Properties of nano-structured Ni/YSZ anodes fabricated from plasma sprayable NiO/YSZ powder prepared by single step solution combustion method

Energy Technology Data Exchange (ETDEWEB)

Prakash, B. Shri; Balaji, N.; Kumar, S. Senthil; Aruna, S.T., E-mail: staruna194@gmail.com

2016-12-15

Highlights: • Preparation of plasma grade NiO/YSZ powder in single step. • Fabrication of nano-structured Ni/YSZ coating. • Conductivity of 600 S/cm at 800 °C. - Abstract: NiO/YSZ anode coatings are fabricated by atmospheric plasma spraying at different plasma powers from plasma grade NiO/YSZ powders that are prepared in a single step by solution combustion method. The process adopted is devoid of multi-steps that are generally involved in conventional spray drying or fusing and crushing methods. Density of the coating increased and porosity decreased with increase in the plasma power of deposition. An ideal nano-structured Ni/YSZ anode encompassing nano YSZ particles, nano Ni particles and nano pores is achieved on reducing the coating deposited at lower plasma powers. The coating exhibit porosities in the range of 27%, sufficient for anode functional layers. Electronic conductivity of the coatings is in the range of 600 S/cm at 800 °C.

Percutaneous Cystgastrostomy as a Single-Step Procedure

International Nuclear Information System (INIS)

Curry, L.; Sookur, P.; Low, D.; Bhattacharya, S.; Fotheringham, T.

2009-01-01

The purpose of this study was to evaluate the success of percutaneous transgastric cystgastrostomy as a single-step procedure. We performed a retrospective analysis of single-step percutaneous transgastric cystgastrostomy carried out in 12 patients (8 male, 4 female; mean age 44 years; range 21-70 years), between 2002 and 2007, with large symptomatic pancreatic pseudocysts for whom up to 1-year follow-up data (mean 10 months) were available. All pseudocysts were drained by single-step percutaneous cystgastrostomy with the placement of either one or two stents. The procedure was completed successfully in all 12 patients. The pseudocysts showed complete resolution on further imaging in 7 of 12 patients with either enteric passage of the stent or stent removal by endoscopy. In 2 of 12 patients, the pseudocysts showed complete resolution on imaging, with the stents still noted in situ. In 2 of 12 patients, the pseudocysts became infected after 1 month and required surgical intervention. In 1 of 12 patients, the pseudocyst showed partial resolution on imaging, but subsequently reaccumulated and later required external drainage. In our experience, percutaneous cystgastrostomy as a single-step procedure has a high success rate and good short-term outcomes over 1-year follow-up and should be considered in the treatment of large symptomatic cysts.

General methods for analysis of sequential "n-step" kinetic mechanisms: application to single turnover kinetics of helicase-catalyzed DNA unwinding.

Science.gov (United States)

Lucius, Aaron L; Maluf, Nasib K; Fischer, Christopher J; Lohman, Timothy M

2003-10-01

Helicase-catalyzed DNA unwinding is often studied using "all or none" assays that detect only the final product of fully unwound DNA. Even using these assays, quantitative analysis of DNA unwinding time courses for DNA duplexes of different lengths, L, using "n-step" sequential mechanisms, can reveal information about the number of intermediates in the unwinding reaction and the "kinetic step size", m, defined as the average number of basepairs unwound between two successive rate limiting steps in the unwinding cycle. Simultaneous nonlinear least-squares analysis using "n-step" sequential mechanisms has previously been limited by an inability to float the number of "unwinding steps", n, and m, in the fitting algorithm. Here we discuss the behavior of single turnover DNA unwinding time courses and describe novel methods for nonlinear least-squares analysis that overcome these problems. Analytic expressions for the time courses, f(ss)(t), when obtainable, can be written using gamma and incomplete gamma functions. When analytic expressions are not obtainable, the numerical solution of the inverse Laplace transform can be used to obtain f(ss)(t). Both methods allow n and m to be continuous fitting parameters. These approaches are generally applicable to enzymes that translocate along a lattice or require repetition of a series of steps before product formation.

Comparative analysis of single-step and two-step biodiesel production using supercritical methanol on laboratory-scale

International Nuclear Information System (INIS)

Micic, Radoslav D.; Tomić, Milan D.; Kiss, Ferenc E.; Martinovic, Ferenc L.; Simikić, Mirko Ð.; Molnar, Tibor T.

2016-01-01

Highlights: • Single-step supercritical transesterification compared to the two-step process. • Two-step process: oil hydrolysis and subsequent supercritical methyl esterification. • Experiments were conducted in a laboratory-scale batch reactor. • Higher biodiesel yields in two-step process at milder reaction conditions. • Two-step process has potential to be cost-competitive with the single-step process. - Abstract: Single-step supercritical transesterification and two-step biodiesel production process consisting of oil hydrolysis and subsequent supercritical methyl esterification were studied and compared. For this purpose, comparative experiments were conducted in a laboratory-scale batch reactor and optimal reaction conditions (temperature, pressure, molar ratio and time) were determined. Results indicate that in comparison to a single-step transesterification, methyl esterification (second step of the two-step process) produces higher biodiesel yields (95 wt% vs. 91 wt%) at lower temperatures (270 °C vs. 350 °C), pressures (8 MPa vs. 12 MPa) and methanol to oil molar ratios (1:20 vs. 1:42). This can be explained by the fact that the reaction system consisting of free fatty acid (FFA) and methanol achieves supercritical condition at milder reaction conditions. Furthermore, the dissolved FFA increases the acidity of supercritical methanol and acts as an acid catalyst that increases the reaction rate. There is a direct correlation between FFA content of the product obtained in hydrolysis and biodiesel yields in methyl esterification. Therefore, the reaction parameters of hydrolysis were optimized to yield the highest FFA content at 12 MPa, 250 °C and 1:20 oil to water molar ratio. Results of direct material and energy costs comparison suggest that the process based on the two-step reaction has the potential to be cost-competitive with the process based on single-step supercritical transesterification. Higher biodiesel yields, similar or lower energy

Towards single step production of multi-layer inorganic hollow fibers

NARCIS (Netherlands)

de Jong, J.; Benes, Nieck Edwin; Koops, G.H.; Wessling, Matthias

2004-01-01

In this work we propose a generic synthesis route for the single step production of multi-layer inorganic hollow fibers, based on polymer wet spinning combined with a heat treatment. With this new method, membranes with a high surface area per unit volume ratio can be produced, while production time

Genomic prediction in a nuclear population of layers using single-step models.

Science.gov (United States)

Yan, Yiyuan; Wu, Guiqin; Liu, Aiqiao; Sun, Congjiao; Han, Wenpeng; Li, Guangqi; Yang, Ning

2018-02-01

Single-step genomic prediction method has been proposed to improve the accuracy of genomic prediction by incorporating information of both genotyped and ungenotyped animals. The objective of this study is to compare the prediction performance of single-step model with a 2-step models and the pedigree-based models in a nuclear population of layers. A total of 1,344 chickens across 4 generations were genotyped by a 600 K SNP chip. Four traits were analyzed, i.e., body weight at 28 wk (BW28), egg weight at 28 wk (EW28), laying rate at 38 wk (LR38), and Haugh unit at 36 wk (HU36). In predicting offsprings, individuals from generation 1 to 3 were used as training data and females from generation 4 were used as validation set. The accuracies of predicted breeding values by pedigree BLUP (PBLUP), genomic BLUP (GBLUP), SSGBLUP and single-step blending (SSBlending) were compared for both genotyped and ungenotyped individuals. For genotyped females, GBLUP performed no better than PBLUP because of the small size of training data, while the 2 single-step models predicted more accurately than the PBLUP model. The average predictive ability of SSGBLUP and SSBlending were 16.0% and 10.8% higher than the PBLUP model across traits, respectively. Furthermore, the predictive abilities for ungenotyped individuals were also enhanced. The average improvements of prediction abilities were 5.9% and 1.5% for SSGBLUP and SSBlending model, respectively. It was concluded that single-step models, especially the SSGBLUP model, can yield more accurate prediction of genetic merits and are preferable for practical implementation of genomic selection in layers. © 2017 Poultry Science Association Inc.

A novel single-step synthesis of N-doped TiO2 via a sonochemical method

International Nuclear Information System (INIS)

Wang, Xi-Kui; Wang, Chen; Guo, Wei-Lin; Wang, Jin-Gang

2011-01-01

Graphical abstract: The N-doped anatase TiO 2 nanoparticles were synthesized by sonochemical method. The as-prepared sample is characterized by XRD, TEM, XPS and UV-Vis DRS. The photocatalytic activity of the photocatalyst was evaluated by the photodegradation of an azo dye direct sky blue 5B. Highlights: → A novel singal-step sonochemical synthesis method for the preparation of anatase N-doped TiO 2 nanocrystalline at low temperature has been devoleped. → The as-prepared sample is characterized by XRD, TEM, XPS and UV-Vis DRS. → The photodegradation of azo dye direct sky blue 5 showed that the N-doped TiO 2 catalyst is of high visible-light photocatalytic activity. -- Abstract: A novel single-step synthetic method for the preparation of anatase N-doped TiO 2 nanocrystalline at low temperature has been devoleped. The N-doped anatase TiO 2 nanoparticles were synthesized by sonication of the solution of tetraisopropyl titanium and urea in water and isopropyl alcohol at 80 o C for 150 min. The as-prepared sample was characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-vis absorption spectrum. The product structure depends on the reaction temperature and reaction time. The photocatalytic activity of the as-prepared photocatalyst was evaluated via the photodegradation of an azo dye direct sky blue 5B. The results show that the N-doped TiO 2 nanocrystalline prepared via sonication exhibit an excellent photocatalytic activity under UV light and simulated sunlight.

Comparison of single-step and two-step purified coagulants from Moringa oleifera seed for turbidity and DOC removal.

Science.gov (United States)

Sánchez-Martín, J; Ghebremichael, K; Beltrán-Heredia, J

2010-08-01

The coagulant proteins from Moringa oleifera purified with single-step and two-step ion-exchange processes were used for the coagulation of surface water from Meuse river in The Netherlands. The performances of the two purified coagulants and the crude extract were assessed in terms of turbidity and DOC removal. The results indicated that the optimum dosage of the single-step purified coagulant was more than two times higher compared to the two-step purified coagulant in terms of turbidity removal. And the residual DOC in the two-step purified coagulant was lower than in single-step purified coagulant or crude extract. (c) 2010 Elsevier Ltd. All rights reserved.

Improving genetic evaluation of litter size and piglet mortality for both genotyped and nongenotyped individuals using a single-step method.

Science.gov (United States)

Guo, X; Christensen, O F; Ostersen, T; Wang, Y; Lund, M S; Su, G

2015-02-01

A single-step method allows genetic evaluation using information of phenotypes, pedigree, and markers from genotyped and nongenotyped individuals simultaneously. This paper compared genomic predictions obtained from a single-step BLUP (SSBLUP) method, a genomic BLUP (GBLUP) method, a selection index blending (SELIND) method, and a traditional pedigree-based method (BLUP) for total number of piglets born (TNB), litter size at d 5 after birth (LS5), and mortality rate before d 5 (Mort; including stillbirth) in Danish Landrace and Yorkshire pigs. Data sets of 778,095 litters from 309,362 Landrace sows and 472,001 litters from 190,760 Yorkshire sows were used for the analysis. There were 332,795 Landrace and 207,255 Yorkshire animals in the pedigree data, among which 3,445 Landrace pigs (1,366 boars and 2,079 sows) and 3,372 Yorkshire pigs (1,241 boars and 2,131 sows) were genotyped with the Illumina PorcineSNP60 BeadChip. The results showed that the 3 methods with marker information (SSBLUP, GBLUP, and SELIND) produced more accurate predictions for genotyped animals than the pedigree-based method. For genotyped animals, the average of reliabilities for all traits in both breeds using traditional BLUP was 0.091, which increased to 0.171 w+hen using GBLUP and to 0.179 when using SELIND and further increased to 0.209 when using SSBLUP. Furthermore, the average reliability of EBV for nongenotyped animals was increased from 0.091 for traditional BLUP to 0.105 for the SSBLUP. The results indicate that the SSBLUP is a good approach to practical genomic prediction of litter size and piglet mortality in Danish Landrace and Yorkshire populations.

Single step fabrication method of fullerene/TiO2 composite photocatalyst for hydrogen production

International Nuclear Information System (INIS)

Kum, Jong Min; Cho, Sung Oh

2011-01-01

Hydrogen is one of the most promising alternative energy sources. Fossil fuel, which is the most widely used energy source, has two defects. One is CO 2 emission causing global warming. The other is exhaustion. On the other hand, hydrogen emits no CO 2 and can be produced by splitting water which is renewable and easily obtainable source. However, about 95% of hydrogen is derived from fossil fuel. It limits the merits of hydrogen. Hydrogen from fossil fuel is not a renewable energy anymore. To maximize the merits of hydrogen, renewability and no CO 2 emission, unconventional hydrogen production methods without using fossil fuel are required. Photocatalytic water-splitting is one of the unconventional hydrogen production methods. Photocatalytic water-splitting that uses hole/electron pairs of semiconductor is expectable way to produce clean and renewable hydrogen from solar energy. TiO 2 is the semiconductor material which has been most widely used as photocatalyst. TiO 2 shows high photocatalytic reactivity and stability in water. However, its wide band gap only absorbs UV light which is only 5% of sun light. To enhance the visible light responsibility, composition with fullerene based materials has been investigated. 1-2 Methano-fullerene carboxylic acid (FCA) is one of the fullerene based materials. We tried to fabricate FCA/TiO 2 composite using UV assisted single step method. The method not only simplified the fabrication procedures, but enhanced hydrogen production rate

The stepping behavior analysis of pedestrians from different age groups via a single-file experiment

Science.gov (United States)

Cao, Shuchao; Zhang, Jun; Song, Weiguo; Shi, Chang'an; Zhang, Ruifang

2018-03-01

The stepping behavior of pedestrians with different age compositions in single-file experiment is investigated in this paper. The relation between step length, step width and stepping time are analyzed by using the step measurement method based on the calculation of curvature of the trajectory. The relations of velocity-step width, velocity-step length and velocity-stepping time for different age groups are discussed and compared with previous studies. Finally effects of pedestrian gender and height on stepping laws and fundamental diagrams are analyzed. The study is helpful for understanding pedestrian dynamics of movement. Meanwhile, it offers experimental data to develop a microscopic model of pedestrian movement by considering stepping behavior.

Comparison of single-entry and double-entry two-step couple screening for cystic fibrosis carriers

NARCIS (Netherlands)

tenKate, LP; Verheij, JBGM; Wildhagen, MF; Hilderink, HBM; Kooij, L; Verzijl, JG; Habbema, JDF

1996-01-01

Both single-entry two-step (SETS) couple screening and double-entry two-step (DETS) couple screening have been recommended as methods to screen for cystic fibrosis gene carriers. In this paper we compare the expected results from both types of screening. In general, DETS results in a higher

AN EFFICIENT ANALYSIS FOR ABSORPTION AND GAIN COEFFICIENTS IN 'SINGLE STEP-INDEX WAVEGUIDE'S BY USING THE ALPHA METHOD

Directory of Open Access Journals (Sweden)

Mustafa TEMİZ

2008-02-01

Full Text Available In this study, some design parameters such as normalized frequency and especially normalized propagation constant have been obtained, depending on some parameters which are functions of energy eigenvalues of the carriers such as electrons and holes confined in a single step-index waveguide laser (SSIWGL or single stepindex waveguide (SSIWG. Some optical expressions about the optical power and probability quantities for the active region and cladding layers of the SSIWG or SSIWGL have been investigated. Investigations have been undertaken in terms of these parameters and also individually the optical even and odd electric field waves with the lowest-modes were theoretically computed. Especially absorption coefficients and loss coefficients addition to some important quantities of the single step-index waveguide lasers for the even and odd electric field waves are evaluated.

Comparison of 10 single and stepped methods to identify frail older persons in primary care: diagnostic and prognostic accuracy.

Science.gov (United States)

Sutorius, Fleur L; Hoogendijk, Emiel O; Prins, Bernard A H; van Hout, Hein P J

2016-08-03

Many instruments have been developed to identify frail older adults in primary care. A direct comparison of the accuracy and prevalence of identification methods is rare and most studies ignore the stepped selection typically employed in routine care practice. Also it is unclear whether the various methods select persons with different characteristics. We aimed to estimate the accuracy of 10 single and stepped methods to identify frailty in older adults and to predict adverse health outcomes. In addition, the methods were compared on their prevalence of the identified frail persons and on the characteristics of persons identified. The Groningen Frailty Indicator (GFI), the PRISMA-7, polypharmacy, the clinical judgment of the general practitioner (GP), the self-rated health of the older adult, the Edmonton Frail Scale (EFS), the Identification Seniors At Risk Primary Care (ISAR PC), the Frailty Index (FI), the InterRAI screener and gait speed were compared to three measures: two reference standards (the clinical judgment of a multidisciplinary expert panel and Fried's frailty criteria) and 6-years mortality or long term care admission. Data were used from the Dutch Identification of Frail Elderly Study, consisting of 102 people aged 65 and over from a primary care practice in Amsterdam. Frail older adults were oversampled. The accuracy of each instrument and several stepped strategies was estimated by calculating the area under the ROC-curve. Prevalence rates of frailty ranged from 14.8 to 52.9 %. The accuracy for recommended cut off values ranged from poor (AUC = 0.556 ISAR-PC) to good (AUC = 0.865 gait speed). PRISMA-7 performed best over two reference standards, GP predicted adversities best. Stepped strategies resulted in lower prevalence rates and accuracy. Persons selected by the different instruments varied greatly in age, IADL dependency, receiving homecare and mood. We found huge differences between methods to identify frail persons in prevalence

A facile one-step fluorescence method for the quantitation of low-content single base deamination impurity in synthetic oligonucleotides.

Science.gov (United States)

Su, Xiaoye; Liang, Ruiting; Stolee, Jessica A

2018-06-05

Oligonucleotides are being researched and developed as potential drug candidates for the treatment of a broad spectrum of diseases. The characterization of antisense oligonucleotide (ASO) impurities caused by base mutations (e.g. deamination) which are closely related to the target ASO is a significant analytical challenge. Herein, we describe a novel one-step method, utilizing a strategy that combines fluorescence-ON detection with competitive hybridization, to achieve single base mutation quantitation in extensively modified synthetic ASOs. Given that this method is highly specific and sensitive (LoQ = 4 nM), we envision that it will find utility for screening other impurities as well as sequencing modified oligonucleotides. Copyright © 2018 Elsevier B.V. All rights reserved.

Site-selective substitutional doping with atomic precision on stepped Al (111) surface by single-atom manipulation.

Science.gov (United States)

Chen, Chang; Zhang, Jinhu; Dong, Guofeng; Shao, Hezhu; Ning, Bo-Yuan; Zhao, Li; Ning, Xi-Jing; Zhuang, Jun

2014-01-01

In fabrication of nano- and quantum devices, it is sometimes critical to position individual dopants at certain sites precisely to obtain the specific or enhanced functionalities. With first-principles simulations, we propose a method for substitutional doping of individual atom at a certain position on a stepped metal surface by single-atom manipulation. A selected atom at the step of Al (111) surface could be extracted vertically with an Al trimer-apex tip, and then the dopant atom will be positioned to this site. The details of the entire process including potential energy curves are given, which suggests the reliability of the proposed single-atom doping method.

Single-step link of the superdeformed band in 143Eu

International Nuclear Information System (INIS)

Atac, A.; Bergstroem, M.H.; Nyberg, J.; Persson, J.; Herskind, B.; Joss, D.T.; Lipoglavsek, M.; Tucek, K.

1996-01-01

A discrete γ-ray ransition with an energy of 3360.6 keV deexciting the second lowest SD state in 143 Eu has been discovered. It carries 3.2 % of the full intensity of the band and feeds into a nearly spherical state which is above the I = 35/2 (+) , E x =4947 keV level. The exact placement of the single-step link is, however, not established due to the specially complicated level scheme in the region of interest. The energy of the single-step link agrees well with the previously determined two-step links. (orig.)

Valve cam design using numerical step-by-step method

OpenAIRE

Vasilyev, Aleksandr; Bakhracheva, Yuliya; Kabore, Ousman; Zelenskiy, Yuriy

2014-01-01

This article studies the numerical step-by-step method of cam profile design. The results of the study are used for designing the internal combustion engine valve gear. This method allows to profile the peak efficiency of cams in view of many restrictions, connected with valve gear serviceability and reliability.

Single-step fabrication of quantum funnels via centrifugal colloidal casting of nanoparticle films

Science.gov (United States)

Kim, Jin Young; Adinolfi, Valerio; Sutherland, Brandon R.; Voznyy, Oleksandr; Kwon, S. Joon; Kim, Tae Wu; Kim, Jeongho; Ihee, Hyotcherl; Kemp, Kyle; Adachi, Michael; Yuan, Mingjian; Kramer, Illan; Zhitomirsky, David; Hoogland, Sjoerd; Sargent, Edward H.

2015-01-01

Centrifugal casting of composites and ceramics has been widely employed to improve the mechanical and thermal properties of functional materials. This powerful method has yet to be deployed in the context of nanoparticles—yet size–effect tuning of quantum dots is among their most distinctive and application-relevant features. Here we report the first gradient nanoparticle films to be constructed in a single step. By creating a stable colloid of nanoparticles that are capped with electronic-conduction-compatible ligands we were able to leverage centrifugal casting for thin-films devices. This new method, termed centrifugal colloidal casting, is demonstrated to form films in a bandgap-ordered manner with efficient carrier funnelling towards the lowest energy layer. We constructed the first quantum-gradient photodiode to be formed in a single deposition step and, as a result of the gradient-enhanced electric field, experimentally measured the highest normalized detectivity of any colloidal quantum dot photodetector. PMID:26165185

Single-step fabrication of quantum funnels via centrifugal colloidal casting of nanoparticle films.

KAUST Repository

Kim, Jin Young; Adinolfi, Valerio; Sutherland, Brandon R; Voznyy, Oleksandr; Kwon, S Joon; Kim, Tae Wu; Kim, Jeongho; Ihee, Hyotcherl; Kemp, Kyle; Adachi, Michael; Yuan, Mingjian; Kramer, Illan; Zhitomirsky, David; Hoogland, Sjoerd; Sargent, Edward H

2015-01-01

Centrifugal casting of composites and ceramics has been widely employed to improve the mechanical and thermal properties of functional materials. This powerful method has yet to be deployed in the context of nanoparticles--yet size-effect tuning of quantum dots is among their most distinctive and application-relevant features. Here we report the first gradient nanoparticle films to be constructed in a single step. By creating a stable colloid of nanoparticles that are capped with electronic-conduction-compatible ligands we were able to leverage centrifugal casting for thin-films devices. This new method, termed centrifugal colloidal casting, is demonstrated to form films in a bandgap-ordered manner with efficient carrier funnelling towards the lowest energy layer. We constructed the first quantum-gradient photodiode to be formed in a single deposition step and, as a result of the gradient-enhanced electric field, experimentally measured the highest normalized detectivity of any colloidal quantum dot photodetector.

Single-step fabrication of quantum funnels via centrifugal colloidal casting of nanoparticle films.

KAUST Repository

Kim, Jin Young

2015-07-13

Centrifugal casting of composites and ceramics has been widely employed to improve the mechanical and thermal properties of functional materials. This powerful method has yet to be deployed in the context of nanoparticles--yet size-effect tuning of quantum dots is among their most distinctive and application-relevant features. Here we report the first gradient nanoparticle films to be constructed in a single step. By creating a stable colloid of nanoparticles that are capped with electronic-conduction-compatible ligands we were able to leverage centrifugal casting for thin-films devices. This new method, termed centrifugal colloidal casting, is demonstrated to form films in a bandgap-ordered manner with efficient carrier funnelling towards the lowest energy layer. We constructed the first quantum-gradient photodiode to be formed in a single deposition step and, as a result of the gradient-enhanced electric field, experimentally measured the highest normalized detectivity of any colloidal quantum dot photodetector.

