen (73 sites). The composite section covers the entire volcanic stratigraphy in the sampling region and represents five polarity zones that are correlated to the geomagnetic polarity time scale based on 40Ar / 39Ar ages from this and previous studies. The resulting magnetostratigraphy is similar to that of the conjugate margin in Ethiopia. The earliest basaltic volcanism took place in a reverse polarity chron that appears to correspond to C11r, while the massive rhyolitic ignimbrite eruptions correlated to ash layers in Oligocene Indian Ocean sediment 2700 km away from the Afro-Arabian traps, appear to have taken place during magnetochron C11n. The youngest ignimbrite was emplaced during magnetochron C9n. Both 40Ar / 39Ar and paleomagnetic data suggest rapid Red Sea. By analyzing Afro-Arabian paleomagnetic data in conjunction with contemporaneous paleomagnetic poles available from different latitudes we argue that the Oligocene paleomagnetic field was dominated by the axial dipole with insignificant non-dipole field contributions.

H{sub 2}-Ar dilution for improved c-Si quantum dots in P-doped SiN{sub x}:H thin film matrix

Energy Technology Data Exchange (ETDEWEB)

Liu, Jia [Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi’an 710119 (China); Zhang, Weijia, E-mail: zwjghx@126.com [Center of Condensed Matter and Material Physics, School of Physics and Nuclear Energy Engineering, Beihang University, Beijing, 100191 (China); Liu, Shengzhong, E-mail: szliu@dicp.ac.cn [Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering, Shaanxi Normal University, Xi’an 710119 (China); State key Laboratory of Catalysis, iChEM, Dalian Institute of Chemical Physics, Dalian National Laboratory for Clean Energy, Chinese Academy of Sciences, Dalian 116023 (China)

2017-02-28

Highlights: • Phosphorous-doped SiN{sub x}:H thin films containing c-Si QDs were prepared by PECVD in H{sub 2}-Ar mixed dilution under low temperature. • QD density and QD size can be controlled by tuning H{sub 2}/Ar flow ratio. • The sample prepared at the H{sub 2}/Ar flow ratio of 100/100 possesses both wide band gap and excellent conductivity. • Detail discussion has been presented for illustrating the influence of H{sub 2}/Ar mixed dilution on the crystallization process and P-doping. - Abstract: Phosphorus-doped hydrogenated silicon nitride (SiN{sub x}:H) thin films containing crystalline silicon quantum dot (c-Si QD) was prepared by plasma enhanced chemical vapor deposition (PECVD) using hydrogen-argon mixed dilution. The effects of H{sub 2}/Ar flow ratio on the structural, electrical and optical characteristics of as-grown P-doped SiN{sub x}:H thin films were systematically investigated. Experimental results show that crystallization is promoted by increasing the H{sub 2}/Ar flow ratio in dilution, while the N/Si atomic ratio is higher for thin film deposited with argon-rich dilution. As the H{sub 2}/Ar flow ratio varies from 100/100 to 200/0, the samples exhibit excellent conductivity owing to the large volume fraction of c-Si QDs and effective P-doping. By adjusting the H{sub 2}/Ar ratio to 100/100, P-doped SiN{sub x}:H thin film containing tiny and densely distributed c-Si QDs can be obtained. It simultaneously possesses wide optical band gap and high dark conductivity. Finally, detailed discussion has been made to analyze the influence of H{sub 2}-Ar mixed dilution on the properties of P-doped SiN{sub x}:H thin films.

Augmented Reality Reading Support in Higher Education: Exploring Effects on Perceived Motivation and Confidence in Comprehension for Struggling Readers in Higher Education

Science.gov (United States)

Huisinga, Laura Anne

2017-01-01

Technology has shown promise to aid struggling readers in higher education, particularly through new and emerging technologies. Augmented reality (AR) has been used successfully in the classroom to motivate and engage struggling learners, yet little research exists on how augmented print might help struggling readers. This study explores this gap,…

Modification of van La ar activity coefficient model

International Nuclear Information System (INIS)

Vakili-Nezhaad, G. R.; Modarress, H.; Mansoori, G. A.

