Continuous and selective measurement of oxytocin and vasopressin using boron-doped diamond electrodes

NASA Astrophysics Data System (ADS)

Asai, Kai; Ivandini, Tribidasari A.; Einaga, Yasuaki

2016-09-01

The electrochemical detection of oxytocin using boron-doped diamond (BDD) electrodes was studied. Cyclic voltammetry of oxytocin in a phosphate buffer solution exhibits an oxidation peak at +0.7 V (vs. Ag/AgCl), which is attributable to oxidation of the phenolic group in the tyrosyl moiety. Furthermore, the linearity of the current peaks obtained in flow injection analysis (FIA) using BDD microelectrodes over the oxytocin concentration range from 0.1 to 10.0 μM with a detection limit of 50 nM (S/N = 3) was high (R2 = 0.995). Although the voltammograms of oxytocin and vasopressin observed with an as-deposited BDD electrode, as well as with a cathodically-reduced BDD electrode, were similar, a clear distinction was observed with anodically-oxidized BDD electrodes due to the attractive interaction between vasopressin and the oxidized BDD surface. By means of this distinction, selective measurements using chronoamperometry combined with flow injection analysis at an optimized potential were demonstrated, indicating the possibility of making selective in situ or in vivo measurements of oxytocin.

A practical guide to using boron doped diamond in electrochemical research.

PubMed

Macpherson, Julie V

2015-02-07

Conducting, boron doped diamond (BDD), in addition to its superior material properties, offers several notable attributes to the electrochemist making it an intriguing material for electrochemical research. These include the widest solvent window of all electrode materials; low background and capacitive currents; reduced fouling compared to other electrodes and; the ability to withstand extreme potentials, corrosive and high temperature/pressure environments. However, BDD is not your typical electrode material, it is a semi-conductor doped degenerately with boron to present semi-metallic characteristics. Input from materials scientists, chemists and physicists has been required to aid understanding of how to work with this material from an electrochemical viewpoint and improve electrode quality. Importantly, depending on how the BDD has been grown and then subsequently treated, prior to electrochemical measurement, the resulting material properties can vary quite significantly from one electrode to the next. This likely explains the variability seen by different researchers working on the same experimental systems. The aim of this "protocols" article is not to provide a state-of-the-art review of diamond electrochemistry, suitable references are provided to the interested reader, but instead serves as a reference point for any researcher wishing to commence work with diamond electrodes and interpret electrochemical data. It provides information on how best to characterise the material properties of the electrode before use and outlines the interplay between boron dopant density, non-diamond-carbon content, grain morphology, surface chemistry and redox couple identity. All should ideally be considered when interpretating electrochemical data arising from the diamond electrode. This will aid the reader in making meaningful comparisons between data obtained by different researchers using different diamond electrodes. The guide also aims to help educate the researcher in choosing which form of BDD is best suited to their research application.

Preparation of hemoglobin-modified boron-doped diamond for acrylamide biosensors

NASA Astrophysics Data System (ADS)

Umam, K.; Saepudin, E.; Ivandini, T. A.

2017-04-01

Boron-doped diamond (BDD) electrode was modified with haemoglobin to develop electrochemical biosensors of acrylamide. Prior to modify with haemoglobin, the BDD was modified by gold nanoparticles to increase the affinity of BDD against haemoglobin. The electrochemical behaviour of the electrode in the presence of acrylamide was studied in comparison to haemoglobin-modified gold electrodes. Cyclic voltammetry indicated the optimum responses in 0.1 M sodium acetate buffer at pH 5. The responses were linear to the acrylamide concentration range of 5-50 μM with an estimated detection limit of 5.14 μM, suggesting that the electrode was promising for acrylamide biosensors.

The Effects of Boron Doping on Residual Stress of Hfcvd Diamond Film for Mems Applications

NASA Astrophysics Data System (ADS)

Zhao, Tianqi; Wang, Xinchang; Sun, Fanghong

In this study, the residual stress of boron-doped diamond (BDD) films is investigated as a function of boron doping level using X-ray diffraction (XRD) analysis. Boron doping level is controlled from 1000ppm to 9000ppm by dissolving trimethyl borate into acetone. BDD films are deposited on silicon wafers using a bias-enhanced hot filament chemical vapor deposition (BE-HFCVD) system. Residual stress calculated by sin2 ψ method varies linearly from -2.4GPa to -1.1GPa with increasing boron doping level. On the BDD film of -1.75GPa, free standing BDD cantilevers are fabricated by photolithography and ICP-RIE processes, then tested by laser Doppler vibrometer (LDV). A cantilever with resonant frequency of 183KHz and Q factor of 261 in the air is fabricated.

Chemical Modification of Boron-Doped Diamond Electrodes for Applications to Biosensors and Biosensing.

PubMed

Svítková, Jana; Ignat, Teodora; Švorc, Ľubomír; Labuda, Ján; Barek, Jiří

2016-05-03

Boron-doped diamond (BDD) is a prospective electrode material that possesses many exceptional properties including wide potential window, low noise, low and stable background current, chemical and mechanical stability, good biocompatibility, and last but not least exceptional resistance to passivation. These characteristics extend its usability in various areas of electrochemistry as evidenced by increasing number of published articles over the past two decades. The idea of chemically modifying BDD electrodes with molecular species attached to the surface for the purpose of creating a rational design has found promising applications in the past few years. BDD electrodes have appeared to be excellent substrate materials for various chemical modifications and subsequent application to biosensors and biosensing. Hence, this article presents modification strategies that have extended applications of BDD electrodes in electroanalytical chemistry. Different methods and steps of surface modification of this electrode material for biosensing and construction of biosensors are discussed.

Benzene oxidation at diamond electrodes: comparison of microcrystalline and nanocrystalline diamonds.

PubMed

Pleskov, Yu V; Krotova, M D; Elkin, V V; Varnin, V P; Teremetskaya, I G; Saveliev, A V; Ralchenko, V G

2012-08-27

A comparative study of benzene oxidation at boron-doped diamond (BDD) and nitrogenated nanocrystalline diamond (NCD) anodes in 0.5 M K(2)SO(4) aqueous solution is conducted by using cyclic voltammetry and electrochemical impedance spectroscopy. It is shown by measurements of differential capacitance and anodic current that during the benzene oxidation at the BDD electrode, adsorption of a reaction intermediate occurs, which partially blocks the electrode surface and lowers the anodic current. At the NCD electrode, benzene is oxidized concurrently with oxygen evolution, a (quinoid) intermediate being adsorbed at the electrode. The adsorption and the electrode surface blocking are reflected in the impedance-frequency and impedance-potential complex-plane plots. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Enhancement of surface area and wettability properties of boron doped diamond by femtosecond laser-induced periodic surface structuring

DOE PAGES

Granados, Eduardo; Calderon, Miguel Martinez; Krzywinski, Jacek; ...

2017-08-28

We demonstrate the formation of laser-induced periodic surface structures (LIPSS) in boron-doped diamond (BDD) by irradiation with femtosecond near-IR laser pulses. The results show that the obtained LIPSS are perpendicular to the laser polarization, and the ripple periodicity is on the order of half of the irradiation wavelength. The surface structures and their electrochemical properties were characterized using Raman micro-spectroscopy, in combination with scanning electron and atomic force microscopies. The textured BDD surface showed a dense and large surface area with no change in its structural characteristics. The effective surface area of the textured BDD electrode was approximately 50% largermore » than that of a planar substrate, while wetting tests showed that the irradiated area becomes highly hydrophilic. Lastly, our results indicate that LIPSS texturing of BDD is a straightforward and simple technique for enhancing the surface area and wettability properties of the BDD electrodes, which could enable higher current efficiency and lower energy consumption in the electrochemical oxidation of toxic organics.« less

Enhancement of surface area and wettability properties of boron doped diamond by femtosecond laser-induced periodic surface structuring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Granados, Eduardo; Calderon, Miguel Martinez; Krzywinski, Jacek

We demonstrate the formation of laser-induced periodic surface structures (LIPSS) in boron-doped diamond (BDD) by irradiation with femtosecond near-IR laser pulses. The results show that the obtained LIPSS are perpendicular to the laser polarization, and the ripple periodicity is on the order of half of the irradiation wavelength. The surface structures and their electrochemical properties were characterized using Raman micro-spectroscopy, in combination with scanning electron and atomic force microscopies. The textured BDD surface showed a dense and large surface area with no change in its structural characteristics. The effective surface area of the textured BDD electrode was approximately 50% largermore » than that of a planar substrate, while wetting tests showed that the irradiated area becomes highly hydrophilic. Lastly, our results indicate that LIPSS texturing of BDD is a straightforward and simple technique for enhancing the surface area and wettability properties of the BDD electrodes, which could enable higher current efficiency and lower energy consumption in the electrochemical oxidation of toxic organics.« less

XPS study of ruthenium tris-bipyridine electrografted from diazonium salt derivative on microcrystalline boron doped diamond.

PubMed

Agnès, Charles; Arnault, Jean-Charles; Omnès, Franck; Jousselme, Bruno; Billon, Martial; Bidan, Gérard; Mailley, Pascal

2009-12-28

Boron doped diamond (BDD) functionalization has received an increasing interest during the last few years. Such an infatuation comes from the original properties of BDD, including chemical stability or an electrochemical window, that opens the way for the design of (bio)sensors or smart interfaces. In such a context, diazonium salts appear to be well suited for BDD functionalization as they enable covalent immobilization of functional entities such as enzymes or DNA. In this study we report microcrystalline BDD functionalization with a metallic complex, ruthenium tris(bipyridine), using the p-(tris(bipyridine)Ru(2+))phenyl diazonium salt. Electrografting using cyclic voltammetry (CV) allowed the formation of a ruthenium complex film that was finely characterized using electrochemistry and X-ray photoelectron spectroscopy (XPS). Moreover, we showed that chronopotentiometry (CP) is a convenient tool to monitor Ru complex film deposition through the control of the electrochemical pulse parameters (i.e. current density and pulse duration). Finally, such a control was demonstrated through the correlation between electrochemical and XPS characterizations.

Synergetic antibacterial activity of reduced graphene oxide and boron doped diamond anode in three dimensional electrochemical oxidation system

PubMed Central

Qi, Xiujuan; Wang, Ting; Long, Yujiao; Ni, Jinren

2015-01-01

A 100% increment of antibacterial ability has been achieved due to significant synergic effects of boron-doped diamond (BDD) anode and reduced graphene oxide (rGO) coupled in a three dimensional electrochemical oxidation system. The rGO, greatly enhanced by BDD driven electric field, demonstrated strong antibacterial ability and even sustained its excellent performance during a reasonable period after complete power cut in the BDD-rGO system. Cell damage experiments and TEM observation confirmed much stronger membrane stress in the BDD-rGO system, due to the faster bacterial migration and charge transfer by the expanded electro field and current-carrying efficiency by quantum tunnel. Reciprocally the hydroxyl-radical production was eminently promoted with expanded area of electrodes and delayed recombination of the electron–hole pairs in presence of the rGO in the system. This implied a huge potential for practical disinfection with integration of the promising rGO and the advanced electrochemical oxidation systems. PMID:25994309

Biofouling resistance of boron-doped diamond neural stimulation electrodes is superior to titanium nitride electrodes in vivo.

PubMed

Meijs, S; Alcaide, M; Sørensen, C; McDonald, M; Sørensen, S; Rechendorff, K; Gerhardt, A; Nesladek, M; Rijkhoff, N J M; Pennisi, C P

2016-10-01

The goal of this study was to assess the electrochemical properties of boron-doped diamond (BDD) electrodes in relation to conventional titanium nitride (TiN) electrodes through in vitro and in vivo measurements. Electrochemical impedance spectroscopy, cyclic voltammetry and voltage transient (VT) measurements were performed in vitro after immersion in a 5% albumin solution and in vivo after subcutaneous implantation in rats for 6 weeks. In contrast to the TiN electrodes, the capacitance of the BDD electrodes was not significantly reduced in albumin solution. Furthermore, BDD electrodes displayed a decrease in the VTs and an increase in the pulsing capacitances immediately upon implantation, which remained stable throughout the whole implantation period, whereas the opposite was the case for the TiN electrodes. These results reveal that BDD electrodes possess a superior biofouling resistance, which provides significantly stable electrochemical properties both in protein solution as well as in vivo compared to TiN electrodes.

Preparation of glucose sensors using gold nanoparticles modified diamond electrode

NASA Astrophysics Data System (ADS)

Fachrurrazie; Ivandini, T. A.; Wibowo, W.

2017-04-01

A glucose sensor was successfully developed by immobilizing glucose oxidase (GOx) at boron-doped diamond (BDD) electrodes. Prior to GOx immobilization, the BDD was modified with gold nanoparticles (AuNPs). To immobilize AuNPs, the gold surface was modified to nitrogen termination. The characterization of the electrode surface was performed using an X-ray photoelectron spectroscopy and a scanning electron microscope, while the electrochemical properties of the enzyme electrode were characterized using cyclic voltammetry. Cyclic voltammograms of the prepared electrode for D-glucose in phosphate buffer solution pH 7 showed a new reduction peak at +0.16 V. The currents of the peak were linear in the concentration range of 0.1 M to 0.9 M, indicated that the GOx-AuNP-BDD can be applied for electrochemical glucose detection.

In vivo biocompatibility of boron doped and nitrogen included conductive-diamond for use in medical implants.

PubMed

Garrett, David J; Saunders, Alexia L; McGowan, Ceara; Specks, Joscha; Ganesan, Kumaravelu; Meffin, Hamish; Williams, Richard A; Nayagam, David A X

2016-01-01

Recently, there has been interest in investigating diamond as a material for use in biomedical implants. Diamond can be rendered electrically conducting by doping with boron or nitrogen. This has led to inclusion of boron doped and nitrogen included diamond elements as electrodes and/or feedthroughs for medical implants. As these conductive device elements are not encapsulated, there is a need to establish their clinical safety for use in implants. This article compares the biocompatibility of electrically conducting boron doped diamond (BDD) and nitrogen included diamond films and electrically insulating poly crystalline diamond films against a silicone negative control and a BDD sample treated with stannous octoate as a positive control. Samples were surgically implanted into the back muscle of a guinea pig for a period of 4-15 weeks, excised and the implant site sectioned and submitted for histological analysis. All forms of diamond exhibited a similar or lower thickness of fibrotic tissue encapsulating compared to the silicone negative control samples. All forms of diamond exhibited similar or lower levels of acute, chronic inflammatory, and foreign body responses compared to the silicone negative control indicating that the materials are well tolerated in vivo. © 2015 Wiley Periodicals, Inc.

Development of neuraminidase detection using gold nanoparticles boron-doped diamond electrodes.

PubMed

Wahyuni, Wulan T; Ivandini, Tribidasari A; Saepudin, Endang; Einaga, Yasuaki

2016-03-15

Gold nanoparticles-modified boron-doped diamond (AuNPs-BDD) electrodes, which were prepared with a self-assembly deposition of AuNPs at amine-terminated boron-doped diamond, were examined for voltammetric detection of neuraminidase (NA). The detection method was performed based on the difference of electrochemical responses of zanamivir at gold surface before and after the reaction with NA in phosphate buffer solution (PBS, pH 5.5). A linear calibration curve for zanamivir in 0.1 M PBS in the absence of NA was achieved in the concentration range of 1 × 10(-6) to 1 × 10(-5) M (R(2) = 0.99) with an estimated limit of detection (LOD) of 2.29 × 10(-6) M. Furthermore, using its reaction with 1.00 × 10(-5) M zanamivir, a linear calibration curve of NA can be obtained in the concentration range of 0-12 mU (R(2) = 0.99) with an estimated LOD of 0.12 mU. High reproducibility was shown with a relative standard deviation (RSD) of 1.14% (n = 30). These performances could be maintained when the detection was performed in mucin matrix. Comparison performed using gold-modified BDD (Au-BDD) electrodes suggested that the good performance of the detection method is due to the stability of the gold particles position at the BDD surface. Copyright © 2016 Elsevier Inc. All rights reserved.

Preparation of boron doped diamond modified by iridium for electroreduction of carbon dioxide (CO2)

NASA Astrophysics Data System (ADS)

Ichzan, A. M.; Gunlazuardi, J.; Ivandini, T. A.

2017-04-01

Electroreduction of carbon dioxide (CO2) at iridium oxide-modified boron-doped diamond (IrOx-BDD) electrodes in aqueous electrolytes was studied by voltammetric method. The aim of this study was to find out the catalytic effect of IrOx to produce fine chemicals contained of two or more carbon atoms (for example acetic acid) in high percentage. Characterization using FE-SEM and XPS indicated that IrO2 can be deposited at BDD electrode, whereas characterization using cyclic voltammetry indicated that the electrode was applicable to be used as working electrode for CO2 electroreduction.

Direct electrochemistry of Shewanella loihica PV-4 on gold nanoparticles-modified boron-doped diamond electrodes fabricated by layer-by-layer technique.

PubMed

Wu, Wenguo; Xie, Ronggang; Bai, Linling; Tang, Zuming; Gu, Zhongze

2012-05-01

Microbial Fuel Cells (MFCs) are robust devices capable of taping biological energy, converting pollutants into electricity through renewable biomass. The fabrication of nanostructured electrodes with good bio- and electrochemical activity, play a profound role in promoting power generation of MFCs. Au nanoparticles (AuNPs)-modified Boron-Doped Diamond (BDD) electrodes are fabricated by layer-by-layer (LBL) self-assembly technique and used for the direct electrochemistry of Shewanella loihica PV-4 in an electrochemical cell. Experimental results show that the peak current densities generated on the Au/PAH multilayer-modified BDD electrodes increased from 1.25 to 2.93 microA/cm(-2) as the layer increased from 0 to 6. Different cell morphologies of S. loihica PV-4 were also observed on the electrodes and the highest density of cells was attached on the (Au/PAH)6/BDD electrode with well-formed three-dimensional nanostructure. The electrochemistry of S. loihica PV-4 was enhanced on the (Au/PAH)4/BDD electrode due to the appropriate amount of AuNPsand thickness of PAH layer.

Electrochemical inactivation kinetics of boron-doped diamond electrode on waterborne pathogens.

PubMed

Yao, Yanyan; Kubota, Yoshinobu; Murakami, Taketoshi; Ochiai, Tsuyoshi; Ishiguro, Hitoshi; Nakata, Kazuya; Fujishima, Akira

2011-09-01

A boron-doped diamond (BDD) electrode was constructed as a water disinfector for the inactivation of water borne pathogens. The bactericidal effect of the disinfector was evaluated on artificially contaminated waters containing, respectively, Escherichia coli, Pseudomonas aeruginosa and Legionella pneumophila at high density. By treating the bacterial suspensions with 4 V of constant voltage between the BDD and the counter-electrode for 50 min, the population of E. coli and P. aeruginosa decreased from (10E + 7-8 colony-forming unit mL(-1)) to below the detection limits of the colony-formation method. Meanwhile, L. pneumophila were reduced to virtually zero when analyzed by fluorescence-based staining. The influences of production parameters (voltage, NaCl concentration and flow rate) on the disinfection kinetics of the BDD disinfector were examined with respect to operational conditions. Voltage was the most significant factor for adjusting the extent of electrolysis, followed by NaCl concentration and flow rate, to influence the disinfection efficiency. The disinfection of natural river water samples containing numerous microbes was performed for a practicability investigation of the BDD electrode. Approximately 99.99% bactericidal efficiency was confirmed by viability detection for E. coli and common germs in treated water. The results showed that the BDD electrode is a promising tool for various wastewater disinfections to combat waterborne diseases.

An All-Solid-State pH Sensor Employing Fluorine-Terminated Polycrystalline Boron-Doped Diamond as a pH-Insensitive Solution-Gate Field-Effect Transistor.

PubMed

Shintani, Yukihiro; Kobayashi, Mikinori; Kawarada, Hiroshi

2017-05-05

A fluorine-terminated polycrystalline boron-doped diamond surface is successfully employed as a pH-insensitive SGFET (solution-gate field-effect transistor) for an all-solid-state pH sensor. The fluorinated polycrystalline boron-doped diamond (BDD) channel possesses a pH-insensitivity of less than 3mV/pH compared with a pH-sensitive oxygenated channel. With differential FET (field-effect transistor) sensing, a sensitivity of 27 mv/pH was obtained in the pH range of 2-10; therefore, it demonstrated excellent performance for an all-solid-state pH sensor with a pH-sensitive oxygen-terminated polycrystalline BDD SGFET and a platinum quasi-reference electrode, respectively.

Screening metal nanoparticles using boron-doped diamond microelectrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivandini, Tribidasari A., E-mail: ivandini.tri@sci.ui.ac.id; Rangkuti, Prasmita K.; Einaga, Yasuaki

2016-04-19

Boron-doped diamond (BDD) microelectrodes were used to observe the correlation between electrocatalytic currents caused by individual Pt nanoparticle (Pt-np) collisions at the electrode. The BDD microelectrodes, ∼20 µm diameter and ∼2 µm particle size, were fabricated at the surface of tungsten wires. Pt-np with a size of 1 to 5 nm with agglomerations up to 20 nm was used for observation. The electrolytic currents were observed via catalytic reaction of 15 mM hydrazine in 50 mM phosphate buffer solution at Pt-np at 0.4 V when it collides with the surface of the microelectrodes. The low current noise and wider potential window in the measurements using BDD microelectrodemore » produced a better results, which represents a better correlation to the TEM result of the Pt-np, compared to when gold microelectrodes was used.« less

Degradation of creatinine using boron-doped diamond electrode: Statistical modeling and degradation mechanism.

PubMed

Zhang, Zhefeng; Xian, Jiahui; Zhang, Chunyong; Fu, Degang

2017-09-01

This study investigated the degradation performance and mechanism of creatinine (a urine metabolite) with boron-doped diamond (BDD) anodes. Experiments were performed using a synthetic creatinine solution containing two supporting electrolytes (NaCl and Na 2 SO 4 ). A three-level central composite design was adopted to optimize the degradation process, a mathematical model was thus constructed and used to explore the optimum operating conditions. A maximum mineralization percentage of 80% following with full creatinine removal had been achieved within 120 min of electrolysis, confirming the strong oxidation capability of BDD anodes. Moreover, the results obtained suggested that supporting electrolyte concentration should be listed as one of the most important parameters in BDD technology. Lastly, based on the results from quantum chemistry calculations and LC/MS analyses, two different reaction pathways which governed the electrocatalytic oxidation of creatinine irrespective of the supporting electrolytes were identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

Electrochemical incineration of indigo. A comparative study between 2D (plate) and 3D (mesh) BDD anodes fitted into a filter-press reactor.

PubMed

Nava, José L; Sirés, Ignasi; Brillas, Enric

2014-01-01

This paper compares the performance of 2D (plate) and 3D (mesh) boron-doped diamond (BDD) electrodes, fitted into a filter-press reactor, during the electrochemical incineration of indigo textile dye as a model organic compound in chloride medium. The electrolyses were carried out in the FM01-LC reactor at mean fluid velocities between 0.9 ≤ u ≤ 10.4 and 1.2 ≤ u ≤ 13.9 cm s(-1) for the 2D BDD and the 3D BDD electrodes, respectively, at current densities of 5.63 and 15 mA cm(-2). The oxidation of the organic matter was promoted, on the one hand, via the physisorbed hydroxyl radicals (BDD(·OH)) formed from water oxidation at the BDD surface and, on the other hand, via active chlorine formed from the oxidation of chloride ions on BDD. The performance of 2D BDD and 3D BDD electrodes in terms of current efficiency, energy consumption, and charge passage during the treatments is discussed.

Effect of boron doping on first-order Raman scattering in superconducting boron doped diamond films

NASA Astrophysics Data System (ADS)

Kumar, Dinesh; Chandran, Maneesh; Ramachandra Rao, M. S.

2017-05-01

Aggregation of impurity levels into an impurity band in heavily boron doped diamond results in a background continuum and discrete zone centre phonon interference during the inelastic light scattering process. In order to understand the Raman scattering effect in granular BDD films, systematically heavily doped samples in the semiconducting and superconducting regimes have been studied using the excitation wavelengths in the UV and visible regions. A comprehensive analysis of the Fano resonance effect as a function of the impurity concentrations and the excitation frequencies is presented. Various Raman modes available in BDD including signals from the grain boundaries are discussed.

Elastic and mechanical softening in boron-doped diamond

PubMed Central

Liu, Xiaobing; Chang, Yun-Yuan; Tkachev, Sergey N.; Bina, Craig R.; Jacobsen, Steven D.

2017-01-01

Alternative approaches to evaluating the hardness and elastic properties of materials exhibiting physical properties comparable to pure diamond have recently become necessary. The classic linear relationship between shear modulus (G) and Vickers hardness (HV), along with more recent non-linear formulations based on Pugh’s modulus extending into the superhard region (HV > 40 GPa) have guided synthesis and identification of novel superabrasives. These schemes rely on accurately quantifying HV of diamond-like materials approaching or potentially exceeding the hardness of the diamond indenter, leading to debate about methodology and the very definition of hardness. Elasticity measurements on such materials are equally challenging. Here we used a high-precision, GHz-ultrasonic interferometer in conjunction with a newly developed optical contact micrometer and 3D optical microscopy of indentations to evaluate elasticity-hardness relations in the ultrahard range (HV > 80 GPa) by examining single-crystal boron-doped diamond (BDD) with boron contents ranging from 50–3000 ppm. We observe a drastic elastic-mechanical softening in highly doped BDD relative to the trends observed for superhard materials, providing insight into elasticity-hardness relations for ultrahard materials. PMID:28233808

Elastic and mechanical softening in boron-doped diamond

NASA Astrophysics Data System (ADS)

Liu, Xiaobing; Chang, Yun-Yuan; Tkachev, Sergey N.; Bina, Craig R.; Jacobsen, Steven D.

2017-02-01

Alternative approaches to evaluating the hardness and elastic properties of materials exhibiting physical properties comparable to pure diamond have recently become necessary. The classic linear relationship between shear modulus (G) and Vickers hardness (HV), along with more recent non-linear formulations based on Pugh’s modulus extending into the superhard region (HV > 40 GPa) have guided synthesis and identification of novel superabrasives. These schemes rely on accurately quantifying HV of diamond-like materials approaching or potentially exceeding the hardness of the diamond indenter, leading to debate about methodology and the very definition of hardness. Elasticity measurements on such materials are equally challenging. Here we used a high-precision, GHz-ultrasonic interferometer in conjunction with a newly developed optical contact micrometer and 3D optical microscopy of indentations to evaluate elasticity-hardness relations in the ultrahard range (HV > 80 GPa) by examining single-crystal boron-doped diamond (BDD) with boron contents ranging from 50-3000 ppm. We observe a drastic elastic-mechanical softening in highly doped BDD relative to the trends observed for superhard materials, providing insight into elasticity-hardness relations for ultrahard materials.

Electrochemical incineration of diclofenac in neutral aqueous medium by anodic oxidation using Pt and boron-doped diamond anodes.

PubMed

Brillas, Enric; Garcia-Segura, Sergi; Skoumal, Marcel; Arias, Conchita

2010-04-01

The degradation of diclofenac, a common non-steroidal anti-inflammatory drug, in aqueous medium has been studied by anodic oxidation (AO) using an undivided cell with a Pt or boron-doped diamond (BDD) anode. Operating without pH regulation, AO with Pt acidifies the solution with precipitation of its protonated form, whereas using BDD, the solution becomes alkaline and only attains partial mineralization. Total incineration of low contents of the drug is feasible by AO with BDD in a neutral buffer medium of pH 6.5. Comparative treatment with Pt gives poor decontamination. The diclofenac decay always follows a pseudo first-order reaction. The increase in current for AO with BDD accelerates the degradative process, but decreases its efficiency. 2-Hydroxyphenylacetic acid, 2,5-dihydroxyphenylacetic acid, 2,6-dichloroaniline and 2,6-dichlorohydroquinone have been identified as aromatic intermediates. For AO with Pt, high amounts of malic, succinic, tartaric and oxalic acids are accumulated in the bulk and the N-derivatives produced are rapidly destroyed with loss of NH4+. When BDD is employed, some carboxylic acids are also accumulated in small extent, with a larger persistence of oxalic and oxamic acids. The process involves the formation of different N-derivatives that slowly release NH4+ and NO3(-) ions. Chloride ion is lost in all cases. 2010 Elsevier Ltd. All rights reserved.

Comparing atrazine and cyanuric acid electro-oxidation on mixed oxide and boron-doped diamond electrodes.

PubMed

Malpass, Geoffroy R P; Salazar-Banda, Giancarlo R; Miwa, Douglas W; Machado, Sérgio A S; Motheo, Artur J

2013-01-01

The breakdown of pesticides has been promoted by many methods for clean up of contaminated soil and wastewaters. The main goal is to decrease the toxicity of the parent compound to achieve non-toxic compounds or even, when complete mineralization occurs, carbon dioxide and water. Therefore, electrochemical degradation (potentiostatic and galvanostatic) of both the pesticide atrazine and cyanuric acid (CA) at boron-doped diamond (BDD) and Ti/Ru0.3Ti0.7O2 dimensionally stable anode (DSA) electrodes, in different supporting electrolytes (NaCl and Na2SO4), is presented with the aim of establishing the influence of the operational parameters on the process efficiency. The results demonstrate that both the electrode material and the supporting electrolyte have a strong influence on the rate of atrazine removal. In the chloride medium, the rate of atrazine removal is always greater than in sulfate under all conditions employed. Furthermore, in the sulfate medium, atrazine degradation was significant only at the BDD electrode. The total organic carbon (TOC) load decreased by 79% and 56% at the BDD and DSA electrodes, respectively, in the chloride medium. This trend was maintained in the sulfate medium but the TOC removal was lower (i.e. 33% and 13% at BDD and DSA electrodes, respectively). CA, a stable atrazine degradation intermediate, was also studied and it is efficiently removed using the BDD electrode in both media, mainly when high current densities are employed. The use of the BDD electrode in the chloride medium not only degrades atrazine but also mineralized cyanuric acid leading to the higher TOC removal.

Destination of organic pollutants during electrochemical oxidation of biologically-pretreated dye wastewater using boron-doped diamond anode.

PubMed

Zhu, Xiuping; Ni, Jinren; Wei, Junjun; Xing, Xuan; Li, Hongna

2011-05-15

Electrochemical oxidation of biologically-pretreated dye wastewater was performed in a boron-doped diamond (BDD) anode system. After electrolysis of 12h, the COD was decreased from 532 to 99 mg L(-1) (<100 mg L(-1), the National Discharge Standard of China). More importantly, the destination of organic pollutants during electrochemical oxidation process was carefully investigated by molecular weight distribution measurement, resin fractionation, ultraviolet-visible spectroscopy, HPLC and GC-MS analysis, and toxicity test. As results, most organic pollutants were completely removed by electrochemical oxidation and the rest was primarily degraded to simpler compounds (e.g., carboxylic acids and short-chain alkanes) with less toxicity, which demonstrated that electrochemical oxidation of biologically-pretreated dye wastewater with BDD anode was very effective and safe. Especially, the performance of BDD anode system in degradation of large molecular organics such as humic substances makes it very promising in practical applications as an advanced treatment of biologically-pretreated wastewaters. Copyright © 2011 Elsevier B.V. All rights reserved.

Domestic and Industrial Water Disinfection Using Boron-Doped Diamond Electrodes

NASA Astrophysics Data System (ADS)

Rychen, Philippe; Provent, Christophe; Pupunat, Laurent; Hermant, Nicolas

This chapter first describes main properties and manufacturing process (production using HF-CVD, quality-control measurements, etc.) of diamond electrodes and more specifically boron-doped diamond (BDD) electrodes. Their exceptional properties make such electrodes particularly suited for many disinfection applications as thanks to their wide working potential window and their high anodic potential, they allow generating a mixture of powerful oxidizing species mainly based on active oxygen and peroxides. Such mixture of disinfecting agents is far more efficient than conventional chemical or physical known techniques. Their efficiency was tested against numerous microorganisms and then proved to be greater than conventional methods. All bacteria and viruses tested up to date were inactivated 3-5 times faster with a treatment based on with BDD electrodes and the DiaCellⓇ technology than with other techniques. Several applications, either industrial or private (wellness and home use), are discussed with a focus on the dedicated products and the main technology advantages.

The contribution of mediated oxidation mechanisms in the electrolytic degradation of cyanuric acid using diamond anodes.

PubMed

Bensalah, Nasr; Dbira, Sondos; Bedoui, Ahmed

2016-07-01

In this work, the contribution of mediated oxidation mechanisms in the electrolytic degradation of cyanuric acid using boron-doped diamond (BDD) anodes was investigated in different electrolytes. A complete mineralization of cyanuric acid was obtained in NaCl; however lower degrees of mineralization of 70% and 40% were obtained in Na2SO4 and NaClO4, respectively. This can be explained by the nature of the oxidants electrogenerated in each electrolyte. It is clear that the contribution of active chlorine (Cl2, HClO, ClO(-)) electrogenerated from oxidation of chlorides on BDD is much more important in the electrolytic degradation of cyanuric acid than the persulfate and hydroxyl radicals produced by electro-oxidation of sulfate and water on BDD anodes. This could be explained by the high affinity of active chlorine towards nitrogen compounds. No organic intermediates were detected during the electrolytic degradation of cyanuric acid in any the electrolytes, which can be explained by their immediate depletion by hydroxyl radicals produced on the BDD surface. Nitrates and ammonium were the final products of electrolytic degradation of cyanuric acid on BDD anodes in all electrolytes. In addition, small amounts of chloramines were formed in the chloride medium. Low current density (≤10mA/cm(2)) and neutral medium (pH in the range 6-9) should be used for high efficiency electrolytic degradation and negligible formation of hazardous chlorate and perchlorate. Copyright © 2016. Published by Elsevier B.V.

Highly sensitive detection of influenza virus by boron-doped diamond electrode terminated with sialic acid-mimic peptide.

PubMed

Matsubara, Teruhiko; Ujie, Michiko; Yamamoto, Takashi; Akahori, Miku; Einaga, Yasuaki; Sato, Toshinori

2016-08-09

The progression of influenza varies according to age and the presence of an underlying disease; appropriate treatment is therefore required to prevent severe disease. Anti-influenza therapy, such as with neuraminidase inhibitors, is effective, but diagnosis at an early phase of infection before viral propagation is critical. Here, we show that several dozen plaque-forming units (pfu) of influenza virus (IFV) can be detected using a boron-doped diamond (BDD) electrode terminated with a sialic acid-mimic peptide. The peptide was used instead of the sialyloligosaccharide receptor, which is the common receptor of influenza A and B viruses required during the early phase of infection, to capture IFV particles. The peptide, which was previously identified by phage-display technology, was immobilized by click chemistry on the BDD electrode, which has excellent electrochemical characteristics such as low background current and weak adsorption of biomolecules. Electrochemical impedance spectroscopy revealed that H1N1 and H3N2 IFVs were detectable in the range of 20-500 pfu by using the peptide-terminated BDD electrode. Our results demonstrate that the BDD device integrated with the receptor-mimic peptide has high sensitivity for detection of a low number of virus particles in the early phase of infection.

A novel electroless method to prepare a platinum electrocatalyst on diamond for fuel cell applications

NASA Astrophysics Data System (ADS)

Lyu, Xiao; Hu, Jingping; Foord, John S.; Wang, Qiang

2013-11-01

A novel electroless deposition method was demonstrated to prepare a platinum electrocatalyst on boron doped diamond (BDD) substrates without the need for pre-activation. This green method addresses the uniformity and particle size issues associated with electrodeposition and circumvents the pre-activation procedure which is necessary for conventional electroless deposition. The inert BDD substrate formed a galvanic couple with an iron wire, to overcome the activation barrier associated with conventional electroless deposition on diamond, leading to the formation of Pt nanoparticles on the electrode surface in a galvanic process coupled to a chemical process. When sodium hypophosphite was employed as the reducing agent to drive the electroless reaction Pt deposits which were contaminated with iron and phosphorus resulted. In contrast, the reducing agent ascorbic acid gave rise to high purity Pt nanoparticles. Optimal deposition conditions with respect to bath temperature, pH value and stabilizing additives are identified. Using this approach, high purity and uniformly distributed platinum nanoparticles are obtained on the diamond electrode surface, which demonstrate a high electrochemical activity towards methanol oxidation.

Boron doped diamond synthesized from detonation nanodiamond in a C-O-H fluid at high pressure and high temperature

NASA Astrophysics Data System (ADS)

Shakhov, Fedor M.; Abyzov, Andrey M.; Takai, Kazuyuki

2017-12-01

Boron doped diamond (BDD) was synthesized under high pressure and high temperature (HPHT) of 7 GPa, 1230 °C in a short time of 10 s from a powder mixtures of detonation nanodiamond (DND), pentaerythritol C5H8(OH)4 and amorphous boron. SEM, TEM, XRD, XPS, FTIR and Raman spectroscopy indicated that BDD nano- and micro-crystals have formed by consolidation of DND particles (4 nm in size). XRD showed the enlargement of crystallites size to 6-80 nm and the increase in diamond lattice parameter by 0.02-0.07% without appearance of any microstrains. Raman spectroscopy was used to estimate the content of boron atoms embedded in the diamond lattice. It was found that the Raman diamond peak shifts significantly from 1332 cm-1 to 1290 cm-1 without appearance of any non-diamond carbon. The correlation between Raman peak position, its width, and boron content in diamond is proposed. Hydrogenated diamond carbon in significant amount was detected by IR spectroscopy and XPS. Due to the doping with boron content of about 0.1 at%, the electrical conductivity of the diamond achieved approximately 0.2 Ω-1 cm-1. Reaction mechanism of diamond growth (models of recrystallization and oriented attachment) is discussed, including the initial stages of pentaerythritol pyrolysis and thermal desorption of functional groups from the surface of DND particles with the generation of supercritical fluid of low-molecular substances (H2O, CH4, CO, CO2, etc.), as well as byproducts formation (B2O3, B4C).

Boron doped diamond sensor for sensitive determination of metronidazole: Mechanistic and analytical study by cyclic voltammetry and square wave voltammetry.

PubMed

Ammar, Hafedh Belhadj; Brahim, Mabrouk Ben; Abdelhédi, Ridha; Samet, Youssef

2016-02-01

The performance of boron-doped diamond (BDD) electrode for the detection of metronidazole (MTZ) as the most important drug of the group of 5-nitroimidazole was proven using cyclic voltammetry (CV) and square wave voltammetry (SWV) techniques. A comparison study between BDD, glassy carbon and silver electrodes on the electrochemical response was carried out. The process is pH-dependent. In neutral and alkaline media, one irreversible reduction peak related to the hydroxylamine derivative formation was registered, involving a total of four electrons. In acidic medium, a prepeak appears probably related to the adsorption affinity of hydroxylamine at the electrode surface. The BDD electrode showed higher sensitivity and reproducibility analytical response, compared with the other electrodes. The higher reduction peak current was registered at pH11. Under optimal conditions, a linear analytical curve was obtained for the MTZ concentration in the range of 0.2-4.2μmolL(-1), with a detection limit of 0.065μmolL(-1). Copyright © 2015 Elsevier B.V. All rights reserved.

Multichannel Boron Doped Nanocrystalline Diamond Ultramicroelectrode Arrays: Design, Fabrication and Characterization

PubMed Central

Kiran, Raphael; Rousseau, Lionel; Lissorgues, Gaëlle; Scorsone, Emmanuel; Bongrain, Alexandre; Yvert, Blaise; Picaud, Serge; Mailley, Pascal; Bergonzo, Philippe

2012-01-01

We report on the fabrication and characterization of an 8 × 8 multichannel Boron Doped Diamond (BDD) ultramicro-electrode array (UMEA). The device combines both the assets of microelectrodes, resulting from conditions in mass transport from the bulk solution toward the electrode, and of BDD's remarkable intrinsic electrochemical properties. The UMEAs were fabricated using an original approach relying on the selective growth of diamond over pre-processed 4 inches silicon substrates. The prepared UMEAs were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results demonstrated that the electrodes have exhibited a very fast electrode transfer rate (k0) up to 0.05 cm·s−1 (in a fast redox couple) and on average, a steady state limiting current (in a 0.5 M potassium chloride aqueous solution containing 1 mM Fe(CN)64− ion at 100 mV·s−1) of 1.8 nA. The UMEAs are targeted for electrophysiological as well as analytical applications. PMID:22969367

Boron-doped diamond synthesized at high-pressure and high-temperature with metal catalyst

NASA Astrophysics Data System (ADS)

Shakhov, Fedor M.; Abyzov, Andrey M.; Kidalov, Sergey V.; Krasilin, Andrei A.; Lähderanta, Erkki; Lebedev, Vasiliy T.; Shamshur, Dmitriy V.; Takai, Kazuyuki

2017-04-01

The boron-doped diamond (BDD) powder consisting of 40-100 μm particles was synthesized at 5 GPa and 1500-1600 °C from a mixture of 50 wt% graphite and 50 wt% Ni-Mn catalyst with an addition of 1 wt% or 5 wt% boron powder. The size of crystal domains of doped and non-doped diamond was evaluated as a coherent scattering region by X-ray diffraction (XRD) and using small-angle neutron scattering (SANS), being ≥180 nm (XRD) and 100 nm (SANS). Magnetic impurities of NiMnx originating from the catalyst in the synthesis, which prevent superconductivity, were detected by magnetization measurements at 2-300 K. X-ray photoelectron spectroscopy, the temperature dependence of the resistivity, XRD, and Raman spectroscopy reveal that the concentration of electrically active boron is as high as (2±1)×1020 cm-3 (0.1 at%). To the best of our knowledge, this is the highest boron content for BDD synthesized in high-pressure high-temperature process with metal catalysts.

3D-nanostructured boron-doped diamond for microelectrode array neural interfacing.

PubMed

Piret, Gaëlle; Hébert, Clément; Mazellier, Jean-Paul; Rousseau, Lionel; Scorsone, Emmanuel; Cottance, Myline; Lissorgues, Gaelle; Heuschkel, Marc O; Picaud, Serge; Bergonzo, Philippe; Yvert, Blaise

2015-06-01

The electrode material is a key element in the design of long-term neural implants and neuroprostheses. To date, the ideal electrode material offering high longevity, biocompatibility, low-noise recording and high stimulation capabilities remains to be found. We show that 3D-nanostructured boron doped diamond (BDD), an innovative material consisting in a chemically stable material with a high aspect ratio structure obtained by encapsulation of a carbon nanotube template within two BDD nanolayers, allows neural cell attachment, survival and neurite extension. Further, we developed arrays of 20-μm-diameter 3D-nanostructured BDD microelectrodes for neural interfacing. These microelectrodes exhibited low impedances and low intrinsic recording noise levels. In particular, they allowed the detection of low amplitude (10-20 μV) local-field potentials, single units and multiunit bursts neural activity in both acute whole embryonic hindbrain-spinal cord preparations and long-term hippocampal cell cultures. Also, cyclic voltammetry measurements showed a wide potential window of about 3 V and a charge storage capacity of 10 mC.cm(-2), showing high potentiality of this material for neural stimulation. These results demonstrate the attractiveness of 3D-nanostructured BDD as a novel material for neural interfacing, with potential applications for the design of biocompatible neural implants for the exploration and rehabilitation of the nervous system. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Oxidation of carbon monoxide, hydrogen peroxide and water at a boron doped diamond electrode: the competition for hydroxyl radicals.

PubMed

Kisacik, Izzet; Stefanova, Ana; Ernst, Siegfried; Baltruschat, Helmut

2013-04-07

Boron doped diamond (BDD) electrodes have an extremely high over-voltage for oxygen evolution from water, which favours its use in oxidation processes of other compounds at high potentials. We used a rotating ring disc (RRDE) assembly and differential electrochemical mass spectrometry (DEMS) in order to monitor the consumption or the production of species in the course of the electrode processes. By intercepting the intermediate of the electrochemical water oxidation with chemical reactions we demonstrate clearly, albeit indirectly, that in the water oxidation process at BDD above 2.5 V the first step is the formation of ˙OH radicals. The electro-oxidation of CO to CO2 at BDD electrodes proceeds only via a first attack by ˙OH radicals followed by a further electron transfer to the electrode. At potentials below the onset of oxygen evolution from water, H2O2 is oxidised by a direct electron transfer to the BDD electrode, while at higher potentials, two different reactions paths compete for the ˙OH radicals formed in the first electron transfer from water: one, where these ˙OH radicals react with each other followed by further electron transfers leading to O2 on the one hand and one, where ˙OH radicals react with other species like H2O2 or CO with subsequent electron transfers on the other hand.

Diamond nanowires: a novel platform for electrochemistry and matrix-free mass spectrometry.

PubMed

Szunerits, Sabine; Coffinier, Yannick; Boukherroub, Rabah

2015-05-27

Over the last decades, carbon-based nanostructures have generated a huge interest from both fundamental and technological viewpoints owing to their physicochemical characteristics, markedly different from their corresponding bulk states. Among these nanostructured materials, carbon nanotubes (CNTs), and more recently graphene and its derivatives, hold a central position. The large amount of work devoted to these materials is driven not only by their unique mechanical and electrical properties, but also by the advances made in synthetic methods to produce these materials in large quantities with reasonably controllable morphologies. While much less studied than CNTs and graphene, diamond nanowires, the diamond analogue of CNTs, hold promise for several important applications. Diamond nanowires display several advantages such as chemical inertness, high mechanical strength, high thermal and electrical conductivity, together with proven biocompatibility and existence of various strategies to functionalize their surface. The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications. In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces. The first part of the present review article will cover the promising applications of BDD NWS for label-free sensing. Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed.

Diamond Nanowires: A Novel Platform for Electrochemistry and Matrix-Free Mass Spectrometry

PubMed Central

Szunerits, Sabine; Coffinier, Yannick; Boukherroub, Rabah

2015-01-01

Over the last decades, carbon-based nanostructures have generated a huge interest from both fundamental and technological viewpoints owing to their physicochemical characteristics, markedly different from their corresponding bulk states. Among these nanostructured materials, carbon nanotubes (CNTs), and more recently graphene and its derivatives, hold a central position. The large amount of work devoted to these materials is driven not only by their unique mechanical and electrical properties, but also by the advances made in synthetic methods to produce these materials in large quantities with reasonably controllable morphologies. While much less studied than CNTs and graphene, diamond nanowires, the diamond analogue of CNTs, hold promise for several important applications. Diamond nanowires display several advantages such as chemical inertness, high mechanical strength, high thermal and electrical conductivity, together with proven biocompatibility and existence of various strategies to functionalize their surface. The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications. In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces. The first part of the present review article will cover the promising applications of BDD NWS for label-free sensing. Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed. PMID:26024422

Bimetallic Pt-Au nanocatalysts electrochemically deposited on boron-doped diamond electrodes for nonenzymatic glucose detection.

PubMed

Nantaphol, Siriwan; Watanabe, Takeshi; Nomura, Naohiro; Siangproh, Weena; Chailapakul, Orawon; Einaga, Yasuaki

2017-12-15

The enormous demand for medical diagnostics has encouraged the fabrication of high- performance sensing platforms for the detection of glucose. Nonenzymatic glucose sensors are coming ever closer to being used in practical applications. Bimetallic catalysts have been shown to be superior to single metal catalysts in that they have greater activity and selectivity. Here, we demonstrate the preparation, characterization, and electrocatalytic characteristics of a new bimetallic Pt/Au nanocatalyst. This nanocatalyst can easily be synthesized by electrodeposition by sequentially depositing Au and Pt on the surface of a boron-doped diamond (BDD) electrode. We characterized the nanocatalyst by scanning electron microscopy (SEM), X-ray diffraction (XRD), and voltammetry. The morphology and composition of the nanocatalyst can be easily controlled by adjusting the electrodeposition process and the molar ratio between the Pt and Au precursors. The electrocatalytic characteristics of a Pt/Au/BDD electrode for the nonenzymatic oxidation of glucose were systematically investigated by cyclic voltammetry. The electrode exhibits higher catalytic activity for glucose oxidation than Pt/BDD and Au/BDD electrodes. The best catalytic activity and stability was obtained with a Pt:Au molar ratio of 50:50. Moreover, the presence of Au can significantly enhance the long-term stability and poisoning tolerance during the electro-oxidation of glucose. Measurements of glucose using the Pt/Au/BDD electrode were linear in the range from 0.01 to 7.5mM, with a detection limit of 0.0077mM glucose. The proposed electrode performs selective electrochemical analysis of glucose in the presence of common interfering species (e.g., acetaminophen, uric and ascorbic acids), avoiding the generation of overlapping signals from such species. Copyright © 2017 Elsevier B.V. All rights reserved.

Mechanism of Enhanced Electrochemical Oxidation of 2,4-dichlorophenoxyacetic Acid with in situ Microwave Activated Boron-doped Diamond and Platinum Anodes

NASA Astrophysics Data System (ADS)

Gao, Junxia; Zhao, Guohua; Liu, Meichuan; Li, Dongming

2009-09-01

Remarkable enhancement in degradation effect is achieved at in situ activated boron-doped diamond (BDD) and Pt anodes with different extent through electrochemical oxidation (EC) of 2,4-dichlorophenoxyacetic acid (2,4-D) with microwave (MW) radiation in a flow system. Results show that when EC is activated with MW radiation, the complete mineralization time of 2,4-D at the BDD is reduced quickly from 10 to 4 h while Chemical oxygen demand (COD) removal at Pt is increased from 37.7 to 58.3% at 10 h; the initial current efficiency is both improved about 1.5 times while the pseudo-first-order rate constant is increased by 153 and 119% at the BDD and Pt, respectively. To gain insight into the higher efficiency in microwave activated EC, the mechanism has therefore been systematically evaluated from the essence of electrochemical reaction and the accumulated hydroxyl radical concentration. 2,4-Dichlorophenol, catechol, benquinone, and maleic and oxalic acids are the main intermediates on the Pt anode measured by high performance liquid chromatography (HPLC), while the intermediates on the BDD electrode include 2,4-dichlorophenol, hydroquinone, and maleic and oxalic acids. The reaction pathway with microwave radiation is the same as that in a conventional electrochemical oxidation on both electrodes. While less and lower aromatic intermediates produce at the BDD with MW, which suggests the higher ring-open ratio and the faster oxidation of carboxylic acids. With microwave radiation, the ring-open ratio at the BDD is increased to 98.8% from 85.6%; the value at Pt is increased to 67.3% from 35.9%. So microwave radiation can activate the electrochemical oxidation, which leads to the higher efficiency. This promotion is mainly due to the higher accumulated hydroxyl radical concentration and the effects by microwave radiation. All the results prove that the BDD electrode presents much better mineralization performance with MW. To the best of our knowledge, it is the first time the systematic analysis of the mechanism of microwave activated EC has been reported.

Electrochemical oxidation of nitrogen-heterocyclic compounds at boron-doped diamond electrode.

PubMed

Xing, Xuan; Zhu, Xiuping; Li, Hongna; Jiang, Yi; Ni, Jinren

2012-01-01

Nitrogen-heterocyclic compounds (NHCs) are toxic and bio-refractory contaminants widely spread in environment. This study investigated electrochemical degradation of NHCs at boron-doped diamond (BDD) anode with particular attention to the effect of different number and position of nitrogen atoms in molecular structure. Five classical NHCs with similar structures including indole (ID), quinoline (QL), isoquinoline (IQL), benzotriazole (BT) and benzimidazole (BM) were selected as the target compounds. Results of bulk electrolysis showed that degradation of all NHCs was fit to a pseudo first-order equation. The five compounds were degraded with the following sequence: ID>QL>IQL>BT>BM in terms of their rates of oxidation. Quantum chemical calculation was combined with experimental results to describe the degradation character of NHCs at BDD anode. A linear relationship between degradation rate and delocalization energy was observed, which demonstrated that electronic charge was redistributed through the conjugation system and accumulated at the active sites under the attack of hydroxyl radicals produced at BDD anode. Moreover, atom charge was calculated by semi empirical PM3 method and active sites of NHCs were identified respectively. Analysis of intermediates by GC-MS showed agreement with calculation results. Copyright © 2011 Elsevier Ltd. All rights reserved.

Removal of oxyfluorfen from ex-situ soil washing fluids using electrolysis with diamond anodes.

PubMed

dos Santos, Elisama Vieira; Sáez, Cristina; Martínez-Huitle, Carlos Alberto; Cañizares, Pablo; Rodrigo, Manuel Andres

2016-04-15

In this research, firstly, the treatment of soil spiked with oxyfluorfen was studied using a surfactant-aided soil-washing (SASW) process. After that, the electrochemical treatment of the washing liquid using boron doped diamond (BDD) anodes was performed. Results clearly demonstrate that SASW is a very efficient approach in the treatment of soil, removing the pesticide completely by using dosages below 5 g of sodium dodecyl sulfate (SDS) per Kg of soil. After that, complete mineralization of organic matter (oxyflourfen, SDS and by-products) was attained (100% of total organic carbon and chemical oxygen demand removals) when the washing liquids were electrolyzed using BDD anodes, but the removal rate depends on the size of the particles in solution. Electrolysis of soil washing fluids occurs via the reduction in size of micelles until their complete depletion. Lower concentrations of intermediates are produced (sulfate, chlorine, 4-(trifluoromethyl)-phenol and ortho-nitrophenol) during BDD-electrolyzes. Finally, it is important to indicate that, sulfate (coming from SDS) and chlorine (coming from oxyfluorfen) ions play an important role during the electrochemical organic matter removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diamond-based electrochemical aptasensor realizing a femtomolar detection limit of bisphenol A.

PubMed

Ma, Yibo; Liu, Junsong; Li, Hongdong

2017-06-15

In this study, we designed and fabricated an electrochemical impedance aptasensor based on Au nanoparticles (Au-NPs) coated boron-doped diamond (BDD) modified with aptamers, and 6-mercapto-1-hexanol (MCH) for the detection of bisphenol A (BPA). The constructed BPA aptasensor exhibits good linearity from 1.0×10 -14 to 1.0×10 -9 molL -1 . The detection limitation of 7.2×10 -15 molL -1 was achieved, which can be attributed to the synergistic effect of combining BDD with Au-NPs, aptamers, and MCH. The examine results of BPA traces in Tris-HCl buffer and in milk, UV spectra of aptamer/BPA and interference test revealed that the novel aptasensors are of high sensitivity, specificity, stability and repeatability, which could be promising in practical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Simultaneous detection of iodine and iodide on boron doped diamond electrodes.

PubMed

Fierro, Stéphane; Comninellis, Christos; Einaga, Yasuaki

2013-01-15

Individual and simultaneous electrochemical detection of iodide and iodine has been performed via cyclic voltammetry on boron doped diamond (BDD) electrodes in a 1M NaClO(4) (pH 8) solution, representative of typical environmental water conditions. It is feasible to compute accurate calibration curve for both compounds using cyclic voltammetry measurements by determining the peak current intensities as a function of the concentration. A lower detection limit of about 20 μM was obtained for iodide and 10 μM for iodine. Based on the comparison between the peak current intensities reported during the oxidation of KI, it is probable that iodide (I(-)) is first oxidized in a single step to yield iodine (I(2)). The latter is further oxidized to obtain IO(3)(-). This technique, however, did not allow for a reasonably accurate detection of iodate (IO(3)(-)) on a BDD electrode. Copyright © 2012 Elsevier B.V. All rights reserved.

Application of electrochemical technology for removing petroleum hydrocarbons from produced water using lead dioxide and boron-doped diamond electrodes.

PubMed

Gargouri, Boutheina; Gargouri, Olfa Dridi; Gargouri, Bochra; Trabelsi, Souhel Kallel; Abdelhedi, Ridha; Bouaziz, Mohamed

2014-12-01

Although diverse methods exist for treating polluted water, the most promising and innovating technology is the electrochemical remediation process. This paper presents the anodic oxidation of real produced water (PW), generated by the petroleum exploration of the Petrobras plant-Tunisia. Experiments were conducted at different current densities (30, 50 and 100 mA cm(-2)) using the lead dioxide supported on tantalum (Ta/PbO2) and boron-doped diamond (BDD) anodes in an electrolytic batch cell. The electrolytic process was monitored by the chemical oxygen demand (COD) and the residual total petroleum hydrocarbon [TPH] in order to know the feasibility of electrochemical treatment. The characterization and quantification of petroleum wastewater components were performed by gas chromatography mass spectrometry. The COD removal was approximately 85% and 96% using PbO2 and BDD reached after 11 and 7h, respectively. Compared with PbO2, the BDD anode showed a better performance to remove petroleum hydrocarbons compounds from produced water. It provided a higher oxidation rate and it consumed lower energy. However, the energy consumption and process time make useless anodic oxidation for the complete elimination of pollutants from PW. Cytotoxicity has shown that electrochemical oxidation using BDD could be efficiently used to reduce more than 90% of hydrocarbons compounds. All results suggest that electrochemical oxidation could be an effective approach to treat highly concentrated organic pollutants present in the industrial petrochemical wastewater and significantly reduce the cost and time of treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Selective Electrocatalytic Degradation of Odorous Mercaptans Derived from S-Au Bond Recongnition on a Dendritic Gold/Boron-Doped Diamond Composite Electrode.

PubMed

Chai, Shouning; Wang, Yujing; Zhang, Ya-Nan; Liu, Meichuan; Wang, Yanbin; Zhao, Guohua

2017-07-18

To improve selectivity of electrocatalytic degradation of toxic, odorous mercaptans, the fractal-structured dendritic Au/BDD (boron-doped diamond) anode with molecular recognition is fabricated through a facile replacement method. SEM and TEM characterizations show that the gold dendrites are single crystals and have high population of the Au (111) facet. The distinctive structure endows the electrode with advantages of low resistivity, high active surface area, and prominent electrocatalytic activity. To evaluate selectivity, the dendritic Au/BDD is applied in degrading two groups of synthetic wastewater containing thiophenol/2-mercaptobenzimidazole (targets) and phenol/2-hydroxybenzimidazole (interferences), respectively. Results show that targets removals reach 91%/94%, while interferences removals are only 58%/48% in a short time. The corresponding degradation kinetic constants of targets are 3.25 times and 4.1 times that of interferences in the same group, demonstrating modification of dendritic gold on BDD could effectively enhance electrocatalytic target-selectivity. XPS and EXAFS further reveal that the selective electrocatalytic degradation derives from preferential recognition and fast adsorption to thiophenol depending on strong Au-S bond. The efficient, selective degradation is attributed to the synergetic effects between accumulative behavior and outstanding electrochemical performances. This work provides a new strategy for selective electrochemical degradation of contaminants for actual wastewater treatment.

Facile electrocatalytic redox of hemoglobin by flower-like gold nanoparticles on boron-doped diamond surface.

PubMed

Li, Mingfang; Zhao, Guohua; Geng, Rong; Hu, Huikang

2008-11-01

The flower-like gold nanoparticles together with spherical and convex polyhedron gold nanoparticles were fabricated on boron-doped diamond (BDD) surface by one-step and simple electrochemical method through easily controlling the applied potential and the concentration of HAuCl(4). The recorded X-ray diffraction (XRD) patterns confirmed that these three shapes of gold nanoparticles were dominated by different crystal facets. The cyclic voltammetric results indicated that the morphology of gold nanoparticles plays big role in their electrochemical behaviors. The direct electrochemistry of hemoglobin (Hb) was realized on all the three different shapes of nanogold-attached BDD surface without the aid of any electron mediator. In pH 4.5 acetate buffer solutions (ABS), Hb showed a pair of well defined and quasi-reversible redox peaks. However, the results obtained demonstrated that the redox peak potential, the average surface concentration of electroactive heme, and the electron transfer rates of Hb are greatly dependent upon the surface morphology of gold nanoparticles. The electron transfer rate constant of hemoglobin over flower-like nanogold/BDD electrode was more than two times higher than that over spherical and convex polyhedron nanogold. The observed differences may be ascribed to the difference in gold particle characteristics including surface roughness, exposed surface area, and crystal structure.

Fluorination of Boron-Doped Diamond Film Electrodes for Minimization of Perchlorate Formation.

PubMed

Gayen, Pralay; Chaplin, Brian P

2017-08-23

This research investigated the effects of surface fluorination on both rates of organic compound oxidation (phenol and terephthalic acid (TA)) and ClO 4 - formation at boron-doped diamond (BDD) film anodes at 22 °C. Different fluorination methods (i.e., electrochemical oxidation with perfluorooctanoic acid (PFOA), radio frequency plasma, and silanization) were used to incorporate fluorinated moieties on the BDD surface, which was confirmed by X-ray photoelectron spectroscopy (XPS). The silanization method was found to be the most effective fluorination method using a 1H,1H,2H,2H-perfluorodecyltrichlorosilane precursor to form a self-assembled monolayer (SAM) on the oxygenated BDD surface. The ClO 4 - formation decreased from rates of 0.45 ± 0.03 mmol m -2 min -1 during 1 mM NaClO 3 oxidation and 0.28 ± 0.01 mmol m -2 min -1 during 10 mM NaCl oxidation on the BDD electrode to below detectable levels (<0.12 μmoles m -2 min -1 ) for the BDD electrode functionalized by a 1H,1H,2H,2H-perfluorodecyltrichlorosilane SAM. These decreases in rates corresponded to 99.94 and 99.85% decreases in selectivity for ClO 4 - formation during the electrolysis of 10 mM NaCl and 1 mM NaClO 3 electrolytes, respectively. By contrast, the oxidation rates of phenol were reduced by only 16.3% in the NaCl electrolyte and 61% in a nonreactive 0.1 M KH 2 PO 4 electrolyte. Cyclic voltammetry with Fe(CN) 6 3-/4- and Fe 3+/2+ redox couples indicated that the long fluorinated chains created a blocking layer on the BDD surface that inhibited charge transfer via steric hindrance and hydrophobic effects. The surface coverages and thicknesses of the fluorinated films controlled the charge transfer rates, which was confirmed by estimates of film thicknesses using XPS and density functional theory simulations. The aliphatic silanized electrode also showed very high stability during OH • production. Perchlorate formation rates were below the detection limit (<0.12 μmoles m -2 min -1 ) for up to 10 consecutive NaClO 3 oxidation experiments.

Electrochemical incineration of omeprazole in neutral aqueous medium using a platinum or boron-doped diamond anode: degradation kinetics and oxidation products.

PubMed

Cavalcanti, Eliane Bezerra; Garcia-Segura, Sergi; Centellas, Francesc; Brillas, Enric

2013-04-01

The electrochemical incineration of omeprazole, a widely prescribed gastrointestinal drug which is detected in natural waters, has been studied in a phosphate buffer of pH 7.0 by anodic oxidation with electrogenerated H(2)O(2) (AO-H(2)O(2)) operating at constant current density (j). The experiments were carried out in a cell equipped with either a Pt or a boron-doped diamond (BDD) anode and an air-diffusion cathode to continuously produce H(2)O(2). In these systems, organics are mainly oxidized by hydroxyl radicals formed at the Pt or BDD surface from water oxidation. A partial total organic carbon (TOC) abatement close to 78% for omeprazole was achieved by AO-H(2)O(2) with a BDD anode after consumption of 18 Ah L(-1) at 100 mA cm(-2), whereas the alternative use of Pt did not allow mineralizing the drug. However, the drug was totally removed using both anodes, although it decayed more rapidly using BDD. In this latter system, increasing j accelerated the degradation process, but lowering the mineralization current efficiency. Greater drug content also enhanced the degradation rate with higher mineralization degree and current efficiency. The kinetics for omeprazole decay always followed a pseudo-first-order reaction and its rate constant increased with increasing j and with decreasing its concentration. Seven heteroaromatic intermediates and four hydroxylated derivatives were detected by LC-MS, while nine short-linear carboxylic acids were identified and quantified by ion-exclusion HPLC. These acids were largely accumulated using Pt and rapidly removed using BDD, thus explaining the partial mineralization of omeprazole achieved by AO-H(2)O(2) with the latter anode. The release of inorganic ions such as NO(3)(-), NH(4)(+) and SO(4)(2-) was followed by ionic chromatography. A plausible reaction sequence for omeprazole mineralization involving all intermediates detected is proposed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Degradation of the endocrine disrupting chemicals (EDCs) carbamazepine, clofibric acid, and iopromide by corona discharge over water.

PubMed

Krause, Holger; Schweiger, Bianca; Schuhmacher, Jörg; Scholl, Saskia; Steinfeld, Ute

2009-04-01

Common wastewater treatment plants often do not eliminate endocrine disrupting chemicals (EDCs). Aqueous solutions of three EDCs were treated with an enhanced corona discharge technology. The three EDCs were clofibric acid, a blood lipid regulator, carbamazepine, an antiepileptic drug, and iopromide, a contrast media. To simulate real conditions, EDC solutions containing landfill leachate were also used. In our setup, two barrier electrodes provided an atmospheric pressure corona discharge over a thin water film, in which the counter-electrode was submerged. Clofibric acid, carbamazepine, and iopromide were effectively removed from a single solution. After a treatment of 15min, there were no traces of iopromide estrogen activity either as a single substance or as degradation products when using an E-Screen Assay. Continuous treatment was compared with pulsed treatment using carbamazepine solutions mixed with pretreated landfill leachate. Best degradation results were achieved with a 500 W continuous duty cycle treatment. Counter-electrodes from materials such as boron doped diamond (BDD), titanium iridium oxide, and iron were investigated for their influences on the process effectivity. Significant improvements were achieved by using an enclosed reactor, BDD electrodes, and circulating only a fresh air or argon/air mixture as cooling gas through the barrier electrodes.

Influence of the current density on the electrochemical treatment of concentrated 1-butyl-3-methylimidazolium chloride solutions on diamond electrodes.

PubMed

Marcionilio, Suzana M L de Oliveira; Alves, Gisele M; E Silva, Rachel B Góes; Marques, Pablo J Lima; Maia, Poliana D; Neto, Brenno A D; Linares, José J

2016-10-01

This paper focuses on the influence of the current density treatment of a concentrated 1-butyl-3-methylimidazolium chloride (BMImCl) solution on an electrochemical reactor with a boron-doped diamond (BDD) anode. The decrease in the total organic carbon (TOC) and the BMImCl concentration demonstrate the capability of BDD in oxidizing ionic liquids (ILs) and further mineralizing (to CO2 and NO3 (-)) more rapidly at higher current densities in spite of the reduced current efficiency of the process. Moreover, the presence of Cl(-) led to the formation of oxychlorinated anions (mostly ClO3 (-) and ClO4 (-)) and, in combination with the ammonia generated in the cathode from the nitrate reduction, chloramines, more intensely at higher current density. Finally, the analysis of the intermediates formed revealed no apparent influence of the current density on the BMImCl degradation mechanism. The current density presents therefore a complex influence on the IL treatment process that is discussed throughout this paper.

Chemometric study on the electrochemical incineration of diethylenetriaminepentaacetic acid using boron-doped diamond anode.

PubMed

Xian, Jiahui; Liu, Min; Chen, Wei; Zhang, Chunyong; Fu, Degang

2018-05-01

The electrochemical incineration of diethylenetriaminepentaacetic acid (DTPA) with boron-doped diamond (BDD) anode had been initially performed under galvanostatic conditions. The main and interaction effects of four operating parameters (flow rate, applied current density, sulfate concentration and initial DTPA concentration) on mineralization performance were investigated. Under similar experimental conditions, Doehlert matrix (DM) and central composite rotatable design (CCRD) were used as statistical multivariate methods in the optimization of the anodic oxidation processes. A comparison between DM model and CCRD model revealed that the former was more accurate, possibly due to its higher operating level numbers employed (7 levels for two variables). Despite this, these two models resulted in quite similar optimum operating conditions. The maximum TOC removal percentages at 180 min were 76.2% and 73.8% for case of DM and CCRD, respectively. In addition, with the aid of quantum chemistry calculation and LC/MS analysis, a plausible degradation sequence of DTPA on BDD anode was also proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Voltammetric determination of mixtures of caffeine and chlorogenic acid in beverage samples using a boron-doped diamond electrode.

PubMed

Yardım, Yavuz; Keskin, Ertugrul; Şentürk, Zühre

2013-11-15

Herein, a boron-doped diamond (BDD) electrode that is anodically pretreated was used for the simultaneous determination of caffeine (CAF) and chlorogenic acid (CGA) by cyclic and adsorptive stripping voltammetry. The dependence of peak current and potential on pH, scan rate, accumulation parameters and other experimental variables were studied. By using square-wave stripping mode after 60 s accumulation under open-circuit voltage, the BDD electrode was able to separate the oxidation peak potentials of CAF and CGA present in binary mixtures by about 0.4V in Britton-Robinson buffer at pH 1.0. The limits of detection were 0.107 µg mL(-1) (5.51×10(-7) M) for CAF, and 0.448 µg mL(-1) (1.26×10(-6) M) for CGA. The practical applicability of this methodology was tested in commercially available beverage samples. © 2013 Elsevier B.V. All rights reserved.

Veratric acid removal from water by electrochemical oxidation on BDD anode

NASA Astrophysics Data System (ADS)

Jum'h, Inshad; Abdelhay, Arwa; Telfah, Ahmad; Al-Akhras, M.-Ali; Al-Kazwini, Akeel; Rosiwal, Stefan

2018-02-01

The efficiency of boron doped diamond (BDD) in the electrochemical treatment of synthetically contaminated water with veratric acid (VA), one kind of polyphenolic type compounds, is investigated in this work. A BDD electrode was practically fabricated using hot filament chemical vapor deposition (HFCVD). Later on, the BDD electrode was implemented as an anode in a batch electrolytic reactor. The effect of operating factors such as the initial concentration of VA, NaCl addition, and supporting electrolyte type (H2SO4, H3PO4 and Na2SO4) was studied. The chemical oxygen demand (COD) measurements were conducted to study the VA electrolysis kinetics. The experimental data suggested that sodium sulfate was the best supporting electrolyte as the COD removal reached a percentage of 100% using 1 mmol/dm3 as VA concentration. The kinetics of the COD decay of the VA electrolysis were found to obey the pseudo-first order model. Remarkably, the electrolysis process is significantly speeded up once chloride is added to the reaction. The complete COD removal was achieved in 60 minutes of treatment.

Electrochemical Oxidation of Resorcinol in Aqueous Medium Using Boron-Doped Diamond Anode: Reaction Kinetics and Process Optimization with Response Surface Methodology

PubMed Central

Körbahti, Bahadır K.; Demirbüken, Pelin

2017-01-01

Electrochemical oxidation of resorcinol in aqueous medium using boron-doped diamond anode (BDD) was investigated in a batch electrochemical reactor in the presence of Na2SO4 supporting electrolyte. The effect of process parameters such as resorcinol concentration (100–500 g/L), current density (2–10 mA/cm2), Na2SO4 concentration (0–20 g/L), and reaction temperature (25–45°C) was analyzed on electrochemical oxidation using response surface methodology (RSM). The optimum operating conditions were determined as 300 mg/L resorcinol concentration, 8 mA/cm2 current density, 12 g/L Na2SO4 concentration, and 34°C reaction temperature. One hundred percent of resorcinol removal and 89% COD removal were obtained in 120 min reaction time at response surface optimized conditions. These results confirmed that the electrochemical mineralization of resorcinol was successfully accomplished using BDD anode depending on the process conditions, however the formation of intermediates and by-products were further oxidized at much lower rate. The reaction kinetics were evaluated at optimum conditions and the reaction order of electrochemical oxidation of resorcinol in aqueous medium using BDD anode was determined as 1 based on COD concentration with the activation energy of 5.32 kJ/mol that was supported a diffusion-controlled reaction. PMID:29082225

Electrochemically deposited Cu2O cubic particles on boron doped diamond substrate as efficient photocathode for solar hydrogen generation

NASA Astrophysics Data System (ADS)

Mavrokefalos, Christos K.; Hasan, Maksudul; Rohan, James F.; Compton, Richard G.; Foord, John S.

2017-06-01

Herein, we report a novel photocathode for the water splitting reaction. The electrochemical deposition of Cu2O particles on boron doped diamond (BDD) electrodes and the subsequent decoration with NiO nanoparticles by a dip coating method to act as co-catalyst for hydrogen evolution reaction is described. The morphology analysis by scanning electron microscope (SEM) revealed that Cu2O particles are cubic and decorated sporadically with NiO nanoparticles. X-ray photoelectron spectroscopy (XPS) confirmed the electronic interaction at the interface between Cu2O and NiO through a binding energy shift of the main Cu 2p peak. The photoelectrochemical (PEC) performance of NiO-Cu2O/BDD showed a much higher current density (-0.33 mA/cm2) and photoconversion efficiency (0.28%) compared to the unmodified Cu2O/BDD electrode, which are only -0.12 mA/cm2 and 0.06%, respectively. The enhancement in PEC performance is attributable to the synergy of NiO as an electron conduction mediator leading to the enhanced charge separation and transfer to the reaction interface for hydrogen evolution as evidenced by electrochemical impedance spectroscopy (EIS) and charge carrier density calculation. Stability tests showed that the NiO nanoparticles loading content on Cu2O surface is a crucial parameter in this regard.

Removal of organic contaminants from secondary effluent by anodic oxidation with a boron-doped diamond anode as tertiary treatment.

PubMed

Garcia-Segura, Sergi; Keller, Jürg; Brillas, Enric; Radjenovic, Jelena

2015-01-01

Electrochemical advanced oxidation processes (EAOPs) have been widely investigated as promising technologies to remove trace organic contaminants from water, but have rarely been used for the treatment of real waste streams. Anodic oxidation with a boron-doped diamond (BDD) anode was applied for the treatment of secondary effluent from a municipal sewage treatment plant containing 29 target pharmaceuticals and pesticides. The effectiveness of the treatment was assessed from the contaminants decay, dissolved organic carbon and chemical oxygen demand removal. The effect of applied current and pH was evaluated. Almost complete mineralization of effluent organic matter and trace contaminants can be obtained by this EAOP primarily due to the action of hydroxyl radicals formed at the BDD surface. The oxidation of Cl(-) ions present in the wastewater at the BDD anode gave rise to active chlorine species (Cl2/HClO/ClO(-)), which are competitive oxidizing agents yielding chloramines and organohalogen byproducts, quantified as adsorbable organic halogen. However, further anodic oxidation of HClO/ClO(-) species led to the production of ClO3(-) and ClO4(-) ions. The formation of these species hampers the application as a single-stage tertiary treatment, but posterior cathodic reduction of chlorate and perchlorate species may reduce the risks associated to their presence in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

Degradation of microcystin-RR using boron-doped diamond electrode.

PubMed

Zhang, Chunyong; Fu, Degang; Gu, Zhongze

2009-12-30

Microcystins (MCs), produced by blue-green algae, are one of the most common naturally occurring toxins found in natural environment. The presence of MCs in drinking water sources poses a great threat to people's health. In this study, the degradation behavior of microcystin-RR on boron-doped diamond (BDD) electrode was investigated under galvanostatic conditions. Such parameters as reaction time, supporting electrolyte and applied current density were varied in order to determine their effects on this oxidation process. The experimental results revealed the suitability of electrochemical processes employing BDD electrode for removing MC-RR from the solution. However, the efficient removal of MC-RR only occurred in the presence of sodium chloride that acted as redox mediators and the reaction was mainly affected by the chloride concentration (c(NaCl)) and applied current density (I(appl)). Full and quick removal of 0.50 microg/ml MC-RR in solution was achieved when the operating conditions of c(NaCl) and I(appl) were 20mM and 46.3 mA/cm(2), or 35 mM and 18.2 mA/cm(2) respectively. The kinetics for MC-RR degradation followed a pesudo-first order reaction in most cases, indicating the process was under mass transfer control. As a result of its excellent performance, the BDD technology could be considered as a promising alternative to promote the degradation of MC-RR than chlorination in drinking water supplies.

Body Dysmorphic Disorder: Gender differences and prevalence in a Pakistani medical student population

PubMed Central

Taqui, Ather M; Shaikh, Mehrine; Gowani, Saqib A; Shahid, Fatima; Khan, Asmatullah; Tayyeb, Syed M; Satti, Minahil; Vaqar, Talha; Shahid, Saman; Shamsi, Afreen; Ganatra, Hammad A; Naqvi, Haider A

2008-01-01

Background Body dysmorphic disorder (BDD) is a psychiatric disorder characterized by a preoccupation with an imagined or slight defect which causes significant distress or impairment in functioning. Few studies have assessed gender differences in BDD in a non clinical population. Also no study assessed BDD in medical students. This study was designed to determine the point prevalence of BDD in Pakistani medical students and the gender differences in prevalence of BDD, body foci of concern and symptoms of BDD. Methods The medical students enrolled in a medical university in Karachi, Pakistan filled out a self-report questionnaire which assessed clinical features of BDD. BDD was diagnosed according to the DSM-IV criteria. Results Out of the 156 students, 57.1% were female. A total of 78.8% of the students reported dissatisfaction with some aspect of their appearance and 5.8% met the DSM-IV criteria for BDD. The male to female ratio for BDD was 1.7. Regarding gender differences in body foci of concern, the top three reported foci of concern in male students were head hair (34.3%), being fat (32.8%), skin (14.9%) and nose(14.9%), whereas in females they were being fat (40.4%), skin (24.7%) and teeth (18%). Females were significantly more concerned about being fat (p = 0.005). Male students were significantly more concerned about being thin (p = 0.01) and about head hair (p = 0.012). Conclusion BDD is fairly common in our medical student population, with a higher prevalence in males. Important gender differences in BDD symptomatology and reported body foci of concern were identified which reflected the influence of media on body image perception. The impact of cultural factors on the prevalence as well as gender differences in BDD symptomatology was also established. PMID:18400091

Decolorization and degradation of reactive yellow HF aqueous solutions by electrochemical advanced oxidation processes.