Step-to-step spatiotemporal variables and ground reaction forces of intra-individual fastest sprinting in a single session.

Science.gov (United States)

Nagahara, Ryu; Mizutani, Mirai; Matsuo, Akifumi; Kanehisa, Hiroaki; Fukunaga, Tetsuo

2018-06-01

We aimed to investigate the step-to-step spatiotemporal variables and ground reaction forces during the acceleration phase for characterising intra-individual fastest sprinting within a single session. Step-to-step spatiotemporal variables and ground reaction forces produced by 15 male athletes were measured over a 50-m distance during repeated (three to five) 60-m sprints using a long force platform system. Differences in measured variables between the fastest and slowest trials were examined at each step until the 22nd step using a magnitude-based inferences approach. There were possibly-most likely higher running speed and step frequency (2nd to 22nd steps) and shorter support time (all steps) in the fastest trial than in the slowest trial. Moreover, for the fastest trial there were likely-very likely greater mean propulsive force during the initial four steps and possibly-very likely larger mean net anterior-posterior force until the 17th step. The current results demonstrate that better sprinting performance within a single session is probably achieved by 1) a high step frequency (except the initial step) with short support time at all steps, 2) exerting a greater mean propulsive force during initial acceleration, and 3) producing a greater mean net anterior-posterior force during initial and middle acceleration.

Out of the picture: a study of family drawings by children from step-, single-parent, and non-step families.

Science.gov (United States)

Dunn, Judy; O'Connor, Thomas G; Levy, Irit

2002-12-01

Investigated the family drawings of 180 children ages 5 to 7 years in various family settings, including stepfather, single-parent, complex stepfamilies, and 2-parent control families. The relations of family type and biological relatedness to omission of family members and grouping of parents were examined. Children from step- and single-parent families were more likely to exclude family members than children from "control" non-step families, and exclusion was predicted from biological relatedness. Children who were biologically related to both resident parents were also more likely to group their parents together. Omission of family members was found to be associated with children's adjustment (specifically more externalizing and internalizing behavior) as reported by teachers and parents. The results indicate that biological relatedness is a salient aspect of very young children's representations of their families. The association between adjustment and exclusion of family members and grouping of parents indicates that family drawings may be useful research and clinical tools, when used in combination with other methods of assessment.

Composition of single-step media used for human embryo culture.

Science.gov (United States)

Morbeck, Dean E; Baumann, Nikola A; Oglesbee, Devin

2017-04-01

To determine compositions of commercial single-step culture media and test with a murine model whether differences in composition are biologically relevant. Experimental laboratory study. University-based laboratory. Inbred female mice were superovulated and mated with outbred male mice. Amino acid, organic acid, and ions content were determined for single-step culture media: CSC, Global, G-TL, and 1-Step. To determine whether differences in composition of these media are biologically relevant, mouse one-cell embryos were cultured for 96 hours in each culture media at 5% and 20% oxygen in a time-lapse incubator. Compositions of four culture media were analyzed for concentrations of 30 amino acids, organic acids, and ions. Blastocysts at 96 hours of culture and cell cycle timings were calculated, and experiments were repeated in triplicate. Of the more than 30 analytes, concentrations of glucose, lactate, pyruvate, amino acids, phosphate, calcium, and magnesium varied in concentrations. Mouse embryos were differentially affected by oxygen in G-TL and 1-Step. Four single-step culture media have compositions that vary notably in pyruvate, lactate, and amino acids. Blastocyst development was affected by culture media and its interaction with oxygen concentration. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

An evaluation of a single-step extraction chromatography separation method for Sm-Nd isotope analysis of micro-samples of silicate rocks by high-sensitivity thermal ionization mass spectrometry

International Nuclear Information System (INIS)

Li Chaofeng; Li Xianhua; Li Qiuli; Guo Jinghui; Li Xianghui; Liu Tao

2011-01-01

Graphical abstract: Distribution curve of all eluting fractions for a BCR-2 (1-2-3.5-7 mg) on LN column using HCl and HF as eluting reagent. Highlights: → This analytical protocol affords a simple and rapid analysis for Sm and Nd isotope in minor rock samples. → The single-step separation method exhibits satisfactory separation effect for complex silicate samples. → Corrected 143 Nd/ 144 Nd data show excellent accuracy even if the 140 Ce 16 O + / 144 Nd 16 O + ratio reached to 0.03. - Abstract: A single-step separation scheme is presented for Sm-Nd radiogenic isotope system on very small samples (1-3 mg) of silicate rock. This method is based on Eichrom LN Spec chromatographic material and affords a straightforward separation of Sm-Nd from complex matrix with good purity and satisfactory blank levels, suitable for thermal ionization mass spectrometry (TIMS). This technique, characterized by high efficiency (single-step Sm-Nd separation) and high sensitivity (TIMS on NdO + ion beam), is able to process rapidly (3-4 h), with low procedure blanks ( 143 Nd/ 144 Nd ratios and Sm-Nd concentrations are presented for eleven international silicate rock reference materials, spanning a wide range of Sm-Nd contents and bulk compositions. The analytical results show a good agreement with recommended values within ±0.004% for the 143 Nd/ 144 Nd isotopic ratio and ±2% for Sm-Nd quantification at the 95% confidence level. It is noted that the uncertainty of this method is about 3 times larger than typical precision achievable with two-stage full separation followed by state-of-the-art conventional TIMS using Nd + ion beams which require much larger amounts of Nd. Hence, our single-step separation followed by NdO + ion beam technique is preferred to the analysis for microsamples.

Development of a Single-Step Subtraction Method for Eukaryotic 18S and 28S Ribonucleic Acids

Directory of Open Access Journals (Sweden)

Marie J. Archer

2011-01-01

Full Text Available The abundance of mammalian 18S and 28S ribosomal RNA can decrease the detection sensitivity of bacterial or viral targets in complex host-pathogen mixtures. A method to capture human RNA in a single step was developed and characterized to address this issue. For this purpose, capture probes were covalently attached to magnetic microbeads using a dendrimer linker and the solid phase was tested using rat thymus RNA (mammalian components with Escherichia coli RNA (bacterial target as a model system. Our results indicated that random capture probes demonstrated better performance than specific ones presumably by increasing the number of possible binding sites, and the use of a tetrame-thylammonium-chloride (TMA-Cl- based buffer for the hybridization showed a beneficial effect in the selectivity. The subtraction efficiency determined through real-time RT-PCR revealed capture-efficiencies comparable with commercially available enrichment kits. The performance of the solid phase can be further fine tuned by modifying the annealing time and temperature.

The Point Zoro Symmetric Single-Step Procedure for Simultaneous Estimation of Polynomial Zeros

Directory of Open Access Journals (Sweden)

Mansor Monsi

2012-01-01

Full Text Available The point symmetric single step procedure PSS1 has R-order of convergence at least 3. This procedure is modified by adding another single-step, which is the third step in PSS1. This modified procedure is called the point zoro symmetric single-step PZSS1. It is proven that the R-order of convergence of PZSS1 is at least 4 which is higher than the R-order of convergence of PT1, PS1, and PSS1. Hence, computational time is reduced since this procedure is more efficient for bounding simple zeros simultaneously.

Method for manufacturing a single crystal nanowire

NARCIS (Netherlands)

van den Berg, Albert; Bomer, Johan G.; Carlen, Edwin; Chen, S.; Kraaijenhagen, Roderik Adriaan; Pinedo, Herbert Michael

2013-01-01

A method for manufacturing a single crystal nano-structure is provided comprising the steps of providing a device layer with a 100 structure on a substrate; providing a stress layer onto the device layer; patterning the stress layer along the 110 direction of the device layer; selectively removing

Method for manufacturing a single crystal nanowire

NARCIS (Netherlands)

van den Berg, Albert; Bomer, Johan G.; Carlen, Edwin; Chen, S.; Kraaijenhagen, R.A.; Pinedo, Herbert Michael

2010-01-01

A method for manufacturing a single crystal nano-structure is provided comprising the steps of providing a device layer with a 100 structure on a substrate; providing a stress layer onto the device layer; patterning the stress layer along the 110 direction of the device layer; selectively removing

Single-step solution processing of small-molecule organic semiconductor field-effect transistors at high yield

NARCIS (Netherlands)

Yu, Liyang; Li, X.; Pavlica, E.; Loth, M.A.; Anthony, J.E.; Bratina, G.; Kjellander, B.K.C.; Gelinck, G.H.; Stutzmann, N.

2011-01-01

Here, we report a simple, alternative route towards high-mobility structures of the small-molecular semiconductor 5,11-bis(triethyl silylethynyl) anthradithiophene that requires one single processing step without the need for any post-deposition processing. The method relies on careful control of

Peyton’s four-step approach: differential effects of single instructional steps on procedural and memory performance – a clarification study

Directory of Open Access Journals (Sweden)

Krautter M

2015-05-01

Full Text Available Markus Krautter,1 Ronja Dittrich,2 Annette Safi,2 Justine Krautter,1 Imad Maatouk,2 Andreas Moeltner,2 Wolfgang Herzog,2 Christoph Nikendei2 1Department of Nephrology, 2Department of General Internal and Psychosomatic Medicine, University of Heidelberg Medical Hospital, Heidelberg, Germany Background: Although Peyton’s four-step approach is a widely used method for skills-lab training in undergraduate medical education and has been shown to be more effective than standard instruction, it is unclear whether its superiority can be attributed to a specific single step. Purpose: We conducted a randomized controlled trial to investigate the differential learning outcomes of the separate steps of Peyton’s four-step approach. Methods: Volunteer medical students were randomly assigned to four different groups. Step-1 group received Peyton’s Step 1, Step-2 group received Peyton’s Steps 1 and 2, Step-3 group received Peyton’s Steps 1, 2, and 3, and Step-3mod group received Peyton’s Steps 1 and 2, followed by a repetition of Step 2. Following the training, the first independent performance of a central venous catheter (CVC insertion using a manikin was video-recorded and scored by independent video assessors using binary checklists. The day after the training, memory performance during delayed recall was assessed with an incidental free recall test. Results: A total of 97 participants agreed to participate in the trial. There were no statistically significant group differences with regard to age, sex, completed education in a medical profession, completed medical clerkships, preliminary memory tests, or self-efficacy ratings. Regarding checklist ratings, Step-2 group showed a superior first independent performance of CVC placement compared to Step-1 group (P<0.001, and Step-3 group showed a superior performance to Step-2 group (P<0.009, while Step-2 group and Step-3mod group did not differ (P=0.055. The findings were similar in the incidental

Process analysis and modeling of a single-step lutein extraction method for wet microalgae.

Science.gov (United States)

Gong, Mengyue; Wang, Yuruihan; Bassi, Amarjeet

2017-11-01

Lutein is a commercial carotenoid with potential health benefits. Microalgae are alternative sources for the lutein production in comparison to conventional approaches using marigold flowers. In this study, a process analysis of a single-step simultaneous extraction, saponification, and primary purification process for free lutein production from wet microalgae biomass was carried out. The feasibility of binary solvent mixtures for wet biomass extraction was successfully demonstrated, and the extraction kinetics of lutein from chloroplast in microalgae were first evaluated. The effects of types of organic solvent, solvent polarity, cell disruption method, and alkali and solvent usage on lutein yields were examined. A mathematical model based on Fick's second law of diffusion was applied to model the experimental data. The mass transfer coefficients were used to estimate the extraction rates. The extraction rate was found more significantly related with alkali ratio to solvent than to biomass. The best conditions for extraction efficiency were found to be pre-treatment with ultrasonication at 0.5 s working cycle per second, react 0.5 h in 0.27 L/g solvent to biomass ratio, and 1:3 ether/ethanol (v/v) with 1.25 g KOH/L. The entire process can be controlled within 1 h and yield over 8 mg/g lutein, which is more economical for scale-up.

Response of single polymers to localized step strains

NARCIS (Netherlands)

Panja, D.

2009-01-01

In this paper, the response of single three-dimensional phantom and self-avoiding polymers to localized step strains are studied for two cases in the absence of hydrodynamic interactions: (i) Polymers tethered at one end with the strain created at the point of tether, and (ii) free polymers with the

A Normalized Transfer Matrix Method for the Free Vibration of Stepped Beams: Comparison with Experimental and FE(3D Methods

Directory of Open Access Journals (Sweden)

Tamer Ahmed El-Sayed

2017-01-01

Full Text Available The exact solution for multistepped Timoshenko beam is derived using a set of fundamental solutions. This set of solutions is derived to normalize the solution at the origin of the coordinates. The start, end, and intermediate boundary conditions involve concentrated masses and linear and rotational elastic supports. The beam start, end, and intermediate equations are assembled using the present normalized transfer matrix (NTM. The advantage of this method is that it is quicker than the standard method because the size of the complete system coefficient matrix is 4 × 4. In addition, during the assembly of this matrix, there are no inverse matrix steps required. The validity of this method is tested by comparing the results of the current method with the literature. Then the validity of the exact stepped analysis is checked using experimental and FE(3D methods. The experimental results for stepped beams with single step and two steps, for sixteen different test samples, are in excellent agreement with those of the three-dimensional finite element FE(3D. The comparison between the NTM method and the finite element method results shows that the modal percentage deviation is increased when a beam step location coincides with a peak point in the mode shape. Meanwhile, the deviation decreases when a beam step location coincides with a straight portion in the mode shape.

Single mode step-index polymer optical fiber for humidity insensitive high temperature fiber Bragg grating sensors

DEFF Research Database (Denmark)

Woyessa, Getinet; Fasano, Andrea; Stefani, Alessio

2016-01-01

We have fabricated the first single-mode step-index and humidity insensitive polymer optical fiber operating in the 850 nm wavelength ranges. The step-index preform is fabricated using injection molding, which is an efficient method for cost effective, flexible and fast preparation of the fiber...... preform. The fabricated single-mode step-index (SI) polymer optical fiber (POF) has a 4.8µm core made from TOPAS grade 5013S-04 with a glass transition temperature of 134°C and a 150 µm cladding made from ZEONEX grade 480R with a glass transition temperature of 138°C. The key advantages of the proposed...... SIPOF are low water absorption, high operating temperature and chemical inertness to acids and bases and many polar solvents as compared to the conventional poly-methyl-methacrylate (PMMA) and polystyrene based POFs. In addition, the fiber Bragg grating writing time is short compared to microstructured...

The Effects of Multiple-Step and Single-Step Directions on Fourth and Fifth Grade Students' Grammar Assessment Performance

Science.gov (United States)

Mazerik, Matthew B.

2006-01-01

The mean scores of English Language Learners (ELL) and English Only (EO) students in 4th and 5th grade (N = 110), across the teacher-administered Grammar Skills Test, were examined for differences in participants' scores on assessments containing single-step directions and assessments containing multiple-step directions. The results indicated no…

Single-step digital backpropagation for nonlinearity mitigation

DEFF Research Database (Denmark)

Secondini, Marco; Rommel, Simon; Meloni, Gianluca

2015-01-01

Nonlinearity mitigation based on the enhanced split-step Fourier method (ESSFM) for the implementation of low-complexity digital backpropagation (DBP) is investigated and experimentally demonstrated. After reviewing the main computational aspects of DBP and of the conventional split-step Fourier...... in the computational complexity, power consumption, and latency with respect to a simple feed-forward equalizer for bulk dispersion compensation....

METHOD FOR MANUFACTURING A SINGLE CRYSTAL NANO-WIRE.

NARCIS (Netherlands)

Van Den Berg, Albert; Bomer, Johan; Carlen Edwin, Thomas; Chen, Songyue; Kraaijenhagen Roderik, Adriaan; Pinedo Herbert, Michael

2011-01-01

A method for manufacturing a single crystal nano-structure is provided comprising the steps of providing a device layer with a 100 structure on a substrate; providing a stress layer onto the device layer; patterning the stress layer along the 110 direction of the device layer; selectively removing

Method for making a single-step etch mask for 3D monolithic nanostructures

International Nuclear Information System (INIS)

Grishina, D A; Harteveld, C A M; Vos, W L; Woldering, L A

2015-01-01

Current nanostructure fabrication by etching is usually limited to planar structures as they are defined by a planar mask. The realization of three-dimensional (3D) nanostructures by etching requires technologies beyond planar masks. We present a method for fabricating a 3D mask that allows one to etch three-dimensional monolithic nanostructures using only CMOS-compatible processes. The mask is written in a hard-mask layer that is deposited on two adjacent inclined surfaces of a Si wafer. By projecting in a single step two different 2D patterns within one 3D mask on the two inclined surfaces, the mutual alignment between the patterns is ensured. Thereby after the mask pattern is defined, the etching of deep pores in two oblique directions yields a three-dimensional structure in Si. As a proof of concept we demonstrate 3D mask fabrication for three-dimensional diamond-like photonic band gap crystals in silicon. The fabricated crystals reveal a broad stop gap in optical reflectivity measurements. We propose how 3D nanostructures with five different Bravais lattices can be realized, namely cubic, tetragonal, orthorhombic, monoclinic and hexagonal, and demonstrate a mask for a 3D hexagonal crystal. We also demonstrate the mask for a diamond-structure crystal with a 3D array of cavities. In general, the 2D patterns on the different surfaces can be completely independently structured and still be in perfect mutual alignment. Indeed, we observe an alignment accuracy of better than 3.0 nm between the 2D mask patterns on the inclined surfaces, which permits one to etch well-defined monolithic 3D nanostructures. (paper)

Single-step controlled-NOT logic from any exchange interaction

Science.gov (United States)

Galiautdinov, Andrei

2007-11-01

A self-contained approach to studying the unitary evolution of coupled qubits is introduced, capable of addressing a variety of physical systems described by exchange Hamiltonians containing Rabi terms. The method automatically determines both the Weyl chamber steering trajectory and the accompanying local rotations. Particular attention is paid to the case of anisotropic exchange with tracking controls, which is solved analytically. It is shown that, if computational subspace is well isolated, any exchange interaction can always generate high fidelity, single-step controlled-NOT (CNOT) logic, provided that both qubits can be individually manipulated. The results are then applied to superconducting qubit architectures, for which several CNOT gate implementations are identified. The paper concludes with consideration of two CNOT gate designs having high efficiency and operating with no significant leakage to higher-lying noncomputational states.

Characterization of cyclic deformation behaviour of tempered and quenched 42CrMoS4 at single step and variable amplitude loading

International Nuclear Information System (INIS)

Schelp, M.; Eifler, D.

2000-01-01

Cyclic single steps tests were performed on tempered and quenched specimens of the steel 42CrMoS4. Strain, temperature and electrical resistance measurements yielded an empirical prediction of fatigue life according to Coffin, Manson and Morrow. All measured values are based on physical processes and therefore show a strong interaction. A new testing procedure was developed permitting hysteresis measurements to be used for the characterization and description of fatigue behaviour under variable amplitude loading. The basic idea is to combine fatigue tests with any kind of load spectrum with single step tests. This offers the possibility to apply lifetime prediction methods normally used for single step tests for those with random or service loading. (orig.)

Step by step parallel programming method for molecular dynamics code

International Nuclear Information System (INIS)

Orii, Shigeo; Ohta, Toshio

1996-07-01

Parallel programming for a numerical simulation program of molecular dynamics is carried out with a step-by-step programming technique using the two phase method. As a result, within the range of a certain computing parameters, it is found to obtain parallel performance by using the level of parallel programming which decomposes the calculation according to indices of do-loops into each processor on the vector parallel computer VPP500 and the scalar parallel computer Paragon. It is also found that VPP500 shows parallel performance in wider range computing parameters. The reason is that the time cost of the program parts, which can not be reduced by the do-loop level of the parallel programming, can be reduced to the negligible level by the vectorization. After that, the time consuming parts of the program are concentrated on less parts that can be accelerated by the do-loop level of the parallel programming. This report shows the step-by-step parallel programming method and the parallel performance of the molecular dynamics code on VPP500 and Paragon. (author)

A quantitative comparison of single-cell whole genome amplification methods.

Directory of Open Access Journals (Sweden)

Charles F A de Bourcy

Full Text Available Single-cell sequencing is emerging as an important tool for studies of genomic heterogeneity. Whole genome amplification (WGA is a key step in single-cell sequencing workflows and a multitude of methods have been introduced. Here, we compare three state-of-the-art methods on both bulk and single-cell samples of E. coli DNA: Multiple Displacement Amplification (MDA, Multiple Annealing and Looping Based Amplification Cycles (MALBAC, and the PicoPLEX single-cell WGA kit (NEB-WGA. We considered the effects of reaction gain on coverage uniformity, error rates and the level of background contamination. We compared the suitability of the different WGA methods for the detection of copy-number variations, for the detection of single-nucleotide polymorphisms and for de-novo genome assembly. No single method performed best across all criteria and significant differences in characteristics were observed; the choice of which amplifier to use will depend strongly on the details of the type of question being asked in any given experiment.

Development of a method to extract and purify target compounds from medicinal plants in a single step: online hyphenation of expanded bed adsorption chromatography and countercurrent chromatography.

Science.gov (United States)

Li, Yang; Wang, Nan; Zhang, Min; Ito, Yoichiro; Zhang, Hongyang; Wang, Yuerong; Guo, Xin; Hu, Ping

2014-04-01

Pure compounds extracted and purified from natural sources are crucial to lead discovery and drug screening. This study presents a novel two-dimensional hyphenation of expanded bed adsorption chromatography (EBAC) and high-speed countercurrent chromatography (HSCCC) for extraction and purification of target compounds from medicinal plants in a single step. The EBAC and HSCCC were hyphenated via a six-port injection valve as an interface. Fractionation of ingredients of Salvia miltiorrhiza and Rhizoma coptidis was performed on the hyphenated system to verify its efficacy. Two compounds were harvested from Salvia miltiorrhiza, one was 52.9 mg of salvianolic acid B with an over 95% purity and the other was 2.1 mg of rosmarinic acid with a 74% purity. Another two components were purified from Rhizoma coptidis, one was 4.6 mg of coptisine with a 98% purity and one was 4.1 mg of berberine with a 82% purity. The processing time was nearly 50% that of the multistep method. The results indicate that the present method is a rapid and green way to harvest targets from medicinal plants in a single step.

Virtual substitution scan via single-step free energy perturbation.

Science.gov (United States)

Chiang, Ying-Chih; Wang, Yi

2016-02-05

With the rapid expansion of our computing power, molecular dynamics (MD) simulations ranging from hundreds of nanoseconds to microseconds or even milliseconds have become increasingly common. The majority of these long trajectories are obtained from plain (vanilla) MD simulations, where no enhanced sampling or free energy calculation method is employed. To promote the 'recycling' of these trajectories, we developed the Virtual Substitution Scan (VSS) toolkit as a plugin of the open-source visualization and analysis software VMD. Based on the single-step free energy perturbation (sFEP) method, VSS enables the user to post-process a vanilla MD trajectory for a fast free energy scan of substituting aryl hydrogens by small functional groups. Dihedrals of the functional groups are sampled explicitly in VSS, which improves the performance of the calculation and is found particularly important for certain groups. As a proof-of-concept demonstration, we employ VSS to compute the solvation free energy change upon substituting the hydrogen of a benzene molecule by 12 small functional groups frequently considered in lead optimization. Additionally, VSS is used to compute the relative binding free energy of four selected ligands of the T4 lysozyme. Overall, the computational cost of VSS is only a fraction of the corresponding multi-step FEP (mFEP) calculation, while its results agree reasonably well with those of mFEP, indicating that VSS offers a promising tool for rapid free energy scan of small functional group substitutions. This article is protected by copyright. All rights reserved. © 2016 Wiley Periodicals, Inc.

Single step radiolytic synthesis of iridium nanoparticles onto graphene oxide

International Nuclear Information System (INIS)

Rojas, J.V.; Molina Higgins, M.C.; Toro Gonzalez, M.; Castano, C.E.

