Very High Quality Crystals of Wide-Gap II-VI Semiconductors: What for?
2001-01-01
the reciprocal space mapping , by the etch pit density (EPD) measurements (to determine the density of dislocations) and by the measurement of the width...crystals. The EPD was in the range 5 x 1 + 104 cmn2 for Cdl.,ZnxTe crystals and about 104 cmz for ZnTe. The reciprocal space mapping of the crystals
Metalorganic vapor phase epitaxy of AlN on sapphire with low etch pit density
NASA Astrophysics Data System (ADS)
Koleske, D. D.; Figiel, J. J.; Alliman, D. L.; Gunning, B. P.; Kempisty, J. M.; Creighton, J. R.; Mishima, A.; Ikenaga, K.
2017-06-01
Using metalorganic vapor phase epitaxy, methods were developed to achieve AlN films on sapphire with low etch pit density (EPD). Key to this achievement was using the same AlN growth recipe and only varying the pre-growth conditioning of the quartz-ware. After AlN growth, the quartz-ware was removed from the growth chamber and either exposed to room air or moved into the N2 purged glove box and exposed to H2O vapor. After the quartz-ware was exposed to room air or H2O, the AlN film growth was found to be more reproducible, resulting in films with (0002) and (10-12) x-ray diffraction (XRD) rocking curve linewidths of 200 and 500 arc sec, respectively, and EPDs < 100 cm-2. The EPD was found to correlate with (0002) linewidths, suggesting that the etch pits are associated with open core screw dislocations similar to GaN films. Once reproducible AlN conditions were established using the H2O pre-treatment, it was found that even small doses of trimethylaluminum (TMAl)/NH3 on the quartz-ware surfaces generated AlN films with higher EPDs. The presence of these residual TMAl/NH3-derived coatings in metalorganic vapor phase epitaxy (MOVPE) systems and their impact on the sapphire surface during heating might explain why reproducible growth of AlN on sapphire is difficult.
NASA Astrophysics Data System (ADS)
Özden, Selin; Koc, Mumin Mehmet
2018-03-01
CdTe epitaxial thin films, for use as a buffer layer for HgCdTe defectors, were grown on GaAs (211)B using the molecular beam epitaxy method. Wet chemical etching (Everson method) was applied to the epitaxial films using various concentrations and application times to quantify the crystal quality and dislocation density. Surface characterization of the epitaxial films was achieved using Atomic force microscopy and Scanning electron microscopy (SEM) before and after each treatment. The Energy Dispersive X-Ray apparatus of SEM was used to characterize the chemical composition. Untreated CdTe films show smooth surface characteristics with root mean square (RMS) roughnesses of 1.18-3.89 nm. The thicknesses of the CdTe layers formed were calculated via FTIR spectrometry and obtained by ex situ spectroscopic ellipsometry. Raman spectra were obtained for various temperatures. Etch pit densities (EPD) were measured, from which it could be seen that EPD changes between 1.7 × 108 and 9.2 × 108 cm-2 depending on the concentration of the Everson etch solution and treatment time. Structure, shape and depth of pits resulting from each etch pit implementation were also evaluated. Pit widths varying between 0.15 and 0.71 µm with heights varying between 2 and 80 nm were observed. RMS roughness was found to vary by anything from 1.56 to 26 nm.
Effect of Annealing on the Density of Defects in Epitaxial CdTe (211)/GaAs
NASA Astrophysics Data System (ADS)
Bakali, Emine; Selamet, Yusuf; Tarhan, Enver
2018-05-01
CdTe thin films were grown on GaAs (211) wafers by molecular beam epitaxy as the buffer layer for HgCdTe infrared detector applications. We studied the effect of annealing on the density of dislocation of these CdTe thin films under varying annealing parameters such as annealing temperature, annealing duration, and number of cycles. Annealings were carried out using a homemade annealing reactor possessing a special heater element made of a Si wafer for rapid heating. The density of dislocations, which were made observable with a scanning electron microscope after etching with an Everson solution, were calculated by counting the number of dislocations per unit surface area, hence the term etch pit density (EPD). We were able to decrease EPD values by one order of magnitude after annealing. For example, the best EPD value after a 20-min annealing at 400°C was ˜ 2 × 107 cm-2 for a 1.63-μm CdTe thin film which was about 9.5 × 107 cm-2 before annealing. We also employed Raman scattering measurements to see the changes in the structural quality of the samples. From the Raman measurements, we were able to see improvements in the quality of our samples from the annealing by studying the ratio of 2LO/LO phonon mode Raman intensities. We also observed a clear decrease in the intensity of Te precipitations-related modes, indicating a decrease in the size and number of these precipitations.
NASA Astrophysics Data System (ADS)
Schulte, K. L.; Zutter, B. T.; Wood, A. W.; Babcock, S. E.; Kuech, T. F.
2014-03-01
Thick InxGa1-xAs metamorphic buffer layers (MBLs) grown by hydride vapor phase epitaxy (HVPE) were studied. Relationships between MBL properties and growth parameters such as grading rate, cap layer thickness, final xInAs, and deposition temperature (TD) were explored. The MBLs were characterized by measurement of in-plane residual strain (ɛ¦¦), surface etch pit density (EPD), and surface roughness. Capping layer thickness had a strong effect on strain relaxation, with thickly capped samples exhibiting the lowest ɛ¦¦. EPD was higher in samples with thicker caps, reflecting their increased relaxation through dislocation generation. ɛ¦¦ and EPD were weakly affected by the grading rate, making capping layer thickness the primary structural parameter which controls these properties. MBLs graded in discrete steps had similar properties to MBLs with continuous grading. In samples with identical thickness and 10-step grading style, ɛ¦¦ increased almost linearly with final xInAs, while total relaxation stayed relatively constant. Relaxation as a function of xInAs could be described by an equilibrium model in which dislocation nucleation is impeded by the energy of the existing dislocation array. EPD was constant from xInAs = 0 to 0.24 then increased exponentially, which is related to the increased dislocation interaction and blocking seen at higher dislocation densities. RMS roughness increased with xInAs above a certain strain rate (0.15%/µm) samples grown below this level possessed large surface hillocks and high roughness values. The elimination of hillocks at higher values of xInAs is attributed to increased density of surface steps and is related to the out-of-plane component of the burgers vector of the dominant type of 60° dislocation. TD did not affect ɛ¦¦ for samples with a given xInAs. EPD tended to increase with TD, indicating dislocation glide likely is impeded at higher temperatures.
Evaluation of four inch diameter VGF-Ge substrates used for manufacturing multi-junction solar cell
NASA Astrophysics Data System (ADS)
Kewei, Cao; Tong, Liu; Jingming, Liu; Hui, Xie; Dongyan, Tao; Youwen, Zhao; Zhiyuan, Dong; Feng, Hui
2016-06-01
Low dislocation density Ge wafers grown by a vertical gradient freeze (VGF) method used for the fabrication of multi-junction photovoltaic cells (MJC) have been studied by a whole wafer scale measurement of the lattice parameter, X-ray rocking curves, etch pit density (EPD), impurities concentration, minority carrier lifetime and residual stress. Impurity content in the VGF-Ge wafers, including that of B, is quite low although B2O3 encapsulation is used in the growth process. An obvious difference exists across the whole wafer regarding the distribution of etch pit density, lattice parameter, full width at half maximum (FWHM) of the X-ray rocking curve and residual stress measured by Raman spectra. These are in contrast to a reference Ge substrate wafer grown by the Cz method. The influence of the VGF-Ge substrate on the performance of the MJC is analyzed and evaluated by a comparison of the statistical results of cell parameters. Project supported by the National Natural Science Foundation of China (No. 61474104).
NASA Astrophysics Data System (ADS)
Reddy, M.; Peterson, J. M.; Lofgreen, D. D.; Vang, T.; Patten, E. A.; Radford, W. A.; Johnson, S. M.
2010-07-01
This paper describes molecular-beam epitaxy growth of mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) dual-band device structures on large-area (6 cm × 6 cm) CdZnTe substrates. Wafer-level composition and defect mapping techniques were used to investigate the limiting mechanisms in improving the cutoff wavelength ( λ c) uniformity and reducing the defect density. Structural quality of epitaxial layers was monitored using etch pit density (EPD) measurements at various depths in the epitaxial layers. Finally, 640 × 480, 20- μm-pixel-pitch dual-band focal-plane arrays (FPAs) were fabricated to demonstrate the overall maturity of growth and fabrication processes of epitaxial layers. The MWIR/LWIR dual-band layers, at optimized growth conditions, show a λ c variation of ±0.15 μm across a 6 cm × 6 cm CdZnTe substrate, a uniform low macrodefect density with an average of 1000 cm-2, and an average EPD of 1.5 × 105 cm-2. FPAs fabricated using these layers show band 1 (MWIR) noise equivalent temperature difference (NETD) operability of 99.94% and band 2 (LWIR) NETD operability of 99.2%, which are among the highest reported to date.
NASA Astrophysics Data System (ADS)
Lin, Jyun-Hao; Huang, Shyh-Jer; Su, Yan-Kuin
2014-01-01
A simple thermal cycle annealing (TCA) process was used to improve the quality of GaN grown on a Si substrate. The X-ray diffraction (XRD) and etch pit density (EPD) results revealed that using more process cycles, the defect density cannot be further reduced. However, the performance of GaN-based metal-semiconductor-metal (MSM) photodiodes (PDs) prepared on Si substrates showed significant improvement. With a two-cycle TCA process, it is found that the dark current of the device was only 1.46 × 10-11 A, and the photo-to-dark-current contrast ratio was about 1.33 × 105 at 5 V. Also, the UV/visible rejection ratios can reach as high as 1077.
NASA Technical Reports Server (NTRS)
Palosz, W.; Grasza, K.; Dudley, M.; Raghothamachar, B.; Cai, L.; Dunrose, K.; Halliday, D.; Boyall, N. M.; Rose, M. Franklin (Technical Monitor)
2001-01-01
To take a maximum advantage of materials processing in microgravity for understanding the effects of gravity, gravity-independent effects should be minimized. In crystal growth, the quality of the grown crystals may depend, among other factors, on their interaction with the walls of the processing container during and after growth, and on the rate of the crystal cool-down at the end of the process. To investigate the above phenomena, a series of CdTe crystal growth processes was carried out. The crystals were grown by physical vapor transport without contact with the side walls of the silica glass ampoules. To eliminate the effect of the seed quality, and to reduce the number of nuclei and related crystal grains, the Low Supersaturation Nucleation technique was applied. The source temperature was 930 C, the undercooling was a few degrees. The crystals, having the diameter of 25 mm, grew at the rate of a few mm per day. The post-growth cool-down to the room temperature was conducted at different rates, and lasted from a few minutes to four days. The crystals were characterized using chemical etching, low temperature luminescence, and Synchrotron White Beam X-ray Topography techniques. The dislocation (etch pit) density was measured and its distribution was analyzed by comparison with Poisson curves and with the Normalized Radial Distribution Correlation Function. In the regions where the crystal is in contact with silica, the materials show a considerable strain field which extends for a few mm or more from the silica-crystal interface. In the reference crystal grown with contact with the ampoule walls, and when the crystals are cooled at the highest rates, the etch pit/dislocation density is in the high 10(exp 5) per square centimeter region. Typical EPD values for lower cool-down rates are in the lower 10(exp 4) per square centimeter region. In some areas the actual dislocation density was about 10(exp 3) per square centimeter or even less. No apparent effect of the cool-down rate on polygonization was observed. Low temperature PL spectra show, that the dominant peak is (D(sup 0), h) and (A(sup 0), e) for samples with low and high dislocation densities, respectively. For low EPD crystals a peak at 1.45 eV with 21 meV phonon replicas was observed and attributed to donor-acceptor pair to neutral copper-acceptor transition. In high EPD crystals this PL structure was not observed, apparently due to the masking effect of the strong contribution from the dislocation band.
NASA Astrophysics Data System (ADS)
Wan, Xin; Xiong, Chao; Rodriguez-Zuluaga, Juan; Kervalishvili, Guram N.; Stolle, Claudia; Wang, Hui
2018-04-01
In this study, we developed an autodetection technique for the equatorial plasma depletions (EPDs) and their occurrence and depletion amplitudes based on in situ electron density measurements gathered by Swarm A satellite. For the first time, comparisons are made among the detected EPDs and their amplitudes with the loss of Global Positioning System (GPS) signal of receivers onboard Swarm A, and the Swarm Level-2 product, Ionospheric Bubble Index (IBI). It has been found that the highest rate of EPD occurrence takes place generally between 2200 and 0000 magnetic local time (MLT), in agreement with the IBI. However, the largest amplitudes of EPD are detected earlier at about 1900-2100 MLT. This coincides with the moment of higher background electron density and the largest occurrence of GPS signal loss. From a longitudinal perspective, the higher depletion amplitude is always witnessed in spatial bins with higher background electron density. At most longitudes, the occurrence rate of postmidnight EPDs is reduced compared to premidnight ones; while more postmidnight EPDs are observed at African longitudes. CHAMP observations confirm this point regardless of high or low solar activity condition. Further by comparing with previous studies and the plasma vertical drift velocity from ROCSAT-1, we suggest that while the F region vertical plasma drift plays a key role in dominating the occurrence of EPDs during premidnight hours, the postmidnight EPDs are the combined results from the continuing of former EPDs and newborn EPDs, especially during June solstice. And these newborn EPDs during postmidnight hours seem to be less related to the plasma vertical drift.
LWIR HgCdTe Detectors Grown on Ge Substrates
NASA Astrophysics Data System (ADS)
Vilela, M. F.; Lofgreen, D. D.; Smith, E. P. G.; Newton, M. D.; Venzor, G. M.; Peterson, J. M.; Franklin, J. J.; Reddy, M.; Thai, Y.; Patten, E. A.; Johnson, S. M.; Tidrow, M. Z.
2008-09-01
Long-wavelength infrared (LWIR) HgCdTe p-on- n double-layer heterojunctions (DLHJs) for infrared detector applications have been grown on 100 mm Ge (112) substrates by molecular beam epitaxy (MBE). The objective of this current work was to grow our baseline p-on- n DLHJ detector structure (used earlier on Si substrates) on 100 mm Ge substrates in the 10 μm to 11 μm LWIR spectral region, evaluate the material properties, and obtain some preliminary detector performance data. Material characterization techniques included are X-ray rocking curves, etch pit density (EPD) measurements, compositional uniformity determined from Fourier-transform infrared (FTIR) transmission, and doping concentrations determined from secondary-ion mass spectroscopy (SIMS). Detector properties include resistance-area product (RoA), spectral response, and quantum efficiency. Results of LWIR HgCdTe detectors and test structure arrays (TSA) fabricated on both Ge and silicon (Si) substrates are presented and compared. Material properties demonstrated include X-ray full-width of half-maximum (FWHM) as low as 77 arcsec, typical etch pit densities in mid 106 cm-2 and wavelength cutoff maximum/minimum variation <2% across the full wafer. Detector characteristics were found to be nearly identical for HgCdTe grown on either Ge or Si substrates.
NASA Astrophysics Data System (ADS)
Shen, Xiaomeng
InAs/InAsSb type-II superlattices (T2SLs) can be considered as potential alternatives for conventional HgCdTe photodetectors due to improved uniformity, lower manufacturing costs with larger substrates, and possibly better device performance. This dissertation presents a comprehensive study on the structural, optical and electrical properties of InAs/InAsSb T2SLs grown by Molecular Beam Epitaxy. The effects of different growth conditions on the structural quality were thoroughly investigated. Lattice-matched condition was successfully achieved and material of exceptional quality was demonstrated. After growth optimization had been achieved, structural defects could hardly be detected, so different characterization techniques, including etch-pit-density (EPD) measurements, cathodoluminescence (CL) imaging and X-ray topography (XRT), were explored, in attempting to gain better knowledge of the sparsely distributed defects. EPD revealed the distribution of dislocation-associated pits across the wafer. Unfortunately, the lack of contrast in images obtained by CL imaging and XRT indicated their inability to provide any quantitative information about defect density in these InAs/InAsSb T2SLs. The nBn photodetectors based on mid-wave infrared (MWIR) and long-wave infrared (LWIR) InAs/InAsSb T2SLs were fabricated. The significant difference in Ga composition in the barrier layer coupled with different dark current behavior, suggested the possibility of different types of band alignment between the barrier layers and the absorbers. A positive charge density of 1.8 x 1017/cm3 in the barrier of MWIR nBn photodetector, as determined by electron holography, confirmed the presence of a potential well in its valence band, thus identifying type-II alignment. In contrast, the LWIR nBn photodetector was shown to have type-I alignment because no sign of positive charge was detected in its barrier. Capacitance-voltage measurements were performed to investigate the temperature dependence of carrier densities in a metal-oxide-semiconductor (MOS) structure based on MWIR InAs/InAsSb T2SLs, and a nBn structure based on LWIR InAs/InAsSb T2SLs. No carrier freeze-out was observed in either sample, indicating very shallow donor levels. The decrease in carrier density when temperature increased was attributed to the increased density of holes that had been thermally excited from localized states near the oxide/semiconductor interface in the MOS sample. No deep-level traps were revealed in deep-level transient spectroscopy temperature scans.
GaAs Substrates for High-Power Diode Lasers
NASA Astrophysics Data System (ADS)
Mueller, Georg; Berwian, Patrick; Buhrig, Eberhard; Weinert, Berndt
GaAs substrate crystals with low dislocation density (Etch-Pit Density (EPD) < 500,^-2) and Si-doping ( ~10^18,^-3) are required for the epitaxial production of high-power diode-lasers. Large-size wafers (= 3 mathrm{in} -> >=3,) are needed for reducing the manufacturing costs. These requirements can be fulfilled by the Vertical Bridgman (VB) and Vertical Gradient Freeze (VGF) techniques. For that purpose we have developed proper VB/VGF furnaces and optimized the thermal as well as the physico-chemical process conditions. This was strongly supported by extensive numerical process simulation. The modeling of the VGF furnaces and processes was made by using a new computer code called CrysVUN++, which was recently developed in the Crystal Growth Laboratory in Erlangen.GaAs crystals with diameters of 2 and 3in were grown in pyrolytic Boron Nitride (pBN) crucibles having a small-diameter seed section and a conical part. Boric oxide was used to fully encapsulate the crystal and the melt. An initial silicon content in the GaAs melt of c (melt) = 3 x10^19,^-3 has to be used in order to achieve a carrier concentration of n = (0.8- 2) x10^18,^-3, which is the substrate specification of the device manufacturer of the diode-laser. The EPD could be reduced to values between 500,^-2 and 50,^-2 with a Si-doping level of 8 x10^17 to 1 x10^18,^-3. Even the 3in wafers have rather large dislocation-free areas. The lowest EPDs ( <100,^-2) are achieved for long seed wells of the crucible.
NASA Astrophysics Data System (ADS)
Matsunaga, G.; Okabayashi, M.; Aiba, N.; Boedo, J. A.; Ferron, J. R.; Hanson, J. M.; Hao, G. Z.; Heidbrink, W. W.; Holcomb, C. T.; In, Y.; Jackson, G. L.; Liu, Y. Q.; Luce, T. C.; McKee, G. R.; Osborne, T. H.; Pace, D. C.; Shinohara, K.; Snyder, P. B.; Solomon, W. M.; Strait, E. J.; Turnbull, A. D.; Van Zeeland, M. A.; Watkins, J. G.; Zeng, L.; the DIII-D Team; the JT-60 Team
2013-12-01
In the wall-stabilized high-β plasmas in JT-60U and DIII-D, interactions between energetic particle (EP) driven modes (EPdMs) and edge localized modes (ELMs) have been observed. The interaction between the EPdM and ELM are reproducibly observed. Many EP diagnostics indicate a strong correlation between the distorted waveform of the EPdM and the EP transport to the edge. The waveform distortion is composed of higher harmonics (n ⩾ 2) and looks like a density snake near the plasma edge. According to statistical analyses, ELM triggering by the EPdMs requires a finite level of waveform distortion and pedestal recovery. ELM pacing by the EPdMs occurs when the repetition frequency of the EPdMs is higher than the natural ELM frequency. EPs transported by EPdMs are thought to contribute to change the edge stability.
NASA Astrophysics Data System (ADS)
Xiong, Chao; Xu, Jiyao; Wu, Kun; Yuan, Wei
2018-02-01
The lower pair satellites of Swarm mission, flying side-by-side and separated by 1.4° in longitude (about 150 km), usually observed equatorial plasma depletions (EPDs) showing quite different structures, and sometime even only one satellite observed EPD. In this study, we provided 6-h continuous observations of EPDs on the night of 23-24 September 2014, from an all-sky imager located at Fuke (geographic:19.5°N,109.1°E), south of China. From the airglow images the EPDs were found with longitudinal extensions of about 50 km and all tilted from northwest to southeast direction. We further checked the in situ electron density simultaneously measured by the Swarm lower pair satellites and found the differences of Swarm in situ electron densities explained well by the longitudinally thin structure of EPDs observed from the all-sky imager. During later periods the bifurcation and merging were observed by the airglow images, and it was the first time to report both processes in the evolution of one EPD. The bifurcation was first observed at the higher-latitude part, and then observed at lower latitudes of EPD. The subbranches generated through bifurcation showed even thinner longitudinal extension of about 20-30 km, and later the subbranches started to merge with each other, forming a really complicated mesh of depleted regions.
NASA Astrophysics Data System (ADS)
Kil, Yeon-Ho; Kang, Sukill; Jeong, Tae Soo; Shim, Kyu-Hwan; Kim, Dae-Jung; Choi, Yong-Dae; Kim, Mi Joung; Kim, Taek Sung
2018-05-01
The Ge1- x Sn x layers were grown by using rapid thermal chemical-vapor deposition (RTCVD) on boron-doped p-type Si (100) substrates with Sn compositions up to x = 0.83%. In order to obtain effect of the Sn composition on the structural and the optical characteristics, we utilized highresolution X-ray diffraction (HR-XRD), etch pit density (EPD), atomic force microscopy (AFM), Raman spectroscopy, and photocurrent (PC) spectra. The Sn compositions in the Ge1- x Sn x layers were found to be of x = 0.00%, 0.51%, 0.65%, and 0.83%. The root-mean-square (RMS) of the surface roughness of the Ge1- x Sn x layer increased from 2.02 nm to 3.40 nm as the Sn composition was increased from 0.51% to 0.83%, and EPD was on the order of 108 cm-2. The Raman spectra consist of only one strong peak near 300 cm-1, which is assigned to the Ge-Ge LO peaks and the Raman peaks shift to the wave number with increasing Sn composition. Photocurrent spectra show near energy band gap peaks and their peak energies decrease with increasing Sn composition due to band-gap bowing in the Ge1- x Sn x layer. An increase in the band gap bowing parameter was observed with increasing Sn composition.
Worsley, Marcus A; Baumann, Theodore F; Satcher, Joe H; Olson, Tammy Y; Kuntz, Joshua D; Rose, Klint A
2015-03-03
In one embodiment, an aerogel includes a layer of shaped particles having a particle packing density gradient in a thickness direction of the layer, wherein the shaped particles are characterized by being formed in an electrophoretic deposition (EPD) process using an impurity. In another embodiment, a method for forming a functionally graded porous nanostructure includes adding particles of an impurity and a solution to an EPD chamber, applying a voltage difference across the two electrodes of the EPD chamber to create an electric field in the EPD chamber, and depositing the material onto surfaces of the particles of the impurity to form shaped particles of the material. Other functionally graded materials and methods are described according to more embodiments.
Radio-Tomographic Images of Post-midnight Equatorial Plasma Depletions
NASA Astrophysics Data System (ADS)
Hei, M. A.; Bernhardt, P. A.; Siefring, C. L.; Wilkens, M.; Huba, J. D.; Krall, J.; Valladares, C. E.; Heelis, R. A.; Hairston, M. R.; Coley, W. R.; Chau, J. L.
2013-12-01
For the first time, post-midnight equatorial plasma depletions (EPDs) have been imaged in the longitude-altitude plane using radio-tomography. High-resolution (~10 km × 10 km) electron-density reconstructions were created from total electron content (TEC) data using an array of receivers sited in Peru and the Multiplicative Algebraic Reconstruction Technique (MART) inversion algorithm. TEC data were obtained from the 150 and 400 MHz signals transmitted by the CERTO beacon on the C/NOFS satellite. In-situ electron density data from the C/NOFS CINDI instrument and electron density profiles from the UML Jicamarca ionosonde were used to generate an initial guess for the MART inversion, and also to constrain the inversion process. Observed EPDs had widths of 100-1000 km, spacings of 300-900 km, and often appeared 'pinched off' at the bottom. Well-developed EPDs appeared on an evening with a very small (4 m/s) Pre-Reversal-Enhancement (PRE), suggesting that postmidnight enhancements of the vertical plasma drift and/or seeding-induced uplifts (e.g. gravity waves) were responsible for driving the Rayleigh-Taylor Instability into the nonlinear regime on this night. On another night the Jicamarca ISR recorded postmidnight (~0230 LT) Eastward electric fields nearly twice as strong as the PRE fields seven hours earlier. These electric fields lifted the whole ionosphere, including embedded EPDs, over a longitude range ~14° wide. CINDI detected a dawn depletion in exactly the area where the reconstruction showed an uplifted EPD. Strong Equatorial Spread-F observed by the Jicamarca ionosonde during receiver observation times confirmed the presence of ionospheric irregularities.
NASA Technical Reports Server (NTRS)
Palosz, W.; Grasza, K.; Dudley, M.; Raghothamachar, B.; Cai, L.; Durose, K.; Halliday, D.; Boyall, N. M.; Rose, M. Franklin (Technical Monitor)
2001-01-01
In crystal growth, the quality of the final material may depend, among other factors, on its interaction with the walls of the ampoule during and after the growth, and on the rate of the crystal cool-down at the end of ate the process. To investigate the above phenomena, a series of CdTe crystal growth processes was carried out, The crystals were grown by physical vapor transport without contact with the side walls of the silica glass ampoules, applying the Low Supersaturation Nucleation technique. The source temperature was 930 C, the undercooling was a few degrees. The crystals, having the diameter of 25 mm, grew at the rate of a few mm per day. The post-growth cool-down to the room temperature was conducted at different rates, and lasted from a few minutes to four days. The crystals were characterized using chemical etching low temperature luminescence, and Synchrotron White Beam X-ray Topography techniques. The dislocation (etch pit) density was measured and its distribution was analyzed by comparison with Poisson curves and with the Normalized Radial Distribution Correlation Function. It was found that the contact of the crystal with silica leads to a strain field and high (in the 105 sq cm range) dislocation (etch pit) density. Similar defect concentrations were found in crystals subjected to fast post-growth cool-down. Typical EPD values for lower cool-down rates and in regions not affected by wall interactions are in the lower 10(exp 4) sq cm range. In some areas the actual dislocation density was about 10(exp 3) sq cm or even less. No apparent effect of the cool-down rate on polygonization was observed. A fine structure could be discerned in low-temperature PL spectra of crystals with low dislocation density.
Haghbin, Amin; Liaghat, Gholamhossein; Arabi, Amir Masoud; Pol, Mohammad Hossein
2017-01-01
In this work, an electrophoretic deposition (EPD) technique has been used for deposition of carbon nanotubes (CNTs) on the surface of glass fiber textures (GTs) to increase the volume conductivity and the interlaminar shear strength (ILSS) of CNT/glass fiber-reinforced polymers (GFRPs) composites. Comprehensive experimental studies have been conducted to establish the influence of electric field strength, CNT concentration in EPD suspension, surface quality of GTs, and process duration on the quality of deposited CNT layers. CNT deposition increased remarkably when the surface of glass fibers was treated with coupling agents. Deposition of CNTs was optimized by measuring CNT’s deposition mass and process current density diagrams. The effect of optimum field strength on CNT deposition mass is around 8.5 times, and the effect of optimum suspension concentration on deposition rate is around 5.5 times. In the optimum experimental setting, the current density values of EPD were bounded between 0.5 and 1 mA/cm2. Based on the cumulative deposition diagram, it was found that the first three minutes of EPD is the effective deposition time. Applying optimized EPD in composite fabrication of treated GTs caused a drastic improvement on the order of 108 times in the volume conductivity of the nanocomposite laminate in comparison with simple GTs specimens. Optimized CNT deposition also enhanced the ILSS of hierarchical nanocomposites by 42%. PMID:28937635
The Effect of Temperature and Electric Field on a Quantum Pseudodot Qubit
NASA Astrophysics Data System (ADS)
Chen, Ying-Cong; Xiao, Jing-Lin
2018-02-01
The electron's probability density (EPD) and the oscillating period (OP) of an electron confined by a three-dimensional RbCl quantum pseudodot (QPD) are studied. Calculations are performed by employing variational method of Pekar type (VMPT) and the quantum statistics theory (QST).The influences of the temperature and electric field on the EPD and the OP of the RbCl QPD qubit have been derived in detail. According to the obtained results, it is observed that the EPD and the OP increase (decrease) with raising temperature at lower (higher) temperature region. They are decaying functions of the electric field.
Sullivan, K T; Zhu, C; Tanaka, D J; Kuntz, J D; Duoss, E B; Gash, A E
2013-02-14
This work combines electrophoretic deposition (EPD) with direct-ink writing (DIW) to prepare thin films of Al/CuO thermites onto patterned two- and three-dimensional silver electrodes. DIW was used to write the electrodes using a silver nanoparticle ink, and EPD was performed in a subsequent step to deposit the thermite onto the conductive electrodes. Unlike conventional lithographic techniques, DIW is a low-cost and versatile alternative to print fine-featured electrodes, and adds the benefit of printing self-supported three-dimensional structures. EPD provides a method for depositing the composite thermite only onto the conductive electrodes, and with controlled thicknesses, which provides fine spatial and mass control, respectively. EPD has previously been shown to produce well-mixed thermite composites which can pack to reasonably high densities without the need for any postprocessing. Homogeneous mixing is particularly important in reactive composities, where good mixing can enhance the reaction kinetics by decreasing the transport distance between the components. Several two- and three-dimensional designs were investigated to highlight the versatility of using DIW and EPD together. In addition to energetic applications, we anticipate that this combination of techniques will have a variety of other applications, which would benefit from the controlled placement of a thin film of one material onto a conductive architecture of a second material.
The Effect of Phonons in RbCl Quantum Pseudodot Qubits
NASA Astrophysics Data System (ADS)
Sun, Yong; Ding, Zhao-Hua; Xiao, Jing-Lin
2016-07-01
By employing the Pekar variational method, the eigenenergies and eigenfunctions of the ground and first-excited states are obtained in a strong electron-longitudinal optical (LO) phonon coupling RbCl quantum pseudodot (QPD). A single qubit can be realized in this two-level quantum system. The electron probability density (EPD) oscillates in the RbCl QPD with a certain period. The investigated results show that the EPD rises with raising the chemical potential of the two-dimensional electron gas and the zero point of the pseudoharmonic potential, whereas it decays with increasing the polaron radius. However, the oscillating period (OP) possesses precisely the opposite characteristics. Through the results and analysis above, we find three ways to adjust the EPD and the OP via changing the chemical potential of the two-dimensional electron gas, the zero point of the pseudoharmonic potential, and the polaron radius.
Lee, J; Kachman, S D; Spangler, M L
2017-08-01
Genomic selection (GS) has become an integral part of genetic evaluation methodology and has been applied to all major livestock species, including beef and dairy cattle, pigs, and chickens. Significant contributions in increased accuracy of selection decisions have been clearly illustrated in dairy cattle after practical application of GS. In the majority of U.S. beef cattle breeds, similar efforts have also been made to increase the accuracy of genetic merit estimates through the inclusion of genomic information into routine genetic evaluations using a variety of methods. However, prediction accuracies can vary relative to panel density, the number of folds used for folds cross-validation, and the choice of dependent variables (e.g., EBV, deregressed EBV, adjusted phenotypes). The aim of this study was to evaluate the accuracy of genomic predictors for Red Angus beef cattle with different strategies used in training and evaluation. The reference population consisted of 9,776 Red Angus animals whose genotypes were imputed to 2 medium-density panels consisting of over 50,000 (50K) and approximately 80,000 (80K) SNP. Using the imputed panels, we determined the influence of marker density, exclusion (deregressed EPD adjusting for parental information [DEPD-PA]) or inclusion (deregressed EPD without adjusting for parental information [DEPD]) of parental information in the deregressed EPD used as the dependent variable, and the number of clusters used to partition training animals (3, 5, or 10). A BayesC model with π set to 0.99 was used to predict molecular breeding values (MBV) for 13 traits for which EPD existed. The prediction accuracies were measured as genetic correlations between MBV and weighted deregressed EPD. The average accuracies across all traits were 0.540 and 0.552 when using the 50K and 80K SNP panels, respectively, and 0.538, 0.541, and 0.561 when using 3, 5, and 10 folds, respectively, for cross-validation. Using DEPD-PA as the response variable resulted in higher accuracies of MBV than those obtained by DEPD for growth and carcass traits. When DEPD were used as the response variable, accuracies were greater for threshold traits and those that are sex limited, likely due to the fact that these traits suffer from a lack of information content and excluding animals in training with only parental information substantially decreases the training population size. It is recommended that the contribution of parental average to deregressed EPD should be removed in the construction of genomic prediction equations. The difference in terms of prediction accuracies between the 2 SNP panels or the number of folds compared herein was negligible.
Accuracy of Brief Screening Tools for Identifying Postpartum Depression Among Adolescent Mothers
Venkatesh, Kartik K.; Zlotnick, Caron; Triche, Elizabeth W.; Ware, Crystal
2014-01-01
OBJECTIVE: To evaluate the accuracy of the Edinburgh Postnatal Depression Scale (EPDS) and 3 subscales for identifying postpartum depression among primiparous adolescent mothers. METHODS: Mothers enrolled in a randomized controlled trial to prevent postpartum depression completed a psychiatric diagnostic interview and the 10-item EPDS at 6 weeks, 3 months, and 6 months postpartum. Three subscales of the EPDS were assessed as brief screening tools: 3-item anxiety subscale (EPDS-3), 7-item depressive symptoms subscale (EPDS-7), and 2-item subscale (EPDS-2) that resemble the Patient Health Questionnaire-2. Receiver operating characteristic curves and the areas under the curves for each tool were compared to assess accuracy. The sensitivities and specificities of each screening tool were calculated in comparison with diagnostic criteria for a major depressive disorder. Repeated-measures longitudinal analytical techniques were used. RESULTS: A total of 106 women contributed 289 postpartum visits; 18% of the women met criteria for incident postpartum depression by psychiatric diagnostic interview. When used as continuous measures, the full EPDS, EPDS-7, and EPDS-2 performed equally well (area under the curve >0.9). Optimal cutoff scores for a positive depression screen for the EPDS and EPDS-7 were lower (≥9 and ≥7, respectively) than currently recommended cutoff scores (≥10). At optimal cutoff scores, the EPDS and EPDS-7 both had sensitivities of 90% and specificities of >85%. CONCLUSIONS: The EPDS, EPDS-7, and EPDS-2 are highly accurate at identifying postpartum depression among adolescent mothers. In primary care pediatric settings, the EPDS and its shorter subscales have potential for use as effective depression screening tools. PMID:24344102
NASA Astrophysics Data System (ADS)
Fuji, Hiroshi; Kikukawa, Takashi; Tominaga, Junji
2004-07-01
Pit-edge recording at a density of 150 nm pits and spaces is carried out on a super-resolution near-field structure (super-RENS) disk with a platinum oxide layer. Pits are recorded and read using a 635-nm-wavelength laser and an objective lens with a 0.6 numerical aperture. We arrange laser pulses to correctly record the pits on the disk by a write-strategy technique. The laser-pulse figure includes a unit time of 0.25 T and intensities of Pw1, Pw2 and Pw3. After recording pits of various lengths, the observation of an eye pattern is achieved despite a pit smaller than the resolution limit. Furthermore, the eye pattern maintains its shape even though other pits fill the adjacent tracks at a track density of 600 nm. The disk can be used as a pit-edge recording system through a write-strategy technique.
Recent patents on electrophoretic displays and materials.
Christophersen, Marc; Phlips, Bernard F
2010-11-01
Electrophoretic displays (EPDs) have made their way into consumer products. EPDs enable displays that offer the look and form of a printed page, often called "electronic paper". We will review recent apparatus and method patents for EPD devices and their fabrication. A brief introduction into the basic display operation and history of EPDs is given, while pointing out the technological challenges and difficulties for inventors. Recently, the majority of scientific publications and patenting activity has been directed to micro-segmented EPDs. These devices exhibit high optical reflectance and contrast, wide viewing angle, and high image resolution. Micro-segmented EPDs can also be integrated with flexible transistors technologies into flexible displays. Typical particles size ranges from 200 nm to 2 micrometer. Currently one very active area of patenting is the development of full-color EPDs. We summarize the recent patenting activity for EPDs and provide comments on perceiving factors driving intellectual property protection for EPD technologies.
Growth of high quality germanium films on patterned silicon substrates and applications
NASA Astrophysics Data System (ADS)
Vanamu, Ganesh
The principal objective of this work is to determine optimal pattern structures for highest quality (defect free) heteroepitaxial growth. High quality films of Ge on Si are of significant importance and can be used in high electron mobility devices, photodetectors for optical communications (1.3mum or 1.55mum) and integrating III-V optoelectronic devices. However, a 4% lattice mismatch and ˜ 50% thermal expansion mismatch between Ge and Si create three major challenges in growing high quality Ge films on Si, (a) high surface roughness due to a pronounced <110> crosshatch pattern, (b) high dislocation densities in Ge films and (c) high density of microcracks and wafer bending. A common way of reducing lattice and thermal expansion mismatch is to form a "virtual substrate (VS)" by growing a graded composition followed by a uniform layer of the desired epitaxial film on a defect-free Si substrate. Virtual graded layers could not decrease the dislocation densities to the numbers acceptable for most of the devices. Mathews et al. first proposed that limiting the lateral dimensions of the sample prior to growth could reduce the dislocation density. Later On Fitzgerald proposed that patterning decreases the dislocation density in the films. In this work we show high quality crosshatch-free Ge films with dislocation density ˜ 105 cm-2 on the nano-patterned Si and also high quality GaAs films on the Ge/Si virtual substrate. The first step in this research was to perform a systematic study to identify the role of pattern width on the quality of Ge growth. We investigated micrometer and submicrometer scale patterns. We demonstrated that the quality of the heteroepitaxial layers improves as the pattern width decreases. Then we have decreased the pattern width to nanometer-scale dimensions. Significant improvement of the Ge film quality was observed. We used novel interferometric lithography techniques combined with reactive ion and wet chemical etching to fabricate Si structures. The patterning was done using standard photomask based lithography. We analyzed the quality of the Ge films using high resolution x-ray diffraction, TEM and SEM. We performed etch pit density (EPD) measurements by counting the pits formed using a Nomarski optical microscope. In order to correlate characterization with device performance, we designed an inter-digitated pattern to form Ge based metal semiconductor metal photodetector and measured the photoresponse of the Ge films. Preliminary results were very promising. We then grew 4 mum GaAs on the Ge/Si using MBE (0.5 mum/hr and 570°C) and analyzed the GaAs film quality. We also performed modeling to calculate strain energy density and wafer bending in multi-layer films grown epitaxially on planar Si substrates. We have also compared the models with experiments. (Abstract shortened by UMI.)
Evidence overview: benefit of cerebral protection devices during carotid artery stenting.
Vos, Jan A
2017-04-01
Embolic protection devices (EPDs) are often used during carotid angioplasty and stenting (CAS) to reduce procedural cerebral emboli. This manuscript seeks to present an overview of evidence on EPDs during CAS. There are three categories of EPDs: distal occlusion (DO-EPD), filter (F-EPD) and proximal occlusion (PO-EPD). DO and F-EPDs have the disadvantage that the device has to be advanced through the stenosis, without protection and that the device may damage the distal internal carotid artery (ICA). F-EPDs have the advantage of maintaining antegrade flow throughout the procedure. PO-EPDs occlude the ICA and external carotid artery (ECA) (blocking antegrade flow), but do not require manipulation of the stenosis before protection is established. All devices add to procedural time and costs. Many single-center series and meta-analyses have shown lower incidence of procedural complications and surrogate endpoints when EPDs are used. However, these series are hampered by a serious confounder: protected cases were generally performed later, when institutions had more experience and when newer stents, techniques etc. had become available. Two small randomized trials showed no difference between filter-protected and unprotected procedures in clinical outcome, but found significantly more surrogate endpoints (diffusion-weighted MRI lesions and transcranial Doppler detected micro-emboli) in the protected groups. Comparing between groups of EPDs, some studies slightly favored PO to F-EPDs, while others found no difference. All devices were associated with low numbers of clinical cerebral complications, but frequent surrogate signs of cerebral embolization. In conclusion, all currently available EPDs still result in some degree of cerebral embolization. No solid recommendation for a particular type of EPDs, if any, can be derived from literature.
Dependence of Crystallographic Orientation on Pitting Corrosion Behavior of Ni-Fe-Cr Alloy 028
NASA Astrophysics Data System (ADS)
Zhang, LiNa; Szpunar, Jerzy A.; Dong, JianXin; Ojo, Olanrewaju A.; Wang, Xu
2018-06-01
The influence of crystallographic orientation on the pitting corrosion behavior of Ni-Fe-Cr alloy 028 was studied using a combination of X-ray diffraction (XRD), electron backscatter diffraction (EBSD), potentiodynamic polarization technique, and atomic force microscopy (AFM). The results show that there is anisotropy of pitting corrosion that strongly depends on crystallographic orientation of the surface plane. The distribution of pit density in a standard stereographic triangle indicates that the crystallographic planes close to {100} are more prone to pitting corrosion compared to planes {110} and {111}. The surface energy calculation of (001) and (111) shows that the plane with a high atomic packing density has a low surface energy with concomitant strong resistance to pitting corrosion. A correlation function between crystallographic orientation and pitting corrosion susceptibility suggests a method that not only predicts the pitting resistance of known textured materials, but also could help to improve corrosion resistance by controlling material texture.
Single- and two-color infrared focal plane arrays made by MBE in HgCdTe
NASA Astrophysics Data System (ADS)
Zanatta, Jean-Paul; Ferret, P.; Loyer, R.; Petroz, G.; Cremer, S.; Chamonal, Jean-Paul; Bouchut, Philippe; Million, Alain; Destefanis, Gerard L.
2000-12-01
We present here recent developments obtained at LETI infrared laboratory in the field of infrared detectors made in HgCdTe material and using the molecular beam epitaxial growth technique (MBE). We discuss the metallurgical points (growth temperature and flux control) that lead to achieve excellent quality epitaxial layers grown by MBE. We show a run-to-run reproducibility measured on growth run of more than 15 layers. The crystalline quality, surface morphology, and composition uniformity are excellent. The etch pits density (EPD) are in the low 105.cm-2 when HgCdTe grows on a CdZnTe substrate. Transport properties reveal a low n-type carrier concentration in the 1014 to 1015.cm-3 range with a carrier mobility in excess of 105 cm2/V/sec at 77K for epilayers grown with 10 micrometers cutoff wavelength. We describe the performances of several kinds of our HgCdTe- MBE devices: single color MWIR and LWIR detectors on HgCdTe/CdZnTe operating at 77K in respectively (3-5 micrometers ) and (8-12 micrometers ) wavelength range; single color MWIR detectors on HgCdTe grown on germanium heterosubstrate operating at 77K in the (3-5 micrometers ) wavelength range; two color HgCdTe detectors operating within the MWIR (3-5 micrometers ) band.
Ochi, Y; Mukawa, K; Kiyosawa, K; Akamatsu, T
1999-01-01
To compare the clinical usefulness of endoscopic papillary dilation (EPD) and endoscopic sphincterotomy (EST) for removal of bile duct stones, 110 patients with stones up to 15 mm in diameter and less than 10 in number were randomly treated with either EPD (55 patients) or EST (55 patients). The patients were followed up for a median period of 23 months and endoscopic manometry with the administration of morphine was carried out in 17 patients who were observed more than 12 months after the procedures to evaluate the post-procedure papillary function. Duct clearance was achieved in 51 EPD (92.7%) and 54 EST patients (98.1%, not significantly different). Forty EPD (78.4%) and 51 EST patients (94.4%) achieved duct clearance in the initial procedure (P=0.02). Early complications occurred in one EPD (2.0%) and in three EST patients (5.6%, P=0.62). Complications during the follow-up period occurred in two EPD and eight EST patients. Recurrence of bile duct stones was observed in two EPD and three EST patients (P=0.98). Acute cholecystitis was observed in one EPD and five EST patients (P=0.06) and among patients with gall-bladder stones in situ, the rate of acute cholecystitis after EPD was significantly lower than that after EST (P=0.03). Endoscopic manometry showed the existence of a choledochoduodenal pressure gradient only after EPD, while papillary contractile function was observed after both procedures. In conclusion, both EPD and EST are safe therapeutic modalities, although EPD is more clinically effective in decreasing the risk of acute cholecystitis in patients with gall-bladder stones in situ and in preserving post-procedure papillary function.
van Haaften, Caroline; Boot, Arnoud; Corver, Willem E; van Eendenburg, Jaap D H; Trimbos, Baptist J M Z; van Wezel, Tom
2015-04-25
Ovarian cancer remains still the leading cause of death of gynecological malignancy, in spite of first-line chemotherapy with cisplatin and paclitaxel. Although initial response is favorably, relapses are common and prognosis for women with advanced disease stays poor. Therefore efficacious approaches are needed. Previously, an anti-cancer agent, EPD exhibited potent cytotoxic effects towards ovarian cancer and not towards normal cells. Cell viability and cell cycle analysis studies were performed with EPD, in combination with cisplatin and/or paclitaxel, using the ovarian carcinoma cell lines: SK-OV-3, OVCAR-3, JC, JC-pl and normal fibroblasts. Cell viability was measured using Presto Blue and cell cycle analysis using a flow cytometer. Apoptosis was measured in JC and JC-pl , using the caspase 3 assay kit. In JC-pl, SK-OV-3 and JC, synergistic interactions between either EPD and cisplatin or EPD and paclitaxel were observed. For the first time the effects of EPD on the cell cycle of ovarian cancer cells and normal cells was studied. EPD and combinations of EPD with cisplatin and/ or paclitaxel showed cell cycle arrest in the G2/M phase. The combination of EPD and cisplatin showed a significant synergistic effect in cell line JC-pl, while EPD with paclitaxel showed synergistic interaction in JC. Additionally, synergistic drug combinations showed increased apoptosis. Our results showed a synergistic effect of EPD and cisplatin in an ovarian drug resistant cell line as well as a synergistic effect of EPD and paclitaxel in two other ovarian cell lines. These results might enhance clinical efficacy, compared to the existing regimen of paclitaxel and cisplatin.
NASA Astrophysics Data System (ADS)
Li, Hui-yan; Dong, Chao-fang; Xiao, Kui; Li, Xiao-gang; Zhong, Ping
2016-11-01
The effects of Cl- ion concentration and pH values on the corrosion behavior of Cr12Ni3Co12Mo4W ultra-high-strength martensitic stainless steel (UHSMSS) were investigated by a series of electrochemical tests combined with observations by stereology microscopy and scanning electron microscopy. A critical Cl- ion concentration was found to exist (approximately 0.1wt%), above which pitting occurred. The pitting potential decreased with increasing Cl- ion concentration. A UHSMSS specimen tempered at 600°C exhibited a better pitting corrosion resistance than the one tempered at 400°C. The corrosion current density and passive current density of the UHSMSS tempered at 600°C decreased with increasing pH values of the corrosion solution. The pits developed a shallower dish geometry with increasing polarization potential. A lacy cover on the pits of the UHSMSS tempered at 400°C accelerated pitting, whereas corrosion products deposited in the pits of the UHSMSS tempered at 600°C hindered pitting.
Mathew, Dennis; Bhardwaj, Garima; Wang, Qi; Sun, Linlin; Ercan, Batur; Geetha, Manisavagam; Webster, Thomas J
2014-01-01
Plasma-spray deposition of hydroxyapatite on titanium (Ti) has proven to be a suboptimal solution to improve orthopedic-implant success rates, as demonstrated by the increasing number of orthopedic revision surgeries due to infection, implant loosening, and a myriad of other reasons. This could be in part due to the high heat involved during plasma-spray deposition, which significantly increases hydroxyapatite crystal growth into the nonbiologically inspired micron regime. There has been a push to create nanotopographies on implant surfaces to mimic the physiological nanostructure of native bone and, thus, improve osteoblast (bone-forming cell) functions and inhibit bacteria functions. Among the several techniques that have been adopted to develop nanocoatings, electrophoretic deposition (EPD) is an attractive, versatile, and effective material-processing technique. The in vitro study reported here aimed to determine for the first time bacteria responses to hydroxyapatite coated on Ti via EPD. There were six and three times more osteoblasts on the electrophoretic-deposited hydroxyapatite on Ti compared with Ti (control) and plasma-spray-deposited hydroxyapatite on Ti after 5 days of culture, respectively. Impressively, there were 2.9 and 31.7 times less Staphylococcus aureus on electrophoretic-deposited hydroxyapatite on Ti compared with Ti (control) and plasma-spray-deposited hydroxyapatite on Ti after 18 hours of culture, respectively. Compared with uncoated Ti and plasma-sprayed hydroxyapatite coated on Ti, the results provided significant promise for the use of EPD to improve bone-cell density and be used as an antibacterial coating without resorting to the use of antibiotics.
Symptoms of maternal depression immediately after delivery predict unsuccessful breast feeding.
Gagliardi, Luigi; Petrozzi, Angela; Rusconi, Franca
2012-04-01
Postnatal depression may interfere with breast feeding. This study tested the ability of the Edinburgh Postnatal Depression Scale (EPDS) to predict later breast feeding problems, hypothesising that risk of unsuccessful breast feeding increased with increasing EPDS scores, even at low values. The authors administered the EPDS on days 2-3 after delivery to 592 mothers of a healthy baby. Feeding method was recorded at 12-14 weeks. Median EPDS score was 5 (IQR 2 -8); 15.7% of women scored >9. At 12-14 weeks, 50.7% of infants received full breast feeding, 21.0% mixed breast feeding and 28.4% bottle feeding. Mothers with higher EPDS scores were more likely to bottle feed at 3 months; the odds of bottle feeding increased with EPDS result, even at low scores (OR 1.06, 95% CI 1.01 to 1.11). Higher EPDS scores immediately after delivery were associated with later breast feeding failure.
Yi, Jianyong; Zhou, Linyan; Bi, Jinfeng; Chen, Qinqin; Liu, Xuan; Wu, Xinye
2016-02-01
The effects of hot air drying (AD), freeze drying (FD), infrared drying (IR), microwave drying (MV), vacuum drying (VD) as pre-drying treatments for explosion puff drying (EPD) on qualities of jackfruit chips were studied. The lowest total color differences (∆E) were found in the FD-, MV- and VD-EPD dried chips. Volume expansion effect (9.2 %) was only observed in the FD-EPD dried chips, which corresponded to its well expanded honeycomb microstructures and high rehydration rate. Compared with AD-, IR-, MV- and VD-EPD, the FD-EPD dried fruit chips exhibited lower hardness and higher crispness, indicative of a crispier texture. FD-EPD dried fruits also obtained high retentions of ascorbic acid, phenolics and carotenoids compared with that of the other puffed products. The results of sensory evaluation suggested that the FD-EPD was a more beneficial combination because it enhanced the overall qualities of jackfruit chips. In conclusion, the FD-EPD could be used as a novel combination drying method for processing valuable and/or high quality fruit chips.
Adolfsson, Päivi; Lindstedt, Helena; Pettersson, Ingvor; Hermansson, Liselotte Norling; Janeslätt, Gunnel
2016-08-01
Adults with cognitive disabilities often have difficulties in dealing with the complexity of everyday life. With cognitive assistive technology (e.g. electronic planning devices [EPDs] and individual support), they can bring order to their often chaotic life. Assumptions are that environmental factors influence with non-use of EPDs. To explore how adults with cognitive disabilities perceive the influence of environmental factors in the use of EPDs. A reference group with experience of use of EPDs assisted the researchers. Twelve adults with cognitive disabilities and experience of using EPDs participated. An interview guide was implemented covering environmental factors according to the International Classification of Functioning, Disability and Health. Qualitative content analysis was applied in the analyses. Five categories and two themes emerged, which were integrated into a model of facilitating factors influencing the use of EPDs. Measures to prevent or eliminate negative influences of the device use are important to be taken. Professionals need more knowledge about EPDs, while users need individual adaption of the EPDs. EPDs need to be user-friendly, manageable and work in any seasons. Implications for Rehabilitation The users should have access to specially trained prescribers. There is a need for development of user-friendly and manageable products to function in any climate. Knowledge is lacking on how to implement the users in all stages of the prescribing process. Prescribers should increase knowledge in the use of EPDs to influence the attitudes of the social environment.
Enhancement of Device Performances in GaN-Based Light-Emitting Diodes Using Nano-Sized Surface Pit.
Yeon, Seunghwan; Son, Taejoon; Shin, Dong Su; Jung, Kyung-Young; Park, Jinsub
2015-07-01
We report the improvement in optical and electrical properties of GaN-based green light-emitting diodes (LEDs) with nano-sized etch pits formed by the surface chemical etching. In order to control the density and sizes of etch pits formed on top surface of green LEDs, H3PO4 solution is used as a etchant with different etching time. When the etching time was increased from 0 min to 20 min, both the etch pit size and density were gradually increased. The improvement of extraction efficiency of LEDs using surface etching method can be attributed to the enlarged escape angle of generated photon by roughened p-GaN surface. The finite-difference time-domain (FDTD) simulation results well agreed with experimentally observed results. Moreover, the LED with etched p-GaN surface for 5 min shows the lowest leakage current value and the further increase of etching time resulting in increase of densities of the large-sized etch pit makes the degradation of electrical properties of LEDs.
Assessing the spatial relationship between fixation and foveal specializations.
Wilk, Melissa A; Dubis, Adam M; Cooper, Robert F; Summerfelt, Phyllis; Dubra, Alfredo; Carroll, Joseph
2017-03-01
Increased cone photoreceptor density, an avascular zone (FAZ), and the displacement of inner retinal neurons to form a pit are distinct features of the human fovea. As the fovea provides the majority of our vision, appreciating how these anatomical specializations are related is important for understanding foveal development, normal visual function, and retinal disease. Here we evaluated the relationship between these specializations and their location relative to the preferred retinal locus of fixation (PRL). We measured foveal pit volume, FAZ area, peak cone density, and location of the PRL in 22 subjects with normal vision using optical coherence tomography and adaptive optics scanning light ophthalmoscopy. Foveal pit volume was positively correlated with FAZ area; however, peak cone density was not correlated with pit volume. In addition, there was no systematic offset of the location of any of these specializations relative to PRL, and there was no correlation between the magnitude of the offset from PRL and the corresponding foveal specialization measurements (pit volume, FAZ area, peak cone density). The standard deviation of our PRL measurements was consistent with previous measurements of fixational stability. These data provide insight into the sequence of events during foveal development and may have implications for visual function and retinal disease. Copyright © 2016 Elsevier Ltd. All rights reserved.
The Swedish validation of Edinburgh Postnatal Depression Scale (EPDS) during pregnancy.
Rubertsson, Christine; Börjesson, Karin; Berglund, Anna; Josefsson, Ann; Sydsjö, Gunilla
2011-12-01
Around 10-15% of women suffer from depressive illness during pregnancy or the first year postpartum. Depression during pregnancy constitutes a risk for prenatal stress and preterm birth. No validated screening instrument for detecting depression during pregnancy was available in Swedish. We aimed to validate the Edinburgh Postnatal Depression Scale (EPDS) against DSM-IV criteria for depression during pregnancy, establish a reliable cut-off and estimate the correlation between the EPDS and HAD-S (Hospital Anxiety and Depression Scale). In a population-based community sample of 1175 pregnant women, 918 women (78%) answered questionnaires with the EPDS and HAD-S. In all, 121 were interviewed using the PRIME-MD (Primary Care Evaluation of Mental disorders) for diagnosing depression. Women were interviewed in mean gestational week 13 (range 8-21). For the EPDS, a receiver operating characteristic (ROC) curve was calculated for prediction of depression. Pearson's correlation coefficient was used to investigate the association between EPDS and HAD-S scores. The optimal cut-off score on the EPDS scale for detecting depression was ≥13 (standard error coefficient of 1.09 and c-statistics of 0.84) giving a sensitivity of 77% and specificity of 94%. The EPDS scores correlated strongly with the HAD-S, Pearson's correlation was 0.83 (P < 0.0001). This study confirms that the EPDS is a valid screening instrument for detection of depressive symptoms during pregnancy. The EPDS shows persuasive measuring outcomes with an optimal cut-off at ≥13. Healthcare for pregnant women should consider screening procedures and follow-up routines for depressive symptoms.
Validation of the Edinburgh Postnatal Depression Scale (EPDS) on the Thai–Myanmar border
Ing, Harriet; Fellmeth, Gracia; White, Jitrachote; Stein, Alan; Simpson, Julie A; McGready, Rose
2017-01-01
Postnatal depression is common and may have severe consequences for women and their children. Locally validated screening tools are required to identify at-risk women in marginalised populations. The Edinburgh Postnatal Depression Scale (EPDS) is one of the most frequently used tools globally. This cross-sectional study assessed the validity and acceptability of the EPDS in Karen and Burmese among postpartum migrant and refugee women on the Thai–Myanmar border. The EPDS was administered to participants and results compared with a diagnostic interview. Local staff provided feedback on the acceptability of the EPDS through a focus group discussion. Results from 670 women showed high accuracy and reasonable internal consistency of the EPDS. However, acceptability to local staff was low, limiting the utility of the EPDS in this setting despite its good psychometrics. Further work is required to identify a tool that is acceptable and sensitive to cultural manifestations of depression in this vulnerable population. PMID:28699396
High quality InP-on-Si for solar cell applications
NASA Technical Reports Server (NTRS)
Shellenbarger, Zane A.; Goodwin, Thomas A.; Collins, Sandra R.; Dinetta, Louis C.
1994-01-01
InP on Si solar cells combine the low-cost and high-strength of Si with the high efficiency and radiation tolerance of InP. The main obstacle in the growth of single crystal InP-on-Si is the high residual strain and high dislocation density of the heteroepitaxial InP films. The dislocations result from the large differences in lattice constant and thermal expansion mismatch of InP and Si. Adjusting the size and geometry of the growth area is one possible method of addressing this problem. In this work, we conducted a material quality study of liquid phase epitaxy overgrowth layers on selective area InP grown by a proprietary vapor phase epitaxy technique on Si. The relationship between growth area and dislocation density was quantified using etch pit density measurements. Material quality of the InP on Si improved both with reduced growth area and increased aspect ratio (length/width) of the selective area. Areas with etch pit density as low as 1.6 x 10(exp 4) sq cm were obtained. Assuming dislocation density is an order of magnitude greater than etch pit density, solar cells made with this material could achieve the maximum theoretical efficiency of 23% at AMO. Etch pit density dependence on the orientation of the selective areas on the substrate was also studied.
El-Hachem, Charline; Rohayem, Jihane; Bou Khalil, Rami; Richa, Sami; Kesrouani, Assaad; Gemayel, Rima; Aouad, Norma; Hatab, Najat; Zaccak, Eliane; Yaghi, Nancy; Salameh, Salimé; Attieh, Elie
2014-09-07
During the postpartum period, women are vulnerable to depression affecting about 10 to 20% of mothers during the first year after delivery. However, only 50% of women with prominent symptoms are diagnosed with postpartum depression (PPD). The Edinburgh Postnatal Depression Scale (EPDS) is the most widely used screening instrument for PPD . The main objectives of this study are to assess whether an EPDS score of 9 or more on day 2 (D2) postpartum is predictive of a depressive episode between days 30 and 40 postpartum (D30-40), to determine the risk factors as well as the prevalence of PPD in a sample of Lebanese women and to determine a threshold score of EPDS predictive of PPD. A sample of 228 women were administered the EPDS on D2. An assessment for PPD was done on D30-40 during a telephone interview. On D2, the average score on EPDS was 7.1 (SD = 5.2) and 33.3% of women had an EPDS score ≥ 9. On D30-40 postpartum, the average score was 6.5 (SD = 4.7) and 19 women (12.8%) presented with PPD. A positive correlation was shown between scores on EPDS on D2 and D30-40 (r = 0.5091, p < 0.0001). A stepwise regression shows that an EPDS score ≥9 on D2 (p < 0.001) and a personal history of depression (p = 0.008) are significantly associated with the diagnosis of PPD on D30-40. The EPDS may be considered as a reliable screening tool on as early as D2 after delivery. Women with EPDS score ≥ 9 and/or a positive personal history of major depressive disorder should benefit from a closer follow-up during the rest of the post-partum period.
Ramachandran Pillai, Raji; Wilson, Anand Babu; Premkumar, Nancy R.; Kattimani, Shivanand; Sagili, Haritha
2018-01-01
Postpartum depression (PPD) is a psychiatric complication of childbirth affecting 10–20% of new mothers and has negative impact on both mother and infant. Serum lipid levels have been related to depressive disorders, but very limited literatures are available regarding the lipid levels in women with postpartum depression. The present study is aimed to examine the association of serum lipids with the development of postpartum depressive symptoms. This is a cross sectional study conducted at a tertiary care hospital in South India. Women who came for postpartum check-up at 6th week post-delivery were screened for PPD (September 2014-October 2015). Women with depressive symptoms were assessed using EPDS (Edinburgh Postnatal Depression Scale). The study involved 186 cases and 250 controls matched for age and BMI. Serum levels of lipid parameters were estimated through spectrophotometry and the atherogenic indices were calculated in all the subjects. Low serum levels of Total Cholesterol (TC) and High Density Lipoprotein cholesterol (HDL-c) were significantly low in PPD women with severe depressive symptoms. The study recorded a significant negative correlation between HDL-c and the EPDS score in PPD women (r = -0.140, p = 0.05). Interestingly, the study also observed a significant negative correlation between Body Mass Index (BMI) and EPDS scores in case group (r = -0.146, p = 0.047), whereas a positive correlation between the same in controls (r = 0.187, p = 0.004). Our study demonstrated that low levels of serum HDL-c is correlated with the development of severe depressive symptoms in postpartum women. Study highlights the role of lipids in the development of postpartum depressive symptoms. PMID:29444162
Wang, Mei; Duong, Le Dai; Mai, Nguyen Thi; Kim, Sanghoon; Kim, Youngjun; Seo, Heewon; Kim, Ye Chan; Jang, Woojin; Lee, Youngkwan; Suhr, Jonghwan; Nam, Jae-Do
2015-01-21
Portable energy storage devices have gained special attention due to the growing demand for portable electronics. Herein, an all-solid-state supercapacitor is successfully fabricated based on a poly(vinyl alcohol)-H3PO4 (PVA-H3PO4) polymer electrolyte and a reduced graphene oxide (RGO) membrane electrode prepared by electrophoretic deposition (EPD). The RGO electrode fabricated by EPD contains an in-plane layer-by-layer alignment and a moderate porosity that accommodate the electrolyte ions. The all-solid-state RGO supercapacitor is thoroughly tested to give high specific volumetric capacitance (108 F cm(-3)) and excellent energy and power densities (7.5 Wh cm(-3) and 2.9 W cm(-3), respectively). In addition, the all-solid-state RGO supercapacitor exhibits an ultralong lifetime for as long as 180 days (335 000 cycles), which is an ultrahigh cycling capability for a solid-state supercapacitor. The RGO is also tested for being used as a transparent supercapacitor electrode demonstrating its possible use in various transparent optoelectronic devices. Due to the facile scale-up capability of the EPD process and RGO dispersion, the developed all-solid-state supercapacitor is highly applicable to large-area portable energy storage devices.
Xu, Ming-Ming; Guo, Jing-Ke; Xu, Jin-Sen; Zhang, Chao-Xin; Liu, Shu-Tao; Liao, Ri-Tao; Lin, Chun-Tong; Guo, Jian-Hui; Rao, Ping-Fan
2015-01-01
Previous studies suggest that superoxide anions are possibly traveling along acupuncture meridians. The electrical potential difference (EPD) between acupoints may be related to the movement. To test the above hypothesis, we conducted a study investigating the effects of acupoint antioxidant interventions on the meridian EPD. Firstly, ST39 (L) and ST44 (L) were screened out for the EPD detection along the stomach meridian, and ST36 (L) was selected for interventions including acumassage with the control cream, as well as the TAT-SOD cream for 30 minutes, or injection with reduced glutathione sodium. The EPD between ST39 and ST44 was recorded for 80 minutes and measured again 48 h later. While the EPD increased during the acumassage, the acumassage with TAT-SOD cream and the glutathione injection generated waves of EPD increased, indicating the migration or removal from the visceral organ of a greater quantity of superoxide. Remarkably lower EPD readings 48 h later with both antioxidant acupoint interventions than the mere acumassage imply a more complete superoxide flushing out due to the restored superoxide pathway at the acupoint after interventions. The results confirm superoxide transportation along the meridians and demonstrate a possibility of acupoint EPD measurement as a tool to monitor changes in the meridians and acupoints.
Enzyme-potentiated desensitization in children with asthma and mite allergy: a double-blind study.
Cantani, A; Ragno, V; Monteleone, M A; Lucenti, P; Businco, L
1996-01-01
The aim of this study was to evaluate the efficacy and safety of enzyme-potentiated desensitization (EPD) in children with asthma. Twenty asthmatic children (14 males and 6 females; median age: 8.5 years) were included in the study. They had positive skin tests to Dermatophagoides pteronyssinus (Dpt), no history of other allergy and had suffered from asthma for at least two years. The children were examined before starting the trial, at the first EPD dose, after 8 weeks, at the second EPD dose and 3 months after the second EPD dose. Blood samples for PRIST and RAST were drawn before the first and at the second EPD dose, and at the last follow-up. Conjunctival provocation tests (CPT) and skin test endpoint determinations were performed with dilutions of a freeze-dried Dpt extract (10-100,000 SQ-U/ml) at the start of the trial and at the last follow-up. Parents kept a diary record of the days with asthma and daily drug usage. The children were randomized to receive either two intradermal placebo injections or the active material with an 8-week interval (November 1991 and January 1992). Ten children received EPD and 10 children placebo. The intradermal injection of EPD (0.05 ml) contained 0.01 ml of beta-glucuronidase (40 Fishman units) and 0.04 ml of a mixture of inhalant allergens (1 Noon unit). The placebo injection consisted of buffer solution only. The EPD-treated children had significantly fewer days with asthma (p = 0.00000). In addition, the EPD-treated children used significantly less medication for the management of asthma attacks (p = 0.00000). At the start of the trial, three out of 10 children in the EPD group and two out of 10 in the placebo group reacted only to the highest dose of allergen used in the CPT (100,000 SQ/ml) (NS). At the last follow-up, the threshold dose in the CPT was 100,000 SQ/ml or more in nine out of 10 children in the EPD group and in four out of 10 children of the placebo group (p = 0.0349). At the last follow-up, one child in the EPD group had a negative CPT with all doses tested. Global clinical evaluation by the investigators showed that eight out of 10 EPD-treated children improved, in comparison with three out of 10 children in the placebo group (p = 0.0349). Assessment by the parents was six out of 10 and four out of 10 improved, respectively (NS). Specific IgE to Dpt, total IgE and skin prick test endpoints before and after EPD showed no significant changes. One child in the placebo group experienced mild urticaria several hours following the second injection. No other local or systemic side effects were reported. The results of the present study provide further data on the effectiveness and safety of EPD in patients with asthma.
Note on the thermally induced changes of intervessel pits in black cherry (Prunus serotina EHRH)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elder, T.J.; Murphey, W.K.; Blankenhorn, P.R.
1979-01-01
Dimensions of intervessel pits decrease as charring temperatures increase to 600 C; above 600 C pit apertures remain relatively constant. Reported increases in density of chars above 600 C are attributed to coalescing of the cell wall or changes in intercellular interstices shrinkage. 1 figure, 1 table.
Paul, Timir K; Lee, John H; White, Christopher J
2012-11-15
We sought to measure angiographic renal frame counts (RFC), as a quantitative angiographic assessment of renal blood flow, to evaluate microvascular compromise due to atheroembolism associated with RAS. Atheroembolism associated with renal artery stenting (RAS) has been implicated as a cause for worsening renal function following successful intervention. Use of a distal embolic protection device (EPD) during RAS has been shown to be safe with debris capture in a high percentage of cases. However, objective benefit for renal function with EPD has been difficult to demonstrate. A control group of 30 consecutive patients (33 kidneys) who underwent RAS without EPD were compared with 33 consecutive patients (33 kidneys) who underwent RAS with EPD using RFC measurement. The prestent and poststent mean RFC for the control group was 30.4 ± 12.1 vs. 23.7 ± 9.9 (P = 0.002) and for the EPD group it was 42.6 ± 12.6 vs. 28.3 ± 9.2 (P < 0.0001). The EPD group had a greater improvement in renal blood flow, manifested by a greater reduction of the RFC (Δ RFC) 14.2 ± 15.2 vs. 6.7 ± 11.7 (P = 0.03) compared with the control group. The use of an EPD was associated with a much larger improvement in renal blood flow (lower RFC) following RAS. This suggests that EPD's may be effective in preventing renal atheroembolic injury and that a controlled trial measuring the impact of EPD's on renal blood flow following RAS should be performed. Copyright © 2012 Wiley Periodicals, Inc.
Massoudi, Pamela; Hwang, C Philip; Wickberg, Birgitta
2013-07-01
Fathers are increasingly involved in infant care, and depression in postnatal fathers as well as mothers may have negative effects on child development and behaviour. The EPDS has been validated to identify depression in new mothers, but few validation studies have involved fathers and there is doubt as to whether the EPDS measures the same constructs in men as in women. A population-based sample of 1014 couples were sent the EPDS and the HAD-A subscale 3 months postnatally. All high-scoring fathers and a random sample of fathers scoring low were invited for a diagnostic interview to assess the presence of any depression or anxiety disorder. A factor analysis of the EPDS data was conducted for mothers and fathers. A factor analysis of the EPDS data revealed a different factor structure for fathers, implying that the scale picks up more worry, anxiety and unhappiness than depression. The EPDS yields high sensitivity and specificity, but low positive predictive value when screening for probable major depression at the optimal cut-off score of 12 or more. The accuracy of the EPDS, however, is modest for minor depression, and low for anxiety disorders. Neither the EPDS-3A score nor the HAD-A subscale reached acceptable validity in this study. The EPDS seems to pick up more distress than pure depression in new fathers. It is a valid instrument for screening for probable major depression, but it is questionable if it should be used to screen for minor depression. Neither the EPDS nor the HAD-A subscale can be recommended for screening for anxiety in postnatal fathers. Confidence intervals around the estimates are wide and the interviewed fathers were selected preferentially. Copyright © 2013 Elsevier B.V. All rights reserved.
Kubota, Chika; Okada, Takashi; Aleksic, Branko; Nakamura, Yukako; Kunimoto, Shohko; Morikawa, Mako; Shiino, Tomoko; Tamaji, Ai; Ohoka, Harue; Banno, Naomi; Morita, Tokiko; Murase, Satomi; Goto, Setsuko; Kanai, Atsuko; Masuda, Tomoko; Ando, Masahiko; Ozaki, Norio
2014-01-01
The Edinburgh Postnatal Depression Scale (EPDS) is a widely used screening tool for postpartum depression (PPD). Although the reliability and validity of EPDS in Japanese has been confirmed and the prevalence of PPD is found to be about the same as Western countries, the factor structure of the Japanese version of EPDS has not been elucidated yet. 690 Japanese mothers completed all items of the EPDS at 1 month postpartum. We divided them randomly into two sample sets. The first sample set (n = 345) was used for exploratory factor analysis, and the second sample set was used (n = 345) for confirmatory factor analysis. The result of exploratory factor analysis indicated a three-factor model consisting of anxiety, depression and anhedonia. The results of confirmatory factor analysis suggested that the anxiety and anhedonia factors existed for EPDS in a sample of Japanese women at 1 month postpartum. The depression factor varies by the models of acceptable fit. We examined EPDS scores. As a result, "anxiety" and "anhedonia" exist for EPDS among postpartum women in Japan as already reported in Western countries. Cross-cultural research is needed for future research.
ASSOCIATION BETWEEN NON-ENZYMATIC GLYCATION, RESORPTION, AND MICRODAMAGE IN HUMAN TIBIAL CORTICES
Karim, Lamya; Diab, Tamim; Vashishth, Deepak
2015-01-01
Purpose/Introduction Changes in the quality of bone material contribute significantly to bone fragility. In order to establish a better understanding of the interaction of the different components of bone quality and their influence on bone fragility we investigated the relationship between non-enzymatic glycation, resorption, and microdamage generated in vivo in cortical bone using bone specimens from the same donors. Methods Total fluorescent advanced glycation end-products (AGEs) were measured in 96 human cortical bone samples from 83 donors. Resorption pit density, average resorption pit area, and percent resorption area were quantified in samples from 48 common donors with AGE measurements. Linear microcrack density and diffuse damage were measured in 21 common donors with AGE and resorption measurements. Correlation analyses were performed between all measured variables to establish the relationships among them and their variation with age. Results We found that average resorption pit area and percent resorption area decreased with increasing AGEs independently of age. Resorption pit density and percent resorption area demonstrated negative age-adjusted correlation with diffuse damage. Furthermore, average resorption pit area, resorption pit density, and percent resorption area were found to decrease significantly with age. Conclusions The current study demonstrated the in vivo interrelationship between the organic constituents, remodeling, and damage formation in cortical bone. In addition to the age-related reduction in resorption, there is a negative correlation between AGEs and resorption independent of age. This inverse relationship indicates that AGEs alter the resorption process and/or accumulate in the tissue as a result of reduced resorption and may lead to bone fragility by adversely affecting fracture resistance through altered bone matrix properties. PMID:25326375
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Chi-Kang; Wu, Chen-Kuo; Hsu, Chung-Cheng
2016-05-15
In this paper, influence of a V-pit embedded inside the multiple quantum wells (MQWs) LED was studied. A fully three-dimensional stress-strain solver and Poisson-drift-diffusion solver are employed to study the current path, where the quantum efficiency and turn-on voltage will be discussed. Our results show that the hole current is not only from top into lateral quantum wells (QWs) but flowing through shallow sidewall QWs and then injecting into the deeper lateral QWs in V-pit structures, where the V-pit geometry provides more percolation length for holes to make the distribution uniform along lateral MQWs. The IQE behavior with different V-pitmore » sizes, threading dislocation densities, and current densities were analyzed. Substantially, the variation of the quantum efficiency for different V-pit sizes is due to the trap-assisted nonradiative recombination, effective QW ratio, and ability of hole injections.« less
NASA Technical Reports Server (NTRS)
French, R. A.; Cohen, B. A.; Miller, J. S.
2014-01-01
The Potassium-Argon Laser Experiment( KArLE), is composed of two main instruments: a spectrometer as part of the Laser-Induced Breakdown Spectroscopy (LIBS) method and a Mass Spectrometer (MS). The LIBS laser ablates a sample and creates a plasma cloud, generating a pit in the sample. The LIBS plasma is measured for K abundance in weight percent and the released gas is measured using the MS, which calculates Ar abundance in mols. To relate the K and Ar measurements, total mass of the ablated sample is needed but can be difficult to directly measure. Instead, density and volume are used to calculate mass, where density is calculated based on the elemental composition of the rock (from the emission spectrum) and volume is determined by pit morphology. This study aims to reduce the uncertainty for KArLE by analyzing pit volume relationships in several analog materials and comparing methods of pit volume measurements and their associated uncertainties.
Lau, Ying; Wong, Daniel Fu Keung; Chan, Kin Sin
2010-04-01
This paper aims to study the pattern of perinatal depressive symptomatology and determine the predictive power of second trimester perinatal depressive symptoms for future perinatal periods. A population-based sample of 2,178 women completed the Edinburgh Postnatal Depression Scale (EPDS) in the second and third trimesters and at 6 weeks postpartum. Repeated measures ANOVAs were used to determine the EPDS scores across three stages. The predictive power of the second trimester EPDS score in identifying women with an elevated EPDS score in the third trimester and at 6 weeks postpartum were determined. The predictive power of the second trimester EPDS score was further assessed using stepwise logistic regression and receiver operator characteristic curves. EPDS scores differed significantly across three stages. The rates were 9.9%, 7.8%, and 8.7% for an EPDS score of >14 in the second and third trimesters and at 6 weeks postpartum, respectively. Using a cut-off of 14/15, the second trimester EPDS score accurately classified 89.6% of women in the third trimester and 87.2% of those at 6 weeks postpartum with or without perinatal depressive symptomatology. Women with a second trimester EPDS score >14 were 11.78 times more likely in the third trimester and 7.15 times more likely at 6 weeks postpartum to exhibit perinatal depressive symptomatology after adjustment of sociodemographic variables. The area under the curve for perinatal depressive symptomatology was 0.85 in the third trimester and 0.77 at 6 weeks postpartum. To identify women at high risk for postpartum depression, healthcare professionals could consider screening all pregnant women in the second trimester so that secondary preventive intervention may be implemented.
Janeslätt, Gunnel; Lindstedt, Helena; Adolfsson, Päivi
2015-01-01
To describe daily time management in adults with and without mental disability and to examine differences in the level of their daily time management; to describe the possessions and use of electronic planning devices (EPDs) in activities and how environmental factors influence the use of EPDs in adults with mental disability. In a descriptive and cross-sectional design, 32 participants using EPDs and a matched comparison group of 32 healthy adults was recruited. Time-Self rating scale measuring daily time management was adapted for adults. A study specific questionnaire was applied to collect data on five ICF environmental factors. Rasch modelling, descriptive and non-parametric statistics were applied. Time-S has acceptable psychometric properties for use on adults with mental disability. People with mental disability and low level of daily time management who use advanced EPDs are more influenced by environmental factors. The study group perceived that encouragement and support from professionals as well as services influence their use of EPDs. Time-S can safely be used for people with mental disability. EPDs do not fully compensate the needs of the target-group. Prescribers need to give considerations to this and therefore they should be provided with more knowledge about this matter. Implications for Rehabilitation The Time-S can be applied for measuring daily time management in adults. Adults with mental disability provided with EPDs are not fully compensated in daily time management. Professional support and encouragement as well as backing from the services are important factors for the use of EPDs. Because the smart phones are not prescribed as assistive technology, the need for help from professionals to facilitate daily life is stressed. Therefore, the professionals should be provided with more knowledge about the use of EPDs.
Venkatesh, Kartik K; Kaimal, Anjali J; Castro, Victor M; Perlis, Roy H
2017-05-01
Universal screening of pregnant women for postpartum depression has recently been recommended; however, optimal application of depression screening tools in stratifying risk has not been defined. The current study examines new approaches to improve the ability of the Edinburgh Postnatal Depression Scale (EPDS) to stratify risk for postpartum depression, including alternate cut points, use of a continuous measure, and incorporation of other putative risk factors. An observational cohort study of 4939 women screened both antepartum and postpartum with a negative EPDS screen antepartum(i.e. EPDS<10). The primary outcome was a probable postpartum major depressive episode(EPDS cut-off ≥10). Area under the receiver operating characteristics curve(AUC), sensitivity, specificity, and predictive values were calculated. 287 women(5.8%) screened positive for postpartum depression. An antepartum EPDS cut-off<5 optimally identified women with a low risk of postpartum depression with a negative predictive value of 97.6%; however, overall discrimination was modest(AUC 0.66, 95%CI: 0.64-0.69); sensitivity was 78.7%, and specificity was 53.8%, and the positive predictive value was low at 9.5%. The negative predictive values were similar(>95%) at all antepartum EPDS cut-off values from 4 to 8. Discrimination was improved(AUC ranging from 0.70 to 0.73) when the antepartum EPDS was combined with a prior history of major depressive disorder before pregnancy. An inability to assess EPDS subscales and a relatively low prevalence of depression in this cohort. Though an antepartum EPDS cut-off score <5 yielded the greatest discrimination identifying women at low risk for postpartum depression, the negative predictive value was insufficient to substitute for postpartum screening. Copyright © 2017. Published by Elsevier B.V.