PubMed

Bedolla-Guzman, A; Feria-Reyes, R; Gutierrez-Granados, S; Peralta-Hernández, Juan M

2017-05-01

Textile manufacturing is the one responsible for water bodies' contamination through the discharge of colored wastes. This work presents the study of reactive yellow HF (RYHF) dye degradation under two different electrochemical advanced oxidation processes (EAOP), namely anodic oxidation (AO) and electro-Fenton (EF)/boron-doped diamond (BDD) process. For the AO, 100 and 300 mg/L solutions using Pt and BDD as anodes in a 100 mL stirred tank cell were used, with a supporting electrolyte of 0.05 mol/L of Na 2 SO 4 at pH 3 under 30 and 50 mA/cm 2 current density. The EF/BDD process was carried out in a flow reactor at 4 and 7 L/min to degrade 100, 200, and 300 mg/L RYHF solutions under 50 and 80 mA/cm 2 . UV-Vis determinations were used for decolorization evaluation, while high-performance liquid chromatography (HPLC) method provided information on dye degradation rate.

Decolorization and mineralization of Allura Red AC aqueous solutions by electrochemical advanced oxidation processes.

PubMed

Thiam, Abdoulaye; Sirés, Ignasi; Garrido, José A; Rodríguez, Rosa M; Brillas, Enric

2015-06-15

The decolorization and mineralization of solutions containing 230 mg L(-1) of the food azo dye Allura Red AC at pH 3.0 have been studied upon treatment by electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with a stirred tank reactor containing a boron-doped diamond (BDD) or Pt anode and an air-diffusion cathode to generate H2O2. The main oxidants were hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between H2O2 and added Fe(2+). The oxidation ability increased in the sequence EO-H2O2 < EF < PEF and faster degradation was always obtained using BDD. PEF process with BDD yielded almost total mineralization following similar trends in SO4(2-), ClO4(-) and NO3(-) media, whereas in Cl(-) medium, mineralization was inhibited by the formation of recalcitrant chloroderivatives. GC-MS analysis confirmed the cleavage of the −N=N− bond with formation of two main aromatics in SO4(2-) medium and three chloroaromatics in Cl(-) solutions. The effective oxidation of final oxalic and oxamic acids by BDD along with the photolysis of Fe(III)-oxalate species by UVA light accounted for the superiority of PEF with BDD. NH4(+), NO3(-) and SO4(2-) ions were released during the mineralization. Copyright © 2015 Elsevier B.V. All rights reserved.

Degradation pathways of aniline in aqueous solutions during electro-oxidation with BDD electrodes and UV/H2O2 treatment.

PubMed

Benito, Aleix; Penadés, Aida; Lliberia, Josep Lluis; Gonzalez-Olmos, Rafael

2017-01-01

In this work, it has been studied the mineralization of aniline, a toxic substance of low biodegradability typically found in many industrial wastewaters, through electro-oxidation using boron doped diamond (BDD) electrodes and photo-oxidation (UV photolysis and UV/H 2 O 2 treatments). It was observed that in electro-oxidation and UV/H 2 O 2 , it was feasible to reach aniline mineralizations higher than 85%. Two different degradation routes have been observed during the aniline oxidation in these two treatments. The first route was the mineralization pathway, in which aniline was oxidized to CO 2 , water and nitrate. The second route was the polyaniline pathway in which polyanilines of high molecular weight are formed. The intermediate compounds involved in both degradation routes are different depending on the treatment used. In the electro-oxidation, denitrification processes were also observed. From an economical point of view, electro-oxidation of aniline using BDD electrodes is more interesting than UV/H 2 O 2 due it has an 87% lower operational cost. So, electro-oxidation using BDD electrodes seems to be a more suitable technique for the mineralization of wastewater containing aniline than UV or H 2 O 2 based technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Crystal-face-selective adsorption of Au nanoparticles onto polycrystalline diamond surfaces.

PubMed

Kondo, Takeshi; Aoshima, Shinsuke; Hirata, Kousuke; Honda, Kensuke; Einaga, Yasuaki; Fujishima, Akira; Kawai, Takeshi

2008-07-15

Crystal-face-selective adsorption of Au nanoparticles (AuNPs) was achieved on polycrystalline boron-doped diamond (BDD) surface via the self-assembly method combined with a UV/ozone treatment. To the best of our knowledge, this is the first report of crystal-face-selective adsorption on an inorganic solid surface. Hydrogen-plasma-treated BDD samples and those followed by UV/ozone treatment for 2 min or longer showed almost no adsorption of AuNP after immersion in the AuNP solution prepared by the citrate reduction method. However, the samples treated by UV/ozone for 10 s showed AuNP adsorption on their (111) facets selectively after the immersion. Moreover, the sample treated with UV/ozone for 40-60 s showed AuNP adsorption on the whole surface. These results indicate that the AuNP adsorption behavior can be controlled by UV/ozone treatment time. This phenomenon was highly reproducible and was applied to a two-step adsorption method, where AuNPs from different batches were adsorbed on the (111) and (100) surface in this order. Our findings may be of great value for the fabrication of advanced nanoparticle-based functional materials via bottom-up approaches with simple macroscale procedures.

Effect of nitro substituent on electrochemical oxidation of phenols at boron-doped diamond anodes.

PubMed

Jiang, Yi; Zhu, Xiuping; Li, Hongna; Ni, Jinren

2010-02-01

In order to investigate nitro-substitutent's effect on degradation of phenols at boron-doped diamond (BDD) anodes, cyclic voltammetries of three nitrophenol isomers: 2-nitrophenol (2NP), 3-nitrophenol (3NP) and 4-nitrophenol (4NP) were studied, and their bulk electrolysis results were compared with phenol's (Ph) under alkaline condition. The voltammetric study showed nitrophenols could be attacked by hydroxyl radicals and nitro-group was released from the aromatic ring. Results of bulk electrolysis showed degradation of all phenols were fit to a pseudo first-order equation and followed in this order: 2NP>4NP>3NP>Ph. Molecular structures, especially carbon atom charge, significantly influenced the electrochemical oxidation of these isomers. Intermediates were analyzed during the electrolysis process, and were mainly catechol, resorcinol, hydroquinone, and carboxylic acids, such as acetic acid and oxalic acid. A simple degradation pathway was proposed. Moreover, a linear increasing relationship between degradation rates and Hammett constants of the studied phenols was observed, which demonstrated that electrochemical oxidation of these phenols was mainly initiated by electrophilic attack of hydroxyl radicals at BDD anodes. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Diazo dye Congo Red degradation using a Boron-doped diamond anode: An experimental study on the effect of supporting electrolytes.

PubMed

Jalife-Jacobo, H; Feria-Reyes, R; Serrano-Torres, O; Gutiérrez-Granados, S; Peralta-Hernández, Juan M

2016-12-05

Diazo dye Congo Red (CR) solutions at 100mg/L, were degraded using different supporting electrolytes in an electrochemical advanced oxidation process (EAOPs), like the anodic oxidation (AOx/BDD). All experiments were carried out in a 3L flow reactor with a Boron-doped diamond (BDD) anode and stainless steel cathode (AISI 304), at 7.5, 15, 30 and 50mA/cm(2) current densities (j). Furthermore, each experiment was carried out under a flow rate of 7L/min. Additionally, HClO4, NaCl, Na2SO4, and H2SO4 were tested as supporting electrolytes at a 50mM concentration. The degradation process was at all times considerably faster in NaCl medium. Solutions containing SO4(2-) or ClO4(-) ions were less prompted to degradation due to the low oxidation power of these species into the bulk. Dissolved organic carbon (DOC) analysis, was carried out to evaluate the mineralization of CR. The degradation of CR, was evaluated with the HPLC analysis of the treated solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

Mechanical design of thin-film diamond crystal mounting apparatus with optimized thermal contact and crystal strain for coherence preservation x-ray optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shu, Deming; Shvydko, Yury; Stoupin, Stanislav

A method and mechanical design for a thin-film diamond crystal mounting apparatus for coherence preservation x-ray optics with optimized thermal contact and minimized crystal strain are provided. The novel thin-film diamond crystal mounting apparatus mounts a thin-film diamond crystal supported by a thick chemical vapor deposition (CVD) diamond film spacer with a thickness slightly thicker than the thin-film diamond crystal, and two groups of thin film thermal conductors, such as thin CVD diamond film thermal conductor groups separated by the thick CVD diamond spacer. The two groups of thin CVD film thermal conductors provide thermal conducting interface media with themore » thin-film diamond crystal. A piezoelectric actuator is integrated into a flexural clamping mechanism generating clamping force from zero to an optimal level.« less

Anodic stripping voltammetry of nickel ions and nickel hydroxide nanoparticles at boron-doped diamond electrodes

NASA Astrophysics Data System (ADS)

Musyarofah, N. R. R.; Gunlazuardi, J.; Einaga, Y.; Ivandini, T. A.

2017-04-01

Anodic stripping voltammetry (ASV) of nickel ions in phosphate buffer solution (PBS) have been investigated at boron-doped diamond (BDD) electrodes. The deposition potential at 0.1 V (vs. Ag/AgCl) for 300 s in 0.1 M PBS pH 3 was found as the optimum condition. The condition was applied for the determination of nickel contained in nickel hydroxide nanoparticles. A linear calibration curve can be achieved of Ni(OH)2-NPs in the concentration range of x to x mM with an estimated limit of detection (LOD) of 5.73 × 10-6 mol/L.

Relationship between anode material, supporting electrolyte and current density during electrochemical degradation of organic compounds in water.

PubMed

Guzmán-Duque, Fernando L; Palma-Goyes, Ricardo E; González, Ignacio; Peñuela, Gustavo; Torres-Palma, Ricardo A

2014-08-15

Taking crystal violet (CV) dye as pollutant model, the electrode, electrolyte and current density (i) relationship for electro-degrading organic molecules is discussed. Boron-doped diamond (BDD) or Iridium dioxide (IrO2) used as anode materials were tested with Na2SO4 or NaCl as electrolytes. CV degradation and generated oxidants showed that degradation pathways and efficiency are strongly linked to the current density-electrode-electrolyte interaction. With BDD, the degradation pathway depends on i: If ii(lim), generated oxidants play a major role in the CV elimination. When IrO2 was used, CV removal was not dependent on i, but on the electrolyte. Pollutant degradation in Na2SO4 on IrO2 seems to occur via IrO3; however, in the presence of NaCl, degradation was dependent on the chlorinated oxidative species generated. In terms of efficiency, the Na2SO4 electrolyte showed better results than NaCl when BDD anodes were employed. On the contrary, NaCl was superior when combined with IrO2. Thus, the IrO2/Cl(-) and BDD/SO4(2-) systems were better at removing the pollutant, being the former the most effective. On the other hand, pollutant degradation with the BDD/SO4(2-) and IrO2/Cl(-) systems is favored at low and high current densities, respectively. Copyright © 2014 Elsevier B.V. All rights reserved.

Controlled sp(2) Functionalization of Boron Doped Diamond as a Route for the Fabrication of Robust and Nernstian pH Electrodes.

PubMed

Ayres, Zoë J; Borrill, Alexandra J; Newland, Jonathan C; Newton, Mark E; Macpherson, Julie V

2016-01-05

The development of a voltammetric boron doped diamond (BDD) pH sensor is described. To obtain pH sensitivity, laser micromachining (ablation) is utilized to introduce controlled regions of sp(2) carbon into a high quality polycrystalline BDD electrode. The resulting sp(2) carbon is activated to produce electrochemically reducible quinone groups using a high temperature acid treatment, followed by anodic polarization. Once activated, no further treatment is required. The quinone groups show a linear (R(2) = 0.999) and Nernstian (59 mV/(pH unit)) pH-dependent reductive current-voltage response over a large analyzable pH range, from pH 2 to pH 12. Using the laser approach, it is possible to optimize sp(2) coverage on the BDD surface, such that a measurable pH response is recorded, while minimizing background currents arising from oxygen reduction reactions on sp(2) carbon in the potential region of interest. This enables the sensor to be used in aerated solutions, boding well for in situ analysis. The voltammetric response of the electrode is not compromised by the presence of excess metal ions such as Pb(2+), Cd(2+), Cu(2+), and Zn(2+). Furthermore, the pH sensor is stable over a 3 month period (the current time period of testing), can be stored in air between measurements, requires no reactivation of the surface between measurements, and can be reproducibly fabricated using the proposed approach. The efficacy of this pH sensor in a real-world sample is demonstrated with pH measurements in U.K. seawater.

Boron-doped diamond electrode: synthesis, characterization, functionalization and analytical applications.

PubMed

Luong, John H T; Male, Keith B; Glennon, Jeremy D

2009-10-01

In recent years, conductive diamond electrodes for electrochemical applications have been a major focus of research and development. The impetus behind such endeavors could be attributed to their wide potential window, low background current, chemical inertness, and mechanical durability. Several analytes can be oxidized by conducting diamond compared to other carbon-based materials before the breakdown of water in aqueous electrolytes. This is important for detecting and/or identifying species in solution since oxygen and hydrogen evolution do not interfere with the analysis. Thus, conductive diamond electrodes take electrochemical detection into new areas and extend their usefulness to analytes which are not feasible with conventional electrode materials. Different types of diamond electrodes, polycrystalline, microcrystalline, nanocrystalline and ultrananocrystalline, have been synthesized and characterized. Of particular interest is the synthesis of boron-doped diamond (BDD) films by chemical vapor deposition on various substrates. In the tetrahedral diamond lattice, each carbon atom is covalently bonded to its neighbors forming an extremely robust crystalline structure. Some carbon atoms in the lattice are substituted with boron to provide electrical conductivity. Modification strategies of doped diamond electrodes with metallic nanoparticles and/or electropolymerized films are of importance to impart novel characteristics or to improve the performance of diamond electrodes. Biofunctionalization of diamond films is also feasible to foster several useful bioanalytical applications. A plethora of opportunities for nanoscale analytical devices based on conducting diamond is anticipated in the very near future.

Highly Sensitive Detection of Urinary Cadmium to Assess Personal Exposure

PubMed Central

Argun, Avni A.; Banks, Ashley; Merlen, Gwendolynne; Tempelman, Linda A.; Becker, Michael F.; Schuelke, Thomas; Dweik, Badawi

2013-01-01

A series of Boron-Doped Diamond (BDD) ultramicroelectrode arrays were fabricated and investigated for their performance as electrochemical sensors to detect trace level metals such as cadmium. The steady-state diffusion behavior of these sensors was validated using cyclic voltammetry followed by electrochemical detection of cadmium in water and in human urine to demonstrate high sensitivity (>200 μA/ppb/cm2) and low background current (<4 nA). When an array of ultramicroelectrodes was positioned with optimal spacing, these BDD sensors showed a sigmoidal diffusion behavior. They also demonstrated high accuracy with linear dose dependence for quantification of cadmium in a certified reference river water sample from the National Institute of Standards and Technology (NIST) as well as in a human urine sample spiked with 0.25–1 ppb cadmium. PMID:23561905

An Experimental Approach to Controllably Vary Protein Oxidation While Minimizing Electrode Adsorption for Boron-Doped Diamond Electrochemical Surface Mapping Applications

PubMed Central

McClintock, Carlee S; Hettich, Robert L.

2012-01-01

Oxidative protein surface mapping has become a powerful approach for measuring the solvent accessibility of folded protein structures. A variety of techniques exist for generating the key reagent – hydroxyl radicals – for these measurements; however, these approaches range significantly in their complexity and expense of operation. This research expands upon earlier work to enhance the controllability of boron-doped diamond (BDD) electrochemistry as an easily accessible tool for producing hydroxyl radicals in order to oxidize a range of intact proteins. Efforts to modulate oxidation level while minimizing the adsorption of protein to the electrode involved the use of relatively high flow rates to reduce protein residence time inside the electrochemical flow chamber. Additionally, a different cell activation approach using variable voltage to supply a controlled current allowed us to precisely tune the extent of oxidation in a protein-dependent manner. In order to gain perspective on the level of protein adsorption onto the electrode surface, studies were conducted to monitor protein concentration during electrolysis and gauge changes in the electrode surface between cell activation events. This report demonstrates the successful use of BDD electrochemistry for greater precision in generating a target number of oxidation events upon intact proteins. PMID:23210708

A multidimensional high performance liquid chromatography method coupled with amperometric detection using a boron-doped diamond electrode for the simultaneous determination of sulfamethoxazole and trimethoprim in bovine milk.

PubMed

Andrade, Leonardo S; de Moraes, Marcela C; Rocha-Filho, Romeu C; Fatibello-Filho, Orlando; Cass, Quezia B

2009-11-10

The development and validation of a multidimensional HPLC method using an on-line clean-up column coupled with amperometric detection employing a boron-doped diamond (BDD) electrode for the simultaneous determination of sulfamethoxazole (SMX) and trimethoprim (TMP) in bovine milk are presented. Aliquots of pre-prepared skim-milk samples were directly injected into a RAM octyl-BSA column in order to remove proteins that otherwise would interfere with milk analysis. After exclusion of the milk proteins, SMX and TMP were transferred to the analytical column (an octyl column) and the separation of the compounds from one another and from other endogenous milk components was achieved. SMX and TMP were detected amperometrically at 1.25V vs. Ag/AgCl (3.0molL(-1) KCl). Results with good linearity in the concentration ranges 50-800 and 25-400microgL(-1) for SMX and TMP, respectively, were obtained and no fouling of the BDD electrode was observed within the experimental period of several hours. The intra- and inter-assay coefficients of variation were less than 10% for both drugs and the obtained LOD values for SMX and TMP were 25.0 and 15.0microgL(-1), respectively.

Advanced oxidation of real sulfamethoxazole + trimethoprim formulations using different anodes and electrolytes.

PubMed

Murillo-Sierra, Juan C; Sirés, Ignasi; Brillas, Enric; Ruiz-Ruiz, Edgar J; Hernández-Ramírez, Aracely

2018-02-01

A commercial sulfamethoxazole + trimethoprim formulation has been degraded in 0.050 M Na 2 SO 4 at pH 3.0 by electrochemical oxidation with electrogenerated H 2 O 2 (EO-H 2 O 2 ), electro-Fenton (EF), photoelectro-Fenton with a 6-W UVA lamp (PEF) and solar photoelectro-Fenton (SPEF). The tests were performed in an undivided cell with an IrO 2 -based, Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H 2 O 2 electrogeneration. The anode material had little effect on the accumulated H 2 O 2 concentration. Both drugs always obeyed a pseudo-first-order decay with low apparent rate constant in EO-H 2 O 2 . Much higher values were found in EF, PEF and SPEF, showing no difference because the main oxidant was always OH formed from Fenton's reaction between H 2 O 2 and added Fe 2+ . The solution mineralization increased in the sequence EO-H 2 O 2  < EF < PEF < SPEF regardless of the anode. The IrO 2 -based and Pt anodes behaved similarly but BDD was always more powerful. In SPEF, similar mineralization profiles were found for all anodes because of the rapid removal of photoactive intermediates by sunlight. About 87% mineralization was obtained as maximum for the powerful SPEF with BDD anode. Addition of Cl - enhanced the decay of both drugs due to their quicker reaction with generated active chlorine, but the formation of persistent chloroderivatives decelerated the mineralization process. Final carboxylic acids like oxalic and oxamic were detected, yielding Fe(III) complexes that remained stable in EF with BDD but were rapidly photolyzed in SPEF with BDD, explaining its superior mineralization ability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Occurrence and Removal of Organic Micropollutants in Landfill Leachates Treated by Electrochemical Advanced Oxidation Processes.

PubMed

Oturan, Nihal; van Hullebusch, Eric D; Zhang, Hui; Mazeas, Laurent; Budzinski, Hélène; Le Menach, Karyn; Oturan, Mehmet A

2015-10-20

In recent years, electrochemical advanced oxidation processes have been shown to be an effective alternative for the removal of refractory organic compounds from water. This study is focused on the effective removal of recalcitrant organic matter (micropollutants, humic substances, etc.) present in municipal solid waste landfill leachates. A mixture of eight landfill leachates has been studied by the electro-Fenton process using a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode or by the anodic oxidation process with a BDD anode. These processes exhibit great oxidation ability due to the in situ production of hydroxyl radicals ((•)OH), a highly powerful oxidizing species. Both electrochemical processes were shown to be efficient in the removal of dissolved total organic carbon (TOC) from landfill leachates. Regarding the electro-Fenton process, the replacement of the classical anode Pt by the anode BDD allows better performance in terms of dissolved TOC removal. The occurrence and removal yield of 19 polycyclic aromatic hydrocarbons, 15 volatile organic compounds, 7 alkylphenols, 7 polychlorobiphenyls, 5 organochlorine pesticides, and 2 polybrominated diphenyl ethers in landfill leachate were also investigated. Both electrochemical processes allow one to reach a quasicomplete removal (about 98%) of these organic micropollutants.

Gender similarities and differences in 200 individuals with body dysmorphic disorder⋆

PubMed Central

Phillips, Katharine A.; Menard, William; Fay, Christina

2006-01-01

Background Gender is a critically important moderator of psychopathology. However, gender similarities and differences in body dysmorphic disorder (BDD) have received scant investigation. In this study, we examined gender similarities and differences in the broadest sample in which this topic has been examined. Methods Two hundred subjects with BDD recruited from diverse sources were assessed with a variety of standard measures. Results There were more similarities than differences between men and women, but many gender differences were found. The men were significantly older and more likely to be single and living alone. Men were more likely to obsess about their genitals, body build, and thinning hair/balding; excessively lift weights; and have a substance use disorder. In contrast, women were more likely to obsess about their skin, stomach, weight, breasts/chest, buttocks, thighs, legs, hips, toes, and excessive body/facial hair, and they were excessively concerned with more body areas. Women also performed more repetitive and safety behaviors, and were more likely to camouflage and use certain camouflaging techniques, check mirrors, change their clothes, pick their skin, and have an eating disorder. Women also had earlier onset of subclinical BDD symptoms and more severe BDD as assessed by the Body Dysmorphic Disorder Examination. However, men had more severe BDD as assessed by the Psychiatric Status Rating Scale for Body Dysmorphic Disorder, and they had poorer Global Assessment of Functioning Scale scores, were less likely to be working because of psychopathology, and were more likely to be receiving disability, including disability for BDD. Conclusions The clinical features of BDD in men and women have many similarities but also some interesting and important differences. These findings have implications for the detection and treatment of BDD. PMID:16490564

Electrochemical wastewater treatment: influence of the type of carbon and of nitrogen on the organic load removal.

PubMed

Fernandes, Annabel; Coelho, João; Ciríaco, Lurdes; Pacheco, Maria José; Lopes, Ana

2016-12-01

Boron-doped diamond (BDD) and Ti/Pt/PbO 2 anodes were utilized to perform the electrodegradation of synthetic samples containing humic acid in the presence of different organic and inorganic carbon-containing and nitrogen-containing compounds. The influence of the chloride ion in the degradation process of the different synthetic samples was also assessed. The results showed that the anodic oxidation process can efficiently degrade recalcitrant compounds such as humic acid. The presence of carbonate in solution enhances the nitrogen removal, whereas it hinders the oxidation of the organic compounds. When organic nitrogen is present, it is converted to NH 4 + , which in turn is oxidized to nitrate and to volatile nitrogen compounds. Hydroxyl radicals are more prone to oxidize the organic nitrogen than the ammonium nitrogen. The presence of chloride enhances the organic matter and nitrogen removal rates, BDD being the anode material that yields the highest removals.

Improving the catalytic effect of peroxodisulfate and peroxodiphosphate electrochemically generated at diamond electrode by activation with light irradiation.

PubMed

de Araújo, Danyelle Medeiros; Sáez, Cristina; Cañizares, Pablo; Rodrigo, Manuel Andrés; Martínez-Huitle, Carlos A

2018-05-21

Boron doped diamond (BDD) anode has been used to oxidatively remove Rhodamine B (RhB), as persistent organic pollutant, from synthetic wastewater by electrolysis, photoelectrolysis and chemical oxidation containing sulfate and phosphate as supporting electrolytes. RhB is effectively oxidized by electrolysis and by chemical oxidation with the oxidants separately produced by electrolyzing sulfate or phosphate solutions (peroxodisulfate and peroxodiphosphate, respectively). The results showed that light irradiation improved the electrolysis of RhB due to the activation of oxidants under irradiation at high current densities. Meanwhile, the efficiency of the chemical oxidation approach by ex situ electrochemical production of oxidants was not efficient to degrade RhB. Copyright © 2018 Elsevier Ltd. All rights reserved.

Simultaneous square-wave voltammetric determination of aspartame and cyclamate using a boron-doped diamond electrode.

PubMed

Medeiros, Roberta Antigo; de Carvalho, Adriana Evaristo; Rocha-Filho, Romeu C; Fatibello-Filho, Orlando

2008-07-30

A simple and highly selective electrochemical method was developed for the simultaneous determination of aspartame and cyclamate in dietary products at a boron-doped diamond (BDD) electrode. In square-wave voltammetric (SWV) measurements, the BDD electrode was able to separate the oxidation peak potentials of aspartame and cyclamate present in binary mixtures by about 400 mV. The detection limit for aspartame in the presence of 3.0x10(-4) mol L(-1) cyclamate was 4.7x10(-7) mol L(-1), and the detection limit for cyclamate in the presence of 1.0x10(-4) mol L(-1) aspartame was 4.2x10(-6) mol L(-1). When simultaneously changing the concentration of both aspartame and cyclamate in a 0.5 mol L(-1) sulfuric acid solution, the corresponding detection limits were 3.5x10(-7) and 4.5x10(-6) mol L(-1), respectively. The relative standard deviation (R.S.D.) obtained was 1.3% for the 1.0x10(-4) mol L(-1) aspartame solution (n=5) and 1.1% for the 3.0x10(-3) mol L(-1) cyclamate solution. The proposed method was successfully applied in the determination of aspartame in several dietary products with results similar to those obtained using an HPLC method at 95% confidence level.

Electrochemical mineralization and detoxification of naphthenic acids on boron-doped diamond anodes.

PubMed

Diban, Nazely; Urtiaga, Ane

2018-01-05

Electrochemical oxidation (ELOX) with boron-doped diamond (BDD) anodes was successfully applied to degrade a model aqueous solution of a mixture of commercial naphthenic acids (NAs). The model mixture was prepared resembling the NA and salt composition of oil sands process-affected water (OSPW) as described in the literature. The initial concentration of NAs between 70 and 120 mg/L did not influence the electrooxidation kinetics. However, increasing the applied current density from 20 to 100 A/m 2 and the initial chloride concentration from 15 to 70 and 150 mg/L accelerated the rate of NA degradation. At higher chloride concentration, the formation of indirect oxidative species could contribute to the faster oxidation of NAs. Complete chemical oxygen demand removal at an initial NA concentration of 120 mg/L, 70 mg/L of chloride and applied 50 A/m 2 of current density was achieved, and 85% mineralization, defined as the decrease of the total organic carbon (TOC) content, was attained. Moreover, after 6 h of treatment and independently on the experimental conditions, the formation of more toxic species, i.e. perchlorate and organochlorinated compounds, was not detected. Finally, the use of ELOX with BDD anodes produced a 7 to 11-fold reduction of toxicity (IC 50 towards Vibrio fischeri) after 2 h of treatment.

Study of degradation intermediates formed during electrochemical oxidation of pesticide residue 2,6-dichlorobenzamide (BAM) in chloride medium at boron doped diamond (BDD) and platinum anodes.

PubMed

Madsen, Henrik Tækker; Søgaard, Erik Gydesen; Muff, Jens

2015-02-01

For electrochemical oxidation to become applicable in water treatment outside of laboratories, a number of challenges must be elucidated. One is the formation and fate of degradation intermediates of targeted organics. In this study the degradation of the pesticide residue 2,6-dichlorobenzamide, an important groundwater pollutant, was investigated in a chloride rich solution with the purpose of studying the effect of active chlorine on the degradation pathway. To study the relative importance of the anodic oxidation and active chlorine oxidation in the bulk solution, a non-active BDD and an active Pt anode were compared. Also, the effect of the active chlorine oxidation on the total amount of degradation intermediates was investigated. We found that for 2,6-dichlorobenzamide, active chlorine oxidation was determining for the initial step of the degradation, and therefore yielded a completely different set of degradation intermediates compared to an inert electrolyte. For the Pt anode, the further degradation of the intermediates was also largely dependent on active chlorine oxidation, while for the BDD anode anodic oxidation was most important. It was also found that the presence of active chlorine led to fewer degradation intermediates compared to treatment in an inert electrolyte. Copyright © 2014 Elsevier Ltd. All rights reserved.

Performance of (in)active anodic materials for the electrooxidation of phenolic wastewaters from cashew-nut processing industry.

PubMed

Oliveira, Edna M S; Silva, Francisco R; Morais, Crislânia C O; Oliveira, Thiago Mielle B F; Martínez-Huitle, Carlos A; Motheo, Artur J; Albuquerque, Cynthia C; Castro, Suely S L

2018-06-01

This study investigated the anodic oxidation of phenolic wastewater generated by cashew-nut processing industry (CNPI) using active (Ti/RuO 2 -TiO 2 ) and inactive (boron doped diamond, BDD) anodes. During electrochemical treatment, various operating parameters were investigated, such as current density, chemical oxygen demand (COD), total phenols, O 2 production, temperature, pH, as well as current efficiency and energy consumption. After electrolysis under optimized working conditions, samples were evaluated by chromatography and toxicological tests against L. sativa. When both electrode materials were compared under the same operating conditions, higher COD removal efficiency was achieved for BDD anode; achieving lower energy requirements when compared with the values estimated for Ti/RuO 2 -TiO 2 . The presence of Cl - in the wastewater promoted the electrogeneration of strong oxidant species as chlorine, hypochlorite and mainly hypochlorous acid, increasing the efficiency of degradation process. Regarding the temperature effect, BDD showed slower performances than those achieved for Ti/RuO 2 -TiO 2 . Chromatographic and phytotoxicity studies indicated formation of some by-products after electrolytic process, regardless of the anode evaluated, and phytotoxic action of the effluent. Results encourage the applicability of the electrochemical method as wastewater treatment process for the CNPI, reducing depuration time. Copyright © 2018. Published by Elsevier Ltd.

Electro-Fenton for control and removal of micropollutants - process optimization and energy efficiency.

PubMed

Mousset, E; Wang, Z; Lefebvre, O

2016-11-01

The removal of micropollutants is an important environmental and health issue. Electro-Fenton offers an electrochemical advanced treatment that is particularly effective for the breakdown of aromatic contaminants. Due to the wide variety of chemicals, it is preferable to analyze model contaminants, such as phenol, when optimizing and assessing the efficacy of a novel treatment process. In this study, we therefore made use of innovative types of electrode material and optimized operating parameters (current density and aeration rate) for the removal of phenol by electro-Fenton, with a view to maximize the energy efficiency of the process. By determining the best current density (1.25 mA cm -2 ), frequency of aeration (continuous) and by using a boron-doped diamond (BDD) anode, it was possible to achieve over 98.5% phenol (1 mM) removal within 1.5 h. BDD further outcompeted platinum as anode material in terms of mineralization rate and yield, and displayed low energy consumption of 0.08 kWh (g-TOC) -1 , about one order of magnitude lower than other advanced oxidation processes, such as UV/TiO 2 and UV/O 3 . Furthermore, a carbon cloth anode proved even more cost-effective than BDD if the end goal is the removal of phenol by electro-Fenton instead of complete mineralization.

SEMICONDUCTOR TECHNOLOGY A new cleaning process for the metallic contaminants on a post-CMP wafer's surface

NASA Astrophysics Data System (ADS)

Baohong, Gao; Yuling, Liu; Chenwei, Wang; Yadong, Zhu; Shengli, Wang; Qiang, Zhou; Baimei, Tan

2010-10-01

This paper presents a new cleaning process using boron-doped diamond (BDD) film anode electrochemical oxidation for metallic contaminants on polished silicon wafer surfaces. The BDD film anode electrochemical oxidation can efficiently prepare pyrophosphate peroxide, pyrophosphate peroxide can oxidize organic contaminants, and pyrophosphate peroxide is deoxidized into pyrophosphate. Pyrophosphate, a good complexing agent, can form a metal complex, which is a structure consisting of a copper ion, bonded to a surrounding array of two pyrophosphate anions. Three polished wafers were immersed in the 0.01 mol/L CuSO4 solution for 2 h in order to make comparative experiments. The first one was cleaned by pyrophosphate peroxide, the second by RCA (Radio Corporation of America) cleaning, and the third by deionized (DI) water. The XPS measurement result shows that the metallic contaminants on wafers cleaned by the RCA method and by pyrophosphate peroxide is less than the XPS detection limits of 1 ppm. And the wafer's surface cleaned by pyrophosphate peroxide is more efficient in removing organic carbon residues than RCA cleaning. Therefore, BDD film anode electrochemical oxidation can be used for microelectronics cleaning, and it can effectively remove organic contaminants and metallic contaminants in one step. It also achieves energy saving and environmental protection.

In vivo pH monitoring using boron doped diamond microelectrode and silver needles: Application to stomach disorder diagnosis

NASA Astrophysics Data System (ADS)

Fierro, Stéphane; Seishima, Ryo; Nagano, Osamu; Saya, Hideyuki; Einaga, Yasuaki

2013-11-01

This study presents the in vivo electrochemical monitoring of pH using boron doped diamond (BDD) microelectrode and silver needles for potential application in medical diagnosis. Accurate calibration curve for pH determination were obtained through in vitro electrochemical measurements. The increase induced in stomach pH by treatment with pantoprazole was used to demonstrate that it is possible to monitor the pH in vivo using the simple and noninvasive system proposed herein. Using the results of the in vivo and in vitro experiments, a quantitative analysis of the increase in stomach pH is also presented. It is proposed that the catheter-free pH monitoring system presented in this study could be potentially employed in any biological environment.

In vivo pH monitoring using boron doped diamond microelectrode and silver needles: application to stomach disorder diagnosis.

PubMed

Fierro, Stéphane; Seishima, Ryo; Nagano, Osamu; Saya, Hideyuki; Einaga, Yasuaki

2013-11-19

This study presents the in vivo electrochemical monitoring of pH using boron doped diamond (BDD) microelectrode and silver needles for potential application in medical diagnosis. Accurate calibration curve for pH determination were obtained through in vitro electrochemical measurements. The increase induced in stomach pH by treatment with pantoprazole was used to demonstrate that it is possible to monitor the pH in vivo using the simple and noninvasive system proposed herein. Using the results of the in vivo and in vitro experiments, a quantitative analysis of the increase in stomach pH is also presented. It is proposed that the catheter-free pH monitoring system presented in this study could be potentially employed in any biological environment.

Method of improving field emission characteristics of diamond thin films

DOEpatents

Krauss, A.R.; Gruen, D.M.

1999-05-11

A method of preparing diamond thin films with improved field emission properties is disclosed. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display. 3 figs.

Method of improving field emission characteristics of diamond thin films

DOEpatents

Krauss, Alan R.; Gruen, Dieter M.

1999-01-01

A method of preparing diamond thin films with improved field emission properties. The method includes preparing a diamond thin film on a substrate, such as Mo, W, Si and Ni. An atmosphere of hydrogen (molecular or atomic) can be provided above the already deposited film to form absorbed hydrogen to reduce the work function and enhance field emission properties of the diamond film. In addition, hydrogen can be absorbed on intergranular surfaces to enhance electrical conductivity of the diamond film. The treated diamond film can be part of a microtip array in a flat panel display.

Synthesis, characterization, and electrochemical behavior of Au@Pd core shell nanoparticles

NASA Astrophysics Data System (ADS)

Wicaksono, W. P.; Ivandini, T. A.

2017-04-01

Au@Pd core shell nanoparticles (Au@Pd CSNPs) were successfully synthesized using a seed-mediated growth method. Firstly, a pale pink gold seed solution was used to produce a pale purple gold nanoparticles (AuNPs) core solution. Then, three series of Pd shell thickness using 20μ, 100 μL, and 500 μL of PdCl2 produced purple, brown, and deep brown of Au@Pd CSNPs respectively. A strong absorbance UV-Visible spectrum with peaks at 285 nm and 535 nm was identified for AuNPs formation. The disappearance of the peak at 535 nm was indicated the Au@Pd CSNPs formation. The electrochemical properties were examined in phosphate buffer pH 7 using cyclic voltammetry technique with boron-doped diamond (BDD) as working electrode showed a couple oxidation and reduction peak of gold at 0.67 V and at 0.33 V, respectively. The Au@Pd CNPs will be used for modification of BDD electrodes.

Maximization of current efficiency for organic pollutants oxidation at BDD, Ti/SnO2-Sb/PbO2, and Ti/SnO2-Sb anodes.

PubMed

Xing, Xuan; Ni, Jinren; Zhu, Xiuping; Jiang, Yi; Xia, Jianxin

2018-08-01

Whereas electrochemical oxidation is noted for its ability to degrade bio-refractory organics, it has also been incorrectly criticized for excessive energy consumption. The present paper rectifies this misunderstanding by demonstrating that the energy actually consumed in the degradation process is much less than that wasted in the side reaction of oxygen evolution. To minimize the side reaction, the possible highest instantaneous current efficiency (PHICE) for electrochemical oxidation of phenol at Boron-doped Diamond (BDD), Ti/SnO 2 -Sb/PbO 2 (PbO 2 ), and Ti/SnO 2 -Sb (SnO 2 ) anodes has been investigated systematically, and found to reach almost 100% at the BDD anode compared with 23% at the PbO 2 anode and 9% at the SnO 2 anode. The significant discrepancy between PHICE values at the various anodes is interpreted in terms of different existing forms of hydroxyl radicals. For each anode system, the PHICEs are maintained experimentally using a computer-controlled exponential decay current mode throughout the electrolysis process. For applications, the minimized energy consumption is predicted by response surface methodology, and demonstrated for the BDD anode system. Consequently, almost 100% current efficiency is achieved (for a relatively meagre energy consumption of 17.2 kWh kgCOD -1 ) along with excellent COD degradation efficiency by optimizing the initial current density, flow rate, electrolysis time, and exponential decay constant. Compared with galvanostatic conditions, over 70% of the energy is saved in the present study, thus demonstrating the great potential of electrochemical oxidation for practical applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

A novel paper-based device coupled with a silver nanoparticle-modified boron-doped diamond electrode for cholesterol detection.

PubMed

Nantaphol, Siriwan; Chailapakul, Orawon; Siangproh, Weena

2015-09-03

A novel paper-based analytical device (PAD) coupled with a silver nanoparticle-modified boron-doped diamond (AgNP/BDD) electrode was first developed as a cholesterol sensor. The AgNP/BDD electrode was used as working electrode after modification by AgNPs using an electrodeposition method. Wax printing was used to define the hydrophilic and hydrophobic areas on filter paper, and then counter and reference electrodes were fabricated on the hydrophilic area by screen-printing in house. For the amperometric detection, cholesterol and cholesterol oxidase (ChOx) were directly drop-cast onto the hydrophilic area, and H2O2 produced from the enzymatic reaction was monitored. The fabricated device demonstrated a good linearity (0.39 mg dL(-1) to 270.69 mg dL(-1)), low detection limit (0.25 mg dL(-1)), and high sensitivity (49.61 μA mM(-1) cm(-2)). The precision value for ten replicates was 3.76% RSD for 1 mM H2O2. In addition, this biosensor exhibited very high selectivity for cholesterol detection and excellent recoveries for bovine serum analysis (in the range of 99.6-100.8%). The results showed that this new sensing platform will be an alternative tool for cholesterol detection in routine diagnosis and offers the advantages of low sample/reagent consumption, low cost, portability, and short analysis time. Copyright © 2015 Elsevier B.V. All rights reserved.

Electrochemical oxidation and electroanalytical determination of xylitol at a boron-doped diamond electrode.

PubMed

Lourenço, Anabel S; Sanches, Fátima A C; Magalhães, Renata R; Costa, Daniel J E; Ribeiro, Williame F; Bichinho, Kátia M; Salazar-Banda, Giancarlo R; Araújo, Mário C U

2014-02-01

Xylitol is a reduced sugar with anticariogenic properties used by insulin-dependent diabetics, and which has attracted great attention of the pharmaceutical, cosmetics, food and dental industries. The detection of xylitol in different matrices is generally based on separation techniques. Alternatively, in this paper, the application of a boron-doped diamond (BDD) electrode allied to differing voltammetric techniques is presented to study the electrochemical behavior of xylitol, and to develop an analytical methodology for its determination in mouthwash. Xylitol undergoes two oxidation steps in an irreversible diffusion-controlled process (D=5.05 × 10(-5)cm(2)s(-1)). Differential pulse voltammetry studies revealed that the oxidation mechanism for peaks P1 (3.4 ≤ pH ≤ 8.0), and P2 (6.0 ≤ pH ≤ 9.0) involves transfer of 1H(+)/1e(-), and 1e(-) alone, respectively. The oxidation process P1 is mediated by the (•)OH generated at the BDD hydrogen-terminated surface. The maximum peak current was obtained at a pH of 7.0, and the electroanalytical method developed, (employing square wave voltammetry) yielded low detection (1.3 × 10(-6) mol L(-1)), and quantification (4.5 × 10(-6) mol L(-1)) limits, associated with good levels of repeatability (4.7%), and reproducibility (5.3%); thus demonstrating the viability of the methodology for detection of xylitol in biological samples containing low concentrations. © 2013 Elsevier B.V. All rights reserved.

Electrochemical treatment of anti-cancer drug carboplatin on mixed-metal oxides and boron doped diamond electrodes: Density functional theory modelling and toxicity evaluation.

PubMed

Barışçı, Sibel; Turkay, Ozge; Ulusoy, Ebru; Soydemir, Gülfem; Seker, Mine Gul; Dimoglo, Anatoli

2018-02-15

This study represents the electrooxidation of anti-cancer drug carboplatin (CrbPt) with different mixed metal oxide (MMO) and boron doped diamond (BDD) electrodes. The most effective anode was found as Ti/RuO 2 with the complete degradation of CrbPt in just 5min. The effect of applied current density, pH and electrolyte concentration on CrbPt degradation has been studied. The degradation of CrbPt significantly increased at the initial stages of the process with increasing current density. However, further increase in current density did not affect the degradation rate. While complete degradation of CrbPt was provided at pH 7, the degradation rates were 49% and 75% at pH 9 and 4, respectively. Besides, increasing supporting electrolyte (Na 2 SO 4 ) concentration provided higher degradation rate but further increase in Na 2 SO 4 concentration did not provide higher degradation rate due to excess amount of SO 4 -2 . According to the DFT calculations, the formation of [Pt(NH 3 ) 2 (H 2 O) 2 ] 2+ and [Pt(NH 3 ) 2 (OH) 2 ] takes place with molecular weights of 265 and 263gmol -1 , respectively. Toxicity of treated samples at BDD and Ti/RuO 2 electrodes has been also evaluated in this study. The results showed that Ti/RuO 2 anode provided zero toxicity at the end of the process. Copyright © 2017 Elsevier B.V. All rights reserved.

Electrochemical mineralization of cephalexin using a conductive diamond anode: A mechanistic and toxicity investigation.

PubMed

Coledam, Douglas A C; Pupo, Marília M S; Silva, Bianca F; Silva, Adilson J; Eguiluz, Katlin I B; Salazar-Banda, Giancarlo R; Aquino, José M

2017-02-01

The contamination of surface and ground water by antibiotics is of significant importance due to their potential chronic toxic effects to the aquatic and human lives. Thus, in this work, the electrochemical oxidation of cephalexin (CEX) was carried out in a one compartment filter-press flow cell using a boron-doped diamond (BDD) electrode as anode. During the electrolysis, the investigated variables were: supporting electrolyte (Na 2 SO 4 , NaCl, NaNO 3 , and Na 2 CO 3 ) at constant ionic strength (0.1 M), pH (3, 7, 10, and without control), and current density (5, 10 and 20 mA cm -2 ). The oxidation and mineralization of CEX were assessed by high performance liquid chromatography, coupled to mass spectrometry and total organic carbon. The oxidation process of CEX was dependent on the type of electrolyte and on pH of the solution due to the distinct oxidant species electrogenerated; however, the conversion of CEX and its hydroxylated intermediates to CO 2 depends only on their diffusion to the surface of the BDD. In the final stages of electrolysis, an accumulation of recalcitrant oxamic and oxalic carboxylic acids, was detected. Finally, the growth inhibition assay with Escherichia coli cells showed that the toxicity of CEX solution decreased along the electrochemical treatment due to the rupture of the β-lactam ring of the antibiotic. Copyright © 2016 Elsevier Ltd. All rights reserved.

Degradation of the insecticide propoxur by electrochemical advanced oxidation processes using a boron-doped diamond/air-diffusion cell.

PubMed

Guelfi, Diego Roberto Vieira; Gozzi, Fábio; Sirés, Ignasi; Brillas, Enric; Machulek, Amílcar; de Oliveira, Silvio César

2017-03-01

A solution with 0.38 mM of the pesticide propoxur (PX) at pH 3.0 has been comparatively treated by electrochemical oxidation with electrogenerated H 2 O 2 (EO-H 2 O 2 ), electro-Fenton (EF), and photoelectro-Fenton (PEF). The trials were carried out with a 100-mL boron-doped diamond (BDD)/air-diffusion cell. The EO-H 2 O 2 process had the lowest oxidation ability due to the slow reaction of intermediates with • OH produced from water discharge at the BDD anode. The EF treatment yielded quicker mineralization due to the additional • OH formed between added Fe 2+ and electrogenerated H 2 O 2 . The PEF process was the most powerful since it led to total mineralization by the combined oxidative action of hydroxyl radicals and UVA irradiation. The PX decay agreed with a pseudo-first-order kinetics in EO-H 2 O 2 , whereas in EF and PEF, it obeyed a much faster pseudo-first-order kinetics followed by a much slower one, which are related to the oxidation of its Fe(II) and Fe(III) complexes, respectively. EO-H 2 O 2 showed similar oxidation ability within the pH range 3.0-9.0. The effect of current density and Fe 2+ and substrate contents on the performance of the EF process was examined. Two primary aromatic products were identified by LC-MS during PX degradation.

Degradation of anti-inflammatory drug ketoprofen by electro-oxidation: comparison of electro-Fenton and anodic oxidation processes.

PubMed

Feng, Ling; Oturan, Nihal; van Hullebusch, Eric D; Esposito, Giovanni; Oturan, Mehmet A

2014-01-01

The electrochemical degradation of the nonsteroidal anti-inflammatory drug ketoprofen in tap water has been studied using electro-Fenton (EF) and anodic oxidation (AO) processes with platinium (Pt) and boron-doped diamond (BDD) anodes and carbon felt cathode. Fast degradation of the parent drug molecule and its degradation intermediates leading to complete mineralization was achieved by BDD/carbon felt, Pt/carbon felt, and AO with BDD anode. The obtained results showed that oxidative degradation rate of ketoprofen and mineralization of its aqueous solution increased by increasing applied current. Degradation kinetics fitted well to a pseudo-first-order reaction. Absolute rate constant of the oxidation of ketoprofen by electrochemically generated hydroxyl radicals was determined to be (2.8 ± 0.1) × 10(9) M(-1) s(-1) by using competition kinetic method. Several reaction intermediates such as 3-hydroxybenzoic acid, pyrogallol, catechol, benzophenone, benzoic acid, and hydroquinone were identified by high-performance liquid chromatography (HPLC) analyses. The formation, identification, and evolution of short-chain aliphatic carboxylic acids like formic, acetic, oxalic, glycolic, and glyoxylic acids were monitored with ion exclusion chromatography. Based on the identified aromatic/cyclic intermediates and carboxylic acids as end products before mineralization, a plausible mineralization pathway was proposed. The evolution of the toxicity during treatments was also monitored using Microtox method, showing a faster detoxification with higher applied current values.

Simultaneous detection of pH changes and histamine release from oxyntic glands in isolated stomach.

PubMed

Bitziou, Eleni; O'Hare, Danny; Patel, Bhavik Anil

2008-11-15

Real-time simultaneous detection of changes in pH and levels of histamine over the oxyntic glands of guinea pig stomach have been investigated. An iridium oxide pH microelectrode was used in a potentiometric mode to record the pH decrease associated with acid secretion when the sensor approached the isolated tissue. A boron-doped diamond (BDD) microelectrode was used in an amperometric mode to detect histamine when the electrode was placed over the tissue. Both sensors provided stable and reproducible responses that were qualitatively consistent with the signaling mechanism for acid secretion at the stomach. Simultaneous measurements in the presence of pharmacological treatments produced significant variations in the signals obtained by both sensors. As the H2 receptor antagonist cimetidine was perfused to the tissue, histamine levels increased that produced an increase in the signal of the BDD electrode whereas the pH sensor recorded a decrease in acid secretion as expected. Addition of acetylcholine (ACh) stimulated additional acid secretion detected with the pH microelectrode whereas the BDD sensor recorded the histamine levels decreasing significantly. This result shows that the primary influence of ACh is directly on the parietal cell receptors rather then the ECL cell receptors of the oxyntic glands. These results highlight the power of this simultaneous detection technique in the monitoring and diagnosis of physiological significant signaling mechanisms and pathways.

Construction and evaluation of high-quality n-ZnO nanorod/p-diamond heterojunctions.

PubMed

Wang, C D; Jha, S K; Chen, Z H; Ng, T W; Liu, Y K; Yuen, M F; Lu, Z Z; Kwok, S Y; Zapien, J A; Bello, I; Lee, C S; Zhang, W J

2012-06-01

Vertically-aligned ZnO nanorods (NRs) arrays were synthesized by a low-temperature solution method on boron-doped diamond (BDD) films. The morphology, growth direction, and crystallinity of the ZnO NRs were studied by scanning electron microscopy, X-ray diffraction and cathodoluminescence. Electrical characterization of the ZnO NR/BBD heterostructures revealed characteristic p-n junction properties with an on/off ratio of about 50 at +/- 4 V and a small reverse leakage current approximately 1 microA. Moreover, the junctions showed an ideality factor around 1.0 at a low forward voltage from 0 to 0.3 V and about 2.1 for an increased voltage ranging from 1.2 to 3.0 V, being consistent with that of an ideal diode according to the Sah-Noyce-Shockley theory.

SERS activity of Ag decorated nanodiamond and nano-β-SiC, diamond-like-carbon and thermally annealed diamond thin film surfaces.

PubMed

Kuntumalla, Mohan Kumar; Srikanth, Vadali Venkata Satya Siva; Ravulapalli, Satyavathi; Gangadharini, Upender; Ojha, Harish; Desai, Narayana Rao; Bansal, Chandrahas

2015-09-07

In the recent past surface enhanced Raman scattering (SERS) based bio-sensing has gained prominence owing to the simplicity and efficiency of the SERS technique. Dedicated and continuous research efforts have been made to develop SERS substrates that are not only stable, durable and reproducible but also facilitate real-time bio-sensing. In this context diamond, β-SiC and diamond-like-carbon (DLC) and other related thin films have been promoted as excellent candidates for bio-technological applications including real time bio-sensing. In this work, SERS activities of nanodiamond, nano-β-SiC, DLC, thermally annealed diamond thin film surfaces were examined. DLC and thermally annealed diamond thin films were found to show SERS activity without any metal nanostructures on their surfaces. The observed SERS activities of the considered surfaces are explained in terms of the electromagnetic enhancement mechanism and charge transfer resonance process.

4-Hydroxyphenylacetic acid oxidation in sulfate and real olive oil mill wastewater by electrochemical advanced processes with a boron-doped diamond anode.

PubMed

Flores, Nelly; Cabot, Pere Lluís; Centellas, Francesc; Garrido, José Antonio; Rodríguez, Rosa María; Brillas, Enric; Sirés, Ignasi

2017-01-05

The degradation of 4-hydroxyphenylacetic acid, a ubiquitous component of olive oil mill wastewater (OOMW), has been studied by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed in either a 0.050M Na 2 SO 4 solution or a real OOMW at pH 3.0, using a cell with a boron-doped diamond (BDD) anode and an air-diffusion cathode for H 2 O 2 generation. Hydroxyl radicals formed at the BDD surface from water oxidation in all processes and/or in the bulk from Fenton's reaction between added Fe 2+ and generated H 2 O 2 in EF and PEF were the main oxidants. In both matrices, the oxidation ability of the processes increased in the order AO-H 2 O 2

Magnetic Enzymatic Platform for Organophosphate Pesticide Detection Using Boron-doped Diamond Electrodes.

PubMed

Pino, Flavio; Ivandini, Tribidasari A; Nakata, Kazuya; Fujishima, Akira; Merkoçi, Arben; Einaga, Yasuaki

2015-01-01

A simple and reliable enzymatic system for organophosporus pesticide detection was successfully developed, by exploiting the synergy between the magnetic beads collection capacity and the outstanding electrochemistry property of boron-doped diamond electrodes. The determination of an organophosphate pesticide, chlorpyrifos (CPF), was performed based on the inhibition system of the enzyme acetylcholinesterase bonded to magnetic beads through a biotin-streptavidin complex system. A better sensitivity was found for a system with magnetic beads in the concentration range of 10(-9) to 10(-5) M. The estimated limits of detection based on IC10 (10% acetylcholinesterase (AChE) inhibition) have been detected and optimized to be 5.7 × 10(-10) M CPF. Spiked samples of water of Yokohama (Japan) have been measured to validate the efficiency of the enzymatic system. The results suggested that the use of magnetic beads to immobilize biomolecules or biosensing agents is suitable to maintain the superiority of BDD electrodes.

Highly sensitive electrochemical biosensor for bisphenol A detection based on a diazonium-functionalized boron-doped diamond electrode modified with a multi-walled carbon nanotube-tyrosinase hybrid film.

PubMed

Zehani, Nedjla; Fortgang, Philippe; Saddek Lachgar, Mohamed; Baraket, Abdoullatif; Arab, Madjid; Dzyadevych, Sergei V; Kherrat, Rochdi; Jaffrezic-Renault, Nicole

2015-12-15

A highly sensitive electrochemical biosensor for the detection of Bisphenol A (BPA) in water has been developed by immobilizing tyrosinase onto a diazonium-functionalized boron doped diamond electrode (BDD) modified with multi-walled carbon nanotubes (MWCNTs). The fabricated biosensor exhibits excellent electroactivity towards o-quinone, a product of this enzymatic reaction of BPA oxidation catalyzed by tyrosinase. The developed BPA biosensor displays a large linear range from 0.01 nM to 100 nM, with a detection limit (LOD) of 10 pM. The feasibility of the proposed biosensor has been demonstrated on BPA spiked water river samples. Therefore, it could be a promising and reliable analytical tool for on-site monitoring of BPA in waste water. Copyright © 2015 Elsevier B.V. All rights reserved.

Application and stability of cathodes with manganese dioxide nanoflowers supported on Vulcan by Fenton systems for the degradation of RB5 azo dye.

PubMed

Aveiro, L R; Da Silva, A G M; Candido, E G; Antonin, V S; Parreira, L S; Papai, R; Gaubeur, I; Silva, Fernando L; Lanza, M R V; Camargo, P H C; Santos, M C

2018-05-21

This work describes the electrochemical degradation of Reactive Black 5 (RB5) by two methods: electrochemical and photo-assisted electrochemical degradation with and without a Fenton reagent. Two anodes were used, Pt and boron-doped diamond (BDD, 2500 ppm), and the cathode was 3% MnO 2 nanoflowers (NFMnO 2 ) on a carbon gas diffusion electrode (GDE). An electrochemical cell without a divider with a GDE with 3% w/w NFMnO 2 /C supported on carbon Vulcan XC72 was used. The decolorization efficiency was monitored by UV-vis spectroscopy, and the degradation was monitored by Total Organic Carbon (TOC) analysis. For dissolution monitoring, aliquots (1 mL) were collected during the degradation. After 6 h of H 2 O 2 electrogeneration, the manganese concentration in the RB5 solution was only 23.1 ± 1.2 μg L -1 . It was estimated that approximately 60 μg L -1 (<0.2%) of manganese migrated from the GDE to the solution after 12 h of electrolysis, which indicated the good stability of the GDE. The photoelectro-Fenton-BDD (PEF-BDD) processes showed both the best color removal percentage (∼93%) and 91% of mineralization. The 3% NFMnO 2 /C GDE is promising for RB5 degradation. Copyright © 2018. Published by Elsevier Ltd.

Zero Liquid Discharge approach in plating industry: treatment of degreasing effluents by electrocoagulation and anodic oxidation.

PubMed

Hermon, S; Grange, D; Pellet, Y; Lloret, G; Oyonarte, S; Bosch, F; Coste, M

2008-01-01

Degreasing waste effluents issued from a surface treatment plant were treated by electrochemical techniques in an attempt to reduce COD so that clean water can be returned to the rinse bath. Electrocoagulation, both with iron and aluminium anodes, and anodic oxidation with boron doped diamond (BDD) anodes were tested. In the electrocoagulation tests, the nature of the anodes did not impact significantly the reduction of COD. Electrocoagulation showed good COD removal rates, superior to 80%, but it was not able to reduce COD down to low levels. Anodic oxidation was able to reduce COD down to discharge limits; the oxidation efficiency was superior to 50%. Economical calculations show that anodic oxidation is best used as a polishing step after electrocoagulation. The bulk of the COD would be reduced by electrocoagulation and, then, anodic oxidation would reduce COD below discharge limits. The maximum treatable flow is somewhat hindered by the small sizes of current BDD installation but it would reach 600 m(3)/year if anodic oxidation is coupled with electrocoagulation, the operational cost being 2.90 Euros /m(3). (c) IWA Publishing 2008.

Coupling of solar photoelectro-Fenton with a BDD anode and solar heterogeneous photocatalysis for the mineralization of the herbicide atrazine.

PubMed

Garza-Campos, Benjamín R; Guzmán-Mar, Jorge Luis; Reyes, Laura Hinojosa; Brillas, Enric; Hernández-Ramírez, Aracely; Ruiz-Ruiz, Edgar J

2014-02-01

Here, the synergetic effect of coupling solar photoelectro-Fenton (SPEF) and solar heterogeneous photocatalysis (SPC) on the mineralization of 200mL of a 20mg L(-1) atrazine solution, prepared from the commercial herbicide Gesaprim, at pH 3.0 was studied. Uniform, homogeneous and adherent anatase-TiO2 films onto glass spheres of 5mm diameter were prepared by the sol-gel dip-coating method and used as catalyst for SPC. However, this procedure yielded a poor removal of the substrate because of the low oxidation ability of positive holes and OH formed at the catalyst surface to destroy it. Atrazine decay was improved using anodic oxidation (AO), electro-Fenton (EF), SPEF and coupled SPEF-SPC at 100mA. The electrolytic cell contained a boron-doped diamond (BDD) anode and H2O2 was generated at a BDD cathode fed with an air flow. The removal and mineralization of atrazine increased when more oxidizing agents were generated in the sequence AO

YBa2Cu3O7 thin films on nanocrystalline diamond films for HTSC bolometer

NASA Technical Reports Server (NTRS)

Cui, G.; Beetz, C. P., Jr.; Boerstler, R.; Steinbeck, J.

1993-01-01

Superconducting YBa2Cu3O(7-x) films on nanocrystalline diamond thin films have been fabricated. A composite buffer layer system consisting of diamond/Si3N4/YSZ/YBCO was explored for this purpose. The as-deposited YBCO films were superconducting with Tc of about 84 K and a relatively narrow transition width of about 8 K. SEM cross sections of the films showed very sharp interfaces between diamond/Si3N4 and between Si3N4/YSZ. The deposited YBCO film had a surface roughness of about 1000 A, which is suitable for high-temperature superconductive (HTSC) bolometer fabrication. It was also found that preannealing of the nanocrystalline diamond thin films at high temperature was very important for obtaining high-quality YBCO films.

Diamond Thin-Film Thermionic Generator

NASA Astrophysics Data System (ADS)

Clewell, J. M.; Ordonez, C. A.; Perez, J. M.

1997-03-01

Since the eighteen-hundreds scientists have sought to develop the highest thermal efficiency in heat engines such as thermionic generators. Modern research in the emerging diamond film industry has indicated the work functions of diamond thin-films can be much less than one electron volt, compelling fresh investigation into their capacity as thermionic generators and inviting new methodology for determining that efficiency. Our objective is to predict the efficiency of a low-work-function, degenerate semiconductor (diamond film) thermionic generator operated as a heat engine between two constant-temperature thermal reservoirs. Our presentation will focus on a theoretical model which predicts the efficiency of the system by employing a Monte Carlo computational technique from which we report results for the thermal efficiency and the thermionic current densities of diamond thin-films.

Electrolyte selection and microbial toxicity for electrochemical oxidative water treatment using a boron-doped diamond anode to support site specific contamination incident response.

PubMed

Phillips, Rebecca B; James, Ryan R; Magnuson, Matthew L

2018-04-01

Intentional and unintentional contamination incidents, such as terrorist attacks, natural disasters, and accidental spills, can result in large volumes of contaminated water. These waters may require pre-treatment before disposal and assurances that treated waters will not adversely impact biological processes at wastewater treatment facilities, or receiving waters. Based on recommendations of an industrial workgroup, this study addresses such concerns by studying electrochemical advanced oxidation process (EAOP) pre-treatment for contaminated waters, using a boron-doped diamond (BDD) anode, prior to discharge to wastewater treatment facilities. Reaction conditions were investigated, and microbial toxicity was assessed using the Microtox ® toxicity assay and the Nitrification Inhibition test. A range of contaminants were studied including herbicides, pesticides, pharmaceuticals and flame retardants. Resulting toxicities varied with supporting electrolyte from 5% to 92%, often increasing, indicating that microbial toxicity, in addition to parent compound degradation, should be monitored during treatment. These toxicity results are particularly novel because they systematically compare the microbial toxicity effects of a variety of supporting electrolytes, indicating some electrolytes may not be appropriate in certain applications. Further, these results are the first known report of the use of the Nitrification Inhibition test for this application. Overall, these results systematically demonstrate that anodic oxidation using the BDD anode is useful for addressing water contaminated with refractory organic contaminants, while minimizing impacts to wastewater plants or receiving waters accepting EAOP-treated effluent. The results of this study indicate nitrate can be a suitable electrolyte for incident response and, more importantly, serve as a baseline for site specific EAOP usage. Copyright © 2018 Elsevier Ltd. All rights reserved.

The In Situ Observation of Epitaxial Diamond Thin Film Nucleation and Growth Using Emission Electron Microscopy

DTIC Science & Technology

1993-12-01

diamond carbon on diamond Measurements of CVD diamond grown directly on Mo TEM specimen grids were made through a collaboration with the Fritz Haber ...Hawaii, May 1993. 2. --- , University of Illinois at Chicago, March 1993. 3. --- , Fritz Haber Institute, Berlin, June 1993. 3.0 Appendix: 8 1 Real...University, Athens OH 45701 -2979 *Permanent address: Fritz Haber Institute, Berlin, Germany. Thin (1Onm) carbon films are found to adhere to Chemical Vapor

Theoretical analysis of SAW propagation characteristics in (100) oriented AlN/diamond structure.

PubMed

Ro, Ruyen; Chiang, Yuan-Feng; Sung, Chia-Chi; Lee, Ruyue; Wu, Sean

2010-01-01

In this study, the finite element method is employed to calculate SAW characteristics in (100) AlN/diamond based structures with different electrical interfaces; i.e., IDT/ AlN/diamond, AlN/IDT/diamond, IDT/AlN/thin metal film/ diamond, and thin metal film/AlN/IDT/diamond. The effects of Cu and Al electrodes as well as the thickness of electrode on phase velocity, coupling coefficient, and reflectivity of SAWs are illustrated. Propagation characteristics of SAWs in (002) AlN/diamond-based structures are also presented for comparison. Simulation results show that to retain a large reflectivity for the design of RF filters and duplexers, the Cu IDT/(100) AlN/diamond structure possesses the highest phase velocity and largest coupling coefficient at the smallest AlN film thickness- to-wavelength ratio.

Design and investigation of properties of nanocrystalline diamond optical planar waveguides.

PubMed

Prajzler, Vaclav; Varga, Marian; Nekvindova, Pavla; Remes, Zdenek; Kromka, Alexander

2013-04-08

Diamond thin films have remarkable properties comparable with natural diamond. Because of these properties it is a very promising material for many various applications (sensors, heat sink, optical mirrors, chemical and radiation wear, cold cathodes, tissue engineering, etc.) In this paper we report about design, deposition and measurement of properties of optical planar waveguides fabricated from nanocrystalline diamond thin films. The nanocrystalline diamond planar waveguide was deposited by microwave plasma enhanced chemical vapor deposition and the structure of the deposited film was studied by scanning electron microscopy and Raman spectroscopy. The design of the presented planar waveguides was realized on the bases of modified dispersion equation and was schemed for 632.8 nm, 964 nm, 1 310 nm and 1 550 nm wavelengths. Waveguiding properties were examined by prism coupling technique and it was found that the diamond based planar optical element guided one fundamental mode for all measured wavelengths. Values of the refractive indices of our NCD thin film measured at various wavelengths were almost the same as those of natural diamond.

Electrochemical treatment of cetrimonium chloride with boron-doped diamond anodes. A technical and economical approach.

PubMed

de Araújo, Brenda R S; Linares León, José J

2018-05-15

This study presents the results of the electrochemical degradation of the emulsifier cetrimonium chloride (CTAC) on a boron-doped diamond (BDD) anode under different current densities and flow rates. Higher values of these parameters result in a more rapid removal. Nevertheless, operation at low current reduces the required applied charge and increases the chemical oxygen demand (COD) removal efficiency, as there is less development of ineffective parasitic reactions. On the other hand, high flow rates reduce the required volumetric applied charge and increase the COD removal current efficiency. In order to assist and enrich the study, an economic analysis has been performed. For short expected plant lifespans, operation at low current is advantageous due to the lower investment required, whereas for longer expected lifespans, the operational costs make the lower current densities less costly. High flow rates are always advantageous from a financial point of view. Copyright © 2018 Elsevier Ltd. All rights reserved.

Electro-oxidation of the dye azure B: kinetics, mechanism, and by-products.

PubMed

Olvera-Vargas, Hugo; Oturan, Nihal; Aravindakumar, C T; Paul, M M Sunil; Sharma, Virender K; Oturan, Mehmet A

2014-01-01

In this work, the electrochemical degradation of the dye azure B in aqueous solutions was studied by electrochemical advanced oxidation processes (EAOPs), electro-Fenton, and anodic oxidation processes, using Pt/carbon-felt and boron-doped diamond (BDD)/carbon-felt cells with H₂O₂ electrogeneration. The higher oxidation power of the electro-Fenton (EF) process using BDD anode was demonstrated. The oxidative degradation of azure B by the electrochemically generated hydroxyl radicals ((•)OH) follows a pseudo-first-order kinetics. The apparent rate constants of the oxidation of azure B by (•)OH were measured according to pseudo-first-order kinetic model. The absolute rate constant of azure B hydroxylation reaction was determined by competition kinetics method and found to be 1.19 × 10(9) M(-1) s(-1). It was found that the electrochemical degradation of the dye leads to the formation of aromatic by-products which are then oxidized to aliphatic carboxylic acids before their almost mineralization to CO₂ and inorganic ions (sulfate, nitrate, and ammonium). The evolution of the TOC removal and time course of short-chain carboxylic acids during treatment were also investigated.

Performance of electrochemical oxidation and photocatalysis in terms of kinetics and energy consumption. New insights into the p-cresol degradation.

PubMed

Escudero, Carlos J; Iglesias, Olalla; Dominguez, Sara; Rivero, Maria J; Ortiz, Inmaculada

2017-06-15

This work reports the comparative performance of two Advanced Oxidation Processes (AOPs), electrochemical oxidation and photocatalysis, as individual technological alternatives for the treatment of effluents containing p-cresol. First, the influence of operating parameters in the oxidation and mineralization yield was carried out together with kinetic analysis. Boron Doped Diamond (BDD), RuO 2 and Pt as anodic materials, Na 2 SO 4 and NaCl as supporting electrolytes and different current densities were evaluated in electrochemical oxidation whereas the effect of TiO 2 concentration and radiation was studied in the photocatalytic degradation. Then, the parameter Electrical Energy per Order (E EO ) was calculated to compare the energy consumption in both AOPs, concluding that under the studied conditions the electrochemical treatment with BDD, Na 2 SO 4 and 125 A m -2 showed the best energy efficiency, with an E EO of 5.83 kW h m -3 order -1 for p-cresol and 58.05 kW h m -3 order -1 for DOC removal, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Thermally stable diamond brazing

DOEpatents

Radtke, Robert P [Kingwood, TX

2009-02-10

A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

Surface smoothening effects on growth of diamond films

NASA Astrophysics Data System (ADS)

Reshi, Bilal Ahmad; Kumar, Shyam; Kartha, Moses J.; Varma, Raghava

2018-04-01

We have carried out a detailed study of the growth dynamics of the diamond film during initial time on diamond substrates. The diamond films are deposited using Microwave Plasma Chemical Vapor Deposition (MPCVD) method for different times. Surface morphology and its correlation with the number of hours of growth of thin films was invested using atomic force microscopy (AFM). Diamond films have smooth interface with average roughness of 48.6873nm. The initial growth dynamics of the thin film is investigated. Interestingly, it is found that there is a decrease in the surface roughness of the film. Thus a smoothening effect is observed in the grown films. The film enters into the growth regime in the later times. Our results also find application in building diamond detector.

A compact Nd:YAG DPSSL using diamond-cooled technology

NASA Astrophysics Data System (ADS)

Chou, Hsian P.; Wang, Yu-Lin; Hasson, Victor H.; Trainor, Daniel W.

2005-03-01

In our diamond-cooled approach, thin disks of laser gain material, e.g., Nd:YAG, are alternated between thin disks of single crystal synthetic diamond whose heat conductivity is over 2000 W/m-°K. The gain medium is face-pumped (along the optical axis) by the output of laser diode arrays. This optical configuration produces heat transfer from Nd:YAG to the diamond, in the direction of the optical axis, and then heat is rapidly conducted radially outward through the diamond to the cooling fluid circulating at the circumference of the diamond/YAG assembly. This geometry effectively removes the heat from the gain material in a manner that permits the attainment of high power output with excellent beam quality.

Compositional and structural analysis of nitrogen incorporated and ion implanted diamond thin films

NASA Astrophysics Data System (ADS)

Garratt, Elias James

Significant progress in area of nano-structured thin film systems has taken place in recent decades. In particular, diamond thin film systems are being widely studied for their wear resistant, optical and electronic properties. Of the various methods researchers use to modify the structure of such films, three techniques in particular are of interest due to their versatility: modification of the growth atmosphere, growth on metalized substrates, providing an interfacial layer, and modification through post-growth ion implantation. The aim of this study is to investigate the effects each has to the structure and composition of elements. Different techniques are applied in each section; nitrogen gas dilution in a microwave plasma CVD system, diamond deposition on a metal interfacial layer and ion implantation in thin nanocrystalline diamond film. The forms of nanocrystalline diamond film resulting from such modifications are investigated using advanced spectroscopic and spectrometric techniques, as well as mechanical testing and surface mapping. The impact of these characterizations will provide valuable perspective to researchers in materials science. Understanding the changes to the structure and properties of this class of thin films, which can be induced through various mechanisms, will allow future researchers to refine these films towards technological applications in areas of hard coatings, electronics and photonics.

Obsessive-compulsive disorder versus body dysmorphic disorder: a comparison study of two possibly related disorders.

PubMed

Phillips, Katharine A; Pinto, Anthony; Menard, William; Eisen, Jane L; Mancebo, Maria; Rasmussen, Steven A

2007-01-01

The relationship between obsessive-compulsive disorder (OCD) and body dysmorphic disorder (BDD) is unclear. BDD has been proposed to be an OCD-spectrum disorder or even a type of OCD. However, few studies have directly compared these disorders' clinical features. We compared characteristics of subjects with OCD (n=210), BDD (n=45), and comorbid BDD/OCD (n=40). OCD and BDD did not significantly differ in terms of demographic features, age of OCD or BDD onset, illness duration, and many other variables. However, subjects with BDD had significantly poorer insight than those with OCD and were more likely to be delusional. Subjects with BDD were also significantly more likely than those with OCD to have lifetime suicidal ideation, as well as lifetime major depressive disorder and a lifetime substance use disorder. The comorbid BDD/OCD group evidenced greater morbidity than subjects with OCD or BDD in a number of domains, but differences between the comorbid BDD/OCD group and the BDD group were no longer significant after controlling for BDD severity. However, differences between the comorbid BDD/OCD group and the OCD group remained significant after controlling for OCD severity. In summary, OCD and BDD did not significantly differ on many variables but did have some clinically important differences. These findings have implications for clinicians and for the classification of these disorders. (c) 2006 Wiley-Liss, Inc.

Electrochemical oxidation of bio-refractory dye in a simulated textile industry effluent using DSA electrodes in a filter-press type FM01-LC reactor.

PubMed

Rodríguez, Francisca A; Mateo, María N; Aceves, Juan M; Rivero, Eligio P; González, Ignacio

2013-01-01

This work presents a study on degradation of indigo carmine dye in a filter-press type FM01-LC reactor using Sb2O5-doped Ti/IrO2-SnO2 dimensionally stable anode (DSA) electrodes. Micro- and macroelectrolysis studies were carried out using solutions of 0.8 mM indigo carmine in 0.05 M NaCl, which resemble blue denim laundry industrial wastewater. Microelectrolysis results show the behaviour of DSA electrodes in comparison with the behaviour of boron-doped diamond (BDD) electrodes. In general, dye degradation reactions are carried out indirectly through active chlorine generated on DSA, whereas in the case of BDD electrodes more oxidizing species are formed, mainly OH radicals, on the electrode surface. The well-characterized geometry, flow pattern and mass transport of the FM01-LC reactor used in macroelectrolysis experiments allowed the evaluation of the effect of hydrodynamic conditions on the chlorine-mediated degradation rate. Four values of Reynolds number (Re) (93, 371, 464 and 557) at four current densities (50, 100, 150 and 200 A/m2) were tested. The results show that the degradation rate is independent of Re at low current density (50 A/m2) but becomes dependent on the Re at high current density (200 A/m2). This behaviour shows the central role of mass transport and the reactor parameters and design. The low energy consumption (2.02 and 9.04 kWh/m3 for complete discolouration and chemical oxygen demand elimination at 50 A/m2, respectively) and the low cost of DSA electrodes compared to BDD make DSA electrodes promising for practical application in treating industrial textile effluents. In the present study, chlorinated organic compounds were not detected.

Application of electrochemical advanced oxidation processes to the mineralization of the herbicide diuron.

PubMed

Pipi, Angelo R F; Sirés, Ignasi; De Andrade, Adalgisa R; Brillas, Enric

2014-08-01

Here, solutions with 0.185mM of the herbicide diuron of pH 3.0 have been treated by electrochemical advanced oxidation processes (EAOPs) like electrochemical oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF) or solar PEF (SPEF). Trials were performed in stirred tank reactors of 100mL and in a recirculation flow plant of 2.5L using a filter-press reactor with a Pt or boron-doped diamond (BDD) anode and an air-diffusion cathode for H2O2 electrogeneration. Oxidant hydroxyl radicals were formed from water oxidation at the anode and/or in the bulk from Fenton's reaction between added Fe(2+) and generated H2O2. In both systems, the relative oxidation ability of the EAOPs increased in the sequence EO-H2O2

Synthesis and electrochemical detection of a thiazolyl-indole natural product isolated from the nosocomial pathogen Pseudomonas aeruginosa.