2015-01-01

Graphical abstract: - Highlights: • Ir nanoparticles were synthesized through a single step gamma irradiation process. • Homogeneously distributed Ir nanoparticles on graphene oxide are ∼2.3 nm in size. • Ir−O bonds evidenced the interaction of the nanoparticles with the support. - Abstract: In this work a new approach to synthesize iridium nanoparticles on reduced graphene oxide is presented. The nanoparticles were directly deposited and grown on the surface of the carbon-based support using a single step reduction method through gamma irradiation. In this process, an aqueous isopropanol solution containing the iridium precursor, graphene oxide, and sodium dodecyl sulfate was initially prepared and sonicated thoroughly to obtain a homogeneous dispersion. The samples were irradiated with gamma rays with energies of 1.17 and 1.33 MeV emitted from the spontaneous decay of the 60 Co irradiator. The interaction of gamma rays with water in the presence of isopropanol generates highly reducing species homogeneously distributed in the solution that can reduce the Ir precursor down to a zero valence state. An absorbed dose of 60 kGy was used, which according to the yield of reducing species is sufficient to reduce the total amount of precursor present in the solution. This novel approach leads to the formation of 2.3 ± 0.5 nm Ir nanoparticles distributed along the surface of the support. The oxygenated functionalities of graphene oxide served as nucleation sites for the formation of Ir nuclei and their subsequent growth. XPS results revealed that the interaction of Ir with the support occurs through Ir−O bonds.

Evaluation of accuracy in implant site preparation performed in single- or multi-step drilling procedures.

Science.gov (United States)

Marheineke, Nadine; Scherer, Uta; Rücker, Martin; von See, Constantin; Rahlf, Björn; Gellrich, Nils-Claudius; Stoetzer, Marcus

2018-06-01

Dental implant failure and insufficient osseointegration are proven results of mechanical and thermal damage during the surgery process. We herein performed a comparative study of a less invasive single-step drilling preparation protocol and a conventional multiple drilling sequence. Accuracy of drilling holes was precisely analyzed and the influence of different levels of expertise of the handlers and additional use of drill template guidance was evaluated. Six experimental groups, deployed in an osseous study model, were representing template-guided and freehanded drilling actions in a stepwise drilling procedure in comparison to a single-drill protocol. Each experimental condition was studied by the drilling actions of respectively three persons without surgical knowledge as well as three highly experienced oral surgeons. Drilling actions were performed and diameters were recorded with a precision measuring instrument. Less experienced operators were able to significantly increase the drilling accuracy using a guiding template, especially when multi-step preparations are performed. Improved accuracy without template guidance was observed when experienced operators were executing single-step versus multi-step technique. Single-step drilling protocols have shown to produce more accurate results than multi-step procedures. The outcome of any protocol can be further improved by use of guiding templates. Operator experience can be a contributing factor. Single-step preparations are less invasive and are promoting osseointegration. Even highly experienced surgeons are achieving higher levels of accuracy by combining this technique with template guidance. Hereby template guidance enables a reduction of hands-on time and side effects during surgery and lead to a more predictable clinical diameter.

Avoid the tsunami of the Dirac sea in the imaginary time step method

International Nuclear Information System (INIS)

Zhang, Ying; Liang, Haozhao; Meng, Jie

2010-01-01

The discrete single-particle spectra in both the Fermi and Dirac sea have been calculated by the imaginary time step (ITS) method for the Schroedinger-like equation after avoiding the "tsunami" of the Dirac sea, i.e. the diving behavior of the single-particle level into the Dirac sea in the direct application of the ITS method for the Dirac equation. It is found that by the transform from the Dirac equation to the Schroedinger-like equation, the single-particle spectra, which extend from the positive to the negative infinity, can be separately obtained by the ITS evolution in either the Fermi sea or the Dirac sea. Identical results with those in the conventional shooting method have been obtained via the ITS evolution for the equivalent Schroedinger-like equation, which demonstrates the feasibility, practicality and reliability of the present algorithm and dispels the doubts on the ITS method in the relativistic system. (author)

Computing single step operators of logic programming in radial basis function neural networks

Science.gov (United States)

Hamadneh, Nawaf; Sathasivam, Saratha; Choon, Ong Hong

2014-07-01

Logic programming is the process that leads from an original formulation of a computing problem to executable programs. A normal logic program consists of a finite set of clauses. A valuation I of logic programming is a mapping from ground atoms to false or true. The single step operator of any logic programming is defined as a function (Tp:I→I). Logic programming is well-suited to building the artificial intelligence systems. In this study, we established a new technique to compute the single step operators of logic programming in the radial basis function neural networks. To do that, we proposed a new technique to generate the training data sets of single step operators. The training data sets are used to build the neural networks. We used the recurrent radial basis function neural networks to get to the steady state (the fixed point of the operators). To improve the performance of the neural networks, we used the particle swarm optimization algorithm to train the networks.

Computing single step operators of logic programming in radial basis function neural networks

Energy Technology Data Exchange (ETDEWEB)

Hamadneh, Nawaf; Sathasivam, Saratha; Choon, Ong Hong [School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia)

2014-07-10

Logic programming is the process that leads from an original formulation of a computing problem to executable programs. A normal logic program consists of a finite set of clauses. A valuation I of logic programming is a mapping from ground atoms to false or true. The single step operator of any logic programming is defined as a function (T{sub p}:I→I). Logic programming is well-suited to building the artificial intelligence systems. In this study, we established a new technique to compute the single step operators of logic programming in the radial basis function neural networks. To do that, we proposed a new technique to generate the training data sets of single step operators. The training data sets are used to build the neural networks. We used the recurrent radial basis function neural networks to get to the steady state (the fixed point of the operators). To improve the performance of the neural networks, we used the particle swarm optimization algorithm to train the networks.

Computing single step operators of logic programming in radial basis function neural networks

International Nuclear Information System (INIS)

Hamadneh, Nawaf; Sathasivam, Saratha; Choon, Ong Hong

2014-01-01

Logic programming is the process that leads from an original formulation of a computing problem to executable programs. A normal logic program consists of a finite set of clauses. A valuation I of logic programming is a mapping from ground atoms to false or true. The single step operator of any logic programming is defined as a function (T p :I→I). Logic programming is well-suited to building the artificial intelligence systems. In this study, we established a new technique to compute the single step operators of logic programming in the radial basis function neural networks. To do that, we proposed a new technique to generate the training data sets of single step operators. The training data sets are used to build the neural networks. We used the recurrent radial basis function neural networks to get to the steady state (the fixed point of the operators). To improve the performance of the neural networks, we used the particle swarm optimization algorithm to train the networks

Single-step colloidal quantum dot films for infrared solar harvesting

KAUST Repository

Kiani, Amirreza; Sutherland, Brandon R.; Kim, Younghoon; Ouellette, Olivier; Levina, Larissa; Walters, Grant; Dinh, Cao Thang; Liu, Mengxia; Voznyy, Oleksandr; Lan, Xinzheng; Labelle, Andre J.; Ip, Alexander H.; Proppe, Andrew; Ahmed, Ghada H.; Mohammed, Omar F.; Hoogland, Sjoerd; Sargent, Edward H.

2016-01-01

. To date, IR CQD solar cells have been made using a wasteful and complex sequential layer-by-layer process. Here, we demonstrate ∼1 eV bandgap solar-harvesting CQD films deposited in a single step. By engineering a fast-drying solvent mixture for metal

Determination of beam intensity in a single step for IMRT inverse planning

International Nuclear Information System (INIS)

Chuang, Keh-Shih; Chen, Tzong-Jer; Kuo, Shan-Chi; Jan, Meei-Ling; Hwang, Ing-Ming; Chen, Sharon; Lin, Ying-Chuan; Wu, Jay

2003-01-01

In intensity modulated radiotherapy (IMRT), targets are treated by multiple beams at different orientations each with spatially-modulated beam intensities. This approach spreads the normal tissue dose to a greater volume and produces a higher dose conformation to the target. In general, inverse planning is used for IMRT treatment planning. The inverse planning requires iterative calculation of dose distribution in order to optimize the intensity profile for each beam and is very computation intensive. In this paper, we propose a single-step method utilizing a figure of merit (FoM) to estimate the beam intensities for IMRT treatment planning. The FoM of a ray is defined as the ratio between the delivered tumour dose and normal tissue dose and is a good index for the dose efficacy of the ray. To maximize the beam utility, it is natural to irradiate the tumour with intensity of each ray proportional to the value of the FoM. The nonuniform beam intensity profiles are then fixed and the weights of the beam are determined iteratively in order to yield a uniform tumour dose. In this study, beams are employed at equispaced angles around the patient. Each beam with its field size that just covers the tumour is divided into a fixed number of beamlets. The FoM is calculated for each beamlet and this value is assigned to be the beam intensity. Various weighting factors are incorporated in the FoM computation to accommodate different clinical considerations. Two clinical datasets are used to test the feasibility of the algorithm. The resultant dose-volume histograms of this method are presented and compared to that of conformal therapy. Preliminary results indicate that this method reduces the critical organ doses at a small expense of uniformity in tumour dose distribution. This method estimates the beam intensity in one single step and the computation time is extremely fast and can be finished in less than one minute using a regular PC

Single-step linking transition from superdeformed to spherical states in {sup 143}Eu

Energy Technology Data Exchange (ETDEWEB)

Atac, A.; Axelsson, A.; Persson, J. [Uppsala Univ. (Sweden)] [and others

1996-12-31

A discrete {gamma}-ray transition which connects the second lowest SD state with a normally deformed one in {sup 143}Eu has been discovered. It has an energy of 3360.6 keV and carries 3.2 % of the full intensity of the SD band. It feeds into a nearly spherical state which is above the I = 35/2{sup +}, E=4947 keV level. The exact placement of the single-step link could, however, not be established due to the especially complicated level scheme in the region of interest. The angular correlation study favours a stretched dipole character for the 3360.6 keV transition. The single-step link agrees well with the previously determined two-step links, both with respect to energy and spin.

Single-step fabrication of electrodes with controlled nanostructured surface roughness using optically-induced electrodeposition

Science.gov (United States)

Liu, N.; Li, M.; Liu, L.; Yang, Y.; Mai, J.; Pu, H.; Sun, Y.; Li, W. J.

2018-02-01

The customized fabrication of microelectrodes from gold nanoparticles (AuNPs) has attracted much attention due to their numerous applications in chemistry and biomedical engineering, such as for surface-enhanced Raman spectroscopy (SERS) and as catalyst sites for electrochemistry. Herein, we present a novel optically-induced electrodeposition (OED) method for rapidly fabricating gold electrodes which are also surface-modified with nanoparticles in one single step. The electrodeposition mechanism, with respect to the applied AC voltage signal and the elapsed deposition time, on the resulting morphology and particle sizes was investigated. The results from SEM and AFM analysis demonstrated that 80-200 nm gold particles can be formed on the surface of the gold electrodes. Simultaneously, both the size of the nanoparticles and the roughness of the fabricated electrodes can be regulated by the deposition time. Compared to state-of-the-art methods for fabricating microelectrodes with AuNPs, such as nano-seed-mediated growth and conventional electrodeposition, this OED technique has several advantages including: (1) electrode fabrication and surface modification using nanoparticles are completed in a single step, eliminating the need for prefabricating micro electrodes; (2) the patterning of electrodes is defined using a digitally-customized, projected optical image rather than using fixed physical masks; and (3) both the fabrication and surface modification processes are rapid, and the entire fabrication process only requires less than 6 s.

Penerapan Metode Diagnosis Cepat Virus Avian Influenza H5N1 dengan Metode Single Step Multiplex RT-PCR

Directory of Open Access Journals (Sweden)

Aris Haryanto

2010-12-01

Full Text Available Avian influenza (AI virus is a segmented single stranded (ss RNA virus with negative polarity andbelong to the Orthomyxoviridae family. Diagnose of AI virus can be performed using conventional methodsbut it has low sensitivity and specificity. The objective of the research was to apply rapid, precise, andaccurate diagnostic method for AI virus and also to determine its type and subtype based on the SingleStep Multiplex Reverse Transcriptase-Polymerase Chain Reaction targeting M, H5, and N1 genes. In thismethod M, H5 and NI genes were simultaneously amplified in one PCR tube. The steps of this researchconsist of collecting viral RNAs from 10 different AI samples originated from Maros Disease InvestigationCenter during 2007. DNA Amplification was conducted by Simplex RT-PCR using M primer set. Then, bysingle step multiplex RT-PCR were conducted simultaneously using M, H5 and N1 primers set. The RTPCRproducts were then separated on 1.5% agarose gel, stained by ethidum bromide and visualized underUV transilluminator. Results showed that 8 of 10 RNA virus samples could be amplified by Simplex RTPCRfor M gene which generating a DNA fragment of 276 bp. Amplification using multiplex RT-PCRmethod showed two of 10 samples were AI positive using multiplex RT-PCR, three DNA fragments weregenerated consisting of 276 bp for M gene, 189 bp for H5 gene, and 131 bp for N1. In this study, rapid andeffective diagnosis method for AI virus can be conducted by using simultaneous Single Step Multiplex RTPCR.By this technique type and subtype of AI virus, can also be determined, especially H5N1.

Influence of application methods of one-step self-etching adhesives on microtensile bond strength

Directory of Open Access Journals (Sweden)

Chul-Kyu Choi,

2011-05-01

Full Text Available Objectives The purpose of this study was to evaluate the effect of various application methods of one-step self-etch adhesives to microtensile resin-dentin bond strength. Materials and Methods Thirty-six extracted human molars were used. The teeth were assigned randomly to twelve groups (n = 15, according to the three different adhesive systems (Clearfil Tri-S Bond, Adper Prompt L-Pop, G-Bond and application methods. The adhesive systems were applied on the dentin as follows: 1 The single coating, 2 The double coating, 3 Manual agitation, 4 Ultrasonic agitation. Following the adhesive application, light-cure composite resin was constructed. The restored teeth were stored in distilled water at room temperature for 24 hours, and prepared 15 specimens per groups. Then microtensile bond strength was measured and the failure mode was examined. Results Manual agitation and ultrasonic agitation of adhesive significantly increased the microtensile bond strength than single coating and double coating did. Double coating of adhesive significantly increased the microtensile bond strength than single coating did and there was no significant difference between the manual agitation and ultrasonic agitation group. There was significant difference in microtensile bonding strength among all adhesives and Clearfil Tri-S Bond showed the highest bond strength. Conclusions In one-step self-etching adhesives, there was significant difference according to application methods and type of adhesives. No matter of the material, the manual or ultrasonic agitation of the adhesive showed significantly higher microtensile bond strength.

Nanopatterning of magnetic disks by single-step Ar+ Ion projection

NARCIS (Netherlands)

Dietzel, A.H.; Berger, R.; Loeschner, H.; Platzgummer, E.; Stengl, G.; Bruenger, W.H.; Letzkus, F.

2003-01-01

Large-area Ar+ projection has been used to generate planar magnetic nanostructures on a 1¿-format hard disk in a single step (see Figure). The recording pattern was transferred to a Co/Pt multilayer without resist processes or any other contact to the delicate media surface. It is conceivable that

Two-step Raman spectroscopy method for tumor diagnosis

Science.gov (United States)

Zakharov, V. P.; Bratchenko, I. A.; Kozlov, S. V.; Moryatov, A. A.; Myakinin, O. O.; Artemyev, D. N.

2014-05-01

Two-step Raman spectroscopy phase method was proposed for differential diagnosis of malignant tumor in skin and lung tissue. It includes detection of malignant tumor in healthy tissue on first step with identification of concrete cancer type on the second step. Proposed phase method analyze spectral intensity alteration in 1300-1340 and 1640-1680 cm-1 Raman bands in relation to the intensity of the 1450 cm-1 band on first step, and relative differences between RS intensities for tumor area and healthy skin closely adjacent to the lesion on the second step. It was tested more than 40 ex vivo samples of lung tissue and more than 50 in vivo skin tumors. Linear Discriminant Analysis, Quadratic Discriminant Analysis and Support Vector Machine were used for tumors type classification on phase planes. It is shown that two-step phase method allows to reach 88.9% sensitivity and 87.8% specificity for malignant melanoma diagnosis (skin cancer); 100% sensitivity and 81.5% specificity for adenocarcinoma diagnosis (lung cancer); 90.9% sensitivity and 77.8% specificity for squamous cell carcinoma diagnosis (lung cancer).

Structural comparison of anodic nanoporous-titania fabricated from single-step and three-step of anodization using two paralleled-electrodes anodizing cell

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Mallika Thabuot

2016-02-01

Full Text Available Anodization of Ti sheet in the ethylene glycol electrolyte containing 0.38wt% NH4F with the addition of 1.79wt% H2O at room temperature was studied. Applied potential of 10-60 V and anodizing time of 1-3 h were conducted by single-step and three-step of anodization within the two paralleled-electrodes anodizing cell. Their structural and textural properties were investigated by X-ray diffraction (XRD and scanning electron microscopy (SEM. After annealing at 600°C in the air furnace for 3 h, TiO2-nanotubes was transformed to the higher proportion of anatase crystal phase. Also crystallization of anatase phase was enhanced as the duration of anodization as the final step increased. By using single-step of anodization, pore texture of oxide film was started to reveal at the applied potential of 30 V. Better orderly arrangement of the TiO2-nanotubes array with larger pore size was obtained with the increase of applied potential. The applied potential of 60 V was selected for the three-step of anodization with anodizing time of 1-3 h. Results showed that the well-smooth surface coverage with higher density of porous-TiO2 was achieved using prolonging time at the first and second step, however, discontinuity tube in length was produced instead of the long-vertical tube. Layer thickness of anodic oxide film depended on the anodizing time at the last step of anodization. More well arrangement of nanostructured-TiO2 was produced using three-step of anodization under 60 V with 3 h for each step.

Differences in Lower Extremity and Trunk Kinematics between Single Leg Squat and Step Down Tasks.

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Cara L Lewis

Full Text Available The single leg squat and single leg step down are two commonly used functional tasks to assess movement patterns. It is unknown how kinematics compare between these tasks. The purpose of this study was to identify kinematic differences in the lower extremity, pelvis and trunk between the single leg squat and the step down. Fourteen healthy individuals participated in this research and performed the functional tasks while kinematic data were collected for the trunk, pelvis, and lower extremities using a motion capture system. For the single leg squat task, the participant was instructed to squat as low as possible. For the step down task, the participant was instructed to stand on top of a box, slowly lower him/herself until the non-stance heel touched the ground, and return to standing. This was done from two different heights (16 cm and 24 cm. The kinematics were evaluated at peak knee flexion as well as at 60° of knee flexion. Pearson correlation coefficients (r between the angles at those two time points were also calculated to better understand the relationship between each task. The tasks resulted in kinematics differences at the knee, hip, pelvis, and trunk at both time points. The single leg squat was performed with less hip adduction (p ≤ 0.003, but more hip external rotation and knee abduction (p ≤ 0.030, than the step down tasks at 60° of knee flexion. These differences were maintained at peak knee flexion except hip external rotation was only significant in the 24 cm step down task (p ≤ 0.029. While there were multiple differences between the two step heights at peak knee flexion, the only difference at 60° of knee flexion was in trunk flexion (p < 0.001. Angles at the knee and hip had a moderate to excellent correlation (r = 0.51-0.98, but less consistently so at the pelvis and trunk (r = 0.21-0.96. The differences in movement patterns between the single leg squat and the step down should be considered when selecting a

Strong Stability Preserving Explicit Linear Multistep Methods with Variable Step Size

KAUST Repository

Hadjimichael, Yiannis

2016-09-08

Strong stability preserving (SSP) methods are designed primarily for time integration of nonlinear hyperbolic PDEs, for which the permissible SSP step size varies from one step to the next. We develop the first SSP linear multistep methods (of order two and three) with variable step size, and prove their optimality, stability, and convergence. The choice of step size for multistep SSP methods is an interesting problem because the allowable step size depends on the SSP coefficient, which in turn depends on the chosen step sizes. The description of the methods includes an optimal step-size strategy. We prove sharp upper bounds on the allowable step size for explicit SSP linear multistep methods and show the existence of methods with arbitrarily high order of accuracy. The effectiveness of the methods is demonstrated through numerical examples.

Antibacterial and cytocompatible nanotextured Ti surface incorporating silver via single step hydrothermal processing

Energy Technology Data Exchange (ETDEWEB)

Mohandas, Anu; Krishnan, Amit G.; Biswas, Raja; Menon, Deepthy, E-mail: deepthymenon@aims.amrita.edu; Nair, Manitha B., E-mail: manithanair@aims.amrita.edu

2017-06-01

Nanosurface modification of Titanium (Ti) implants and prosthesis is proved to enhance osseointegration at the tissue–implant interface. However, many of these products lack adequate antibacterial capability, which leads to implant loosening. As a curative strategy, in this study, nanotextured Ti substrates embedded with silver nanoparticles were developed through a single step hydrothermal processing in an alkaline medium containing silver nitrate at different concentrations (15, 30 and 75 μM). Scanning electron micrographs revealed a non-periodically oriented nanoleafy structure on Ti (TNL) decorated with Ag nanoparticles (nanoAg), which was verified by XPS, XRD and EDS analysis. This TNLAg substrate proved to be mechanically stable upon nanoindentation and nanoscratch tests. Silver ions at detectable levels were released for a period of ~ 28 days only from substrates incorporating higher nanoAg content. The samples demonstrated antibacterial activity towards both Escherichia coli and Staphylococcus aureus, with a more favorable response to the former. Simultaneously, Ti substrates incorporating nanoAg at all concentrations supported the viability, proliferation and osteogenic differentiation of mesenchymal stem cells. Overall, nanoAg incorporation into surface modified Ti via a simple one-step thermochemical method is a favorable strategy for producing implants with dual characteristics of antibacterial activity and cell compatibility. - Highlights: • Nanosilver was incorporated within Ti nanoleafy topography by simple one-step thermochemical method • The nanosurface demonstrated antibacterial activity against gram positive and gram negative bacteria • The nanosurface promoted the viability, proliferation and osteogenic differentiation of mesenchymal stem cells.

Balanced Photodetection in One-Step Liquid-Phase-Synthesized CsPbBr3 Micro-/Nanoflake Single Crystals.

Science.gov (United States)

Zheng, Wei; Xiong, Xufan; Lin, Richeng; Zhang, Zhaojun; Xu, Cunhua; Huang, Feng

2018-01-17

Here, we reported a low-cost and high-compatibility one-step liquid-phase synthesis method for synthesizing high-purity CsPbBr 3 micro-/nanoflake single crystals. On the basis of the high-purity CsPbBr 3 , we further prepared a low-dimensional photodetector capable of balanced photodetection, involving both high external quantum efficiency and rapid temporal response, which is barely realized in previously reported low-dimensional photodetectors.

Single step synthesis, characterization and applications of curcumin functionalized iron oxide magnetic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Bhandari, Rohit; Gupta, Prachi; Dziubla, Thomas; Hilt, J. Zach, E-mail: zach.hilt@uky.edu

2016-10-01

Magnetic iron oxide nanoparticles have been well known for their applications in magnetic resonance imaging (MRI), hyperthermia, targeted drug delivery, etc. The surface modification of these magnetic nanoparticles has been explored extensively to achieve functionalized materials with potential application in biomedical, environmental and catalysis field. Herein, we report a novel and versatile single step methodology for developing curcumin functionalized magnetic Fe{sub 3}O{sub 4} nanoparticles without any additional linkers, using a simple coprecipitation technique. The magnetic nanoparticles (MNPs) were characterized using transmission electron microscopy, X-ray diffraction, fourier transform infrared spectroscopy and thermogravimetric analysis. The developed MNPs were employed in a cellular application for protection against an inflammatory agent, a polychlorinated biphenyl (PCB) molecule. - Graphical abstract: Novel single step curcumin coated magnetic Fe{sub 3}O{sub 4} nanoparticles without any additional linkers for medical, environmental, and other applications. Display Omitted - Highlights: • A novel and versatile single step methodology for developing curcumin functionalized magnetic Fe{sub 3}O{sub 4} nanoparticles is reported. • The magnetic nanoparticles (MNPs) were characterized using TEM, XRD, FTIR and TGA. • The developed MNPs were employed in a cellular application for protection against an inflammatory agent, a polychlorinated biphenyl (PCB).