Omran, Jad; Mahmud, Ehtisham; White, Christopher J; Aronow, Herbert D; Drachman, Douglas E; Gray, William; Abdullah, Obai; Abu-Fadel, Mazen; Firwana, Belal; Mishkel, Gergory; Al-Dadah, Ashraf S
2017-04-01
Carotid artery stenting (CAS) is typically performed using embolic protection devices (EPDs) as a means to reduce the risk of procedure-related stroke. In this study, we compared procedural morbidity and mortality associated with distal (D-EPD) vs. proximal (P-EPD) protection. MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were queried from January 1998 through May 2015. Only studies comparing (D-EPD) and (P-EPD) were included. Two independent reviewers selected and appraised studies and extracted data in duplicate. Random-effects meta-analysis was used to pool outcomes across studies. Heterogeneity of treatment effect among studies was assessed using the I 2 statistics. Publication bias was assessed using inspection of funnel plots. The primary endpoints included 30-day mortality and stroke. Secondary endpoints included new cerebral lesions on diffusion-weighted magnetic resonance imaging (DW-MRI) and contralateral lesions on DW-MRI. A total of 12,281 patients were included from 18 studies (13 prospective and 5 retrospective) comparing (D-EPD) and (P-EPD) in the setting of CAS. The mean patient age was 69 years and 64% of patients were male. No evidence of publication bias was detected. There was no significant difference between the two modalities in terms of the risk of stroke (risk difference [RD] 0.0, 95% confidence interval [CI] -0.01 to 0.01) or mortality (RD 0.0, 95% CI -0.01 to 0.01) nor was there any difference in the incidence of new cerebral lesions on DW-MRI or contralateral DW-MRI lesions. In patients undergoing CAS, both D-EPD and P-EPD provide similar levels of protection from peri-procedural stroke and 30 days mortality. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
High-density polyethylene pipe: A new material for pass-by passive integrated transponder antennas
Kazyak, David C.; Zydlewski, Joseph D.
2012-01-01
Pass-by passive integrated transponder (PIT) antennas are widely used to study the movements of fish in streams. At many sites, stream conditions make it difficult to maintain antennas and obtain a continuous record of movement. We constructed pass-by PIT antennas by using high-density polyethylene (HDPE) and found them to be robust to high flows and winter ice flows. Costs for HDPE antennas were similar to those of traditional polyvinyl chloride (PVC) antennas, although construction was somewhat more complicated. At sites where PVC antennas are frequently damaged, HDPE is a durable and economical alternative for PIT antenna construction.
Xiao, Mingyue; Lu, Xiao; Li, Jianan; Li, Ling; Li, Yongxue
2014-04-01
Ischaemia-induced angiogenesis promises to improve neovascularization by delivery of angiogenic factors or endothelial progenitor cells (EPCs) to cardiac ischaemic areas. In order to avoid the risk of excessive myocardial ischaemia, therefore, we hypothesized that physiological ischaemic training (PIT) of normal skeletal muscle might contribute to myocardial angiogenesis via nitric oxide mediated mobilization of EPCs from the bone marrow in the established rabbit model of controllable myocardial ischaemia. The rabbits were grouped by sham-operation, myocardial ischaemia without PIT, PIT and PIT with pretreatment with the endothelial nitric oxide synthase (eNOS) inhibitor L-nitroarginine methyl ester (L-NAME). Controlled myocardial ischaemia was modelled by a water balloon constrictor implanted on the left ventricular branch in a rabbit. The PIT procedure included three cycles of 3 min of cuff inflation followed by 5 min of deflation on hind limbs of the rabbits for 4 weeks. At the endpoints, circulating EPCs (CD34/Flk-1) were measured by fluorescence-activated cell sorter; capillary density, by immunohistochemistry; blood flow, by a microsphere technique; endothelial nitric oxide synthase (eNOS) mRNA and protein, by real-time reverse transcriptase (RT)-PCR and Western blotting. The mRNA levels of eNOS were significantly higher in the PIT and L-NAME groups than in the sham-operation group (P < 0.05). Phospho-eNOS protein expression was higher in the PIT group than in the sham-operation and myocardial ischaemia without PIT groups (P < 0.05), and the effect was inhibited by L-NAME pretreatment (P < 0.05). Compared with sham-operation and myocardial ischaemia without PIT groups, the PIT group had the highest EPC count (P < 0.001), and the increase of capillary density (P < 0.01) and collateral blood flow (P < 0.05) in the ischaemic myocardium was consistent with the finding of EPC count. These effects were also inhibited by pretreatment with the eNOS inhibitor L-NAME. Capillary density and collateral blood flow were highly correlated with the increase of EPC count (r = 0.913 and r = 0.929, respectively, P = 0.000). PIT improved EPC mobilization and contributed to compensatory neovascularization via eNOS-related pathway. These results might support the future development of strategies for therapeutic neovascularization.
NASA Astrophysics Data System (ADS)
Hussain, Riaz; Tabassum, Sobia; Gilani, Mazhar Amjad; Ahmed, Ejaz; Sharif, Ahsan; Manzoor, Faisal; Shah, Asma Tufail; Asif, Anila; Sharif, Faiza; Iqbal, Farasat; Siddiqi, Saadat Anwar
2016-02-01
Hydroxyapatite (HA) shows diverse biomedical applications as bone filler and coating material for metal implants to enhance osteoconduction. Four different PVAHA composites were synthesized in situ by an economical co-precipitation wet methodology. The FTIR spectra of PVAHA composites showed characteristic signals of HA and PVA. The BET surface area of PVAHA composites were in range of 41.3-63.7 m2/g. The composites showed type IV nitrogen adsorption/desorption isotherm, a characteristic for mesoporous material. The pore diameter range (6.3-8.1 nm) of PVAHA composites also confirmed their mesoporous nature. The Barrett-Joyner-Halenda (BJH) pore size distribution curves indicated a narrow pore size distribution. To obtain a homogeneous crack free coating with EPD on stainless steel (SS) plates, different parameters such as PVA percentages in PVAHA composites, solvent, deposition time and voltage were optimized. The PVAHA composites were stable after EPD as confirmed by FTIR spectra recorded before and after EPD. The SEM images of the coating showed a homogeneous morphology. The thickness of the coating was controlled by varying voltage and time. The best results were obtained with c-PVAHA composite at 30 volts for 5-10 min and current density was around 4.5 to 5 mA. The adhesion strength of c-PVAHA coating was measured by using ASTM standard F1044-99. The average value was approximately 9.328 ± 1.58 MPa.
Enzyme-potentiated desensitization in otolaryngic allergy.
Pulec, Jack L
2002-03-01
This is a preliminary report of a new method of treating otolaryngic allergy with enzyme-potentiated desensitization (EPD). The nature of EPD and its use in otolaryngology are described. Thirty-six patients have been treated and followed in a private medical practice since February 1997. This article reviews the clinical features of EPD and provides six cases as examples; the clinical features described include allergic rhinitis, serous otitis media, asthma, dermatitis, fixed food allergy, and Ménière's disease. EPD is an effective technique for the treatment of otolaryngic allergy and offers advantages over conventional techniques.
Evaluation of the Edinburgh Post Natal Depression Scale using Rasch analysis
Pallant, Julie F; Miller, Renée L; Tennant, Alan
2006-01-01
Background The Edinburgh Postnatal Depression Scale (EPDS) is a 10 item self-rating post-natal depression scale which has seen widespread use in epidemiological and clinical studies. Concern has been raised over the validity of the EPDS as a single summed scale, with suggestions that it measures two separate aspects, one of depressive feelings, the other of anxiety. Methods As part of a larger cross-sectional study conducted in Melbourne, Australia, a community sample (324 women, ranging in age from 18 to 44 years: mean = 32 yrs, SD = 4.6), was obtained by inviting primiparous women to participate voluntarily in this study. Data from the EPDS were fitted to the Rasch measurement model and tested for appropriate category ordering, for item bias through Differential Item Functioning (DIF) analysis, and for unidimensionality through tests of the assumption of local independence. Results Rasch analysis of the data from the ten item scale initially demonstrated a lack of fit to the model with a significant Item-Trait Interaction total chi-square (chi Square = 82.8, df = 40; p < .001). Removal of two items (items 7 and 8) resulted in a non-significant Item-Trait Interaction total chi-square with a residual mean value for items of -0.467 with a standard deviation of 0.850, showing fit to the model. No DIF existed in the final 8-item scale (EPDS-8) and all items showed fit to model expectations. Principal Components Analysis of the residuals supported the local independence assumption, and unidimensionality of the revised EPDS-8 scale. Revised cut points were identified for EPDS-8 to maintain the case identification of the original scale. Conclusion The results of this study suggest that EPDS, in its original 10 item form, is not a viable scale for the unidimensional measurement of depression. Rasch analysis suggests that a revised eight item version (EPDS-8) would provide a more psychometrically robust scale. The revised cut points of 7/8 and 9/10 for the EPDS-8 show high levels of agreement with the original case identification for the EPDS-10. PMID:16768803
Montazeri, Ali; Torkan, Behnaz; Omidvari, Sepideh
2007-04-04
The Edinburgh Postnatal Depression Scale (EPDS) is a widely used instrument to measure postnatal depression. This study aimed to translate and to test the reliability and validity of the EPDS in Iran. The English language version of the EPDS was translated into Persian (Iranian language) and was used in this study. The questionnaire was administered to a consecutive sample of 100 women with normal (n = 50) and caesarean section (n = 50) deliveries at two points in time: 6 to 8 weeks and 12 to 14 weeks after delivery. Statistical analysis was performed to test the reliability and validity of the EPDS. Overall 22% of women at time 1 and 18% at time 2 reported experiencing postpartum depression. In general, the Iranian version of the EPDS was found to be acceptable to almost all women. Cronbach's alpha coefficient (to test reliability) was found to be 0.77 at time 1 and 0.86 at time 2. In addition, test-rest reliability was performed and the intraclass correlation coefficient was found to be 0.80. Validity as performed using known groups comparison showed satisfactory results. The questionnaire discriminated well between sub-groups of women differing in mode of delivery in the expected direction. The factor analysis indicated a three-factor structure that jointly accounted for 58% of the variance. This preliminary validation study of the Iranian version of the EPDS proved that it is an acceptable, reliable and valid measure of postnatal depression. It seems that the EPDS not only measures postpartum depression but also may be measuring something more.
Microcrater investigations on lunar rock 12002
NASA Technical Reports Server (NTRS)
Hartung, J. B.; Hodges, F.; Horz, F.; Storzer, D.
1975-01-01
Relative ages of 26 submillimeter-sized pits from an equilibrium population in rock 12002 were measured by determining the densities of pits 0.7 microns in diameter and larger on the submillimeter-sized pits. Production rates for 0.7 micron diameter pits were determined from solar-flare track exposure age measurements, and the data for rock 12002 are consistent with previously obtained data for sample 15205 if a lower meteoroid flux prevailed in the past. Metal mounds or spherules within a microcrater pit glass were found to have a meteoritic composition, and an impact lining consisting of protruding crystals was observed. The crystals apparently developed during exposure to space immediately after the 200-micron diameter pit was formed by impact into an olivine grain.
Seedling and Sapling Dynamics of Treefall Pits in Puerto Rico1
Lawrence R. Walker
2000-01-01
Seedling and sapling dynamics in a Puerto Rican rain forest were compared between forest understory and soil pits created by the uprooting of 27 trees during Hurricane Hugo. Soil N and P, organic matter, and soil moisture were lower and bulk densities were higher in the disturbed mineral soils of the pits than in undisturbed forest soils ten months after the hurricane...
Jeon, Han Ho; Youn, Young Hoon; Rhee, Kwangwon; Kim, Jie-Hyun; Park, Hyojin; Conklin, Jeffrey L
2014-02-01
Esophageal transit scintigraphy (ETS) and esophagography have long been used to evaluate patients with achalasia. The objectives of our study were to evaluate the efficacy of endoscopic pneumatic dilatation (EPD) as treatment for Koreans with achalasia and to determine which findings from ETS and esophagography predict successful treatment of achalasia. Patients with achalasia who were treated by EPD between April 2002 and January 2012 were recruited. We defined the success of EPD as 6 months or more of clinical remission without symptoms or a decrease in the Eckardt scores by at least two points and a total Eckardt score not exceeding 3. We reviewed the percentage of maximum scintigraphic activity retained in the esophagus at 30 s (R 30) and the post-PD rate of reduction of R 30 ((Pre R 30 - Post R 30)/Pre R 30 × 100) by ETS. Possible predictive factors determined by ETS and esophagography were analyzed. Our study included 53 eligible patients. The median symptom score (Eckardt score) was 5 (4-8). R 30 and T 1/2 were, respectively, 61.8 % and 38.5 min before EPD and 20 % and 4.19 min after EPD. Successful EPD was achieved for 40 of 53 (75.47 %) patients. Age (≥40, p = 0.027) and post-PD rate of reduction of R 30 (>20 %, p = 0.003) were best prognostic indicators of clinical success. There were no perforations related to EPD. Older age and a post-PD rate of reduction of R 30 were strongly associated with better outcomes. Examination with ETS before and after EPD can be used to objectively assess a patient's short-term response to EPD.
Chen, Helen; Bautista, Dianne; Ch'ng, Ying Chia; Li, Wenyun; Chan, Edwin; Rush, A John
2013-06-01
The Edinburgh Postnatal Depression Scale (EPDS) may not be a uniformly valid postnatal depression (PND) screen across populations. We evaluated the performance of a Chinese translation of 10-item (HK-EPDS) and six-item (HK-EPDS-6) versions in post-partum women in Singapore. Chinese-speaking post-partum obstetric clinic patients were recruited for this study. They completed the HK-EPDS, from which we derived the six-item HK-EPDS-6. All women were clinically assessed for PND based on Diagnostic and Statistical Manual, Fourth Edition-Text Revision criteria. Receiver-operator curve (ROC) analyses and likelihood ratio computations informed scale cutoff choices. Clinical fitness was judged by thresholds for internal consistency [α ≥ 0.70] and for diagnostic performance by true-positive rate (>85%), false-positive rate (≤10%), positive likelihood ratio (>1), negative likelihood ratio (<0.2), area under the ROC curve (AUC, ≥90%) and effect size (≥0.80). Based on clinical interview, prevalence of PND was 6.2% in 487 post-partum women. HK-EPDS internal consistency was 0.84. At 13 or more cutoff, the true-positive rate was 86.7%, false-positive rate 3.3%, positive likelihood ratio 26.4, negative likelihood ratio 0.14, AUC 94.4% and effect size 0.81. For the HK-EPDS-6, internal consistency was 0.76. At 8 or more cutoff, we found a true-positive rate of 86.7%, false-positive rate 6.6%, positive likelihood ratio 13.2, negative likelihood ration 0.14, AUC 92.9% and effect size 0.98. The HK-EPDS (cutoff ≥13) and HK-EPDS6 (cutoff ≥8) are fit for PND screening for general population post-partum women. The brief six-item version appears to be clinically suitable for quick screening in Chinese speaking women. Copyright © 2013 Wiley Publishing Asia Pty Ltd.
NASA Astrophysics Data System (ADS)
Pichan, Karuppasamy; Muthu, Senthil Pandian; Perumalsamy, Ramasamy
2017-09-01
The organic single crystal of piperazinium bis(4-hydroxybenzenesulphonate) (P4HBS) was grown by slow evaporation solution technique (SEST) at room temperature. The lattice parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis. Functional groups of P4HBS crystal were confirmed by FTIR spectrum analysis. The optical quality of the grown crystal was identified by the UV-Vis NIR spectrum analysis. The grown crystal has good optical transmittance in the range of 410-1100 nm. In photoluminescence spectrum, sharp emission peaks are observed, which indicates the ultraviolet (UV) emission. The photoconductivity study reveals that the grown crystal has negative photoconductive nature. The thermal behaviour of the P4HBS crystal was investigated by thermogravimetric and differential thermal analysis (TG-DTA). The mechanical stability of grown crystal was analyzed and the indentation size effect (ISE) was explained by Hays-Kendall's (HK) approach and proportional specimen resistance model (PSRM). Chemical etching study was carried out and the etch pit density (EPD) was calculated. The dielectric constant (ε‧) and dielectric loss (tan δ) as a function of frequency were measured for the grown crystal. The solid state parameters such as valence electron, plasma energy, Penn gap and Fermi energy were evaluated theoretically for the P4HBS using the empirical relation. The estimated values are used to calculate the electronic polarizability. The third-order nonlinear optical properties such as nonlinear refractive index (n2), absorption co-efficient (β) and susceptibility (χ(3)) were studied by Z-scan technique at 632.8 nm using He-Ne laser.
Electrophoretic Deposition of Chitosan/45S5 Bioactive Glass Composite Coatings Doped with Zn and Sr
Miola, Marta; Verné, Enrica; Ciraldo, Francesca Elisa; Cordero-Arias, Luis; Boccaccini, Aldo R.
2015-01-01
In this research work, the original 45S5 bioactive glass was modified by introducing zinc and/or strontium oxide (6 mol%) in place of calcium oxide. Sr was added for its ability to stimulate bone formation and Zn for its role in bone metabolism, antibacterial properties, and anti-inflammatory effect. The glasses were produced by means of melting and quenching process. SEM and XRD analyses evidenced that Zr and Sr introduction did not modify the glass structure and morphology while compositional analysis (EDS) demonstrated the effective incorporation of these elements in the glass network. Bioactivity test in simulated body fluid (SBF) up to 1 month evidenced a reduced bioactivity kinetics for Zn-doped glasses. Doped glasses were combined with chitosan to produce organic/inorganic composite coatings on stainless steel AISI 316L by electrophoretic deposition (EPD). Two EPD processes were considered for coating development, namely direct current EPD (DC-EPD) and alternating current EPD (AC-EPD). The stability of the suspension was analyzed and the deposition parameters were optimized. Tape and bending tests demonstrated a good coating-substrate adhesion for coatings containing 45S5-Sr and 45S5-ZnSr glasses, whereas the adhesion to the substrate decreased by using 45S5-Zn glass. FTIR analyses demonstrated the composite nature of coatings and SEM observations indicated that glass particles were well integrated in the polymeric matrix, the coatings were fairly homogeneous and free of cracks; moreover, the AC-EPD technique provided better results than DC-EPD in terms of coating quality. SEM, XRD analyses, and Raman spectroscopy, performed after bioactivity test in SBF solution, confirmed the bioactive behavior of 45S5-Sr-containing coating while coatings containing Zn exhibited no hydroxyapatite formation. PMID:26539431
Anding, Jana Eos; Röhrle, Bernd; Grieshop, Melita; Schücking, Beate; Christiansen, Hanna
2016-01-15
Postnatal depression affects a significant number of parents; however, its co-occurrence in mothers and fathers has not been studied extensively. Identifying predictors and correlates of postnatal depressive symptoms can help develop effective interventions. Questionnaires on several socio-demographic and psychosocial factors were administered to 276 couples within two weeks after birth. Depressive symptoms in mothers and fathers were assessed using the Edinburgh Postnatal Depression Scale (EPDS). After calculating the correlation coefficient between mothers and fathers' EPDS scores, univariate and multivariate linear regression analyses were performed to identify significant correlates of postnatal depressive symptoms in mothers and fathers. Prevalence of maternal and paternal postnatal depressive symptoms was 15.9% (EPDS>12) and 5.4% (EPDS>10), respectively. There was a moderate positive correlation between mothers and fathers' EPDS scores (r=.30, p<.001). Multivariate analyses indicated that parental stress was the strongest predictor for maternal and paternal postnatal depressive symptoms. Pregnancy- and birth-related distress and partners' EPDS scores were also associated with depressive symptoms in both parents. Relationship satisfaction was only inversely related with fathers' EPDS scores, while mothers' EPDS scores were additionally associated with critical life events, history of childhood violence, and birth-related physiological complaints. Since information about participation rates (those who declined) is unavailable, we cannot rule out sampling bias. Further, some psychosocial factors were assessed using single items. Since co-occurrence of depressive symptoms in mothers and fathers is high, developing and evaluating postnatal depression interventions for couples may be beneficial. Interventions to reduce parenting stress may help prevent parental postnatal depression. Copyright © 2015 Elsevier B.V. All rights reserved.
Ippoliti, F; Ragno, V; Del Nero, A; McEwen, L M; McEwen, H; Businco, L
1997-05-01
EPD is a method of preventive immunotherapy which employs b-glucuronidase as a biological response modifier. Plasma IL-6 and IL-10 were measured before a single injection of EPD, 24 hours later and 15 days after in a group of 17 children suffering from grass pollen asthma. 17 normal untreated children were used as controls. Although the study was conducted before the grass pollen season when the allergic children were free of symptoms, their plasma IL-6 and IL-10 were significantly elevated before the injection of EPD. 24 hours after treatment the plasma IL-10 had increased significantly and there was also a slight rise in IL-6. 15 days after treatment IL-6 had fallen to normal but IL-10 was still elevated. These findings suggest antigen-specific and non-specific mechanisms by which EPD may produce clinical improvement.
NASA Astrophysics Data System (ADS)
Kim, K. M.; Kang, M. S.; Kwon, H. W.; Lee, J. G.; Yu, J. H.
2018-05-01
Feasibility of the electrophoresis deposition (EPD) technique for homogeneous and adhesive deposition of DyF3 particles on the Nd-Fe-B-type particles was studied, and coercivity enhancement in the diffusion-treated Nd-Fe-B-type particles deposited with DyF3 by EPD was investigated. HDDR-treated Nd12.5Fe80.6B6.4Ga0.3Nb0.2 particles were deposited with DyF3 particles by EPD. More homogeneous and adhesive deposition of DyF3 particles on the surface of Nd-Fe-B particles was made by the EPD with respect to conventional dip-coating, and this led to more active and homogeneous diffusion of Dy. More profound coercivity enhancement was achieved in the diffusion-treated Nd-Fe-B-type particles deposited with DyF3 by EPD compared to dip-coated particles.
NASA Astrophysics Data System (ADS)
Wang, Min-Shuai; Huang, Xiao-Jing
2013-08-01
We present a new method of making a textured V-pit surface for improving the light extraction efficiency in GaN-based light-emitting diodes and compare it with the usual low-temperature method for p-GaN V-pits. Three types of GaN-based light-emitting diodes (LEDs) with surface V-pits in different densities and regions were grown by metal—organic chemical vapor deposition. We achieved the highest output power and lowest forward voltage values with the p-InGaN V-pit LED. The V-pits enhanced the light output power values by 1.45 times the values of the conventional LED owing to an enhancement of the light scattering probability and an effective reduction of Mg-acceptor activation energy. Moreover, this new technique effectively solved the higher forward voltage problem of the usual V-pit LED.
Environmental Protection Department's well inventory through the second quarter of 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, C.D.
This report is an inventory of the wells recorded in Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) documents since the startup of the Savannah River Site (SRS) and includes wells monitored by special request and SRS research wells. Wells listed in this inventory are monitoring wells unless otherwise indicated. The purpose of this report is as follows: to provide a historical record of the wells that EPD/EMS has monitored, to provide a document containing a list of wells that are currently in the EPD/EMS Groundwater Monitoring Program, and to provide pertinent information about all wells listed in EPD/EMS documents.
Environmental Protection Department`s well inventory through the second quarter of 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, C.D.
This report is an inventory of the wells recorded in Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) documents since the startup of the Savannah River Site (SRS) and includes wells monitored by special request and SRS research wells. Wells listed in this inventory are monitoring wells unless otherwise indicated. The purpose of this report is as follows: to provide a historical record of the wells that EPD/EMS has monitored, to provide a document containing a list of wells that are currently in the EPD/EMS Groundwater Monitoring Program, and to provide pertinent information about all wells listed in EPD/EMS documents.
Bina, Rena; Harrington, Donna
2016-04-01
The Edinburgh Postnatal Depression Scale (EPDS) was originally created as a uni-dimensional scale to screen for postpartum depression (PPD); however, evidence from various studies suggests that it is a multi-dimensional scale measuring mainly anxiety in addition to depression. The factor structure of the EPDS seems to differ across various language translations, raising questions regarding its stability. This study examined the factor structure of the Hebrew version of the EPDS to assess whether it is uni- or multi-dimensional. Seven hundred and fifteen (n = 715) women were screened at 6 weeks postpartum using the Hebrew version of the EPDS. Confirmatory factor analysis (CFA) was used to test four models derived from the literature. Of the four CFA models tested, a 9-item two factor model fit the data best, with one factor representing an underlying depression construct and the other representing an underlying anxiety construct. for Practice The Hebrew version of the EPDS appears to consist of depression and anxiety sub-scales. Given the widespread PPD screening initiatives, anxiety symptoms should be addressed in addition to depressive symptoms, and a short scale, such as the EPDS, assessing both may be efficient.
Comparison of Neurocognitive Outcomes after Carotid Endarterectomy and Carotid Artery Stenting.
Kim, Jerry J; Schwartz, Samuel; Wen, Johnny; deVirgilio, Christian; Lobue, Abeline; Walot, Irwin; Koopmann, Matthew; Donayre, Carlos; White, Rodney A
2015-10-01
Cognitive and emotional outcomes after carotid endarterectomy (CEA) and carotid artery stenting with embolic protection device (CAS + EPD) are not clear. Patients were entered prospectively into a United States Food and Drug Administration-approved single-center physician-sponsored investigational device exemption between 2004 and 2010 and received either CEA or CAS + EPD. Patients underwent cognitive testing preprocedure and at 6, 12, and 60 months postprocedure. Cognitive domains assessed included attention, memory, executive, motor function, visual spatial functioning, language, and processing speed. Beck Depression and anxiety scales were also compared. There were a total of 38 patients that met conventional indications for carotid surgery (symptomatic with ≥50% stenosis or asymptomatic with ≥70% stenosis)-12 patients underwent CEA, whereas 26 patients underwent CAS + EPD. Both CEA and CAS + EPD patients showed postprocedure improvement in memory and executive function. No differences were seen at follow-up in regards to emotional dysfunction (depression and anxiety), attention, visual spatial functioning, language, motor function, and processing speed. Only two patients underwent neuropsychiatric testing at 60 months-these CAS + EPD patients showed sustained improvement in memory, visual spatial, and executive functions. In conclusion, cognitive and emotional outcomes were similar between CEA and CAS + EPD patients.
A crossover study of rosuvastatin and pitavastatin in patients with type 2 diabetes.
Yanagi, Kazunori; Monden, Tsuyoshi; Ikeda, Shiori; Matsumura, Mihoko; Kasai, Kikuo
2011-02-01
The effects of a low dose of rosuvastatin (ROS) and pitavastatin (PIT) on lipid profiles and inflammation markers were assessed in subjects with type 2 diabetes mellitus. A total of 90 Japanese type 2 diabetes patients with hyperlipidemia (low-density lipoprotein cholesterol [LDL-C] ≥140 mg/dL) were enrolled in this study. They were randomly assigned to four groups with open-label treatment with ROS (2.5 mg daily) or PIT (2 mg daily); two groups were sequentially treated with both drugs, with crossover of medication after 12 weeks, and the other two groups underwent treatment with either ROS or PIT for 24 weeks. The primary endpoints were the percentage changes in LDL-C, high-density lipoprotein cholesterol (HDL-C) and triglyceride, and the LDL-C/HDL-C ratio. Both ROS and PIT lowered LDL-C and triglyceride, and increased HDL-C. In particular, significantly greater reduction in LDL-C was seen with ROS (-44.1%) than with PIT (-36.9%, P<0.01) in the crossover group from ROS to PIT, and the same result was detected in the crossover group from PIT (-34.8%) to ROS (-44.7%). The ratio of LDL-C/HDL-C was significantly reduced with ROS treatment (from 3.45 to 1.85) compared with that with PIT (from 3.45 to 2.22, P<0.01). Both ROS and PIT lowered plasma levels of high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor (TNF)-alpha, and plasminogen activator inhibitor-1 (PAI-1). In addition, the hsCRP level with the administration of ROS was significantly improved compared with the administration of PIT. There was no significant correlation between changes in LDL-C and hsCRP, TNF-alpha, and PAI-1 levels. ROS and PIT did not have an adverse effect on glycemic control in type 2 diabetes patients. Therapy with both statins improved lipid profiles and reduced proinflammatory responses; however, 2.5 mg of ROS have a potent LDL-C-lowering and hsCRP-lowering effect compared with 2 mg of PIT in patients with diabetes.
Sano, Yuzou; Morris, Hugh; Shimada, Hiroshi; Ronse De Craene, Louis P.; Jansen, Steven
2011-01-01
Background and Aims Imperforate tracheary elements (ITEs) in wood of vessel-bearing angiosperms may or may not transport water. Despite the significance of hydraulic transport for defining ITE types, the combination of cell structure with water transport visualization in planta has received little attention. This study provides a quantitative analysis of structural features associated with the conductive vs. non-conductive nature of ITEs. Methods Visualization of water transport was studied in 15 angiosperm species by dye injection and cryo-scanning electron microscopy. Structural features of ITEs were examined using light and electron microscopy. Key Results ITEs connected to each other by pit pairs with complete pit membranes contributed to water transport, while cells showing pit membranes with perforations up to 2 µm were hydraulically not functional. A close relationship was found between pit diameter and pit density, with both characters significantly higher in conductive than in non-conductive cells. In species with both conductive and non-conductive ITEs, a larger diameter was characteristic of the conductive cells. Water transport showed no apparent relationship with the length of ITEs and vessel grouping. Conclusions The structure and density of pits between ITEs represent the main anatomical characters determining water transport. The pit membrane structure of ITEs provides a reliable, but practically challenging, criterion to determine their conductive status. It is suggested that the term tracheids should strictly be used for conductive ITEs, while fibre-tracheids and libriform fibres are non-conductive. PMID:21385773
Zhao, Xin; Ciovati, G.; Bieler, T. R.
2010-12-15
The performance of superconducting radio-frequency (SRF) resonant cavities made of bulk niobium is limited by nonlinear localized effects. Surface analysis of regions of higher power dissipation is thus of intense interest. Such areas (referred to as “hotspots”) were identified in a large-grain single-cell cavity that had been buffered-chemical polished and dissected for examination by high resolution electron microscopy, electron backscattered diffraction microscopy (EBSD), and optical microscopy. Pits with clearly discernible crystal facets were observed in both “hotspot” and “coldspot” specimens. The pits were found in-grain, at bicrystal boundaries, and on tricrystal junctions. They are interpreted as etch pits induced bymore » crystal defects (e.g. dislocations). All coldspots examined had a qualitatively lower density of etch pits or relatively smooth tricrystal boundary junctions. EBSD mapping revealed the crystal orientation surrounding the pits. Locations with high pit density are correlated with higher mean values of the local average misorientation angle distributions, indicating a higher geometrically necessary dislocation content. In addition, a survey of the samples by energy dispersive x-ray analysis did not show any significant contamination of the samples’ surface. In conclusion, the local magnetic field enhancement produced by the sharp-edge features observed on the samples is not sufficient to explain the observed degradation of the cavity quality factor, which starts at peak surface magnetic field as low as 20 mT.« less
Kim, Ki-Tae; Lee, Jung-Hee; Kim, Young-Sik
2017-01-01
Stainless steels have good corrosion resistance in many environments but welding or aging can decrease their resistance. This work focused on the effect of aging time and ultrasonic nano-crystal surface modification on the passivation behavior of 316L stainless steel. In the case of slightly sensitized 316L stainless steel, increasing the aging time drastically decreased the pitting potential, increased the passive current density, and decreased the resistance of the passive film, even though aging did not form chromium carbide and a chromium depletion zone. This behavior is due to the micro-galvanic corrosion between the matrix and carbon segregated area, and this shows the importance of carbon segregation in grain boundaries to the pitting corrosion resistance of stainless steel, in addition to the formation of the chromium depletion zone. UNSM (Ultrasonic Nano Crystal Surface Modification)-treatment to the slightly sensitized 316L stainless steel increased the pitting potential, decreased the passive current density, and increased the resistance of the passive film. However, in the case of heavily sensitized 316L stainless steel, UNSM-treatment decreased the pitting potential, increased the passive current density, and decreased the resistance of the passive film. This behavior is due to the dual effects of the UNSM-treatment. That is, the UNSM-treatment reduced the carbon segregation, regardless of whether the stainless steel 316L was slightly or heavily sensitized. However, since this treatment made mechanical flaws in the outer surface in the case of the heavily sensitized stainless steel, UNSM-treatment may eliminate chromium carbide, and this flaw can be a pitting initiation site, and therefore decrease the pitting corrosion resistance. PMID:28773067
Kim, Ki-Tae; Lee, Jung-Hee; Kim, Young-Sik
2017-06-27
Stainless steels have good corrosion resistance in many environments but welding or aging can decrease their resistance. This work focused on the effect of aging time and ultrasonic nano-crystal surface modification on the passivation behavior of 316L stainless steel. In the case of slightly sensitized 316L stainless steel, increasing the aging time drastically decreased the pitting potential, increased the passive current density, and decreased the resistance of the passive film, even though aging did not form chromium carbide and a chromium depletion zone. This behavior is due to the micro-galvanic corrosion between the matrix and carbon segregated area, and this shows the importance of carbon segregation in grain boundaries to the pitting corrosion resistance of stainless steel, in addition to the formation of the chromium depletion zone. UNSM (Ultrasonic Nano Crystal Surface Modification)-treatment to the slightly sensitized 316L stainless steel increased the pitting potential, decreased the passive current density, and increased the resistance of the passive film. However, in the case of heavily sensitized 316L stainless steel, UNSM-treatment decreased the pitting potential, increased the passive current density, and decreased the resistance of the passive film. This behavior is due to the dual effects of the UNSM-treatment. That is, the UNSM-treatment reduced the carbon segregation, regardless of whether the stainless steel 316L was slightly or heavily sensitized. However, since this treatment made mechanical flaws in the outer surface in the case of the heavily sensitized stainless steel, UNSM-treatment may eliminate chromium carbide, and this flaw can be a pitting initiation site, and therefore decrease the pitting corrosion resistance.
Shrestha, Sumitra Devi; Pradhan, Rina; Tran, Thach D; Gualano, Rosa C; Fisher, Jane R W
2016-04-04
The Edinburgh Postnatal Depression Scale (EPDS), originally developed in Britain, is one of the most widely used screening instruments for assessing symptoms of the Perinatal Common Mental Disorders (PCMDs) of depression and anxiety. However, its potential to detect PCMDs in culturally diverse low- and lower-middle income countries (LALMICs) is unclear. This systematic review aimed to appraise formally validated local language versions of the EPDS from these resource-constrained settings. Following the PRISMA protocol, we searched MEDLINE-OVID, CINAHL-Plus and PUBMED to identify studies reporting translation, cultural adaptation and formal validation of the EPDS to detect PCMDs among women in LALMICs. The quality of the studies meeting inclusion criteria was assessed using standard criteria and a new process-based criteria; which was developed specifically for this study. We identified 1281 records among which 16 met inclusion criteria; three further papers were identified by hand-searching reference lists. The publications reported findings from 12 LALMICs in 14 native languages. Most of these local language versions of the EPDS (LLV-EPDS) had lower precision for identifying true cases of PCMDs among women in the general perinatal population compared to the original English version. Only one study met all criteria for culturally sensitive translation, the others had not established the comprehensibility of the local version amongst representative groups of women in pre-testing. Many studies tested the LLV-EPDS only amongst convenience samples recruited at single health facilities. Diagnostic interviews for confirmation of mental disorders could have been influenced by the mental health professionals' lack of blinding to the initial screening results. Additionally, even when diagnostic-interviews were carried out in the local language, questions might not have been understood as most studies followed standard diagnostic protocol which had not been culturally adapted. Most of the LLV-EPDS from non-English speaking low- and middle-income-countries did not meet all criteria for formal validation of a screening instrument. Psychometric properties of LLV-EPDS could be enhanced by adopting the new process-based criteria for translation, adaptation and validation.
COMPARISON OF SOME PROPERTIES OF MINESOILS AND CONTIGUOUS NATURAL SOILS
Four minesoil pits located within the disturbed area and four natural soil pits located in adjacent undisturbed areas were described and sampled. Bulk densities were determined at ten randomly located sites. Microlysimeters were subsequently installed at these sites and used to d...
NASA Astrophysics Data System (ADS)
Feng, Y. P.; Sinha, S. K.; Melendres, C. A.; Lee, D. D.
1996-02-01
We have studied the electrochemically-induced pitting process on a Cu electrode in NaHCO 3 solution using in-situ X-ray off-specular reflectivity measurements. The morphology and growth dynamics of the localized corrosion sites or pits were studied as the applied potential was varied from the cathodic region where the Cu surface is relatively free of oxide films to the anodic region where surface roughening occurs by general corrosion with concomitant formation of an oxide film. Quantitative analysis of the experimental results indicates that early pitting proceeds in favor of nucleation of pit clusters over individual pit growth. It was found that the lateral distribution of the pits is not random but exhibits a short-range order as evidenced by the appearance of a side peak in the transverse off-specular reflectivity. The position, height, and width of the peak was modeled to yield the average size, nearest-neighbor distance (within any one of the clusters), and over-all density of the pits averaged over the entire illuminated surface. In addition, measurements of the longitudinal off-specular reflectivity indicate a bimodal depth distribution for the pits, suggesting a “film breaking” type of pitting mechanism.
Smith-Nielsen, Johanne; Steele, Howard; Mehlhase, Heike; Cordes, Katharina; Steele, Miriam; Harder, Susanne; Væver, Mette Skovgaard
2015-12-01
Underlying persistent psychological difficulties have been found to moderate potential adverse effects of maternal postpartum depression (PPD) on parenting and infant development. The authors examined whether mothers presenting postpartum depressive symptoms showed higher levels of personality pathology and more insecure state of mind regarding attachment compared to nondepressed mothers. Participants (N = 85) were assessed with the Edinburgh Postnatal Depression Scale (EPDS), the Present State Examination, the Adult Attachment Interview, and the Structured Clinical Interview for DSM-IV Axis II. Mothers with high EPDS scores were more likely to have a preoccupied insecure state of mind and to have personality disorder compared with mothers scoring below clinical cutoff. Furthermore, multiple regression analysis showed that personality disorder and AAI classification were independently related to EPDS score, and that these two factors together accounted for 48% of the variance in EPDS score. Findings are discussed in terms of heterogeneity in PPD populations and underline the importance of examining potential coexisting psychological difficulties when studying PPD.
NASA Astrophysics Data System (ADS)
Karuppasamy, P.; Senthil Pandian, Muthu; Ramasamy, P.; Verma, Sunil
2018-05-01
The optically good quality single crystals of triphenylphosphine oxide 4-nitrophenol (TP4N) with maximum dimension of 15 × 10 × 5 mm3 were grown by slow evaporation solution technique (SEST) at room temperature. The cell dimensions of the grown TP4N crystal were confirmed by single crystal X-ray diffraction (SXRD) and the crystalline purity was confirmed and planes were indexed by powder X-ray diffraction (PXRD) analysis. Functional groups of TP4N crystal were confirmed by Fourier transform infrared (FTIR) spectral analysis. The optical transmittance of the grown crystal was determined by the UV-Vis NIR spectral analysis and it has good optical transparency in the entire visible region. The band tail (Urbach) energy of the grown crystal was analyzed and it appears to be minimum, which indicates that the TP4N has good crystallinity. The position of valence band (Ev) and conduction band (Ec) of the TP4N have been determined from the electron affinity energy (EA) and the ionization energy (EI) of its elements and using the optical band gap. The thermal behaviour of the grown crystal was investigated by thermogravimetric and differential thermal analysis (TG-DTA). Vickers microhardness analysis was carried out to identify the mechanical stability of the grown crystal and their indentation size effect (ISE) was explained by the Meyer's law (ML), Hays-Kendall's (HK) approach, proportional specimen resistance (PSR) model, modified PSR model (MPSR), elastic/plastic deformation (EPD) model and indentation induced cracking (IIC) model. Chemical etching study was carried out to find the etch pit density (EPD) of the grown crystal. Laser damage threshold (LDT) value was measured by using Nd:YAG laser (1064 nm). The dielectric permittivity (ε՛) and dielectric loss (tan δ) as a function of frequency was measured. The electronic polarizability (α) of the TP4N crystal was calculated. It is well matched to the value which was calculated from Clausius-Mossotti relation, Lorentz-Lorentz equation, optical band gap and coupled dipole method (CDM). The Z-scan technique was carried out using solid state laser (640 nm) to analyze the nonlinear optical properties of the TP4N crystal. It exhibits the self-defocusing and saturable absorbance effect during analysis of closed and open aperture respectively. The nonlinear optical parameters such as refractive index (n2), absorption coefficient (β) and the third order nonlinear optical susceptibility (χ(3)) were analyzed.
Defect sensitive etching of hexagonal boron nitride single crystals
NASA Astrophysics Data System (ADS)
Edgar, J. H.; Liu, S.; Hoffman, T.; Zhang, Yichao; Twigg, M. E.; Bassim, Nabil D.; Liang, Shenglong; Khan, Neelam
2017-12-01
Defect sensitive etching (DSE) was developed to estimate the density of non-basal plane dislocations in hexagonal boron nitride (hBN) single crystals. The crystals employed in this study were precipitated by slowly cooling (2-4 °C/h) a nickel-chromium flux saturated with hBN from 1500 °C under 1 bar of flowing nitrogen. On the (0001) planes, hexagonal-shaped etch pits were formed by etching the crystals in a eutectic mixture of NaOH and KOH between 450 °C and 525 °C for 1-2 min. There were three types of pits: pointed bottom, flat bottom, and mixed shape pits. Cross-sectional transmission electron microscopy revealed that the pointed bottom etch pits examined were associated with threading dislocations. All of these dislocations had an a-type burgers vector (i.e., they were edge dislocations, since the line direction is perpendicular to the [ 2 11 ¯ 0 ]-type direction). The pit widths were much wider than the pit depths as measured by atomic force microscopy, indicating the lateral etch rate was much faster than the vertical etch rate. From an Arrhenius plot of the log of the etch rate versus the inverse temperature, the activation energy was approximately 60 kJ/mol. This work demonstrates that DSE is an effective method for locating threading dislocations in hBN and estimating their densities.
NASA Astrophysics Data System (ADS)
Xiao, Wei; Xia, Hui; Fuh, Jerry Y. H.; Lu, Li
2010-05-01
CNT/MnO2 (birnessite-type) composite films have been successfully deposited on Ni-foil substrate via electrophoretic deposition (EPD). The unique EPD CNT/MnO2 composite film electrode shows enhanced electrical conductivity, good contact between composite films and the substrate and open porous structure, which makes the EPD composite films a promising electrode for high-power supercapacitors and lithium ion batteries.
Cortical dynamics and subcortical signatures of motor-language coupling in Parkinson's disease.
Melloni, Margherita; Sedeño, Lucas; Hesse, Eugenia; García-Cordero, Indira; Mikulan, Ezequiel; Plastino, Angelo; Marcotti, Aida; López, José David; Bustamante, Catalina; Lopera, Francisco; Pineda, David; García, Adolfo M; Manes, Facundo; Trujillo, Natalia; Ibáñez, Agustín
2015-07-08
Impairments of action language have been documented in early stage Parkinson's disease (EPD). The action-sentence compatibility effect (ACE) paradigm has revealed that EPD involves deficits to integrate action-verb processing and ongoing motor actions. Recent studies suggest that an abolished ACE in EPD reflects a cortico-subcortical disruption, and recent neurocognitive models highlight the role of the basal ganglia (BG) in motor-language coupling. Building on such breakthroughs, we report the first exploration of convergent cortical and subcortical signatures of ACE in EPD patients and matched controls. Specifically, we combined cortical recordings of the motor potential, functional connectivity measures, and structural analysis of the BG through voxel-based morphometry. Relative to controls, EPD patients exhibited an impaired ACE, a reduced motor potential, and aberrant frontotemporal connectivity. Furthermore, motor potential abnormalities during the ACE task were predicted by overall BG volume and atrophy. These results corroborate that motor-language coupling is mainly subserved by a cortico-subcortical network including the BG as a key hub. They also evince that action-verb processing may constitute a neurocognitive marker of EPD. Our findings suggest that research on the relationship between language and motor domains is crucial to develop models of motor cognition as well as diagnostic and intervention strategies.
Zhao, Ying; Kane, Irene; Wang, Jing; Shen, Beibei; Luo, Jianfeng; Shi, Shenxun
2015-03-30
The purpose of the present study was to evaluate antenatal depression screening employing two scales: the Postpartum Depression Screening Scale (PDSS) and Edinburgh Postnatal Depression Scale (EPDS) for the population of Chinese pregnant women with obstetric complications. A convenience sample of 842 Chinese pregnant women with complications participated in this study. The PDSS total score correlated strongly with the EPDS total score (r=0.652, p=0.000). Each tool performed extremely well for detecting major and major/minor depressions with PDSS resulting in a better psychometric performance than EPDS (p<0.01). If combined use, the recommended EPDS cut-off score was 8/9 for major depression, at which the sensitivity (71.6%) and specificity (87.6%) were the best, and the recommended PDSS cut-off score was 79/80 for major depression, along with its best sensitivity (86.4%) and specificity (100%). The study concluded that EPDS and PDSS appear to be reliable assessments for major and minor depression among the Chinese pregnant women with obstetric complications. Combined use of these tools should consider lower cutoff scores to reduce the misdiagnosis and improve the screening validity. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Streamlining environmental product declarations: a stage model
NASA Astrophysics Data System (ADS)
Lefebvre, Elisabeth; Lefebvre, Louis A.; Talbot, Stephane; Le Hen, Gael
2001-02-01
General public environmental awareness and education is increasing, therefore stimulating the demand for reliable, objective and comparable information about products' environmental performances. The recently published standard series ISO 14040 and ISO 14025 are normalizing the preparation of Environmental Product Declarations (EPDs) containing comprehensive information relevant to a product's environmental impact during its life cycle. So far, only a few environmentally leading manufacturing organizations have experimented the preparation of EPDs (mostly from Europe), demonstrating its great potential as a marketing weapon. However the preparation of EPDs is a complex process, requiring collection and analysis of massive amounts of information coming from disparate sources (suppliers, sub-contractors, etc.). In a foreseeable future, the streamlining of the EPD preparation process will require product manufacturers to adapt their information systems (ERP, MES, SCADA) in order to make them capable of gathering, and transmitting the appropriate environmental information. It also requires strong functional integration all along the product supply chain in order to ensure that all the information is made available in a standardized and timely manner. The goal of the present paper is two fold: first to propose a transitional model towards green supply chain management and EPD preparation; second to identify key technologies and methodologies allowing to streamline the EPD process and subsequently the transition toward sustainable product development
Relationship Between Foveal Cone Specialization and Pit Morphology in Albinism
Wilk, Melissa A.; McAllister, John T.; Cooper, Robert F.; Dubis, Adam M.; Patitucci, Teresa N.; Summerfelt, Phyllis; Anderson, Jennifer L.; Stepien, Kimberly E.; Costakos, Deborah M.; Connor, Thomas B.; Wirostko, William J.; Chiang, Pei-Wen; Dubra, Alfredo; Curcio, Christine A.; Brilliant, Murray H.; Summers, C. Gail; Carroll, Joseph
2014-01-01
Purpose. Albinism is associated with disrupted foveal development, though intersubject variability is becoming appreciated. We sought to quantify this variability, and examine the relationship between foveal cone specialization and pit morphology in patients with a clinical diagnosis of albinism. Methods. We recruited 32 subjects with a clinical diagnosis of albinism. DNA was obtained from 25 subjects, and known albinism genes were analyzed for mutations. Relative inner and outer segment (IS and OS) lengthening (fovea-to-perifovea ratio) was determined from manually segmented spectral domain-optical coherence tomography (SD-OCT) B-scans. Foveal pit morphology was quantified for eight subjects from macular SD-OCT volumes. Ten subjects underwent imaging with adaptive optics scanning light ophthalmoscopy (AOSLO), and cone density was measured. Results. We found mutations in 22 of 25 subjects, including five novel mutations. All subjects lacked complete excavation of inner retinal layers at the fovea, though four subjects had foveal pits with normal diameter and/or volume. Peak cone density and OS lengthening were variable and overlapped with that observed in normal controls. A fifth hyper-reflective band was observed in the outer retina on SD-OCT in the majority of the subjects with albinism. Conclusions. Foveal cone specialization and pit morphology vary greatly in albinism. Normal cone packing was observed in the absence of a foveal pit, suggesting a pit is not required for packing to occur. The degree to which retinal anatomy correlates with genotype or visual function remains unclear, and future examination of larger patient groups will provide important insight on this issue. PMID:24845642
Antenatal risk factors for postnatal depression: a large prospective study.
Milgrom, Jeannette; Gemmill, Alan W; Bilszta, Justin L; Hayes, Barbara; Barnett, Bryanne; Brooks, Janette; Ericksen, Jennifer; Ellwood, David; Buist, Anne
2008-05-01
This study measured antenatal risk factors for postnatal depression in the Australian population, both singly and in combination. Risk factor data were gathered antenatally and depressive symptoms measured via the beyondblue National Postnatal Depression Program, a large prospective cohort study into perinatal mental health, conducted in all six states of Australia, and in the Australian Capital Territory, between 2002 and 2005. Pregnant women were screened for symptoms of postnatal depression at antenatal clinics in maternity services around Australia using the Edinburgh Postnatal Depression Scale (EPDS) and a psychosocial risk factor questionnaire that covered key demographic and psychosocial information. From a total of 40,333 participants, we collected antenatal EPDS data from 35,374 women and 3144 of these had a score >12 (8.9%). Subsequently, efforts were made to follow-up 22,968 women with a postnatal EPDS. Of 12,361 women who completed postnatal EPDS forms, 925 (7.5%) had an EPDS score >12. Antenatal depression together with a prior history of depression and a low level of partner support were the strongest independent antenatal predictors of a postnatal EPDS score >12. The two main limitations of the study were the use of the EPDS (a self-report screening tool) as the measure of depressive symptoms rather than a clinical diagnosis, and the rate of attrition between antenatal screening and the collection of postnatal follow-up data. Antenatal depressive symptoms appear to be as common as postnatal depressive symptoms. Previous depression, current depression/anxiety, and low partner support are found to be key antenatal risk factors for postnatal depression in this large prospective cohort, consistent with existing meta-analytic surveys. Current depression/anxiety (and to some extent social support) may be amenable to change and can therefore be targeted for intervention.
Matijasevich, Alicia; Munhoz, Tiago N; Tavares, Beatriz Franck; Barbosa, Ana Paula Pereira Neto; da Silva, Diego Mello; Abitante, Morgana Sonza; Dall'Agnol, Tatiane Abreu; Santos, Iná S
2014-10-08
Standardized questionnaires designed for the identification of depression are useful for monitoring individual as well as population mental health. The Edinburgh Postnatal Depression Scale (EPDS) has originally been developed to assist primary care health professionals to detect postnatal depression, but several authors recommend its use outside of the postpartum period. In Brazil, the use of the EPDS for screening depression outside the postpartum period and among non-selected populations has not been validated. The present study aimed to assess the validity of the EPDS as a screening instrument for major depressive episode (MDE) among adults from the general population. This is a validation study that used a population-based sampling technique to select the participants. The study was conducted in the city of Pelotas, Brazil. Households were randomly selected by two stage conglomerates with probability proportional to size. EPDS was administered to 447 adults (≥20 years). Approximately 17 days later, participants were reinterviewed by psychiatrics and psychologists using a structured diagnostic interview (Mini International Neuropsychiatric Interview, MINI). We calculated the sensitivity and specificity of each cutoff point of EPDS, and values were plotted as a receiver operator characteristic curve. The best cutoff point for screening depression was ≥8, with 80.0% (64.4 - 90.9%) sensitivity and 87.0% (83.3 - 90.1%) specificity. Among women the best cutoff point was ≥8 too with values of sensitivity and specificity of 84.4% (67.2 - 94.7%) and 81.3% (75.5 - 86.1%), respectively. Among men, the best cutoff point was ≥7 (75% sensitivity and 89% specificity). The EPDS was shown to be suitable for screening MDE among adults in the community.
Lee, Theresa My; Bautista, Dianne; Chen, Helen Y
2016-10-01
Postnatal depression is a major public health problem with clearly established adverse effects in child outcomes. This study examines the 4-year outcomes of a screening and early intervention programme, in relation to improvement in symptoms, functioning and health quality of life. Women were prospectively recruited up to 6 months postdelivery, using the Edinburgh Postnatal Depression Scale (EPDS) as a screening tool. High-scorers (EPDS >13), were offered psychiatric consultation, and those with borderline scores (EPDS 10-12) were provided counselling, and offered follow-up phone counselling by the assigned case manager. Outcome measures were obtained at baseline, and at 6 months or discharge if earlier, for levels of symptoms, functioning, and health quality of life. From 2008 to 2012, 5245 women were screened, with 307 (5.9%) women with EPDS >13 receiving intervention. Of these, 70.0% had depression, 4.6% anxiety and 3.4% psychosis. In the depression subgroup, the net change was improvement of 93.4% EPDS symptom scores, 92.2% Global Assessment of Functioning (GAF) scores, and 88.3% visual analogue scale (EQ VAS) health quality of life scores. Outcome scores across diagnostic categories demonstrated median changes of 10 points on EPDS, 20 points on GAF, and 25 points on EQ VAS, reflecting 73.9%, 36.4% and 41.7% change from baseline scores. Women with psychosis showed the biggest (80.0%) relative change in GAF functioning scores from baseline to discharge but had the lowest median change in EPDS symptom scores. A screening and intervention programme rightly-sited within an obstetric setting can improve clinical outcomes because of early detection and intervention.
Electrophoretic nanotechnology of composite electrodes for electrochemical supercapacitors.
Su, Y; Zhitomirsky, I
2013-02-14
The electrophoretic deposition (EPD) method has been developed for the fabrication of MnO(2)-multiwalled carbon nanotube (MWCNT) films for application in electrochemical supercapacitors (ESs). For MWCNT applications, which depend on electrical conductivity, it is challenging to achieve dispersion and EPD of pristine MWCNT and avoid defects due to chemical treatment or functionalization. An important finding was the possibility of efficient dispersion and controlled EPD of MWCNT using calconcarboxylic acid (CCA). Moreover, the use of CCA allowed efficient dispersion of MnO(2) in concentrated suspensions and EPD of MnO(2) films. The comparison of the experimental data for chromotrope FB (CFB) and CCA and chemical structures of the molecules provided insight into the mechanism of CCA adsorption on MnO(2). The fabrication of stable suspensions of MnO(2) nanoparticles containing MWCNT, and controlled codeposition of both materials is a crucial aspect in the EPD of composites. The new approach was based on the use of CCA as a charging and dispersing agent for EPD of MnO(2) nanoparticles and MWCNT. The deposition yield measurements at various experimental conditions and Fourier transform infrared spectroscopy data, coupled with results of electron microscopy, thermogravimetric, and differential thermal analysis provided evidence of the formation of MnO(2)-MWCNT composites. The electrochemical testing results and impedance spectroscopy data showed good capacitive behavior of the composite films and the beneficial effect of MWCNTs.
Shakespeare, Judy; Blake, Fiona; Garcia, Jo
2003-01-01
BACKGROUND: Screening for postnatal depression using the Edinburgh Postnatal Depression Scale (EPDS) has been widely recommended and implemented in primary care, although little is known about how acceptable it is to women. AIM: To explore the acceptability to women of postnatal screening by health visitors with the EPDS. DESIGN OF STUDY: Qualitative interview study. SETTING: Postnatal patients from 22 general practices within the area of Oxford City Primary Care Group. METHOD: Thirty-nine postnatal women from a purposive sample were interviewed, chosen on the basis of different general practices, EPDS results at eight weeks and eight months postnatal, and whether 'listening visits' were received. The interviews were analysed using the constant comparative method. RESULTS: Just over half of the women interviewed found screening with the EPDS less than acceptable, whatever their postnatal emotional health. The main themes identified were problems with the process of screening and, in particular, the venue, the personal intrusion of screening and stigma. The women interviewed had a clear preference for talking about how they felt, rather than filling out a questionnaire. CONCLUSION: For this sample, routine screening with the EPDS was less than acceptable for the majority of women. This is of concern, as universal screening with the EPDS for the detection of postnatal depression is already recommended and widespread in primary care. PMID:14601337
Zhong, Qiuyue; Gelaye, Bizu; Rondon, Marta; Sánchez, Sixto E; García, Pedro J; Sánchez, Elena; Barrios, Yasmin V; Simon, Gregory E.; Henderson, David C.; Cripe, Swee May; Williams, Michelle A
2014-01-01
Objective We sought to evaluate the psychometric properties of two widely used screening scales: the Patient Health Questionnaire (PHQ-9) and Edinburgh Postnatal Depression Scale (EPDS) among pregnant Peruvian women. Methods This cross-sectional study included 1,517 women receiving prenatal care from February 2012 to March 2013. A structured interview was used to collect data using PHQ-9 and EPDS. We examined reliability, construct and concurrent validity between two scales using internal consistency indices, factor structures, correlations, and Cohen’s kappa. Results Both scales had good internal consistency (Cronbach’s alpha > 0.8). Correlation between PHQ-9 and EPDS scores was fair (rho=0.52). Based on exploratory factor analysis (EFA), both scales yielded a two-factor structure. EFA including all items from PHQ-9 and EPDS yielded four factors, namely, “somatization”, “depression and suicidal ideation”, “anxiety and depression”, and “anhedonia”. The agreement between the two scales was generally fair at different cutoff scores with the highest Cohen’s kappa being 0.46. Conclusions Both the PHQ-9 and EPDS are reliable and valid scales for antepartum depression assessment. The PHQ-9 captures somatic symptoms, while EPDS detects depressive symptoms comorbid with anxiety during early pregnancy. Our findings suggest simultaneous administration of both scales may improve identification of antepartum depressive disorders in clinical settings. PMID:24766996
Zhong, Qiuyue; Gelaye, Bizu; Rondon, Marta; Sánchez, Sixto E; García, Pedro J; Sánchez, Elena; Barrios, Yasmin V; Simon, Gregory E; Henderson, David C; Cripe, Swee May; Williams, Michelle A
2014-06-01
We sought to evaluate the psychometric properties of two widely used screening scales: the Patient Health Questionnaire (PHQ-9) and Edinburgh Postnatal Depression Scale (EPDS) among pregnant Peruvian women. This cross-sectional study included 1517 women receiving prenatal care from February 2012 to March 2013. A structured interview was used to collect data using PHQ-9 and EPDS. We examined reliability, construct and concurrent validity between two scales using internal consistency indices, factor structures, correlations, and Cohen׳s kappa. Both scales had good internal consistency (Cronbach׳s alpha>0.8). Correlation between PHQ-9 and EPDS scores was fair (rho=0.52). Based on exploratory factor analysis (EFA), both scales yielded a two-factor structure. EFA including all items from PHQ-9 and EPDS yielded four factors, namely, "somatization", "depression and suicidal ideation", "anxiety and depression", and "anhedonia". The agreement between the two scales was generally fair at different cutoff scores with the highest Cohen׳s kappa being 0.46. Both the PHQ-9 and EPDS are reliable and valid scales for antepartum depression assessment. The PHQ-9 captures somatic symptoms, while EPDS detects depressive symptoms comorbid with anxiety during early pregnancy. Our findings suggest simultaneous administration of both scales may improve identification of antepartum depressive disorders in clinical settings. Copyright © 2014 Elsevier B.V. All rights reserved.
Martin, Colin R; Redshaw, Maggie
2018-06-01
The 10-item Edinburgh Postnatal Depression Scale (EPDS) is an established screening tool for postnatal depression. Inconsistent findings in factor structure and replication difficulties have limited the scope of development of the measure as a multi-dimensional tool. The current investigation sought to robustly determine the underlying factor structure of the EPDS and the replicability and stability of the most plausible model identified. A between-subjects design was used. EPDS data were collected postpartum from two independent cohorts using identical data capture methods. Datasets were examined with confirmatory factor analysis, model invariance testing and systematic evaluation of relational and internal aspects of the measure. Participants were two samples of postpartum women in England assessed at three months (n = 245) and six months (n = 217). The findings showed a three-factor seven-item model of the EPDS offered an excellent fit to the data, and was observed to be replicable in both datasets and invariant as a function of time point of assessment. Some EPDS sub-scale scores were significantly higher at six months. The EPDS is multi-dimensional and a robust measurement model comprises three factors that are replicable. The potential utility of the sub-scale components identified requires further research to identify a role in contemporary screening practice. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 1
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware, and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. The IOA product for the RCS analysis consisted of 208 hardware and 2064 EPD and C failure mode worksheets that resulted in 141 hardware and 449 EPD and C potential critical items (PCIs) being identified. A comparison was made of the IOA product to the NASA FMEA/CIL baseline. After comparison and discussions with the NASA subsystem manager, 96 hardware issues, 83 of which concern CIL items or PCIs, and 280 EPD and C issues, 158 of which concern CIL items or PCIs, and 280 EPD and C issues, 158 of which concern CIL items or PCIs, remain unresolved. Volume 1 contains the subsystem description, assessment results, and some of the IOA worksheets.
Enhanced field emission properties of carbon nanotube bundles confined in SiO2 pits
NASA Astrophysics Data System (ADS)
Lim, Yu Dian; Grapov, Dmitry; Hu, Liangxing; Kong, Qinyu; Tay, Beng Kang; Labunov, Vladimir; Miao, Jianmin; Coquet, Philippe; Aditya, Sheel
2018-02-01
It has been widely reported that carbon nanotubes (CNTs) exhibit superior field emission (FE) properties due to their high aspect ratios and unique structural properties. Among the various types of CNTs, random growth CNTs exhibit promising FE properties due to their reduced inter-tube screening effect. However, growing random growth CNTs on individual catalyst islands often results in spread out CNT bundles, which reduces overall field enhancement. In this study, significant improvement in FE properties in CNT bundles is demonstrated by confining them in microfabricated SiO2 pits. Growing CNT bundles in narrow (0.5 μm diameter and 2 μm height) SiO2 pits achieves FE current density of 1-1.4 A cm-2, which is much higher than for freestanding CNT bundles (76.9 mA cm-2). From the Fowler Nordheim plots, confined CNT bundles show a higher field enhancement factor. This improvement can be attributed to the reduced bundle diameter by SiO2 pit confinement, which yields bundles with higher aspect ratios. Combining the obtained outcomes, it can be conclusively summarized that confining CNTs in SiO2 pits yields higher FE current density due to the higher field enhancement of confined CNTs.
Self-assembled pit arrays as templates for the integration of Au nanocrystals in oxide surfaces.
Konstantinović, Z; Sandiumenge, F; Santiso, J; Balcells, Ll; Martínez, B
2013-02-07
We report on the fabrication of long-range ordered arrays of Au nanocrystals (sub-50 nm range) on top of manganite (La(2/3)Sr(1/3)MnO(3)) thin films achieving area densities around 2 × 10(10) gold nanocrystals per cm(2), well above the densities achievable by using conventional nanofabrication techniques. The gold-manganite interface exhibits excellent conduction properties. Long-range order is achieved by a guided self-assembling process of Au nanocrystals on self-organized pit-arrays acting as a template for the nucleation of gold nanocrystals. Self-organization of pits on the manganite film surface promoted by the underlying stepped SrTiO(3) substrate is achieved by a fine tuning of the growth kinetic pathway, taking advantage of the unusual misfit strain relaxation behaviour of manganite films.
Characterization of HgCdTe and Related Materials For Third Generation Infrared Detectors
NASA Astrophysics Data System (ADS)
Vaghayenegar, Majid
Hg1-xCdxTe (MCT) has historically been the primary material used for infrared detectors. Recently, alternative substrates for MCT growth such as Si, as well as alternative infrared materials such as Hg1-xCdxSe, have been explored. This dissertation involves characterization of Hg-based infrared materials for third generation infrared detectors using a wide range of transmission electron microscopy (TEM) techniques. A microstructural study on HgCdTe/CdTe heterostructures grown by MBE on Si (211) substrates showed a thin ZnTe layer grown between CdTe and Si to mediate the large lattice mismatch of 19.5%. Observations showed large dislocation densities at the CdTe/ZnTe/Si (211) interfaces, which dropped off rapidly away from the interface. Growth of a thin HgTe buffer layer between HgCdTe and CdTe layers seemed to improve the HgCdTe layer quality by blocking some defects. A second study investigated the correlation of etch pits and dislocations in as-grown and thermal-cycle-annealed (TCA) HgCdTe (211) films. For as-grown samples, pits with triangular and fish-eye shapes were associated with Frank partial and perfect dislocations, respectively. Skew pits were determined to have a more complex nature. TCA reduced the etch-pit density by 72%. Although TCA processing eliminated the fish-eye pits, dislocations reappeared in shorter segments in the TCA samples. Large pits were observed in both as-grown and TCA samples, but the nature of any defects associated with these pits in the as-grown samples is unclear. Microstructural studies of HgCdSe revealed large dislocation density at ZnTe/Si(211) interfaces, which dropped off markedly with ZnTe thickness. Atomic-resolution STEM images showed that the large lattice mismatch at the ZnTe/Si interface was accommodated through {111}-type stacking faults. A detailed analysis showed that the stacking faults were inclined at angles of 19.5 and 90 degrees at both ZnTe/Si and HgCdSe/ZnTe interfaces. These stacking faults were associated with Shockley and Frank partial dislocations, respectively. Initial attempts to delineate individual dislocations by chemical etching revealed that while the etchants successfully attacked defective areas, many defects in close proximity to the pits were unaffected.
Corrosion behavior of binary titanium aluminide intermetallics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saffarian, H.M.; Gan, Q.; Hadkar, R.
1996-08-01
The corrosion behavior of arc-melted binary titanium aluminide intermetallics TiAl, Ti{sub 2}Al, and TiAl{sub 3} in aqueous sodium sulfate and sodium chloride solutions was measured and compared to that of pure Ti and Al. Effects of electrolyte composition (e.g., sulfate [0.25 M SO{sub 4}{sup 2}{sup {minus}}], chloride [0.1 to 1.0 M Cl{sup {minus}}], and pH [3 to 10]) were examined. Anodic polarization of titanium aluminides in aqueous SO{sub 4}{sup 2}{sup {minus}} solutions was similar (showing passive behavior), but no pitting or pitting potential (E{sub pit}) was observed. In aqueous NaCl, however, titanium aluminides were susceptible to pitting, and E{sub pit}more » decreased with increasing Al content (i.e., Ti{sub 3}Al had the highest E{sub pit} and, therefore, a greater resistance to pitting, followed by TiAl and TiAl{sub 3}). For TiAl, E{sub pit} was slightly dependent upon pH or Cl{sup {minus}} concentration. Pit morphology and E{sub pit} values were quite different for TiAl compared to Ti{sub 3}Al. TiAl showed numerous small pits, whereas Ti{sub 3}Al exhibited fewer but larger and deeper pits. The larger pit density for TiAl was associated with Al-rich interdendrite regions. One interesting feature of the anodic polarization curves for Ti{sub 3}Al was a small anodic peak frequently observed at {approximately}1.4 V{sub SCE} to 1.8 V{sub SCE}. Results suggested this peak was associated with pit initiation, since pitting initiated concurrently with the peak or immediately afterward.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quan, Zhijue, E-mail: quanzhijue@ncu.edu.cn; Wang, Li, E-mail: wl@ncu.edu.cn; Zheng, Changda
2014-11-14
The roles of V-shaped pits on the improvement of quantum efficiency in InGaN/GaN multiple quantum well (MQW) light-emitting diodes are investigated by numerical simulation. The simulation results show that V-shaped pits cannot only screen dislocations, but also play an important role on promoting hole injection into the MQWs. It is revealed that the injection of holes into the MQW via the sidewalls of the V-shaped pits is easier than via the flat region, due to the lower polarization charge densities in the sidewall structure with lower In concentration and (10–11)-oriented semi-polar facets.
Direct current electrical potential measurement of the growth of small cracks
NASA Technical Reports Server (NTRS)
Gangloff, Richard P.; Slavik, Donald C.; Piascik, Robert S.; Van Stone, Robert H.
1992-01-01
The analytical and experimental aspects of the direct-current electrical potential difference (dcEPD) method for continuous monitoring of the growth kinetics of short (50 to 500 microns) fatigue cracks are reviewed, and successful applications of the deEPD method to study fatigue crack propagation in a variety of metallic alloys exposed to various environments are described. Particular attention is given to the principle of the dcEPD method, the analytical electrical potential calibration relationships, and the experimental procedures and equipment.
NASA Astrophysics Data System (ADS)
Fleetwood, James D.
Solid oxide fuel cells (SOFCs) are a promising element of comprehensive energy policies due to their direct mechanism for converting the oxidization of fuel, such as hydrogen, into electrical energy. Both very low pressure plasma spray and electrophoretic deposition allow working with high melting temperature SOFC suspension based feedstock on complex surfaces, such as in non-planar SOFC designs. Dense, thin electrolytes of ideal composition for SOFCs can be fabricated with each of these processes, while compositional control is achieved with dissolved dopant compounds that are incorporated into the coating during deposition. In the work reported, sub-micron 8 mole % Y2O3-ZrO2 (YSZ) and gadolinia-doped ceria (GDC), powders, including those in suspension with scandium-nitrate dopants, were deposited on NiO-YSZ anodes, via very low pressure suspension plasma spray (VLPSPS) at Sandia National Laboratories' Thermal Spray Research Laboratory and electrophoretic deposition (EPD) at Purdue University. Plasma spray was carried out in a chamber held at 320 - 1300 Pa, with the plasma composed of argon, hydrogen, and helium. EPD was characterized utilizing constant current deposition at 10 mm electrode separation, with deposits sintered from 1300 -- 1500 °C for 2 hours. The role of suspension constituents in EPD was analyzed based on a parametric study of powder loading, powder specific surface area, polyvinyl butyral (PVB) content, polyethyleneimine (PEI) content, and acetic acid content. Increasing PVB content and reduction of particle specific surface area were found to eliminate the formation of cracks when drying. PEI and acetic acid content were used to control suspension stability and the adhesion of deposits. Additionally, EPD was used to fabricate YSZ/GDC bilayer electrolyte systems. The resultant YSZ electrolytes were 2-27 microns thick and up to 97% dense. Electrolyte performance as part of a SOFC system with screen printed LSCF cathodes was evaluated with peak power densities as high as 520 mW/cm2 at 800 °C for YSZ and 350 mW/cm 2 at 800 °C for YSZ/GDC bilayer electrolytes.
Study of Etching Pits in a Large-grain Single Cell Bulk Niobium Cavity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Xin; Ciovati, Gianluigi; Reece, Charles E.
2009-11-01
Performance of SRF cavities are limited by non-linear localized effects. The variation of local material characters between "hot" and "cold" spots is thus of intense interest. Such locations were identified in a BCP-etched large-grain single-cell cavity and removed for examination by high resolution electron microscopy (SEM), electron-back scattering diffraction microscopy (EBSD), optical microscopy, and 3D profilometry. Pits with clearly discernable crystal facets were observed in both "hotspot" and "coldspot" specimens. The pits were found in-grain, at bi-crystal boundaries, and on tri-crystal junctions. They are interpreted as etch pits induced by surface crystal defects (e.g. dislocations). All "coldspots" examined had qualitativelymore » low density of etching pits or very shallow tri-crystal boundary junction. EBSD revealed crystal structure surrounding the pits via crystal phase orientation mapping, while 3D profilometry gave information on the depth and size of the pits. In addition, a survey of the samples by energy dispersive X-ray analysis (EDX) did not show any significant contamination of the samples surface.« less
NASA Astrophysics Data System (ADS)
Hughes, D.; Zoughi, R.; Austin, R.; Wood, N.; Engelbart, R.
2003-03-01
Detection of corrosion precursor pitting on metallic surfaces under various coatings and on bare metal is of keen interest in evaluation of aircraft fuselage. Near-field microwave nondestructive testing methods, utilizing open-ended rectangular waveguides and coaxial probes, have been used extensively for detection of surface flaws in metals, both on bare metal and under a dielectric coating. This paper presents the preliminary results of using microwave techniques to detect corrosion precursor pitting under paint and primer, applique and on bare metal. Machined pits of 500 μm diameter were detected using open-ended rectangular waveguides at V-Band under paint and primer and applique, and on bare metal. Using coaxial probes, machined pits with diameters down to 150 μm on bare metal were also detected. Relative pit size and density were shown on a corrosion-pitted sample using open-ended rectangular waveguides at frequencies of 35 GHz to 70 GHz. The use of Boeing's MAUS™ scanning systems provided improved results by alleviating standoff variation and scanning artifact. Typical results of this investigation are also presented.
Anadromous sea lampreys (Petromyzon marinus) are ecosystem engineers in a spawning tributary
Hogg, Robert S.; Coghlan, Stephen M.; Zydlewski, Joseph D.; Simon, Kevin S.
2014-01-01
Sea lampreys (Petromyzon marinus) disturb the substratum during nest construction and alter the physical habitat, potentially affecting other stream organisms. We quantified differences in depth, velocity, fine-sediment coverage, embeddedness, intragravel permeability and benthic invertebrate assemblages (density and diversity) among nest mounds, nest pits and undisturbed reference locations over a 4-month period after June spawning. In 2010 and 2011, immediate and persistent effects of nest construction were assessed in summer (July) and in autumn (late September to early October), respectively. Randomly selected nests were sampled annually (25 each in summer and autumn). Nest construction increased stream-bed complexity by creating and juxtaposing shallow, swift, rocky habitat patches with deep, slow, sandy habitat patches. Mounds had a 50–143% less cover of fine sediment, and a 30–62% reduction in embeddedness, compared to pits and reference locations. These physical changes persisted into the autumn (almost 4 months). Five insect families contributed 74% of the benthic invertebrate abundance: Chironomidae (27%), Hydropsychidae (26%), Heptageniidae (8%), Philopotamidae (7%) and Ephemerellidae (6%). Densities of Hydropsychidae, Philopotamidae and Heptageniidae were up to 10 times greater in mounds than in pits and adjacent reference habitat. In summer, mounds had twice the density of Chironomidae than did pits, and 1.5 times more than reference habitats, but densities were similar among the habitats in autumn. These results suggest that spawning sea lampreys are ecosystem engineers. The physical disturbance caused by nest-building activity was significant and persistent, increasing habitat heterogeneity and favouring pollution-sensitive benthic invertebrates and, possibly, drift-feeding fish.
Alvarado-Esquivel, Cosme; Sifuentes-Alvarez, Antonio; Salas-Martinez, Carlos
2014-01-01
:Depression may occur in teenager pregnant women. The use of a validated tool for screening depression is highly recommended. The Edinburgh postnatal depression scale (EPDS) is a screening tool for depression used in women during the postnatal period and pregnancy. However, the EPDS has not been validated in teenager pregnant women. Therefore, we sought to validate a Spanish translated Mexican version of the EPDS in a population of teenager pregnant women. One hundred and twenty teenager pregnant women attending routine prenatal consultations in a public hospital in Durango City, Mexico participated in the study. All participants submitted a revised Spanish translated Mexican version of the EPDS and were examined by a psychiatrist to evaluate the presence of depression by using DSM-IV criteria. Of the 120 teenager pregnant women studied, 2 had major depression and 25 had minor depression according to the DSM-IV criteria. The optimal EPDS cut-off for screening combined major and minor depression in teenager pregnant women was 8/9. At this threshold, we found a sensitivity of 70.4%, a specificity of 84.9%, a positive predictive value of 47.6%, a negative predictive value of 91.0%, and an area under the curve of 0.81 (95% confidence interval: 0.56-1.07). The EPDS can be used for screening depression in Mexican teenager pregnant women whenever a cut-off score of 8/9 is used.
Alvarado-Esquivel, Cosme; Sifuentes-Alvarez, Antonio; Salas-Martinez, Carlos
2014-01-01
Background :Depression may occur in teenager pregnant women. The use of a validated tool for screening depression is highly recommended. The Edinburgh postnatal depression scale (EPDS) is a screening tool for depression used in women during the postnatal period and pregnancy. However, the EPDS has not been validated in teenager pregnant women. Therefore, we sought to validate a Spanish translated Mexican version of the EPDS in a population of teenager pregnant women. Methods: One hundred and twenty teenager pregnant women attending routine prenatal consultations in a public hospital in Durango City, Mexico participated in the study. All participants submitted a revised Spanish translated Mexican version of the EPDS and were examined by a psychiatrist to evaluate the presence of depression by using DSM-IV criteria. Results: Of the 120 teenager pregnant women studied, 2 had major depression and 25 had minor depression according to the DSM-IV criteria. The optimal EPDS cut-off for screening combined major and minor depression in teenager pregnant women was 8/9. At this threshold, we found a sensitivity of 70.4%, a specificity of 84.9%, a positive predictive value of 47.6%, a negative predictive value of 91.0%, and an area under the curve of 0.81 (95% confidence interval: 0.56-1.07). Conclusion: The EPDS can be used for screening depression in Mexican teenager pregnant women whenever a cut-off score of 8/9 is used. PMID:25493092
Ward, Thomas J; Piechowiak, Rachel L; Patel, Rahul S; Fischman, Aaron M; Nowakowski, F Scott; Kim, Edward; Ellozy, Sharif H; Faries, Peter L; Lookstein, Robert A
2014-10-01
To examine the safety and efficacy of the SpiderFX embolic protection device (EPD) in the below-the-knee (BTK) circulation in patients with critical limb ischemia (CLI). A single-center retrospective review was performed to identify patients with CLI and single-vessel runoff in whom the SpiderFX EPD was used in the BTK circulation. Technical success and device-related complications were the primary endpoints. Retrieval of macroscopic debris in the EPD, 1-year freedom from major adverse limb events (MALEs), and 30-day perioperative death were also evaluated. A major amputation, surgical bypass, endovascular thrombectomy, or endovascular thrombolysis was considered a MALE. Thirty-six patients (21 men; mean age, 75.8 y) treated between 2008 and 2013 had endovascular revascularization with use of the SpiderFX EPD in the BTK circulation. The SpiderFX EPD was successfully deployed in all cases; the technical success rate of revascularization was 100%. Two minor and zero major complications were observed related to the SpiderFX. Two MALEs, a major amputation and a subsequent surgical bypass, were observed in the cohort. All MALEs occurred within 1 year of treatment (1-y freedom from MALE rate, 90%). Debris was retrieved in the SpiderFX device in 47% of patients. The use of the SpiderFX EPD in the BTK circulation in patients with CLI is safe and frequently retrieves debris. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.
Zanardo, Vincenzo; Giliberti, Lara; Volpe, Francesca; Parotto, Matteo; de Luca, Federico; Straface, Gianluca
2017-06-01
To investigate the applicability of the Edinburgh Postnatal Depression Scale (EPDS) for identifying depressive symptoms following vaginal or cesarean delivery. The present observational study included consecutive Italian-speaking women who underwent vaginal or cesarean deliveries of uncomplicated singleton pregnancies at term at Policlinico Abano Terme, Abano Terme, Italy, between February 1, 2014, and May 31, 2015, who completed the EPDS 2 days after delivery. EPDS scores and the depression, anxiety, and anhedonia subscale items were compared between delivery methods to identify factors predictive of high EPDS scores. There were 950 patients included in the analysis; 694 (73.1%) and 256 (26.9%) patients underwent vaginal and cesarean deliveries, respectively. Total EPDS scores were higher among patients who had cesarean deliveries compared with vaginal deliveries (6.95±4.80 vs 6.05±4.20; P=0.007); the depression (0.53±0.72 vs 0.37±0.65; P=0.007), anxiety (1.07±0.88 vs 1.16±0.93; P=0.021), and anhedonia (0.32±0.59 vs 0.19±0.48; P=0.009) subscale scores were all higher among patients who underwent cesarean deliveries. Women who underwent cesarean deliveries demonstrated higher EPDS scores and could be at increased risk of developing early postpartum depressive symptomatology, particularly anhedonia, anxiety, and depression. © 2017 International Federation of Gynecology and Obstetrics.
Agampodi, Suneth Buddhika; Agampodi, Thilini Chanchala
2013-01-01
Mental health problems among women of reproductive age group contribute to 7% of Global Burden of Diseases of women of all ages. Purpose of this study was to determine the prevalence and correlates of antenatal depression among pregnant women in Anuradhapura, Sri Lanka, and to explore the factor structure of EPDS. Pregnant women with gestational age of 24-36 weeks and residing in Anuradhapura district, Sri Lanka were recruited to the study using a two stage cluster sampling procedure. Sinhalese version of Edinburgh Post Partum Depression Scale (EPDS) and an interviewer administered questionnaire was use to collect data. A cut off value of 9 was used for the Sinhalese version of EPDS. A total of 376 pregnant women were studied. Median EPDS score among pregnant women was 5 (IQR 2-8). Prevalence of antenatal depression in this study sample was 16.2% (n = 61). Thought of self harming (item number 10) was reported by 26 pregnant women (6.9%). None of the socio-demographic factors were associated with depression in this study sample. Having heart burn was significantly associated with depressive symptoms (p = 0.041). Sri Lankan version of EPDS showed a two factor solution. Anxiety was not emerged as a separate factor in this analysis. Prevalence of antenatal depression in Anuradhapura, Sri Lanka was relatively low. Anxiety was not emerged as a separate factor in the Sinhalese version of the EPDS.