PubMed

Buzid, Alyah; Muimhneacháin, Eoin Ó; Reen, F Jerry; Hayes, Phyllis E; Pardo, Leticia M; Shang, Fengjun; O'Gara, Fergal; Sperry, Jonathan; Luong, John H T; Glennon, Jeremy D; McGlacken, Gerard P

2016-09-01

Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen, capable of surviving in a broad range of natural environments and quickly acquiring resistance. It is associated with hospital-acquired infections, particularly in patients with compromised immunity, and is the primary cause of morbidity and mortality in cystic fibrosis (CF) patients. P. aeruginosa is also of nosocomial importance on dairy farms and veterinary hospitals, where it is a key morbidity factor in bovine mastitis. P. aeruginosa uses a cell-cell communication system consisting of signalling molecules to coordinate bacterial secondary metabolites, biofilm formation, and virulence. Simple and sensitive methods for the detection of biomolecules as indicators of P. aeruginosa infection would be of great clinical importance. Here, we report the synthesis of the P. aeruginosa natural product, barakacin, which was recently isolated from the bovine ruminal strain ZIO. A simple and sensitive electrochemical method was used for barakacin detection using a boron-doped diamond (BDD) and glassy carbon (GC) electrodes, based on cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The influence of electrolyte pH on the peak potential and peak currents was also investigated. At pH 2.0, the peak current was linearly dependent on barakacin concentration (in the range used, 1-10 μM), with correlation coefficients greater than 0.98 on both electrodes. The detection limit (S/N = 3) on the BDD electrode was 100-fold lower than that obtained on the GC electrode. The optimized method using the BDD electrode was extended to bovine (cow feces) and human (sputum of a CF patient) samples. Spiked barakacin was easily detected in these matrices at a limit of 0.5 and 0.05 μM, respectively. Graphical abstract Electrochemical detection of barakacin.

Rhenium Alloys as Ductile Substrates for Diamond Thin-Film Electrodes.

PubMed

Halpern, Jeffrey M; Martin, Heidi B

2014-02-01

Molybdenum-rhenium (Mo/Re) and tungsten-rhenium (W/Re) alloys were investigated as substrates for thin-film, polycrystalline boron-doped diamond electrodes. Traditional, carbide-forming metal substrates adhere strongly to diamond but lose their ductility during exposure to the high-temperature (1000°C) diamond, chemical vapor deposition environment. Boron-doped semi-metallic diamond was selectively deposited for up to 20 hours on one end of Mo/Re (47.5/52.5 wt.%) and W/Re (75/25 wt.%) alloy wires. Conformal diamond films on the alloys displayed grain sizes and Raman signatures similar to films grown on tungsten; in all cases, the morphology and Raman spectra were consistent with well-faceted, microcrystalline diamond with minimal sp 2 carbon content. Cyclic voltammograms of dopamine in phosphate-buffered saline (PBS) showed the wide window and low baseline current of high-quality diamond electrodes. In addition, the films showed consistently well-defined, dopamine electrochemical redox activity. The Mo/Re substrate regions that were uncoated but still exposed to the diamond-growth environment remained substantially more flexible than tungsten in a bend-to-fracture rotation test, bending to the test maximum of 90° and not fracturing. The W/Re substrates fractured after a 27° bend, and the tungsten fractured after a 21° bend. Brittle, transgranular cleavage fracture surfaces were observed for tungsten and W/Re. A tension-induced fracture of the Mo/Re after the prior bend test showed a dimple fracture with a visible ductile core. Overall, the Mo/Re and W/Re alloys were suitable substrates for diamond growth. The Mo/Re alloy remained significantly more ductile than traditional tungsten substrates after diamond growth, and thus may be an attractive metal substrate for more ductile, thin-film diamond electrodes.

Rhenium Alloys as Ductile Substrates for Diamond Thin-Film Electrodes

PubMed Central

Halpern, Jeffrey M.; Martin, Heidi B.

2014-01-01

Molybdenum-rhenium (Mo/Re) and tungsten-rhenium (W/Re) alloys were investigated as substrates for thin-film, polycrystalline boron-doped diamond electrodes. Traditional, carbide-forming metal substrates adhere strongly to diamond but lose their ductility during exposure to the high-temperature (1000°C) diamond, chemical vapor deposition environment. Boron-doped semi-metallic diamond was selectively deposited for up to 20 hours on one end of Mo/Re (47.5/52.5 wt.%) and W/Re (75/25 wt.%) alloy wires. Conformal diamond films on the alloys displayed grain sizes and Raman signatures similar to films grown on tungsten; in all cases, the morphology and Raman spectra were consistent with well-faceted, microcrystalline diamond with minimal sp2 carbon content. Cyclic voltammograms of dopamine in phosphate-buffered saline (PBS) showed the wide window and low baseline current of high-quality diamond electrodes. In addition, the films showed consistently well-defined, dopamine electrochemical redox activity. The Mo/Re substrate regions that were uncoated but still exposed to the diamond-growth environment remained substantially more flexible than tungsten in a bend-to-fracture rotation test, bending to the test maximum of 90° and not fracturing. The W/Re substrates fractured after a 27° bend, and the tungsten fractured after a 21° bend. Brittle, transgranular cleavage fracture surfaces were observed for tungsten and W/Re. A tension-induced fracture of the Mo/Re after the prior bend test showed a dimple fracture with a visible ductile core. Overall, the Mo/Re and W/Re alloys were suitable substrates for diamond growth. The Mo/Re alloy remained significantly more ductile than traditional tungsten substrates after diamond growth, and thus may be an attractive metal substrate for more ductile, thin-film diamond electrodes. PMID:25404788

Modular cognitive-behavioral therapy for body dysmorphic disorder: a randomized controlled trial.

PubMed

Wilhelm, Sabine; Phillips, Katharine A; Didie, Elizabeth; Buhlmann, Ulrike; Greenberg, Jennifer L; Fama, Jeanne M; Keshaviah, Aparna; Steketee, Gail

2014-05-01

There are few effective treatments for body dysmorphic disorder (BDD) and a pressing need to develop such treatments. We examined the feasibility, acceptability, and efficacy of a manualized modular cognitive-behavioral therapy for BDD (CBT-BDD). CBT-BDD utilizes core elements relevant to all BDD patients (e.g., exposure, response prevention, perceptual retraining) and optional modules to address specific symptoms (e.g., surgery seeking). Thirty-six adults with BDD were randomized to 22 sessions of immediate individual CBT-BDD over 24 weeks (n=17) or to a 12-week waitlist (n=19). The Yale-Brown Obsessive-Compulsive Scale Modified for BDD (BDD-YBOCS), Brown Assessment of Beliefs Scale, and Beck Depression Inventory-II were completed pretreatment, monthly, posttreatment, and at 3- and 6-month follow-up. The Sheehan Disability Scale and Client Satisfaction Inventory (CSI) were also administered. Response to treatment was defined as ≥30% reduction in BDD-YBOCS total from baseline. By week 12, 50% of participants receiving immediate CBT-BDD achieved response versus 12% of waitlisted participants (p=0.026). By posttreatment, 81% of all participants (immediate CBT-BDD plus waitlisted patients subsequently treated with CBT-BDD) met responder criteria. While no significant group differences in BDD symptom reduction emerged by Week 12, by posttreatment CBT-BDD resulted in significant decreases in BDD-YBOCS total over time (d=2.1, p<0.0001), with gains maintained during follow-up. Depression, insight, and disability also significantly improved. Patient satisfaction was high, with a mean CSI score of 87.3% (SD=12.8%) at posttreatment. CBT-BDD appears to be a feasible, acceptable, and efficacious treatment that warrants more rigorous investigation. Copyright © 2014. Published by Elsevier Ltd.

Associations in the longitudinal course of body dysmorphic disorder with major depression, obsessive-compulsive disorder, and social phobia.

PubMed

Phillips, Katharine A; Stout, Robert L

2006-06-01

Body dysmorphic disorder (BDD) is an impairing and relatively common disorder that has high comorbidity with certain Axis I disorders. However, the longitudinal associations between BDD and comorbid disorders have not previously been examined. Such information may shed light on the nature of BDD's relationship to putative "near-neighbor" disorders, such as major depression, obsessive-compulsive disorder (OCD), and social phobia. This study examined time-varying associations between BDD and these comorbid disorders in 161 participants over 1-3 years of follow-up in the first prospective longitudinal study of the course of BDD. We found that BDD had significant longitudinal associations with major depression--that is, change in the status of BDD and major depression was closely linked in time, with improvement in major depression predicting BDD remission, and, conversely, improvement in BDD predicting depression remission. We also found that improvement in OCD predicted BDD remission, but that BDD improvement did not predict OCD remission. No significant longitudinal associations were found for BDD and social phobia (although the results for analyses of OCD and social phobia were less numerically stable). These findings suggest (but do not prove) that BDD may be etiologically linked to major depression and OCD, i.e., that BDD may be a member of both the putative OCD spectrum and the affective spectrum. However, BDD does not appear to simply be a symptom of these comorbid disorders, as BDD symptoms persisted in a sizable proportion of subjects who remitted from these comorbid disorders. Additional studies are needed to elucidate the nature of BDD's relationship to commonly co-occurring disorders, as this issue has important theoretical and clinical implications.

Subthreshold body dysmorphic disorder in adolescents: Prevalence and impact.

PubMed

Schneider, Sophie C; Mond, Jonathan; Turner, Cynthia M; Hudson, Jennifer L

2017-05-01

The aim of the current study was to establish the prevalence of subthreshold body dysmorphic disorder (subthreshold-BDD) in a community sample of adolescents, and to compare disorder correlates in individuals with subthreshold-BDD to those with probable full-syndrome BDD (probable-BDD) and those without BDD (non-BDD). Self-report questionnaires assessing DSM-IV BDD criteria, past mental health service use, and symptoms of body dysmorphic disorder, anxiety, depression, obsessive-compulsive disorder and eating disorders, were completed by 3149 Australian high school students (mean age =14.6 years, 63.5% male). Male participants also completed measures assessing quality of life, muscularity concerns, emotional symptoms, conduct problems, hyperactivity, and peer problems. The prevalence of subthreshold-BDD was 3.4%, and probable-BDD was 1.7%. Compared to the non-BDD group, subthreshold-BDD was associated with elevated symptoms of comorbid psychopathology and greater past mental health service use, and in male-only measures, with poorer quality of life and elevated muscularity concerns. Subthreshold-BDD participants reported significantly lower mental health service use, and fewer symptoms of depression, eating disorders, and hyperactivity than probable-BDD participants, however, other comorbid symptoms did not differ significantly between these groups. These findings indicate that subthreshold-BDD is associated with substantial difficulties for adolescents in the general community. BDD screening should include subthreshold presentations, as these may be an important target for early intervention programs. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Changes in the cutting efficiency of different types of dental diamond rotary instrument with repeated cuts and disinfection.

PubMed

Bae, Jin-Hyuk; Yi, Jaeyoung; Kim, Sungtae; Shim, June-Sung; Lee, Keun-Woo

2014-01-01

Cutting efficiency is one of the most important factors to consider when a specific dental diamond rotary instrument is selected. However, the selection of a dental diamond rotary instrument is based on clinical experience rather than any scientific evidence. The purpose of this study was to identify how the cutting efficiency of different types of dental diamond rotary instrument changed with repeated cuts and disinfection. Four types of diamond rotary instrument from 2 dental manufacturers (Shofu, Jin Dental) were investigated with a high-speed air-turbine handpiece. The groups were as follows: S cham group (n=10): chamfer design from Shofu; J cham group (n=10): chamfer design from Jin Dental; S thin group (n=10): thin tapered design from Shofu; J thin group (n=10): thin tapered design from Jin Dental. Changes in the cutting efficiency of diamond rotary instruments on glass ceramic blocks were measured after repeated cuts. Changes in cutting efficiency also were measured for 30 diamond rotary instruments, the same type as those used in group J cham after disinfection with ethylene oxide gas, immersion in solution, or autoclaving. One-way ANOVA, 2-way ANOVA, and repeated-measures ANOVA were used to identify differences in cutting efficiency, in total cutting efficiency, and change trend in cutting efficiency (α=.05). The Tukey honestly significant difference method was used for the post hoc tests. The principal metal components of the diamond rotary instruments were detected with x-ray spectrometry. The mean (standard deviation [SD]) total cutting efficiency after 10 cuts in the 4 groups was in the following order: J cham group (0.210 ± 0.064 g/min) > S cham group (0.170 ± 0.064 g/min) > J thin group (0.130 ± 0.042 g/min) > S thin group (0.010 ± 0.040 g/min) (P<.05).The decrease in the cutting efficiency was greatest after the first cut. The cutting efficiency was not influenced by repeated disinfection. The cutting efficiencies of diamond rotary instruments with different designs and particle sizes showed a decreasing trend after repeated cuts but did not show any change after various disinfecting procedures. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Morphological Transition in Diamond Thin-Films Induced by Boron in a Microwave Plasma Deposition Process.

PubMed

Baker, Paul A; Goodloe, David R; Vohra, Yogesh K

2017-11-14

The purpose of this study is to understand the basic mechanisms responsible for the synthesis of nanostructured diamond films in a microwave plasma chemical vapor deposition (MPCVD) process and to identify plasma chemistry suitable for controlling the morphology and electrical properties of deposited films. The nanostructured diamond films were synthesized by MPCVD on Ti-6Al-4V alloy substrates using H₂/CH₄/N₂ precursor gases and the plasma chemistry was monitored by the optical emission spectroscopy (OES). The synthesized thin-films were characterized by x -ray diffraction and scanning electron microscopy. The addition of B₂H₆ to the feedgas during MPCVD of diamond thin-films changes the crystal grain size from nanometer to micron scale. Nanostructured diamond films grown with H₂/CH₄/N₂ gases demonstrate a broad (111) Bragg x -ray diffraction peak (Full-Width at Half-Maximum (FWHM) = 0.93° 2θ), indicating a small grain size, whereas scans show a definite sharpening of the diamond (111) peak (FWHM = 0.30° 2θ) with the addition of boron. OES showed a decrease in CN (carbon-nitrogen) radical in the plasma with B₂H₆ addition to the gas mixture. Our study indicates that CN radical plays a critical role in the synthesis of nanostructured diamond films and suppression of CN radical by boron-addition in the plasma causes a morphological transition to microcrystalline diamond.

Diamond thin films: giving biomedical applications a new shine

PubMed Central

Nistor, P. A.

2017-01-01

Progress made in the last two decades in chemical vapour deposition technology has enabled the production of inexpensive, high-quality coatings made from diamond to become a scientific and commercial reality. Two properties of diamond make it a highly desirable candidate material for biomedical applications: first, it is bioinert, meaning that there is minimal immune response when diamond is implanted into the body, and second, its electrical conductivity can be altered in a controlled manner, from insulating to near-metallic. In vitro, diamond can be used as a substrate upon which a range of biological cells can be cultured. In vivo, diamond thin films have been proposed as coatings for implants and prostheses. Here, we review a large body of data regarding the use of diamond substrates for in vitro cell culture. We also detail more recent work exploring diamond-coated implants with the main targets being bone and neural tissue. We conclude that diamond emerges as one of the major new biomaterials of the twenty-first century that could shape the way medical treatment will be performed, especially when invasive procedures are required. PMID:28931637

Development of a templated approach to fabricate diamond patterns on various substrates.

PubMed

Shimoni, Olga; Cervenka, Jiri; Karle, Timothy J; Fox, Kate; Gibson, Brant C; Tomljenovic-Hanic, Snjezana; Greentree, Andrew D; Prawer, Steven

2014-06-11

We demonstrate a robust templated approach to pattern thin films of chemical vapor deposited nanocrystalline diamond grown from monodispersed nanodiamond (mdND) seeds. The method works on a range of substrates, and we herein demonstrate the method using silicon, aluminum nitride (AlN), and sapphire substrates. Patterns are defined using photo- and e-beam lithography, which are seeded with mdND colloids and subsequently introduced into microwave assisted chemical vapor deposition reactor to grow patterned nanocrystalline diamond films. In this study, we investigate various factors that affect the selective seeding of different substrates to create high quality diamond thin films, including mdND surface termination, zeta potential, surface treatment, and plasma cleaning. Although the electrostatic interaction between mdND colloids and substrates is the main process driving adherence, we found that chemical reaction (esterification) or hydrogen bonding can potentially dominate the seeding process. Leveraging the knowledge on these different interactions, we optimize fabrication protocols to eliminate unwanted diamond nucleation outside the patterned areas. Furthermore, we have achieved the deposition of patterned diamond films and arrays over a range of feature sizes. This study contributes to a comprehensive understanding of the mdND-substrate interaction that will enable the fabrication of integrated nanocrystalline diamond thin films for microelectronics, sensors, and tissue culturing applications.

All diamond self-aligned thin film transistor

DOEpatents

Gerbi, Jennifer [Champaign, IL

2008-07-01

A substantially all diamond transistor with an electrically insulating substrate, an electrically conductive diamond layer on the substrate, and a source and a drain contact on the electrically conductive diamond layer. An electrically insulating diamond layer is in contact with the electrically conductive diamond layer, and a gate contact is on the electrically insulating diamond layer. The diamond layers may be homoepitaxial, polycrystalline, nanocrystalline or ultrananocrystalline in various combinations.A method of making a substantially all diamond self-aligned gate transistor is disclosed in which seeding and patterning can be avoided or minimized, if desired.

Associations in the Longitudinal Course of Body Dysmorphic Disorder with Major Depression, Obsessive Compulsive Disorder, and Social Phobia

PubMed Central

Phillips, Katharine A.; Stout, Robert L.

2009-01-01

Body dysmorphic disorder (BDD) is an impairing and relatively common disorder that has high comorbidity with certain Axis I disorders. However, the longitudinal associations between BDD and comorbid disorders have not previously been examined. Such information may shed light on the nature of BDD’s relationship to putative “near-neighbor” disorders, such as major depression, obsessive-compulsive disorder (OCD), and social phobia. This study examined time-varying associations between BDD and these comorbid disorders in 161 participants over 1 to 3 years of follow-up in the first prospective longitudinal study of the course of BDD. We found that BDD had significant longitudinal associations with major depression – that is, change in the status of BDD and major depression were closely linked in time, with improvement in major depression predicting BDD remission, and, conversely, improvement in BDD predicting depression remission. We also found that improvement in OCD predicted BDD remission, but that BDD improvement did not predict OCD remission. No significant longitudinal associations were found for BDD and social phobia (although the results for analyses of OCD and social phobia were less numerically stable). These findings suggest (but do not prove) that BDD may be etiologically linked to major depression and OCD – i.e., that BDD may be a member of both the putative OCD spectrum and the affective spectrum. However, BDD does not appear to simply be a symptom of these comorbid disorders, as BDD symptoms persisted in a sizable proportion of subjects who remitted from these comorbid disorders. Additional studies are needed to elucidate the nature of BDD’s relationship to commonly co-occurring disorders, as this issue has important theoretical and clinical implications. PMID:16309706

Importance of Electrode Material in the Electrochemical Treatment of Wastewater Containing Organic Pollutants

NASA Astrophysics Data System (ADS)

Panizza, Marco

Electrochemical oxidation is a promising method for the treatment of wastewaters containing organic compounds. As a general rule, the electrochemical incineration of organics at a given electrode can take place at satisfactory rates and without electrode deactivation only at high anodic potentials in the region of the water discharge due to the participation of the intermediates of oxygen evolution. The nature of the electrode material strongly influences both the selectivity and the efficiency of the process. In particular, anodes with low oxygen evolution overpotential (i.e., good catalysts for oxygen evolution reactions), such as graphite, IrO2, RuO2, and Pt only permit the partial oxidation of organics, while anodes with high oxygen evolution overpotential (i.e., anodes that are poor catalysts for oxygen evolution reactions), such as SnO2, PbO2, and boron-doped diamond (BDD) favor the complete oxidation of organics to CO2 and so are ideal electrodes for wastewater treatment.However, the application of SnO2 and PbO2 anodes may be limited by their short service life and the risk of lead contamination, while BDD electrodes exhibit good chemical and electrochemical stability, a long life, and a wide potential window for water discharge, and are thus promising anodes for industrial-scale wastewater treatment.

Removal of artificial sweetener aspartame from aqueous media by electrochemical advanced oxidation processes.

PubMed

Lin, Heng; Oturan, Nihal; Wu, Jie; Sharma, Virender K; Zhang, Hui; Oturan, Mehmet A

2017-01-01

The degradation and mineralization of aspartame (ASP) in aqueous solution were investigated, for the first time, by electrochemical advanced oxidation processes (EAOPs) in which hydroxyl radicals were formed concomitantly in the bulk from Fenton reaction via in situ electrogenerated Fenton's reagent and at the anode surface from the water oxidation. Experiments were performed in an undivided cylindrical glass cell with a carbon-felt cathode and a Pt or boron-doped diamond (BDD) anode. The effect of Fe 2+ concentration and applied current on the degradation and mineralization kinetics of ASP was evaluated. The absolute rate constant for the reaction between ASP and OH was determined as (5.23 ± 0.02) × 10 9  M -1  s -1 by using the competition kinetic method. Almost complete mineralization of ASP was achieved with BDD anode at 200 mA constant current electrolysis. The formation and generation of the formed carboxylic acids (as ultimate end products before complete mineralization) and released inorganic ion were monitored by ion-exclusion high performance liquid chromatography (HPLC) and ion chromatography techniques, respectively. The global toxicity of the treated ASP solution during treatment was assessed by the Microtox ® method using V. fischeri bacteria luminescence inhibition. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lindane degradation by electrooxidation process: Effect of electrode materials on oxidation and mineralization kinetics.

PubMed

Dominguez, Carmen M; Oturan, Nihal; Romero, Arturo; Santos, Aurora; Oturan, Mehmet A

2018-05-15

This study focuses on the effect of electrode materials on abatement of lindane (an organochlorine pesticide) by electrooxidation process. Comparative performances of different anodic (platinum (Pt), dimensionally stable anode (DSA) and boron-doped diamond (BDD)) and cathodic (carbon sponge (CS), carbon felt (CF) and stainless steel (SS)) materials on lindane electrooxidation and mineralization were investigated. Special attention was paid to determine the role of chlorine active species during the electrooxidation process. The results showed that better performances were obtained when using a BDD anode and CF cathode cell. The influence of the current density was assessed to optimize the oxidation of lindane and the mineralization of its aqueous solution. A quick (10 min) and complete oxidation of 10 mg L -1 lindane solution and relatively high mineralization degree (80% TOC removal) at 4 h electrolysis were achieved at 8.33 mA cm -2 current density. Lindane was quickly oxidized by in-situ generated hydroxyl radicals, (M( • OH)), formed from oxidation of water on the anode (M) surface following pseudo first-order reaction kinetics. Formation of chlorinated and hydroxylated intermediates and carboxylic acids during the treatment were identified and a plausible mineralization pathway of lindane by hydroxyl radicals was proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Body Dysmorphic Disorder Symptom Scale: Development and preliminary validation of a self-report scale of symptom specific dysfunction.

PubMed

Wilhelm, Sabine; Greenberg, Jennifer L; Rosenfield, Elizabeth; Kasarskis, Irina; Blashill, Aaron J

2016-06-01

The Body Dysmorphic Disorder Symptom Scale (BDD-SS) is a new self-report measure used to examine the severity of a wide variety of symptoms associated with body dysmorphic disorder (BDD). The BDD-SS was designed to differentiate, for each group of symptoms, the number of symptoms endorsed and their severity. This report evaluates and compares the psychometric characteristics of the BDD-SS in relation to other measures of BDD, body image, and depression in 99 adult participants diagnosed with BDD. Total scores of the BDD-SS showed good reliability and convergent validity and moderate discriminant validity. Analyses of the individual BDD-SS symptom groups confirmed the reliability of the checking, grooming, weight/shape, and cognition groups. The current findings indicate that the BDD-SS can be quickly administered and used to examine the severity of heterogeneous BDD symptoms for research and clinical purposes. Copyright © 2016. Published by Elsevier Ltd.

Electrochemical DNA biosensor based on the BDD nanograss array electrode.

PubMed

Jin, Huali; Wei, Min; Wang, Jinshui

2013-04-10

The development of DNA biosensor has attracted considerable attention due to their potential applications, including gene analysis, clinical diagnostics, forensic study and more medical applications. Using electroactive daunomycin as an indicator, the hybridization detection was measured by differential pulse voltammetry in this study. Electrochemical DNA biosensor was developed based on the BDD film electrode (fBDD) and BDD nanograss array electrode (nBDD). In comparison with fBDD and AuNPs/CA/fBDD electrode, the lower semicircle diameter of electrochemical impedance spectroscopy obtained on nBDD and AuNPs/CA/nBDD electrode indicated that the presence of nanograss array improved the reactive site, reduced the interfacial resistance, and made the electron transfer easier. Using electroactive daunomycin as an indicator, the hybridization detection was measured by differential pulse voltammetry. The experimental results demonstrated that the prepared AuNPs/CA/nBDD electrode was suitable for DNA hybridization with favorable performance of faster response, higher sensitivity, lower detection limit and satisfactory selectivity, reproducibility and stability.

Electrochemical DNA biosensor based on the BDD nanograss array electrode

PubMed Central

2013-01-01

Background The development of DNA biosensor has attracted considerable attention due to their potential applications, including gene analysis, clinical diagnostics, forensic study and more medical applications. Using electroactive daunomycin as an indicator, the hybridization detection was measured by differential pulse voltammetry in this study. Results Electrochemical DNA biosensor was developed based on the BDD film electrode (fBDD) and BDD nanograss array electrode (nBDD). In comparison with fBDD and AuNPs/CA/fBDD electrode, the lower semicircle diameter of electrochemical impedance spectroscopy obtained on nBDD and AuNPs/CA/nBDD electrode indicated that the presence of nanograss array improved the reactive site, reduced the interfacial resistance, and made the electron transfer easier. Using electroactive daunomycin as an indicator, the hybridization detection was measured by differential pulse voltammetry. Conclusions The experimental results demonstrated that the prepared AuNPs/CA/nBDD electrode was suitable for DNA hybridization with favorable performance of faster response, higher sensitivity, lower detection limit and satisfactory selectivity, reproducibility and stability. PMID:23575250

Body dysmorphic disorder symptoms and risk for suicide: The role of depression.

PubMed

Shaw, A M; Arditte Hall, K A; Rosenfield, E; Timpano, K R

2016-12-01

Body dysmorphic disorder (BDD) is associated with elevated suicidality. Little is known about why BDD patients are at increased risk. The interpersonal-psychological theory of suicide (IPTS) could clarify suicidality in BDD, and theorizes that perceived burdensomeness and thwarted belongingness lead to suicidal desire, while an acquired capability for suicide is necessary to attempt suicide. No study has investigated how BDD symptoms relate to IPTS constructs or mediators of the relationship between BDD and suicidality. Individuals (N=235) enrolled in Amazon.com's Mechanical Turk (MTurk), who had appearance concerns, completed questionnaires about BDD, depression, eating pathology, and suicide risk. MTurk is an online data collection platform in which participants complete surveys for payment. BDD symptoms predicted suicidal desire, but not acquired capability for suicide. Depression mediated the relationship between BDD and suicidal desire. Research should examine how fluctuations in BDD affect suicide risk. Replication in a clinical sample may inform treatments for BDD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electrochemical oxidation of ampicillin antibiotic at boron-doped diamond electrodes and process optimization using response surface methodology.

PubMed

Körbahti, Bahadır K; Taşyürek, Selin

2015-03-01

Electrochemical oxidation and process optimization of ampicillin antibiotic at boron-doped diamond electrodes (BDD) were investigated in a batch electrochemical reactor. The influence of operating parameters, such as ampicillin concentration, electrolyte concentration, current density, and reaction temperature, on ampicillin removal, COD removal, and energy consumption was analyzed in order to optimize the electrochemical oxidation process under specified cost-driven constraints using response surface methodology. Quadratic models for the responses satisfied the assumptions of the analysis of variance well according to normal probability, studentized residuals, and outlier t residual plots. Residual plots followed a normal distribution, and outlier t values indicated that the approximations of the fitted models to the quadratic response surfaces were very good. Optimum operating conditions were determined at 618 mg/L ampicillin concentration, 3.6 g/L electrolyte concentration, 13.4 mA/cm(2) current density, and 36 °C reaction temperature. Under response surface optimized conditions, ampicillin removal, COD removal, and energy consumption were obtained as 97.1 %, 92.5 %, and 71.7 kWh/kg CODr, respectively.

Synthesis of thin films in boron-carbon-nitrogen ternary system by microwave plasma enhanced chemical vapor deposition

NASA Astrophysics Data System (ADS)

Kukreja, Ratandeep Singh

The Boron Carbon Nitorgen (B-C-N) ternary system includes materials with exceptional properties such as wide band gap, excellent thermal conductivity, high bulk modulus, extreme hardness and transparency in the optical and UV range that find application in most fields ranging from micro-electronics, bio-sensors, and cutting tools to materials for space age technology. Interesting materials that belong to the B-C-N ternary system include Carbon nano-tubes, Boron Carbide, Boron Carbon Nitride (B-CN), hexagonal Boron Nitride ( h-BN), cubic Boron Nitride (c-BN), Diamond and beta Carbon Nitride (beta-C3N4). Synthesis of these materials requires precisely controlled and energetically favorable conditions. Chemical vapor deposition is widely used technique for deposition of thin films of ceramics, metals and metal-organic compounds. Microwave plasma enhanced chemical vapor deposition (MPECVD) is especially interesting because of its ability to deposit materials that are meta-stable under the deposition conditions, for e.g. diamond. In the present study, attempt has been made to synthesize beta-carbon nitride (beta-C3N4) and cubic-Boron Nitride (c-BN) thin films by MPECVD. Also included is the investigation of dependence of residual stress and thermal conductivity of the diamond thin films, deposited by MPECVD, on substrate pre-treatment and deposition temperature. Si incorporated CNx thin films are synthesized and characterized while attempting to deposit beta-C3N4 thin films on Si substrates using Methane (CH4), Nitrogen (N2), and Hydrogen (H2). It is shown that the composition and morphology of Si incorporated CNx thin film can be tailored by controlling the sequence of introduction of the precursor gases in the plasma chamber. Greater than 100mum size hexagonal crystals of N-Si-C are deposited when Nitrogen precursor is introduced first while agglomerates of nano-meter range graphitic needles of C-Si-N are deposited when Carbon precursor is introduced first in the deposition chamber. Hexagonal -- BN thin films are successfully deposited using Diborane (B2H6) (5% in H2), Ammonia (NH3) and H2 as precursor gases in the conventional MPECVD mode with and without the negative DC bias. The quality of h-BN in the films improved with pressure and when NH3 used as the first precursor gas in the deposition chamber. c-BN thin films are successfully deposited using Boron-Trifluoride (BF3) (10% in Argon (Ar)), N2, H2, Ar and Helium (He) gases in the electron cyclotron resonance (ECR) mode of the MPECVD system with negative DC bias. Up-to 66% c-BN in the films is achieved under deposition conditions of lower gas flow rates and higher deposition pressures than that reported in the literature for film deposited by ECR-MPECVD. It is shown that the percentage c-BN in the films correlates with the deposition pressure, BF3/H2 ratio and, negative DC bias during nucleation and growth. Diamond thin films are deposited using 60%Ar, 39% H2 and, 1%CH4 at 600°C, 700°C and 800°C substrate temperatures, measured by an IR pyrometer, on Si substrates pre-treated with 3-6nm diamond sol and 20-40mum diamond slurry. Raman spectroscopy, FTIR, X-Ray diffraction (XRD) and, photo-thermal reflectivity methods are used to characterize the thin films. Residual stresses observed for the diamond thin films deposited in this study are tensile in nature and increased with deposition temperature. Better quality diamond films with lower residual stresses are obtained for films deposited on Si substrate pre-treated with 3-6nm diamond sol. Preliminary results on thermal conductivity, k, suggest that k is directly dependent on the deposition temperature and independent of substrate pre-treatment signifying that the nano-seeding technique can be used to replace conventional surface activation technique for diamond seeding where needed.

Sulfate-mediated electrooxidation of X-ray contrast media on boron-doped diamond anode.

PubMed

Radjenovic, Jelena; Petrovic, Mira

2016-05-01

Recently, electrochemical activation of sulfate ions to sulfate radical species and nonradically activated persulfate has been demonstrated at boron-doped diamond (BDD) anode, which enhanced the electrooxidation kinetics of several persistent contaminants. In this study, we investigated the transformation pathways of two X-ray contrast media (ICM), diatrizoate and iopromide, in electrooxidation at BDD anode using sulfate and inert nitrate anolyte. Sulfate anolyte yielded a seven-fold increase in apparent rate constants for ICM oxidation compared to inert nitrate anolyte, and a two-fold increase for the removal of organic carbon. Higher iodine release was observed in electrooxidation of diatrizoate compared to iopromide. In the case of diatrizoate, around 80% of deiodination efficiency was achieved in both anolytes. Deiodination efficiency of iopromide was somewhat lower in nitrate anolyte (≤75%) and significantly reduced in sulfate anolyte (≤46%) due to a larger steric hindrance of alkyl side chains. Moreover, a considerable lag phase of iopromide deiodination was observed in sulfate anolyte, indicating that initial oxidation reactions took place almost exclusively at the alkyl side chains. Several transformation products (TPs) of ICM were identified in electrooxidation in sulfate anolyte, and only three TPs in the case of nitrate anolyte. The main mechanistic steps in the oxidation of iopromide were H-abstraction and bond cleavage in the alkyl side chains. Diatrizoate was mainly transformed through oxidative cleavage of iodine substituent and inter-molecular cyclization. Two hydroxylamine derivatives of iopromide and a nitro-derivative of diatrizoate were observed in sulfate anolyte. These products have not been reported previously for hydroxyl radical-mediated oxidation of ICM. Given that electron-transfer mechanism is more typical for sulfate than for hydroxyl radicals, formation of hydroxylamine and nitro-derivatives of ICM was assigned to one-electron charge transfer to sulfate radical species and formation of N-centered radicals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Charge multiplication effect in thin diamond films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skukan, N., E-mail: nskukan@irb.hr; Grilj, V.; Sudić, I.

2016-07-25

Herein, we report on the enhanced sensitivity for the detection of charged particles in single crystal chemical vapour deposition (scCVD) diamond radiation detectors. The experimental results demonstrate charge multiplication in thin planar diamond membrane detectors, upon impact of 18 MeV O ions, under high electric field conditions. Avalanche multiplication is widely exploited in devices such as avalanche photo diodes, but has never before been reproducibly observed in intrinsic CVD diamond. Because enhanced sensitivity for charged particle detection is obtained for short charge drift lengths without dark counts, this effect could be further exploited in the development of sensors based on avalanchemore » multiplication and radiation detectors with extreme radiation hardness.« less

Therapist-guided, Internet-based cognitive–behavioural therapy for body dysmorphic disorder (BDD-NET): a feasibility study

PubMed Central

Enander, Jesper; Ivanov, Volen Z; Andersson, Erik; Mataix-Cols, David; Ljótsson, Brjánn; Rück, Christian

2014-01-01

Objectives Cognitive–behavioural therapy (CBT) is an effective treatment for body dysmorphic disorder (BDD). However, most sufferers do not have access to this treatment. One way to increase access to CBT is to administer treatment remotely via the Internet. This study piloted a novel therapist-supported, Internet-based CBT program for BDD (BDD-NET). Design Uncontrolled clinical trial. Participants Patients (N=23) were recruited through self-referral and assessed face to face at a clinic specialising in obsessive–compulsive and related disorders. Suitable patients were offered secure access to BDD-NET. Intervention BDD-NET is a 12-week treatment program based on current psychological models of BDD that includes psychoeducation, functional analysis, cognitive restructuring, exposure and response prevention, and relapse prevention modules. A dedicated therapist provides active guidance and feedback throughout the entire process. Main outcome measure The clinician-administered Yale-Brown Obsessive Compulsive Scale for BDD (BDD-YBOCS). Symptom severity was assessed pretreatment, post-treatment and at the 3-month follow-up. Results BDD-NET was deemed highly acceptable by patients and led to significant improvements on the BDD-YBOCS (p=<0.001) with a large within-group effect size (Cohen's d=2.01, 95% CI 1.05 to 2.97). At post-treatment, 82% of the patients were classified as responders (defined as≥30% improvement on the BDD-YBOCS). These gains were maintained at the 3-month follow-up. Secondary outcome measures of depression, global functioning and quality of life also showed significant improvements with moderate to large effect sizes. On average, therapists spent 10 min per patient per week providing support. Conclusions The results suggest that BDD-NET has the potential to greatly increase access to CBT, at least for low-risk individuals with moderately severe BDD symptoms and reasonably good insight. A randomised controlled trial of BDD-NET is warranted. Trial registration number Clinicaltrials.gov registration ID NCT01850433. PMID:25256187

Prevalence of Body Dysmorphic Disorder Symptoms and Body Weight Concerns in Patients Seeking Abdominoplasty.

PubMed

Brito, Maria José Azevedo de; Nahas, Fábio Xerfan; Cordás, Táki Athanássios; Gama, Maria Gabriela; Sucupira, Eduardo Rodrigues; Ramos, Tatiana Dalpasquale; Felix, Gabriel de Almeida Arruda; Ferreira, Lydia Masako

2016-03-01

Body dysmorphic disorder (BDD) is one of the most common psychiatric conditions found in patients seeking cosmetic surgery, and body contouring surgery is most frequently sought by patients with BDD. To estimate the prevalence and severity of BDD symptoms in patients seeking abdominoplasty. Ninety patients of both sexes were preoperatively divided into two groups: patients with BDD symptoms (n = 51) and those without BDD symptoms (n = 39) based both on the Body Dysmorphic Disorder Examination (BDDE) and clinical assessment. Patients in the BDD group were classified as having mild to moderate or severe symptoms, according to the BDDE. Body weight and shape concerns were assessed using the Body Shape Questionnaire (BSQ). The prevalence of BDD symptoms was 57%. There were significant associations between BDD symptoms and degree of body dissatisfaction, level of preoccupation with physical appearance, and avoidance behaviors. Mild to moderate and severe symptoms of BDD were present in 41% and 59% of patients, respectively, in the BDD group. It was found that the more severe the symptoms of BDD, the higher the level of concern with body weight and shape (P < .001). Patients having distorted self-perception of body shape, or distorted comparative perception of body image were respectively 3.67 or 5.93 times more likely to show more severe symptoms of BDD than those with a more accurate perception. Candidates for abdominoplasty had a high prevalence of BDD symptoms, and body weight and shape concerns were associated with increased symptom severity. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

Cognitive-Behavioral Therapy for Adolescent Body Dysmorphic Disorder: A Pilot Study.

PubMed

Greenberg, Jennifer L; Mothi, Suraj Sarvode; Wilhelm, Sabine

2016-03-01

Body dysmorphic disorder (BDD) is a relatively common and severe disorder that typically onsets in adolescence, but often goes unrecognized. Despite BDD's severity and early onset, treatment outcome research on adolescent BDD is scarce. Cognitive-behavioral therapy is the gold-standard psychosocial treatment for BDD in adults and has shown promise in adolescents. The current study examined the development and testing of a new CBT for adolescents with BDD. We tested feasibility, acceptability, and treatment outcome in a sample of 13 adolescents (mean age 15.23years, range: 13-17) with primary BDD. Treatment was delivered in 12-22 weekly individual sessions. Standardized clinician ratings and self-report measures were used to assess BDD and related symptoms pre- and posttreatment and at 3- and 6-months follow-up. At posttreatment, BDD and related symptoms (e.g., insight, mood) were significantly improved. Scores on the Yale-Brown Obsessive Compulsive Scale for BDD indicated a 50% (intent-to-treat) and 68% (completer) improvement in BDD symptoms. Seventy-five percent of adolescents who started treatment and 100% of completers were considered treatment responders. Treatment gains were maintained at follow-up. High patient satisfaction ratings and patient feedback indicated that treatment was acceptable. This represents the largest study of a psychosocial treatment for adolescent BDD. Copyright © 2015. Published by Elsevier Ltd.

Piezoelectric actuated micro-resonators based on the growth of diamond on aluminum nitride thin films.

PubMed

Hees, J; Heidrich, N; Pletschen, W; Sah, R E; Wolfer, M; Williams, O A; Lebedev, V; Nebel, C E; Ambacher, O

2013-01-18

Unimorph heterostructures based on piezoelectric aluminum nitride (AlN) and diamond thin films are highly desirable for applications in micro- and nanoelectromechanical systems. In this paper, we present a new approach to combine thin conductive boron-doped as well as insulating nanocrystalline diamond (NCD) with sputtered AlN films without the need for any buffer layers between AlN and NCD or polishing steps. The zeta potentials of differently treated nanodiamond (ND) particles in aqueous colloids are adjusted to the zeta potential of AlN in water. Thereby, the nucleation density for the initial growth of diamond on AlN can be varied from very low (10(8) cm(-2)), in the case of hydrogen-treated ND seeding particles, to very high values of 10(11) cm(-2) for oxidized ND particles. Our approach yielding high nucleation densities allows the growth of very thin NCD films on AlN with thicknesses as low as 40 nm for applications such as microelectromechanical beam resonators. Fabricated piezo-actuated micro-resonators exhibit enhanced mechanical properties due to the incorporation of boron-doped NCD films. Highly boron-doped NCD thin films which replace the metal top electrode offer Young's moduli of more than 1000 GPa.

A molecular epidemiology of treponemes in beef cattle digital dermatitis lesions and comparative analyses with sheep contagious ovine digital dermatitis and dairy cattle digital dermatitis lesions.

PubMed

Sullivan, L E; Evans, N J; Blowey, R W; Grove-White, D H; Clegg, S R; Duncan, J S; Carter, S D

2015-07-09

Bovine digital dermatitis (BDD) is an infective foot disease commonly reported in dairy cattle where Treponema are considered as the primary causative infectious agents. There still remains little definitive information on the etiology of BDD in beef cattle suggesting further investigations are warranted. Beef BDD lesions (n=34) and healthy beef foot tissues (n=38) were analysed by PCR for three BDD-associated Treponema phylogroups and also for Dichelobacter nodosus and Fusobacterium necrophorum. Spirochete culture was attempted on all BDD lesion samples. One or more BDD-associated Treponema phylogroups were detected in 100% of beef BDD lesions. "Treponema medium/Treponema vincentii-like", "Treponema phagedenis-like" and Treponema pedis spirochetes were identified in 27/34 (79%), 31/34 (91%) and 24/34 (71%) of BDD lesions, respectively. No BDD-associated treponeme DNA was amplified from beef healthy foot tissues. D. nodosus and F. necrophorum were present in 24/34 (71%) and 15/34 (44%) of lesions and 10/38 (26%) and 12/38 (32%) of healthy foot tissues, respectively. Twenty spirochetes were isolated from beef BDD lesions; 19 were representatives of the three BDD-associated Treponema phylogroups. One spirochete isolate shared less than 97% 16S rRNA gene similarity to the three cultivable BDD-associated Treponema phylogroups and therefore may represent a novel taxa of Treponema. Upon comparison, sheep contagious ovine digital dermatitis (CODD), dairy cattle and beef cattle BDD lesions appear to have extremely similar bacteriological data and therefore provides evidence of a shared etiopathogenesis posing concerns for cross-species transmission. Copyright © 2015 Elsevier B.V. All rights reserved.

Scalable Fabrication of Integrated Nanophotonic Circuits on Arrays of Thin Single Crystal Diamond Membrane Windows.

PubMed

Piracha, Afaq H; Rath, Patrik; Ganesan, Kumaravelu; Kühn, Stefan; Pernice, Wolfram H P; Prawer, Steven

2016-05-11

Diamond has emerged as a promising platform for nanophotonic, optical, and quantum technologies. High-quality, single crystalline substrates of acceptable size are a prerequisite to meet the demanding requirements on low-level impurities and low absorption loss when targeting large photonic circuits. Here, we describe a scalable fabrication method for single crystal diamond membrane windows that achieves three major goals with one fabrication method: providing high quality diamond, as confirmed by Raman spectroscopy; achieving homogeneously thin membranes, enabled by ion implantation; and providing compatibility with established planar fabrication via lithography and vertical etching. On such suspended diamond membranes we demonstrate a suite of photonic components as building blocks for nanophotonic circuits. Monolithic grating couplers are used to efficiently couple light between photonic circuits and optical fibers. In waveguide coupled optical ring resonators, we find loaded quality factors up to 66 000 at a wavelength of 1560 nm, corresponding to propagation loss below 7.2 dB/cm. Our approach holds promise for the scalable implementation of future diamond quantum photonic technologies and all-diamond photonic metrology tools.

X-Ray Absorption near Edge Structure Spectroscopy of Nanodiamonds from the Allende Meteorite

NASA Technical Reports Server (NTRS)

Flynn, G. J.; Keller, L. P.; Hill, H.; Jacobsen, C.; Wirick, S.

2000-01-01

Carbon X-ray Absorption Near Edge Structure Spectroscopy shows Allende DM nanodiamonds have two pre-edge peaks, consistent with other small diamonds, but fail to show a diamond exciton which is seen in 3.6 nm diamond thin films.

Grating-assisted coupling to nanophotonic circuits in microcrystalline diamond thin films.

PubMed

Rath, Patrik; Khasminskaya, Svetlana; Nebel, Christoph; Wild, Christoph; Pernice, Wolfram Hp

2013-01-01

Synthetic diamond films can be prepared on a waferscale by using chemical vapour deposition (CVD) on suitable substrates such as silicon or silicon dioxide. While such films find a wealth of applications in thermal management, in X-ray and terahertz window design, and in gyrotron tubes and microwave transmission lines, their use for nanoscale optical components remains largely unexplored. Here we demonstrate that CVD diamond provides a high-quality template for realizing nanophotonic integrated optical circuits. Using efficient grating coupling devices prepared from partially etched diamond thin films, we investigate millimetre-sized optical circuits and achieve single-mode waveguiding at telecoms wavelengths. Our results pave the way towards broadband optical applications for sensing in harsh environments and visible photonic devices.

Diamond drumhead crystals for X-ray optics applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolodziej, Tomasz; Vodnala, Preeti; Terentyev, Sergey

2016-07-14

Thin (<50 µm) and flawless diamond single crystals are essential for the realization of numerous advanced X-ray optical devices at synchrotron radiation and free-electron laser facilities. The fabrication and handling of such ultra-thin components without introducing crystal damage and strain is a challenge. Drumhead crystals, monolithic crystal structures composed of a thin membrane furnished with a surrounding solid collar, are a solution ensuring mechanically stable strain-free mounting of the membranes with efficient thermal transport. Diamond, being one of the hardest and most chemically inert materials, poses significant difficulties in fabrication. Reported here is the successful manufacture of diamond drumhead crystalsmore » in the [100] orientation using picosecond laser milling. Subsequent high-temperature treatment appears to be crucial for the membranes to become defect free and unstrained, as revealed by X-ray topography on examples of drumhead crystals with a 26 µm thick (1 mm in diameter) and a 47 µm thick (1.5 × 2.5 mm) membrane.« less

A Review of Body Dysmorphic Disorder and Its Presentation in Different Clinical Settings

PubMed Central

Mufaddel, Amir; Osman, Ossama T.; Almugaddam, Fadwa

2013-01-01

Objective: Body dysmorphic disorder (BDD) is a relatively common psychiatric disorder characterized by preoccupations with perceived defects in physical appearance. This review aimed to explore epidemiology, clinical features, comorbidities, and treatment options for BDD in different clinical settings. Data Source and Study Selection: A search of the literature from 1970 to 2011 was performed using the MEDLINE search engine. English-language articles, with no restriction regarding the type of articles, were identified using the search terms body dysmorphic disorder, body dysmorphic disorder clinical settings, body dysmorphic disorder treatment, and body dysmorphic disorder & psychodermatology. Results: BDD occurs in 0.7% to 2.4% of community samples and 13% of psychiatric inpatients. Etiology is multifactorial, with recent findings indicating deficits in visual information processing. There is considerable overlap between BDD and obsessive-compulsive disorder (OCD) in symptom etiology and response to treatment, which has led to suggestions that BDD can be classified with anxiety disorders and OCD. A recent finding indicated genetic overlap between BDD and OCD. Over 60% of patients with BDD had a lifetime anxiety disorder, and 38% had social phobia, which tends to predate the onset of BDD. Studies reported a high level of comorbidity with depression and social phobia occurring in > 70% of patients with BDD. Individuals with BDD present frequently to dermatologists (about 9%–14% of dermatologic patients have BDD). BDD co-occurs with pathological skin picking in 26%–45% of cases. BDD currently has 2 variants: delusional and nondelusional, and both variants respond similarly to serotonin reuptake inhibitors (SRIs), which may have effect on obsessive thoughts and rituals. Cognitive-behavioral therapy has the best established treatment results. Conclusions: A considerable overlap exists between BDD and other psychiatric disorders such as OCD, anxiety, and delusional disorder, and this comorbidity should be considered in evaluation, management, and long-term follow-up of the disorder. Individuals with BDD usually consult dermatologists and cosmetic surgeons rather than psychiatrists. Collaboration between different specialties (such as primary care, dermatology, cosmetic surgery, and psychiatry) is required for better treatment outcome. PMID:24392251

Effects of an Appearance-Focused Interpretation Training Intervention on Eating Disorder Symptoms.

PubMed

Summers, Berta J; Cougle, Jesse R

2018-03-13

Previous research suggests that computerized interpretation bias modification (IBM) techniques may be useful for modifying thoughts and behaviours relevant to eating pathology; however, little is known about the utility of IBM for decreasing specific eating disorder (ED) symptoms (e.g. bulimia, drive for thinness). The current study sought to further examine the utility of IBM for ED symptoms via secondary analyses of an examination of IBM for individuals with elevated body dysmorphic disorder (BDD) symptoms (see Summers and Cougle, 2016), as these disorders are both characterized by threat interpretation biases of ambiguous appearance-related information. We recruited 41 participants for a randomized trial comparing four sessions of IBM aimed at modifying problematic social and appearance-related threat interpretation biases with a placebo control training (PC). At 1-week post-treatment, and relative to the PC, the IBM group reported greater reductions in negative/threat interpretations of ambiguous information in favour of positive/benign biases. Furthermore, among individuals with high pre-treatment bulimia symptoms, IBM yielded greater reductions in bulimia symptoms compared with PC at post-treatment. No treatment effects were observed on drive for thinness symptoms. The current study suggests that cognitive interventions for individuals with primary BDD symptoms may improve co-occurring ED symptoms such as bulimia.

[Body dysmorphic disorder].

PubMed

Grau, Katharina; Fegert, Jörg Michael; Allroggen, Marc

2015-01-01

Body dysmorphic disorder (BDD) is a relatively common disorder with a point prevalence of 0.7-2.4 %. BDD is characterized by the patient's excessive concern with an imagined or slight defect in physical appearance. BDD usually begins in adolescence. Comorbidity rates and also suicidality rates are high. The course of BDD tends to be chronic. According to the present state of knowledge, cognitive-behavioral therapy and pharmacotherapy with selective serotonin reuptake inhibitors are valuable options in the therapy of BDD. The case report describes a recent case of BDD with typical clinical and therapy-related characteristics. The aim of this work is to strengthen the awareness of BDD in clinical practice of child and adolescent psychiatry, facilitating an adequate diagnosis and treatment of the affected individuals.

Measurements and Studies of Secondary Electron Emission of Diamond Amplified Photocathode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu,Q.

2008-10-01

The Diamond Amplified Photocathode (DAP) is a novel approach to generating electrons. By following the primary electron beam, which is generated by traditional electron sources, with an amplifier, the electron beam available to the eventual application is increased by 1 to 2 orders of magnitude in current. Diamond has a very wide band gap of 5.47eV which allows for a good negative electron affinity with simple hydrogenation, diamond can hold more than 2000MV/m field before breakdown. Diamond also provides the best rigidity among all materials. These two characters offer the capability of applying high voltage across very thin diamond filmmore » to achieve high SEY and desired emission phase. The diamond amplifier also is capable of handling a large heat load by conduction and sub-nanosecond pulse input. The preparation of the diamond amplifier includes thinning and polishing, cleaning with acid etching, metallization, and hydrogenation. The best mechanical polishing available can provide high purity single crystal diamond films with no less than 100 {micro}m thickness and <15 nm Ra surface roughness. The ideal thickness for 700MHz beam is {approx}30 {micro}m, which requires further thinning with RIE or laser ablation. RIE can achieve atomic layer removal precision and roughness eventually, but the time consumption for this procedure is very significant. Laser ablation proved that with <266nm ps laser beam, the ablation process on the diamond can easily achieve removing a few microns per hour from the surface and <100nm roughness. For amplifier application, laser ablation is an adequate and efficient process to make ultra thin diamond wafers following mechanical polishing. Hydrogenation will terminate the diamond surface with monolayer of hydrogen, and form NEA so that secondary electrons in the conduction band can escape into the vacuum. The method is using hydrogen cracker to strike hydrogen atoms onto the bare diamond surface to form H-C bonds. Two independent experiments were carried out to determine the transport of the electrons within the diamond and their emission at the surface. In transmission mode measurements, the diamond amplifier was coated with metal on both sides, so results simply depend only on the electron transport within the diamond. The SEY for this mode provides one secondary electron per 20eV energy, which gives the gain of more than 200 for 4.7keV (effective energy) primary electrons under 2MV/m. Laser detrapping can help the signal maintain the gain with lops pulse and duty cycle of 1.67 x 10{sup -7}. In emission mode measurements, in which the diamond is prepared as in the actual application, the SEY is {approx}20 for 700eV (effective energy) primary electrons under 1.21MV/m. The electric field applied and the primary electron energy is limited by the experiment setup, but the results show good trend toward large gain under high field. Thermal emittance of the diamond secondary emission is critical for the beam application. A careful design is setup to measure with very fine precision and accuracy of 0.01eV.« less

Diamond heteroepitaxial lateral overgrowth

DOE PAGES

Tang, Y. -H.; Bi, B.; Golding, B.

2015-02-24

A method of diamond heteroepitaxial lateral overgrowth is demonstrated which utilizes a photolithographic metal mask to pattern a thin (001) epitaxial diamond surface. Significant structural improvement was found, with a threading dislocation density reduced by two orders of magnitude at the top surface of a thick overgrown diamond layer. In the initial stage of overgrowth, a reduction of diamond Raman linewidth in the overgrown area was also realized. Thermally-induced stress and internal stress were determined by Raman spectroscopy of adhering and delaminated diamond films. As a result, the internal stress is found to decrease as sample thickness increases.

Proceedings of the Seventh Applied Diamond Conference/Third Frontier Carbon Technology Joint Conference (ADC/FCT 2003). Supplement 1

NASA Technical Reports Server (NTRS)

Murakawa, M. (Editor); Miyoshi, K. (Editor); Koga, Y. (Editor); Schaefer, L. (Editor); Tzeng, Y. (Editor)

2003-01-01

This document contains 2 reports which were presented at the Seventh Applied Diamond Conference/Third Frontier Carbon Technology Joint Conference. The topics discuss the formation of C-N nanofibers as well as the characterization of diamond thin films.

Optimization of an integrated electrodisinfection/electrocoagulation process with Al bipolar electrodes for urban wastewater reclamation.

PubMed

Cotillas, Salvador; Llanos, Javier; Cañizares, Pablo; Mateo, Sara; Rodrigo, Manuel A

2013-04-01

In this work, a novel integrated electrochemical process for urban wastewater regeneration is described. The electrochemical cell consists in a Boron Doped Diamond (BDD) or a Dimensionally Stable Anode (DSA) as anode, a Stainless Steel (SS) as cathode and a perforated aluminum plate, which behaves as bipolar electrode, between anode and cathode. Thus, in this cell, it is possible to carry out, at the same time, two different electrochemical processes: electrodisinfection (ED) and electrocoagulation (EC). The treatment of urban wastewater with different anodes and different operating conditions is studied. First of all, in order to check the process performance, experiments with synthetic wastewaters were carried out, showing that it is possible to achieve a 100% of turbidity removal by the electrodissolution of the bipolar electrode. Next, the effect of the current density and the anode material are studied during the ED-EC process of actual effluents. Results show that it is possible to remove Escherichia coli and turbidity simultaneously of an actual effluent from a WasteWater Treatment Facility (WWTF). The use of BDD anodes allows to remove the E. coli completely at an applied electric charge of 0.0077 A h dm(-3) when working with a current density of 6.65 A m(-2). On the other hand, with DSA anodes, the current density necessary to achieve the total removal of E. coli is higher (11.12 A m(-2)) than that required with BDD anodes. Finally, the influence of cell flow path and flow rate have been studied. Results show that the performance of the process strongly depends on the characteristics of the initial effluent (E. coli concentration and Cl(-)/NH(4)(+) initial ratio) and that a cell configuration cathode (inlet)-anode (outlet) and a higher flow rate enhance the removal of the turbidity from the treated effluent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Electrocoagulation: Simply a Phase Separation Technology? The Case of Bronopol Compared to Its Treatment by EAOPs.

PubMed

Bocos, Elvira; Brillas, Enric; Sanromán, M Ángeles; Sirés, Ignasi

2016-07-19

Electrocoagulation (EC) has long been considered a phase separation process, well suited for industrial wastewater treatment since it causes a quick, drastic decay of organic matter content. This research demonstrates that EC also behaves, at least for some molecules like the industrial preservative bronopol, as an effective transformation technology able to yield several breakdown products. This finding has relevant environmental implications, pointing to EC as a greener process than described in literature. A thorough optimization of EC was performed with solutions of bronopol in a simulated water matrix, yielding the complete disappearance of the parent molecule within 20 min at 200 mA (∼20 mA/cm(2)), using Fe as the anode and cathode. A 25% of total organic carbon (TOC) abatement was attained as maximum, with bronopol being converted into bromonitromethane, bromochloromethane, formaldehyde and formic acid. N atoms were accumulated as NO3(-), whereas Br(-) was stable once released. This suggests that mediated oxidation by active chlorine, as well as by hydroxyl radicals resulting from its reaction with iron ions, is the main transformation mechanism. Aiming to enhance the mineralization, a sequential combination of EC with electro-Fenton (EF) as post-treatment process was proposed. EF with boron-doped diamond (BDD) anode ensured the gradual TOC removal under the action of (•)OH and BDD((•)OH), also transforming Br(-) into BrO3(-).

Prevalence and clinical characteristics of body dysmorphic disorder in an adult inpatient setting†

PubMed Central

Conroy, Michelle; Menard, William; Fleming-Ives, Kathryn; Modha, Poonam; Cerullo, Hilary; Phillips, Katharine A.

2008-01-01

Objective Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with an imagined or slight defect in appearance, is an often-severe, understudied disorder. We determined BDD’s prevalence and clinical features on a general adult psychiatric inpatient unit. To our knowledge, only one previous prevalence study has been done in this setting. Method One hundred patients completed 3 self-report measures: the Body Dysmorphic Disorder Questionnaire (BDD-Q), Beck Anxiety Inventory (BAI) and Center for Epidemiologic Studies Depression Scale (CES-D). Those who screened positive for BDD were interviewed to confirm DSM-IV BDD and its clinical features. Charts were reviewed for demographic and clinical information. Results BDD was diagnosed in 16.0% (95% CI=8.7–23.3%) (n=16) of patients. A high proportion of those with BDD reported that BDD symptoms contributed to suicidality. Patients revealed BDD symptoms to a mean of only 15.1%±33.7% lifetime mental health clinicians; only one (6.3%) reported symptoms to his current inpatient psychiatrist. Most did not disclose their symptoms due to embarrassment. Those with BDD were younger (P=.008) and had higher CES-D scores (P=.008). The two groups did not significantly differ on BAI score, demographic characteristics or discharge diagnoses. Conclusions BDD is relatively common but underdiagnosed in psychiatric inpatients and is associated with more severe depressive symptoms. PMID:18164943

Silicon solar cell performance deposited by diamond like carbon thin film ;Atomic oxygen effects;

NASA Astrophysics Data System (ADS)

Aghaei, Abbas Ail; Eshaghi, Akbar; Karami, Esmaeil

2017-09-01

In this research, a diamond-like carbon thin film was deposited on p-type polycrystalline silicon solar cell via plasma-enhanced chemical vapor deposition method by using methane and hydrogen gases. The effect of atomic oxygen on the functioning of silicon coated DLC thin film and silicon was investigated. Raman spectroscopy, field emission scanning electron microscopy, atomic force microscopy and attenuated total reflection-Fourier transform infrared spectroscopy were used to characterize the structure and morphology of the DLC thin film. Photocurrent-voltage characteristics of the silicon solar cell were carried out using a solar simulator. The results showed that atomic oxygen exposure induced the including oxidation, structural changes, cross-linking reactions and bond breaking of the DLC film; thus reducing the optical properties. The photocurrent-voltage characteristics showed that although the properties of the fabricated thin film were decreased after being exposed to destructive rays, when compared with solar cell without any coating, it could protect it in atomic oxygen condition enhancing solar cell efficiency up to 12%. Thus, it can be said that diamond-like carbon thin layer protect the solar cell against atomic oxygen exposure.

Classification of body dysmorphic disorder - what is the advantage of the new DSM-5 criteria?

PubMed

Schieber, Katharina; Kollei, Ines; de Zwaan, Martina; Martin, Alexandra

2015-03-01

In DSM-5 the diagnosis of body dysmorphic disorder (BDD) has been subjected to two important changes: Firstly, BDD has been assigned to the category of obsessive-compulsive and related disorders. Secondly, a new criterion has been defined requiring the presence of repetitive behaviors or mental acts in response to appearance concerns. The aims of this study were to report the prevalence rates of BDD based on a DSM-5 diagnosis, and to evaluate the impact of the recently introduced DSM-5 criteria for BDD by comparing the prevalence rates (DSM-5 vs. BDD-criteria (DSM-IV/DSM-5), dysmorphic concerns, and depressive symptoms, were assessed in a representative sample of the German general population (N=2129, aged 18-65years). The association between BDD case identification based on DSM-IV and DSM-5 was strong (Phi=.95, p<.001), although point prevalence of BDD according to DSM-5 was slightly lower (2.9%, n=62 vs. 3.2%, n=68). Approximately one third of the identified BDD (DSM-5) cases reported time-consuming behavioral acts in response to appearance concerns. In detail, 0.8% of the German general population fulfilled the BDD criteria and reported repetitive acts of at least one hour/day. The revised criteria of BDD in DSM-5 do not seem to have an impact on prevalence rates. However, the recently added B-criterion reflects more precisely the clinical symptoms of BDD, and may be useful for distinguishing between various severity levels related to repetitive behaviors/mental acts. Copyright © 2015 Elsevier Inc. All rights reserved.

Cued Panic Attacks in Body Dysmorphic Disorder

PubMed Central

Phillips, Katharine A.; Menard, William; Bjornsson, Andri S.

2013-01-01

Background Body dysmorphic disorder (BDD) is a common and often severe disorder. Clinical observations suggest that panic attacks triggered by BDD symptoms may be common. However, to our knowledge, no study has examined such panic attacks in BDD. We investigated the prevalence, clinical features, and correlates of BDD-triggered panic attacks in individuals with this disorder. Methods Panic attacks and other variables were assessed using reliable and valid measures in 76 individuals with lifetime DSM-IV BDD. Results 28.9% (95% CI, 18.5%–39.4%) of participants reported lifetime panic attacks triggered by BDD symptoms. The most common triggers of such attacks were feeling that others were looking at or scrutinizing the perceived appearance defects (61.9%), looking in the mirror at perceived defects (38.1%), and being in bright light where perceived defects would be more visible (23.8%). The most common panic attack symptoms were palpitations (86.4%), sweating (66.7%), shortness of breath (63.6%), trembling or shaking (63.6%), and fear of losing control or going crazy (63.6%). Compared to participants without such panic attacks, those with BDD-triggered panic attacks had more severe lifetime BDD, social anxiety, and depressive symptoms, as well as poorer functioning and quality of life on a number of measures. They were also less likely to be employed and more likely to have been psychiatrically hospitalized and to have had suicidal ideation due to BDD. Conclusions Panic attacks triggered by BDD-related situations appear common in individuals with this disorder. BDD-triggered panic attacks were associated with greater symptom severity and morbidity. PMID:23653076

Combination process of diamond machining and roll-to-roll UV-replication for thin film micro- and nanostructures

NASA Astrophysics Data System (ADS)

Väyrynen, J.; Mönkkönen, K.; Siitonen, S.

2016-09-01

Roll-to-roll (R2R) ultraviolet (UV) curable embossing replication process is a highly accurate and cost effective way to replicate large quantities of thin film polymer parts. These structures can be used for microfluidics, LED-optics, light guides, displays, cameras, diffusers, decorative, laser sensing and measuring devices. In the R2R UV-process, plastic thin film coated with UV-curable lacquer, passes through an imprinting embossing drum and is then hardened by an UV-lamp. One key element for mastering this process is the ability to manufacture a rotating drum containing micro- and nanostructures. Depending on the pattern shapes, the drum can be directly machined by diamond machining or it can be done through wafer level lithographical process. Due to the shrinkage of UV-curable lacquer, the R2R drum pattern process needs to be prototyped few times, in order to get the desired performance and shape from the R2R produced part. To speed up the prototyping and overall process we have developed a combination process where planar diamond machining patterns are being turned into a drum roller. Initially diamond machined patterns from a planar surface are replicated on a polymer sheet using UV-replication. Secondly, a nickel stamper shim is grown form the polymer sheet and at the end the stamper is turned into a roller and used in the R2R process. This process allows various micro milled, turned, grooved and ruled structures to be made at thin film products through the R2R process. In this paper, the process flow and examples of fabricating R2R embossed UVcurable thin film micro- and nanostructures from planar diamond machined patterns, is reported.

Characterization of diamond thin films and related materials

NASA Astrophysics Data System (ADS)

McKindra, Travis Kyle

Thin carbon films including sputtered deposited graphite and CO 2 laser-assisted combustion-flame deposited graphite and diamond thin films were characterized using optical and electron microscopy, X-ray diffraction and micro-Raman spectroscopy. Amorphous carbon thin films were deposited by DC magnetron sputtering using Ar/O2 gases. The film morphology changed with the oxygen content. The deposition rate decreased as the amount of oxygen increased due to oxygen reacting with the growing film. The use of oxygen in the working gas enhanced the crystalline nature of the films. Graphite was deposited on WC substrates by a CO2 laser-assisted O2/C2H2 combustion-flame method. Two distinct microstructural areas were observed; an inner core of dense material surrounded by an outer shell of lamellar-like material. The deposits were crystalline regardless of the laser power and deposition times of a few minutes. Diamond films were deposited by a CO2 laser-assisted O 2/C2H2/C2H4 combustion-flame method with the laser focused parallel to the substrate surface. The laser enhanced diamond growth was most pronounced when deposited with a 10.532 microm CO2 laser wavelength tuned to the CH2-wagging vibrational mode of the C2H4 molecule. Nucleation of diamond thin films deposited with and without using a CO 2 laser-assisted combustion-flame process was investigated. With no laser there was nucleation of a sub-layer of grains followed by irregular grain growth. An untuned laser wavelength yielded nucleation of a sub-layer then columnar grain growth. The 10.532 microm tuned laser wavelength caused growth of columnar grains.

Influence of non-adherent yeast cells on electrical characteristics of diamond-based field-effect transistors

NASA Astrophysics Data System (ADS)

Procházka, Václav; Cifra, Michal; Kulha, Pavel; Ižák, Tibor; Rezek, Bohuslav; Kromka, Alexander

2017-02-01

Diamond thin films provide unique features as substrates for cell cultures and as bio-electronic sensors. Here we employ solution-gated field effect transistors (SGFET) based on nanocrystalline diamond thin films with H-terminated surface which exhibits the sub-surface p-type conductive channel. We study an influence of yeast cells (Saccharomyces cerevisiae) on electrical characteristics of the diamond SGFETs. Two different cell culture solutions (sucrose and yeast peptone dextrose-YPD) are used, with and without the cells. We have found that transfer characteristics of the SGFETs exhibit a negative shift of the gate voltage by -26 mV and -42 mV for sucrose and YPD with cells in comparison to blank solutions without the cells. This effect is attributed to a local pH change in close vicinity of the H-terminated diamond surface due to metabolic processes of the yeast cells. The pH sensitivity of the diamond-based SGFETs, the role of cell and protein adhesion on the gate surface and the role of negative surface charge of yeast cells on the SGFETs electrical characteristics are discussed as well.

The Presentation of Body Dysmorphic Disorder in Medical Settings

PubMed Central

Phillips, Katharine A.

2006-01-01

Body dysmorphic disorder (BDD) is a relatively common psychiatric illness that often presents to mental health professionals as well as nonpsychiatric physicians. However, BDD usually goes unrecognized and undiagnosed in clinical settings. It is important to recognize and accurately diagnose BDD because this often secret illness may be debilitating. Patients with BDD typically have markedly impaired functioning, notably poor quality of life, and a high rate of suicidal ideation and suicide attempts. Thus, it is important to screen patients for BDD and avoid misdiagnosing it as another illness. Nonpsychiatric treatments (eg, dermatologic, surgical), which most patients seek and receive, appear ineffective for BDD and can be risky for physicians to provide. This article provides a clinically focused overview of BDD, including its symptoms, morbidity, case examples, nonpsychiatric (ie, cosmetic) treatment, diagnostic “do’s” and “don’ts,” and suggestions for how to persuade patients to accept appropriate psychiatric care. PMID:17183412

Suicidality in Body Dysmorphic Disorder

PubMed Central

Phillips, Katharine A.

2008-01-01

Suicidal ideation, suicide attempts, and completed suicide appear common in individuals with body dysmorphic disorder (BDD). Available evidence indicates that approximately 80% of individuals with BDD experience lifetime suicidal ideation and 24% to 28% have attempted suicide. Although data on completed suicide are limited and preliminary, the suicide rate appears markedly high. These findings underscore the importance of recognizing and effectively treating BDD. However, BDD is underrecognized in clinical settings even though it is relatively common and often presents to psychiatrists and other mental health practitioners, dermatologists, surgeons, and other physicians. This article reviews available evidence on suicidality in BDD and discusses how to recognize and diagnose this often secret disorder. Efficacious treatments for BDD, ie, serotonin reuptake inhibitors (SRIs) and cognitive-behavioral therapy, are also discussed. Although data are limited, it appears that SRIs often diminish suicidality in these patients. Additional research is greatly needed on suicidality rates, characteristics, correlates, risk factors, treatment, and prevention of suicidality in BDD. PMID:18449358

Anodic stripping voltammetry of gold nanoparticles at boron-doped diamond electrodes and its application in immunochromatographic strip tests.

PubMed

Ivandini, Tribidasari A; Wicaksono, Wiyogo P; Saepudin, Endang; Rismetov, Bakhadir; Einaga, Yasuaki

2015-03-01

Anodic stripping voltammetry (ASV) of colloidal gold-nanoparticles (AuNPs) was investigated at boron-doped diamond (BDD) electrodes in 50 mM HClO4. A deposition time of 300 s at-0.2 V (vs. Ag/AgCl) was fixed as the condition for the ASV. The voltammograms showed oxidation peaks that could be attributed to the oxidation of gold. These oxidation peaks were then investigated for potential application in immunochromatographic strip tests for the selective and quantitative detection of melamine, in which AuNPs were used as the label for the antibody of melamine. Linear regression of the oxidation peak currents appeared in the concentration range from 0.05-0.6 μg/mL melamine standard, with an estimated LOD of 0.069 μg/mL and an average relative standard deviation of 8.0%. This indicated that the method could be considered as an alternative method for selective and quantitative immunochromatographic applications. The validity was examined by the measurements of melamine injected into milk samples, which showed good recovery percentages during the measurements. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of a biochemical oxygen demand sensor using gold-modified boron doped diamond electrodes.

PubMed

Ivandini, Tribidasari A; Saepudin, Endang; Wardah, Habibah; Harmesa; Dewangga, Netra; Einaga, Yasuaki

2012-11-20

Gold-modified boron doped diamond (BDD) electrodes were examined for the amperometric detection of oxygen as well as a detector for measuring biochemical oxygen demand (BOD) using Rhodotorula mucilaginosa UICC Y-181. An optimum potential of -0.5 V (vs Ag/AgCl) was applied, and the optimum waiting time was observed to be 20 min. A linear calibration curve for oxygen reduction was achieved with a sensitivity of 1.4 μA mg(-1) L oxygen. Furthermore, a linear calibration curve in the glucose concentration range of 0.1-0.5 mM (equivalent to 10-50 mg L(-1) BOD) was obtained with an estimated detection limit of 4 mg L(-1) BOD. Excellent reproducibility of the BOD sensor was shown with an RSD of 0.9%. Moreover, the BOD sensor showed good tolerance against the presence of copper ions up to a maximum concentration of 0.80 μM (equivalent to 50 ppb). The sensor was applied to BOD measurements of the water from a lake at the University of Indonesia in Jakarta, Indonesia, with results comparable to those made using a standard method for BOD measurement.

Propham mineralization in aqueous medium by anodic oxidation using boron-doped diamond anode: influence of experimental parameters on degradation kinetics and mineralization efficiency.

PubMed

Ozcan, Ali; Sahin, Yücel; Koparal, A Savaş; Oturan, Mehmet A

2008-06-01

This study aims the removal of a carbamate herbicide, propham, from aqueous solution by direct electrochemical advanced oxidation process using a boron-doped diamond (BDD) anode. This electrode produces large quantities of hydroxyl radicals from oxidation of water, which leads to the oxidative degradation of propham up to its total mineralization. Effect of operational parameters such as current, temperature, pH and supporting electrolyte on the degradation and mineralization rate was studied. The applied current and temperature exert a prominent effect on the total organic carbon (TOC) removal rate of the solutions. The mineralization of propham can be performed at any pH value between 3 and 11 without any loss in oxidation efficiency. The propham decay and its overall mineralization reaction follows a pseudo-first-order kinetics. The apparent rate constant value of propham oxidation was determined as 4.8 x 10(-4)s(-1) at 100 mA and 35 degrees C in the presence of 50mM Na(2)SO(4) in acidic media (pH: 3). A general mineralization sequence was proposed considering the identified oxidation intermediates.

Molecular Signature of Pseudomonas aeruginosa with Simultaneous Nanomolar Detection of Quorum Sensing Signaling Molecules at a Boron-Doped Diamond Electrode

NASA Astrophysics Data System (ADS)

Buzid, Alyah; Shang, Fengjun; Reen, F. Jerry; Muimhneacháin, Eoin Ó.; Clarke, Sarah L.; Zhou, Lin; Luong, John H. T.; O'Gara, Fergal; McGlacken, Gerard P.; Glennon, Jeremy D.

2016-07-01

Electroanalysis was performed using a boron-doped diamond (BDD) electrode for the simultaneous detection of 2-heptyl-3-hydroxy-4-quinolone (PQS), 2-heptyl-4-hydroxyquinoline (HHQ) and pyocyanin (PYO). PQS and its precursor HHQ are two important signal molecules produced by Pseudomonas aeruginosa, while PYO is a redox active toxin involved in virulence and pathogenesis. This Gram-negative and opportunistic human pathogen is associated with a hospital-acquired infection particularly in patients with compromised immunity and is the primary cause of morbidity and mortality in cystic fibrosis (CF) patients. Early detection is crucial in the clinical management of this pathogen, with established infections entering a biofilm lifestyle that is refractory to conventional antibiotic therapies. Herein, a detection procedure was optimized and proven for the simultaneous detection of PYO, HHQ and PQS in standard mixtures, biological samples, and P. aeruginosa spiked CF sputum samples with remarkable sensitivity, down to nanomolar levels. Differential pulse voltammetry (DPV) scans were also applicable for monitoring the production of PYO, HHQ and PQS in P. aeruginosa PA14 over 8 h of cultivation. The simultaneous detection of these three compounds represents a molecular signature specific to this pathogen.