Single step vacuum-free and hydrogen-free synthesis of graphene

Directory of Open Access Journals (Sweden)

Christian Orellana

2017-08-01

Full Text Available We report a modified method to grow graphene in a single-step process. It is based on chemical vapor deposition and considers the use of methane under extremely adverse synthesis conditions, namely in an open chamber without requiring the addition of gaseous hydrogen in any of the synthesis stages. The synthesis occurs between two parallel Cu plates, heated up via electromagnetic induction. The inductive heating yields a strong thermal gradient between the catalytic substrates and the surrounding environment, promoting the enrichment of hydrogen generated as fragments of the methane molecules within the volume confined by the Cu foils. This induced density gradient is due to thermo-diffusion, also known as the Soret effect. Hydrogen and other low mass molecular fractions produced during the process inhibit oxidative effects and simultaneously reduce the native oxide on the Cu surface. As a result, high quality graphene is obtained on the inner surfaces of the Cu sheets as confirmed by Raman spectroscopy.

Separation of Be and Al for AMS using single-step column chromatography

Energy Technology Data Exchange (ETDEWEB)

Binnie, Steven A., E-mail: sbinnie@uni-koeln.de [Institute for Geology und Mineralogy, University of Cologne, 4-6 Greinstrasse, Cologne D-50939 (Germany); Dunai, Tibor J.; Voronina, Elena; Goral, Tomasz [Institute for Geology und Mineralogy, University of Cologne, 4-6 Greinstrasse, Cologne D-50939 (Germany); Heinze, Stefan; Dewald, Alfred [University of Cologne, Institut für Kernphysik, Zülpicher Str. 77, Cologne D-50937 (Germany)

2015-10-15

With the aim of simplifying AMS target preparation procedures for TCN measurements we tested a new extraction chromatography approach which couples an anion exchange resin (WBEC) to a chelating resin (Beryllium resin) to separate Be and Al from dissolved quartz samples. Results show that WBEC–Beryllium resin stacks can be used to provide high purity Be and Al separations using a combination of hydrochloric/oxalic and nitric acid elutions. {sup 10}Be and {sup 26}Al concentrations from quartz samples prepared using more standard procedures are compared with results from replicate samples prepared using the coupled WBEC–Beryllium resin approach and show good agreement. The new column procedure is performed in a single step, reducing sample preparation times relative to more traditional methods of TCN target production.

Separation of Be and Al for AMS using single-step column chromatography

Science.gov (United States)

Binnie, Steven A.; Dunai, Tibor J.; Voronina, Elena; Goral, Tomasz; Heinze, Stefan; Dewald, Alfred

2015-10-01

With the aim of simplifying AMS target preparation procedures for TCN measurements we tested a new extraction chromatography approach which couples an anion exchange resin (WBEC) to a chelating resin (Beryllium resin) to separate Be and Al from dissolved quartz samples. Results show that WBEC-Beryllium resin stacks can be used to provide high purity Be and Al separations using a combination of hydrochloric/oxalic and nitric acid elutions. 10Be and 26Al concentrations from quartz samples prepared using more standard procedures are compared with results from replicate samples prepared using the coupled WBEC-Beryllium resin approach and show good agreement. The new column procedure is performed in a single step, reducing sample preparation times relative to more traditional methods of TCN target production.

TODIM Method for Single-Valued Neutrosophic Multiple Attribute Decision Making

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Dong-Sheng Xu

2017-10-01

Full Text Available Recently, the TODIM has been used to solve multiple attribute decision making (MADM problems. The single-valued neutrosophic sets (SVNSs are useful tools to depict the uncertainty of the MADM. In this paper, we will extend the TODIM method to the MADM with the single-valued neutrosophic numbers (SVNNs. Firstly, the definition, comparison, and distance of SVNNs are briefly presented, and the steps of the classical TODIM method for MADM problems are introduced. Then, the extended classical TODIM method is proposed to deal with MADM problems with the SVNNs, and its significant characteristic is that it can fully consider the decision makers’ bounded rationality which is a real action in decision making. Furthermore, we extend the proposed model to interval neutrosophic sets (INSs. Finally, a numerical example is proposed.

Single-step generation of metal-plasma polymer multicore@shell nanoparticles from the gas phase.

Science.gov (United States)

Solař, Pavel; Polonskyi, Oleksandr; Olbricht, Ansgar; Hinz, Alexander; Shelemin, Artem; Kylián, Ondřej; Choukourov, Andrei; Faupel, Franz; Biederman, Hynek

2017-08-17

Nanoparticles composed of multiple silver cores and a plasma polymer shell (multicore@shell) were prepared in a single step with a gas aggregation cluster source operating with Ar/hexamethyldisiloxane mixtures and optionally oxygen. The size distribution of the metal inclusions as well as the chemical composition and the thickness of the shells were found to be controlled by the composition of the working gas mixture. Shell matrices ranging from organosilicon plasma polymer to nearly stoichiometric SiO 2 were obtained. The method allows facile fabrication of multicore@shell nanoparticles with tailored functional properties, as demonstrated here with the optical response.

Aesthetic rehabilitation of a patient with an anterior maxillectomy defect, using an innovative single-step, single unit, plastic-based hollow obturator

Directory of Open Access Journals (Sweden)

Vishwas Bhatia

2015-06-01

Full Text Available What could be better than improving the comfort and quality of life of a patient with a life-threatening disease? Maxillectomy, the partial or total removal of the maxilla in patients suffering from benign or malignant neoplasms, creates a challenging defect for the maxillofacial prosthodontist when attempting to provide an effective obturator. Although previous methods have been described for rehabilitation of such patients, our goal should be to devise one stage techniques that will allow the patient an improved quality of life as soon as possible. The present report describes the aesthetic rehabilitation of a maxillectomy patient by use of a hollow obturator. The obturator is fabricated through a processing technique which is a variation of other well-known techniques, consisting of the use of a single-step flasking procedure to fabricate a single-unit hollow obturator using the lost salt technique. As our aim is to aesthetically and functionally rehabilitate the patient as soon as possible, the present method of restoring the maxillectomy defect is cost-effective, time-saving and beneficial for the patient.

Improved perovskite phototransistor prepared using multi-step annealing method

Science.gov (United States)

Cao, Mingxuan; Zhang, Yating; Yu, Yu; Yao, Jianquan

2018-02-01

Organic-inorganic hybrid perovskites with good intrinsic physical properties have received substantial interest for solar cell and optoelectronic applications. However, perovskite film always suffers from a low carrier mobility due to its structural imperfection including sharp grain boundaries and pinholes, restricting their device performance and application potential. Here we demonstrate a straightforward strategy based on multi-step annealing process to improve the performance of perovskite photodetector. Annealing temperature and duration greatly affects the surface morphology and optoelectrical properties of perovskites which determines the device property of phototransistor. The perovskite films treated with multi-step annealing method tend to form highly uniform, well-crystallized and high surface coverage perovskite film, which exhibit stronger ultraviolet-visible absorption and photoluminescence spectrum compare to the perovskites prepared by conventional one-step annealing process. The field-effect mobilities of perovskite photodetector treated by one-step direct annealing method shows mobility as 0.121 (0.062) cm2V-1s-1 for holes (electrons), which increases to 1.01 (0.54) cm2V-1s-1 for that treated with muti-step slow annealing method. Moreover, the perovskite phototransistors exhibit a fast photoresponse speed of 78 μs. In general, this work focuses on the influence of annealing methods on perovskite phototransistor, instead of obtains best parameters of it. These findings prove that Multi-step annealing methods is feasible to prepared high performance based photodetector.

Two-step single slope/SAR ADC with error correction for CMOS image sensor.

Science.gov (United States)

Tang, Fang; Bermak, Amine; Amira, Abbes; Amor Benammar, Mohieddine; He, Debiao; Zhao, Xiaojin

2014-01-01

Conventional two-step ADC for CMOS image sensor requires full resolution noise performance in the first stage single slope ADC, leading to high power consumption and large chip area. This paper presents an 11-bit two-step single slope/successive approximation register (SAR) ADC scheme for CMOS image sensor applications. The first stage single slope ADC generates a 3-bit data and 1 redundant bit. The redundant bit is combined with the following 8-bit SAR ADC output code using a proposed error correction algorithm. Instead of requiring full resolution noise performance, the first stage single slope circuit of the proposed ADC can tolerate up to 3.125% quantization noise. With the proposed error correction mechanism, the power consumption and chip area of the single slope ADC are significantly reduced. The prototype ADC is fabricated using 0.18 μ m CMOS technology. The chip area of the proposed ADC is 7 μ m × 500 μ m. The measurement results show that the energy efficiency figure-of-merit (FOM) of the proposed ADC core is only 125 pJ/sample under 1.4 V power supply and the chip area efficiency is 84 k  μ m(2) · cycles/sample.

Two-Step Single Slope/SAR ADC with Error Correction for CMOS Image Sensor

Directory of Open Access Journals (Sweden)

Fang Tang

2014-01-01

Full Text Available Conventional two-step ADC for CMOS image sensor requires full resolution noise performance in the first stage single slope ADC, leading to high power consumption and large chip area. This paper presents an 11-bit two-step single slope/successive approximation register (SAR ADC scheme for CMOS image sensor applications. The first stage single slope ADC generates a 3-bit data and 1 redundant bit. The redundant bit is combined with the following 8-bit SAR ADC output code using a proposed error correction algorithm. Instead of requiring full resolution noise performance, the first stage single slope circuit of the proposed ADC can tolerate up to 3.125% quantization noise. With the proposed error correction mechanism, the power consumption and chip area of the single slope ADC are significantly reduced. The prototype ADC is fabricated using 0.18 μm CMOS technology. The chip area of the proposed ADC is 7 μm × 500 μm. The measurement results show that the energy efficiency figure-of-merit (FOM of the proposed ADC core is only 125 pJ/sample under 1.4 V power supply and the chip area efficiency is 84 k μm2·cycles/sample.

Solving point reactor kinetic equations by time step-size adaptable numerical methods

International Nuclear Information System (INIS)

Liao Chaqing

2007-01-01

Based on the analysis of effects of time step-size on numerical solutions, this paper showed the necessity of step-size adaptation. Based on the relationship between error and step-size, two-step adaptation methods for solving initial value problems (IVPs) were introduced. They are Two-Step Method and Embedded Runge-Kutta Method. PRKEs were solved by implicit Euler method with step-sizes optimized by using Two-Step Method. It was observed that the control error has important influence on the step-size and the accuracy of solutions. With suitable control errors, the solutions of PRKEs computed by the above mentioned method are accurate reasonably. The accuracy and usage of MATLAB built-in ODE solvers ode23 and ode45, both of which adopt Runge-Kutta-Fehlberg method, were also studied and discussed. (authors)

Modeling single-file diffusion with step fractional Brownian motion and a generalized fractional Langevin equation

International Nuclear Information System (INIS)

Lim, S C; Teo, L P

2009-01-01

Single-file diffusion behaves as normal diffusion at small time and as subdiffusion at large time. These properties can be described in terms of fractional Brownian motion with variable Hurst exponent or multifractional Brownian motion. We introduce a new stochastic process called Riemann–Liouville step fractional Brownian motion which can be regarded as a special case of multifractional Brownian motion with a step function type of Hurst exponent tailored for single-file diffusion. Such a step fractional Brownian motion can be obtained as a solution of the fractional Langevin equation with zero damping. Various kinds of fractional Langevin equations and their generalizations are then considered in order to decide whether their solutions provide the correct description of the long and short time behaviors of single-file diffusion. The cases where the dissipative memory kernel is a Dirac delta function, a power-law function and a combination of these functions are studied in detail. In addition to the case where the short time behavior of single-file diffusion behaves as normal diffusion, we also consider the possibility of a process that begins as ballistic motion

Dispersed single-phase-step Michelson interferometer for Doppler imaging using sunlight.

Science.gov (United States)

Wan, Xiaoke; Ge, Jian

2012-09-15

A Michelson interferometer is dispersed with a fiber array-fed spectrograph, providing 59 Doppler sensing channels using sunlight in the 510-570 nm wavelength region. The interferometer operates at a single-phase-step mode, which is particularly advantageous in multiplexing and data processing compared to the phase-stepping mode of other interferometer spectrometer instruments. Spectral templates are prepared using a standard solar spectrum and simulated interferometer modulations, such that the correlation function with a measured 1D spectrum determines the Doppler shift. Doppler imaging of a rotating cylinder is demonstrated. The average Doppler sensitivity is ~12 m/s, with some channels reaching ~5 m/s.

A novel single-step procedure for the calibration of the mounting parameters of a multi-camera terrestrial mobile mapping system

Science.gov (United States)

Habib, A.; Kersting, P.; Bang, K.; Rau, J.

2011-12-01

Mobile Mapping Systems (MMS) can be defined as moving platforms which integrates a set of imaging sensors and a position and orientation system (POS) for the collection of geo-spatial information. In order to fully explore the potential accuracy of such systems and guarantee accurate multi-sensor integration, a careful system calibration must be carried out. System calibration involves individual sensor calibration as well as the estimation of the inter-sensor geometric relationship. This paper tackles a specific component of the system calibration process of a multi-camera MMS - the estimation of the relative orientation parameters among the cameras, i.e., the inter-camera geometric relationship (lever-arm offsets and boresight angles among the cameras). For that purpose, a novel single step procedure, which is easy to implement and not computationally intensive, will be introduced. The proposed method is implemented in such a way that it can also be used for the estimation of the mounting parameters among the cameras and the IMU body frame, in case of directly georeferenced systems. The performance of the proposed method is evaluated through experimental results using simulated data. A comparative analysis between the proposed single-step and the two-step, which makes use of the traditional bundle adjustment procedure, is demonstrated.

New 'one-step' method for the simultaneous synthesis and anchoring of organic monolith inside COC microchip channels

International Nuclear Information System (INIS)

Ladner, Yoann; Cretier, Gerard; Dugas, Vincent; Randon, Jerome; Faure, Karine; Bruchet, Anthony

2012-01-01

A new method for monolith synthesis and anchoring inside cyclic olefin copolymer (COC) microchannels in a single step is proposed. It is shown that type I photo-initiators, typically used in a polymerization mixture to generate free radicals during monolith synthesis, can simultaneously act as type II photo-initiators and react with the plastic surface through hydrogen abstraction. This mechanism is used to 'photo-graft' poly(ethylene glycol) methacrylate (PEGMA) on COC surfaces. Contact angle measurements were used to observe the changes in surface hydrophilicity when increasing initiator concentration and irradiation duration. The ability of type I photo-initiators to synthesize and anchor a monolith inside COC microchannels in a single step was proved through SEM observations. Different concentrations of photo-initiators were tried. Finally, electro-chromatographic separations of polycyclic aromatic hydrocarbons were realized to illustrate the beneficial effect of anchoring on chromatographic performances. The versatility of the method was demonstrated with two widely used photo-initiators: benzoin methyl ether (BME) and azobisisobutyronitrile (AIBN). (authors)

A step-by-step workflow for low-level analysis of single-cell RNA-seq data with Bioconductor [version 2; referees: 1 approved, 4 approved with reservations

Directory of Open Access Journals (Sweden)

Aaron T.L. Lun

2016-10-01

Full Text Available Single-cell RNA sequencing (scRNA-seq is widely used to profile the transcriptome of individual cells. This provides biological resolution that cannot be matched by bulk RNA sequencing, at the cost of increased technical noise and data complexity. The differences between scRNA-seq and bulk RNA-seq data mean that the analysis of the former cannot be performed by recycling bioinformatics pipelines for the latter. Rather, dedicated single-cell methods are required at various steps to exploit the cellular resolution while accounting for technical noise. This article describes a computational workflow for low-level analyses of scRNA-seq data, based primarily on software packages from the open-source Bioconductor project. It covers basic steps including quality control, data exploration and normalization, as well as more complex procedures such as cell cycle phase assignment, identification of highly variable and correlated genes, clustering into subpopulations and marker gene detection. Analyses were demonstrated on gene-level count data from several publicly available datasets involving haematopoietic stem cells, brain-derived cells, T-helper cells and mouse embryonic stem cells. This will provide a range of usage scenarios from which readers can construct their own analysis pipelines.

Strong Stability Preserving Two-step Runge–Kutta Methods

KAUST Repository

Ketcheson, David I.; Gottlieb, Sigal; Macdonald, Colin B.

2011-01-01

We investigate the strong stability preserving (SSP) property of two-step Runge–Kutta (TSRK) methods. We prove that all SSP TSRK methods belong to a particularly simple subclass of TSRK methods, in which stages from the previous step are not used. We derive simple order conditions for this subclass. Whereas explicit SSP Runge–Kutta methods have order at most four, we prove that explicit SSP TSRK methods have order at most eight. We present explicit TSRK methods of up to eighth order that were found by numerical search. These methods have larger SSP coefficients than any known methods of the same order of accuracy and may be implemented in a form with relatively modest storage requirements. The usefulness of the TSRK methods is demonstrated through numerical examples, including integration of very high order weighted essentially non-oscillatory discretizations.

Strong Stability Preserving Two-step Runge–Kutta Methods

KAUST Repository

Ketcheson, David I.

2011-12-22

We investigate the strong stability preserving (SSP) property of two-step Runge–Kutta (TSRK) methods. We prove that all SSP TSRK methods belong to a particularly simple subclass of TSRK methods, in which stages from the previous step are not used. We derive simple order conditions for this subclass. Whereas explicit SSP Runge–Kutta methods have order at most four, we prove that explicit SSP TSRK methods have order at most eight. We present explicit TSRK methods of up to eighth order that were found by numerical search. These methods have larger SSP coefficients than any known methods of the same order of accuracy and may be implemented in a form with relatively modest storage requirements. The usefulness of the TSRK methods is demonstrated through numerical examples, including integration of very high order weighted essentially non-oscillatory discretizations.

Single-Stage Step up/down Driver for Permanent-Magnet Synchronous Machines

Science.gov (United States)

Chen, T. R.; Juan, Y. L.; Huang, C. Y.; Kuo, C. T.

2017-11-01

The two-stage circuit composed of a step up/down dc converter and a three-phase voltage source inverter is usually adopted as the electric vehicle’s motor driver. The conventional topology is more complicated. Additional power loss resulted from twice power conversion would also cause lower efficiency. A single-stage step up/down Permanent-Magnet Synchronous Motor driver for Brushless DC (BLDC) Motor is proposed in this study. The number components and circuit complexity are reduced. The low frequency six-step square-wave control is used to reduce the switching losses. In the proposed topology, only one active switch is gated with a high frequency PWM signal for adjusting the rotation speed. The rotor position signals are fed back to calculate the motor speed for digital close-loop control in a MCU. A 600W prototype circuit is constructed to drive a BLDC motor with rated speed 3000 rpm, and can control the speed of six sections.

"Silicon millefeuille": From a silicon wafer to multiple thin crystalline films in a single step

Science.gov (United States)

Hernández, David; Trifonov, Trifon; Garín, Moisés; Alcubilla, Ramon

2013-04-01

During the last years, many techniques have been developed to obtain thin crystalline films from commercial silicon ingots. Large market applications are foreseen in the photovoltaic field, where important cost reductions are predicted, and also in advanced microelectronics technologies as three-dimensional integration, system on foil, or silicon interposers [Dross et al., Prog. Photovoltaics 20, 770-784 (2012); R. Brendel, Thin Film Crystalline Silicon Solar Cells (Wiley-VCH, Weinheim, Germany 2003); J. N. Burghartz, Ultra-Thin Chip Technology and Applications (Springer Science + Business Media, NY, USA, 2010)]. Existing methods produce "one at a time" silicon layers, once one thin film is obtained, the complete process is repeated to obtain the next layer. Here, we describe a technology that, from a single crystalline silicon wafer, produces a large number of crystalline films with controlled thickness in a single technological step.

Single step sequential polydimethylsiloxane wet etching to fabricate a microfluidic channel with various cross-sectional geometries

Science.gov (United States)

Wang, C.-K.; Liao, W.-H.; Wu, H.-M.; Lo, Y.-H.; Lin, T.-R.; Tung, Y.-C.

2017-11-01

Polydimethylsiloxane (PDMS) has become a widely used material to construct microfluidic devices for various biomedical and chemical applications due to its desirable material properties and manufacturability. PDMS microfluidic devices are usually fabricated using soft lithography replica molding methods with master molds made of photolithogrpahy patterned photoresist layers on silicon wafers. The fabricated microfluidic channels often have rectangular cross-sectional geometries with single or multiple heights. In this paper, we develop a single step sequential PDMS wet etching process that can be used to fabricate microfluidic channels with various cross-sectional geometries from single-layer PDMS microfluidic channels. The cross-sections of the fabricated channel can be non-rectangular, and varied along the flow direction. Furthermore, the fabricated cross-sectional geometries can be numerically simulated beforehand. In the experiments, we fabricate microfluidic channels with various cross-sectional geometries using the developed technique. In addition, we fabricate a microfluidic mixer with alternative mirrored cross-sectional geometries along the flow direction to demonstrate the practical usage of the developed technique.

Development of a new Xe-133 single dose multi-step method (SDMM) for muscle blood flow measurement using gamma camera

International Nuclear Information System (INIS)

Bunko, Hisashi; Seto, Mikito; Taki, Junichi

1985-01-01

In order to measure the muscle blood flow (MBF) during exercise (Ex), a new Xe-133 single dose multi-step method (SDMM) for leg MBF measurement before, during and after Ex using gamma camera was developped. Theoretically, if the activity of Xe-133 in the muscle immediately before and after Ex are known, then the mean MBF during Ex can be calculated. In SDMM, these activities are corrected through correction formula using time delays between end of data aquisition (DA) at rest (R1) and begining of the Ex (TAB), and between end of Ex and begining of the DA after Ex (R2) (TDA). Validity of the SDMM and MBF response on mild and heavy Ex were evaluated in 11 normal volunteers. Ex MBF calculated from 5 and 2.5 min DA (5 sec/frame) both at R1 and R2 were highly correlated (r=.996). Ex MBF by SDMM and direct(measurement by fixed leg exercise were also highly correlated (r=.999). Reproducibility of the R1 and Ex MBF were excellent (r=.999). The highest MBF was seen in GCM on miled walking Ex and in VLM on heavy squatting Ex. After miled Ex, MBF rapidly returned to normal. After heavy Ex, MBF remaind high in VLM In conclusion, SDMM is simple and accurate method for evaluation of dynamic MBF response according to exercise. SDMM is also applicable to the field of sports medicine. (author)

A three-step vehicle detection framework for range estimation using a single camera

CSIR Research Space (South Africa)

Kanjee, R

2015-12-01

Full Text Available This paper proposes and validates a real-time onroad vehicle detection system, which uses a single camera for the purpose of intelligent driver assistance. A three-step vehicle detection framework is presented to detect and track the target vehicle...

An Improved Single-Step Cloning Strategy Simplifies the Agrobacterium tumefaciens-Mediated Transformation (ATMT)-Based Gene-Disruption Method for Verticillium dahliae.

Science.gov (United States)

Wang, Sheng; Xing, Haiying; Hua, Chenlei; Guo, Hui-Shan; Zhang, Jie

2016-06-01

The soilborne fungal pathogen Verticillium dahliae infects a broad range of plant species to cause severe diseases. The availability of Verticillium genome sequences has provided opportunities for large-scale investigations of individual gene function in Verticillium strains using Agrobacterium tumefaciens-mediated transformation (ATMT)-based gene-disruption strategies. Traditional ATMT vectors require multiple cloning steps and elaborate characterization procedures to achieve successful gene replacement; thus, these vectors are not suitable for high-throughput ATMT-based gene deletion. Several advancements have been made that either involve simplification of the steps required for gene-deletion vector construction or increase the efficiency of the technique for rapid recombinant characterization. However, an ATMT binary vector that is both simple and efficient is still lacking. Here, we generated a USER-ATMT dual-selection (DS) binary vector, which combines both the advantages of the USER single-step cloning technique and the efficiency of the herpes simplex virus thymidine kinase negative-selection marker. Highly efficient deletion of three different genes in V. dahliae using the USER-ATMT-DS vector enabled verification that this newly-generated vector not only facilitates the cloning process but also simplifies the subsequent identification of fungal homologous recombinants. The results suggest that the USER-ATMT-DS vector is applicable for efficient gene deletion and suitable for large-scale gene deletion in V. dahliae.