The semantic component of the evoked potential of differentiation.
Izmailov, Chingis A; Korshunova, Svetlana G; Sokolov, Yevgeniy N
2008-05-01
This work analyzes data from recordings of (occipital and temporal) cortical evoked potentials (called evoked potentials of differentiation (EPD) occurring in humans in response to an abrupt substitution of stimuli. As stimuli we used three groups of words: the names of the ten basic colors taken from Newton's color circle; the names of seven basic emotions forming Shlossberg's circle of emotions; and seven nonsense words comprised of random combinations of letters. Within each group of word stimuli we constructed a matrix of the differences between the amplitudes of mid-latency components of EPD for each pair of words. This matrix was analyzed using the method of multidimensional scaling. As a result of this analysis we were able to distinguish the semantic and configurational components of EPD amplitude. The semantic component of EPD amplitude was evaluated by comparing structure of the data obtained to the circular structures of emotion and color names. The configurational component was evaluated on the basis of the attribute of word length (number of letters). It was demonstrated that the semantic component of the EPD can only be detected in the left occipital lead at an interpeak amplitude of P120-N180. The configurational component is reflected in the occipital and temporal leads to an identical extent, but only in the amplitude of a later (N180-P230) component of the EPD. The results obtained are discussed in terms of the coding of categorized, configurational, and semantic attributes of a visual stimulus.
NASA Astrophysics Data System (ADS)
Wang, Xinhua; Liu, Qiang; Chun, Yingchun; Li, Yingchao; Wang, Zuquan
2018-04-01
The delamination of epoxy coating on X80 pipeline steel was evaluated under various stray alternating current (AC) interferences (0-300 A/m2). Qualitative and quantitative analyses were carried out using scanning electrochemical microscopy (SECM), electrochemical impedance spectroscopy (EIS), and three-dimensional digital microscopy. The results show that the SECM current is directly proportional to the soaking time and applied current density. The variation in SECM current curve shape indicates the delamination distance of epoxy coatings at the defect area. The depths of corrosion pits at 50, 100, and 300 A/m2 stray currents were 140, 160, and 240 μm, respectively. The corrosion pits also became wider with increasing current densities. With increasing stray AC densities, both the coating delamination and pit depth became more severe at the same soaking time. The EIS results show that the change in impedance was not significant without stray current, whereas the impedance first decreased and then increased when stray current was applied. These results are consistent with the SECM measurements.
Small, Rhonda; Lumley, Judith; Yelland, Jane; Brown, Stephanie
2007-01-01
The Edinburgh Postnatal Depression Scale (EPDS) has been widely used to assess maternal depression following childbirth in a range of English speaking countries, and increasingly also in translation in non-English speaking ones. It has performed satisfactorily in most validation studies, has proved easy to administer, is acceptable to women, and rates of depression in the range of 10-20% have been consistently found. The performance of the EPDS was compared across different population samples in Australia: (i) Women born in Australia or in another English speaking country who completed the EPDS in English as part of the 1994 postal Survey of Recent Mothers (SRM) 6-7 months after birth (n = 1166); (ii) Women born in non-English speaking countries who also completed the EPDS in English in the same survey (n = 142); and (iii) Women born in Vietnam (n = 103), Turkey (n = 104) and the Philippines (n = 106) who completed the EPDS 6-9 months after birth in translation in the Mothers in a New Country Study (MINC) study (total n = 313). The pattern of item responses on the EPDS was assessed in various ways across the samples and internal reliability coefficients were calculated. Exploratory factor analyses were also conducted to assess the similarity in the factor solutions across the samples. The EPDS had good construct validity and item endorsement by women was similar across the samples. Internal reliability of the scale was also very satisfactory with Cronbach's alpha for each sample being > or = 8. Between 39 and 46% of the variance in each of the three main samples was accounted for by one principal factor 'depression' (6-7 items loading), with two supplementary factors 'loss of enjoyment' (2 items loading) and 'despair/self-harm' (2-3 items loading) accounting for a further 20-25% of the variance. Alternative one and two factor solutions also showed a great deal of consistency between the samples. The good item consistency of the EPDS and the relative stability of the factor patterns across the samples are indicative that the scale is understood and completed in similar ways by women in these different English speaking and non-English speaking population groups. With the proviso that careful translation processes and extensive piloting of translations are always needed, these findings lend further support to the use of the EPDS in cross-cultural research on depression following childbirth.
Astarita, C; Scala, G; Sproviero, S; Franzese, A
1996-01-01
Several controlled clinical trials have shown that specific immunotherapy (SIT) using incremental injections of allergens can be effective in the treatment of allergic rhinitis and asthma. Nevertheless, the risk of side effects have led to some recommended limitations of SIT. Enzyme-potentiated desensitization (EPD) is a proposed method for immunotherapy with very low doses of mixed allergens plus beta-glucuronidase enzyme, for which irrelevant or no side effects have been claimed. The aim of this study was to determine the clinical efficacy of EPD in the treatment of pollinosis. A double-blind placebo-controlled trial of EPD among 20 patients sensitive to Parietaria and grass pollen was performed. All patients recorded daily symptom scores for nine months following a single intradermal injection of EPD or buffered saline received in February. Symptoms recorded were nasal itching and obstruction, sneezing, rhinorrhea, itchy eyes and excessive tear production. Moreover, total and specific lgE were measured and CD3+, CD4+ and CD8+ peripheral blood lymphocytes were counted at different times. In the same period, ten additional subjects, with an allergic clinical profile similar to the subjects admitted to the double-blind trial, were studied in an open clinical trial in order to evaluate the effects of EPD without enzyme using a mixture of allergens. Symptom scores were higher in the placebo group (p < 0.001), with a similar level of significance for both global symptom score and for each individual symptom. Active-treated patients had a significant post-treatment increase in the mean percentage of T-CD8+ peripheral blood cells and a significant post-seasonal decrease in the mean percentage of Parietaria specific lgE. On the contrary, placebo-treated patients had a borderline significant post-seasonal decrease in the mean percentage of CD8+ circulating cells and a significant seasonal increase in the mean percentage of Parietaria specific lgE with no significant post-seasonal decrease. Finally, clinical results of the mixture of allergens injection were similar to those of the placebo in the double-blind trial. EPD injection caused only an asymptomatic, local wheal and flare lasting about two hours. Two patients (20%) in the active-treated group experienced a delayed, mild, unusual headache lasting about two days. In conclusion, EPD is clinically effective in the treatment of pollinosis. Some immunological modifications observed in the EPD-treated patients suggest an EPD-induced enhancement of tolerogenic mechanisms like "immune deviation."
ROSNER, SABINE; KLEIN, ANDREA; MÜLLER, ULRICH; KARLSSON, BO
2011-01-01
Summary Stem segments of eight five-year-old Norway spruce (Picea abies (L.) Karst.) clones differing in growth characteristics were tested for maximum specific hydraulic conductivity (ks100), vulnerability to cavitation and behavior under mechanical stress. The vulnerability of the clones to cavitation was assessed by measuring the applied air pressure required to cause 12 and 50% loss of conductivity (Ψ12, Ψ50) and the percent loss of conductivity at 4 MPa applied air pressure (PLC4MPa). The bending strength and stiffness and the axial compression strength and stiffness of the same stem segments were measured to characterize wood mechanical properties. Growth ring width, wood density, latewood percentage, lumen diameter, cell wall thickness, tracheid length and pit dimensions of earlywood cells, spiral grain and microfibril angles were examined to identify structure–function relationships. High ks100 was strongly and positively related to spiral grain angle, which corresponded positively to tracheid length and pit dimensions. Spiral grain may reduce flow resistance of the bordered pits of the first earlywood tracheids, which are characterized by rounded tips and an equal distribution of pits along the entire length. Wood density was unrelated to hydraulic vulnerability parameters. Traits associated with higher hydraulic vulnerability were long tracheids, high latewood percentage and thick earlywood cell walls. The positive relationship between earlywood cell wall thickness and vulnerability to cavitation suggest that air seeding through the margo of bordered pits may occur in earlywood. There was a positive phenotypic and genotypic relationship between ks100 and PLC4MPa, and both parameters were positively related to tree growth rate. Variability in mechanical properties depended mostly on wood density, but also on the amount of compression wood. Accordingly, hydraulic conductivity and mechanical strength or stiffness showed no tradeoff. PMID:17472942
NASA Astrophysics Data System (ADS)
Madhikar, Pratik Ravindra
The most important and crucial design feature while designing an Aircraft Electric Power Distribution System (EPDS) is reliability. In EPDS, the distribution of power is from top level generators to bottom level loads through various sensors, actuators and rectifiers with the help of AC & DC buses and control switches. As the demands of the consumer is never ending and the safety is utmost important, there is an increase in loads and as a result increase in power management. Therefore, the design of an EPDS should be optimized to have maximum efficiency. This thesis discusses an integrated tool that is based on a Need Based Design method and Fault Tree Analysis (FTA) to achieve the optimum design of an EPDS to provide maximum reliability in terms of continuous connectivity, power management and minimum cost. If an EPDS is formulated as an optimization problem then it can be solved with the help of connectivity, cost and power constraints by using a linear solver to get the desired output of maximum reliability at minimum cost. Furthermore, the thesis also discusses the viability and implementation of the resulted topology on typical large aircraft specifications.
Development of the Kiel sensors for the EPD instrument on-board Solar Orbiter
NASA Astrophysics Data System (ADS)
Martin, Cesar; Wimmer-Schweingruber, Robert F.; Kulkarni, Shrinivasrao R.; Tammen, Jan; Terasa, Christoph; Yu, Jia; Boden, Sebastian; Steinhagen, Jan; Panitzsch, Lauri; Ravanbakhsh, Ali; Boettcher, Stephan; Hamann, Christian; Seimetz, Lars; Rodriguez-Pacheco, Javier
2015-04-01
Solar Orbiter is ESA's next solar and heliospheric mission, planned for launch in January 2017 and approaching the Sun as close as 0.28 AU. One of the Solar Orbiter's scientific questions is "How do the solar eruptions produce energetic particle radiation that fills the heliosphere?". The Energetic Particle Detector (EPD) will provide key measurements for this and the other Solar Orbiter science objectives. The EPD suite consists of four sensors measuring electrons, protons, and ions from helium to iron, and operating at partly overlapping energy ranges from 2 keV/n up to 200 MeV/n. The EPD sensors are: SupraThermal Electrons and Protons(STEP), Suprathermal Ion Spectrograph (SIS), Electron Proton Telescope (EPT) and High Energy Telescope (HET). Besides, the EPD sensors share the Instrument Control Unit (ICU). The University of Kiel in Germany is responsible for developing the EPT-HET, STEP and SIS sensors. Here we present the development status of the EPT-HET and STEP sensors focusing on the activities planned for the current phase C. Those activities include results of the integration and EMC tests on the EPT-HET and STEP Engineering Model (EM) and the assembly of the Proto Qualification Model (PQM).
Development of the Kiel sensors for the EPD instrument on-board Solar Orbiter
NASA Astrophysics Data System (ADS)
Martin, Cesar; Wimmer-Schweingruber, Robert F.; Kulkarni, Shrinivasrao R.; Tammen, Jan; Terasa, Christoph; Yu, Jia; Boden, Sebastian; Steinhagen, Jan; Panitzsch, Lauri; Ravanbakhsh, Ali; Boettcher, Stephan; Hamann, Christian; Seimetz, Lars; Rodriguez-Pacheco, Javier
2014-05-01
Solar Orbiter is ESA's next solar and heliospheric mission, planned for launch in January 2017 and approaching the Sun as close as 0.28 AU. One of the Solar Orbiter's scientific questions is "How do the solar eruptions produce energetic particle radiation that fills the heliosphere?". The Energetic Particle Detector (EPD) will provide key measurements for this and the other Solar Orbiter science objectives. The EPD suite consists of four sensors measuring electrons, protons, and ions from helium to iron, and operating at partly overlapping energy ranges from 2 keV/n up to 200 MeV/n. The EPD sensors are: SupraThermal Electrons and Protons(STEP), Suprathermal Ion Spectrograph (SIS), Electron Proton Telescope (EPT) and High Energy Telescope (HET). Besides, the EPD sensors share the Instrument Control Unit (ICU). The University of Kiel in Germany is responsible for developing the EPT-HET, STEP and SIS sensors. Here we present the development status of the EPT-HET and STEP sensors focusing on the activities planned for the current phase C. Those activities include results of the environmental tests on the EPT-HET Structural Thermal Model (STM) and the assembly of the Engineering Model (EM).
Electrophoretic deposition of biomaterials
Boccaccini, A. R.; Keim, S.; Ma, R.; Li, Y.; Zhitomirsky, I.
2010-01-01
Electrophoretic deposition (EPD) is attracting increasing attention as an effective technique for the processing of biomaterials, specifically bioactive coatings and biomedical nanostructures. The well-known advantages of EPD for the production of a wide range of microstructures and nanostructures as well as unique and complex material combinations are being exploited, starting from well-dispersed suspensions of biomaterials in particulate form (microsized and nanoscale particles, nanotubes, nanoplatelets). EPD of biological entities such as enzymes, bacteria and cells is also being investigated. The review presents a comprehensive summary and discussion of relevant recent work on EPD describing the specific application of the technique in the processing of several biomaterials, focusing on (i) conventional bioactive (inorganic) coatings, e.g. hydroxyapatite or bioactive glass coatings on orthopaedic implants, and (ii) biomedical nanostructures, including biopolymer–ceramic nanocomposites, carbon nanotube coatings, tissue engineering scaffolds, deposition of proteins and other biological entities for sensors and advanced functional coatings. It is the intention to inform the reader on how EPD has become an important tool in advanced biomaterials processing, as a convenient alternative to conventional methods, and to present the potential of the technique to manipulate and control the deposition of a range of nanomaterials of interest in the biomedical and biotechnology fields. PMID:20504802
Iliadis, S I; Comasco, E; Hellgren, C; Kollia, N; Sundström Poromaa, I; Skalkidou, A
2017-01-01
This study examined the association between a single nucleotide polymorphism in the hydroxysteroid (11-beta) dehydrogenase 1 gene and neuroticism, as well as the possible mediatory role of neuroticism in the association between the polymorphism and postpartum depressive symptoms. 769 women received questionnaires containing the Edinburgh Postnatal Depression Scale (EPDS) at six weeks postpartum and demographic data at pregnancy week 17 and 32 and at six weeks postpartum, as well as the Swedish universities Scales of Personality at pregnancy week 32. Linear regression models showed an association between the GG genotype and depressive symptoms. When neuroticism was introduced in the model, it was associated with EPDS score, whereas the association between the GG genotype and EPDS became borderline significant. A path analysis showed that neuroticism had a mediatory role in the association between the polymorphism and EPDS score. The use of the EPDS, which is a self-reporting instrument. Neuroticism was associated with the polymorphism and had a mediatory role in the association between the polymorphism and postpartum depression. This finding elucidates the genetic background of neuroticism and postpartum depression. Copyright © 2016 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Haufler, W. A.; Marino, A. J.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Orbital Maneuvering System (OMS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter OMS hardware. The IOA analysis defined the OMS as being comprised of the following subsystems: helium pressurization, propellant storage and distribution, Orbital Maneuvering Engine, and EPD and C. The IOA product for the OMS analysis consisted of 284 hardware and 667 EPD and C failure mode worksheets that resulted in 160 hardware and 216 EPD and C potential critical items (PCIs) being identified. A comparison was made of the IOA product to the NASA FMEA/CIL baseline which consisted of 101 hardware and 142 EPD and C CIL items.
Superconducting MgB2 wires with vanadium diffusion barrier
NASA Astrophysics Data System (ADS)
Hušek, I.; Kováč, P.; Melišek, T.; Kulich, M.; Rosová, A.; Kopera, L.; Szundiová, B.
2017-10-01
Single-core MgB2 wires with a vanadium barrier and Cu stabilization have been made by the in situ powder-in-tube (PIT) and internal magnesium diffusion (IMD) into boron processes. Heat treatment of PIT wires was done at the temperature range of 650 °C-850 °C/30 min. Critical currents of differently treated MgB2/V/Cu wires have been measured and related with the structure of MgB2. It was found that critical current density of MgB2/V wire annealed above 700 °C decreases rapidly. The obtained results clearly show that vanadium is a well formable metal and can be applied as an effective diffusion barrier for MgB2 wires heat-treated at temperatures ≤700 °C. This temperature limit is well applicable for MgB2 wires with high current densities made by PIT and also by the IMD process.
Peng, Wei; de Bruijn, Henriette S; Farrell, Eric; Sioud, Mouldy; Mashayekhi, Vida; Oliveira, Sabrina; van Dam, Go M; Roodenburg, Jan L N; Witjes, Max J H; Robinson, Dominic J
2018-05-19
The aim of this study was to investigate the effects of targeted photoimmunotherapy (PIT) in vitro on cell lines with various expression levels of epidermal growth factor receptor (EGFR) using an anti-EGFR targeted conjugate composed of Cetuximab and IR700DX, phthalocyanine dye. Relative EGFR density and cell binding assay was conducted in three human head & neck cancer cell lines (scc-U2, scc-U8, and OSC19) and one reference cell line A431. After incubation with the conjugate for 1 or 24 hours, cellular uptake and localization were investigated by confocal laser scanning microscopy and quantified by image analysis. Cell survival was determined using the MTS assay and alamarBlue assay after PIT with a 690 nm laser to a dose of 7 J.cm -2 (at 5 mW.cm -2 ). The mode of cell death was examined with flow cytometry using apoptosis/necrosis staining by Annexin V/propidium iodide, together with immunoblots of anti-apoptotic Bcl-2 family proteins Bcl-2 and Bcl-xL. A431 cells had the highest EGFR density followed by OSC19, and then scc-U2 and scc-U8. The conjugates were localized both on the surface and in the cytosol of the cells after 1- and 24-hour incubation. After 24-hour incubation the granular pattern was more pronounced and in a similar pattern of a lysosomal probe, suggesting that the uptake of conjugates by cells was via receptor-mediated endocytosis. The results obtained from the quantitative imaging analysis correlate with the level of EGFR expression. Targeted PIT killed scc-U8 and A431 cells efficiently; while scc-U2 and OSC19 were less sensitive to this treatment, despite having similar EGFR density, uptake and localization pattern. Scc-U2 cells showed less apoptotic cell dealth than in A431 after 24-hour targeted PIT. Immunoblots showed significantly higher expression of anti-apoptotic Bcl-2 and Bcl-xL proteins in scc-U2 cell lines compared to scc-U8. Our study suggests that the effectiveness of EGFR targeted PIT is not only dependent upon EGFR density. Intrinsic biological properties of tumor cell lines also play a role in determining the efficacy of targeted PIT. We have shown that in scc-U2 cells this difference may be caused by differences in the apoptopic pathway. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.
Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco
2013-01-01
A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) "true/false" SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved "true" zones could determine the corrosion rate in any of the zones.
Surface morphology of erbium silicide
NASA Technical Reports Server (NTRS)
Lau, S. S.; Pai, C. S.; Wu, C. S.; Kuech, T. F.; Liu, B. X.
1982-01-01
The surface of rare-earth silicides (Er, Tb, etc.), formed by the reaction of thin-film metal layers with a silicon substrate, is typically dominated by deep penetrating, regularly shaped pits. These pits may have a detrimental effect on the electronic performance of low Schottky barrier height diodes utilizing such silicides on n-type Si. This study suggests that contamination at the metal-Si or silicide-Si interface is the primary cause of surface pitting. Surface pits may be reduced in density or eliminated entirely through either the use of Si substrate surfaces prepared under ultrahigh vacuum conditions prior to metal deposition and silicide formation or by means of ion irradiation techniques. Silicide layers formed by these techniques possess an almost planar morphology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
K.E. Rasmuson
The U.S. Department of Energy has implemented a program to reclaim lands disturbed by site characterization at Yucca Mountain. Long term goals of the program are to re-establish processes on disturbed sites that will lead to self-sustaining plant communities. The Biological Opinion for Yucca Mountain Site Characterization Studies required that the U.S. Department of Energy develop a Reclamation Standards and Monitoring Plan to evaluate the success of reclamation efforts. According to the Reclamation Standards and Monitoring Plan, reclaimed sites will be monitored periodically, remediated if necessary, and eventually compared to an appropriate reference area to determine whether reclamation goals havemore » been achieved and the site can be released from further monitoring. Plant cover, density, and species richness (success parameters) on reclaimed sites are compared to 60 percent of the values (success criteria) for the same parameters on the reference area. Small sites (less than 0.1 ha) are evaluated for release using qualitative methods while large sites (greater than 0.1 ha) are evaluated using quantitative methods. In the summer of 2000, 31 small sites reclaimed in 1993 and 1994 were evaluated for reclamation success and potential release from further monitoring. Plant density, cover, and species richness were estimated on the C-Well Pipeline, UE-25 Large Rocks test site, and 29 ground surface facility test pits. Evidence of erosion, reproduction and natural recruitment, exotic species abundance, and animal use (key attributes) also were recorded for each site and used in success evaluations. The C-Well Pipeline and ground surface facility test pits were located in a ''Larrea tridentata - Ephedra nevadensis'' vegetation association while the UE-25 Large Rocks test site was located in an area dominated by ''Coleogyne ramosissima and Ephedra nevadensis''. Reference areas in the same vegetation associations with similar slope and aspect were chosen for comparison to the reclaimed sites. Sixty percent of the reference area means for density, cover, and species richness were compared to the estimated means for the reclaimed sites. Plant density, cover, and species richness at the C-Well Pipeline and UE-25 Large Rocks test site were greater than the success criteria and all key attributes indicated the sites were in acceptable condition. Therefore, these two sites were recommended for release from further monitoring. Of the 29 ground surface facility test pits, 26 met the criterion for density, 21 for cover, and 23 for species richness. When key attributes and conditions of the plant community near each pit were taken into account, 27 of these pits were recommended for release. Success parameters and key attributes at ground surface facility test pits 19 and 20 were inadequate for site release. Transplants of native species were added to these two sites in 2001 to improve density, cover, and species richness.« less
Lydsdottir, Linda B; Howard, Louise M; Olafsdottir, Halldora; Thome, Marga; Tyrfingsson, Petur; Sigurdsson, Jon F
2014-04-01
Few studies are available on the effectiveness of screening tools such as the Edinburgh Postnatal Depression Scale (EPDS) in pregnancy or the extent to which such tools may identify women with mental disorders other than depression. We therefore aimed to investigate the mental health characteristics of pregnant women who screen positive on the EPDS. Consecutive women receiving antenatal care in primary care clinics (from November 2006 to July 2011) were invited to complete the EPDS in week 16 of pregnancy. All women who scored above 11 (screen positive) on the EPDS and randomly selected women who scored below 12 (screen negative) were invited to participate in a psychiatric diagnostic interview. 2,411 women completed the EPDS. Two hundred thirty-three women (9.7%) were screened positive in week 16, of whom 153 (66%) agreed to a psychiatric diagnostic interview. Forty-eight women (31.4%) were diagnosed with major depressive disorder according to DSM-IV criteria, 20 (13.1%) with bipolar disorder, 93 (60.8%) with anxiety disorders (including 27 [17.6%] with obsessive-compulsive disorder [OCD]), 8 (5.2%) with dysthymia, 18 (11.8%) with somatoform disorder, 3 (2%) with an eating disorder, and 7 (4.6%) with current substance abuse. Women who screened positive were significantly more likely to have psychosocial risk factors, including being unemployed (χ(2)(1) = 23.37, P ≤.001), lower educational status (χ(2)(1)= 31.68, P ≤ .001), and a history of partner violence (χ(2)(1) = 10.30, P ≤ 001), compared with the women who screened negative. Use of the EPDS early in the second trimester of pregnancy identifies a substantial number of women with potentially serious mental disorders other than depression, including bipolar disorder, OCD, and eating disorders. A comprehensive clinical assessment is therefore necessary following use of the EPDS during pregnancy to ensure that women who screen positive receive appropriate mental health management. © Copyright 2014 Physicians Postgraduate Press, Inc.
NASA Technical Reports Server (NTRS)
Natesh, R.; Smith, J. M.; Bruce, T.; Oidwai, H. A.
1980-01-01
One hundred and seventy four silicon sheet samples were analyzed for twin boundary density, dislocation pit density, and grain boundary length. Procedures were developed for the quantitative analysis of the twin boundary and dislocation pit densities using a QTM-720 Quantitative Image Analyzing system. The QTM-720 system was upgraded with the addition of a PDP 11/03 mini-computer with dual floppy disc drive, a digital equipment writer high speed printer, and a field-image feature interface module. Three versions of a computer program that controls the data acquisition and analysis on the QTM-720 were written. Procedures for the chemical polishing and etching were also developed.
Electrophoretic Deposition on Porous Non-Conductors
NASA Technical Reports Server (NTRS)
Compson, Charles; Besra, Laxmidhar; Liu, Meilin
2007-01-01
A method of electrophoretic deposition (EPD) on substrates that are porous and electrically non-conductive has been invented. Heretofore, in order to perform an EPD, it has been necessary to either (1) use a substrate material that is inherently electrically conductive or (2) subject a non-conductive substrate to a thermal and/or chemical treatment to render it conductive. In the present method, instead of relying on the electrical conductivity of the substrate, one ensures that the substrate is porous enough that when it is immersed in an EPD bath, the solvent penetrates throughout the thickness, thereby forming quasi-conductive paths through the substrate. By making it unnecessary to use a conductive substrate, this method simplifies the overall EPD process and makes new applications possible. The method is expected to be especially beneficial in enabling deposition of layers of ceramic and/or metal for chemical and electrochemical devices, notably including solid oxide fuel cells.
Electrophoretic deposition of fluorescent Cu and Au sheets for light-emitting diodes
NASA Astrophysics Data System (ADS)
Liu, Jiale; Wu, Zhennan; Li, Tingting; Zhou, Ding; Zhang, Kai; Sheng, Yu; Cui, Jianli; Zhang, Hao; Yang, Bai
2015-12-01
Electrophoretic deposition (EPD) is a conventional method for fabricating film materials from nanometer-sized building blocks, and exhibits the advantages of low-cost, high-efficiency, wide-range thickness adjustment, and uniform deposition. Inspired by the interest in the application of two-dimensional (2D) nanomaterials, the EPD technique has been recently extended to building blocks with 2D features. However, the studies are mainly focused on simplex building blocks. The utilization of multiplex building blocks is rarely reported. In this work, we demonstrate a controlled EPD of Cu and Au sheets, which are 2D assemblies of luminescent Cu and Au nanoclusters. Systematic investigations reveal that both the deposition efficiency and the thickness are determined by the lateral size of the sheets. For Cu sheets with a large lateral size, a high ζ-potential and strong face-to-face van der Waals interactions facilitate the deposition with high efficiency. However, for Au sheets, the small lateral size and ζ-potential limit the formation of a thick film. To solve this problem, the deposition dynamics are controlled by increasing the concentration of the Au sheets and adding acetone. This understanding permits the fabrication of a binary EPD film by the stepwise deposition of Cu and Au sheets, thus producing a luminescent film with both Cu green emission and Au red emission. A white light-emitting diode prototype with color coordinates (x, y) = (0.31, 0.36) is fabricated by employing the EPD film as a color conversion layer on a 365 nm GaN clip and further tuning the amount of deposited Cu and Au sheets.Electrophoretic deposition (EPD) is a conventional method for fabricating film materials from nanometer-sized building blocks, and exhibits the advantages of low-cost, high-efficiency, wide-range thickness adjustment, and uniform deposition. Inspired by the interest in the application of two-dimensional (2D) nanomaterials, the EPD technique has been recently extended to building blocks with 2D features. However, the studies are mainly focused on simplex building blocks. The utilization of multiplex building blocks is rarely reported. In this work, we demonstrate a controlled EPD of Cu and Au sheets, which are 2D assemblies of luminescent Cu and Au nanoclusters. Systematic investigations reveal that both the deposition efficiency and the thickness are determined by the lateral size of the sheets. For Cu sheets with a large lateral size, a high ζ-potential and strong face-to-face van der Waals interactions facilitate the deposition with high efficiency. However, for Au sheets, the small lateral size and ζ-potential limit the formation of a thick film. To solve this problem, the deposition dynamics are controlled by increasing the concentration of the Au sheets and adding acetone. This understanding permits the fabrication of a binary EPD film by the stepwise deposition of Cu and Au sheets, thus producing a luminescent film with both Cu green emission and Au red emission. A white light-emitting diode prototype with color coordinates (x, y) = (0.31, 0.36) is fabricated by employing the EPD film as a color conversion layer on a 365 nm GaN clip and further tuning the amount of deposited Cu and Au sheets. Electronic supplementary information (ESI) available: Additional experimental information, and SEM images of Cu EPD films. See DOI: 10.1039/c5nr06599b
Santos, Iná S; Tavares, Beatriz Franck; Munhoz, Tiago N; Manzolli, Patricia; de Ávila, Gisele Bartz; Jannke, Eduardo; Matijasevich, Alicia
2017-01-21
Major depressive episodes (MDE) are frequent at the population level and are generally associated with severe symptoms that impair performance of activities of daily living of individuals suffering from this condition. The aim of this study was to compare the accuracy of two tests that separately showed suitable properties in screening for MDE: the Patient Health Questionnaire-9 (PHQ-9) and the Edinburgh Postnatal Depression Scale (EPDS). In a previous study, the sensitivity and specificity of the PHQ-9 and the EPDS in screening for MDE were compared with a structured diagnostic interview conducted by psychiatrics and psychologists using the Mini International Neuropsychiatric Interview as the gold standard. In a sample of adults living in the community in Pelotas, Brazil, the PHQ-9 and EPDS were applied at the same interview and the gold standard on a median of 17 days later. The interviews were carried out at the participant's home. 447 Individuals (191 men and 256 women) were assessed. The PHQ-9 and the EPDS results were concordant in 87.5% of the respondents, with a moderate agreement beyond what was expected by chance alone (kappa = 0.61). The areas below the ROC curves were not statistically different (82.1% for PHQ-9 and 83.5% for EPDS) (p = 0.291), thus indicating that the two tests had similar moderate accuracy. PHQ-9 and EPDS may be applied with equal confidence in screening for MDE in the community.
NASA Astrophysics Data System (ADS)
Shi, Binkai; Qiao, Pizhong
2018-03-01
Vibration-based nondestructive testing is an area of growing interest and worthy of exploring new and innovative approaches. The displacement mode shape is often chosen to identify damage due to its local detailed characteristic and less sensitivity to surrounding noise. Requirement for baseline mode shape in most vibration-based damage identification limits application of such a strategy. In this study, a new surface fractal dimension called edge perimeter dimension (EPD) is formulated, from which an EPD-based window dimension locus (EPD-WDL) algorithm for irregularity or damage identification of plate-type structures is established. An analytical notch-type damage model of simply-supported plates is proposed to evaluate notch effect on plate vibration performance; while a sub-domain of notch cases with less effect is selected to investigate robustness of the proposed damage identification algorithm. Then, fundamental aspects of EPD-WDL algorithm in term of notch localization, notch quantification, and noise immunity are assessed. A mathematical solution called isomorphism is implemented to remove false peaks caused by inflexions of mode shapes when applying the EPD-WDL algorithm to higher mode shapes. The effectiveness and practicability of the EPD-WDL algorithm are demonstrated by an experimental procedure on damage identification of an artificially-induced notched aluminum cantilever plate using a measurement system of piezoelectric lead-zirconate (PZT) actuator and scanning laser Doppler vibrometer (SLDV). As demonstrated in both the analytical and experimental evaluations, the new surface fractal dimension technique developed is capable of effectively identifying damage in plate-type structures.
Determinants of ante-partum depression: a multicenter study.
Balestrieri, Matteo; Matteo, Balestrieri; Isola, Miriam; Miriam, Isola; Bisoffi, Giulia; Giulia, Bisoffi; Calò, Salvatore; Salvatore, Calò; Conforti, Anita; Anita, Conforti; Driul, Lorenza; Lorenza, Driul; Marchesoni, Diego; Diego, Marchesoni; Petrosemolo, Paola; Paola, Petrosemolo; Rossi, Michela; Michela, Rossi; Zito, Adriana; Adriana, Zito; Zorzenone, Stefania; Stefania, Zorzenone; Di Sciascio, Guido; Guido, Di Sciascio; Leone, Roberto; Roberto, Leone; Bellantuono, Cesario; Cesario, Bellantuono
2012-12-01
Ante-partum depression (APD) is usually defined as a non-psychotic depressive episode of mild to moderate severity, beginning in or extending into pregnancy. APD has received less attention than postpartum depression. This is a cross-sectional study carried out in the Obstetrics and Gynaecology (OG) departments of four different general hospitals in Italy. Women attending consecutively the OG departments for their first ultrasound examination were asked to fill in the Edinburgh Postnatal Depression Scale (EPDS) in its Italian validated version. We used the total scores of the EPDS as a continuous variable for univariate and linear regression analyses; in accordance with the literature, the item analysis of EPDS was carried out by classifying the sample as women with "no depression" (scores 0-9), "possible depression" (scores 10-12), "probable depression" (scores 13+) and "probable APD" (scores 15+). The number of women recruited was 1,608. The EPDS assessment classified 10.9 % of the women as possibly depressed, 8.3 % as probably depressed and 4.7 % probably affected from an APD. EPDS score distribution was associated with nationality (higher scores for foreigners), cohabitation (higher scores for women living with friends or in a community), occupation (higher scores for housewives), past episodes of depression and use of herbal drugs. Non-depressed women had significantly lower values on all ten items as compared with depressed women, however, the pattern of item distribution on the EPDS scale remained similar across depression severity groups. In all four groups item 4 (anxious depression) attained the highest scores, while item 10 (suicidality) attained the lowest scores.
Santos, Iná S; Tavares, Beatriz Franck; Munhoz, Tiago N; Manzolli, Patricia; de Ávila, Gisele Bartz; Jannke, Eduardo; Matijasevich, Alicia
2016-09-27
Major depressive episodes (MDE) are frequent at the population level and are generally associated with severe symptoms that impair performance of activities of daily living of individuals suffering from this condition. The aim of this study was to compare the accuracy of two tests that separately showed suitable properties in screening for MDE: the Patient Health Questionnaire-9 (PHQ-9) and the Edinburgh postnatal depression scale (EPDS). In a previous study, the sensitivity and specificity of the PHQ-9 and the EPDS in screening for MDE were compared with a structured diagnostic interview conducted by psychiatrics and psychologists using the Mini International Neuropsychiatric Interview as the gold standard. In a sample of adults living in the community in Pelotas, Brazil, the PHQ-9 and EPDS were applied at the same interview and the gold standard on a median of 17 days later. The interviews were carried out at the participant's home. 447 individuals (191 men and 256 women) were assessed. The PHQ-9 and the EPDS results were concordant in 87.5 % of the respondents, with a moderate agreement beyond what was expected by chance alone (kappa = 0.61). The areas below the ROC curves were not statistically different (82.1 % for PHQ-9 and 83.5 % for EPDS) (p = 0.291), thus indicating that the two tests had similar moderate accuracy. PHQ-9 and EPDS may be applied with equal confidence in screening for MDE in the community.
NASA Astrophysics Data System (ADS)
Sharma, Mala M.; Ziemian, Constance W.
2008-12-01
The stress corrosion cracking (SCC) behavior of two developmental nanocrystalline 5083 alloys with varied composition and processing conditions was studied. The results were compared to a commercial aluminum AA 5083 (H111) alloy. The pitting densities, size and depths, and residual tensile strengths were measured after alternate immersion in artificial seawater and atmospheric exposure under different loading conditions. Optical and scanning electron microscopy (SEM) with EDX was used to analyze the fracture surfaces of failed specimen after removal at selected intervals and tensile testing. One of the nanostructured Al-Mg alloys exhibited significantly superior pitting resistance when compared to conventional microstructured AA 5083. Under conditions where pitting corrosion showed up as local tunnels toward phase inclusions, transgranular cracking was observed, whereas under conditions when pitting corrosion evolved along grain boundaries, intergranular cracking inside the pit was observed. Pit initiation resistance of the nano alloys appears to be better than that of the conventional alloys. However, long-term pit propagation is a concern and warrants further study. The objective of this investigation was to obtain information regarding the role that ultra-fine microstructures play in their degradation in marine environments and to provide insight into the corrosion mechanisms and damage processes of these alloys.
Computational fluid dynamics models of conifer bordered pits show how pit structure affects flow.
Schulte, Paul J
2012-02-01
• The flow of xylem sap through conifer bordered pits, particularly through the pores in the pit membrane, is not well understood, but is critical for an understanding of water transport through trees. • Models solving the Navier-Stokes equation governing fluid flow were based on the geometry of bordered pits in black spruce (Picea mariana) and scanning electron microscopy images showing details of the pores in the margo of the pit membrane. • Solutions showed that the pit canals contributed a relatively small fraction of resistance to flow, whereas the torus and margo pores formed a large fraction, which depended on the structure of the individual pit. The flow through individual pores in the margo was strongly dependent on pore area, but also on the radial location of the pore with respect to the edge of the torus. • Model results suggest that only a few per cent of the pores in the margo account for nearly half of the flow and these pores tend to be located in the inner region of the margo where their contribution will be maximized. A high density of strands in outer portions of the margo (hence narrower pores) may be more significant for mechanical support of the torus. © 2011 The Author. New Phytologist © 2011 New Phytologist Trust.
Jupiter radiation measurements from enhanced Galileo/EPD data for NASA's PDS archive
NASA Astrophysics Data System (ADS)
Kollmann, P.; Smith, D.; Vandegriff, J. D.; Paranicas, C.; Lee-Payne, Z. H.
2017-12-01
The Galileo mission included the first orbiter around Jupiter. Its Energetic Particle Detector (EPD) provided an excellent survey of the radiation in this planetary magnetosphere. EPD measured electrons and various ion species in the energy range of tens of keV to tens of MeV. This data set is unique since the orbit was close to the equatorial plane, covered distances from Jupiter to its magnetopause, and included several close flybys at moons. The ongoing Juno mission in comparison only skims the equatorial plane and does not include moon flybys. Even though the Galileo mission ended in 2003, the EPD data archived through NASA's Planetary Data System (PDS) is sparse and not well calibrated. The bulk of the PDS data is from a low time resolution mode (from Galileo's "real time" mode), and is only provided as count rates. Only the 14 directionally resolved channels are provided in the PDS, but there would be also 35 additional omnidirectional channels available. Data in the higher time resolution "record mode" is archived but has not been adequately corrected. We present a preliminary version of fully cleaned, calibrated, and corrected EPD data that can be used without specialized instrument knowledge. Archive products for both the updated data and also the initial raw data (all channels and resolutions) are being prepared for delivery to the PDS. Major issues with the data from the Low Energy Magnetospheric Measurements System (EPD/LEMMS) were that some channels were saturated or contaminated. We correct for this using dead times and background values determined in flight. The raw measurements of electrons in the MeV range are not resolved in energy. We ran a forward model considering the instrument response to calculate electron MeV range spectra, which have many applications. From the Composition Measurement System (EPS/CMS), we have also extracted event data, which will also be included in our PDS delivery and can be used to derive high-resolution energy spectra. The processed EPD radiation data can be applied to a wide range of studies, from mission design to scientific studies on Jupiter's magnetosphere. Prior to publication in the PDS archive, a preliminary set of comma-delimited text files containing the newly processed data can be accessed at http://sd-www.jhuapl.edu/Galileo_EPD/
White, R R; Brady, M; Capper, J L; McNamara, J P; Johnson, K A
2015-06-01
Optimizing efficiency in the cow-calf sector is an important step toward improving beef sustainability. The objective of the study was to use a model to identify the relative roles of reproductive, genetic, and nutritional management in minimizing beef production systems' environmental impact in an economically viable, socially acceptable manner. An economic and environmental diet optimizer was used to identify ideal nutritional management of beef production systems varying in genetic and reproductive technology use. Eight management scenarios were compared to a least cost baseline: average U.S. production practices (CON), CON with variable nutritional management (NUT), twinning cattle (TWN), early weaning (EW), sire selection by EPD using either on-farm bulls (EPD-B) or AI (EPD-AI), decreasing the calving window (CW), or selecting bulls by EPD and reducing the calving window (EPD-CW). Diets to minimize land use, water use, and/or greenhouse gas (GHG) emissions were optimized under each scenario. Increases in diet cost attributable to reducing environmental impact were constrained to less than stakeholder willingness to pay for improved efficiency and reduced environmental impact. Baseline land use, water use, and GHG emissions were 188 m, 712 L, and 21.9 kg/kg HCW beef. The NUT scenario, which assessed opportunities to improve sustainability by altering nutritional management alone, resulted in a simultaneous 1.5% reduction in land use, water use, and GHG emissions. The CW scenario improved calf uniformity and simultaneously decreased land use, water use, and GHG emissions by 3.2%. Twinning resulted in a 9.2% reduction in the 3 environmental impact metrics. The EW scenario allowed for an 8.5% reduction in the 3 metrics. The EPD-AI scenario resulted in an 11.1% reduction, which was comparable to the 11.3% reduction achieved by EPD-B in the 3 metrics. Improving genetic selection by using AI or by purchasing on-farm bulls based on their superior EPD demonstrated clear opportunity to improve sustainability. When genetic and reproductive technologies were adopted, up to a 12.4% reduction in environmental impact was achievable. Given the modeling assumptions used in this study, optimizing nutritional management while concurrently improving genetic and reproductive efficiency may be promising avenues to improve productivity and sustainability of U.S. beef systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Lunyong; Sun Jianfei, E-mail: jfsun_hit@263.net; Zuo Hongbo
2012-08-15
The tridimensional morphology and etching kinetics of the etch pit on the C-{l_brace}0 0 0 1{r_brace} plane of sapphire crystal ({alpha}-Al{sub 2}O{sub 3}) in molten KOH were studied experimentally. It was shown that the etch pit takes on tridimensional morphologies with triangular symmetry same as the symmetric property of the sapphire crystal. Pits like centric and eccentric triangular pyramid as well as hexagonal pyramid were observed, but the latter is less in density. In-depth analyses show the side walls of the etch pits belong to the {l_brace}1 1{sup Macron} 0 2{sup Macron }{r_brace} family, and the triangular pit contains edgesmore » full composed by Al{sup 3+} ions on the etching surface so it is more stable than the hexagonal pit since its edges on the etching surface contains Al{sup 2+} ions. The etch pits developed in a manner of kinematic wave by the step moving with constant speed, which is controlled by the chemical reaction with activation energy of 96.6 kJ/mol between Al{sub 2}O{sub 3} and KOH. - Graphical abstract: Schematic showing the atomic configuration of the predicted side walls of regular triangular pyramid shaped etch pit on the C-{l_brace}0 0 0 1{r_brace} plane of sapphire crystal. Highlights: Black-Right-Pointing-Pointer Observed the tridimensional morphology of etch pits. Black-Right-Pointing-Pointer Figured out the atomic configuration origin of the etch pits. Black-Right-Pointing-Pointer Quantitatively determined the etch rates of the etch pits.« less
Accounting for discovery bias in genomic EPD
USDA-ARS?s Scientific Manuscript database
Genomics has contributed substantially to genetic improvement of beef cattle. The implementation is through computation of genomically enhanced expected progeny differences (GE-EPD), which are predictions of genetic merit of individual animals based on genomic information, pedigree, and data on the ...
NASA Technical Reports Server (NTRS)
Robinson, W. W.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the Electrical Power Distribution and Control (EPD and C)/Remote Manipulator System (RMS) hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained in the NASA FMEA/CIL documentation. This report documents the results of the independent analysis of the EPD and C/RMS (both port and starboard) hardware. The EPD and C/RMS subsystem hardware provides the electrical power and power control circuitry required to safely deploy, operate, control, and stow or guillotine and jettison two (one port and one starboard) RMSs. The EPD and C/RMS subsystem is subdivided into the four following functional divisions: Remote Manipulator Arm; Manipulator Deploy Control; Manipulator Latch Control; Manipulator Arm Shoulder Jettison; and Retention Arm Jettison. The IOA analysis process utilized available EPD and C/RMS hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based on the severity of the effect for each failure mode.
[Effect of paternity leave on maternal postpartum depression].
Séjourné, N; Beaumé, M; Vaslot, V; Chabrol, H
2012-06-01
The aim of this study was to explore the role of the paternity leave in the appearance of the maternal postpartum depression. Fifty-one couples took part in the whole study. Between the second and the fifth day after the childbirth, the mother completed the Edinburgh Postnatal Depression Scale (EPDS), which measures the symptoms of depression and the Multidimensional Scale of Perceived Social Support (MSPSS) which measures the social support the mother has become. The father completed the EPDS. Two months and then the second time four months after the childbirth, the mother received the EPDS, the MSPSS, and questionnaires measuring the temperament of the baby, the maternal skills, the feeling of being a mother and the quality of life postpartum. In order to evaluate the paternal involvement, the father completed the EPDS and questions about paternal skills and involvement. The paternity leave seemed not to have any consequences on the results at the EPDS or other questionnaires. However, lack of paternal involvement was a significant predictor of the intensity of the depressive symptoms of the mothers. It is not the presence of the father wich seems important to take into account for detection and the traitement of postpatum depression but his participation in the care of the baby. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
Orbital processing of high-quality CdTe compound semiconductors
NASA Technical Reports Server (NTRS)
Larson, David J., Jr.; Alexander, J. I. D.; Gillies, D.; Carlson, F. M.; Wu, J.; Black, D.
1994-01-01
CdZnTe crystals were grown in one-g and in micro-g for comparative analysis. The two micro-g crystals were grown in the Crystal Growth Furnace during the First United States Microgravity Laboratory mission (USML-1). The samples were analyzed for chemical homogeneity, structural perfection, and optoelectronic performance (infrared transmission). Fourier Transform Infrared (FTIR) transmission of both ground and flight materials showed that the infrared transmission was close to theoretical, 63% versus 66%, suggesting that the material was close to the stochiometric composition during both the ground and flight experiments. Infrared microscopy confirmed that the principal precipitates were Te and their size (1-10 microns) and density suggested that the primary flight and ground base samples experienced similar cooling rates. Macrosegregation was predicted, using scaling analysis, to be low even in one-g crystals and this was confirmed experimentally, with nearly diffusion controlled growth achieved even in the partial mixing regime on the ground. Radial segregation was monitored in the flight samples and was found to vary with fraction solidified, but was disturbed due to the asymmetric grvitational and thermal fields experienced by the flight samples. The flight samples, however, were found to be much higher in structural perfection than the ground samples produced in the same furnace under identical growth conditions except for the gravitational level. Rocking curve widths were found to be substantially reduced, from 20/35 (one-g) to 9/20 (micro-g) for the best regions of the crystals. The full width at half maximum (FWHM) of 9 arc seconds is as good as the best reported terrestrially for this material. The ground samples were found to have a fully developed mosaic structure consisting of subgrains, whereas the flight sample dislocations were discrete and no mosaic substructure was evident. The defect density was reduced from 50-100,000 (one-g) to 500-25000 EPD (micro-g). These results were confirmed using rocking curve analysis, synchrotron topography, and etch pit analysis. The low dislocation density is thought to have resulted from the near-absence of hydrostatic pressure which allowed the melt to solidify with minimum or no wall contact, resulting in very low stress being exerted on the crystal during growth or during post-solidification cooling.
The Savannah River Site's Groundwater Monitoring Program, third quarter 1991
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site's (SRS) Groundwater Monitoring Program. During third quarter 1991, EPD/EMS conducted extensive sampling of monitoring wells. Analytical results from third quarter 1991 are listed in this report.
Vallet-Regí, M; Izquierdo-Barba, I; Gil, F J
2003-11-01
Sol-gel films on austenitic stainless steel (AISI 316L) polished wafer were prepared from sono-sols obtained from tetraethylorthosilane and hydrated calcium nitrate. However, pitting was observed in different places on the stainless steel surfaces. The corrosion resistance was evaluated by the polarization resistance in simulated body fluid environment at 37 degrees C. The critical current density, the passive current density, the corrosion potential, and the critical pitting potential were studied. The austenitic stainless steel 316L treated presents important electrochemical corrosion and consequently its application as endosseous implants is not possible. Copyright 2003 Wiley Periodicals, Inc.
Psychiatric disorder and work life: A longitudinal study of intra-generational social mobility.
Tiikkaja, Sanna; Sandin, Sven; Hultman, Christina M; Modin, Bitte; Malki, Ninoa; Sparén, Pär
2016-03-01
Intra-generational social mobility, which describes the mobility within an individual's own working life, is seldom studied among employees with psychiatric disorders (EPD). There is need of knowledge of the intra-generational mobility patterns, in a broader perspective, among EPD. To investigate intra-generational social mobility in employed individuals diagnosed with affective disorder, personality disorder, schizophrenia and drug dependence in a national Swedish cohort. We identified a national sample of employed Swedish adults born in 1939-1949 (N = 876, 738), and among them individuals with a first-time hospital admission for affective psychosis, neurosis and personality disorder, alcoholism, drug dependence or schizophrenia in 1964-1980 (N = 18, 998). Employed individuals without hospital admission for such diagnoses were utilised as a comparison group (N = 866, 442). Intra-individual social class changes between 1980 and 1990 among EPD and the comparison group were described through summary statistics and graphs. EPD more often held Low manual occupations at baseline in 1980 than the comparison group (44% vs. 28%), although parental social class was similar. In 1990, 19% of EPD and 4% of the comparison group had lost contact with the labour market. Social stability was less common among EPD (49 %) than in the comparison group (67%). Mobility out of the labour force increased and social stability decreased by number of inpatient admissions. Employees diagnosed with affective psychosis or neurosis and personality disorder fared better in the labour market than employees with schizophrenia. Employees suffering from psychiatric disorder do not maintain their social class or remain in the labour force to the same extent as individuals without those problems, irrespective of their parental class. Our results support the social drift hypothesis that individuals with poor psychiatric health move downward in the social hierarchy. © The Author(s) 2015.
The Savannah River Site`s Groundwater Monitoring Program, third quarter 1991
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site`s (SRS) Groundwater Monitoring Program. During third quarter 1991, EPD/EMS conducted extensive sampling of monitoring wells. Analytical results from third quarter 1991 are listed in this report.
The Savannah River Site`s groundwater monitoring program. Third quarter 1990
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-05-06
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site`s (SRS) Groundwater Monitoring Program. During third quarter 1990 (July through September) EPD/EMS conducted routine sampling of monitoring wells and drinking water locations. EPD/EMS established two sets of flagging criteria in 1986 to assist in the management of sample results. The flagging criteria do not define contamination levels; instead they aid personnel in sample scheduling, interpretation of data, and trend identification. The flagging criteria are based on detection limits, background levels in SRS groundwater, and drinking water standards. All analytical results from third quarter 1990 are listed in thismore » report, which is distributed to all site custodians. One or more analytes exceeded Flag 2 in 87 monitoring well series. Analytes exceeded Flat 2 for the first since 1984 in 14 monitoring well series. In addition to groundwater monitoring, EPD/EMS collected drinking water samples from SRS drinking water systems supplied by wells. The drinking water samples were analyzed for radioactive constituents.« less
The Savannah River Site's groundwater monitoring program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-05-06
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site's (SRS) Groundwater Monitoring Program. During third quarter 1990 (July through September) EPD/EMS conducted routine sampling of monitoring wells and drinking water locations. EPD/EMS established two sets of flagging criteria in 1986 to assist in the management of sample results. The flagging criteria do not define contamination levels; instead they aid personnel in sample scheduling, interpretation of data, and trend identification. The flagging criteria are based on detection limits, background levels in SRS groundwater, and drinking water standards. All analytical results from third quarter 1990 are listed in thismore » report, which is distributed to all site custodians. One or more analytes exceeded Flag 2 in 87 monitoring well series. Analytes exceeded Flat 2 for the first since 1984 in 14 monitoring well series. In addition to groundwater monitoring, EPD/EMS collected drinking water samples from SRS drinking water systems supplied by wells. The drinking water samples were analyzed for radioactive constituents.« less
NASA Technical Reports Server (NTRS)
Mccants, C. N.; Bearrow, M.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Distribution and Control/Electrical Power Generation (EPD and C/EPG) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison was provided through additional analysis as required. The results of that comparison is documented for the Orbiter EPD and C/EPG hardware. The IOA product for the EPD and C/EPG analysis consisted of 263 failure mode worksheets that resulted in 42 potential critical items being identified. Comparison was made to the NASA baseline which consisted of 211 FMEA and 47 CIL items.
Yang, Yang; Chen, Dingqiong; Liu, Bo; Zhao, Jinbao
2015-04-15
A binder-free silicon (Si) based electrode for lithium-ion battery was fabricated in an organic solvent through one-step electrophoretic deposition (EPD). The nanosized Si and acetylene black (AB) particles were bonded tightly together to form a homogeneous co-deposited film with 3D porous structure through the EPD process. The 3D porous structure provides buffer spaces to alleviate the mechanical stress due to silicon volume change during the cycling and improves lithium-ion conductivity by shortening ion diffusion length and better ion conducting pathway. The electrode prepared with 5 s deposition duration shows the best cycling performance among electrodes fabricated by EPD method, and thus, it was selected to be compared with the silicon electrode prepared by the conventional method. Our results demonstrate that the Si nanoparticle electrode prepared through EPD exhibits smaller cycling capacity decay rate and better rate capability than the electrode prepared by the conventional method.
Electrophoretic co-deposition of PEEK-hydroxyapatite composite coatings for biomedical applications.
Baştan, Fatih E; Atiq Ur Rehman, Muhammad; Avcu, Yasemin Yıldıran; Avcu, Egemen; Üstel, Fatih; Boccaccini, Aldo R
2018-05-03
This study focuses on the optimization of electrophoretic deposition (EPD) and suspension parameters for producing PEEK-hydroxyapatite (HA) coatings with feasible microstructure, adhesion strength, and in-vitro bioactivity. Nanostructured hydroxyapatite (HA) micro-granules were incorporated with PEEK to form PEEK-hydroxyapatite composite coatings via EPD. After EPD, a heat-treatment at 375 °C was applied for densification of the coatings and for enhancing the adhesion between the coatings and the substrates. It was found that both adhesion strength and in-vitro bioactivity of the coatings were dependent on the PEEK and HA relative contents. Thus, increasing the amount of HA improved the bioactivity while decreased the adhesion strength of the coatings. Apatite-like layer formation was observed on coatings with high HA content after incubation for three days in simulated body fluid (SBF). Finally, a deposition mechanism was proposed for the EPD of the PEEK-hydroxyapatite composite system. Copyright © 2018 Elsevier B.V. All rights reserved.
Electrophoretic deposition (EPD): Mechanisms, kinetics, and application to ceramics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarkar, P.; Nicholson, P.S.
1996-08-01
The mechanisms of electrophoretic deposition (EPD) are discussed and their shortcomings identified. The kinetics of the processes involved are analyzed for constant-current and constant-voltage conditions. A method of determining the Hamaker constant of suspended particles is developed by modeling the relationship between the particle interaction energy and the suspension stability. A three-probe dc technique is used to map the voltage profile around the depositing electrode, and the results are used to explain discrepancies between the calculated and experimentally observed voltage drops during deposition. A mechanism of deposition is proposed based on DLVO theory and particle double-layer distortion/thinning on application ofmore » a dc field to the suspension. Kinetic equations are developed for constant-current and constant-voltage EPD using mass balance conditions; these are verified by experiments. After the phenomenon is introduced and discussed, a critique of the application of EPD to the synthesis of ceramic shapes and coatings is given.« less
Anxiety and stress in the postpartum: is there more to postnatal distress than depression?
Miller, Renée L; Pallant, Julie F; Negri, Lisa M
2006-03-24
Postnatal depression has received considerable research and clinical attention, however anxiety and stress in the postpartum has been relatively ignored. Along with the widespread use of the Edinburgh Postnatal Depression Scale (EPDS), depression has become the marker for postnatal maladjustment. Symptoms of anxiety tend to be subsumed within diagnoses of depression, which can result in anxiety being minimized or overlooked in the absence of depression. Some researchers have identified the need to distinguish between postnatal depression and anxiety, and to discern cases where depression and anxiety co-exist. The aim of this study was to assess the prevalence of postnatal distress using the EPDS and the Depression Anxiety Stress Scales (DASS-21). As part of a larger cross-sectional study, the EPDS and DASS-21 were administered to a convenience sample of 325 primiparous mothers, who ranged in age from 18 to 44 years (M = 32 years). Recruited through mother's groups and health centres in Melbourne Australia, inclusion was limited to mothers whose babies were aged between 6 weeks and 6 months. Analyses included comparisons between the classifications of women according to the EPDS and the DASS-21, and an exploration of the extent to which the EPDS identified anxious-depressed women. The EPDS identified 80 women (25%) as possibly depressed (using a cut-off of over 9), of which the DASS-21 corroborated 58%. In the total sample, 61 women (19%) were classified by the DASS-21 to be depressed. Using broader criteria for distress, it was revealed by the DASS-21 that a further 33 women (10%) showed symptoms of anxiety and stress without depression. A total of 41 women (13%) had symptoms of anxiety either in isolation or in combination with depression. The DASS-21 identified 7% of the sample as being both anxious and depressed. This at-risk sub-group had higher mean EPDS and DASS-depression scores than their depressed-only counterparts. The prevalence of anxiety and stress in the present study points to the importance of assessing postnatal women for broader indicators of psychological morbidity than that of depression alone. The DASS-21 appears to be a useful instrument for this purpose.
Ramos, Rogelio; Zlatev, Roumen; Valdez, Benjamin; Stoytcheva, Margarita; Carrillo, Mónica; García, Juan-Francisco
2013-01-01
A virtual instrumentation (VI) system called VI localized corrosion image analyzer (LCIA) based on LabVIEW 2010 was developed allowing rapid automatic and subjective error-free determination of the pits number on large sized corroded specimens. The VI LCIA controls synchronously the digital microscope image taking and its analysis, finally resulting in a map file containing the coordinates of the detected probable pits containing zones on the investigated specimen. The pits area, traverse length, and density are also determined by the VI using binary large objects (blobs) analysis. The resulting map file can be used further by a scanning vibrating electrode technique (SVET) system for rapid (one pass) “true/false” SVET check of the probable zones only passing through the pit's centers avoiding thus the entire specimen scan. A complete SVET scan over the already proved “true” zones could determine the corrosion rate in any of the zones. PMID:23691434
NASA Astrophysics Data System (ADS)
Kasu, Makoto; Oshima, Takayoshi; Hanada, Kenji; Moribayashi, Tomoya; Hashiguchi, Akihiro; Oishi, Toshiyuki; Koshi, Kimiyoshi; Sasaki, Kohei; Kuramata, Akito; Ueda, Osamu
2017-09-01
A pixel array of vertical Schottky-barrier diodes (SBDs) was fabricated and measured on the surface of a (\\bar{2}01) β-Ga2O3 single crystal. Subsequently, etch pits and patterns were observed on the same surface. Three types of etch pits were discovered: (1) a line-shaped etch pattern originating from a void and extending toward the [010] direction, (2) an arrow-shaped etch pit whose arrow’s head faces toward the [102] direction and, (3) a gourd-shaped etch pit whose point head faces toward the [102] direction. Their average densities were estimated to be 5 × 102, 7 × 104, and 9 × 104 cm-2, respectively. We confirmed no clear relationship between the leakage current in SBDs and these crystalline defects. Such results are obtained because threading dislocations run mainly in the [010] growth direction and do not go through the (\\bar{2}01) sample plate.
NASA Astrophysics Data System (ADS)
Daryakenari, Ahmad Ahmadi; Daryakenari, Mohammad Ahmadi; Omidvar, Hamid
2018-01-01
To acquire highly efficient and cost-effective fuel cells, numerous research works have been carried out to the development low cost and excellent performance of electrocatalysts. In this paper, a solution-based electrophoretic deposition (EPD) technique for fabrication of Pt-based catalyst layers is studied. Nanographitic flake coatings used as catalyst support for sputtered platinium (Pt) were fabricated via the electrophoretic deposition (EPD) of dispersed nanographitic flakes in isopropyl alcohol. Magnesium nitrate hexahydrate (MNH) was used as an additive binder in the EPD process. Subsequently, the platinium particles were deposited by a direct sputtering on the fabricated nanographitic flake coatings.
Corrosion of carbon steels, stainless steels, and titanium in aqueous lithium bromide solution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guinon, J.L.; Garcia-Anton, J.; Perez-Herranz, V.
1994-03-01
Effects of lithium bromide (LiBr) concentration, pH, temperature, exposure time, and the action of some inhibitors on corrosion of several carbon (C) steels, stainless steels (SS), and a titanium (Ti) alloy were studied. Corrosion rates were determined by the polarization resistance method and compared to rates determined by weight-loss measurements. Pitting potentials (E[sub p]) were evaluated in neutral LiBr solution and with different inhibitors. Pit density and average pit depth depended on the metal tested, with lowest values for Ti, the next lowest values for type 316 SS (UNS S31600), and the highest values for UNS G41350 tempered steel.
Shi, Kaiyuan; Zhitomirsky, Igor
2013-10-01
Thin films of multiwalled carbon nanotubes (MWCNT), graphene and polypyrrole (PPy) nanofibers were prepared by cathodic electrophoretic deposition (EPD) from aqueous suspensions, containing safranin (SAF) as a new dispersant. The results of Fourier transform infrared spectroscopy, UV-Vis spectroscopy studies and sedimentation tests, coupled with deposition yield and electron microscopy data showed that SAF adsorbed on MWCNT, graphene and PPy, provided their dispersion and charging in the suspensions and allowed efficient EPD. The deposition yield can be controlled by the variation of SAF concentration in the suspensions and deposition time. The use of SAF as a co-dispersant for MWCNT, graphene and PPy, allowed controlled EPD of composite graphene-MWCNT and graphene-PPy films. The proposed approach for the deposition of PPy paves the way for EPD of neutral polymers using organic dyes as dispersing and charging agents. The composite films were investigated for application in electrochemical supercapacitors (ES). The graphene-MWCNT and graphene-PPy films showed significant increase in capacitance, decrease in resistance and increase in capacitance retention at high charge-discharge rates compared to the films of individual components. The analysis of electrochemical testing results and electron microscopy data provided an insight into the influence of composite microstructure on electrochemical performance. The composites, prepared by EPD are promising materials for electrodes of ES. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Nada, Mohamed Y.; Othman, Mohamed A. K.; Capolino, Filippo
2017-11-01
We present an approach and a theoretical framework for generating high-order exceptional points of degeneracy (EPDs) in photonic structures based on periodic coupled resonator optical waveguides (CROWs). Such EPDs involve the coalescence of Floquet-Bloch eigenwaves in CROWs, without the presence of gain and loss, which contrasts with the parity-time symmetry required to develop exceptional points based on gain and loss balance. The EPDs arise here by introducing symmetry breaking in a conventional chain of coupled resonators through periodic coupling to an adjacent uniform optical waveguide, which leads to unique modal characteristics that cannot be realized in conventional CROWs. Such remarkable characteristics include high quality factors (Q factors) and strong field enhancement, even without any mirrors at the two ends of a cavity. We show for the first time the capability of CROWs to exhibit EPDs of various orders, including the degenerate band edge (DBE) and the stationary inflection point. The proposed CROW of finite length shows an enhanced quality factor when operating near the DBE, and the Q factor exhibits an unconventional scaling with the CROW's length. We develop the theory of EPDs in such unconventional CROW using coupled-wave equations, and we derive an analytical expression for the dispersion relation. The proposed unconventional CROW concepts have various potential applications including Q switching, nonlinear devices, lasers, and extremely sensitive sensors.
Engberg, Elina; Stach-Lempinen, Beata; Sahrakorpi, Niina; Rönö, Kristiina; Roine, Risto P; Kautiainen, Hannu; Eriksson, Johan G; Koivusalo, Saila B
2015-12-01
To examine differences in antenatal depressive symptoms between women at high risk for gestational diabetes mellitus (GDM) and pregnant women in the general population. We recruited pregnant women at high risk for GDM, based on a history of GDM and/or prepregnancy BMI ≥ 30 kg/m(2), (n = 482) and pregnant women in the general population (n = 358) before 20 weeks of gestation. Depressive symptoms were assessed by the Edinburgh Postnatal Depression Scale (EPDS). Of the women at high risk for GDM, 17% had an EPDS score ≥ 10 (indicating risk for depression) compared to 11% of the pregnant women in the general population (p = .025). The mean EPDS score was also higher in the women at risk for GDM (5.5, SD 4.5 vs. 4.6, SD 3.9, p = .004, effect size 0.21 [95% CI: 0.07 to 0.34]). After adjusting for age, prepregnancy BMI and income, the difference between the groups was no longer significant either in the proportion of women having an EPDS score ≥ 10 (p = .59) or in the mean EPDS score (p=.39). After controlling for age, prepregnancy BMI and income, women at high risk for GDM did not have greater depressive symptoms compared to pregnant women in the general population in early pregnancy. Copyright © 2015 Elsevier Inc. All rights reserved.
Household food insecurity is associated with depressive symptoms among low-income pregnant Latinas
Hromi-Fiedler, Amber; Bermúdez-Millán, Angela; Segura-Pérez, Sofia; Pérez-Escamilla, Rafael
2010-01-01
Latinas experience high rates of poverty, household food insecurity, and prenatal depression. To date, only one U.S. study has examined the relationship between household food insecurity and prenatal depression, yet it focused primarily on non-Latina white and non-Latina Black populations. Therefore, this study examined the independent association of household food insecurity with depressive symptoms among low-income pregnant Latinas. This cross-sectional study included 135 low income pregnant Latinas living in Hartford, Connecticut. Women were assessed at enrollment for household food security during pregnancy using an adapted and validated version of the U.S. Household Food Security Survey Module. Prenatal depressive symptoms were assessed using the Center for Epidemiological Studies Depression Scale (CES-D). A cutoff of ≥ 21 was used to indicate elevated levels of prenatal depressive symptoms (EPDS). Multivariate backwards stepwise logistic regression was used to identify risk factors for EPDS. Almost one third of participants had EPDS. Women who were food insecure were more likely to experience EPDS compared to food secure women (OR=2.59; 95% CI=1.03–6.52). Being primiparous, experiencing heartburn and reporting poor/fair health during pregnancy, as well as having a history of depression were also independent risk factors for experiencing EPDS. Findings from this study suggest the importance of assessing household food insecurity when evaluating depression risk among pregnant Latinas. PMID:20735732
Fabrication and kinetics study of nano-Al/NiO thermite film by electrophoretic deposition.
Zhang, Daixiong; Li, Xueming
2015-05-21
Nano-Al/NiO thermites were successfully prepared as film by electrophoretic deposition (EPD). For the key issue of this EPD, a mixture solvent of ethanol-acetylacetone (1:1 in volume) containing 0.00025 M nitric acid was proved to be a suitable dispersion system for EPD. The kinetics of electrophoretic deposition for both nano-Al and nano-NiO were investigated; the linear relation between deposition weight and deposition time in short time and parabolic relation in prolonged time were observed in both EPDs. The critical transition time between linear deposition kinetics and parabolic deposition kinetics for nano-Al and nano-NiO were 20 and 10 min, respectively. The theoretical calculation of the kinetics of electrophoretic deposition revealed that the equivalence ratio of nano-Al/NiO thermites film would be affected by the behavior of electrophoretic deposition for nano-Al and nano-NiO. The equivalence ratio remained steady when the linear deposition kinetics dominated for both nano-Al and nano-NiO. The equivalence ratio would change with deposition time when deposition kinetics for nano-NiO changed into parabolic kinetics dominated after 10 min. Therefore, the rule was suggested to be suitable for other EPD of bicomposites. We also studied thermodynamic properties of electrophoretic nano-Al/NiO thermites film as well as combustion performance.
Improved data visualization techniques for analyzing macromolecule structural changes.
Kim, Jae Hyun; Iyer, Vidyashankara; Joshi, Sangeeta B; Volkin, David B; Middaugh, C Russell
2012-10-01
The empirical phase diagram (EPD) is a colored representation of overall structural integrity and conformational stability of macromolecules in response to various environmental perturbations. Numerous proteins and macromolecular complexes have been analyzed by EPDs to summarize results from large data sets from multiple biophysical techniques. The current EPD method suffers from a number of deficiencies including lack of a meaningful relationship between color and actual molecular features, difficulties in identifying contributions from individual techniques, and a limited ability to be interpreted by color-blind individuals. In this work, three improved data visualization approaches are proposed as techniques complementary to the EPD. The secondary, tertiary, and quaternary structural changes of multiple proteins as a function of environmental stress were first measured using circular dichroism, intrinsic fluorescence spectroscopy, and static light scattering, respectively. Data sets were then visualized as (1) RGB colors using three-index EPDs, (2) equiangular polygons using radar charts, and (3) human facial features using Chernoff face diagrams. Data as a function of temperature and pH for bovine serum albumin, aldolase, and chymotrypsin as well as candidate protein vaccine antigens including a serine threonine kinase protein (SP1732) and surface antigen A (SP1650) from S. pneumoniae and hemagglutinin from an H1N1 influenza virus are used to illustrate the advantages and disadvantages of each type of data visualization technique. Copyright © 2012 The Protein Society.
Improved data visualization techniques for analyzing macromolecule structural changes
Kim, Jae Hyun; Iyer, Vidyashankara; Joshi, Sangeeta B; Volkin, David B; Middaugh, C Russell
2012-01-01
The empirical phase diagram (EPD) is a colored representation of overall structural integrity and conformational stability of macromolecules in response to various environmental perturbations. Numerous proteins and macromolecular complexes have been analyzed by EPDs to summarize results from large data sets from multiple biophysical techniques. The current EPD method suffers from a number of deficiencies including lack of a meaningful relationship between color and actual molecular features, difficulties in identifying contributions from individual techniques, and a limited ability to be interpreted by color-blind individuals. In this work, three improved data visualization approaches are proposed as techniques complementary to the EPD. The secondary, tertiary, and quaternary structural changes of multiple proteins as a function of environmental stress were first measured using circular dichroism, intrinsic fluorescence spectroscopy, and static light scattering, respectively. Data sets were then visualized as (1) RGB colors using three-index EPDs, (2) equiangular polygons using radar charts, and (3) human facial features using Chernoff face diagrams. Data as a function of temperature and pH for bovine serum albumin, aldolase, and chymotrypsin as well as candidate protein vaccine antigens including a serine threonine kinase protein (SP1732) and surface antigen A (SP1650) from S. pneumoniae and hemagglutinin from an H1N1 influenza virus are used to illustrate the advantages and disadvantages of each type of data visualization technique. PMID:22898970
Histopathological lesions associated with equine periodontal disease.
Cox, Alistair; Dixon, Padraic; Smith, Sionagh
2012-12-01
Equine periodontal disease (EPD) is a common and painful condition, the aetiology and pathology of which are poorly understood. To characterise the histopathological lesions associated with EPD, the skulls of 22 horses were assessed grossly for the presence of periodontal disease, and a standard set of interdental tissues taken from each for histopathological examination. Histological features of EPD included ulceration and neutrophilic inflammation of the gingival epithelium. Mononuclear and eosinophilic inflammation of the gingival lamina propria and submucosa was commonly present irrespective of the presence or degree of periodontal disease. Gingival hyperplasia was present to some degree in all horses, and was only weakly associated with the degree of periodontal disease. In all horses dental plaque was present at the majority of sites examined and was often associated with histological evidence of peripheral cemental erosion. Bacteria (including spirochaetes in four horses) were identified in gingival samples by Gram and silver impregnation techniques and were significantly associated with the presence of periodontal disease. This is the first study to describe histological features of EPD, and the first to identify associated spirochaetes in some cases. Histological features were variable, and there was considerable overlap of some features between the normal and diseased gingiva. Further investigation into the potential role of bacteria in the pathogenesis and progression of EPD is warranted. Copyright © 2012 Elsevier Ltd. All rights reserved.
Degidi, Marco; Daprile, Giuseppe; Piattelli, Adriano
The aims of this study were to evaluate the ability of a stepped osteotomy to improve dental implant primary stability in low-density bone sites and to investigate possible correlations between primary stability parameters. The study was performed on fresh humid bovine bone classified as type III. The test group consisted of 30 Astra Tech EV implants inserted following the protocol provided by the manufacturer. The first control group consisted of 30 Astra Tech EV implants inserted in sites without the underpreparation of the apical portion. The second control group consisted of 30 Astra Tech TX implants inserted following the protocol provided by the manufacturer. Implant insertion was performed at the predetermined 30 rpm. The insertion torque data were recorded and exported as a curve; using a trapezoidal integration technique, the area underlying the curve was calculated: this area represents the variable torque work (VTW). Peak insertion torque (pIT) and resonance frequency analysis (RFA) were also recorded. A Mann-Whitney test showed that the mean VTW was significantly higher in the test group compared with the first control and second control groups; furthermore, statistical analysis showed that pIT also was significantly higher in the test group compared with the first and second control groups. Analyzing RFA values, only the difference between the test group and second control group showed statistical significance. Pearson correlation analysis showed a very strong positive correlation between pIT and VTW values in all groups; furthermore, it showed a positive correlation between pIT and RFA values and between VTW and RFA values only in the test group. Within the limitations of an in vitro study, the results show that stepped osteotomy can be a viable method to improve implant primary stability in low-density bone sites, and that, when a traditional osteotomy method is performed, RFA presents no correlation with pIT and VTW.
NASA Astrophysics Data System (ADS)
Libin, M. N.; Balasubramaniam, Krishnan; Maxfield, B. W.; Krishnamurthy, C. V.
2013-01-01
Tone Burst Eddy current Thermography (TBET) is a new hybrid, non-contacting, Non-Destructive Evaluation (NDE) method which employs a combination of Pulsed Eddy current Thermography (PEC) and Thermographic Non-Destructive Evaluation (TNDE). For understanding the influence of cracking and pitting on heat generation and flow within a metallic body, a fundamental knowledge of the detailed induced current density distribution in the component under test is required. This information enables us to calculate the amount of heat produced by the defects and how that heat diffuses to the surface where it is imaged. This paper describes simulation work done for artificial pits and cracks within pits on the far surface of poorly conducting metals like stainless steel. The first phase of this investigation simulates the transient thermal distribution for artificial 2D pit and crack-like defects using the finite element package COMSOL multi-physics with the AC/DC module and general heat transfer. Considering the reflection measurement geometry where thermal excitation and temperature monitoring are on the same surface, pitting reduces the material volume thereby contributing to a larger temperature rise for the same thermal energy input. A crack within a pit gives a further increase in temperature above the pure pit baseline. The tone burst frequency can be changed to obtain approximately uniform heating (low frequency) or heating of a thin region at the observation surface. Although front surface temperature changes due to 10% deep far-side pits in a 6 mm thick plate can be measured, it is not yet clear whether a 20% deep crack within this pit can be discriminated against the background. Both simulations and measurements will be presented. The objective of this work is to determine whether the TBET method is suitable for the detection and characterization of far side pitting, cracking and cracks within those pits.
Adopt or Adapt: Sanitation Technology Choices in Urbanizing Malawi.
Chunga, Richard M; Ensink, Jeroen H J; Jenkins, Marion W; Brown, Joe
2016-01-01
This paper presents the results of a mixed-methods study examining adaptation strategies that property owners in low-income, rapidly urbanizing areas in Malawi adopt to address the limitations of pit latrines, the most common method of disposing human excreta. A particular challenge is lack of space for constructing new latrines as population density increases: traditional practice has been to cap full pits and simply move to a new site, but increasing demands on space require new approaches to extend the service life of latrines. In this context, we collected data on sanitation technology choices from January to September 2013 through 48 in-depth interviews and a stated preference survey targeting 1,300 property owners from 27 low-income urban areas. Results showed that property owners with concern about space for replacing pit latrines were 1.8 times more likely to select pit emptying service over the construction of new pit latrines with a slab floor (p = 0.02) but there was no significant association between concern about space for replacing pit latrines and intention to adopt locally promoted, novel sanitation technology known as ecological sanitation (ecosan). Property owners preferred to adapt existing, known technology by constructing replacement pit latrines on old pit latrine locations, reducing the frequency of replacing pit latrines, or via emptying pit latrines when full. This study highlights potential challenges to adoption of wholly new sanitation technologies, even when they present clear advantages to end users. To scale, alternative sanitation technologies for rapidly urbanising cities should offer clear advantages, be affordable, be easy to use when shared among multiple households, and their design should be informed by existing adaptation strategies and local knowledge.
Adopt or Adapt: Sanitation Technology Choices in Urbanizing Malawi
Chunga, Richard M.; Ensink, Jeroen H. J.; Jenkins, Marion W.; Brown, Joe
2016-01-01
This paper presents the results of a mixed-methods study examining adaptation strategies that property owners in low-income, rapidly urbanizing areas in Malawi adopt to address the limitations of pit latrines, the most common method of disposing human excreta. A particular challenge is lack of space for constructing new latrines as population density increases: traditional practice has been to cap full pits and simply move to a new site, but increasing demands on space require new approaches to extend the service life of latrines. In this context, we collected data on sanitation technology choices from January to September 2013 through 48 in-depth interviews and a stated preference survey targeting 1,300 property owners from 27 low-income urban areas. Results showed that property owners with concern about space for replacing pit latrines were 1.8 times more likely to select pit emptying service over the construction of new pit latrines with a slab floor (p = 0.02) but there was no significant association between concern about space for replacing pit latrines and intention to adopt locally promoted, novel sanitation technology known as ecological sanitation (ecosan). Property owners preferred to adapt existing, known technology by constructing replacement pit latrines on old pit latrine locations, reducing the frequency of replacing pit latrines, or via emptying pit latrines when full. This study highlights potential challenges to adoption of wholly new sanitation technologies, even when they present clear advantages to end users. To scale, alternative sanitation technologies for rapidly urbanising cities should offer clear advantages, be affordable, be easy to use when shared among multiple households, and their design should be informed by existing adaptation strategies and local knowledge. PMID:27532871
NASA Astrophysics Data System (ADS)
Villinger, H. W.; Pichler, T.; Kaul, N.; Stephan, S.; Pälike, H.; Stephan, F.
2017-01-01
We acquired seismic and heat flow data and collected sediment cores in three areas in the Guatemala Basin (Cocos Plate, Eastern Pacific) to investigate the process by which depressions (pits) in the sedimentary cover on young oceanic crust were formed. Median heat flow of 55 mW/m2 for the three areas is about half of the expected conductive cooling value. The heat deficit is caused by massive recharge of cold seawater into the upper crust through seamounts which is inferred from depressed heat flow in the vicinity of seamounts. Heat flow inside of pits is always elevated, in some cases up to three times (max. 300 mW/m2) relative to background. None of the geochemical pore water profiles from cores inside and outside of the pits show any evidence of active fluid flow inside the pits. All three areas originated within the high productivity equatorial zone and moved northwest over the past 15 to 18 Ma. Pits found in the working areas are likely relict dissolution structures formed by diffuse hydrothermal venting in a zone of high biogenic carbonate production which were sealed when they moved north. It is likely that these pits were discharge sites of "hydrothermal siphons" where recharging seamounts could feed cold seawater via the upper crust to several discharging pits. Probably pit density on the whole Cocos Plate is similar to the three working areas and which may explain the huge heat deficit of the Cocos Plate.
Growth and dielectric properties of ZnO nanoparticles deposited by using electrophoretic deposition
NASA Astrophysics Data System (ADS)
Chung, Yoonsung; Park, Hyejin; Kim, Dong-Joo; Cho, Sung Baek; Yoon, Young Soo
2015-05-01
The deposition behavior of ZnO nanoparticles on metal plates and conductive fabrics was investigated using electrophoretic deposition (EPD). The deposition kinetics on both metal plates and fabrics were examined using the Hamaker equation. Fabric substrates give more deposited weight than flat substrates due to their rougher shape and higher surface area. The morphologies and the structures of the deposited ZnO layers showed uniform deposition without any preferred orientation on both substrates. The dielectric properties of the ZnO layers formed by using EPD showed values that were reduced, but comparable to those of bulk ZnO. This result suggests that EPD is a convenient method to deposit functional oxides on flexible substrates.