Pulse-resolved intensity measurements at a hard X-ray FEL using semi-transparent diamond detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roth, Thomas; Freund, Wolfgang; Boesenberg, Ulrike

Solid-state ionization chambers are presented based on thin diamond crystals that allow pulse-resolved intensity measurements at a hard X-ray free-electron laser (FEL), up to the 4.5 MHz repetition rate that will become available at the European XFEL. Due to the small X-ray absorption of diamond the thin detectors are semi-transparent which eases their use as non-invasive monitoring devices in the beam. FELs are characterized by strong pulse-to-pulse intensity fluctuations due to the self-amplified spontaneous emission (SASE) process and in many experiments it is mandatory to monitor the intensity of each individual pulse. Two diamond detectors with different electrode materials, berylliummore » and graphite, were tested as intensity monitors at the XCS endstation of the Linac Coherent Light Source (LCLS) using the pink SASE beam at 9 keV. The performance is compared with LCLS standard monitors that detect X-rays backscattered from thin SiN foils placed in the beam. In conclusion, the graphite detector can also be used as a beam position monitor although with rather coarse resolution.« less

Micro-architecture embedding ultra-thin interlayer to bond diamond and silicon via direct fusion

NASA Astrophysics Data System (ADS)

Kim, Jong Cheol; Kim, Jongsik; Xin, Yan; Lee, Jinhyung; Kim, Young-Gyun; Subhash, Ghatu; Singh, Rajiv K.; Arjunan, Arul C.; Lee, Haigun

2018-05-01

The continuous demand on miniaturized electronic circuits bearing high power density illuminates the need to modify the silicon-on-insulator-based chip architecture. This is because of the low thermal conductivity of the few hundred nanometer-thick insulator present between the silicon substrate and active layers. The thick insulator is notorious for releasing the heat generated from the active layers during the operation of devices, leading to degradation in their performance and thus reducing their lifetime. To avoid the heat accumulation, we propose a method to fabricate the silicon-on-diamond (SOD) microstructure featured by an exceptionally thin silicon oxycarbide interlayer (˜3 nm). While exploiting the diamond as an insulator, we employ spark plasma sintering to render the silicon directly fused to the diamond. Notably, this process can manufacture the SOD microarchitecture via a simple/rapid way and incorporates the ultra-thin interlayer for minute thermal resistance. The method invented herein expects to minimize the thermal interfacial resistance of the devices and is thus deemed as a breakthrough appealing to the current chip industry.

Pulse-resolved intensity measurements at a hard X-ray FEL using semi-transparent diamond detectors

DOE PAGES

Roth, Thomas; Freund, Wolfgang; Boesenberg, Ulrike; ...

2018-01-01

Solid-state ionization chambers are presented based on thin diamond crystals that allow pulse-resolved intensity measurements at a hard X-ray free-electron laser (FEL), up to the 4.5 MHz repetition rate that will become available at the European XFEL. Due to the small X-ray absorption of diamond the thin detectors are semi-transparent which eases their use as non-invasive monitoring devices in the beam. FELs are characterized by strong pulse-to-pulse intensity fluctuations due to the self-amplified spontaneous emission (SASE) process and in many experiments it is mandatory to monitor the intensity of each individual pulse. Two diamond detectors with different electrode materials, berylliummore » and graphite, were tested as intensity monitors at the XCS endstation of the Linac Coherent Light Source (LCLS) using the pink SASE beam at 9 keV. The performance is compared with LCLS standard monitors that detect X-rays backscattered from thin SiN foils placed in the beam. In conclusion, the graphite detector can also be used as a beam position monitor although with rather coarse resolution.« less

Personality traits as vulnerability factors in body dysmorphic disorder.

PubMed

Schieber, Katharina; Kollei, Ines; de Zwaan, Martina; Müller, Astrid; Martin, Alexandra

2013-11-30

Cognitive behavioural models consider certain personality traits to be risk factors for the development of Body Dysmorphic Disorder (BDD). Research on personality traits in BDD is scarce, therefore this study examined perfectionism, aesthetic sensitivity and the behavioural inhibition system (BIS) in BDD. Furthermore, the association between these personality traits and the extent of dysmorphic concerns was investigated. Individuals with BDD (n=58) and a population based control sample (n=2071), selected from a representative German population survey, completed self-report questionnaires assessing DSM-5 criteria of BDD, dysmorphic concerns, perfectionism, aesthetic sensitivity and BIS-reactivity. Individuals with BDD reported significantly higher degrees of perfectionism as well as of BIS-reactivity compared to the population based control sample, whereas the groups did not differ significantly regarding aesthetic sensitivity. However, for the total sample, each of the personality traits was related dimensionally to dysmorphic concerns. Current BDD models consider perfectionism and aesthetic sensitivity to be vulnerability factors. In addition to these concepts, the present study suggests that BIS-reactivity is related to BDD. Self-reported aesthetic sensitivity was not found to be specifically pronounced in BDD, but along with perfectionism and BIS-reactivity aesthetic sensitivity was generally associated with dysmorphic concerns. © 2013 Elsevier Ireland Ltd. All rights reserved.

Set shifting and visuospatial organization deficits in body dysmorphic disorder.

PubMed

Greenberg, Jennifer L; Weingarden, Hilary; Reuman, Lillian; Abrams, Dylan; Mothi, Suraj S; Wilhelm, Sabine

2017-11-24

Individuals with body dysmorphic disorder (BDD) over-attend to perceived defect(s) in their physical appearance, often becoming "stuck" obsessing about perceived flaws and engaging in rituals to hide flaws. These symptoms suggest that individuals with BDD may experience deficits in underlying neurocognitive functions, such as set-shifting and visuospatial organization. These deficits have been implicated as risk and maintenance factors in disorders with similarities to BDD but have been minimally investigated in BDD. The present study examined differences in neurocognitive functions among BDD participants (n = 20) compared to healthy controls (HCs; n = 20). Participants completed neuropsychological assessments measuring set-shifting (Cambridge Neuropsychological Test Automated Battery Intra-Extra Dimensional Set Shift [IED] task) and visuospatial organization and memory (Rey-Osterrieth Complex Figure Test [ROCF]). Results revealed a set-shifting deficit among BDD participants compared to HCs on the IED. On the ROCF, BDD participants exhibited deficits in visuospatial organization compared to HCs, but they did not differ in visuospatial memory compared to HCs. Results did not change when accounting for depression severity. Findings highlight neurocognitive deficits as potential endophenotype markers of clinical features (i.e., delusionality). Understanding neuropsychological deficits may clarify similarities and differences between BDD and related disorders and may guide targets for BDD treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

A comparison study of body dysmorphic disorder versus social phobia

PubMed Central

Kelly, Megan M.; Dalrymple, Kristy; Zimmerman, Mark; Phillips, Katharine A.

2012-01-01

Body dysmorphic disorder (BDD) shares many characteristics with social phobia (SP), including high levels of social anxiety and avoidance, but to our knowledge no studies have directly compared these disorders’ demographic and clinical features. Demographic and clinical features were compared in individuals with BDD (n=172), SP (n=644), and comorbid BDD/SP (n=125). SP participants had a significantly earlier age of onset and lower educational attainment than BDD participants. BDD participants were significantly less likely to ever be married than SP participants, had a greater likelihood of ever being psychiatrically hospitalized, and had significantly lower mean GAF scores than SP participants. The two groups had different comorbidity patterns, which included a greater likelihood for BDD participants to have comorbid obsessive-compulsive disorder (OCD) or an eating disorder, versus a greater likelihood for SP participants to have a comorbid non-OCD anxiety disorder. The comorbid BDD/SP group had significantly greater morbidity across several domains than the SP only group, but not the BDD only group. In summary, although BDD and SP were similar across many demographic and clinical features, they had important differences. Future studies are needed to confirm these findings and address similarities and differences between these disorders across a broader range of variables. PMID:22999105

Seeing in the Mind's eye: Imagery rescripting for patients with body dysmorphic disorder. A single case series.

PubMed

Ritter, Viktoria; Stangier, Ulrich

2016-03-01

Intrusive images of appearance play an important role in the maintenance of body dysmorphic disorder (BDD) and are often linked to negative autobiographical experiences. However, to date there is no study examining the use and efficacy of imagery rescripting in BDD. This study investigated imagery rescripting in six patients with BDD, using a single case series A-B design. The intervention consisted of two treatment sessions (T1, T2). BDD and depressive symptoms were evaluated prior to (T1), post (T2) and two weeks after intervention (FU), using the Yale -Brown Obsessive Compulsive Scale for BDD (BDD-YBOCS), the Body Dysmorphic Symptoms Inventory, and the Beck Depression Inventory. At post-treatment, significant reductions in negative affect, distress, vividness and encapsulated beliefs associated with images and memories as well as an increased control were observed for five of six patients. These were maintained or decreased at two weeks follow-up. Scores on the BDD-YBOCS indicated a significant 26% improvement in BDD severity at follow-up for the whole group. Considering response as a ≥ 30% reduction in BDD-YBOCS score, four of six patients were classified as treatment responders. At follow-up, significant improvements in BDD and depressive symptoms were observed for the whole group. The small sample size and the lack of a control group limit the generalizability of our results. The findings indicate the potential efficacy of imagery rescripting, and highlight the need for further controlled trials. Imagery rescripting should be considered as a treatment technique within the cognitive framework of BDD. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Review of Body Dysmorphic Disorder in Aesthetic Surgery Patients and the Legal Implications.

PubMed

Sweis, Iliana E; Spitz, Jamie; Barry, David R; Cohen, Mimis

2017-08-01

Body dysmorphic disorder (BDD) is an often under-recognized yet severe psychiatric illness. There is limited guidance for plastic surgeons in the USA in how to recognize and manage patients with BDD and protect themselves from potential litigation and harm. Therefore, in collaboration with legal counsel, we remind our profession of the serious nature of patients with BDD, provide warning signs for recognizing BDD, and critically evaluate the validity of informed consent and the legal ramifications of operating on such patients in the USA. A literature review was performed to clearly define the psychopathology of BDD and identify cases of patients with BDD who underwent cosmetic surgery resulting in potential threats to the surgeon. An additional search of the legal literature was performed in collaboration with legal counsel to identify key cases of patients with BDD attempting litigation following cosmetic surgery procedures. The diagnostic criteria and psychopathology of BDD are presented. Warning signs are highlighted to alert the plastic surgeon to patients at high risk for BDD. Strategies for legal protection include a pre-procedure checklist for patients that are suspected of having a BDD diagnosis. Body dysmorphic disorder is prevalent in the cosmetic surgery population. Patients with BDD often have a poor outcome following aesthetic surgery, which can result in a dangerous or even deadly situation for the surgeon. We aim to remind aesthetic plastic surgeons of the psychopathology, severity, and specific risks associated with operating on patients with BDD while suggesting specific protective strategies. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Prevalence of Body Dysmorphic Disorder and its Association With Body Features in Female Medical Students.

PubMed

Shaffi Ahamed, Shaik; Enani, Jawaher; Alfaraidi, Lama; Sannari, Lujain; Algain, Rihaf; Alsawah, Zainah; Al Hazmi, Ali

2016-06-01

Body dysmorphic disorder (BDD) is a distressing psychiatric disorder. So far there have not been any studies on BDD in Saudi Arabia. The aim of this study was to determine the prevalence of body dysmorphic disorder in female medical students and to investigate whether there is an association between BDD and body features of concern, social anxiety and symptoms of BDD. A cross sectional study was carried out on female medical students of the college of medicine, King Saud University, Riyadh, Saudi Arabia during January to April, 2015. Data were collected using the body image disturbance questionnaire, Body dysmorphic disorder symptomatology and social interaction anxiety scale. Descriptive statistics, bivariate and multivariate analysis were used to analyze the results. Out of 365 students who filled out the questionnaire, 4.4% (95% confidence intervals (CI): 2.54% to 7.04%) were positive for BDD with skin (75%) and fat (68.8%) as the most frequent body features of concern. Ten features (skin, fat, chest, hips, buttocks, arms, legs, lips, fingers, and shoulders) out of twenty-six were significantly associated with BDD. Arms and chest were independently associated with BDD. The odds of presence of body concern related to "arms" was 4.3 (95% C.I: 1.5, 12.1) times more in BDD subjects than non-BDD subjects, while concern about "chest" was 3.8 (1.3, 10.9) times more when compared to non-BDD subjects. No statistically significant association was observed between BDD and social anxiety (P = 0.13). This was the first study conducted in Kingdom of Saudi Arabia (KSA) on female medical students, which quantified the prevalence of BDD and identified the body features associated with it. Body dysmorphic disorder is prevalent in female medical students but it is relatively rare and an unnoticed disorder.

Prevalence of Body Dysmorphic Disorder and its Association With Body Features in Female Medical Students

PubMed Central

Shaffi Ahamed, Shaik; Enani, Jawaher; Alfaraidi, Lama; Sannari, Lujain; Algain, Rihaf; Alsawah, Zainah; Al Hazmi, Ali

2016-01-01

Background Body dysmorphic disorder (BDD) is a distressing psychiatric disorder. So far there have not been any studies on BDD in Saudi Arabia. Objectives The aim of this study was to determine the prevalence of body dysmorphic disorder in female medical students and to investigate whether there is an association between BDD and body features of concern, social anxiety and symptoms of BDD. Materials and Methods A cross sectional study was carried out on female medical students of the college of medicine, King Saud University, Riyadh, Saudi Arabia during January to April, 2015. Data were collected using the body image disturbance questionnaire, Body dysmorphic disorder symptomatology and social interaction anxiety scale. Descriptive statistics, bivariate and multivariate analysis were used to analyze the results. Results Out of 365 students who filled out the questionnaire, 4.4% (95% confidence intervals (CI): 2.54% to 7.04%) were positive for BDD with skin (75%) and fat (68.8%) as the most frequent body features of concern. Ten features (skin, fat, chest, hips, buttocks, arms, legs, lips, fingers, and shoulders) out of twenty-six were significantly associated with BDD. Arms and chest were independently associated with BDD. The odds of presence of body concern related to “arms” was 4.3 (95% C.I: 1.5, 12.1) times more in BDD subjects than non-BDD subjects, while concern about “chest” was 3.8 (1.3, 10.9) times more when compared to non-BDD subjects. No statistically significant association was observed between BDD and social anxiety (P = 0.13). Conclusions This was the first study conducted in Kingdom of Saudi Arabia (KSA) on female medical students, which quantified the prevalence of BDD and identified the body features associated with it. Body dysmorphic disorder is prevalent in female medical students but it is relatively rare and an unnoticed disorder. PMID:27803720

Effect Of Chromium Underlayer On The Properties Of Nano-Crystalline Diamond Films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garratt, Elias; AlFaify, Salem; Yoshitake, T.

2013-01-11

This paper investigated the effect of chromium underlayer on the structure, microstructure and composition of the nano-crystalline diamond films. Nano-crystalline diamond thin films were deposited at high temperature in microwave-induced plasma diluted with nitrogen, on silicon substrate with a thin film of chromium as an underlayer. The composition, structure and microstructure of the deposited layers were analyzed using non-Rutherford Backscattering Spectrometry, Raman Spectroscopy, Near-Edge X-Ray Absorption Fine Structure, X-ray Diffraction and Atomic Force Microscopy. Nanoindentation studies showed that the films deposited on chromium underlayer have higher hardness values compared to those deposited on silicon without an underlayer. Diamond and graphiticmore » phases of the films evaluated by x-ray and optical spectroscopic analysis determined consistency between sp2 and sp3 phases of carbon in chromium sample to that of diamond grown on silicon. Diffusion of chromium was observed using ion beam analysis which was correlated with the formation of chromium complexes by x-ray diffraction.« less

Effect of chromium underlayer on the properties of nano-crystalline diamond films

NASA Astrophysics Data System (ADS)

Garratt, E.; AlFaify, S.; Yoshitake, T.; Katamune, Y.; Bowden, M.; Nandasiri, M.; Ghantasala, M.; Mancini, D. C.; Thevuthasan, S.; Kayani, A.

2013-01-01

This paper investigated the effect of chromium underlayer on the structure, microstructure, and composition of the nano-crystalline diamond films. Nano-crystalline diamond thin films were deposited at high temperature in microwave-induced plasma diluted with nitrogen, on single crystal silicon substrate with a thin film of chromium as an underlayer. Characterization of the film was implemented using non-Rutherford backscattering spectrometry, Raman spectroscopy, near-edge x-ray absorption fine structure, x-ray diffraction, and atomic force microscopy. Nanoindentation studies showed that the films deposited on chromium underlayer have higher hardness values compared to those deposited on silicon without an underlayer. Diamond and graphitic phases of the films evaluated by x-ray and optical spectroscopic analyses determined consistency between the sp2 and sp3 phases of carbon in chromium sample to that of diamond grown on silicon. Diffusion of chromium was observed using ion beam analysis which was correlated with the formation of chromium complexes by x-ray diffraction.

Ultra-thin nanocrystalline diamond membranes as pressure sensors for harsh environments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Janssens, S. D., E-mail: stoffel.d.janssens@gmail.com; Haenen, K., E-mail: ken.haenen@uhasselt.be; IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek

2014-02-17

Glass and diamond are suitable materials for harsh environments. Here, a procedure for fabricating ultra-thin nanocrystalline diamond membranes on glass, acting as an electrically insulating substrate, is presented. In order to investigate the pressure sensing properties of such membranes, a circular, highly conductive boron-doped nanocrystalline diamond membrane with a resistivity of 38 mΩ cm, a thickness of 150 nm, and a diameter of 555 μm is fabricated in the middle of a Hall bar structure. During the application of a positive differential pressure under the membrane (0–0.7 bar), four point piezoresistive effect measurements are performed. From these measurements, it can be concluded that the resistancemore » response of the membrane, as a function of differential pressure, is highly linear and sensitive.« less

Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang Jie; Fundamental Department, Aviation University, Changchun 130022; Li Ming

2011-04-15

In this paper, a W-Ta thin-film thermocouple has been integrated on a diamond anvil cell by thin-film deposition and photolithography methods. The thermocouple was calibrated and its thermal electromotive force was studied under high pressure. The results indicate that the thermal electromotive force of the thermocouple exhibits a linear relationship with temperature and is not associated with pressure. The resistivity measurement of ZnS powders under high pressure at different temperatures shows that the phase transition pressure decreases as the temperature increases.

Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure.

PubMed

Yang, Jie; Li, Ming; Zhang, Honglin; Gao, Chunxiao

2011-04-01

In this paper, a W-Ta thin-film thermocouple has been integrated on a diamond anvil cell by thin-film deposition and photolithography methods. The thermocouple was calibrated and its thermal electromotive force was studied under high pressure. The results indicate that the thermal electromotive force of the thermocouple exhibits a linear relationship with temperature and is not associated with pressure. The resistivity measurement of ZnS powders under high pressure at different temperatures shows that the phase transition pressure decreases as the temperature increases. © 2011 American Institute of Physics

Body dysmorphic disorder: some key issues for DSM-V.

PubMed

Phillips, Katharine A; Wilhelm, Sabine; Koran, Lorrin M; Didie, Elizabeth R; Fallon, Brian A; Feusner, Jamie; Stein, Dan J

2010-06-01

Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with an imagined or slight defect in appearance, has been described for more than a century and increasingly studied over the past several decades. This article provides a focused review of issues pertaining to BDD that are relevant to DSM-V. The review presents a number of options and preliminary recommendations to be considered for DSM-V: (1) Criterion A may benefit from some rewording, without changing its focus or meaning; (2) There are both advantages and disadvantages to adding a new criterion to reflect compulsive BDD behaviors; this possible addition requires further consideration; (3) A clinical significance criterion seems necessary for BDD to differentiate it from normal appearance concerns; (4) BDD and eating disorders have some overlapping features and need to be differentiated; some minor changes to DSM-IV's criterion C are suggested; (5) BDD should not be broadened to include body integrity identity disorder (apotemnophilia) or olfactory reference syndrome; (6) There is no compelling evidence for including diagnostic features or subtypes that are specific to gender-related, age-related, or cultural manifestations of BDD; (7) Adding muscle dysmorphia as a specifier may have clinical utility; and (8) The ICD-10 criteria for hypochondriacal disorder are not suitable for BDD, and there is no empirical evidence that BDD and hypochondriasis are the same disorder. The issue of how BDD's delusional variant should be classified in DSM-V is briefly discussed and will be addressed more extensively in a separate article. (c) 2010 Wiley-Liss, Inc.

Patient-identified events implicated in the development of body dysmorphic disorder.

PubMed

Weingarden, Hilary; Curley, Erin E; Renshaw, Keith D; Wilhelm, Sabine

2017-06-01

Little is known about the causes of body dysmorphic disorder (BDD), but researchers have proposed a diathesis-stress model. This study uses a patient-centered approach to identify stressful events to which patients attribute the development of their BDD symptoms. An Internet-recruited sample of 165 adults with BDD participated. A large minority of participants attributed the development of their BDD to a triggering event. Bullying experiences were the most commonly described type of event. Additionally, most events were interpersonal and occurred during grade school or middle school. There were no differences in severity of psychosocial outcomes between participants who did or did not attribute their BDD to a specific triggering event. However, participants who specifically attributed their BDD development to a bullying experience had poorer psychosocial outcomes (i.e., perceived social support, depression severity, functional impairment, quality of life) compared to those who attributed their BDD development to another type of triggering event. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cognitive-Behavioral Therapy for Youth with Body Dysmorphic Disorder: Current Status and Future Directions

PubMed Central

Phillips, Katharine A.; Rogers, Jamison

2011-01-01

SYNOPSIS Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with nonexistent or slight defect(s) in appearance, usually begins during early adolescence and appears to be common in youth. BDD is characterized by substantial impairment in psychosocial functioning and markedly high rates of suicidality. Cognitive-behavioral therapy (CBT) tailored to BDD’s unique features is the best tested and most promising psychosocial treatment for adults with BDD. CBT has been used for youth with BDD, but it has not been systematically developed for or tested in this age group, and there is a pressing need for this work to be done. This article focuses on CBT for BDD in adults and youth, possible adaptations for youth, and the need for treatment research in youth. We also discuss BDD’s prevalence, clinical features, how to diagnose BDD in youth, recommended pharmacotherapy for BDD (serotonin-reuptake inhibitors), and treatments that are not recommended (surgery and other cosmetic treatments). PMID:21440856

Mechanical design of thin-film diamond crystal mounting apparatus for coherence preservation hard x-ray optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shu, Deming, E-mail: shu@aps.anl.gov; Shvyd’ko, Yuri V.; Stoupin, Stanislav

2016-07-27

A new thin-film diamond crystal mounting apparatus has been designed at the Advanced Photon Source (APS) for coherence preservation hard x-ray optics with optimized thermal contact and minimized crystal strain. This novel mechanical design can be applied to new development in the field of: x-ray optics cavities for hard x-ray free-electron laser oscillators (XFELOs), self-seeding monochromators for hard x-ray free-electron laser (XFEL) with high average thermal loading, high heat load diamond crystal monochromators and beam-sharing/beam-split-and-delay devices for XFEL facilities and future upgraded high-brightness coherent x-ray source in the MBA lattice configuration at the APS.

The low coherence Fabry-Pérot interferometer with diamond and ZnO layers

NASA Astrophysics Data System (ADS)

Majchrowicz, D.; Den, W.; Hirsch, M.

2016-09-01

The authors present a fiber-optic Fabry-Pérot interferometer built with the application of diamond and zinc oxide (ZnO) thin layers. Thin ZnO films were deposited on the tip of a standard telecommunication single-mode optical fiber (SMF- 28) while the diamond layer was grown on the plate of silicon substrate. Investigated ZnO layers were fabricated by atomic layer deposition (ALD) and the diamond films were deposited using Microwave Plasma Enhanced Chemical Vapor Deposition (μPE CVD) system. Different thickness of layers was examined. The measurements were performed for the fiber-optic Fabry-Pérot interferometer working in the reflective mode. Spectra were registered for various thicknesses of ZnO layer and various length of the air cavity. As a light source, two superluminescent diodes (SLD) with central wavelength of 1300 nm and 1550 nm were used in measurement set-up.

The Power Within: The Experimental Manipulation of Power Interacts with Trait BDD Symptoms to Predict Interoceptive Accuracy

PubMed Central

Kunstman, Jonathan W.; Clerkin, Elise M.; Palmer, Kateyln; Peters, M. Taylar; Dodd, Dorian R.; Smith, April R.

2015-01-01

Background and Objectives This study tested whether relatively low levels of interoceptive accuracy (IAcc) are associated with body dysmorphic disorder (BDD) symptoms. Additionally, given research indicating that power attunes individuals to their internal states, we sought to determine if state interoceptive accuracy could be improved through an experimental manipulation of power. Method Undergraduate women (N = 101) completed a baseline measure of interoceptive accuracy and then were randomized to a power or control condition. Participants were primed with power or a neutral control topic and then completed a post-manipulation measure of state IAcc. Trait BDD symptoms were assessed with a self-report measure. Results Controlling for baseline IAcc, within the control condition, there was a significant inverse relationship between trait BDD symptoms and interoceptive accuracy. Continuing to control for baseline IAcc, within the power condition, there was not a significant relationship between trait BDD symptoms and IAcc, suggesting that power may have attenuated this relationship. At high levels of BDD symptomology, there was also a significant simple effect of experimental condition, such that participants in the power (vs. control) condition had better interoceptive accuracy. These results provide initial evidence that power may positively impact interoceptive accuracy among those with high levels of BDD symptoms. Limitations This cross-sectional study utilized a demographically homogenous sample of women that reflected a broad range of symptoms; thus, although there were a number of participants reporting elevated BDD symptoms, these findings might not generalize to other populations or clinical samples. Conclusions . This study provides the first direct test of the relationship between trait BDD symptoms and IAcc, and provides preliminary evidence that among those with severe BDD symptoms, power may help connect individuals with their internal states. Future research testing the mechanisms linking BDD symptoms with IAcc, as well as how individuals can better connect with their internal experiences is needed. PMID:26295932

The power within: The experimental manipulation of power interacts with trait BDD symptoms to predict interoceptive accuracy.

PubMed

Kunstman, Jonathan W; Clerkin, Elise M; Palmer, Kateyln; Peters, M Taylar; Dodd, Dorian R; Smith, April R

2016-03-01

This study tested whether relatively low levels of interoceptive accuracy (IAcc) are associated with body dysmorphic disorder (BDD) symptoms. Additionally, given research indicating that power attunes individuals to their internal states, we sought to determine if state interoceptive accuracy could be improved through an experimental manipulation of power.. Undergraduate women (N = 101) completed a baseline measure of interoceptive accuracy and then were randomized to a power or control condition. Participants were primed with power or a neutral control topic and then completed a post-manipulation measure of state IAcc. Trait BDD symptoms were assessed with a self-report measure. Controlling for baseline IAcc, within the control condition, there was a significant inverse relationship between trait BDD symptoms and interoceptive accuracy. Continuing to control for baseline IAcc, within the power condition, there was not a significant relationship between trait BDD symptoms and IAcc, suggesting that power may have attenuated this relationship. At high levels of BDD symptomology, there was also a significant simple effect of experimental condition, such that participants in the power (vs. control) condition had better interoceptive accuracy. These results provide initial evidence that power may positively impact interoceptive accuracy among those with high levels of BDD symptoms.. This cross-sectional study utilized a demographically homogenous sample of women that reflected a broad range of symptoms; thus, although there were a number of participants reporting elevated BDD symptoms, these findings might not generalize to other populations or clinical samples. This study provides the first direct test of the relationship between trait BDD symptoms and IAcc, and provides preliminary evidence that among those with severe BDD symptoms, power may help connect individuals with their internal states. Future research testing the mechanisms linking BDD symptoms with IAcc, as well as how individuals can better connect with their internal experiences is needed.. Copyright © 2015 Elsevier Ltd. All rights reserved.

AC calorimetry of H2O at pressures up to 9 GPa in diamond anvil cells

NASA Astrophysics Data System (ADS)

Geballe, Zachary M.; Struzhkin, Viktor V.

2017-06-01

If successfully developed, calorimetry at tens of GPa of pressure could help characterize phase transitions in materials such as high-pressure minerals, metals, and molecular solids. Here, we extend alternating-current calorimetry to 9 GPa and 300 K in a diamond anvil cell and use it to study phase transitions in H2O. In particular, water is loaded into the sample chambers of diamond-cells, along with thin metal heaters (1 μm-thick platinum or 20 nm-thick gold on a glass substrate) that drive high-frequency temperature oscillations (20 Hz to 600 kHz; 1 to 10 K). The heaters also act as thermometers via the third-harmonic technique, yielding calorimetric data on (1) heat conduction to the diamonds and (2) heat transport into substrate and sample. Using this method during temperature cycles from 300 to 200 K, we document melting, freezing, and proton ordering and disordering transitions of H2O at 0 to 9 GPa, and characterize changes in thermal conductivity and heat capacity across these transitions. The technique and analysis pave the way for calorimetry experiments on any non-metal at pressures up to ˜100 GPa, provided a thin layer (several μm-thick) of thermal insulation supports a metallic thin-film (tens of nm thick) Joule-heater attached to low contact resistance leads inside the sample chamber of a diamond-cell.

Toward deep blue nano hope diamonds: heavily boron-doped diamond nanoparticles.

PubMed

Heyer, Steffen; Janssen, Wiebke; Turner, Stuart; Lu, Ying-Gang; Yeap, Weng Siang; Verbeeck, Jo; Haenen, Ken; Krueger, Anke

2014-06-24

The production of boron-doped diamond nanoparticles enables the application of this material for a broad range of fields, such as electrochemistry, thermal management, and fundamental superconductivity research. Here we present the production of highly boron-doped diamond nanoparticles using boron-doped CVD diamond films as a starting material. In a multistep milling process followed by purification and surface oxidation we obtained diamond nanoparticles of 10-60 nm with a boron content of approximately 2.3 × 10(21) cm(-3). Aberration-corrected HRTEM reveals the presence of defects within individual diamond grains, as well as a very thin nondiamond carbon layer at the particle surface. The boron K-edge electron energy-loss near-edge fine structure demonstrates that the B atoms are tetrahedrally embedded into the diamond lattice. The boron-doped diamond nanoparticles have been used to nucleate growth of a boron-doped diamond film by CVD that does not contain an insulating seeding layer.

Perceptual and cognitive biases in individuals with body dysmorphic disorder symptoms.

PubMed

Clerkin, Elise M; Teachman, Bethany A

2008-01-01

Given the extreme focus on perceived physical defects in body dysmorphic disorder (BDD), we expected that perceptual and cognitive biases related to physical appearance would be associated with BDD symptomology. To examine these hypotheses, participants ( N = 70) high and low in BDD symptoms completed tasks assessing visual perception and cognition. As expected, there were significant group differences in self-, but not other-, relevant cognitive biases. Perceptual bias results were mixed, with some evidence indicating that individuals high (versus low) in BDD symptoms literally see themselves in a less positive light. Further, individuals high in BDD symptoms failed to demonstrate a normative self-enhancement bias. Overall, this research points to the importance of assessing both cognitive and perceptual biases associated with BDD symptoms, and suggests that visual perception may be influenced by non-visual factors.

Perceptual and cognitive biases in individuals with body dysmorphic disorder symptoms

PubMed Central

Clerkin, Elise M.; Teachman, Bethany A.

2012-01-01

Given the extreme focus on perceived physical defects in body dysmorphic disorder (BDD), we expected that perceptual and cognitive biases related to physical appearance would be associated with BDD symptomology. To examine these hypotheses, participants (N = 70) high and low in BDD symptoms completed tasks assessing visual perception and cognition. As expected, there were significant group differences in self-, but not other-, relevant cognitive biases. Perceptual bias results were mixed, with some evidence indicating that individuals high (versus low) in BDD symptoms literally see themselves in a less positive light. Further, individuals high in BDD symptoms failed to demonstrate a normative self-enhancement bias. Overall, this research points to the importance of assessing both cognitive and perceptual biases associated with BDD symptoms, and suggests that visual perception may be influenced by non-visual factors. PMID:25125771

Patients with mild to moderate body dysmorphic disorder may benefit from rhinoplasty.

PubMed

Felix, Gabriel Almeida Arruda; de Brito, Maria José Azevedo; Nahas, Fabio Xerfan; Tavares, Hermano; Cordás, Táki Athanássios; Dini, Gal Moreira; Ferreira, Lydia Masako

2014-05-01

Body dysmorphic disorder (BDD) is one of the most common psychiatric conditions found in patients seeking cosmetic surgery. BDD is also a challenge for plastic surgeons because it is still an underdiagnosed mental disorder. The aims of this study were to prospectively investigate whether patients with mild to moderate BDD are suitable for rhinoplasty, and to assess BDD severity and patient satisfaction with the surgical outcome 1 year after the intervention. All women (n = 116) seeking rhinoplasty at a university hospital between September 2009 and August 2010 were recruited for the study and assessed for BDD. The final sample consisted of 31 patients aged 32 (standard deviation (SD), 10) years with mild to moderate BDD who underwent rhinoplasty. The participants were assessed preoperatively (baseline) and 1 year postoperatively with the Body Dysmorphic Disorder Examination (BDDE). Most patients (22/31, 71%) were of African descent. Socio-demographic variables and the extent of the nasal deformities had no effect on the severity of BDD symptoms and patient satisfaction with surgery outcome. At the 1-year postoperative follow-up, there was a significant decrease from baseline in BDDE scores and time spent by patients worrying about their appearance; 25 (25/31, 81%) patients experienced complete remission from BDD and 28 (28/31, 90%) were satisfied with the results of surgery. Rhinoplasty may be indicated in the treatment of female patients with mild to moderate BDD. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Degree connectivity in body dysmorphic disorder and relationships with obsessive and compulsive symptoms.

PubMed

Beucke, Jan C; Sepulcre, Jorge; Buhlmann, Ulrike; Kathmann, Norbert; Moody, Teena; Feusner, Jamie D

2016-10-01

Individuals with body dysmorphic disorder (BDD) and obsessive-compulsive disorder (OCD) are categorized within the same major diagnostic group and both show regional brain hyperactivity in the orbitofrontal cortex (OFC) and the basal ganglia during symptom provocation. While recent studies revealed that degree connectivity of these areas is abnormally high in OCD and positively correlates with symptom severity, no study has investigated degree connectivity in BDD. We used functional magnetic resonance imaging (fMRI) to compare the local and distant degree of functional connectivity in all brain areas between 28 unmedicated BDD participants and 28 demographically matched healthy controls during a face-processing task. Correlational analyses tested for associations between degree connectivity and symptom severity assessed by the BDD version of the Yale-Brown obsessive-compulsive scale (BDD-Y-BOCS). Reduced local amygdalar connectivity was found in participants with BDD. No differences in distant connectivity were found. BDD-Y-BOCS scores significantly correlated with the local connectivity of the posterior-lateral OFC, and distant connectivity of the posterior-lateral and post-central OFC, respectively. These findings represent preliminary evidence that individuals with BDD exhibit brain-behavioral associations related to obsessive thoughts and compulsive behaviors that are highly similar to correlations previously found in OCD, further underscoring their related pathophysiology. This relationship could be further elucidated through investigation of resting-state functional connectivity in BDD, ideally in direct comparison with OCD and other obsessive-compulsive and related disorders. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.

Electrical applications of CVD diamond films

NASA Astrophysics Data System (ADS)

Fujimori, Naoji

Electronics applications of CVD diamond films are reported. The properties of epitaxial diamond films are affected by the orientation of the substrate and the deposition conditions. Boron-doped epitaxial films are found to have the same characteristics as natural IIb diamonds. An LED and an FET were successfully fabricated using boron-doped epitaxial films and Schottky junctions. However, these devices did not exhibit satisfactory properties. Other applications of CVD diamond films include speaker diaphragms (as both a thin-film coating and a free-standing film), and as an ideal packaging material (due to its high thermal conductivity and low dielectric constant).

Electrochemical destruction of trans-cinnamic acid by advanced oxidation processes: kinetics, mineralization, and degradation route.

PubMed

Flores, Nelly; Thiam, Abdoulaye; Rodríguez, Rosa María; Centellas, Francesc; Cabot, Pere Lluís; Garrido, José Antonio; Brillas, Enric; Sirés, Ignasi

2017-03-01

Acidic solutions of trans-cinnamic acid at pH 3.0 have been comparatively treated by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF), and photoelectro-Fenton (PEF). The electrolytic experiments were carried out with a boron-doped diamond (BDD)/air-diffusion cell. The substrate was very slowly abated by AO-H 2 O 2 because of its low reaction rate with oxidizing • OH produced from water discharge at the BDD anode. In contrast, its removal was very rapid and at similar rate by EF and PEF due to the additional oxidation by • OH in the bulk, formed from Fenton's reaction between cathodically generated H 2 O 2 and added Fe 2+ . The AO-H 2 O 2 treatment yielded the lowest mineralization. The EF process led to persistent final products like Fe(III) complexes, which were quickly photolyzed upon UVA irradiation in PEF to give an almost total mineralization with 98 % total organic carbon removal. The effect of current density and substrate concentration on all the mineralization processes was examined. Gas chromatography-mass spectrometry (GC-MS) analysis of electrolyzed solutions allowed identifying five primary aromatics and one heteroaromatic molecule, whereas final carboxylic acids like fumaric, acetic, and oxalic were quantified by ion exclusion high-performance liquid chromatography (HPLC). From all the products detected, a degradation route for trans-cinnamic acid is proposed.

Electrochemical oxidation of COD from real textile wastewaters: Kinetic study and energy consumption.

PubMed

Zou, Jiaxiu; Peng, Xiaolan; Li, Miao; Xiong, Ying; Wang, Bing; Dong, Faqin; Wang, Bin

2017-03-01

In the present study, the electrochemical oxidation of real wastewaters discharged by textile industry was carried out using a boron-doped diamond (BDD) anode. The effect of operational variables, such as applied current density (20-100 mA·cm -2 ), NaCl concentration added to the real wastewaters (0-3 g·L -1 ), and pH value (2.0-10.0), on the kinetics of COD oxidation and on the energy consumption was carefully investigated. The obtained experimental results could be well matched with a proposed kinetic model, in which the indirect oxidation mediated by electrogenerated strong oxidants would be described through a pseudo-first-order kinetic constant k. Values of k exhibited a linear increase with increasing applied current density and decreasing pH value, and an exponential increase with NaCl concentration. Furthermore, high oxidation kinetics resulted in low specific energy consumption, but this conclusion was not suitable to the results obtained under different applied current density. Under the optimum operational conditions, it only took 3 h to complete remove the COD in the real textile wastewaters and the specific energy consumption could be as low as 11.12 kWh·kg -1  COD. The obtained results, low energy consumption and short electrolysis time, allowed to conclude that the electrochemical oxidation based on BDD anodes would have practical industrial application for the treatment of real textile wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electrochemical treatment of domestic wastewater using boron-doped diamond and nanostructured amorphous carbon electrodes.

PubMed

Daghrir, Rimeh; Drogui, Patrick; Tshibangu, Joel; Delegan, Nazar; El Khakani, My Ali

2014-05-01

The performance of the electrochemical oxidation process for efficient treatment of domestic wastewater loaded with organic matter was studied. The process was firstly evaluated in terms of its capability of producing an oxidant agent (H2O2) using amorphous carbon (or carbon felt) as cathode, whereas Ti/BDD electrode was used as anode. Relatively high concentrations of H2O2 (0.064 mM) was produced after 90 min of electrolysis time, at 4.0 A of current intensity and using amorphous carbon at the cathode. Factorial design and central composite design methodologies were successively used to define the optimal operating conditions to reach maximum removal of chemical oxygen demand (COD) and color. Current intensity and electrolysis time were found to influence the removal of COD and color. The contribution of current intensity on the removal of COD and color was around 59.1 and 58.8%, respectively, whereas the contribution of treatment time on the removal of COD and color was around 23.2 and 22.9%, respectively. The electrochemical treatment applied under 3.0 A of current intensity, during 120 min of electrolysis time and using Ti/BDD as anode, was found to be the optimal operating condition in terms of cost/effectiveness. Under these optimal conditions, the average removal rates of COD and color were 78.9 ± 2 and 85.5 ± 2 %, whereas 70% of total organic carbon removal was achieved.

Epithelial cell morphology and adhesion on diamond films deposited and chemically modified by plasma processes.

PubMed

Rezek, Bohuslav; Ukraintsev, Egor; Krátká, Marie; Taylor, Andrew; Fendrych, Frantisek; Mandys, Vaclav

2014-09-01

The authors show that nanocrystalline diamond (NCD) thin films prepared by microwave plasma enhanced chemical vapor deposition apparatus with a linear antenna delivery system are well compatible with epithelial cells (5637 human bladder carcinoma) and significantly improve the cell adhesion compared to reference glass substrates. This is attributed to better adhesion of adsorbed layers to diamond as observed by atomic force microscopy (AFM) beneath the cells. Moreover, the cell morphology can be adjusted by appropriate surface treatment of diamond by using hydrogen and oxygen plasma. Cell bodies, cytoplasmic rims, and filopodia were characterized by Peakforce AFM. Oxidized NCD films perform better than other substrates under all conditions (96% of cells adhered well). A thin adsorbed layer formed from culture medium and supplemented with fetal bovine serum (FBS) covered the diamond surface and played an important role in the cell adhesion. Nevertheless, 50-100 nm large aggregates formed from the RPMI medium without FBS facilitated cell adhesion also on hydrophobic hydrogenated NCD (increase from 23% to 61%). The authors discuss applicability for biomedical uses.

Synthesis and Characterization of Quenched and Crystalline Phases: Q-Carbon, Q-BN, Diamond and Phase-Pure c-BN

NASA Astrophysics Data System (ADS)

Bhaumik, Anagh; Narayan, Jagdish

2018-04-01

We report the synthesis and characterization of quenched (Q-carbon and Q-BN) and crystalline (diamond and c-BN) phases using a non-equilibrium technique. These phases are formed as a result of the melting and subsequent quenching of amorphous carbon and nanocrystalline h-BN in a super undercooled state by using high-power nanosecond laser pulses. Pulsed laser annealing also leads to the formation of nanoneedles, microneedles and single-crystal thin films of diamond and c-BN. This formation is dependent on the nucleation and growth times, which are controlled by laser energy density and thermal conductivities of substrate and as-deposited thin film. The diamond nuclei present in the Q-carbon structure ( 80% sp 3) can also be grown to larger sizes using the equilibrium hot filament chemical vapor deposition process. The texture of diamond and c-BN crystals is <111> under epitaxial growth and <110> under rapid unseeded crystallization. Our nanosecond laser processing opens up a roadmap to the fabrication of novel phases on heat-sensitive substrates.

Enhanced Photocatalytic Activity of Diamond Thin Films Using Embedded Ag Nanoparticles.

PubMed

Li, Shuo; Bandy, Jason A; Hamers, Robert J

2018-02-14

Silver nanoparticles embedded into the diamond thin films enhance the optical absorption and the photocatalytic activity toward the solvated electron-initiated reduction of N 2 to NH 3 in water. Here, we demonstrate the formation of diamond films with embedded Ag nanoparticles <100 nm in diameter. Cross-sectional scanning electron microscopy (SEM), energy-dependent SEM, and energy-dispersive X-ray analysis demonstrate the formation of encapsulated nanoparticles. Optical absorption measurements in the visible and ultraviolet region show that the resulting films exhibit plasmonic resonances in the visible and near-ultraviolet region. Measurements of photocatalytic activity using supraband gap (λ < 225 nm) and sub-band gap (λ > 225 nm) excitation show significantly enhanced ability to convert N 2 to NH 3 . Incorporation of Ag nanoparticles induces a nearly 5-fold increase in activity using a sub-band gap excitation with λ > 225 nm. Our results suggest that internal photoemission, in which electrons are excited from Ag into diamond's conduction band, is an important process that extends the wavelength region beyond diamond's band gap. Other factors, including Ag-induced optical scattering and formation of graphitic impurities are also discussed.

Design of a diamond-crystal monochromator for the LCLS hard x-ray self-seeding project

NASA Astrophysics Data System (ADS)

Shu, D.; Shvyd'ko, Y.; Amann, J.; Emma, P.; Stoupin, S.; Quintana, J.

2013-03-01

As the result of collaborations between the Advanced Photon Source (APS), Argonne National Laboratory, and the Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory, we have designed and constructed a diamond crystal monochromator for the LCLS hard x-ray self-seeding project. The novel monochromator is ultrahigh-vacuum compatible to meet the LCLS linear accelerator vacuum environmental requirement. A special graphite holder was designed for strain-free mount of the 110-μm thin synthetic diamond crystal plate provided by Technological Institute for Super-hard and Novel Carbon Materials of Russia (TISNCM). An in-vacuum multi-axis precision positioning mechanism is designed to manipulate the thin-film diamond holder with resolutions and stabilities required by the hard x-ray self-seeding physics. Optical encoders, limit switches, and hardware stops are established in the mechanism to ensure system reliability and to meet the accelerator personal and equipment safety interlock requirements. Molybdenum shields are installed in the monochromator to protect the encoders and associated electronics from radiation damage. Mechanical specifications, designs, and preliminary test results of the diamond monochromator are presented in this paper.

Clinical features of muscle dysmorphia among males with body dysmorphic disorder.

PubMed

Pope, Courtney G; Pope, Harrison G; Menard, William; Fay, Christina; Olivardia, Roberto; Phillips, Katharine A

2005-12-01

Muscle dysmorphia - a pathological preoccupation with muscularity - appears to be a form of body dysmorphic disorder (BDD) with a focus on muscularity. However, little is known about muscle dysmorphia in men with BDD, and no study has compared men with BDD who do and do not report muscle dysmorphia. To explore this issue, we reviewed the histories of 63 men with BDD; we compared those rated as having a history of muscle dysmorphia with those who had BDD but not muscle dysmorphia in several domains. The 14 men with muscle dysmorphia resembled the 49 comparison men in demographic features, BDD severity, delusionality, and number of non-muscle-related body parts of concern. However, those with muscle dysmorphia were more likely to have attempted suicide, had poorer quality of life, and had a higher frequency of any substance use disorder and anabolic steroid abuse. Thus, muscle dysmorphia was associated with greater psychopathology.

Clinical features of muscle dysmorphia among males with body dysmorphic disorder

PubMed Central

Pope, Courtney G.; Pope, Harrison G.; Menard, William; Fay, Christina; Olivardia, Roberto; Phillips, Katharine A.

2006-01-01

Muscle dysmorphia – a pathological preoccupation with muscularity – appears to be a form of body dysmorphic disorder (BDD) with a focus on muscularity. However, little is known about muscle dysmorphia in men with BDD, and no study has compared men with BDD who do and do not report muscle dysmorphia. To explore this issue, we reviewed the histories of 63 men with BDD; we compared those rated as having a history of muscle dysmorphia with those who had BDD but not muscle dysmorphia in several domains. The 14 men with muscle dysmorphia resembled the 49 comparison men in demographic features, BDD severity, delusionality, and number of non-muscle-related body parts of concern. However, those with muscle dysmorphia were more likely to have attempted suicide, had poorer quality of life, and had a higher frequency of any substance use disorder and anabolic steroid abuse. Thus, muscle dysmorphia was associated with greater psychopathology. PMID:17075613

Body dysmorphic symptoms: phenomenology and ethnicity.

PubMed

Marques, Luana; LeBlanc, Nicole; Weingarden, Hilary; Greenberg, Jennifer L; Traeger, Lara N; Keshaviah, Aparna; Wilhelm, Sabine

2011-03-01

Differences in the presentation of clinical features of body dysmorphic disorder (BDD) across ethnic groups have received little investigation. The current study assessed BDD symptoms in an ethnically diverse sample of adults (n=401) using an online survey. Participants completed self-report measures assessing BDD symptoms, body parts of concern and BDD behaviors. Compared to Caucasian participants, no significant differences were found in body parts or behaviors reported by Latino or African American participants. Significant group differences did emerge between Asian and Caucasian participants. Specifically, Asians reported more concern with straight hair and dark skin and fewer body shape concerns than Caucasians. Asians also endorsed lower rates of grooming, touching body parts, and camouflaging and higher rates of exercise compared to Caucasians. Although most clinical features of BDD appear similar across ethnic groups, results showed some differences in body parts and behaviors between Caucasians and Asian Americans with BDD symptoms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Preparation and Properties of New Inorganic Glasses and Gel-Derived Solids

DTIC Science & Technology

1991-04-01

route were examined, including the use of SiC and diamond powder as fillers and some triphasic , solids. Many ferroelectnic thin films were prepared...use of SiC and diamond powder as fillers and some triphasic solids. Many ferroelectric thin films were prepared and their properties measured. An...Exit Filter Mmrn Holder Filter He Gas Perforated Pyrolysis Reactor 00 0 00 00 00 00 0 0 0 0 Soutolution asWe Fi.8.Shmai darm fepeiena0yses I I I ci

Prevalence of Body Dysmorphic Disorder and Surgeon Diagnostic Accuracy in Facial Plastic and Oculoplastic Surgery Clinics.

PubMed

Joseph, Andrew W; Ishii, Lisa; Joseph, Shannon S; Smith, Jane I; Su, Peiyi; Bater, Kristin; Byrne, Patrick; Boahene, Kofi; Papel, Ira; Kontis, Theda; Douglas, Raymond; Nelson, Christine C; Ishii, Masaru

2017-07-01

Body dysmorphic disorder (BDD) is a relative contraindication for facial plastic surgery, but formal screening is not common in practice. The prevalence of BDD in patients seeking facial plastic surgery is not well documented. To establish the prevalence of BDD across facial plastic and oculoplastic surgery practice settings, and estimate the ability of surgeons to screen for BDD. This multicenter prospective study recruited a cohort of 597 patients who presented to academic and private facial plastic and oculoplastic surgery practices from March 2015 to February 2016. All patients were screened for BDD using the Body Dysmorphic Disorder Questionnaire (BDDQ). After each clinical encounter, surgeons independently evaluated the likelihood that a participating patient had BDD. Validated instruments were used to assess satisfaction with facial appearance including the FACE-Q, Blepharoplasty Outcomes Evaluation (BOE), Facelift Outcomes Evaluation (FOE), Rhinoplasty Outcomes Evaluation (ROE), and Skin Rejuvenation Outcomes Evaluation (SROE). Across participating practices (9 surgeons, 3 sites), a total of 597 patients were screened for BDD: 342 patients from site 1 (mean [SD] age, 44.2 [16.5] years); 158 patients, site 2 (mean [SD] age, 46.0 [16.2] years), site 3, 97 patients (mean [SD] age, 56.3 [15.5] years). Overall, 58 patients [9.7%] screened positive for BDD by the BDDQ instrument, while only 16 of 402 patients [4.0%] were clinically suspected of BDD by surgeons. A higher percentage of patients presenting for cosmetic surgery (37 of 283 patients [13.1%]) compared with those presenting for reconstructive surgery (21 of 314 patients [6.7%]) screened positive on the BDDQ (odds ratio, 2.10; 95% CI, 1.20-3.68; P = .01). Surgeons were only able to correctly identify 2 of 43 patients (4.7%) who screened positive for BDD on the BDDQ, and the positive likelihood ratio was only 1.19 (95% CI, 0.28-5.07). Patients screening positive for BDD by the BDDQ had lower satisfaction with their appearance as measured by the FACE-Q, ROE, BOE, SROE, and FOE. Body dysmorphic disorder is a relatively common condition across facial plastic and oculoplastic surgery practice settings. Patients who screen positive on the BDDQ have lower satisfaction with their facial appearance at baseline. Surgeons have a poor ability to screen for patients with BDD when compared with validated screening instruments such as the BDDQ. Routine implementation of validated BDD screening instruments may improve patient care. NA.

Surface Design and Engineering Toward Wear-Resistant, Self-Lubricating Diamond Films and Coatings

NASA Technical Reports Server (NTRS)

Miyoshi, Kazuhisa

1999-01-01

The tribological properties of chemical-vapor-deposited (CVD) diamond films vary with the environment, possessing a Jekyll-and-Hyde character. CVD diamond has low coefficient of friction and high wear resistance in air but high coefficient of friction and low wear resistance in vacuum. Improving the tribological functionality of materials (such as achieving low friction and good wear resistance) was an aim of this investigation. Three studies on the surface design, surface engineering, and tribology of CVD diamond have shown that its friction and wear are significantly reduced in ultrahigh vacuum. The main criteria for judging whether diamond films are an effective wear-resistant, self-lubricating material were coefficient of friction and wear rate, which must be less than 0.1 and on the order of 10(exp 6) cu mm/N(dot)m, respectively. In the first study the presence of a thin film (less than 1 micron thick) of amorphous, nondiamond carbon (hydrogenated carbon, also called diamondlike carbon or DLC) on CVD diamond greatly decreased the coefficient of friction and the wear rate. Therefore, a thin DLC film on CVD diamond can be an effective wear-resistant, lubricating coating in ultrahigh vacuum. In the second study the presence of an amorphous, nondiamond carbon surface layer formed on CVD diamond by ion implantation significantly reduced the coefficient of friction and the wear rate in ultrahigh vacuum. Therefore, such surface layers are acceptable for effective self-lubricating, wear-resistant applications of CVD diamond. In the third study CVD diamond in contact with cubic boron nitride exhibited low coefficient of friction in ultra high vacuum. Therefore, this materials combination can provide an effective self-lubricating, wear-resistant couple in ultrahigh vacuum.

Symptoms of muscle dysmorphia, body dysmorphic disorder, and eating disorders in a nonclinical population of adult male weightlifters in Australia.

PubMed

Nieuwoudt, Johanna E; Zhou, Shi; Coutts, Rosanne A; Booker, Ray

2015-05-01

The current study aimed to (a) determine the rates of symptoms of muscle dysmorphia (MD), body dysmorphic disorder (BDD), and eating disorder; (b) determine the relationships among symptoms of MD, BDD, and eating disorders; and (c) provide a comprehensive comparison of symptoms of MD, BDD, and eating disorders in a nonclinical population of adult male weightlifters in Australia. The participants (N = 648, mean age = 29.5 years, SD = 10.1) participated in an online survey, consisting of Muscle Appearance Satisfaction Scale, the Body Dysmorphic Disorder Questionnaire, and the Eating Attitude Test-26. Results indicated that 110 participants (17%) were at risk of having MD, 69 participants (10.6%) were at risk of having BDD, and 219 participants (33.8%) were at risk of having an eating disorder. Furthermore, 36 participants (5.6%) were found at risk of having both MD and BDD, and 60 participants (9.3%) were at risk of having both MD and an eating disorder. Significant correlations and associations were found between symptoms of MD and BDD, and symptoms of MD and eating disorders. Support was provided for the comorbidity of, and symptomatic similarities between, symptoms of MD and BDD, and symptoms of MD and eating disorders. This may reflect a shared pathogenesis between symptoms of MD, BDD, and eating disorders. Strength and conditioning professionals, exercise scientists, athletic trainers, and personal trainers should be aware that adult males who are working out with weights (i.e., free weights or machines) may be at increased risk of having MD, BDD, and eating disorders.

Attentional biases in body dysmorphic disorder (BDD): Eye-tracking using the emotional Stroop task.

PubMed

Toh, Wei Lin; Castle, David J; Rossell, Susan L

2017-04-01

Body dysmorphic disorder (BDD) is characterised by repetitive behaviours and/or mental acts occurring in response to preoccupations with perceived defects or flaws in physical appearance. This study aimed to examine attentional biases in BDD via the emotional Stroop task with two modifications: i) incorporating an eye-tracking paradigm, and ii) employing an obsessive-compulsive disorder (OCD) control group. Twenty-one BDD, 19 OCD and 21 HC participants, who were age-, sex-, and IQ-matched, were included. A card version of the emotional Stroop task was employed based on seven 10-word lists: (i) BDD-positive, (ii) BDD-negative, (iii) OCD-checking, (iv) OCD-washing, (v) general positive, (vi) general threat, and (vii) neutral (as baseline). Participants were asked to read aloud words and word colours consecutively, thereby yielding accuracy and latency scores. Eye-tracking parameters were also measured. Participants with BDD exhibited significant Stroop interference for BDD-negative words relative to HC participants, as shown by extended colour-naming latencies. In contrast, the OCD group did not exhibit Stroop interference for OCD-related nor general threat words. Only mild eye-tracking anomalies were uncovered in clinical groups. Inspection of individual scanning styles and fixation heat maps however revealed that viewing strategies adopted by clinical groups were generally disorganised, with avoidance of certain disorder-relevant words and considerable visual attention devoted to non-salient card regions. The operation of attentional biases to negative disorder-specific words was corroborated in BDD. Future replication studies using other paradigms are vital, given potential ambiguities inherent in emotional Stroop task interpretation. Copyright © 2017 Elsevier Inc. All rights reserved.

Body Dysmorphic Disorder: Some Key Issues for DSM-V

PubMed Central

Phillips, Katharine A.; Wilhelm, Sabine; Koran, Lorrin M.; Didie, Elizabeth R.; Fallon, Brian A.; Feusner, Jamie; Stein, Dan J.

2014-01-01

Body dysmorphic disorder (BDD), a distressing or impairing preoccupation with an imagined or slight defect in appearance, has been described for more than a century and increasingly studied over the past several decades. This paper provides a focused review of issues pertaining to BDD that are relevant to DSM-V. The review presents a number of options and preliminary recommendations to be considered for DSM-V: 1) Criterion A may benefit from some rewording, without changing its focus or meaning; 2) Potential disadvantages of adding a new criterion to reflect BDD compulsive behaviors seem to outweigh potential advantages, but adding such a criterion remains an option that can be considered; 3) A clinical significance criterion seems necessary for BDD to differentiate it from normal appearance concerns; 4) BDD and eating disorders have some overlapping features and need to be differentiated; some minor changes to DSM-IV’s criterion C are suggested; 5) BDD should not be broadened to include body integrity identity disorder (apotemnophilia) or olfactory reference syndrome; 6) There is no compelling evidence for including diagnostic features or subtypes that are specific to gender-related, age-related, or cultural manifestations of BDD; 7) Adding muscle dysmorphia as a specifier may have clinical utility; and 8) The ICD-10 criteria for hypochondriacal disorder are not suitable for BDD, and there is no empirical evidence that BDD and hypochondriasis are the same disorder. The issue of how BDD’s delusional variant should be classified in DSM-V is briefly discussed and will be addressed more extensively in a separate paper. PMID:20533368

A comparison of insight in body dysmorphic disorder and obsessive-compulsive disorder.

PubMed

Phillips, Katharine A; Pinto, Anthony; Hart, Ashley S; Coles, Meredith E; Eisen, Jane L; Menard, William; Rasmussen, Steven A

2012-10-01

Insight/delusionality of beliefs is an important dimension of psychopathology across psychiatric disorders. This construct is of increasing interest in obsessive-compulsive and related disorders, including obsessive-compulsive disorder (OCD) and body dysmorphic disorder (BDD). Even though OCD and BDD are considered closely related, no prior study has compared these disorders across a range of categories of global insight (excellent, good, fair, poor, absent/delusional), and only one study has compared these disorders on individual components of insight. Using the reliable and valid Brown Assessment of Beliefs Scale (BABS), this study examined insight/delusionality of OCD- or BDD-related beliefs in 211 individuals with primary OCD versus 68 individuals with primary BDD. In both disorders, levels of insight spanned the full range, from excellent to absent (i.e., delusional beliefs). However, the distribution of BABS scores across insight categories differed significantly by disorder, with the majority of OCD subjects showing excellent or good insight, and the majority of BDD subjects showing poor or absent insight. Compared to OCD subjects, BDD subjects had significantly poorer insight both overall (total BABS score) and on all individual BABS items. BABS score was significantly correlated with BDD and OCD severity, but in regressions it accounted for only 21% of the variance in OCD and 28% in BDD. In summary, both global insight and its individual components are poorer in BDD than in OCD, which has implications for research and clinical care, as well as understanding of the relationship between these disorders. Disorder severity is associated with but not equivalent to insight/delusionality. Copyright © 2012 Elsevier Ltd. All rights reserved.

Body dysmorphic disorder and psychological distress in orthognathic surgery patients.

PubMed

Collins, Brooke; Gonzalez, Daisy; Gaudilliere, Dyani Kalea; Shrestha, Puja; Girod, Sabine

2014-08-01

Body dysmorphic disorder (BDD) is a distressing condition involving preoccupation with an imagined or exaggerated deformity. The purpose of our study was to investigate the presence of BDD and its comorbidity with anxiety, depression, and obsessive-compulsive disorder (OCD) in patients undergoing orthognathic surgery (OS). The present prospective study included 99 patients from the outpatient oral and maxillofacial surgery clinic at Stanford University who requested OS. The incidence of BDD, depression, anxiety, and OCD was assessed preoperatively using validated self-report measures. To determine the prevalence of Axis I psychological symptoms among patients, the descriptive and bivariate statistics were computed. P < .05 was considered significant. In our sample, 13 patients (13%) screened positive for BDD. We did not find any significant correlations between the presence of BDD and gender, race, age, or marital status. Depressive symptoms were reported by 42% of the patients, OCD symptoms by 29%, and mild, moderate, and severe anxiety by 14%, 5%, and 4%, respectively. Using Spearman correlations, we found significant correlations between BDD and anxiety, depression, and OCD (P < .01). The results of the present study suggest that the rates of BDD, depression, anxiety, and OCD are high in patients undergoing OS. Furthermore, we found a strong correlation between BDD and anxiety, OCD, and depression in these patients. Future studies are necessary to determine the postoperative changes in these psychological disorders and whether these changes are affected by having positive BDD screening results at baseline. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Can understanding the neurobiology of body dysmorphic disorder (BDD) inform treatment?

PubMed

Rossell, Susan L; Harrison, Ben J; Castle, David

2015-08-01

We aim to provide a clinically focused review of the neurobiological literature in body dysmorphic disorder (BDD), with a focus on structural and functional neuroimaging. There has been a recent influx of studies examining the underlying neurobiology of BDD using structural and functional neuroimaging methods. Despite obvious symptom similarities with obsessive-compulsive disorder (OCD), no study to date has directly compared the two groups using neuroimaging techniques. Studies have established that there are limbic and visual cortex abnormalities in BDD, in contrast to fronto-striatal differences in OCD. Such data suggests affect or visual training maybe useful in BDD. © The Royal Australian and New Zealand College of Psychiatrists 2015.

The impact of comorbid body dysmorphic disorder on the response to sequential pharmacological trials for obsessive-compulsive disorder.

PubMed

Diniz, Juliana B; Costa, Daniel Lc; Cassab, Raony Cc; Pereira, Carlos Ab; Miguel, Euripedes C; Shavitt, Roseli G

2014-06-01

Our aim was to investigate the impact of comorbid body dysmorphic disorder (BDD) on the response to sequential pharmacological trials in adult obsessive-compulsive disorder (OCD) patients. The sequential trial initially involved fluoxetine monotherapy followed by one of three randomized, add-on strategies: placebo, clomipramine or quetiapine. We included 138 patients in the initial phase of fluoxetine, up to 80 mg or the maximum tolerated dosage, for 12 weeks. We invited 70 non-responders to participate in the add-on trial; as 54 accepted, we allocated 18 to each treatment group and followed them for an additional 12 weeks. To evaluate the combined effects of sex, age, age at onset, initial severity, type of augmentation and BDD on the response to sequential treatments, we constructed a model using generalized estimating equations (GEE). Of the 39 patients who completed the study (OCD-BDD, n = 13; OCD-non-BDD, n = 26), the OCD-BDD patients were less likely to be classified as responders than the OCD-non-BDD patients (Pearson Chi-Square = 4.4; p = 0.036). In the GEE model, BDD was not significantly associated with a worse response to sequential treatments (z-robust = 1.77; p = 0.07). The predictive potential of BDD regarding sequential treatment strategies for OCD did not survive when the analyses were controlled for other clinical characteristics. © The Author(s) 2013.

Electron Emission Observations from As-Grown and Vacuum-Coated Chemical Vapor Deposited Diamond

NASA Technical Reports Server (NTRS)

Lamouri, A.; Wang, Yaxin; Mearini, G. T.; Krainsky, I. L.; Dayton, J. A., Jr.; Mueller,W.

1996-01-01

Field emission has been observed from chemical vapor deposited diamond grown on Mo and Si substrates. Emission was observed at fields as low as 20 kV/cm. The samples were tested in the as-grown form, and after coating with thin films of Au, CsI, and Ni. The emission current was typically maximum at the onset of the applied field, but was unstable, and decreased rapidly with time from the as-grown films. Thin Au layers, approximately 15 nm thick, vacuum deposited onto the diamond samples significantly improved the stability of the emission current at values approximately equal to those from uncoated samples at the onset of the applied field. Thin layers of CsI, approximately 5 nm thick, were also observed to improve the stability of the emission current but at values less than those from the uncoated samples at the onset of the applied field. While Au and CsI improved the stability of the emission, Ni was observed to have no effect.

Deposition Of Cubic BN On Diamond Interlayers

NASA Technical Reports Server (NTRS)

Ong, Tiong P.; Shing, Yuh-Han

1994-01-01

Thin films of polycrystalline, pure, cubic boron nitride (c-BN) formed on various substrates, according to proposal, by chemical vapor deposition onto interlayers of polycrystalline diamond. Substrate materials include metals, semiconductors, and insulators. Typical substrates include metal-cutting tools: polycrystalline c-BN coats advantageous for cutting ferrous materials and for use in highly oxidizing environments-applications in which diamond coats tend to dissolve in iron or be oxidized, respectively.

Prevalence of body dysmorphic disorder on a psychiatric inpatient ward and the value of a screening question.

PubMed

Veale, David; Akyüz, Elvan U; Hodsoll, John

2015-12-15

The aim of this study was to estimate the prevalence of body dysmorphic disorder (BDD) on an inpatient ward in the UK with a larger sample than previously studied and to investigate the value of a simple screening question during an assessment interview. Four hundred and thirty two consecutive admissions were screened for BDD on an adult psychiatric ward over a period of 13 months. Those who screened positive had a structured diagnostic interview for BDD. The prevalence of BDD was estimated to be 5.8% (C.I. 3.6-8.1%). Our screening question had a slightly low specificity (76.6%) for detecting BDD. The strength of this study was a larger sample size and narrower confidence interval than previous studies. The study adds to previous observations that BDD is poorly identified in psychiatric inpatients. BDD was identified predominantly in those presenting with depression, substance misuse or an anxiety disorder. The screening question could be improved by excluding those with weight or shape concerns. Missing the diagnosis is likely to lead to inappropriate treatment. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Development of solar-driven electrochemical and photocatalytic water treatment system using a boron-doped diamond electrode and TiO2 photocatalyst.

PubMed

Ochiai, Tsuyoshi; Nakata, Kazuya; Murakami, Taketoshi; Fujishima, Akira; Yao, Yanyan; Tryk, Donald A; Kubota, Yoshinobu

2010-02-01

A high-performance, environmentally friendly water treatment system was developed. The system consists mainly of an electrochemical and a photocatalytic oxidation unit, with a boron-doped diamond (BDD) electrode and TiO(2) photocatalyst, respectively. All electric power for the mechanical systems and the electrolysis was able to be provided by photovoltaic cells. Thus, this system is totally driven by solar energy. The treatment ability of the electrolysis and photocatalysis units was investigated by phenol degradation kinetics. An observed rate constant of 5.1 x 10(-3)dm(3)cm(-2)h(-1) was calculated by pseudo-first-order kinetic analysis for the electrolysis, and a Langmuir-Hinshelwood rate constant of 5.6 microM(-1)min(-1) was calculated by kinetic analysis of the photocatalysis. According to previous reports, these values are sufficient for the mineralization of phenol. In a treatment test of river water samples, large amounts of chemical and biological contaminants were totally wet-incinerated by the system. This system could provide 12L/day of drinking water from the Tama River using only solar energy. Therefore, this system may be useful for supplying drinking water during a disaster. (c) 2009 Elsevier Ltd. All rights reserved.

Electrochemical degradation of the antihypertensive losartan in aqueous medium by electro-oxidation with boron-doped diamond electrode.

PubMed

Salazar, Claudio; Contreras, Nicole; Mansilla, Héctor D; Yáñez, Jorge; Salazar, Ricardo

2016-12-05

In this work the electrochemical oxidation of losartan, an emerging pharmaceutical pollutant, was studied. Electrochemical oxidation was carried out in batch mode, in an open and undivided cell of 100cm(3) using a boron-doped diamond (BDD)/stainless steel system. With Cl(-) medium 56% of mineralization was registered, while with the trials containing SO4(2-) as supporting electrolyte a higher mineralization yield of 67% was reached, even obtaining a total removal of losartan potassium at 80mAcm(-2) and 180min of reaction time at pH 7.0. Higher losartan potassium concentrations enhanced the mineralization degree and the efficiency of the electrochemical oxidation process. During the mineralization up to 4 aromatic intermediates were identified by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Moreover, short-linear carboxylic acids, like oxalic, succinic and oxamic were detected and quantified by ion-exclusion HPLC. Finally, the ability of the electrochemical oxidation process to mineralize dissolved commercial tablets containing losartan was achieved, obtaining TOC removal up to 71% under optimized conditions (10mAcm(-2), 0.05M Na2SO4, pH 7.0 and 25°C and 360min of electrolysis). Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular Signature of Pseudomonas aeruginosa with Simultaneous Nanomolar Detection of Quorum Sensing Signaling Molecules at a Boron-Doped Diamond Electrode

PubMed Central

Buzid, Alyah; Shang, Fengjun; Reen, F. Jerry; Muimhneacháin, Eoin Ó; Clarke, Sarah L.; Zhou, Lin; Luong, John H. T.; O’Gara, Fergal; McGlacken, Gerard P.; Glennon, Jeremy D.

2016-01-01

Electroanalysis was performed using a boron-doped diamond (BDD) electrode for the simultaneous detection of 2-heptyl-3-hydroxy-4-quinolone (PQS), 2-heptyl-4-hydroxyquinoline (HHQ) and pyocyanin (PYO). PQS and its precursor HHQ are two important signal molecules produced by Pseudomonas aeruginosa, while PYO is a redox active toxin involved in virulence and pathogenesis. This Gram-negative and opportunistic human pathogen is associated with a hospital-acquired infection particularly in patients with compromised immunity and is the primary cause of morbidity and mortality in cystic fibrosis (CF) patients. Early detection is crucial in the clinical management of this pathogen, with established infections entering a biofilm lifestyle that is refractory to conventional antibiotic therapies. Herein, a detection procedure was optimized and proven for the simultaneous detection of PYO, HHQ and PQS in standard mixtures, biological samples, and P. aeruginosa spiked CF sputum samples with remarkable sensitivity, down to nanomolar levels. Differential pulse voltammetry (DPV) scans were also applicable for monitoring the production of PYO, HHQ and PQS in P. aeruginosa PA14 over 8 h of cultivation. The simultaneous detection of these three compounds represents a molecular signature specific to this pathogen. PMID:27427496

Pharmacotherapy Relapse Prevention in Body Dysmorphic Disorder: A Double-Blind Placebo-Controlled Trial

PubMed Central

Phillips, Katharine A.; Keshaviah, Aparna; Dougherty, Darin; Stout, Robert L.; Menard, William; Wilhelm, Sabine

2016-01-01

Objective Body dysmorphic disorder (BDD) is common, distressing, and often severely impairing. Serotonin-reuptake inhibitors (SRIs) appear efficacious for BDD, but the few existing pharmacotherapy studies were short-term (≤4 months), and no relapse prevention studies or continuation phase studies have been conducted. We report results from the first BDD relapse prevention study. Method Adults (N=100) with DSM-IV BDD received open-label escitalopram for 14 weeks (Phase 1); 58 responders were then randomized to double-blind continuation treatment with escitalopram versus switch to placebo for six months (Phase 2). Reliable and valid outcome measures were utilized. Results Phase 1: Overall, 67.0% of treated subjects and 81.1% of completers were escitalopram responders (p’s<0.0001). BDD severity, BDD-related insight, depressive symptoms, psychosocial functioning, and quality of life significantly improved from baseline to end of Phase 1 (all p's<0.0001). Phase 2: Time to relapse was significantly longer for subjects receiving escitalopram than those receiving placebo (hazard ratio=2.72, 95% CI [1.01, 8.57], p=0.049). Phase 2 relapse proportions were 18% for escitalopram versus 40% for placebo. In escitalopram-treated subjects, BDD severity significantly decreased over time during the continuation treatment phase (p=0.036); further improvement occurred in 35.7% of the escitalopram group. There were no significant group differences in BDD severity, insight, depressive symptoms, psychosocial functioning, or quality of life. Conclusions Continuation-phase escitalopram delayed time to relapse, and fewer escitalopram-treated subjects relapsed compared with placebo-treated subjects. BDD severity significantly further improved during six additional months of escitalopram treatment following acute response; more than one-third of escitalopram-treated subjects had further improvement during continuation phase treatment. PMID:27056606

Visual information processing of faces in body dysmorphic disorder.

PubMed

Feusner, Jamie D; Townsend, Jennifer; Bystritsky, Alexander; Bookheimer, Susan

2007-12-01

Body dysmorphic disorder (BDD) is a severe psychiatric condition in which individuals are preoccupied with perceived appearance defects. Clinical observation suggests that patients with BDD focus on details of their appearance at the expense of configural elements. This study examines abnormalities in visual information processing in BDD that may underlie clinical symptoms. To determine whether patients with BDD have abnormal patterns of brain activation when visually processing others' faces with high, low, or normal spatial frequency information. Case-control study. University hospital. Twelve right-handed, medication-free subjects with BDD and 13 control subjects matched by age, sex, and educational achievement. Intervention Functional magnetic resonance imaging while performing matching tasks of face stimuli. Stimuli were neutral-expression photographs of others' faces that were unaltered, altered to include only high spatial frequency visual information, or altered to include only low spatial frequency visual information. Blood oxygen level-dependent functional magnetic resonance imaging signal changes in the BDD and control groups during tasks with each stimulus type. Subjects with BDD showed greater left hemisphere activity relative to controls, particularly in lateral prefrontal cortex and lateral temporal lobe regions for all face tasks (and dorsal anterior cingulate activity for the low spatial frequency task). Controls recruited left-sided prefrontal and dorsal anterior cingulate activity only for the high spatial frequency task. Subjects with BDD demonstrate fundamental differences from controls in visually processing others' faces. The predominance of left-sided activity for low spatial frequency and normal faces suggests detail encoding and analysis rather than holistic processing, a pattern evident in controls only for high spatial frequency faces. These abnormalities may be associated with apparent perceptual distortions in patients with BDD. The fact that these findings occurred while subjects viewed others' faces suggests differences in visual processing beyond distortions of their own appearance.

Contribution of bile duct drainage on resource use and clinical outcome of open or laparoscopic cholecystectomy in Japan.

PubMed

Kuwabara, Kazuaki; Matsuda, Shinya; Fushimi, Kiyohide; Ishikawa, Koichi B; Horiguchi, Hiromasa; Hayashida, Kenshi; Fujimori, Kenji

2010-02-01

Laparoscopic cholecystectomy (LC) is replacing conventional open cholecystectomy (OC) as a preferred surgical method for treating complicated biliary tract disorders. However, there have been few studies assessing the impact of staged bile duct drainage (BDD) on costs and clinical outcomes for either surgical approach. This study evaluated the impact of surgical technique and BDD on resource utilization and complication rates. This study included 2778 cholecystectomy patients treated for benign biliary tract diseases in 80 academic and 81 community hospitals. For both OC and LC patients, the following variables were analysed: demographics, clinical data, length of stay (LOS), total charges (TC; US$), procedure-related complications and hospital type. Multivariate analyses were used to determine the impact of BDD on LOS, TC and complication rates. Of the 2778 cholecystectomy patients in the study, 2255 (81.2%) underwent LC. Inflammation was diagnosed in 55.6% of OC patients and 36.0% of LC patients. Complication was 9.4% in OC cases and 4.7% in LC cases. BDD was performed in 14.5% of OC cases and in 7.6% of LC cases. Diagnosis of inflammation, presence of co-morbidities and BDD each had a significant impact on LOS and TC. After risk adjustment, LC was associated with a reduction in LOS and TC, while BDD resulted in greater LOS and TC. LC and BDD were significantly associated with complications. The study suggested that BDD utilized more resources and had higher rates of complications. LC remains an appropriate procedure for cholecystectomy patients. Further study will be needed to evaluate the effect of pre-operative or post-operative BDD on quality of care.

Degradation of pharmaceutical beta-blockers by electrochemical advanced oxidation processes using a flow plant with a solar compound parabolic collector.

PubMed

Isarain-Chávez, Eloy; Rodríguez, Rosa María; Cabot, Pere Lluís; Centellas, Francesc; Arias, Conchita; Garrido, José Antonio; Brillas, Enric

2011-08-01

The degradation of the beta-blockers atenolol, metoprolol tartrate and propranolol hydrochloride was studied by electro-Fenton (EF) and solar photoelectro-Fenton (SPEF). Solutions of 10 L of 100 mg L⁻¹ of total organic carbon of each drug in 0.1 M Na₂SO₄ with 0.5 mM Fe²⁺ of pH 3.0 were treated in a recirculation flow plant with an electrochemical reactor coupled with a solar compound parabolic collector. Single Pt/carbon felt (CF) and boron-doped diamond (BDD)/air-diffusion electrode (ADE) cells and combined Pt/ADE-Pt/CF and BDD/ADE-Pt/CF cells were used. SPEF treatments were more potent with the latter cell, yielding 95-97% mineralization with 100% of maximum current efficiency and energy consumptions of about 0.250 kWh g TOC⁻¹. However, the Pt/ADE-Pt/CF cell gave much lower energy consumptions of about 0.080 kWh g TOC⁻¹ with slightly lower mineralization of 88-93%, then being more useful for its possible application at industrial level. The EF method led to a poorer mineralization and was more potent using the combined cells by the additional production of hydroxyl radicals (•OH) from Fenton's reaction from the fast Fe²⁺ regeneration at the CF cathode. Organics were also more rapidly destroyed at BDD than at Pt anode. The decay kinetics of beta-blockers always followed a pseudo first-order reaction, although in SPEF, it was accelerated by the additional production of •OH from the action of UV light of solar irradiation. Aromatic intermediates were also destroyed by hydroxyl radicals. Ultimate carboxylic acids like oxalic and oxamic remained in the treated solutions by EF, but their Fe(III) complexes were photolyzed by solar irradiation in SPEF, thus explaining its higher oxidation power. NO₃⁻ was the predominant inorganic ion lost in EF, whereas the SPEF process favored the production of NH₄⁺ ion and volatile N-derivatives. Copyright © 2011 Elsevier Ltd. All rights reserved.