Quickest single-step one pot mechanosynthesis and characterization of ZnTe quantum dots

Energy Technology Data Exchange (ETDEWEB)

Patra, S. [Dept of Physics, University of Burdwan, Golapbag, Burdwan, West Bengal 713104 (India); Pradhan, S.K., E-mail: skp_bu@yahoo.com [Dept of Physics, University of Burdwan, Golapbag, Burdwan, West Bengal 713104 (India)

2011-05-05

Research highlights: > First time quickest mechanosynthesis of ZnTe QDs starting from Zn and Te powders. > Cubic ZnTe are formed in a single pot at RT in a single step within 1 h of milling. > The existence of stacking faults and twin faults are evident from HRTEM images. > Distinct blue shift has been observed in UV-vis absorption spectra. > First time report that ZnTe QDs with faults can also show the quantum size effect. - Abstract: ZnTe quantum dots (QDs) are synthesized at room temperature in a single step by mechanical alloying the stoichiometric equimolar mixture (1:1 mol) of Zn and Te powders under Ar within 1 h of milling. Both XRD and HRTEM characterizations reveal that these QDs having size {approx}5 nm contain stacking faults of different kinds. A distinct blue-shift in absorption spectra with decreasing particle size of QDs confirms the quantum size confinement effect (QSCE). It is observed for first time that the QDs with considerable amount of faults can also show the QSCE. Optical band gaps of these QDs increase with increasing milling time and their band gaps can be fine-tuned easily by varying milling time of QDs.

An improved 4-step commutation method application for matrix converter

DEFF Research Database (Denmark)

Guo, Yu; Guo, Yougui; Deng, Wenlang

2014-01-01

A novel four-step commutation method is proposed for matrix converter cell, 3 phase inputs to 1 phase output in this paper, which is obtained on the analysis of published commutation methods for matrix converter. The first and fourth step can be shorter than the second or third one. The discussed...... method here is implemented by programming in VHDL language. Finally, the novel method in this paper is verified by experiments....

A rapid, ratiometric, enzyme-free, and sensitive single-step miRNA detection using three-way junction based FRET probes

Science.gov (United States)

Luo, Qingying; Liu, Lin; Yang, Cai; Yuan, Jing; Feng, Hongtao; Chen, Yan; Zhao, Peng; Yu, Zhiqiang; Jin, Zongwen

2018-03-01

MicroRNAs (miRNAs) are single stranded endogenous molecules composed of only 18-24 nucleotides which are critical for gene expression regulating the translation of messenger RNAs. Conventional methods based on enzyme-assisted nucleic acid amplification techniques have many problems, such as easy contamination, high cost, susceptibility to false amplification, and tendency to have sequence mismatches. Here we report a rapid, ratiometric, enzyme-free, sensitive, and highly selective single-step miRNA detection using three-way junction assembled (or self-assembled) FRET probes. The developed strategy can be operated within the linear range from subnanomolar to hundred nanomolar concentrations of miRNAs. In comparison with the traditional approaches, our method showed high sensitivity for the miRNA detection and extreme selectivity for the efficient discrimination of single-base mismatches. The results reveal that the strategy paved a new avenue for the design of novel highly specific probes applicable in diagnostics and potentially in microscopic imaging of miRNAs in real biological environments.

Gallium arsenide single crystal solar cell structure and method of making

Science.gov (United States)

Stirn, Richard J. (Inventor)

1983-01-01

A production method and structure for a thin-film GaAs crystal for a solar cell on a single-crystal silicon substrate (10) comprising the steps of growing a single-crystal interlayer (12) of material having a closer match in lattice and thermal expansion with single-crystal GaAs than the single-crystal silicon of the substrate, and epitaxially growing a single-crystal film (14) on the interlayer. The material of the interlayer may be germanium or graded germanium-silicon alloy, with low germanium content at the silicon substrate interface, and high germanium content at the upper surface. The surface of the interface layer (12) is annealed for recrystallization by a pulsed beam of energy (laser or electron) prior to growing the interlayer. The solar cell structure may be grown as a single-crystal n.sup.+ /p shallow homojunction film or as a p/n or n/p junction film. A Ga(Al)AS heteroface film may be grown over the GaAs film.

Method of forming catalyst layer by single step infiltration

Science.gov (United States)

Gerdes, Kirk; Lee, Shiwoo; Dowd, Regis

2018-05-01

Provided herein is a method for electrocatalyst infiltration of a porous substrate, of particular use for preparation of a cathode for a solid oxide fuel cell. The method generally comprises preparing an electrocatalyst infiltrate solution comprising an electrocatalyst, surfactant, chelating agent, and a solvent; pretreating a porous mixed ionic-electric conductive substrate; and applying the electrocatalyst infiltration solution to the porous mixed ionic-electric conductive substrate.

Three-Step Predictor-Corrector of Exponential Fitting Method for Nonlinear Schroedinger Equations

International Nuclear Information System (INIS)

Tang Chen; Zhang Fang; Yan Haiqing; Luo Tao; Chen Zhanqing

2005-01-01

We develop the three-step explicit and implicit schemes of exponential fitting methods. We use the three-step explicit exponential fitting scheme to predict an approximation, then use the three-step implicit exponential fitting scheme to correct this prediction. This combination is called the three-step predictor-corrector of exponential fitting method. The three-step predictor-corrector of exponential fitting method is applied to numerically compute the coupled nonlinear Schroedinger equation and the nonlinear Schroedinger equation with varying coefficients. The numerical results show that the scheme is highly accurate.

New Systematic CFD Methods to Calculate Static and Single Dynamic Stability Derivatives of Aircraft

Directory of Open Access Journals (Sweden)

Bai-gang Mi

2017-01-01

Full Text Available Several new systematic methods for high fidelity and reliability calculation of static and single dynamic derivatives are proposed in this paper. Angle of attack step response is used to obtain static derivative directly; then translation acceleration dynamic derivative and rotary dynamic derivative can be calculated by employing the step response motion of rate of the angle of attack and unsteady motion of pitching angular velocity step response, respectively. Longitudinal stability derivative calculations of SACCON UCAV are taken as test cases for validation. Numerical results of all cases achieve good agreement with reference values or experiments data from wind tunnel, which indicate that the proposed methods can be considered as new tools in the process of design and production of advanced aircrafts for their high efficiency and precision.

Development of single step RT-PCR for detection of Kyasanur forest disease virus from clinical samples

Directory of Open Access Journals (Sweden)

Gouri Chaubal

2018-02-01

Discussion and conclusion: The previously published sensitive real time RT-PCR assay requires higher cost in terms of reagents and machine setup and technical expertise has been the primary reason for development of this assay. A single step RT-PCR is relatively easy to perform and more cost effective than real time RT-PCR in smaller setups in the absence of Biosafety Level-3 facility. This study reports the development and optimization of single step RT-PCR assay which is more sensitive and less time-consuming than nested RT-PCR and cost effective for rapid diagnosis of KFD viral RNA.

A stabilized Runge–Kutta–Legendre method for explicit super-time-stepping of parabolic and mixed equations

International Nuclear Information System (INIS)

Meyer, Chad D.; Balsara, Dinshaw S.; Aslam, Tariq D.

2014-01-01

Parabolic partial differential equations appear in several physical problems, including problems that have a dominant hyperbolic part coupled to a sub-dominant parabolic component. Explicit methods for their solution are easy to implement but have very restrictive time step constraints. Implicit solution methods can be unconditionally stable but have the disadvantage of being computationally costly or difficult to implement. Super-time-stepping methods for treating parabolic terms in mixed type partial differential equations occupy an intermediate position. In such methods each superstep takes “s” explicit Runge–Kutta-like time-steps to advance the parabolic terms by a time-step that is s 2 times larger than a single explicit time-step. The expanded stability is usually obtained by mapping the short recursion relation of the explicit Runge–Kutta scheme to the recursion relation of some well-known, stable polynomial. Prior work has built temporally first- and second-order accurate super-time-stepping methods around the recursion relation associated with Chebyshev polynomials. Since their stability is based on the boundedness of the Chebyshev polynomials, these methods have been called RKC1 and RKC2. In this work we build temporally first- and second-order accurate super-time-stepping methods around the recursion relation associated with Legendre polynomials. We call these methods RKL1 and RKL2. The RKL1 method is first-order accurate in time; the RKL2 method is second-order accurate in time. We verify that the newly-designed RKL1 and RKL2 schemes have a very desirable monotonicity preserving property for one-dimensional problems – a solution that is monotone at the beginning of a time step retains that property at the end of that time step. It is shown that RKL1 and RKL2 methods are stable for all values of the diffusion coefficient up to the maximum value. We call this a convex monotonicity preserving property and show by examples that it is very useful

Structural Studies of Silver Nanoparticles Obtained Through Single-Step Green Synthesis

Science.gov (United States)

Prasad Peddi, Siva; Abdallah Sadeh, Bilal

2015-10-01

Green synthesis of silver Nanoparticles (AGNP's) has been the most prominent among the metallic nanoparticles for research for over a decade and half now due to both the simplicity of preparation and the applicability of biological species with extensive applications in medicine and biotechnology to reduce and trap the particles. The current article uses Eclipta Prostrata leaf extract as the biological species to cap the AGNP's through a single step process. The characterization data obtained was used for the analysis of the sample structure. The article emphasizes the disquisition of their shape and size of the lattice parameters and proposes a general scheme and a mathematical model for the analysis of their dependence. The data of the synthesized AGNP's has been used to advantage through the introduction of a structural shape factor for the crystalline nanoparticles. The properties of the structure of the AGNP's proposed and evaluated through a theoretical model was undeviating with the experimental consequences. This modus operandi gives scope for the structural studies of ultrafine particles prepared using biological methods.

A MISO-ARX-Based Method for Single-Trial Evoked Potential Extraction

Directory of Open Access Journals (Sweden)

Nannan Yu

2017-01-01

Full Text Available In this paper, we propose a novel method for solving the single-trial evoked potential (EP estimation problem. In this method, the single-trial EP is considered as a complex containing many components, which may originate from different functional brain sites; these components can be distinguished according to their respective latencies and amplitudes and are extracted simultaneously by multiple-input single-output autoregressive modeling with exogenous input (MISO-ARX. The extraction process is performed in three stages: first, we use a reference EP as a template and decompose it into a set of components, which serve as subtemplates for the remaining steps. Then, a dictionary is constructed with these subtemplates, and EPs are preliminarily extracted by sparse coding in order to roughly estimate the latency of each component. Finally, the single-trial measurement is parametrically modeled by MISO-ARX while characterizing spontaneous electroencephalographic activity as an autoregression model driven by white noise and with each component of the EP modeled by autoregressive-moving-average filtering of the subtemplates. Once optimized, all components of the EP can be extracted. Compared with ARX, our method has greater tracking capabilities of specific components of the EP complex as each component is modeled individually in MISO-ARX. We provide exhaustive experimental results to show the effectiveness and feasibility of our method.

Fabrication of Polydimethylsiloxane Microlenses Utilizing Hydrogel Shrinkage and a Single Molding Step

Directory of Open Access Journals (Sweden)

Bader Aldalali

2014-05-01

Full Text Available We report on polydimethlysiloxane (PDMS microlenses and microlens arrays on flat and curved substrates fabricated via a relatively simple process combining liquid-phase photopolymerization and a single molding step. The mold for the formation of the PDMS lenses is fabricated by photopolymerizing a polyacrylamide (PAAm pre-hydrogel. The shrinkage of PAAm after its polymerization forms concave lenses. The lenses are then transferred to PDMS by a single step molding to form PDMS microlens array on a flat substrate. The PAAm concave lenses are also transferred to PDMS and another flexible polymer, Solaris, to realize artificial compound eyes. The resultant microlenses and microlens arrays possess good uniformity and optical properties. The focal length of the lenses is inversely proportional to the shrinkage time. The microlens mold can also be rehydrated to change the focal length of the ultimate PDMS microlenses. The spherical aberration is 2.85 μm and the surface roughness is on the order of 204 nm. The microlenses can resolve 10.10 line pairs per mm (lp/mm and have an f-number range between f/2.9 and f/56.5. For the compound eye, the field of view is 113°.

Handbook of statistical methods single subject design

CERN Document Server

Satake, Eiki; Maxwell, David L

2008-01-01

This book is a practical guide of the most commonly used approaches in analyzing and interpreting single-subject data. It arranges the methodologies used in a logical sequence using an array of research studies from the existing published literature to illustrate specific applications. The book provides a brief discussion of each approach such as visual, inferential, and probabilistic model, the applications for which it is intended, and a step-by-step illustration of the test as used in an actual research study.

Quantitative Single-letter Sequencing: a method for simultaneously monitoring numerous known allelic variants in single DNA samples

Directory of Open Access Journals (Sweden)

Duborjal Hervé

2008-02-01

Full Text Available Abstract Background Pathogens such as fungi, bacteria and especially viruses, are highly variable even within an individual host, intensifying the difficulty of distinguishing and accurately quantifying numerous allelic variants co-existing in a single nucleic acid sample. The majority of currently available techniques are based on real-time PCR or primer extension and often require multiplexing adjustments that impose a practical limitation of the number of alleles that can be monitored simultaneously at a single locus. Results Here, we describe a novel method that allows the simultaneous quantification of numerous allelic variants in a single reaction tube and without multiplexing. Quantitative Single-letter Sequencing (QSS begins with a single PCR amplification step using a pair of primers flanking the polymorphic region of interest. Next, PCR products are submitted to single-letter sequencing with a fluorescently-labelled primer located upstream of the polymorphic region. The resulting monochromatic electropherogram shows numerous specific diagnostic peaks, attributable to specific variants, signifying their presence/absence in the DNA sample. Moreover, peak fluorescence can be quantified and used to estimate the frequency of the corresponding variant in the DNA population. Using engineered allelic markers in the genome of Cauliflower mosaic virus, we reliably monitored six different viral genotypes in DNA extracted from infected plants. Evaluation of the intrinsic variance of this method, as applied to both artificial plasmid DNA mixes and viral genome populations, demonstrates that QSS is a robust and reliable method of detection and quantification for variants with a relative frequency of between 0.05 and 1. Conclusion This simple method is easily transferable to many other biological systems and questions, including those involving high throughput analysis, and can be performed in any laboratory since it does not require specialized

Multi-Level Wavelet Shannon Entropy-Based Method for Single-Sensor Fault Location

Directory of Open Access Journals (Sweden)

Qiaoning Yang

2015-10-01

Full Text Available In actual application, sensors are prone to failure because of harsh environments, battery drain, and sensor aging. Sensor fault location is an important step for follow-up sensor fault detection. In this paper, two new multi-level wavelet Shannon entropies (multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are defined. They take full advantage of sensor fault frequency distribution and energy distribution across multi-subband in wavelet domain. Based on the multi-level wavelet Shannon entropy, a method is proposed for single sensor fault location. The method firstly uses a criterion of maximum energy-to-Shannon entropy ratio to select the appropriate wavelet base for signal analysis. Then multi-level wavelet time Shannon entropy and multi-level wavelet time-energy Shannon entropy are used to locate the fault. The method is validated using practical chemical gas concentration data from a gas sensor array. Compared with wavelet time Shannon entropy and wavelet energy Shannon entropy, the experimental results demonstrate that the proposed method can achieve accurate location of a single sensor fault and has good anti-noise ability. The proposed method is feasible and effective for single-sensor fault location.

Strong Stability Preserving Explicit Linear Multistep Methods with Variable Step Size

KAUST Repository

Hadjimichael, Yiannis; Ketcheson, David I.; Loczi, Lajos; Né meth, Adriá n

2016-01-01

Strong stability preserving (SSP) methods are designed primarily for time integration of nonlinear hyperbolic PDEs, for which the permissible SSP step size varies from one step to the next. We develop the first SSP linear multistep methods (of order

A method for using unmanned aerial vehicles for emergency investigation of single geo-hazards and sample applications of this method

Science.gov (United States)

Huang, Haifeng; Long, Jingjing; Yi, Wu; Yi, Qinglin; Zhang, Guodong; Lei, Bangjun

2017-11-01

In recent years, unmanned aerial vehicles (UAVs) have become widely used in emergency investigations of major natural hazards over large areas; however, UAVs are less commonly employed to investigate single geo-hazards. Based on a number of successful investigations in the Three Gorges Reservoir area, China, a complete UAV-based method for performing emergency investigations of single geo-hazards is described. First, a customized UAV system that consists of a multi-rotor UAV subsystem, an aerial photography subsystem, a ground control subsystem and a ground surveillance subsystem is described in detail. The implementation process, which includes four steps, i.e., indoor preparation, site investigation, on-site fast processing and application, and indoor comprehensive processing and application, is then elaborated, and two investigation schemes, automatic and manual, that are used in the site investigation step are put forward. Moreover, some key techniques and methods - e.g., the layout and measurement of ground control points (GCPs), route planning, flight control and image collection, and the Structure from Motion (SfM) photogrammetry processing - are explained. Finally, three applications are given. Experience has shown that using UAVs for emergency investigation of single geo-hazards greatly reduces the time, intensity and risks associated with on-site work and provides valuable, high-accuracy, high-resolution information that supports emergency responses.

Designed optimization of a single-step extraction of fucose-containing sulfated polysaccharides from Sargassum sp

DEFF Research Database (Denmark)

Ale, Marcel Tutor; Mikkelsen, Jørn Dalgaard; Meyer, Anne S.

2012-01-01

Fucose-containing sulfated polysaccharides can be extracted from the brown seaweed, Sargassum sp. It has been reported that fucose-rich sulfated polysaccharides from brown seaweeds exert different beneficial biological activities including anti-inflammatory, anticoagulant, and anti-viral effects....... Classical extraction of fucose-containing sulfated polysaccharides from brown seaweed species typically involves extended, multiple-step, hot acid, or CaCl2 treatments, each step lasting several hours. In this work, we systematically examined the influence of acid concentration (HCl), time, and temperature...... on the yield of fucosecontaining sulfated polysaccharides (FCSPs) in statistically designed two-step and single-step multifactorial extraction experiments. All extraction factors had significant effects on the fucose-containing sulfated polysaccharides yield, with the temperature and time exerting positive...

Perturbed Strong Stability Preserving Time-Stepping Methods For Hyperbolic PDEs

KAUST Repository

Hadjimichael, Yiannis

2017-09-30

A plethora of physical phenomena are modelled by hyperbolic partial differential equations, for which the exact solution is usually not known. Numerical methods are employed to approximate the solution to hyperbolic problems; however, in many cases it is difficult to satisfy certain physical properties while maintaining high order of accuracy. In this thesis, we develop high-order time-stepping methods that are capable of maintaining stability constraints of the solution, when coupled with suitable spatial discretizations. Such methods are called strong stability preserving (SSP) time integrators, and we mainly focus on perturbed methods that use both upwind- and downwind-biased spatial discretizations. Firstly, we introduce a new family of third-order implicit Runge–Kuttas methods with arbitrarily large SSP coefficient. We investigate the stability and accuracy of these methods and we show that they perform well on hyperbolic problems with large CFL numbers. Moreover, we extend the analysis of SSP linear multistep methods to semi-discretized problems for which different terms on the right-hand side of the initial value problem satisfy different forward Euler (or circle) conditions. Optimal perturbed and additive monotonicity-preserving linear multistep methods are studied in the context of such problems. Optimal perturbed methods attain augmented monotonicity-preserving step sizes when the different forward Euler conditions are taken into account. On the other hand, we show that optimal SSP additive methods achieve a monotonicity-preserving step-size restriction no better than that of the corresponding non-additive SSP linear multistep methods. Furthermore, we develop the first SSP linear multistep methods of order two and three with variable step size, and study their optimality. We describe an optimal step-size strategy and demonstrate the effectiveness of these methods on various one- and multi-dimensional problems. Finally, we establish necessary conditions

MIDPOINT TWO- STEPS RULE FOR THE SQUARE ROOT METHOD

African Journals Online (AJOL)

DR S.E UWAMUSI

Aberth third order method for finding zeros of a polynomial in interval ... KEY WORDS: Square root iteration, midpoint two steps Method, ...... A New set of Methods for the simultaneous determination of zeros of polynomial equation and iterative ...

A GPU-accelerated semi-implicit fractional-step method for numerical solutions of incompressible Navier-Stokes equations

Science.gov (United States)

Ha, Sanghyun; Park, Junshin; You, Donghyun

2018-01-01

Utility of the computational power of Graphics Processing Units (GPUs) is elaborated for solutions of incompressible Navier-Stokes equations which are integrated using a semi-implicit fractional-step method. The Alternating Direction Implicit (ADI) and the Fourier-transform-based direct solution methods used in the semi-implicit fractional-step method take advantage of multiple tridiagonal matrices whose inversion is known as the major bottleneck for acceleration on a typical multi-core machine. A novel implementation of the semi-implicit fractional-step method designed for GPU acceleration of the incompressible Navier-Stokes equations is presented. Aspects of the programing model of Compute Unified Device Architecture (CUDA), which are critical to the bandwidth-bound nature of the present method are discussed in detail. A data layout for efficient use of CUDA libraries is proposed for acceleration of tridiagonal matrix inversion and fast Fourier transform. OpenMP is employed for concurrent collection of turbulence statistics on a CPU while the Navier-Stokes equations are computed on a GPU. Performance of the present method using CUDA is assessed by comparing the speed of solving three tridiagonal matrices using ADI with the speed of solving one heptadiagonal matrix using a conjugate gradient method. An overall speedup of 20 times is achieved using a Tesla K40 GPU in comparison with a single-core Xeon E5-2660 v3 CPU in simulations of turbulent boundary-layer flow over a flat plate conducted on over 134 million grids. Enhanced performance of 48 times speedup is reached for the same problem using a Tesla P100 GPU.

Considerations for the independent reaction times and step-by-step methods for radiation chemistry simulations

Science.gov (United States)

Plante, Ianik; Devroye, Luc

2017-10-01

Ionizing radiation interacts with the water molecules of the tissues mostly by ionizations and excitations, which result in the formation of the radiation track structure and the creation of radiolytic species such as H.,.OH, H2, H2O2, and e-aq. After their creation, these species diffuse and may chemically react with the neighboring species and with the molecules of the medium. Therefore radiation chemistry is of great importance in radiation biology. As the chemical species are not distributed homogeneously, the use of conventional models of homogeneous reactions cannot completely describe the reaction kinetics of the particles. Actually, many simulations of radiation chemistry are done using the Independent Reaction Time (IRT) method, which is a very fast technique to calculate radiochemical yields but which do not calculate the positions of the radiolytic species as a function of time. Step-by-step (SBS) methods, which are able to provide such information, have been used only sparsely because these are time-consuming in terms of calculation. Recent improvements in computer performance now allow the regular use of the SBS method in radiation chemistry. The SBS and IRT methods are both based on the Green's functions of the diffusion equation (GFDE). In this paper, several sampling algorithms of the GFDE and for the IRT method are presented. We show that the IRT and SBS methods are exactly equivalent for 2-particles systems for diffusion and partially diffusion-controlled reactions between non-interacting particles. We also show that the results obtained with the SBS simulation method with periodic boundary conditions are in agreement with the predictions by classical reaction kinetics theory, which is an important step towards using this method for modelling of biochemical networks and metabolic pathways involved in oxidative stress. Finally, the first simulation results obtained with the code RITRACKS (Relativistic Ion Tracks) are presented.