Relationship between the Foveal Avascular Zone and Foveal Pit Morphology
Dubis, Adam M.; Hansen, Benjamin R.; Cooper, Robert F.; Beringer, Joseph; Dubra, Alfredo; Carroll, Joseph
2012-01-01
Purpose. To assess the relationship between foveal pit morphology and size of the foveal avascular zone (FAZ). Methods. Forty-two subjects were recruited. Volumetric images of the macula were obtained using spectral domain optical coherence tomography. Images of the FAZ were obtained using either a modified fundus camera or an adaptive optics scanning light ophthalmoscope. Foveal pit metrics (depth, diameter, slope, volume, and area) were automatically extracted from retinal thickness data, whereas the FAZ was manually segmented by two observers to extract estimates of FAZ diameter and area. Results. Consistent with previous reports, the authors observed significant variation in foveal pit morphology. The average foveal pit volume was 0.081 mm3 (range, 0.022 to 0.190 mm3). The size of the FAZ was also highly variable between persons, with FAZ area ranging from 0.05 to 1.05 mm2 and FAZ diameter ranging from 0.20 to 1.08 mm. FAZ area was significantly correlated with foveal pit area, depth, and volume; deeper and broader foveal pits were associated with larger FAZs. Conclusions. Although these results are consistent with predictions from existing models of foveal development, more work is needed to confirm the developmental link between the size of the FAZ and the degree of foveal pit excavation. In addition, more work is needed to understand the relationship between these and other anatomic features of the human foveal region, including peak cone density, rod-free zone diameter, and Henle fiber layer. PMID:22323466
Contract Training and Computer-Assisted Instruction at Santa Fe Community College.
ERIC Educational Resources Information Center
Ortego, Sheila; Richards, Beverly
In summer 1993, Santa Fe Community College, New Mexico, created the External Programs Division (EPD) under its credit instruction program to serve the needs of non-traditional students. The EPD encompasses contract training, the Flex Lab, distance education, the AutoDesk Training Center, an Alternative Fuels program, and the corrections training…
Life-Cycle Inventory Analysis of Cellulosic Fiberboard Production in North America
Richard D. Bergman
2014-01-01
Documenting the environmental performance of building products is becoming widespread because of many green-marketing claims made without scientific merit (i.e., green-washing). Developing environmental product declarations (EPDs) for building products is one way to accomplish this objective for scientific documentation and to counter green-washing. EPDs are based on...
Developing a Web-Based Mechanism for Assessing Teacher Science Content Knowledge
ERIC Educational Resources Information Center
Byers, Al; Koba, Susan; Sherman, Greg; Scheppke, Joan; Bolus, Roger
2011-01-01
The National Science Teachers Association (NSTA) recently launched a comprehensive electronic professional development (e-PD) online portal, the NSTA Learning Center. This support site for educators currently includes over 6,000 e-PD resources and opportunities available on-demand, as well as various tools designed to help educators maximize the…
Evaluation of Educational Personnel Development Projects in Indian Education. Final Report.
ERIC Educational Resources Information Center
Wechsler, Marjorie E.; And Others
The Educational Personnel Development (EPD) program provides training for educational personnel to serve American Indian and Alaska Native students. From FY 1987 to FY 1991, EPD grants averaging $2.25 million per year were awarded to 21 institutions, which provided academic counseling, direct financial assistance, and supplemental training to a…
Adouard, F; Glangeaud-Freudenthal, N M C; Golse, B
2005-06-01
This research is intended to validate the Edinburgh Postnatal Depression Scale (EPDS) in a high-risk pregnant population. Sixty women attending antenatal consultations for pregnancy complication in a major Parisian maternity facility were included. They completed the EPDS and were then interviewed according to a standardised psychiatric interview. The study of its sensitivity, specificity and predictive values, with a DSM-IV diagnosis of major depression as the reference, found that 11.5 was the optimal cut-off score (Se 0.80; Sp 0.80). Its validity as an index of severity of depression was also good as well as internal consistency and reliability. Factor analysis showed that its internal structure is composed of two subscales (F2 "depression" and F1 with items reflecting depression and other disorders, including anxiety). The French version of the EPDS would be a valid instrument to identify pregnant women who are likely to have clinical major depression. The results may have to be confirmed on a community sample before clinical use.
NASA Astrophysics Data System (ADS)
Goudarzi, Mona; Batmanghelich, Farhad; Afshar, Abdollah; Dolati, Abolghasem; Mortazavi, Golsa
2014-05-01
Hydroxyapatite (HA) coatings in and onto anodized TiO2 nanotube arrays were presented and prepared by electrophoretic deposition technique (EPD). Coatings were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). EPD proved to be an innovative and versatile technique to coat HA on and into nanotubular structures of TiO2 with enhanced adhesion between nanotubes and HA particles provided by mechanical interlocking. After EPD of HA on TiO2 layer, samples were sintered at 400 °C, 600 °C and 800 °C for 2 h in an Ar atmosphere. Effect of EPD processing parameters on thickness of the deposits and rate of deposition was elucidated for HA coatings on the nanotubular TiO2 structures. It was shown that higher applied voltages increase deposition rate and thickness of the coatings. Potentiodynamic polarization measurements proved corrosion protection caused by both HA coating and nanotubular TiO2 structure in simulated body fluid (SBF). Effect of sintering temperature on adhesion strength of HA coatings on TiO2 nanotubes and their composition were also studied.
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. The IOA product for the EPD and C analysis consisted of 1671 failure mode analysis worksheets that resulted in 468 potential critical items being identified. Comparison was made to the proposed NASA Post 51-L baseline which consisted of FMEAs and 158 CIL items. Volume 1 contains the EPD and C subsystem description, analysis results, ground rules and assumptions, and some of the IOA worksheets.
Jain, Akanksha; Tyagi, Prashant; Kaur, Prabhjeet; Puliyel, Jacob; Sreenivas, Vishnu
2014-01-01
Objectives and hypothesis To examine the influence of gender of the baby on exclusive breastfeeding and incidence of postnatal depression (PND). We hypothesise that in a society with a male gender bias there may be more PND and less exclusive breastfeeding of the girl child. Design Prospective study. Setting The study was conducted in an urban, tertiary hospital in Delhi. Participants Mothers delivering normally with their babies roomed-in.1537 eligible women participated in the study. Primary and secondary outcome measures Exclusive breastfeeding within the first 48 h of life and score on the Edinburgh Postnatal Depression Scale (EPDS) were recorded. Results 3466 babies were born in the hospital. There were 792 girls for every 1000 boys. Among primiparous women, the sex ratio was 901 girls per 1000 boys. For second babies, the sex ratio was 737:1000. If the first child was a girl the birth ratio fell to 632. 1026 mothers were exclusively breastfeeding. Exclusive breastfeeding of boys was significantly higher (70.8% vs 61.5%, p<0.001). The EPDS score was significantly higher with the birth of girls (EPDS 6.0±3.39 vs 5.4±2.87, p<0.01). Women with an EPDS score >11 were less likely to exclusively breastfeed (p<0.01). Conclusions The results point to a pro-male gender bias evidenced by a low sex ratio at birth, higher EPDS score in mothers of girls and less breastfeeding of female children. PMID:24913326
Byatt, Nancy; Moore Simas, Tiffany A; Biebel, Kathleen; Sankaran, Padma; Pbert, Lori; Weinreb, Linda; Ziedonis, Douglas; Allison, Jeroan
2017-10-10
This pilot study was designed to inform a larger effectiveness trial by: (1) assessing the feasibility of the PRogram In Support of Moms (PRISM) and our study procedures; and, (2) determining the extent to which PRISM as compared to an active comparison group, the Massachusetts Child Access Psychiatry Program (MCPAP) for Moms alone, improves depression among perinatal women. Four practices were randomized to either PRISM or MCPAP for Moms alone, a state-wide telephonic perinatal psychiatry program. PRISM includes MCPAP for Moms plus implementation assistance with local champions, training, and implementation of office prompts and procedures to enhance depression screening, assessment and treatment. Patients with Edinburgh Postnatal Depression Scales (EPDS) ≥ 10 were recruited during pregnancy, and completed the EPDS and a structured interview at baseline and 3-12 weeks' postpartum. Among MCPAP for Moms alone practices, patients' (n = 9) EPDS scores improved from 15.22 to 10.11 (p = 0.010), whereas in PRISM practices patients' (n = 21) EPDS scores improved from 13.57 to 6.19 (p = 0.001); the between groups difference-of-differences was 2.27 (p = 0.341). PRISM was beneficial for patients, clinicians, and support staff. Both PRISM and MCPAP for Moms alone improve depression symptom severity and the percentage of women with an EPDS >10. The improvement difference between groups was not statistically significant due to limited power associated with small sample size.
Inconsolable infant crying and maternal postpartum depressive symptoms.
Radesky, Jenny S; Zuckerman, Barry; Silverstein, Michael; Rivara, Frederick P; Barr, Marilyn; Taylor, James A; Lengua, Liliana J; Barr, Ronald G
2013-06-01
To quantify the extent to which maternal report of inconsolable infant crying, rather than colic (defined by Wessel's criteria of daily duration of fussing and crying >3 hours), is associated with maternal postpartum depressive symptoms. Participants were 587 mothers who were recruited shortly before or after delivery and followed longitudinally. At 5 to 6 weeks postpartum, mothers recorded the duration and mode (fussing, crying, or inconsolable crying) of their infant's distress by using the Baby's Day Diary. The Edinburgh Postnatal Depression Scale (EPDS) was administered at enrollment and at 8 weeks postpartum. Using regression models that included baseline EPDS scores and multiple confounders, we examined associations of colic and inconsolable crying with later maternal EPDS scores at 8 weeks postpartum. Sixty mothers (10%) met the EPDS threshold for "possible depression" (score ≥9) at 8 weeks postpartum. For mothers reporting >20 minutes of inconsolable crying per day, the adjusted odds ratio for an EPDS score ≥9 was 4.0 (95% confidence interval: 2.0-8.1), whereas the adjusted odds ratio for possible depression in mothers whose infants had colic was 2.0 (95% confidence interval: 1.1-3.7). These associations persisted after adjusting for baseline depression symptoms. Maternal report of inconsolable infant crying may have a stronger association with postpartum depressive symptoms than infant colic. Asking a mother about her ability to soothe her infant may be more relevant for potential intervention than questions about crying and fussing duration alone.
Uguz, Faruk; Akman, Cemal; Sahingoz, Mine; Kaya, Nazmiye; Kucur, Rahim
2009-06-01
Long-term follow-up and risk factors of persistent post-partum depression (PPD) are fairly unknown compared with its prevalence in the developing countries. In this study, we did a follow-up measure of PPD and examined the factors, which were associated with PPD 1-year post-partum. Our sample comprised of 34 women. Depressive symptoms were assessed by the Edinburgh post-natal depression scale (EPDS) 6 weeks post-partum, and women with scores >12 on this scale was categorised as depressed. Personality disorders were determined at the same occasion by means of the Structured Clinical Interview for DSM-III-R personality disorders (SCID-II). One year post-partum EPDS was completed. The rate of PPD 1-year post-partum was 32.4%, and it was unrelated to age at assessment, primiparity, number of children, employment status, economical status and educational level. Women depressed 1-year post-partum had significantly higher basal scores of EPDS and more often also a diagnosis of any axis II disorder; and specifically dependent and obsessive-compulsive personality disorders. In our sample, the predictors of 1-year post-partum PPD were having higher basal score of EPDS and the existence of a personality disorder. This study suggests that women with PPD, scoring high in the EPDS scale 6 weeks post-partum and having a personality disorder, run a higher risk for depression at 1-year follow-up.
Stewart, Robert C; Umar, Eric; Tomenson, Barbara; Creed, Francis
2013-09-25
The detection of antenatal depression in resource-limited settings such as Malawi, Africa, is important and requires an accurate and practical screening tool. It is not known which questionnaire would be most suitable for this purpose. A rigorously translated and modified Chichewa version of the Edinburgh Postnatal Depression Scale (EPDS) was developed. The Chichewa EPDS and an existing Chichewa version of the Self Reporting Questionnaire (SRQ) were validated in women attending an antenatal clinic in rural Malawi, using DSM-IV major and major-or-minor depressive episode as the gold standard diagnoses, determined with Structured Clinical Interview for DSM-IV (SCID). Weighted test characteristics for each possible cut-off were calculated and Receiver Operator Characteristic (ROC) curves derived. The participants were 224 pregnant women, 92 of whom were interviewed using the SCID. The area under the ROC curve (AUC) for detection of current major depressive disorder for the EPDS was 0.811 (95% CI 0.734-0.889) and for the SRQ was 0.833 (95% CI 0.770-0.897). AUC for major-or-minor depressive disorder for the EPDS was 0.767 (95% CI 0.695-0.839) and for the SRQ was 0.883 (95% CI 0.839-0.927). These were not significant differences. Internal consistency was high for both the SRQ (Cronbach's alpha 0.825) and the EPDS (Cronbach's alpha 0.904). Inter-rater reliability testing was not done. The relatively small sample size resulted in wide confidence intervals around AUCs. The study was conducted amongst antenatal clinic attenders only, limiting generalisability to all pregnant women in this setting. The Chichewa versions of the EPDS and SRQ both show utility as brief screening measures for detection of antenatal depression in rural Malawi. © 2013 Elsevier B.V. All rights reserved.
Austin, Marie-Paule V; Hadzi-Pavlovic, Dusan; Priest, Susan R; Reilly, Nicole; Wilhelm, Kay; Saint, Karen; Parker, Gordon
2010-10-01
The objectives of this study were: (1) to examine Composite International Diagnostic Interview (CIDI) period prevalence and comorbidity for depression and anxiety disorder in a cohort of women assessed during the first 6-8 months postpartum and (2) to examine the benefits of combining the Edinburgh Postnatal Depression Scale (EPDS) with a simple "interval symptom" question to optimize screening postpartum. Women aged over 18 (N = 1,549) were assessed during late pregnancy and reviewed at approximately 2, 4, and 6-8 months postpartum using the EPDS and an "interval symptom" question. The latter asked about any depressive symptoms in the interval since the last EPDS. Women who scored >12 on the EPDS and/or positive on the "interval symptom" question were then administered the CIDI. A further 65 randomly selected women that screened negative were also administered the CIDI. Loss to postnatal follow-up was very significant, and returns rates were inconsistent across the three postnatal time points. Almost 25% of those who screened positive did not complete a CIDI. For screen-positive status, a total of 314 (24.4%) of those that returned questionnaires (N = 1,289) screened positive at least once across the 6- to 8-month interval. Of these, 79 were lost to follow-up; thus, 235 (74.8%) completed a CIDI. In this group, 34.7% had been positive both on the EPDS and the "interval" question, 15.9% on the EPDS alone, and 49.4% on the "interval" question alone. For the CIDI diagnosis and estimated 6- to 8-month period CIDI prevalence, among those 235 women who screened positive and completed a CIDI, 67.2% met the criteria for a CIDI diagnosis, as did 16.9% of those who screened negative. The breakdown in CIDI diagnoses in the 235 women was 32.8% major depression (± anxiety disorder); 26.4% minor depression alone; and 8.1% with a primary anxiety disorder (approximately half with minor depression). Put another way, 20.4% of these women had an anxiety disorder (approximately two thirds with comorbid depression) and 37.7% of women with a major depressive episode (MDE) had a comorbid anxiety disorder. The estimated 6- to 8-month prevalence rate for a CIDI diagnosis of anxiety or depression (major or minor) was 29.2% (95% CI 26.7%-31.7%). The use of the "interval symptom" question alone was 1.7 times more likely to identify positive CIDI cases than the EPDS alone. Almost 40% of postnatal women with a diagnosis of MDE have a comorbid diagnosis of anxiety disorder. The estimated 6- to 8-month period prevalence for CIDI cases of anxiety and depression was 29.2%. Screening for anxiety and depression using the EPDS alone was associated with a lesser capacity to identify CIDI caseness than a simple "interval symptom" question (for the 2 months prior) which almost doubled the yield. This paper demonstrates that combining the EPDS with the "interval symptom" question improves detection of CIDI caseness.
Gibeaut, David M; Whiting, Matthew D; Einhorn, Todd
2017-02-01
The archetypical double sigmoid-shaped growth curve of the sweet cherry drupe (Prunus avium) does not address critical development from eco-dormancy to anthesis and has not been correlated to reproductive bud development. Accurate representation of the growth and development of post-anthesis ovaries is confounded by anthesis timing, fruiting-density and the presence of unfertilized and defective ovaries whose growth differs from those that persist to maturation. These factors were addressed to assess pre-anthesis and full-season growth and development of three sweet cherry cultivars, 'Chelan', 'Bing' and 'Sweetheart', differing primarily in seasonal duration and fruit size. Volume was calculated from photographic measurements of reproductive buds, ovaries and pits at all phases of development. A population of unfertilized ovaries was produced using bee-exclusion netting to enable a statistical comparison with an open pollinated population to detect differences in size and shape between successful and failing fruit growth. Anthesis timing and fruiting-density were manipulated by floral extinction at the spur and whole-tree scales. Developmental time indices were analysed using polynomial curve fitting of log-transformed data supported by Richards and logistic functions of asymptotic growth of the pit and maturing fruit, respectively. Pre-anthesis growth began at the completion of eco-dormancy. A slight decline in relative growth rate (RGR) was observed during bud scale separation approx. -16 d from anthesis (DFA) before resumption of exponential growth to a maximum about 14 DFA. After anthesis, reduced growth of unfertilized or defective ovaries was partly discriminated from successful fruit at 5 DFA and completely at 25 DFA. Time indices of RGR inflections were similar among cultivars when adjusted for anthesis date alone, until the end of pit growth. Asymptotic growth of the pit underpinned the declining growth rate of fruit at the end of the first exponential growth phase. Duration of the subsequent expansive growth phase accounted for genotypic differences in seasonal duration and final size. Pit size and final fruit size were inversely related to fruiting-density. Developmental differences among early, mid and late maturing cultivars were not detected until the final growth period. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Gibeaut, David M.; Whiting, Matthew D.; Einhorn, Todd
2017-01-01
Background and Aims The archetypical double sigmoid-shaped growth curve of the sweet cherry drupe (Prunus avium) does not address critical development from eco-dormancy to anthesis and has not been correlated to reproductive bud development. Accurate representation of the growth and development of post-anthesis ovaries is confounded by anthesis timing, fruiting-density and the presence of unfertilized and defective ovaries whose growth differs from those that persist to maturation. These factors were addressed to assess pre-anthesis and full-season growth and development of three sweet cherry cultivars, ‘Chelan’, ‘Bing’ and ‘Sweetheart’, differing primarily in seasonal duration and fruit size. Methods Volume was calculated from photographic measurements of reproductive buds, ovaries and pits at all phases of development. A population of unfertilized ovaries was produced using bee-exclusion netting to enable a statistical comparison with an open pollinated population to detect differences in size and shape between successful and failing fruit growth. Anthesis timing and fruiting-density were manipulated by floral extinction at the spur and whole-tree scales. Developmental time indices were analysed using polynomial curve fitting of log-transformed data supported by Richards and logistic functions of asymptotic growth of the pit and maturing fruit, respectively. Key Results Pre-anthesis growth began at the completion of eco-dormancy. A slight decline in relative growth rate (RGR) was observed during bud scale separation approx. −16 d from anthesis (DFA) before resumption of exponential growth to a maximum about 14 DFA. After anthesis, reduced growth of unfertilized or defective ovaries was partly discriminated from successful fruit at 5 DFA and completely at 25 DFA. Time indices of RGR inflections were similar among cultivars when adjusted for anthesis date alone, until the end of pit growth. Asymptotic growth of the pit underpinned the declining growth rate of fruit at the end of the first exponential growth phase. Duration of the subsequent expansive growth phase accounted for genotypic differences in seasonal duration and final size. Pit size and final fruit size were inversely related to fruiting-density. Conclusions Developmental differences among early, mid and late maturing cultivars were not detected until the final growth period. PMID:28064193
Dependency of EBT2 film calibration curve on postirradiation time
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chang, Liyun, E-mail: liyunc@isu.edu.tw; Ding, Hueisch-Jy; Ho, Sheng-Yow
2014-02-15
Purpose: The Ashland Inc. product EBT2 film model is a widely used quality assurance tool, especially for verification of 2-dimensional dose distributions. In general, the calibration film and the dose measurement film are irradiated, scanned, and calibrated at the same postirradiation time (PIT), 1-2 days after the films are irradiated. However, for a busy clinic or in some special situations, the PIT for the dose measurement film may be different from that of the calibration film. In this case, the measured dose will be incorrect. This paper proposed a film calibration method that includes the effect of PIT. Methods: Themore » dose versus film optical density was fitted to a power function with three parameters. One of these parameters was PIT dependent, while the other two were found to be almost constant with a standard deviation of the mean less than 4%. The PIT-dependent parameter was fitted to another power function of PIT. The EBT2 film model was calibrated using the PDD method with 14 different PITs ranging from 1 h to 2 months. Ten of the fourteen PITs were used for finding the fitting parameters, and the other four were used for testing the model. Results: The verification test shows that the differences between the delivered doses and the film doses calculated with this modeling were mainly within 2% for delivered doses above 60 cGy, and the total uncertainties were generally under 5%. The errors and total uncertainties of film dose calculation were independent of the PIT using the proposed calibration procedure. However, the fitting uncertainty increased with decreasing dose or PIT, but stayed below 1.3% for this study. Conclusions: The EBT2 film dose can be modeled as a function of PIT. For the ease of routine calibration, five PITs were suggested to be used. It is recommended that two PITs be located in the fast developing period (1∼6 h), one in 1 ∼ 2 days, one around a week, and one around a month.« less
Modeling pitting corrosion of iron exposed to alkaline solutions containing nitrate and nitrite
NASA Astrophysics Data System (ADS)
Chen, Lifeng
2001-07-01
Pitting corrosion could be extremely serious for dilute high-level radioactive waste stored or processed in carbon steel tanks at the Savannah River Site. In these solutions, nitrate is an aggressive ion with respect to pitting of carbon steel while nitrite can be used as an inhibitor. Excessive additions of nitrite increase the risk of generating unstable nitrogen compounds during waste processing, and insufficient additions of nitrite could increase the risk of corrosion-induced failure. Thus there are strong incentives to obtain a fundamental understanding of the role of nitrite in pitting corrosion prevention with these solution chemistries. In this dissertation, both a 1-D and a 2-D model are used to study the pitting mechanism as a function of nitrite/nitrate ratios. The 1-D model used BAND(J) to test a reaction mechanism for the passivation behavior by comparing the predicted Open Circuit Potential (OCP) with OCP data from experiments at different NO2-/NO3- ratio. The model predictions are compared with Cyclic Potentiodynamic Polarization (CPP) experiments. A 2-D model was developed for the propagation of a pit in iron by writing subroutines for finite element software of GAMBIT and FIDAP. Geometrically distributed anodic and cathodic reactions are assumed. The results show three partial explanations describing the inhibition influence of nitrite to iron corrosion: the competing reduction reaction of nitrate to nitrite, the formation of Fe(OH)+, and the function of the porous film. The current distributions and the effect of porosity of the film on pH are also explained. The calculation results also show that rate of pit growth decreases as the pit diameter increases until it reaches a constant value. The profile of the local current density on the pit wall is parabolic for small pits and it changes to a linear distribution for large pits. The model predicts that addition of nitrite will decrease the production of ferrous ions and those can prevent iron from dissolving. Also nitrate ion will accumulate in the pit if not enough inhibitor is added to the solution, and this will accelerate pit growth.
Richard Bergman; Adam Taylor
2011-01-01
Transparent and credible environmental labeling of products is vital for a sustainable future. Ecolabeling shows information on the environmental performance of products, processes, and services. This article focuses on one type of ecolabeling referred to as environmental product declarations (EPDs) that provide environmental impact information based on life cycle...
The Savannah River Site`s Groundwater Monitoring Program. Second quarter, 1991
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-01-10
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site`s (SRS) Groundwater Monitoring Program. During second quarter 1991 EPD/EMS conducted extensive sampling of monitoring wells. EPD/EMS established two sets of flagging criteria in 1986 to assist in the management of sample results. The flagging criteria do not define contamination levels; instead, they aid personnel in sample scheduling, interpretation of data, and trend identification. Beginning in 1991, the flagging criteria are based on EPA drinking water standards and method detection limits. A detailed explanation of the current flagging criteria is presented in the Flagging Criteria section of this document.more » Analytical results from second quarter 1991 are listed in this report.« less
The Savannah River Site's Groundwater Monitoring Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-01-10
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site's (SRS) Groundwater Monitoring Program. During second quarter 1991 EPD/EMS conducted extensive sampling of monitoring wells. EPD/EMS established two sets of flagging criteria in 1986 to assist in the management of sample results. The flagging criteria do not define contamination levels; instead, they aid personnel in sample scheduling, interpretation of data, and trend identification. Beginning in 1991, the flagging criteria are based on EPA drinking water standards and method detection limits. A detailed explanation of the current flagging criteria is presented in the Flagging Criteria section of this document.more » Analytical results from second quarter 1991 are listed in this report.« less
Independent Orbiter Assessment (IOA): Assessment of the EPD and C/remote manipulator system FMEA/CIL
NASA Technical Reports Server (NTRS)
Robinson, W. W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Distribution and Control (EPD and C)/Remote Manipulator System (RMS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA analysis of the EPD and C/RMS hardware initially generated 345 failure mode worksheets and identified 117 Potential Critical Items (PCIs) before starting the assessment process. These analysis results were compared to the proposed NASA Post 51-L baseline of 132 FMEAs and 66 CIL items.
The Savannah River Site's Groundwater Monitoring Program: Second quarter 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, C.D.
1992-10-07
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site's (SRS) Groundwater Monitoring Program. During second quarter 1992, EPD/EMS conducted extensive sampling of monitoring wells. EPD/EMS established two sets of criteria to assist in the management of sample results. The flagging criteria do not define contamination levels; instead, they aid personnel in sample scheduling, interpretation of data, and trend identification. Since 1991, the flagging criteria have been based on the federal Environmental Protection Agency (EPA) drinking water standards and on method detection limits. A detailed explanation of the current flagging criteria is presented in the Flagging Criteria sectionmore » of this document. Analytical results from second quarter 1992 are listed in this report.« less
Kweka, Eliningaya J; Mahande, Aneth M
2009-07-06
Adult malaria vector sampling is the most important parameter for setting up an intervention and understanding disease dynamics in malaria endemic areas. The intervention will ideally be species-specific according to sampling output. It was the objective of this study to evaluate four sampling techniques, namely human landing catch, pit shelter, indoor resting collection and odour-baited entry trap. These four sampling methods were evaluated simultaneously for thirty days during October 2008, a season of low mosquitoes density and malaria transmission. These trapping methods were performed in one village for maximizing homogeneity in mosquito density. The cattle and man used in odour-baited entry trap were rotated between the chambers to avoid bias. A total of 3,074 mosquitoes were collected. Among these 1,780 (57.9%) were Anopheles arabiensis and 1,294 (42.1%) were Culex quinquefasciatus. Each trap sampled different number of mosquitoes, Indoor resting collection collected 335 (10.9%), Odour-baited entry trap-cow 1,404 (45.7%), Odour-baited entry trap-human 378 (12.3%), Pit shelter 562 (18.3%) and HLC 395 (12.8%). General linear model univariate analysis method was used, position of the trapping method had no effect on mosquito density catch (DF = 4, F = 35.596, P = 0.78). Days variation had no effect on the collected density too (DF = 29, F = 4.789, P = 0.09). The sampling techniques had significant impact on the caught mosquito densities (DF = 4, F = 34.636, P < 0.0001). The Wilcoxon pair-wise comparison between mosquitoes collected in human landing catch and pit shelter was significant (Z = -3.849, P < 0.0001), human landing catch versus Indoor resting collection was not significant (Z = -0.502, P = 0.615), human landing catch versus odour-baited entry trap-man was significant (Z = -2.687, P = 0.007), human landing catch versus odour-baited entry trap-cow was significant (Z = -3.127, P = 0.002). Odour-baited traps with different baits and pit shelter have shown high productivity in collecting higher densities of mosquitoes than human landing catch. These abilities are the possibilities of replacing the human landing catch practices for sampling malaria vectors in areas with An. arabiensis as malaria vectors. Further evaluations of these sampling methods need to be investigated is other areas with different species.
Thermo-Chemical Convection in Europa's Icy Shell with Salinity
NASA Technical Reports Server (NTRS)
Han, L.; Showman, A. P.
2005-01-01
Europa's icy surface displays numerous pits, uplifts, and chaos terrains that have been suggested to result from solid-state thermal convection in the ice shell, perhaps aided by partial melting. However, numerical simulations of thermal convection show that plumes have insufficient buoyancy to produce surface deformation. Here we present numerical simulations of thermochemical convection to test the hypothesis that convection with salinity can produce Europa's pits and domes. Our simulations show that domes (200-300 m) and pits (300-400 m) comparable to the observations can be produced in an ice shell of 15 km thick with 5-10% compositional density variation if the maximum viscosity is less than 10(exp 18) Pa sec. Additional information is included in the original extended abstract.
Reduction of Defects in Germanium-Silicon
NASA Technical Reports Server (NTRS)
2003-01-01
Crystals grown without contact with a container have far superior quality to otherwise similar crystals grown in direct contact with a container. In addition to float-zone processing, detached- Bridgman growth is a promising tool to improve crystal quality, without the limitations of float zoning or the defects introduced by normal Bridgman growth. Goals of this project include the development of the detached Bridgman process to be reproducible and well understood and to quantitatively compare the defect and impurity levels in crystals grown by these three methods. Germanium (Ge) and germanium-silicon (Ge-Si) alloys are being used. At MSFC, we are responsible for the detached Bridgman experiments intended to differentiate among proposed mechanisms of detachment, and to confirm or refine our understanding of detachment. Because the contact angle is critical to determining the conditions for detachment, the sessile drop method was used to measure the contact angles as a function of temperature and composition for a large number of substrates made of potential ampoule materials. Growth experiments have used pyrolytic boron nitride (pBN) and fused silica ampoules with the majority of the detached results occurring predictably in the pBN. Etch pit density (EPD) measurements of normal and detached Bridgman-grown Ge samples show a two order of magnitude improvement in the detached-grown samples. The nature and extent of detachment is determined by using profilometry in conjunction with optical and electron microscopy. The stability of detachment has been analyzed, and an empirical model for the conditions necessary to achieve sufficient stability to maintain detached growth for extended periods has been developed. We have investigated the effects on detachment of ampoule material, pressure difference above and below the melt, and Si concentration; samples that are nearly completely detached can be grown repeatedly in pBN. Current work is concentrated on developing a method to make in situ pressure measurements in the growth ampoules.
The “Puck” energetic charged particle detector: Design, heritage, and advancements
Cohen, I.; Westlake, J. H.; Andrews, G. B.; Brandt, P.; Gold, R. E.; Gkioulidou, M. A.; Hacala, R.; Haggerty, D.; Hill, M. E.; Ho, G. C.; Jaskulek, S. E.; Kollmann, P.; Mauk, B. H.; McNutt, R. L.; Mitchell, D. G.; Nelson, K. S.; Paranicas, C.; Paschalidis, N.; Schlemm, C. E.
2016-01-01
Abstract Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low‐resource missions in the past, the need was recognized for a low‐resource but highly capable, mass‐species‐discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the “Puck” EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high‐voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions. PMID:27867799
The "Puck" energetic charged particle detector: Design, heritage, and advancements.
Clark, G; Cohen, I; Westlake, J H; Andrews, G B; Brandt, P; Gold, R E; Gkioulidou, M A; Hacala, R; Haggerty, D; Hill, M E; Ho, G C; Jaskulek, S E; Kollmann, P; Mauk, B H; McNutt, R L; Mitchell, D G; Nelson, K S; Paranicas, C; Paschalidis, N; Schlemm, C E
2016-08-01
Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of ~10 keV to several MeV. This sensor makes simultaneous angular measurements of electron fluxes from the tens of keV to about 1 MeV. The same measurements can be extended down to approximately 1 keV/nucleon, with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.
The "Puck" Energetic Charged Particle Detector: Design, Heritage, and Advancements
NASA Technical Reports Server (NTRS)
Clark, G.; Cohen, I.; Westlake, J. H.; Andrews, G. B.; Brandt, P.; Gold, R. E.; Gkioulidou, M. A.; Hacala, R.; Haggerty, D.; Hill, M. E.;
2016-01-01
Energetic charged particle detectors characterize a portion of the plasma distribution function that plays critical roles in some physical processes, from carrying the currents in planetary ring currents to weathering the surfaces of planetary objects. For several low-resource missions in the past, the need was recognized for a low-resource but highly capable, mass-species-discriminating energetic particle sensor that could also obtain angular distributions without motors or mechanical articulation. This need led to the development of a compact Energetic Particle Detector (EPD), known as the "Puck" EPD (short for hockey puck), that is capable of determining the flux, angular distribution, and composition of incident ions between an energy range of approximately 10 kiloelectronvolts to several megaelectronvolts. This sensor makes simultaneous angular measurements of electron fluxes from the tens of kiloelectronvolts to about 1 megaelectronvolt. The same measurements can be extended down to approximately 1 kiloelectronvolt per nucleon,with some composition ambiguity. These sensors have a proven flight heritage record that includes missions such as MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) and New Horizons, with multiple sensors on each of Juno, Van Allen Probes, and Magnetospheric Multiscale. In this review paper we discuss the Puck EPD design, its heritage, unexpected results from these past missions and future advancements. We also discuss high-voltage anomalies that are thought to be associated with the use of curved foils, which is a new foil manufacturing processes utilized on recent Puck EPD designs. Finally, we discuss the important role Puck EPDs can potentially play in upcoming missions.
Lebel, Catherine; Walton, Matthew; Letourneau, Nicole; Giesbrecht, Gerald F; Kaplan, Bonnie J; Dewey, Deborah
2016-12-01
Perinatal maternal depression is a serious health concern with potential lasting negative consequences for children. Prenatal depression is associated with altered brain gray matter in children, though relations between postpartum depression and children's brains and the role of white matter are unclear. We studied 52 women who provided Edinburgh Postnatal Depression Scale (EPDS) scores during each trimester of pregnancy and at 3 months postpartum and their children who underwent magnetic resonance imaging at age 2.6 to 5.1 years. Associations between maternal depressive symptoms and magnetic resonance imaging measures of cortical thickness and white matter structure in the children were investigated. Women's second trimester EPDS scores negatively correlated with children's cortical thickness in right inferior frontal and middle temporal regions and with radial and mean diffusivity in white matter emanating from the inferior frontal area. Cortical thickness, but not diffusivity, correlations survived correction for postpartum EPDS. Postpartum EPDS scores negatively correlated with children's right superior frontal cortical thickness and with diffusivity in white matter originating from that region, even after correcting for prenatal EPDS. Higher maternal depressive symptoms prenatally and postpartum are associated with altered gray matter structure in children; the observed white matter correlations appear to be uniquely related to the postpartum period. The reduced thickness and diffusivity suggest premature brain development in children exposed to higher maternal perinatal depressive symptoms. These results highlight the importance of ensuring optimal women's mental health throughout the perinatal period, because maternal depressive symptoms appear to increase children's vulnerability to nonoptimal brain development. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
McIntyre, Joanna; Hobson, Andrew J.; Mitchell, Nick
2009-01-01
This article discusses the evaluation of a unique university-based early professional development (EPD) programme in England that enabled newly and recently qualified teachers to have continued contact with their initial teacher preparation provider. The programme was designed to enhance the induction, EPD and retention of beginning teachers of…
The Galileo Energetic Particles Detector
NASA Technical Reports Server (NTRS)
Williams, D. J.; Mcentire, R. W.; Jaskulek, S.; Wilken, B.
1992-01-01
Amongst its complement of particles and fields instruments, the Galileo spacecraft carries an Energetic Particles Detector (EPD) designed to measure the characteristics of particle populations important in determining the size, shape, and dynamics of the Jovian magnetosphere. To do this the EPD provides 4pi angular coverage and spectral measurements for Z greater than or equal to 1 ions from 20 keV to 55 MeV, for electrons from 15 keV to greater than 11 MeV, and for the elemental species helium through iron from approximately 10 keV/nucl to 15 MeV/nucl. Two bidirectional telescopes, mounted on a stepping platform, employ magnetic deflection, energy loss versus energy, and time-of-flight techniques to provide 64 rate channels and pulse height analysis of priority selected events. The EPD data system provides a large number of possible operational modes from which a small number will be selected to optimize data collection during the many encounter and cruise phases of the mission. The EPD employs a number of safeing algorithms that are to be used in the event that its self-checking procedures indicate a problem. The instrument and its operation are described.
Relationship between anemia and depressive mood in the last trimester of pregnancy.
Yılmaz, Elif; Yılmaz, Zehra; Çakmak, Bülent; Gültekin, İsmail Burak; Çekmez, Yasemin; Mahmutoğlu, Selma; Küçüközkan, Tuncay
2017-04-01
To compare the relationship between the severity of anemia and depressive mood in the last trimester of pregnancy. A cross-sectional study, enrolled a total of 450 pregnant women who attended the antenatal clinics in their third trimester for their routine antenatal follow-up. Depressive symptoms were assessed by the Edinburgh Postnatal Depression Scale. The study group was divided into two groups according to presence of anemia; anemic group (Hb < 11 gr/L; n = 150) and non-anemic group (Hb ≥ 11 gr/L; n = 300) and depression scores were compared. One hundred and fourteen (25.3%) women scored ≥13 points which were considered the cutoff value for depression on the EPDS. Anemia frequency was found as 33.3%. The total EPDS score was significantly higher in the anemic group (EPDS score 11 [min-max 0-29]) compared with the non-anemic group (EPDS score 7 [min-max 0-21]) (p = 0.000). Multiple regression analysis also revealed that serum Hb level was an independent factor for antenatal depressive mood. As anemia is associated with higher depressive symptom levels, it should be carefully considered during pregnancy. Prospective studies are needed to confirm our results.
NASA Technical Reports Server (NTRS)
Patton, Jeff A.
1986-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Distribution and Control (EPD and C)/Electrical Power Generation (EPG) hardware. The EPD and C/EPG hardware is required for performing critical functions of cryogenic reactant storage, electrical power generation and product water distribution in the Orbiter. Specifically, the EPD and C/EPG hardware consists of the following components: Power Section Assembly (PSA); Reactant Control Subsystem (RCS); Thermal Control Subsystem (TCS); Water Removal Subsystem (WRS); and Power Reactant Storage and Distribution System (PRSDS). The IOA analysis process utilized available EPD and C/EPG hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.
Chen, Qiang; Jing, Jiajia; Qi, Hongfei; Ahmed, Ifty; Yang, Haiou; Liu, Xianhu; Lu, T L; Boccaccini, Aldo R
2018-04-11
Structural and compositional modifications of metallic implant surfaces are being actively investigated to achieve improved bone-to-implant bonding. In this study, a strategy to modify bulk metallic surfaces by electrophoretic deposition (EPD) of short phosphate glass fibers (sPGF) is presented. Random and aligned orientation of sPGF embedded in a poly(acrylic acid) matrix is achieved by vertical and horizontal EPD, respectively. The influence of EPD parameters on the degree of alignment is investigated to pave the way for the fabrication of highly aligned sPGF structures in large areas. Importantly, the oriented sPGF structure in the coating, owing to the synergistic effects of bioactive composition and fiber orientation, plays an important role in directional cell migration and enhanced proliferation. Moreover, gene expression of MC3T3-E1 cells cultured with different concentrations of sPGF is thoroughly assessed to elucidate the potential stimulating effect of sPGF on osteogenic differentiation. This study represents an innovative exploitation of EPD to develop textured surfaces by orientation of fibers in the macroscale, which shows great potential for directional functionalization of metallic implants.
Kamal, A; Ying, Y; Anderson, R G
1998-08-24
Previously we reported that annexin VI is required for the budding of clathrin-coated pits from human fibroblast plasma membranes in vitro. Here we show that annexin VI bound to the NH2-terminal 28-kD portion of membrane spectrin is as effective as cytosolic annexin VI in supporting coated pit budding. Annexin VI-dependent budding is accompanied by the loss of approximately 50% of the spectrin from the membrane and is blocked by the cysteine protease inhibitor N-acetyl-leucyl-leucyl-norleucinal (ALLN). Incubation of fibroblasts in the presence of ALLN initially blocks the uptake of low density lipoprotein (LDL), but the cells recover after 1 h and internalize LDL with normal kinetics. The LDL internalized under these conditions, however, fails to migrate to the center of the cell and is not degraded. ALLN-treated cells have twice as many coated pits and twofold more membrane clathrin, suggesting that new coated pits have assembled. Annexin VI is not required for the budding of these new coated pits and ALLN does not inhibit. Finally, microinjection of a truncated annexin VI that inhibits budding in vitro has the same effect on LDL internalization as ALLN. These findings suggest that fibroblasts are able to make at least two types of coated pits, one of which requires the annexin VI-dependent activation of a cysteine protease to disconnect the clathrin lattice from the spectrin membrane cytoskeleton during the final stages of budding.
NASA Technical Reports Server (NTRS)
Herley, P. J.; Levy, P. W.
1972-01-01
The X-ray and gamma-ray induced decomposition of ammonium perchlorate was studied by optical, transmission, and scanning electron microscopy. This material is a commonly used oxidizer in solid propellents which could be employed in deep-space probes, and where they will be subjected to a variety of radiations for as long as ten years. In some respects the radiation-induced damage closely resembles the effects produced by thermal decomposition, but in other respects the results differ markedly. Similar radiation and thermal effects include the following: (1) irregular or ill-defined circular etch pits are formed in both cases; (2) approximately the same size pits are produced; (3) the pit density is similar; (4) the c face is considerably more reactive than the m face; and (5) most importantly, many of the etch pits are aligned in crystallographic directions which are the same for thermal or radiolytic decomposition. Thus, dislocations play an important role in the radiolytic decomposition process.
NASA Astrophysics Data System (ADS)
Ye, Zhi-hao; Cai, Wen-xin; Li, Jin-feng; Chen, Xiang-rong; Zhang, Rui-feng; Birbilis, Nick; Chen, Yong-lai; Zhang, Xu-hu; Ma, Peng-cheng; Zheng, Zi-qiao
2018-06-01
The influences of annealing prior to solution treatment on the grain structure, subsequent aging precipitates, and intergranular corrosion (IGC) of Al-Cu-Li alloy (AA2050) sheet with T6 aging at 448 K (175 °C) were investigated. Annealing impedes the full recrystallization during solution treatment, increasing the population density of T1 (Al2CuLi) precipitates, but decreasing that of θ' (Al2Cu) precipitates, of the aged alloy. Meanwhile, annealing leads to the heterogeneous distribution of T1 precipitates, increasing the alloy hardness, and decreasing the open-circuit potential of the aged alloy. With prolonged aging time, the corrosion mode of the aged AA2050 samples with and without annealing evolved in a similar manner. The corrosion mode as a function of aging may be summarized as local IGC with pitting and general IGC with pitting (following initial aging and under the underaged condition), pitting corrosion (later in the under-aging stage), pitting with slight IGC (near the peak-aged condition), and pitting with local IGC (under the overaging condition). The annealing treatment hinders IGC propagation on the rolling surface while accelerating the IGC on transverse surfaces.
NASA Astrophysics Data System (ADS)
Ye, Zhi-hao; Cai, Wen-xin; Li, Jin-feng; Chen, Xiang-rong; Zhang, Rui-feng; Birbilis, Nick; Chen, Yong-lai; Zhang, Xu-hu; Ma, Peng-cheng; Zheng, Zi-qiao
2018-04-01
The influences of annealing prior to solution treatment on the grain structure, subsequent aging precipitates, and intergranular corrosion (IGC) of Al-Cu-Li alloy (AA2050) sheet with T6 aging at 448 K (175 °C) were investigated. Annealing impedes the full recrystallization during solution treatment, increasing the population density of T1 (Al2CuLi) precipitates, but decreasing that of θ' (Al2Cu) precipitates, of the aged alloy. Meanwhile, annealing leads to the heterogeneous distribution of T1 precipitates, increasing the alloy hardness, and decreasing the open-circuit potential of the aged alloy. With prolonged aging time, the corrosion mode of the aged AA2050 samples with and without annealing evolved in a similar manner. The corrosion mode as a function of aging may be summarized as local IGC with pitting and general IGC with pitting (following initial aging and under the underaged condition), pitting corrosion (later in the under-aging stage), pitting with slight IGC (near the peak-aged condition), and pitting with local IGC (under the overaging condition). The annealing treatment hinders IGC propagation on the rolling surface while accelerating the IGC on transverse surfaces.
NASA Technical Reports Server (NTRS)
Frisbee, Robert H.
2006-01-01
This paper presents the results of mission analyses that expose the advantages and disadvantages of high-power (MWe-class) Solar Electric Propulsion (SEP) for Lunar and Mars Cargo missions that would support human exploration of the Moon and Mars. In these analyses, we consider SEP systems using advanced Ion thrusters (the Xenon [Xe] propellant Herakles), Hall thrusters (the Bismuth [Bi] propellant Very High Isp Thruster with Anode Layer [VHITAL], magnetoplasmadynamic (MPD) thrusters (the Lithium [Li] propellant Advanced Lithium-Fed, Applied-field Lorentz Force Accelerator (ALFA2), and pulsed inductive thruster (PIT) (the Ammonia [NH3] propellant Nuclear-PIT [NuPIT]). The analyses include comparison of the advanced-technology propulsion systems (VHITAL, ALFA2, and NuPIT) relative to state-of-theart Ion (Herakles) propulsion systems and quantify the unique benefits of the various technology options such as high power-per-thruster (and/or high power-per-thruster packaging volume), high specific impulse (Isp), high-efficiency, and tankage mass (e.g., low tankage mass due to the high density of bismuth propellant). This work is based on similar analyses for Nuclear Electric Propulsion (NEP) systems.
Electrical Power Distribution and Control Modeling and Analysis
NASA Technical Reports Server (NTRS)
Fu, Johnny S.; Liffring, Mark; Mehdi, Ishaque S.
2001-01-01
This slide presentation reviews the use of Electrical Power Distribution and Control (EPD&C) Modeling and how modeling can support analysis. The presentation discusses using the EASY5 model to simulate and analyze the Space Shuttle Electric Auxiliary Power Unit. Diagrams of the model schematics are included, as well as graphs of the battery cell impedance, hydraulic load dynamics, and EPD&C response to hydraulic load variations.
Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers.
van Haaften, Caroline; Duke, Colin C; Weerheim, Arij M; Smit, Nico Pm; van Haard, Paul Mm; Darroudi, Firouz; Trimbos, Baptist Jmz
2011-03-14
Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue.In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid.Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL).Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects.Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. For the first time both crude plant extract from Calomeria amaranthoides and EPD have been shown to have potent anti-cancer effects against ovarian cancer.
Wasty, Najam; Khakwani, M. Z.; Kotev, Spas; Boiangiu, Catalin; Hasan, Omar; Anna, Manjusha; Tayal, Rajiv; Kaid, Khalil; Baker, Gail; Cohen, Marc
2016-01-01
This study aims to evaluate occurrence, size, composition, and clinical significance of embolized debris during superficial femoral artery atherectomy using all commercially available atherectomy devices. Distal athero/thromboembolic events (DATE) are a universal phenomenon in lower extremity atherectomy procedures (LEAPs) due to the sheer volume of atheroma and the thrombus burden in peripheral arterial disease. Some of these events can be clinically significant. We prospectively gathered clinical and histopathological data on all commercially available atherectomy devices by using embolic protection devices (EPD) in every case. After intervention, the contents of EPD were examined both microscopically and macroscopically. Data from 59 consecutive patients undergoing LEAP were analyzed. DATE occurred 100% of the time. The composition of particulate debris varied with the device used. Grossly visible agglomerated debris was captured by the filter in the majority of patients 54/59 (91.5%). Clinically significant debris, defined by the Preventing Lower Extremity Distal Embolization Using Embolic Filter Protection registry as particle diameter > 0.2 cm, was found in 33/59 (56%) patients. The size of captured debris particles ranged from 0.1 to 2.4 mm. While DATE occurred in all patients, clinically significant DATE occurred in 56% patients undergoing LEAP regardless of the atherectomy device. In spite of a large fraction of the clinically significant debris occurring on our routine dual antiplatelet regimen, no patient suffered an amputation. Although DATE was prevented by the use of EPD in all 59 cases, more data are needed to determine whether the use of EPD translates into a long-term clinical benefit. Use of EPD and optimal thromboprophylaxis should be considered in patients, especially in the setting of compromised distal runoff. PMID:27867291
Goyal, Kanika; Purbiya, Pragati; Lal, Sandeep N; Kaur, Jaspreet; Anthwal, Pooja; Puliyel, Jacob M
2017-06-01
Male bias in India has resulted in an altered sex ratio. It also results in maternal postpartum depression (PPD) and lower breastfeeding rates. We studied depression among fathers in this context. Edinburgh postnatal depression scale (EPDS) questionnaire was administered to 479 parents separately. Breastfeeding on day 7 was determined. Depression was significantly higher in fathers of girls. Mean EPDS score was 5.86 ± 4.98 versus 2.5 ± 2.64 (p < 0.001). Concordance between parents was significant (r = 0.95, p < 0.001). Boys were more likely to be exclusively breastfed (64.46% versus 35.54%, p < 0.001). In second-order births, if the first born was a girl and second baby was again a girl, 23% were exclusively breastfed compared with 86% if it was boy after a girl (p < 0.001). Among parents who had EPDS scores ≥11, no babies were exclusively breastfed. Among the 25 babies who received no breast milk, 21 were girls and 4 were boys (p < 0.042). The multiple logistic regression analysis indicated that birth of girls (OR 0.269, 95% CI 0.076-0.953), high EPDS score in mothers (OR = 0.080, 95% CI 0.026-0.249), and high EPDS score in fathers (OR = 0.096, 95% CI 0.031-0.299) were associated with lower breastfeeding rates. Paternal depression correlates closely with maternal PPD and low exclusive breastfeeding of girls. Breastfeeding has implications for survival of girls. Efforts are needed to support the parents of girl children with PPD and such support must extend to fathers to improve survival.
Nii, Kouhei; Tsutsumi, Masanori; Maeda, Hitoshi; Aikawa, Hiroshi; Inoue, Ritsuro; Eto, Ayumu; Sakamoto, Kimiya; Mitsutake, Takafumi; Hanada, Hayatsura; Kazekawa, Kiyoshi
2016-12-15
We investigated the angiographic findings and the clinical outcomes after carotid artery stenting (CAS) using two different, eccentric filter embolic protection devices (EPDs). Between July 2010 and August 2015, 175 CAS procedures were performed using a self-expandable closed-cell stent and a simple eccentric filter EPD (FilterWire EZ in 86 and Spider FX in 89 procedures). The angiographic findings (i.e., flow impairment and vasospasm) at the level of EPDs, neurologic events, and post-operative imaging results were compared between the FilterWire EZ and the Spider FX groups. The CAS was angiographically successful in all 175 procedures. However, the angiographs were obtained immediately after CAS-detected flow impairment in the distal internal carotid artery (ICA) in 11 (6.3%) and ICA spasms at the level of the EPD in 40 cases (22.9%). The incidence of these complications was higher with FilterWire EZ than Spider FX (ICA flow impairment of 10.5% vs. 2.2%, P = 0.03; vasospasm 30.2% vs. 15.7%, P = 0.03). There were nine neurologic events (5.1%); five patients were presented with transient ischemic attacks, three had minor strokes, and one had a major stroke. New MRI lesions were seen in 25 (29.1%) FilterWire-group and in 36 (40.4%) Spider-group patients. The neurologic events and new MRI lesions were not associated with the type of EPD used. Although the ICA flow impairment may result in neurologic events, there was no significant association between the FilterWire EZ and the Spider FX CAS with respect to the incidence of neurologic events by the prompt treatment such as catheter aspiration.
Daley, A J; Blamey, R V; Jolly, K; Roalfe, A K; Turner, K M; Coleman, S; McGuinness, M; Jones, I; Sharp, D J; MacArthur, C
2015-08-01
Postnatal depression affects about 10-15% of women in the year after giving birth. Many women and healthcare professionals would like an effective and accessible non-pharmacological treatment for postnatal depression. Women who fulfilled the International Classification of Diseases (ICD)-10 criteria for major depression in the first 6 months postnatally were randomized to receive usual care plus a facilitated exercise intervention or usual care only. The intervention involved two face-to-face consultations and two telephone support calls with a physical activity facilitator over 6 months to support participants to engage in regular exercise. The primary outcome was symptoms of depression using the Edinburgh Postnatal Depression Scale (EPDS) at 6 months post-randomization. Secondary outcomes included EPDS score as a binary variable (recovered and improved) at 6 and 12 months post-randomization. A total of 146 women were potentially eligible and 94 were randomized. Of these, 34% reported thoughts of self-harming at baseline. After adjusting for baseline EPDS, analyses revealed a -2.04 mean difference in EPDS score, favouring the exercise group [95% confidence interval (CI) -4.11 to 0.03, p = 0.05]. When also adjusting for pre-specified demographic variables the effect was larger and statistically significant (mean difference = -2.26, 95% CI -4.36 to -0.16, p = 0.03). Based on EPDS score a larger proportion of the intervention group was recovered (46.5% v. 23.8%, p = 0.03) compared with usual care at 6 months follow-up. This trial shows that an exercise intervention that involved encouragement to exercise and to seek out social support to exercise may be an effective treatment for women with postnatal depression, including those with thoughts of self-harming.
NASA Astrophysics Data System (ADS)
Apostol, Irina; Mahajan, Amit; Monty, Claude J. A.; Venkata Saravanan, K.
2015-12-01
A novel combination of solar physical vapor deposition (SPVD) and electrophoretic deposition (EPD) that was developed to grow MgTiO3 nanostructured thick films is presented. Obtaining nanostructured MgTiO3 thick films, which can replace bulk ceramic components, a major trend in electronic industry, is the main objective of this work. The advantage of SPVD is direct synthesis of nanopowders, while EPD is simple, fast and inexpensive technique for preparing thick films. SPVD technique was developed at CNRS-PROMES Laboratory, Odeillo-Font Romeu, France, while the EPD was performed at University of Aveiro - DeMAC/CICECO, Portugal. The nanopowders with an average crystallite size of about 30 nm prepared by SPVD were dispersed in 50 ml of acetone in basic media with addition of triethanolamine. The obtained well-dispersed and stable suspensions were used for carrying out EPD on 25 μm thick platinum foils. After deposition, films with thickness of about 22-25 μm were sintered in air for 15 min at 800, 900 and 1000 °C. The structural and microstructural characterization of the sintered thick films was carried out using XRD and SEM, respectively. The thickness of the sintered samples were about 18-20 μm, which was determined by cross-sectional SEM. Films sintered at 900 °C exhibit a dielectric constant, ɛr ∼18.3 and dielectric loss, tan δ ∼0.0012 at 1 MHz. The effects of processing techniques (SPVD and EPD) on the structure, microstructure and dielectric properties are reported in detail. The obtained results indicate that the thick films obtained in the present study can be promising for low loss materials for microwave and millimeter wave applications.
Surface free energy of TiC layers deposited by electrophoretic deposition (EPD)
NASA Astrophysics Data System (ADS)
Gorji, Mohammad Reza; Sanjabi, Sohrab
2018-01-01
In this study porous structure coatings of bare TiC (i.e. 20 nm, 0.7 µm and 5/45 µm) and core-shell structures of TiC/NiP synthesized through electroless plating were deposited by EPD. Room temperature surface free energy (i.e. γs) of TiC and TiC/NiP coatings were determined via measuring contact angles of distilled water and diiodemethane liquids. The effect of Ni-P shell on spreading behavior of pure copper on porous EPD structures was also investigated by high temperature wetting experiments. According to the results existence of a Ni-P layer around the TiC particles has led to roughness (i.e. at least 0.1 µm), and porosity mean length (i.e. at least 1 µm) increase. This might be related to various sizes of TiC agglomerates formed during electroless plating. It has been observed that room temperature γs changed from 44.49 to 54.12 mJ.m-2 as a consequence of particle size enlargement for TiC. The highest and lowest (67.25 and 44.49 mJ.m-2) γs were measured for TiC nanoparticles which showed 1.5 times increase in surface free energy after being plated with Ni-P. It was also observed that plating Ni-P altered non-spreading (θs > 100 o) behavior of TiC to full-spreading ((θs 0o)) which can be useful for preparation of hard coatings by infiltration sintering phenomenon. Zeta potential of EPD suspensions, morphology, phase structure and topography of as-EPD layers were investigated through Zetasizer, field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and atomic force microscopy (AFM) instruments respectively.
Simpson, William; Glazer, Melanie; Michalski, Natalie; Steiner, Meir; Frey, Benicio N
2014-08-01
About 24.1% of pregnant women suffer from at least 1 anxiety disorder, 8.5% of whom suffer specifically from generalized anxiety disorder (GAD). GAD is often associated with major depressive disorder (MDD). During the perinatal period, the presence of physical and somatic symptoms often makes differentiation between depression and anxiety more challenging. To date, no screening tools have been developed to detect GAD in the perinatal population. We investigated the psychometric properties of the GAD 7-item Scale (GAD-7) as a screening tool for GAD in pregnant and postpartum women. Two hundred and forty perinatal women (n = 155 pregnant and n = 85 postpartum) referred for psychiatric consultation were enrolled. On the day of initial assessment, all women completed the GAD-7 and the Edinburgh Postnatal Depression Scale (EPDS). Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-based diagnoses were made by experienced psychiatrists. Scores from the GAD-7 and EPDS were compared with the clinical diagnoses to evaluate the psychometric properties of the GAD-7 and EPDS when used as a screening tool for GAD. The GAD-7 yielded a sensitivity of 61.3% and specificity of 72.7% at an optimal cut-off score of 13. Compared with the EPDS and the EPDS-3A subscale, the GAD-7 displayed greater accuracy and specificity over a greater range of cut-off scores and more accurately identified GAD in patients with comorbid MDD. Our findings suggest that the GAD-7 represents a clinically useful scale for the detection of GAD in perinatal women.
Screening mixed depression and bipolarity in the postpartum period at a primary health care center.
Çelik, Sercan Bulut; Bucaktepe, Gamze Erten; Uludağ, Ayşegül; Bulut, İbrahim Umud; Erdem, Özgür; Altınbaş, Kürşat
2016-11-01
Mixed depression is a clinical condition accompanied by the symptoms of (hypo)mania and is considered to be a predictor for bipolar disorder. Compared to pure major depression, mixed depression is worse in progress. There are limited data on the prevalence of mixed depression since it is a relatively new entity. Therefore, the present study aimed to investigate the prevalence of mixed depression during the postpartum period which is risky for mood disorders. The study included 63 postpartum women. The participants were administered Beck Depression Scale, Edinburgh Postnatal Depression Scale (EPDS), Mood Disorders Questionnaire (MDQ), and Modified Hypomania Symptom Checklist-32 (mHCL-32). The MDQ scores of the women with expected depression according to the EPDS cut-off scores, were significantly higher than the women with lower EPDS scores (t=-4.968; p<0.001). The modified hypomania scores were significantly higher in the women with higher depression scores compared to the women under EPDS cut-off scores (t=-4.713; p<0.001). According to the EPDS and BDS results, 27 (42.9%) and 14 (22.2%) women needed additional clinical examination for depression, respectively. In addition, 3 (4.8%) women require additional clinical examination for bipolar disorder. The scores for the first item of MDQ were above the cut-off value in 11 (17.5%) women. According to the mHCL-32 results, 50 (79.4%) women had at least 1 symptom, 45 (71.4%) women had at least 3 symptoms, and 43 (68.3%) women had at least 5 symptoms of mixed depression. Postpartum mixed depression should be promptly diagnosed by using appropriate diagnostic tools, particularly by primary health care physicians. Patients with mixed depression should be closely monitored to avoid manic switch. Copyright © 2016 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leonhardt, Darin; Han, Sang M.
2011-09-12
We report a technique that significantly reduces threading dislocations in Ge on Si heteroepitaxy. Germanium is first grown on Si and etched to produce pits in the surface where threading dislocations terminate. Further processing leaves a layer of SiO{sub 2} only within etch pits. Subsequent selective epitaxial Ge growth results in coalescence above the SiO{sub 2}. The SiO{sub 2} blocks the threading dislocations from propagating into the upper Ge epilayer. With annealed Ge films grown on Si, the said method reduces the defect density from 2.6 x 10{sup 8} to 1.7 x 10{sup 6} cm{sup -2}, potentially making the layermore » suitable for electronic and photovoltaic devices.« less
Construction of the STAR Event Plane Detector
NASA Astrophysics Data System (ADS)
Adams, Joseph
2017-09-01
The Event Plane Detector (EPD) is an upgrade to the STAR experiment at RHIC, providing high granularity and acceptance in the forward (2.2 < |eta| < 5.1) region. This will improve the resolution of the event plane determination and allow selection on the collision centrality at rapidities well-separated from the midrapidity region measured by the STAR Time Projection Chamber (TPC). The EPD consists of two scintillator discs, one at positive and one at negative rapidity, 3.75 m from the center of the TPC. Each disc is segmented into 372 optically isolated tiles, read out by wavelength shifting fibers coupled to silicon photomultipliers. One quarter of a single disc was installed in STAR for the 2017 run for commissioning. In this talk I will discuss the construction of the EPD, the installation of the quarter wheel, and plans for full installation in 2018.
Local electronic and optical behavior of ELO a-plane GaN
NASA Astrophysics Data System (ADS)
Baski, A. A.; Moore, J. C.; Ozgur, U.; Kasliwal, V.; Ni, X.; Morkoc, H.
2007-03-01
Conductive atomic force microscopy (CAFM) and near-field optical microscopy (NSOM) were used to study a-plane GaN films grown via epitaxial lateral overgrowth (ELO). The ELO films were prepared by metal organic chemical vapor deposition on a patterned SiO2 layer with 4-μm wide windows, which was deposited on a GaN template grown on r-plane sapphire. The window regions of the coalesced ELO films appear as depressions with a high density of surface pits. At reverse bias below 12 V, very low uniform conduction (2 pA) is seen in the window regions. Above 20 V, a lower-quality sample shows localized sites inside the window regions with significant leakage, indicating a correlation between the presence of surface pits and leakage sites. Room temperature NSOM studies also suggest a greater density of surface terminated dislocations in the window regions, while wing regions explicitly show enhanced optical quality of the overgrown GaN. The combination of CAFM and NSOM data therefore indicates a correlation between the presence of surface pits, localized reverse-bias current leakage, and low PL intensity in the window regions.
NASA Astrophysics Data System (ADS)
Ajuria, Jon; Redondo, Edurne; Arnaiz, Maria; Mysyk, Roman; Rojo, Teófilo; Goikolea, Eider
2017-08-01
In this work, we are presenting both lithium and sodium ion capacitors (LIC and NIC) entirely based on electrodes designed from recycled olive pit bio-waste derived carbon materials. On the one hand, olive pits were pyrolized to obtain a low specific surface area semigraphitic hard carbon to be used as the ion intercalation (battery-type) negative electrode. On the other hand, the same hard carbon was chemically activated with KOH to obtain a high specific surface area activated carbon that was further used as the ion-adsorption (capacitor-type) positive electrode. Both electrodes were custom-made to be assembled in a hybrid cell to either build a LIC or NIC in the corresponding Li- and Na-based electrolytes. For comparison purposes, a symmetric EDLC supercapacitor cell using the same activated carbon in 1.5 M Et4NBF4/acetonitrile electrolyte was also built. Both LIC and NIC systems demonstrate remarkable energy and power density enhancement over its EDLC counterpart while showing good cycle life. This breakthrough offers the possibility to easily fabricate versatile hybrid ion capacitors, covering a wide variety of applications where different requirements are demanded.
Wang, Tong-Mei; Lee, Ming-Shu; Wang, Juo-Song; Lin, Li-Deh
2015-01-01
This study investigated the effect of implant design and bone quality on insertion torque (IT), implant stability quotient (ISQ), and insertion energy (IE) by monitoring the continuous change in IT and ISQ while implants were inserted in artificial bone blocks that simulate bone of poor or poor-to-medium quality. Polyurethane foam blocks (Sawbones) of 0.16 g/cm³ and 0.32 g/cm³ were respectively used to simulate low density and low- to medium-density cancellous bone. In addition, some test blocks were laminated with a 1-mm 0.80 g/cm³ polyurethane layer to simulate cancellous bone with a thin cortical layer. Four different implants (Nobel Biocare Mk III-3.75, Mk III-4.0, Mk IV-4.0, and NobelActive-4.3) were placed into the different test blocks in accordance with the manufacturer's instructions. The IT and ISQ were recorded at every 0.5-mm of inserted length during implant insertion, and IE was calculated from the torque curve. The peak IT (PIT), final IT (FIT), IE, and final ISQ values were statistically analyzed. All implants showed increasing ISQ values when the implant was inserted more deeply. In contrast to the ISQ, implants with different designs showed dissimilar IT curve patterns during the insertion. All implants showed a significant increase in the PIT, FIT, IE, and ISQ when the test-block density increased or when the 1-mm laminated layer was present. Tapered implants showed FIT or PIT values of more than 40 Ncm for all of the laminated test blocks and for the nonlaminated test blocks of low to medium density. Parallel-wall implants did not exhibit PIT or FIT values of more than 40 Ncm for all of the test blocks. NobelActive-4.3 showed a significantly higher FIT, but a significantly lower IE, than Mk IV-4.0. While the existence of cortical bone or implant designs significantly affects the dynamic IT profiles during implant insertion, it does not affect the ISQ to a similar extent. Certain implant designs are more suitable than others if high IT is required in bone of poor quality. The manner in which IT, IE, and ISQ represent the implant primary stability requires further study.
Energy Production Demonstrator for Megawatt Proton Beams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pronskikh, Vitaly S.; Mokhov, Nikolai V.; Novitski, Igor
2014-07-16
A preliminary study of the Energy Production Demonstrator (EPD) concept - a solid heavy metal target irradiated by GeV-range intense proton beams and producing more energy than consuming - is carried out. Neutron production, fission, energy deposition, energy gain, testing volume and helium production are simulated with the MARS15 code for tungsten, thorium, and natural uranium targets in the proton energy range 0.5 to 120 GeV. This study shows that the proton energy range of 2 to 4 GeV is optimal for both a natU EPD and the tungsten-based testing station that would be the most suitable for proton acceleratormore » facilities. Conservative estimates, not including breeding and fission of plutonium, based on the simulations suggest that the proton beam current of 1 mA will be sufficient to produce 1 GW of thermal output power with the natU EPD while supplying < 8% of that power to operate the accelerator. The thermal analysis shows that the concept considered has a problem due to a possible core meltdown; however, a number of approaches (a beam rastering, in first place) are suggested to mitigate the issue. The efficiency of the considered EPD as a Materials Test Station (MTS) is also evaluated in this study.« less
Fiorilli, Sonia; Baino, Francesco; Cauda, Valentina; Crepaldi, Marco; Vitale-Brovarone, Chiara; Demarchi, Danilo; Onida, Barbara
2015-01-01
In this work, the coating of 3-D foam-like glass-ceramic scaffolds with a bioactive mesoporous glass (MBG) was investigated. The starting scaffolds, based on a non-commercial silicate glass, were fabricated by the polymer sponge replica technique followed by sintering; then, electrophoretic deposition (EPD) was applied to deposit a MBG layer on the scaffold struts. EPD was also compared with other techniques (dipping and direct in situ gelation) and it was shown to lead to the most promising results. The scaffold pore structure was maintained after the MBG coating by EPD, as assessed by SEM and micro-CT. In vitro bioactivity of the scaffolds was assessed by immersion in simulated body fluid and subsequent evaluation of hydroxyapatite (HA) formation. The deposition of a MBG coating can be a smart strategy to impart bioactive properties to the scaffold, allowing the formation of nano-structured HA agglomerates within 48 h from immersion, which does not occur on uncoated scaffold surfaces. The mechanical properties of the scaffold do not vary after the EPD (compressive strength ~19 MPa, fracture energy ~1.2 × 10(6) J m(-3)) and suggest the suitability of the prepared highly bioactive constructs as bone tissue engineering implants for load-bearing applications.
Measurements of occupational exposure for a technologist performing 18F FDG PET scans.
Biran, Talma; Weininger, Jolie; Malchi, Shalom; Marciano, Rami; Chisin, Roland
2004-11-01
Radiation doses to one PET technologist performing 100 18F FDG (18F fluorodeoxyglucose) imaging procedures were measured in a clinical setting using two types of thermoluminescent dosimeter (TLD) badges, one finger-ring TLD and one electronic pocket dosimeter (EPD). 18F FDG was handled either with unshielded or with viewing window tungsten shielded syringes. The resulting doses using unshielded syringes were 13.8 +/- 0.8 microSv/370 MBq and 14.3 +/- 0.4 microSv/370 MBq, measured with TLD 100 and with TLD 700H/600H, respectively. For the same series of measurements, the doses obtained using shielded syringes were 10.7 +/- 0.4 microSv/370 MBq and 7.2 +/- 2.1 microSv/370 MBq with TLD700H/600H and with EPD, respectively. The dose to the right hand from shielded syringes was 69.3 +/- 5.5 microSv/370 MBq. All these values are within the ICRP recommended dose limits. Extrapolated to 725 examinations per year, the resulting effective dose measured with TLD would be 10 mSv with unshielded and 7.5 mSv with shielded syringes, respectively (25% dose reduction). The doses measured by TLD were consistently higher than those measured by EPD, suggesting that EPD measurements might underestimate occupational doses.
Chiu, Yueh-Hsiu Mathilda; Sheffield, Perry E; Hsu, Hsiao-Hsien Leon; Goldstein, Jonathan; Curtin, Paul C; Wright, Rosalind J
2017-12-01
The ten-item Edinburgh Postnatal Depression Scale (EPDS) is one of the most widely used self-report measures of postpartum depression. Although originally described as a one-dimensional measure, the recognition that depressive symptoms may be differentially experienced across cultural and racial/ethnic groups has led to studies examining structural equivalence of the EPDS in different populations. Variation of the factor structure remains understudied across racial/ethnic groups of US women. We examined the factor structure of the EPDS assessed 6 months postpartum in 515 women (29% black, 53% Hispanic, 18% white) enrolled in an urban Boston longitudinal birth cohort. Exploratory factor analysis (EFA) identified that a three-factor model, including depression, anxiety, and anhedonia subscales, was the most optimal fit in our sample as a whole and across race/ethnicity. Confirmatory factor analysis (CFA) was used to examine the fit of both the two- and three-factor models reported in prior research. CFA confirmed the best fit for a three-factor model, with minimal differences across race/ethnicity. "Things get on top of me" loaded on the anxiety factor among Hispanics, but loaded on the depression factor in whites and African Americans. These findings suggest that EPDS factor structure may need to be adjusted for diverse samples and warrants further study.
Henshaw, Erin J; Fried, Rachel; Teeters, Jenni Beth; Siskind, Emily E
2014-09-01
Several predictors of postpartum mood have been identified in the literature, but the role of maternal expectations in postpartum mental health remains unclear. The aim of this study was to identify whether maternal expectations during the postpartum hospital stay predict adjustment and depressive symptoms at 6 weeks postpartum. The sample included 233 first-time mothers recruited from the postpartum unit of a Midwestern hospital. Participants completed measures of maternal expectations and depressive symptoms (EPDS) at Time 1 (2 d postpartum) and completed EPDS and an Emotional Adjustment Scale (BaM-13) at Time 2 (6 weeks postpartum). A conditional relationship between the expectation that an infant's behavior will reflect maternal skill and Time 2 outcomes (BaM-13 and EPDS) was found, such that endorsing this belief predicted increased depression and poorer adjustment in those with higher (but not lower) Time 1 EPDS scores. Time 2 BaM-13 scores were also negatively predicted by expectations of self-sacrifice and positively predicted by expectations that parenthood would be naturally fulfilling. The expectations that new mothers hold about parenting soon after delivery are predictive of emotional adjustment in the early postpartum period, suggesting a role for discussion of expectations in future preventive strategies.
Laso, Jara; Margallo, María; Fullana, Pére; Bala, Alba; Gazulla, Cristina; Irabien, Ángel; Aldaco, Rubén
2017-01-01
To be able to fulfil high market expectations for a number of practical applications, Environmental Product Declarations (EPDs) have to meet and comply with specific and strict methodological prerequisites. These expectations include the possibility to add up Life Cycle Assessment (LCA)-based information in the supply chain and to compare different EPDs. To achieve this goal, common and harmonized calculation rules have to be established, the so-called Product Category Rules (PCRs), which set the overall LCA calculation rules to create EPDs. This document provides PCRs for the assessment of the environmental performance of canned anchovies in Cantabria Region based on an Environmental Sustainability Assessment (ESA) method. This method uses two main variables: the natural resources sustainability (NRS) and the environmental burdens sustainability (EBS). To reduce the complexity of ESA and facilitate the decision-making process, all variables are normalized and weighted to obtain two global dimensionless indexes: resource consumption (X 1 ) and environmental burdens (X 2 ). •This paper sets the PCRs adapted to the Cantabrian canned anchovies.•ESA method facilitates the product comparison and the decision-making process.•This paper stablishes all the steps that an EPD should include within the PCRs of Cantabrian canned anchovies.
Controlled trial of hyposensitisation in children with food-induced hyperkinetic syndrome.
Egger, J; Stolla, A; McEwen, L M
1992-05-09
Food intolerance seems to be an important cause of the hyperkinetic syndrome, but restricted diets are expensive, socially disruptive, and often nutritionally inadequate. Enzyme-potentiated desensitisation (EPD) may overcome some of these difficulties. EPD was tested in a double-blind placebo-controlled trial among 40 children with food-induced hyperkinetic behaviour disorder. A total of 185 children with established hyperkinetic syndrome underwent oligoantigenic dietary treatment for four weeks. 116 whose behaviour responded had provoking foods identified by sequential reintroduction. Foods that reproducibly provoked overactivity were avoided. 40 patients who were then invited to take part in the hyposensitisation trial were randomly assigned to treated and control groups. Treated patients received three doses of EPD (beta-glucuronidase and small quantities of food antigens) intradermally at two-monthly intervals. Controls received buffer only. Thereafter, patients were allowed to eat known provoking foods. Of 20 patients who received active treatment, 16 became tolerant towards provoking foods compared with 4 of 20 who received placebo (p less than 0.001). Our results show that EPD permits children with food-induced hyperkinetic syndrome to eat foods that had previously been identified as responsible for their symptoms. These results also support the notion that food allergy is a possible mechanism of the hyperkinetic syndrome.
NASA Astrophysics Data System (ADS)
Amirnejad, M.; Afshar, A.; Salehi, S.
2018-05-01
Composite coatings of Hydroxyapatite (HA) with ceramics, polymers and metals are used to modify the surface structure of implants. In this research, HA/TiO2 composite coating was fabricated by electrophoretic deposition (EPD) on 316 stainless steel substrate. HA/TiO2 composite coatings with 5, 10 and 20 wt.% of TiO2, deposited at 40 V and 90 s as an optimum condition. The samples coated at this condition led to an adherent, continuous and crack-free coating. The influence of TiO2 content was studied by performing different characterization methods such as scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), corrosion resistance in simulated body fluid (SBF), coating's dissolution rate in physiological solution and bond strength to the substrate. The results showed that the higher amount of TiO2 in the composite coating led to increase in bond strength of coating to stainless steel substrate from 3 MPa for HA coating to 5.5 MPa for HA-20 wt.% TiO2 composite coating. In addition, it caused to reduction of corrosion current density of samples in the SBF solution from 18.92 μA/cm2 for HA coating to 6.35 μA/cm2 for HA-20 wt.% TiO2 composite coating.
NASA Astrophysics Data System (ADS)
Amirnejad, M.; Afshar, A.; Salehi, S.
2018-04-01
Composite coatings of Hydroxyapatite (HA) with ceramics, polymers and metals are used to modify the surface structure of implants. In this research, HA/TiO2 composite coating was fabricated by electrophoretic deposition (EPD) on 316 stainless steel substrate. HA/TiO2 composite coatings with 5, 10 and 20 wt.% of TiO2, deposited at 40 V and 90 s as an optimum condition. The samples coated at this condition led to an adherent, continuous and crack-free coating. The influence of TiO2 content was studied by performing different characterization methods such as scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), corrosion resistance in simulated body fluid (SBF), coating's dissolution rate in physiological solution and bond strength to the substrate. The results showed that the higher amount of TiO2 in the composite coating led to increase in bond strength of coating to stainless steel substrate from 3 MPa for HA coating to 5.5 MPa for HA-20 wt.% TiO2 composite coating. In addition, it caused to reduction of corrosion current density of samples in the SBF solution from 18.92 μA/cm2 for HA coating to 6.35 μA/cm2 for HA-20 wt.% TiO2 composite coating.
Growth of ZnO films in sol-gel electrophoretic deposition by different solvents
NASA Astrophysics Data System (ADS)
Hallajzadeh, Amir Mohammad; Abdizadeh, Hossein; Taheri, Mahtab; Golobostanfard, Mohammad Reza
2018-01-01
This article introduces a process to fabricate zinc oxide (ZnO) films through combining sol preparation and electrophoretic deposition (EPD). The experimental results have proved that the EPD process is a powerful route to fabricate ZnO films with desire thickness from stable colloidal suspension under a direct current (DC) electric field. In this method, ZnO sol is prepared by dissolving zinc acetate dehydrate (ZAD) as the main precursor and diethanolamine (DEA) as the additive in various solvents such as methanol (MeOH), ethanol (EtOH), and 2-proponal (2-PrOH). The deposition was performed under a constant voltage of 30 V for 2 min. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and diffuse reflectance spectroscopy (DRS) were used to characterize ZnO films. XRD pattern of the ZnO film prepared by MeOH shows the highest degree of preferential orientation and this is mainly attributed to the higher dielectric constant of the MeOH which results in higher current density in electrophoretic deposit ion. The SEM cross section images also show that the thickness of the ZnO film enhances by decreasing the solvent chain length. According to SEM results, as the viscosity of the medium increased, more compact layers are formed, which can be attributed to the lower deposition rates in heavier alcohols.
Cao, C.; Argonne National Lab.; Ford, D.; ...
2013-06-26
Raman microscopy/spectroscopy measurements are presented on high purity niobium (Nb) samples, including pieces from hot spot regions of a tested superconducting rf cavity that exhibit a high density of etch pits. Measured spectra are compared with density functional theory calculations of Raman-active, vibrational modes of possible surface Nb-O and Nb-H complexes. The Raman spectra inside particularly rough pits in all Nb samples show clear differences from surrounding areas, exhibiting enhanced intensity and sharp peaks. While some of the sharp peaks are consistent with calculated NbH and NbH 2 modes, there is better overall agreement with C-H modes in chain-type hydrocarbons.more » Other spectra reveal two broader peaks attributed to amorphous carbon. Niobium foils annealed to >2000°C in high vacuum develop identical Raman peaks when subjected to cold working. Regions with enhanced C and O have also been found by SEM/EDX spectroscopy in the hot spot samples and cold-worked foils, corroborating the Raman results. Such regions with high concentrations of impurities are expected to suppress the local superconductivity and this may explain the correlation between hot spots in superconducting rf (SRF) cavities and the observation of a high density of surface pits. Finally, the origin of localized high carbon and hydrocarbon regions is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cao, C.; Argonne National Lab.; Ford, D.
Raman microscopy/spectroscopy measurements are presented on high purity niobium (Nb) samples, including pieces from hot spot regions of a tested superconducting rf cavity that exhibit a high density of etch pits. Measured spectra are compared with density functional theory calculations of Raman-active, vibrational modes of possible surface Nb-O and Nb-H complexes. The Raman spectra inside particularly rough pits in all Nb samples show clear differences from surrounding areas, exhibiting enhanced intensity and sharp peaks. While some of the sharp peaks are consistent with calculated NbH and NbH 2 modes, there is better overall agreement with C-H modes in chain-type hydrocarbons.more » Other spectra reveal two broader peaks attributed to amorphous carbon. Niobium foils annealed to >2000°C in high vacuum develop identical Raman peaks when subjected to cold working. Regions with enhanced C and O have also been found by SEM/EDX spectroscopy in the hot spot samples and cold-worked foils, corroborating the Raman results. Such regions with high concentrations of impurities are expected to suppress the local superconductivity and this may explain the correlation between hot spots in superconducting rf (SRF) cavities and the observation of a high density of surface pits. Finally, the origin of localized high carbon and hydrocarbon regions is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.« less
NASA Astrophysics Data System (ADS)
Wei, Xing; Sugri Nbelayim, Pascal; Kawamura, Go; Muto, Hiroyuki; Matsuda, Atsunori
2017-03-01
A layer of TiO2 nanotube (TNT) arrays with a thickness of 13 μm is synthesized by a two-step anodic oxidation from Ti metal foil. Surface charged Ag nanoparticles (NPs) are prepared by chemical reduction. After a pretreatment of the TNT arrays by acetone vapor, Ag NP filled TNT arrays can be achieved by electrophoretic deposition (EPD). Effects of the applied voltage during EPD such as DC-AC difference, frequency and waveform are investigated by quantitative analysis using atomic absorption spectroscopy. The results show that the best EPD condition is using DC 2 V + AC 4 V and a square wave of 1 Hz as the applied voltage. Back illuminated dye-sensitized solar cells are fabricated from TNT arrays with and without Ag NPs. The efficiency increased from 3.70% to 5.01% by the deposition of Ag NPs.