2001-01-01

Based on statistical and mechanical arguments, the original van La ar activity coefficient model has been improved by reasonable assumptions. This modifications has been done by replacing the van der Waals equation of state with the Redlich-K wong equation of state in the formulation of van La ar with consistent mixing rules for the energy and volume parameters of this equation of state (a mix , b mix ). Other equations of state, such as the Soave modification of the Redlich-K wong equation of state, P eng-Robinson and Mohsen-Nia, Modarress and Mansoori equations of state, have been introduced in the formulation of van La ar for the activity coefficients of the components present in the binary liquid mixtures, and their effects on the accuracy of the resultant activity coefficient models have been examined. The results of these revised models have been compared with the experimental data and it was found that the Redlich-K wong equation of state with the van der Waals mixing rules for the volume and energy parameters of this equation, is the best choice among these equations of state. In addition, it can improve the original van La ar activity coefficient model and, therefore a better agreement with the experimental data is obtained

77 FR 17363 - Proposed Establishment of Class E Airspace; West Memphis, AR

Science.gov (United States)

2012-03-26

...-0155; Airspace Docket No. 12-ASW-1] Proposed Establishment of Class E Airspace; West Memphis, AR AGENCY... action proposes to establish Class E airspace at West Memphis, AR. Separation of existing Class E... surface at West Memphis, AR, to accommodate the separation of existing Class E airspace surrounding West...

Behaviour of AR glass fibre for building structural applications

Directory of Open Access Journals (Sweden)

Miravete, A.

2005-12-01

Full Text Available The AR glass reinforcement fibres were designed to resist the alkalis from the concrete. This is the main reason for its utilisation as a short-fibre-reinforcement of mortar and concrete for the last decades. Originally, the AR glass fibre sizing was not compatible with synthetic resins, so that this type of reinforcement was applied exclusively to mortar and concrete matrices. Recently, due to the developments of sizing, which are compatible with synthetic resins, the AR- glass fibres may be used as reinforcement of organic matrix composite materials, broadening the range of structural applications. The mechanical properties of AR glass fibre and organic matrix composite materials will be studied in this paper. First, the behaviour of this material under stress corrosion will be analysed. Their mass loss will be compared to E, C, and boron free glass fibres. Second, an experimental study dealing with 3P test bending and short beam ofAR glass fibre/polyester will de described with the goal of obtaining their Young modulus and tensile and interlaminar shear strengths. Finally, these experimental results will be compared to E glass fibre/polyester and several conclusions about their structural applications will be drawn.

El vidrio AR y su presentación en forma de fibras de refuerzo, fue diseñado para ser inerte a los álcalis de los cementos. Por este motivo se viene utilizando desde hace varias décadas como refuerzo de morteros y hormigones en forma de fibra corta. El ensimaje que estas fibras de vidrio de refuerzo A R presentaba en su origen no era compatible con resinas de tipo sintéticas, por lo que el refuerzo era exclusivo para cementos y hormigones fuera cual fuera la aplicación, formato o proceso productivo. Recientemente, gracias al desarrollo específico de ensimajes especiales acordes a las fibras de vidrio AR ha aparecido la misma tipología de vidrio AR como refuerzo en forma de fibra continua compatible con resinas sint

Insights from zebrafish and mouse models on the activity and safety of ar-turmerone as a potential drug candidate for the treatment of epilepsy.

Directory of Open Access Journals (Sweden)

Adriana Monserrath Orellana-Paucar

Full Text Available In a previous study, we uncovered the anticonvulsant properties of turmeric oil and its sesquiterpenoids (ar-turmerone, α-, β-turmerone and α-atlantone in both zebrafish and mouse models of chemically-induced seizures using pentylenetetrazole (PTZ. In this follow-up study, we aimed at evaluating the anticonvulsant activity of ar-turmerone further. A more in-depth anticonvulsant evaluation of ar-turmerone was therefore carried out in the i.v. PTZ and 6-Hz mouse models. The potential toxic effects of ar-turmerone were evaluated using the beam walking test to assess mouse motor function and balance. In addition, determination of the concentration-time profile of ar-turmerone was carried out for a more extended evaluation of its bioavailability in the mouse brain. Ar-turmerone displayed anticonvulsant properties in both acute seizure models in mice and modulated the expression patterns of two seizure-related genes (c-fos and brain-derived neurotrophic factor [bdnf] in zebrafish. Importantly, no effects on motor function and balance were observed in mice after treatment with ar-turmerone even after administering a dose 500-fold higher than the effective dose in the 6-Hz model. In addition, quantification of its concentration in mouse brains revealed rapid absorption after i.p. administration, capacity to cross the BBB and long-term brain residence. Hence, our results provide additional information on the anticonvulsant properties of ar-turmerone and support further evaluation towards elucidating its mechanism of action, bioavailability, toxicity and potential clinical application.