The Fractional Step Method Applied to Simulations of Natural Convective Flows

Science.gov (United States)

Westra, Douglas G.; Heinrich, Juan C.; Saxon, Jeff (Technical Monitor)

2002-01-01

This paper describes research done to apply the Fractional Step Method to finite-element simulations of natural convective flows in pure liquids, permeable media, and in a directionally solidified metal alloy casting. The Fractional Step Method has been applied commonly to high Reynold's number flow simulations, but is less common for low Reynold's number flows, such as natural convection in liquids and in permeable media. The Fractional Step Method offers increased speed and reduced memory requirements by allowing non-coupled solution of the pressure and the velocity components. The Fractional Step Method has particular benefits for predicting flows in a directionally solidified alloy, since other methods presently employed are not very efficient. Previously, the most suitable method for predicting flows in a directionally solidified binary alloy was the penalty method. The penalty method requires direct matrix solvers, due to the penalty term. The Fractional Step Method allows iterative solution of the finite element stiffness matrices, thereby allowing more efficient solution of the matrices. The Fractional Step Method also lends itself to parallel processing, since the velocity component stiffness matrices can be built and solved independently of each other. The finite-element simulations of a directionally solidified casting are used to predict macrosegregation in directionally solidified castings. In particular, the finite-element simulations predict the existence of 'channels' within the processing mushy zone and subsequently 'freckles' within the fully processed solid, which are known to result from macrosegregation, or what is often referred to as thermo-solutal convection. These freckles cause material property non-uniformities in directionally solidified castings; therefore many of these castings are scrapped. The phenomenon of natural convection in an alloy under-going directional solidification, or thermo-solutal convection, will be explained. The

Voluntary stepping behavior under single- and dual-task conditions in chronic stroke survivors: A comparison between the involved and uninvolved legs.

Science.gov (United States)

Melzer, Itshak; Goldring, Melissa; Melzer, Yehudit; Green, Elad; Tzedek, Irit

2010-12-01

If balance is lost, quick step execution can prevent falls. Research has shown that speed of voluntary stepping was able to predict future falls in old adults. The aim of the study was to investigate voluntary stepping behavior, as well as to compare timing and leg push-off force-time relation parameters of involved and uninvolved legs in stroke survivors during single- and dual-task conditions. We also aimed to compare timing and leg push-off force-time relation parameters between stroke survivors and healthy individuals in both task conditions. Ten stroke survivors performed a voluntary step execution test with their involved and uninvolved legs under two conditions: while focusing only on the stepping task and while a separate attention-demanding task was performed simultaneously. Temporal parameters related to the step time were measured including the duration of the step initiation phase, the preparatory phase, the swing phase, and the total step time. In addition, force-time parameters representing the push-off power during stepping were calculated from ground reaction data and compared with 10 healthy controls. The involved legs of stroke survivors had a significantly slower stepping time than uninvolved legs due to increased swing phase duration during both single- and dual-task conditions. For dual compared to single task, the stepping time increased significantly due to a significant increase in the duration of step initiation. In general, the force time parameters were significantly different in both legs of stroke survivors as compared to healthy controls, with no significant effect of dual compared with single-task conditions in both groups. The inability of stroke survivors to swing the involved leg quickly may be the most significant factor contributing to the large number of falls to the paretic side. The results suggest that stroke survivors were unable to rapidly produce muscle force in fast actions. This may be the mechanism of delayed execution

Single step, pH induced gold nanoparticle chain formation in lecithin/water system.

Science.gov (United States)

Sharma, Damyanti

2013-07-01

Gold nanoparticle (AuNP) chains have been formed by a single step method in a lecithin/water system where lecithin itself plays the role of a reductant and a template for AuNP chain formation. Two preparative strategies were explored: (1) evaporating lecithin solution with aqueous gold chloride (HAuCl4) at different pHs and (2) dispersing lecithin vesicles in aqueous HAuCl4 solutions of various pHs in the range of 2.5-11.3. In method 1, at initial pH 2.5, 20-50 nm AuNPs are found attached to lecithin vesicles. When pH is raised to 5.5 there are no vesicles present and 20 nm monodisperse particles are found aggregating. Chain formation of fine nanoparticles (3-5 nm) is observed from neutral to basic pH, between 6.5-10.3 The chains formed are hundreds of nanometers to micrometer long and are usually 2-3 nanoparticles wide. On further increasing pH to 11.3, particles form disk-like or raft-like structures. When method (ii) was used a little chain formation was observed. Most of the nanoparticles formed were found either sitting together as raft like structures or scattered on lecithin structures. Copyright © 2013 Elsevier B.V. All rights reserved.

A Spiral Step-by-Step Educational Method for Cultivating Competent Embedded System Engineers to Meet Industry Demands

Science.gov (United States)

Jing,Lei; Cheng, Zixue; Wang, Junbo; Zhou, Yinghui

2011-01-01

Embedded system technologies are undergoing dramatic change. Competent embedded system engineers are becoming a scarce resource in the industry. Given this, universities should revise their specialist education to meet industry demands. In this paper, a spirally tight-coupled step-by-step educational method, based on an analysis of industry…

Cellobiohydrolase 1 from Trichoderma reesei degrades cellulose in single cellobiose steps

Science.gov (United States)

Brady, Sonia K.; Sreelatha, Sarangapani; Feng, Yinnian; Chundawat, Shishir P. S.; Lang, Matthew J.

2015-12-01

Cellobiohydrolase 1 from Trichoderma reesei (TrCel7A) processively hydrolyses cellulose into cellobiose. Although enzymatic techniques have been established as promising tools in biofuel production, a clear understanding of the motor's mechanistic action has yet to be revealed. Here, we develop an optical tweezers-based single-molecule (SM) motility assay for precision tracking of TrCel7A. Direct observation of motility during degradation reveals processive runs and distinct steps on the scale of 1 nm. Our studies suggest TrCel7A is not mechanically limited, can work against 20 pN loads and speeds up when assisted. Temperature-dependent kinetic studies establish the energy requirements for the fundamental stepping cycle, which likely includes energy from glycosidic bonds and other sources. Through SM measurements of isolated TrCel7A domains, we determine that the catalytic domain alone is sufficient for processive motion, providing insight into TrCel7A's molecular motility mechanism.

Sci-Thur PM - Colourful Interactions: Highlights 08: ARC TBI using Single-Step Optimized VMAT Fields

International Nuclear Information System (INIS)

Hudson, Alana; Gordon, Deborah; Moore, Roseanne; Balogh, Alex; Pierce, Greg

2016-01-01

Purpose: This work outlines a new TBI delivery technique to replace a lateral POP full bolus technique. The new technique is done with VMAT arc delivery, without bolus, treating the patient prone and supine. The benefits of the arc technique include: increased patient experience and safety, better dose conformity, better organ at risk sparing, decreased therapist time and reduction of therapist injuries. Methods: In this work we build on a technique developed by Jahnke et al. We use standard arc fields with gantry speeds corrected for varying distance to the patient followed by a single step VMAT optimization on a patient CT to increase dose inhomogeneity and to reduce dose to the lungs (vs. blocks). To compare the arc TBI technique to our full bolus technique, we produced plans on patient CTs for both techniques and evaluated several dosimetric parameters using an ANOVA test. Results and Conclusions: The arc technique is able reduce both the hot areas to the body (D2% reduced from 122.2% to 111.8% p<0.01) and the lungs (mean lung dose reduced from 107.5% to 99.1%, p<0.01), both statistically significant, while maintaining coverage (D98% = 97.8% vs. 94.6%, p=0.313, not statistically significant). We developed a more patient and therapist-friendly TBI treatment technique that utilizes single-step optimized VMAT plans. It was found that this technique was dosimetrically equivalent to our previous lateral technique in terms of coverage and statistically superior in terms of reduced lung dose.

Sci-Thur PM - Colourful Interactions: Highlights 08: ARC TBI using Single-Step Optimized VMAT Fields

Energy Technology Data Exchange (ETDEWEB)

Hudson, Alana; Gordon, Deborah; Moore, Roseanne; Balogh, Alex; Pierce, Greg [Tom Baker Cancer Centre (Canada)

2016-08-15

Purpose: This work outlines a new TBI delivery technique to replace a lateral POP full bolus technique. The new technique is done with VMAT arc delivery, without bolus, treating the patient prone and supine. The benefits of the arc technique include: increased patient experience and safety, better dose conformity, better organ at risk sparing, decreased therapist time and reduction of therapist injuries. Methods: In this work we build on a technique developed by Jahnke et al. We use standard arc fields with gantry speeds corrected for varying distance to the patient followed by a single step VMAT optimization on a patient CT to increase dose inhomogeneity and to reduce dose to the lungs (vs. blocks). To compare the arc TBI technique to our full bolus technique, we produced plans on patient CTs for both techniques and evaluated several dosimetric parameters using an ANOVA test. Results and Conclusions: The arc technique is able reduce both the hot areas to the body (D2% reduced from 122.2% to 111.8% p<0.01) and the lungs (mean lung dose reduced from 107.5% to 99.1%, p<0.01), both statistically significant, while maintaining coverage (D98% = 97.8% vs. 94.6%, p=0.313, not statistically significant). We developed a more patient and therapist-friendly TBI treatment technique that utilizes single-step optimized VMAT plans. It was found that this technique was dosimetrically equivalent to our previous lateral technique in terms of coverage and statistically superior in terms of reduced lung dose.

Valuing Euro rating-triggered step-up telecom bonds

NARCIS (Netherlands)

P. Houweling (Patrick); A.A. Mentink; A.C.F. Vorst (Ton)

2003-01-01

textabstractWe value rating-triggered step-up bonds with three methods: (i) the Jarrow, Lando and Turnbull (1997, JLT) framework, (ii) a similar framework using historical probabilities and (iii) as plain vanilla bonds. We find that the market seems to value single step-up bonds according to the JLT

Valuing Euro Rating-Triggered Step-Up Telecom Bonds

NARCIS (Netherlands)

P. Houweling (Patrick); A.A. Mentink; A.C.F. Vorst (Ton)

2003-01-01

textabstractWe value rating-triggered step-up bonds with three methods: (i) the Jarrow, Lando and Turnbull (1997, JLT) framework, (ii) a similar framework using historical probabilities and (iii) as plain vanilla bonds. We find that the market seems to value single step-up bonds according to the JLT

Single-Step Fabrication of High-Density Microdroplet Arrays of Low-Surface-Tension Liquids.

Science.gov (United States)

Feng, Wenqian; Li, Linxian; Du, Xin; Welle, Alexander; Levkin, Pavel A

2016-04-01

A facile approach for surface patterning that enables single-step fabrication of high-density arrays of low-surface-tension organic-liquid microdroplets is described. This approach enables miniaturized and parallel high-throughput screenings in organic solvents, formation of homogeneous arrays of hydrophobic nanoparticles, polymer micropads of specific shapes, and polymer microlens arrays. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Low-field multi-step magnetization of GaV4S8 single crystal

Energy Technology Data Exchange (ETDEWEB)

Nakamura, H; Kajinami, Y; Tabata, Y [Department of Materials Science and Engineering, Kyoto University, Kyoto 606-8501 (Japan); Ikeno, R; Motoyama, G; Kohara, T, E-mail: h.nakamura@ht8.ecs.kyoto-u.ac.j [Graduate School of Material Science, University of Hyogo, Kamigori, Hyogo 678-1297 (Japan)

2009-01-01

The magnetization process of single crystalline GaV4S8 including tetrahedral magnetic clusters was measured in the magnetically ordered state below T{sub C} {approx_equal} 13 K. Just below TC, steps were observed at very low fields of the order of 100 Oe, suggesting the competition of several intra- and inter-cluster interactions in a low energy range.

Diffusion welding. [heat treatment of nickel alloys following single step vacuum welding process

Science.gov (United States)

Holko, K. H. (Inventor)

1974-01-01

Dispersion-strengthened nickel alloys are sanded on one side and chemically polished. This is followed by a single-step welding process wherein the polished surfaces are forced into intimate contact at 1,400 F for one hour in a vacuum. Diffusion, recrystallization, and grain growth across the original weld interface are obtained during postheating at 2,150 F for two hours in hydrogen.

Single-step colloidal quantum dot films for infrared solar harvesting

KAUST Repository

Kiani, Amirreza

2016-11-01

Semiconductors with bandgaps in the near- to mid-infrared can harvest solar light that is otherwise wasted by conventional single-junction solar cell architectures. In particular, colloidal quantum dots (CQDs) are promising materials since they are cost-effective, processed from solution, and have a bandgap that can be tuned into the infrared (IR) via the quantum size effect. These characteristics enable them to harvest the infrared portion of the solar spectrum to which silicon is transparent. To date, IR CQD solar cells have been made using a wasteful and complex sequential layer-by-layer process. Here, we demonstrate ∼1 eV bandgap solar-harvesting CQD films deposited in a single step. By engineering a fast-drying solvent mixture for metal iodide-capped CQDs, we deposited active layers greater than 200 nm in thickness having a mean roughness less than 1 nm. We integrated these films into infrared solar cells that are stable in air and exhibit power conversion efficiencies of 3.5% under illumination by the full solar spectrum, and 0.4% through a simulated silicon solar cell filter.

The Technique of Changing the Drive Method of Micro Step Drive and Sensorless Drive for Hybrid Stepping Motor

Science.gov (United States)

Yoneda, Makoto; Dohmeki, Hideo

The position control system with the advantage large torque, low vibration, and high resolution can be obtained by the constant current micro step drive applied to hybrid stepping motor. However loss is large, in order not to be concerned with load torque but to control current uniformly. As the one technique of a position control system in which high efficiency is realizable, the same sensorless control as a permanent magnet motor is effective. But, it was the purpose that the control method proposed until now controls speed. Then, this paper proposed changing the drive method of micro step drive and sensorless drive. The change of the drive method was verified from the simulation and the experiment. On no load, it was checked not producing change of a large speed at the time of a change by making electrical angle and carrying out zero reset of the integrator. On load, it was checked that a large speed change arose. The proposed system could change drive method by setting up the initial value of an integrator using the estimated result, without producing speed change. With this technique, the low loss position control system, which employed the advantage of the hybrid stepping motor, has been built.

Bridge flap technique as a single-step solution to mucogingival problems: A case series

Directory of Open Access Journals (Sweden)

Vivek Gupta

2011-01-01

Full Text Available Shallow vestibule, gingival recession, inadequate width of attached gingiva (AG and aberrant frenum pull are an array of mucogingival problems for which several independent and effective surgical solutions are reported in the literature. This case series reports the effectiveness of the bridge flap technique as a single-step surgical entity for increasing the depth of the vestibule, root coverage, increasing the width of the AG and solving the problem of abnormal frenum pull. Eight patients with 18 teeth altogether having Millers class I, II or III recession along with problems of shallow vestibule, inadequate width of AG and with or without frenum pull underwent this surgical procedure and were followed-up till 9 months post-operatively. The mean root coverage obtained was 55% and the mean average gain in width of the AG was 3.5 mm. The mean percentage gain in clinical attachment level was 41%. The bridge flap technique can be an effective single-step solution for the aforementioned mucogingival problems if present simultaneously in any case, and offers considerable advantages over other mucogingival surgical techniques in terms of simplicity, limited chair-time for the patient and the operator, single surgical intervention for manifold mucogingival problems and low morbidity because of the absence of palatal donor tissue.

A simple and rapid method for high-resolution visualization of single-ion tracks

Directory of Open Access Journals (Sweden)

Masaaki Omichi

2014-11-01

Full Text Available Prompt determination of spatial points of single-ion tracks plays a key role in high-energy particle induced-cancer therapy and gene/plant mutations. In this study, a simple method for the high-resolution visualization of single-ion tracks without etching was developed through the use of polyacrylic acid (PAA-N, N’-methylene bisacrylamide (MBAAm blend films. One of the steps of the proposed method includes exposure of the irradiated films to water vapor for several minutes. Water vapor was found to promote the cross-linking reaction of PAA and MBAAm to form a bulky cross-linked structure; the ion-track scars were detectable at a nanometer scale by atomic force microscopy. This study demonstrated that each scar is easily distinguishable, and the amount of generated radicals of the ion tracks can be estimated by measuring the height of the scars, even in highly dense ion tracks. This method is suitable for the visualization of the penumbra region in a single-ion track with a high spatial resolution of 50 nm, which is sufficiently small to confirm that a single ion hits a cell nucleus with a size ranging between 5 and 20 μm.

A simple and rapid method for high-resolution visualization of single-ion tracks

Energy Technology Data Exchange (ETDEWEB)

Omichi, Masaaki [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan); Center for Collaborative Research, Anan National College of Technology, Anan, Tokushima 774-0017 (Japan); Choi, Wookjin; Sakamaki, Daisuke; Seki, Shu, E-mail: seki@chem.eng.osaka-u.ac.jp [Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Osaka 565-0871 (Japan); Tsukuda, Satoshi [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Miyagi 980-8577 (Japan); Sugimoto, Masaki [Japan Atomic Energy Agency, Takasaki Advanced Radiation Research Institute, Gunma, Gunma 370-1292 (Japan)

2014-11-15

Prompt determination of spatial points of single-ion tracks plays a key role in high-energy particle induced-cancer therapy and gene/plant mutations. In this study, a simple method for the high-resolution visualization of single-ion tracks without etching was developed through the use of polyacrylic acid (PAA)-N, N’-methylene bisacrylamide (MBAAm) blend films. One of the steps of the proposed method includes exposure of the irradiated films to water vapor for several minutes. Water vapor was found to promote the cross-linking reaction of PAA and MBAAm to form a bulky cross-linked structure; the ion-track scars were detectable at a nanometer scale by atomic force microscopy. This study demonstrated that each scar is easily distinguishable, and the amount of generated radicals of the ion tracks can be estimated by measuring the height of the scars, even in highly dense ion tracks. This method is suitable for the visualization of the penumbra region in a single-ion track with a high spatial resolution of 50 nm, which is sufficiently small to confirm that a single ion hits a cell nucleus with a size ranging between 5 and 20 μm.

Incorporation of causative quantitative trait nucleotides in single-step GBLUP.

Science.gov (United States)

Fragomeni, Breno O; Lourenco, Daniela A L; Masuda, Yutaka; Legarra, Andres; Misztal, Ignacy

2017-07-26

Much effort is put into identifying causative quantitative trait nucleotides (QTN) in animal breeding, empowered by the availability of dense single nucleotide polymorphism (SNP) information. Genomic selection using traditional SNP information is easily implemented for any number of genotyped individuals using single-step genomic best linear unbiased predictor (ssGBLUP) with the algorithm for proven and young (APY). Our aim was to investigate whether ssGBLUP is useful for genomic prediction when some or all QTN are known. Simulations included 180,000 animals across 11 generations. Phenotypes were available for all animals in generations 6 to 10. Genotypes for 60,000 SNPs across 10 chromosomes were available for 29,000 individuals. The genetic variance was fully accounted for by 100 or 1000 biallelic QTN. Raw genomic relationship matrices (GRM) were computed from (a) unweighted SNPs, (b) unweighted SNPs and causative QTN, (c) SNPs and causative QTN weighted with results obtained with genome-wide association studies, (d) unweighted SNPs and causative QTN with simulated weights, (e) only unweighted causative QTN, (f-h) as in (b-d) but using only the top 10% causative QTN, and (i) using only causative QTN with simulated weight. Predictions were computed by pedigree-based BLUP (PBLUP) and ssGBLUP. Raw GRM were blended with 1 or 5% of the numerator relationship matrix, or 1% of the identity matrix. Inverses of GRM were obtained directly or with APY. Accuracy of breeding values for 5000 genotyped animals in the last generation with PBLUP was 0.32, and for ssGBLUP it increased to 0.49 with an unweighted GRM, 0.53 after adding unweighted QTN, 0.63 when QTN weights were estimated, and 0.89 when QTN weights were based on true effects known from the simulation. When the GRM was constructed from causative QTN only, accuracy was 0.95 and 0.99 with blending at 5 and 1%, respectively. Accuracies simulating 1000 QTN were generally lower, with a similar trend. Accuracies using the

Improved Full-Newton Step O(nL) Infeasible Interior-Point Method for Linear Optimization

NARCIS (Netherlands)

Gu, G.; Mansouri, H.; Zangiabadi, M.; Bai, Y.Q.; Roos, C.

2009-01-01

We present several improvements of the full-Newton step infeasible interior-point method for linear optimization introduced by Roos (SIAM J. Optim. 16(4):1110–1136, 2006). Each main step of the method consists of a feasibility step and several centering steps. We use a more natural feasibility step,

Single-step preparation of TiO2/MWCNT Nanohybrid materials by laser pyrolysis and application to efficient photovoltaic energy conversion.

Science.gov (United States)

Wang, Jin; Lin, Yaochen; Pinault, Mathieu; Filoramo, Arianna; Fabert, Marc; Ratier, Bernard; Bouclé, Johann; Herlin-Boime, Nathalie

2015-01-14

This paper presents the continuous-flowand single-step synthesis of a TiO2/MWCNT (multiwall carbon nanotubes) nanohybrid material. The synthesis method allows achieving high coverage and intimate interface between the TiO2particles and MWCNTs, together with a highly homogeneous distribution of nanotubes within the oxide. Such materials used as active layer in theporous photoelectrode of solid-state dye-sensitized solar cells leads to a substantial performance improvement (20%) as compared to reference devices.

Comparing Multi-Step IMAC and Multi-Step TiO2 Methods for Phosphopeptide Enrichment

Science.gov (United States)

Yue, Xiaoshan; Schunter, Alissa; Hummon, Amanda B.

2016-01-01

Phosphopeptide enrichment from complicated peptide mixtures is an essential step for mass spectrometry-based phosphoproteomic studies to reduce sample complexity and ionization suppression effects. Typical methods for enriching phosphopeptides include immobilized metal affinity chromatography (IMAC) or titanium dioxide (TiO2) beads, which have selective affinity and can interact with phosphopeptides. In this study, the IMAC enrichment method was compared with the TiO2 enrichment method, using a multi-step enrichment strategy from whole cell lysate, to evaluate their abilities to enrich for different types of phosphopeptides. The peptide-to-beads ratios were optimized for both IMAC and TiO2 beads. Both IMAC and TiO2 enrichments were performed for three rounds to enable the maximum extraction of phosphopeptides from the whole cell lysates. The phosphopeptides that are unique to IMAC enrichment, unique to TiO2 enrichment, and identified with both IMAC and TiO2 enrichment were analyzed for their characteristics. Both IMAC and TiO2 enriched similar amounts of phosphopeptides with comparable enrichment efficiency. However, phosphopeptides that are unique to IMAC enrichment showed a higher percentage of multi-phosphopeptides, as well as a higher percentage of longer, basic, and hydrophilic phosphopeptides. Also, the IMAC and TiO2 procedures clearly enriched phosphopeptides with different motifs. Finally, further enriching with two rounds of TiO2 from the supernatant after IMAC enrichment, or further enriching with two rounds of IMAC from the supernatant TiO2 enrichment does not fully recover the phosphopeptides that are not identified with the corresponding multi-step enrichment. PMID:26237447

Single-step syngas-to-distillates (S2D) process based on biomass-derived syngas--a techno-economic analysis.

Science.gov (United States)

Zhu, Yunhua; Jones, Susanne B; Biddy, Mary J; Dagle, Robert A; Palo, Daniel R

2012-08-01

This study compared biomass gasification based syngas-to-distillate (S2D) systems using techno-economic analysis (TEA). Three cases, state of technology (SOT), goal, and conventional, were compared in terms of performance and cost. The SOT case represented the best available experimental results for a process starting with syngas using a single-step dual-catalyst reactor for distillate generation. The conventional case mirrored a conventional two-step S2D process consisting of separate syngas-to-methanol and methanol-to-gasoline (MTG) processes. The goal case assumed the same performance as the conventional, but with a single-step S2D technology. TEA results revealed that the SOT was more expensive than the conventional and goal cases. The SOT case suffers from low one-pass yield and high selectivity to light hydrocarbons, both of which drive up production cost. Sensitivity analysis indicated that light hydrocarbon yield and single pass conversion efficiency were the key factors driving the high cost for the SOT case. Copyright © 2012 Elsevier Ltd. All rights reserved.

Towards Single-Step Biofabrication of Organs on a Chip via 3D Printing.

Science.gov (United States)

Knowlton, Stephanie; Yenilmez, Bekir; Tasoglu, Savas

2016-09-01

Organ-on-a-chip engineering employs microfabrication of living tissues within microscale fluid channels to create constructs that closely mimic human organs. With the advent of 3D printing, we predict that single-step fabrication of these devices will enable rapid design and cost-effective iterations in the development stage, facilitating rapid innovation in this field. Copyright © 2016 Elsevier Ltd. All rights reserved.