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.
Inverse Energy Dispersion of Energetic Ions Observed in the Magnetosheath
NASA Technical Reports Server (NTRS)
Lee, S. H.; Sibeck, D. G.; Hwang, K.-J.; Wang, Y.; Silveira, M. V. D.; Fok, M.-C.; Mauk, B. H.; Cohen, I. J.; Ruohoniemi, J. M.; Kitamura, N.;
2016-01-01
We present a case study of energetic ions observed by the Energetic Particle Detector (EPD) on the Magnetospheric Multiscale spacecraft in the magnetosheath just outside the subsolar magnetopause that occurred at 1000 UT on 8 December 2015. As the magnetopause receded inward, the EPD observed a burst of energetic (approximately 50-1000 keV) proton, helium, and oxygen ions that exhibited an inverse dispersion, with the lowest energy ions appearing first. The prolonged interval of fast antisunward flow observed in the magnetosheath and transient increases in the H components of global ground magnetograms demonstrate that the burst appeared at a time when the magnetosphere was rapidly compressed. We attribute the inverse energy dispersion to the leakage along reconnected magnetic field lines of betatron-accelerated energetic ions in the magnetosheath, and a burst of reconnection has an extent of about 1.5 R(sub E) using combined Super Dual Auroral Radar Network radar and EPD observations.
Radice, S; Kern, P; Dietsch, H; Mischler, S; Michler, J
2008-02-15
Functionalization of colloidal particles based on the use of polyelectrolytes and heterocoagulation was combined with electrophoretic deposition (EPD), with the aim of depositing titania-polystyrene (TiO(2)-PS) composite particles on Ti6Al4V substrates. The composite particles were obtained by heterocoagulation of TiO(2) nanoparticles on the surface of monosized polystyrene beads of 4.6 microm in diameter. Two alternative methods were developed for the preparation of the TiO(2)-PS suspensions in organic fluids for cathodic electrodeposition. The first method was carried out in alkaline aqueous medium with the use of polyelectrolytes and intermediate control measurements of zeta potential, conductivity, and pH; the second one was carried out directly in the organic solvent used for EPD, typically isopropanol. Examples of deposits obtained by EPD in both suspensions and a comparative analysis between the two methods are presented.
Yadav, Manisha C.; Bottini, Massimo; Cory, Esther; Bhattacharya, Kunal; Kuss, Pia; Narisawa, Sonoko; Sah, Robert L.; Beck, Laurent; Fadeel, Bengt; Farquharson, Colin; Millán, José Luis
2016-01-01
We have previously shown that ablation of either the Phospho1 or Alpl gene, encoding PHOSPHO1 and tissue-nonspecific alkaline phosphatase (TNAP) respectively, lead to hyperosteoidosis but that their chondrocyte- and osteoblast-derived matrix vesicles (MVs) are able to initiate mineralization. In contrast, the double ablation of Phospho1 and Alpl completely abolish initiation and progression of skeletal mineralization. We argued that MVs initiate mineralization by a dual mechanism: PHOSPHO1-mediated intravesicular generation of Pi and phosphate transporter-mediated influx of Pi. To test this hypothesis, we generated mice with col2a1-driven cre-mediated ablation of Slc20a1, hereafter referred to as Pit1, alone or in combination with a Phospho1 gene deletion. Pit1col2/col2 mice did not show any major phenotypic abnormalities, while severe skeletal deformities were observed in the [Phospho1−/−; Pit1col2/col2] double knockout mice that were more pronounced than those observed in the Phospho1−/− mice. Histological analysis of [Phospho1−/−; Pit1col2/col2] bones showed growth plate abnormalities with a shorter hypertrophic chondrocyte zone and extensive hyperosteoidosis. The [Phospho1−/−; Pit1col2/col2] skeleton displayed significantly decreases in BV/TV%, trabecular number and bone mineral density, as well as decreased stiffness, decreased strength, and increased post-yield deflection compared to Phospho1−/− mice. Using atomic force microscopy we found that ~80% of [Phospho1−/−; Pit1col2/col2] MVs were devoid of mineral in comparison to ~50 % for the Phospho1−/− MVs and ~25% for the WT and Pit1col2/col2 MVs. We also found a significant decrease in the number of MVs produced by both Phospho1−/− and [Phospho1−/−; Pit1col2/col2] chondrocytes. These data support the involvement of PiT-1 in the initiation of skeletal mineralization and provide compelling evidence that PHOSPHO1 function is involved in MV biogenesis. PMID:26773408
Pyramidal pits created by single highly charged ions in BaF{sub 2} single crystals
DOE Office of Scientific and Technical Information (OSTI.GOV)
El-Said, A. S.; Physics Department, Faculty of Science, Mansoura University, 35516 Mansoura; Heller, R.
2010-07-15
In various insulators, the impact of individual slow highly charged ions (eV-keV) creates surface nanostructures, whose size depends on the deposited potential energy. Here we report on the damage created on a cleaved BaF{sub 2} (111) surface by irradiation with 4.5xq keV highly charged xenon ions from a room-temperature electron-beam ion trap. Up to charge states q=36, no surface topographic changes on the BaF{sub 2} surface are observed by scanning force microscopy. The hidden stored damage, however, can be made visible using the technique of selective chemical etching. Each individual ion impact develops into a pyramidal etch pits, as canmore » be concluded from a comparison of the areal density of observed etch pits with the applied ion fluence (typically 10{sup 8} ions/cm{sup 2}). The dimensional analysis of the measured pits reveals the significance of the deposited potential energy in the creation of lattice distortions/defects in BaF{sub 2}.« less
Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers
2011-01-01
Background Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. Methods The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue. In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Results Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid. Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL). Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects. Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. Conclusions For the first time both crude plant extract from Calomeria amaranthoides and EPD have been shown to have potent anti-cancer effects against ovarian cancer. PMID:21401934
Sampling for Soil Carbon Stock Assessment in Rocky Agricultural Soils
NASA Technical Reports Server (NTRS)
Beem-Miller, Jeffrey P.; Kong, Angela Y. Y.; Ogle, Stephen; Wolfe, David
2016-01-01
Coring methods commonly employed in soil organic C (SOC) stock assessment may not accurately capture soil rock fragment (RF) content or soil bulk density (rho (sub b)) in rocky agricultural soils, potentially biasing SOC stock estimates. Quantitative pits are considered less biased than coring methods but are invasive and often cost-prohibitive. We compared fixed-depth and mass-based estimates of SOC stocks (0.3-meters depth) for hammer, hydraulic push, and rotary coring methods relative to quantitative pits at four agricultural sites ranging in RF content from less than 0.01 to 0.24 cubic meters per cubic meter. Sampling costs were also compared. Coring methods significantly underestimated RF content at all rocky sites, but significant differences (p is less than 0.05) in SOC stocks between pits and corers were only found with the hammer method using the fixed-depth approach at the less than 0.01 cubic meters per cubic meter RF site (pit, 5.80 kilograms C per square meter; hammer, 4.74 kilograms C per square meter) and at the 0.14 cubic meters per cubic meter RF site (pit, 8.81 kilograms C per square meter; hammer, 6.71 kilograms C per square meter). The hammer corer also underestimated rho (sub b) at all sites as did the hydraulic push corer at the 0.21 cubic meters per cubic meter RF site. No significant differences in mass-based SOC stock estimates were observed between pits and corers. Our results indicate that (i) calculating SOC stocks on a mass basis can overcome biases in RF and rho (sub b) estimates introduced by sampling equipment and (ii) a quantitative pit is the optimal sampling method for establishing reference soil masses, followed by rotary and then hydraulic push corers.
Zhong, Qiu-Yue; Gelaye, Bizu; Rondon, Marta B; Sánchez, Sixto E; Simon, Gregory E; Henderson, David C; Barrios, Yasmin V; Sánchez, Pedro Mascaro; Williams, Michelle A
2015-12-01
We sought to examine the concordance of two suicidal ideation items from the Patient Health Questionnaire-9 (PHQ-9) and the Edinburgh Postnatal Depression Scale (EPDS), to evaluate the prevalence of suicidal ideation among pregnant women, and to assess the co-occurrence of suicidal ideation with antepartum depressive symptoms. A cross-sectional study was conducted among 1,517 pregnant women attending prenatal care clinics in Lima, Peru. Item 9 of the PHQ-9 assesses suicidal ideation over the last 14 days while item 10 of the EPDS assesses suicidal ideation in the past 7 days. The two suicidal ideation items have a high concordance rate (84.2 %) but a moderate agreement (the Cohen's kappa = 0.42). Based on the PHQ-9 and the EPDS, 15.8 and 8.8 % of participants screened positive for suicidal ideation, respectively. Assessed by the PHQ-9, 51 % of participants with suicidal ideation had probable depression. In prenatal care clinics, screening for suicidal ideation is needed for women with and without depressive symptoms. Future studies are needed to identify additional predictors of antepartum suicidality, determine the appropriate duration of reporting period for suicidal ideation screening, and assess the percentage of individuals with positive responses to the two suicidal ideation items at high risk of planning and attempting suicide.
Nguyen, Thinh N; Faulkner, Deb; Allen, Suzanna; Hauck, Yvonne L; Frayne, Jacqueline; Rock, Daniel; Rampono, Jonathan
2010-11-01
To examine the course of depressive and anxiety symptoms using serial measurements of the Edinburgh Postnatal Depression Scale (EPDS) in pregnant women with serious mental illness (SMI) attending a specialist multi-disciplinary antenatal clinic in Perth, Western Australia. A retrospective review of case notes was undertaken for 48 Western Australian pregnant women with schizophrenia and related psychoses and bipolar affective disorders who attended the Childbirth and Mental Illness (CAMI) antenatal clinic between December 2007 and November 2009. Of these patients, 27 completed the EPDS at booking (first appointment) and at 32 weeks gestation. Additional variables collected were demographic data, gestation at booking, and attendance rates for these 27 women, and for comparison another 21 women who did not complete the EPDS for one or both screening periods. Mean total EPDS score decreased from 12.2 (SD 7.6) at booking to 8.5 (SD 6.4) at 32 weeks gestation (p = 0.007). Overall mean attendance rates and number of appointments were similar to the non-SMI population and in keeping with standard guidelines. We speculate from these preliminary findings that being managed by a consistent small multi-disciplinary team and knowing that they will be supported throughout their pregnancy could lead to improvement of anxiety and depressive symptoms in pregnant women with SMI, and has the potential to increase their attendance for antenatal care.
Darwin, Zoe; McGowan, Linda; Edozien, Leroy C
2016-02-01
Antenatal mental health assessment is increasingly common in high-income countries. Despite lacking evidence on validation or acceptability, the Whooley questions (modified PHQ-2) and Arroll 'help' question are used in the UK at booking (the first formal antenatal appointment) to identify possible cases of depression. This study investigated validation of the questions and women's views on assessment. Women (n = 191) booking at an inner-city hospital completed the Whooley and Arroll questions as part of their routine clinical care then completed a research questionnaire containing the Edinburgh postnatal depression scale (EPDS). A purposive subsample (n = 22) were subsequently interviewed. The Whooley questions 'missed' half the possible cases identified using the EPDS (EPDS threshold ≥ 10: sensitivity 45.7 %, specificity 92.1 %; ≥ 13: sensitivity 47.8 %, specificity 86.1 %), worsening to nine in ten when adopting the Arroll item (EPDS ≥ 10: sensitivity 9.1 %, specificity 98.2 %; ≥ 13: sensitivity 9.5 %, specificity 97.1 %). Women's accounts indicated that under-disclosure relates to the context of assessment and perceived relevance of depression to maternity services. Depression symptoms are under-identified in current local practice. While validated tools are needed that can be readily applied in routine maternity care, psychometric properties will be influenced by the context of disclosure when implemented in practice.
Cataphoretic assembly of cationic dyes and deposition of carbon nanotube and graphene films.
Su, Y; Zhitomirsky, I
2013-06-01
Cathodic electrophoretic deposition (EPD) method has been developed for the fabrication of thin films from aqueous solutions of crystal violet (CV) dyes. The films contained rod-like particles with a long axis oriented perpendicular to the substrate surface. The proposed deposition mechanism involved cataphoresis of cationic CV(+) species, base generation in the cathodic reactions, and charge neutralization at the electrode surface. The assembly of rod-like particles was governed by π-π interactions of polyaromatic CV molecules. The deposition kinetics was studied by quartz crystal microbalance. CV dyes allowed efficient dispersion of multiwalled carbon nanotubes (MWCNTs) and graphene in water at relatively low CV concentrations. The feasibility of cathodic EPD of MWCNT and graphene from aqueous suspensions, containing CV, has been demonstrated. The deposition yield was investigated at different CV concentrations and deposition voltages. The relatively high deposition yield of MWCNT and graphene indicated that CV is an efficient dispersing, charging, and film forming agent for EPD. Electron microscopy data showed that at low CV concentrations in MWCNT or graphene suspensions and low deposition voltages, the films contained mainly MWCNT or graphene. The increase in the CV concentration and/or deposition voltage resulted in enhanced co-deposition of CV. The EPD method developed in this investigation paves the way for the fabrication of advanced nanocomposites by cathodic electrodeposition. Copyright © 2013 Elsevier Inc. All rights reserved.
Directed self-assembly of metal oxide quantum dots: Copper oxide on strontium titanium trioxide
NASA Astrophysics Data System (ADS)
Du, Yingge
2007-12-01
This dissertation explores the use of focused ion-beams (FIB) to direct the self-assembly of Cu2O quantum dots (QDs) on SrTiO3 (100) substrates via point implants of Ga+ at 30 keV After Ga+ implant and subsequent chemical and thermal surface preparation, oxygen plasma-assisted molecular beam-epitaxy (OPA-MBE) is used to grow Cu 2O QDs. The research of this dissertation finds that, for high FIB implant dose (5.6x1018 ions/cm2) and large interdot spacing (1000 nm), multiple QDs can be formed preferentially on the edges of FIB modified pits. For lower doses and/or smaller interdot spacings (8.8x1014 ions/cm2 and lower, 130 or 167 nm), individual QDs nucleate first within the pits. Under carefully controlled conditions, the separation and arrangement of the Cu2O QDs follows the FIB patterned template. This study finds that the FIB directed self-assembly technique works for different FIB doses, FIB interdot spacings and OPA-MBE deposition thicknesses, suggesting that this method is robust and flexible. Examination of QD growth on low-dose implant surfaces revealed a multi-step growth process. Initial deposition filled the pits just to the level of the original unmodified crystal growth surface. Following a pause in QD growth and the deposition of additional material, QD growth resumed on top of these perfectly filled pits. As growth continued, the dots reached a self-limiting size such that additional material deposition generated more QDs of similar size rather than continued growth of the large dots. This dissertation also seeks to increase understanding of the relative rolls played in the directed self-assembly process by local substrate chemistry, surface morphology, crystal-linity, and stress/strain. Experimental results revealed that although Ga concentration was noticeably higher on modified regions after FIB implant, no measurable Ga was found on the surface after high temperature annealing performed prior to QD growth. Thus Ga related chemistry/reactivity changes appear unlikely to be primary motivators of directed self-assembly. Low dose implant patterning created local depressions on the surface. This pit shape topography appears to be a strong contributor to the preferred nucleation within the pits, as the sidewalls of those surface pits could contain a high density of surface steps, which are known to decrease the adatom diffusion length and act as sinks to absorb the diffusing species. To further interpret the low dose implant results, calculations of total free-energy changes have been performed to study the differences between nucleation on a flat substrate surface and nucleation within a surface pit. This analysis shows that nucleation within a pit is almost always energetically favorable. In some special cases, assuming the pits have an inverted pyramidal shape, calculations show that island formation within the pits lowers the system total free-energy from the beginning of growth, i.e. there is no critical radius or energy barrier before a stable nucleus can be formed. The major geometric difference between high and low dose implantation area was revealed by AFM studies, which showed that pits generated by high implantation dose were still rounded after annealing and before growth, while pits from lower doses patterning had developed square edges oriented along the <100> directions of the substrate. These geometric differences suggest differences in crystalline or strain/stress states, either/both of which could have caused the subsequent different island growth characteristics. Continued study of directed self-assembly of metal oxide quantum dots should lead to better understanding of the creation of well ordered, precisely controlled, high density QD arrays, ultimately contributing to the development of next generation nanoelectronic, magnetic, and optical devices.
Stabilization of green bodies via sacrificial gelling agent during electrophoretic deposition
Worsley, Marcus A.; Kuntz, Joshua D.; Rose, Klint A.
2016-03-22
In one embodiment, a method for electrophoretic deposition of a three-dimensionally patterned green body includes suspending a first material in a gelling agent above a patterned electrode of an electrophoretic deposition (EPD) chamber, and gelling the suspension while applying a first electric field to the suspension to cause desired patterning of the first material in a resulting gelation. In another embodiment, a ceramic, metal, or cermet includes a plurality of layers, wherein each layer includes a gradient in composition, microstructure, and/or density in an x-y plane oriented parallel to a plane of deposition of the plurality of layers along a predetermined distance in a z-direction perpendicular to the plane of deposition.
Motowidlo, Leszek R.; Lee, P. J.; Tarantini, C.; ...
2017-11-28
We report on the development of multifilamentary Nb 3Sn superconductors by a versatile powder-in-tube technique (PIT) that demonstrates a simple pathway to a strand with a higher density of flux-pinning sites that has the potential to increase critical current density beyond present levels. The approach uses internal oxidation of Zr-alloyed Nb tubes to produce Zr oxide particles within the Nb 3Sn layer that act as a dispersion of artificial pinning centres (APCs). In this design, SnO 2 powder is mixed with Cu 5Sn 4 powder within the PIT core that supplies the Sn for the A15 reaction with Nb1Zr filamentmore » tubes. Initial results show an average grain size of ~38 nm in the A15 layer, compared to the 90–130 nm of typical APC-free high-J c strands made by conventional PIT or Internal Sn processing. Furthermore, there is a shift in the peak of the pinning force curve from H/H irr of ~0.2 to ~0.3 and the pinning force curves can be deconvoluted into grain boundary and point-pinning components, the point-pinning contribution dominating for the APC Nb-1wt%Zr strands.« less
NASA Astrophysics Data System (ADS)
Motowidlo, L. R.; Lee, P. J.; Tarantini, C.; Balachandran, S.; Ghosh, A. K.; Larbalestier, D. C.
2018-01-01
We report on the development of multifilamentary Nb3Sn superconductors by a versatile powder-in-tube technique (PIT) that demonstrates a simple pathway to a strand with a higher density of flux-pinning sites that has the potential to increase critical current density beyond present levels. The approach uses internal oxidation of Zr-alloyed Nb tubes to produce Zr oxide particles within the Nb3Sn layer that act as a dispersion of artificial pinning centres (APCs). In this design, SnO2 powder is mixed with Cu5Sn4 powder within the PIT core that supplies the Sn for the A15 reaction with Nb1Zr filament tubes. Initial results show an average grain size of ˜38 nm in the A15 layer, compared to the 90-130 nm of typical APC-free high-J c strands made by conventional PIT or Internal Sn processing. There is a shift in the peak of the pinning force curve from H/H irr of ˜0.2 to ˜0.3 and the pinning force curves can be deconvoluted into grain boundary and point-pinning components, the point-pinning contribution dominating for the APC Nb-1wt%Zr strands.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Motowidlo, Leszek R.; Lee, P. J.; Tarantini, C.
We report on the development of multifilamentary Nb 3Sn superconductors by a versatile powder-in-tube technique (PIT) that demonstrates a simple pathway to a strand with a higher density of flux-pinning sites that has the potential to increase critical current density beyond present levels. The approach uses internal oxidation of Zr-alloyed Nb tubes to produce Zr oxide particles within the Nb 3Sn layer that act as a dispersion of artificial pinning centres (APCs). In this design, SnO 2 powder is mixed with Cu 5Sn 4 powder within the PIT core that supplies the Sn for the A15 reaction with Nb1Zr filamentmore » tubes. Initial results show an average grain size of ~38 nm in the A15 layer, compared to the 90–130 nm of typical APC-free high-J c strands made by conventional PIT or Internal Sn processing. Furthermore, there is a shift in the peak of the pinning force curve from H/H irr of ~0.2 to ~0.3 and the pinning force curves can be deconvoluted into grain boundary and point-pinning components, the point-pinning contribution dominating for the APC Nb-1wt%Zr strands.« less
Local electronic and optical behaviors of a-plane GaN grown via epitaxial lateral overgrowth
NASA Astrophysics Data System (ADS)
Moore, J. C.; Kasliwal, V.; Baski, A. A.; Ni, X.; Özgür, Ü.; Morkoç, H.
2007-01-01
Conductive atomic force microscopy and near-field optical microscopy (NSOM) were used to study the morphology, conduction, and optical properties of a-plane GaN films grown via epitaxial lateral overgrowth (ELO) by metal organic chemical vapor deposition. The AFM images for the coalesced ELO films show undulations, where the window regions appear as depressions with a high density of surface pits. At reverse bias below 12V, very low uniform conduction (2pA) is seen in the window regions. Above 20V, a lower-quality sample shows localized sites inside the window regions with significant leakage, indicating a correlation between the presence of surface pits and leakage sites. Room temperature NSOM studies explicitly showed enhanced optical quality in the wing regions of the overgrown GaN due to a reduced density of dislocations, with the wings and the windows clearly discernible from near-field photoluminescence mapping.
NASA Technical Reports Server (NTRS)
Natesh, R.; Mena, M.; Plichta, M.; Smith, J. M.; Sellani, M. A.
1982-01-01
One hundred ninety-three silicon sheet samples, approximately 880 square centimeters, were analyzed for twin boundary density, dislocation pit density, and grain boundary length. One hundred fifteen of these samples were manufactured by a heat exchanger method, thirty-eight by edge defined film fed growth, twenty-three by the silicon on ceramics process, and ten by the dendritic web process. Seven solar cells were also step-etched to determine the internal defect distribution on these samples. Procedures were developed or the quantitative characterization of structural defects such as dislocation pits, precipitates, twin & grain boundaries using a QTM 720 quantitative image analyzing system interfaced with a PDP 11/03 mini computer. Characterization of the grain boundary length per unit area for polycrystalline samples was done by using the intercept method on an Olympus HBM Microscope.
Anopheles culicifacies in Baluchistan, Iran.
Zaim, M; Manouchehri, A V; Motabar, M; Emadi, A M; Nazari, M; Pakdad, K; Kayedi, M H; Mowlaii, G
1995-04-01
Anopheles culicifacies (probably species A) is the main vector of malaria in Baluchistan, southeastern Iran. Adult mosquitoes were collected during 1990-92 by five methods of sampling: knock-down pyrethrum space-spray indoors, human and animal bait (18.00-05.00 hours), pit shelters and CDC light traps, yielding 62%, 3%, 6%, 4% and 25% of specimens, respectively. Whereas spray-catches comprised c. 70% gravid and semi-gravid females, light trap catches were mostly (c. 60%) unfed females, while females from pit shelters comprised all abdominal stages more equally (13-36%). An.culicifacies populations peaked in April-May and rose again during August-November. Densities of indoor-resting mosquitoes were consistently greater in an unsprayed village than in villages subjected to residual house-spraying with propoxur, malathion or pirimiphos-methyl. Monthly malaria incidence generally followed fluctuations of An.culicifacies density, usually with a peak in May-June.
Bioerosion by pit-forming, temperate-reef sea urchins: History, rates and broader implications.
Russell, Michael P; Gibbs, Victoria K; Duwan, Emily
2018-01-01
Sea urchins are dominant members of rocky temperate reefs around the world. They often occur in cavities within the rock, and fit so tightly, it is natural to assume they sculpted these "pits." However, there are no experimental data demonstrating they bore pits. If they do, what are the rates and consequences of bioerosion to nearshore systems? We sampled purple sea urchins, Strongylocentrotus purpuratus, from sites with four rock types, three sedimentary (two sandstones and one mudstone) and one metamorphic (granite). A year-long experiment showed urchins excavated depressions on sedimentary rocks in just months. The rate of pit formation varied with rock type and ranged from <5 yr for medium-grain sandstone to >100 yr for granite. In the field, there were differences in pit size and shapes of the urchins (height:diameter ratio). The pits were shallow and urchins flatter at the granite site, and the pits were deeper and urchins taller at the sedimentary sites. Although overall pit sizes were larger on mudstone than on sandstone, urchin size accounted for this difference. A second, short-term experiment, showed the primary mechanism for bioerosion was ingestion of the substratum. This experiment eliminated potential confounding factors of the year-long experiment and yielded higher bioerosion rates. Given the high densities of urchins, large amounts of rock can be converted to sediment over short time periods. Urchins on sandstone can excavate as much as 11.4 kg m-2 yr-1. On a broader geographic scale, sediment production can exceed 100 t ha-1 yr-1, and across their range, their combined bioerosion is comparable to the sediment load of many rivers. The phase shift between urchin barrens and kelp bed habitats in the North Pacific is controlled by the trophic cascade of sea otters. By limiting urchin populations, these apex predators also may indirectly control a substantial component of coastal rates of bioerosion.
Bioerosion by pit-forming, temperate-reef sea urchins: History, rates and broader implications
Gibbs, Victoria K.; Duwan, Emily
2018-01-01
Sea urchins are dominant members of rocky temperate reefs around the world. They often occur in cavities within the rock, and fit so tightly, it is natural to assume they sculpted these “pits.” However, there are no experimental data demonstrating they bore pits. If they do, what are the rates and consequences of bioerosion to nearshore systems? We sampled purple sea urchins, Strongylocentrotus purpuratus, from sites with four rock types, three sedimentary (two sandstones and one mudstone) and one metamorphic (granite). A year-long experiment showed urchins excavated depressions on sedimentary rocks in just months. The rate of pit formation varied with rock type and ranged from <5 yr for medium-grain sandstone to >100 yr for granite. In the field, there were differences in pit size and shapes of the urchins (height:diameter ratio). The pits were shallow and urchins flatter at the granite site, and the pits were deeper and urchins taller at the sedimentary sites. Although overall pit sizes were larger on mudstone than on sandstone, urchin size accounted for this difference. A second, short-term experiment, showed the primary mechanism for bioerosion was ingestion of the substratum. This experiment eliminated potential confounding factors of the year-long experiment and yielded higher bioerosion rates. Given the high densities of urchins, large amounts of rock can be converted to sediment over short time periods. Urchins on sandstone can excavate as much as 11.4 kg m-2 yr-1. On a broader geographic scale, sediment production can exceed 100 t ha-1 yr-1, and across their range, their combined bioerosion is comparable to the sediment load of many rivers. The phase shift between urchin barrens and kelp bed habitats in the North Pacific is controlled by the trophic cascade of sea otters. By limiting urchin populations, these apex predators also may indirectly control a substantial component of coastal rates of bioerosion. PMID:29466357
Ngai, Fei-Wan; Wong, Paul Wai-Ching; Leung, Kwok-Yin; Chau, Pui-Hing; Chung, Ka-Fai
2015-01-01
Cognitive-behavioral therapy (CBT) is one of the most effective interventions for postnatal depression. However, few studies have evaluated the effect of CBT delivered via telephone for newborn mothers. The purpose of this study was to evaluate the efficacy of telephone-based CBT for postnatal depression at 6 weeks and 6 months postpartum. A multisite randomized controlled trial was conducted in the postnatal units at 3 regional hospitals in Hong Kong. A total of 397 women with an Edinburgh Postnatal Depression Scale (EPDS) score ≥10 on the second or third day postpartum were randomized to receive telephone-based CBT (n = 197) or standard care (n = 200). Primary outcome was the total EPDS score. A cutoff score of 9/10 on the EPDS was used to define women at risk of postnatal depression. Telephone-based CBT was associated with significantly lower depressive symptoms compared with standard care, when assessed at 6 weeks postpartum in the subgroups of mothers with minor depression (EPDS 10-12; difference = 1.90, 95% CI: 0.72-3.08; p = 0.002) and major depression (EPDS ≥13; difference = 5.00, 95% CI: 3.12-6.88; p < 0.001). The effect was sustained at 6 months postpartum in the subgroup with minor depression (difference = 1.20, 95% CI: 0.09-2.32; p = 0.034) but not significant in the subgroup with major depression (difference = 1.69, 95% CI: -0.10-3.47; p = 0.064). The proportion of women who satisfied our definition of postnatal depression was significantly lower in the intervention group at 6 weeks (difference = 23.3%, 95% CI: 13.7-33.0%; p < 0.001) and 6 months postpartum (difference = 11.4%, 95% CI: 1.9-20.8%; p = 0.019). Telephone-based CBT produced a significantly greater reduction in depressive symptoms than standard care during the postpartum period. © 2015 S. Karger AG, Basel.
Heterogeneity of postpartum depression: a latent class analysis
2016-01-01
Summary Background Maternal depression in the postpartum period confers substantial morbidity and mortality, but the definition of postpartum depression remains controversial. We investigated the heterogeneity of symptoms with the aim of identifying clinical subtypes of postpartum depression. Methods Data were aggregated from the international perinatal psychiatry consortium Postpartum Depression: Action Towards Causes and Treatment, which represents 19 institutions in seven countries. 17 912 unique subject records with phenotypic data were submitted. We applied latent class analyses in a two-tiered approach to assess the validity of empirically defined subtypes of postpartum depression. Tier one assessed heterogeneity in women with complete data on the Edinburgh postnatal depression scale (EPDS) and tier two in those with postpartum depression case status. Findings 6556 individuals were assessed in tier one and 4245 in tier two. A final model with three latent classes was optimum for both tiers. The most striking characteristics associated with postpartum depression were severity, timing of onset, comorbid anxiety, and suicidal ideation. Women in class 1 had the least severe symptoms (mean EPDS score 10·5), followed by those in class 2 (mean EPDS score 14·8) and those in class 3 (mean EPDS score 20·1). The most severe symptoms of postpartum depression were significantly associated with poor mood (mean EPDS score 20·1), increased anxiety, onset of symptoms during pregnancy, obstetric complications, and suicidal ideation. In class 2, most women (62%) reported symptom onset within 4 weeks postpartum and had more pregnancy complications than in other two classes (69% vs 67% in class 1 and 29% in class 3). Interpretation PPD seems to have several distinct phenotypes. Further assessment of PPD heterogeneity to identify more precise phenotypes will be important for future biological and genetic investigations. Funding Sources of funding are listed at the end of the article. PMID:26359613
Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes.
Lin, He; Yao, Chao; Zhang, Xianping; Zhang, Haitao; Wang, Dongliang; Zhang, Qianjun; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo
2014-03-25
Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 10(4) A/cm(2) in 10 T and 4.3 × 10(4) A/cm(2) in 14 T at 4.2 K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications.
Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes
Lin, He; Yao, Chao; Zhang, Xianping; Zhang, Haitao; Wang, Dongliang; Zhang, Qianjun; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo
2014-01-01
Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 104 A/cm2 in 10 T and 4.3 × 104 A/cm2 in 14 T at 4.2 K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications. PMID:24663054
Strongly enhanced current densities in Sr0.6K0.4Fe2As2 + Sn superconducting tapes
NASA Astrophysics Data System (ADS)
Lin, He; Yao, Chao; Zhang, Xianping; Zhang, Haitao; Wang, Dongliang; Zhang, Qianjun; Ma, Yanwei; Awaji, Satoshi; Watanabe, Kazuo
2014-03-01
Improving transport current has been the primary topic for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based tapes is one of the important reasons for low critical current density (Jc) values. In this work, the superconducting core density of ex-situ Sr0.6K0.4Fe2As2 + Sn tapes, prepared from optimized precursors, was significantly improved by employing a simple hot pressing as an alternative route for final sintering. The resulting samples exhibited optimal critical temperature (Tc), sharp resistive transition, small resistivity and high Vickers hardness (Hv) value. Consequently, the transport Jc reached excellent values of 5.1 × 104 A/cm2 in 10 T and 4.3 × 104 A/cm2 in 14 T at 4.2 K, respectively. Our tapes also exhibited high upper critical field Hc2 and almost field-independent Jc. These results clearly demonstrate that PIT pnictide wire conductors are very promising for high-field magnet applications.
Walrus foraging marks on the seafloor in Bristol Bay, Alaska: A reconnaissance survey
Bornhold, Brian D.; Jay, Chadwick V.; McConnaughey, Robert; Rathwell, Glenda; Rhynas, Karl; Collins, William
2005-01-01
A reconnaissance sidescan sonar survey in Bristol Bay, Alaska revealed extensive areas of seafloor with features related to walrus foraging. They are similar to those seen in areas such as the outer Bering Sea and Chukchi Sea. Two types of feature were observed: (a) small (≪1 m diameter) shallow pits, often in clusters ranging in density from 5 pits per hectare to 35 pits per hectare; and, (b) more abundant, narrow, sinuous furrows, typically 5 to 10 m long with some reaching 20 m or more. Most foraging marks were in less than 60 m water depth in areas of sandy seafloor that were smooth, hummocky or characterized by degraded bedforms; the absence of foraging marks in other areas may be related, in part, to their more dynamic nature. The distribution of foraging marks was consistent in a general way with walrus locations from satellite telemetry studies.
Results from Preliminary Checks on AmBe Neutron Source Number 71
2011-02-01
radiation and additional lead shielding was used to shield against gamma radiation emissions. Electronic dosimeters , the MGP DMC2000GN and Thermo EPD...DMC2000GN (S/N: 007395) and EPD-N2 (S/N: 07106323) electronic dosimeters were employed as these both are able to measure and record gamma and neutron...the AN/VDR-2 gamma radiation meter and Meridian Model 5085 neutron meter to confirm this and electronic dosimeters would be worn by personnel to
The Savannah River Site`s Groundwater Monitoring Program: Third quarter 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rogers, C.D.
1993-02-04
The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site`s (SRS) Groundwater Monitoring Program. During third quarter 1992, EPD/EMS conducted extensive sampling of monitoring wells. Table 1 lists those well series with constituents in the groundwater above Flag 2 during third quarter 1992, organized by location. Results from all laboratory analyses are used to generate this table. Specific conductance and pH data from the field also are included in this table.
Greywater Disposal Practices in Northern Botswana—The Silent Spring?
Alexander, Kathleen A.; Godrej, Adil
2015-01-01
Disposal of greywater is a neglected challenge facing rapidly growing human populations. Here, we define greywater as wastewater that originates from household activities (e.g., washing dishes, bathing, and laundry) but excludes inputs from the toilet. Pollutants in greywater can include both chemical and biological contaminates that can significantly impact human, animal, and environmental health under certain conditions. We evaluate greywater disposal practices in nonsewered, low-income residential areas in Kasane (264 dwellings/ha), Kazungula (100 du/ha), and Lesoma (99 du/ha) villages in Northern Botswana through household surveys (n = 30 per village). Traditional pit latrines were the dominant form of sanitation (69%, n = 90, 95% CI, 59%–79%) while 14% of households did not have access to onsite sanitation (95% CI 0%–22%). While greywater disposal practices varied across villages, respondents in all sites reported dumping greywater into the pit latrine. Frequency varied significantly across villages with the highest level reported in Kasane, where residential density was greatest (p < 0.014, χ2 = 9.13, 61% (n = 23, 95% CI 41%–81%), Kazungula 41% (n = 22, 95% CI 20%–62%), Lesoma 13% (95% CI 0%–29%). Disposal of greywater in this manner was reported to limit contamination of the household compound and reduce odors, as well as pit latrine fecal levels. Some respondents reported being directed by local health authorities to dispose of greywater in this manner. Environmentally hazardous chemicals were also dumped directly into the pit latrine to reduce odors. With high household to pit latrine ratios particularly in rental properties (4.2 households, SD = 3.32, range = 15 units, average household size 5.3, SD = 4.4), these greywater and pit latrine management approaches can significantly alter hydraulic loading and leaching of chemicals, microorganisms, and parasites. This can dramatically expand the environmental footprint of pit latrines and greywater, increasing pollution of soil, ground, and surface water resources. Challenges in greywater disposal and pit latrines must be addressed with urgency as health behaviors directed at minimizing negative aspects may amplify the environmental impacts of both greywater and pit latrine excreta. PMID:26580640
Light scattering apparatus and method for determining radiation exposure to plastic detectors
Hermes, Robert E.
2002-01-01
An improved system and method of analyzing cumulative radiation exposure registered as pits on track etch foils of radiation dosimeters. The light scattering apparatus and method of the present invention increases the speed of analysis while it also provides the ability to analyze exposure levels beyond that which may be properly measured with conventional techniques. Dosimeters often contain small plastic sheets that register accumulated damage when exposed to a radiation source. When the plastic sheet from the dosimeter is chemically etched, a track etch foil is produced wherein pits or holes are created in the plastic. The number of these pits, or holes, per unit of area (pit density) correspond to the amount of cumulative radiation exposure which is being optically measured by the apparatus. To measure the cumulative radiation exposure of a track etch foil a high intensity collimated beam is passed through foil such that the pits and holes within the track etch foil cause a portion of the impinging light beam to become scattered upon exit. The scattered light is focused with a lens, while the primary collimated light beam (unscattered light) is blocked. The scattered light is focused by the lens onto an optical detector capable of registering the optical power of the scattered light which corresponds to the cumulative radiation to which the track etch foil has been exposed.
An improved driving waveform reference grayscale of electrophoretic displays
NASA Astrophysics Data System (ADS)
Wang, Li; Yi, Zichuan; Peng, Bao; Zhou, Guofu
2015-10-01
Driving waveform is an important component for gray scale display on the electrophoretic display (EPD). In the traditional driving waveform, a white reference gray scale is formed before writing a new image. However, the reflectance value can not reach agreement in each gray scale transformation. In this paper, a new driving waveform, which has a short waiting time after the formation of reference gray scale, is proposed to improve the consistency of reference gray scale. Firstly, the property of the particles in the microcapsule is analyzed and the change of the EPD reflectance after the white reference gray scale formation is studied. Secondly, the reflectance change curve is fitted by using polynomial and the duration of the waiting time is determined. Thirdly, a set of the new driving waveform is designed by using the rule of DC balance and some real E-ink commercial EPDs are used to test the performance. Experimental results show that the effect of the new driving waveform has a better performance than traditional waveforms.
Hartley, Chelsey M.; Barroso, Nicole; Rey, Yasmin; Pettit, Jeremy W.; Bagner, Daniel M.
2015-01-01
Background Although a number of studies have examined the factor structure of the Edinburgh Postnatal Depression Scale (EPDS) in predominately White or African American samples, no published research has reported on the factor structure among Hispanic women who reside in the United States. Objective The current study examined the factor structure of the EPDS among Hispanic mothers in the United States. Method Among 220 Hispanic women, drawn from a pediatric primary care setting, with an infant aged 0 to 10 months, 6 structural models guided by the empirical literature were evaluated using confirmatory factor analysis. Results Results supported a 2-factor model of depression and anxiety as the best fitting model. Multigroup models supported the factorial invariance across women who completed the EDPS in English and Spanish. Conclusion These findings provide initial support for the 2-factor structure of the EPDS among Hispanic women in the United States. PMID:24807217
Hartley, Chelsey M; Barroso, Nicole; Rey, Yasmin; Pettit, Jeremy W; Bagner, Daniel M
2014-12-01
Although a number of studies have examined the factor structure of the Edinburgh Postnatal Depression Scale (EPDS) in predominately White or African American samples, no published research has reported on the factor structure among Hispanic women who reside in the United States. The current study examined the factor structure of the EPDS among Hispanic mothers in the United States. Among 220 Hispanic women, drawn from a pediatric primary care setting, with an infant aged 0 to 10 months, 6 structural models guided by the empirical literature were evaluated using confirmatory factor analysis. Results supported a 2-factor model of depression and anxiety as the best fitting model. Multigroup models supported the factorial invariance across women who completed the EDPS in English and Spanish. These findings provide initial support for the 2-factor structure of the EPDS among Hispanic women in the United States. © 2014 Wiley Periodicals, Inc.
The efficacy of E.P.D., a new immunotherapy, in the treatment of allergic diseases in children.
Caramia, G; Franceschini, F; Cimarelli, Z A; Ciucchi, M S; Gagliardini, R; Ruffini, E
1996-11-01
A double blind study was made on a group of 35 children, 8 of whom were allergic to Grass and 27 allergic to Pteronyssinus and Farinae Dermatophagoides. We verified the efficacy and tolerability of a new immunotherapy called E.P.D. (Enzyme Potentiated Desensitization). This particular immunotherapy consists in an intradermal injection of a mix made up of an allergic solution at extremely low doses and an enzyme, beta-glucuronidase. The vaccine is administered once a year, two weeks before pollen peaks for children with seasonal allergies and two times a year, in February and November, for children with non-seasonal allergies (Dermatophagoides). The results, statistically analyzed on the basis of a symptoms score, showed good clinical efficacy in patients affected by both seasonal and non-seasonal allergies. Due to the clinical effectiveness, easy administration and excellent tolerability of the immunotherapy, E.P.D. is particularly suited for treating or reducing allergic symptoms in allergic children.
Di Stanislao, C; Di Berardino, L; Bianchi, I; Bologna, G
1997-02-01
Control of seasonal symptoms by means of a preventive and easy to use (only one intradermal injection eight weeks before the pollen peak) immunotherapy, is recommended nowadays. We verified the clinical efficacy of E.P.D. (Enzyme Potentiated Desensibilization) in a double-blind, placebo-controlled study. This particular immunotherapy consists of an intradermal injection mix, made up of allergenic extracts at extremely low doses and an enzyme called beta-glucuronidase. The vaccine is administered once a year, eight weeks before pollen peaks. We studied a group of 40 patients allergic to grass pollen. The results, analysed statistically on the basis of a symptoms score, showed good clinical efficacy and a significant reduction of drug consumption during the high pollen period. Due to the clinical effectiveness, easy administration (only on injection) and excellent tolerance of the immunotherapy, E.P.D. is particularly suited for the prevention of seasonal symptoms in patients allergic to grass pollen.
Smallegange, Renate C; Kelling, Frits J; Den Otter, Cornelis J
2008-12-01
Houseflies, Musca domestica, obtained from a high-larval-density culture were significantly (ca. 1.5 times) smaller than those from a low-larval-density culture. The same held true for their antennae and maxillary palps. Structure, number, and distribution of sensilla on antennae and palps of small and large flies were investigated using Scanning electron microscopy and Transmission electron microscopy. In each funiculus three pits were present, two (Type I) consisting of several compartments and one (Type II) of one compartment. Four types of olfactory sensilla were detected: trichoid sensilla on the funiculi, basiconic sensilla on funiculi and palps, grooved sensilla on funiculi and in pits Type I, and clavate sensilla on funiculi and in pits Type II. Type I pits also contained striated sensilla (presumably hygroreceptors). Mechanosensory bristles were present on scapes, pedicels, and palps. Noninnervated microtrichia were found on the palps and all antennal segments. The large houseflies possessed nearly twice as much sensilla as the small flies. So far, we did not observe differences in behavior between small and large flies. We assumed that small flies, being olfactory less equipped than large flies, may be able to compensate for this by, e.g., visual cues or by their olfactory sensilla being more sensitive than those of large flies. To be able to answer these questions careful studies have to be done on the behavioral responses of small and large flies to environmental stimuli. In addition, electrophysiological studies should be performed to reveal whether the responses of individual sensilla of flies reared under different conditions have been changed. 2008 Wiley-Liss, Inc.
Maternal postnatal depression and child growth: a European cohort study
2010-01-01
Background Previous studies have reported postpartum depression to be associated with both positive and negative effects on early infant growth. This study examined the hypothesis that maternal postnatal depression may be a risk factor for later child growth faltering or overweight. Methods A total of 929 women and their children participating in a European multicenter study were included at a median age of 14 days. Mothers completed the Edinburgh postnatal depression scale (EPDS) at 2, 3 and 6 months after delivery. EPDS scores of 13 and above at any time were defined as maternal depression. Weight, length, triceps and subscapular skinfold thicknesses were measured, and body mass index (BMI) were calculated when the children were two years old and converted to standard deviation scores based on the WHO Multicentre Growth Reference Study (MGRS). Results Z-scores for weight-for-length at inclusion of infants of mothers with high EPDS scores (-0.55, SD 0.74) were lower than of those with normal scores (-0.36, SD 0.74; p = 0.013). BMI at age 24 months did not differ in the high (16.3 kg/m2, SD 1.3) and in the normal EPDS groups (16.2 kg/m2, SD 1.3; p = 0.48). All other anthropometric indices also did not differ between groups, with no change by multivariate adjustment. Conclusions We conclude that a high maternal postnatal depression score does not have any major effects on offspring growth in high income countries. PMID:20226021
Martínez, Pablo; Vöhringer, Paul A.; Rojas, Graciela
2016-01-01
Objective to develop a predictive model to evaluate the factors that modify the access to treatment for Postpartum Depression (PPD). Methods prospective study with mothers who participated in the monitoring of child health in primary care centers. For the initial assessment and during 3 months, it was considered: sociodemographic data, gyneco-obstetric data, data on the services provided, depressive symptoms according to the Edinburgh Postpartum Depression Scale (EPDS) and quality of life according to the Short Form-36 Health Status Questionnaire (SF-36). The diagnosis of depression was made based on MINI. Mothers diagnosed with PPD in the initial evaluation, were followed-up. Results a statistical model was constructed to determine the factors that prevented access to treatment, which consisted of: item 2 of EPDS (OR 0.43, 95%CI: 0.20-0.93) and item 5 (OR 0.48, 95%CI: 0.21-1.09), and previous history of depression treatment (OR 0.26, 95%CI: 0.61-1.06). Area under the ROC curve for the model=0.79; p-value for the Hosmer-Lemershow=0.73. Conclusion it was elaborated a simple, well standardized and accurate profile, which advises that nurses should pay attention to those mothers diagnosed with PPD, presenting low/no anhedonia (item 2 of EPDS), scarce/no panic/fear (item 5 of EPDS), and no history of depression, as it is likely that these women do not initiate treatment. PMID:27027674
Gawlik, S; Waldeier, L; Müller, M; Szabo, A; Sohn, C; Reck, C
2013-04-01
There is a high prevalence of depression in Germany and all over the world. Maternal depressive symptoms during pregnancy have been shown in some studies to be associated with an increased risk of preterm birth and low birth weight. The influence of maternal depressive symptoms during pregnancy on preterm delivery and fetal birth weight was investigated in a prospective single-centre study. A sample of 273 healthy pregnant women was assessed for symptoms of antepartum depression. Symptoms were measured using the Edinburgh Postnatal Depression Scale (EPDS) and the Patient Health Questionnaire (PHQ). Symptoms of anxiety were assessed using the State/Trait Anxiety Inventory. Patients who scored above the cutoff were contacted by phone for a Structured Clinical Diagnostic interview. Neonatal measurements were obtained from the birth registry of the Department of Obstetrics. Baseline data were assessed with a self-styled data sheet. Prevalence of elevated depressive symptoms was 13.2% when measured with the EPDS and 8.4% with the PHQ. According to DSM-IV criteria, only four (EPDS) respective two (PHQ-D) of these patients could be diagnosed with a depressive disorder and ten (EPDS) respective seven (PHQ) with an anxiety disorder. There was no significant influence on preterm birth or birth weight. Maternal depressive symptoms are self-reported. Elevated subclinical symptoms of depression and anxiety during pregnancy are common. However, this study showed no evidence that these symptoms are associated with adverse pregnancy outcome.
Amir, Fatima Z.; Pham, V. H.; Mullinax, D. W.; ...
2016-06-07
Ruthenium oxide (RuO 2) nanomaterials exist as excellent materials for electrochemical capacitors. However, they tend to suffer from low mechanical flexibility when cast into films, which makes them unsuitable for flexible device applications. Herein, we report an environmentally friendly and solution-processable approach to fabricate RuO 2-based composite electrodes for flexible solid state supercapacitors. The composites were produced by anchoring RuO 2 nanoparticles onto holey reduced graphene oxide (HRGO) via a sol-gel method, followed by the electrophoretic deposition (EPD) of the material into thin films. The uniform anchoring of ultra-small RuO 2 nanoparticles on the two-dimensional HRGO sheets resulted in HRGO-RuOmore » 2 hybrid sheets with excellent mechanical flexibility of HRGO. EPD induced a layer-by-layer assembly mechanism for the HRGO-RuO 2 hybrid sheets, which resulted in a binder-free, flexible electrode. The obtained HRGO-RuO 2 flexible supercapacitors exhibited excellent electrochemical capacitive performance in a PVA-H 2SO 4 gel electrolyte with a specific capacitance of 418 F g -1 and superior cycling stability of 88.5% capacitance retention after 10,000 cycles. Additionally, these supercapacitors exhibited high rate performance with capacitance retention of 85% by increasing the current density from 1.0 to 20.0 Ag -1, and excellent mechanical flexibility with only 4.9% decay in the performance when bent 180°.« less
Pitting failure of copper pipings for emergency fire sprinkler in ground water
NASA Astrophysics Data System (ADS)
Baek, Seung-won; Lee, Jong-kwon; Kim, Jong-jip; Kim, Kyung-ja
2015-05-01
The possibility of microbiologically influenced corrosion was investigated in the early pitted copper pipes. The pipes were installed for less than 6 months as an immergency fire sprinkler. The bacteria were cultured by sampling of corrosion by-product near pits on failed copper pipes for the aerobic as well as anaerobic bacteria. However, only aerobic bacteria was found, which were Micrococcus Luteus and Bacillus sp.. The corrosion rate of copper pipes were studied by weight loss in the groundwater and polarization method. In immersion test as well as the electrochemical polarization test in ground water, only Micrococcus Luteus could activate corrosion of copper by 20% and 15%, respectively. On the other hand, Bacillus sp. showed little effect on corrosion in the above two tests. The shape and characteristics of failed copper pipes as well as simulated copper were investigated using stereoscope, optical microscopy, scanning electron microscope and EDS. The cause of pits were discussed, related with the dissolved copper concentrations, pH, and optical density. It could be concluded that the early failure of copper pipings could be ascribed to the acceration of copper in the presence of bacteria, i.e., Micrococcus Luteus.
Erosive Pustular Dermatosis of the Scalp with Urate-Like Crystals.
Emanuel, Patrick O; Paul, Sharad P
2017-01-01
Follicular urate-like crystals were first described in Necrotizing Infundibular Crystalline Folliculitis (NICF), a rare cutaneous disorder with multiple waxy folliculocentric papules. Similar crystal accumulation may be seen within follicular infundibulae as an incidental finding. We describe a case showing identical crystals occurring within the horn-like crusts of a patient with erosive pustular dermatosis of the scalp (EPDS), a condition which due to its presentation can often be mistaken for nonmelanoma skin cancer. A brief overview of erosive pustular dermatosis of the scalp (EPDS) is presented in this paper.
NASA Astrophysics Data System (ADS)
Togano, Kazumasa; Gao, Zhaoshun; Matsumoto, Akiyoshi; Kumakura, Hiroaki
2013-11-01
We report that the transport critical current density Jc of ex situ powder-in-tube (PIT) processed (Ba, K)Fe2As2 (Ba-122) tapes can be significantly enhanced by applying uniaxial cold pressing at the final stage of deformation. The tapes were prepared by packing high quality precursor powder into a Ag tube, cycles of rolling and intermediate annealing, and pressing followed by the final heat treatment for sintering. The Jc values in applied magnetic fields were increased by almost one order of magnitude compared to the tapes processed without pressing, exceeding 104 A cm-2 at 4.2 K. We achieved the highest Jc (at 4.2 K and 10 T) of 2.1×104 A cm-2 among PIT-processed Fe-based wires and tapes reported so far. The Jc-H curves measured at higher temperatures maintain small field dependence up to around 20 K, suggesting that these tapes are promising for applications at higher temperatures as well as at liquid helium temperature. The microstructure investigations reveal that there are two possible causes of the large Jc enhancement by pressing: one is densification and the other is the change of crack structure. Optimization of processing parameters such as the reduction ratio of rolling and pressing is expected to yield further Jc enhancement.
NASA Astrophysics Data System (ADS)
Raleigh, M. S.; Smyth, E.; Small, E. E.
2017-12-01
The spatial distribution of snow water equivalent (SWE) is not sufficiently monitored with either remotely sensed or ground-based observations for water resources management. Recent applications of airborne Lidar have yielded basin-wide mapping of SWE when combined with a snow density model. However, in the absence of snow density observations, the uncertainty in these SWE maps is dominated by uncertainty in modeled snow density rather than in Lidar measurement of snow depth. Available observations tend to have a bias in physiographic regime (e.g., flat open areas) and are often insufficient in number to support testing of models across a range of conditions. Thus, there is a need for targeted sampling strategies and controlled model experiments to understand where and why different snow density models diverge. This will enable identification of robust model structures that represent dominant processes controlling snow densification, in support of basin-scale estimation of SWE with remotely-sensed snow depth datasets. The NASA SnowEx mission is a unique opportunity to evaluate sampling strategies of snow density and to quantify and reduce uncertainty in modeled snow density. In this presentation, we present initial field data analyses and modeling results over the Colorado SnowEx domain in the 2016-2017 winter campaign. We detail a framework for spatially mapping the uncertainty in snowpack density, as represented across multiple models. Leveraging the modular SUMMA model, we construct a series of physically-based models to assess systematically the importance of specific process representations to snow density estimates. We will show how models and snow pit observations characterize snow density variations with forest cover in the SnowEx domains. Finally, we will use the spatial maps of density uncertainty to evaluate the selected locations of snow pits, thereby assessing the adequacy of the sampling strategy for targeting uncertainty in modeled snow density.
Dompierre, Kathryn A; Barbour, S Lee
2016-06-01
Soft tailings pose substantial challenges for mine reclamation due to their high void ratios and low shear strengths, particularly for conventional terrestrial reclamation practices. Oil sands mine operators have proposed the development of end pit lakes to contain the soft tailings, called fluid fine tailings (FFT), generated when bitumen is removed from oil sands ore. End pit lakes would be constructed within mined-out pits with FFT placed below the lake water. However, the feasibility of isolating the underlying FFT has yet to be fully evaluated. Chemical constituents of interest may move from the FFT into the lake water via two key processes: (1) advective-diffusive mass transport with upward pore water flow caused by settling of the FFT; and (2) mixing created by wind events or unstable density profiles through the lake water and upper portion of the FFT. In 2013 and 2014, temperature and stable isotopes of water profiles were measured through the FFT and lake water in the first end pit lake developed by Syncrude Canada Ltd. Numerical modelling was undertaken to simulate these profiles to identify the key mechanisms controlling conservative mass transport in the FFT. Shallow mixing of the upper 1.1 m of FFT with lake water was required to explain the observed temperature and isotopic profiles. Following mixing, the re-establishment of both the temperature and isotope profiles required an upward advective flux of approximately 1.5 m/year, consistent with average FFT settling rates measured at the study site. These findings provide important insight on the ability to sequester soft tailings in an end pit lake, and offer a foundation for future research on the development of end pit lakes as an oil sands reclamation strategy. Copyright © 2016 Elsevier B.V. All rights reserved.
Burkholder, David; Hadi, Duraid; Kunnavakkam, Rangesh; Kindler, Hedy; Todd, Kristy; Celauro, Amy Durkin; Vigneswaran, Wickii T
2015-05-01
Maximal cytoreductive surgeries--extrapleural pneumonectomy and extended pleurectomy and decortication (EPD)--are effective surgical treatments in selected patients with malignant pleural mesothelioma. Extended pleurectomy and decortication results in equivalent survival yet better health-related quality of life (HRQoL). Patients with malignant pleural mesothelioma were studied for the effects of EPD on HRQoL and pulmonary function. The European Organization for Research and Treatment of Cancer Core Quality of Life Questionaire-C30 was used to evaluate HRQoL before operation, and at 4 to 5 and 7 to 8 months postoperatively. Pulmonary function tests were measured immediately before and 5 to 7 months after the operation. Patients were compared according to World Health Organization baseline performance status (PS). Of the 36 patients enrolled, 17 were PS 0 and 19 were PS 1 or PS 2 at baseline. Patients in groups PS 1 and PS 2 had significantly worse global health, functional, and symptoms scores. After EPD, PS 0 patients had no change in global health or function and symptoms scores except for emotional function, whereas PS 1 or PS 2 patients showed improvements at 4 to 5 months with further improvements at 7 to 8 months. The PS 0 patients demonstrated a significant decrease in forced vital capacity (p = 0.001), forced expiratory volume in 1 second (p = 0.002), total lung capacity (p = 0.0006) and diffusing capacity of the lung for carbon monoxide (p = 0.003) after EPD, whereas no change was observed in PS 1 and PS 2 patients. Extended pleurectomy and decortication did not improve overall HRQoL and had a negative impact in pulmonary function in minimally symptomatic patients. In symptomatic patients, a significant improvement in HRQoL was observed after EPD, which continued at late follow-up, although the pulmonary function was not affected. As changes in HRQoL are multidimensional, the preservation of the pulmonary function may have contributed to the net benefit observed in PS 1 and PS 2 patients. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Mahmud, Wan Mohd. Rushidi Wan; Awang, Amir; Mohamed, Mahmood Nazar
2003-01-01
Aim: To reevaluate the psychometric characteristics of the Malay version of the Edinburgh Postnatal Depression Scale among a sample of postpartum Malay women attending the Bakar Bata Health Center in Alor Setar, Kedah, North West of Peninsular Malaysia. Materials and methods: 64 women between 4 to 12 weeks postpartum were recruited for there validation study. They were given questionnaires on socio-demography, the 21-item Malay version of the Beck Depression Inventory II (BDI-II) and the 10-item Malay version of the Edinburgh Postnatal Depression Scale (EPDS). All the participants were later interviewed using the Hamilton Depression Rating Scale (HDRS-17) and the Composite International Diagnostic Interview (CIDI). All diagnoses were made based on the Tenth Edition of the International Classification of Diseases (ICD-10) Results: 9 women (14.1%) were diagnosed to have significant depression (7 mild depressive episodes and 2 moderate depressive episodes according to ICD-10). EPDS was found to have good internal consistency (Cronbach alpha =0.86) and split half reliability (Spearman split half coefficient = 0.83). The instrument also showed satisfactory discriminant and concurrent validity as evidenced by the statistically significant difference in EPDS scores between the depressed group and their non-depressed counterparts (Mann Whitney U test: 2 tailed p value < 0.01) and good correlations between the instrument and both the Malay version of BDI-II and the HRDS-17 (Spearman rank correlation coefficients of 0.78 and 0.88 respectively). At the 11/12 cut-off score the sensitivity of the EPDS is 100%, with a specificity of 98.18%, positive predictive value of 90%, negative predictive value of 100 % and misclassification rate of 1.56%. Conclusion: This study confirmed the reliability and validity of the Malay version of the Edinburgh Postnatal Depression Scale in identifying postpartum depression among recently delivered Malay women attending the Bata Bata Health Center in Alor Setar, Kedah, North West of Peninsular Malaysia. PMID:23386800
Marcano-Belisario, José S; Gupta, Ajay K; O'Donoghue, John; Ramchandani, Paul; Morrison, Cecily; Car, Josip
2017-05-10
Mobile devices may facilitate depression screening in the waiting area of antenatal clinics. This can present implementation challenges, of which we focused on survey layout and technology deployment. We assessed the feasibility of using tablet computers to administer a socio-demographic survey, the Whooley questions and the Edinburgh Postnatal Depression Scale (EPDS) to 530 pregnant women attending National Health Service (NHS) antenatal clinics across England. We randomised participants to one of two layout versions of these surveys: (i) a scrolling layout where each survey was presented on a single screen; or (ii) a paging layout where only one question appeared on the screen at any given time. Overall, 85.10% of eligible pregnant women agreed to take part. Of these, 90.95% completed the study procedures. Approximately 23% of participants answered Yes to at least one Whooley question, and approximately 13% of them scored 10 points of more on the EPDS. We observed no association between survey layout and the responses given to the Whooley questions, the median EPDS scores, the number of participants at increased risk of self-harm, and the number of participants asking for technical assistance. However, we observed a difference in the number of participants at each EPDS scoring interval (p = 0.008), which provide an indication of a woman's risk of depression. A scrolling layout resulted in faster completion times (median = 4 min 46 s) than a paging layout (median = 5 min 33 s) (p = 0.024). However, the clinical significance of this difference (47.5 s) is yet to be determined. Tablet computers can be used for depression screening in the waiting area of antenatal clinics. This requires the careful consideration of clinical workflows, and technology-related issues such as connectivity and security. An association between survey layout and EPDS scoring intervals needs to be explored further to determine if it corresponds to a survey layout effect. Future research needs to evaluate the effect of this type of antenatal depression screening on clinical outcomes and clinic workflows. This study was registered in ClinicalTrials.gov under the identifier NCT02516982 on 20 July 2015.
Cooke, Margaret; Schmied, Virginia; Sheehan, Athena
2007-03-01
To explore the relationships between maternal distress, breast feeding cessation, breast feeding problems and breast feeding maternal role attainment. Longitudinal cohort study. Three urban hospitals within Sydney, Australia. 449 women were invited to participate in the study, with an 81% response rate. Self-report questionnaires were used to collect the data in pregnancy (28-36 weeks) and 2 weeks and 3 months after birth. The Edinburgh Postnatal Depression Scale (EPDS) was used to measure postnatal distress, and the Maternal Role Attainment subscale (MRA) of the Maternal Breast Feeding Evaluation Scale (MBFES) was used to measure breast feeding maternal role attainment. Women with high MRA were less likely to stop breast feeding (even when they had breast feeding problems) than women with low MRA. Antenatal EPDS and anxiety scores were not related to breast feeding cessation or breast feeding problems when analysed alone. As hypothesised, the relationship between breast feeding cessation and postnatal distress (EPDS scores) varied according to MRA level. Women who were categorised as high MRA and no longer breast feeding had higher EPDS scores and were more likely to be categorised as distressed (36%) than women who had low MRA (<12%) or women who had high MRA and continued to breast feed (7%). There is a complex relationship between maternal identity, stopping breast feeding earlier than desired, and psychological distress. Women with strong beliefs about the importance of breast feeding to their maternal role may benefit from psychological assessment and support should they decide to stop breast feeding earlier.
Scheduled Relaxation Jacobi method: Improvements and applications
NASA Astrophysics Data System (ADS)
Adsuara, J. E.; Cordero-Carrión, I.; Cerdá-Durán, P.; Aloy, M. A.
2016-09-01
Elliptic partial differential equations (ePDEs) appear in a wide variety of areas of mathematics, physics and engineering. Typically, ePDEs must be solved numerically, which sets an ever growing demand for efficient and highly parallel algorithms to tackle their computational solution. The Scheduled Relaxation Jacobi (SRJ) is a promising class of methods, atypical for combining simplicity and efficiency, that has been recently introduced for solving linear Poisson-like ePDEs. The SRJ methodology relies on computing the appropriate parameters of a multilevel approach with the goal of minimizing the number of iterations needed to cut down the residuals below specified tolerances. The efficiency in the reduction of the residual increases with the number of levels employed in the algorithm. Applying the original methodology to compute the algorithm parameters with more than 5 levels notably hinders obtaining optimal SRJ schemes, as the mixed (non-linear) algebraic-differential system of equations from which they result becomes notably stiff. Here we present a new methodology for obtaining the parameters of SRJ schemes that overcomes the limitations of the original algorithm and provide parameters for SRJ schemes with up to 15 levels and resolutions of up to 215 points per dimension, allowing for acceleration factors larger than several hundreds with respect to the Jacobi method for typical resolutions and, in some high resolution cases, close to 1000. Most of the success in finding SRJ optimal schemes with more than 10 levels is based on an analytic reduction of the complexity of the previously mentioned system of equations. Furthermore, we extend the original algorithm to apply it to certain systems of non-linear ePDEs.
Mobasheri, Nasrin; Karimi, Mehrdad; Hamedi, Javad
2018-06-05
New methods to determine antimicrobial susceptibility of bacterial pathogens especially the minimum inhibitory concentration (MIC) of antibiotics have great importance in pharmaceutical industry and treatment procedures. In the present study, the MIC of several antibiotics was determined against some pathogenic bacteria using macrodilution test. In order to accelerate and increase the efficiency of culture-based method to determine antimicrobial susceptibility, the possible relationship between the changes in some physico-chemical parameters including conductivity, electrical potential difference (EPD), pH and total number of test strains was investigated during the logarithmic phase of bacterial growth in presence of antibiotics. The correlation between changes in these physico-chemical parameters and growth of bacteria was statistically evaluated using linear and non-linear regression models. Finally, the calculated MIC values in new proposed method were compared with the MIC derived from macrodilution test. The results represent significant association between the changes in EPD and pH values and growth of the tested bacteria during the exponential phase of bacterial growth. It has been assumed that the proliferation of bacteria can cause the significant changes in EPD values. The MIC values in both conventional and new method were consistent to each other. In conclusion, cost and time effective antimicrobial susceptibility test can be developed based on monitoring the changes in EPD values. The new proposed strategy also can be used in high throughput screening of biocompounds for their antimicrobial activity in a relatively shorter time (6-8 h) in comparison with the conventional methods.
Kalra, Harish; Reilly, Nicole; Austin, Marie-Paule
2018-01-30
There is limited information relating to routine depression screening and psychosocial assessment programs in private maternity settings in Australia. To describe the psychosocial profile of a sample of private maternity patients who participated in a depression screening and psychosocial risk assessment program as part of routine antenatal care, and to explore women's experience of receiving this component of pregnancy care. We conducted a retrospective medical records audit of 455 consecutive women having a routine psychosocial assessment and referral. Assessment was undertaken using the Edinburgh Postnatal Depression Scale (EPDS) and the Antenatal Risk Questionnaire (ANRQ) for psychosocial risk; 101 women completed a feedback survey about their experience of receiving routine psychosocial care. Of the 87.7% of women who completed both EPDS and ANRQ, 4.3% scored 13 or more on the EPDS. On the ANRQ, 25.3% of women endorsed one risk factor, 11.6% two risk factors and 10.5% three or more risk factors. Elevated EPDS scores were associated with major stresses in the last 12 months, high trait anxiety and significant past mental health issue/s. Acceptability of depression screening and psychosocial risk assessment was high. This study highlights the need for, and acceptability of, depression and psychosocial assessment in the private maternity sector. These findings are particularly timely given the provision of new Medicare Benefits Scheme items for obstetricians to undertake psychosocial assessment (both antenatally and postnally) in line with recommended clinical best practice. © 2018 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.
Effects of a brief psychoanalytic intervention for perinatal depression.
Nanzer, Nathalie; Sancho Rossignol, Ana; Righetti-Veltema, Marion; Knauer, Dora; Manzano, Juan; Palacio Espasa, Francisco
2012-08-01
This pilot study explores the effects of a brief individual psychoanalytic therapy on perinatal depressive symptoms. This intervention is based on the Geneva's mother-infant intervention model. A sample of 129 pregnant women was recruited in Geneva (Switzerland) and screened for depressive symptoms with two instruments: the 'Edinburgh postnatal depression scale' (EPDS) and the 'Dépistage anténatal de la dépression postnatale'. A group of 40 women presenting depressive symptoms (treatment group) participated in a four-session intervention called 'Psychotherapy centred on parenthood (PCP)'. It consists in two antenatal and two postnatal sessions and is focussed on changing problematic representations of parenthood. This treatment group was compared to a control group of 88 women without depressive symptoms and following the usual obstetrical care. The main outcome measure was EPDS at 3 and 6 months after delivery. The 'Global assessment functioning scale' was administered at the end of each therapeutic session. The 'Parent-infant relationship global assessment scale' was administered at the two postnatal sessions in order to explore if PCP was also effective in preventing the potential negative effects of depression on mother-infant relationship. Results show that in the treatment group (N = 31), EPDS scores dropped from 12.8 to 4.8; none of these women met the EPDS cut-off score of 12 at 3 and 6 months postpartum. Mother-infant relationship was well adapted for all 31 dyads at the end of the intervention. These results suggest that PCP is a promising intervention for treating perinatal depression and helping mothers engaging in parenting.
Postpartum Depression in Mothers of Infants With Cleft Lip and/or Palate.
Johns, Alexis L; Hershfield, Jennifer A; Seifu, Netsanet Mulugeta; Haynes, Karla A
2018-02-23
This study describes postpartum depression rates and risk factors for mothers with infants with cleft lip and/or palate as postpartum depression has been associated with a range of negative maternal and child outcomes. A retrospective chart review from August 2009 to May 2015 included medical diagnoses, demographics, receipt of prenatal diagnosis, and the Edinburgh Postnatal Depression Scale (EPDS). Mothers (N = 206) had infants (59.2% male; mean age in weeks 5.1 ± 6.9) with isolated cleft lip (18%), cleft palate (22.8%), or cleft lip and palate (59.2%). Mothers ranged from 16 to 45 years old (mean age 29 ± 6.2) and half had received a prenatal diagnosis. Patients mostly had public insurance (57.8%) and represented diverse ethnicities. Based on the EPDS, 11.7% of mothers met the depression cutoff of 10 or higher. The majority endorsed self-blame (68.9%), difficulty coping (59.2%), and feeling anxious (57.3%). Mothers of infants with cleft lip or cleft lip and palate who did not receive a prenatal diagnosis had higher total EPDS scores, anxiety, and incidence of feeling scared. Higher EPDS scores were predicted by not having a prenatal diagnosis and by older maternal age. Mothers of infants with a cleft had similar rates of postpartum depression as the general population; however, those who were older and who did not receive a prenatal diagnosis endorsed more symptoms. Prenatal diagnosis may contribute to positive maternal postpartum adjustment. Providers should incorporate screening for risk factors into their evaluation and treatment planning.
Closa-Monasterolo, R; Gispert-Llaurado, M; Canals, J; Luque, V; Zaragoza-Jordana, M; Koletzko, B; Grote, V; Weber, M; Gruszfeld, D; Szott, K; Verduci, E; ReDionigi, A; Hoyos, J; Brasselle, G; Escribano Subías, J
2017-07-01
Background Maternal postpartum depression (PPD) could affect children's emotional development, increasing later risk of child psychological problems. The aim of our study was to assess the association between child's emotional and behavioural problems and mother's PPD, considering maternal current mental health problems (CMP). Methods This is a secondary analysis from the EU-Childhood Obesity Project (NCT00338689). Women completed the Edinburgh Postnatal Depression Scale (EPDS) at, 2, 3 and 6 months after delivery and the General Health Questionnaire (GHQ-12) to assess CMP once the children reached the age of 8 years. EPDS scores > 10 were defined as PPD and GHQ-12 scores > 2 were defined as CMP. The psychological problems of the children at the age of eight were collected by mothers through the Child's Behaviour Checklist (CBCL). Results 473, 474 and 459 mothers filled in GHQ-12 and CBCL tests at 8 years and EPDS at 2, 3 and 6 months, respectively. Anxiety and depression was significantly increased by maternal EPDS. Children whose mothers had both PPD and CMP exhibited the highest levels of psychological problems, followed by those whose mothers who had only CMP and only PPD. PPD and CMP had a significant effect on child's total psychological problems (p = 0.033, p < 0.001, respectively). Children whose mothers had PPD did not differ from children whose mothers did not have any depression. Conclusions Maternal postpartum depression and current mental health problems, separately and synergistically, increase children's psychological problems at 8 years.
Tuohy, Alan; McVey, Cynthia
2008-06-01
There has been considerable research and clinical interest in the comorbidity of anxiety and depression in the post-partum period, and specifically in the possibility that the commonly used Edinburgh Postnatal Depression Scale (EPDS) incorporates an anxiety component. We hypothesized that the recommended version of factor analysis (Fabrigar, Wegener, MacCallum, & Strahan, 1999) would identify such covert dimensions more reliably than the commonly used principal components analysis with varimax rotation and eigenvalues greater than 1. Principal axis factor extraction with parallel analysis and oblique (direct quartimin) factor rotation was applied to the 10 EPDS items. The study used a sample of recent mothers recruited and assessed via e-mail and the Internet (N=440). In addition to the EPDS, the Hospital Anxiety and Depression Scale (HADS) and the Positive and Negative Affect Scales (PANAS) were also administered. Three factors were found, which were identified as 'non-specific depressive symptoms', 'anhedonia', and 'anxietal symptoms' subscales, respectively. These subscales were regressed on the HADS anxiety and depression and the PANAS positive and negative affectivity scales, with results substantially consistent with current structural models of the taxonomy of the emotional disorders. The data were obtained from a self-selected non-clinical sample. In addition, it is known that the use of computer-based assessment may tend to inflate self-report scores. It was concluded that there is now sufficient evidence that clinicians should not assume the EPDS to be unidimensional, but should assess all three subscales when screening for susceptibility to post-partum depression and/or post-partum anxiety.
NASA Astrophysics Data System (ADS)
Khaidir Noor, Muhammad
2018-03-01
Reserve estimation is one of important work in evaluating a mining project. It is estimation of the quality and quantity of the presence of minerals have economic value. Reserve calculation method plays an important role in determining the efficiency in commercial exploration of a deposit. This study was intended to calculate ore reserves contained in the study area especially Pit Block 3A. Nickel ore reserve was estimated by using detailed exploration data, processing by using Surpac 6.2 by Inverse Distance Weight: Squared Power estimation method. Ore estimation result obtained from 30 drilling data was 76453.5 ton of Saprolite with density of 1.5 ton/m3 and COG (Cut Off Grade) Ni ≥ 1.6 %, while overburden data was 112,570.8 tons with waste rock density of 1.2 ton/m3 . Striping Ratio (SR) was 1.47 : 1 smaller than Stripping Ratio ( SR ) were set of 1.60 : 1.
Moseley, Michael William; Allerman, Andrew A.; Crawford, Mary H.; ...
2014-08-04
Electrical current transport through leakage paths in AlGaN-based deep ultraviolet (DUV) lightemitting diodes (LEDs) and their effect on LED performance are investigated. Open-core threading dislocations, or nanopipes, are found to conduct current through nominally insulating Al0.7Ga0.3N layers and limit the performance of DUV-LEDs. A defect-sensitive phosphoric acid etch reveals these opencore threading dislocations in the form of large, micron-scale hexagonal etch pits visible with optical microscopy, while closed-core screw-, edge-, and mixed-type threading dislocations are represented by smaller and more numerous nanometer-scale pits visible by atomic-force microscopy. The electrical and optical performances of DUV-LEDs fabricated on similar Si-doped Al0.7Ga0.3N templatesmore » are found to have a strong correlation to the density of these nanopipes, despite their small fraction (<0.1% in this study) of the total density of threading dislocations.« less
Understanding Self-Catalyzed Epitaxial Growth of III-V Nanowires toward Controlled Synthesis.
Zi, Yunlong; Suslov, Sergey; Yang, Chen
2017-02-08
The self-catalyzed growth of III-V nanowires has drawn plenty of attention due to the potential of integration in current Si-based technologies. The homoparticle-assisted vapor-liquid-solid growth mechanism has been demonstrated for self-catalyzed III-V nanowire growth. However, the understandings of the preferred growth sites of these nanowires are still limited, which obstructs the controlled synthesis and the applications of self-catalyzed nanowire arrays. Here, we experimentally demonstrated that thermally created pits could serve as the preferred sites for self-catalyzed InAs nanowire growth. On that basis, we performed a pregrowth annealing strategy to promote the nanowire density by enhancing the pits formation on the substrate surface and enable the nanowire growth on the substrate that was not capable to facilitate the growth. The discovery of the preferred self-catalyzed nanowire growth sites and the pregrowth annealing strategy have shown great potentials for controlled self-catalyzed III-V nanowire array growth with preferred locations and density.
NASA Astrophysics Data System (ADS)
Boniatti, Rosiana; Bandeira, Aline L.; Crespi, Ângela E.; Aguzzoli, Cesar; Baumvol, Israel J. R.; Figueroa, Carlos A.
2013-09-01
The interaction of bio-ethanol on steel surfaces modified by plasma-assisted diffusion technologies is studied for the first time. The influence of surface microstructure and chemical composition on corrosion behaviour of AISI 4140 low-alloy steel in fuel-grade bio-ethanol was investigated. The steel surfaces were modified by plasma nitro-carburizing followed plasma oxidizing. X-ray diffraction, scanning electron microscopy, optical microscopy, X-ray dispersive spectroscopy, and glow-discharge optical emission spectroscopy were used to characterize the modified surface before and after immersion tests in bio-ethanol up to 77 days. The main corrosion mechanism is pit formation. The pit density and pit size were measured in order to quantify the corrosion resistance which was found to depend more strongly on microstructure and morphology of the oxide layer than on its thickness. The best corrosion protection was observed for samples post-oxidized at 480 °C and 90 min.
Fabrication of (Ba,K)Fe2As2 tapes by ex situ PIT process using Ag-Sn alloy single sheath
NASA Astrophysics Data System (ADS)
Togano, K.; Gao, Z.; Matsumoto, A.; Kikuchi, A.; Kumakura, H.
2017-01-01
Instead of ordinal pure Ag, Ag-based Sn binary alloys (up to 7.5 at%Sn) with higher mechanical strength are used for the sheath material of ex situ powder-in-tube (PIT)-processed (Ba,K)Fe2As2(Ba-122) tapes. We found that the use of the Ag-Sn alloy enhances the densification and texturing of the Ba-122 core, resulting in higher transport, J c. Moreover, the optimum heat treatment temperature for a high J c can be lowered by around 100 °C due to the higher packing density of the Ba-122 core prior to the final heat treatment. We also found that the smoothness of the interface between the sheath and Ba-122 core is significantly improved by using the Ag-Sn binary alloy sheaths. These results show that the Ag-Sn alloy is promising as a sheath material in PIT-processed Ba-122 superconducting wires.
Corrosion behavior of ferritic stainless steel with 15wt% chromium for the automobile exhaust system
NASA Astrophysics Data System (ADS)
Li, Hua-bing; Jiang, Zhou-hua; Feng, Hao; Zhu, Hong-chun; Sun, Bin-han; Li, Zhen
2013-09-01
The effect of chloride ion concentration, pH value, and grain size on the pitting corrosion resistance of a new ferritic stainless steel with 15wt% Cr was investigated using the anodic polarization method. The semiconducting properties of passive films with different chloride ion concentrations were performed using capacitance measurement and Mott-Schottky analysis methods. The aging precipitation and intergranular corrosion behavior were evaluated at 400-900°C. It is found that the pitting potential decreases when the grain size increases. With the increase in chloride ion concentration, the doping density and the flat-bland potential increase but the thickness of the space charge layer decreases. The pitting corrosion resistance increases rapidly with the decrease in pH value. Precipitants is identified as Nb(C,N) and NbC, rather than Cr-carbide. The intergranular corrosion is attributed to the synergistic effects of Nb(C,N) and NbC precipitates and Cr segregation adjacent to the precipitates.
NASA Astrophysics Data System (ADS)
Hekmat, F.; Sohrabi, B.; Rahmanifar, M. S.; Jalali, A.
2015-06-01
Multi-wall carbon nanotubes (MW-CNTs) have been arranged in nanochannels of anodic aluminum oxide template (AAO) by electrophoretic deposition (EPD) to make a vertically-aligned carbon nanotube (VA-CNT) based electrode. Well ordered AAO templates were prepared by a two-step anodizing process by applying a constant voltage of 45 V in oxalic acid solution. The stabilized CNTs in a water-soluble room temperature ionic liquid (1-methyl-3-octadecylimidazolium bromide), were deposited in the pores of AAO templates which were conductive by deposition of Ni nanoparticles in the bottom of pores. In order to obtain ideal results, different EPD parameters, such as concentration of MWCNTs and ionic liquid on stability of MWCNT suspensions, deposition time and voltage which are applied in EPD process and also optimal conditions for anodizing of template were investigated. The capacitive performance of prepared electrodes was analyzed by measuring the specific capacitance from cyclic voltammograms and the charge-discharge curves. A maximum value of 50 Fg-1 at the scan rate of 20 mV s-1was achieved for the specific capacitance.
Elevated risk of adverse obstetric outcomes in pregnant women with depression.