Insights from zebrafish and mouse models on the activity and safety of ar-turmerone as a potential drug candidate for the treatment of epilepsy.

Science.gov (United States)

Orellana-Paucar, Adriana Monserrath; Afrikanova, Tatiana; Thomas, Joice; Aibuldinov, Yelaman K; Dehaen, Wim; de Witte, Peter A M; Esguerra, Camila V

2013-01-01

In a previous study, we uncovered the anticonvulsant properties of turmeric oil and its sesquiterpenoids (ar-turmerone, α-, β-turmerone and α-atlantone) in both zebrafish and mouse models of chemically-induced seizures using pentylenetetrazole (PTZ). In this follow-up study, we aimed at evaluating the anticonvulsant activity of ar-turmerone further. A more in-depth anticonvulsant evaluation of ar-turmerone was therefore carried out in the i.v. PTZ and 6-Hz mouse models. The potential toxic effects of ar-turmerone were evaluated using the beam walking test to assess mouse motor function and balance. In addition, determination of the concentration-time profile of ar-turmerone was carried out for a more extended evaluation of its bioavailability in the mouse brain. Ar-turmerone displayed anticonvulsant properties in both acute seizure models in mice and modulated the expression patterns of two seizure-related genes (c-fos and brain-derived neurotrophic factor [bdnf]) in zebrafish. Importantly, no effects on motor function and balance were observed in mice after treatment with ar-turmerone even after administering a dose 500-fold higher than the effective dose in the 6-Hz model. In addition, quantification of its concentration in mouse brains revealed rapid absorption after i.p. administration, capacity to cross the BBB and long-term brain residence. Hence, our results provide additional information on the anticonvulsant properties of ar-turmerone and support further evaluation towards elucidating its mechanism of action, bioavailability, toxicity and potential clinical application.

Numerical simualtion of underground 37Ar transportation to the ground

International Nuclear Information System (INIS)

She Ruogu; Li Hua; Liu Cheng'an; Wu Jun

2008-01-01

Monitoring radioactive gas 37 Ar is an important technique for the On-Site Inspection(OSI) of the Comprehensive Nuclear Test Ban Treaty (CTBT) verification regime. In order to establish a theoretical model that can be used to calculate the appearing time and radioactivity of 37 Ar which transports to the ground after a nuclear explosion, the rock media in the test area is assumed to be a homogeneous porous media, without consideration of gas absorption by and release from the rock media. The seepage model in the porous media is used to calculate 37 Ar transportation. Computational results give the time 37 Ar leaks to the ground and the variation of its radioactivity with time. And we can analyze and consider the computational results when we have developed OSI noble gas monitoring systems and evaluated their effectiveness. (authors)

CERN inspires 2011 edition of the ARS Electronica Digital Arts Festival

CERN Multimedia

Jordan Juras

2011-01-01

This year’s annual ARS Electronica Digital Arts Festival featured CERN as the springboard for its theme, ORIGIN – How it All Begins. The prestigious digital arts festival also served as the perfect venue to launch the Collide@CERN project.   Colours and Lights at the ARS Electronica Digital Arts Festival in Linz (Austria). (Photo by Claudia Marcelloni) The CERN cultural policy project, announced at the beginning of 2011 has started to gain momentum. Ariane Koek, art specialist for the Communication Group, received confirmation in May that ARS Electronica had chosen her proposal to use CERN as the primary source of inspiration for their annual ARS Electronica Festival. This marks the first of the cultural policy’s arts partnerships. The world-renowned celebration for the digital arts is held annually in Linz, Austria, where, amongst the incredible collection of displays and productions, the Prix ARS Electronica – the Oscars of the digital arts world -&...

An analysis of the 1977 AD/AR TARSLL.

OpenAIRE

Hargrove, James Wiley Jr.