A two-step Hilbert transform method for 2D image reconstruction

International Nuclear Information System (INIS)

Noo, Frederic; Clackdoyle, Rolf; Pack, Jed D

2004-01-01

The paper describes a new accurate two-dimensional (2D) image reconstruction method consisting of two steps. In the first step, the backprojected image is formed after taking the derivative of the parallel projection data. In the second step, a Hilbert filtering is applied along certain lines in the differentiated backprojection (DBP) image. Formulae for performing the DBP step in fan-beam geometry are also presented. The advantage of this two-step Hilbert transform approach is that in certain situations, regions of interest (ROIs) can be reconstructed from truncated projection data. Simulation results are presented that illustrate very similar reconstructed image quality using the new method compared to standard filtered backprojection, and that show the capability to correctly handle truncated projections. In particular, a simulation is presented of a wide patient whose projections are truncated laterally yet for which highly accurate ROI reconstruction is obtained

Quartz-Seq2: a high-throughput single-cell RNA-sequencing method that effectively uses limited sequence reads.

Science.gov (United States)

Sasagawa, Yohei; Danno, Hiroki; Takada, Hitomi; Ebisawa, Masashi; Tanaka, Kaori; Hayashi, Tetsutaro; Kurisaki, Akira; Nikaido, Itoshi

2018-03-09

High-throughput single-cell RNA-seq methods assign limited unique molecular identifier (UMI) counts as gene expression values to single cells from shallow sequence reads and detect limited gene counts. We thus developed a high-throughput single-cell RNA-seq method, Quartz-Seq2, to overcome these issues. Our improvements in the reaction steps make it possible to effectively convert initial reads to UMI counts, at a rate of 30-50%, and detect more genes. To demonstrate the power of Quartz-Seq2, we analyzed approximately 10,000 transcriptomes from in vitro embryonic stem cells and an in vivo stromal vascular fraction with a limited number of reads.

Stability of one-step methods in transient nonlinear heat conduction

International Nuclear Information System (INIS)

Hughes, J.R.

1977-01-01

The purpose of the present work is to ascertain practical stability conditions for one-step methods commonly used in transient nonlinear heat conduction analyses. The class of problems considered is governed by a temporally continuous, spatially discrete system involving the capacity matrix C, conductivity matrix K, heat supply vector, temperature vector and time differenciation. In the linear case, in which K and C are constant, the stability behavior of one-step methods is well known. But in this paper the concepts of stability, appropriate to the nonlinear problem, are thoroughly discussed. They of course reduce to the usual stability criterion for the linear, constant coefficient case. However, for nonlinear problems there are differences and these ideas are of key importance in obtaining practical stability conditions. Of particular importance is a recent result which indicates that, in a sense, the trapezoidal and midpoint families are quivalent. Thus, stability results for one family may be translated into a result for the other. The main results obtained are summarized as follows. The stability behavior of the explicit Euler method in the nonlinear regime is analogous to that for linear problems. In particular, an a priori step size restriction may be determined for each time step. The precise time step restriction on implicit conditionally stable members of the trapezoidal and midpoint families is shown not to be determinable a priori. Of considerable practical significance, unconditionally stable members of the trapezoidal and midpoint families are identified

A two-step leaching method designed based on chemical fraction distribution of the heavy metals for selective leaching of Cd, Zn, Cu, and Pb from metallurgical sludge.

Science.gov (United States)

Wang, Fen; Yu, Junxia; Xiong, Wanli; Xu, Yuanlai; Chi, Ru-An

2018-01-01

For selective leaching and highly effective recovery of heavy metals from a metallurgical sludge, a two-step leaching method was designed based on the distribution analysis of the chemical fractions of the loaded heavy metal. Hydrochloric acid (HCl) was used as a leaching agent in the first step to leach the relatively labile heavy metals and then ethylenediamine tetraacetic acid (EDTA) was applied to leach the residual metals according to their different fractional distribution. Using the two-step leaching method, 82.89% of Cd, 55.73% of Zn, 10.85% of Cu, and 0.25% of Pb were leached in the first step by 0.7 M HCl at a contact time of 240 min, and the leaching efficiencies for Cd, Zn, Cu, and Pb were elevated up to 99.76, 91.41, 71.85, and 94.06%, by subsequent treatment with 0.2 M EDTA at 480 min, respectively. Furthermore, HCl leaching induced fractional redistribution, which might increase the mobility of the remaining metals and then facilitate the following metal removal by EDTA. The facilitation was further confirmed by the comparison to the one-step leaching method with single HCl or single EDTA, respectively. These results suggested that the designed two-step leaching method by HCl and EDTA could be used for selective leaching and effective recovery of heavy metals from the metallurgical sludge or heavy metal-contaminated solid media.

A high-yield, one-step synthesis of surfactant-free gold nanostars and numerical study for single-molecule SERS application

Energy Technology Data Exchange (ETDEWEB)

Chatterjee, S.; Ringane, A. B.; Arya, A.; Das, G. M.; Dantham, V. R., E-mail: dantham@iitp.ac.in; Laha, R. [Indian Institute of Technology Patna, Department of Physics (India); Hussian, S. [Indian Institute of Technology Patna, Department of Chemistry (India)

2016-08-15

We report a high-yield synthesis of star-shaped gold nanostructures in one step, using a new surfactant-free wet chemistry method. Compared to the existing reports, these nanostars were found to have longer and sharper spikes anchored uniformly on the surface of the spherical core, allowing at least a few hot spots irrespective of the incident light polarization. The average experimental values of core radius and spike length were found to be 88.5 and 72 nm, respectively. Using these values in numerical simulations, the local electric field enhancement (η) and localized surface plasmon resonance (LSPR) spectrum were obtained. Moreover, the single-molecule surface-enhanced Raman scattering (SERS) enhancement factor was found to vary from 10{sup 10} to 10{sup 13} depending on the excitation wavelengths. Our theoretical calculations suggest that these nanostructures can be used to fabricate efficient SERS-based biosensors for the detection of single molecules in real time and for predicting structural information of single molecules.

Single-step laser-based fabrication and patterning of cell-encapsulated alginate microbeads

International Nuclear Information System (INIS)

Kingsley, D M; Dias, A D; Corr, D T; Chrisey, D B

2013-01-01

Alginate can be used to encapsulate mammalian cells and for the slow release of small molecules. Packaging alginate as microbead structures allows customizable delivery for tissue engineering, drug release, or contrast agents for imaging. However, state-of-the-art microbead fabrication has a limited range in achievable bead sizes, and poor control over bead placement, which may be desired to localize cellular signaling or delivery. Herein, we present a novel, laser-based method for single-step fabrication and precise planar placement of alginate microbeads. Our results show that bead size is controllable within 8%, and fabricated microbeads can remain immobilized within 2% of their target placement. Demonstration of this technique using human breast cancer cells shows that cells encapsulated within these microbeads survive at a rate of 89.6%, decreasing to 84.3% after five days in culture. Infusing rhodamine dye into microbeads prior to fluorescent microscopy shows their 3D spheroidal geometry and the ability to sequester small molecules. Microbead fabrication and patterning is compatible with conventional cellular transfer and patterning by laser direct-write, allowing location-based cellular studies. While this method can also be used to fabricate microbeads en masse for collection, the greatest value to tissue engineering and drug delivery studies and applications lies in the pattern registry of printed microbeads. (paper)

Comparison of the Screening Tests for Gestational Diabetes Mellitus between "One-Step" and "Two-Step" Methods among Thai Pregnant Women.

Science.gov (United States)

Luewan, Suchaya; Bootchaingam, Phenphan; Tongsong, Theera

2018-01-01

To compare the prevalence and pregnancy outcomes of GDM between those screened by the "one-step" (75 gm GTT) and "two-step" (100 gm GTT) methods. A prospective study was conducted on singleton pregnancies at low or average risk of GDM. All were screened between 24 and 28 weeks, using the one-step or two-step method based on patients' preference. The primary outcome was prevalence of GDM, and secondary outcomes included birthweight, gestational age, rates of preterm birth, small/large-for-gestational age, low Apgar scores, cesarean section, and pregnancy-induced hypertension. A total of 648 women were screened: 278 in the one-step group and 370 in the two-step group. The prevalence of GDM was significantly higher in the one-step group; 32.0% versus 10.3%. Baseline characteristics and pregnancy outcomes in both groups were comparable. However, mean birthweight was significantly higher among pregnancies with GDM diagnosed by the two-step approach (3204 ± 555 versus 3009 ± 666 g; p =0.022). Likewise, the rate of large-for-date tended to be higher in the two-step group, but was not significant. The one-step approach is associated with very high prevalence of GDM among Thai population, without clear evidence of better outcomes. Thus, this approach may not be appropriate for screening in a busy antenatal care clinic like our setting or other centers in developing countries.

Improved Full-Newton Step O(nL) Infeasible Interior-Point Method for Linear Optimization

OpenAIRE

Gu, G.; Mansouri, H.; Zangiabadi, M.; Bai, Y.Q.; Roos, C.

2009-01-01

We present several improvements of the full-Newton step infeasible interior-point method for linear optimization introduced by Roos (SIAM J. Optim. 16(4):1110–1136, 2006). Each main step of the method consists of a feasibility step and several centering steps. We use a more natural feasibility step, which targets the ?+-center of the next pair of perturbed problems. As for the centering steps, we apply a sharper quadratic convergence result, which leads to a slightly wider neighborhood for th...

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

W. J. Galyean; A. M. Whaley; D. L. Kelly; R. L. Boring

2011-05-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

SPAR-H Step-by-Step Guidance

International Nuclear Information System (INIS)

Galyean, W.J.; Whaley, A.M.; Kelly, D.L.; Boring, R.L.

2011-01-01

This guide provides step-by-step guidance on the use of the SPAR-H method for quantifying Human Failure Events (HFEs). This guide is intended to be used with the worksheets provided in: 'The SPAR-H Human Reliability Analysis Method,' NUREG/CR-6883, dated August 2005. Each step in the process of producing a Human Error Probability (HEP) is discussed. These steps are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff. The discussions on dependence are extensive and include an appendix that describes insights obtained from the psychology literature.

Single Laboratory Validated Method for Determination of Cylindrospermopsin and Anatoxin-a in Ambient Water by Liquid Chromatography/ Tandem Mass Spectrometry (LC/MS/MS)

Science.gov (United States)

This product is an LC/MS/MS single laboratory validated method for the determination of cylindrospermopsin and anatoxin-a in ambient waters. The product contains step-by-step instructions for sample preparation, analyses, preservation, sample holding time and QC protocols to ensu...

Q-Step methods for Newton-Jacobi operator equation | Uwasmusi ...

African Journals Online (AJOL)

The paper considers the Newton-Jacobi operator equation for the solution of nonlinear systems of equations. Special attention is paid to the computational part of this method with particular reference to the q-step methods. Journal of the Nigerian Association of Mathematical Physics Vol. 8 2004: pp. 237-241 ...

Binary Factorization in Hopfield-Like Neural Networks: Single-Step Approximation and Computer Simulations

Czech Academy of Sciences Publication Activity Database

Frolov, A. A.; Sirota, A.M.; Húsek, Dušan; Muraviev, I. P.

2004-01-01

Roč. 14, č. 2 (2004), s. 139-152 ISSN 1210-0552 R&D Projects: GA ČR GA201/01/1192 Grant - others:BARRANDE(EU) 99010-2/99053; Intellectual computer Systems(EU) Grant 2.45 Institutional research plan: CEZ:AV0Z1030915 Keywords : nonlinear binary factor analysis * feature extraction * recurrent neural network * Single-Step approximation * neurodynamics simulation * attraction basins * Hebbian learning * unsupervised learning * neuroscience * brain function modeling Subject RIV: BA - General Mathematics

Microwave-assisted one-step synthesis of acetate-capped NaYF4

DEFF Research Database (Denmark)

Reddy, Kumbam Lingeshwar; Prabhakar, Neeraj; Arppe, Riikka

2017-01-01

Acetate-capped hydrophilic cubic phase NaYF4:Yb/Er upconversion nanophosphors were effectively synthesized in a single step employing a facile microwave-assisted synthesis route by applying relatively low temperatures in a short span of time compared to the conventional synthetic methods. The nan......Acetate-capped hydrophilic cubic phase NaYF4:Yb/Er upconversion nanophosphors were effectively synthesized in a single step employing a facile microwave-assisted synthesis route by applying relatively low temperatures in a short span of time compared to the conventional synthetic methods...

Blastocyst utilization rates after continuous culture in two commercial single-step media: a prospective randomized study with sibling oocytes.

Science.gov (United States)

Sfontouris, Ioannis A; Kolibianakis, Efstratios M; Lainas, George T; Venetis, Christos A; Petsas, George K; Tarlatzis, Basil C; Lainas, Tryfon G

2017-10-01

The aim of this study is to determine whether blastocyst utilization rates are different after continuous culture in two different commercial single-step media. This is a paired randomized controlled trial with sibling oocytes conducted in infertility patients, aged ≤40 years with ≥10 oocytes retrieved assigned to blastocyst culture and transfer. Retrieved oocytes were randomly allocated to continuous culture in either Sage one-step medium (Origio) or Continuous Single Culture (CSC) medium (Irvine Scientific) without medium renewal up to day 5 post oocyte retrieval. Main outcome measure was the proportion of embryos suitable for clinical use (utilization rate). A total of 502 oocytes from 33 women were randomly allocated to continuous culture in either Sage one-step medium (n = 250) or CSC medium (n = 252). Fertilization was performed by either in vitro fertilization or intracytoplasmic sperm injection, and embryo transfers were performed on day 5. Two patients had all blastocysts frozen due to the occurrence of severe ovarian hyperstimulation syndrome. Fertilization and cleavage rates, as well as embryo quality on day 3, were similar in the two media. Blastocyst utilization rates (%, 95% CI) [55.4% (46.4-64.1) vs 54.7% (44.9-64.6), p = 0.717], blastocyst formation rates [53.6% (44.6-62.5) vs 51.9 (42.2-61.6), p = 0.755], and proportion of good quality blastocysts [36.8% (28.1-45.4) vs 36.1% (27.2-45.0), p = 0.850] were similar in Sage one-step and CSC media, respectively. Continuous culture of embryos in Sage one-step and CSC media is associated with similar blastocyst development and utilization rates. Both single-step media appear to provide adequate support during in vitro preimplantation embryo development. Whether these observations are also valid for other continuous single medium protocols remains to be determined. NCT02302638.

The effect of a cognitive-motor intervention on voluntary step execution under single and dual task conditions in older adults: a randomized controlled pilot study

Directory of Open Access Journals (Sweden)

Pichierri G

2012-07-01

Full Text Available Giuseppe Pichierri,1 Amos Coppe,1 Silvio Lorenzetti,2 Kurt Murer,1 Eling D de Bruin11Institute of Human Movement Sciences and Sport, Department of Health Sciences and Technology, ETH Zurich, Switzerland; 2Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zurich, SwitzerlandBackground: This randomized controlled pilot study aimed to explore whether a cognitive-motor exercise program that combines traditional physical exercise with dance video gaming can improve the voluntary stepping responses of older adults under attention demanding dual task conditions.Methods: Elderly subjects received twice weekly cognitive-motor exercise that included progressive strength and balance training supplemented by dance video gaming for 12 weeks (intervention group. The control group received no specific intervention. Voluntary step execution under single and dual task conditions was recorded at baseline and post intervention (Week 12.Results: After intervention between-group comparison revealed significant differences for initiation time of forward steps under dual task conditions (U = 9, P = 0.034, r = 0.55 and backward steps under dual task conditions (U = 10, P = 0.045, r = 0.52 in favor of the intervention group, showing altered stepping levels in the intervention group compared to the control group.Conclusion: A cognitive-motor intervention based on strength and balance exercises with additional dance video gaming is able to improve voluntary step execution under both single and dual task conditions in older adults.Keywords: fall prevention, exercise, dance, video game

Real-time, single-step bioassay using nanoplasmonic resonator with ultra-high sensitivity

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xiang; Ellman, Jonathan A; Chen, Fanqing Frank; Su, Kai-Hang; Wei, Qi-Huo; Sun, Cheng

2014-04-01

A nanoplasmonic resonator (NPR) comprising a metallic nanodisk with alternating shielding layer(s), having a tagged biomolecule conjugated or tethered to the surface of the nanoplasmonic resonator for highly sensitive measurement of enzymatic activity. NPRs enhance Raman signals in a highly reproducible manner, enabling fast detection of protease and enzyme activity, such as Prostate Specific Antigen (paPSA), in real-time, at picomolar sensitivity levels. Experiments on extracellular fluid (ECF) from paPSA-positive cells demonstrate specific detection in a complex bio-fluid background in real-time single-step detection in very small sample volumes.

some generalized two-step block hybrid numerov method for solving ...

African Journals Online (AJOL)

Nwokem et al.

ABSTRACT. This paper proposes a class of generalized two-step Numerov methods, a block hybrid type for the direct solution of general second order ordinary differential equations. Both the main method and additional methods were derived via interpolation and collocation procedures. The basic properties of zero ...

A GPU-accelerated semi-implicit fractional step method for numerical solutions of incompressible Navier-Stokes equations

Science.gov (United States)

Ha, Sanghyun; Park, Junshin; You, Donghyun

2017-11-01

Utility of the computational power of modern Graphics Processing Units (GPUs) is elaborated for solutions of incompressible Navier-Stokes equations which are integrated using a semi-implicit fractional-step method. Due to its serial and bandwidth-bound nature, the present choice of numerical methods is considered to be a good candidate for evaluating the potential of GPUs for solving Navier-Stokes equations using non-explicit time integration. An efficient algorithm is presented for GPU acceleration of the Alternating Direction Implicit (ADI) and the Fourier-transform-based direct solution method used in the semi-implicit fractional-step method. OpenMP is employed for concurrent collection of turbulence statistics on a CPU while Navier-Stokes equations are computed on a GPU. Extension to multiple NVIDIA GPUs is implemented using NVLink supported by the Pascal architecture. Performance of the present method is experimented on multiple Tesla P100 GPUs compared with a single-core Xeon E5-2650 v4 CPU in simulations of boundary-layer flow over a flat plate. Supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (Ministry of Science, ICT and Future Planning NRF-2016R1E1A2A01939553, NRF-2014R1A2A1A11049599, and Ministry of Trade, Industry and Energy 201611101000230).

Single step synthesis of GdAlO3 powder

International Nuclear Information System (INIS)

Sinha, Amit; Nair, S.R.; Sinha, P.K.

2011-01-01

Research highlights: → First report on direct formation of GdAlO 3 powder using a novel combustion process. → Study of combustion characteristics of Gd(NO 3 ) 3 and Al(NO 3 ) 3 towards three fuels. → Preparation of highly sinterable GdAlO 3 powders through fuel-mixture approach. → Significant reduction in energy consumption for production of GdAlO 3 sintered body. - Abstract: A novel method for preparation of nano-crystalline gadolinium aluminate (GdAlO 3 ) powder, based on combustion synthesis, is reported. It was observed that aluminium nitrate and gadolinium nitrate exhibit different combustion characteristics with respect to urea, glycine and β-alanine. While urea was proven to be a suitable fuel for direct formation of crystalline α-Al 2 O 3 from its nitrate, glycine and β-alanine are suitable fuels for gadolinium nitrate for preparation of its oxide after combustion reaction. Based on the observed chemical characteristics of gadolinium and aluminium nitrates with respect to above mentioned fuels for the combustion reaction, the fuel mixture composition could be predicted that could lead to phase pure perovskite GdAlO 3 directly after the combustion reaction without any subsequent calcination step. The use of single fuel, on the other hand, leads to formation of amorphous precursor powders that call for subsequent calcination for the formation of crystalline GdAlO 3 . The powders produced directly after combustion reactions using fuel mixtures were found to be highly sinterable. The sintering of the powders at 1550 o C for 4 h resulted in GdAlO 3 with sintered density of more than 95%. T.D.

Single step thermal decomposition approach to prepare supported γ-Fe2O3 nanoparticles

International Nuclear Information System (INIS)

Sharma, Geetu; Jeevanandam, P.

2012-01-01

γ-Fe 2 O 3 nanoparticles supported on MgO (macro-crystalline and nanocrystalline) were prepared by an easy single step thermal decomposition method. Thermal decomposition of iron acetylacetonate in diphenyl ether, in the presence of the supports followed by calcination, leads to iron oxide nanoparticles supported on MgO. The X-ray diffraction results indicate the stability of γ-Fe 2 O 3 phase on MgO (macro-crystalline and nanocrystalline) up to 1150 °C. The scanning electron microscopy images show that the supported iron oxide nanoparticles are agglomerated while the energy dispersive X-ray analysis indicates the presence of iron, magnesium and oxygen in the samples. Transmission electron microscopy images indicate the presence of smaller γ-Fe 2 O 3 nanoparticles on nanocrystalline MgO. The magnetic properties of the supported magnetic nanoparticles at various calcination temperatures (350-1150 °C) were studied using a superconducting quantum interference device which indicates superparamagnetic behavior.

Multiple-time-stepping generalized hybrid Monte Carlo methods

Energy Technology Data Exchange (ETDEWEB)

Escribano, Bruno, E-mail: bescribano@bcamath.org [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); Akhmatskaya, Elena [BCAM—Basque Center for Applied Mathematics, E-48009 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao (Spain); Reich, Sebastian [Universität Potsdam, Institut für Mathematik, D-14469 Potsdam (Germany); Azpiroz, Jon M. [Kimika Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU) and Donostia International Physics Center (DIPC), P.K. 1072, Donostia (Spain)

2015-01-01

Performance of the generalized shadow hybrid Monte Carlo (GSHMC) method [1], which proved to be superior in sampling efficiency over its predecessors [2–4], molecular dynamics and hybrid Monte Carlo, can be further improved by combining it with multi-time-stepping (MTS) and mollification of slow forces. We demonstrate that the comparatively simple modifications of the method not only lead to better performance of GSHMC itself but also allow for beating the best performed methods, which use the similar force splitting schemes. In addition we show that the same ideas can be successfully applied to the conventional generalized hybrid Monte Carlo method (GHMC). The resulting methods, MTS-GHMC and MTS-GSHMC, provide accurate reproduction of thermodynamic and dynamical properties, exact temperature control during simulation and computational robustness and efficiency. MTS-GHMC uses a generalized momentum update to achieve weak stochastic stabilization to the molecular dynamics (MD) integrator. MTS-GSHMC adds the use of a shadow (modified) Hamiltonian to filter the MD trajectories in the HMC scheme. We introduce a new shadow Hamiltonian formulation adapted to force-splitting methods. The use of such Hamiltonians improves the acceptance rate of trajectories and has a strong impact on the sampling efficiency of the method. Both methods were implemented in the open-source MD package ProtoMol and were tested on a water and a protein systems. Results were compared to those obtained using a Langevin Molly (LM) method [5] on the same systems. The test results demonstrate the superiority of the new methods over LM in terms of stability, accuracy and sampling efficiency. This suggests that putting the MTS approach in the framework of hybrid Monte Carlo and using the natural stochasticity offered by the generalized hybrid Monte Carlo lead to improving stability of MTS and allow for achieving larger step sizes in the simulation of complex systems.

Novel One-Step Multiplex PCR-Based Method for HLA Typing and Preimplantational Genetic Diagnosis of -Thalassemia

Directory of Open Access Journals (Sweden)

Raquel M. Fernández

2013-01-01

Full Text Available Preimplantation genetic diagnosis (PGD of single gene disorders, combined with HLA matching (PGD-HLA, has emerged as a tool for couples at risk of transmitting a genetic disease to select unaffected embryos of an HLA tissue type compatible with that of an existing affected child. Here, we present a novel one-step multiplex PCR to genotype a spectrum of STRs to simultaneously perform HLA typing and PGD for -thalassemia. This method is being routinely used for PGD-HLA cycles in our department, with a genotyping success rate of 100%. As an example, we present the first successful PGD-HLA typing in Spain, which resulted in the birth of a boy and subsequent successful HSC transplantation to his affected brother, who is doing well 4 years following transplantation. The advantage of our method is that it involves only a round of single PCR for multiple markers amplification (up to 10 markers within the HLA and 6 markers at the -globin loci. This strategy has allowed us to considerably reduce the optimization of the PCR method for each specific PGD-HLA family as well as the time to obtain molecular results in each cycle.