Relationship between Social Anxiety Disorder and Body Dysmorphic Disorder

PubMed Central

Fang, Angela; Hofmann, Stefan G.

2010-01-01

Social anxiety disorder (SAD) and body dysmorphic disorder (BDD) are two separate, but conceptually overlapping nosological entities. In this review, we examine similarities between SAD and BDD in comorbidity, phenomenology, cognitive biases, treatment outcome, and cross-cultural aspects. Our review suggests that SAD and BDD are highly comorbid, show a similar age of onset, share a chronic trajectory, and show similar cognitive biases for interpreting ambiguous social information in a negative manner. Furthermore, research from treatment outcome studies have demonstrated that improvements in SAD were significantly correlated with improvements in BDD. Findings from cross-cultural research suggest that BDD may be conceived as a subtype of SAD in some Eastern cultures. Directions for future research and clinical implications of these findings are discussed. PMID:20817336

Suicidality in Body Dysmorphic Disorder: A Prospective Study

PubMed Central

Phillips, Katharine A.; Menard, William

2006-01-01

Objective Cross-sectional/retrospective data have indicated that individuals with body dysmorphic disorder (BDD) have high rates of suicidal ideation and attempts. However, no study, to the authors' knowledge, has prospectively examined suicidality in BDD. Method In the first prospective study of BDD's course, the authors examined suicidality in 185 subjects for up to 4 years. Results Suicidal ideation was reported by a mean of 57.8% of the subjects per year, and a mean of 2.6% attempted suicide per year. Two subjects (0.3% per year) completed suicide. Conclusions Individuals with BDD have high rates of suicidal ideation and attempts. The completed suicide rate is preliminary but suggests that the rate of completed suicide in BDD is markedly high. PMID:16816236

Effect of slurry composition on the chemical mechanical polishing of thin diamond films

PubMed Central

Werrell, Jessica M.; Mandal, Soumen; Thomas, Evan L. H.; Brousseau, Emmanuel B.; Lewis, Ryan; Borri, Paola; Davies, Philip R.; Williams, Oliver A.

2017-01-01

Nanocrystalline diamond (NCD) thin films grown by chemical vapour deposition have an intrinsic surface roughness, which hinders the development and performance of the films’ various applications. Traditional methods of diamond polishing are not effective on NCD thin films. Films either shatter due to the combination of wafer bow and high mechanical pressures or produce uneven surfaces, which has led to the adaptation of the chemical mechanical polishing (CMP) technique for NCD films. This process is poorly understood and in need of optimisation. To compare the effect of slurry composition and pH upon polishing rates, a series of NCD thin films have been polished for three hours using a Logitech Ltd. Tribo CMP System in conjunction with a polyester/polyurethane polishing cloth and six different slurries. The reduction in surface roughness was measured hourly using an atomic force microscope. The final surface chemistry was examined using X-ray photoelectron spectroscopy and a scanning electron microscope. It was found that of all the various properties of the slurries, including pH and composition, the particle size was the determining factor for the polishing rate. The smaller particles polishing at a greater rate than the larger ones. PMID:29057022

Effect of slurry composition on the chemical mechanical polishing of thin diamond films

NASA Astrophysics Data System (ADS)

Werrell, Jessica M.; Mandal, Soumen; Thomas, Evan L. H.; Brousseau, Emmanuel B.; Lewis, Ryan; Borri, Paola; Davies, Philip R.; Williams, Oliver A.

2017-12-01

Nanocrystalline diamond (NCD) thin films grown by chemical vapour deposition have an intrinsic surface roughness, which hinders the development and performance of the films' various applications. Traditional methods of diamond polishing are not effective on NCD thin films. Films either shatter due to the combination of wafer bow and high mechanical pressures or produce uneven surfaces, which has led to the adaptation of the chemical mechanical polishing (CMP) technique for NCD films. This process is poorly understood and in need of optimisation. To compare the effect of slurry composition and pH upon polishing rates, a series of NCD thin films have been polished for three hours using a Logitech Ltd. Tribo CMP System in conjunction with a polyester/polyurethane polishing cloth and six different slurries. The reduction in surface roughness was measured hourly using an atomic force microscope. The final surface chemistry was examined using X-ray photoelectron spectroscopy and a scanning electron microscope. It was found that of all the various properties of the slurries, including pH and composition, the particle size was the determining factor for the polishing rate. The smaller particles polishing at a greater rate than the larger ones.

Anxiety and Shame as Risk Factors for Depression, Suicidality, and Functional Impairment in Body Dysmorphic Disorder and Obsessive Compulsive Disorder.

PubMed

Weingarden, Hilary; Renshaw, Keith D; Wilhelm, Sabine; Tangney, June P; DiMauro, Jennifer

2016-11-01

Body dysmorphic disorder (BDD) and obsessive compulsive disorder (OCD) are associated with elevated depression, suicidality, functional impairment, and days housebound, yet little research has identified risk factors for these outcomes. Using path analysis, the present study examined anxiety and shame as risk factors for these outcomes across Internet-recruited self-report groups (BDD [n = 114], OCD [n = 114], and healthy control [HC; n = 133]). Paths from anxiety and shame to outcomes were similar and mostly significant across BDD and OCD, compared to non-significant paths for HCs, with one exception: the path from shame to depression was significant in the BDD group (b = 0.32) but non-significant in the OCD group (b = 0.07). Findings underscore similarities in BDD and OCD, supporting their reclassification into the same Obsessive Compulsive Related Disorders category. Results emphasize the importance of targeting shame, in addition to anxiety, in treatments for BDD and OCD.

Anxiety and Shame as Risk Factors for Depression, Suicidality, and Functional Impairment in Body Dysmorphic Disorder and Obsessive Compulsive Disorder

PubMed Central

Weingarden, Hilary; Renshaw, Keith D.; Wilhelm, Sabine; Tangney, June P.; DiMauro, Jennifer

2016-01-01

Body dysmorphic disorder (BDD) and obsessive compulsive disorder (OCD) are associated with elevated depression, suicidality, functional impairment, and days housebound, yet little research has identified risk factors for these outcomes. Using path analysis, the present study examined anxiety and shame as risk factors for these outcomes across Internet-recruited self-report groups (BDD [n = 114], OCD [n = 114], and healthy control [HC; n = 133]. Paths from anxiety and shame to outcomes were similar and mostly significant across BDD and OCD, compared to non-significant paths for HCs, with one exception: the path from shame to depression was significant in the BDD group (b = .32) but non-significant in the OCD group (b = .07). Findings underscore similarities in BDD and OCD, supporting their reclassification into the same Obsessive Compulsive Related Disorders category. Results emphasize the importance of targeting shame, in addition to anxiety, in treatments for BDD and OCD. PMID:26998694

Relationship between self-discrepancy and worries about penis size in men with body dysmorphic disorder.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Bramley, Sally; Troglia, Andrea; Carmona, Lina; Fiorito, Chiara; Wells, Hannah; Wylie, Kevan; Muir, Gordon

2016-06-01

We explored self-discrepancy in men with body dysmorphic disorder (BDD) concerned about penis size, men without BDD but anxious about penis size, and controls. Men with BDD (n=26) were compared to those with small penis anxiety (SPA; n=31) and controls (n=33), objectively (by measuring) and investigating self-discrepancy: actual size, ideal size, and size they felt they should be according to self and other. Most men under-estimated their penis size, with the BDD group showing the greatest discrepancy between perceived and ideal size. The SPA group showed a larger discrepancy than controls. This was replicated for the perceptions of others, suggesting the BDD group internalised the belief that they should have a larger penis size. There was a significant correlation between symptoms of BDD and this discrepancy. This self-actual and self-ideal/self-should discrepancy and the role of comparing could be targeted in therapy. Copyright © 2016. Published by Elsevier Ltd.

The Prevalence of Body Dysmorphic Disorder in Patients Undergoing Cosmetic Surgery: a Systematic Review.

PubMed

Panayi, Andreana

2015-09-01

Body dysmorphic disorder (BDD) is a somatoform disorder characterised by a distressing obsession with an imagined or slight appearance defect, which can significantly impair normal day-to-day functioning. Patients with BDD often first present, and are hence diagnosed, in cosmetic surgery settings. Several studies have investigated the prevalence rate of BDD in the general population or have done so for patients referring to cosmetic medical centers. To date, however, no review has been undertaken to compare the prevalence in the general community versus in a cosmetic surgery setting. Despite the lack of such a review it is a commonly held belief that BDD is more common in patients seeking cosmetic surgery. The current study aims to review the available literature in order to investigate whether BDD is indeed more prevalent in patients requesting cosmetic surgery, and if that is the case, to provide possible reasons for the difference in prevalence. In addition this review provides evidence on the effectiveness of cosmetic surgery as a treatment of BDD.

Emotion recognition in body dysmorphic disorder: application of the Reading the Mind in the Eyes Task.

PubMed

Buhlmann, Ulrike; Winter, Anna; Kathmann, Norbert

2013-03-01

Body dysmorphic disorder (BDD) is characterized by perceived appearance-related defects, often tied to aspects of the face or head (e.g., acne). Deficits in decoding emotional expressions have been examined in several psychological disorders including BDD. Previous research indicates that BDD is associated with impaired facial emotion recognition, particularly in situations that involve the BDD sufferer him/herself. The purpose of this study was to further evaluate the ability to read other people's emotions among 31 individuals with BDD, and 31 mentally healthy controls. We applied the Reading the Mind in the Eyes task, in which participants are presented with a series of pairs of eyes, one at a time, and are asked to identify the emotion that describes the stimulus best. The groups did not differ with respect to decoding other people's emotions by looking into their eyes. Findings are discussed in light of previous research examining emotion recognition in BDD. Copyright © 2013. Published by Elsevier Ltd.

Body dysmorphic disorder in patients undergoing septorhinoplasty surgery: should we be performing routine screening?

PubMed

Joseph, J; Randhawa, P; Hannan, S A; Long, J; Goh, S; O'Shea, N; Saleh, H; Hansen, E; Veale, D; Andrews, P

2017-06-01

Body dysmorphic disorder (BDD) is defined as having a preoccupation with a perceived flaw in one's appearance, which appears slight to others and significantly interferes with a person's functioning. When undetected in septorhinoplasty patients, it will often lead to poor outcomes. We performed a prospective cohort study to determine the prevalence of BDD in our patients and whether surgical correction could be considered. We recruited 34 patients being considered for septorhinoplasty in a tertiary referral rhinology clinic and a control group of 50 from the otology clinic giving a total of 84. Participants completed the Body Dysmorphic Disorder Questionnaire (BDDQ), the sino-nasal outcome test-23 (SNOT-23) and underwent nasal inspiratory peak flow (NIPF). Those found to be at high risk for BDD were referred to a clinical psychologist. Of the septorhinoplasty patients, 11 (32%) were high risk for BDD. Following psychological assessment, 7 (63%) patients were felt to be unsuitable for surgery and were offered psychological therapy. SNOT-23 scores were significantly higher in the BDD group indicating a negative impact on quality of life. NIPF readings were not significantly different in the BDD group compared to the control group. The BDDQ is a valid tool for identifying patients at risk of BDD. A close working relationship with clinical psychology has been advantageous to help the selection process of candidates for surgery when there is a high risk of BDD. © 2016 John Wiley & Sons Ltd.

Progress in the characterization of diamond thin films prepared by a laser plasma discharge

NASA Astrophysics Data System (ADS)

Davanloo, F.; Juengerman, E. M.; Jander, D. R.; Lee, T. J.; Collins, C. B.

Progress in the characterization of diamond thin films produced by a unique laser plasma discharge source at practical growth rates of 0.7 micron/hr is reported. Optical properties, mass densities, and electrical resistivities of deposited films are given and their relationship to the power density of the laser at the graphite target is discussed. Examination of films with scanning tunneling microscopy show the clear prevalence of the structure recently predicted by Angus et al. (1990) in which sp3 clusters are bonded together with the carbon polytypes.

Body Dysmorphic Disorder: Neurobiological Features and an Updated Model

PubMed Central

Li, Wei; Arienzo, Donatello; Feusner, Jamie D.

2013-01-01

Body Dysmorphic Disorder (BDD) affects approximately 2% of the population and involves misperceived defects of appearance along with obsessive preoccupation and compulsive behaviors. There is evidence of neurobiological abnormalities associated with symptoms in BDD, although research to date is still limited. This review covers the latest neuropsychological, genetic, neurochemical, psychophysical, and neuroimaging studies and synthesizes these findings into an updated (yet still preliminary) neurobiological model of the pathophysiology of BDD. We propose a model in which visual perceptual abnormalities, along with frontostriatal and limbic system dysfunction, may combine to contribute to the symptoms of impaired insight and obsessive thoughts and compulsive behaviors expressed in BDD. Further research is necessary to gain a greater understanding of the etiological formation of BDD symptoms and their evolution over time. PMID:25419211

Neural activity to intense positive versus negative stimuli can help differentiate bipolar disorder from unipolar major depressive disorder in depressed adolescents: a pilot fMRI study.

PubMed

Diler, Rasim Somer; de Almeida, Jorge Renner Cardoso; Ladouceur, Cecile; Birmaher, Boris; Axelson, David; Phillips, Mary

2013-12-30

Failure to distinguish bipolar depression (BDd) from the unipolar depression of major depressive disorder (UDd) in adolescents has significant clinical consequences. We aimed to identify differential patterns of functional neural activity in BDd versus UDd and employed two (fearful and happy) facial expression/ gender labeling functional magnetic resonance imaging (fMRI) experiments to study emotion processing in 10 BDd (8 females, mean age=15.1 ± 1.1) compared to age- and gender-matched 10 UDd and 10 healthy control (HC) adolescents who were age- and gender-matched to the BDd group. BDd adolescents, relative to UDd, showed significantly lower activity to both intense happy (e.g., insula and temporal cortex) and intense fearful faces (e.g., frontal precentral cortex). Although the neural regions recruited in each group were not the same, both BDd and UDd adolescents, relative to HC, showed significantly lower neural activity to intense happy and mild happy faces, but elevated neural activity to mild fearful faces. Our results indicated that patterns of neural activity to intense positive and negative emotional stimuli can help differentiate BDd from UDd in adolescents. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Laser patterning of diamond films

NASA Astrophysics Data System (ADS)

Narayan, J.; Chen, X.

1992-04-01

Selective deposition and fine-scale patterning of hot filament deposited diamond films by the use of pulsed laser irradiation on silicon and copper substrates are reported. The substrates were abraded with diamond and alumina powders before hot-filament chemical vapor deposition. A drastic enhancement in diamond nucleation (using hot-filament chemical vapor deposition) was observed on specimens treated with diamond powder, whereas enhancement on specimens pretreated with alumina powder was relatively insignificant. It is found that the seeding of diamond crystals was substantially reduced by pulsed laser annealing/melting which removes the plastic damage as well as the seed crystals introduced by diamond powder pretreatment. The selective deposition or fine-scale patterning of diamond films was achieved either by a shadow masking or by scanning a focused laser beam to generate desired patterns. The nucleation can also be enhanced by laser deposition of thin films, such as diamond-like carbon and tungsten carbide (WC), and selective deposition and patterning achieved by controlled removal or deposition of the above films.

EFFECTS OF LASER RADIATION ON MATTER. LASER PLASMA: Selective metallisation of diamonds with the aid of laser radiation

NASA Astrophysics Data System (ADS)

Shafeev, Georgii A.; Pimenov, S. M.; Lubnin, Evgenii N.; Smolin, A. A.; Konov, Vitalii I.; Laptev, V. A.

1995-02-01

An experimental investigation was made of laser activation of diamond surfaces (single crystals and polycrystalline diamond films) prior to electroless before catalytic deposition of metals from solutions. The activation was carried out by a copper vapour laser or a KrF excimer laser in two ways: decomposition of a thin film of palladium acetylacetonate and local laser stimulated modification of the diamond surface by laser evaporation. An ohmic contact (Cu or Ni) with an adhesive strength of 3 N mm-2 was formed and the spatial resolution achieved was 10 μm.

Comorbidity between obsessive-compulsive disorder and body dysmorphic disorder: prevalence, explanatory theories, and clinical characterization

PubMed Central

Frías, Álvaro; Palma, Carol; Farriols, Núria; González, Laura

2015-01-01

Background With the advent of the fifth edition of Diagnostic and Statistical Manual of Mental Disorders, body dysmorphic disorder (BDD) has been subsumed into the obsessive-compulsive disorders and related disorders (OCDRD) category. Objective We aimed to determine the empirical evidence regarding the potential relationship between BDD and obsessive-compulsive disorder (OCD) based on the prevalence data, etiopathogenic pathways, and clinical characterization of patients with both disorders. Method A comprehensive search of databases (PubMed and PsycINFO) was performed. Published manuscripts between 1985 and May 2015 were identified. Overall, 53 studies fulfilled inclusion criteria. Results Lifetime comorbidity rates of BDD–OCD are almost three times higher in samples with a primary diagnosis of BDD than those with primary OCD (27.5% vs 10.4%). However, other mental disorders, such as social phobia or major mood depression, are more likely among both types of psychiatric samples. Empirical evidence regarding the etiopathogenic pathways for BDD–OCD comorbidity is still inconclusive, whether concerning common shared features or one disorder as a risk factor for the other. Specifically, current findings concerning third variables show more divergences than similarities when comparing both disorders. Preliminary data on the clinical characterization of the patients with BDD and OCD indicate that the deleterious clinical impact of BDD in OCD patients is greater than vice versa. Conclusion Despite the recent inclusion of BDD within the OCDRD, data from comparative studies between BDD and OCD need further evidence for supporting this nosological approach. To better define this issue, comparative studies between BDD, OCD, and social phobia should be carried out. PMID:26345330

The frequency of body dysmorphic disorder in dermatology and cosmetic dermatology clinics: a study from Turkey.

PubMed

Dogruk Kacar, S; Ozuguz, P; Bagcioglu, E; Coskun, K S; Uzel Tas, H; Polat, S; Karaca, S

2014-06-01

Body dysmorphic disorder (BDD) is a distressing and impairing preoccupation with a slight or imagined defect in appearance. There are few reports on the prevalence of BDD in the Turkish population. To investigate the frequency of BDD in dermatology settings, and to compare the results from cosmetic dermatology with those from general dermatology settings. This cross-sectional study recruited 400 patients from cosmetic dermatology (CD) (n = 200) and general dermatology (GD) clinics (n = 200). A mini-survey was used to collect demographic and clinical characteristics, and the dermatology version of a brief self-report BDD screening questionnaire was administered. A five-point Likert scale was used for objective scoring of the stated concern, which was performed by dermatologists, and patients who scored ≥ 3 were excluded from the study. In total, 318 patients (151 in the CD group and 167 in the GD group) completed the study, and of these, 20 were diagnosed with BDD. The CD group had a higher rate of BDD (8.6%) than the GD group (4.2%) but this was not significant (P = 0.082). The major concern focused on body and weight (40.0%), followed by acne (25.0%). The number of cosmetic procedures in dermatology practices is increasing Therefore, it is becoming more important to recognize patients with BDD. Although the rates of BDD found in the present study are in agreement with the literature data, population-based differences still exist between this study and previous studies. © 2014 British Association of Dermatologists.

Method for the preparation of nanocrystalline diamond thin films

DOEpatents

Gruen, Dieter M.; Krauss, Alan R.

1998-01-01

A method and system for manufacturing nanocrystalline diamond film on a substrate such as field emission tips. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrocarbon and possibly hydrogen, and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous vapor and deposition of a diamond film on the field emission tip.

3-D X-ray tomography of diamondiferous mantle eclogite xenoliths, Siberia: A review

NASA Astrophysics Data System (ADS)

Howarth, Geoffrey H.; Sobolev, Nikolay V.; Pernet-Fisher, John F.; Ketcham, Richard A.; Maisano, Jessica A.; Pokhilenko, Lyudmila N.; Taylor, Dawn; Taylor, Lawrence A.

2015-04-01

Diamonds form over billions of years, hundreds of kilometers beneath the Earth's surface, and in combination with inclusions trapped within, provide important constraints on the evolution of the mantle over geological time. Diamonds are generally studied as individual crystals sourced from highly explosive kimberlite pipes, which entrain and subsequently disaggregate mantle fragments (xenoliths) en route to the surface. This has resulted in a general absence of robust textural descriptions of diamonds relative to their hosting mantle protolith. The textural associations of diamonds within their mantle host rocks are reviewed here on the basis of a compilation of X-ray tomographic data for 17 diamondiferous eclogite xenoliths from Siberian kimberlites. This review represents a comprehensive description of diamonds relative to their host silicates. The lack of such descriptions in previous studies is largely due to the rarity of these xenoliths, the difficulty in preparing petrographic thin sections containing diamonds, and their high-monetary value. High-resolution computed X-ray tomography (HRCXT) produces up to 1200 sequential 2-D slices through individual xenoliths, each of which represents a 'pseudo thin-section' with a resolution on the order of 5-20 μm. The improved resolution of X-ray imaging in recent studies allows for the identification of not only primary minerals, but metasomatic minerals assemblages, including: 'spongy' textured clinopyroxene, phlogopite/K-richterite, and hercynitic spinel, allowing for the delineation of distinct metasomatic pathways through the xenoliths and their relationship to diamonds. Diamonds are observed in three distinct textural settings, potentially representing several temporally distinct diamond growth events, these setting includes: (1) diamonds completely enclosed in garnet; (2) diamonds associated with highly embayed silicate grain boundaries; and (3) diamonds contained within distinct metasomatic 'plumbing-systems'. Diamonds observed completely enclosed in garnets suggest an early diamond-forming event prior to major re-crystallization and eclogite formation during subduction. The occurrence of diamond in association with embayed garnets suggests that diamond grew at the expense of the hosting silicate protolith. In addition, the spatial relationships of diamonds with metasomatic pathways, which are generally interpreted to result from late-stage proto-kimberlitic fluid percolation, indicate a period of diamond growth occurring close to, but prior to, the time of kimberlite emplacement. Furthermore, the paragenesis of sulfides within eclogite xenoliths are described using 3-D models for entire xenoliths volumes, providing important constraints of the timing of sulfide mobilization within the mantle. Three-D animations created using X-ray tomography data for ten of the xenoliths can be viewed at the following link: http://eps.utk.edu/faculty/taylor/tomography.php

Prevalence of body dysmorphic disorder and associated features in German adolescents: A self-report survey.

PubMed

Möllmann, Anne; Dietel, Fanny A; Hunger, Antje; Buhlmann, Ulrike

2017-08-01

Prior research has not yet investigated the prevalence of body dysmorphic disorder (BDD) in adolescents and young adults based on criteria from the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5). In the current study, the point prevalence of BDD, comorbid symptoms, and associated features, such as appearance-related suicidality, level of insight or history of plastic surgeries, were examined in a non-clinical sample of German adolescents and young adults (n=308), between 15 and 21 years old, using self-report measures. Eleven participants (3.6%; 95% CI=[1.9, 5.8]) met DSM-5 criteria for BDD. Self-reported BDD (vs. no-BDD) was related to respondents showing significantly more obsessive-compulsive (OC) symptoms and lower degrees of insight regarding appearance concerns. Significantly more adolescents and young adults with vs. without self-reported BDD (36.4% vs. 8.8%) reported appearance-related suicidal ideation. In conclusion, body dysmorphic symptoms are common in adolescents and young adults and are associated with high rates of comorbid symptoms and suicidal ideation. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Probing Electrode Heterogeneity Using Fourier-Transformed Alternating Current Voltammetry: Application to a Dual-Electrode Configuration.

PubMed

Tan, Sze-Yin; Unwin, Patrick R; Macpherson, Julie V; Zhang, Jie; Bond, Alan M

2017-03-07

Quantitative studies of electron transfer processes at electrode/electrolyte interfaces, originally developed for homogeneous liquid mercury or metallic electrodes, are difficult to adapt to the spatially heterogeneous nanostructured electrode materials that are now commonly used in modern electrochemistry. In this study, the impact of surface heterogeneity on Fourier-transformed alternating current voltammetry (FTACV) has been investigated theoretically under the simplest possible conditions where no overlap of diffusion layers occurs and where numerical simulations based on a 1D diffusion model are sufficient to describe the mass transport problem. Experimental data that meet these requirements can be obtained with the aqueous [Ru(NH 3 ) 6 ] 3+/2+ redox process at a dual-electrode system comprised of electrically coupled but well-separated glassy carbon (GC) and boron-doped diamond (BDD) electrodes. Simulated and experimental FTACV data obtained with this electrode configuration, and where distinctly different heterogeneous charge transfer rate constants (k 0 values) apply at the individual GC and BDD electrode surfaces, are in excellent agreement. Principally, because of the far greater dependence of the AC current magnitude on k 0 , it is straightforward with the FTACV method to resolve electrochemical heterogeneities that are ∼1-2 orders of magnitude apart, as applies in the [Ru(NH 3 ) 6 ] 3+/2+ dual-electrode configuration experiments, without prior knowledge of the individual kinetic parameters (k 0 1 and k 0 2 ) or the electrode size ratio (θ 1 :θ 2 ). In direct current voltammetry, a difference in k 0 of >3 orders of magnitude is required to make this distinction.

TEM characterization of nanodiamond thin films.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qin, L.-C.; Zhou, D.; Krauss, A. R.

The microstructure of thin films grown by microwave plasma-enhanced chemical vapor deposition (MPCVD) from fullerene C{sub 60} precursors has been characterized by scanning electron microscopy (SEM), selected-area electron diffraction (SAED), bright-field electron microscopy, high-resolution electron microscopy (HREM), and parallel electron energy loss spectroscopy (PEELS). The films are composed of nanosize crystallites of diamond, and no graphitic or amorphous phases were observed. The diamond crystallite size measured from lattice images shows that most grains range between 3-5 nm, reflecting a gamma distribution. SAED gave no evidence of either sp2-bonded glassy carbon or sp3-bonded diamondlike amorphous carbon. The sp2-bonded configuration found inmore » PEELS was attributed to grain boundary carbon atoms, which constitute 5-10% of the total. Occasionally observed larger diamond grains tend to be highly faulted.« less

Fabrication of microchannels in polycrystalline diamond using pre-fabricated Si substrates

NASA Astrophysics Data System (ADS)

Chandran, Maneesh; Elfimchev, Sergey; Michaelson, Shaul; Akhvlediani, Rozalia; Ternyak, Orna; Hoffman, Alon

2017-10-01

In this paper, we report on a simple, feasible method to fabricate microchannels in diamond. Polycrystalline diamond microchannels were produced by fabricating trenches in a Si wafer and subsequently depositing a thin layer of diamond onto this substrate using the hot filament vapor deposition technique. Fabrication of trenches in the Si substrate at different depths was carried out by standard photolithography, and the subsequent deposition of the diamond layer was performed by the hot filament chemical vapor deposition technique. The growth mechanism of diamond that leads to the formation of closed diamond microchannels is discussed in detail based on the Knudsen number and growth chemistry of diamond. Variations in the crystallite size, crystalline quality, and thickness of the diamond layer along the trench depths were systematically analyzed using cross-sectional scanning electron microscopy and Raman spectroscopy. Defect density and formation of non-diamond forms of carbon in the diamond layer were found to increase with the trench depth, which sets a limit of 5-45 μm trench depth (or an aspect ratio of 1-9) for the fabrication of diamond microchannels using this method under the present conditions.

Shadows of Beauty - Prevalence of Body Dysmorphic Concerns in Germany is Increasing: Data from Two Representative Samples from 2002 and 2013.

PubMed

Gieler, Tanja; Schmutzer, Gabriele; Braehler, Elmar; Schut, Christina; Peters, Eva; Kupfer, Jörg

2016-08-23

Body dysmorphic disorder (BDD) is a psychosomatic disease associated with reduced quality of life and suicidal ideations. Increasing attention to beauty and the development of beauty industries lead to the hypothesis that BDD is increasing. The aim of this study was to test this hypothesis in two representative samples of Germans, assessed in 2002 and 2013. In 2002, n = 2,066 and in 2013, n = 2,508 Germans were asked to fill in the Dysmorphic Concern Questionnaire (DCQ), which assesses dysmorphic concerns. Subclinical and clinical dysmorphic concerns increased from 2002 to 2013 (subclinical from 0.5% to 2.6%, OR = 5.16 (CI95% = 2.64; 10.06); clinical from 0.5% to 1.0%, OR = 2.20 (CI95% = 1.03; 4.73). Women reported more dysmorphic concerns than men, with rates of 0.7% subclinical and 0.8 clinical BDD in women and 0.3% subclinical and 0.1% clinical BDD in men in 2002. In 2013, 2.8% subclinical and 1.2% clinical BDD were found in women and 2.4% subclinical and 0.8% clinical BDD in men. Further studies should assess predictors for developing a BDD and evaluate factors determining the efficacy of disease-specific psychotherapeutic and psychotropic drug treatments.

Reduced striatal dopamine D2/3 receptor availability in Body Dysmorphic Disorder.

PubMed

Vulink, Nienke C; Planting, Robin S; Figee, Martijn; Booij, Jan; Denys, Damiaan

2016-02-01

Though the dopaminergic system is implicated in Obsessive Compulsive and Related Disorders (OCRD), the dopaminergic system has never been investigated in-vivo in Body Dysmorphic Disorder (BDD). In line with consistent findings of reduced striatal dopamine D2/3 receptor availability in Obsessive Compulsive Disorder (OCD), we hypothesized that the dopamine D2/3 receptor availability in the striatum will be lower in patients with BDD in comparison to healthy subjects. Striatal dopamine D2/3 receptor Binding Potential (BPND) was examined in 12 drug-free BDD patients and 12 control subjects pairwise matched by age, sex, and handedness using [(123)I]iodobenzamide Single Photon Emission Computed Tomography (SPECT; bolus/constant infusion technique). Regions of interest were the caudate nucleus and the putamen. BPND was calculated as the ratio of specific striatal to binding in the occipital cortex (representing nonspecific binding). Compared to controls, dopamine D2/3 receptor BPND was significantly lower in BDD, both in the putamen (p=0.017) and caudate nucleus (p=0.022). This study provides the first evidence of a disturbed dopaminergic system in BDD patients. Although previously BDD was classified as a separate disorder (somatoform disorder), our findings give pathophysiological support for the recent reclassification of BDD to the OCRD in DSM-5. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.

Screening for Body Dysmorphic Disorder in a Dermatology Outpatient Setting at a Tertiary Care Centre

PubMed Central

Thanveer, Fibin; Khunger, Niti

2016-01-01

Context: A distressing pre-occupation with an imagined or slight defect in appearance with a marked negative effect on the patient's life is the core symptom of body dysmorphic disorder (BDD). Aim: To screen the patients attending a dermatology clinic at a tertiary care centre for BDD using the BDD-dermatology version (DV) questionnaire. Settings and Design: This cross-sectional study enrolled 245 consecutive patients from the dermatology outpatients clinic. Methods: The demographic details were collected and the DV of BDD screening questionnaire was administered. A 5-point Likert scale was used for objective scoring of the stated concern and patients who scored ≥3 were excluded from the study. Statistical Analysis Used: The results were statistically analysed. Differences between the groups were investigated by Chi-square analysis for categorical variables, and Fisher exact test wherever required. Results: A total of 177 patients completed the study, and of these, eight patients screened positive for BDD. The rate of BDD in patients presenting with cosmetic complaints was 7.5% and in those with general dermatology, complaints were 2.1%, with no significant difference between the two groups (P = 0.156). Facial flaws (62.5%) were the most common concern followed by body asymmetry (25%). Conclusion: The rates of BDD found in this study are comparable but at a lower rate than that reported in literature data. PMID:27761090

Escalation from normal appearance related intrusive cognitions to clinical preoccupations in Body Dysmorphic Disorder: A cross-sectional study.

PubMed

Giraldo-O'Meara, Martha; Belloch, Amparo

2018-07-01

Current cognitive approaches to Body Dysmorphic Disorder (BDD) assume that appearance-related intrusive cognitions and their functional consequences characterize the disorder, in a similar way that obsessive intrusive thoughts characterize the Obsessive-Compulsive Disorder (OCD). This study explores whether normal but unwanted appearance-related intrusive thoughts (AITs), escalate to clinical AITs when they are dysfunctionally appraised and instigate counterproductive neutralizing strategies. From a sample of 344 non-clinical individuals who reported a highly upsetting AIT during the past three months two subgroups were extracted according to their high (n = 68) and low (n = 276) vulnerability to BDD. The subjects in the high-risk group obtained significantly higher scores on the frequency of the most disturbing AIT and its emotional impact, interference, and appraisals evaluated with the Appearance Intrusions Questionnaire (AIQ). Additionally, two subgroups of 15 subjects each, with high and low risk to BDD, were formed and their scores were compared to 10 patients with BDD. The AIT had a greater emotional negative impact and more severe consequences on individuals with BDD compared to individuals at high-risk of BDD, which in turn, reported worse consequences of the AIT than those at low-risk. These results empirically support the similarities between BDD and OCD regarding their functional and phenomenological characteristics. Copyright © 2018 Elsevier B.V. All rights reserved.

The Relationship between Body Dysmorphic Disorder Behaviors and the Acquired Capability for Suicide

ERIC Educational Resources Information Center

Witte, Tracy K.; Didie, Elizabeth R.; Menard, William; Phillips, Katharine A.

2012-01-01

In a sample of 200 individuals diagnosed with body dysmorphic disorder (BDD), we utilized the interpersonal-psychological theory for suicide as a framework to examine BDD behaviors that might be associated with suicide risk, insofar as they might increase the acquired capability for suicide. We predicted that physically painful BDD behaviors…

A Cognitive-Behavioral Treatment Approach for Body Dysmorphic Disorder

ERIC Educational Resources Information Center

Wilhelm, Sabine; Buhlmann, Ulrike; Hayward, Laura C.; Greenberg, Jennifer L.; Dimaite, Ruta

2010-01-01

Although body dysmorphic disorder (BDD) has been described in the literature for more than a century, there has been only a limited focus on the development of cognitive behavioral treatments for BDD. Our case report provides a detailed description of a course of cognitive behavioral treatment (CBT) for an individual with BDD. The patient was…

Prophylometric and SEM analyses of four different finishing methods

PubMed Central

CHIODERA, G.; CERUTTI, F.; CERUTTI, A.; PUTIGNANO, A.; MANGANI, F.

2013-01-01

Summary Adhesion is the pivot of the modern restorative dentistry. Inlays, onlays and veneers have become a valid alternative to the traditional prosthetic treatments even in the rehabilitation of extremely damaged teeth, allowing a consistent saving of sound tooth tissues. Composite resins and dental adhesive are continously investigated and improved, nevertheless the optimization of the tooth-adhesive interface has to be considered: in fact, the long-term stability of adhesion between tooth and composite material depends on the treatment of the amelo-dentinal surfaces. This study investigated the quality of the occlusal walls of a cavity prepared to receive an inlay and finished with four different systems: thin and extra-thin diamond coated burs, a 12-blades carbide burs and a diamond-coated tip driven by sonic instrument. Consequently, prophylometric and SEM analyses were performed on the samples. The average roughness values recorded by the prophylometer were expressed by the parameters Ra and RZ: there is a correspondence between the numeric values and the pictures of the SEM. The results show a better quality (low roughness values) of the surface treated with multi-blade burs, followed by the this and extra-thin diamond coated burs. The 25 micron diamond-coated tip of the sonic instrument obtains the roughest surface and a sensibly higher amount of smear layer than the other tested systems. PMID:23741601

Thermal conductivity of ultrathin nano-crystalline diamond films determined by Raman thermography assisted by silicon nanowires

NASA Astrophysics Data System (ADS)

Anaya, Julian; Rossi, Stefano; Alomari, Mohammed; Kohn, Erhard; Tóth, Lajos; Pécz, Béla; Kuball, Martin

2015-06-01

The thermal transport in polycrystalline diamond films near its nucleation region is still not well understood. Here, a steady-state technique to determine the thermal transport within the nano-crystalline diamond present at their nucleation site has been demonstrated. Taking advantage of silicon nanowires as surface temperature nano-sensors, and using Raman Thermography, the in-plane and cross-plane components of the thermal conductivity of ultra-thin diamond layers and their thermal barrier to the Si substrate were determined. Both components of the thermal conductivity of the nano-crystalline diamond were found to be well below the values of polycrystalline bulk diamond, with a cross-plane thermal conductivity larger than the in-plane thermal conductivity. Also a depth dependence of the lateral thermal conductivity through the diamond layer was determined. The results impact the design and integration of diamond for thermal management of AlGaN/GaN high power transistors and also show the usefulness of the nanowires as accurate nano-thermometers.

2D nanosheet molybdenum disulphide (MoS2) modified electrodes explored towards the hydrogen evolution reaction

NASA Astrophysics Data System (ADS)

Rowley-Neale, Samuel J.; Brownson, Dale A. C.; Smith, Graham C.; Sawtell, David A. G.; Kelly, Peter J.; Banks, Craig E.

2015-10-01

We explore the use of two-dimensional (2D) MoS2 nanosheets as an electrocatalyst for the Hydrogen Evolution Reaction (HER). Using four commonly employed commercially available carbon based electrode support materials, namely edge plane pyrolytic graphite (EPPG), glassy carbon (GC), boron-doped diamond (BDD) and screen-printed graphite electrodes (SPE), we critically evaluate the reported electrocatalytic performance of unmodified and MoS2 modified electrodes towards the HER. Surprisingly, current literature focuses almost exclusively on the use of GC as an underlying support electrode upon which HER materials are immobilised. 2D MoS2 nanosheet modified electrodes are found to exhibit a coverage dependant electrocatalytic effect towards the HER. Modification of the supporting electrode surface with an optimal mass of 2D MoS2 nanosheets results in a lowering of the HER onset potential by ca. 0.33, 0.57, 0.29 and 0.31 V at EPPG, GC, SPE and BDD electrodes compared to their unmodified counterparts respectively. The lowering of the HER onset potential is associated with each supporting electrode's individual electron transfer kinetics/properties and is thus distinct. The effect of MoS2 coverage is also explored. We reveal that its ability to catalyse the HER is dependent on the mass deposited until a critical mass of 2D MoS2 nanosheets is achieved, after which its electrocatalytic benefits and/or surface stability curtail. The active surface site density and turn over frequency for the 2D MoS2 nanosheets is determined, characterised and found to be dependent on both the coverage of 2D MoS2 nanosheets and the underlying/supporting substrate. This work is essential for those designing, fabricating and consequently electrochemically testing 2D nanosheet materials for the HER.We explore the use of two-dimensional (2D) MoS2 nanosheets as an electrocatalyst for the Hydrogen Evolution Reaction (HER). Using four commonly employed commercially available carbon based electrode support materials, namely edge plane pyrolytic graphite (EPPG), glassy carbon (GC), boron-doped diamond (BDD) and screen-printed graphite electrodes (SPE), we critically evaluate the reported electrocatalytic performance of unmodified and MoS2 modified electrodes towards the HER. Surprisingly, current literature focuses almost exclusively on the use of GC as an underlying support electrode upon which HER materials are immobilised. 2D MoS2 nanosheet modified electrodes are found to exhibit a coverage dependant electrocatalytic effect towards the HER. Modification of the supporting electrode surface with an optimal mass of 2D MoS2 nanosheets results in a lowering of the HER onset potential by ca. 0.33, 0.57, 0.29 and 0.31 V at EPPG, GC, SPE and BDD electrodes compared to their unmodified counterparts respectively. The lowering of the HER onset potential is associated with each supporting electrode's individual electron transfer kinetics/properties and is thus distinct. The effect of MoS2 coverage is also explored. We reveal that its ability to catalyse the HER is dependent on the mass deposited until a critical mass of 2D MoS2 nanosheets is achieved, after which its electrocatalytic benefits and/or surface stability curtail. The active surface site density and turn over frequency for the 2D MoS2 nanosheets is determined, characterised and found to be dependent on both the coverage of 2D MoS2 nanosheets and the underlying/supporting substrate. This work is essential for those designing, fabricating and consequently electrochemically testing 2D nanosheet materials for the HER. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr05164a|ART

Delusional versus nondelusional body dysmorphic disorder: recommendations for DSM-5

PubMed Central

Phillips, Katharine A.; Hart, Ashley S.; Simpson, Helen Blair; Stein, Dan J.

2016-01-01

The core feature of body dysmorphic disorder (BDD) is distressing or impairing preoccupation with nonexistent or slight defects in one’s physical appearance. BDD beliefs are characterized by varying degrees of insight, ranging from good (ie, recognition that one’s BDD beliefs are not true) through “absent insight/delusional” beliefs (ie, complete conviction that one’s BDD beliefs are true). The Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., rev. (DSM-III-R) and The Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV) classified BDD’s nondelusional form in the somatoform section of the manual and its delusional form in the psychosis section, as a type of delusional disorder, somatic type (although DSM-IV allowed double-coding of delusional BDD as both a psychotic disorder and BDD). However, little or no evidence on this issue was available when these editions were published. In this article, we review the classification of BDD’s delusional and nondelusional variants in earlier editions of DSM and the limitations of their approaches. We then review empirical evidence on this topic, which has become available since DSM-IV was developed. Available evidence indicates that across a range of validators, BDD’s delusional and nondelusional variants have many more similarities than differences, including response to pharmacotherapy. Based on these data, we propose that BDD’s delusional and nondelusional forms be classified as the same disorder and that BDD’s diagnostic criteria include an insight specifier that spans a range of insight, including absent insight/delusional BDD beliefs. We hope that this recommendation will improve care for patients with this common and often-severe disorder. This increased understanding of BDD may also have implications for other disorders that have an “absent insight/delusional” form. PMID:23659348

Prevalence and heritability of body dysmorphic symptoms in adolescents and young adults: a population-based nationwide twin study.

PubMed

Enander, Jesper; Ivanov, Volen Z; Mataix-Cols, David; Kuja-Halkola, Ralf; Ljótsson, Brjánn; Lundström, Sebastian; Pérez-Vigil, Ana; Monzani, Benedetta; Lichtenstein, Paul; Rück, Christian

2018-02-28

Body dysmorphic disorder (BDD) usually begins during adolescence but little is known about the prevalence, etiology, and patterns of comorbidity in this age group. We investigated the prevalence of BDD symptoms in adolescents and young adults. We also report on the relative importance of genetic and environmental influences on BDD symptoms, and the risk for co-existing psychopathology. Prevalence of BDD symptoms was determined by a validated cut-off on the Dysmorphic Concerns Questionnaire (DCQ) in three population-based twin cohorts at ages 15 (n = 6968), 18 (n = 3738), and 20-28 (n = 4671). Heritability analysis was performed using univariate model-fitting for the DCQ. The risk for co-existing psychopathology was expressed as odds ratios (OR). The prevalence of clinically significant BDD symptoms was estimated to be between 1 and 2% in the different cohorts, with a significantly higher prevalence in females (1.3-3.3%) than in males (0.2-0.6%). The heritability of body dysmorphic concerns was estimated to be 49% (95% CI 38-54%) at age 15, 39% (95% CI 30-46) at age 18, and 37% (95% CI 29-42) at ages 20-28, with the remaining variance being due to non-shared environment. ORs for co-existing neuropsychiatric and alcohol-related problems ranged from 2.3 to 13.2. Clinically significant BDD symptoms are relatively common in adolescence and young adulthood, particularly in females. The low occurrence of BDD symptoms in adolescent boys may indicate sex differences in age of onset and/or etiological mechanisms. BDD symptoms are moderately heritable in young people and associated with an increased risk for co-existing neuropsychiatric and alcohol-related problems.

The presence, predictive utility, and clinical significance of body dysmorphic symptoms in women with eating disorders

PubMed Central

2013-01-01

Background Both eating disorders (EDs) and body dysmorphic disorder (BDD) are disorders of body image. This study aimed to assess the presence, predictive utility, and impact of clinical features commonly associated with BDD in women with EDs. Methods Participants recruited from two non-clinical cohorts of women, symptomatic and asymptomatic of EDs, completed a survey on ED (EDE-Q) and BDD (BDDE-SR) psychopathology, psychological distress (K-10), and quality of life (SF-12). Results A strong correlation was observed between the total BDDE-SR and the global EDE-Q scores (r = 0.79, p < 0.001). Multivariate analyses demonstrated that participants with probable EDs (n = 61) and BDD (n = 23) scored higher on 28 of the 30 BDDE-SR items compared to healthy controls (n = 173; all p < 0.05), indicating greater severity of BDD symptoms. BDD participants also scored higher than ED participants on 15 of the 30 BDDE-SR items (all p < 0.05). The remaining 15 items that ED and BDD participants scored similarly on (all p > 0.05) measured appearance checking, reassurance-seeking, camouflaging, comparison-making, and social avoidance. In addition to these behaviors, inspection of sensitivity (Se) and specificity (Sp) revealed that BDDE-SR items measuring preoccupation and dissatisfaction with appearance were most predictive of ED cases (Se and Sp > 0.60). Higher total BDDE-SR scores were associated with greater distress on the K-10 and poorer quality of life on the SF-12 (all p < 0.01). Conclusions Clinical features central to the model of BDD are common in, predictive of, and associated with impairment in women with EDs. Practice implications are that these features be included in the assessment and treatment of EDs. PMID:24999401

Donor Preconditioning After the Onset of Brain Death With Dopamine Derivate n-Octanoyl Dopamine Improves Early Posttransplant Graft Function in the Rat.

PubMed

Li, S; Korkmaz-Icöz, S; Radovits, T; Ruppert, M; Spindler, R; Loganathan, S; Hegedűs, P; Brlecic, P; Theisinger, B; Theisinger, S; Höger, S; Brune, M; Lasitschka, F; Karck, M; Yard, B; Szabó, G

2017-07-01

Heart transplantation is the therapy of choice for end-stage heart failure. However, hemodynamic instability, which has been demonstrated in brain-dead donors (BDD), could also affect the posttransplant graft function. We tested the hypothesis that treatment of the BDD with the dopamine derivate n-octanoyl-dopamine (NOD) improves donor cardiac and graft function after transplantation. Donor rats were given a continuous intravenous infusion of either NOD (0.882 mg/kg/h, BDD+NOD, n = 6) or a physiological saline vehicle (BDD, n = 9) for 5 h after the induction of brain death by inflation of a subdural balloon catheter. Controls were sham-operated (n = 9). In BDD, decreased left-ventricular contractility (ejection fraction; maximum rate of rise of left-ventricular pressure; preload recruitable stroke work), relaxation (maximum rate of fall of left-ventricular pressure; Tau), and increased end-diastolic stiffness were significantly improved after the NOD treatment. Following the transplantation, the NOD-treatment of BDD improved impaired systolic function and ventricular relaxation. Additionally, after transplantation increased interleukin-6, tumor necrosis factor TNF-α, NF-kappaB-p65, and nuclear factor (NF)-kappaB-p105 gene expression, and increased caspase-3, TNF-α and NF-kappaB protein expression could be significantly downregulated by the NOD treatment compared to BDD. BDD postconditioning with NOD through downregulation of the pro-apoptotic factor caspase-3, pro-inflammatory cytokines, and NF-kappaB may protect the heart against the myocardial injuries associated with brain death and ischemia/reperfusion. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Body-related cognitions, affect and post-event processing in body dysmorphic disorder.

PubMed

Kollei, Ines; Martin, Alexandra

2014-03-01

Cognitive behavioural models postulate that individuals with BDD engage in negative appearance-related appraisals and affect. External representations of one's appearance are thought to activate a specific mode of processing characterized by increased self-focused attention and an activation of negative appraisals and affect. The present study used a think-aloud approach including an in vivo body exposure to examine body-related cognitions and affect in individuals with BDD (n = 30), as compared to individuals with major depression (n = 30) and healthy controls (n = 30). Participants were instructed to think aloud during baseline, exposure and follow-up trials. Individuals with BDD verbalized more body-related and more negative body-related cognitions during all trials and reported higher degrees of negative affect than both control groups. A weaker increase of positive body-related cognitions during exposure, a stronger increase of sadness and anger after exposure and higher levels of post-event processing, were specific processes in individuals with BDD. Individuals with major depression were not excluded from the BDD group. This is associated with a reduction of internal validity, as the two clinical groups are somewhat interwoven. Key findings need to be replicated. The findings indicate that outcomes such as negative appearance-related cognitions and affect are specific to individuals with BDD. An external representation of one's appearance activates a specific mode of processing in BDD, manifesting itself in the absence of positive body-related cognitions, increased anger and sadness, and high levels of post-event processing. These specific processes may contribute toward maintenance of BDD psychopathology. Copyright © 2013 Elsevier Ltd. All rights reserved.

Method for the preparation of nanocrystalline diamond thin films

DOEpatents

Gruen, D.M.; Krauss, A.R.

1998-06-30

A method and system are disclosed for manufacturing nanocrystalline diamond film on a substrate such as field emission tips. The method involves forming a carbonaceous vapor, providing a gas stream of argon, hydrocarbon and possibly hydrogen, and combining the gas with the carbonaceous vapor, passing the combined carbonaceous vapor and gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the carbonaceous vapor and deposition of a diamond film on the field emission tip. 40 figs.

Depth profiling of nitrogen within 15N-incorporated nano-crystalline diamond thin films

NASA Astrophysics Data System (ADS)

Garratt, E.; AlFaify, S.; Cassidy, D. P.; Dissanayake, A.; Mancini, D. C.; Ghantasala, M. K.; Kayani, A.

2013-09-01

Nano-Crystalline Diamond (NCD) thin films are a topic of recent interest due to their excellent mechanical and electrical properties. The inclusion of nitrogen is a specific interest as its presence within NCD modifies its conductive properties. The methodology adopted for the characterization of nitrogen incorporated NCD films grown on a chromium underlayer determined a correlation between the chromium and nitrogen concentrations as well as a variation in the concentration profile of elements. Additionally, the concentration of nitrogen was found to be more than three times greater for these films versus those grown on a silicon substrate.

A critical review of cosmetic treatment outcomes in body dysmorphic disorder.

PubMed

Bowyer, Laura; Krebs, Georgina; Mataix-Cols, David; Veale, David; Monzani, Benedetta

2016-12-01

A high proportion of individuals with body dysmorphic disorder (BDD) undergo cosmetic treatments in an attempt to 'fix' perceived defect/s in their physical appearance. Despite the frequency with which such procedures are sought, few studies have prospectively examined the outcomes of cosmetic procedures in individuals with BDD. This article aims to critically review the literature and discuss the current debate that exists on outcomes of cosmetic treatment for individuals with BDD. An emerging literature suggests the majority of individuals with BDD have poor outcomes after cosmetic interventions; however, based on the current literature, it cannot be fully ruled out that certain individuals with mild BDD and localised appearance concerns may benefit from these interventions. Gaps in the current literature are highlighted, alongside recommendations for future research. Carefully conducted longitudinal studies with well-characterised patient populations are needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development and Validation of the Body-Focused Shame and Guilt Scale

PubMed Central

Weingarden, Hilary; Renshaw, Keith D.; Tangney, June P.; Wilhelm, Sabine

2015-01-01

Body shame is described as central in clinical literature on body dysmorphic disorder (BDD). However, empirical investigations of body shame within BDD are rare. One potential reason for the scarcity of such research may be that existing measures of body shame focus on eating and weight-based content. Within BDD, however, body shame likely focuses more broadly on shame felt in response to perceived appearance flaws in one’s body parts. We describe the development and validation of the Body-Focused Shame and Guilt Scale (BF-SGS), a measure of BDD-relevant body shame, across two studies: a two time-point study of undergraduates, and a follow-up study in two Internet-recruited clinical samples (BDD, obsessive compulsive disorder) and healthy controls. Across both studies, the BF-SGS shame subscale demonstrated strong reliability and construct validity, with Study 2 providing initial clinical norms. PMID:26640760

Social-evaluative versus self-evaluative appearance concerns in Body Dysmorphic Disorder.

PubMed

Anson, Martin; Veale, David; de Silva, Padmal

2012-12-01

Body Dysmorphic Disorder (BDD) is characterised by significant preoccupation and distress relating to an imagined or slight defect in appearance. Individuals with BDD frequently report marked concerns relating to perceived negative evaluation of their appearance by others, but research specifically investigating such concerns remains limited. This study investigated the extent and nature of appearance-related social-evaluative and self-evaluative concerns in individuals with BDD and healthy controls. BDD participants, in comparison to controls, reported high levels of importance and anxiety associated with perceptions of others' views of their appearance, in addition to their own view. No differences were observed in the level of importance and anxiety associated with their self-view in comparison to others' views. These findings support existing evidence indicating that appearance-related social-evaluative concerns are a central feature of BDD. Cognitive-behavioural treatment implications are discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Selective attention to imagined facial ugliness is specific to body dysmorphic disorder.

PubMed

Grocholewski, Anja; Kliem, Sören; Heinrichs, Nina

2012-03-01

Cognitive-behavioral models postulate that biases in selective attention are key factors contributing to susceptibility to and maintenance of body dysmorphic disorder (BDD). Visual attention in particular toward the imagined defect in appearance may be a crucial element. The present study therefore examined whether individuals with BDD showed increased visual attention to flaws in their own and in unfamiliar faces. Twenty individuals with BDD, 20 individuals with social phobia, and 20 mentally healthy individuals participated in an eye-tracking experiment. Participants were instructed to gaze at the photographs of 15 pictures of themselves and several unfamiliar faces. Only patients with BDD showed heightened selective visual attention to the imagined defect in their own face, as well to corresponding regions in other, unfamiliar faces. The results support the assumption that there is a specific attentional bias in BDD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Clinical features of body dysmorphic disorder in adolescents and adults

PubMed Central

Phillips, Katharine A.; Didie, Elizabeth R.; Menard, William; Pagano, Maria E.; Fay, Christina; Weisberg, Risa B.

2006-01-01

Body dysmorphic disorder (BDD) usually begins during adolescence, but its clinical features have received little investigation in this age group. Two hundred individuals with BDD (36 adolescents; 164 adults) completed interviewer-administered and self-report measures. Adolescents were preoccupied with numerous aspects of their appearance, most often their skin, hair, and stomach. Among the adolescents, 94.3% reported moderate, severe, or extreme distress due to BDD, 80.6% had a history of suicidal ideation, and 44.4% had attempted suicide. Adolescents experienced high rates and levels of impairment in school, work, and other aspects of psychosocial functioning. Adolescents and adults were comparable on most variables, although adolescents had significantly more delusional BDD beliefs and a higher lifetime rate of suicide attempts. Thus, adolescents with BDD have high levels of distress and rates of functional impairment, suicidal ideation, and suicide attempts. BDD’s clinical features in adolescents appear largely similar to those in adults. PMID:16499973

Electrostatic Self-Assembly of Diamond Nanoparticles onto Al- and N-Polar Sputtered Aluminum Nitride Surfaces.

PubMed

Yoshikawa, Taro; Reusch, Markus; Zuerbig, Verena; Cimalla, Volker; Lee, Kee-Han; Kurzyp, Magdalena; Arnault, Jean-Charles; Nebel, Christoph E; Ambacher, Oliver; Lebedev, Vadim

2016-11-17

Electrostatic self-assembly of diamond nanoparticles (DNPs) onto substrate surfaces (so-called nanodiamond seeding) is a notable technique, enabling chemical vapor deposition (CVD) of nanocrystalline diamond thin films on non-diamond substrates. In this study, we examine this technique onto differently polarized (either Al- or N-polar) c -axis oriented sputtered aluminum nitride (AlN) film surfaces. This investigation shows that Al-polar films, as compared to N-polar ones, obtain DNPs with higher density and more homogeneously on their surfaces. The origin of these differences in density and homogeneity is discussed based on the hydrolysis behavior of AlN surfaces in aqueous suspensions.

Body dysmorphic disorder.

PubMed

Fang, Angela; Matheny, Natalie L; Wilhelm, Sabine

2014-09-01

Body dysmorphic disorder (BDD) can be a severe and often debilitating psychiatric disorder that has been largely under-recognized and underdiagnosed. Pharmacologic and nonpharmacologic treatment options are available but limited. This review aims to provide an updated overview of the psychopathology and epidemiology of BDD, with an emphasis on current pharmacologic and nonpharmacologic treatment options for BDD. Copyright © 2014 Elsevier Inc. All rights reserved.

Relative relationships of general shame and body shame with body dysmorphic phenomenology and psychosocial outcomes.

PubMed

Weingarden, Hilary; Renshaw, Keith D; Davidson, Eliza; Wilhelm, Sabine

2017-07-01

Body Dysmorphic Disorder (BDD) is characterized by a preoccupation with a perceived flaw in appearance and repetitive avoidance behaviors. BDD involves severe psychosocial outcomes (e.g., depression, suicidality, functional impairment). Identifying correlates of BDD symptoms and outcomes can inform treatment. Shame, a painful emotion felt in response to critical self-judgment, may be one key correlate. However, research on shame in BDD is scarce and previous studies have not distinguished general shame from body shame. This study examines the relative relationships between body shame and general shame with body dysmorphic phenomenology and psychosocial outcomes. Participants ( N = 184) were recruited online via BDD organizations and completed a survey. Path analysis was used to examine associations between body and general shame with 1) body dysmorphic phenomenology and 2) depression severity, suicide risk, and functional impairment. Both types of shame were differentially related to outcomes. Body shame was more strongly related to phenomenology, whereas general shame was more strongly related to psychosocial outcomes. Thus, it may be important for BDD treatment to focus on reducing both general and body shame. Further research should evaluate whether current treatments adequately address and reduce general and body shame, and whether addressing shame promotes better treatment outcomes.

Imagery Rescripting for Body Dysmorphic Disorder: A Multiple-Baseline Single-Case Experimental Design.

PubMed

Willson, Rob; Veale, David; Freeston, Mark

2016-03-01

Individuals with body dysmorphic disorder (BDD) often experience negative distorted images of their appearance, and research suggests these may be linked to memories of adverse events such as bullying or teasing. This study evaluates imagery rescripting (ImR) as an intervention for BDD. In this article, we present a multiple-baseline single-case experimental design testing imagery rescripting as a brief, stand-alone intervention, with six individuals with BDD that related to aversive memories. The impact of the intervention was assessed by self-reported daily measures of symptom severity (preoccupation with appearance, appearance-related checking behaviors, appearance-related distress, and strength of belief that their main problem is their appearance) and standardized clinician ratings of BDD severity (Yale-Brown Obsessive Compulsive Scale modified for BDD). Four out of six of the participants responded positively to the intervention, with clinically meaningful improvement in symptomatology. Overall response was rapid; improvements began within the first week post-ImR intervention. From a small sample it is cautiously concluded that imagery rescripting may show promise as a module in cognitive-behavioral therapy for BDD, and is worthy of further investigation. Copyright © 2015. Published by Elsevier Ltd.

Prevalence, demographic and clinical characteristics of body dysmorphic disorder among psychiatric outpatients with mood, anxiety or somatoform disorders.

PubMed

van der Meer, Job; van Rood, Yanda R; van der Wee, Nic J; den Hollander-Gijsman, Margien; van Noorden, Martijn S; Giltay, Erik J; Zitman, Frans G

2012-09-01

To describe the prevalence, demographic and clinical characteristics of body dysmorphic disorder (BDD) compared with other psychiatric outpatients with a mood, anxiety or somatoform disorder. Outpatients referred for treatment of a mood, anxiety or somatoform disorder were routinely assessed at intake. A structured interview (MINI-Plus), observer-based and self-rating instruments were administered by an independent assessor. Among our sample of 3798 referred patients, 2947 patients were diagnosed with at least one DSM-IV mood, anxiety or somatoform disorder. Of these patients 1.8% (n = 54) met the diagnostic criteria for BDD. In comparison with other outpatients, patients with BDD were on average younger, less often married and were more often living alone. Highly prevalent comorbid diagnoses were major depression (in 46.3% of cases), social anxiety disorder (in 35.2% of cases) and obsessive-compulsive disorder (OCD) (in 16.7% of cases). Furthermore, patients with BDD had higher scores on the Clinical Global Impression of Severity (CGI-S) as well as lower scores on the Short Form 36 social role functioning. BDD is frequently associated with depression, social phobia and OCD. Patients with BDD have more distress and more impaired interpersonal functioning.

Low-loss lateral-extensional piezoelectric filters on ultrananocrystalline diamond.

PubMed

Fatemi, Hediyeh; Abdolvand, Reza

2013-09-01

In this work, lateral-extensional thin-film piezoelectric- on-diamond (TPoD) filters with very low insertion loss (IL) values (<4 dB) are reported. Two different lateral-extensional modes of a resonant structure are coupled together to realize a two-pole filter. The filters of this work exhibit low IL values, with fractional bandwidth between 0.08% and 0.2%, and have a very small footprint. This paper reports on the lowest IL in the literature for lateral-extensional thin-film piezoelectric filters with 50 Ω terminations in the GSM frequency band (~900 MHz). The narrow-band filters of this work are fabricated on three ultrananocrystalline diamond substrates to achieve higher frequencies without excessive reduction in the feature size. The paper also thoroughly studies the parameters that affect the performance of such filters and then discussions are evaluated by the statistical data collected from the fabricated wafers.

Formation of diamond nanoparticle thin films by electrophoretic deposition

NASA Astrophysics Data System (ADS)

Goto, Yosuke; Ohishi, Fujio; Tanaka, Kuniaki; Usui, Hiroaki

2016-03-01

Thin films of diamond nanoparticles were prepared by electrophoretic deposition (EPD) using 0.5 wt % dispersions in water, ethanol, and 2-propanol. The film growth rate increased with increasing voltage applied to the electrodes. However, an excessive increase in voltage caused the degradation of film morphology. The optimum voltage was 4 V with an electrode separation of 5 mm. The film growth rate was higher in organic solvents than in water. The deposited film had a smooth surface with an average surface roughness comparable to the size of primary particles of the source material. It is notable that the EPD films had a considerably higher physical stability than spin-coated and cast films. The stability was further improved by thermally annealing the films. IR analysis revealed that the diamond nanoparticles have carboxy and amino groups on their surfaces. It is considered that the stability of the EPD films originate from a chemical reaction between these functional groups.

Defect studies of thin ZnO films prepared by pulsed laser deposition

NASA Astrophysics Data System (ADS)

Vlček, M.; Čížek, J.; Procházka, I.; Novotný, M.; Bulíř, J.; Lančok, J.; Anwand, W.; Brauer, G.; Mosnier, J.-P.

2014-04-01

Thin ZnO films were grown by pulsed laser deposition on four different substrates: sapphire (0 0 0 1), MgO (1 0 0), fused silica and nanocrystalline synthetic diamond. Defect studies by slow positron implantation spectroscopy (SPIS) revealed significantly higher concentration of defects in the studied films when compared to a bulk ZnO single crystal. The concentration of defects in the films deposited on single crystal sapphire and MgO substrates is higher than in the films deposited on amorphous fused silica substrate and nanocrystalline synthetic diamond. Furthermore, the effect of deposition temperature on film quality was investigated in ZnO films deposited on synthetic diamond substrates. Defect studies performed by SPIS revealed that the concentration of defects firstly decreases with increasing deposition temperature, but at too high deposition temperatures it increases again. The lowest concentration of defects was found in the film deposited at 450° C.

Effect of diamond-like carbon thin film coated acrylic resin on candida albicans biofilm formation.

PubMed

Queiroz, José Renato Cavalcanti; Fissmer, Sara Fernanda; Koga-Ito, Cristiane Yumi; Salvia, Ana C R D; Massi, Marcos; Sobrinho, Argermiro Soares da Silva; Júnior, Lafayette Nogueira

2013-08-01

The purpose of this study was to evaluate the effect of diamond-like carbon thin films doped and undoped with silver nanoparticles coating poly(methyl methacrylate) (PMMA) on Candida albicans biofilm formation. The control of biofilm formation is important to prevent oral diseases in denture users. Forty-five PMMA disks were obtained, finished, cleaned in an ultrasonic bath, and divided into three groups: Gc, no surface coating (control group); Gdlc, coated with diamond-like carbon film; and Gag, coated with diamond-like carbon film doped with silver nanoparticles. The films were deposited using a reactive magnetron sputtering system (physical vapor deposition process). The specimens were characterized by optical profilometry, atomic force microscopy, and Rutherford backscattering spectroscopy analyses that determined differences in chemical composition and morphological structure. Following sterilization of the specimens by γ-ray irradiation, C. albicans (ATCC 18804) biofilms were formed by immersion in 2 ml of Sabouraud dextrose broth inoculated with a standardized fungal suspension. After 24 hours, the number of colony forming units (cfu) per specimen was counted. Data concerning biofilm formation were analyzed using ANOVA and the Tukey test (p < 0.05). C. albicans biofilm formation was significantly influenced by the films (p < 0.00001), reducing the number of cfu, while not affecting the roughness parameters (p > 0.05). The Tukey test showed no significant difference between Gdlc and Gag. Films deposited were extremely thin (∼50 nm). The silver particles presented a diameter between 60 and 120 nm and regular distribution throughout the film surface (to Gag). Diamond-like carbon films, doped or undoped with silver nanoparticles, coating the base of PMMA-based dentures could be an alternative procedure for preventing candidosis in denture users. © 2013 by the American College of Prosthodontists.

[Body dysmorphic disorder in cosmetic surgery - prevalence, psychiatric comorbidity and outcome].

PubMed

Hundscheid, T; van der Hulst, R R W J; Rutten, B P F; Leue, C

2014-01-01

Patients suffering from body dysmorphic disorder (bdd) are preoccupied with a slight or imagined defect in appearance. First of all, to review the literature on the prevalence of bdd in cosmetic surgery and thereafter to review the literature on psychiatric comorbidity and the outcome of surgical interventions. We based our search strategy on Embase, Medline and PubMed, using the search terms 'body dysmorphic disorder', 'cosmetic surgery', 'prevalence', 'comorbidity' and 'outcome'. Our search covered English and Dutch literature published after the introduction of bdd in dsm-iii-r and before 1 November, 2013. A study of the relevant articles enabled us to access additional articles mentioned in these texts. Our initial search strategy turned out to be too narrow. It was therefore broadened to include 'body dysmorphic disorder', 'cosmetic surgery', and 'prevalence'. Eventually we included 23 original articles. In 11 of these the prevalence of bdd varied from 3.2 to 53.6%. Twelve articles on psychiatric comorbidity revealed predominantly mood and anxiety disorders on axis I and cluster C personality disorders on axis II. Only two studies reported on the outcome of cosmetic surgery performed on bdd patients; surgical interventions, however, seemed to result in new preoccupations with the prolongation of psychiatric comorbidity. bdd is a common psychiatric disorder that can sometimes lead to cosmetic surgery. However, pre-operative screening of bdd patients is vital so that efficient psychiatric treatment can be initiated and patients are not subjected to surgical interventions which may be ineffective or even harmful.

Impairment in local and global processing and set-shifting in body dysmorphic disorder

PubMed Central

Kerwin, Lauren; Hovav, Sarit; Helleman, Gerhard; Feusner, Jamie D.

2014-01-01

Body dysmorphic disorder (BDD) is characterized by distressing and often debilitating preoccupations with misperceived defects in appearance. Research suggests that aberrant visual processing may contribute to these misperceptions. This study used two tasks to probe global and local visual processing as well as set shifting in individuals with BDD. Eighteen unmedicated individuals with BDD and 17 non-clinical controls completed two global-local tasks. The embedded figures task requires participants to determine which of three complex figures contained a simpler figure embedded within it. The Navon task utilizes incongruent stimuli comprised of a large letter (global level) made up of smaller letters (local level). The outcome measures were response time and accuracy rate. On the embedded figures task, BDD individuals were slower and less accurate than controls. On the Navon task, BDD individuals processed both global and local stimuli slower and less accurately than controls, and there was a further decrement in performance when shifting attention between the different levels of stimuli. Worse insight correlated with poorer performance on both tasks. Taken together, these results suggest abnormal global and local processing for non-appearance related stimuli among BDD individuals, in addition to evidence of poor set-shifting abilities. Moreover, these abnormalities appear to relate to the important clinical variable of poor insight. Further research is needed to explore these abnormalities and elucidate their possible role in the development and/or persistence of BDD symptoms. PMID:24972487

Large-area low-temperature ultrananocrystaline diamond (UNCD) films and integration with CMOS devices for monolithically integrated diamond MEMD/NEMS-CMOS systems.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sumant, A.V.; Auciello, O.; Yuan, H.-C

2009-05-01

Because of exceptional mechanical, chemical, and tribological properties, diamond has a great potential to be used as a material for the development of high-performance MEMS and NEMS such as resonators and switches compatible with harsh environments, which involve mechanical motion and intermittent contact. Integration of such MEMS/NEMS devices with complementary metal oxide semiconductor (CMOS) microelectronics will provide a unique platform for CMOS-driven commercial MEMS/NEMS. The main hurdle to achieve diamond-CMOS integration is the relatively high substrate temperatures (600-800 C) required for depositing conventional diamond thin films, which are well above the CMOS operating thermal budget (400 C). Additionally, a materialsmore » integration strategy has to be developed to enable diamond-CMOS integration. Ultrananocrystalline diamond (UNCD), a novel material developed in thin film form at Argonne, is currently the only microwave plasma chemical vapor deposition (MPCVD) grown diamond film that can be grown at 400 C, and still retain exceptional mechanical, chemical, and tribological properties comparable to that of single crystal diamond. We have developed a process based on MPCVD to synthesize UNCD films on up to 200 mm in diameter CMOS wafers, which will open new avenues for the fabrication of monolithically integrated CMOS-driven MEMS/NEMS based on UNCD. UNCD films were grown successfully on individual Si-based CMOS chips and on 200 mm CMOS wafers at 400 C in a MPCVD system, using Ar-rich/CH4 gas mixture. The CMOS devices on the wafers were characterized before and after UNCD deposition. All devices were performing to specifications with very small degradation after UNCD deposition and processing. A threshold voltage degradation in the range of 0.08-0.44V and transconductance degradation in the range of 1.5-9% were observed.« less

Investigation of the synergistic effects for p-nitrophenol mineralization by a combined process of ozonation and electrolysis using a boron-doped diamond anode.

PubMed

Qiu, Cuicui; Yuan, Shi; Li, Xiang; Wang, Huijiao; Bakheet, Belal; Komarneni, Sridhar; Wang, Yujue

2014-09-15

Electrolysis and ozonation are two commonly used technologies for treating wastewaters contaminated with nitrophenol pollutants. However, they are often handicapped by their slow kinetics and low yields of total organic carbon (TOC) mineralization. To improve TOC mineralization efficiency, we combined electrolysis using a boron-doped diamond (BDD) anode with ozonation (electrolysis-O3) to treat a p-nitrophenol (PNP) aqueous solution. Up to 91% TOC was removed after 60 min of the electrolysis-O3 process. In comparison, only 20 and 44% TOC was respectively removed by individual electrolysis and ozonation treatment conducted under similar reaction conditions. The result indicates that when electrolysis and ozonation are applied simultaneously, they have a significant synergy for PNP mineralization. This synergy can be mainly attributed to (i) the rapid degradation of PNP to carboxylic acids (e.g., oxalic acid and acetic acid) by O3, which would otherwise take a much longer time by electrolysis alone, and (ii) the effective mineralization of the ozone-refractory carboxylic acids to CO2 by OH generated from multiple sources in the electrolysis-O3 system. The result suggests that combining electrolysis with ozonation can provide a simple and effective way to mutually compensate the limitations of the two processes for degradation of phenolic pollutants. Copyright © 2014 Elsevier B.V. All rights reserved.

Photo-assisted electrochemical degradation of polychlorinated biphenyls with boron-doped diamond electrodes.

PubMed

Gutiérrez-Hernández, Rubén F; Bello-Mendoza, Ricardo; Hernández-Ramírez, Aracely; Malo, Edi A; Nájera-Aguilar, Hugo A

2017-09-19

The capacity of the photo electro-Fenton (PEF) process to degrade a mixture of seven polychlorinated biphenyl (PCB) congeners was studied. Boron-doped diamond (BDD) sheets were used as anode and cathode in the experimental electrolytic cell that contained Na 2 SO 4 0.05 M at pH 3 as supporting electrolyte for the electro generation of H 2 O 2 at the cathode. The effects of UV light intensity (254 and 365 nm), current density (8, 16 and 24 mA cm -2 ) and ferrous ion dosage (0.1, 0.2 and 0.3 mM) on PCB (C 0 = 50 μg L -1 ) degradation were evaluated. The highest level of PCB degradation (97%) was achieved with 16 mA cm -2 of current density, 0.1 mM of ferrous ion and UV light at 365 nm as irradiation source after 6 h of reaction. PCB28, PCB52 and PCB101 were not detected after 0.5, 1.5 and 3 h of reaction, respectively. The degradation of PCB138, PCB153, PCB180 and PCB209 was also high (>95%). The PEF system outperformed other oxidation processes (electro-Fenton, anodic oxidation, Fenton, photo-Fenton and UV photolysis) in terms of reaction rate and degradation efficiency. These results demonstrate for the first time the degradation of PCB209, the most highly chlorinated PCB congener, by an advanced electrochemical oxidation process.

Electrochemical disinfection using boron-doped diamond electrode--the synergetic effects of in situ ozone and free chlorine generation.

PubMed

Rajab, Mohamad; Heim, Carolin; Letzel, Thomas; Drewes, Jörg E; Helmreich, Brigitte

2015-02-01

This work investigated the capability of using a boron-doped diamond (BDD) electrode for bacterial disinfection in different water matrices containing varying amounts of chloride. The feed water containing Pseudomonas aeruginosa was electrochemically treated while applying different electrode conditions. Depending on the applied current density and the exposure time, inactivation between 4- and 8-log of the targeted microorganisms could be achieved. The disinfection efficiency was driven by the generation of free chlorine as a function of chloride concentration in the water. A synergetic effect of generating both free chlorine and ozone in situ during the disinfection process resulted in an effective bactericidal impact. The formation of the undesired by-products chlorate and perchlorate depended on the water matrix, the applied current density and the desired target disinfection level. In case of synthetic water with a low chloride concentration (20 mg L(-1)) and an applied current density of 167 mA cm(-2), a 6-log inactivation of Pseudomonas aeruginosa could be achieved after 5 min of exposure. The overall energy consumption ranged between 0.3 and 0.6 kW h m(-3) depending on the applied current density and water chemistry. Electrochemical water disinfection represents a suitable and efficient process for producing pathogen-free water without the use of any chemicals. Copyright © 2014 Elsevier Ltd. All rights reserved.

Electro-fenton and photoelectro-fenton degradation of sulfanilic acid using a boron-doped diamond anode and an air diffusion cathode.

PubMed

El-Ghenymy, Abdellatif; Garrido, José Antonio; Centellas, Francesc; Arias, Conchita; Cabot, Pere Lluís; Rodríguez, Rosa María; Brillas, Enric

2012-04-05

The mineralization of sulfanilic acid has been studied by electro-Fenton (EF) and photoelectro-Fenton (PEF) reaction with UVA light using an undivided electrochemical cell with a boron-doped diamond (BDD) anode and an air diffusion cathode able to generate H(2)O(2). Organics were then oxidized by hydroxyl radicals formed at the anode surface from water oxidation and in the bulk from Fenton's reaction between generated H(2)O(2) and added Fe(2+). The UVA irradiation in PEF enhanced the production of hydroxyl radicals in the bulk, accelerating the removal of organics and photodecomposed intermediates like Fe(III)-carboxylate complexes. Partial decontamination of 1.39 mM sulfanilic acid solutions was achieved by EF until 100 mA cm(-2) at optimum conditions of 0.4 mM Fe(2+) and pH 3.0. The increase in current density and substrate content led to an almost total mineralization. In contrast, the PEF process was more powerful, yielding almost complete mineralization in less electrolysis time under comparable conditions. The kinetics for sulfanilic acid decay always followed a pseudo-first-order reaction. Hydroquinone and p-benzoquinone were detected as aromatic intermediates, whereas acetic, maleic, formic, oxalic, and oxamic acids were identified as generated carboxylic acids. NH(4)(+) ion was preferentially released in both treatments, along with NO(3)(-) ion in smaller proportion.