1980-01-01

Approved for public release; distribution is unlimited The industrial mission of Destroyer Tenders (AD) and Repair Ships (AR) is to provide intermediate level maintenance and repair for supported ships. The Tender and Repair Ship Load List for these ships (AD/AR TARSLL) designates the range (number) and depth (quantity) of repair parts to be carried to support this industrial mission. This thesis details the logical reasoning and mathematical theory used to develop the...

ID4 promotes AR expression and blocks tumorigenicity of PC3 prostate cancer cells

International Nuclear Information System (INIS)

Komaragiri, Shravan Kumar; Bostanthirige, Dhanushka H.; Morton, Derrick J.; Patel, Divya; Joshi, Jugal; Upadhyay, Sunil; Chaudhary, Jaideep

2016-01-01

Deregulation of tumor suppressor genes is associated with tumorigenesis and the development of cancer. In prostate cancer, ID4 is epigenetically silenced and acts as a tumor suppressor. In normal prostate epithelial cells, ID4 collaborates with androgen receptor (AR) and p53 to exert its tumor suppressor activity. Previous studies have shown that ID4 promotes tumor suppressive function of AR whereas loss of ID4 results in tumor promoter activity of AR. Previous study from our lab showed that ectopic ID4 expression in DU145 attenuates proliferation and promotes AR expression suggesting that ID4 dependent AR activity is tumor suppressive. In this study, we examined the effect of ectopic expression of ID4 on highly malignant prostate cancer cell, PC3. Here we show that stable overexpression of ID4 in PC3 cells leads to increased apoptosis and decreased cell proliferation and migration. In addition, in vivo studies showed a decrease in tumor size and volume of ID4 overexpressing PC3 cells, in nude mice. At the molecular level, these changes were associated with increased androgen receptor (AR), p21, and AR dependent FKBP51 expression. At the mechanistic level, ID4 may regulate the expression or function of AR through specific but yet unknown AR co-regulators that may determine the final outcome of AR function. - Highlights: • ID4 expression induces AR expression in PC3 cells, which generally lack AR. • ID4 expression increased apoptosis and decreased cell proliferation and invasion. • Overexpression of ID4 reduces tumor growth of subcutaneous xenografts in vivo. • ID4 induces p21 and FKBP51 expression- co-factors of AR tumor suppressor activity.

ID4 promotes AR expression and blocks tumorigenicity of PC3 prostate cancer cells

Energy Technology Data Exchange (ETDEWEB)

Komaragiri, Shravan Kumar; Bostanthirige, Dhanushka H.; Morton, Derrick J.; Patel, Divya; Joshi, Jugal; Upadhyay, Sunil; Chaudhary, Jaideep, E-mail: jchaudhary@cau.edu

2016-09-09

Deregulation of tumor suppressor genes is associated with tumorigenesis and the development of cancer. In prostate cancer, ID4 is epigenetically silenced and acts as a tumor suppressor. In normal prostate epithelial cells, ID4 collaborates with androgen receptor (AR) and p53 to exert its tumor suppressor activity. Previous studies have shown that ID4 promotes tumor suppressive function of AR whereas loss of ID4 results in tumor promoter activity of AR. Previous study from our lab showed that ectopic ID4 expression in DU145 attenuates proliferation and promotes AR expression suggesting that ID4 dependent AR activity is tumor suppressive. In this study, we examined the effect of ectopic expression of ID4 on highly malignant prostate cancer cell, PC3. Here we show that stable overexpression of ID4 in PC3 cells leads to increased apoptosis and decreased cell proliferation and migration. In addition, in vivo studies showed a decrease in tumor size and volume of ID4 overexpressing PC3 cells, in nude mice. At the molecular level, these changes were associated with increased androgen receptor (AR), p21, and AR dependent FKBP51 expression. At the mechanistic level, ID4 may regulate the expression or function of AR through specific but yet unknown AR co-regulators that may determine the final outcome of AR function. - Highlights: • ID4 expression induces AR expression in PC3 cells, which generally lack AR. • ID4 expression increased apoptosis and decreased cell proliferation and invasion. • Overexpression of ID4 reduces tumor growth of subcutaneous xenografts in vivo. • ID4 induces p21 and FKBP51 expression- co-factors of AR tumor suppressor activity.

Bartlett correction in the stable AR(1) model with intercept and trend

NARCIS (Netherlands)

van Giersbergen, N.P.A.