Kim, Deborah R; Sockol, Laura E; Sammel, Mary D; Kelly, Caroline; Moseley, Marian; Epperson, C Neill
2013-12-01
In this study, we evaluated the association between prenatal depression symptoms adverse birth outcomes in African-American women. We conducted a retrospective cohort study of 261 pregnant African-American women who were screened with the Edinburgh Postnatal Depression Scale (EPDS) at their initial prenatal visit. Medical records were reviewed to assess pregnancy and neonatal outcomes, specifically preeclampsia, preterm birth, intrauterine growth retardation, and low birth weight. Using multivariable logistic regression models, an EPDS score ≥10 was associated with increased risk for preeclampsia, preterm birth, and low birth weight. An EPDS score ≥10 was associated with increased risk for intrauterine growth retardation, but after controlling for behavioral risk factors, this association was no longer significant. Patients who screen positive for depression symptoms during pregnancy are at increased risk for multiple adverse birth outcomes. In a positive, patient-rated depression screening at the initial obstetrics visit, depression is associated with increased risk for multiple adverse birth outcomes. Given the retrospective study design and small sample size, these findings should be confirmed in a prospective cohort study.
Lee, Myung W.; Song, C.K.
2012-01-01
In this study, solution processes were developed for backplane using an organic thin film transistor (OTFT) as a driving device for an electrophoretic display (EPD) panel. The processes covered not only the key device of OTFTs but also interlayer and pixel electrodes. The various materials and printing processes were adopted to achieve the requirements of devices and functioning layers. The performance of OTFT of the backplane was sufficient to drive EPD sheet by producing a mobility of 0.12 cm2/v x sec and on/off current ratio of 10(5).
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 3
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 3 continues the presentation of IOA worksheets.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 2
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 2 continues the presentation of IOA worksheets.
NASA Technical Reports Server (NTRS)
Cour-Palais, B. G.; Kessler, D. J.; Zook, H. A.; Clanton, U. S.
1985-01-01
The possibility that the pitting that occurred in the STS-8 Orbiter windows was caused by dust from the El Chichon volcano eruption in March-April 1982 is considered. The pit density was more than 30/sq cm, most being 2.5-5 microns deep, and showed no evidence of impact melting. An 'alley' of higher incidence of pits in one window coincided with the line of a seam between TPS tiles. The particles causing the sandblasting were concluded to have arrived in parallel and could not be attributed to the ET, SRBs or a dust storm. The sulfuric gas-rich El Chichon plume injected sufficient material into the atmosphere so that the globe was soon encircled. Most of the resulting particulates (480-8400 tons) stayed in the Northern Hemisphere, and H2SO4 and ash concentrations were high during the STS-8 mission. The Orbiter cut through the debris layer at 19.8 km altitude at a 10 deg angle of attack, which matches the particle crater impact angle in the Orbiter windows. Since the passage was at night, larger H2SO4 droplets may have coalesced and formed larger particles on available solid nuclei, thus producing the 20-40 microns cratering observed in the windows.
NASA Astrophysics Data System (ADS)
Pujar, M. G.; Anita, T.; Shaikh, H.; Dayal, R. K.; Khatak, H. S.
2007-08-01
In the present paper, studies were conducted on AISI Type 316 stainless steel (SS) in deaerated solutions of sodium sulfate as well as sodium chloride to establish the effect of sulfate and chloride ions on the electrochemical corrosion behavior of the material. The experiments were conducted in deaerated solutions of 0.5 M sodium sulfate as well as 0.5 M sodium chloride using electrochemical noise (EN) technique at open circuit potential (OCP) to collect the correlated current and potential signals. Visual records of the current and potential, analysis of data to arrive at the statistical parameters, spectral density estimation using the maximum entropy method (MEM) showed that sulfate ions were incorporated in the passive film to strengthen the same. However, the adsorption of chloride ions resulted in pitting corrosion thereby adversely affecting noise resistance ( R N). Distinct current and potential signals were observed for metastable pitting, stable pitting and passive film build-up. Distinct changes in the values of the statistical parameters like R N and the spectral noise resistance at zero frequency ( R°SN) revealed adsorption and incorporation of sulfate and chloride ions on the passive film/solution interface.
Ma, Y J; Zhong, Z; Yang, X J; Fan, Y L; Jiang, Z M
2013-01-11
We investigated the molecular beam epitaxy growth of three-dimensional (3D) Ge quantum dot crystals (QDCs) on periodically pit-patterned Si substrates. A series of factors influencing the growth of QDCs were investigated in detail and the optimized growth conditions were found. The growth of the Si buffer layer and the first quantum dot (QD) layer play a key role in the growth of QDCs. The pit facet inclination angle decreased with increasing buffer layer thickness, and its optimized value was found to be around 21°, ensuring that all the QDs in the first layer nucleate within the pits. A large Ge deposition amount in the first QD layer favors strain build-up by QDs, size uniformity of QDs and hence periodicity of the strain distribution; a thin Si spacer layer favors strain correlation along the growth direction; both effects contribute to the vertical ordering of the QDCs. Results obtained by atomic force microscopy and cross-sectional transmission electron microscopy showed that 3D ordering was achieved in the Ge QDCs with the highest ever areal dot density of 1.2 × 10(10) cm(-2), and that the lateral and the vertical interdot spacing were ~10 and ~2.5 nm, respectively.
NASA Astrophysics Data System (ADS)
Gurioli, L.; Houghton, B.; Polacci, M.; Harris, A.
2005-12-01
During November 2004 a multidisciplinary experiment was deployed for a 10-days period at Villarrica Volcano (Chile). Activity since the 1984-85 eruption has consisted of continuous, passive degassing from a summit lava lake/vent and subordinate strombolian activity. During the experiment, a small lava lake was active within a 70-m-deep summit pit. Within the lake regular bubble bursting ejected fragments that rose and fell within the crater itself, together with splashing of lava onto the inner pit walls. Rarer, more energetic events emplaced scoria around the crater rim extending just a few 10's of meters from the pit rim. The limited dispersion of the products, confirm the low energy character of even these events. This report presents preliminary analyses of the textural features of the juvenile material ejected by the low energy strombolian events that occurred between November 8 and 17. We collected two sample suites of 100-to-300 clasts lying on fresh snow at the eastern and western sides of the crater area and within 50 m of the pit edge. Products included decimeter-sized bombs, scoria lapilli, centimeter-sized reticulites and coarse ash comprising fresh glassy shards. Bombs were rounded as well as elongated, and included spindle bombs and flattened spatter forms. Apart from the golden reticulites, all products were black and iridescent, with metallic surface lusters. We have completed density measurements on pyroclasts ranging from 2 to 7 cm in diameter. The juvenile population of the first (8 November) sample was dominated by scoria (65%) with vesicularities of 50-80%, with the remaining 35% comprising pumice/reticulite with vesicularities of 79-94%. The second (17 November) sample had a lower percentage of reticulite (less than 15% of the total sample) with vesicularities of 89-96%. The scoria in this sample had vesicularities of 41-81%. In general reticulite is characterized by rare large vesicles (up to 5 mm diameter) in a closely packed network of mostly spherical medium-to-small bubbles, with scarce phenocrysts (olivine and plagioclase) and clear microlite-free glass. In contrast the scoria fragments contained abundant phenocrysts and microphenocrysts (olivine and plagioclase) which increase in abundance with increasing density. Low and medium density scoria were typically characterized by a single large (cm-sized) rounded vesicle at their core, surrounded by abundant small vesicles. The high-density scoriae show a decrease in the abundance of small vesicles.
Modification of Einstein A Coefficient in Dissipative Gas Medium
NASA Technical Reports Server (NTRS)
Cao, Chang-Qi; Cao, Hui; Qin, Ke-Cheng
1996-01-01
Spontaneous radiation in dissipative gas medium such as plasmas is investigated by Langevin equations and the modified Weisskopf-Wigner approximation. Since the refractive index of gas medium is expected to be nearly unity, we shall first neglect the medium polarization effect. We show that absorption in plasmas may in certain case modify the Einstein A coefficient significantly and cause a pit in the A coefficient-density curves for relatively low temperature plasmas and also a pit in the A coefficient-temperature curves. In the next, the effect of medium polarization is taken into account in addition. To our surprise, its effect in certain case is quite significant. The dispersive curves show different behaviors in different region of parameters.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Teague, L.; Duff, M.; Cadieux, J.
2010-09-24
A combination of atomic force microscopy, optical microscopy, and mass spectrometry was employed to study CdZnTe crystal surface and used etchant solution following exposure of the CdZnTe crystal to the Everson etch solution. We discuss the results of these studies in relationship to the initial surface preparation methods, the performance of the crystals as radiation spectrometers, the observed etch pit densities, and the chemical mechanism of surface etching. Our results show that the surface features that are exposed to etchants result from interactions with the chemical components of the etchants as well as pre-existing mechanical polishing.
NASA Astrophysics Data System (ADS)
Morozova, L. V.; Zhegina, I. P.; Grigorenko, V. B.; Fomina, M. A.
2017-07-01
High-resolution methods of metal physics research including electron, laser and optical microscopy are used to study the kinetics of the accumulation of slip lines and bands and the corrosion damage in the plastic zone of specimens of aluminum-lithium alloys 1441 and B-1469 in rigid-cycle fatigue tests under the joint action of applied stresses and corrosive environment. The strain parameters (the density of slip bands, the sizes of plastic zones near fracture, the surface roughness in singled-out zones) and the damage parameters (the sizes of pits and the pitting area) are evaluated.
NASA Astrophysics Data System (ADS)
Farrell, Stuart Bennett
Mercury Cadmium Telluride (HgCdTe) is a material of great importance for infrared focal plane array applications. In order to produce large format detector arrays this material needs to be grown on a large area substrate, with silicon being the most mature substrate, it is the optimal choice for large format arrays. To help mitigate the effect of the lattice mismatch between the two materials, cadmium telluride (CdTe) is used as a buffer layer. The CdTe itself has nearly the same lattice mismatch (19.3%) to silicon, but due to the technological advantages it offers and compatibility with HgCdTe, it is the best buffer layer choice. The lattice mismatch between HgCdTe/CdTe and the silicon substrate leads to the formation of dislocations at densities in the mid 106 to low 107 cm-2 range in the epilayers. Such a high dislocation density greatly effects detector device performance quantities such as operability and sensitivity. Hence, the dislocation density should be brought down by at least an order of magnitude by adopting novel in situ and ex situ material processing techniques. In this work, in situ and ex situ thermal cycle annealing (TCA) methods have been used to decrease dislocation density in CdTe and HgCdTe. During the molecular beam epitaxial (MBE) growth of the CdTe buffer layer, the growth was interrupted and the layer was subjected to an annealing cycle within the growth chamber under tellurium overpressure. During the annealing cycle the temperature is raised to beyond the growth temperature (290 → 550 °C) and then allowed to cool before resuming growth again. This process was repeated several times during the growth. After growth, a portion of the material was subjected to a dislocation decoration etch in order to count the etch pit density (EPD) which has a direct correspondence with the dislocation density in the crystal. The crystalline quality was also characterized by x-ray diffraction rocking curves and photoluminescence. The in situ TCA resulted in almost a two order of magnitude reduction in the dislocation density, and factor of two reduction in the full width at half maximum of the x-ray rocking curves. Photoluminescence also suggested a decrease in the number of dislocations present in the material. This decrease is attributed to the movement of the dislocations during the annealing cycles and their subsequent interaction and annihilation. To decrease the dislocation density in HgCdTe layers grown on CdTe/Si composite substrates, ex situ TCA has been performed in a sealed quartz ampoule under a mercury overpressure in a conventional clam-shell furnace. The reduction in the dislocation density has been studied as a function of growth/annealing parameters such as the initial (as grown) dislocation density, buffer layer quality, Hg overpressure, annealing temperature, annealing duration, and the number of annealing cycles. It was found that the primary parameters that affect dislocation density reduction are the annealing temperature and the number of annealing cycles. Some secondary affects were observed by varying the duration spent at the maximum annealing temperature. Parameters such as the initial dislocation density and buffer layer quality did not play a significant role in dislocation reduction. Though no correlation between Hg overpressure and dislocation density was found, it did play a vital role in maintaining the quality of the surface. By using the ex situ TCA, a dislocation density of 1 x 106 cm-2 could be reliably and consistently achieved in HgCdTe layers that had a starting density ranging from 0.5 -- 3 x 107 cm-2. Examination of the annealing parameters revealed an exponential decay in the dislocation density as a function of increasing number of annealing cycles. In addition, a similar exponential decay was observed between the dislocation density and the annealing temperature. The decrease in the dislocation density is once again attributed to moving dislocations that interact and annihilate. This behavior was modeled using a second order reaction equation. It was found that the results of the model closely agreed with the experimental values for a wide range of annealing temperatures and number of annealing cycles.
NASA Astrophysics Data System (ADS)
Wright, Ellen E.
Due to their high specific strength (strength/density) and specific stiffness (elastic modulus/density), Al-Li alloys are attractive alloys for structural aircraft applications. To produce contoured aircraft components from Al-Li wrought products, stretch forming prior to aging is a common manufacturing technique. The effects of different amounts of tensile straining (0-9%) on the mechanical, microstructural, and corrosion properties of two third generation Al-Li alloys (2099 and 2196) were investigated. In addition to typical characterization techniques, electron backscatter diffraction (EBSD), 2D micro-digital image correlation (DIC), and scanning Kelvin probe force microscopy (SKPFM) were used to examine site-specific effects of orientation, micro-strain evolution during straining, and surface potential on corrosion, respectively. Tapping mode atomic force microscopy (AFM) was also performed to study galvanic corrosion in artificial seawater (3.5% NaCl) as it occurred in-situ. There was evidence of intergranular corrosion for 0% strain conditions, but the dominant form of corrosion was localized pitting for all specimens except Alloy 2196 strained 0%. Pitting initiated at grain boundaries and triple points. In many cases, pitting extended into particular grains and was elongated in the extrusion direction. Regions of high micro-strain preferentially corroded, and large, recrystallized grains in mostly unrecrystallized microstructures were detrimental to corrosion properties. Recommendations for improved thermomechanical processing and/or alloying to promote corrosion resistance of 2XXX series Al-Li alloys were investigated.
Wetzel, David J; Malone, Marvin A; Haasch, Richard T; Meng, Yifei; Vieker, Henning; Hahn, Nathan T; Gölzhäuser, Armin; Zuo, Jian-Min; Zavadil, Kevin R; Gewirth, Andrew A; Nuzzo, Ralph G
2015-08-26
Although rechargeable magnesium (Mg) batteries show promise for use as a next generation technology for high-density energy storage, little is known about the Mg anode solid electrolyte interphase and its implications for the performance and durability of a Mg-based battery. We explore in this report passivation effects engendered during the electrochemical cycling of a bulk Mg anode, characterizing their influences during metal deposition and dissolution in a simple, nonaqueous, Grignard electrolyte solution (ethylmagnesium bromide, EtMgBr, in tetrahydrofuran). Scanning electron microscopy images of Mg foil working electrodes after electrochemical polarization to dissolution potentials show the formation of corrosion pits. The pit densities so evidenced are markedly potential-dependent. When the Mg working electrode is cycled both potentiostatically and galvanostatically in EtMgBr these pits, formed due to passive layer breakdown, act as the foci for subsequent electrochemical activity. Detailed microscopy, diffraction, and spectroscopic data show that further passivation and corrosion results in the anisotropic stripping of the Mg {0001} plane, leaving thin oxide-comprising passivated side wall structures that demark the {0001} fiber texture of the etched Mg grains. Upon long-term cycling, oxide side walls formed due to the pronounced crystallographic anisotropy of the anodic stripping processes, leading to complex overlay anisotropic, columnar structures, exceeding 50 μm in height. The passive responses mediating the growth of these structures appear to be an intrinsic feature of the electrochemical growth and dissolution of Mg using this electrolyte.
Alhammadi, Salwa M; Hashem, Lien Abou; Abusbeih, Zainah R; Alzaabi, Fatima S; Alnuaimi, Salama N; Jalabi, Ala F; Nair, Satish C; Carrick, Frederick R; Abdulrahman, Mahera
2017-09-01
Postpartum depression (PPD) is a significant public health problem adversely affecting mothers, their newborns, and other members of the family. Although PPD is common and potentially dangerous, only a minority of the cases are identified in primary health care settings during routine care, and the majority of depressed mothers in the community lies unrecognized and therefore untreated. In this study, a total of 1500 mothers were approached randomly, 808 accepted to participate, and 504 were within the inclusion criteria (women who had a birth of a singleton full-term healthy infant, had an uncomplicated pregnancy, and were within their one week to six months postpartum). The participants completed the Edinburgh Postnatal Depression Scale. A total of 168 women had an EPDS score ≥10, yielding a crude prevalence rate of 33%. The prevalence of suicidal ideation was 14 out of 504 (3%), among which 11 (79%) had EPDS score of ≥10. We fitted multiple linear regression models to evaluate the predictors of variables measured on the EPDS scale. This model was statistically significant p<0.0001 in predicting the total EPDS score. Women's employment status, baby's birth weight, stressful life event and marital conflict were statistically significant predictors. The findings of this study are anticipated to entail the government and policy makers in the region to pay more attention to the apparently high prevalence of unrevealed PPD in the community. It is crucial to enhance screening mechanisms for early detection, providing interventions to manage symptoms, and at the same time mandating local guidelines to address the PPD pathology as a high priority for the UAE population.
Cooper, Janine A; Moriarty, Frank; Ryan, Cristín; Smith, Susan M; Bennett, Kathleen; Fahey, Tom; Wallace, Emma; Cahir, Caitriona; Williams, David; Teeling, Mary; Hughes, Carmel M
2016-05-01
The purpose of this study is to establish the prevalence of potentially inappropriate prescribing (PIP) in middle-aged adults (45-64 years) in two populations with differing socio-economic profiles, and to investigate factors associated with PIP, using the PROMPT (PRescribing Optimally in Middle-aged People's Treatments) criteria. A retrospective cross-sectional study was conducted using 2012 data from the Enhanced Prescribing Database (EPD), covering the full population in Northern Ireland and the Health Services Executive Primary Care Reimbursement Service (HSE-PCRS) database, covering the most socio-economically deprived third of the population in this age group in the Republic of Ireland. The prevalence for each PROMPT criterion and overall prevalence of PIP were calculated. Logistic regression was used to investigate the association between PIP and gender, age group and polypharmacy. This study included 441,925 patients from the EPD and 309,748 patients from the HSE-PCRS database. Polypharmacy was common in both datasets (46.7 % in the HSE-PCRS and 20.3 % in the EPD). The prevalence of PIP was 42.9 % (95%CI 42.7, 43.1) in the HSE-PCRS and 21.1 % (95%CI 21.0, 21.2) in the EPD. Age group, female gender and polypharmacy were significantly associated with PIP in both populations (p < 0.05) and polypharmacy had the strongest association. PIP is common amongst middle-aged people with the risk of PIP increasing with polypharmacy. Differences in the prevalence of polypharmacy and PIP between the two populations may relate to heterogeneity in healthcare services and different socio-economic profiles, with higher rates of multimorbidity and associated polypharmacy in more deprived groups.
Coll, Carolina de Vargas Nunes; da Silveira, Mariângela Freitas; Bassani, Diego Garcia; Netsi, Elena; Wehrmeister, Fernando César; Barros, Fernando César; Stein, Alan
2017-02-01
Antenatal depression (AD) is a major public health issue but evidence regarding its prevalence and associated factors in low and middle-income countries (LMICs) is limited. The aim of the study was to estimate the prevalence and identify risk factors for AD among Brazilian pregnant women. All women living in the urban area of the city of Pelotas, Southern Brazil, with confirmed pregnancy and estimated delivery date in the year 2015, were invited to take part. Eligible pregnant women were recruited from health services. Symptoms of antenatal depression were assessed using the Edinburgh Postnatal Depression Scale (EPDS) by face-to-face interviews. A cutoff-point of 13 or more was used to define probable AD. EPDS scores were available for 4130 women. The prevalence of AD was 16% (95%CI 14·9-17·1). After adjustment for potential confounders, the factors most strongly associated with higher EPDS scores were a previous history of depression (PR 2·81; 95%CI 2·44-3·25), high parity (PR 1·72; 95%CI 1·38-2·15 - ≥2 children vs. 1 child) and maternal education (PR 5·47; 95%CI 4·22-7·09 - 0-4 vs. ≥12 years of formal education). EPDS was administered through face-to-face interviews rather than questionnaires and some women may have felt uncomfortable reporting their symptoms leading to underreporting and consequently underestimation of the prevalence found. AD prevalence is substantially higher in Brazil than in high-income countries (HICs) but similar to other LMICs. Our study identified relevant risk factors that may be potential targets to plan interventions, particularly a history of depression. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Suicidality among pregnant women in Brazil: prevalence and risk factors.
Castro e Couto, Tiago; Brancaglion, Mayra Yara Martins; Cardoso, Mauro Nogueira; Faria, Gustavo Coutinho; Garcia, Frederico Duarte; Nicolato, Rodrigo; Aguiar, Regina Amélia Lopes P; Leite, Henrique Vitor; Corrêa, Humberto
2016-04-01
Suicide is one of the major causes of preventable death. We evaluated suicidality among pregnant women who participated in prenatal care in Brazil. A total of 255 patients were assessed using semi-structured interviews as well as the Edinburgh Postnatal Depression Scale (EPDS), Beck Depression Inventory (BDI), and Mini-International Neuropsychiatric Interview (MINI) Plus. Thereafter, Stata 12 was used to identify the significant predictors of current suicide risk (CSR) among participants using univariate and multivariate analyses (p < 0.05). According to MINI Plus module C, the lifetime suicide attempt rate was 12.55%. The overall CSR was 23.53%, distributed across risk levels of low (12.55%), moderate (1.18%), and high (9.80%). Our rates approximate those found in another Brazilian study (18.4%). Antenatal depression (AD), lifetime bipolar disorder, and any current anxiety disorder (as measured using the MINI) as well as BDI scores ≥15 and EPDS scores ≥11 were identified as positive risk factors in a univariate analysis (p < 0.001). These factors changed after a multivariate analysis was employed, and only years of education [odds ratio (OR) = 0.45; 95% confidence intervals (CIs) = 0.21-0.99], AD (OR = 3.42; 95% CIs = 1.37-8.53), and EPDS scores ≥11 (OR = 4.44; 95% CIs = 1.97-9.97) remained independent risk factors. AD and other psychiatric disorders were the primary risk factors for suicidality, although only the former remained an independent factor after a multivariate analysis. More than 10 years of education and EPDS scores ≥11 were also independent factors; the latter can be used as a screening tool for suicide risk.
Gambadauro, Pietro; Iliadis, Stavros; Bränn, Emma; Skalkidou, Alkistis
2017-08-01
To study whether conception by means of in vitro fertilization (IVF) is associated with maternal depressive symptoms during pregnancy or postpartum. Longitudinal observational study. University hospital. A total of 3,283 women with singleton pregnancies receiving antenatal care and delivering in Uppsala from 2010 to 2015. A web-based self-administered structured questionnaire including sociodemographic, clinical and pregnancy-related items, and the Edinburgh Postnatal Depression Scale (EPDS) was delivered at 17 and 32 gestational weeks and at 6 weeks and 6 months postpartum. Prevalence of significant depressive symptoms (EPDS ≥12) and EPDS scores. A total of 167 women (5%) had conceived via IVF and 3,116 (95%) had a spontaneous pregnancy. IVF mothers were more frequently ≥35 years of age (46.1% vs. 22.6%) and primiparous (71.7% vs. 49.9%) and had a higher cesarean delivery rate (22.4% vs. 14.2%). Demographic and clinical characteristics were otherwise similar between the two groups. Significant depressive symptoms were reported by 12.8%, 12.4%, 13.8%, and 11.9% of women at 17 and 32 gestational weeks and 6 weeks and 6 months postpartum, respectively. The prevalence of depressive symptoms and the EPDS scores during pregnancy and postpartum were similar between women conceiving spontaneously or through IVF. The mode of conception was not associated with significant depressive symptoms at any time point, even when adjusting for several possible confounders in multivariable logistic regression analysis. Despite the psychologic distress characterizing subfertility and its treatment, conception by means of IVF is not associated with maternal depressive symptoms during pregnancy or postpartum. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
The endpoint detection technique for deep submicrometer plasma etching
NASA Astrophysics Data System (ADS)
Wang, Wei; Du, Zhi-yun; Zeng, Yong; Lan, Zhong-went
2009-07-01
The availability of reliable optical sensor technology provides opportunities to better characterize and control plasma etching processes in real time, they could play a important role in endpoint detection, fault diagnostics and processes feedback control and so on. The optical emission spectroscopy (OES) method becomes deficient in the case of deep submicrometer gate etching. In the newly developed high density inductively coupled plasma (HD-ICP) etching system, Interferometry endpoint (IEP) is introduced to get the EPD. The IEP fringe count algorithm is investigated to predict the end point, and then its signal is used to control etching rate and to call end point with OES signal in over etching (OE) processes step. The experiment results show that IEP together with OES provide extra process control margin for advanced device with thinner gate oxide.
Kumar, Manasi; Ongeri, Linnet; Mathai, Muthoni; Mbwayo, Anne
2015-01-01
The need for a suitable tool for assessing postpartum depression in Kenya led to the process of translation of the 10 items Edinburgh Postnatal Scale into Kiswahili. The idea was to seek semantic, conceptual as well as normative equivalence in this translation. The paper discusses issues and the process of translation and provides in depth discussions around translation from the point of view of cross-cultural mental health research and practice. The English version of the EPDS screening tool was finally successfully translated into Kiswahili and the translated version is attached with this paper. PMID:25893218
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 4
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 4 continues the presentation of IOA worksheets and contains the potential critical items list.
Cerdán-Pasarán, Andrea; López-Luke, Tzarara; Esparza, Diego; Zarazúa, Isaac; De la Rosa, Elder; Fuentes-Ramírez, Rosalba; Alatorre-Ordaz, Alejandro; Sánchez-Solís, Ana; Torres-Castro, Alejandro; Zhang, Jin Z
2015-07-28
A multilayered semiconductor sensitizer structure composed of three differently sized CdSe quantum rods (QRs), labeled as Q530, Q575, Q590, were prepared and deposited on the surface of mesoporous TiO2 nanoparticles by electrophoretic deposition (EPD) for photovoltaic applications. By varying the arrangement of layers as well as the time of EPD, the photoconversion efficiency was improved from 2.0% with the single layer of CdSe QRs (TiO2/Q590/ZnS) to 2.9% for multilayers (TiO2/Q590Q575/ZnS). The optimal EPD time was shorter for the multilayered structures. The effect of CdS quantum dots (QDs) deposited by successive ionic layer adsorption and reaction (SILAR) was also investigated. The addition of CdS QDs resulted in the enhancement of efficiency to 4.1% for the configuration (TiO2/CdS/Q590Q575/ZnS), due to increased photocurrent and photovoltage. Based on detailed structural, optical, and photoelectrical studies, the increased photocurrent is attributed to broadened light absorption while the increased voltage is due to a shift in the relevant energy levels.
v Ballestrem, C-L; Strauss, M; Kächele, H
2005-05-01
Using a longitudinal screening model, 772 mothers were screened for postnatal depression after delivery in Stuttgart (Germany). This model contained the Edinburgh Postnatal Depression Scale (EPDS) and the Hamilton Depression Scale (HAMD). The first screening was 6-8 weeks after delivery with the EPDS. Mothers with high scores in the first screening had a second screening 9-12 weeks after delivery with the EPDS at least three weeks after the first. Mothers with high scores in both screenings were investigated with the Hamilton Depression Scale (HAMD). Classification was performed with the DSM-IV. After observation until the third month after delivery, 3.6% (N = 28) of the 772 mothers were diagnosed with postnatal depression. Various methods of therapy were offered to those mothers. 18% (N = 5) accepted one or more of these methods of treatment. The rest of the mothers with postnatal depression refused--mostly for attitudinal or practical reasons. 13.4% of the mothers showed high scores in the first screening but not in the second. For those mothers a longitudinal observation is currently being performed to distinguish between a depressive episode and a depression with oscillating symptoms.
Association between parental depressive symptoms and impaired bonding with the infant.
Kerstis, Birgitta; Aarts, Clara; Tillman, Carin; Persson, Hanna; Engström, Gabriella; Edlund, Birgitta; Öhrvik, John; Sylvén, Sara; Skalkidou, Alkistis
2016-02-01
Impaired bonding with the infant is associated with maternal postpartum depression but has not been investigated extensively in fathers. The primary study aim was to evaluate associations between maternal and paternal depressive symptoms and impaired bonding with their infant. A secondary aim was to determine the associations between parents' marital problems and impaired bonding with the infant. The study is part of a population-based cohort project (UPPSAT) in Uppsala, Sweden. The Edinburgh Postnatal Depression Scale (EPDS) at 6 weeks and 6 months postpartum and the Postpartum Bonding Questionnaire at 6 months postpartum were completed by 727 couples. The prevalence of impaired bonding was highest among couples in which both spouses had depressive symptoms. Impaired bonding was associated with higher EPDS scores in both mothers and fathers, as well as with experiencing a deteriorated marital relationship. The association between maternal and paternal impaired bonding and the mothers' and fathers' EPDS scores remained significant even after adjustment for relevant confounding factors. Depressive symptoms at 6 weeks postpartum are associated with impaired bonding with the infant at 6 months postpartum for both mothers and fathers. It is critical to screen for and prevent depressive symptoms in both parents during early parenthood.
Martins, Conceição S.; Leitão, Renata F. C.; Costa, Deiziane V. S.; Melo, Iracema M.; Santos, Glaylton S.; Lima, Vilma; Baldim, Victor; Wong, Deysi V. T.; Bonfim, Luana E.; Melo, Cíntia B.; Brito, Gerly A. C.
2016-01-01
S-nitrosoglutathione (GSNO) is a nitric oxide (NO) donor, which exerts antioxidant, anti-inflammatory, and microbicidal actions. Intragingival application of GSNO was already shown to decrease alveolar bone loss, inflammation and oxidative stress in an experimental periodontal disease (EPD) model. In the present study, we evaluated the potential therapeutic effect of topical applications of hydroxypropylmethylcellulose (HPMC)/GSNO solutions on EPD in Wistar rats. EPD was induced by placing a sterilized nylon (3.0) thread ligature around the cervix of the second left upper molar of the animals, which received topical applications of a HPMC solutions containing GSNO 2 or 10 mM or vehicle (HPMC solution), 1 h prior to the placement of the ligature and then twice daily until sacrifice on day 11. Treatment with HPMC/GSNO 10 mM solution significantly reduced alveolar bone loss, oxidative stress and TNF-α e IL-1β levels in the surrounding gingival tissue, and led to a decreased transcription of RANK and TNF-α genes and elevated bone alkaline phosphatase, compared to the HPMC group. In conclusion, topical application of HPMC/GSNO solution is a potential treatment to reduce inflammation and bone loss in periodontal disease. PMID:27116554
Martins, Conceição S; Leitão, Renata F C; Costa, Deiziane V S; Melo, Iracema M; Santos, Glaylton S; Lima, Vilma; Baldim, Victor; Wong, Deysi V T; Bonfim, Luana E; Melo, Cíntia B; G de Oliveira, Marcelo; Brito, Gerly A C
2016-01-01
S-nitrosoglutathione (GSNO) is a nitric oxide (NO) donor, which exerts antioxidant, anti-inflammatory, and microbicidal actions. Intragingival application of GSNO was already shown to decrease alveolar bone loss, inflammation and oxidative stress in an experimental periodontal disease (EPD) model. In the present study, we evaluated the potential therapeutic effect of topical applications of hydroxypropylmethylcellulose (HPMC)/GSNO solutions on EPD in Wistar rats. EPD was induced by placing a sterilized nylon (3.0) thread ligature around the cervix of the second left upper molar of the animals, which received topical applications of a HPMC solutions containing GSNO 2 or 10 mM or vehicle (HPMC solution), 1 h prior to the placement of the ligature and then twice daily until sacrifice on day 11. Treatment with HPMC/GSNO 10 mM solution significantly reduced alveolar bone loss, oxidative stress and TNF-α e IL-1β levels in the surrounding gingival tissue, and led to a decreased transcription of RANK and TNF-α genes and elevated bone alkaline phosphatase, compared to the HPMC group. In conclusion, topical application of HPMC/GSNO solution is a potential treatment to reduce inflammation and bone loss in periodontal disease.
Serra, B; Jiménez, S; Mena, M L; Reviejo, A J; Pingarrón, J M
2002-03-01
A comparison of the behaviour of three different rigid composite matrices for the construction of amperometric tyrosinase biosensors, which are widely used for the detection of phenolic compounds, is reported. The composite electrode matrices were, graphite-Teflon; reticulated vitreous carbon (RVC)-epoxy resin; and graphite-ethylene/propylene/diene (EPD) terpolymer. After optimization of the experimental conditions, different aspects regarding the stability of the three composite tyrosinase electrode designs were considered and compared. A better reproducibility of the amperometric responses was found with the graphite-EPD electrodes, whereas a longer useful lifetime was observed for the graphite-Teflon electrodes. The kinetic parameters of the tyrosinase reaction were calculated for eight different phenolic compounds, as well as their corresponding calibration plots. The general trend in sensitivity was graphite-EPD>graphite-Teflon>RVC-epoxy resin. A correlation between sensitivity and the catalytic efficiency of the enzyme reaction for each phenolic substrate was found. Furthermore, differences in the sensitivity order for the phenolic compounds were observed among the three biocomposite electrodes, which suggests that the nature of the electrode matrix influences the interactions in the tyrosinase catalytic cycle.
Survival, movement, and distribution of juvenile Burbot in a tributary of the Kootenai River
Beard, Zachary S.; Quist, Michael C.; Hardy, Ryan S.; Ross, Tyler J.
2017-01-01
Burbot Lota lota in the lower Kootenai River, Idaho, have been the focus of extensive conservation efforts, particularly the release of hatchery-reared juvenile Burbot into small tributaries. The Idaho Department of Fish and Game installed a fixed PIT antenna on Deep Creek, a tributary of the Kootenai River, to evaluate movement of juvenile Burbot to the Kootenai River. Since then, approximately 12,000 juvenile Burbot have been PIT-tagged and released into Deep Creek, but few Burbot have been detected at the antenna, thus raising questions about their fate in the creek. The objectives of this study were to evaluate survival, movement, and distribution of Burbot released into Deep Creek. During 2014, 3,000 age-0, 200 age-1, 16 age-2, and 16 age-4 Burbot were released at two different locations; during 2015, 3,000 age-0 Burbot were released at six different locations (i.e., 500 fish/site). Five additional stationary PIT tag antennas were installed on Deep Creek prior to stocking in 2014. Mobile PIT tag antennas were used to survey the creek in 2015 and 2016. A Barker model in Program MARK was used to estimate survival. Stationary and mobile PIT tag antennas relocated 3,372 (56%) of the Burbot released in Deep Creek during 2014 and 2015. Eighty-eight percent of PIT tags relocated during mobile surveys were relocated within 1 km of a release location. Mobile surveys of release locations in Deep Creek suggested poor dispersal from stocking locations. Survival did not vary across years or release groups. Initial 7-month survival in Deep Creek was 0.27, and survival improved to 0.63 after the first 7 months. Although survival did not differ between years or among release groups, managers may consider releasing Burbot at lower densities across multiple locations.
NASA Astrophysics Data System (ADS)
Aparin, B. F.; Mingareeva, E. V.; Sanzharova, N. I.; Sukhacheva, E. Yu.
2017-12-01
Data on the concentrations of natural (226Ra, 232Th and 40K) and artificial (137Cs) radionuclides and on the physicochemical properties of chernozems sampled in different years are presented. In 1952, upon the creation of the Penza-Kamensk state shelterbelt, three deep (up to 3 m) soil pits were examined within the former arable field under two-year-old plantations of ash and maple along the transect crossing the territory of the Beloprudskaya Experimental Station of the USSR Academy of Sciences in Volgograd oblast. The samples from these pits were included into the collection of dated soil samples of the Dokuchaev Central Soil Science Museum. Five pits were examined along the same transect in 2009: three pits under shelterbelts (analogues of the pits studied in 1952) and two pits on arable fields between the shelterbelts. In the past 57 years, certain changes took place in the soil structure, bulk density, and the content and composition of humus. The salt profile of soils changed significantly under the forests. The comparison of distribution patterns of natural soil radionuclides in 1952 and 2009 demonstrated their higher contents at the depth of 10-20 cm in 2009 (except for the western shelterbelt). Background concentrations of natural radionuclides in parent materials and relationships between their distributions and the salt profiles of soils have been determined; they are most clearly observed is the soils under shelterbelts. Insignificant contamination with 137Cs (up to 34 Bq/kg) has been found in the samples of 2009 from the upper (0-20 cm) horizon. The activity of 137Cs regularly decreases from the east to the west; the highest concentrations of this radionuclide are found in the topmost 10 cm. This allows us to suppose that 137Cs was brought with aerial dust by eastern winds, and the shelterbelts served as barriers to the wind flow.
Measurement of Direct Current Voltage Causing Electrical Pitting
NASA Astrophysics Data System (ADS)
Noguchi, Shoji; Kakinuma, Shin-Nosuke; Kanada, Tohru
It is widely known that electrical pitting occurs when an electrical current is passed through a ball or roller bearing. The authors have investigated critical electrical current density causing electrical pitting and have shown that it occurs in a ball bearing even at an extremely low current. In this paper we present the results of an experiment in which a small ball bearing was supplied with a direct current (DC) voltage to determine the voltage required to induce a current. A film of grease acts as the insulator on an antifriction bearing used, and the thickness of this film is an important consideration and the current must pass through this film. Four types of grease were used on the bearing, which was rotated at various speed during 500 hours. A potential of 1.3V to 1.5V was necessary to induce the flow of current. The results indicate that the voltage supplied by typical dry cell batteries is sufficient to drive a currents through a small bearing, and that the experimental conditions had little effect on the magnitude of the flowing current.
The study of aluminium anodes for high power density Al/air batteries with brine electrolytes
NASA Astrophysics Data System (ADS)
Nestoridi, Maria; Pletcher, Derek; Wood, Robert J. K.; Wang, Shuncai; Jones, Richard L.; Stokes, Keith R.; Wilcock, Ian
Aluminium alloys containing small additions of both tin (∼0.1 wt%) and gallium (∼0.05 wt%) are shown to dissolve anodically at high rates in sodium chloride media at room temperatures; current densities >0.2 A cm -2 can be obtained at potentials close to the open circuit potential, ∼-1500 mV versus SCE. The tin exists in the alloys as a second phase, typically as ∼1 μm inclusions (precipitates) distributed throughout the aluminium structure, and anodic dissolution occurs to form pits around the tin inclusions. Although the distribution of the gallium in the alloy could not be established, it is also shown to be critical in the formation of these pits as well as maintaining their activity. The stability of the alloys to open circuit corrosion and the overpotential for high rate dissolution, both critical to battery performance, are shown to depend on factors in addition to elemental composition; both heat treatment and mechanical working influence the performance of the alloy. The correlation between alloy performance and their microstructure has been investigated.
Investigation of transient dynamics of capillary assisted particle assembly yield
NASA Astrophysics Data System (ADS)
Virganavičius, D.; Juodėnas, M.; Tamulevičius, T.; Schift, H.; Tamulevičius, S.
2017-06-01
In this paper, the transient behavior of the particle assembly yield dynamics when switching from low yield to high yield deposition at different velocity and thermal regimes is investigated. Capillary force assisted particle assembly (CAPA) using colloidal suspension of green fluorescent 270 nm diameter polystyrene beads was performed on patterned poly (dimethyl siloxane) substrates using a custom-built deposition setup. Two types of patterns with different trapping site densities were used to assess CAPA process dynamics and the influence of pattern density and geometry on the deposition yield transitions. Closely packed 300 nm diameter circular pits ordered in hexagonal arrangement with 300 nm pitch, and 2 × 2 mm2 square pits with 2 μm spacing were used. 2-D regular structures of the deposited particles were investigated by means of optical fluorescence and scanning electron microscopy. The fluorescence micrographs were analyzed using a custom algorithm enabling to identify particles and calculate efficiency of the deposition performed at different regimes. Relationship between the spatial distribution of particles in transition zone and ambient conditions was evaluated and quantified by approximation of the yield profile with a logistic function.
Sopori, Bhushan L.
1995-01-01
Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities.
Sopori, B.L.
1995-04-11
Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. 20 figures.
Jirayupat, Chaiyanut; Wongwiriyapan, Winadda; Kasamechonchung, Panita; Wutikhun, Tuksadon; Tantisantisom, Kittipong; Rayanasukha, Yossawat; Jiemsakul, Thanakorn; Tansarawiput, Chookiat; Liangruksa, Monrudee; Khanchaitit, Paisan; Horprathum, Mati; Porntheeraphat, Supanit; Klamchuen, Annop
2018-02-21
Here, we demonstrate a novel device structure design to enhance the electrical conversion output of a triboelectric device through the piezoelectric effect called as the piezo-induced triboelectric (PIT) device. By utilizing the piezopotential of ZnO nanowires embedded into the polydimethylsiloxane (PDMS) layer attached on the top electrode of the conventional triboelectric device (Au/PDMS-Al), the PIT device exhibits an output power density of 50 μW/cm 2 , which is larger than that of the conventional triboelectric device by up to 100 folds under the external applied force of 8.5 N. We found that the effect of the external piezopotential on the top Au electrode of the triboelectric device not only enhances the electron transfer from the Al electrode to PDMS but also boosts the internal built-in potential of the triboelectric device through an external electric field of the piezoelectric layer. Furthermore, 100 light-emitting diodes (LEDs) could be lighted up via the PIT device, whereas the conventional device could illuminate less than 20 LED bulbs. Thus, our results highlight that the enhancement of the triboelectric output can be achieved by using a PIT device structure, which enables us to develop hybrid nanogenerators for various self-power electronics such as wearable and mobile devices.
NASA Technical Reports Server (NTRS)
Faur, Maria; Faur, Mircea; Weinberg, Irving; Goradia, Manju; Vargas, Carlos
1991-01-01
An extensive experimental study was conducted using various electrolytes in an effort to find an appropriate electrolyte for anodic dissolution of InP. From the analysis of electrochemical characteristics in the dark and under different illumination levels, x ray photoelectron spectroscopy and SEM/Nomarski inspection of the surfaces, it was determined that the anodic dissolution of InP front surface layers by FAP electrolyte is a very good choice for rendering smooth surfaces, free of oxides and contaminants and with good electrical characteristics. The FAP electrolyte, based on HF, CH3COOH, and H2O2 appears to be inherently superior to previously reported electrolytes for performing accurate EC-V profiling of InP at current densities of up to 0.3 mA/sq cm. It can also be used for accurate electrochemical revealing of either precipitates or dislocation density with application to EPD mapping as a function of depth, and for defect revealing of multilayer InP structures at any depth and/or at the interfaces.
Seasonal variations of snow chemistry and mineral dust in the snow pit at GV7, Antarctica
NASA Astrophysics Data System (ADS)
Kang, Jung-Ho; Hwang, Heejin; Han, Yongchoul; Hong, Sang Bum; Lee, Khanghyun; Do Hur, Soon; Frezzotti, Massimo; Narcisi, Biancamaria
2015-04-01
We conducted the scientific ice coring project led by PNRA and KOPRI during the 2013/2014 Italian-Korean Antarctic Expedition in the framework of International Partnerships in Ice Core Science (IPICS) to understand the climatic variability in the last 2000 years. In the part of project, we collected a 3.0 m-depth snow pit at the site of GV7 (S 70° 41'17.1", E 158° 51'48.9", 1950 m a.s.l.), Antarctica. Here, we present the results obtained from the analysis of the water isotope compositions, the major ion concentrations, and the mineral dust concentrations from the snow pit. Snow densities and temperatures also measured in the field. At KOPRI, the samples were melted, then the stable water isotopes, major ions, and particle size distribution were analyzed with the cavity ring-down spectrometers (L1102-i, Piccaro), ion chromatography (ICS-2100, Thermo), and coulter counter (Multisizer 3, Beckman Coulter), respectively. The δ18O varies between -38.3 and -24.1o with a mean value of -31.0o. The δD ranges between -331 and -186o with a mean value of -243o. Among the ion concentrations (Na+, Ca2+, Mg2+, Cl-, SO42-, CH3SO3-(MSA)) from the snow pit, MSA concentrations show a clear seasonal variation. The mineral dust in the pit characterized with the differences of the concentration and the particle size distribution by the seasonality. These data allow us to assume about 4.5 years of snow deposition covered from 2009 to 2013 by these oscillations of the isotopes and geochemical characteristics.
On the corrosion behavior of zircaloy-4 in spent fuel pools under accidental conditions
NASA Astrophysics Data System (ADS)
Lavigne, O.; Shoji, T.; Sakaguchi, K.
2012-07-01
After zircaloy cladding tubes have been subjected to irradiation in the reactor core, they are stored temporarily in spent fuel pools. In case of an accident, the integrity of the pool may be affected and the composition of the coolant may change drastically. This was the case in Fukushima Daiichi in March 2011. Successive incidents have led to an increase in the pH of the coolant and to chloride contamination. Moreover, water radiolysis may occur owing to the remnant radioactivity of the spent fuel. In this study, we propose to evaluate the corrosion behavior of oxidized Zr-4 (in autoclave at 288 °C for 32 days) in function of the pH and the presence of chloride and radical forms. The generation of radicals is achieved by the sonolysis of the solution. It appears that the increase in pH and the presence of radicals lead to an increase in current densities. However, the current densities remain quite low (depending on the conditions, between 1 and 10 μA cm-2). The critical parameter is the presence of chloride ions. The chloride ions widely decrease the passive range of the oxidized samples (the pitting potential is measured around +0.6 V (vs. SCE)). Moreover, if the oxide layer is scratched or damaged (which is likely under accidental conditions), the pitting potential of the oxidized sample reaches the pitting potential of the non-oxidized sample (around +0.16 V (vs. SCE)), leaving a shorter stable passive range for the Zr-4 cladding tubes.
Thermal shock induced oxidation of beryllium
NASA Astrophysics Data System (ADS)
Spilker, B.; Linke, J.; Pintsuk, G.; Wirtz, M.
2017-12-01
Beryllium has been chosen as a plasma facing material for the first wall of the experimental fusion reactor ITER, mainly because of its low atomic number and oxygen getter capabilities, which are favorable for a high plasma performance. While the steady state operational temperature of 250 °C has no deteriorating effect on the beryllium surface, transient plasma events can deposit power densities of up to 1 GW m-2 on the beryllium armor tiles. Previous research has shown that the oxidation of beryllium can occur under these thermal shock events. In the present study, S-65 grade beryllium specimens were exposed to 100 thermal shocks with an absorbed power density of 0.6 GW m-2 and a pulse duration of 1 ms, leading to a peak surface temperature of ˜800 °C. The induced surface morphology changes were compared to a steady state heated specimen at the same surface temperature with a holding time of 150 s. As a result, a pitting structure with an average pit diameter of ˜0.45 μm was observed on the thermal shock loaded surface, which was caused by beryllium oxide grain nucleation and subsequent erosion of the weakly bound beryllium oxide particles. In contrast, the steady state heated surface exhibited a more homogeneous beryllium oxide layer featuring small pits with diameters of tens of nm and showed the beryllium oxide grain nucleation in a beginning stage. The experiment demonstrated that thermal shock loading conditions can significantly accelerate the beryllium oxide grain nucleation. The resulting surface morphology change can potentially alter the fusion application relevant erosion, absorption, and retention characteristics of beryllium.
Independent Orbiter Assessment (IOA): Assessment of the reaction control system, volume 5
NASA Technical Reports Server (NTRS)
Prust, Chet D.; Hartman, Dan W.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the aft and forward Reaction Control System (RCS) hardware and Electrical Power Distribution and Control (EPD and C), generating draft failure modes and potential critical items. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter RCS hardware and EPD and C systems. Volume 5 contains detailed analysis and superseded analysis worksheets and the NASA FMEA to IOA worksheet cross reference and recommendations.
Developing a Web-Based Mechanism for Assessing Teacher Science Content Knowledge
NASA Astrophysics Data System (ADS)
Byers, Al; Koba, Susan; Sherman, Greg; Scheppke, Joan; Bolus, Roger
2011-04-01
The National Science Teachers Association (NSTA) recently launched a comprehensive electronic professional development (e-PD) online portal, the NSTA Learning Center. This support site for educators currently includes over 6,000 e-PD resources and opportunities available on-demand, as well as various tools designed to help educators maximize the effectiveness of using NSTA resources. One tool, the PD Indexer, helps teachers identify their own areas of content strengths and weaknesses by selecting content-specific assessments. Individual NSTA resources are recommended based on assessment outcomes. This paper presents a detailed description of the procedures employed by NSTA to develop valid and reliable PD Indexer content-specific multiple-choice assessment items.
NASA Astrophysics Data System (ADS)
Ramana, E. Venkata; Ferreira, N. M.; Mahajan, A.; Ferro, Marta C.; Figueiras, F.; Graça, M. P. F.; Valente, M. A.
2018-02-01
In this work, we have fabricated lead-free piezoelectric Ba0.85Ca0.15Ti0.9Zr0.1O3 thick films by the electrophoretic deposition (EPD) followed by a continuous-wave CO2 laser annealing and demonstrated the effect of laser energy on the quality of the final product. Thick films annealed under optimized conditions, 50 W/15 min, show a controlled microstructure/density compared to those derived from higher laser power/annealing time/conventional sintering. The increase in laser power above this limit affects the grain growth kinetics and results in the compositional heterogeneities. From the results of Raman spectra, it was found that the film annealed under optimized conditions has a high degree of crystallinity and tetragonality, while the increase in laser fluence results in the growth of A1g mode. The controlled composition and microstructure, thus has resulted in the improved ferroelectricity with a remanent polarization 12 μC/cm2, on par with the bulk or larger than the films grown by the chemical solution deposition techniques. From the piezoresponse studies, we found that the film annealed at 75 W/5 min has weak ferroelectric nature with no switchable ferroelectric domains compared to those under optimized conditions. Subtle differences in phase transition temperatures and drop in ferroelectric polarization, for films annealed conventionally or at higher laser fluence, are related to porosity or site defects as well as compositional heterogeneities. Our study demonstrates that the combination of EPD and laser annealing is an effective way to achieve high quality piezoelectric thick films with a controlled composition, useful for energy harvesting applications.
Sowers, Daniel; Liu, Yingzi; Mostafaei, Farshad; Blake, Scott; Nie, Linda H
2015-12-01
A neutron irradiation cavity for in vivo neutron activation analysis (IVNAA) to detect manganese, aluminum, and other potentially toxic elements in human hand bone has been designed and its dosimetric specifications measured. The neutron source is a customized deuterium-deuterium neutron generator that produces neutrons at 2.45 MeV by the fusion reaction 2H(d, n)3He at a calculated flux of 7 × 10(8) ± 30% s(-1). A moderator/reflector/shielding [5 cm high density polyethylene (HDPE), 5.3 cm graphite and 5.7 cm borated (HDPE)] assembly has been designed and built to maximize the thermal neutron flux inside the hand irradiation cavity and to reduce the extremity dose and effective dose to the human subject. Lead sheets are used to attenuate bremsstrahlung x rays and activation gammas. A Monte Carlo simulation (MCNP6) was used to model the system and calculate extremity dose. The extremity dose was measured with neutron and photon sensitive film badges and Fuji electronic pocket dosimeters (EPD). The neutron ambient dose outside the shielding was measured by Fuji NSN3, and the photon dose was measured by a Bicron MicroREM scintillator. Neutron extremity dose was calculated to be 32.3 mSv using MCNP6 simulations given a 10-min IVNAA measurement of manganese. Measurements by EPD and film badge indicate hand dose to be 31.7 ± 0.8 mSv for neutrons and 4.2 ± 0.2 mSv for photons for 10 min; whole body effective dose was calculated conservatively to be 0.052 mSv. Experimental values closely match values obtained from MCNP6 simulations. These are acceptable doses to apply the technology for a manganese toxicity study in a human population.
The search for active Europa plumes in Galileo plasma particle detector data: the E12 flyby
NASA Astrophysics Data System (ADS)
Huybrighs, H.; Roussos, E.; Krupp, N.; Fraenz, M.; Futaana, Y.; Barabash, S. V.; Glassmeier, K. H.
2017-12-01
Hubble Space Telescope observations of Europa's auroral emissions and transits in front of Jupiter suggest that recurring water vapour plumes originating from Europa's surface might exist. If conclusively proven, the discovery of these plumes would be significant, because Europa's potentially habitable ocean could be studied remotely by taking in-situ samples of these plumes from a flyby mission. The first opportunity to collect in-situ evidence of the plumes will not arise before the early 2030's when ESA's JUICE mission or NASA's Europa Clipper are set to arrive. However, it may be possible that NASA's Galileo mission has already encountered the plumes when it was active in the Jupiter system from 1995 to 2003. It has been suggested that the high plasma densities and anomalous magnetic fields measured during one of the Galileo flybys of Europa (flyby E12) could be connected to plume activity. In the context of the search for Europa plume signatures in Galileo particle data we present an overview of the in-situ plasma particle data obtained by the Galileo spacecraft during the E12 flyby. Focus is in particular on the data obtained with the plasma particle instruments PLS (low energy ions and electrons) and EPD (high energy ions and electrons). We search for signs of an extended exosphere/ionosphere that could be consistent with ongoing plume activity. The PLS data obtained during the E12 flyby show an extended interaction region between Europa and the plasma from Jupiter's magnetosphere, hinting at the existence of an extended ionosphere and exosphere. Furthermore we show how the EPD data are analyzed and modelled in order to evaluate whether a series of energetic ion depletions can be attributed to losses on the moon's surface or its neutral exosphere.
Blodgett Forest Warming Experiment 1
Pries, Caitlin Hicks (ORCID:0000000308132211); Castanha, Cristina; Porras, Rachel; Torn, Margaret
2017-03-24
Carbon stocks and density fractions from soil pits used to characterize soils of the Blodgett warming experiment as well as gas well CO2, 13C, and 14C data from experimental plots. The experiment consisted of 3 control and heated plot pairs. The heated plots are warmed +4°C above the control from 10 to 100 cm.
2012-08-07
sealed quartz ampoule under a mercury overpressure in a conventional clam-shell furnace . The reduction in the dislocation density has been studied as...46 2.6.4 Etch Pit Characterization . . . . . . . . . . . . . . . . . . . . . . . . 46 5 3 Furnace Setup and Calibration...Setup . . . . . . . . . . . . . . . . . . . . . . . 54 3.1.2 Furnace Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 4 In Situ
Snowpack ground truth: Radar test site, Steamboat Springs, Colorado, 8-16 April 1976
NASA Technical Reports Server (NTRS)
Howell, S.; Jones, E. B.; Leaf, C. F.
1976-01-01
Ground-truth data taken at Steamboat Springs, Colorado is presented. Data taken during the period April 8, 1976 - April 16, 1976 included the following: (1) snow depths and densities at selected locations (using a Mount Rose snow tube); (2) snow pits for temperature, density, and liquid water determinations using the freezing calorimetry technique and vertical layer classification; (3) snow walls were also constructed of various cross sections and documented with respect to sizes and snow characteristics; (4) soil moisture at selected locations; and (5) appropriate air temperature and weather data.
Tamrakar, Sandeep; An, Qi; Thostenson, Erik T; Rider, Andrew N; Haque, Bazle Z Gama; Gillespie, John W
2016-01-20
The electrophoretic deposition (EPD) method was used to deposit polyethylenimine (PEI) functionalized multiwall carbon nanotube (CNT) films onto the surface of individual S-2 glass fibers. By varying the processing parameters of EPD following Hamaker's equation, the thickness of the CNT film was controlled over a wide range from 200 nm to 2 μm. The films exhibited low electrical resistance, providing evidence of coating uniformity and consolidation. The effect of the CNT coating on fiber matrix interfacial properties was investigated through microdroplet experiments. Changes in interfacial properties due to application of CNT coatings onto the fiber surface with and without a CNT-modified matrix were studied. A glass fiber with a 2 μm thick CNT coating and the unmodified epoxy matrix showed the highest increase (58%) in interfacial shear strength (IFSS) compared to the baseline. The increase in the IFSS was proportional to CNT film thickness. Failure analysis of the microdroplet specimens indicated higher IFSS was related to fracture morphologies with higher levels of surface roughness. EPD enables the thickness of the CNT coating to be adjusted, facilitating control of fiber/matrix interfacial resistivity. The electrical sensitivity provides the opportunity to fabricate a new class of sizing with tailored interfacial properties and the ability to detect damage initiation.
NASA Astrophysics Data System (ADS)
Jamilpanah, L.; Azadian, S.; Shoa e Gharehbagh, J.; Haghniaz Jahromi, S.; Sheykhifard, Z.; Hosseinizadeh, S.; Erfanifam, S.; Hajiali, M. R.; Tehranchi, M. M.; Mohseni, S. M.
2018-07-01
Graphene oxide (GO) layers have shown to be fascinating elements for application in high performance sensors. They can be applied in multi-disciplinary designs based on surface selective sensing mechanisms. One immediate application of such surface sensitive elements is implementing of GO layer in magnetoimpedance (MI) sensors to improve their multi-functionality. In this paper, deposition of GO on the surface of Co-based amorphous ribbons (Co68.15Fe4.35Si12.5B15) is performed using electrophoretic deposition (EPD) method to evaluate the MI response. MI ratio increased from 271% (bare ribbon) up to 281% and 301% EPD GO deposited within 4 and 8 min, respectively. Similar experiment for the ribbon drop coated with GO was carried out while no enhancement in MI response was seen. Vertical growth of GO on the surface of the ribbon in EPD and drop coated layers observed by topographical measurements. We explained the difference between the MI responses based on layers verticality and surface coverage. UV-Visible absorption and Raman spectroscopy were used to study the nature of GO. Gaining a high surface area of GO along with their biocompatible and anticorrosive properties atop the MI sensors can open pathways towards increasing applications of surface selective and high sensitive MI sensors.
Thin and Flexible Carbon Nanotube-Based Pressure Sensors with Ultra-wide Sensing Range.
Doshi, Sagar M; Thostenson, Erik T
2018-06-26
A scalable electrophoretic deposition (EPD) approach is used to create novel thin, flexible and lightweight carbon nanotube-based textile pressure sensors. The pressure sensors can be produced using an extensive variety of natural and synthetic fibers. These piezoresistive sensors are sensitive to pressures ranging from the tactile range (< 10 kPa), in the body weight range (~ 500 kPa), and very high pressures (~40 MPa). The EPD technique enables the creation of a uniform carbon nanotube-based nanocomposite coating, in the range of 250-750 nm thick, of polyethyleneimine (PEI) functionalized carbon nanotubes on non-conductive fibers. In this work, non-woven aramid fibers are coated by EPD onto a backing electrode followed by film formation onto the fibers creating a conductive network. The electrically conductive nanocomposite coating is firmly bonded to the fiber surface and shows piezoresistive electrical/mechanical coupling. The pressure sensor displays a large in-plane change in electrical conductivity with applied out-of-plane pressure. In-plane conductivity change results from fiber/fiber contact as well as the formation of a sponge-like piezoresistive nanocomposite "interphase" between the fibers. The resilience of the nanocomposite interphase enables sensing of high pressures without permanent changes to the sensor response, showing high repeatability.
NASA Astrophysics Data System (ADS)
Veysi, Mehdi; Othman, Mohamed A. K.; Figotin, Alexander; Capolino, Filippo
2018-05-01
We propose a class of lasers based on a fourth-order exceptional point of degeneracy (EPD) referred to as the degenerate band edge (DBE). EPDs have been found in parity-time-symmetric photonic structures that require loss and/or gain; here we show that the DBE is a different kind of EPD since it occurs in periodic structures that are lossless and gainless. Because of this property, a small level of gain is sufficient to induce single-frequency lasing based on a synchronous operation of four degenerate Floquet-Bloch eigenwaves. This lasing scheme constitutes a light-matter interaction mechanism that leads also to a unique scaling law of the laser threshold with the inverse of the fifth power of the laser-cavity length. The DBE laser has the lowest lasing threshold in comparison to a regular band edge laser and to a conventional laser in cavities with the same loaded quality (Q ) factor and length. In particular, even without mirror reflectors the DBE laser exhibits a lasing threshold which is an order of magnitude lower than that of a uniform cavity laser of the same length and with very high mirror reflectivity. Importantly, this novel DBE lasing regime enforces mode selectivity and coherent single-frequency operation even for pumping rates well beyond the lasing threshold, in contrast to the multifrequency nature of conventional uniform cavity lasers.
Dubber, S; Reck, C; Müller, M; Gawlik, S
2015-04-01
Adverse effects of perinatal depression on the mother-child interaction are well documented; however, the influence of maternal-fetal bonding during pregnancy on postpartum bonding has not been clearly identified. The subject of this study was to investigate prospectively the influence of maternal-fetal bonding and perinatal symptoms of anxiety and depression on postpartum mother-infant bonding. Data from 80 women were analyzed for associations of symptoms of depression and anxiety as well as maternal bonding during pregnancy to maternal bonding in the postpartum period using the Edinburgh Postnatal Depression Scale (EPDS), the State-Trait Anxiety Inventory (STAI), the Pregnancy Related Anxiety Questionnaire (PRAQ-R), the Maternal-Fetal Attachment Scale (MFAS) and the Postpartum Bonding Questionnaire (PBQ-16). Maternal education, MFAS, PRAQ-R, EPDS and STAI-T significantly correlated with the PBQ-16. In the final regression model, MFAS and EPDS postpartum remained significant predictors of postpartum bonding and explained 20.8 % of the variance. The results support the hypothesized negative relationship between maternal-fetal bonding and postpartum maternal bonding impairment as well as the role of postpartum depressive symptoms. Early identification of bonding impairment during pregnancy and postpartum depression in mothers plays an important role for the prevention of potential bonding impairment in the early postpartum period.
Botelho, Marco Antonio; Rao, Vietla Satyanarayana; Montenegro, Danusa; Bandeira, Mary Anne Menezes; Fonseca, Said Gonçalves Cruz; Nogueira, Nadia Accioly Pinto; Ribeiro, Ronaldo Albuquerque; Brito, Gerly Anne Castro
2008-04-01
Carvacrol and dimeric chalcones are the respective bioactive components of Lippia sidoides and Myracrodruon urundeuva, popular medicinal plants of Northeastern Brazil with proven antimicrobial and antiinflammatory properties. Periodontal disease is associated with inflammation and microbiological proliferation, thus the study aimed to investigate the effect of a topical gel based on carvacrol and chalcones in the experimental periodontal disease (EPD) in rats. Animals were treated with carvacrol and/or chalcones gel, immediately after EPD induction, three times a day for 11 days. Appropriate controls were included in the study. Animals were weighed daily. They were killed on day 11, the mandibles dissected and alveolar bone loss was measured. The periodontium were examined at histopathology and the neutrophil influx into the gingiva was assayed using myeloperoxidase activity. The bacterial flora were assessed through culture of the gingival tissue. Alveolar bone loss was significantly (p < 0.05) inhibited by combined carvacrol and chalcones gel, compared with the vehicle and non-treated groups. The treatment with the combined gel reduced tissue lesion at histopathology, decreased myeloperoxidase activity in gingival tissue and inhibited the growth of oral microorganisms as well as the weight loss. Carvacrol and chalcones combination gel has a beneficial effect upon EPD in this model. (c) 2008 John Wiley & Sons, Ltd.
Ryu, Jeongjae; No, Kwangsoo; Kim, Yeontae; Park, Eugene; Hong, Seungbum
2016-01-01
In this study, we investigated the deposition kinetics of polyvinylidene fluoride copolymerized with trifluoroethylene (P(VDF-TrFE)) particles on stainless steel substrates during the electrophoretic deposition (EPD) process. The effect of applied voltage and deposition time on the structure and ferroelectric property of the P(VDF-TrFE) films was studied in detail. A method of repeated EPD and heat treatment above melting point were employed to fabricate crack-free P(VDF-TrFE) thick films. This method enabled us to fabricate P(VDF-TrFE) films with variable thicknesses. The morphology of the obtained films was investigated by scanning electron microscopy (SEM), and the formation of β-phase was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. P(VDF-TrFE) films prepared with various thicknesses showed remnant polarization (Pr) of around 4 μC/cm2. To demonstrate the applicability of our processing recipe to complex structures, we fabricated a spring-type energy harvester by depositing P(VDF-TrFE) films on stainless steel springs using EPD process. Our preliminary results show that an electrophoretic deposition can be applied to produce high-quality P(VDF-TrFE) films on planar as well as three-dimensional (3-D) substrates. PMID:27805008
Ohoka, Harue; Koide, Takayoshi; Goto, Setsuko; Murase, Satomi; Kanai, Atsuko; Masuda, Tomoko; Aleksic, Branko; Ishikawa, Naoko; Furumura, Kaori; Ozaki, Norio
2014-08-01
Postnatal depression has demonstrated long-term consequences on child cognitive and emotional development; however, the link between maternal and child pathology has not been clearly identified. We conducted a prospective study using self-rating questionnaires to clarify the association between bonding disorder and maternal mood during pregnancy and after childbirth. A total of 389 women participated in this study and completed questionnaires. Participants were asked to complete the Edinburgh Postnatal Depression Scale (EPDS) and the Mother-to-Infant Bonding Scale four times during pregnancy and the postpartum period. We found statistically significant weak to moderate correlations (r = 0.14-0.39) between the EPDS and Mother-to-Infant Bonding Scale scores at each testing period. Women who experienced low mood tended to have stronger bonding disorder. Furthermore, the effectiveness of attachment between the mother and child was closely related to the mood of the mother as measured by the EPDS. We observed different patterns of bonding and maternal mood. Distinct subtypes regarding maternal mood and formation of mother-to-infant attachment suggests that analysis of bonding disorder should be performed considering the course of maternal depressive symptoms. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.
Quality of life and depression following childbirth: impact of social support.
Webster, Joan; Nicholas, Catherine; Velacott, Catherine; Cridland, Noelle; Fawcett, Lisa
2011-10-01
to evaluate the impact of social support on postnatal depression and health-related quality of life. prospective cohort study. Data were collected at baseline and at six weeks post discharge using a postal survey. between August and December 2008, 320 women from a large tertiary hospital were recruited following the birth of their infant. Edinburgh Postnatal Depression Scale (EPDS), Maternity Social Support Scale and World Health Organization Quality of Life assessment questionnaire. of the 320 women recruited, 222 (69.4%) returned their six-week questionnaire. Women with low social support had significantly higher scores on the EPDS than women who reported adequate support (p = 0.007). There was also a significant effect of social support on health-related quality of life. Women with low family or partner support scored lower in all domains, with the greatest mean difference in the social health domain (p = 0.000). Of those scoring >10 on the EPDS, 75.5% had sought professional help. women with low social support are more likely to report postnatal depression and lower quality of life than well-supported women. Careful assessment of a woman's level of support following the birth, particularly from her partner and family, may provide useful information for possible interventions. Copyright © 2010 Elsevier Ltd. All rights reserved.
Ryu, Jeongjae; No, Kwangsoo; Kim, Yeontae; ...
2016-11-02
In this paper, we investigated the deposition kinetics of polyvinylidene fluoride copolymerized with trifluoroethylene (P(VDF-TrFE)) particles on stainless steel substrates during the electrophoretic deposition (EPD) process. The effect of applied voltage and deposition time on the structure and ferroelectric property of the P(VDF-TrFE) films was studied in detail. A method of repeated EPD and heat treatment above melting point were employed to fabricate crack-free P(VDF-TrFE) thick films. This method enabled us to fabricate P(VDF-TrFE) films with variable thicknesses. The morphology of the obtained films was investigated by scanning electron microscopy (SEM), and the formation of β-phase was confirmed by X-raymore » diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. P(VDF-TrFE) films prepared with various thicknesses showed remnant polarization (P r) of around 4 μC/cm 2. To demonstrate the applicability of our processing recipe to complex structures, we fabricated a spring-type energy harvester by depositing P(VDF-TrFE) films on stainless steel springs using EPD process. Our preliminary results show that an electrophoretic deposition can be applied to produce high-quality P(VDF-TrFE) films on planar as well as three-dimensional (3-D) substrates.« less
Bacchus, Loraine; Mezey, Gillian; Bewley, Susan
2004-03-15
To examine the prevalence of domestic violence (DV) and its associations with obstetric complications and psychological health in women on antenatal and postnatal wards. A cross-sectional survey conducted in an inner-London teaching hospital. Two hundred English-speaking women aged 16 and over, were interviewed between July 2001 and April 2002. The Abuse Assessment Screen was used to assess for experiences of DV. Depression was assessed using the Edinburgh Postnatal Depression Scale (EPDS). The analysis of predictors of obstetric complications grouped together those known to be associated with DV. 23.5% of women had lifetime experience of DV, 3% during the current pregnancy. Women with a history of DV were significantly more likely to be single, separated or in non-cohabiting relationship and to have smoked in the year prior to and/or during pregnancy. Higher EPDS scores were significantly associated with DV, single, separated or non-cohabiting status, and obstetric complications. Both a history of DV and increased EPDS scores were significantly associated with obstetric complications after controlling for other known risk factors. Domestic violence is regarded as an important risk marker for the development of obstetric complications and depressive symptomatology. This finding of itself justifies training and education of maternity health professionals to raise awareness.
Yao, Jianrong; Li, Xirong; Liu, Xinghui; Pang, Meiche
2015-01-01
Aim The aim of this study is to assess the depression of pregnant women in the aftermath of an earthquake, and to identify the social support that they obtained, their coping styles and socio-demographic factors associated with depression. Methods A total of 128 pregnant women from three hospitals in the epicenter area were recruited immediately after the Ya’an earthquake. Their depression was investigated using the Edinburgh Postnatal Depression Scale (EPDS) with a cutoff score of 14; the social support that they obtained was measured using the Social Support Questionnaire; and their coping styles were assessed using the Coping Styles Questionnaire. Results Immediately after the earthquake, the incidence rate of depression in pregnant women was 35.2%, higher than that of the general pregnant population (7%-14%). The EPDS scores were significantly correlated with gestation age at the time of the earthquake, objective support, subjective support, use of support, negative coping style, and positive coping style. The regression analysis indicated that risk factors of prenatal depression include the number of children, relatives wounded, subjective support, and coping styles. A further analysis of the interaction between social support and two types of coping styles with depression showed that there was interaction effect between subjective social support and positive coping styles in relation to EPDS scores. There was an inverse relationship between low EPDS scores and positive coping styles and high social support, and vice versa. Conclusion The timing of the occurrence of the earthquake may not necessarily affect the progress of the illness and recovery from depression, and psychological intervention could be conducted in the immediate aftermath after the earthquake. The impact of coping styles on prenatal depression appeared to be linked with social support. Helping pregnant women to adopt positive coping styles with good social support after a recent major earthquake, which is a stressor, may reduce their chances of developing prenatal depression. PMID:26270035
Tsai, Alexander C.; Scott, Jennifer A.; Hung, Kristin J.; Zhu, Jennifer Q.; Matthews, Lynn T.; Psaros, Christina; Tomlinson, Mark
2013-01-01
Background A major barrier to improving perinatal mental health in Africa is the lack of locally validated tools for identifying probable cases of perinatal depression or for measuring changes in depression symptom severity. We systematically reviewed the evidence on the reliability and validity of instruments to assess perinatal depression in African settings. Methods and Findings Of 1,027 records identified through searching 7 electronic databases, we reviewed 126 full-text reports. We included 25 unique studies, which were disseminated in 26 journal articles and 1 doctoral dissertation. These enrolled 12,544 women living in nine different North and sub-Saharan African countries. Only three studies (12%) used instruments developed specifically for use in a given cultural setting. Most studies provided evidence of criterion-related validity (20 [80%]) or reliability (15 [60%]), while fewer studies provided evidence of construct validity, content validity, or internal structure. The Edinburgh postnatal depression scale (EPDS), assessed in 16 studies (64%), was the most frequently used instrument in our sample. Ten studies estimated the internal consistency of the EPDS (median estimated coefficient alpha, 0.84; interquartile range, 0.71-0.87). For the 14 studies that estimated sensitivity and specificity for the EPDS, we constructed 2 x 2 tables for each cut-off score. Using a bivariate random-effects model, we estimated a pooled sensitivity of 0.94 (95% confidence interval [CI], 0.68-0.99) and a pooled specificity of 0.77 (95% CI, 0.59-0.88) at a cut-off score of ≥9, with higher cut-off scores yielding greater specificity at the cost of lower sensitivity. Conclusions The EPDS can reliably and validly measure perinatal depression symptom severity or screen for probable postnatal depression in African countries, but more validation studies on other instruments are needed. In addition, more qualitative research is needed to adequately characterize local understandings of perinatal depression-like syndromes in different African contexts. PMID:24340036
Murray, Linda; Dunne, Michael P; Van Vo, Thang; Anh, Phuong Nguyen Thi; Khawaja, Nigar G; Cao, Thanh Ngoc
2015-09-30
This study investigated the prevalence and socio-cultural correlates of postnatal mood disturbance amongst women 18-45 years old in Central Vietnam. Son preference and traditional confinement practices were explored as well as factors such as poverty, parity, family and intimate partner relationships and infant health. A cross-sectional study was conducted in twelve randomly selected Commune Health Centres from urban and rural districts of Thua Thien Hue Province, Vietnam. Mother-infant dyads one to six months postpartum were invited to participate. Questionnaires from 431 mothers (urban n = 216; rural n = 215) assessed demographic and family characteristics, traditional confinement practices, son preference, infant health and social capital. The Edinburgh Postnatal Depression Scale (EPDS) and WHO5 Wellbeing Index indicated depressive symptoms and emotional wellbeing. Data were analysed using general linear models. Using an EPDS cut-off of 12/13, 18.1% (n = 78, 95% CI 14.6-22.1) of women had depressive symptoms (20.4% urban; 15.8% rural). Contrary to predictions, infant gender and traditional confinement were unrelated to depressive symptoms. Poverty, food insecurity, being frightened of family members, and intimate partner violence increased both depressive symptoms and lowered wellbeing. The first model accounted for 30.2% of the variance in EPDS score and found being frightened of one's husband, husband's unemployment, breastfeeding difficulties, infant diarrhoea, and cognitive social capital were associated with higher EPDS scores. The second model had accounted for 22% of the variance in WHO5 score. Living in Hue city, low education, poor maternal competence and a negative family response to the baby lowered maternal wellbeing. Traditional confinement practices and son preference were not linked to depressive symptoms among mothers, but were correlates of family relationships and wellbeing. Poverty, food insecurity, violence, infant ill health, and discordant intimate and family relationships were linked with depressive symptoms in Central Vietnam.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Massimino, Maura; Giangaspero, Felice; INM Neuromed, Pozzilli
2006-08-01
Purpose: To discuss the results obtained by giving adjuvant treatment for childhood ependymoma (EPD) at relapse after complete surgery only. Methods and Materials: Between 1993 and 2002, 63 children older than 3 years old entered the first Italian Association for Pediatric Hematology and Oncology protocol for EPD (group A), and another 14 patients were referred after relapsing after more tumor excisions only (group B). Prognostic factors were homogeneously matched in the two groups. We report on the outcome of group B. Results: Mean time to first local progression in group B had been 14 months. Tumors originated in the posteriormore » fossa (PF) in 10 children and were supratentorial (ST) in 4; 11 had first been completely excised (NED) and 3 had residual disease (ED). Diagnoses were classic EPD in 9 patients, anaplastic in 5. Eight children were referred NED and 6 ED after two or more operations, 5 had cranial nerve palsy, 1 had recurrent meningitis, and 2 had persistent hydrocephalus. All received radiotherapy (RT) to tumor bed and 5 also had pre-RT chemotherapy. Six of 14 patients (6/10 with PF tumors) had a further relapse a mean 6 months after the last surgery; 4 of 6 died: progression-free survival and overall survival at 4 years after referral were 54.4% and 77%, respectively. Considering only PF tumors and setting time 0 as at the last surgery for group B, progression-free survival and overall survival were 32% and 50% for group B and 52% (p < 0.20)/70% (p < 0.29) for the 46 patients in group A with PF tumors. Local control was 32% in group B and 70.5% in group A (p = 0.02). Conclusions: Relapsers after surgery only, especially if with PF-EPD, do worse than those treated after first diagnosis; subsequent surgery for tumor relapse has severe neurologic sequelae.« less
Ren, Jianhua; Jiang, Xiaolian; Yao, Jianrong; Li, Xirong; Liu, Xinghui; Pang, Meiche; Chiang, Chung Lim Vico
2015-01-01
The aim of this study is to assess the depression of pregnant women in the aftermath of an earthquake, and to identify the social support that they obtained, their coping styles and socio-demographic factors associated with depression. A total of 128 pregnant women from three hospitals in the epicenter area were recruited immediately after the Ya'an earthquake. Their depression was investigated using the Edinburgh Postnatal Depression Scale (EPDS) with a cutoff score of 14; the social support that they obtained was measured using the Social Support Questionnaire; and their coping styles were assessed using the Coping Styles Questionnaire. Immediately after the earthquake, the incidence rate of depression in pregnant women was 35.2%, higher than that of the general pregnant population (7%-14%). The EPDS scores were significantly correlated with gestation age at the time of the earthquake, objective support, subjective support, use of support, negative coping style, and positive coping style. The regression analysis indicated that risk factors of prenatal depression include the number of children, relatives wounded, subjective support, and coping styles. A further analysis of the interaction between social support and two types of coping styles with depression showed that there was interaction effect between subjective social support and positive coping styles in relation to EPDS scores. There was an inverse relationship between low EPDS scores and positive coping styles and high social support, and vice versa. The timing of the occurrence of the earthquake may not necessarily affect the progress of the illness and recovery from depression, and psychological intervention could be conducted in the immediate aftermath after the earthquake. The impact of coping styles on prenatal depression appeared to be linked with social support. Helping pregnant women to adopt positive coping styles with good social support after a recent major earthquake, which is a stressor, may reduce their chances of developing prenatal depression.
The Energetic Particle Detector Suite for Solar Orbiter
NASA Astrophysics Data System (ADS)
Wimmer-Schweingruber, Robert F.; Rodriguez-Pacheco, J.; Lin, R. P.; Mason, G. M.; Heber, B.; Valtonen, E.; Sanchez, S.; Blanco, J.; Prieto, M.; Martin, C.; Ho, G.; Andrews, B.; Burmeister, S.; Boettcher, S.; Kulkarni, S. R.; Seimetz, L.; Schuster, B.
Multiple processes in the solar atmosphere or near the Sun are capable of energizing electrons and ions which are remotely observed as Solar Energetic Particle (SEP) events. SEP events are of great interest not only because they can cause large radiation increases in the interplanetary space and over the Earth's polar regions, but also because they are part of a broad range of astrophysical sources of energetic particles. Since astrophysical particle accelerators cannot be studied directly, SEPs provide the best opportunity to study all aspects of the problem, namely the acceleration process itself and the ways in which the particles escape the source and travel to remote sites. The Energetic Particle Detector (EPD) addresses two primary science goals of Solar Orbiter: 1) What are the sources of energetic particles and how are they accelerated to high energy? 2) How are solar energetic particles released from their sources and distributed in time? To address these questions, the Energetic Particle Detector (EPD) suite consists of five sensors measuring electrons, protons, and ions from helium to iron, and operating at partly overlapping energy ranges from 2 keV up to 200 MeV/n. The five EPD sensors are the SupraThermal Elec-trons, Ions, Neutrals (STEIN) sensor, the Suprathermal Ion Spectrograph (SIS), the Electron Proton Telescope (EPT), the Low Energy Telescope (LET), and the High Energy Telescope (HET). All sensors share a Common Data Processing Unit (CDPU), and EPT and HET share a common E-Box. EPT/HET and LET consist of two separate sensors with multiple viewing directions. The overall energy coverage achieved with the EPD sensors is 0.002 MeV to 20 MeV for electrons, 0.003 MeV to 100 MeV for protons, 0.008 MeV/n to 200 MeV/n for heavy ions (species-dependent), and 3 keV 30 keV for neutral atoms.
NASA Astrophysics Data System (ADS)
Ravanbakhsh, A.; Kulkarni, S. R.; Panitzsch, L.; L Richards, M.; Munoz Hernandez, A.; Seimetz, L.; Elftmann, R.; Mahesh, Y.; Boden, S.; Boettcher, S. I.; Kulemzin, A.; Martin-Garcia, C.; Prieto, M.; Rodriguez-Pacheco, J.; Sanchez Prieto, S.; Schuster, B.; Steinhagen, J.; Tammen, J.; Wimmer-Schweingruber, R. F.