Size dependence of nanoscale wear of silicon carbide

Treesearch

Chaiyapat Tangpatjaroen; David Grierson; Steve Shannon; Joseph E. Jakes; Izabela Szlufarska

2017-01-01

Nanoscale, single-asperity wear of single-crystal silicon carbide (sc- SiC) and nanocrystalline silicon carbide (nc-SiC) is investigated using single-crystal diamond nanoindenter tips and nanocrystalline diamond atomic force microscopy (AFM) tips under dry conditions, and the wear behavior is compared to that of single-crystal silicon with both thin and thick native...

Theoretical studies on a TeO2/ZnO/diamond-layered structure for zero TCD SAW devices

NASA Astrophysics Data System (ADS)

Dewan, Namrata; Sreenivas, K.; Gupta, Vinay

2008-08-01

High-frequency surface acoustic wave (SAW) devices based on diamond substrate are useful because of their very high SAW velocity. In the present work, SAW propagation characteristics, such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of a TeO2/ZnO/diamond-layered structure, are examined using theoretical calculations. The ZnO/diamond bi-layer structure is found to exhibit a high positive TCD value. A zero TCD device structure is obtained after integration with a TeO2 over layer having a negative TCD value. Introduction of a non-piezoelectric TeO2 over layer on the bi-layer structure (ZnO/diamond) increases the coupling coefficient. A relatively low thickness of TeO2 thin film (~(1.6-3.1) × 10-3λ) is required to achieve temperature-stable SAW devices based on diamond.

LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Measurement of optical absorption in polycrystalline CVD diamond plates by the phase photothermal method at a wavelength of 10.6 μm

NASA Astrophysics Data System (ADS)

Luk'yanov, A. Yu; Ral'chenko, Viktor G.; Khomich, A. V.; Serdtsev, E. V.; Volkov, P. V.; Savel'ev, A. V.; Konov, Vitalii I.

2008-12-01

A highly-efficient phase photothermal method is developed for quantitative measurements of the small optical absorption coefficient in thin plates made of highly transparent materials in which bulk losses significantly exceed surface losses. The bulk absorption coefficient at 10.6 μm is estimated in polycrystalline diamond plates grown from the vapour phase (a CVD diamond). The results are compared with those for natural and synthetic diamond single crystals and with the concentrations of nitrogen and hydrogen impurities. The absorption coefficient of the best samples of the CVD diamond did not exceed 0.06 cm-1, which, taking into account the high thermal conductivity of the CVD diamond (1800-2200 W mK-1 at room temperature), makes this material attractive for fabricating output windows of high-power CO2 lasers, especially for manufacturing large-size optics.

Amorphous-diamond electron emitter

DOEpatents

Falabella, Steven

2001-01-01

An electron emitter comprising a textured silicon wafer overcoated with a thin (200 .ANG.) layer of nitrogen-doped, amorphous-diamond (a:D-N), which lowers the field below 20 volts/micrometer have been demonstrated using this emitter compared to uncoated or diamond coated emitters wherein the emission is at fields of nearly 60 volts/micrometer. The silicon/nitrogen-doped, amorphous-diamond (Si/a:D-N) emitter may be produced by overcoating a textured silicon wafer with amorphous-diamond (a:D) in a nitrogen atmosphere using a filtered cathodic-arc system. The enhanced performance of the Si/a:D-N emitter lowers the voltages required to the point where field-emission displays are practical. Thus, this emitter can be used, for example, in flat-panel emission displays (FEDs), and cold-cathode vacuum electronics.

Randomised controlled trials of psychological & pharmacological treatments for body dysmorphic disorder: A systematic review.

PubMed

Phillipou, Andrea; Rossell, Susan L; Wilding, Helen E; Castle, David J

2016-11-30

Treatment for body dysmorphic disorder (BDD) often involves a combination of psychological and pharmacological interventions. However, only a small number of randomised controlled trials (RCTs) have been undertaken examining the efficacy of different therapeutic interventions. The aim of this study was to systematically review the RCTs involving psychological and pharmacological interventions for the treatment of BDD. The literature was searched to June 2015, and studies were included if they were written in English, empirical research papers published in peer-review journals, specifically assessed BDD patients, and involved a RCT assessing BDD symptoms pre- and post-intervention. Nine studies were identified: six involving psychological and three involving pharmacological interventions. Cognitive behaviour therapy, metacognitive therapy and selective serotonin reuptake inhibitors were identified as treatments with potential benefit. The small number of RCTs and the heterogeneity of findings emphasises the need for more high quality RCTs assessing both psychological and pharmacological interventions for BDD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Body image concern and selective attention to disgusting and non-self appearance-related stimuli.

PubMed

Onden-Lim, Melissa; Wu, Ray; Grisham, Jessica R

2012-09-01

Although selective attention to one's own appearance has been widely documented in studies of body dysmorphic disorder (BDD), little is known about attentional bias toward non-self appearance-related stimuli in BDD. Furthermore, despite reports of heightened experience of disgust in BDD, it is unknown whether these individuals differentially attend to disgusting stimuli and whether disgust is important in processing of unattractive stimuli. We used a dot probe procedure to investigate the relationship between dysmorphic concern, a defining feature of BDD, and selective attention to faces, attractive, unattractive and disgusting images in a female heterosexual student population (N=92). At the long stimulus presentation (1000 ms), dysmorphic concern was positively associated with attention to faces in general and attractive appearance-related images. In contrast, at the short stimulus presentation (200 ms), there was a positive association between dysmorphic concern and disgusting images. Implications for theoretical models of BDD are discussed. Copyright © 2012. Published by Elsevier Ltd.

Skin picking disorder with co-occurring body dysmorphic disorder.

PubMed

Grant, Jon E; Redden, Sarah A; Leppink, Eric W; Odlaug, Brian L

2015-09-01

There is clinical overlap between skin picking disorder (SPD) and body dysmorphic disorder (BDD), but little research has examined clinical and cognitive correlates of the two disorders when they co-occur. Of 55 participants with SPD recruited for a neurocognitive study and two pharmacological studies, 16 (29.1%) had co-occurring BDD. SPD participants with and without BDD were compared to each other and to 40 healthy volunteers on measures of symptom severity, social functioning, and cognitive assessments using the Stop-signal task (assessing response impulsivity) and the Intra-dimensional/Extra-dimensional Set Shift task (assessing cognitive flexibility). Individuals with SPD and BDD exhibited significantly worse picking, significantly worse overall psychosocial functioning, and significantly greater dysfunction on aspects of cognitive flexibility. These results indicate that when SPD co-occurs with BDD unique clinical and cognitive aspects of SPD may be more pronounced. Future work should explore possible subgroups in SPD and whether these predict different treatment outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Facial discrimination in body dysmorphic, obsessive-compulsive and social anxiety disorders.

PubMed

Hübner, Claudia; Wiesendahl, Wiebke; Kleinstäuber, Maria; Stangier, Ulrich; Kathmann, Norbert; Buhlmann, Ulrike

2016-02-28

Body dysmorphic disorder (BDD) is characterized by preoccupation with perceived flaws in one's own appearance. Several risk factors such as aesthetic perceptual sensitivity have been proposed to explain BDD's unique symptomatology. Although research on facial discrimination is limited so far, the few existing studies have produced mixed results. Thus, the purpose of this study was to further examine facial discrimination in BDD. We administered a facial discrimination paradigm, which allows to assess the ability to identify slight to strong facial changes (e.g., hair loss, acne) when presented with an original (unmodified) facial image, relative to a changed (modified) facial image. The experiment was administered in individuals with BDD, social anxiety disorder, obsessive-compulsive disorder, and mentally healthy controls (32 per group, respectively). Overall, groups did not differ with respect to their ability to correctly identify facial aberrations when presented with other people's faces. Our findings do not support the hypothesis of enhanced general aesthetic perceptual sensitivity in individuals with (vs. without) BDD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Thin CVD-diamond RF Pill-Box vacuum windows for LHCD systems

NASA Astrophysics Data System (ADS)

Ravera, G. L.; Ceccuzzi, S.; Cardinali, A.; Cesario, R.; Mirizzi, F.; Schettini, G.; Tuccillo, A. A.

2014-02-01

The preliminary assessment of a Lower Hybrid Current Drive (LHCD) system for the DEMOnstration power plant (DEMO) is mainly focused on the R&D needs of the less conventional RF components of the Main Transmission Line (MTL) and of the launcher. 500 kW, CW klystrons will be used to deliver the RF power to independent Passive Active Multijunction (PAM) launcher modules at 5 GHz. This paper describes the criteria followed to investigate the optimum solution for the RF window used as vacuum barrier between the MTL and the launcher, an open issue in the LHCD system for ITER too. The best candidate, capable of withstanding a power level of, or above, 0.5 MW in CW operation and to satisfy the electrical and thermonuclear requirements, is a Pill-Box assembly, based on a thin single disk of CVD-diamond as dielectric, water cooled at the edge. A thickness of 3 mm, much shorter than half a wavelength of the TE°11 mode in the dielectric as in the conventional window (unfeasible and too expensive with CVD-diamond at these frequencies), is sufficient to limit the exerted stress at the edge under the fracture stress for a maximum pressure applied of 0.9 MPa. In this paper the simulation results of conventional and thin CVD-diamond vacuum windows are presented comparing S-parameters, losses and electric fields in both matching condition and with VSWR = 2, using WR284 and WR229 as input/output rectangular waveguide.

Body dysmorphic disorder and orthodontics--an overview for clinicians.

PubMed

Anthony, Marshneil Trista; Farella, Mauro

2014-11-01

Patients with body dysmorphic disorder (BDD) often seek aesthetic medical treatment including orthodontics to correct their perceived physical defects. When the disorder pertains to the dentofacial region, it is important for orthodontists to be familiar with this condition. The purpose of this article is to provide an overview of the current knowledge on BDD and its relationship to orthodontics. PubMed, Scopus, Science Direct, and Google Scholar databases were searched for publications relating to BDD and orthodontics. Further articles were sourced from the reference lists of the articles identified through the search. The literature recommends that orthodontic patients suspected of having BDD should be referred to a psychiatrist for a definitive diagnosis and subsequent management. However, this may be difficult to implement in clinical practice. Management by a psychiatrist could include pharmacotherapy and cognitive behavioural therapy. There is still debate as to whether orthodontic treatment should be provided for these patients. As health care workers providing aesthetic treatment to patients, orthodontists should be aware of BDD and its implications. Risks include repeated requests for unnecessary treatment, dissatisfaction with the result and thus potential for litigation. BDD still remains a challenge to diagnose, and further research is needed to determine the appropriate management of orthodontic patients suffering from the disorder.

Cognitive dysfunction in Body Dysmorphic Disorder: New implications for nosological systems & neurobiological models

PubMed Central

Jefferies-Sewell, K; Chamberlain, SR; Fineberg, NA; Laws, KR

2017-01-01

Background Body dysmorphic disorder (BDD) is a debilitating disorder, characterised by obsessions and compulsions relating specifically to perceived appearance, newly classified within the DSM-5 Obsessive-Compulsive and Related Disorders grouping. Until now, little research has been conducted into the cognitive profile of this disorder. Materials and Methods Participants with BDD (n=12) and healthy controls (n=16) were tested using a computerised neurocognitive battery investigating attentional set-shifting (Intra/Extra Dimensional Set Shift Task), decision-making (Cambridge Gamble Task), motor response-inhibition (Stop-Signal Reaction Time Task) and affective processing (Affective Go-No Go Task). The groups were matched for age, IQ and education. Results In comparison to controls, patients with BDD showed significantly impaired attentional set shifting, abnormal decision-making, impaired response inhibition and greater omission and commission errors on the emotional processing task. Conclusions Despite the modest sample size, our results showed that individuals with BDD performed poorly compared to healthy controls on tests of cognitive flexibility, reward and motor impulsivity and affective processing. Results from separate studies in OCD patients suggest similar cognitive dysfunction. Therefore, these findings are consistent with the re-classification of BDD alongside OCD. These data also hint at additional areas of decision-making abnormalities that might contribute specifically to the psychopathology of BDD. PMID:27899165

Ion-Implanted Diamond Films and Their Tribological Properties

NASA Technical Reports Server (NTRS)

Wu, Richard L. C.; Miyoshi, Kazuhisa; Korenyi-Both, Andras L.; Garscadden, Alan; Barnes, Paul N.

1993-01-01

This paper reports the physical characterization and tribological evaluation of ion-implanted diamond films. Diamond films were produced by microwave plasma, chemical vapor deposition technique. Diamond films with various grain sizes (0.3 and 3 microns) and roughness (9.1 and 92.1 nm r.m.s. respectively) were implanted with C(+) (m/e = 12) at an ion energy of 160 eV and a fluence of 6.72 x 10(exp 17) ions/sq cm. Unidirectional sliding friction experiments were conducted in ultrahigh vacuum (6.6 x 10(exp -7)Pa), dry nitrogen and humid air (40% RH) environments. The effects of C(+) ion bombardment on fine and coarse-grained diamond films are as follows: the surface morphology of the diamond films did not change; the surface roughness increased (16.3 and 135.3 nm r.m.s.); the diamond structures were damaged and formed a thin layer of amorphous non-diamond carbon; the friction coefficients dramatically decreased in the ultrahigh vacuum (0.1 and 0.4); the friction coefficients decreased slightly in the dry nitrogen and humid air environments.

Electrostatic Self-Assembly of Diamond Nanoparticles onto Al- and N-Polar Sputtered Aluminum Nitride Surfaces

PubMed Central

Yoshikawa, Taro; Reusch, Markus; Zuerbig, Verena; Cimalla, Volker; Lee, Kee-Han; Kurzyp, Magdalena; Arnault, Jean-Charles; Nebel, Christoph E.; Ambacher, Oliver; Lebedev, Vadim

2016-01-01

Electrostatic self-assembly of diamond nanoparticles (DNPs) onto substrate surfaces (so-called nanodiamond seeding) is a notable technique, enabling chemical vapor deposition (CVD) of nanocrystalline diamond thin films on non-diamond substrates. In this study, we examine this technique onto differently polarized (either Al- or N-polar) c-axis oriented sputtered aluminum nitride (AlN) film surfaces. This investigation shows that Al-polar films, as compared to N-polar ones, obtain DNPs with higher density and more homogeneously on their surfaces. The origin of these differences in density and homogeneity is discussed based on the hydrolysis behavior of AlN surfaces in aqueous suspensions. PMID:28335345

The classification of body dysmorphic disorder symptoms in male and female adolescents.

PubMed

Schneider, Sophie C; Baillie, Andrew J; Mond, Jonathan; Turner, Cynthia M; Hudson, Jennifer L

2018-01-01

Body dysmorphic disorder (BDD) was categorised in DSM-5 within the newly created 'obsessive-compulsive and related disorders' chapter, however this classification remains subject to debate. Confirmatory factor analysis was used to test competing models of the co-occurrence of symptoms of BDD, obsessive-compulsive disorder, unipolar depression, anxiety, and eating disorders in a community sample of adolescents, and to explore potential sex differences in these models. Self-report questionnaires assessing disorder symptoms were completed by 3149 Australian adolescents. The fit of correlated factor models was calculated separately in males and females, and measurement invariance testing compared parameters of the best-fitting model between males and females. All theoretical models of the classification of BDD had poor fit to the data. Good fit was found for a novel model where BDD symptoms formed a distinct latent factor, correlated with affective disorder and eating disorder latent factors. Metric non-invariance was found between males and females, and the majority of factor loadings differed between males and females. Correlations between some latent factors also differed by sex. Only cross-sectional data were collected, and the study did not assess a broad range of DSM-5 defined eating disorder symptoms or other disorders in the DSM-5 obsessive-compulsive and related disorders chapter. This study is the first to statistically evaluate competing models of BDD classification. The findings highlight the unique features of BDD and its associations with affective and eating disorders. Future studies examining the classification of BDD should consider developmental and sex differences in their models. Copyright © 2017. Published by Elsevier B.V.

Visual processing in anorexia nervosa and body dysmorphic disorder: similarities, differences, and future research directions

PubMed Central

Madsen, Sarah K.; Bohon, Cara; Feusner, Jamie D.

2013-01-01

Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are psychiatric disorders that involve distortion of the experience of one’s physical appearance. In AN, individuals believe that they are overweight, perceive their body as “fat,” and are preoccupied with maintaining a low body weight. In BDD, individuals are preoccupied with misperceived defects in physical appearance, most often of the face. Distorted visual perception may contribute to these cardinal symptoms, and may be a common underlying phenotype. This review surveys the current literature on visual processing in AN and BDD, addressing lower- to higher-order stages of visual information processing and perception. We focus on peer-reviewed studies of AN and BDD that address ophthalmologic abnormalities, basic neural processing of visual input, integration of visual input with other systems, neuropsychological tests of visual processing, and representations of whole percepts (such as images of faces, bodies, and other objects). The literature suggests a pattern in both groups of over-attention to detail, reduced processing of global features, and a tendency to focus on symptom-specific details in their own images (body parts in AN, facial features in BDD), with cognitive strategy at least partially mediating the abnormalities. Visuospatial abnormalities were also evident when viewing images of others and for non-appearance related stimuli. Unfortunately no study has directly compared AN and BDD, and most studies were not designed to disentangle disease-related emotional responses from lower-order visual processing. We make recommendations for future studies to improve the understanding of visual processing abnormalities in AN and BDD. PMID:23810196

Visual selective attention in body dysmorphic disorder, bulimia nervosa and healthy controls.

PubMed

Kollei, Ines; Horndasch, Stefanie; Erim, Yesim; Martin, Alexandra

2017-01-01

Cognitive behavioral models postulate that selective attention plays an important role in the maintenance of body dysmorphic disorder (BDD). It is suggested that individuals with BDD overfocus on perceived defects in their appearance, which may contribute to the excessive preoccupation with their appearance. The present study used eye tracking to examine visual selective attention in individuals with BDD (n=19), as compared to individuals with bulimia nervosa (BN) (n=21) and healthy controls (HCs) (n=21). Participants completed interviews, questionnaires, rating scales and an eye tracking task: Eye movements were recorded while participants viewed photographs of their own face and attractive as well as unattractive other faces. Eye tracking data showed that BDD and BN participants focused less on their self-rated most attractive facial part than HCs. Scanning patterns in own and other faces showed that BDD and BN participants paid as much attention to attractive as to unattractive features in their own face, whereas they focused more on attractive features in attractive other faces. HCs paid more attention to attractive features in their own face and did the same in attractive other faces. Results indicate an attentional bias in BDD and BN participants manifesting itself in a neglect of positive features compared to HCs. Perceptual retraining may be an important aspect to focus on in therapy in order to overcome the neglect of positive facial aspects. Future research should aim to disentangle attentional processes in BDD by examining the time course of attentional processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Psychopathology symptoms in a sample of female cosmetic surgery patients.

PubMed

Mulkens, Sandra; Bos, Arjan E R; Uleman, Richard; Muris, Peter; Mayer, Birgit; Velthuis, Peter

2012-03-01

During the past decades, cosmetic surgery has become increasingly popular. People with certain psychopathology disorders, for example, body dysmorphic disorder (BDD), are dissatisfied with their physical appearance, and a significant number try to receive cosmetic medical treatment for their complaints. It seems relatively easy for them to receive this type of surgery, despite the fact that it has no or even adverse effects on the symptoms. The present study aimed to investigate the psychological condition and especially the presence of psychopathological symptoms such as BDD in cosmetic surgery patients. Questionnaires about body image dissatisfaction, symptoms of BDD and psychopathology in general and satisfaction about surgery were sent to patients who had been treated in a large cosmetic surgery clinic. Of the patients who replied, 86% were pleased with the outcome of the cosmetic procedure. Further, 21-59% of these former patients scored higher on questionnaires of body image dissatisfaction and psychopathological symptoms than a norm group from the general population. When differentiating the group on the basis of BDD symptomatology, it appeared that the high BDD symptomatic group displayed significantly worse outcome on all measurements. That is, high BDD symptomatic patients were more dissatisfied about the result of surgery, exhibited higher levels of psychopathology, and had lower self-esteem than the low symptomatic BDD patients. These findings clearly suggest that the evaluation of the psychological condition and motivation of the candidate patient might be a valuable addition to the standard procedure in cosmetic medical treatment settings. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Interlayer utilization (including metal borides) for subsequent deposition of NSD films via microwave plasma CVD on 316 and 440C stainless steels

NASA Astrophysics Data System (ADS)

Ballinger, Jared

Diamond thin films have promising applications in numerous fields due to the extreme properties of diamonds in conjunction with the surface enhancement of thin films. Biomedical applications are numerous including temporary implants and various dental and surgical instruments. The unique combination of properties offered by nanostructured diamond films that make it such an attractive surface coating include extreme hardness, low obtainable surface roughness, excellent thermal conductivity, and chemical inertness. Regrettably, numerous problems exist when attempting to coat stainless steel with diamond generating a readily delaminated film: outward diffusion of iron to the surface, inward diffusion of carbon limiting necessary surface carbon precursor, and the mismatch between the coefficients of thermal expansion yielding substantial residual stress. While some exotic methods have been attempted to overcome these hindrances, the most common approach is the use of an intermediate layer between the stainless steel substrate and the diamond thin film. In this research, both 316 stainless steel disks and 440C stainless steel ball bearings were tested with interlayers including discrete coatings and graded, diffusion-based surface enhancements. Titanium nitride and thermochemical diffusion boride interlayers were both examined for their effectiveness at allowing for the growth of continuous and adherent diamond films. Titanium nitride interlayers were deposited by cathodic arc vacuum deposition on 440C bearings. Lower temperature diamond processing resulted in improved surface coverage after cooling, but ultimately, both continuity and adhesion of the nanostructured diamond films were unacceptable. The ability to grow quality diamond films on TiN interlayers is in agreement with previous work on iron and low alloy steel substrates, and the similarly seen inadequate adhesion strength is partially a consequence of the lacking establishment of an interfacial carbide phase. Surface boriding was implemented using the novel method of microwave plasma CVD with a mixture of hydrogen and diborane gases. On 440C bearings, dual phase boride layers of Fe2B and FeB were formed which supported adhered nanostructured diamond films. Continuity of the films was not seamless with limited regions remaining uncoated potentially corresponding to delamination of the film as evidenced by the presence of tubular structures presumably composed of sp2 bonded carbon. Surface boriding of 316 stainless steel discs was conducted at various powers and pressures to achieve temperatures ranging from 550-800 °C. The substrate boriding temperature was found to substantially influence the resultant interlayer by altering the metal boride(s) present. The lowest temperatures produced an interlayer where CrB was the single detected phase, higher temperatures yielded the presence of only Fe2B, and a combination of the two phases resulted from an intermediate boriding temperature. Compared with the more common, commercialized boriding methods, this a profound result given the problems posed by the FeB phase in addition to other advantages offered by CVD processes and microwave generated plasmas in general. Indentation testing of the boride layers revealed excellent adhesion strength for all borided interlayers, and above all, no evidence of cracking was observed for a sole Fe2B phase. As with boriding of 440C bearings, subsequent diamond deposition was achieved on these interlayers with substantially improved adhesion strength relative to diamond coated TiN interlayers. Both XRD and Raman spectroscopy confirmed a nanostructured diamond film with interfacial chromium carbides responsible for enhanced adhesion strength. Interlayers consisting solely of Fe2B have displayed an ability to support fully continuous nanostructured diamond films, yet additional study is required for consistent reproduction. This is in good agreement with initial work on pack borided high alloy steels to promote diamond film surface modification. The future direction for continued research of nanostructured diamond coatings on microwave plasma CVD borided stainless steel should further investigate the adhesion of both borided interlayers and subsequent NSD films in addition to short, interrupted diamond depositions to study the interlayer/diamond film interface.

2D nanosheet molybdenum disulphide (MoS2) modified electrodes explored towards the hydrogen evolution reaction.

PubMed

Rowley-Neale, Samuel J; Brownson, Dale A C; Smith, Graham C; Sawtell, David A G; Kelly, Peter J; Banks, Craig E

2015-11-21

We explore the use of two-dimensional (2D) MoS2 nanosheets as an electrocatalyst for the Hydrogen Evolution Reaction (HER). Using four commonly employed commercially available carbon based electrode support materials, namely edge plane pyrolytic graphite (EPPG), glassy carbon (GC), boron-doped diamond (BDD) and screen-printed graphite electrodes (SPE), we critically evaluate the reported electrocatalytic performance of unmodified and MoS2 modified electrodes towards the HER. Surprisingly, current literature focuses almost exclusively on the use of GC as an underlying support electrode upon which HER materials are immobilised. 2D MoS2 nanosheet modified electrodes are found to exhibit a coverage dependant electrocatalytic effect towards the HER. Modification of the supporting electrode surface with an optimal mass of 2D MoS2 nanosheets results in a lowering of the HER onset potential by ca. 0.33, 0.57, 0.29 and 0.31 V at EPPG, GC, SPE and BDD electrodes compared to their unmodified counterparts respectively. The lowering of the HER onset potential is associated with each supporting electrode's individual electron transfer kinetics/properties and is thus distinct. The effect of MoS2 coverage is also explored. We reveal that its ability to catalyse the HER is dependent on the mass deposited until a critical mass of 2D MoS2 nanosheets is achieved, after which its electrocatalytic benefits and/or surface stability curtail. The active surface site density and turn over frequency for the 2D MoS2 nanosheets is determined, characterised and found to be dependent on both the coverage of 2D MoS2 nanosheets and the underlying/supporting substrate. This work is essential for those designing, fabricating and consequently electrochemically testing 2D nanosheet materials for the HER.

Ti:Pt:Au:Ni thin-film CVD diamond sensor ability for charged particle detection.

PubMed

Kasiwattanawut, Haruetai; Tchouaso, Modeste Tchakoua; Prelas, Mark A

2018-05-22

This work demonstrates the development of diamond sensors with reliable contacts using a new metallization formula, which can operate under high-pressure gas environment. The metallization was created using thin film layers of titanium, platinum, gold and nickel deposited on a single crystal electronic grade CVD diamond chip. The contacts were 2 mm in diameter with thickness of 50/5/20/150 nm of Ti:Pt:Au:Ni. The optimum operating voltage of the sensor was determined from the current-voltage measurements. The sensor was calibrated with 239 Pu and 241 Am alpha radiation sources at 300 V. The energy resolution of the Ti:Pt:Au:Ni diamond sensor was determined to be 7.6% at 5.2 MeV of 239 Pu and 2.2% at 5.48 MeV of 241 Am. The high-pressure gas loading environment under which this sensor was used is discussed. Specifically, experimental observations are described using hydrogen loading of nickel as a means of initiating low energy nuclear reactions. No neutrons, electrons, ions or other ionizing radiations were observed in these experiments. Copyright © 2018 Elsevier Ltd. All rights reserved.

A study for anticorrosion and tribological behaviors of thin/thick diamond-like carbon films in seawater

NASA Astrophysics Data System (ADS)

Ye, Yewei; Jia, Shujuan; Zhang, Dawei; Liu, Wei; Zhao, Haichao

2018-03-01

The thin and thick diamond-like carbon (DLC) films were prepared by unbalanced magnetron sputtering technique on 304L stainless steels and (100) silicon wafers. Microstructure, mechanical, corrosion and tribological properties were systematically investigated by SEM, Raman, nanoindenter, scratch tester, modulab electrochemical workstation and R-tec multifunctional tribological tester. Results showed that the adhesion force presented a descending trend with the growth in soaking time. The adhesion force of the thin DLC film with high residual compressive stress (‑3.72 GPa) was higher than that of the thick DLC film (‑2.96 GPa). During the corrosion test, the thick DLC film showed a higher impendence and a lower corrosion current density than the thin DLC film, which is attributed to the barrier action of large thickness. Compared to bare 304L substrate, the friction coefficients and wear rates of DLC films in seawater were obviously decreased. Meanwhile, the thin DLC film with ideal residual compressive stress, super adhesion force and good plastic deformation resistance revealed an excellent anti-wear ability in seawater.

Fabrication of Hydrogenated Diamond Metal-Insulator-Semiconductor Field-Effect Transistors.

PubMed

Liu, Jiangwei; Koide, Yasuo

2017-01-01

Diamond is regarded as a promising material for fabrication of high-power and high-frequency electronic devices due to its remarkable intrinsic properties, such as wide band gap energy, high carrier mobility, and high breakdown field. Meanwhile, since diamond has good biocompatibility, long-term durability, good chemical inertness, and a large electron-chemical potential window, it is a suitable candidate for the fabrication of biosensors. Here, we demonstrate the fabrication of hydrogenated diamond (H-diamond) based metal-insulator-semiconductor field-effect transistors (MISFETs). The fabrication is based on the combination of laser lithography, dry-etching, atomic layer deposition (ALD), sputtering deposition (SD), electrode evaporation, and lift-off techniques. The gate insulator is high-k HfO 2 with a SD/ALD bilayer structure. The thin ALD-HfO 2 film (4.0 nm) acts as a buffer layer to prevent the hydrogen surface of the H-diamond from plasma discharge damage during the SD-HfO 2 deposition. The growth of H-diamond epitaxial layer, fabrication of H-diamond MISFETs, and electrical property measurements for the MISFETs is demonstrated. This chapter explains the fabrication of H-diamond FET based biosensors.

Diamond MEMS: wafer scale processing, devices, and technology insertion

NASA Astrophysics Data System (ADS)

Carlisle, J. A.

2009-05-01

Diamond has long held the promise of revolutionary new devices: impervious chemical barriers, smooth and reliable microscopic machines, and tough mechanical tools. Yet it's been an outsider. Laboratories have been effectively growing diamond crystals for at least 25 years, but the jump to market viability has always been blocked by the expense of diamond production and inability to integrate with other materials. Advances in chemical vapor deposition (CVD) processes have given rise to a hierarchy of carbon films ranging from diamond-like carbon (DLC) to vapor-deposited diamond coatings, however. All have pros and cons based on structure and cost, but they all share some of diamond's heralded attributes. The best performer, in theory, is the purest form of diamond film possible, one absent of graphitic phases. Such a material would capture the extreme hardness, high Young's modulus and chemical inertness of natural diamond. Advanced Diamond Technologies Inc., Romeoville, Ill., is the first company to develop a distinct chemical process to create a marketable phase-pure diamond film. The material, called UNCD® (for ultrananocrystalline diamond), features grain sizes from 3 to 300 nm in size, and layers just 1 to 2 microns thick. With significant advantages over other thin films, UNCD is designed to be inexpensive enough for use in atomic force microscopy (AFM) probes, microelectromechanical machines (MEMS), cell phone circuitry, radio frequency devices, and even biosensors.

Free-standing nanomechanical and nanophotonic structures in single-crystal diamond

NASA Astrophysics Data System (ADS)

Burek, Michael John

Realizing complex three-dimensional structures in a range of material systems is critical to a variety of emerging nanotechnologies. This is particularly true of nanomechanical and nanophotonic systems, both relying on free-standing small-scale components. In the case of nanomechanics, necessary mechanical degrees of freedom require physically isolated structures, such as suspended beams, cantilevers, and membranes. For nanophotonics, elements like waveguides and photonic crystal cavities rely on light confinement provided by total internal reflection or distributed Bragg reflection, both of which require refractive index contrast between the device and surrounding medium (often air). Such suspended nanostructures are typically fabricated in a heterolayer structure, comprising of device (top) and sacrificial (middle) layers supported by a substrate (bottom), using standard surface nanomachining techniques. A selective, isotropic etch is then used to remove the sacrificial layer, resulting in free-standing devices. While high-quality, crystalline, thin film heterolayer structures are readily available for silicon (as silicon-on-insulator (SOI)) or III-V semiconductors (i.e. GaAs/AlGaAs), there remains an extensive list of materials with attractive electro-optic, piezoelectric, quantum optical, and other properties for which high quality single-crystal thin film heterolayer structures are not available. These include complex metal oxides like lithium niobate (LiNbO3), silicon-based compounds such as silicon carbide (SiC), III-V nitrides including gallium nitride (GaN), and inert single-crystals such as diamond. Diamond is especially attractive for a variety of nanoscale technologies due to its exceptional physical and chemical properties, including high mechanical hardness, stiffness, and thermal conductivity. Optically, it is transparent over a wide wavelength range (from 220 nm to the far infrared), has a high refractive index (n ~ 2.4), and is host to a vast inventory of luminescent defect centers (many with direct optical access to highly coherent electron and nuclear spins). Diamond has many potential applications ranging from radio frequency nanoelectromechanical systems (RF-NEMS), to all-optical signal processing and quantum optics. Despite the commercial availability of wafer-scale nanocrystalline diamond thin films on foreign substrates (namely SiO2), this diamond-on-insulator (DOI) platform typically exhibits inferior material properties due to friction, scattering, and absorption losses at grain boundaries, significant surface roughness, and large interfacial stresses. In the absence of suitable heteroepitaxial diamond growth, substantial research and development efforts have focused on novel processing techniques to yield nanoscale single-crystal diamond mechanical and optical elements. In this thesis, we demonstrate a scalable 'angled-etching' nanofabrication method for realizing nanomechanical systems and nanophotonic networks starting from bulk single-crystal diamond substrates. Angled-etching employs anisotropic oxygen-based plasma etching at an oblique angle to the substrate surface, resulting in suspended optical structures with triangular cross-sections. Using this approach, we first realize single-crystal diamond nanomechanical resonant structures. These nanoscale diamond resonators exhibit high mechanical quality-factors (approaching Q ~ 105) with mechanical resonances up to 10 MHz. Next, we demonstrate engineered nanophotonic structures, specifically racetrack resonators and photonic crystal cavities, in bulk single-crystal diamond. Our devices feature large optical Q-factors, in excess of 10 5, and operate over a wide wavelength range, spanning visible and telecom. These newly developed high-Q diamond optical nanocavities open the door for a wealth of applications, ranging from nonlinear optics and chemical sensing, to quantum information processing and cavity optomechanics. Beyond isolated nanophotonic devices, we also developed free-standing angled-etched diamond waveguides which efficiently route photons between optical nanocavities, realizing true on-chip diamond nanophotonic networks. A high efficiency fiber-optical interface with aforementioned on-chip diamond nanophotonic networks, achieving > 90% power coupling, is also demonstrated. Lastly, we demonstrate a cavity-optomechanical system in single-crystal diamond, which builds upon previously realized diamond nanobeam photonic crystal cavities fabricated by angled-etching. Specifically, we demonstrate diamond optomechanical crystals (OMCs), where the engineered co-localization of photons and phonons in a quasi-periodic diamond nanostructure leads to coupling of an optical cavity field to a mechanical mode via the radiation pressure of light. In contrast to other material systems, diamond OMCs possess large intracavity photon capacity and sufficient optomechanical coupling rates to exceed a cooperativity of ~ 1 at room temperature and realize large amplitude optomechanical self-oscillations.

Body dysmorphic disorder: Latest neuroanatomical and neuropsychological findings.

PubMed

Tasios, K; Michopoulos, I

2017-01-01

Body dysmorphic disorder (BDD) is characterized by a preoccupation with a perceived defect or flaw in physical appearance that is not observable or appears slight to others. It leads to severe distress and functional impairment. Cognitive-behavioural and neurobiological similarities to obsessive compulsive disorder (OCD) have led to its newly conceived classification as an obsessive compulsive related disorder (OCRD). In the process of investigating the neurobiology of BDD, neuroimaging and neuropsychological studies have been conducted. This review presents the most recent research findings and their connection with BDD clinical features. Imaging studies have shown increased total white matter volume and caudate volume asymmetry in BDD patients. These findings are consistent with the striatal topography model of OCRDs. Other studies have showed perfusion deficits in bilateral anterior-medial temporal and occipital regions and asymmetric perfusion in parietal lobes. In addition, correlation between symptom severity and left inferior frontal gyrus volume reflects the degree of detailed, analytic encoding that occurs on day-to-day basis when viewing others and themselves, and that likely underlies their symptoms. Finally, positive correlation between right amygdala volume and symptom severity signifies pathological fear circuitry engagement, hypervigilance and heightened sensitivity to social situations. Neuropsychological studies of BDD reveal deficits in strategic organization, learning and free recall after short and long delays. Executive function deficits are related to spatial working memory and subsequent thinking speed as well as impaired higher level planning ability. BDD patients' organizational strategies tend to focus on detail rather than on larger, global clustering features. They are characterized by abnormal visual processing of both details and global elements, inaccurate processing of global elements and reduced flexibility in switching visual attention between global and local features. Moreover, BDD patients seem to have deficits in identifying facial emotional expressions and they tend to misinterpret expressions of disgust (and others) as anger. Poor insight and ideas of reference, common in BDD, might be related to emotion recognition biases for angry expressions. These findings have been supplemented by combined neuroimaging and neuropsychological studies. Left hemisphere hyperactivity for low and normal spatial frequency face tasks and abnormal activation of the amygdala for high and low spatial frequency face tasks suggests detail encoding and analysis in BDD. Patients may primarily perceive details but they are impaired in their ability to contextualize them holistically.

Cognitive-behavioral therapy for body dysmorphic disorder: A systematic review and meta-analysis of randomized controlled trials.

PubMed

Harrison, Amy; Fernández de la Cruz, Lorena; Enander, Jesper; Radua, Joaquim; Mataix-Cols, David

2016-08-01

Body dysmorphic disorder (BDD) is a chronic and disabling psychiatric disorder unlikely to remit without treatment. A systematic review and meta-analysis of randomized controlled trials (RCTs) of cognitive-behavioral therapy (CBT) for BDD was conducted, including published and unpublished trials to 26th November 2015. Primary outcomes were validated BDD measures; secondary outcomes included depression and insight. Meta-regressions were conducted to examine potential effects of variables on the primary outcome, including socio-demographic variables, comorbidity, symptom severity/duration, concomitant medication, treatment duration, and methodological quality of the RCTs. Seven RCTs (N=299) met inclusion criteria. CBT was superior to waitlist or credible psychological placebo in reducing BDD (7 studies; delta=-1.22, 95% CI=-1.66 to -0.79) and depression symptoms (5 studies; delta=-0.49, 95% CI=-0.76 to -0.22). CBT was associated with improvements in insight/delusionality (4 studies; delta=-0.56, 95% CI=-0.93 to -0.19). Improvement in BDD was maintained after 2-4months follow-up (3 studies; delta=-0.89, 95% CI=-1.24 to -0.54). Meta-regression analyses did not reveal any significant predictors of outcome. CBT is an efficacious treatment for BDD but there is substantial room for improvement. The specificity and long-term effects of CBT for BDD require further evaluation using credible control conditions. Additional trials comparing CBT with pharmacological therapies, as well as their combination, are warranted. Tele-care options, such as Internet-based CBT, hold great promise to increase access to evidence-based treatment for a majority of patients who need it and should be evaluated further. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparing the curative efficacy of topical treatment with thiamphenicol and oxytetracycline on digital dermatitis lesions in dairy cattle.

PubMed

Holzhauer, M; Ploegmakers-van Deventer, R; Smits, D; Swart, W

2017-05-20

The efficacy of two topically applied antibiotics for the treatment of painful ulcerative stage of bovine digital dermatitis (BDD) lesions was compared in a clinical trial conducted on five dairy farms in the Netherlands during the autumn of 2015. A total of 109 cows with an ulcerative (M2) stage of BDD were randomly appointed a treatment with an antibiotic-based spray. One treatment contained thiamphenicol as active ingredient (TAF). The other treatment had oxytetracycline as active ingredient (ENG). The experimental unit for this study was the hind claw with the presence of an ulcerative BDD lesion. On day 0, claws with ulcerative BDD lesions were trimmed, cleaned, photographed and thereafter treated randomly either with TAF or ENG. Cure was defined as the transition of an ulcerative lesion into a non-painful chronic (M4) or into a healed (M0) stage of BDD at day 28 post-treatment. The cure rate at day 28 of M2 BDD lesions treated with TAF was 89 per cent (95 per cent CI 0.78 to 0.94), and for ENG 75 per cent (95 per cent CI 0.67 to 0.86). So the difference in cure rate was 14 per cent (95 per cent CI 0.00 to 0.27), which was statistically significant. The P value in this experiment is very close to 0.05 indicating that the effect is quite small. If a two-sided test would be used, the small significant effect, in this experiment, will disappear. Overall, the significant better curative effect of TAF on BDD M2 lesions was small, compared with ENG. British Veterinary Association.

Modifying interpretation biases in body dysmorphic disorder: Evaluation of a brief computerized treatment.

PubMed

Summers, Berta J; Cougle, Jesse R

2016-12-01

Individuals meeting diagnostic criteria for body dysmorphic disorder (BDD; N = 40) were enrolled in a randomized, four-session trial comparing interpretation bias modification (IBM) training designed to target social evaluation- and appearance-related interpretation biases with a placebo control training condition (PC). Sessions took place over the course of two weeks (two sessions per week). Analyses indicated that, relative to the PC condition, IBM led to a significant increase in benign biases and reduction in threat biases at post-treatment. IBM also led to greater reductions in BDD symptoms compared to PC, though this effect was present at high but not low levels of pre-treatment BDD symptoms. Additionally, compared to PC, IBM led to lower urge to check and lower fear in response to an in vivo appearance-related stressor (having their picture taken from different angles), though the latter effect was present only among those reporting elevated fear at pre-treatment. The effects of treatment on interpretation biases and BDD symptoms were largely maintained at a one-month follow-up assessment. Moderated-mediation analyses showed that change in threat bias mediated the effect of condition on post-treatment symptoms for individuals high in pre-treatment BDD symptoms. The current study provides preliminary support for the efficacy of IBM for BDD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prevalence of Body Dysmorphic Disorder and Muscle Dysmorphia Among Entry-Level Military Personnel.

PubMed

Campagna, John D A; Bowsher, Barbara

2016-05-01

To determine the prevalence of body dysmorphic disorder (BDD) and muscle dysmorphia (MD) in enlisted U.S. military personnel; and secondarily, to determine supplement use and relationship with BDD and MD. A survey of advanced individual training of tri-service personnel at Fort Sam Houston, Texas, was performed combining the dysmorphia concern questionnaire, the MD symptom questionnaire, a supplement questionnaire, and demographic factors. Of the 1,320 service members approached, 1,150 (87.1%) completed the survey. The majority of participants were male, 62.8% (n = 722) and Army soldiers 59.0% (n = 679). The prevalence rate of BDD was 13.0% in males and 21.7% in females. The prevalence of MD was 12.7% in males and 4.2% in females. There was a strong correlation between having BDD and using supplements to get thinner (odds ratio 5.1; 95% confidence interval 3.4-7.8; p < 0.001) and MD to get more muscular (odds ratio 5.4; 95% confidence interval 3.5-8.3; p < 0.001). Our study shows a higher than expected prevalence rate of BDD and MD in service members. This indicates a need for increased awareness of dysmorphias in mental health providers, primary care providers, and commanders and justifies further military specific BDD and MD research. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Phenomenology of men with body dysmorphic disorder concerning penis size compared to men anxious about their penis size and to men without concerns: a cohort study.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Carmona, Lina; Fiorito, Chiara; Wells, Hannah; Wylie, Kevan; Muir, Gordon

2015-03-01

Men with body dysmorphic disorder (BDD) may be preoccupied with the size or shape of the penis, which may be causing significant shame or impairment. Little is known about the characteristics and phenomenology of such men and whether they can be differentiated from men with small penis anxiety (SPA) (who do not have BDD), and men with no penile concerns. Twenty-six men with BDD, 31 men with SPA, and 33 men without penile concerns were compared on psychopathology, experiences of recurrent imagery, avoidance and safety-seeking behaviours. Men with BDD had significantly higher scores than both the SPA group and no penile concern group for measures of imagery, avoidance, safety seeking and general psychopathology. The groups differed on the phenomenology of BDD specific to penile size preoccupation clearly from the worries of SPA, which in turn were different to those of the men without concerns. The common avoidance and safety seeking behaviours were identified in such men that may be used clinically. Copyright © 2014 Elsevier Ltd. All rights reserved.

Low-Energy, Hydrogen-Free Method of Diamond Synthesis

NASA Technical Reports Server (NTRS)

Varshney, Deepak (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor); Makarov, Vladimir (Inventor)

2013-01-01

Diamond thin films were deposited on copper substrate by the Vapor Solid (VS) deposition method using a mixture of fullerene C(sub 60) and graphite as the source material. The deposition took place only when the substrate was kept in a narrow temperature range of approximately 550-650 C. Temperatures below and above this range results in the deposition of fullerenes and other carbon compounds, respectively.

Muscle dysmorphia: a South African sample.

PubMed

Hitzeroth, V; Wessels, C; Zungu-Dirwayi, N; Oosthuizen, P; Stein, D J

2001-10-01

It has recently been suggested that muscle dysmorphia, a pathological preoccupation with muscularity, is a subtype of body dysmorphic disorder (BDD). There are, however, few studies of the phenomenology of this putative entity. Twenty-eight amateur competitive body builders in the Western Cape, South Africa, were studied using a structured diagnostic interview that incorporated demographic data, body-building activities and clinical questions focusing on muscle dysmorphia and BDD. There was a high rate of muscle dysmorphia in the sample (53.6%). Those with muscle dysmorphia were significantly more likely to have comorbid BDD based on preoccupations other than muscularity (33%). Use of the proposed diagnostic criteria for muscle dysmorphia indicated that this is a common and relevant entity. Its conceptualization as a subtype of BDD seems valid. The disorder deserves additional attention from both clinicians and researchers.

Thin film diamond temperature sensor array for harsh aerospace environment

NASA Technical Reports Server (NTRS)

Aslam, M.; Masood, A.; Fredricks, R. J.; Tamor, M. A.

1992-01-01

The feasibility of using polycrystalline CVD diamond films as temperature sensors in harsh aerospace environment associated with hypersonic flights was tested using patterned diamond resistors, fabricated on flat or curved oxidized Si surfaces, as temperature sensors at temperatures between 20 and 1000 C. In this temperature range, the measured resistance was found to vary over 3 orders of magnitude and the temperature coefficient of resistance to change from 0.017/K to 0.003/K. After an annealing treatment, the resistance change was reproducible within 1 percent on the entire temperature range for short measuring times.

Ultrahard carbon film from epitaxial two-layer graphene

NASA Astrophysics Data System (ADS)

Gao, Yang; Cao, Tengfei; Cellini, Filippo; Berger, Claire; de Heer, Walter A.; Tosatti, Erio; Riedo, Elisa; Bongiorno, Angelo

2018-02-01

Atomically thin graphene exhibits fascinating mechanical properties, although its hardness and transverse stiffness are inferior to those of diamond. So far, there has been no practical demonstration of the transformation of multilayer graphene into diamond-like ultrahard structures. Here we show that at room temperature and after nano-indentation, two-layer graphene on SiC(0001) exhibits a transverse stiffness and hardness comparable to diamond, is resistant to perforation with a diamond indenter and shows a reversible drop in electrical conductivity upon indentation. Density functional theory calculations suggest that, upon compression, the two-layer graphene film transforms into a diamond-like film, producing both elastic deformations and sp2 to sp3 chemical changes. Experiments and calculations show that this reversible phase change is not observed for a single buffer layer on SiC or graphene films thicker than three to five layers. Indeed, calculations show that whereas in two-layer graphene layer-stacking configuration controls the conformation of the diamond-like film, in a multilayer film it hinders the phase transformation.

Diamond and Carbon Nanotube Composites for Supercapacitor Devices

NASA Astrophysics Data System (ADS)

Moreira, João Vitor Silva; May, Paul William; Corat, Evaldo José; Peterlevitz, Alfredo Carlos; Pinheiro, Romário Araújo; Zanin, Hudson

2017-02-01

We report on the synthesis and electrochemical properties of diamond grown onto vertically aligned carbon nanotubes with high surface areas as a template, resulting in a composite material exhibiting high double-layer capacitance as well as low electrochemical impedance electrodes suitable for applications as supercapacitor devices. We contrast results from devices fabricated with samples which differ in both their initial substrates (Si and Ti) and their final diamond coatings, such as boron-doped diamond and diamond-like carbon (DLC). We present for first time a conducting model for non-doped DLC thin-films. All samples were characterized by scanning and transmission electron microscopy and Fourier transform infrared and Raman spectroscopy. Our results show specific capacitance as high as 8.25 F g-1 (˜1 F cm-2) and gravimetric specific energy and power as high as 0.7 W h kg-1 and 176.4 W kg-1, respectively, which suggest that these diamond/carbon nanotube composite electrodes are excellent candidates for supercapacitor fabrication.

Microcrystalline diamond cylindrical resonators with quality-factor up to 0.5 million

NASA Astrophysics Data System (ADS)

Saito, Daisuke; Yang, Chen; Heidari, Amir; Najar, Hadi; Lin, Liwei; Horsley, David A.

2016-02-01

We demonstrate high quality-factor 1.5 mm diameter batch-fabricated microcrystalline diamond cylindrical resonators (CR) with quality-factors limited by thermoelastic damping (TED) and surface loss. Resonators were fabricated 2.6 and 5.3 μm thick in-situ boron-doped microcrystalline diamond films deposited using hot filament chemical vapor deposition. The quality-factor (Q) of as-fabricated CR's was found to increase with the resonator diameter and diamond thickness. Annealing the CRs at 700 °C in a nitrogen atmosphere led to a three-fold increase in Q, a result we attribute to thinning of the diamond layer via reaction with residual O2 in the annealing furnace. Post-anneal Q exceeding 0.5 million (528 000) was measured at the 19 kHz elliptical wineglass modes, producing a ring-down time of 8.9 s. A model for Q versus diamond thickness and resonance frequency is developed including the effects of TED and surface loss. Measured quality factors are shown to agree with the predictions of this model.

Long-term culture of pluripotent stem-cell-derived human neurons on diamond--A substrate for neurodegeneration research and therapy.

PubMed

Nistor, Paul A; May, Paul W; Tamagnini, Francesco; Randall, Andrew D; Caldwell, Maeve A

2015-08-01

Brain Computer Interfaces (BCI) currently represent a field of intense research aimed both at understanding neural circuit physiology and at providing functional therapy for traumatic or degenerative neurological conditions. Due to its chemical inertness, biocompatibility and stability, diamond is currently being actively investigated as a potential substrate material for culturing cells and for use as the electrically active component of a neural sensor. Here we provide a protocol for the differentiation of mature, electrically active neurons on microcrystalline synthetic thin-film diamond substrates starting from undifferentiated pluripotent stem cells. Furthermore, we investigate the optimal characteristics of the diamond microstructure for long-term neuronal sustainability. We also analyze the effect of boron as a dopant for such a culture. We found that the diamond crystalline structure has a significant influence on the neuronal culture unlike the boron doping. Specifically, small diamond microcrystals promote higher neurite density formation. We find that boron incorporated into the diamond does not influence the neurite density and has no deleterious effect on cell survival. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Optical properties of diamond like carbon nanocomposite thin films

NASA Astrophysics Data System (ADS)

Alam, Md Shahbaz; Mukherjee, Nillohit; Ahmed, Sk. Faruque

2018-05-01

The optical properties of silicon incorporated diamond like carbon (Si-DLC) nanocomposite thin films have been reported. The Si-DLC nanocomposite thin film deposited on glass and silicon substrate by radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) process. Fourier transformed infrared spectroscopic analysis revealed the presence of different bonding within the deposited films and deconvolution of FTIR spectra gives the chemical composition i.e., sp3/sp2 ratio in the films. Optical band gap calculated from transmittance spectra increased from 0.98 to 2.21 eV with a variation of silicon concentration from 0 to 15.4 at. %. Due to change in electronic structure by Si incorporation, the Si-DLC film showed a broad photoluminescence (PL) peak centered at 467 nm, i.e., in the visible range and its intensity was found to increase monotonically with at. % of Si.

Magnetic tunnel junctions utilizing diamond-like carbon tunnel barriers

NASA Astrophysics Data System (ADS)

Cadieu, F. J.; Chen, Li; Li, Biao

2002-05-01

We have devised a method whereby thin particulate-free diamond-like carbon films can be made with good adhesion onto even room-temperature substrates. The method employs a filtered ionized carbon beam created by the vacuum impact of a high-energy, approximately 1 J per pulse, 248 nm excimer laser onto a carbon target. The resultant deposition beam can be steered and deflected by magnetic and electric fields to paint a specific substrate area. An important aspect of this deposition method is that the resultant films are particulate free and formed only as the result of atomic species impact. The vast majority of magnetic tunnel junctions utilizing thin metallic magnetic films have employed a thin oxidized layer of aluminum to form the tunnel barrier. This has presented reproducibility problems because the indicated optimal barrier thickness is only approximately 13 Å thick. Magnetic tunnel junctions utilizing Co and permalloy films made by evaporation and sputtering have been fabricated with an intervening diamond-like carbon tunnel barrier. The diamond-like carbon thickness profile has been tapered so that seven junctions with different barrier thickness can be formed at once. Magnetoresistive (MR) measurements made between successive permalloy strip ends include contributions from two junctions and from the permalloy and Co strips that act as current leads to the junctions. Magnetic tunnel junctions with thicker carbon barriers exhibit MR effects that are dominated by that of the permalloy strips. Since these tunnel barriers are formed without the need for oxygen, complete tunnel junctions can be formed with all high-vacuum processing.

Diamond Coatings

NASA Technical Reports Server (NTRS)

1990-01-01

Advances in materials technology have demonstrated that it is possible to get the advantages of diamond in a number of applications without the cost penalty, by coating and chemically bonding an inexpensive substrate with a thin film of diamond-like carbon (DLC). Diamond films offer tremendous technical and economic potential in such advances as chemically inert protective coatings; machine tools and parts capable of resisting wear 10 times longer; ball bearings and metal cutting tools; a broad variety of optical instruments and systems; and consumer products. Among the American companies engaged in DLC commercialization is Diamonex, Inc., a diamond coating spinoff of Air Products and Chemicals, Inc. Along with its own proprietary technology for both polycrystalline diamond and DLC coatings, Diamonex is using, under an exclusive license, NASA technology for depositing DLC on a substrate. Diamonex is developing, and offering commercially, under the trade name Diamond Aegis, a line of polycrystalline diamond-coated products that can be custom tailored for optical, electronic and engineering applications. Diamonex's initial focus is on optical products and the first commercial product is expected in late 1990. Other target applications include electronic heat sink substrates, x-ray lithography masks, metal cutting tools and bearings.

Structural and optical properties of gold-incorporated diamond-like carbon thin films deposited by RF magnetron sputtering

NASA Astrophysics Data System (ADS)

Majeed, Shahbaz; Siraj, K.; Naseem, S.; Khan, Muhammad F.; Irshad, M.; Faiz, H.; Mahmood, A.

2017-07-01

Pure and gold-doped diamond-like carbon (Au-DLC) thin films are deposited at room temperature by using RF magnetron sputtering in an argon gas-filled chamber with a constant flow rate of 100 sccm and sputtering time of 30 min for all DLC thin films. Single-crystal silicon (1 0 0) substrates are used for the deposition of pristine and Au-DLC thin films. Graphite (99.99%) and gold (99.99%) are used as co-sputtering targets in the sputtering chamber. The optical properties and structure of Au-DLC thin films are studied with the variation of gold concentration from 1%-5%. Raman spectroscopy, atomic force microscopy (AFM), Vickers hardness measurement (VHM), and spectroscopic ellipsometry are used to analyze these thin films. Raman spectroscopy indicates increased graphitic behavior and reduction in the internal stresses of Au-DLC thin films as the function of increasing gold doping. AFM is used for surface topography, which shows that spherical-like particles are formed on the surface, which agglomerate and form larger clusters on the surface by increasing the gold content. Spectroscopy ellipsometry analysis elucidates that the refractive index and extinction coefficient are inversely related and the optical bandgap energy is decreased with increasing gold content. VHM shows that gold doping reduces the hardness of thin films, which is attributed to the increase in sp2-hybridization.

New perspectives in the treatment of body dysmorphic disorder

PubMed Central

Hong, Kevin; Nezgovorova, Vera; Hollander, Eric

2018-01-01

Body dysmorphic disorder (BDD) is a disabling illness with a high worldwide prevalence. Patients demonstrate a debilitating preoccupation with one or more perceived defects, often marked by poor insight or delusional convictions. Multiple studies have suggested that selective serotonin reuptake inhibitors and various cognitive behavioral therapy modalities are effective first-line treatments in decreasing BDD severity, relieving depressive symptoms, restoring insight, and increasing quality of life. Selective serotonin reuptake inhibitors have also recently been shown to be effective for relapse prevention. This review provides a comprehensive summary of the current understanding of BDD, including its clinical features, epidemiology, genetics, and current treatment modalities. Additional research is needed to fully elucidate the relationship between BDD and comorbid illnesses such as obsessive–compulsive-related disorders and depression and to develop therapies for refractory patients and those who have contraindications for pharmacological intervention. PMID:29636904

How do people with body dysmorphic disorder view themselves? A thematic analysis.

PubMed

Silver, Joanna; Reavey, Paula; Anne Fineberg, Naomi

2010-09-01

Abstract Objectives. To examine the accounts of people with body dysmorphic disorder (BDD) and qualitatively explore self perceptions. Methods. Eleven people with BDD were interviewed using a semi-structured schedule. Participants brought photographs of themselves and drew a self-portrait. Transcribed interviews were analysed using a thematic analysis. Results. The most common theme was increased threat perception resulting in disordered interpersonal relationships. Other themes included the wish for regularity and symmetry in appearance, an idealised childhood self, the duty to look good, and a focus on specific "defective" features rather than general ugliness. Conclusions. Using thematic analysis and visual methods, we identified core themes that appear to characterise the way individuals with BDD perceive themselves and their interpersonal relationships. Thematic analysis offers promise as a tool to explore the overlap between BDD and other putatively related mental health problems.

Recent advances in understanding and managing body dysmorphic disorder

PubMed Central

Krebs, Georgina; Fernández de la Cruz, Lorena; Mataix-Cols, David

2017-01-01

Body dysmorphic disorder (BDD) is a relatively common and disabling psychiatric disorder characterised by excessive and persistent preoccupation with perceived defects or flaws in one's appearance, which are unnoticeable to others, and associated repetitive behaviours (eg, mirror checking). The disorder generally starts in adolescence, but often goes unnoticed and is severely underdiagnosed. Left untreated, BDD typically persists and causes marked functional impairment in multiple domains. This clinical review considers recent advances in the epidemiology and classification of BDD, including its reclassification in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders under the new ‘Obsessive–Compulsive and Related Disorders’ chapter. Key issues in assessment are outlined including the use of validated screening instruments to minimise misdiagnosis and the importance of risk assessment in this population given the high rates of suicidality and inappropriate use of cosmetic treatments. In addition, current knowledge regarding the causes and mechanisms underlying BDD are summarised. The recommended treatments for BDD are outlined, namely cognitive behavioural therapy (CBT) and antidepressants, such as selective serotonin reuptake inhibitors. Both CBT and pharmacotherapy have been shown to be efficacious treatments for BDD in adult populations, and evidence is emerging to support their use in young people. Although the majority of patients improve with existing evidence-based treatment, a large proportion are left with clinically significant residual symptoms. Priorities for future research are therefore discussed including the need to further refine and evaluate existing interventions with the goal of improving treatment outcomes and to increase their availability. PMID:28729345

Adjunctive antipsychotic in the treatment of body dysmorphic disorder - A retrospective naturalistic case note study.

PubMed

Rashid, Haroon; Khan, Akif A; Fineberg, Naomi A

2015-06-01

A retrospective naturalistic case note study to determine the frequency, co-morbidity and treatment-response of body dysmorphic disorder (BDD). Records from 280 patients attending a highly specialised obsessive-compulsive disorder (OCD)/BDD service were analysed. The clinical outcome was measured either through scoring of the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) for OCD/BDD, or textual analysis of case notes for evidence of symptomatic improvement, treatment tolerability, and premature disengagement. A total of 32 patients (11.43%) were diagnosed with BDD. Of these, 28 (87.5%) had at least one co-morbidity. All patients were offered cognitive behavioural therapy (CBT) and selective serotonin reuptake inhibitor (SSRI). Adjunctive low-dose antipsychotic was prescribed for 21 (66%) patients. Overall, 18/32 (56%) responded, and 7/32 (22%) disengaged prematurely. Patients offered antipsychotic, SSRI and CBT (n = 21) were compared with those offered SSRI and CBT only (n = 11). The treatment was well-tolerated. Whereas there was no significant inter-group difference in the clinical response rate, premature disengagement occurred less frequently in the antipsychotic-treated patients (9.5% versus 45%; Fisher's Exact Test P = 0.0318). BDD frequently presents with co-morbidity, treatment-resistance and premature disengagement. Adjunctive antipsychotic was associated with significantly better treatment adherence, but responder rates did not differ significantly, possibly related to the small sample-size. A well-powered randomised controlled study is warranted, to determine clinical outcomes with adjunctive antipsychotic in BDD.

Prevalence of Body Dysmorphic Disorder Among Patients Seeking Breast Reconstruction.

PubMed

Metcalfe, Drew B; Duggal, Claire S; Gabriel, Allen; Nahabedian, Maurice Y; Carlson, Grant W; Losken, Albert

2014-07-01

Body dysmorphic disorder (BDD) is characterized by a preoccupation with a slight or imagined defect in physical appearance. It has significant implications for patients who desire breast reconstruction, because patient satisfaction with the aesthetic outcome is a substantial contributor to the success of the procedure. The authors estimated the prevalence of BDD among women seeking breast reconstruction by surveying patients with the previously validated Dysmorphic Concerns Questionnaire (DCQ). One hundred eighty-eight women who presented for immediate or delayed breast reconstruction completed the DCQ anonymously, during initial consultation with a plastic surgeon. Two groups of respondents were identified: those who desired immediate reconstruction and those who planned to undergo delayed reconstruction. The prevalence of BDD among breast reconstruction patients was compared between the 2 groups, and the overall prevalence was compared with published rates for the general public. Body dysmorphic disorder was significantly more prevalent in breast reconstruction patients than in the general population (17% vs 2%; P < .001). It also was much more common among patients who planned to undergo delayed (vs immediate) reconstruction (34% vs 13%; P = .004). Relative to the general public, significantly more women who sought breast reconstruction were diagnosed as having BDD. Awareness of the potential for BDD will enable clinicians to better understand their patients' perspectives and discuss realistic expectations at the initial consultation. Future studies are warranted to examine the implications of BDD on patient satisfaction with reconstructive surgery. 3. © 2014 The American Society for Aesthetic Plastic Surgery, Inc.

Diminution of Heart Rate Variability in Bipolar Depression

PubMed Central

Hage, Brandon; Britton, Briana; Daniels, David; Heilman, Keri; Porges, Stephen W.; Halaris, Angelos

2017-01-01

Autonomic nervous system (ANS) dysregulation in depression is associated with symptoms associated with the ANS. The beat-to-beat pattern of heart rate defined as heart rate variability (HRV) provides a noninvasive portal to ANS function and has been proposed to represent a means of quantifying resting vagal tone. We quantified HRV in bipolar depressed (BDD) patients as a measure of ANS dysregulation seeking to establish HRV as a potential diagnostic and prognostic biomarker for treatment outcome. Forty-seven BDD patients were enrolled. They were randomized to receive either escitalopram–celecoxib or escitalopram-placebo over 8 weeks in a double-blind study design. Thirty-five patients completed the HRV studies. Thirty-six healthy subjects served as controls. HRV was assessed at pretreatment and end of study and compared with that of controls. HRV was quantified and corrected for artifacts using an algorithm that incorporates time and frequency domains to address non-stationarity of the beat-to-beat heart rate pattern. Baseline high frequency-HRV (i.e., respiratory sinus arrhythmia) was lower in BDD patients than controls, although the difference did not reach significance. Baseline low-frequency HRV was significantly lower in BDD patients (ln4.20) than controls (ln = 5.50) (p < 0.01). Baseline heart period was significantly shorter (i.e., faster heart rate) in BDD patients than controls. No significant change in HRV parameters were detected over the course of the study with either treatment. These findings suggest that components of HRV may be diminished in BDD patients. PMID:29270399

Improvements in the Formation of Boron-Doped Diamond Coatings on Platinum Wires Using the Novel Nucleation Process (NNP)

PubMed Central

Fhaner, Mathew; Zhao, Hong; Bian, Xiaochun; Galligan, James J.; Swain, Greg M.

2010-01-01

In order to increase the initial nucleation density for the growth of boron-doped diamond on platinum wires, we employed the novel nucleation process (NNP) originally developed by Rotter et al. and discussed by others [1–3]. This pretreatment method involves (i) the initial formation of a thin carbon layer over the substrate followed by (ii) ultrasonic seeding of this “soft” carbon layer with nanoscale particles of diamond. This two-step pretreatment is followed by the deposition of boron-doped diamond by microwave plasma-assisted CVD. Both the diamond seed particles and sites on the carbon layer itself function as the initial nucleation zones for diamond growth from an H2-rich source gas mixture. We report herein on the characterization of the pre-growth carbon layer formed on Pt as well as boron-doped films grown for 2, 4 and 6 h post NNP pretreatment. Results from scanning electron microscopy, Raman spectroscopy and electrochemical studies are reported. The NNP method increases the initial nucleation density on Pt and leads to the formation of a continuous diamond film in a shorter deposition time than is typical for wires pretreated by conventional ultrasonic seeding. The results indicate that the pregrowth layer itself consists of nanoscopic domains of diamond and functions well to enhance the initial nucleation of diamond without any diamond powder seeding. PMID:21617759

Therapist guided internet based cognitive behavioural therapy for body dysmorphic disorder: single blind randomised controlled trial.

PubMed

Enander, Jesper; Andersson, Erik; Mataix-Cols, David; Lichtenstein, Linn; Alström, Katarina; Andersson, Gerhard; Ljótsson, Brjánn; Rück, Christian

2016-02-02

To evaluate the efficacy of therapist guided internet based cognitive behavioural therapy (CBT) programme for body dysmorphic disorder (BDD-NET) compared with online supportive therapy. A 12 week single blind parallel group randomised controlled trial. Academic medical centre. 94 self referred adult outpatients with a diagnosis of body dysmorphic disorder and a modified Yale-Brown obsessive compulsive scale (BDD-YBOCS) score of ≥ 20. Concurrent psychotropic drug treatment was permitted if the dose had been stable for at least two months before enrolment and remained unchanged during the trial. Participants received either BDD-NET (n=47) or supportive therapy (n=47) delivered via the internet for 12 weeks. The primary outcome was the BDD-YBOCS score after treatment and follow-up (three and six months from baseline) as evaluated by a masked assessor. Responder status was defined as a ≥ 30% reduction in symptoms on the scale. Secondary outcomes were measures of depression (MADRS-S), global functioning (GAF), clinical global improvement (CGI-I), and quality of life (EQ5D). The six month follow-up time and all outcomes other than BDD-YBOCS and MADRS-S at 3 months were not pre-specified in the registration at clinicaltrials.gov because of an administrative error but were included in the original trial protocol approved by the regional ethics committee before the start of the trial. BDD-NET was superior to supportive therapy and was associated with significant improvements in severity of symptoms of body dysmorphic disorder (BDD-YBOCS group difference -7.1 points, 95% confidence interval -9.8 to -4.4), depression (MADRS-S group difference -4.5 points, -7.5 to -1.4), and other secondary measures. At follow-up, 56% of those receiving BDD-NET were classed as responders, compared with 13% receiving supportive therapy. The number needed to treat was 2.34 (1.71 to 4.35). Self reported satisfaction was high. CBT can be delivered safely via the internet to patients with body dysmorphic disorder. BDD-NET has the potential to increase access to evidence based psychiatric care for this mental disorder, in line with NICE priority recommendations. It could be particularly useful in a stepped care approach, in which general practitioner or other mental health professionals can offer treatment to people with mild to moderate symptoms at low risk of suicide.Trial registration ClinicalTrials.gov ID: NCT02010619. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Therapist guided internet based cognitive behavioural therapy for body dysmorphic disorder: single blind randomised controlled trial

PubMed Central

Andersson, Erik; Mataix-Cols, David; Lichtenstein, Linn; Alström, Katarina; Andersson, Gerhard; Ljótsson, Brjánn; Rück, Christian

2016-01-01

Objectives To evaluate the efficacy of therapist guided internet based cognitive behavioural therapy (CBT) programme for body dysmorphic disorder (BDD-NET) compared with online supportive therapy. Design A 12 week single blind parallel group randomised controlled trial. Setting Academic medical centre. Participants 94 self referred adult outpatients with a diagnosis of body dysmorphic disorder and a modified Yale-Brown obsessive compulsive scale (BDD-YBOCS) score of ≥20. Concurrent psychotropic drug treatment was permitted if the dose had been stable for at least two months before enrolment and remained unchanged during the trial. Interventions Participants received either BDD-NET (n=47) or supportive therapy (n=47) delivered via the internet for 12 weeks. Main outcome measures The primary outcome was the BDD-YBOCS score after treatment and follow-up (three and six months from baseline) as evaluated by a masked assessor. Responder status was defined as a ≥30% reduction in symptoms on the scale. Secondary outcomes were measures of depression (MADRS-S), global functioning (GAF), clinical global improvement (CGI-I), and quality of life (EQ5D). The six month follow-up time and all outcomes other than BDD-YBOCS and MADRS-S at 3 months were not pre-specified in the registration at clinicaltrials.gov because of an administrative error but were included in the original trial protocol approved by the regional ethics committee before the start of the trial. Results BDD-NET was superior to supportive therapy and was associated with significant improvements in severity of symptoms of body dysmorphic disorder (BDD-YBOCS group difference −7.1 points, 95% confidence interval −9.8 to −4.4), depression (MADRS-S group difference −4.5 points, −7.5 to −1.4), and other secondary measures. At follow-up, 56% of those receiving BDD-NET were classed as responders, compared with 13% receiving supportive therapy. The number needed to treat was 2.34 (1.71 to 4.35). Self reported satisfaction was high. Conclusions CBT can be delivered safely via the internet to patients with body dysmorphic disorder. BDD-NET has the potential to increase access to evidence based psychiatric care for this mental disorder, in line with NICE priority recommendations. It could be particularly useful in a stepped care approach, in which general practitioner or other mental health professionals can offer treatment to people with mild to moderate symptoms at low risk of suicide. Trial registration ClinicalTrials.gov ID: NCT02010619. PMID:26837684

High-density fluids and the growth of monocrystalline diamonds

NASA Astrophysics Data System (ADS)

Weiss, Y.; Kiflawi, I.; Davies, N.; Navon, O.

2014-09-01

The chemical nature and composition of the growth medium of monocrystalline (MC) diamonds is still a matter of debate, partially because carbonate-bearing high-density fluids (HDFs) that are common in fibrous diamonds have not been found in MC diamonds. Here we report the first finding of HDF microinclusions in a MC octahedral diamond from Finsch, South Africa and in the MC octahedral core of a coated diamond from Kankan, Guinea; both diamonds carry nitrogen in B-centers. Numerous microinclusions in diamond Finsch_2a_cap1 are restricted to two thin layers parallel to the (1 1 1) face, ∼20 and 200 μm from the diamond rim. Low-Mg carbonatitic HDFs are found along the inner layer while the outer layer trapped saline compositions. The major and trace element compositions of the inclusions and their infrared spectra are highly similar to those of microinclusions found in fibrous diamonds. A few isolated microinclusions of saline compositions are scattered around a sulfide inclusion in the center of the octahedral core of diamond ON-KAN-383. This evidence for the involvement of oxidized fluids in the formation of MC diamonds adds to previous reports on the antiquity of HDFs in fibrous diamonds, the presence of carbonate and halide phases in inclusions in MC diamonds and the similarity of trace element pattern of a MC diamond to those of low-Mg carbonatitic HDF in fibrous diamonds. In addition, we show that the interaction of HDFs with depleted garnets can produce sinusoidal REE patterns which are one of the primary features of lherzolitic and harzburgitic garnet inclusions in MC diamonds. Together, these observations suggest that HDFs are involved in the formation of many types of diamonds from the Archaean to the Phanerozoic. HDFs are trapped in large quantities during rapid, fibrous growth, but must also be present during the growth of many MC diamonds.

Cognitive-Behavioral Therapy for Body Dysmorphic Disorder by Proxy.

PubMed

Greenberg, Jennifer L; Mothi, Suraj Sarvode; Wilhelm, Sabine

2016-07-01

Body dysmorphic disorder (BDD) is a distressing or impairing preoccupation with a perceived defect in physical appearance. BDD by proxy (BDDBP) is a significant but understudied variant of BDD in which the primary preoccupation involves perceived imperfections of another person. Like BDD, individuals with BDDBP engage in time-consuming rituals to "fix" the other person's appearance or alleviate distress. Avoidance is common and the impact of BDDBP on social functioning is profound. Cognitive-behavioral therapy (CBT) is the best-studied and most promising psychological treatment for BDD, but no studies have examined its generalizability to the BDDBP variant. We tested feasibility, acceptability, and treatment outcome of CBT modified for BDDBP in a sample of 6 adults with primary BDDBP. Treatment was delivered in weekly individual sessions over 12-20weeks. Mean symptom severity (BDDBP-YBOCS) dropped from the moderately severe range at pretreatment to the subclinical range at posttreatment, t(6)=10.7, p<.001, d=3.3. One hundred percent of treatment completers were responders (≥30% reduction in BDDBP-YBOCS). Insight also improved. Treatment gains were maintained at 3-month follow-up. To our knowledge, this represents the first treatment study for BDDBP. Copyright © 2016. Published by Elsevier Ltd.

Cell micro-irradiation with MeV protons counted by an ultra-thin diamond membrane

NASA Astrophysics Data System (ADS)

Barberet, Philippe; Pomorski, Michal; Muggiolu, Giovanna; Torfeh, Eva; Claverie, Gérard; Huss, Cédric; Saada, Samuel; Devès, Guillaume; Simon, Marina; Seznec, Hervé

2017-12-01

We report the development of thin single crystal diamond membranes suitable for dose control in targeted cell irradiation experiments with a proton microbeam. A specific design was achieved to deliver single protons with a hit detection efficiency approaching 100%. The membranes have thicknesses between 1.8 and 3 μm and are used as vacuum windows on the microbeam line. The impact of these transmission detectors on the microbeam spot size is estimated by Monte-Carlo simulations, indicating that a beam lateral resolution below 2 μm is achieved. This is confirmed by experiments showing the accumulation online of X-ray Repair Cross-Complementing protein 1 (XRCC1)-Green Fluorescent Protein (GFP) at DNA damaged sites in living cells.

Effect of sputtering power on structure, adhesion strength and corrosion resistance of nitrogen doped diamond-like carbon thin films.

PubMed

Khun, N W; Liu, E

2011-06-01

Nitrogen doped diamond-like carbon (DLC:N) thin films were deposited on highly conductive p-Si substrates using a DC magnetron sputtering deposition system. The DLC:N films were characterized using X-ray photoelectron spectroscopy (XPS), micro-Raman spectroscopy, atomic force microscopy (AFM), contact angle measurement and micro-scratch test. The XPS and Raman results indicated that the sputtering power significantly influenced the properties of the films in terms of bonding configuration in the films. The corrosion performance of the DLC:N films was investigated in a 0.6 M NaCl solution by means of potentiodynamic polarization testing. It was found that the corrosion performance of the films could be enhanced by higher sputtering powers.

Field emission from bias-grown diamond thin films in a microwave plasma

DOEpatents

Gruen, Dieter M.; Krauss, Alan R.; Ding, Ming Q.; Auciello, Orlando

2002-01-01

A method of producing diamond or diamond like films in which a negative bias is established on a substrate with an electrically conductive surface in a microwave plasma chemical vapor deposition system. The atmosphere that is subjected to microwave energy includes a source of carbon, nitrogen and hydrogen. The negative bias is maintained on the substrate through both the nucleation and growth phase of the film until the film is continuous. Biases between -100V and -200 are preferred. Carbon sources may be one or more of CH.sub.4, C.sub.2 H.sub.2 other hydrocarbons and fullerenes.

Electrical resistivity measurements on fragile organic single crystals in the diamond anvil cell

NASA Astrophysics Data System (ADS)

Adachi, T.; Tanaka, H.; Kobayashi, H.; Miyazaki, T.

2001-05-01

A method of sample assembly for four-probe resistivity measurements on fragile organic single crystals using a diamond anvil cell is presented. A procedure to keep insulation between the metal gasket and four leads of thin gold wires bonded to the sample crystal by gold paint is described in detail. The resistivity measurements performed on a single crystal of an organic semiconductor and that of neutral molecules up to 15 GPa and down to 4.2 K showed that this new procedure of four-probe diamond anvil resistivity measurements enables us to obtain sufficiently accurate resistivity data of organic crystals.