2004-01-01

The Bartlett correction is derived for testing hypotheses about the autoregressive parameter ρ in the stable: (i) AR(1) model; (ii) AR(1) model with intercept; (iii) AR(1) model with intercept and linear trend. The correction is found explicitly as a function of ρ. In the models with deterministic

Comparison of Ne and Ar seeded radiative divertor plasmas in JT-60U

Energy Technology Data Exchange (ETDEWEB)

Nakano, T., E-mail: nakano.tomohide@jaea.go.jp

2015-08-15

In H-mode plasmas with Ne, Ar and a mixture of Ne and Ar injection, the divertor radiation power fractions amongst these impurities in addition to an intrinsic impurity, C, are investigated. In plasmas with the inner divertor plasma attached, carbon is the biggest radiator, whichever impurity, Ne, Ar or a mixture of Ar and Ne is injected. In contrast, in plasmas with the inner divertor plasma detached, Ne is the biggest radiator due to a significantly high recombination radiation from Ne VIII. Ar is always a minor contributor in plasmas with the inner divertor both attached and detached.

Essential Characteristics of Plasma Antennas Filled with He-Ar Penning Gases

International Nuclear Information System (INIS)

Sun Naifeng; Li Wenzhong; Wang Shiqing; Li Jian; Ci Jiaxiang

2012-01-01

Based on the essential theory of Penning gases, the discharge characteristics of He-Ar Penning gases in insulating tubes were analyzed qualitatively. The relation between the effective length of an antenna column filled with He-Ar Penning gases and the applied radio frequency (RF) power was investigated both theoretically and experimentally. The distribution of the plasma density along the antenna column in different conditions was studied. The receiving characteristics of local frequency modulated (FM) electromagnetic waves by the plasma antenna filled with He-Ar Penning gases were compared with those by an aluminum antenna with the same dimensions. Results show that it is feasible to take plasma antennas filled with He-Ar Penning gases as receiving antennas.

Recoil ion charge state distributions in low energy Arq+ - Ar collisions

International Nuclear Information System (INIS)

Vancura, J.; Marchetti, V.; Kostroun, V.O.

1992-01-01

We have measured the recoil ion charge state distributions in Ar q+ -- Ar (8≤q≤16) collisions at 2.3 qkeV and 0.18qkeV by time of flight (TOF) spectroscopy. For Ar 8-16+ , recoil ion charge states up to 6+ are clearly present, indicating that the 3p subshell in the target atom is being depleted, while for Ar 10-16+ , there is evidence that target 3s electrons are also being removed. Comparison of the recoil ion charge state spectra at 2.3 and 0.18 qkeV shows that for a given projectile charge, there is very little dependence of the observed recoil target charge state distribution on projectile energy

Electron transfer from H2 and Ar to stored multiply charged argon ions produced by synchrotron radiation

International Nuclear Information System (INIS)

Kravis, S.D.; Church, D.A.; Johnson, B.M.; Meron, M.; Jones, K.W.; Levin, J.C.; Sellin, I.A.; Azuma, Y.; Berrah-Mansour, N.; Berry, H.G.; Druetta, M.

1992-01-01

The rate coefficients for electron transfer from Ar and H 2 to Ar q+ ions (3≤q≤6) have been measured using an ion-storage technique in a Penning ion trap. The ions were produced in the trap by K-shell photoionization of Ar atoms, using broadband synchrotron x-ray radiation. K-electron removal resulted in vacancy cascading, yielding a distribution of argon-ion charge states peaked near Ar 4+ . The stored ion gas had an initial temperature near 480 K. The basic data determining the rate coefficients k(Ar q+ ) are the storage time constants of each charge state in the trap, in the presence of a measured pressure of target gas. The results of the measurements (in units of 10 -9 cm 3 s -1 ) are k(Ar 3+ ,H 2 )=4.3(0.7), k(Ar 3+ ,Ar)=1.6(0.2), k(Ar 4+ ,H 2 )=5.2(0.6), k(Ar 4+ ,Ar)=2.5(0.3), k(Ar 5+ ,H 2 )=5.9(0.7), k(Ar 5+ ,Ar)=2.9(0.3), k(Ar 6+ ,H 2 )=8.5(1.2), and k(Ar 6+ ,Ar)=2.5(0.3)