2016-12-01
Solar Orbiter is ESA's next solar and heliospheric mission which is planned to be launched in October 2018. The Energetic Particle Detector (EPD) on board on Solar Orbiter will provide key measurements for the Solar Orbiter science objectives. The EPD suite consists of four sensors; STEP, SIS, EPT and HET. The University of Kiel in Germany is responsible for the design, development, and building of STEP, and the two identical units EPT-HET 1 and EPT-HET 2. ESA's Solar Orbiter will explore the heliosphere at heliocentric distances between 0.28AU and 0.9AU and with inclination up to 38deg with respect to the Sun's equator. The spacecraft uses a heat shield to protect the bus and externally mounted instruments from the solar flux at the close distances to the sun. All three EPD-Kiel units are mounted externally but in different positions on the spacecraft outer deck. Although being protected by the spacecraft heat shield from high solar flux, EPT-HET1 and EPT-HET-2 as well as STEP experience a harsh environmental condition during the course of the mission. In addition due to the highly demanding science requirements, the qualification and acceptance test requirements of these externally mounted units are quite challenging. In this paper we present the development status of the EPT-HET 1, EPT-HET 2 and STEP sensors focusing on the activities performed in phase D and the qualification and acceptance test campaigns. The main objective of these test campaigns is to ensure and demonstrate the compatibility between the scientific requirements and the harsh environment expected during the mission. This paper includes the results summary of the environmental tests on the EPT-HET and STEP Proto-Qualification Models (PQMs) as well as Proto-Flight Models (PFMs). Only an adequate selection of environmental qualification and acceptance campaigns will guarantee the success of the scientific space missions.
Engineer, Neelam; Darwin, Lucy; Nishigandh, Deole; Ngianga-Bakwin, Kandala; Smith, Steve C; Grammatopoulos, Dimitris K
2013-09-01
Women with postnatal depression (PND) appear to have abnormal hypothalamic pituitary adrenal (HPA) axis responses to stress, which might involve a genetic variability component. We investigated association of genetic variants in the glucocorticoid receptor (GR, NR3C1) and corticotropin releasing hormone receptor 1 (CRHR1) genes with increased risk for PND. Two hundred pregnant women were recruited prospectively and PND risk was assessed by the Edinburgh Postnatal Depression Scale (EPDS) during pregnancy and again 2-8 weeks post-natally (CW-GAPND study). The BclI and ER22/23EK single nucleotide polymorphisms (SNPs) of the GR and the haplotype-tagged rs1876828, rs242939 and rs242941 SNPs of the CRHR1 associated with genetic risk to depressive disorders were genotyped. A cut-off score of 10 was used to detect increased risk of PND. Association analysis was carried out in 140 patients that completed the study protocol. The BclI and rs242939 SNPs were over-represented in women with postnatal EPDS score ≥10 with significant allele association (p = 0.011 and <0.001, respectively) and risk ratios of 2.9 (95% CI: 1.2-6.9) for BclI, 4.9 (2-12) for rs242939 and 5.48 (2.13-14.10) for both. The rs242939 SNP was also associated with increased EPDS values during pregnancy. Moreover, the G-G-T haplotype of the CRHR1 was significantly over-represented in patients with high EPDS scores, with risk ratio of 3.22 (95% CI: 1.91-5.42). This is the first evidence that specific SNPs of genes involved in 'stress' responses might contribute in the genetics of high-risk for depression during pregnancy and postpartum. Copyright © 2013 Elsevier Ltd. All rights reserved.
[Detection, prevention and treatment of postpartum depression: a controlled study of 859 patients].
Chabrol, H; Teissedre, F; Saint-Jean, M; Teisseyre, N; Sistac, C; Michaud, C; Roge, B
2002-01-01
This study evaluated the clinical effectiveness of a programme aimed at detecting, preventing and treating postpartum depression. The French version of the EPDS was used to measure the intensity of postpartum blues on a sample of 859 women, during their stay at the obstetrical clinic. Subjects under treatment for psychological problems were excluded from the study. Mothers scoring 9 or above on the EPDS, which is predictive of pospartum depression, were randomly assigned to a prevention and a control group. Written informed consent was obtained from the subjects after the study procedure had been explained. The prevention group received a counselling session integrating supportive, educational and cognitive-behavioral components. Therapists included five female Master's Degree level students in psychology. All therapists participated in didactic and clinical training as wells as weekly supervision from the first author. All subjects were given a second EPDS with written instructions to complete the questionnaire during the period 4 to 6 weeks postpartum and return it for analysis. At four to 6 weeks, women in the prevention group had significant reductions in the frequency of probable depression, as defined by a score of 11 or above on the EPDS (30.2% vs 48.2%, chi 2 = 7.36, dl = 1, p = 0.0067) and in the intensity of depressive symptoms measured by the mean score on the EPDS (8.5, SD = 4 vs 10.3, SD = 4.4, t = 3.06, dl = 209, p = 0.0024). Mothers with a probable depression were interviewed at home and assessed using the MINI (Mini Neuropsychiatric Interview, Lecrubier et al., 1997) to diagnose major depressive episode, the SIGH-D (Structured Interview Guide for the Hamilton Depression Rating Scale, Williams, 1988) and the BDI (Beck Depression Inventory, Beck et al., 1988). The baseline depression rating scores, EPDS (mean = 13.6, SD = 4), BDI (mean = 15.7, SD = 5.9), HDRS (mean = 14.8, SD = 6), were consistent with moderate depression. No significant differences in baseline scores were observed between the two groups on all the rating scales (p < 0.001). Mothers with probable depression in the prevention group were offered a program of 5 to 8 home visits. Most of the mothers in the prevention group (72%) agreed to participate in the program. On the contrary, most of the mothers (83.3%) who scored below 9 on the first EPDS and 11 or above on the second, who so did not received the preventive counselling session, declined to participate. This suggests the importance of the preventive session in establishing therapeutic alliance. The home visits program integrated four components, supportive, educational, cognitive-behavioral and psychodynamic centred on the mother-infant relationship in terms of the mother's personal history. Therapist participated in clinical training and weekly supervision. Fifteen women (71.4%) in the study group demonstrated complete symptom remission, as defined by HDRS score below 7 after the intervention, compared with 4 women (10.5%) in the control group (chi 2 = 23, p < 0.0001). A clearly therapeutic response to treatment was observed in the treated group with a mean reduction in HDRS score of 9.5 (DS = 6.7) from baseline. The improvement in the women in the treated group, as measured by the mean HDRS scores was statistically greater than that in the control group (m = 5.35, SD = 3.5 vs m = 15.8, SD = 4.6, t = 8.24, dl = 52, p < 0.0001). Our results indicate that a program based on an intervention at obstetrical clinics and on home visits is efficacious and well accepted for prevention, detection and treatment of postpartum depression.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brandt, C.A.; Rickard, W.H. Jr.; Hefty, M.G.
This report describes the development of the reclamation project for the Hanford Site Near Surface Test Facility (NSTF), its implementation, and preliminary estimates of its success. The goal of the reclamation project is to return disturbed sites as nearly as practicable to their original conditions using native species. Gable Mountain is dominated by two plant communities: a big sagebrush (Artemisia tridentata) -- Sandberg's bluegrass (Poa sandbergii) community and a stiff sagebrush (Artemisia rigida) -- Sandberg's bluegrass community. Disassembly of the site installations began on March 15, 1988, and the site was returned to original contours by December 12, 1988. Twomore » separate revegetation methods were employed at the NSTF to meet differing site constraints. Vegetative cover and density in the revegetation plots were assessed in April 1989 and again in June 1989 and 1990. It is extremely unlikely that the sand pit, borrow pit, box cuts, generator pad area, or ventilation fan area will reach the reclamation objectives set for these areas within the next 50 years without further intervention. These areas currently support few living plants. Vegetation on revegetated native soils appears to be growing as expected. Vegetation growth on the main waterline is well below the objective. To date, no shrubs have grown on the area, growth of native grasses is well below the objective, and much of the area has been covered with the pit run material, which may not support adequate growth. Without further treatments, the areas without the pit run material will likely revert to a nearly pure cheatgrass condition. 44 refs., 13 figs., 7 tabs.« less
Crystal growth and dislocation etch pits observation of chalcopyrite CdSiP2
NASA Astrophysics Data System (ADS)
He, Zhiyu; Zhao, Beijun; Zhu, Shifu; Chen, Baojun; Huang, Wei; Lin, Li; Feng, Bo
2018-01-01
CdSiP2 is the only crystal that can offer Non-critical Phase Matching (NCPM) for a 1064 nm pumped optical parametric oscillation (OPO) with idler output in the 6 μm range. In this paper, a large, crack-free CdSiP2 single crystal measuring 18 mm in diameter and 65 mm in length was successfully grown by the Vertical Bridgman method (MVB) with an explosion-proof quartz ampoule. The results of lattice parameters, element composition and IR transmittance of the as-grown crystal characterized by X-ray diffraction (XRD), energy dispersive X-ray spectrometer (EDS) and Fourier transformation infrared spectrometer (FTIR) showed the as grown crystal crystallized well and the absorption coefficients at 4878 cm-1 and 2500 cm-1 were 0.14 cm-1 and 0.06 cm-1. Moreover, a new etchant composed of Br2, HCl, HNO3, CH3OH and H2O (1:800:800:400:400 in volume ratio) was prepared and the dislocation etch pits on oriented faces of as-grown CdSiP2 crystal were observed for the first time. It is found the etch pits are in rectangular structure on the (1 0 1) face, but in trigonal pyramid structure on (3 1 2) face. According to the quantities of the etch pits, the average densities of dislocation were evaluated to be 2.28 × 105/cm2 and 1.4 × 105/cm2, respectively.
Microbial Diversity in Natural Asphalts of the Rancho La Brea Tar Pits▿
Kim, Jong-Shik; Crowley, David E.
2007-01-01
Bacteria commonly inhabit subsurface oil reservoirs, but almost nothing is known yet about microorganisms that live in naturally occurring terrestrial oil seeps and natural asphalts that are comprised of highly recalcitrant petroleum hydrocarbons. Here we report the first survey of microbial diversity in ca. 28,000-year-old samples of natural asphalts from the Rancho La Brea Tar Pits in Los Angeles, CA. Microbiological studies included analyses of 16S rRNA gene sequences and DNA encoding aromatic ring-hydroxylating dioxygenases from two tar pits differing in chemical composition. Our results revealed a wide range of phylogenetic groups within the Archaea and Bacteria domains, in which individual taxonomic clusters were comprised of sets of closely related species within novel genera and families. Fluorescent staining of asphalt-soil particles using phylogenetic probes for Archaea, Bacteria, and Pseudomonas showed coexistence of mixed microbial communities at high cell densities. Genes encoding dioxygenases included three novel clusters of enzymes. The discovery of life in the tar pits provides an avenue for further studies of the evolution of enzymes and catabolic pathways for bacteria that have been exposed to complex hydrocarbons for millennia. These bacteria also should have application for industrial microbiology and bioremediation. PMID:17416692
Dennis, Cindy-Lee; Vigod, Simone
2013-04-01
The objective of this study was to determine the contribution of interpersonal violence and substance use to the prediction of postpartum depressive symptomatology. A community-based sample of 634 women in British Columbia, Canada was screened for interpersonal violence and substance use using the Antenatal Psychosocial Health Assessment (ALPHA) form. Of these women, 497 (78%) subsequently completed questionnaires at 8 weeks postpartum to assess for depressive symptomatology using the Edinburgh Postnatal Depression Scale (EPDS). A predictive model for postpartum depressive symptomatology (EPDS > 9) was developed using regression analysis. Findings suggest that women who experience past or current interpersonal violence or personal or partner substance use problems should be considered for targeted screening for postpartum depression (PPD).
Influence of socio-economic factors on emotional changes during the postnatal period.
Wszołek, Katarzyna; Żak, Ewa; Żurawska, Joanna; Olszewska, Jolanta; Pięta, Beata; Bojar, Iwona
2018-03-14
The aim of the study was to identify socio-economic factors that may influence the emotional changes which occur among new mothers in the first days postpartum. A group of 541 women completed a questionnaire consisting of 30 multiple-choice questions, Edinburgh Postnatal Depression Scale (EPDS), and Hospital Anxiety and Depression Scale (HADS). Statistical calculations were performed with the use of Statistica v.10 and Cytel Studio v. 9.0.0. The findings revealed the presence of factors which might increase the risk of mood disorders during the postpartum period. Women who demonstrate warning symptoms should be screened for postnatal emotional changes and mood swings during their hospitalization after delivery. EPDS seems to be a suitable tool for early detection of emotional disturbances.
Electrochemical properties of 316L stainless steel with culturing L929 fibroblasts
Hiromoto, Sachiko; Hanawa, Takao
2005-01-01
Potentiodynamic polarization and impedance tests were carried out on 316L stainless steel with culturing murine fibroblast L929 cells to elucidate the corrosion behaviour of 316L steel with L929 cells and to understand the electrochemical interface between 316L steel and cells, respectively. Potential step test was carried out on 316L steel with type I collagen coating and culturing L929 cells to compare the effects of collagen and L929 cells. The open-circuit potential of 316L steel slightly shifted in a negative manner and passive current density increased with cells, indicating a decrease in the protective ability of passive oxide film. The pitting potential decreased with cells, indicating a decrease in the pitting corrosion resistance. In addition, a decrease in diffusivity at the interface was indicated from the decrease in the cathodic current density and the increase in the diffusion resistance parameter in the impedance test. The anodic peak current in the potential step test decreased with cells and collagen. Consequently, the corrosion resistance of 316L steel decreases with L929 cells. In addition, collagen coating would provide an environment for anodic reaction similar to that with culturing cells. PMID:16849246
Laurence, T. A.; Ly, S.; Shen, N.; ...
2017-06-22
Laser-induced damage with ps pulse widths straddles the transition from intrinsic, multi-photon ionization and avalanche ionization-based ablation with fs pulses to defect-dominated, thermal-based damage with ns pulses. We investigated the morphology of damage for fused silica and silica coatings between 1 ps and 60 ps at 1053 nm. Using calibrated laser-induced damage experiments, in situ imaging, and high-resolution optical microscopy, atomic force microscopy, and scanning electron microscopy, we show that defects play an important role in laser-induced damage down to 1 ps. Three types of damage are observed: ablation craters, ultra-high density pits, and smooth, circular depressions with central pits.more » For 10 ps and longer, the smooth, circular depressions limit the damage performance of fused silica and silica coatings. The observed high-density pits and material removal down to 3 ps indicate that variations in surface properties limit the laser-induced damage onset to a greater extent than expected below 60 ps. Below 3 ps, damage craters are smoother although there is still evidence as seen by AFM of inhomogeneous laser-induced damage response very near the damage onset. These results show that modeling the damage onset only as a function of pulse width does not capture the convoluted processes leading to laser induced damage with ps pulses. It is necessary to account for the effects of defects on the processes leading to laser-induced damage. In conclusion, the effects of isolated defects or inhomogeneities are most pronounced above 3 ps but are still discernible and possibly important down to the shortest pulse width investigated here.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laurence, T. A.; Ly, S.; Shen, N.
Laser-induced damage with ps pulse widths straddles the transition from intrinsic, multi-photon ionization and avalanche ionization-based ablation with fs pulses to defect-dominated, thermal-based damage with ns pulses. We investigated the morphology of damage for fused silica and silica coatings between 1 ps and 60 ps at 1053 nm. Using calibrated laser-induced damage experiments, in situ imaging, and high-resolution optical microscopy, atomic force microscopy, and scanning electron microscopy, we show that defects play an important role in laser-induced damage down to 1 ps. Three types of damage are observed: ablation craters, ultra-high density pits, and smooth, circular depressions with central pits.more » For 10 ps and longer, the smooth, circular depressions limit the damage performance of fused silica and silica coatings. The observed high-density pits and material removal down to 3 ps indicate that variations in surface properties limit the laser-induced damage onset to a greater extent than expected below 60 ps. Below 3 ps, damage craters are smoother although there is still evidence as seen by AFM of inhomogeneous laser-induced damage response very near the damage onset. These results show that modeling the damage onset only as a function of pulse width does not capture the convoluted processes leading to laser induced damage with ps pulses. It is necessary to account for the effects of defects on the processes leading to laser-induced damage. In conclusion, the effects of isolated defects or inhomogeneities are most pronounced above 3 ps but are still discernible and possibly important down to the shortest pulse width investigated here.« less
DCMDN: Deep Convolutional Mixture Density Network
NASA Astrophysics Data System (ADS)
D'Isanto, Antonio; Polsterer, Kai Lars
2017-09-01
Deep Convolutional Mixture Density Network (DCMDN) estimates probabilistic photometric redshift directly from multi-band imaging data by combining a version of a deep convolutional network with a mixture density network. The estimates are expressed as Gaussian mixture models representing the probability density functions (PDFs) in the redshift space. In addition to the traditional scores, the continuous ranked probability score (CRPS) and the probability integral transform (PIT) are applied as performance criteria. DCMDN is able to predict redshift PDFs independently from the type of source, e.g. galaxies, quasars or stars and renders pre-classification of objects and feature extraction unnecessary; the method is extremely general and allows the solving of any kind of probabilistic regression problems based on imaging data, such as estimating metallicity or star formation rate in galaxies.
Crouthamel, Matthew H.; Lau, Wei Ling; Leaf, Elizabeth M.; Chavkin, Nick; Wallingford, Mary C.; Peterson, Danielle F.; Li, Xianwu; Liu, Yonggang; Chin, Michael T.; Levi, Moshe; Giachelli, Cecilia M.
2014-01-01
Objective Elevated serum phosphate has emerged as a major risk factor for vascular calcification. The sodium-dependent phosphate cotransporter, PiT-1, was previously shown to be required for phosphate-induced osteogenic differentiation and calcification of cultured human VSMCs, but its importance in vascular calcification in vivo, as well as the potential role of its homologue, PiT-2, have not been determined. We investigated the in vivo requirement for PiT-1 in vascular calcification using a mouse model of chronic kidney disease, and the potential compensatory role of PiT-2 using in vitro knockdown and over-expression strategies. Approach and Results Mice with targeted deletion of PiT-1 in VSMCs were generated (PiT-1Δsm). PiT-1 mRNA levels were undetectable whereas PiT-2 mRNA levels were increased 2 fold in the vascular aortic media of PiT-1Δsm compared to PiT-1flox/flox control. When arterial medial calcification was induced in PiT-1Δsm and PiT-1flox/flox by chronic kidney disease followed by dietary phosphate loading, the degree of aortic calcification was not different between genotypes, suggesting compensation by PiT-2. Consistent with this possibility, VSMCs isolated from PiT-1Δsm mice had no PiT-1 mRNA expression, increased PiT-2 mRNA levels, and no difference in sodium-dependent phosphate uptake or phosphate-induced matrix calcification compared to PiT-1flox/flox VSMCs. Knockdown of PiT-2 decreased phosphate uptake and phosphate-induced calcification of PiT-1Δsm VSMCs. Furthermore, over-expression of PiT-2 restored these parameters in human PiT-1-deficient VSMCs. Conclusions PiT-2 can mediate phosphate uptake and calcification of VSMCs in the absence of PiT-1. Mechanistically, PiT-1 and PiT-2 appear to serve redundant roles in phosphate-induced calcification of vascular smooth muscle cells. PMID:23968976
A Micro-Mechanism-Based Continuum Corrosion Fatigue Damage Model for Steels
NASA Astrophysics Data System (ADS)
Sun, Bin; Li, Zhaoxia
2018-05-01
A micro-mechanism-based corrosion fatigue damage model is developed for studying the high-cycle corrosion fatigue of steel from multi-scale viewpoint. The developed physical corrosion fatigue damage model establishes micro-macro relationships between macroscopic continuum damage evolution and collective evolution behavior of microscopic pits and cracks, which can be used to describe the multi-scale corrosion fatigue process of steel. As a case study, the model is used to predict continuum damage evolution and number density of the corrosion pit and short crack of steel component in 5% NaCl water under constant stress amplitude at 20 kHz, and the numerical results are compared with experimental results. It shows that the model is effective and can be used to evaluate the continuum macroscopic corrosion fatigue damage and study microscopic corrosion fatigue mechanisms of steel.
A Micro-Mechanism-Based Continuum Corrosion Fatigue Damage Model for Steels
NASA Astrophysics Data System (ADS)
Sun, Bin; Li, Zhaoxia
2018-04-01
A micro-mechanism-based corrosion fatigue damage model is developed for studying the high-cycle corrosion fatigue of steel from multi-scale viewpoint. The developed physical corrosion fatigue damage model establishes micro-macro relationships between macroscopic continuum damage evolution and collective evolution behavior of microscopic pits and cracks, which can be used to describe the multi-scale corrosion fatigue process of steel. As a case study, the model is used to predict continuum damage evolution and number density of the corrosion pit and short crack of steel component in 5% NaCl water under constant stress amplitude at 20 kHz, and the numerical results are compared with experimental results. It shows that the model is effective and can be used to evaluate the continuum macroscopic corrosion fatigue damage and study microscopic corrosion fatigue mechanisms of steel.
Nobody’s perfect: can irregularities in pit structure influence vulnerability to cavitation?
Plavcová, Lenka; Jansen, Steven; Klepsch, Matthias; Hacke, Uwe G.
2013-01-01
Recent studies have suggested that species-specific pit properties such as pit membrane thickness, pit membrane porosity, torus-to-aperture diameter ratio and pit chamber depth influence xylem vulnerability to cavitation. Despite the indisputable importance of using mean pit characteristics, considerable variability in pit structure within a single species or even within a single pit field should be acknowledged. According to the rare pit hypothesis, a single pit that is more air-permeable than many neighboring pits is sufficient to allow air-seeding. Therefore, any irregularities or morphological abnormalities in pit structure allowing air-seeding should be associated with increased vulnerability to cavitation. Considering the currently proposed models of air-seeding, pit features such as rare, large pores in the pit membrane, torus extensions, and plasmodesmatal pores in a torus can represent potential glitches. These aberrations in pit structure could either result from inherent developmental flaws, or from damage caused to the pit membrane by chemical and physical agents. This suggests the existence of interesting feedbacks between abiotic and biotic stresses in xylem physiology. PMID:24273549
The STAR Detector Upgrades and Electromagnetic Probes in Beam Energy Scan Phase II
NASA Astrophysics Data System (ADS)
Yang, Chi
The Beam Energy Scan Phase II at RHIC, BES-II, is scheduled from year 2019 to 2020 and will explore the high baryon density region of the QCD phase diagram with high precision. The program will focus on the interesting energy region determined from the results of BES-I. Some of the key measurements anticipated are the chiral symmetry restoration and QGP thermal radiation in the dilepton and direct photon channels. The measurements will be possible with an order of magnitude better statistics provided by the electron cooling upgrade of RHIC and with the detector upgrades planned to extend STAR experimental reach. The upgrades are: the inner Time Projection Chamber sectors (iTPC), the Event Plane Detector (EPD), and the end-cap Time of Flight (eTOF). We present the BES-II program details and the physics opportunities in the dilepton and direct photon channels enabled by the upgrades.
Breastfeeding and Postnatal Depression: A Prospective Cohort Study in Sabah, Malaysia.
Yusuff, Aza Sherin Mohamad; Tang, Li; Binns, Colin W; Lee, Andy H
2016-05-01
Postnatal depression is a disorder that can lead to serious consequences for both the mother and infant. Despite the extensively documented health benefits of breastfeeding, its association with postnatal depression remains uncertain. To investigate the relationship between full breastfeeding at 3 months postpartum and postnatal depressive symptoms among mothers in Sabah, Malaysia. A prospective cohort study of 2072 women was conducted in Sabah during 2009-2010. Participants were recruited at 36 to 38 weeks of gestation and followed up at 1 and 3 months postpartum. Depressive symptoms were assessed using the validated Malay version of the Edinburgh Postnatal Depression Scale (EPDS). Repeated-measures analyses of variance was performed to compare the depression scores over time and between subgroups of breastfeeding mothers. Approximately 46% of women were fully breastfeeding their infants at 3 months postpartum. These mothers had significantly (P < .001) lower mean EPDS scores at both 1 and 3 months postpartum (mean ± SD, 4.14 ± 4.12 and 4.27 ± 4.12, respectively) than others who did not initiate or maintain full breastfeeding for 3 months (4.94 ± 4.34 and 5.25 ± 4.05, respectively). After controlling for the effects of covariates, the differences in EPDS scores remained statistically significant (P = .001) between the 2 breastfeeding groups. Full breastfeeding appeared to be negatively associated with postnatal depressive symptoms for mothers residing in Sabah. © The Author(s) 2015.
Electrophoretic assembly of organic molecules and composites for electrochemical supercapacitors.
Su, Y; Zhitomirsky, I
2013-02-15
Electrophoretic deposition (EPD) method has been developed for the fabrication of 1-pyrenebutyric acid (PBH) films from aqueous solutions. The films can be deposited at constant voltage or potentiodynamic conditions. The method allowed the formation of 0.1-2 μm thick films, containing needle-shape PBH particles. The deposition mechanism involved the electrophoresis, pH decrease at the anode surface, charge neutralization and formation of insoluble PBH films. The film morphology and shape of the PBH particles are controlled by the π-π stacking mechanism of the polyaromatic PBH molecules. The important finding was the possibility of controlled EPD of multiwalled carbon nanotubes (MWCNTs) using PBH as a charging, dispersing and film forming agent. It was found that at low voltages or low PBH concentrations the deposits contained mainly MWCNT. The increase in the deposition voltage or/and PBH concentration resulted in co-deposition of MWCNT and needle-shape PBH particles. The new approach to the deposition of MWCNT was used for the fabrication of composite MnO(2)-MWCNT films for electrodes of electrochemical supercapacitors, which showed a specific capacitance of 250 F g(-1). The EPD method developed in this investigation paves the way for the deposition of other small organic molecules and composites and their applications in new materials and devices, utilizing functional properties of the organic molecules, CNT, and other advanced materials. Copyright © 2012 Elsevier Inc. All rights reserved.
Screening for postpartum depression using Kurdish version of Edinburgh postnatal depression scale.
Ahmed, Hamdia Mirkhan; Alalaf, Shahla Kareem; Al-Tawil, Namir Ghanim
2012-05-01
One of the important public health problems affecting maternal and child health is postpartum depression (PPD). It generally occurs within 6-8 weeks after childbirth. To determine the prevalence of postpartum depression (PPD) using a Kurdish version of Edinburgh postpartum depression scale (EPDS) and to analyze the risk factors for postpartum depression in a population of puerperal Kurdish women in Erbil city. A cross-sectional study was conducted between 20th of June and 30th of November 2010, in 14 antenatal care units of primary health centers, in Erbil city, Kurdistan region, Iraq. The sample of the study included 1,000 puerperal women (6-8 weeks postpartum), ranging in age from 14 to 48 years. Data were collected after interviewing the women using a questionnaire designed by the researchers, and the Kurdish version of the EPDS. Chi square test of association and the logistic regression tests were used in the analysis. The prevalence of postpartum depression was 28.4%. Logistic regression analysis showed that the factors found to be associated with PPD were: physical or sexual abuse, delivery by cesarean section, history of past psychiatric illness, and family history of past psychiatric illness; while marriage with no previous agreement, and high socio-economic level were associated with lower levels of PPD. The Kurdish version of the EPDS can be successfully used to screen depression in a Kurdish population of puerperal women.
Kozinszky, Zoltan; Töreki, Annamária; Hompoth, Emőke A; Dudas, Robert B; Németh, Gábor
2017-04-01
We endeavoured to analyze the factor structure of the Edinburgh Postnatal Depression Scale (EPDS) during a screening programme in Hungary, using exploratory (EFA) and confirmatory factor analysis (CFA), testing both previously published models and newly developed theory-driven ones, after a critical analysis of the literature. Between April 2011 and January 2015, a sample of 2967 pregnant women (between 12th and 30th weeks of gestation) and 714 women 6 weeks after delivery completed the Hungarian version of the EPDS in South-East Hungary. EFAs suggested unidimensionality in both samples. 33 out of 42 previously published models showed good and 6 acceptable fit with our antepartum data in CFAs, whilst 10 of them showed good and 28 acceptable fit in our postpartum sample. Using multiple fit indices, our theory-driven anhedonia (items 1,2) - anxiety (items 4,5) - low mood (items 8,9) model provided the best fit in the antepartum sample. In the postpartum sample, our theory-driven models were again among the best performing models, including an anhedonia and an anxiety factor together with either a low mood or a suicidal risk factor (items 3,6,10). The EPDS showed moderate within- and between-culture invariability, although this would also need to be re-examined with a theory-driven approach. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.
[Maternal attachment patterns and personality in post partum depression].
Aceti, Franca; Baglioni, Valentina; Ciolli, Paola; De Bei, Francesco; Di Lorenzo, Flavia; Ferracuti, Stefano; Giacchetti, Nicoletta; Marini, Isabella; Meuti, Valentina; Motta, Paola; Roma, Paolo; Zaccagni, Michela; Williams, Riccardo
2012-01-01
This study investigates the prevalence of post partum depression (PPD) in a sample of Roman women, and the role of socio-demographic variables, personality structure and maternal attachment patterns, in order to identify primary and secondary prevention strategies. Data were collected in two phases. During the third trimester of pregnancy, a sample of 453 women completed a socio-demographic data sheet and the Edinburgh Postnatal Depression Scale (EPDS). Among the patients scoring 12 or more at EPDS, 15 entered the second phase of the study and completed SCID-II and Adult Attachment Interview. PPD diagnosis was confirmed by the SCID-I. The study group was compared with a control group. Among the 453 women who were evaluated, 92 (20.3%) scored ≥12 at EPDS, 39 has been enrolled and 15 entered the study. Presence of depressive symptoms was associated with: complications in pregnancy, previous psychiatric disorders, family and marital conflicts. 66.6% of depressed mothers showed more than one diagnosis on Axis II (particularly avoidant/dependent + borderline or histrionic + dependent). The AAI showed a prevalence of insecure (33.3%) and unresolved/disorganized (46.6%) attachment pattern in the clinical group. Our results suggest that psychological factors such as personality structure and attachment patterns are not only involved in post natal affective disorders, but have a key role in the onset and development of PPD.
Shi, Y Y; Li, M; Liu, Q; Jia, Z J; Xu, X C; Cheng, Y; Zheng, Y F
2016-03-01
Electrophoretic deposition (EPD) is a facile and feasible technique to prepare functional nanocomposite coatings for application in orthopedic-related implants. In this work, a ternary graphene oxide-chitosan-hydroxyapatite (GO-CS-HA) composite coating on Ti substrate was successfully fabricated by EPD. Coating microstructure and morphologies were investigated by scanning electron microscopy, contact angle test, Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetric analysis. It was found GO-CS surface were uniformly decorated by HA nanoparticles. The potentiodynamic polarization test in simulated body fluid indicated that the GO-CS-HA coatings could provide effective protection of Ti substrate from corrosion. This ternary composite coating also exhibited good biocompatibility during incubation with MG63 cells. In addition, the nanocomposite coatings could decrease the attachment of Staphylococcus aureus.
Petrozzi, Angela; Gagliardi, Luigi
2016-01-01
Psychological factors can influence breast-feeding. We translated into Italian and validated the Breastfeeding Self-Efficacy Scale Short Form (BSES-SF) and investigated its predictive ability and its relation with postpartum depression symptoms.BSES-SF and Edinburgh Postnatal Depression Scale (EPDS) were administered 2 to 3 days after delivery to 122 mothers. Breast-feeding was assessed at 3 months.The BSES-SF displayed good validity (receiver operating characteristic area = 0.69) for predicting full breast-feeding at 3 months. In multivariate analysis, the probability of full breast-feeding increased 2.4% for 1-point increase of BSES-SF. The BSES-SF and EPDS scores were inversely correlated. BSES-SF is a useful tool to identify the risk of early breast-feeding attrition.
Mechanism and kinetics of electrophoretic deposition of Al{sub 2}O{sub 3}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarkar, P.; Nicholson, P.S.
1996-06-01
The four main electrophoretic deposition (EPD) mechanisms are discussed and their shortcomings pointed out. The Hamaker constant for Al{sub 2}O{sub 3} in ethanol suspension is determined by modelling the relationship between particle interaction energy and suspension stability. The Derjagun-Landau-Verwey-Overbeek (DLVO) interaction energy curve for Al{sub 2}O{sub 3} particles in ethanol suspension is calculated and the minimum deposition voltage determined. Three probe dc measurements were conducted to explain discrepancies between the calculated and experimentally-observed voltage. A mechanism proposed is based on the DLVO theory and particle-lyosphere destortion/thinning. Kinetic equations for EPD are developed for constant current and constant voltage deposition usingmore » mass balance conditions and verified by experimental data.« less
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. Volume 2 continues the presentation of IOA worksheets.
NASA Astrophysics Data System (ADS)
Baerwolff, A.; Enders, P.; Knauer, A.; Linke, D.; Zeimer, U.
1988-11-01
It is shown that the yield of fault-free laser diodes is related to the density and distribution of dislocations in the substrate. A method is described for visualization of etch pits and of their relationship to defects in the substrate.
D.W. Johnson; C.T. Hunsaker; D.W. Glass; B.M. Rau; B.A. Roath
2011-01-01
Soil C and nutrient contents were estimated for eight watersheds in two sites (one high elevation, Bull, and one low elevation, Providence) in the Kings River Experimental Watersheds in the western Sierra Nevada Mountains of California. Eighty-seven quantitative pits were dug to measure soil bulk density and total rock content, while three replicate surface samples...
Evaluating Interannual Variability of Accumulation Gradients on the Juneau Icefield
NASA Astrophysics Data System (ADS)
Koncewicz, E.; Bollen, K.; Burkhart, A.; Cabrera, V.; Rovzar, T.; Truax, O.; McNeil, C.; Nicholson, L. I.; O'Neel, S.
2016-12-01
The Juneau Icefield Research Program has collected mass balance data over the last 70 years on the Taku and Lemon Creek glaciers. We analyze data from 2004-2016 to investigate the interannual variability in the accumulation gradients of these two glaciers from ground penetrating radar (GPR), probing, and snow pits. Understanding interannual variability of accumulation gradients on the Juneau Icefield will help us to interpret its long-term mass balance record. The Lemon Creek Glacier is a small valley glacier on the southwest edge of the Icefield. GPR data was collected over the glacier surface in March 2015 and 2016. In July of 2014 and 2016, the accumulation area was probed for snow depth, and two snow pits were dug for snow depth and density. The accumulation gradients resulting from each method are compared between years to assess the interannnual variability of the accumulation gradient and the resulting glacier wide mass balance. The Taku Glacier is the largest outlet glacier on the Juneau Icefield. We use three snow pits dug each year along the longitudinal profile of the glacier between 1000m and 1115m, the region that typically reflects the ELA. In 2004, 2005, 2010, 2011, and 2016, snow probing was continued in the central region of the Taku and the resulting gradients are compared to each other and to the gradients derived from the snow pits. We assess the resulting impact on glacier wide mass balance furthering our understanding of the state of these two well-monitored glaciers on the Juneau Icefield.
Apollo 12 Lunar Module exhaust plume impingement on Lunar Surveyor III
NASA Astrophysics Data System (ADS)
Immer, Christopher; Metzger, Philip; Hintze, Paul E.; Nick, Andrew; Horan, Ryan
2011-02-01
Understanding plume impingement by retrorockets on the surface of the Moon is paramount for safe lunar outpost design in NASA's planned return to the Moon for the Constellation Program. Visual inspection, Scanning Electron Microscopy, and surface scanned topology have been used to investigate the damage to the Lunar Surveyor III spacecraft that was caused by the Apollo 12 Lunar Module's close proximity landing. Two parts of the Surveyor III craft returned by the Apollo 12 astronauts, Coupons 2050 and 2051, which faced the Apollo 12 landing site, show that a fine layer of lunar regolith coated the materials and was subsequently removed by the Apollo 12 Lunar Module landing rocket. The coupons were also pitted by the impact of larger soil particles with an average of 103 pits/cm 2. The average entry size of the pits was 83.7 μm (major diameter) × 74.5 μm (minor diameter) and the average estimated penetration depth was 88.4 μm. Pitting in the surface of the coupons correlates to removal of lunar fines and is likely a signature of lunar material imparting localized momentum/energy sufficient to cause cracking of the paint. Comparison with the lunar soil particle size distribution and the optical density of blowing soil during lunar landings indicates that the Surveyor III spacecraft was not exposed to the direct spray of the landing Lunar Module, but instead experienced only the fringes of the spray of soil. Had Surveyor III been exposed to the direct spray, the damage would have been orders of magnitude higher.
Pitted Landforms in Southern Hellas Planitia
2015-03-25
This image is of a portion of the Southern plains region within Hellas, the largest impact basin on Mars, with a diameter of about 2300 kilometers 1400 miles, as observed by NASA Mars Reconnaissance Orbiter. There are three main phenomena apparent in this image. First, the faint dark streaks that criss-cross the terrain are dust devil tracks that clear the bright dust along their way. Second, the subtle overall bumpy "basketball" texture of the surface is formed by repeated seasonal freezing and thawing of the ice-rich regolith and is common at higher latitudes. Third, the large, elliptical, scalloped depressions are common in permafrost terrains in both hemispheres, where thick, latitude-dependent sedimentary mantles comprise the surface units. These mantles are composed of ice-rich sediments that degrade as the ice sublimates away and is heated either by the Sun or by locally higher geothermal gradients. Sublimation, or the direct change in phase from ice to gas, occurs on Mars because of its low density atmosphere. These depressions have steeper pole-facing slopes, whereas the equator-facing slopes gently fade into the surrounding terrain. At full resolution (see close up view), numerous sublimation pits and networks of polygonal cracks are visible on the steeper, unstable pole-ward facing slopes. The overall morphology of this terrain is characteristic of what is called "thermokarstic degradation processes," which is a term used to describe the formation of pits in an ice-rich terrain due to loss of ice creating pits and collapse features. http://photojournal.jpl.nasa.gov/catalog/PIA19350
Guziewicz, Karina E.; Iwabe, Simone; Swider, Malgorzata; Scott, Erin M.; Savina, Svetlana V.; Ruthel, Gordon; Stefano, Frank; Zhang, Lingli; Zorger, Richard; Sumaroka, Alexander; Jacobson, Samuel G.; Aguirre, Gustavo D.
2014-01-01
Retinal areas of specialization confer vertebrates with the ability to scrutinize corresponding regions of their visual field with greater resolution. A highly specialized area found in haplorhine primates (including humans) is the fovea centralis which is defined by a high density of cone photoreceptors connected individually to interneurons, and retinal ganglion cells (RGCs) that are offset to form a pit lacking retinal capillaries and inner retinal neurons at its center. In dogs, a local increase in RGC density is found in a topographically comparable retinal area defined as the area centralis. While the canine retina is devoid of a foveal pit, no detailed examination of the photoreceptors within the area centralis has been reported. Using both in vivo and ex vivo imaging, we identified a retinal region with a primate fovea-like cone photoreceptor density but without the excavation of the inner retina. Similar anatomical structure observed in rare human subjects has been named fovea-plana. In addition, dogs with mutations in two different genes, that cause macular degeneration in humans, developed earliest disease at the newly-identified canine fovea-like area. Our results challenge the dogma that within the phylogenetic tree of mammals, haplorhine primates with a fovea are the sole lineage in which the retina has a central bouquet of cones. Furthermore, a predilection for naturally-occurring retinal degenerations to alter this cone-enriched area fills the void for a clinically-relevant animal model of human macular degenerations. PMID:24599007
NASA Astrophysics Data System (ADS)
Smagina, Zh. V.; Zinovyev, V. A.; Rudin, S. A.; Novikov, P. L.; Rodyakina, E. E.; Dvurechenskii, A. V.
2018-04-01
Regular pit-patterned Si(001) substrates were prepared by electron-beam lithography followed by plasma chemical etching. The geometry of the pits was controlled by varying the etching conditions and the electron-beam exposure duration. It was shown that the location of three-dimensional (3D) Ge nanoislands subsequently grown on the pit-patterned Si substrates depends on the shape of the pit bottom. In the case of pits having a sharp bottom, 3D Ge islands nucleate inside the pits. For pits with a wide flat bottom, the 3D Ge island nucleation takes place at the pit periphery. This effect is attributed to the strain relaxation depending not only on the initial pit shape, but also on its evolution during the Ge wetting layer deposition. It was shown by Monte Carlo simulations that in the case of a pit with a pointed bottom, the relaxation is most effective inside the pit, while for a pit with a wide bottom, the most relaxed area migrates during Ge deposition from the pit bottom to its edges, where 3D Ge islands nucleate.
The effects of intragrain defects on the local photoresponse of polycrystalline silicon solar cells
NASA Astrophysics Data System (ADS)
Inoue, N.; Wilmsen, C. W.; Jones, K. A.
1981-02-01
Intragrain defects in Wacker cast and Monsanto zone-refined polycrystalline silicon materials were investigated using the electron-beam-induced current (EBIC) technique. The EBIC response maps were compared with etch pit, local diffusion length and local photoresponse measurements. It was determined that the Wacker polycrystalline silicon has a much lower density of defects than does the Monsanto polycrystalline silicon and that most of the defects in the Wacker material are not active recombination sites. A correlation was found between the recombination site density, as determined by EBIC, and the local diffusion length. It is shown that a large density of intragrain recombination sites greatly reduces the minority carrier diffusion length and thus can significantly reduce the photoresponse of solar cells.
NASA Technical Reports Server (NTRS)
Hillman, E.; Barlow, N. G.
2005-01-01
Impact craters containing central pits are rare on the terrestrial planets but common on icy bodies. Mars is the exception among the terrestrial planets, where central pits are seen on crater floors ( floor pits ) as well as on top of central peaks ( summit pits ). Wood et al. [1] proposed that degassing of subsurface volatiles during crater formation produced central pits. Croft [2] argued instead that central pits might form during the impact of volatile-rich comets. Although central pits are seen in impact craters on icy moons such as Ganymede, they do show some significant differences from their martian counterparts: (a) only floor pits are seen on Ganymede, and (b) central pits begin to occur at crater diameters where the peak ring interior morphology begins to appear in terrestrial planet craters [3]. A study of craters containing central pits was conducted by Barlow and Bradley [4] using Viking imagery. They found that 28% of craters displaying an interior morphology on Mars contain central pits. Diameters of craters containing central pits ranged from 16 to 64 km. Barlow and Bradley noted that summit pit craters tended to be smaller than craters containing floor pits. They also noted a correlation of central pit craters with the proposed rings of large impact basins. They argued that basin ring formation fractured the martian crust and allowed subsurface volatiles to concentrate in these locations. They favored the model that degassing of the substrate during crater formation was responsible for central pit formation due to the preferential location of central pit craters along these basin rings.
How Well do we Know Near-Surface Density When Determining Mass Balance by the Geodetic Method?
NASA Astrophysics Data System (ADS)
Kuhn, M. H.; Matzi, E.
2005-12-01
From a data set of firn pits in the accumulation area of Hintereisferner in the years 1964 - 2002 the behavior of density and water equivalent was analyzed with a view to estimating the potential errors in the application of the geodetic method. Since annual specific balance ranged from 100 to 3300 mm w.e. the profiles were scaled to total depth. For the uppermost 10% of the annual deposit at a typical location the 1964-2002 mean density would be 350 kg/m-3 with a standard deviation of 110 kg/m-3; for the 10% layer at the base of the annual snowpack the respective figures are 510 +- 30 kg/m-3. The normalized long term means of an ensemble of 9 pits ranged from 310 to 380 kg/m-3 in the top layer and from 510 to 540 kg/m-3 in the bottom layer. When one outlier is removed the the range in the bottom layer reduces to 525 to 540 kg/m-3. This small local variance encourages the use of the geodetic method. The comparison of elevation models of 1969 and 1997 yields a mass change that agrees very well with the results of the glaciological method provided the volume change is converted to mass with a density of 900 kg/m-3. While this may be true for the entire glacier on long terms, it will fail for individual years in the accumulation area. Possible errors are calculated from the data set emphasizing the role of year to year changes of specific balance and accumulation area ratio.
Progress in Electron Beam Mastering of 100 Gbit/inch2 Density Disc
NASA Astrophysics Data System (ADS)
Takeda, Minoru; Furuki, Motohiro; Yamamoto, Masanobu; Shinoda, Masataka; Saito, Kimihiro; Aki, Yuichi; Kawase, Hiroshi; Koizumi, Mitsuru; Miyokawa, Toshiaki; Mutou, Masao; Handa, Nobuo
2004-07-01
We developed an electron beam recorder (EBR) capable of recording master discs under atmospheric conditions using a novel differential pumping head. Using the EBR and optimized fabrication process for Si-etched discs with reactive ion etching (RIE), a bottom signal jitter of 9.6% was obtained from a 36 Gbit/inch2 density disc, readout using a near-field optical pickup with an effective numerical aperture (NA) of 1.85 and a wavelength of 405 nm. We also obtained the eye patterns from a 70 Gbit/inch2 density disc readout using an optical pickup with a 2.05 NA and the same wavelength, and showed almost the same modulation ratio as the simulation value. Moreover, the capability of producing pit patterns corresponding to a 104 Gbit/inch2 density is demonstrated.
Long Duration Exposure Facility (LDEF) attitude measurements of the interplanetary dust experiment
NASA Technical Reports Server (NTRS)
Kassel, Philip C., Jr.; Singer, S. Fred; Mulholland, J. Derral; Oliver, John P.; Weinberg, Jerry L.; Cooke, William J.; Wortman, Jim J.; Motley, William R., III
1992-01-01
The Long Duration Exposure Facility (LDEF) Interplanetary Dust Experiment (IDE) was unique in providing a time history of impacts of micron-sized particles on six orthogonal faces of LDEF during the first year in orbit. The value of this time resolved data depended on and was enhanced by the proper operation of some basic LDEF systems. Thus, the value of the data is greatly enhanced when the location and orientation of LDEF is known for each time of impact. The location and velocity of LDEF as a function of time can be calculated from the 'two-line elements' published by GSFC during the first year of the LDEF mission. The attitude of LDEF was passively stabilized in a gravity-gradient mode and a magnetically anchored viscous damper was used to dissipate roll, pitch, and yaw motions. Finally, the IDE used a standard LDEF Experiment Power and Data System (EPDS) to collect and store data and also to provide a crystal derived clock pulse (1 count every 13.1072 seconds) for all IDE time measurements. All that remained for the IDE was to provide a system to calibrate the clock, eliminating accumulative errors, and also verify the attitude of LDEF. The IDE used solar cells on six orthogonal faces to observe the LDEF sunrise and provide data about the LDEF attitude. The data was recorded by the EPDS about 10 times per day for the first 345 days of the LDEF mission. This data consist of the number of IDE counts since the last LDEF sunrise and the status of the six solar cells (light or dark) at the time of the last IDE count. The EPDS determined the time that data was recorded and includes, with each record, the master EPDS clock counter (1 count every 1.6384 seconds) that provided the range and resolution for time measurements. The IDE solar cells provided data for an excellent clock calibration, meeting their primary purpose, and the time resolved LDEF attitude measurements that can be gleaned from this data are presented.
Putnam, Karen T; Wilcox, Marsha; Robertson-Blackmore, Emma; Sharkey, Katherine; Bergink, Veerle; Munk-Olsen, Trine; Deligiannidis, Kristina M; Payne, Jennifer; Altemus, Margaret; Newport, Jeffrey; Apter, Gisele; Devouche, Emmanuel; Viktorin, Alexander; Magnusson, Patrik; Penninx, Brenda; Buist, Anne; Bilszta, Justin; O'Hara, Michael; Stuart, Scott; Brock, Rebecca; Roza, Sabine; Tiemeier, Henning; Guille, Constance; Epperson, C Neill; Kim, Deborah; Schmidt, Peter; Martinez, Pedro; Di Florio, Arianna; Wisner, Katherine L; Stowe, Zachary; Jones, Ian; Sullivan, Patrick F; Rubinow, David; Wildenhaus, Kevin; Meltzer-Brody, Samantha
2017-06-01
The perinatal period is a time of high risk for onset of depressive disorders and is associated with substantial morbidity and mortality, including maternal suicide. Perinatal depression comprises a heterogeneous group of clinical subtypes, and further refinement is needed to improve treatment outcomes. We sought to empirically identify and describe clinically relevant phenotypic subtypes of perinatal depression, and further characterise subtypes by time of symptom onset within pregnancy and three post-partum periods. Data were assembled from a subset of seven of 19 international sites in the Postpartum Depression: Action Towards Causes and Treatment (PACT) Consortium. In this analysis, the cohort was restricted to women aged 19-40 years with information about onset of depressive symptoms in the perinatal period and complete prospective data for the ten-item Edinburgh postnatal depression scale (EPDS). Principal components and common factor analysis were used to identify symptom dimensions in the EPDS. The National Institute of Mental Health research domain criteria functional constructs of negative valence and arousal were applied to the EPDS dimensions that reflect states of depressed mood, anhedonia, and anxiety. We used k-means clustering to identify subtypes of women sharing symptom patterns. Univariate and bivariate statistics were used to describe the subtypes. Data for 663 women were included in these analyses. We found evidence for three underlying dimensions measured by the EPDS: depressed mood, anxiety, and anhedonia. On the basis of these dimensions, we identified five distinct subtypes of perinatal depression: severe anxious depression, moderate anxious depression, anxious anhedonia, pure anhedonia, and resolved depression. These subtypes have clear differences in symptom quality and time of onset. Anxiety and anhedonia emerged as prominent symptom dimensions with post-partum onset and were notably severe. Our findings show that there might be different types and severity of perinatal depression with varying time of onset throughout pregnancy and post partum. These findings support the need for tailored treatments that improve outcomes for women with perinatal depression. Janssen Research & Development. Copyright © 2017 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cook, Caitlyn Christian
An evaporation barrier is required to enhance the lifetime of electrophoretic deposition (EPD) displays. As EPD functions on the basis of reversible deposition and resuspension of colloids suspended in a solvent, evaporation of the solvent ultimately leads to device failure. Incorporation of a thiol-polybutadiene elastomer into EPD displays enabled display lifetime surpassing six months in counting and catalyzed rigid display transition into a flexible package. Final flexible display transition to mass production compels an electronic-ink approach to encapsulate display suspension within an elastomer shell. Final thiol-polybutadiene photosensitive resin network microstructure was idealized to be dense, homogeneous, and expose an elasticmore » response to deformation. Research at hand details an approach to understanding microstructural change within display elastomers. Polybutadiene-based resin properties are modified via polymer chain structure, with and without added aromatic urethane methacrylate difunctionality, and in measuring network response to variation in thiol and initiator concentration. Dynamic mechanical analysis results signify that cross-linked segments within a difunctionalized polybutadiene network were on average eight times more elastically active than that of linked segments within a non-functionalized polybutadiene network. Difunctionalized polybutadiene samples also showed a 2.5 times greater maximum elastic modulus than non-functionalized samples. Hybrid polymer composed of both polybutadiene chains encompassed TE-2000 stiffness and B-1000 elasticity for use in encapsulating display suspension. Later experiments measured kinetic and rheological response due to alteration in dithiol cross-linker chain length via real time Fourier transform infrared spectroscopy and real-time dynamic rheology. Distinct differences were discovered between dithiol resin systems, as maximum thiol conversion achieved in short and long chain length dithiols was 86% and 11%, respectively. Oscillatory real-time rheological experiments confirmed a more uniform network to better dissipate applied shear in short chain length dithiol systems, as long chain length dithiols relayed a steep internal stress build-up due to less cross-links and chain entanglements. Thorough understanding of network formation aids the production of a stronger and impermeable elastomeric barrier for preservation of EPD displays.« less
Green, Eric P; Tuli, Hawa; Kwobah, Edith; Menya, D; Chesire, Irene; Schmidt, Christina
2018-03-01
Routine screening for perinatal depression is not common in most primary health care settings. The U.S. Preventive Services Task Force only recently updated their recommendation on depression screening to specifically recommend screening during the pre- and postpartum periods. While practitioners in high-income countries can respond to this new recommendation by implementing one of several existing depression screening tools developed in Western contexts, such as the Edinburgh Postnatal Depression Scale (EPDS) or the Patient Health Questionnaire-9 (PHQ-9), these tools lack strong evidence of cross-cultural equivalence, validity for case finding, and precision in measuring response to treatment in developing countries. Thus, there is a critical need to develop and validate new screening tools for perinatal depression that can be used by lay health workers, primary health care personnel, and patients. Working in rural Kenya, we used free listing, card sorting, and item analysis methods to develop a locally-relevant screening tool that blended Western psychiatric concepts with local idioms of distress. We conducted a validation study with a random sample of 193 pregnant women and new mothers to test the diagnostic accuracy of this scale along with the EPDS and PHQ-9. The sensitivity/specificity of the EPDS and PHQ-9 was estimated to be 0.70/0.72 and 0.70/0.73, respectively. This compared to sensitivity/specificity of 0.90/0.90 for a new 9-item locally-developed tool called the Perinatal Depression Screening (PDEPS). Across these three tools, internal consistency reliability ranged from 0.77 to 0.81 and test-retest reliability ranged from 0.57 to 0.67. The prevalence of depression ranges from 5.2% to 6.2% depending on the clinical reference standard. The EPDS and PHQ-9 are valid and reliable screening tools for perinatal depression in rural Western Kenya, the PDEPS may be a more useful alternative. At less than 10%, the prevalence of depression in this region appears to be lower than other published estimates for African and other low-income countries. Copyright © 2017 Elsevier B.V. All rights reserved.
Maternal depression and child development: Evidence from São Paulo's Western Region Cohort Study.
Brentani, Alexandra; Fink, Günther
2016-09-01
While a growing body of evidence has investigated the relationship between maternal mental health and child development, evidence on children's early life outcomes remains mixed. We analyze the empirical relationship between maternal depression and children's development at age one using data from the São Paulo Western Region Cohort project. Seven hundred and ninety-eight (798) mother-child dyads living in the Butantã-Jaguaré' region of São Paulo were assessed through a home visit between January and March 2015. Maternal mental health was assessed using the Edinburgh Postnatal Depression Scale (EPDS). Mothers were classified as "possibly depressed" if their EPDS score was between 10 and 13 and as "likely depressed" if their EPDS score was > 13. The child outcomes analyzed were height, weight, and overall development as assessed by the Ages and Stages Questionnaire (ASQ). Height and weight were age-normalized using WHO growth standards. Stunting was defined as height-for-age z-score (HAZ) < -2. Obesity was defined as body mass index z-score (BMIZ) > 2. Adjusted and unadjusted linear regression models were used to assess the associations between Edinburgh scores and child outcomes. No association was found between maternal depression variables and children's height, weight, stunting, and obesity. Positive associations were found between possible depression and ASQ (delta = 0.33; 95CI 0.11-0.54; p-value<0.01); no associations were found between likely depression and any of the outcomes analyzed. The results from this study suggest that symptoms of maternal depression are not associated with delays in child development in the study setting analyzed. Further research will be needed to understand this lack of association: while it is possible that caregivers' mental health did not affect caregiving behavior, it is possible that the effect of maternal depression can vary according to timing, persistence, and intensity. It is also possible that the EPDS instrument may fail to identify mothers with clinical depression, or that children with depressed mothers get increased support from other family members or public early childhood focused programs.
Meltzer-Brody, Samantha; Stuebe, Alison; Dole, Nancy; Savitz, David; Rubinow, David; Thorp, John
2011-01-01
Perinatal depression has a prevalence of 10% with devastating consequences for mother and baby. The prospective identification of those at risk for postpartum (PPD) or prenatal (PND) depression has led to biomarker searches in pregnancy. There are conflicting reports of associations between midpregnancy placental CRH (pCRH) and PPD or PND. The objective of the study was to quantify the association of maternal pCRH with PPD and PND. This was a prospective cohort study (the Pregnancy, Infection, and Nutrition Study). The study was conducted at a prenatal clinics at the University of North Carolina at Chapel Hill. Patients included 1230 pregnant women. The relationship between pCRH at less than 20 wk and 24-29 wk and maternal depression assessed in pregnancy [Center for Epidemiologic Studies Depression Scale (CES-D)] and postpartum (12 wk and 1 yr) with the Edinburgh Postnatal Depression Scale (EPDS). At 24-29 wk, 24.8% of women had CES-D score of 17 or greater, and 9.7% had a CES-D score of 25 or greater. At 12 wk postpartum, 18.2% of women had an EPDS score of 10 or greater and 7.6% had an EPDS score of 13 or greater. CRH measures at less than 20 wk and 24-29 wk were inversely correlated with a CES-D score at 24-29 wk (n = 1080, P < 0.05 and P < 0.01, respectively). Pregnancy pCRH was not correlated with the EPDS score at 12 wk (n = 484) or 1 yr postpartum (n = 391). In covariate-adjusted models, higher pCRH was not associated with a CES-D of 17 or greater at 24-29 wk (odds ratio 0.88 per sd change in pCRH at 24-29 wk, 95% confidence interval 0.76-1.03). There was no association between log CRH at 24-29 wk and PPD (covariate-adjusted odds ratio per sd 0.99, 95% confidence interval 0.69-1.42). Higher midpregnancy pCRH was not associated with an increased risk of PND or PPD.
DOE Office of Scientific and Technical Information (OSTI.GOV)
D'Ercole, Loredana, E-mail: l.dercole@smatteo.pv.it; Quaretti, Pietro; Cionfoli, Nicola
2013-04-15
To measure the maximum entrance skin dose (MESD) on patients undergoing carotid artery stenting (CAS) using embolic-protection devices, to analyze the dependence of dose and exposure parameters on anatomical, clinical, and technical factors affecting the procedure complexity, to obtain some local diagnostic reference levels (DRLs), and to evaluate whether overcoming DRLs is related to procedure complexity. MESD were evaluated with radiochromic films in 31 patients (mean age 72 {+-} 7 years). Five of 33 (15 %) procedures used proximal EPD, and 28 of 33 (85 %) procedures used distal EPD. Local DRLs were derived from the recorded exposure parameters inmore » 93 patients (65 men and 28 women, mean age 73 {+-} 9 years) undergoing 96 CAS with proximal (33 %) or distal (67 %) EPD. Four bilateral lesions were included. MESD values (mean 0.96 {+-} 0.42 Gy) were <2 Gy without relevant dependence on procedure complexity. Local DRL values for kerma area product (KAP), fluoroscopy time (FT), and number of frames (N{sub FR}) were 269 Gy cm{sup 2}, 28 minutes, and 251, respectively. Only simultaneous bilateral treatment was associated with KAP (odds ratio [OR] 10.14, 95 % confidence interval [CI] 1-102.7, p < 0.05) and N{sub FR} overexposures (OR 10.8, 95 % CI 1.1-109.5, p < 0.05). Type I aortic arch decreased the risk of FT overexposure (OR 0.4, 95 % CI 0.1-0.9, p = 0.042), and stenosis {>=} 90 % increased the risk of N{sub FR} overexposure (OR 2.8, 95 % CI 1.1-7.4, p = 0.040). At multivariable analysis, stenosis {>=} 90 % (OR 2.8, 95 % CI 1.1-7.4, p = 0.040) and bilateral treatment (OR 10.8, 95 % CI 1.1-109.5, p = 0.027) were associated with overexposure for two or more parameters. Skin doses are not problematic in CAS with EPD because these procedures rarely lead to doses >2 Gy.« less
Putnam, Karen T; Wilcox, Marsha; Robertson-Blackmore, Emma; Sharkey, Katherine; Bergink, Veerle; Munk-Olsen, Trine; Deligiannidis, Kristina M; Payne, Jennifer; Altemus, Margaret; Newport, Jeffrey; Apter, Gisele; Devouche, Emmanuel; Viktorin, Alexander; Magnusson, Patrik; Penninx, Brenda; Buist, Anne; Bilszta, Justin; O’Hara, Michael; Stuart, Scott; Brock, Rebecca; Roza, Sabine; Tiemeier, Henning; Guille, Constance; Epperson, C Neill; Kim, Deborah; Schmidt, Peter; Martinez, Pedro; Di Florio, Arianna; Wisner, Katherine L; Stowe, Zachary; Jones, Ian; Sullivan, Patrick F; Rubinow, David; Wildenhaus, Kevin; Meltzer-Brody, Samantha
2018-01-01
Summary Background The perinatal period is a time of high risk for onset of depressive disorders and is associated with substantial morbidity and mortality, including maternal suicide. Perinatal depression comprises a heterogeneous group of clinical subtypes, and further refinement is needed to improve treatment outcomes. We sought to empirically identify and describe clinically relevant phenotypic subtypes of perinatal depression, and further characterise subtypes by time of symptom onset within pregnancy and three post-partum periods. Methods Data were assembled from a subset of seven of 19 international sites in the Postpartum Depression: Action Towards Causes and Treatment (PACT) Consortium. In this analysis, the cohort was restricted to women aged 19–40 years with information about onset of depressive symptoms in the perinatal period and complete prospective data for the ten-item Edinburgh postnatal depression scale (EPDS). Principal components and common factor analysis were used to identify symptom dimensions in the EPDS. The National Institute of Mental Health research domain criteria functional constructs of negative valence and arousal were applied to the EPDS dimensions that reflect states of depressed mood, anhedonia, and anxiety. We used k-means clustering to identify subtypes of women sharing symptom patterns. Univariate and bivariate statistics were used to describe the subtypes. Findings Data for 663 women were included in these analyses. We found evidence for three underlying dimensions measured by the EPDS: depressed mood, anxiety, and anhedonia. On the basis of these dimensions, we identified five distinct subtypes of perinatal depression: severe anxious depression, moderate anxious depression, anxious anhedonia, pure anhedonia, and resolved depression. These subtypes have clear differences in symptom quality and time of onset. Anxiety and anhedonia emerged as prominent symptom dimensions with post-partum onset and were notably severe. Interpretation Our findings show that there might be different types and severity of perinatal depression with varying time of onset throughout pregnancy and post partum. These findings support the need for tailored treatments that improve outcomes for women with perinatal depression. Funding Janssen Research & Development. PMID:28476427
3D Modeling of Landslide in Open-pit Mining on Basis of Ground-based LIDAR Data
NASA Astrophysics Data System (ADS)
Hu, H.; Fernandez-Steeger, T. M.; Azzam, R.; Arnhardt, C.
2009-04-01
Slope stability is not only an important problem which is related to production and safety in open-pit mining, but also very complex task. There are three main reasons which affect the slope stability as follows: geotechnical factors: Geological structure, lithologic characteristics, water, cohesion, friction, etc.; climate factors: Rainfall and temperature; and external factors: Open-pit mining process, explosion vibration, dynamic load, etc.. The 3rd reason, as a specially one in open-pit mining, not only causes some dynamic problems but also induces the fast geometry changing which must be considered in the following research using numerical simulation and stability analysis. Recently, LIDAR technology has been applied in many fields and places in the world wide. Ground-based LIDAR technology with high accuracy up to 3mm increasingly accommodates to monitoring landslides and detecting changing. LIDAR data collection and preprocessing research have been carried out by Department of Engineering Geology and Hydrogeology at RWTH Aachen University. LIDAR data, so-called a point-cloud of mass data in high density can be obtained in short time for the sensitive open-pit mining area by using ground-based LIDAR. To obtain a consistent surface model, it is necessary to set up multiple scans with the ground-based LIDAR. The framework of data preprocessing which can be implemented by Poly-Works is introduced as follows: gross error detection and elimination, integration of reference frame, model fusion of different scans (re-sampled in overlap region), data reduction without removing the useful information which is a challenge and research front in LIDAR data processing. After data preprocessing, 3D surface model can be directly generated in Poly-Works or generated in other software by building the triangular meshes. The 3D surface landslide model can be applied to further researches such as: real time landslide geometry monitoring due to the fast data collection and processing; change detecting by means of overlying different periods of topographic or geometric data; FEM (Finite Element Method) numerical simulation on basis of combining with the geotechnical properties and parameters to analyze slope stability and predict future movements for designing and rectifying the open-pit mining process; using the reverse engineering thought for developing constitutive models. An improved 3D surface model (HRDEM) which is based on fast data collection and precise data processing on basis of ground-based LIDAR technology is important contribution for further researches of slope stability in open-pit mining area.
NASA Astrophysics Data System (ADS)
Michikami, T.; Hagermann, A.; Miyamoto, H.; Miura, S.; Haruyama, J.; Lykawka, P. S.
2014-06-01
High-resolution images reveal that numerous pit craters exist on the surface of Mars. For some pit craters, the depth-to-diameter ratios are much greater than for ordinary craters. Such deep pit craters are generally considered to be the results of material drainage into a subsurface void space, which might be formed by a lava tube, dike injection, extensional fracturing, and dilational normal faulting. Morphological studies indicate that the formation of a pit crater might be triggered by the impact event, and followed by collapse of the ceiling. To test this hypothesis, we carried out laboratory experiments of impact cratering into brittle targets with variable roof thickness. In particular, the effect of the target thickness on the crater formation is studied to understand the penetration process by an impact. For this purpose, we produced mortar targets with roof thickness of 1-6 cm, and a bulk density of 1550 kg/m3 by using a mixture of cement, water and sand (0.2 mm) in the ratio of 1:1:10, by weight. The compressive strength of the resulting targets is 3.2±0.9 MPa. A spherical nylon projectile (diameter 7 mm) is shot perpendicularly into the target surface at the nominal velocity of 1.2 km/s, using a two-stage light-gas gun. Craters are formed on the opposite side of the impact even when no target penetration occurs. Penetration of the target is achieved when craters on the opposite sides of the target connect with each other. In this case, the cross section of crater somehow attains a flat hourglass-like shape. We also find that the crater diameter on the opposite side is larger than that on the impact side, and more fragments are ejected from the crater on the opposite side than from the crater on the impact side. This result gives a qualitative explanation for the observation that the Martian deep pit craters lack a raised rim and have the ejecta deposit on their floor instead. Craters are formed on the opposite impact side even when no penetration occurs. Penetration is achieved when craters of both sides are connected. Crater diameter on the opposite side is larger than that on the impact side. More fragments are ejected from the opposite side than from the impact side. We present a qualitative explanation for the shapes of Martian deep pit craters.
Mutuku, Francis M; Bayoh, M Nabie; Gimnig, John E; Vulule, John M; Kamau, Luna; Walker, Edward D; Kabiru, Ephantus; Hawley, William A
2006-01-01
The productivity of larval habitats of the malaria vector Anopheles gambiae for pupae (the stage preceding adult metamorphosis) is poorly known, yet adult emergence from habitats is the primary determinant of vector density. To assess it, we used absolute sampling methods in four studies involving daily sampling for 25 days in 6 habitat types in a village in western Kenya. Anopheles gambiae s.s. comprised 82.5% of emergent adults and Anopheles arabiensis the remainder. Pupal production occurred from a subset of habitats, primarily soil burrow pits, and was discontinuous in time, even when larvae occupied all habitats continuously. Habitat stability was positively associated with pupal productivity. In a dry season, pupal productivity was distributed between burrow pits and pools in streambeds. Overall, these data support the notion that source reduction measures against recognizably productive habitats would be a useful component of an integrated management program for An. gambiae in villages.
2011-01-01
Background The inorganic (Pi) phosphate transporter (PiT) family comprises known and putative Na+- or H+-dependent Pi-transporting proteins with representatives from all kingdoms. The mammalian members are placed in the outer cell membranes and suggested to supply cells with Pi to maintain house-keeping functions. Alignment of protein sequences representing PiT family members from all kingdoms reveals the presence of conserved amino acids and that bacterial phosphate permeases and putative phosphate permeases from archaea lack substantial parts of the protein sequence when compared to the mammalian PiT family members. Besides being Na+-dependent Pi (NaPi) transporters, the mammalian PiT paralogs, PiT1 and PiT2, also are receptors for gamma-retroviruses. We have here exploited the dual-function of PiT1 and PiT2 to study the structure-function relationship of PiT proteins. Results We show that the human PiT2 histidine, H502, and the human PiT1 glutamate, E70, - both conserved in eukaryotic PiT family members - are critical for Pi transport function. Noticeably, human PiT2 H502 is located in the C-terminal PiT family signature sequence, and human PiT1 E70 is located in ProDom domains characteristic for all PiT family members. A human PiT2 truncation mutant, which consists of the predicted 10 transmembrane (TM) domain backbone without a large intracellular domain (human PiT2ΔR254-V483), was found to be a fully functional Pi transporter. Further truncation of the human PiT2 protein by additional removal of two predicted TM domains together with the large intracellular domain created a mutant that resembles a bacterial phosphate permease and an archaeal putative phosphate permease. This human PiT2 truncation mutant (human PiT2ΔL183-V483) did also support Pi transport albeit at very low levels. Conclusions The results suggest that the overall structure of the Pi-transporting unit of the PiT family proteins has remained unchanged during evolution. Moreover, in combination, our studies of the gene structure of the human PiT1 and PiT2 genes (SLC20A1 and SLC20A2, respectively) and alignment of protein sequences of PiT family members from all kingdoms, along with the studies of the dual functions of the human PiT paralogs show that these proteins are excellent as models for studying the evolution of a protein's structure-function relationship. PMID:21586110
Bøttger, Pernille; Pedersen, Lene
2011-05-17
The inorganic (Pi) phosphate transporter (PiT) family comprises known and putative Na(+)- or H(+)-dependent Pi-transporting proteins with representatives from all kingdoms. The mammalian members are placed in the outer cell membranes and suggested to supply cells with Pi to maintain house-keeping functions. Alignment of protein sequences representing PiT family members from all kingdoms reveals the presence of conserved amino acids and that bacterial phosphate permeases and putative phosphate permeases from archaea lack substantial parts of the protein sequence when compared to the mammalian PiT family members. Besides being Na(+)-dependent P(i) (NaP(i)) transporters, the mammalian PiT paralogs, PiT1 and PiT2, also are receptors for gamma-retroviruses. We have here exploited the dual-function of PiT1 and PiT2 to study the structure-function relationship of PiT proteins. We show that the human PiT2 histidine, H(502), and the human PiT1 glutamate, E(70),--both conserved in eukaryotic PiT family members--are critical for P(i) transport function. Noticeably, human PiT2 H(502) is located in the C-terminal PiT family signature sequence, and human PiT1 E(70) is located in ProDom domains characteristic for all PiT family members.A human PiT2 truncation mutant, which consists of the predicted 10 transmembrane (TM) domain backbone without a large intracellular domain (human PiT2ΔR(254)-V(483)), was found to be a fully functional P(i) transporter. Further truncation of the human PiT2 protein by additional removal of two predicted TM domains together with the large intracellular domain created a mutant that resembles a bacterial phosphate permease and an archaeal putative phosphate permease. This human PiT2 truncation mutant (human PiT2ΔL(183)-V(483)) did also support P(i) transport albeit at very low levels. The results suggest that the overall structure of the P(i)-transporting unit of the PiT family proteins has remained unchanged during evolution. Moreover, in combination, our studies of the gene structure of the human PiT1 and PiT2 genes (SLC20A1 and SLC20A2, respectively) and alignment of protein sequences of PiT family members from all kingdoms, along with the studies of the dual functions of the human PiT paralogs show that these proteins are excellent as models for studying the evolution of a protein's structure-function relationship. © 2011 Bøttger and Pedersen; licensee BioMed Central Ltd.
The three principles of action: a Pavlovian-instrumental transfer hypothesis
Cartoni, Emilio; Puglisi-Allegra, Stefano; Baldassarre, Gianluca
2013-01-01
Pavlovian conditioned stimuli can influence instrumental responding, an effect called Pavlovian-instrumental transfer (PIT). During the last decade, PIT has been subdivided into two types: specific PIT and general PIT, each having its own neural substrates. Specific PIT happens when a conditioned stimulus (CS) associated with a reward enhances an instrumental response directed to the same reward. Under general PIT, instead, the CS enhances a response directed to a different reward. While important progress has been made into identifying the neural substrates, the function of specific and general PIT and how they interact with instrumental responses are still not clear. In the experimental paradigm that distinguishes specific and general PIT an effect of PIT inhibition has also been observed and is waiting for an explanation. Here we propose an hypothesis that links these three PIT effects (specific PIT, general PIT and PIT inhibition) to three aspects of action evaluation. These three aspects, which we call “principles of action”, are: context, efficacy, and utility. In goal-directed behavior, an agent has to evaluate if the context is suitable to accomplish the goal, the efficacy of his action in getting the goal, and the utility of the goal itself: we suggest that each of the three PIT effects is related to one of these aspects of action evaluation. In particular, we link specific PIT with the estimation of efficacy, general PIT with the evaluation of utility, and PIT inhibition with the adequacy of context. We also provide a latent cause Bayesian computational model that exemplifies this hypothesis. This hypothesis and the model provide a new framework and new predictions to advance knowledge about PIT functioning and its role in animal adaptation. PMID:24312025
NASA Astrophysics Data System (ADS)
Lei, Yaguo; Liu, Zongyao; Wang, Delong; Yang, Xiao; Liu, Huan; Lin, Jing
2018-06-01
Tooth damage often causes a reduction in gear mesh stiffness. Thus time-varying mesh stiffness (TVMS) can be treated as an indication of gear health conditions. This study is devoted to investigating the mesh stiffness variations of a pair of external spur gears with tooth pitting, and proposes a new model for describing tooth pitting based on probability distribution. In the model, considering the appearance and development process of tooth pitting, we model the pitting on the surface of spur gear teeth as a series of pits with a uniform distribution in the direction of tooth width and a normal distribution in the direction of tooth height, respectively. In addition, four pitting degrees, from no pitting to severe pitting, are modeled. Finally, influences of tooth pitting on TVMS are analyzed in details and the proposed model is validated by comparing with a finite element model. The comparison results show that the proposed model is effective for the TVMS evaluations of pitting gears.
Evaluation of the 3-GeV proton beam profile at the spallation target of the JSNS
NASA Astrophysics Data System (ADS)
Meigo, Shin-ichiro; Noda, Fumiaki; Ishikura, Syuichi; Futakawa, Masatoshi; Sakamoto, Shinichi; Ikeda, Yujiro
2006-06-01
At JSNS, 3-GeV protons beam is delivered from rapid cycling synchrotron (RCS) to the spallation neutron target. In order to reduce the damage of pitting on the target container, the peak current density should be kept as small as possible. In this study, the beam profile at spallation neutron target is evaluated. The phase-space distribution, including the space-charge effect, is calculated with SIMPSONS code. The beam profile on the target is obtained with the transfer matrix from exit of RCS to the target. As for injection to RCS, two methods of correlated and anti-correlated painting are considered. By using anti-correlated painting for injection of beam at RCS, it is found the shape of beam becomes flatter than the distribution by using correlated painting. As other aspect for the study of target, in order to carry out target performance test especially for the study of pitting issue, it is better to have the beam profile variety from the beginning of facility. The adjustable range for the beam profile at the beginning is also studied. Although the beam shape is narrow and the duty is very low, the strong enough peak density is achievable equivalent as 1 MW.
Energetic particles at venus: galileo results.
Williams, D J; McEntire, R W; Krimigis, S M; Roelof, E C; Jaskulek, S; Tossman, B; Wilken, B; Stüdemann, W; Armstrong, T P; Fritz, T A; Lanzerotti, L J; Roederer, J G
1991-09-27
At Venus the Energetic Particles Detector (EPD) on the Galileo spacecraft measured the differential energy spectra and angular distributions of ions >22 kiloelectron volts (keV) and electrons > 15 keV in energy. The only time particles were observed by EPD was in a series of episodic events [0546 to 0638 universal time (UT)] near closest approach (0559:03 UT). Angular distributions were highly anisotropic, ordered by the magnetic field, and showed ions arriving from the hemisphere containing Venus and its bow shock. The spectra showed a power law form with intensities observed into the 120- to 280-keV range. Comparisons with model bow shock calculations show that these energetic ions are associated with the venusian foreshock-bow shock region. Shock-drift acceleration in the venusian bow shock seems the most likely process responsible for the observed ions.
NASA Astrophysics Data System (ADS)
Li, Ming; Liu, Qian; Jia, Zhaojun; Xu, Xuchen; Shi, Yuying; Cheng, Yan; Zheng, Yufeng; Xi, Tingfei; Wei, Shicheng
2013-11-01
Novel ternary graphene oxide-hyaluronic acid-hydroxyapatite (GO-HY-HA) nanocomposite coatings were prepared on Ti substrate using anodic electrophoretic deposition (EPD). Hyaluronic acid was employed as charging additive and dispersion agent during EPD. The kinetics and mechanism of the deposition, and the microstructure of the coated samples were investigated using scanning electron microscopy, X-ray diffraction, Raman spectrum, thermo-gravimetric analysis, and microscopic Fourier transform infrared analysis. The results showed that the addition of GO sheets into the HY-HA suspensions could increase the deposition rate and inhibit cracks creation and propagation in the coatings. The corrosion resistant of the resulting samples were evaluated using potentiodynamic polarization method in simulated body fluid, and the GO-HY-HA coatings could effectively improve the anti-corrosion property of the Ti substrate.
Independent Orbiter Assessment (IOA): Assessment of the orbital maneuvering subsystem, volume 2
NASA Technical Reports Server (NTRS)
Haufler, W. A.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Orbital Maneuvering System (OMS) hardware and electrical power distribution and control (EPD and C), generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. This report documents the results of that comparison for the Orbiter OMS hardware and EPD and C systems. Volume 2 continues the presentation of IOA worksheets and contains the critical items list and the NASA FMEA to IOA worksheet cross reference and recommendations.
Perlen, Susan; Woolhouse, Hannah; Gartland, Deirdre; Brown, Stephanie J
2013-03-01
to investigate the relationship between physical health problems and depressive symptoms in early pregnancy. baseline questionnaire, prospective pregnancy cohort study. six metropolitan public maternity hospitals in Victoria, Australia. 1507 nulliparous women recruited in early pregnancy. nine per cent of women (131/1500) scored ≥ 13 on the EPDS indicating probable clinical depression in early pregnancy (mean gestation=15 weeks). The five most commonly reported physical health problems were as follows: exhaustion (86.9%), morning sickness (64.3%), back pain (45.6%), constipation (43.5%) and severe headaches or migraines (29.5%). Women scoring ≥ 13 on the EPDS reported a mean of six physical health problems compared with a mean of 3.5 among women scoring <13 on the EPDS. Women reporting five or more physical health problems had a three-fold increase in likelihood of reporting depressive symptoms (Adj OR=3.13, 95% CI 2.14-4.58) after adjusting for socio-demographic factors, including maternal age. the findings from this large multi-centre study show that women experiencing a greater number of physical health problems are at increased risk of reporting depressive symptoms in early pregnancy. early detection and support for women experiencing physical and psychological health problems in pregnancy is an important aspect of antenatal care. The extent of co-morbid physical and psychological health problems underlines the need for comprehensive primary health care as an integral component of antenatal care. Copyright © 2012 Elsevier Ltd. All rights reserved.
Perinatal western-type diet and associated gestational weight gain alter postpartum maternal mood.
Bolton, Jessica L; Wiley, Melanie G; Ryan, Bailey; Truong, Samantha; Strait, Melva; Baker, Dana Creighton; Yang, Nancy Y; Ilkayeva, Olga; O'Connell, Thomas M; Wroth, Shelley W; Sánchez, Cristina L; Swamy, Geeta; Newgard, Christopher; Kuhn, Cynthia; Bilbo, Staci D; Simmons, Leigh Ann
2017-10-01
The role of perinatal diet in postpartum maternal mood disorders, including depression and anxiety, remains unclear. We investigated whether perinatal consumption of a Western-type diet (high in fat and branched-chain amino acids [BCAA]) and associated gestational weight gain (GWG) cause serotonin dysregulation in the central nervous system (CNS), resulting in postpartum depression and anxiety (PPD/A). Mouse dams were fed one of four diets (high-fat/high BCAA, low-fat/high BCAA, high-fat, and low-fat) prior to mating and throughout gestation and lactation. Postpartum behavioral assessments were conducted, and plasma and brain tissues assayed. To evaluate potential clinical utility, we conducted preliminary human studies using data from an extant sample of 17 primiparous women with high GWG, comparing across self-reported postpartum mood symptoms using the Edinburgh Postnatal Depression Scale (EPDS) for percent GWG and plasma amino acid levels. Mouse dams fed the high-fat/high BCAA diet gained more weight per kcal consumed, and BCAA-supplemented dams lost weight more slowly postpartum. Dams on BCAA-supplemented diets exhibited increased PPD/A-like behavior, decreased dopaminergic function, and decreased plasma tyrosine and histidine levels when assessed on postnatal day (P)8. Preliminary human data showed that GWG accounted for 29% of the variance in EPDS scores. Histidine was also lower in women with higher EPDS scores. These findings highlight the role of perinatal diet and excess GWG in the development of postpartum mood disorders.