Low pressure growth of cubic boron nitride films

NASA Technical Reports Server (NTRS)

Ong, Tiong P. (Inventor); Shing, Yuh-Han (Inventor)

1997-01-01

A method for forming thin films of cubic boron nitride on substrates at low pressures and temperatures. A substrate is first coated with polycrystalline diamond to provide a uniform surface upon which cubic boron nitride can be deposited by chemical vapor deposition. The cubic boron nitride film is useful as a substitute for diamond coatings for a variety of applications in which diamond is not suitable. any tetragonal or hexagonal boron nitride. The cubic boron nitride produced in accordance with the preceding example is particularly well-suited for use as a coating for ultra hard tool bits and abrasives, especially those intended to use in cutting or otherwise fabricating iron.

Scratch-Resistant Lenses

NASA Technical Reports Server (NTRS)

1996-01-01

Lewis Research Center developed a process for achieving diamond- hard coatings for aerospace systems. The technique involves coating the material with a film of diamond-like carbon (DLC) using direct ion deposition. An ion generator creates a stream of ions from a hydrocarbon gas source; the carbon ions impinge directly on the target substrate and 'grow' into a thin DLC film. In 1988, Air Products and Chemicals, Inc. received a license to the NASA patent. Diamonex, an Air Products spinoff company, further developed the NASA process to create the DiamondHard technology used on the Bausch & Lomb Ray- Ban Survivors sunglasses. The sunglasses are scratch-resistant and shed water more easily, thus reducing spotting.

Neurocognitive Functioning in Young Adults with Subclinical Body Dysmorphic Disorder.

PubMed

Blum, Austin W; Redden, Sarah A; Grant, Jon E

2018-03-01

Despite reasonable knowledge of body dysmorphic disorder (BDD), little is known of its cognitive antecedents. In this study, we evaluated executive functioning and decision-making in people at risk of developing BDD using neuropsychological tests. Participants were non-treatment seeking volunteers (18-29 years) recruited from the general community, and split into two groups: those "at risk" of developing BDD (N = 5) and controls (N = 82). Participants undertook the One-Touch Stockings of Cambridge, Cambridge Gamble and Spatial Working Memory tasks and were assessed with the Body Dysmorphic Disorder Questionnaire. Results showed that the at-risk subjects performed significantly worse on a measure of executive function, whereas measures of risk-seeking behavior, quality of decision-making, and spatial working memory were largely intact. The findings suggest that selective cognitive dysfunction may already be present in terms of executive functioning in those at risk of developing BDD, even before psychopathology arises.

Slice them up or slice them out? Legal liability for operating on the troublesome patient in cosmetic surgery.

PubMed

Kennedy, Aileen

2015-09-01

The practice of cosmetic surgery is constructed as psychologically beneficial. This therapeutic promise transforms cosmetic surgery into proper medical treatment. However, there is emerging evidence that a significant percentage of cosmetic surgery patients suffer from the condition of Body Dysmorphic Disorder (BDD), which is characterised by excessive preoccupation with imagined or minor defects in appearance. BDD is uniformly identified as a strong contra-indication for cosmetic surgery. Articles in scholarly journals on cosmetic surgery identify the "red flag" indicators to assist in screening out problem patients. However, a close examination of the most common indicators reveals that most are ineffective in identifying BDD in prospective patients. This article also considers the legal liability of cosmetic surgeons who operate on patients with BDD, and concludes that there is little likelihood of liability in trespass or negligence under current Australia law.

Body Dysmorphic, Obsessive-Compulsive, and Social Anxiety Disorder Beliefs as Predictors of In Vivo Stressor Responding.

PubMed

Parsons, E Marie; Straub, Kelsey T; Smith, April R; Clerkin, Elise M

2017-06-01

This study tested the potential transdiagnostic nature of body dysmorphic disorder (BDD), obsessive-compulsive disorder (OCD), and social anxiety disorder (SAD) beliefs, in addition to testing the specificity of those beliefs, in predicting how individuals responded to symptom-specific stressors. Participants included 127 adults (75% women) with a broad range of symptom severity. Path analysis was used to evaluate whether specific maladaptive beliefs predicted distress in response to symptom-relevant stressors over and above other beliefs and baseline distress. SAD beliefs emerged as a significant predictor of distress in response to a mirror gazing (BDD-relevant), a thought (OCD-relevant), and a public speaking (SAD-relevant) task, controlling for other disorder beliefs and baseline distress. BDD beliefs were also a robust predictor of BDD stressor responding. Results suggest that social anxiety-relevant beliefs may function as a transdiagnostic risk factor that predicts in vivo symptoms across a range of problem areas.

Electrochemical treatment of pharmaceutical wastewater by combining anodic oxidation with ozonation.

PubMed

Menapace, Hannes M; Diaz, Nicolas; Weiss, Stefan

2008-07-01

Wastewater effluents from sewage treatment plants (STP) are important point sources for residues of pharmaceuticals and complexing agents in the aquatic environment. For this reason a research project, which started in December 2006, was established to eliminate pharmaceutical substances and complexing agents found in wastewater as micropollutants. For the treatment process a combination of anodic oxidation by boron-doped diamond (BDD) electrodes and ozonation is examined and presented. For the ozone production a non-conventional, separate reactor was used, in which ozone was generated by electrolysis with diamond electrodes For the determination of the achievable remediation rates four complexing agents (e.g., EDTA, NTA) and eight pharmaceutical substances (e.g., diazepam, carbamazepin) were analyzed in several test runs under different conditions (varied flux, varied current density for the diamond electrode and the ozone producing electrode of the ozone generator, different packing materials for the column in the ozone injection system). The flowrates of the treated water samples were varied from 3 L/h up to 26 L/h. For the anodic oxidation the influence of the current density was examined in the range between 22.7 and 45.5 mA/cm(2), for the ozone producing reactor two densities (1.8 a/cm(2) and 2.0 A/cm(2)) were tested. Matrix effects were investigated by test runs with samples from the effluent of an STP and synthetic waste water. Therefore the impact of the organic material in the samples could be determined by the comparison of the redox potential and the achievable elimination rates of the investigated substances. Comparing both technologies anodic oxidation seems to be superior to ozonation in each investigated area. With the used technology of anodic oxidation elimination rates up to 99% were reached for the investigated pharmaceutical substances at a current density of 45.5 mA/cm(2) and a maximum sample flux of 26 L/h.

Transient current induced in thin film diamonds by swift heavy ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sato, Shin-ichiro; Makino, Takahiro; Ohshima, Takeshi

Single crystal diamond is a suitable material for the next generation particle detectors because of the superior electrical properties and the high radiation tolerance. In order to investigate charge transport properties of diamond particle detectors, transient currents generated in diamonds by single swift heavy ions (26 MeV O 5 + and 45 MeV Si 7 +) are investigated. We also measured two dimensional maps of transient currents by single ion hits. In the case of 50 μm-thick diamond, both the signal height and the collected charge are reduced by the subsequent ion hits and the charge collection time is extended.more » Our results are thought to be attributable to the polarization effect in diamond and it appears only when the transient current is dominated by hole current. In the case of 6 μm-thick diamond membrane, an “island” structure is found in the 2D map of transient currents. Signals in the islands shows different applied bias dependence from signals in other regions, indicating different crystal and/or metal contact quality. Simulation study of transient currents based on the Shockley-Ramo theorem clarifies that accumulation of space charges changes distribution of electric field in diamond and causes the polarization effect.« less

Transient current induced in thin film diamonds by swift heavy ions

DOE PAGES

Sato, Shin-ichiro; Makino, Takahiro; Ohshima, Takeshi; ...

2017-04-05

Single crystal diamond is a suitable material for the next generation particle detectors because of the superior electrical properties and the high radiation tolerance. In order to investigate charge transport properties of diamond particle detectors, transient currents generated in diamonds by single swift heavy ions (26 MeV O 5 + and 45 MeV Si 7 +) are investigated. We also measured two dimensional maps of transient currents by single ion hits. In the case of 50 μm-thick diamond, both the signal height and the collected charge are reduced by the subsequent ion hits and the charge collection time is extended.more » Our results are thought to be attributable to the polarization effect in diamond and it appears only when the transient current is dominated by hole current. In the case of 6 μm-thick diamond membrane, an “island” structure is found in the 2D map of transient currents. Signals in the islands shows different applied bias dependence from signals in other regions, indicating different crystal and/or metal contact quality. Simulation study of transient currents based on the Shockley-Ramo theorem clarifies that accumulation of space charges changes distribution of electric field in diamond and causes the polarization effect.« less

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study

PubMed Central

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-01-01

Introduction Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. Aim To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. Methods An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). Main Outcome Measures The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Results Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Conclusion Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures. PMID:26468378

Sexual Functioning and Behavior of Men with Body Dysmorphic Disorder Concerning Penis Size Compared with Men Anxious about Penis Size and with Controls: A Cohort Study.

PubMed

Veale, David; Miles, Sarah; Read, Julie; Troglia, Andrea; Wylie, Kevan; Muir, Gordon

2015-09-01

Little is known about the sexual functioning and behavior of men anxious about the size of their penis and the means that they might use to try to alter the size of their penis. To compare sexual functioning and behavior in men with body dysmorphic disorder (BDD) concerning penis size and in men with small penis anxiety (SPA without BDD) and in a control group of men who do not have any concerns. An opportunistic sample of 90 men from the community were recruited and divided into three groups: BDD (n = 26); SPA (n = 31) and controls (n = 33). The Index of Erectile Function (IEF), sexual identity and history; and interventions to alter the size of their penis. Men with BDD compared with controls had reduced erectile dysfunction, orgasmic function, intercourse satisfaction and overall satisfaction on the IEF. Men with SPA compared with controls had reduced intercourse satisfaction. There were no differences in sexual desire, the frequency of intercourse or masturbation across any of the three groups. Men with BDD and SPA were more likely than the controls to attempt to alter the shape or size of their penis (for example jelqing, vacuum pumps or stretching devices) with poor reported success. Men with BDD are more likely to have erectile dysfunction and less satisfaction with intercourse than controls but maintain their libido. Further research is required to develop and evaluate a psychological intervention for such men with adequate outcome measures.

Body dysmorphic disorder in aesthetic rhinoplasty candidates.

PubMed

Mr, Fathololoomi; Tabrizi A, Goljanian; Bafghi A, Fattahi; Sa, Noohi; A, Makhdoom

2013-01-01

Body Dysmorphic Disorder (BDD) is a psychiatric disorder defined as obsessive ideas about distorted physical appearance, leading to social, professional and personal dysfunction. Many of these patients seek aesthetic surgery and are generally dissatisfied with the outcome of their surgery. In the present study patients coming to the otolaryngology clinic of Thaleghani Hospital in Tehran seeking rhinoplasty were evaluated. Between October 2010 and October 2011, 130 patients seeking rhinoplasty were recruited in a cross-sectional study. These patients were consecutively interviewed in the otolaryngology clinic of Taleghani Hospital, Tehran, Iran. Questionnaires were filled containing demographic data. BDD was evaluated by a separate questionnaire. Hospital Anxiety and Depression Scale (HADS) questionnaire was filled to evaluate depression and anxiety. Data were analyzed by using SPSS software. The frequency and standard deviations were calculated. Differences between groups were evaluated by using the chi-square, and t-tests. Ninety nine (76.2%) of rhinoplasty candidates were female and thirty one (23.8%) were male. Eighty five (65.4%) were single and thirty eight (29.2%) were married while seven were divorced. About 63.8% were University students or University graduates. Mean age was 26.43±6.29 years old. 41 patients (31.5%) had BDD. Among BDD patients 12 (29.3%) had concurrent depression and 11 (26.8%) had concurrent anxiety. No statistically significant correlation was found between the presence or severity of BDD and age, gender, marital status, level of education and profession. Considering the high prevalence of Body Dysmorphic Disorder (BDD) among rhinoplasty candidates, psychiatric evaluation is advisable before surgery to avoid unnecessary operations and patient dissatisfaction.

Microcrystalline diamond cylindrical resonators with quality-factor up to 0.5 million

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saito, Daisuke; Yang, Chen; Lin, Liwei

2016-02-01

We demonstrate high quality-factor 1.5 mm diameter batch-fabricated microcrystalline diamond cylindrical resonators (CR) with quality-factors limited by thermoelastic damping (TED) and surface loss. Resonators were fabricated 2.6 and 5.3 μm thick in-situ boron-doped microcrystalline diamond films deposited using hot filament chemical vapor deposition. The quality-factor (Q) of as-fabricated CR's was found to increase with the resonator diameter and diamond thickness. Annealing the CRs at 700 °C in a nitrogen atmosphere led to a three-fold increase in Q, a result we attribute to thinning of the diamond layer via reaction with residual O{sub 2} in the annealing furnace. Post-anneal Q exceeding 0.5 million (528 000)more » was measured at the 19 kHz elliptical wineglass modes, producing a ring-down time of 8.9 s. A model for Q versus diamond thickness and resonance frequency is developed including the effects of TED and surface loss. Measured quality factors are shown to agree with the predictions of this model.« less

Fabrication of a nanometer thick nitrogen delta doped layer at the sub-surface region of (100) diamond

NASA Astrophysics Data System (ADS)

Chandran, Maneesh; Michaelson, Shaul; Saguy, Cecile; Hoffman, Alon

2016-11-01

In this letter, we report on the proof of a concept of an innovative delta doping technique to fabricate an ensemble of nitrogen vacancy centers at shallow depths in (100) diamond. A nitrogen delta doped layer with a concentration of ˜1.8 × 1020 cm-3 and a thickness of a few nanometers was produced using this method. Nitrogen delta doping was realized by producing a stable nitrogen terminated (N-terminated) diamond surface using the RF nitridation process and subsequently depositing a thin layer of diamond on the N-terminated diamond surface. The concentration of nitrogen on the N-terminated diamond surface and its stability upon exposure to chemical vapor deposition conditions are determined by x-ray photoelectron spectroscopy analysis. The SIMS profile exhibits a positive concentration gradient of 1.9 nm/decade and a negative gradient of 4.2 nm/decade. The proposed method offers a finer control on the thickness of the delta doped layer than the currently used ion implantation and delta doping techniques.

Transient thermal stress wave and vibrational analyses of a thin diamond crystal for X-ray free-electron lasers under high-repetition-rate operation

DOE PAGES

Yang, Bo; Wang, Songwei; Wu, Juhao

2018-01-01

High-brightness X-ray free-electron lasers (FELs) are perceived as fourth-generation light sources providing unprecedented capabilities for frontier scientific researches in many fields. Thin crystals are important to generate coherent seeds in the self-seeding configuration, provide precise spectral measurements, and split X-ray FEL pulses, etc. In all of these applications a high-intensity X-ray FEL pulse impinges on the thin crystal and deposits a certain amount of heat load, potentially impairing the performance. In the present paper, transient thermal stress wave and vibrational analyses as well as transient thermal analysis are carried out to address the thermomechanical issues for thin diamond crystals, especiallymore » under high-repetition-rate operation of an X-ray FEL. The material properties at elevated temperatures are considered. It is shown that, for a typical FEL pulse depositing tens of microjoules energy over a spot of tens of micrometers in radius, the stress wave emission is completed on the tens of nanoseconds scale. The amount of kinetic energy converted from a FEL pulse can reach up to ~10 nJ depending on the layer thickness. Natural frequencies of a diamond plate are also computed. The potential vibrational amplitude is estimated as a function of frequency. Here, due to the decreasing heat conductivity with increasing temperature, a runaway temperature rise is predicted for high repetition rates where the temperature rises abruptly after ratcheting up to a point of trivial heat damping rate relative to heat deposition rate.« less

Transient thermal stress wave and vibrational analyses of a thin diamond crystal for X-ray free-electron lasers under high-repetition-rate operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Bo; Wang, Songwei; Wu, Juhao

High-brightness X-ray free-electron lasers (FELs) are perceived as fourth-generation light sources providing unprecedented capabilities for frontier scientific researches in many fields. Thin crystals are important to generate coherent seeds in the self-seeding configuration, provide precise spectral measurements, and split X-ray FEL pulses, etc. In all of these applications a high-intensity X-ray FEL pulse impinges on the thin crystal and deposits a certain amount of heat load, potentially impairing the performance. In the present paper, transient thermal stress wave and vibrational analyses as well as transient thermal analysis are carried out to address the thermomechanical issues for thin diamond crystals, especiallymore » under high-repetition-rate operation of an X-ray FEL. The material properties at elevated temperatures are considered. It is shown that, for a typical FEL pulse depositing tens of microjoules energy over a spot of tens of micrometers in radius, the stress wave emission is completed on the tens of nanoseconds scale. The amount of kinetic energy converted from a FEL pulse can reach up to ~10 nJ depending on the layer thickness. Natural frequencies of a diamond plate are also computed. The potential vibrational amplitude is estimated as a function of frequency. Here, due to the decreasing heat conductivity with increasing temperature, a runaway temperature rise is predicted for high repetition rates where the temperature rises abruptly after ratcheting up to a point of trivial heat damping rate relative to heat deposition rate.« less

Transient thermal stress wave and vibrational analyses of a thin diamond crystal for X-ray free-electron lasers under high-repetition-rate operation.

PubMed

Yang, Bo; Wang, Songwei; Wu, Juhao

2018-01-01

High-brightness X-ray free-electron lasers (FELs) are perceived as fourth-generation light sources providing unprecedented capabilities for frontier scientific researches in many fields. Thin crystals are important to generate coherent seeds in the self-seeding configuration, provide precise spectral measurements, and split X-ray FEL pulses, etc. In all of these applications a high-intensity X-ray FEL pulse impinges on the thin crystal and deposits a certain amount of heat load, potentially impairing the performance. In the present paper, transient thermal stress wave and vibrational analyses as well as transient thermal analysis are carried out to address the thermomechanical issues for thin diamond crystals, especially under high-repetition-rate operation of an X-ray FEL. The material properties at elevated temperatures are considered. It is shown that, for a typical FEL pulse depositing tens of microjoules energy over a spot of tens of micrometers in radius, the stress wave emission is completed on the tens of nanoseconds scale. The amount of kinetic energy converted from a FEL pulse can reach up to ∼10 nJ depending on the layer thickness. Natural frequencies of a diamond plate are also computed. The potential vibrational amplitude is estimated as a function of frequency. Due to the decreasing heat conductivity with increasing temperature, a runaway temperature rise is predicted for high repetition rates where the temperature rises abruptly after ratcheting up to a point of trivial heat damping rate relative to heat deposition rate.

Metallurgical coatings and thin films; Proceedings of the International Conference, 18th, San Diego, CA, Apr. 22-26, 1991. Vols. 1 & 2

NASA Technical Reports Server (NTRS)

Mcguire, Gary E. (Editor); Mcintyre, Dale C. (Editor); Hofmann, Siegfried (Editor)

1991-01-01

A conference on metallurgical coatings and thin films produced papers in the areas of coatings for use at high temperatures; hard coatings and deposition technologies; diamonds and related materials; tribological coatings/surface modifications; thin films for microelectronics and high temperature superconductors; optical coatings, film characterization, magneto-optics, and guided waves; and methods for characterizing films and modified surfaces.

Diamond thin film temperature and heat-flux sensors

NASA Technical Reports Server (NTRS)

Aslam, M.; Yang, G. S.; Masood, A.; Fredricks, R.

1995-01-01

Diamond film temperature and heat-flux sensors are developed using a technology compatible with silicon integrated circuit processing. The technology involves diamond nucleation, patterning, doping, and metallization. Multi-sensor test chips were designed and fabricated to study the thermistor behavior. The minimum feature size (device width) for 1st and 2nd generation chips are 160 and 5 micron, respectively. The p-type diamond thermistors on the 1st generation test chip show temperature and response time ranges of 80-1270 K and 0.29-25 microseconds, respectively. An array of diamond thermistors, acting as heat flux sensors, was successfully fabricated on an oxidized Si rod with a diameter of 1 cm. Some problems were encountered in the patterning of the Pt/Ti ohmic contacts on the rod, due mainly to the surface roughness of the diamond film. The use of thermistors with a minimum width of 5 micron (to improve the spatial resolution of measurement) resulted in lithographic problems related to surface roughness of diamond films. We improved the mean surface roughness from 124 nm to 30 nm by using an ultra high nucleation density of 10(exp 11)/sq cm. To deposit thermistors with such small dimensions on a curved surface, a new 3-D diamond patterning technique is currently under development. This involves writing a diamond seed pattern directly on the curved surface by a computer-controlled nozzle.

Structure of thin diamond films: A 1H and 13C nuclear-magnetic-resonance study

NASA Astrophysics Data System (ADS)

Pruski, M.; Lang, D. P.; Hwang, Son-Jong; Jia, H.; Shinar, J.

1994-04-01

The 1H and 13C nuclear magnetic resonance (NMR) of thin diamond films deposited from naturally abundant (1.1 at. %) as well as 50% and 100% 13enriched CH4 heavily diluted in H2 is described and discussed. Less than 0.6 at. % of hydrogen is found in the films which contain crystallites up to ~15 μm across. The 1H NMR consists of a broad 50-65-kHz-wide Gaussian line attributed to H atoms bonded to carbon and covering the crystallite surfaces. A narrow Lorentzian line was only occasionally observed and is found not to be intrinsic to the diamond structure. The 13C NMR demonstrates that >99.5% of the C atoms reside in a quaternary diamondlike configuration. 1-13C cross-polarization measurement indicates that, at the very least, the majority of 13C nuclei cross polarized by 1H, i.e., within three bond distances from a 1H at a crystallite surface, reside in sp3 diamondlike coordinated sites. The 13C relaxation rates of the films are four orders of magnitude faster than that of natural diamond and believed to be due to 13C spin diffusion to paramagnetic centers, presumably carbon dangling bonds. Analysis of the measured relaxation rates indicates that within the 13C spin-diffusion length of √DTc1 ~0.05 μm, these centers are uniformly distributed in the diamond crystallites. The possibility that the dangling bonds are located at internal nanovoid surfaces is discussed.

Developments in FTIR spectroscopy of diamonds and better constraints on diamond thermal histories

NASA Astrophysics Data System (ADS)

Kohn, Simon; Speich, Laura; Smith, Christopher; Bulanova, Galina

2017-04-01

Fourier Transform Infrared (FTIR) spectroscopy is a commonly-used technique for investigating diamonds. It gives the most useful information if spatially-resolved measurements are used [1]. In this contribution we discuss the best way to acquire and present FTIR data from diamonds, using examples from Murowa (Zimbabwe), Argyle (Australia) and Machado River (Brazil). Examples of FTIR core-to-rim line scans, maps with high spatial resolution and maps with high spectral resolution that are fitted to extract the spatial variation of different nitrogen and hydrogen defects are presented. Model mantle residence temperatures are calculated from the concentration of A and B nitrogen-containing defects in the diamonds using known times of annealing in the mantle. A new, two-stage thermal annealing model is presented that better constrains the thermal history of the diamond and that of the mantle lithosphere in which the diamond resided. The effect of heterogeneity within the analysed FTIR volume is quantitatively assessed and errors in model temperatures that can be introduced by studying whole diamonds instead of thin plates are discussed. The kinetics of platelet growth and degradation will be discussed and the potential for two separate, kinetically-controlled defect reactions to be used to constrain a full thermal history of the diamond will be assessed. [1] Kohn, S.C., Speich, L., Smith, C.B. and Bulanova, G.P., 2016. FTIR thermochronometry of natural diamonds: A closer look. Lithos, 265, pp.148-158.

A Solar-Blind UV Detector Based on Graphene-Microcrystalline Diamond Heterojunctions.

PubMed

Wei, Minsong; Yao, Kaiyuan; Liu, Yumeng; Yang, Chen; Zang, Xining; Lin, Liwei

2017-09-01

An ultraviolet detector is demonstrated through a whole-wafer, thin diamond film transfer process to realize the heterojunction between graphene and microcrystalline diamond (MCD). Conventional direct transfer processes fail to deposit graphene onto the top surface of the MCD film. However, it is found that the 2 µm thick MCD diamond film can be easily peeled off from the growth silicon substrate to expose its smooth backside for the graphene transfer process for high-quality graphene/MCD heterojunctions. A vertical graphene/MCD/metal structure is constructed as the photodiode device using graphene as the transparent top electrode for solar-blind ultraviolet sensing with high responsivity and gain factor. As such, this material system and device architecture could serve as the platform for next-generation optoelectronic systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Behavior driven testing in ALMA telescope calibration software

NASA Astrophysics Data System (ADS)

Gil, Juan P.; Garces, Mario; Broguiere, Dominique; Shen, Tzu-Chiang

2016-07-01

ALMA software development cycle includes well defined testing stages that involves developers, testers and scientists. We adapted Behavior Driven Development (BDD) to testing activities applied to Telescope Calibration (TELCAL) software. BDD is an agile technique that encourages communication between roles by defining test cases using natural language to specify features and scenarios, what allows participants to share a common language and provides a high level set of automated tests. This work describes how we implemented and maintain BDD testing for TELCAL, the infrastructure needed to support it and proposals to expand this technique to other subsystems.

Selective MBE growth of hexagonal networks of trapezoidal and triangular GaAs nanowires on patterned (1 1 1)B substrates

NASA Astrophysics Data System (ADS)

Tamai, Isao; Hasegawa, Hideki

2007-04-01

As a combination of novel hardware architecture and novel system architecture for future ultrahigh-density III-V nanodevice LSIs, the authors' group has recently proposed a hexagonal binary decision diagram (BDD) quantum circuit approach where gate-controlled path switching BDD node devices for a single or few electrons are laid out on a hexagonal nanowire network to realize a logic function. In this paper, attempts are made to establish a method to grow highly dense hexagonal nanowire networks for future BDD circuits by selective molecular beam epitaxy (MBE) on (1 1 1)B substrates. The (1 1 1)B orientation is suitable for BDD architecture because of the basic three-fold symmetry of the BDD node device. The growth experiments showed complex evolution of the cross-sectional structures, and it was explained in terms of kinetics determining facet boundaries. Straight arrays of triangular nanowires with 60 nm base width as well as hexagonal arrays of trapezoidal nanowires with a node density of 7.5×10 6 cm -2 were successfully grown with the aid of computer simulation. The result shows feasibility of growing high-density hexagonal networks of GaAs nanowires with precise control of the shape and size.

A systematic review of visual processing and associated treatments in body dysmorphic disorder.

PubMed

Beilharz, F; Castle, D J; Grace, S; Rossell, S L

2017-07-01

Recent advances in body dysmorphic disorder (BDD) have explored abnormal visual processing, yet it is unclear how this relates to treatment. The aim of this study was to summarize our current understanding of visual processing in BDD and review associated treatments. The literature was collected through PsycInfo and PubMed. Visual processing articles were included if written in English after 1970, had a specific BDD group compared to healthy controls and were not case studies. Due to the lack of research regarding treatments associated with visual processing, case studies were included. A number of visual processing abnormalities are present in BDD, including face recognition, emotion identification, aesthetics, object recognition and gestalt processing. Differences to healthy controls include a dominance of detailed local processing over global processing and associated changes in brain activation in visual regions. Perceptual mirror retraining and some forms of self-exposure have demonstrated improved treatment outcomes, but have not been examined in isolation from broader treatments. Despite these abnormalities in perception, particularly concerning face and emotion recognition, few BDD treatments attempt to specifically remediate this. The development of a novel visual training programme which addresses these widespread abnormalities may provide an effective treatment modality. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Metal-induced rapid transformation of diamond into single and multilayer graphene on wafer scale

DOE PAGES

Berman, Diana; Deshmukh, Sanket; Narayanan, Badri; ...

2016-07-04

The degradation of intrinsic properties of graphene during the transfer process constitutes a major challenge in graphene device fabrication, stimulating the need for direct growth of graphene on dielectric substrates. Previous attempts of metal-induced transformation of diamond and silicon carbide into graphene suffers from metal contamination and inability to scale graphene growth over large area. Here in this article, we introduce a direct approach to transform polycrystalline diamond into high-quality graphene layers on wafer scale (4 inch in diameter) using a rapid thermal annealing process facilitated by a nickel, Ni thin film catalyst on top. We show that the processmore » can be tuned to grow single or multilayer graphene with good electronic properties. Molecular dynamics simulations elucidate the mechanism of graphene growth on polycrystalline diamond. Additionally, we demonstrate the lateral growth of free-standing graphene over micron-sized pre-fabricated holes, opening exciting opportunities for future graphene/diamond-based electronics.« less

Metal-induced rapid transformation of diamond into single and multilayer graphene on wafer scale

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berman, Diana; Deshmukh, Sanket; Narayanan, Badri

The degradation of intrinsic properties of graphene during the transfer process constitutes a major challenge in graphene device fabrication, stimulating the need for direct growth of graphene on dielectric substrates. Previous attempts of metal-induced transformation of diamond and silicon carbide into graphene suffers from metal contamination and inability to scale graphene growth over large area. Here in this article, we introduce a direct approach to transform polycrystalline diamond into high-quality graphene layers on wafer scale (4 inch in diameter) using a rapid thermal annealing process facilitated by a nickel, Ni thin film catalyst on top. We show that the processmore » can be tuned to grow single or multilayer graphene with good electronic properties. Molecular dynamics simulations elucidate the mechanism of graphene growth on polycrystalline diamond. Additionally, we demonstrate the lateral growth of free-standing graphene over micron-sized pre-fabricated holes, opening exciting opportunities for future graphene/diamond-based electronics.« less

Effect of absorbing coating on ablation of diamond by IR laser pulses

NASA Astrophysics Data System (ADS)

Kononenko, T. V.; Pivovarov, P. A.; Khomich, A. A.; Khmel'nitskii, R. A.; Konov, V. I.

2018-03-01

We study the possibility of increasing the efficiency and quality of laser ablation microprocessing of diamond by preliminary forming an absorbing layer on its surface. The laser pulses having a duration of 1 ps and 10 ns at a wavelength of 1030 nm irradiate the polycrystalline diamond surface coated by a thin layer of titanium or graphite. We analyse the dynamics of the growth of the crater depth as a function of the number of pulses and the change in optical transmission of the ablated surface. It is found that under irradiation by picosecond pulses the preliminary graphitisation allows one to avoid the laser-induced damage of the internal diamond volume until the appearance of a self-maintained graphitised layer. The absorbing coating (both graphite and titanium) much stronger affects ablation by nanosecond pulses, since it reduces the ablation threshold by more than an order of magnitude and allows full elimination of a laser-induced damage of deep regions of diamond and uncontrolled explosive ablation in the nearsurface layer.

Low-Impedance Compact Modulators Capable of Generating Intense Ultra-fast Rising Nanosecond Waveforms

DTIC Science & Technology

2006-10-31

spark gap is shown in Fig. 1. The Blumleins were constructed from copper plates separated by laminated layered Kapton (polyimide) dielectrics. Scaling... convolution factor. The diamond/GaAs heterojunction response is limited to a very thin layer across the cross section between amorphic diamond and GaAs...were fastened to electrode mounts and passed through the cast material of the base before it hardened. A thick kapton laminate 1.2 cm wide separated

The thermal conductivity of chemical-vapor-deposited diamond films on silicon

NASA Astrophysics Data System (ADS)

Graebner, J. E.; Mucha, J. A.; Seibles, L.; Kammlott, G. W.

1992-04-01

The thermal conductivity of chemical-vapor-deposited diamond films on silicon is measured for the case of heat flow parallel to the plane of the film. A new technique uses thin-film heaters and thermometers on a portion of the film which is made to be free standing by etching away the substrate. Effects of thermal radiation are carefully avoided by choosing the length scale properly. Data for several films yield thermal conductivities in the range 2-6 W/cm C. This is comparable to copper (4 W/cm C) and is in a range that would be useful as a thin-film dielectric material, provided that the interface thermal resistance can be minimized. The conductivity varies inversely with the growth rate and the Raman linewidth.

An Observation of Diamond-Shaped Particle Structure in a Soya Phosphatidylcohline and Bacteriorhodopsin Composite Langmuir Blodgett Film Fabricated by Multilayer Molecular Thin Film Method

NASA Astrophysics Data System (ADS)

Tsujiuchi, Y.; Makino, Y.

A composite film of soya phosphatidylcohline (soya PC) and bacteriorhodopsin (BR) was fabricated by the multilayer molecular thin film method using fatty acid and lipid on a quartz substrate. Direct Force Microscopy (DFM), UV absorption spectra and IR absorption spectra of the film were characterized on the detail of surface structure of the film. The DFM data revealed that many rhombus (diamond-shaped) particles were observed in the film. The spectroscopic data exhibited the yield of M-intermediate of BR in the film. On our modelling of molecular configuration indicate that the coexistence of the strong inter-molecular interaction and the strong inter-molecular interaction between BR trimmers attributed to form the particles.

Diamond X-ray Photodiode for White and Monochromatic SR beams

PubMed Central

Keister, Jeffrey W.; Smedley, John; Muller, Erik M.; Bohon, Jen; Héroux, Annie

2011-01-01

High purity, single crystal CVD diamond plates are screened for quality and instrumented into a sensor assembly for quantitative characterization of flux and position sensitivity. Initial investigations have yielded encouraging results and have led to further development. Several limiting complications are observed and discussed, as well as mitigations thereof. For example, diamond quality requirements for x-ray diodes include low nitrogen impurity and crystallographic defectivity. Thin electrode windows and electronic readout performance are ultimately also critical to device performance. Promising features observed so far from prototype devices include calculable responsivity, flux linearity, position sensitivity and timing performance. Recent results from testing in high flux and high speed applications are described. PMID:21822344

Temperature characteristics of SAW resonators on Sc0.26Al0.74N/polycrystalline diamond heterostructures

NASA Astrophysics Data System (ADS)

Sinusía Lozano, M.; Chen, Z.; Williams, Oliver A.; Iriarte, G. F.

2018-07-01

Surface acoustic wave (SAW) resonators have been fabricated on a 2 μm scandium aluminium nitride (ScAlN) film deposited by means of pulsed-DC reactive magnetron sputtering on a 5.8 μm polycrystalline diamond substrate. Thin film characterization comprised of the assessment of the thin film texture by means of x-ray diffraction (XRD) measurements, reporting highly c-axis oriented ScAlN thin films with a full width at half maximum (FWHM) of the ω-θ scans below 2°. Compositional and piezoelectric analyses of the thin films synthesized with the sputtering parameters used in this work, namely a sputtering power of 700 W and a synthesis pressure of 0.53 Pa, have reported a thin film composition of Sc0.26Al0.74N together with a piezoelectric d33 constant of ‑11 pC/N. Finally, a SAW resonator has been characterized using a vector network analyser (VNA) under various substrate temperature conditions with two iterations. The resulting temperature coefficient of frequency (TCF) values show a highly linear behaviour within two temperature ranges, namely from 20 K to room temperature (300 K) (‑12.5 ppm/K) as well as from 300 K up to 450 K (‑34.6 ppm/K).

Novel phase of carbon, ferromagnetism, and conversion into diamond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayan, Jagdish, E-mail: narayan@ncsu.edu; Bhaumik, Anagh

2015-12-07

We report the discovery of a new phase of carbon (referred to as Q-carbon) and address fundamental issues related to direct conversion of carbon into diamond at ambient temperatures and pressures in air without any need for catalyst and presence of hydrogen. The Q-carbon is formed as result of quenching from super undercooled state by using high-power nanosecond laser pulses. We discuss the equilibrium phase diagram (P vs. T) of carbon and show that by rapid quenching kinetics can shift thermodynamic graphite/diamond/liquid carbon triple point from 5000 K/12 GPa to super undercooled carbon at atmospheric pressure in air. It is shown thatmore » nanosecond laser heating of diamond-like amorphous carbon on sapphire, glass, and polymer substrates can be confined to melt carbon in a super undercooled state. By quenching the carbon from the super undercooled state, we have created a new state of carbon (Q-carbon) from which nanodiamond, microdiamond, microneedles, and single-crystal thin films are formed depending upon the nucleation and growth times allowed for diamond formation. The Q-carbon quenched from liquid is a new state of solid carbon with a higher mass density than amorphous carbon and a mixture of mostly fourfold sp{sup 3} (75%–85%) with the rest being threefold sp{sup 2} bonded carbon (with distinct entropy). It is expected to have new and improved mechanical hardness, electrical conductivity, chemical, and physical properties, including room-temperature ferromagnetism (RTFM) and enhanced field emission. Here we present interesting results on RTFM, enhanced electrical conductivity and surface potential of Q-carbon to emphasize its unique properties. The Q-carbon exhibits robust bulk ferromagnetism with estimated Curie temperature of about 500 K and saturation magnetization value of 20 emu g{sup −1}. From the Q-carbon, diamond phase is nucleated and a variety of micro- and nanostructures and large-area single-crystal diamond sheets are grown by allowing growth times as needed. Subsequent laser pulses can be used to grow nanodiamond into microdiamond and nucleate other nanostructures of diamond on the top of existing microdiamond and create novel nanostructured materials. The microstructural details provide insights into the mechanism of formation of nanodiamond, microdiamond, nanoneedles, microneedles, and single-crystal thin films. This process allows carbon-to-diamond conversion and formation of useful nanostructures and microstructures at ambient temperatures in air at atmospheric pressure on practical and heat-sensitive substrates in a controlled way without need for any catalysts and hydrogen to stabilize sp{sup 3} bonding for diamond formation.« less

Novel phase of carbon, ferromagnetism, and conversion into diamond

NASA Astrophysics Data System (ADS)

Narayan, Jagdish; Bhaumik, Anagh

2015-12-01

We report the discovery of a new phase of carbon (referred to as Q-carbon) and address fundamental issues related to direct conversion of carbon into diamond at ambient temperatures and pressures in air without any need for catalyst and presence of hydrogen. The Q-carbon is formed as result of quenching from super undercooled state by using high-power nanosecond laser pulses. We discuss the equilibrium phase diagram (P vs. T) of carbon and show that by rapid quenching kinetics can shift thermodynamic graphite/diamond/liquid carbon triple point from 5000 K/12 GPa to super undercooled carbon at atmospheric pressure in air. It is shown that nanosecond laser heating of diamond-like amorphous carbon on sapphire, glass, and polymer substrates can be confined to melt carbon in a super undercooled state. By quenching the carbon from the super undercooled state, we have created a new state of carbon (Q-carbon) from which nanodiamond, microdiamond, microneedles, and single-crystal thin films are formed depending upon the nucleation and growth times allowed for diamond formation. The Q-carbon quenched from liquid is a new state of solid carbon with a higher mass density than amorphous carbon and a mixture of mostly fourfold sp3 (75%-85%) with the rest being threefold sp2 bonded carbon (with distinct entropy). It is expected to have new and improved mechanical hardness, electrical conductivity, chemical, and physical properties, including room-temperature ferromagnetism (RTFM) and enhanced field emission. Here we present interesting results on RTFM, enhanced electrical conductivity and surface potential of Q-carbon to emphasize its unique properties. The Q-carbon exhibits robust bulk ferromagnetism with estimated Curie temperature of about 500 K and saturation magnetization value of 20 emu g-1. From the Q-carbon, diamond phase is nucleated and a variety of micro- and nanostructures and large-area single-crystal diamond sheets are grown by allowing growth times as needed. Subsequent laser pulses can be used to grow nanodiamond into microdiamond and nucleate other nanostructures of diamond on the top of existing microdiamond and create novel nanostructured materials. The microstructural details provide insights into the mechanism of formation of nanodiamond, microdiamond, nanoneedles, microneedles, and single-crystal thin films. This process allows carbon-to-diamond conversion and formation of useful nanostructures and microstructures at ambient temperatures in air at atmospheric pressure on practical and heat-sensitive substrates in a controlled way without need for any catalysts and hydrogen to stabilize sp3 bonding for diamond formation.

Evaluation of Relationship Between Body Dysmorphic Disorder and Self-Esteem in Rhinoplasty Candidates.

PubMed

Baykal, Bahadir; Erdim, Ibrahim; Ozbay, Isa; Oghan, Fatih; Oncu, Fatih; Erdogdu, Zeynep; Kayhan, Fatma Tulin

2015-11-01

To investigate the relationship between body dysmorphic syndrome and self-esteem in rhinoplasty candidates. A negative statistical correlation was evident between Rosenberg Self-Esteem Scale (RSES) and Body Dysmorphic Disorder Examination-Self Report (BDDE-SR) scores. In terms of responses to the first Body Dysmorphic Disorder Questionnaire (BDDQ) question, which focuses on general attitude toward body dysmorphic syndrome, the average RSES "YES" score was significantly less than the "NO" score. No significant differences appeared between RSES scores and scores for the 4th subgroup of BDDQ questions (subgroups A, B, and C; these questions explore how much time is spent daily on maintenance of bodily appearance). However, significant differences appeared between scores for the 4th subgroup of BDDQ questions and BDDE-SR scores. The average BDD-SR score of subgroup A (less than 1 hour spent on bodily maintenance) was significantly lower than those of group B (1-3 hours) and group C (more than 3 hours). However, no significant differences appeared in average BDD-SR scores between subgroups B and C. In this prospective study, 56 patients (31 females and 25 males) were evaluated preoperatively using the BDDQ, the BDDE-SR, and the RSES. Patients younger than 15 years and those with deformities caused by trauma were excluded. Rhinoplasty candidates had higher levels of body dysmorphic disorder (BDD). Although patients with low RSES scores were more likely to have BDD, rhinoplasty candidates were not notably deficient in self-esteem. However, in rhinoplasty candidates with low RSES scores, the frequency of BDD was elevated. Therefore, the authors suggest that rhinoplasty candidates with low RSES scores should be investigated carefully in terms of BDD.

Appearance evaluation of others' faces and bodies in anorexia nervosa and body dysmorphic disorder.

PubMed

Moody, Teena D; Shen, Vivian W; Hutcheson, Nathan L; Henretty, Jennifer R; Sheen, Courtney L; Strober, Michael; Feusner, Jamie D

2017-02-01

Individuals with anorexia nervosa (AN) and body dysmorphic disorder (BDD) exhibit distorted perception and negative evaluations of their own appearance; however, little is known about how they perceive others' appearance, and whether or not the conditions share perceptual distortions. Thirty participants with BDD, 22 with AN, now weight-restored, and 39 healthy comparison participants (HC) rated photographs of others' faces and bodies on attractiveness, how overweight or underweight they were, and how much photographs triggered thoughts of their own appearance. We compared responses among groups by stimulus type and by level-of-detail (spatial frequency). Compared to HCs, AN and BDD had lower attractiveness ratings for others' bodies and faces for high-detail and low-detail images, rated bodies as more overweight, and were more triggered to think of their own appearance for faces and bodies. In AN, symptom severity was associated with greater triggering of thoughts of own appearance and higher endorsement of overweight ratings for bodies. In BDD, symptom severity was associated with greater triggering of thoughts of own appearance for bodies and higher overweight ratings for low-detail images. BDD was more triggered to think of own facial appearance than AN. AN and BDD show similar behavioral phenotypes of negative appearance evaluations for others' faces and bodies, and have thoughts of their own appearance triggered even for images outside of their primary appearance concerns, suggesting a more complex cross-disorder body-image phenotype than previously assumed. Future treatment strategies may benefit from addressing how these individuals evaluate others in addition to themselves. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:127-138). © 2016 Wiley Periodicals, Inc.

Protection of rats against 3-butene-1,2-diol-induced hepatotoxicity and hypoglycemia by N-acetyl-L-cysteine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprague, Christopher L.; Elfarra, Adnan A.

2005-09-15

3-Butene-1,2-diol (BDD), an allylic alcohol and major metabolite of 1,3-butadiene, has previously been shown to cause hepatotoxicity and hypoglycemia in male Sprague-Dawley rats, but the mechanisms of toxicity were unclear. In this study, rats were administered BDD (250 mg/kg) or saline, ip, and serum insulin levels, hepatic lactate levels, and hepatic cellular and mitochondrial GSH, GSSG, ATP, and ADP levels were measured 1 or 4 h after treatment. The results show that serum insulin levels were not causing the hypoglycemia and that the hypoglycemia was not caused by an enhancement of the metabolism of pyruvate to lactate because hepatic lactatemore » levels were either similar (1 h) or lower (4 h) than controls. However, both hepatic cellular and mitochondrial GSH and GSSG levels were severely depleted 1 and 4 h after treatment and the mitochondrial ATP/ADP ratio was also lowered 4 h after treatment relative to controls. Because these results suggested a role for hepatic cellular and mitochondrial GSH in BDD toxicity, additional rats were administered N-acetyl-L-cysteine (NAC; 200 mg/kg) 15 min after BDD administration. NAC treatment partially prevented depletion of hepatic cellular and mitochondrial GSH and preserved the mitochondrial ATP/ADP ratio. NAC also prevented the severe depletion of serum glucose concentration and the elevation of serum alanine aminotransferase activity after BDD treatment without affecting the plasma concentration of BDD. Thus, depletion of hepatic cellular and mitochondrial GSH followed by the decrease in the mitochondrial ATP/ADP ratio was likely contributing to the mechanisms of hepatotoxicity and hypoglycemia in the rat.« less

Physical and Tribological Characteristics of Ion-Implanted Diamond Films

NASA Technical Reports Server (NTRS)

Miyoshi, K.; Heidger, S.; Korenyi-Both, A. L.; Jayne, D. T.; Herrera-Fierro, P.; Shogrin, B.; Wilbur, P. J.; Wu, R. L. C.; Garscadden, A.; Barnes, P. N.

1994-01-01

Unidirectional sliding friction experiments were conducted with a natural, polished diamond pin in contact with both as-deposited and carbon-ion-implanted diamond films in ultrahigh vacuum. Diamond films were deposited on silicon, silicon carbide, and silicon nitride by microwave-plasma-assisted chemical vapor deposition. The as-deposited diamond films were impacted with carbon ions at an accelerating energy of 60 keV and a current density of 50 micron A/cm(exp 2) for approximately 6 min, resulting in a dose of 1.2 x 10(exp 17) carbon ions/cm(exp 2). The results indicate that the carbon ion implantation produced a thin surface layer of amorphous, nondiamond carbon. The nondiamond carbon greatly decreased both friction and wear of the diamond films. The coefficients of friction for the carbon-ion-implanted, fine-grain diamond films were less than 0.1, factors of 20 to 30 lower than those for the as-deposited, fine-grain diamond films. The coefficients of friction for the carbon-ion-implanted, coarse-grain diamond films were approximately 0.35, a factor of five lower than those for the as-deposited, coarse-grain diamond films. The wear rates for the carbon-ion-implanted, diamond films were on the order of 10(exp -6) mm(exp 3)/Nm, factors of 30 to 80 lower than that for the as-deposited diamond films, regardless of grain size. The friction of the carbon-ion-implanted diamond films was greatly reduced because the amorphous, nondiamond carbon, which had a low shear strength, was restricted to the surface layers (less than 0.1 micron thick) and because the underlying diamond materials retained their high hardness. In conclusion, the carbon-ion-implanted, fine-grain diamond films can be used effectively as wear resistant, self-lubricating coatings for ceramics, such as silicon nitride and silicon carbide, in ultrahigh vacuum.

Brain connectome modularity in weight-restored anorexia nervosa and body dysmorphic disorder

PubMed Central

Zhang, A; Leow, A; Zhan, L; GadElkarim, J; Moody, T; Khalsa, S; Strober, M; Feusner, JD

2017-01-01

Background Anorexia nervosa (AN) and body dysmorphic disorder (BDD) frequently co-occur, and have several overlapping phenomenological features. Little is known about their shared neurobiology. Aims To compare modular organization of brain structural connectivity. Methods We acquired diffusion-weighted magnetic resonance imaging data on unmedicated individuals with BDD (n=29), weight-restored AN (n=24), and healthy controls (HC) (n=31). We constructed connectivity matrices using whole-brain white matter tractography, and compared modular structures across groups. Results AN showed abnormal modularity involving frontal, basal ganglia, and posterior cingulate nodes. There was a trend in BDD for similar abnormalities, but no significant differences compared with AN. In AN, poor insight correlated with longer path length in right caudal anterior cingulate and right posterior cingulate. Conclusions Abnormal network organization patterns in AN, partially shared with BDD, may have implications for understanding integration between reward and habit/ritual formation, as well as conflict monitoring/error detection. PMID:27429183

Body dysmorphia, self-mutilation and the reconstructive surgeon.

PubMed

Chan, James Kwok-Kwan; Jones, Sophie M; Heywood, Anthony J

2011-01-01

Body dysmorphic disorder (BDD) is a disabling preoccupation with a slight or an imagined defect in appearance. It is recognised in some patients who present to the plastic surgeon requesting multiple cosmetic procedures. Very rarely, BDD patients may wish for amputation of a healthy limb and may even mutilate themselves deliberately in order to necessitate amputation. These patients pose a diagnostic challenge as BDD is uncommon and they are often uncooperative whilst appearing mentally sound. Furthermore, they raise difficult ethical and legal issues for the surgeon. Although there is some guidance for the management of BDD patients seeking elective amputation, there is currently none for the management of those who present in the emergency setting. Illustrated by the case of a man who, having failed to find a complicit surgeon, attempted self-amputation of the hand, we review the relevant ethical, legal and management issues with advice by the British Medical Association and General Medical Council. Copyright © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

[Body dysmorphic disorder: clinical aspects, nosological dimensions and controversies with anorexia nervosa].

PubMed

Behar, Rosa; Arancibia, Marcelo; Heitzer, Cristóbal; Meza, Nicolás

2016-05-01

There is strong evidence about the co-existence of body dysmorphic disorder (BDD) and eating disorders (ED), particularly with anorexia nervosa (AN). An exhaustive review of the specialised literature regarding these disorders was carried out. The results show that their co-occurrence implies a more complex diagnosis and treatment, a more severe clinical symptomatology and a worse prognosis and outcome. Both disorders display common similarities, differences and comorbidities, which allow authors to classify them in different nosological spectra (somatomorphic, anxious, obsessive-compulsive, affective and psychotic). Their crossover involves higher levels of body dissatisfaction and body image distortion, depression, suicidal tendency, personality disorders, substance use/abuse, obsessive-compulsive disorder, social phobia, alexithymia and childhood abuse or neglect background. Treatment including cognitive-behavioral psychotherapy and selective reuptake serotonin inhibitors are effective for both, BDD and ED; nevertheless, plastic surgery could exacerbate BDD. Clinical traits of BDD must be systematically detected in patients suffering from ED and vice versa.

Cometary particles - Thin sectioning and electron beam analysis

NASA Technical Reports Server (NTRS)

Bradley, J. P.; Brownlee, D. E.

1986-01-01

Thin sections (500 to 1000 angstroms thick) of individual micrometeorites (5 to 15 micrometers) have been prepared with an ultramicrotome equipped with a diamond knife. Electron microscope examination of these sections has revealed the internal structures of chondritic micrometeorites, and a subset of highly porous, fragile particles has been identified. Delicate meteoritic materials such as these are characteristic of debris from cometary meteors.

Surface functionalization of thin-film diamond for highly stable and selective biological interfaces

PubMed Central

Stavis, Courtney; Clare, Tami Lasseter; Butler, James E.; Radadia, Adarsh D.; Carr, Rogan; Zeng, Hongjun; King, William P.; Carlisle, John A.; Aksimentiev, Aleksei; Bashir, Rashid; Hamers, Robert J.

2011-01-01

Carbon is an extremely versatile family of materials with a wide range of mechanical, optical, and mechanical properties, but many similarities in surface chemistry. As one of the most chemically stable materials known, carbon provides an outstanding platform for the development of highly tunable molecular and biomolecular interfaces. Photochemical grafting of alkenes has emerged as an attractive method for functionalizing surfaces of diamond, but many aspects of the surface chemistry and impact on biological recognition processes remain unexplored. Here we report investigations of the interaction of functionalized diamond surfaces with proteins and biological cells using X-ray photoelectron spectroscopy (XPS), atomic force microscopy, and fluorescence methods. XPS data show that functionalization of diamond with short ethylene glycol oligomers reduces the nonspecific binding of fibrinogen below the detection limit of XPS, estimated as > 97% reduction over H-terminated diamond. Measurements of different forms of diamond with different roughness are used to explore the influence of roughness on nonspecific binding onto H-terminated and ethylene glycol (EG)-terminated surfaces. Finally, we use XPS to characterize the chemical stability of Escherichia coli K12 antibodies on the surfaces of diamond and amine-functionalized glass. Our results show that antibody-modified diamond surfaces exhibit increased stability in XPS and that this is accompanied by retention of biological activity in cell-capture measurements. Our results demonstrate that surface chemistry on diamond and other carbon-based materials provides an excellent platform for biomolecular interfaces with high stability and high selectivity. PMID:20884854

Hybrid photonic crystal cavity and waveguide for coupling to diamond NV-centers.

PubMed

Barclay, Paul E; Fu, Kai-Mei; Santori, Charles; Beausoleil, Raymond G

2009-06-08

A design for an ultra-high Q photonic crystal nanocavity engineered to interact with nitrogen-vacancy (NV) centers located near the surface of a single crystal diamond sample is presented. The structure is based upon a nanowire photonic crystal geometry, and consists of a patterned high refractive index thin film, such as gallium phosphide (GaP), supported by a diamond substrate. The nanocavity supports a mode with quality factor Q > 1.5 x 10(6) and mode volume V < 0.52(lambda/nGaP)(3), and promises to allow Purcell enhanced collection of spontaneous emission from an NV located more than 50 nm below the diamond surface. The nanowire photonic crystal waveguide can be used to efficiently couple light into and out of the cavity, or as an efficient broadband collector of NV phonon sideband emission. The proposed structures can be fabricated using existing materials and processing techniques.

Single crystal CVD diamond membranes for betavoltaic cells

NASA Astrophysics Data System (ADS)

Delfaure, C.; Pomorski, M.; de Sanoit, J.; Bergonzo, P.; Saada, S.

2016-06-01

A single crystal diamond large area thin membrane was assembled as a p-doped/Intrinsic/Metal (PIM) structure and used in a betavoltaic configuration. When tested with a 20 keV electron beam from a high resolution scanning electron microscope, we measured an open circuit voltage (Voc) of 1.85 V, a charge collection efficiency (CCE) of 98%, a fill-factor of 80%, and a total conversion efficiency of 9.4%. These parameters are inherently linked to the diamond membrane PIM structure that allows full device depletion even at 0 V and are among the highest reported up to now for any other material tested for betavoltaic devices. It enables to drive a high short-circuit current Isc up to 7.12 μA, to reach a maximum power Pmax of 10.48 μW, a remarkable value demonstrating the high-benefit of diamond for the realization of long-life radioisotope based micro-batteries.

Method to grow carbon thin films consisting entirely of diamond grains 3-5 nm in size and high-energy grain boundaries

DOEpatents

Carlisle, John A.; Auciello, Orlando; Birrell, James

2006-10-31

An ultrananocrystalline diamond (UNCD) having an average grain size between 3 and 5 nanometers (nm) with not more than about 8% by volume diamond having an average grain size larger than 10 nm. A method of manufacturing UNCD film is also disclosed in which a vapor of acetylene and hydrogen in an inert gas other than He wherein the volume ratio of acetylene to hydrogen is greater than 0.35 and less than 0.85, with the balance being an inert gas, is subjected to a suitable amount of energy to fragment at least some of the acetylene to form a UNCD film having an average grain size of 3 to 5 nm with not more than about 8% by volume diamond having an average grain size larger than 10 nm.

Status of diamond particle detectors

NASA Astrophysics Data System (ADS)

Krammer, M.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fish, D.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knöpfle, K. T.; Manfredi, P. F.; Meier, D.; Mishina, M.; LeNormand, F.; Pan, L. S.; Pernegger, H.; Pernicka, M.; Re, V.; Riester, G. L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.

1998-11-01

To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given.

Cognitive-Behavioral Therapy for Adolescent Body Dysmorphic Disorder

ERIC Educational Resources Information Center

Greenberg, Jennifer L.; Markowitz, Sarah; Petronko, Michael R.; Taylor, Caitlin E.; Wilhelm, Sabine; Wilson, G. Terence

2010-01-01

The onset of appearance-related concerns associated with body dysmorphic disorder (BDD) typically occurs in adolescence, and these concerns are often severe enough to interfere with normal development and psychosocial functioning. Cognitive behavioral therapy (CBT) is an effective treatment for adults with BDD. However, no treatment studies…

Modular Integrated Stackable Layers (MISL) MI_MSP430A Board Design Document (BDD)

NASA Technical Reports Server (NTRS)

Yim, Hester

2013-01-01

This is a board-level design document for Modular Integrated Stackable Layers (MISL) MI_MSP430A board (PIN MSP430F5438A). The Board Design Document (BDD) contains the description, features of microcontroller, electrical and mechanical design, and drawings.

Thermal Management Investigations in Ceramic Thin Disk Lasers

DTIC Science & Technology

2011-01-14

techniques. 10-14mm diameter 0.2mm thick disks are mounted on silicon carbide ( SiC ), sapphire, and diamond submounts. From a larger platform, more than 6kW...along with various cooling techniques. 10-14mm diameter O.2mm thick disks are mounted on silicon carbide ( SiC ), sapphire, and diamond submounts. From a...assemblies are either attached to heat sinks or directly to the Cu W cooling mount, see Fig. I (c) & (d). The heat sinks tested are SiC , sapphire, and

A psychometric evaluation of the clinician-rated Quick Inventory of Depressive Symptomatology (QIDS-C16) in patients with bipolar disorder.

PubMed

Bernstein, Ira H; Rush, A John; Suppes, Trisha; Trivedi, Madhukar H; Woo, Ada; Kyutoku, Yasushi; Crismon, M Lynn; Dennehy, Ellen; Carmody, Thomas J

2009-06-01

The clinician-rated, 16-item Quick Inventory of Depressive Symptomatology (QIDS-C16) has been extensively evaluated in patients with major depressive disorder (MDD). This report assesses the psychometric properties of the QIDS-C16 in outpatients with bipolar disorder (BD, N = 405) and MDD (N = 547) and in bipolar patients in the depressed phase only (BD-D) (N = 99) enrolled in the Texas Medication Algorithm Project (TMAP) using classical test theory (CTT) and the Samejima graded item response theory (IRT) model. Values of coefficient alpha were very similar in BD, MDD, and BD-D groups at baseline (alpha = 0.80-0.81) and at exit (alpha = 0.82-0.85). The QIDS-C16 was unidimensional for all three groups. MDD and BD-D patients (n = 99) had comparable symptom levels. The BD-D patients (n = 99) had the most, and bipolar patients in the manic phase had the least depressive symptoms at baseline. IRT analyses indicated that the QIDS-C16 was most sensitive to the measurement of depression for both MDD patients and for BD-D patients in the average range. The QIDS-C16 is suitable for use with patients with BD and can be used as an outcome measure in trials enrolling both BD and MDD patients. John Wiley & Sons, Ltd

The Victor Mine (Superior Craton, Canada): Neoproterozoic lherzolitic diamonds from a thermally-modified cratonic root

NASA Astrophysics Data System (ADS)

Stachel, Thomas; Banas, Anetta; Aulbach, Sonja; Smit, Karen V.; Wescott, Pamela; Chinn, Ingrid L.; Kong, Julie

2018-05-01

The Jurassic Victor kimberlite (Attawapiskat Field) was emplaced into an area of the central Superior Craton that was affected by a lithosphere-scale thermal event at 1.1 Ga. Victor diamonds formed ca. 400 million years after this event, in a lithospheric mantle characterized by an unusually cool model geotherm (37-38 mW/m2; Hasterok and Chapman 2011). The bulk of Victor diamonds derives from a thin (<10 km thick) layer that is located at about 180 km depth and represents lherzolitic substrates (for 85% of diamonds). Geothermobarometric calculations (average pressure and temperature at the 1 sigma level are 57 ± 2 kbar and 1129 ± 16 °C) coupled with typical fluid metasomatism-associated trace element patterns for garnet inclusions indicate diamond precipitation under sub-solidus (lherzolite + H2O) conditions. This conclusion links the presence of a diamond-rich lherzolitic layer in the lithospheric mantle, just above the depth where ascending melts would freeze, to the unusually low paleogeotherm beneath Attawapiskat, because along an average cratonic geotherm (40 mW/m2) lherzolite in the presence of hydrous fluid would melt at depths >140 km.

Diamond nanoparticles as a support for Pt and PtRu catalysts for direct methanol fuel cells.

PubMed

La-Torre-Riveros, Lyda; Guzman-Blas, Rolando; Méndez-Torres, Adrián E; Prelas, Mark; Tryk, Donald A; Cabrera, Carlos R

2012-02-01

Diamond in nanoparticle form is a promising material that can be used as a robust and chemically stable catalyst support in fuel cells. It has been studied and characterized physically and electrochemically, in its thin film and powder forms, as reported in the literature. In the present work, the electrochemical properties of undoped and boron-doped diamond nanoparticle electrodes, fabricated using the ink-paste method, were investigated. Methanol oxidation experiments were carried out in both half-cell and full fuel cell modes. Platinum and ruthenium nanoparticles were chemically deposited on undoped and boron doped diamond nanoparticles through the use of NaBH(4) as reducing agent and sodium dodecyl benzene sulfonate (SDBS) as a surfactant. Before and after the reduction process, samples were characterized by electron microscopy and spectroscopic techniques. The ink-paste method was also used to prepare the membrane electrode assembly with Pt and Pt-Ru modified undoped and boron-doped diamond nanoparticle catalytic systems, to perform the electrochemical experiments in a direct methanol fuel cell system. The results obtained demonstrate that diamond supported catalyst nanomaterials are promising for methanol fuel cells.

Preface: phys. stat. sol. (a) 202/11

NASA Astrophysics Data System (ADS)

Bergonzo, Philippe; Nesládek, Milo

2005-09-01

The present issue of physica status solidi (a) contains a collection of 31 papers presented at the 10th International Workshop on Surface and Bulk Defects in CVD Diamond Films held in Diepenbeek-Hasselt, Belgium, 23-25 February 2005. The 10th anniversary of the meeting proved the success of the concept, which originated in 1996 with the idea of bringing together scientists who are active and innovative in the field of electronic and optical properties of thin film diamond. This year the programme contained 9 invited oral talks, 14 contributed oral talks and 34 posters. 103 Participants from 14 countries (Austria, Belgium, Czech Republic, Finland, France, Germany, Japan, Mexico, Poland, Slovak Republic, Sweden, Switzerland, UK, USA) took part in the meeting. The meeting was traditionally directed towards topics ranging from defects and their characterization as well as electrical transport in CVD diamond towards modern diamond thin film devices including bio-sensing applications. Also, diamond homoepitaxial and heteroepitaxial growth, doping, hydrogen induced surface conductivity and several other topics including defects in boron nitride materials were addressed. Intense and lively discussions were as usual part of this meeting to which the hospitality of the city of Hasselt contributed greatly.The workshop would have not been possible without the support of many people and institutions. We also acknowledge the financial support of the Scientific Research Community of the F.W.O.-Vlaanderen (Belgium) and the University of Hasselt. We also thank the editorial staff of physica status solidi, most notably Stefan Hildebrandt, for their excellent and patient work. Finally, we would like to thank Ken Haenen, whose skills for the successful organization are gratefully acknowledged.August 2005

Efficient electrochemical degradation of multiwall carbon nanotubes.

PubMed

Reipa, Vytas; Hanna, Shannon K; Urbas, Aaron; Sander, Lane; Elliott, John; Conny, Joseph; Petersen, Elijah J

2018-07-15

As the production mass of multiwall carbon nanotubes (MWCNT) increases, the potential for human and environmental exposure to MWCNTs may also increase. We have shown that exposing an aqueous suspension of pristine MWCNTs to an intense oxidative treatment in an electrochemical reactor, equipped with an efficient hydroxyl radical generating Boron Doped Diamond (BDD) anode, leads to their almost complete mineralization. Thermal optical transmittance analysis showed a total carbon mass loss of over two orders of magnitude due to the electrochemical treatment, a result consistent with measurements of the degraded MWCNT suspensions using UV-vis absorbance. Liquid chromatography data excludes substantial accumulation of the low molecular weight reaction products. Therefore, up to 99% of the initially suspended MWCNT mass is completely mineralized into gaseous products such as CO 2 and volatile organic carbon. Scanning electron microscopy (SEM) images show sporadic opaque carbon clusters suggesting the remaining nanotubes are transformed into structure-less carbon during their electrochemical mineralization. Environmental toxicity of pristine and degraded MWCNTs was assessed using Caenorhabditis elegans nematodes and revealed a major reduction in the MWCNT toxicity after treatment in the electrochemical flow-by reactor. Published by Elsevier B.V.

Electrochemistry coupled online to liquid chromatography-mass spectrometry for fast simulation of biotransformation reactions of the insecticide chlorpyrifos.

PubMed

Mekonnen, Tessema F; Panne, Ulrich; Koch, Matthias

2017-05-01

An automated method is presented for fast simulation of (bio)transformation products (TPs) of the organophosphate insecticide chlorpyrifos (CPF) based on electrochemistry coupled online to liquid chromatography-mass spectrometry (EC-LC-MS). Oxidative TPs were produced by a boron doped diamond (BDD) electrode, separated by reversed phase HPLC and online detected by electrospray ionization-mass spectrometry (ESI-MS). Furthermore, EC oxidative TPs were investigated by HPLC-tandem mass spectrometry (LC-MS/MS) and FT-ICR high resolution mass spectrometry (HRMS) and compared to in vitro assay metabolites (rat and human liver microsomes). Main phase I metabolites of CPF: chlorpyrifos oxon (CPF oxon), trichloropyridinol (TCP), diethylthiophosphate (DETP), diethylphosphate (DEP), desethyl chlorpyrifos (De-CPF), and desethyl chlorpyrifos oxon (De-CPF oxon), were successfully identified by the developed EC-LC-MS method. The EC-LC-MS method showed similar metabolites compared to the in vitro assay with possibilities of determining reactive species. Our results reveal that online EC-(LC)-MS brings an advantage on time of analysis by eliminating sample preparation steps and matrix complexity compared to conventional in vivo or in vitro methods.

Electrochemical degradation of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in groundwater.

PubMed

Trautmann, A M; Schell, H; Schmidt, K R; Mangold, K-M; Tiehm, A

2015-01-01

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) represent hazardous pollutants and are frequently detected in the environment, e.g. in contaminated groundwater. PFASs are persistent to biodegradation and conventional oxidation processes such as ozonation. In this study electrochemical degradation of PFASs on boron-doped diamond (BDD) electrodes is demonstrated. Experiments were performed with model solutions and contaminated groundwater with a dissolved organic carbon (DOC) content of 13 mg/L. The perfluorinated carboxylic acids (PFCAs) perfluorobutanoate, perfluoropentanoate, perfluorohexanoate, perfluoroheptanoate and perfluorooctanoate, and the perfluorinated sulfonic acids (PFSAs) perfluorobutane sulfonate, perfluorohexane sulfonate, perfluorooctane sulfonate and 6:2 fluorotelomer sulfonate were detected in the groundwater samples. At PFAS concentrations ranging from 0.26 to 34 mg/L (0.7 to 79 μM), the degradation of PFASs was achieved despite of the high DOC background. Pseudo first-order kinetic constants of PFSA degradation increased with the increase of carbon chain length. Fluoride formation as well as the generation of PFCAs with shortened chain lengths was observed. Inorganic byproducts such as perchlorate were also formed and have to be considered in further process optimization.

Optimization of the electrochemical degradation process of the antibiotic ciprofloxacin using a double-sided β-PbO2 anode in a flow reactor: kinetics, identification of oxidation intermediates and toxicity evaluation.

PubMed

Wachter, Naihara; Aquino, José M; Denadai, Marina; Barreiro, Juliana C; Silva, Adilson J; Cass, Quezia B; Rocha-Filho, Romeu C; Bocchi, Nerilso

2018-06-06

The electrochemical degradation of ciprofloxacin-CIP (50 mg L -1 in 0.10 mol L -1 Na 2 SO 4 ) was investigated using a double-sided Ti-Pt/β-PbO 2 anode in a filter-press flow reactor, with identification of oxidation intermediates and follow-up of antimicrobial activity against Escherichia coli. The effect of solution pH, flow rate, current density, and temperature on the CIP removal rate was evaluated. All of these parameters did affect the CIP removal performance; thus, optimized electrolysis conditions were further explored: pH = 10, q V  = 6.5 L min -1 , j = 30 mA cm -2 , and θ = 25 °C. Therefore, CIP was removed within 2 h, whereas ~75% of the total organic carbon concentration (TOC) was removed after 5 h and then, the solution no longer presented antimicrobial activity. When the electrochemical degradation of CIP was investigated using a single-sided boron-doped diamond (BDD) anode, its performance in TOC removal was similar to that of the Ti-Pt/β-PbO 2 anode; considering the higher oxidation power of BDD, the surprisingly good comparative performance of the Ti-Pt/β-PbO 2 anode was ascribed to significantly better hydrodynamic conditions attained in the filter-press reactor used with this electrode. Five initial oxidation intermediates were identified by LC-MS/MS and completely removed after 4 h of electrolysis; since they have also been determined in other degradation processes, there must be similarities in the involved oxidation mechanisms. Five terminal oxidation intermediates (acetic, formic, oxamic, propionic, and succinic acids) were identified by LC-UV and all of them (except acetic acid) were removed after 10 h of electrolysis.

Prevalence of Body Dysmorphic Disorder Symptoms and Associated Clinical Features among Australian University Students

ERIC Educational Resources Information Center

Bartsch, Dianna

2007-01-01

The current study addressed the frequency of body dysmorphic disorder (BDD) symptoms among university students and investigated the predictors of dysmorphic concern. Six hundred and nineteen Australian university students completed measures assessing BDD, dysmorphic concern, self-esteem, depression, life satisfaction, self-oriented and socially…

Modular Cognitive-Behavioral Therapy for Body Dysmorphic Disorder

ERIC Educational Resources Information Center

Wilhelm, Sabine; Phillips, Katharine A.; Fama, Jeanne M.; Greenberg, Jennifer L.; Steketee, Gail

2011-01-01

This study pilot tested a newly developed modular cognitive-behavioral therapy (CBT) treatment manual for body dysmorphic disorder (BDD). We tested feasibility, acceptability, and treatment outcome in a sample of 12 adults with primary BDD. Treatment was delivered in weekly individual sessions over 18 or 22 weeks. Standardized clinician ratings…

Effect of working pressure on corrosion behavior of nitrogen doped diamond-like carbon thin films deposited by DC magnetron sputtering.

PubMed

Khun, N W; Liu, E

2011-06-01

Nitrogen doped diamond-like carbon thin films were deposited on highly conductive p-silicon(100) substrates using a DC magnetron sputtering deposition system by varying working pressure in the deposition chamber. The bonding structure, adhesion strength, surface roughness and corrosion behavior of the films were investigated by using X-ray photoelectron spectroscopy, micro-Raman spectroscopy, micro-scratch test, atomic force microscopy and potentiodynamic polarization test. A 0.6 M NaCl electrolytic solution was used for the corrosion tests. The optimum corrosion resistance of the films was found at a working pressure of 7 mTorr at which a good balance between the kinetics of the sputtered ions and the surface mobility of the adatoms promoted a microstructure of the films with fewer porosities.

High resolution, monochromatic x-ray topography capability at CHESS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finkelstein, K. D., E-mail: kdf1@cornell.edu; Pauling, A.; Brown, Z.

2016-07-27

CHESS has a monochromatic x-ray topography capability serving continually expanding user interest. The setup consists of a beam expanding monochromator, 6-circle diffactometer, and CHESS designed CMOS camera with real time sample-alignment capability. This provides rocking curve mapping with angle resolution as small as 2 µradians, spatial resolution to 3 microns, and field of view up to 7mm. Thus far the capability has been applied for: improving CVD-diamond growth, evaluating perfection of ultra-thin diamond membranes, correlating performance of diamond-based electronics with crystal defect structure, and defect analysis of single crystal silicon carbide. This paper describes our topography system, explains its capabilities,more » and presents experimental results from several applications.« less

Case Conceptualization and Treatment of Comorbid Body Dysmorphic Disorder and Bulimia Nervosa

ERIC Educational Resources Information Center

Didie, Elizabeth R.; Reinecke, Mark A.; Phillips, Katharine A.

2010-01-01

Body dysmorphic disorder (BDD) and eating disorders often co-occur and share some clinical features. In addition, the co-occurrence of BDD and an eating disorder may be associated with greater impairment in functioning. Furthermore, clinical impressions suggest that this comorbidity may be more treatment resistant than either disorder alone. The…

Cognitive-Behavioral Body Image Therapy for Body Dysmorphic Disorder.

ERIC Educational Resources Information Center

Rosen, James C.; And Others

1995-01-01

Randomly assigned 54 body dysmorphic disorder (BDD) subjects to cognitive behavior therapy or no treatment. BDD symptoms were significantly decreased in therapy subjects and the disorder was eliminated in 82 percent of cases at posttreatment and 77 percent at follow-up. Subjects' overall psychological symptoms and self-esteem also improved. (RJM)

Childhood Abuse and Neglect in Body Dysmorphic Disorder

ERIC Educational Resources Information Center

Didie, Elizabeth R.; Tortolani, Christina C.; Pope, Courtney G.; Menard, William; Fay, Christina; Phillips, Katharine A.

2006-01-01

Objective: No published studies have examined childhood abuse and neglect in body dysmorphic disorder (BDD). This study examined the prevalence and clinical correlates of abuse and neglect in individuals with this disorder. Methods: Seventy-five subjects (69.3% female, mean age = 35.4 +/- 12.0) with DSM-IV BDD completed the Childhood Trauma…

Stress exposure and generation: A conjoint longitudinal model of body dysmorphic symptoms, peer acceptance, popularity, and victimization.

PubMed

Webb, Haley J; Zimmer-Gembeck, Melanie J; Mastro, Shawna

2016-09-01

This study examined the bidirectional (conjoint) longitudinal pathways linking adolescents' body dysmorphic disorder (BDD) symptoms with self- and peer-reported social functioning. Participants were 367 Australian students (45.5% boys, mean age=12.01 years) who participated in two waves of a longitudinal study with a 12-month lag between assessments. Participants self-reported their symptoms characteristic of BDD, and perception of peer acceptance. Classmates reported who was popular and victimized in their grade, and rated their liking (acceptance) of their classmates. In support of both stress exposure and stress generation models, T1 victimization was significantly associated with more symptoms characteristic of BDD at T2 relative to T1, and higher symptom level at T1 was associated with lower perceptions of peer acceptance at T2 relative to T1. These results support the hypothesized bidirectional model, whereby adverse social experiences negatively impact symptoms characteristic of BDD over time, and symptoms also exacerbate low perceptions of peer-acceptance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stress engineering of high-quality single crystal diamond by heteroepitaxial lateral overgrowth

DOE PAGES

Tang, Y. -H.; Golding, B.

2016-02-02

Here, we describe a method for lateral overgrowth of low-stress single crystal diamond by chemical vapor deposition (CVD). The process is initiated by deposition of a thin (550 nm) (001) diamond layer on Ir-buffered a-plane sapphire. The diamond is partially masked by periodic thermally evaporated Au stripes using photolithography. Lateral overgrowth of the Au occurs with extremely effective filtering of threading dislocations. Thermal stress resulting from mismatch of the low thermal expansion diamond and the sapphire substrate is largely accommodated by the ductile Au layer. The stress state of the diamond is investigated by Raman spectroscopy for two thicknesses: atmore » 10 μm where the film has just overgrown the Au mask and at 180 μm where the film thickness greatly exceeds the scale of the masking. For the 10-μm film, the Raman linewidth shows spatial oscillations with the period of the Au stripes with a factor of 2 to 3 reduction relative to the unmasked region. In a 180-μm thick diamond film, the overall surface stress was extremely low, 0.00 ± 0.16 GPa, obtained from the Raman shift averaged over the 7.5mm diameter of the crystal at its surface. We conclude that the metal mask protects the overgrown diamond layer from substrate-induced thermal stress and cracking. Lastly, it is also responsible for low internal stress by reducing dislocation density by several orders of magnitude.« less

Nature and origin of interstellar diamond from the Allende CV3 meteorite

NASA Technical Reports Server (NTRS)

Blake, David; Freund, Friedemann; Bunch, Ted; Krishnan, Kannan; Stampfer, Mitch; Chang, Sherwood; Tielens, Alexander G. G. M.

1990-01-01

Data and experimental evidence which support the contention that the C delta diamonds may result from grain-grain collisions in supernova shocks in the interstellar medium are presented. Fragments of the Allende CV3 chondrite were acid-treated. A whitish powder was obtained. For the Analytical Electron Microscopy (AEM) a small drop of ethanol suspension was transferred onto holey carbon support films on 3 mm EM grids. The AEM was performed on transmission-thin fragments of the material which overlay holes in the film, to eliminate interference from the substrate. Electron Spectroscopy for Chemical Analysis (ESCA) was performed on a large aliquot of C. Diamond was identified by selected area electron diffraction. Scanning Transmission Electron Microscope / Energy Dispersive X-ray (STEM-EDS) microanalyses of the C delta diamond, using a light-element detector, show that oxygen and possibly nitrogen are the only impurities consistently present. ESCA spectra from bulk C delta material confirm the presence of N at a level of 0.35 percent or less. Under UV irradiation a yellow-red fluorescence is observed, consistent with that of natural diamonds containing substitutional N. Electron Energy Loss Spectra (EELS) were recorded at 2 eV resolution from the C delta diamond, high pressure synthetic diamond, a diamond film produced in a low pressure plasma by chemical vapor deposition (CVD) on a heated silicon substrate (Roy, 1987), graphite, and amorphous arc sputtered carbon. Comparison of the carbon K edge shape and fine structure shows the Allende C delta phase to be largely diamond, but with a significant pre-edge absorption feature indicative of transitions of C 1s electrons into pi asterisk orbitals which are absent in the purely sp(3)-bonded diamond but present in graphite and amorphous carbon.

Circumventing furin enhances factor VIII biological activity and ameliorates bleeding phenotypes in hemophilia models

PubMed Central

Siner, Joshua I.; Samelson-Jones, Benjamin J.; Crudele, Julie M.; French, Robert A.; Lee, Benjamin J.; Zhou, Shanzhen; Merricks, Elizabeth; Raymer, Robin; Camire, Rodney M.; Arruda, Valder R.

2016-01-01

Processing by the proprotein convertase furin is believed to be critical for the biological activity of multiple proteins involved in hemostasis, including coagulation factor VIII (FVIII). This belief prompted the retention of the furin recognition motif (amino acids 1645–1648) in the design of B-domain–deleted FVIII (FVIII-BDD) products in current clinical use and in the drug development pipeline, as well as in experimental FVIII gene therapy strategies. Here, we report that processing by furin is in fact deleterious to FVIII-BDD secretion and procoagulant activity. Inhibition of furin increases the secretion and decreases the intracellular retention of FVIII-BDD protein in mammalian cells. Our new variant (FVIII-ΔF), in which this recognition motif is removed, efficiently circumvents furin. FVIII-ΔF demonstrates increased recombinant protein yields, enhanced clotting activity, and higher circulating FVIII levels after adeno-associated viral vector–based liver gene therapy in a murine model of severe hemophilia A (HA) compared with FVIII-BDD. Moreover, we observed an amelioration of the bleeding phenotype in severe HA dogs with sustained therapeutic FVIII levels after FVIII-ΔF gene therapy at a lower vector dose than previously employed in this model. The immunogenicity of FVIII-ΔF did not differ from that of FVIII-BDD as a protein or a gene therapeutic. Thus, contrary to previous suppositions, FVIII variants that can avoid furin processing are likely to have enhanced translational potential for HA therapy. PMID:27734034

Inferring other people's states of mind: Comparison across social anxiety, body dysmorphic, and obsessive-compulsive disorders.

PubMed

Buhlmann, Ulrike; Wacker, Renata; Dziobek, Isabel

2015-08-01

Social anxiety disorder (SAD) and body dysmorphic disorder (BDD) are characterized by fears of negative evaluation by others (related to one's own incompetence or flawed appearance, respectively). Previous research has shown that individuals with SAD and BDD exhibit difficulty identifying facial expressions and interpretive biases for threat in social situations. The current study aimed at further investigating social cognition in SAD, BDD, and mentally healthy controls (35 individuals per group, respectively). Further, 35 individuals with obsessive-compulsive disorder (OCD) as a clinical control group not characterized by evaluation fears were included. The Movie for the Assessment of Social Cognition (MASC) was applied. It consists of 45 video sequences depicting interactions among four people at a dinner party. Participants are instructed to evaluate each scenario with respect to the characters' emotions, thoughts, and intentions from a bystander perspective (i.e. other-referent context). Only the socially anxious groups (SAD and BDD) were overall less accurate than the other groups in correctly interpreting the social situations, whereas no difference was obtained between the OCD and the control group. Further analyses indicated that the SAD and BDD groups were less accurate in identifying other people's thoughts and intentions, whereas, again, no difference was observed between the OCD and control groups. In addition, the SAD group was less accurate in inferring thoughts and intentions than the OCD group. Interestingly, the groups did not differ with respect to identifying other people's emotions. These results mostly confirm existing cognitive-behavioral models of SAD and BDD emphasizing that biased interpretation of what others think or intend is one of the key factors maintaining social anxiety and appearance-related concerns. Our study shows that this bias generalizes to social situations in which individuals take a third-person observer perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

Electrical conductivity enhancement by boron-doping in diamond using first principle calculations

NASA Astrophysics Data System (ADS)

Ullah, Mahtab; Ahmed, Ejaz; Hussain, Fayyaz; Rana, Anwar Manzoor; Raza, Rizwan

2015-04-01

Boron doping in diamond plays a vital role in enhancing electrical conductivity of diamond by making it a semiconductor, a conductor or even a superconductor. To elucidate this fact, partial and total density of states has been determined as a function of B-content in diamond. Moreover, the orbital charge distributions, B-C bond lengths and their population have been studied for B-doping in pristine diamond thin films by applying density functional theory (DFT). These parameters have been found to be influenced by the addition of different percentages of boron atoms in diamond. The electronic density of states, B-C bond situations as well as variations in electrical conductivities of diamond films with different boron content and determination of some relationship between these parameters were the basic tasks of this study. Diamond with high boron concentration (∼5.88% B-atoms) showed maximum splitting of energy bands (caused by acceptor impurity states) at the Fermi level which resulted in the enhancement of electron/ion conductivities. Because B atoms either substitute carbon atoms and/or assemble at grain boundaries (interstitial sites) inducing impurity levels close to the top of the valence band. At very high B-concentration, impurity states combine to form an impurity band which accesses the top of the valence band yielding metal like conductivity. Moreover, bond length and charge distributions are found to decrease with increase in boron percentage in diamond. It is noted that charge distribution decreased from +1.89 to -1.90 eV whereas bond length reduced by 0.04 Å with increasing boron content in diamond films. These theoretical results support our earlier experimental findings on B-doped diamond polycrystalline films which depict that the addition of boron atoms to diamond films gives a sudden fall in resistivity even up to 105 Ω cm making it a good semiconductor for its applications in electrical devices.

Cutting thin sections of bone

NASA Technical Reports Server (NTRS)

Ashley, W. W.

1972-01-01

Medical equipment for obtaining repetitive planoparallel sections of bone to study healing of bone structure under high gravity stress is described. Device consists of modified saw with diamond cutting edges. Construction of device and manner of use are explained.

Diamond-like nanocomposite: a novel promising carbon based thin film as antireflection and passivation coating for silicon solar cell

NASA Astrophysics Data System (ADS)

Jana, Sukhendu; Das, Sayan; De, Debasish; Mondal, Anup; Gangopadhyay, Utpal

2018-02-01

Presently, silicon nitride (SiN x ) is widely used as antireflection coating (ARC) on p-type silicon solar cell. But, two highly toxic gasses ammonia and silane are used. In the present study, the ARC and passivation properties of diamond-like nanocomposite (DLN) thin film on silicon solar cell have been investigated. The DLN thin film has been deposited by rf-PACVD process using liquid precursor HMDSO in argon plasma. The film has been characterized by FESEM, HRTEM, FTIR, and Raman spectroscopy. The optical properties have been estimated by UV-vis-NIR spectroscopy. The minimum reflection has been achieved to 0.75% at 630 nm. Both the short circuit current density and open circuit voltage has been increased significantly from 28.6 mA cm-2 to 35.5 mA cm-2 and 0.551 V to 0.613 V respectively. The field effect passivation has been confirmed by dark IV characterization of c-Si /DLN heterojunction structure. All these lead to enhancement of efficiency by almost 4% absolute, which is comparable to SiN x . The ammonia and silane free deposited DLN thin film has a great potential to use as ARC for silicon based solar cell.

Corrosion behavior of aluminum doped diamond-like carbon thin films in NaCl aqueous solution.

PubMed

Khun, N W; Liu, E

2010-07-01

Aluminum doped diamond-like carbon (DLC:Al) thin films were deposited on n-Si(100) substrates by co-sputtering a graphite target under a fixed DC power (650 W) and an aluminum target under varying DC power (10-90 W) at room temperature. The structure, adhesion strength and surface morphology of the DLC:Al films were characterized by X-ray photoelectron spectroscopy (XPS), micro-scratch testing and atomic force microscopy (AFM), respectively. The corrosion performance of the DLC:Al films was investigated by means of potentiodynamic polarization testing in a 0.6 M NaCl aqueous solution. The results showed that the polarization resistance of the DLC:Al films increased from about 18 to 30.7 k(omega) though the corrosion potentials of the films shifted to more negative values with increased Al content in the films.

A petrographic thin sectioning technique for evaluating composite materials

NASA Technical Reports Server (NTRS)

Parker, D. S.; Yee, A. F.

1989-01-01

Petrographic thin sectioning by a low-speed diamond saw has been used in conjunction with transmission polarized light microscopy for the characterization of the microstructure and deformation mechanisms of a variety of polymer systems. It has proven possible by these means to study three types of thermoplastic matrices for composite applications: PEEK, BPA-based polycarbonate (PC), and a rubber-modified PC. The reinforcing fibers for these matrices were in all cases AS4 carbon fibers, unidirectionally arrayed. Superior analyzability of matrix morphology and subsurface fracture processes is achieved by thin sectioning.

Body Dysmorphic Disorder and Other Clinically Significant Body Image Concerns in Adolescent Psychiatric Inpatients: Prevalence and Clinical Characteristics

ERIC Educational Resources Information Center

Dyl, Jennifer; Kittler, Jennifer; Phillips, Katharine A.; Hunt, Jeffrey I.

2006-01-01

Background: This study assessed prevalence and clinical correlates of body dysmorphic disorder (BDD), eating disorders (ED), and other clinically significant body image concerns in 208 consecutively admitted adolescent inpatients. It was hypothesized that adolescents with BDD would have higher levels of depression, anxiety, and suicidality.…

[Body dysmorphic disorder and aesthetic surgery: A systematic review].

PubMed

Kerfant, N; Henry, A-S; Ta, P; Trimaille, A; Philandrianos, C; Hu, W

2015-12-01

Patients suffering from body dysmorphic disorder (BDD) are preoccupied with an imagined or minor defect in appearance that causes significant distress and impairment in social and occupational functioning. Despite a rate of up to 15% of BDD patients reported in cosmetic surgery settings, there is no consensus on the best management for these patients. The main purpose of this article was to conduct a literature review on BDD and cosmetic surgery. Properly trained healthcare professionals in recognizing and diagnosing this pathology is essential for the delivery of quality psychiatric care while taking into account the high prevalence of body dysmorphic disorder patients in cosmetic surgery and the poor outcome of these patients following cosmetic procedures. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics.

PubMed

Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz; Shvyd'ko, Yuri

2016-12-01

We report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-μm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ≃8 keV X-rays. All of the components of the bending mechanism (about 10 parts) are manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.

Single crystal CVD diamond membranes for betavoltaic cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Delfaure, C.; Pomorski, M., E-mail: michal.pomorski@cea.fr; Sanoit, J. de

2016-06-20

A single crystal diamond large area thin membrane was assembled as a p-doped/Intrinsic/Metal (PIM) structure and used in a betavoltaic configuration. When tested with a 20 keV electron beam from a high resolution scanning electron microscope, we measured an open circuit voltage (V{sub oc}) of 1.85 V, a charge collection efficiency (CCE) of 98%, a fill-factor of 80%, and a total conversion efficiency of 9.4%. These parameters are inherently linked to the diamond membrane PIM structure that allows full device depletion even at 0 V and are among the highest reported up to now for any other material tested for betavoltaic devices. Itmore » enables to drive a high short-circuit current I{sub sc} up to 7.12 μA, to reach a maximum power P{sub max} of 10.48 μW, a remarkable value demonstrating the high-benefit of diamond for the realization of long-life radioisotope based micro-batteries.« less

Growth of diamond by RF plasma-assisted chemical vapor deposition

NASA Technical Reports Server (NTRS)

Meyer, Duane E.; Ianno, Natale J.; Woollam, John A.; Swartzlander, A. B.; Nelson, A. J.

1988-01-01

A system has been designed and constructed to produce diamond particles by inductively coupled radio-frequency, plasma-assisted chemical vapor deposition. This is a low-pressure, low-temperature process used in an attempt to deposit diamond on substrates of glass, quartz, silicon, nickel, and boron nitride. Several deposition parameters have been varied including substrate temperature, gas concentration, gas pressure, total gas flow rate, RF input power, and deposition time. Analytical methods employed to determine composition and structure of the deposits include scanning electron microscopy, absorption spectroscopy, scanning Auger microprobe spectroscopy, and Raman spectroscopy. Analysis indicates that particles having a thin graphite surface, as well as diamond particles with no surface coatings, have been deposited. Deposits on quartz have exhibited optical bandgaps as high as 4.5 eV. Scanning electron microscopy analysis shows that particles are deposited on a pedestal which Auger spectroscopy indicates to be graphite. This is a phenomenon that has not been previously reported in the literature.

Preparation of fluorescent nanodiamond suspensions using bead-assisted ultrasonic disintegration

NASA Astrophysics Data System (ADS)

Głowacki, Maciej J.; Gardas, Mateusz; Ficek, Mateusz; Sawczak, Mirosław; Bogdanowicz, Robert

2017-08-01

Nitrogen-vacancy (N-V) centers are the most widely studied crystallographic defect in the diamond lattice since their presence causes strong and stable fluorescence. The negative charge state of the defect (NV-) is especially desired because of its potential for quantum information processing. In this study, fluorescent suspensions of diamond particles have been produced by microbead-assisted ultrasonic disintegration of commercially obtained diamond powder containing N-V color centers. Zirconium dioxide ZrO2 was chosen as an abrasive and a mixture of deionized water and dimethyl sulfoxide (DMSO) was used as a solvent. Raman spectrum of the starting material has been obtained and the resulting liquids have been measured in terms of photoluminescence. Moreover, thin layer of the diamond particles has been deposited on a silicon substrate and examined using scanning electron microscopy (SEM). During the course of the experiment a new method, which uses sodium chloride NaCl as an abrasive, has been proposed. The results of fluorescence measurements of the suspension prepared using this technique are highly promising.

Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics

DOE PAGES

Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz; ...

2016-12-29

Here, we report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-µm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ' 8 keV X-rays. All of the components of the bending mechanism (about 10 parts) aremore » manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons, and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.« less

Curved diamond-crystal spectrographs for x-ray free-electron laser noninvasive diagnostics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terentyev, Sergey; Blank, Vladimir; Kolodziej, Tomasz

Here, we report on the manufacturing and X-ray tests of bent diamond-crystal X-ray spectrographs, designed for noninvasive diagnostics of the X-ray free-electron laser (XFEL) spectra in the spectral range from 5 to 15 keV. The key component is a curved, 20-µm thin, single crystalline diamond triangular plate in the (110) orientation. The radius of curvature can be varied between R = 0.6 m and R = 0.1 m in a controlled fashion, ensuring imaging in a spectral window of up to 60 eV for ' 8 keV X-rays. All of the components of the bending mechanism (about 10 parts) aremore » manufactured from diamond, thus ensuring safe operations in intense XFEL beams. The spectrograph is transparent to 88% for 5-keV photons, and to 98% for 15-keV photons. Therefore, it can be used for noninvasive diagnostics of the X-ray spectra during XFEL operations.« less

Correlation of Radiation Dosage With Mechanical Properties of Thin Films

NASA Technical Reports Server (NTRS)

Newton, R. L.

2003-01-01

The objective of this investigation was to examine the relationship between irradiation level (proton dose), microstructure, and stress levels in chemical vapor deposited diamond and polysilicon film using crosssectioned specimens. However, the emphasis was placed on the diamond specimen because diamond holds much promise for use in advanced technologies. The use of protons allows not only the study of the charged particle that may cause the most microstructural damage in Earth-orbit microelectromechanical systems (MEMS) devices, but also allows the study of relatively deeply buried damage inside the diamond material. Using protons allows these studies without having to resort to megaelectronvolt implant energies that may create extensive damage due to the high energy that is needed for the implantation process. Since 1 MEMS devices operating in space will not have an opportunity to reverse radiation damage via annealing, only nonannealed specimens were investigated. The following three high spatial resolution techniques were used to examine these relationships: (I) Scanning electron microscopy, (2) micro-Raman spectroscopy, and (3) micro x-ray diffraction.

High performance diamond-like carbon layers obtained by pulsed laser deposition for conductive electrode applications

NASA Astrophysics Data System (ADS)

Stock, F.; Antoni, F.; Le Normand, F.; Muller, D.; Abdesselam, M.; Boubiche, N.; Komissarov, I.

2017-09-01

For the future, one of the biggest challenge faced to the technologies of flat panel display and various optoelectronic and photovoltaic devices is to find an alternative to the use of transparent conducting oxides like ITO. In this new approach, the objective is to grow high conductive thin-layer graphene (TLG) on the top of diamond-like carbon (DLC) layers presenting high performance. DLC prepared by pulsed laser deposition (PLD) have attracted special interest due to a unique combination of their properties, close to those of monocrystalline diamond, like its transparency, hardness and chemical inertia, very low roughness, hydrogen-free and thus high thermal stability up to 1000 K. In our future work, we plane to explore the synthesis of conductive TLG on top of insulating DLC thin films. The feasibility and obtained performances of the multi-layered structure will be explored in great details in the short future to develop an alternative to ITO with comparable performance (conductivity of transparency). To select the best DLC candidate for this purpose, we focus this work on the physicochemical properties of the DLC thin films deposited by PLD from a pure graphite target at two wavelengths (193 and 248 nm) at various laser fluences. A surface graphenization process, as well as the required efficiency of the complete structure (TLG/DLC) will clearly be related to the DLC properties, especially to the initial sp3/sp2 hybridization ratio. Thus, an exhaustive description of the physicochemical properties of the DLC layers is a fundamental step in the research of comparable performance to ITO.

Successful fabrication of a convex platform PMMA cell-counting slide using a high-precision perpendicular dual-spindle CNC machine tool

NASA Astrophysics Data System (ADS)

Chen, Shun-Tong; Chang, Chih-Hsien

2013-12-01

This study presents a novel approach to the fabrication of a biomedical-mold for producing convex platform PMMA (poly-methyl-meth-acrylate) slides for counting cells. These slides allow for the microscopic examination of urine sediment cells. Manufacturing of such slides incorporates three important procedures: (1) the development of a tabletop high-precision dual-spindle CNC (computerized numerical control) machine tool; (2) the formation of a boron-doped polycrystalline composite diamond (BD-PCD) wheel-tool on the machine tool developed in procedure (1); and (3) the cutting of a multi-groove-biomedical-mold array using the formed diamond wheel-tool in situ on the developed machine. The machine incorporates a hybrid working platform providing wheel-tool thinning using spark erosion to cut, polish, and deburr microgrooves on NAK80 steel directly. With consideration given for the electrical conductive properties of BD-PCD, the diamond wheel-tool is thinned to a thickness of 5 µm by rotary wire electrical discharge machining. The thinned wheel-tool can grind microgrooves 10 µm wide. An embedded design, which inserts a close fitting precision core into the biomedical-mold to create step-difference (concave inward) of 50 µm in height between the core and the mold, is also proposed and realized. The perpendicular dual-spindles and precision rotary stage are features that allow for biomedical-mold machining without the necessity of uploading and repositioning materials until all tasks are completed. A PMMA biomedical-slide with a plurality of juxtaposed counting chambers is formed and its usefulness verified.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gamboa, E. J.; Fletcher, L. B.; Lee, H. J.

The extraordinary mechanical and optical properties of diamond are the basis of numerous technical applications and make diamond anvil cells a premier device to explore the high-pressure behavior of materials. However, at applied pressures above a few hundred GPa, optical probing through the anvils becomes difficult because of the pressure-induced changes of the transmission and the excitation of a strong optical emission. Such features have been interpreted as the onset of a closure of the optical gap in diamond, and can significantly impair spectroscopy of the material inside the cell. In contrast, a comparable widening has been predicted for purelymore » hydrostatic compressions, forming a basis for the presumed pressure stiffening of diamond and resilience to the eventual phase change to BC8. We here present the first experimental evidence of this effect at geo-planetary pressures, exceeding the highest ever reported hydrostatic compression of diamond by more than 200 GPa and any other measurement of the band gap by more than 350 GPa. We here apply laser driven-ablation to create a dynamic, high pressure state in a thin, synthetic diamond foil together with frequency-resolved x-ray scattering as a probe. The frequency shift of the inelastically scattered x-rays encodes the optical properties and, thus, the behavior of the band gap in the sample. Using the ultra-bright x-ray beam from the Linac Coherent Light Source (LCLS), we observe an increasing direct band gap in diamond up to a pressure of 370 GPa. This finding points to the enormous strains in the anvils and the impurities in natural Type Ia diamonds as the source of the observed closure of the optical window. Our results demonstrate that diamond remains an insulating solid to pressures approaching its limit strength.« less

A mechanistic-empirical approach for evaluating the effect of diamond grinding and thin overlay on predicted pavement performance.

DOT National Transportation Integrated Search

2016-04-01

Advancements in pavement management practice require evaluating the performance of pavement preservation treatments using performance-related characteristics. However, state highway agencies face the challenge of developing performance-based relation...

Power Mems Development

DTIC Science & Technology

2010-11-30

testing and analysis in ONR laboratories. Task 1.2 Contributors: Sunny Kedia, Shinzo Onishi , Scott Samson, Drew Hanser Task 1.2 Deliverable...Priscila Spagnol, Shinzo Onishi , Drew Hanser, Weidong Wang, Sunny Kedia, John Bumgarner Deliverable: Prototype device fabricated on a thin-film diamond

Power Mems Development

DTIC Science & Technology

2010-12-31

laboratories. Task 1.2 Contributors: Sunny Kedia, Shinzo Onishi , Scott Samson, Drew Hanser Task 1.2 Deliverable: Functional MEMS-based DC-DC...Shinzo Onishi , Drew Hanser, Weidong Wang, Sunny Kedia, John Bumgarner Deliverable: Prototype device fabricated on a thin-film diamond heat spreader

Friction and Wear Properties of As-Deposited and Carbon Ion-Implanted Diamond Films

NASA Technical Reports Server (NTRS)

Miyoshi, Kazuhisa

1996-01-01

Recent work on the friction and wear properties of as-deposited and carbon ion-implanted diamond films was reviewed. Diamond films were produced by the microwave plasma chemical vapor deposition (CVD) technique. Diamond films with various grain sizes and surface roughnesses were implanted with carbon ions at 60 keV ion energy, resulting in a dose of 1.2 x 10(exp 17) carbon ions per cm(exp 2). Various analytical techniques, including Raman spectroscopy, proton recoil analysis, Rutherford backscattering, transmission and scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction, were utilized to characterize the diamond films. Sliding friction experiments were conducted with a polished natural diamond pin in contact with diamond films in the three environments: humid air (40% relative humidity), dry nitrogen (less than 1 percent relative humidity), and ultrahigh vacuum (10(exp -7) Pa). The CVD diamond films indeed have friction and wear properties similar to those of natural diamond in the three environments. The as-deposited, fine-grain diamond films can be effectively used as self-lubricating, wear-resistant coatings that have low coefficients of friction (0.02 to 0.04) and low wear rates (10(exp -7) to lO(exp -8) mm(exp 3) N(exp -1) m(exp -1)) in both humid air and dry nitrogen. However, they have high coefficients of friction (1.5 to 1.7) and a high wear rate (10(exp -4) mm(exp 7) N(exp -1) m(exp -1)) in ultrahigh vacuum. The carbon ion implantation produced a thin surficial layer (less than 0.1 micron thick) of amorphous, non-diamond carbon on the diamond films. In humid air and dry nitrogen, the ion-implanted, fine and coarse-grain diamond films have a low coefficient of friction (around 0.1) and a low wear rate (10(exp -7) mm(exp 3) N(exp -1) m(exp-1)). Even in ultrahigh vacuum, the presence of the non-diamond carbon layer reduced the coefficient of friction of fine-grain diamond films to 0.1 or lower and the wear rate to 10(exp -6) mm(exp 3) N(exp -1) m(exp -1). Thus, the carbon ion-implanted, fine-grain diamond films can be effectively used as wear-resistant, self-lubricating coatings not only in air and dry nitrogen, but also in ultrahigh vacuum.

Kinetics of the electrochemical mineralization of perfluorooctanoic acid on ultrananocrystalline boron doped conductive diamond electrodes.

PubMed

Urtiaga, Ane; Fernández-González, Carolina; Gómez-Lavín, Sonia; Ortiz, Inmaculada

2015-06-01

This work deals with the electrochemical degradation and mineralization of perfluorooctanoic acid (PFOA). Model aqueous solutions of PFOA (100mg/L) were electro-oxidized under galvanostatic conditions in a flow-by undivided cell provided with a tungsten cathode and an anode formed by a commercial ultrananocrystalline boron doped diamond (BDD) coating on a niobium substrate. A systematic experimental study was conducted in order to analyze the influence of the following operation variables: (i) the supporting electrolyte, NaClO4 (1.4 and 8.4g/L) and Na2SO4 (5g/L); (ii) the applied current density, japp, in the range 50-200 A/m(2) and (iii) the hydrodynamic conditions, in terms of flowrate in the range 0.4×10(-4)-1.7×10(-4)m(3)/s and temperature in the range 293-313K. After 6h of treatment and at japp 200A/m(2), PFOA removal was higher than 93% and the mineralization ratio, obtained from the decrease of the total organic carbon (TOC) was 95%. The electrochemical generation of hydroxyl radicals in the supporting electrolyte was experimentally measured based on their reaction with dimethyl sulfoxide. The enhanced formation of hydroxyl radicals at higher japp was related to the faster kinetics of PFOA removal. The fitting of experimental data to the proposed kinetic model provided the first order rate constants of PFOA degradation, kc(1) that moved from 2.06×10(-4) to 15.58×10(-4)s(-1), when japp varied from 50 to 200A/m(2). Copyright © 2014 Elsevier Ltd. All rights reserved.

Boron-doped diamond electrooxidation of ethyl paraben: The effect of electrolyte on by-products distribution and mechanisms.

PubMed

Frontistis, Zacharias; Antonopoulou, Maria; Yazirdagi, Melis; Kilinc, Zeynep; Konstantinou, Ioannis; Katsaounis, Alexandros; Mantzavinos, Dionissios

2017-06-15

Ethyl paraben (EP), a representative emerging pollutant of the parabens family, was subject to electrochemical oxidation over a boron-doped diamond (BDD) anode. Experiments were carried out in a single-compartment cell at 10-70 mA cm -2 current density, 200-600 μg L -1 EP concentration, initial solution pH 3-9 and 0.1 M electrolyte concentration. The degradation rate is favored at increased current densities and in the presence of NaCl as the supporting electrolyte, while the pH effect is inconsiderable. For instance, the first order rate constant for the degradation of 200 μg L -1 EP at 30 mA cm -2 was 0.25, 0.1 and 0.07 min -1 with NaCl, Na 2 SO 4 and HClO 4 , respectively. Degradation in secondary treated wastewater was faster than in pure water presumably due to the action of chloride ions present in the effluent. Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) was employed to determine major transformation by-products (TBPs). The route of EP degradation with Na 2 SO 4 involves hydroxylation and demethylation reactions, signifying the role of electrogenerated hydroxyl radicals in the process. Twenty one TBPs were identified with NaCl as the electrolyte, including several chlorinated and non-chlorinated dimers and trimers; these findings suggest that indirect oxidation mediated by chlorine radicals and other chlorine active species also takes place. In this view, the role of the supporting electrolyte is crucial since it can influence both reaction kinetics and pathways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Boron-doped diamond oxidation of amoxicillin pharmaceutical formulation: Statistical evaluation of operating parameters, reaction pathways and antibacterial activity.

PubMed

Frontistis, Zacharias; Antonopoulou, Maria; Venieri, Danae; Konstantinou, Ioannis; Mantzavinos, Dionissios

2017-06-15

The electrochemical oxidation of a commercial amoxicillin formulation over a boron-doped diamond (BDD) anode was investigated. The effect of initial COD concentration (1-2 g/L), current density (30-50 mA/cm 2 ), treatment time (15-90 min), initial pH (3-9) and electrolyte concentration (2-4 g/L NaCl) on COD removal was assessed through a factorial design methodology. For the range of conditions in question, the first three single effects, as well as the interaction between COD and time were the most important ones in terms of mass of COD removed. Liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) was employed to identify major transformation by-products (TBPs); thirteen compounds were detected as TBPs of AMX electrochemical degradation, while several others appear in the original formulation. AMX degradation occurs though the following pathways: (i) hydroxylation mainly in the benzoic ring, (ii) opening of β-lactam ring followed by decarboxylation, hydroxylation and re-arrangement, and (iii) bond cleavage between the carbons of amino and amide groups. Furthermore, the process is accompanied by the release of several ions, i.e. nitrate, sulfate and ammonium. The antibiotic activity of AMX up to 1000 mg/L was tested against Klebsiella pneumoniae and Enterococcus faecalis reference strains; both bacteria are completely inactivated at this concentration but the activity is reduced substantially at lower concentrations. Oxidized samples still exhibit some antibacterial activity (50-60%) which is due to TBPs and active chlorine species present in the liquid phase. The latter are generated from chloride ions and enhance considerably AMX degradation rates. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anorexia nervosa and body dysmorphic disorder are associated with abnormalities in processing visual information.

PubMed

Li, W; Lai, T M; Bohon, C; Loo, S K; McCurdy, D; Strober, M; Bookheimer, S; Feusner, J

2015-07-01

Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are characterized by distorted body image and are frequently co-morbid with each other, although their relationship remains little studied. While there is evidence of abnormalities in visual and visuospatial processing in both disorders, no study has directly compared the two. We used two complementary modalities--event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI)--to test for abnormal activity associated with early visual signaling. We acquired fMRI and ERP data in separate sessions from 15 unmedicated individuals in each of three groups (weight-restored AN, BDD, and healthy controls) while they viewed images of faces and houses of different spatial frequencies. We used joint independent component analyses to compare activity in visual systems. AN and BDD groups demonstrated similar hypoactivity in early secondary visual processing regions and the dorsal visual stream when viewing low spatial frequency faces, linked to the N170 component, as well as in early secondary visual processing regions when viewing low spatial frequency houses, linked to the P100 component. Additionally, the BDD group exhibited hyperactivity in fusiform cortex when viewing high spatial frequency houses, linked to the N170 component. Greater activity in this component was associated with lower attractiveness ratings of faces. Results provide preliminary evidence of similar abnormal spatiotemporal activation in AN and BDD for configural/holistic information for appearance- and non-appearance-related stimuli. This suggests a common phenotype of abnormal early visual system functioning, which may contribute to perceptual distortions.

Long-Term Outcomes of Cognitive-Behavioral Therapy for Adolescent Body Dysmorphic Disorder.

PubMed

Krebs, Georgina; de la Cruz, Lorena Fernández; Monzani, Benedetta; Bowyer, Laura; Anson, Martin; Cadman, Jacinda; Heyman, Isobel; Turner, Cynthia; Veale, David; Mataix-Cols, David

2017-07-01

Emerging evidence suggests that cognitive-behavioral therapy (CBT) is an efficacious treatment for adolescent body dysmorphic disorder (BDD) in the short term, but longer-term outcomes remain unknown. The current study aimed to follow up a group of adolescents who had originally participated in a randomized controlled trial of CBT for BDD to determine whether treatment gains were maintained. Twenty-six adolescents (mean age = 16.2, SD = 1.6) with a primary diagnosis of BDD received a course of developmentally tailored CBT and were followed up over 12 months. Participants were assessed at baseline, midtreatment, posttreatment, 2-, 6-, and 12-month follow-up. The primary outcome measure was the clinician-rated Yale-Brown Obsessive-Compulsive Scale Modified for BDD. Secondary outcomes included measures of insight, depression, quality of life, and global functioning. BDD symptoms decreased significantly from pre- to posttreatment and remained stable over the 12-month follow-up. At this time point, 50% of participants were classified as responders and 23% as remitters. Participants remained significantly improved on all secondary outcomes at 12-month follow-up. Neither baseline insight nor baseline depression predicted long-term outcomes. The positive effects of CBT appear to be durable up to 12-month follow-up. However, the majority of patients remained symptomatic and vulnerable to a range of risks at 12-month follow-up, indicating that longer-term monitoring is advisable in this population. Future research should focus on enhancing the efficacy of CBT in order to improve long-term outcomes. Copyright © 2017. Published by Elsevier Ltd.

Neural correlates of treatment response in depressed bipolar adolescents during emotion processing.

PubMed

Diler, Rasim Somer; Ladouceur, Cecile D; Segreti, Annamaria; Almeida, Jorge R C; Birmaher, Boris; Axelson, David A; Phillips, Mary L; Pan, Lisa A

2013-06-01

Depressive mood in adolescents with bipolar disorder (BDd) is associated with significant morbidity and mortality, but we have limited information about neural correlates of depression and treatment response in BDd. Ten adolescents with BDd (8 females, mean age = 15.6 ± 0.9) completed two (fearful and happy) face gender labeling fMRI experiments at baseline and after 6-weeks of open treatment. Whole-brain analysis was used at baseline to compare their neural activity with those of 10 age and sex-matched healthy controls (HC). For comparisons of the neural activity at baseline and after treatment of youth with BDd, region of interest analysis for dorsal/ventral prefrontal, anterior cingulate, and amygdala activity, and significant regions identified by wholebrain analysis between BDd and HC were analyzed. There was significant improvement in depression scores (mean percentage change on the Child Depression Rating Scale-Revised 57 % ± 28). Neural activity after treatment was decreased in left occipital cortex in the intense fearful experiment, but increased in left insula, left cerebellum, and right ventrolateral prefrontal cortex in the intense happy experiment. Greater improvement in depression was associated with baseline higher activity in ventral ACC to mild happy faces. Study sample size was relatively small for subgroup analysis and consisted of mainly female adolescents that were predominantly on psychotropic medications during scanning. Our results of reduced negative emotion processing versus increased positive emotion processing after treatment of depression (improvement of cognitive bias to negative and away from positive) are consistent with the improvement of depression according to Beck's cognitive theory.

Dysfunctional Metacognitive Beliefs in Body Dysmorphic Disorder

PubMed Central

Zeinodini, Zahra; Sedighi, Sahar; Rahimi, Mandana Baghertork; Noorbakhsh, Simasadat; Esfahani, Sepideh Rajezi

2016-01-01

The present study aims to examine the correlation of body dysmorphic disorder, with metacognitive subscales, metaworry and thought-fusion. The study was conducted in a correlation framework. Sample included 155 high school students in Isfahan, Iran in 2013-2014, gathered through convenience sampling. To gather data about BDD, Yale-Brown Obsessive Compulsive Scale Modified for BDD was applied. Then, Meta Cognitive Questionnaire, Metaworry Questionnaire, and Thought-Fusion Inventory were used to assess metacognitive subscales, metaworry and thought-fusion. Data obtained from this study were analyzed using Pearson correlation and multiple regressions in SPSS 18. Result indicated YBOCS-BDD scores had a significant correlation with scores from MCQ (P<0.05), MWG (P<0.05), and TFI (P<0.05). Also, multiple regressions were run to predict YBOCS from TFI, MWQ, and MCQ-30. These variables significantly predicted YBOCS [F (3,151) =32.393, R2=0.57]. Findings indicated that body dysmorphic disorder was significantly related to metacognitive subscales, metaworry, and thought fusion in high school students in Isfahan, which is in line with previous studies. A deeper understanding of these processes can broaden theory and treatment of BDD, thereby improve the lives of sufferers and potentially protect others from developing this devastating disorder. PMID:26493420

Is Body Dysmorphic Disorder Associated with Abnormal Bodily Self-Awareness? A Study Using the Rubber Hand Illusion

PubMed Central

Kaplan, Ryan A.; Enticott, Peter G.; Hohwy, Jakob; Castle, David J.; Rossell, Susan L.

2014-01-01

Evidence from past research suggests that behaviours and characteristics related to body dissatisfaction may be associated with greater instability of perceptual body image, possibly due to problems in the integration of body-related multisensory information. We investigated whether people with body dysmorphic disorder (BDD), a condition characterised by body image disturbances, demonstrated enhanced susceptibility to the rubber hand illusion (RHI), which arises as a result of multisensory integration processes when a rubber hand and the participant's hidden real hand are stimulated in synchrony. Overall, differences in RHI experience between the BDD group and healthy and schizophrenia control groups (n = 17 in each) were not significant. RHI strength, however, was positively associated with body dissatisfaction and related tendencies. For the healthy control group, proprioceptive drift towards the rubber hand was observed following synchronous but not asynchronous stimulation, a typical pattern when inducing the RHI. Similar drifts in proprioceptive awareness occurred for the BDD group irrespective of whether stimulation was synchronous or not. These results are discussed in terms of possible abnormalities in visual processing and multisensory integration among people with BDD. PMID:24925079

Evaluation of the SD BIOLINE Dengue Duo rapid test in the course of acute and convalescent dengue infections in a Mexican endemic region.

PubMed

Sánchez-Vargas, Luis A; Sánchez-Marce, Elvis E; Vivanco-Cid, Héctor

2014-04-01

In this study, we evaluated the performance of a rapid test, the SD BIOLINE Dengue Duo (SD BDD) kit, with a panel of serum samples from 310 Mexican patients with diagnosis of dengue infection previously confirmed by reference enzyme-linked immunosorbent assay tests. Eighty-seven negative samples from other febrile illnesses were included as controls. The SD BDD showed an overall sensitivity of 90.65% and specificity of 89.66%. No statistically significant differences were found in the sensitivity of the SD BDD kit compared between primary or secondary infections (87.05% versus 93.57%, respectively, P = 0.0761) and dengue fever or dengue hemorrhagic fever cases (90.77% versus 89.74%, respectively, P = 0.7716). However, a higher sensitivity in the acute phase of dengue infection was found compared with the convalescent phase (93.03% versus 81.82%, respectively, P = 0.0089). These results indicate that the SD BDD kit is a useful tool to diagnose dengue infections, both in primary or secondary infections and mainly during the acute phase. Copyright © 2014 Elsevier Inc. All rights reserved.

Magneto-optical imaging of thin magnetic films using spins in diamond

NASA Astrophysics Data System (ADS)

Simpson, David A.; Tetienne, Jean-Philippe; McCoey, Julia M.; Ganesan, Kumaravelu; Hall, Liam T.; Petrou, Steven; Scholten, Robert E.; Hollenberg, Lloyd C. L.

2016-03-01

Imaging the fields of magnetic materials provides crucial insight into the physical and chemical processes surrounding magnetism, and has been a key ingredient in the spectacular development of magnetic data storage. Existing approaches using the magneto-optic Kerr effect, x-ray and electron microscopy have limitations that constrain further development, and there is increasing demand for imaging and characterisation of magnetic phenomena in real time with high spatial resolution. Here we show how the magneto-optical response of an array of negatively-charged nitrogen-vacancy spins in diamond can be used to image and map the sub-micron stray magnetic field patterns from thin ferromagnetic films. Using optically detected magnetic resonance, we demonstrate wide-field magnetic imaging over 100 × 100 μm2 with sub-micron spatial resolution at video frame rates, under ambient conditions. We demonstrate an all-optical spin relaxation contrast imaging approach which can image magnetic structures in the absence of an applied microwave field. Straightforward extensions promise imaging with sub-μT sensitivity and sub-optical spatial and millisecond temporal resolution. This work establishes practical diamond-based wide-field microscopy for rapid high-sensitivity characterisation and imaging of magnetic samples, with the capability for investigating magnetic phenomena such as domain wall and skyrmion dynamics and the spin Hall effect in metals.

Ultrathin Nanocrystalline Diamond Films with Silicon Vacancy Color Centers via Seeding by 2 nm Detonation Nanodiamonds.

PubMed

Stehlik, Stepan; Varga, Marian; Stenclova, Pavla; Ondic, Lukas; Ledinsky, Martin; Pangrac, Jiri; Vanek, Ondrej; Lipov, Jan; Kromka, Alexander; Rezek, Bohuslav

2017-11-08

Color centers in diamonds have shown excellent potential for applications in quantum information processing, photonics, and biology. Here we report chemical vapor deposition (CVD) growth of nanocrystalline diamond (NCD) films as thin as 5-6 nm with photoluminescence (PL) from silicon-vacancy (SiV) centers at 739 nm. Instead of conventional 4-6 nm detonation nanodiamonds (DNDs), we prepared and employed hydrogenated 2 nm DNDs (zeta potential = +36 mV) to form extremely dense (∼1.3 × 10 13 cm -2 ), thin (2 ± 1 nm), and smooth (RMS roughness < 0.8 nm) nucleation layers on an Si/SiO x substrate, which enabled the CVD growth of such ultrathin NCD films in two different and complementary microwave (MW) CVD systems: (i) focused MW plasma with an ellipsoidal cavity resonator and (ii) pulsed MW plasma with a linear antenna arrangement. Analytical ultracentrifuge, infrared and Raman spectroscopies, atomic force microscopy, and scanning electron microscopy are used for detailed characterization of the 2 nm H-DNDs and the nucleation layer as well as the ultrathin NCD films. We also demonstrate on/off switching of the SiV center PL in the NCD films thinner than 10 nm, which is achieved by changing their surface chemistry.

Total inorganic arsenic detection in real water samples using anodic stripping voltammetry and a gold-coated diamond thin-film electrode.

PubMed

Song, Yang; Swain, Greg M

2007-06-12

An accurate method for total inorganic arsenic determination in real water samples was developed using differential pulse anodic stripping voltammetry (DPASV) and a Au-coated boron-doped diamond thin-film electrode. Keys to the method are the use of a conducting diamond platform and solid phase extraction for sample preparation. In the method, the As(III) present in the sample is first detected by DPASV. The As(V) present is then reduced to As(III) by reaction with Na2SO3 and this is followed by a second detection of As(III) by DPASV. Interfering metal ions (e.g., Cu(II)) that cause decreased electrode response sensitivity for arsenic in real samples are removed by solid phase extraction as part of the sample preparation. For example, Cu(II) caused a 30% decrease in the As stripping peak current at a solution concentration ratio of 3:1 (Cu(II)/As(III)). This loss was mitigated by passage of the solution through a Chelex 100 cation exchange resin. After passage, only a 5% As stripping current response loss was seen. The effect of organic matter on the Au-coated diamond electrode response for As(III) was also evaluated. Humic acid at a 5 ppm concentration caused only a 9% decrease in the As stripping peak charge for Au-coated diamond. By comparison, a 50% response decrease was observed for Au foil. Clearly, the chemical properties of the diamond surface in the vicinity of the metal deposits inhibit molecular adsorption on at least some of the Au surface. The method provided reproducible and accurate results for total inorganic arsenic in two contaminated water samples provided by the U.S. Bureau of Reclamation. The total inorganic As concentration in the two samples, quantified by the standard addition method, was 23.2+/-2.9 ppb for UV plant influent water and 16.4+/-0.9 ppb for Well 119 water (n=4). These values differed from the specified concentrations by less than 4%.

Ellipsometric investigation of nitrogen doped diamond thin films grown in microwave CH{sub 4}/H{sub 2}/N{sub 2} plasma enhanced chemical vapor deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ficek, Mateusz, E-mail: rbogdan@eti.pg.gda.pl; Institute for Materials Research; Sankaran, Kamatchi J.

2016-06-13

The influence of N{sub 2} concentration (1%–8%) in CH{sub 4}/H{sub 2}/N{sub 2} plasma on structure and optical properties of nitrogen doped diamond (NDD) films was investigated. Thickness, roughness, and optical properties of the NDD films in the VIS–NIR range were investigated on the silicon substrates using spectroscopic ellipsometry. The samples exhibited relatively high refractive index (2.6 ± 0.25 at 550 nm) and extinction coefficient (0.05 ± 0.02 at 550 nm) with a transmittance of 60%. The optical investigation was supported by the molecular and atomic data delivered by Raman studies, bright field transmission electron microscopy imaging, and X-ray photoelectron spectroscopy diagnostics. Those results revealed that whilemore » the films grown in CH{sub 4}/H{sub 2} plasma contained micron-sized diamond grains, the films grown using CH{sub 4}/H{sub 2}/(4%)N{sub 2} plasma exhibited ultranano-sized diamond grains along with n-diamond and i-carbon clusters, which were surrounded by amorphous carbon grain boundaries.« less

"Fullerene-like" Raman bands in UHP metamorphic diamonds: Metastable intermediate phases for diamond formation

NASA Astrophysics Data System (ADS)

Harada, Y.; Igarashi, M.; Hashiguchi, Y.; Ogasawara, Y.

2011-12-01

Mysterious Raman bands at 1430-1480 cm-1 suggesting carbon (or carbon-bearing) species have been discovered in UHP metamorphic microdiamonds entirely enclosed in dolomite marble from Kokchetav Massif (Igarashi et al., 2011). Such Raman bands first discovered at some domains in a T-type (see Ishida et al., 2003) diamond in dolomite marble in 2005, but we have not reported this because of the possibility of misidentification by contamination. Later, similar bands were also found in the rim and the core of S-type and R-type. The relative intensities of these Raman bands to diamond (at 1332 cm-1) were 10-40 % in average (max. 90-110 %) and FWHMs are broad (25-45 cm-1). The possibility of the appearance of these Raman bands was low. As we used ordinary polished thin sections (thickness: 25 μm) and the organic materials used in thin section making have Raman bands at ca. 1450 cm-1, we carefully examined observed Raman spectra and the positions of the source materials of these bands to exclude the possibility of contaminations. Examined microdiamond grains are entirely enclosed in the host garnet, and no crack was observed in the host. We conducted 2D Raman mappings at different depths with 2 μm intervals. The result showed that the domains having these Raman bands were located within diamond grains and limited area (1-3 μm). These bands were never detected from outside diamond grains (e.g., host garnet). Thus, the unknown Raman bands at 1430-1480 cm-1 were attributed to some materials inside microdiamonds entirely included in the host garnet. The possibility of contamination was denied. Recently, we found similar Raman bands in the microdiamonds in garnet in Grt-Bt gneiss. Examined microdiamonds are entirely enclosed in garnet grain and no extra phase observed near laser spots in these microdiamond grains under an optical microscope. The Raman bands at 1430-1480 cm-1 were found from 4 microdiamond grains. The peak positions and FWHMs of these bands were as follows: (a) 1433, 31 (b) 1456, 35 (b) 1458, 41 (c) 1461, 31 (e) 1462 cm-1, 44 cm-1. Their intensities to the host diamond were 10-20 % in average. The mappings at different depths also showed very limited source space inside microdiamond grains. Although it is difficult to identify the source materials only by Raman spectroscopy, we considered that the Raman bands could be attributed to some carbon or carbon-bearing species which were relicts as metastable intermediate phases for microdiamond formation under UHP. Fullerenes are speculated as possible carbon materials for those bands. The band at 1470 cm-1 is similar to Ag (2) band of C60 fullerene. The large FWHM and the variation of peak positions at 1430-1480 cm-1 may be caused by aggregations of several species of fullerenes. If our speculation is correct, metamorphic diamond could have the possibility of preservation of intermediate carbon phases in diamond because the duration for diamond growth was much shorter than kimberlitic diamonds. We should pay attentions to such extra materials inside diamonds in order to clarify the real image of the diamond formation.

Development of a method for total inorganic arsenic analysis using anodic stripping voltammetry and a Au-coated, diamond thin-film electrode.

PubMed

Song, Yang; Swain, Greg M

2007-03-15

We demonstrate that a Au-coated, boron-doped, diamond thin-film electrode provides a sensitive, reproducible, and stable response for total inorganic arsenic (As(III) and As(V)) using differential pulse anodic stripping voltammetry (DPASV). As is preconcentrated with Au on the diamond surface during the deposition step and detected oxidatively during the stripping step. Au deposition was uniform over the electrode surface with a nominal particle size of 23 +/- 5 nm and a particle density of 109 cm-2. The electrode and method were used to measure the As(III) concentration in standard and river water samples. The detection figures of merit were compared with those obtained using conventional Au-coated glassy carbon and Au foil electrodes. The method was also used to determine the As(V) concentration in standard solutions after first being chemically reduced to As(III) with Na2SO3, followed by the normal DPASV determination of As(III). Sharp and symmetric stripping peaks were generally observed for the Au-coated diamond electrode. LODs were 0.005 ppb (S/N = 3) for As(III) and 0.08 ppb (S/N = 3) for As(V) in standard solutions. An As(III) concentration of 0.6 ppb was found in local river water. The relative standard deviation of the As stripping peak current for river water was 1.5% for 10 consecutive measurements and was less than 9.1% over a 10-h period. Excellent electrode response stability was observed even in the presence of up to 5 ppm of added humic acid. In summary, the Au-coated diamond electrode exhibited better performance for total inorganic As analysis than did Au-coated glassy carbon or Au foil electrodes. Clearly, the substrate on which the Au is supported influences the detection figures of merit.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pomorski, Michal; Mer-Calfati, Christine; Foulon, Francois

Diamond exhibits a combination of properties which makes it attractive for neutron detection in hostile conditions. In the particular case of detection in a nuclear reactor, it is resilient to radiation, exhibits a natural low sensitivity to gamma rays, and its small size (as compared with that of gas ionisation chambers) enables fluency monitoring with a high position resolution. We report here on the use of synthetic CVD diamond as a solid state micro-fission chamber with U-235 converting material for in-core thermal neutron monitoring. Two types of thin diamond detectors were developed for this application. The first type of detectormore » is fabricated using thin diamond membrane obtained by etching low-cost commercially available single crystal CVD intrinsic diamond, so called 'optical grade' material. Starting from a few hundred of micrometre thick samples, the sample is sliced with a laser and then plasma etched down to a few tenths of micrometre. Here we report the result obtained with a 17 μm thick device. The detection surface of this detector is equal to 1 mm{sup 2}. Detectors with surfaces up to 1 cm{sup 2} can be fabricated with this technique. The second type of detector is fabricated by growing successively two thin films of diamond, by the microwave enhanced chemical vapour deposition technique, on HPHT single crystal diamond. A first, a film of boron doped (p+) single crystal diamond, a few microns thick, is deposited. Then a second film of intrinsic diamond with a thickness of a few tens of microns is deposited. This results in a P doped, Intrinsic, Metal structure (PIM) structure in which the intrinsic volume id the active part of the detector. Here we report the results obtained with a 20 μm thick intrinsic whose detection surface is equal to 0.5 mm{sup 2}, with the possibility to enlarge the surface of the detector up to 1 cm{sup 2}. These two types of detector were tested at the VR-1 research reactor at the Czech Technical University in Prague. The Training Reactor VR-1 is a pool type (light water) reactor based on UO{sub 2} low enriched uranium. It has a nominal power of 1 kW, and can be operated for a short period up to 5 kW. The arrangement of the reactor pool reactor facilitates access to the core, setting and removal of various experimental samples and detectors, and safe and easy handling of fuel assemblies. The reactor is equipped with two horizontal channels (radial and tangential) and 10 vertical channels, of varying diameters, which can be loaded into various core positions, and one pneumatic transfer system. It is also equipped with several specifically designed educational instrumentation systems that can be used to supply complementary measurements and characterization around the reactor. The reactor is operated by the Department of Nuclear Reactors of the Faculty of Nuclear Sciences and Physical Engineering of the Czech Technical University in Prague. The two detectors were placed in-core through one of the vertical insertion channel. They were coupled to remote placed (5 m BNC cable) classical nuclear charge sensitive electronics. Detection properties of both sensors, including: pulse height spectra of U-235 fission fragments (response linearity with neutron flux, count rate, gamma background, were evaluated varying the power of the reactor from 0.005 W to 500 W. The evolution of the counting rate of the thinned optical grade detector as a function of counting rate of a gas ionization chamber used currently for reactor monitoring shows the very good linearity of the detector over the 5 decades. Similar results were obtained with the PIM detector. Additionally fast transient current signals of the detectors were recorded on a digital storage oscilloscope (DSO) using broad-band amplifier and with a simple bias-T, showing potential use of such sensors for neutron counting with no need of an amplification stage, since non-amplified signals from fission fragments exceeded 4 mV in amplitude. Therefore, one can think of simple neutron counting system by feeding diamond detectors signals directly to the low threshold discriminators. The results obtained on the VR1 will be described and discussed in detail in the paper and associated presentation. The results demonstrate that diamond micro-fission chambers can be used for in-core neutron monitoring, where robust, simple and compact devices are required.« less

Characterization of a quadrant diamond transmission X-ray detector including a precise determination of the mean electron–hole pair creation energy

DOE PAGES

Keister, Jeffrey W.; Cibik, Levent; Schreiber, Swenja; ...

2018-02-20

Precise monitoring of the incoming photon flux is crucial for many experiments using synchrotron radiation. For photon energies above a few keV, thin semiconductor photodiodes can be operated in transmission for this purpose. Diamond is a particularly attractive material as a result of its low absorption. The responsivity of a state-of-the art diamond quadrant transmission detector has been determined, with relative uncertainties below 1% by direct calibration against an electrical substitution radiometer. From these data and the measured transmittance, the thickness of the involved layers as well as the mean electron–hole pair creation energy were determined, the latter with anmore » unprecedented relative uncertainty of 1%. Lastly, the linearity and X-ray scattering properties of the device are also described.« less

Sticking non-stick: Surface and Structure control of Diamond-like Carbon in Plasma Enhanced Chemical Vapour Deposition

NASA Astrophysics Data System (ADS)

Jones, B. J.; Nelson, N.

2016-10-01

This short review article explores the practical use of diamond-like carbon (DLC) produced by plasma enhanced chemical vapour deposition (PECVD). Using as an example issues relating to the DLC coating of a hand-held surgical device, we draw on previous works using atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, tensiometry and electron paramagnetic resonance. Utilising data from these techniques, we examine the surface structure, substrate-film interface and thin film microstructure, such as sp2/sp3 ratio (graphitic/diamond-like bonding ratio) and sp2 clustering. We explore the variations in parameters describing these characteristics, and relate these to the final device properties such as friction, wear resistance, and diffusion barrier integrity. The material and device characteristics are linked to the initial plasma and substrate conditions.

Characterization of a quadrant diamond transmission X-ray detector including a precise determination of the mean electron–hole pair creation energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keister, Jeffrey W.; Cibik, Levent; Schreiber, Swenja

Precise monitoring of the incoming photon flux is crucial for many experiments using synchrotron radiation. For photon energies above a few keV, thin semiconductor photodiodes can be operated in transmission for this purpose. Diamond is a particularly attractive material as a result of its low absorption. The responsivity of a state-of-the art diamond quadrant transmission detector has been determined, with relative uncertainties below 1% by direct calibration against an electrical substitution radiometer. From these data and the measured transmittance, the thickness of the involved layers as well as the mean electron–hole pair creation energy were determined, the latter with anmore » unprecedented relative uncertainty of 1%. Lastly, the linearity and X-ray scattering properties of the device are also described.« less

Novel factor VIII variants with a modified furin cleavage site improve the efficacy of gene therapy for hemophilia A.

PubMed

Nguyen, G N; George, L A; Siner, J I; Davidson, R J; Zander, C B; Zheng, X L; Arruda, V R; Camire, R M; Sabatino, D E

2017-01-01

Essentials Factor (F) VIII is an inefficiently expressed protein. Furin deletion FVIII variants were purified and characterized using in vitro and in vivo assays. These minimally modified novel FVIII variants have enhanced function. These variants provide a strategy for increasing FVIII expression in hemophilia A gene therapy. Background The major challenge for developing gene-based therapies for hemophilia A is that human factor VIII (hFVIII) has intrinsic properties that result in inefficient biosynthesis. During intracellular processing, hFVIII is predominantly cleaved at a paired basic amino acid cleaving enzyme (PACE) or furin cleavage site to yield a heterodimer that is the major form of secreted protein. Previous studies with B-domain-deleted (BDD) canine FVIII and hFVIII-R1645H, both differing from hFVIII by a single amino acid at this site, suggested that these proteins are secreted mainly in a single polypeptide chain (SC) form and exhibit enhanced function. Objective We hypothesized that deletion(s) of the furin site modulates FVIII biology and may enhance its function. Methods A series of recombinant hFVIII-furin deletion variants were introduced into hFVIII-BDD [Δ1645, 1645-46(Δ2), 1645-47(Δ3), 1645-48(Δ4), or Δ1648] and characterized. Results In vitro, recombinant purified Δ3 and Δ4 were primarily SC and, interestingly, had 2-fold higher procoagulant activity compared with FVIII-BDD. In vivo, the variants also have improved hemostatic function. After adeno-associated viral (AAV) vector delivery, the expression of these variants is 2-4-fold higher than hFVIII-BDD. Protein challenges of each variant in mice tolerant to hFVIII-BDD showed no anti-FVIII immune response. Conclusions These data suggest that the furin deletion hFVIII variants are superior to hFVIII-BDD without increased immunogenicity. In the setting of gene-based therapeutics, these novel variants provide a unique strategy to increase FVIII expression, thus lowering the vector dose, a critical factor for hemophilia A gene therapy. © 2016 The Authors. Journal of Thrombosis and Haemostasis published by Wiley Periodicals, Inc. on behalf of International Society on Thrombosis and Haemostasis.

Synchrotron X-ray Microdiffraction Analysis of Proton Irradiated Polycrystalline Diamond Films

NASA Technical Reports Server (NTRS)

Newton, R. I.; Davidson, J. L.; Ice, G. E.; Liu, W.

2004-01-01

X-ray microdiffraction is a non-destructive technique that allows for depth-resolved, strain measurements with sub-micron spatial resolution. These capabilities make this technique promising for understanding the mechanical properties of MicroElectroMechanical Systems (MEMS). This investigation examined the local strain induced by irradiating a polycrystalline diamond thin film with a dose of 2x10(exp 17) H(+)per square centimeter protons. Preliminary results indicate that a measurable strain, on the order of 10(exp -3), was introduced into the film near the End of Range (EOR) region of the protons.

Predisposing Factors of Liver Necrosis after Transcatheter Arterial Chemoembolization in Liver Metastases from Neuroendocrine Tumor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joskin, Julien, E-mail: j.joskin@gmail.com; Baere, Thierry de, E-mail: Thierry.DEBAERE@igr.fr; Auperin, Anne, E-mail: Anne.AUPERIN@igr.fr

PurposeTo investigate predictive factors for liver necrosis after transcatheter arterial chemoembolization (TACE) of neuroendocrine liver metastases.MethodsA total of 164 patients receiving 374 TACE were reviewed retrospectively to analyze predictive factors of liver necrosis. We analyzed patient age and sex; metastasis number and location; percentage of liver involvement; baseline liver function test; and pretreatment imaging abnormalities such as bile duct dilatation (BDD), portal vein narrowing (PVN), and portal vein thrombosis (PVT). We analyzed TACE technique such as Lipiodol or drug-eluting beads (DEB) as the drug’s vector; dose of chemotherapy; diameter of DEB; and number, frequency, and selectivity of TACE.ResultsLiver necrosis developedmore » after 23 (6.1 %) of 374 TACE. In multivariate analysis, DEB > 300 μm in size induced more liver necrosis compared to Lipiodol (odds ratio [OR] 35.20; p < 0.0001) or with DEB < 300 μm in size (OR 19.95; p < 0.010). Pretreatment BDD (OR 119.64; p < 0.0001) and PVT (OR 9.83; p = 0.030) were predictive of liver necrosis. BDD or PVT responsible for liver necrosis were present before TACE in 59 % (13 of 22) and were induced by a previous TACE in 41 % (9 of 22) of cases.ConclusionDEB > 300 μm in size, BDD, and PVT are responsible for increased rate of liver necrosis after TACE. Careful analysis of BDD or PVT on pretreatment images as well as images taken between two courses can help avoid TACE complications.« less

Highly efficient and mild electrochemical mineralization of long-chain perfluorocarboxylic acids (C9-C10) by Ti/SnO2-Sb-Ce, Ti/SnO2-Sb/Ce-PbO2, and Ti/BDD electrodes.

PubMed

Lin, Hui; Niu, Junfeng; Xu, Jiale; Huang, Haiou; Li, Duo; Yue, Zhihan; Feng, Chenghong

2013-11-19

The electrochemical mineralization of environmentally persistent long-chain perfluorinated carboxylic acids (PFCAs), i.e., perfluorononanoic acid (C8F17COOH, PFNA) and perfluorodecanoic acid (C9F19COOH, PFDA) was investigated in aqueous solutions (0.25 mmol L(-1)) over Ti/SnO2-Sb-Ce (SnO2), Ti/SnO2-Sb/Ce-PbO2 (PbO2), and Ti/BDD (BDD) anodes under galvanostatic control at room temperature. Based on PFCA decay rate, total organic carbon (TOC) reduction, defluorination ratio, safety, and energy consumption, the performance of PbO2 electrode was comparable with that of BDD electrode. After 180 min electrolysis, the PFNA removals on BDD and PbO2 electrodes were 98.7 ± 0.4% and 97.1 ± 1.0%, respectively, while the corresponding PFDA removals were 96.0 ± 1.4% and 92.2 ± 1.9%. SnO2 electrode yielded lower PFCA removals and led to notable secondary pollution by Sb ions. The primary mineralization product, F(-), as well as trace amounts of intermediate PFCAs with shortened chain lengths, were detected in aqueous solution after electrolysis. On the basis of these results, a degradation mechanism including three potential routes is proposed: via formation of short-chain PFCAs by stepwise removal of CF2; direct mineralization to CO2 and HF; conversion to volatile fluorinated organic compounds. The results presented here demonstrate that electrochemical technique exhibits high efficiency in mineralizing PFNA and PFDA under mild conditions, and is promising for the treatment of long-chain PFCAs in wastewater.

Optical Characterization of Pulse Laser Deposition of Thin Films of Hard Materials Using RHEED and AFM Techniques

DTIC Science & Technology

2011-12-20

diamond thin-film generation. PLD is initiated by laser ablation, which is essentially evaporation of a material by a high - powered laser. Subsequently...COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d...PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION

Laser Deposition of Polymer Nanocomposite Thin Films and Hard Materials and Their Optical Characterization

DTIC Science & Technology

2013-12-05

visible light on instruments such as microscope tips and micro- surgical tools. Hard carbon known as diamond-like carbon films produced by pulsed laser ...visible (610 nm) LED source and a supplemental infra-red 980-nm laser diode (for the studies of the upconversion fluorescence). The basic package...5/2013 Final Performance Report 15 Sep 2012- 14 Sep 2013 LASER DEPOSITION OF POLYMER NANOCOMPOSITE THIN FILMS AND HARD MATERIALS AND THEIR OPTICAL

U.S. DOE Office of Science Success Stories (2011)

Science.gov Websites

; Gibson, Kerry; ACC0400 2011-04-01; Thin Sheet of Diamond Has Worlds of Uses; Sagoff, Jared; ACC0399 Top -03-28; Firm Uses DOE's Fastest Supercomputer to Streamline Long-Haul Trucks; ACC0391 2011-03-28

Ion Beam Analysis Of Nitrogen Incorporated Ultrananocrystalline Diamond (UNCD) Thin Films

NASA Astrophysics Data System (ADS)

AlFaify, S.; Garratt, E.; Dissanayake, A.; Mancini, D. C.; Kayani, A.

2011-06-01

Determination of the elemental composition is important to correlate the properties of nitrogen incorporated Ultrananocrystalline Diamond (UNCD) thin films with their growth conditions. Films were deposited by CVD deposition technology and nitrogen incorporation was introduced by diluting the growth Ar/CH4 plasma with N2 gas. Deposition of UNCD thin films was carried out on tungsten (˜15 nm) coated Si substrates with varying concentrations of N2 diluted to the growth plasma. Scanning electron microscopy (SEM) and Raman spectroscopy (RS) were used to confirm the characteristic morphology of the UNCD film and its dominant sp3 bonding respectively. The deposited films were smooth on the submicron scale with the RMS roughness value of 2.9-5.1 nm. Reflectometry spectroscopy analysis (RES) technique was used to measure the films thicknesses. To obtain the elemental composition of the UNCD thin films, Rutherford Backscattering Spectrometry (RBS), Non-Rutherford Backscattering Spectrometry (NRBS), Elastic Recoil Detection Analysis (ERDA) and Nuclear Reaction Analysis (NRA) were performed. Deposited UNCD films contained less than 5 at.% of H while N content incorporated in the films was estimated to be lower than 1 at.%. The intermixing region between the substrate and the film was found to be negligible. Moreover, amorphous phase as determined by Raman analysis was found to be increasing for the sample deposited with N2.

The improvement of SiO2 nanotubes electrochemical behavior by hydrogen atmosphere thermal treatment

NASA Astrophysics Data System (ADS)

Spataru, Nicolae; Anastasescu, Crina; Radu, Mihai Marian; Balint, Ioan; Negrila, Catalin; Spataru, Tanta; Fujishima, Akira

2018-06-01

Highly defected SiO2 nanotubes (SiO2-NT) were obtained by a simple sol-gel procedure followed by calcination. Boron-doped diamond (BDD) polycrystalline films coated with SiO2-NT were used as working electrodes and, unexpectedly, cyclic voltammetric experiments have shown that the concentration of both positive and negative defects at the surface is high enough to enable redox processes involving positively charged Ru(bpy)32+/3+ to occur. Conversely, no electrochemical activity was put into evidence for Fe(CN)63-/4- species, most likely as a result of the strong electrostatic repulsion exerted by the negatively charged SiO2 surface. The concentration of surface defects was further increased by a subsequent thermal treatment in a hydrogen atmosphere which, as EIS measurements have shown, significantly promotes Ru(bpy)32+ anodic oxidation. Digital simulation of the voltammetric responses demonstrated that this treatment does not lead to a similar increase of the number of electron-donor sites. It was also found that methanol anodic oxidation at hydrogenated SiO2-NT-supported platinum results in Tafel slopes of 116-220 mV decade-1, comparable to those reported for both conventional PtRu and Pt-oxide catalysts.

Accept, distract, or reframe? An exploratory experimental comparison of strategies for coping with intrusive body image thoughts in anorexia nervosa and body dysmorphic disorder.

PubMed

Hartmann, Andrea S; Thomas, Jennifer J; Greenberg, Jennifer L; Rosenfield, Elizabeth H; Wilhelm, Sabine

2015-02-28

Negative body image is the hallmark of anorexia nervosa (AN) and body dysmorphic disorder (BDD). One aspect of body image, appearance-related thoughts, have shown to be a major contributor to relapse, thus further investigation of successful treatment strategies targeting these maladaptive thoughts are warranted. The present study tested an acceptance/mindfulness (AC), a cognitive restructuring (CR), and a distraction strategy with regard to their short-term effectiveness of reducing the frequency of thought occurrence and associated outcomes in participants with AN (n=20), BDD (n=21), and healthy controls (HC; n=22). Although all strategies led to a significant reduction of thought frequency, there was no group × strategy interaction effect in their reduction. Positive affect increased in the BDD group through the AC strategy, but decreased in healthy controls. Acceptance of the thought increased in the CR strategy in AN, whereas that strategy seemed to work least for BDD. Healthy controls showed most acceptance when using distraction. Taken together, the study suggests that all strategies might have their benefits and that it might be worthwhile further investigating differential indication of the strategies with regard to diagnosis and individual factors. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders

NASA Astrophysics Data System (ADS)

Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

2016-11-01

Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders.

PubMed

Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

2016-11-21

Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds' Glx, Cho, Cr in the ACC and HCs' mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds' Glx and Cr in the PC and HCs' mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

Monte Carlo modelling the dosimetric effects of electrode material on diamond detectors.

PubMed

Baluti, Florentina; Deloar, Hossain M; Lansley, Stuart P; Meyer, Juergen

2015-03-01

Diamond detectors for radiation dosimetry were modelled using the EGSnrc Monte Carlo code to investigate the influence of electrode material and detector orientation on the absorbed dose. The small dimensions of the electrode/diamond/electrode detector structure required very thin voxels and the use of non-standard DOSXYZnrc Monte Carlo model parameters. The interface phenomena was investigated by simulating a 6 MV beam and detectors with different electrode materials, namely Al, Ag, Cu and Au, with thickens of 0.1 µm for the electrodes and 0.1 mm for the diamond, in both perpendicular and parallel detector orientation with regards to the incident beam. The smallest perturbations were observed for the parallel detector orientation and Al electrodes (Z = 13). In summary, EGSnrc Monte Carlo code is well suited for modelling small detector geometries. The Monte Carlo model developed is a useful tool to investigate the dosimetric effects caused by different electrode materials. To minimise perturbations cause by the detector electrodes, it is recommended that the electrodes should be made from a low-atomic number material and placed parallel to the beam direction.

Liquid impact and fracture of free-standing CVD diamond

NASA Astrophysics Data System (ADS)

Kennedy, Claire F.; Telling, Robert H.; Field, John E.

1999-07-01

The Cavendish Laboratory has developed extensive facilities for studies of liquid and solid particle erosion. This paper describes the high-speed liquid impact erosion of thin CVD diamond discs and the variation with grain sizes of the absolute damage threshold velocity (ADTV), viz., the threshold below which the specimen shows no damage. All specimens fail by rear surface cracking and there is shown to be a shallow dependence of rear surface ADTV on grain size. Fracture propagation in CVD diamond has also been monitored using a specially-designed double-torsion apparatus and data for K1C are presented. Tentatively, the results suggest that finer-grained CVD diamond exhibits a higher fracture toughness, although the differences are slight even over a fourfold variation in the mean grain size. No preference for intergranular fracture was observed and one may conclude from this that the grain boundaries themselves do not seriously weaken the material. The large pre-existing flaws, both within and between grains, whose size varies the grain size are believed to be the dominant source of weakness.

Prediction of Performance of Diamond Wire Saw with Respect to Texture Characteristics of Rock / Prognozowanie Wydajności Pracy Strunowej Piły Diamentowej W Odniesieniu Do Charakterystyki Tekstury Skał

NASA Astrophysics Data System (ADS)

Ghaysari, N.; Ataei, M.; Sereshki, F.; Mikaiel, R.

2012-12-01

In this study, prediction of production rate in diamond wire saw has been investigated. Performance measurements of diamond wire saw carried out in 7 different quarries of carbonate rocks in Iran. For determination textural properties, rock samples were collected from these quarries. At first, a thin section was prepared for each rock and then 5 digital photographs were taken from each section. After this, all images were digitized using AutoCAD software. Then, area, perimeter, longest diameter and shortest diameter were assigned. According to these parameters, all of the other textural characteristics and texture coefficient were determined too. The correlation between sawing rate and textural characteristics were evaluated using multiple and simple regression analyses. Then developed model was validated by P-value test. It was concluded that area, perimeter, diameter equivalent and index of grain size homogeneity are very effective on production rate. Production rate using diamond wire saw can reliably be predicted using developed model.

Surface characteristics and damage distributions of diamond wire sawn wafers for silicon solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sopori, Bhushan; Devayajanam, Srinivas; Basnyat, Prakash

2016-01-01

This paper describes surface characteristics, in terms of its morphology, roughness and near-surface damage of Si wafers cut by diamond wire sawing (DWS) of Si ingots under different cutting conditions. Diamond wire sawn Si wafers exhibit nearly-periodic surface features of different spatial wavelengths, which correspond to kinematics of various movements during wafering, such as ingot feed, wire reciprocation, and wire snap. The surface damage occurs in the form of frozen-in dislocations, phase changes, and microcracks. The in-depth damage was determined by conventional methods such as TEM, SEM and angle-polishing/defect-etching. However, because these methods only provide local information, we have alsomore » applied a new technique that determines average damage depth over a large area. This technique uses sequential measurement of the minority carrier lifetime after etching thin layers from the surfaces. The lateral spatial damage variations, which seem to be mainly related to wire reciprocation process, were observed by photoluminescence and minority carrier lifetime mapping. Our results show a strong correlation of damage depth on the diamond grit size and wire usage.« less

Multi-level diffractive optics for single laser exposure fabrication of telecom-band diamond-like 3-dimensional photonic crystals.

PubMed

Chanda, Debashis; Abolghasemi, Ladan E; Haque, Moez; Ng, Mi Li; Herman, Peter R

2008-09-29

We present a novel multi-level diffractive optical element for diffractive optic near-field lithography based fabrication of large-area diamond-like photonic crystal structure in a single laser exposure step. A multi-level single-surface phase element was laser fabricated on a thin polymer film by two-photon polymerization. A quarter-period phase shift was designed into the phase elements to generate a 3D periodic intensity distribution of double basis diamond-like structure. Finite difference time domain calculation of near-field diffraction patterns and associated isointensity surfaces are corroborated by definitive demonstration of a diamond-like woodpile structure formed inside thick photoresist. A large number of layers provided a strong stopband in the telecom band that matched predictions of numerical band calculation. SEM and spectral observations indicate good structural uniformity over large exposure area that promises 3D photonic crystal devices with high optical quality for a wide range of motif shapes and symmetries. Optical sensing is demonstrated by spectral shifts of the Gamma-Zeta stopband under liquid emersion.

Cu incorporated amorphous diamond like carbon (DLC) composites: An efficient electron field emitter over a wide range of temperature

NASA Astrophysics Data System (ADS)

Ahmed, Sk Faruque; Alam, Md Shahbaz; Mukherjee, Nillohit

2018-03-01

The effect of temperature on the electron field emission properties of copper incorporated amorphous diamond like carbon (a-Cu:DLC) thin films have been reported. The a-Cu:DLC thin films have been deposited on indium tin oxide (ITO) coated glass and silicon substrate by the radio frequency sputtering process. The chemical composition of the films was investigated using X-ray photoelectron spectroscopy and the micro structure was established using high resolution transmission electron microscopy. The sp2 and sp3 bonding ratio in the a-Cu:DLC have been analyzed by the Fourier transformed infrared spectroscopy studies. The material showed excellent electron field emission properties; which was optimized by varying the copper atomic percentage and temperature of the films. It was found that the threshold field and effective emission barrier were reduced significantly by copper incorporation as well as temperature and a detailed explanation towards emission mechanism has been provided.

Use of valence band Auger electron spectroscopy to study thin film growth: oxide and diamond-like carbon films

NASA Astrophysics Data System (ADS)

Steffen, H. J.

1994-12-01

It is demonstrated how Auger line shape analysis with factor analysis (FA), least-squares fitting and even simple peak height measurements may provide detailed information about the composition, different chemical states and also defect concentration or crystal order. Advantage is taken of the capability of Auger electron spectroscopy to give valence band structure information with high surface sensitivity and the special aspect of FA to identify and discriminate quantitatively unknown chemical species. Valence band spectra obtained from Ni, Fe, Cr and NiFe40Cr20 during oxygen exposure at room temperature reveal the oxidation process in the initial stage of the thin layer formation. Furthermore, the carbon chemical states that were formed during low energy C(+) and Ne(+) ion irradiation of graphite are delineated and the evolution of an amorphous network with sp3 bonds is disclosed. The analysis represents a unique method to quantify the fraction of sp3-hybridized carbon in diamond-like materials.

Peculiarities of both light and beta-particles scattering by ultrathin diamond-like semiconductor film.

PubMed

Rumyantsev, Vladimir V; Shtaerman, Esfir Y

2008-02-01

Peculiarities of scattering of TM-polarized light wave by a diamond-like crystalline nano-layer are studied. They are due to specific dispersion of n-phonon polaritons localized in the layer. The IR polaritons discussed here (relating to diamond and Si crystals which are nonpolar materials) will only appear if some of the vibration modes become polar, e.g., due to the presence of the surface. As a result of mixing of g- and u-modes of ion oscillations along the (111)-direction in the near-surface layer, it is possible to observe additional (with respect to bulk) scattering of coherent electromagnetic waves of the Stokes and anti-Stokes frequencies. beta-particles can be utilized as an independent tool of study of new semiconductors, in particular thin diamond films. The effect associated with response of a quasi-two-dimensional diamond-like layer to the moving electron field is considered. beta-particle field induces phonon excitation modes to arise in the material. Coupled with the beta-particle electromagnetic modes they generate polaritons. Spectral density of the radiation intensity of the flashed phonon polaritons has been estimated as a function of the layer thickness as well as of the scattering angle and the beta-particle velocity.