Dolbier, Christyn L.; Rush, Taylor E.; Sahadeo, Latoya S.; Shaffer, Michele L.; Thorp, John
2012-01-01
This study examines the potential racial disparity in postpartum depression (PPD) symptoms among a cohort of non-Hispanic white and African American women after taking into consideration the influence of socioeconomic status (SES). Participants (N = 299) were recruited from maternity clinics serving rural counties, with over-sampling of low SES and African Americans. The Edinburgh Postnatal Depression Scale (EPDS) was administered 1 and 6 months postpartum, and subjective SES scale at 6 months postpartum. Demographic information was collected during enrollment and 1 month postpartum, with updates at 6 months postpartum. Separate logistic regressions were conducted for 1 and 6 month time points for minor-major PPD (EPDS ≥ 10) and major PPD (EPDS > 12); with marital status, poverty, education, subjective SES, and race predictors entered in block sequence. After including all other predictors, race was not a significant predictor of minor-major or major PPD at 1 or 6 months postpartum. Subjective SES was the most consistent predictor of PPD, being significantly associated with minor-major PPD and major PPD at 6 months postpartum, with higher subjective SES indicating lower odds of PPD, even after accounting for all other predictors. This study shows that significant racial disparities were not observed for minor-major or major PPD criteria at 1 or 6 months postpartum. The most consistent and significant predictor of PPD was subjective SES. Implications of these findings for future research, as well as PPD screening and intervention are discussed. PMID:22961387
Are stress-induced cortisol changes during pregnancy associated with postpartum depressive symptoms?
Nierop, Ada; Bratsikas, Aliki; Zimmermann, Roland; Ehlert, Ulrike
2006-01-01
The purpose of this study was to examine the association between psychobiological stress reactivity during healthy pregnancy and depressive symptoms in the early puerperium. A sample of healthy nulliparous pregnant women (N = 57) between the ages of 21 and 35 years underwent a standardized psychosocial stress test during pregnancy. Within an average of 13 days after delivery, postpartum depressive symptoms were assessed using the German version of the Edinburgh postnatal depression scale (EPDS). The sample was divided into a group with probable cases (EPDS score >9, N = 16) and a group with probable noncases (EPDS score < or =9, N = 41). The probable case group showed significantly higher cortisol responses to the stress test compared with the probable noncase group, whereas baseline levels did not differ. Additionally, women in the probable case group showed significantly higher state anxiety and lower mood state throughout the experiment. Furthermore, the probable case group showed higher stress susceptibility, higher trait anxiety, and higher levels in the Symptom Checklist. No differences were found for prior episodes of psychiatric disorders, obstetrical complications, birth weight, or mode of delivery. Our data provide evidence that healthy pregnant women developing postpartum depressive symptoms might already be identified during pregnancy by means of their higher cortisol reactivity and their higher psychological reactivity in response to psychosocial stress. Further investigations are required to explore whether higher psychobiological stress responses not only precede depressive symptoms within 2 weeks after birth, but might also predict postpartum major depression.
NASA Astrophysics Data System (ADS)
Krejci, Alexander J.
Just as ensembles of ordered atoms (a crystal) exhibit collective properties which give rise to phenomena that do not exist for a single atom, the same is true of NP ensembles; ordered arrays of NPs (supercrystals) exhibit properties that are not observed in individual NPs. These collective properties open the door for even more applications for nanomaterials. A few examples that demonstrate this fact will be discussed. In the first example, photoluminescent (PL) optical properties of three CdSe NP systems were studied: one ordered array of NPs, one unordered array, and one system of isolated NPs. In these three systems, the ordered array showed a significantly sharper PL peak compared to the unordered array and the individual NPs. In a second example, the electrical properties for three systems of Ag NPs were studied: one hexagonally packed 2D array of Ag NPs, one cubically packed 2D array, and one individual NP. I-V curves of each system were measured and produced dramatically different behaviors simply due to the change in arrangement of NPs. In a final example, arrays of Ag NPs were created and then sintered. By sintering ordered arrays, it was possible to create large monocrystals of silver; monocrystals could not be created using unordered arrays. These are just three examples that elucidate the control over a wide range of properties that can be achieved by tuning the order within NP ensembles. Given the potential of films composed of ordered NP arrays, many researchers have been investigating how to create and control such arrays using a variety of techniques. For example, ligand-mediated assembly is being studied using a variety of ligands. DNA ligands, in particular, offer a powerful way to control NP assemblies. Evaporative self-assembly has been used to create large supercrystals of one, two, and even more types/sizes of NPs. Assisted assembly incorporating electric and/or magnetic fields has shown promise in creating ordered NP arrays. Spin-casting and Langmuir Blodgett films can be used to create very thin NP films. Templated substrates in combination with spin coating have been used to order blockcopolymers; this could be adapted for NP arrays as well. Some of these techniques can be applied for forming ordered arrays of NPs in two-dimensions, creating nanoparticle monolayers (NPMs), the focus of this work. NPMs are attractive for many applications in devices such as magnetic storage, solar cells, and biosensors. One particularly attractive feature of NPMs is the high surface area to volume ratio of the films. For example, through collaboration, we are investigating PL properties of two monolayers, composed of two different types of NPs, stacked on top of one another. Although challenging, there now are a variety of techniques for the fabrication of NPMs. This dissertation introduces a new process by which one can fabricate monolayers, electrophoretic deposition (EPD). Literature exists on using EPD to fabricate NPMs, but this literature is very limited. One such study deposited films of Au NPs on carbon films and another Pt NPs on carbon films. To the best of our knowledge, only NPMs of metallic NPs on carbon have been fabricated. Of the EPD studies in which NPMs have been fabricated, the technique has not been investigated in depth or has not been generalized for deposition of many types of materials. If NPM formation via EPD could be generalized, the NPMs could be industrially attractive as EPD has many industrially advantageous properties. For instance, EPD is highly versatile in multiple ways: many types of particles can be deposited, the size of the electrodes can be varied over many orders of magnitude, and a large variety of solvents can be used to suspend NPs. For example, our group has deposited materials of different shapes including tubes, sheets, and spheres; different materials such as polymers, metals, semiconductors, and magnetic materials; and on a variety of substrates including steel, silicon, silicon dioxide, indium tin oxide, and gold. In addition, EPD is very simple to perform, forms smooth films, and forms films quite rapidly. By fabricating NPMs of many types of NPs, the technique used herein has proven to be generalizable and thus could be industrially attractive. (Abstract shortened by UMI.)
NIR detection of pits and pit fragments in fresh cherries (abstract)
USDA-ARS?s Scientific Manuscript database
The feasibility of using near infrared (NIR) diffuse reflectance spectroscopy for the detection of pits and pit fragments in cherries was demonstrated. For detection of whole pits, 300 cherries were obtained locally and pits were removed from half. NIR reflectance spectra were obtained in triplicate...
7 CFR 52.779 - Freedom from pits.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Freedom from pits. 52.779 Section 52.779 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Freedom from pits. (a) General. The factor of freedom from pits refers to the incidence of pits and pit...
The effects of pitting on fatigue crack nucleation in 7075-T6 aluminum alloy
NASA Technical Reports Server (NTRS)
Ma, LI; Hoeppner, David W.
1994-01-01
A high-strength aluminum alloy, 7075-T6, was studied to quantitatively evaluate chemical pitting effects of its corrosion fatigue life. The study focused on pit nucleation, pit growth, and fatigue crack nucleation. Pitting corrosion fatigue experiments were conducted in 3.5 percent NaCl aqueous solution under constant amplitude sinusoidal loading at two frequencies, 5 and 20 Hz. Smooth and unnotched specimens were used in this investigation. A video recording system was developed to allow in situ observation of the surface changes of the specimens during testing. The results indicated that pitting corrosion considerably reduces the fatigue strength by accelerating fatigue crack nucleation. A metallographic examination was conducted on the specimens to evaluate the nature of corrosion pits. First, the actual shapes of the corrosion pits were evaluated by cross-sectioning the pits. Secondly, the relation between corrosion pits and microstructure was also investigated. Finally, the possibility of another corrosion mechanism that might be involved in pitting was explored in this investigation. The fractography of the tested specimens showed that corner corrosion pits were responsible for fatigue crack nucleation in the material due to the associated stress concentration. The pits exhibited variance of morphology. Fatigue life for the experimental conditions appeared to be strongly dependent on pitting kinetics and the crack nucleation stage.
Dose-Dependent Dual Role of PIT-1 (POU1F1) in Somatolactotroph Cell Proliferation and Apoptosis
Jullien, Nicolas; Roche, Catherine; Brue, Thierry; Figarella-Branger, Dominique; Graillon, Thomas; Barlier, Anne; Herman, Jean-Paul
2015-01-01
To test the role of wtPIT-1 (PITWT) or PIT-1 (R271W) (PIT271) in somatolactotroph cells, we established, using inducible lentiviral vectors, sublines of GH4C1 somatotroph cells that allow the blockade of the expression of endogenous PIT-1 and/or the expression of PITWT or PIT271, a dominant negative mutant of PIT-1 responsible for Combined Pituitary Hormone Deficiency in patients. Blocking expression of endogenous PIT-1 induced a marked decrease of cell proliferation. Overexpressing PITWT twofold led also to a dose-dependent decrease of cell proliferation that was accompanied by cell death. Expression of PIT271 induced a strong dose-dependent decrease of cell proliferation accompanied by a very pronounced cell death. These actions of PIT271 are independent of its interaction/competition with endogenous PIT-1, as they were unchanged when expression of endogenous PIT-1 was blocked. All these actions are specific for somatolactotroph cells, and could not be observed in heterologous cells. Cell death induced by PITWT or by PIT271 was accompanied by DNA fragmentation, but was not inhibited by inhibitors of caspases, autophagy or necrosis, suggesting that this cell death is a caspase-independent apoptosis. Altogether, our results indicate that under normal conditions PIT-1 is important for the maintenance of cell proliferation, while when expressed at supra-normal levels it induces cell death. Through this dual action, PIT-1 may play a role in the expansion/regression cycles of pituitary lactotroph population during and after lactation. Our results also demonstrate that the so-called “dominant-negative” action of PIT271 is independent of its competition with PIT-1 or a blockade of the actions of the latter, and are actions specific to this mutant variant of PIT-1. PMID:25822178
Rain Erosion Studies of Sapphire, Aluminum Oxynitride, Spinel, Lanthana- Doped Yttria, and TAF Glass
1990-07-01
small , there is little change in average scatter for any material in any test. CONCLUSIONS AND DISCUSSION The principal conclusions are 1. ALON...20 Sample broke erosion damage 10 Slight pitting, 20 No change erosion damage 15 Pitting, cratering, 20 Small surface pits erosion damage 15 Pitting...Sample broke 10 No damage 15 Sample pitted, small edge fracture 15 Slight pitting, 1 crater, 20 Sample pitted, erosion damage small edge fracture 15 SUght
Schulz, M.S.; White, A.F.
1999-01-01
The paucity of weathering rates for quartz in the natural environment stems both from the slow rate at which quartz dissolves and the difficulty in differentiating solute Si contributed by quartz from that derived from other silicate minerals. This study, a first effort in quantifying natural rates of quartz dissolution, takes advantage of extremely rapid tropical weathering, simple regolith mineralogy, and detailed information on hydrologic and chemical transport. Quartz abundances and grain sizes are relatively constant with depth in a thick saprolite. Limited quartz dissolution is indicated by solution rounding of primary angularity and by the formation of etch pits. A low correlation of surface area (0.14 and 0.42 m2 g-1) with grain size indicates that internal microfractures and pitting are the principal contributors to total surface area. Pore water silica concentration increases linearly with depth. On a molar basis, between one and three quarters of pore water silica is derived from quartz with the remainder contributed from biotite weathering. Average solute Si remains thermodynamically undersaturated with respect to recently revised estimates of quartz solubility (17-81 ??M). Etch pitting is more abundant on grains in the upper saprolite and is associated with pore waters lower in dissolved silica. Rate constants describing quartz dissolution increase with decreasing depth (from 10-14.5-10-15.1 mol m-2 s-1), which correlate with both greater thermodynamic undersaturation and increasing etch pit densities. Unlike for many aluminosilicates, the calculated natural weathering rates of quartz fall slightly below the rate constants previously reported for experimental studies (10-12.4-10-14.2 mol m-2 s-1). This agreement reflects the structural simplicity of quartz, dilute solutes, and near-hydrologic saturation.
NASA Astrophysics Data System (ADS)
Simioni, Stephan; Sidler, Rolf; Dual, Jürg; Schweizer, Jürg
2015-04-01
Avalanche control by explosives is among the key temporary preventive measures. Yet, little is known about the mechanism involved in releasing avalanches by the effect of an explosion. Here, we test the hypothesis that the stress induced by acoustic waves exceeds the strength of weak snow layers. Consequently the snow fails and the onset of rapid crack propagation might finally lead to the release of a snow slab avalanche. We performed experiments with explosive charges over a snowpack. We installed microphones above the snowpack to measure near-surface air pressure and accelerometers within three snow pits. We also recorded pit walls of each pit with high speed cameras to detect weak layer failure. Empirical relationships and a priori information from ice and air were used to characterize a porous layered model from density measurements of snow profiles in the snow pits. This model was used to perform two-dimensional numerical simulations of wave propagation in Biot-type porous material. Locations of snow failure were identified in the simulation by comparing the axial and deviatoric stress field of the simulation to the corresponding snow strength. The identified snow failure locations corresponded well with the observed failure locations in the experiment. The acceleration measured in the snowpack best correlated with the modeled acceleration of the fluid relative to the ice frame. Even though the near field of the explosion is expected to be governed by non-linear effects as for example the observed supersonic wave propagation in the air above the snow surface, the results of the linear poroelastic simulation fit well with the measured air pressure and snowpack accelerations. The results of this comparison are an important step towards quantifying the effectiveness of avalanche control by explosives.
NASA Astrophysics Data System (ADS)
An, Qi
Recent advances in the synthesis and characterization of nanostructured composite materials have enabled a broad range of opportunities for engineering the properties of polymer-matrix materials. Carbon nanotubes (CNTs) are known to have exceptional mechanical, electrical and thermal properties. Because of their small size, CNTs can occupy regions between traditional micro-scale reinforcements and create a hierarchical micro/nano structure spanning several orders of magnitude. Since CNTs possess critical reinforcement dimensions below 100 nm, new opportunities exist for tailoring the fiber/matrix interphase regions and ultimately the mechanical and electrical performance of advanced fiber-composites with minimal impact on the fiber-dominated properties. This growing interest in nanoscale hybridization with conventional fiber reinforcement has highlighted the need to develop new processing techniques for successful CNT integration. In this work, a novel and industrially scalable approach for producing multi-scale hybrid carbon nanotube/fiber composites using an electrophoretic deposition (EPD) technique has been studied as an alternative to in situ chemical vapor deposition growth (CVD). EPD is a widely used industrial coating process employed in areas ranging from automotive to electronics production. The method has a number of benefits which include low energy use and the ability to homogenously coat complex shapes with well adhered films of controlled thickness and density. A stable aqueous dispersion of multi-walled carbon nanotubes (MWCNTs) was produced using a novel ozonolysis and ultrasonication (USO) technique that results in dispersion and functionalization in a single step. Networks of CNTs span between adjacent fibers and the resulting composites exhibit significant increases in electrical conductivity and considerable improvements in the interlaminar shear strength and fracture toughness. In order to better understand the underlying mechanisms behind the selective reinforcement of CNTs on the glass-epoxy systems, detailed model interphase study and microdroplet debonding test were conducted to investigate the interfacial properties between an epoxy matrix and glass with the electrophoretically coated CNTs.
Controlled growth of heteroepitaxial zinc oxide nanostructures on gallium nitride.
Kong, Bo Hyun; Kim, Dong Chan; Mohanta, Sanjay Kumar; Han, Won Suk; Cho, Hyung Koun; Hong, Chang-Hee; Kim, Hyung Gu
2009-07-01
ZnO epitaxial layers were grown on GaN underlying films by metalorganic chemical vapor deposition at various temperatures. An increase in growth temperature led to morphological changes from a smooth film with hexagonal-shaped surface pits to honeycomb-like nanostructures with deep hollow, and additionally resulted in a decrease in dislocation density in the interfacial layers. The reduced dislocation density at the higher growth temperature was attributed to an increase in the size of the critical nucleus and the low nucleation density at the initial stage. The shifts in the peak positions in the X-ray diffraction and photoluminescence were also observed in the samples grown at different temperatures, and were caused by the variation of residual strains after the complete coalescence of the nuclei.
Bon, Nina; Couasnay, Greig; Bourgine, Annabelle; Sourice, Sophie; Beck-Cormier, Sarah; Guicheux, Jérôme; Beck, Laurent
2018-02-09
Extracellular phosphate (P i ) can act as a signaling molecule that directly alters gene expression and cellular physiology. The ability of cells or organisms to detect changes in extracellular P i levels implies the existence of a P i -sensing mechanism that signals to the body or individual cell. However, unlike in prokaryotes, yeasts, and plants, the molecular players involved in P i sensing in mammals remain unknown. In this study, we investigated the involvement of the high-affinity, sodium-dependent P i transporters PiT1 and PiT2 in mediating P i signaling in skeletal cells. We found that deletion of PiT1 or PiT2 blunted the P i -dependent ERK1/2-mediated phosphorylation and subsequent gene up-regulation of the mineralization inhibitors matrix Gla protein and osteopontin. This result suggested that both PiTs are necessary for P i signaling. Moreover, the ERK1/2 phosphorylation could be rescued by overexpressing P i transport-deficient PiT mutants. Using cross-linking and bioluminescence resonance energy transfer approaches, we found that PiT1 and PiT2 form high-abundance homodimers and P i -regulated low-abundance heterodimers. Interestingly, in the absence of sodium-dependent P i transport activity, the PiT1-PiT2 heterodimerization was still regulated by extracellular P i levels. Of note, when two putative P i -binding residues, Ser-128 (in PiT1) and Ser-113 (in PiT2), were substituted with alanine, the PiT1-PiT2 heterodimerization was no longer regulated by extracellular P i These observations suggested that P i binding rather than P i uptake may be the key factor in mediating P i signaling through the PiT proteins. Taken together, these results demonstrate that P i -regulated PiT1-PiT2 heterodimerization mediates P i sensing independently of P i uptake. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.
Liang, Huipeng; Li, Wenfang; Luo, Qingchun; Liu, Chaolan; Wu, Zhengyun; Zhang, Wenxue
2015-10-01
The community structure of bacteria in aged and aging pit mud, which was judged according to their sensory and physicochemical characteristics, was analysed using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative real-time PCR (qPCR). The phyla Firmicutes, Actinobacteria, Proteobacteria, Synergistetes and Unclassified Bacteria were detected and the fermentative Firmicutes was predominant in both types of pit mud in the PCR-DGGE analysis. Among Firmicutes, Clostridiales was dominant in aged pit mud while Bacillales and Lactobacillales were dominant in aging pit mud. The diversity of bacterial communities in aged pit mud was higher than that in aging pit mud. In the qPCR analysis the abundance of Clostridium IV in aged pit mud was higher than that in aging pit mud and there were significant differences in the quantity of Clostridium IV between aged and aging pit mud of the same cellar (P < 0.05). There were some significant differences in the microbial community structure between aged and aging pit mud. The differences in the quantity of Clostridium IV might be involved in the distinction that the aged pit mud has a strong aroma while the aging pit mud does not. © 2014 Society of Chemical Industry.
Choat, Brendan; Cobb, Alexander R; Jansen, Steven
2008-01-01
Bordered pits are cavities in the lignified cell walls of xylem conduits (vessels and tracheids) that are essential components in the water-transport system of higher plants. The pit membrane, which lies in the center of each pit, allows water to pass between xylem conduits but limits the spread of embolism and vascular pathogens in the xylem. Averaged across a wide range of species, pits account for > 50% of total xylem hydraulic resistance, indicating that they are an important factor in the overall hydraulic efficiency of plants. The structure of pits varies dramatically across species, with large differences evident in the porosity and thickness of pit membranes. Because greater porosity reduces hydraulic resistance but increases vulnerability to embolism, differences in pit structure are expected to correlate with trade-offs between efficiency and safety of water transport. However, trade-offs in hydraulic function are influenced both by pit-level differences in structure (e.g. average porosity of pit membranes) and by tissue-level changes in conduit allometry (average length, diameter) and the total surface area of pit membranes that connects vessels. In this review we address the impact of variation in pit structure on water transport in plants from the level of individual pits to the whole plant.
PitScan: Computer-Assisted Feature Detection
NASA Astrophysics Data System (ADS)
Wagner, R. V.; Robinson, M. S.
2018-04-01
We developed PitScan to assist in searching the very large LROC image dataset for pits — unusual <200m wide vertical-walled holes in the Moon's surface. PitScan reduces analysts' workload by pre-filtering images to identify possible pits.
NASA Astrophysics Data System (ADS)
Liu, Zhiguo; Yan, Guangyao; Mu, Zhitao; Li, Xudong
2018-01-01
The accelerated pitting corrosion test of 7B04 aluminum alloy specimen was carried out according to the spectrum which simulated airport environment, and the corresponding pitting corrosion damage was obtained and was defined through three parameters A and B and C which respectively denoted the corrosion pit surface length and width and corrosion pit depth. The ratio between three parameters could determine the morphology characteristics of corrosion pits. On this basis the stress concentration factor of typical corrosion pit morphology under certain load conditions was quantitatively analyzed. The research shows that the corrosion pits gradually incline to be ellipse in surface and moderate in depth, and most value of B/A and C/A lies in 1 between 4 and few maximum exceeds 4; The stress concentration factor Kf of corrosion pits is obviously affected by the its morphology, the value of Kf increases with corrosion pits depth increasement under certain corrosion pits surface geometry. Also, the value of Kf decreases with surface width increasement under certain corrosion pits depth. The research conclusion can set theory basis for corrosion fatigue life analysis of aircraft aluminum alloy structure.
Ooeda, Hiroki; Terashima, Ichiro; Taneda, Haruhiko
2017-02-01
Two hypotheses have been proposed to explain the mechanism preventing the refilling vessel water from being drained to the neighboring functional vessels under negative pressure. The pit membrane osmosis hypothesis proposes that the xylem parenchyma cells release polysaccharides that are impermeable to the intervessel pit membranes into the refilling vessel; this osmotically counteracts the negative pressure, thereby allowing the vessel to refill. The pit valve hypothesis proposes that gas trapped within intervessel bordered pits isolates the refilling vessel water from the surrounding functional vessels. Here, using the single-vessel method, we assessed these hypotheses in shoots of mulberry (Morus australis Poir.). First, we confirmed the occurrence of xylem refilling under negative pressure in the potted mulberry saplings. To examine the pit membrane osmosis hypothesis, we estimated the semi-permeability of pit membranes for molecules of various sizes and found that the pit membranes were not semi-permeable to polyethylene glycol of molecular mass <20,000. For the pit valve hypothesis, we formed pit valves in the intervessel pits in the short stem segments and measured the maximum liquid pressure up to which gases in bordered pits were retained. The threshold pressure ranged from 0.025 to 0.10 MPa. These values matched the theoretical value calculated from the geometry of the pit chamber (0.0692-0.101 MPa). Our results suggest that gas in the pits is retained by surface tension, even under substantial positive pressure to resolve gases in the refilling vessel, whereas the molecule size required for the pit membrane osmosis mechanism in mulberry would be unrealistically large. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Acquired pit of the optic nerve: a risk factor for progression of glaucoma.
Ugurlu, S; Weitzman, M; Nduaguba, C; Caprioli, J
1998-04-01
To examine acquired pit of the optic nerve as a risk factor for progression of glaucoma. In a retrospective longitudinal study, 25 open-angle glaucoma patients with acquired pit of the optic nerve were compared with a group of 24 open-angle glaucoma patients without acquired pit of the optic nerve. The patients were matched for age, mean intraocular pressure, baseline ratio of neuroretinal rim area to disk area, visual field damage, and duration of follow-up. Serial optic disk photographs and visual fields of both groups were evaluated by three independent observers for glaucomatous progression. Of 46 acquired pits of the optic nerve in 37 eyes of 25 patients, 36 pits were located inferiorly (76%) and 11 superiorly (24%; P < .001). Progression of optic disk damage occurred in 16 patients (64%) in the group with acquired pit and in three patients (12.5%) in the group without acquired pit (P < .001). Progression of visual field loss occurred in 14 patients (56%) in the group with acquired pit and in six (25%) in the group without pit (P=.04). Bilateral acquired pit of the optic nerve was present in 12 patients (48%). Disk hemorrhages were observed more frequently in the group with acquired pit (10 eyes, 40%) compared with the group without pit (two eyes, 8%; P=.02). Among patients with glaucoma, patients with acquired pit of the optic nerve represent a subgroup who are at increased risk for progressive optic disk damage and visual field loss.
Parturition pit: the bony imprint of vaginal birth.
McArthur, Tatum A; Meyer, Isuzu; Jackson, Bradford; Pitt, Michael J; Larrison, Matthew C
2016-09-01
To retrospectively evaluate for pits along the dorsum of the pubic body in females and compare the presence/absence of these pits to vaginal birth data. We retrospectively reviewed females with vaginal birth data who underwent pelvic CT. The presence of pits along the dorsum of the pubic body, pit grade (0 = not present; 1 = faintly imperceptible; 2 = present; 3 = prominent), and the presence of osteitis condensans ilii, preauricular sulcus, and sacroiliac joint vacuum phenomenon were assessed on imaging. Musculoskeletal radiologists who were blinded to the birth data evaluated the CTs. 48 males were also evaluated for the presence of pits. 482 female patients underwent CT pelvis and 171 were excluded due to lack of vaginal birth data. Of the 311 study patients, 262 had prior vaginal birth(s) and 194 had pits on CT. Only 7 of the 49 patients without prior vaginal birth had pits. There was a statistically significant association between vaginal birth and presence of pits (p < 0.0001). Patients with more prominent pits (grades 2/3) had a greater number of vaginal births. As vaginal deliveries increased, the odds of having parturition pits greatly increased, adjusting for age and race at CT (p < 0.0001). No males had pits. Our study indicates that parturition pits are associated with prior vaginal birth and should be considered a characteristic of the female pelvis. The lytic appearance of prominent pits on imaging can simulate disease and create a diagnostic dilemma for interpreting radiologists.
Parturition Pit: The Bony Imprint of Vaginal Birth
Meyer, Isuzu; Jackson, Bradford; Pitt, Michael J.; Larrison, Matthew C.
2017-01-01
Purpose To retrospectively evaluate for pits along the dorsum of the pubic body in females and compare the presence/absence of these pits to vaginal birth data. Materials and Methods We retrospectively reviewed females with vaginal birth data who underwent pelvic CT. The presence of pits along the dorsum of the pubic body, pit grade (0 = not present; 1 = faintly imperceptible; 2 = present; 3 = prominent), and the presence of osteitis condensans ilii, preauricular sulcus, and sacroiliac joint vacuum phenomenon were assessed on imaging. Musculoskeletal radiologists who were blinded to the birth data evaluated the CTs. 48 males were also evaluated for the presence of pits. Results 482 female patients underwent CT pelvis and 171 were excluded due to lack of vaginal birth data. Of the 311 study patients, 262 had prior vaginal birth(s) and 194 had pits on CT. Only 7 of the 49 patients without prior vaginal birth had pits. There was a statistically significant association between vaginal birth and presence of pits (p<0.0001). Patients with more prominent pits (grades 2/3) had a greater number of vaginal births. As vaginal deliveries increased, the odds of having parturition pits greatly increased, adjusting for age and race at CT (p<0.0001). No males had pits. Conclusion Our study indicates that parturition pits are associated prior vaginal birth and should be considered a characteristic of the female pelvis. The lytic appearance of prominent pits on imaging can simulate disease and create a diagnostic dilemma for interpreting radiologists. PMID:27270921
The effect of normal pulsed Nd-YAG laser irradiation on pits and fissures in human teeth.
Bahar, A; Tagomori, S
1994-01-01
The effects of normal pulsed Nd-YAG laser irradiation on the acid resistance of human dental enamel of pits and fissures, the cleaning of the pit and fissure contents and fluoride uptake into deep pits and fissures were examined. The acid resistance of the pit and fissure enamel was evaluated by the amount of dissolved calcium per square millimeter of the surface area. The pit and fissure enamel treated with laser irradiation obtained an acid resistance 30% higher than that of the unlased controls. The cleaning effect of laser irradiation on the pit and fissure contents was compared with chemicomechanical and mechanical methods. The laser irradiation was found to clean the pits and fissures to a greater depth without alterating the shape of pits and fissures, compared with the other two methods. The distribution of calcium, phosphorus and fluoride in the enamel of the pits and fissures was then measured by electron probe microanalyzer. At the entrance and in the deep part of the pits and fissures, the fluoride content of the enamel treated with acidulated phosphate fluoride after laser irradiation was higher than that of the enamel treated with acidulated phosphate fluoride alone. These results thus suggest that Nd-YAG laser irradiation might be effective in increasing the acid resistance of the pit and fissure enamel, while removing the pit and fissure debris contents and increasing the fluoride uptake into the pit and fissure enamel.
Liu, Yao; Chu, Hong-yan; Wang, Danqian; Ma, Han; Sun, Wei
2017-01-01
In this study, the pitting behaviour of a new corrosion-resistant alloy steel (CR) is compared to that of low-carbon steel (LC) in a simulated concrete pore solution with a chloride concentration of 5 mol/L. The electrochemical behaviour of the bars was characterised using linear polarisation resistance (LPR) and electrochemical impedance spectroscopy (EIS). The pitting profiles were detected by reflective digital holographic microscopy (DHM), scanning electron microscopy (SEM), and the chemical components produced in the pitting process were analysed by X-ray energy dispersive spectroscopy (EDS). The results show that the CR bars have a higher resistance to pitting corrosion than the LC bars. This is primarily because of the periodic occurrence of metastable pitting during pitting development. Compared to the pitting process in the LC bars, the pitting depth grows slowly in the CR bars, which greatly reduces the risk of pitting. The possible reason for this result is that the capability of the CR bars to heal the passivation film helps to restore the metastable pits to the passivation state. PMID:28777327
Pitting corrosion as a mixed system: coupled deterministic-probabilistic simulation of pit growth
NASA Astrophysics Data System (ADS)
Ibrahim, Israr B. M.; Fonna, S.; Pidaparti, R.
2018-05-01
Stochastic behavior of pitting corrosion poses a unique challenge in its computational analysis. However, it also stems from electrochemical activity causing general corrosion. In this paper, a framework for corrosion pit growth simulation based on the coupling of the Cellular Automaton (CA) and Boundary Element Methods (BEM) is presented. The framework assumes that pitting corrosion is controlled by electrochemical activity inside the pit cavity. The BEM provides the prediction of electrochemical activity given the geometrical data and polarization curves, while the CA is used to simulate the evolution of pit shapes based on electrochemical activity provided by BEM. To demonstrate the methodology, a sample case of local corrosion cells formed in pitting corrosion with varied dimensions and polarization functions is considered. Results show certain shapes tend to grow in certain types of environments. Some pit shapes appear to pose a higher risk by being potentially significant stress raisers or potentially increasing the rate of corrosion under the surface. Furthermore, these pits are comparable to commonly observed pit shapes in general corrosion environments.
Experimental research on micro-pit defects of SUS 430 stainless steel strip in cold rolling process
NASA Astrophysics Data System (ADS)
Li, Changsheng; Li, Miao; Zhu, Tao; Huo, Gang
2013-05-01
In order to improve surface glossiness of stainless steel strip in tandem cold rolling, experimental research on micro-pit defects of SUS 430 ferrite stainless steel was investigated in laboratory. The surface morphology of micro-pit defects was observed by SEM. The effects of micro-pit defects on rolling reduction, roll surface roughness and emulsion parameters were analyzed. With the pass number increasing, the quantity and surface of micro-pit defects were reduced, uneven peak was decreased and gently along rolling direction, micro-pit defects had equally distributed tendency along tranverse direction. The micro-pit defects were increased with the roll surface roughness increase. The defects ratio was declined with larger gradient at pass number 1 to 3, but gentle slope at pass number 4 to 5. The effects of temperature 55° and 63°, concentration 3% and 6% of emulsion on micro-pit effects had not obvious difference. Maintain of micro-pit was effected by rolling oil or air in the micro-pit, the quality of oil was much more than the air in the micro-pit in lubrication rolling.
Distribution, morphology, and origins of Martian pit crater chains
NASA Astrophysics Data System (ADS)
Wyrick, Danielle; Ferrill, David A.; Morris, Alan P.; Colton, Shannon L.; Sims, Darrell W.
2004-06-01
Pit craters are circular to elliptical depressions found in alignments (chains), which in many cases coalesce into linear troughs. They are common on the surface of Mars and similar to features observed on Earth and other terrestrial bodies. Pit craters lack an elevated rim, ejecta deposits, or lava flows that are associated with impact craters or calderas. It is generally agreed that the pits are formed by collapse into a subsurface cavity or explosive eruption. Hypotheses regarding the formation of pit crater chains require development of a substantial subsurface void to accommodate collapse of the overlying material. Suggested mechanisms of formation include: collapsed lava tubes, dike swarms, collapsed magma chamber, substrate dissolution (analogous to terrestrial karst), fissuring beneath loose material, and dilational faulting. The research described here is intended to constrain current interpretations of pit crater chain formation by analyzing their distribution and morphology. The western hemisphere of Mars was systematically mapped using Mars Orbiter Camera (MOC) images to generate ArcView™ Geographic Information System (GIS) coverages. All visible pit crater chains were mapped, including their orientations and associations with other structures. We found that pit chains commonly occur in areas that show regional extension or local fissuring. There is a strong correlation between pit chains and fault-bounded grabens. Frequently, there are transitions along strike from (1) visible faulting to (2) faults and pits to (3) pits alone. We performed a detailed quantitative analysis of pit crater morphology using MOC narrow angle images, Thermal Emission Imaging System (THEMIS) visual images, and Mars Orbiter Laser Altimeter (MOLA) data. This allowed us to determine a pattern of pit chain evolution and calculate pit depth, slope, and volume. Volumes of approximately 150 pits from five areas were calculated to determine volume size distribution and regional trends. The information collected in the study was then compared with non-Martian examples of pit chains and physical analog models. We evaluated the various mechanisms for pit chain development based on the data collected and conclude that dilational normal faulting and sub-vertical fissuring provide the simplest and most comprehensive mechanisms to explain the regional associations, detailed geometry, and progression of pit chain development.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mark Krauss and Catherine Birney
2011-05-01
This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 544: Cellars, Mud Pits, and Oil Spills, Nevada National Security Site, Nevada. This CR complies with the requirements of the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. The corrective action sites (CASs) within CAU 544 are located within Areas 2, 7, 9, 10, 12, 19, and 20 of the Nevada National Security Site. Corrective Action Unit 544 comprises the following CASs: • 02-37-08,more » Cellar & Mud Pit • 02-37-09, Cellar & Mud Pit • 07-09-01, Mud Pit • 09-09-46, U-9itsx20 PS #1A Mud Pit • 10-09-01, Mud Pit • 12-09-03, Mud Pit • 19-09-01, Mud Pits (2) • 19-09-03, Mud Pit • 19-09-04, Mud Pit • 19-25-01, Oil Spill • 19-99-06, Waste Spill • 20-09-01, Mud Pits (2) • 20-09-02, Mud Pit • 20-09-03, Mud Pit • 20-09-04, Mud Pits (2) • 20-09-06, Mud Pit • 20-09-07, Mud Pit • 20-09-10, Mud Pit • 20-25-04, Oil Spills • 20-25-05, Oil Spills The purpose of this CR is to provide documentation supporting the completed corrective actions and data confirming that the closure objectives for CASs within CAU 544 were met. To achieve this, the following actions were performed: • Review the current site conditions, including the concentration and extent of contamination. • Implement any corrective actions necessary to protect human health and the environment. • Properly dispose of corrective action and investigation wastes. • Document Notice of Completion and closure of CAU 544 issued by the Nevada Division of Environmental Protection.« less
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1987-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Distribution and Control (EPD and C) hardware. The EPD and C hardware performs the functions of distributing, sensing, and controlling 28 volt DC power and of inverting, distributing, sensing, and controlling 117 volt 400 Hz AC power to all Orbiter subsystems from the three fuel cells in the Electrical Power Generation (EPG) subsystem. Volume 2 continues the presentation of IOA analysis worksheets and contains the potential critical items list.
Perinatal depression and screening among Aboriginal Australians in the Kimberley.
Kotz, Jayne; Munns, Ailsa; Marriott, Rhonda; Marley, Julia V
2016-02-01
Adhoc culturally questionable perinatal mental-health screening among Aboriginal women in the Kimberley. Mental-health issues, substance abuse and suicide attempts are high among young Aboriginal women in Australia. There is no evidence that the Edinburgh Postnatal Depression Scale (EPDS) is effective or culturally safe. Screening practices are complicated by limited understanding of the complex cultural interface between Western and Aboriginal beliefs and notions about health and mental-health. What is the current context of perinatal mental-health screening practices among Aboriginal women in the Kimberley and what might be considered a culturally safe approach? A review of the literature and exploration of current screening practices preceded community participatory action research (CPAR) of perinatal mental-health screening. More than 100 Kimberley women and 72 health practitioners contributed to this joint strategic body of work. Recommendations for practice include one single culturally appropriate Kimberley version of the EPDS.
Postpartum depression and traditional postpartum care in China: role of zuoyuezi.
Wan, Ellen Y; Moyer, Cheryl A; Harlow, Siobán D; Fan, Zitian; Jie, Yan; Yang, Huixia
2009-03-01
To determine the relationship between the traditional Chinese practice of postpartum care, known as zuoyuezi, and postpartum depression (PPD) in China. A total of 342 Chinese women were surveyed 6- to 8-weeks post partum using the Edinburgh Postnatal Depression Scale (EPDS) and items assessing sociodemographics, health history, peripartum experiences, zuoyuezi, and social support. Prevalence of PPD was 15.5% (EPDS cutoff >or=13). PPD was associated with lower income, difficult pregnancy experience, poor infant health status, not attending childbirth classes, and low spousal involvement before and after delivery. Among the 96% of women who practiced zuoyuezi, those for whom the caregiver was her mother-in-law or who perceived zuoyuezi as unhelpful had twice the odds of PPD. These data highlight the importance of the peripartum experience in assessing PPD risk. Zuoyuezi is still commonly practiced in urban China, and further research is needed to explore its role in the potential prevention of PPD.
NASA Technical Reports Server (NTRS)
Schmeckpeper, K. R.
1988-01-01
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA first completed an analysis of the Electrical Power Distribution and Control (EPD and C) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. A resolution of each discrepancy from the comparison is provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPD and C hardware. Volume 3 continues the presentation of IOA worksheets and contains the potential critical items list and the NASA FMEA to IOA worksheet cross reference and recommendations.
NASA Technical Reports Server (NTRS)
Swimm, Randall; Garrett, Henry B.; Jun, Insoo; Evans, Robin W.
2004-01-01
In this study we examine ten-minute omni-directional averages of energetic electron data measured by the Galileo spacecraft Energetic Particle Detector (EPD). Count rates from electron channels B1, DC2, and DC3 are evaluated using a power law model to yield estimates of the differential electron fluxes from 1 MeV to 11 MeV at distances between 8 and 51 Jupiter radii. Whereas the orbit of the Galileo spacecraft remained close to the rotational equatorial plane of Jupiter, the approximately 11 degree tilt of the magnetic axis of Jupiter relative to its rotational axis allowed the EPD instrument to sample high energy electrons at limited distances normal to the magnetic equatorial plane. We present a Fourier analysis of the semi-diurnal variation of electron fluxes with longitude.
Investigating pitting in X65 carbon steel using potentiostatic polarisation
NASA Astrophysics Data System (ADS)
Mohammed, Sikiru; Hua, Yong; Barker, R.; Neville, A.
2017-11-01
Although pitting corrosion in passive materials is generally well understood, the growth of surface pits in actively-corroding materials has received much less attention to date and remains poorly understood. One of the key challenges which exists is repeatedly and reliably generating surface pits in a practical time-frame in the absence of deformation and/or residual stress so that studies on pit propagation and healing can be performed. Another pertinent issue is how to evaluate pitting while addressing general corrosion in low carbon steel. In this work, potentiostatic polarisation was employed to induce corrosion pits (free from deformation or residual stress) on actively corroding X65 carbon steel. The influence of applied potential (50 mV, 100 mV and 150 mV vs open circuit potential) was investigated over 24 h in a CO2-saturated, 3.5 wt.% NaCl solution at 30 °C and pH 3.8. Scanning electron microscopy (SEM) was utilised to examine pits, while surface profilometry was conducted to measure pit depth as a function of applied potential over the range considered. Analyses of light pitting (up to 120 μm) revealed that pit depth increased linearly with increase in applied potential. This paper relates total pit volume (measured using white light interferometry) to dissipated charge or total mass loss (using the current response for potentiostatic polarisation in conjunction with Faraday's law). By controlling the potential of the surface (anodic) the extent of pitting and general corrosion could be controlled. This allowed pits to be evaluated for their ability to continue to propagate after the potentiostatic technique was employed. Linear growth from a depth of 70 μm at pH 3.8, 80 °C was demonstrated. The technique offers promise for the study of inhibition of pitting.
Morphology and Evolution of Sublimation Pits on Pluto
NASA Astrophysics Data System (ADS)
Abu-Hashmeh, N.; Conrad, J. W.; Nimmo, F.; Moore, J. M.; Stern, A.; Olkin, C.; Weaver, H. A., Jr.; Ennico Smith, K.; Young, L. A.
2017-12-01
Pluto's Sputnik Planitia region hosts a geologically young surface of nitrogen ice that exhibits striking pitted terrain (Moore et al., Science 351, 2016). These pits are most likely formed by sublimation due to incident sunlight, similar to the southern polar cap of Mars (Byrne and Ingersoll, Science 299, 2003); however, their evolution over time has resulted in unique morphological characteristics. Motivated by this, we used the high-resolution mosaic strips captured by New Horizons' Long Range Reconnaissance Imager (LORRI) to map sublimation pits in the southernmost region of Sputnik Planitia. Statistical data shows pit orientations appearing North-South dominant; their morphology also indicates extensional evolution along the major axis caused by further sublimation and contact-coalescence processes. Qualitative analysis of the region yielded indications of an evolutionary path for individual pits that coalesce into each other and exhibit an elongated end-stage. Additionally, densely-pitted regions generally appear to correlate with regions containing longer pits, implying that coalescence may be an important process for elongation. We also model the evolution geometry through competing effects of diffusion (viscous relaxation) and retreat (sublimation) (Buhler and Ingersoll, LPSC Abstract #1746, 2017). The model demonstrates single-pit and coalescing-pit evolutions that influence overall length, as well as a potential ability for the pit center to move in space while the pit morphology evolves.
NASA Astrophysics Data System (ADS)
Dzwairo, Bloodless; Hoko, Zvikomborero; Love, David; Guzha, Edward
In resource-poor and low-population-density areas, on-site sanitation is preferred to off-site sanitation and groundwater is the main source of water for domestic uses. Groundwater pollution potential from on-site sanitation in such areas conflicts with Integrated Water Resources Management (IWRM) principles that advocate for sustainable use of water resources. Given the widespread use of groundwater for domestic purposes in rural areas, maintaining groundwater quality is a critical livelihood intervention. This study assessed impacts of pit latrines on groundwater quality in Kamangira village, Marondera district, Zimbabwe. Groundwater samples from 14 monitoring boreholes and 3 shallow wells were analysed during 6 sampling campaigns, from February 2005 to May 2005. Parameters analysed were total and faecal coliforms, NH4+-N, NO3--N, conductivity, turbidity and pH, both for boreholes and shallow wells. Total and faecal coliforms both ranged 0-TNTC (too-numerous-to-count), 78% of results meeting the 0 CFU/100 ml WHO guidelines value. NH4+-N range was 0-2.0 mg/l, with 99% of results falling below the 1.5 mg/l WHO recommended value. NO3--N range was 0.0-6.7 mg/l, within 10 mg/l WHO guidelines value. The range for conductivity values was 46-370 μS/cm while the pH range was 6.8-7.9. There are no WHO guideline values for these two parameters. Turbidity ranged from 1 NTU to 45 NTU, 59% of results meeting the 5 NTU WHO guidelines limit. Depth from the ground surface to the water table for the period February 2005 to May 2005 was determined for all sampling points using a tape measure. The drop in water table averaged from 1.1 m to 1.9 m and these values were obtained by subtracting water table elevations from absolute ground surface elevation. Soil from the monitoring boreholes was classified as sandy. The soil infiltration layer was taken as the layer between the pit latrine bottom and the water table. It averaged from 1.3 m to 1.7 m above the water table for two latrines and 2-3.2 m below it for one pit latrine. A questionnaire survey revealed the prevalence of diarrhoea and structural failure of latrines. Results indicated that pit latrines were microbiologically impacting on groundwater quality up to 25 m lateral distance. Nitrogen values were of no immediate threat to health. The shallow water table increased pollution potential from pit latrines. Raised and lined pit latrines and other low-cost technologies should be considered to minimize potential of groundwater pollution.
High efficiency, low cost, thin film silicon solar cell design and method for making
Sopori, Bhushan L.
2001-01-01
A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.
High efficiency low cost thin film silicon solar cell design and method for making
Sopori, Bhushan L.
1999-01-01
A semiconductor device having a substrate, a conductive intermediate layer deposited onto said substrate, wherein the intermediate layer serves as a back electrode, an optical reflector, and an interface for impurity gettering, and a semiconductor layer deposited onto said intermediate layer, wherein the semiconductor layer has a grain size at least as large as the layer thickness, and preferably about ten times the layer thickness. The device is formed by depositing a metal layer on a substrate, depositing a semiconductive material on the metal-coated substrate to produce a composite structure, and then optically processing the composite structure by illuminating it with infrared electromagnetic radiation according to a unique time-energy profile that first produces pits in the backside surface of the semiconductor material, then produces a thin, highly reflective, low resistivity alloy layer over the entire area of the interface between the semiconductor material and the metal layer, and finally produces a grain-enhanced semiconductor layer. The time-energy profile includes increasing the energy to a first energy level to initiate pit formation and create the desired pit size and density, then ramping up to a second energy level in which the entire device is heated to produce an interfacial melt, and finally reducing the energy to a third energy level and holding for a period of time to allow enhancement in the grain size of the semiconductor layer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wood, Kevin N.; Kazyak, Eric; Chadwick, Alexander F.
Enabling ultra-high energy density rechargeable Li batteries would have widespread impact on society. But, the critical challenges of Li metal anodes (most notably cycle life and safety) remain unsolved. This is attributed to the evolution of Li metal morphology during cycling, which leads to dendrite growth and surface pitting. Herein, we present a comprehensive understanding of the voltage variations observed during Li metal cycling, which is directly correlated to morphology evolution through the use of operando video microscopy. A custom-designed visualization cell was developed to enable operando synchronized observation of Li metal electrode morphology and electrochemical behavior during cycling. Amore » mechanistic understanding of the complex behavior of these electrodes is gained through correlation with continuum-scale modeling, which provides insight into the dominant surface kinetics. Our work provides a detailed explanation of (1) when dendrite nucleation occurs, (2) how those dendrites evolve as a function of time, (3) when surface pitting occurs during Li electrodissolution, (4) kinetic parameters that dictate overpotential as the electrode morphology evolves, and (5) how this understanding can be applied to evaluate electrode performance in a variety of electrolytes. Our results provide detailed insight into the interplay between morphology and the dominant electrochemical processes occurring on the Li electrode surface through an improved understanding of changes in cell voltage, which represents a powerful new platform for analysis.« less
Wood, Kevin N.; Kazyak, Eric; Chadwick, Alexander F.; ...
2015-10-14
Enabling ultra-high energy density rechargeable Li batteries would have widespread impact on society. But, the critical challenges of Li metal anodes (most notably cycle life and safety) remain unsolved. This is attributed to the evolution of Li metal morphology during cycling, which leads to dendrite growth and surface pitting. Herein, we present a comprehensive understanding of the voltage variations observed during Li metal cycling, which is directly correlated to morphology evolution through the use of operando video microscopy. A custom-designed visualization cell was developed to enable operando synchronized observation of Li metal electrode morphology and electrochemical behavior during cycling. Amore » mechanistic understanding of the complex behavior of these electrodes is gained through correlation with continuum-scale modeling, which provides insight into the dominant surface kinetics. Our work provides a detailed explanation of (1) when dendrite nucleation occurs, (2) how those dendrites evolve as a function of time, (3) when surface pitting occurs during Li electrodissolution, (4) kinetic parameters that dictate overpotential as the electrode morphology evolves, and (5) how this understanding can be applied to evaluate electrode performance in a variety of electrolytes. Our results provide detailed insight into the interplay between morphology and the dominant electrochemical processes occurring on the Li electrode surface through an improved understanding of changes in cell voltage, which represents a powerful new platform for analysis.« less
Santiago, Michael; Pagay, Vinay; Stroock, Abraham D
2013-10-01
In perfusion experiments, the hydraulic conductance of stem segments ( ) responds to changes in the properties of the perfusate, such as the ionic strength ( ), pH, and cationic identity. We review the experimental and theoretical work on this phenomenon. We then proceed to explore the hypothesis that electrokinetic effects in the bordered pit membrane (BPM) contribute to this response. In particular, we develop a model based on electroviscosity in which hydraulic conductance of an electrically charged porous membrane varies with the properties of the electrolyte. We use standard electrokinetic theory, coupled with measurements of electrokinetic properties of plant materials from the literature, to determine how the conductance of BPMs, and therefore , may change due to electroviscosity. We predict a nonmonotonic variation of with with a maximum reduction of 18%. We explore how this reduction depends on the characteristics of the sap and features of the BPM, such as pore size, density of chargeable sites, and their dissociation constant. Our predictions are consistent with changes in observed for physiological values of sap and pH. We conclude that electroviscosity is likely responsible, at least partially, for the electrolyte dependence of conductance through pits and that electroviscosity may be strong enough to play an important role in other transport processes in xylem. We conclude by proposing experiments to differentiate the impact of electroviscosity on from that of other proposed mechanisms.
Di Florio, A.; Putnam, K.; Altemus, M.; Apter, G.; Bergink, V.; Bilszta, J.; Brock, R.; Buist, A.; Deligiannidis, K. M.; Devouche, E.; Epperson, C. N.; Guille, C.; Kim, D.; Lichtenstein, P.; Magnusson, P. K. E.; Martinez, P.; Munk-Olsen, T.; Newport, J.; Payne, J.; Penninx, B. W.; O’Hara, M.; Robertson-Blackmore, E.; Roza, S. J.; Sharkey, K. M.; Stuart, S.; Tiemeier, H.; Viktorin, A.; Schmidt, P. J.; Sullivan, P. F.; Stowe, Z. N.; Wisner, K. L.; Jones, I.; Rubinow, D. R.; Meltzer-Brody, S.
2017-01-01
Background Universal screening for postpartum depression is recommended in many countries. Knowledge of whether the disclosure of depressive symptoms in the postpartum period differs across cultures could improve detection and provide new insights into the pathogenesis. Moreover, it is a necessary step to evaluate the universal use of screening instruments in research and clinical practice. In the current study we sought to assess whether the Edinburgh Postnatal Depression Scale (EPDS), the most widely used screening tool for postpartum depression, measures the same underlying construct across cultural groups in a large international dataset. Method Ordinal regression and measurement invariance were used to explore the association between culture, operationalized as education, ethnicity/race and continent, and endorsement of depressive symptoms using the EPDS on 8209 new mothers from Europe and the USA. Results Education, but not ethnicity/race, influenced the reporting of postpartum depression [difference between robust comparative fit indexes (Δ*CFI) < 0.01]. The structure of EPDS responses significantly differed between Europe and the USA (Δ*CFI > 0.01), but not between European countries (Δ*CFI < 0.01). Conclusions Investigators and clinicians should be aware of the potential differences in expression of phenotype of postpartum depression that women of different educational backgrounds may manifest. The increasing cultural heterogeneity of societies together with the tendency towards globalization requires a culturally sensitive approach to patients, research and policies, that takes into account, beyond rhetoric, the context of a person’s experiences and the context in which the research is conducted. PMID:27866476
[Quality of life of women depressed in the post-partum period].
Rojas, Graciela; Fritsch, Rosemarie; Solís, Jaime; González, Marcos; Guajardo, Viviana; Araya, Ricardo
2006-06-01
Depression is common among women, specially during breeding. To characterize post-partum depression in a group of women attending a primary health care clinic and its relationship to quality of life. The sample included women meeting criteria for Major Depression, with a child of up to 11 months old. Exclusion criteria included the presence of psychosis, history of mania, alcohol abuse, illegal drug use, high suicide risk, and receiving mental health care in the last three months. Structured interviews used were the Edinburgh postpartum depression scale (EPDS), Mini International Neuropsychiatric Interview (MINI), Medical Outcomes Study Questionnaire (SF-36) and questions about incapacity and health care use. The sample included 159 women with a median age of 27 years (range: 16-43 years). Thirty three percent were married, 30.8% lived in common law marriage, 9.4% were divorced, and 26.4% were single. Most (89.3%) were housewives, 31% were students, and 6.9% were employed. The average score on the EPDS was 17 points (S.D. 4.2). The average SF-36 somatic score was 42.7 points (S.D. 8.2), and the emotional score was 30.3 (D.S. 0.3). The relation between the average score on the EPDS and the somatic and emotional scores was statistically significant (p=0.000-0.006). Most women were mildly to moderately depressed. Their depression was associated with a marked impairment of activities of daily living. These findings add to the evidence suggesting that depression is associated with marked disability cultures, even when the depression is mild to moderate.
Genetic and epigenetic associations of MAOA and NR3C1 with depression and childhood adversities.
Melas, Philippe A; Wei, Yabin; Wong, Chloe C Y; Sjöholm, Louise K; Åberg, Elin; Mill, Jonathan; Schalling, Martin; Forsell, Yvonne; Lavebratt, Catharina
2013-08-01
Monoamine oxidase A (MAOA) harbours a polymorphic upstream variable-number tandem repeat (u-VNTR). The MAOA-L allele of the u-VNTR leads to decreased gene expression levels in vitro and has been found to increase the risk of conduct disorder in males with childhood adversities. Early-life adversities have been associated with hypermethylation of the glucocorticoid receptor (NR3C1). In this study, we first performed a genetic association analysis of the MAOA u-VNTR using individuals with depression (n = 392) and controls (n = 1276). Next, DNA methylation analyses of MAOA and NR3C1 were performed using saliva samples of depressed and control subgroups. Adult MAOA-L females with childhood adversities were found to have a higher risk of developing depression (p = 0.006) and overall MAOA methylation levels were decreased in depressed females compared to controls (mean depressed, 42% vs. mean controls, 44%; p = 0.04). One specific childhood adversity [early parental death (EPD)] was associated with hypermethylation of NR3C1 close to an NGFI-A binding site (mean EPD, 19% vs. mean non-EPD, 14%; p = 0.005). Regression analysis indicated that this association may be mediated by the MAOA-L allele (adjusted R² = 0.24, ANOVA: F = 23.48, p < 0.001). Conclusively: (1) depression in females may result from a gene × childhood-adversity interaction and/or a dysregulated epigenetic programming of MAOA; (2) childhood-adversity subtypes may differentially impact DNA methylation at NR3C1; (3) baseline MAOA-genotypic variations may affect the extent of NR3C1 methylation.
Predictors of Postpartum Depression Among Immigrant Women in the Year After Childbirth.
Ganann, Rebecca; Sword, Wendy; Thabane, Lehana; Newbold, Bruce; Black, Margaret
2016-02-01
Immigrant women are at increased risk for postpartum depression (PPD). The factors that influence PPD among immigrant women are poorly understood. The purpose of this study was to identify individual- and community-level factors predictive of PPD among immigrant women living in a large Ontario city at 6 weeks, 6 months, and 1 year postpartum. The study involved a secondary analysis of a prospective cohort study, The Ontario Mother and Infant Study 3. This study included 519 immigrant women who were recruited from two hospitals in one urban city and delivered full-term singleton infants. Women completed a written questionnaire in hospital, followed by structured telephone interviews at 6 weeks, 6 months, and 1 year after hospital discharge. Generalized estimating equations were used to explore factors associated with PPD, measured using the Edinburgh Postnatal Depression Scale (EPDS) and two thresholds for depression (≥12 and ≥9). Rates of PPD at all time points were 8%-10% for EPDS scores of ≥12. For EPDS scores of ≥9, rates of PPD more than doubled at all time points. A lack of social support was strongly associated with PPD in all analyses. Living in Canada for ≤2 years, poor perceptions of health, and lower mental health functioning were other important predictors of PPD. Living in communities with a high prevalence of immigrants and low income also was associated with PPD. Complex individual and community-level factors are associated with PPD in immigrant women. Understanding these contextual factors can inform a multifaceted approach to addressing PPD.
Teo, Cherlyen; Chia, Ai-Ru; Colega, Marjorelee T; Chen, Ling-Wei; Fok, Doris; Pang, Wei Wei; Godfrey, Keith M; Tan, Kok Hian; Yap, Fabian; Shek, Lynette Pei-Chi; Chong, Yap-Seng; Meaney, Michael; Chen, Helen; Chong, Mary Foong-Fong
2018-03-02
Diet in the first month postpartum, otherwise known as "the confinement diet" in Asia, has unique characteristics that are influenced by traditions, cultures, and beliefs. We aimed to characterize dietary patterns during confinement period in a multi-ethnic Asian cohort and examined their associations with postpartum depression (PPD) and anxiety (PPA). Dietary intakes of 490 women were ascertained in the first month postpartum using 3-day food diaries and dietary patterns were derived by factor analysis. Participants completed the Edinburgh Postnatal Depression Scale (EPDS) and State-Trait Anxiety Inventory (STAI) at three months' postpartum; higher scores are indicative of more depressive and anxiety symptoms, respectively. Four dietary patterns were identified: Traditional-Chinese-Confinement diet, Traditional-Indian-Confinement diet, Eat-Out diet and Soup-Vegetables-Fruits diet. The Traditional-Indian-Confinement diet was associated with less PPD symptoms [β (95% CI) -0.62 (-1.16, -0.09) EPDS score per SD increase in diet score] and a non-significant trend with reduced probable PPD (EPDS scores ≥ 13) [OR (95% CI) 0.56 (0.31, 1.01)]. The Soup-Vegetables-Fruits diet was associated with less PPA symptoms [β (95% CI) -1.49 (-2.56, -0.42) STAI-state score]. No associations were observed for other dietary patterns. Independent of ethnicity, adherence to the Traditional-Indian-Confinement diet that is characterized by intake of herbs and legumes, and Soup-Vegetables-Fruits diet high in fruits, vegetables and fish during the postpartum period were associated with less PPD and PPA symptoms, respectively.
Maliszewska, Karolina; Świątkowska-Freund, Małgorzata; Bidzan, Mariola; Krzysztof, Preis
2017-10-29
To investigate the likelihood of postpartum depression and to explore maternal characteristics in terms of personality, social support and other medical and psychological data. A sample of 548 patients was investigated 4 weeks and 3 months after delivery. They responded to questionnaires containing sociodemographic questions: the EPDS (Edinburgh Postnatal Depression Scale), the PHQ-9 (Patient Health Questionnaire-9), theNEO-FFI (Personality Inventory), and the BSSS (Berlin Social Support Scales). Probable depression any time during first 3 months postpartum was prevalent among 6.38% of women, based on the following criteria: EPDS > 12 points and PHQ-9 > 9 points. A score of EPDS > 9 in the first week after delivery (ORa = 4.16; CI 1.59-10.86), a history of hospitalisation during pregnancy (ORa = 3.51; CI 1.32-9.20), a high level of neuroticism (ORa = 1.37; CI 1.05-1.77), and high buffering-protective social support (ORa =2.56; 1.25-5.23) were significantly associated with depressive symptoms. Potential protective factors were initial breastfeeding (ORa = 0.31; CI 0.11-0.90) and high satisfaction with currently received social support (ORa=0.41;CI 0.22-0.79). The total dropout rate was 23%. New mothers who are neurotic and who suffered from physical or mental problems during pregnancy and puerperium might experience depressive symptoms more easily. They would also protect those close to them from negative information about themselves. A lack of initial breastfeeding and unsatisfactory social support played a similar role.
Initation of pitting corrosion in martensitic stainless steels. [17-4PH; 13-8Mo; Custom 450
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cieslak, W.R.; Semarge, R.E.; Bovard, F.S.
1986-01-01
The form of localized corrosion known as pitting often initiates preferentially at microstructural inhomogeneities. The pit initiation resistance, therefore, is controlled by the characteristics of the initiation sites, rather than by the bulk material composition. This investigation correlates the pit initiation resistance, as measured by critical pitting potentials, with preferred pit initiation sites for 3 martensitic stainless steels. Pit initiation sites are determined by secondary electron (SE) and backscattered electron (BSE) imaging and energy dispersive and wavelength dispersive spectrometries (EDS and WDS) with a scalling electron microscope (SEM) and an electron probe microanalyzer (EPMA).
Liu, Jason; Lezama, Nicholas; Gasper, Joseph; Kawata, Jennifer; Morley, Sybil; Helmer, Drew; Ciminera, Paul
2016-07-01
The aim of this study was to determine how burn pit emissions exposure is associated with the incidence of respiratory and cardiovascular conditions. We examined the associations between assumed geographic and self-reported burn pit emissions exposure and respiratory and cardiovascular outcomes in participants of the Airborne Hazards and Open Burn Pit Registry. We found significant dose-response associations for higher risk of self-reported emphysema, chronic bronchitis, or chronic obstructive pulmonary disease with increased days of deployment within 2 miles of selected burn pits (P-trend = 0.01) and self-reported burn pit smoke exposure (P-trend = 0.0005). We found associations between burn pit emissions exposure and higher incidence of post-deployment self-reported respiratory and cardiovascular conditions, but these findings should be interpreted with caution because the surrogate measurements of burn pit emissions exposure in this analysis may not reflect individual exposure levels.
Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution
Platz, T.; Schorghofer, N.; Prettyman, T. H.; De Sanctis, M. C.; Crown, D. A.; Schmedemann, N.; Neesemann, A.; Kneissl, T.; Marchi, S.; Schenk, P. M.; Bland, M. T.; Schmidt, B. E.; Hughson, K. H. G.; Tosi, F.; Zambon, F.; Mest, S. C.; Yingst, R. A.; Williams, D. A.; Russell, C. T.; Raymond, C. A.
2017-01-01
Abstract Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice‐rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization. PMID:28989206
Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution.
Sizemore, H G; Platz, T; Schorghofer, N; Prettyman, T H; De Sanctis, M C; Crown, D A; Schmedemann, N; Neesemann, A; Kneissl, T; Marchi, S; Schenk, P M; Bland, M T; Schmidt, B E; Hughson, K H G; Tosi, F; Zambon, F; Mest, S C; Yingst, R A; Williams, D A; Russell, C T; Raymond, C A
2017-07-16
Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.
Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution
Sizemore, H.G.; Platz, Thomas; Schorghofer, Norbert; Prettyman, Thomas; De Sanctis, Maria Christina; Crown, David A.; Schmedemann, Nico; Nessemann, Andeas; Kneissl, Thomas; Simone Marchi,; Schenk, Paul M.; Bland, Michael T.; Schmidt, B.E.; Hughson, Kynan H.G.; Tosi, F.; Zambon, F; Mest, S.C.; Yingst, R.A.; Williams, D.A.; Russell, C.T.; Raymond, C.A.
2017-01-01
Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.
Force-displacement measurements of earlywood bordered pits using a mesomechanical tester.
Zelinka, Samuel L; Bourne, Keith J; Hermanson, John C; Glass, Samuel V; Costa, Adriana; Wiedenhoeft, Alex C
2015-10-01
The elastic properties of pit membranes are reported to have important implications in understanding air-seeding phenomena in gymnosperms, and pit aspiration plays a large role in wood technological applications such as wood drying and preservative treatment. Here we present force-displacement measurements for pit membranes of circular bordered pits, collected on a mesomechanical testing system. The system consists of a quartz microprobe attached to a microforce sensor that is positioned and advanced with a micromanipulator mounted on an inverted microscope. Membrane displacement is measured from digital image analysis. Unaspirated pits from earlywood of never-dried wood of Larix and Pinus and aspirated pits from earlywood of dried wood of Larix were tested to generate force-displacement curves up to the point of membrane failure. Two failure modes were observed: rupture or tearing of the pit membrane by the microprobe tip, and the stretching of the pit membrane until the torus was forced out of the pit chamber through the pit aperture without rupture, a condition we refer to as torus prolapse. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
NASA Astrophysics Data System (ADS)
Hanzel, Jason
The use of lidar (light detection and ranging), a remote sensing tool based on principles of laser optometry, in mapping complex, multi-scale fracture networks had not been rigorously tested prior to this study despite its foreseeable utility in interpreting rock fabric with imprints of complex tectonic evolution. This thesis demonstrates lidar-based characterization of the Woodford Shale where intense fracturing could be due to both tectonism and mineralogy. The study area is the McAlister Shale Pit in south-central Oklahoma where both the upper and middle sections of the Woodford Shale are exposed and can be lidar-mapped. Lidar results are validated using hand-measured strike and dips of fracture planes, thin sections and mineral chemistry of selected samples using X-ray diffraction (XRD). Complexity of the fracture patterns as well as inaccessibility of multiple locations within the shale pit makes hand-measurement prone to errors and biases; lidar provides an opportunity for less biased and more efficient field mapping. Fracture mapping with lidar is a multi-step process. The lidar data are converted from point clouds into a mesh through triangulation. User-defined parameters such as size and orientation of the individual triangular elements are then used to group similar elements into surfaces. The strike and dip attribute of the simulated surfaces are visualized in an equal area lower hemisphere projection stereonet. Three fracture sets were identified in the upper and middle sections with common orientation but substantially different spatial density. Measured surface attributes and spatial density relations from lidar were validated using their hand-measured counterparts. Thin section analysis suggests that high fracture density in the upper Woodford measured by both the lidar and the hand-measured data could be due to high quartz. A significant finding of this study is the reciprocal relation between lidar intensity and gamma-ray (GR), which is generally used to infer outcrop mineralogy. XRD analysis of representative samples along the common profiles show that both GR and lidar intensity were influenced by the same minerals in essentially opposite ways. Results strongly suggest that the lidar cannot only remotely map the geomorphology, but also the relative mineralogical variations to the first order of approximation.
Environmental Report 1993-1996
DOT National Transportation Integrated Search
2002-08-16
These reports are prepared for the U.S. Department of Energy (DOE), as required by DOE Order 5400.1 and DOE Order 231.1, by the Environmental Protection Department (EPD) at the Lawrence Livermore National Laboratory (LLNL). The results of LLNL's envi...
Prevalence and risk factors for postpartum depressive symptoms in Argentina: a cross-sectional study
Mathisen, Siv Elin; Glavin, Kari; Lien, Lars; Lagerløv, Per
2013-01-01
Introduction Postpartum depression is a prevalent disorder with negative consequences for women, infants, and the family as a whole. Most studies of this disorder have been conducted in Western countries, and studies from developing countries are few. In this paper, we report the first – as far as we are aware – study of the prevalence and risk factors associated with postpartum depressive symptoms in Argentina. Materials and methods The study participants were 86 women attending 6 week checkups, (range 4–12 weeks) postpartum at a private health care center in the metropolitan area of Buenos Aires. The women completed the Edinburgh Postnatal Depression Scale (EPDS) and a questionnaire collecting demographic and obstetric data. Data were described as proportions (percentages). Differences between proportions were assessed with chi-squared tests. To control for possible confounders, we fitted bivariate logistic regression models in which the dependent variable was an EPDS sum score of <10 versus a score of ≥10. Results We found a high prevalence of depressive symptoms. A total of 32 women (37.2%) had an EPDS score of ≥10, 16 (18.6%) had a score between 10 and 12, and 16 (18.6%) had a score of ≥13. In our sample, an EPDS score of ≥10 was significantly associated with multiparity (odds ratio [OR] =3.58; 95% confidence interval [CI]: 1.13–11.30; P=0.030), pregnancy complications (OR =3.40; 95% CI: 1.03–11.26; P=0.045), labor complications (OR =11.43; 95% CI: 1.71–76.61; P=0.012), cesarean section (OR =4.19; 95% CI: 1.10–16.01; P=0.036), and incomplete breast-feeding (OR =5.00; 95% CI: 1.42–17.54; P=0.012). Conclusion Our results indicate that postpartum depression may be prevalent in Argentina, and may be associated with incomplete breast-feeding, cesarean section, perinatal complications and multiparity. The prevalence and risk factors for postpartum depression has not been described previously and is a considerable health-related problem among women. Argentinian health professionals should be aware of the high prevalence rate and possible risk factors so that these women and families can be identified and receive adequate support and treatment. PMID:24294009
Giri, Jay; Kennedy, Kevin F; Weinberg, Ido; Hawkins, Beau M; Press, Marcella Calfon; Drachman, Douglas; McCormick, Daniel J; Aronow, Herbert D; White, Christopher J; Rosenfield, Kenneth; Yeh, Robert W
2014-02-01
This study sought to characterize usage and outcomes of carotid stenting platforms. A variety of stents and embolic protection devices (EPDs) are used for carotid artery stenting. Little is known about current usage patterns and differences in outcomes with these devices. We analyzed 12,135 consecutive carotid stent procedures in the NCDR (National Cardiovascular Data Registry) CARE (Carotid Artery Revascularization and Endarterectomy) registry performed between January 1, 2007 and March 31, 2012. We compared baseline characteristics and crude and multivariable-adjusted rates of in-hospital combined death/stroke among patients treated with Acculink/Accunet (Abbott Laboratories, Abbott Park, Illinois), Xact/Emboshield (Abbott), and Precise/Angioguard (Cordis Corporation, Bridgewater, New Jersey) stent/EPD combinations. In 78.2% of cases, stents were used in conjunction with their specific, corresponding U.S. Food and Drug Administration-approved EPD. The Acculink/Accunet (n = 2,617, 21.6%), Xact/Emboshield (n = 3,507, 28.9%), and Precise/Angioguard (n = 2,696, 22.2%) stent/EPD combinations were used in 72.7% of all cases. The Protégé/SpiderFx (ev3 Endovascular Inc., Plymouth, Minnesota) (n = 453, 3.7%) and Wallstent/Filterwire (Boston Scientific, Natick, Massachusetts) (n = 213, 1.8%) devices were used in a minority of cases. In unadjusted analyses, the Precise/Angioguard system was associated with higher rates of the primary outcome than were the Acculink/Accunet (2.5% vs. 1.8%; p = 0.058) and Xact/Emboshield (2.5% vs. 1.9%; p = 0.14) systems that were not statistically different. In adjusted analyses, differences between Precise/Angioguard and Accunet/Acculink (odds ratio [OR]: 1.48, 95% confidence interval [CI]: 0.89 to 2.47; p = 0.065), Precise/Angioguard and Xact/Emboshield (OR: 1.16, 95% CI: 0.77 to 1.76; p = 0.38), and Xact/Emboshield and Accunet/Acculink (OR: 1.28, 95% CI: 0.82 to 1.97; p = 0.18) remained nonsignificant. In modern U.S. practice, the Acculink/Accunet, Xact/Emboshield, and Precise/Angioguard carotid stenting systems are used in most cases and are associated with similarly low rates of adverse events. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Least tern and piping plover nesting at sand pits in Nebraska
Sidle, John G.; Kirsch, E.M.
1993-01-01
Endangered Least Terns (Sterna antillarum) and threatened Piping Plovers (Charadrius melodus) nest at commercial sand and gravel mining operations (sand pits) along the Platte River system in Nebraska. Sandbar habitat has been disappearing since the early 1900's along the Platte River system, but numbers of sand pits have increased. We hypothesized that birds would more fully utilize sand pits where suitable sandbar habitat was limited. We inventoried sand pits and censused terns and plovers on both habitats along the Loup River, part of the North Loup River, and most of the Platte River during 1988-1991. Using aircraft, we also quantified features of suitable sand pits present on the central Platte in 1988 and lower Platte in 1990, and related features to abundance and presence of birds. We found 225 sand pits of which 78 were suitable and 187 were unsuitable for nesting. Along the central Platte, where sandbar habitat is severely degraded, birds nested at 81% of the suitable sand pits (N = 32) at least once during 1988-1991, and most birds (61-94%) nested on sand pits. Along the lower Platte, where both sandbar and sand pit habitat are plentiful, birds nested at 60% of the suitable sand pits (N = 35) at least once during 1988-1991, and most birds (60-86%) nested on sandbars. Numbers of terns and plovers were more weakly correlated with features of sand pits on the central Platte than on the lower Platte. Least Terns and Piping Plovers seem to use more of the suitable sand pit habitat on the central Platte than on the lower Platte. Sand pits probably have influenced the birds' distribution by providing alternative nesting habitat along rivers where suitable sandbars are rare or absent.
NASA Astrophysics Data System (ADS)
Ahmad Bukhary, A. K.; Ruslan, M. Y.; Mohd. Fauzi, M. M.; Nicholas, S.; Muhamad Fahmi, M. H.; Izfa Riza, H.; Idris, A. B.
2015-09-01
A newly innovated and efficient UV-Pit-light Trap is described and the results of the experiments on its efficacy that were carried out within different oil palm age stands of the year 2013 were evaluated and compared with previous study year of 2010, with out the implementation of the UV-Pit-light Trap. In 2013 the UV-Pit-light Traps, the Malaise Traps, and the Pit-fall Traps were employed, while in 2010, the conventional canopy-height UV-Light Traps, Malaise Traps, and the Pit-fall Traps were employed. The UV-Pit-light traps caught more beetle and ant families, morpho-species, and individuals per species compared with the passive Pit-fall traps. The UV-Pit-light Trap targets different subsets of the oil palm beetles and ants' communities, specifying on epigaeic-related micro-habitats, with different oil palm age stands have different compositions of micro-habitats. The UV-Pit-light Traps have the dual quality for satisfying both the biological and statistical data requirements and evaluations. There were no significant difference between the UV-Pit-light Traps and the passive Pit-fall Traps, while the trapping difference with the Malaise traps for different seasons of the year 2013. The UV-Pit-light Traps and the Malaise Traps were complementary to each other, detecting the activities of beetles and ants around the epigaeic-related micro-habitats or having active flight activities respectively according to annual seasons. The UV-Pit-light Trap is an oil-palm specific type of passive trapping system, focusing on the insect species dwelling the upper-ground/epigaeic micro-habitats.
One dimensional Linescan x-ray detection of pits in fresh cherries
USDA-ARS?s Scientific Manuscript database
The presence of pits in processed cherries is a concern for both processors and consumers, in many cases causing injury and potential lawsuits. While machines used for pitting cherries are extremely efficient, if one or more plungers in a pitting head become misaligned, a large number of pits may p...
Large heterogeneities in comet 67P as revealed by active pits from sinkhole collapse.
Vincent, Jean-Baptiste; Bodewits, Dennis; Besse, Sébastien; Sierks, Holger; Barbieri, Cesare; Lamy, Philippe; Rodrigo, Rafael; Koschny, Detlef; Rickman, Hans; Keller, Horst Uwe; Agarwal, Jessica; A'Hearn, Michael F; Auger, Anne-Thérèse; Barucci, M Antonella; Bertaux, Jean-Loup; Bertini, Ivano; Capanna, Claire; Cremonese, Gabriele; Da Deppo, Vania; Davidsson, Björn; Debei, Stefano; De Cecco, Mariolino; El-Maarry, Mohamed Ramy; Ferri, Francesca; Fornasier, Sonia; Fulle, Marco; Gaskell, Robert; Giacomini, Lorenza; Groussin, Olivier; Guilbert-Lepoutre, Aurélie; Gutierrez-Marques, P; Gutiérrez, Pedro J; Güttler, Carsten; Hoekzema, Nick; Höfner, Sebastian; Hviid, Stubbe F; Ip, Wing-Huen; Jorda, Laurent; Knollenberg, Jörg; Kovacs, Gabor; Kramm, Rainer; Kührt, Ekkehard; Küppers, Michael; La Forgia, Fiorangela; Lara, Luisa M; Lazzarin, Monica; Lee, Vicky; Leyrat, Cédric; Lin, Zhong-Yi; Lopez Moreno, Josè J; Lowry, Stephen; Magrin, Sara; Maquet, Lucie; Marchi, Simone; Marzari, Francesco; Massironi, Matteo; Michalik, Harald; Moissl, Richard; Mottola, Stefano; Naletto, Giampiero; Oklay, Nilda; Pajola, Maurizio; Preusker, Frank; Scholten, Frank; Thomas, Nicolas; Toth, Imre; Tubiana, Cecilia
2015-07-02
Pits have been observed on many cometary nuclei mapped by spacecraft. It has been argued that cometary pits are a signature of endogenic activity, rather than impact craters such as those on planetary and asteroid surfaces. Impact experiments and models cannot reproduce the shapes of most of the observed cometary pits, and the predicted collision rates imply that few of the pits are related to impacts. Alternative mechanisms like explosive activity have been suggested, but the driving process remains unknown. Here we report that pits on comet 67P/Churyumov-Gerasimenko are active, and probably created by a sinkhole process, possibly accompanied by outbursts. We argue that after formation, pits expand slowly in diameter, owing to sublimation-driven retreat of the walls. Therefore, pits characterize how eroded the surface is: a fresh cometary surface will have a ragged structure with many pits, while an evolved surface will look smoother. The size and spatial distribution of pits imply that large heterogeneities exist in the physical, structural or compositional properties of the first few hundred metres below the current nucleus surface.
Light scattering from laser induced pit ensembles on high power laser optics
Feigenbaum, Eyal; Elhadj, Selim; Matthews, Manyalibo J.
2015-01-01
Far-field light scattering characteristics from randomly arranged shallow Gaussian-like shaped laser induced pits, found on optics exposed to high energy laser pulses, is studied. Closed-form expressions for the far-field intensity distribution and scattered power are derived for individual pits and validated using numerical calculations of both Fourier optics and FDTD solutions to Maxwell’s equations. It is found that the scattered power is proportional to the square of the pit width and approximately also to the square of the pit depth, with the proportionality factor scaling with pit depth. As a result, the power scattered from shallow pitted optics is expectedmore » to be substantially lower than assuming complete scattering from the total visible footprint of the pits.« less
Yang, Zixuan; Kan, Bo; Li, Jinxu; Qiao, Lijie; Volinsky, Alex A; Su, Yanjing
2017-11-14
Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test results revealed that hydrostatic pressure can increase metastable pitting formation frequency and promote stabilization of metastable pitting growth. Electrochemical impedance spectroscopy (EIS) results indicate that Hydrostatic pressure decreases the charge transfer resistance and increases the dissolution rate within the cavities. Corrosion test results also indicated that pitting initiation and propagation are accelerated by hydrostatic pressure. Result validity was verified by evaluating metastable pitting to predict pitting corrosion resistance.
Yang, Zixuan; Kan, Bo; Li, Jinxu; Su, Yanjing; Qiao, Lijie; Volinsky, Alex A.
2017-01-01
Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test results revealed that hydrostatic pressure can increase metastable pitting formation frequency and promote stabilization of metastable pitting growth. Electrochemical impedance spectroscopy (EIS) results indicate that Hydrostatic pressure decreases the charge transfer resistance and increases the dissolution rate within the cavities. Corrosion test results also indicated that pitting initiation and propagation are accelerated by hydrostatic pressure. Result validity was verified by evaluating metastable pitting to predict pitting corrosion resistance. PMID:29135912
The Effects of Hot Corrosion Pits on the Fatigue Resistance of a Disk Superalloy
NASA Technical Reports Server (NTRS)
Gabb, Timothy P.; Telesman, Jack; Hazel, Brian; Mourer, David P.
2009-01-01
The effects of hot corrosion pits on low cycle fatigue life and failure modes of the disk superalloy ME3 were investigated. Low cycle fatigue specimens were subjected to hot corrosion exposures producing pits, then tested at low and high temperatures. Fatigue lives and failure initiation points were compared to those of specimens without corrosion pits. Several tests were interrupted to estimate the fraction of fatigue life that fatigue cracks initiated at pits. Corrosion pits significantly reduced fatigue life by 60 to 98 percent. Fatigue cracks initiated at a very small fraction of life for high temperature tests, but initiated at higher fractions in tests at low temperature. Critical pit sizes required to promote fatigue cracking were estimated, based on measurements of pits initiating cracks on fracture surfaces.