Using a Three-Step Method in a Calculus Class: Extending the Worked Example

Science.gov (United States)

Miller, David

2010-01-01

This article discusses a three-step method that was used in a college calculus course. The three-step method was developed to help students understand the course material and transition to be more independent learners. In addition, the method helped students to transfer concepts from short-term to long-term memory while lowering cognitive load.…

Spectral filtering modulation method for estimation of hemoglobin concentration and oxygenation based on a single fluorescence emission spectrum in tissue phantoms.

Science.gov (United States)

Liu, Quan; Vo-Dinh, Tuan

2009-10-01

Hemoglobin concentration and oxygenation in tissue are important biomarkers that are useful in both research and clinical diagnostics of a wide variety of diseases such as cancer. The authors aim to develop simple ratiometric method based on the spectral filtering modulation (SFM) of fluorescence spectra to estimate the total hemoglobin concentration and oxygenation in tissue using only a single fluorescence emission spectrum, which will eliminate the need of diffuse reflectance measurements and prolonged data processing as required by most current methods, thus enabling rapid clinical measurements. The proposed method consists of two steps. In the first step, the total hemoglobin concentration is determined by comparing a ratio of fluorescence intensities at two emission wavelengths to a calibration curve. The second step is to estimate oxygen saturation by comparing a double ratio that involves three emission wavelengths to another calibration curve that is a function of oxygen saturation for known total hemoglobin concentration. Theoretical derivation shows that the ratio in the first step is linearly proportional to the total hemoglobin concentrations and the double ratio in the second step is related to both total hemoglobin concentration and hemoglobin oxygenation for the chosen fiber-optic probe geometry. Experiments on synthetic fluorescent tissue phantoms, which included hemoglobin with both constant and varying oxygenation as the absorber, polystyrene spheres as scatterers, and flavin adenine dinucleotide as the fluorophore, were carried out to validate the theoretical prediction. Tissue phantom experiments confirm that the ratio in the first step is linearly proportional to the total hemoglobin concentration and the double ratio in the second step is related to both total hemoglobin concentrations and hemoglobin oxygenation. Furthermore, the relations between the two ratios and the total hemoglobin concentration and hemoglobin oxygenation are insensitive

Linking pedestrian flow characteristics with stepping locomotion

Science.gov (United States)

Wang, Jiayue; Boltes, Maik; Seyfried, Armin; Zhang, Jun; Ziemer, Verena; Weng, Wenguo

2018-06-01

While properties of human traffic flow are described by speed, density and flow, the locomotion of pedestrian is based on steps. To relate characteristics of human locomotor system with properties of human traffic flow, this paper aims to connect gait characteristics like step length, step frequency, swaying amplitude and synchronization with speed and density and thus to build a ground for advanced pedestrian models. For this aim, observational and experimental study on the single-file movement of pedestrians at different densities is conducted. Methods to measure step length, step frequency, swaying amplitude and step synchronization are proposed by means of trajectories of the head. Mathematical models for the relations of step length or frequency and speed are evaluated. The problem how step length and step duration are influenced by factors like body height and density is investigated. It is shown that the effect of body height on step length and step duration changes with density. Furthermore, two different types of step in-phase synchronization between two successive pedestrians are observed and the influence of step synchronization on step length is examined.

Microwave pyrolysis using self-generated pyrolysis gas as activating agent: An innovative single-step approach to convert waste palm shell into activated carbon

Science.gov (United States)

Yek, Peter Nai Yuh; Keey Liew, Rock; Shahril Osman, Mohammad; Chung Wong, Chee; Lam, Su Shiung

2017-11-01

Waste palm shell (WPS) is a biomass residue largely available from palm oil industries. An innovative microwave pyrolysis method was developed to produce biochar from WPS while the pyrolysis gas generated as another product is simultaneously used as activating agent to transform the biochar into waste palm shell activated carbon (WPSAC), thus allowing carbonization and activation to be performed simultaneously in a single-step approach. The pyrolysis method was investigated over a range of process temperature and feedstock amount with emphasis on the yield and composition of the WPSAC obtained. The WPSAC was tested as dye adsorbent in removing methylene blue. This pyrolysis approach provided a fast heating rate (37.5°/min) and short process time (20 min) in transforming WPS into WPSAC, recording a product yield of 40 wt%. The WPSAC was detected with high BET surface area (≥ 1200 m2/g), low ash content (< 5 wt%), and high pore volume (≥ 0.54 cm3/g), thus recording high adsorption efficiency of 440 mg of dye/g. The desirable process features (fast heating rate, short process time) and the recovery of WPSAC suggest the exceptional promise of the single-step microwave pyrolysis approach to produce high-grade WPSAC from WPS.

Electric field dependent paramagnetic defect creation in single step implanted Simox films

International Nuclear Information System (INIS)

Leray, J.L.; Margail, J.

1991-01-01

X irradiation induced oxygen-vacancy defect creation has been studied in SIMOX produced by single step implantation and annealing. It is shown that SIMOX is substantially more radiation sensitive (for these defects) than thermal or bulk oxide. Irradiation in the presence of an electric field 0.5 -1 MV cm -1 is found to enhance the rate of defect creation by ≥ 2 times. Further enhanced defect creation is observed in SIMOX samples whose substrate has been chemically thinned prior to irradiation. This enhancement is attributed to modification of the network induced by hydrogen introduced during the thinning process

Compact Ag@Fe3O4 Core-shell Nanoparticles by Means of Single-step Thermal Decomposition Reaction

Science.gov (United States)

Brollo, Maria Eugênia F.; López-Ruiz, Román; Muraca, Diego; Figueroa, Santiago J. A.; Pirota, Kleber R.; Knobel, Marcelo

2014-10-01

A temperature pause introduced in a simple single-step thermal decomposition of iron, with the presence of silver seeds formed in the same reaction mixture, gives rise to novel compact heterostructures: brick-like Ag@Fe3O4 core-shell nanoparticles. This novel method is relatively easy to implement, and could contribute to overcome the challenge of obtaining a multifunctional heteroparticle in which a noble metal is surrounded by magnetite. Structural analyses of the samples show 4 nm silver nanoparticles wrapped within compact cubic external structures of Fe oxide, with curious rectangular shape. The magnetic properties indicate a near superparamagnetic like behavior with a weak hysteresis at room temperature. The value of the anisotropy involved makes these particles candidates to potential applications in nanomedicine.

Single-Step Generation of Conditional Knockout Mouse Embryonic Stem Cells

Directory of Open Access Journals (Sweden)

Matyas Flemr

2015-07-01

Full Text Available Induction of double-strand DNA breaks (DSBs by engineered nucleases, such as CRISPR/Cas9 or transcription activator-like effector nucleases (TALENs, stimulates knockin of exogenous DNA fragments via homologous recombination (HR. However, the knockin efficiencies reported so far have not allowed more complex in vitro genome modifications such as, for instance, simultaneous integration of a DNA fragment at two distinct genomic sites. We developed a reporter system to enrich for cells with engineered nuclease-assisted HR events. Using this system in mouse embryonic stem cells (mESCs, we achieve single-step biallelic and seamless integration of two loxP sites for Cre recombinase-mediated inducible gene knockout, as well as biallelic endogenous gene tagging with high efficiency. Our approach reduces the time and resources required for conditional knockout mESC generation dramatically.

Stability of one-step methods in transient nonlinear heat conduction

International Nuclear Information System (INIS)

Hughes, J.R.

1977-01-01

The purpose of the present work is to ascertain practical stability conditions for one-step methods commonly used in transient nonlinear heat conduction analyses. In this paper the concepts of stability, appropriate to the nonlinear problem, are thoroughly discussed. They of course reduce to the usual stability critierion for the linear, constant coefficient case. However, for nonlinear problems there are differences and theses ideas are of key importance in obtaining practical stability conditions. Of particular importance is a recent result which indicates that, in a sense, the trapezoidal and midpoint families are equivalent. Thus, stability results for one family may be translated into a result for the other. The main results obtained are: The stability behaviour of the explicit Euler method in the nonlinear regime is analogous to that for linear problems. In particular, an a priori step size restriction may be determined for each time step. The precise time step restriction on implicit conditionally stable members of the trapezoidal and midpoint families is shown not to be determinable a priori. Of considerable practical significance, unconditionally stable members of the trapezoidal and midpoint families are identified. All notions of stability employed are motivated and defined, and their interpretations in practical computing are indicated. (Auth.)

Diffusion tensor imaging fiber tracking with reliable tracking orientation and flexible step size☆

Science.gov (United States)

Yao, Xufeng; Wang, Manning; Chen, Xinrong; Nie, Shengdong; Li, Zhexu; Xu, Xiaoping; Zhang, Xuelong; Song, Zhijian

2013-01-01

We propose a method of reliable tracking orientation and flexible step size fiber tracking. A new directional strategy was defined to select one optimal tracking orientation from each directional set, which was based on the single-tensor model and the two-tensor model. The directional set of planar voxels contained three tracking directions: two from the two-tensor model and one from the single-tensor model. The directional set of linear voxels contained only one principal vector. In addition, a flexible step size, rather than fixable step sizes, was implemented to improve the accuracy of fiber tracking. We used two sets of human data to assess the performance of our method; one was from a healthy volunteer and the other from a patient with low-grade glioma. Results verified that our method was superior to the single-tensor Fiber Assignment by Continuous Tracking and the two-tensor eXtended Streamline Tractography for showing detailed images of fiber bundles. PMID:25206444

Thin film complementary metal oxide semiconductor (CMOS) device using a single-step deposition of the channel layer

KAUST Repository

Nayak, Pradipta K.; Caraveo-Frescas, J. A.; Wang, Zhenwei; Hedhili, Mohamed N.; Wang, Q. X.; Alshareef, Husam N.

2014-01-01

We report, for the first time, the use of a single step deposition of semiconductor channel layer to simultaneously achieve both n-and p-type transport in transparent oxide thin film transistors (TFTs). This effect is achieved by controlling

Detection of protein concentrations using a pH-step titration method

NARCIS (Netherlands)

Kruise, J.; Kruise, J.; Eijkel, Jan C.T.; Bergveld, Piet

1997-01-01

A stimulus-response method based on the application of a pH step is proposed for the detection of protein immobilized in a membrane on top of an ion-sensitive field-effect transistor (ISFET). The ISFET response to a step-wise change in pH, applied at the interface between the membrane and the

Single-step gas phase synthesis of stable iron aluminide nanoparticles with soft magnetic properties

Energy Technology Data Exchange (ETDEWEB)

Vernieres, Jerome, E-mail: Jerome.vernieres@oist.jp; Benelmekki, Maria; Kim, Jeong-Hwan; Grammatikopoulos, Panagiotis; Diaz, Rosa E. [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Bobo, Jean-François [Centre d’Elaboration de Materiaux et d’Etudes Structurales (CEMES), 29 rue Jeanne Marvig, 31055 Toulouse Cedex 4 (France); Sowwan, Mukhles, E-mail: Mukhles@oist.jp [Nanoparticles by Design Unit, Okinawa Institute of Science and Technology (OIST) Graduate University, 1919-1 Tancha, Onna Son, Okinawa 904-0495 (Japan); Nanotechnology Research Laboratory, Al-Quds University, P.O. Box 51000, East Jerusalem, Palestine (Country Unknown)

2014-11-01

Soft magnetic alloys at the nanoscale level have long generated a vivid interest as candidate materials for technological and biomedical purposes. Consequently, controlling the structure of bimetallic nanoparticles in order to optimize their magnetic properties, such as high magnetization and low coercivity, can significantly boost their potential for related applications. However, traditional synthesis methods stumble upon the long standing challenge of developing true nanoalloys with effective control over morphology and stability against oxidation. Herein, we report on a single-step approach to the gas phase synthesis of soft magnetic bimetallic iron aluminide nanoparticles, using a versatile co-sputter inert gas condensation technique. This method allowed for precise morphological control of the particles; they consisted of an alloy iron aluminide crystalline core (DO{sub 3} phase) and an alumina shell, which reduced inter-particle interactions and also prevented further oxidation and segregation of the bimetallic core. Remarkably, the as-deposited alloy nanoparticles show interesting soft magnetic properties, in that they combine a high saturation magnetization (170 emu/g) and low coercivity (less than 20 Oe) at room temperature. Additional functionality is tenable by modifying the surface of the particles with a polymer, to ensure their good colloidal dispersion in aqueous environments.

Validation of DRAGON side-step method for Bruce-A restart Phase-B physics tests

International Nuclear Information System (INIS)

Shen, W.; Ngo-Trong, C.; Davis, R.S.

2004-01-01

The DRAGON side-step method, developed at AECL, has a number of advantages over the all-DRAGON method that was used before. It is now the qualified method for reactivity-device calculations. Although the side-step-method-generated incremental cross sections have been validated against those previously calculated with the all-DRAGON method, it is highly desirable to validate the side-step method against device-worth measurements in power reactors directly. In this paper, the DRAGON side-step method was validated by comparison with the device-calibration measurements made in Bruce-A NGS Unit 4 restart Phase-B commissioning in 2003. The validation exercise showed excellent results, with the DRAGON code overestimating the measured ZCR worth by ∼5%. A sensitivity study was also performed in this paper to assess the effect of various DRAGON modelling techniques on the incremental cross sections. The assessment shows that the refinement of meshes in 3-D and the use of the side-step method are two major reasons contributing to the improved agreement between the calculated ZCR worths and the measurements. Use of different DRAGON versions, DRAGON libraries, local-parameter core conditions, and weighting techniques for the homogenization of tube clusters inside the ZCR have a very small effect on the ZCR incremental thermal absorption cross section and ZCR reactivity worth. (author)

Two-step versus one-step FT4 assays in heparin treated patients and non-thyroidal illness

International Nuclear Information System (INIS)

Reiners, C.; Bieler, G.; Ertl, G.; Gloss, H.; Boerner, W.

1985-01-01

The primary intention of this study is to inform the clinician about the direction and the order of magnitude of possible disturbances of different FT 4 parameters under the condition mentioned last, which is not uncommon in daily routine. No single FT 4 -RIA proved be valid in severe NTI. There is the risk to misinterprete hyperthyroidism as euthyroidism with 1step assays and the possibility to classify euthyroid patients falsely as hyperthyroid with 2step assays. In relation to this problem, the sometimes lowered FT 4 values by 1step methods are clinically not so important. It has to be established, wether TSH assays of high sensitivity are able to overcome some of the difficulties with determinations of peripheral thyroid hormones in NTI. (orig./MG)

Proposal for a Five-Step Method to Elicit Expert Judgment

Directory of Open Access Journals (Sweden)

Duco Veen

2017-12-01

Full Text Available Elicitation is a commonly used tool to extract viable information from experts. The information that is held by the expert is extracted and a probabilistic representation of this knowledge is constructed. A promising avenue in psychological research is to incorporated experts’ prior knowledge in the statistical analysis. Systematic reviews on elicitation literature however suggest that it might be inappropriate to directly obtain distributional representations from experts. The literature qualifies experts’ performance on estimating elements of a distribution as unsatisfactory, thus reliably specifying the essential elements of the parameters of interest in one elicitation step seems implausible. Providing feedback within the elicitation process can enhance the quality of the elicitation and interactive software can be used to facilitate the feedback. Therefore, we propose to decompose the elicitation procedure into smaller steps with adjustable outcomes. We represent the tacit knowledge of experts as a location parameter and their uncertainty concerning this knowledge by a scale and shape parameter. Using a feedback procedure, experts can accept the representation of their beliefs or adjust their input. We propose a Five-Step Method which consists of (1 Eliciting the location parameter using the trial roulette method. (2 Provide feedback on the location parameter and ask for confirmation or adjustment. (3 Elicit the scale and shape parameter. (4 Provide feedback on the scale and shape parameter and ask for confirmation or adjustment. (5 Use the elicited and calibrated probability distribution in a statistical analysis and update it with data or to compute a prior-data conflict within a Bayesian framework. User feasibility and internal validity for the Five-Step Method are investigated using three elicitation studies.

A two-step method for developing a control rod program for boiling water reactors

International Nuclear Information System (INIS)

Taner, M.S.; Levine, S.H.; Hsiao, M.Y.

1992-01-01

This paper reports on a two-step method that is established for the generation of a long-term control rod program for boiling water reactors (BWRs). The new method assumes a time-variant target power distribution in core depletion. In the new method, the BWR control rod programming is divided into two steps. In step 1, a sequence of optimal, exposure-dependent Haling power distribution profiles is generated, utilizing the spectral shift concept. In step 2, a set of exposure-dependent control rod patterns is developed by using the Haling profiles generated at step 1 as a target. The new method is implemented in a computer program named OCTOPUS. The optimization procedure of OCTOPUS is based on the method of approximation programming, in which the SIMULATE-E code is used to determine the nucleonics characteristics of the reactor core state. In a test in cycle length over a time-invariant, target Haling power distribution case because of a moderate application of spectral shift. No thermal limits of the core were violated. The gain in cycle length could be increased further by broadening the extent of the spetral shift

Validation of a One-Step Method for Extracting Fatty Acids from Salmon, Chicken and Beef Samples.

Science.gov (United States)

Zhang, Zhichao; Richardson, Christine E; Hennebelle, Marie; Taha, Ameer Y

2017-10-01

Fatty acid extraction methods are time-consuming and expensive because they involve multiple steps and copious amounts of extraction solvents. In an effort to streamline the fatty acid extraction process, this study compared the standard Folch lipid extraction method to a one-step method involving a column that selectively elutes the lipid phase. The methods were tested on raw beef, salmon, and chicken. Compared to the standard Folch method, the one-step extraction process generally yielded statistically insignificant differences in chicken and salmon fatty acid concentrations, percent composition and weight percent. Initial testing showed that beef stearic, oleic and total fatty acid concentrations were significantly lower by 9-11% with the one-step method as compared to the Folch method, but retesting on a different batch of samples showed a significant 4-8% increase in several omega-3 and omega-6 fatty acid concentrations with the one-step method relative to the Folch. Overall, the findings reflect the utility of a one-step extraction method for routine and rapid monitoring of fatty acids in chicken and salmon. Inconsistencies in beef concentrations, although minor (within 11%), may be due to matrix effects. A one-step fatty acid extraction method has broad applications for rapidly and routinely monitoring fatty acids in the food supply and formulating controlled dietary interventions. © 2017 Institute of Food Technologists®.

Comparison of Single and Multi-Scale Method for Leaf and Wood Points Classification from Terrestrial Laser Scanning Data

Science.gov (United States)

Wei, Hongqiang; Zhou, Guiyun; Zhou, Junjie

2018-04-01

The classification of leaf and wood points is an essential preprocessing step for extracting inventory measurements and canopy characterization of trees from the terrestrial laser scanning (TLS) data. The geometry-based approach is one of the widely used classification method. In the geometry-based method, it is common practice to extract salient features at one single scale before the features are used for classification. It remains unclear how different scale(s) used affect the classification accuracy and efficiency. To assess the scale effect on the classification accuracy and efficiency, we extracted the single-scale and multi-scale salient features from the point clouds of two oak trees of different sizes and conducted the classification on leaf and wood. Our experimental results show that the balanced accuracy of the multi-scale method is higher than the average balanced accuracy of the single-scale method by about 10 % for both trees. The average speed-up ratio of single scale classifiers over multi-scale classifier for each tree is higher than 30.

Stability analysis and time-step limits for a Monte Carlo Compton-scattering method

International Nuclear Information System (INIS)

Densmore, Jeffery D.; Warsa, James S.; Lowrie, Robert B.

2010-01-01

A Monte Carlo method for simulating Compton scattering in high energy density applications has been presented that models the photon-electron collision kinematics exactly [E. Canfield, W.M. Howard, E.P. Liang, Inverse Comptonization by one-dimensional relativistic electrons, Astrophys. J. 323 (1987) 565]. However, implementing this technique typically requires an explicit evaluation of the material temperature, which can lead to unstable and oscillatory solutions. In this paper, we perform a stability analysis of this Monte Carlo method and develop two time-step limits that avoid undesirable behavior. The first time-step limit prevents instabilities, while the second, more restrictive time-step limit avoids both instabilities and nonphysical oscillations. With a set of numerical examples, we demonstrate the efficacy of these time-step limits.

Method of making stepped photographic density standards of radiographic photographs

International Nuclear Information System (INIS)

Borovin, I.V.; Kondina, M.A.

1987-01-01

In industrial radiography practice the need often arises for a prompt evaluation of the photographic density of an x-ray film. A method of making stepped photographic density standards for industrial radiography by contact printing from a negative is described. The method is intended for industrial radiation flaw detection laboratories not having specialized sensitometric equipment

Synthesis and characterization of copper nanofluid by a novel one-step method

International Nuclear Information System (INIS)

Kumar, S. Ananda; Meenakshi, K. Shree; Narashimhan, B.R.V.; Srikanth, S.; Arthanareeswaran, G.

2009-01-01

This paper presents a novel one-step method for the preparation of stable, non-agglomerated copper nanofluids by reducing copper sulphate pentahydrate with sodium hypophosphite as reducing agent in ethylene glycol as base fluid by means of conventional heating. This is an in situ, one-step method which gives high yield of product with less time consumption. The characterization of the nanofluid is done by particle size analyzer, X-ray diffraction topography, UV-vis analysis and Fourier transform infrared spectroscopy (FT-IR) followed by the study of thermal conductivity of nanofluid by the transient hot wire method

Single-Case Designs and Qualitative Methods: Applying a Mixed Methods Research Perspective

Science.gov (United States)

Hitchcock, John H.; Nastasi, Bonnie K.; Summerville, Meredith

2010-01-01

The purpose of this conceptual paper is to describe a design that mixes single-case (sometimes referred to as single-subject) and qualitative methods, hereafter referred to as a single-case mixed methods design (SCD-MM). Minimal attention has been given to the topic of applying qualitative methods to SCD work in the literature. These two…

Lagrangian fractional step method for the incompressible Navier--Stokes equations on a periodic domain

International Nuclear Information System (INIS)

Boergers, C.; Peskin, C.S.

1987-01-01

In the Lagrangian fractional step method introduced in this paper, the fluid velocity and pressure are defined on a collection of N fluid markers. At each time step, these markers are used to generate a Voronoi diagram, and this diagram is used to construct finite-difference operators corresponding to the divergence, gradient, and Laplacian. The splitting of the Navier--Stokes equations leads to discrete Helmholtz and Poisson problems, which we solve using a two-grid method. The nonlinear convection terms are modeled simply by the displacement of the fluid markers. We have implemented this method on a periodic domain in the plane. We describe an efficient algorithm for the numerical construction of periodic Voronoi diagrams, and we report on numerical results which indicate the the fractional step method is convergent of first order. The overall work per time step is proportional to N log N. copyright 1987 Academic Press, Inc

Accurate step-FMCW ultrasound ranging and comparison with pulse-echo signaling methods

Science.gov (United States)

Natarajan, Shyam; Singh, Rahul S.; Lee, Michael; Cox, Brian P.; Culjat, Martin O.; Grundfest, Warren S.; Lee, Hua

2010-03-01

This paper presents a method setup for high-frequency ultrasound ranging based on stepped frequency-modulated continuous waves (FMCW), potentially capable of producing a higher signal-to-noise ratio (SNR) compared to traditional pulse-echo signaling. In current ultrasound systems, the use of higher frequencies (10-20 MHz) to enhance resolution lowers signal quality due to frequency-dependent attenuation. The proposed ultrasound signaling format, step-FMCW, is well-known in the radar community, and features lower peak power, wider dynamic range, lower noise figure and simpler electronics in comparison to pulse-echo systems. In pulse-echo ultrasound ranging, distances are calculated using the transmit times between a pulse and its subsequent echoes. In step-FMCW ultrasonic ranging, the phase and magnitude differences at stepped frequencies are used to sample the frequency domain. Thus, by taking the inverse Fourier transform, a comprehensive range profile is recovered that has increased immunity to noise over conventional ranging methods. Step-FMCW and pulse-echo waveforms were created using custom-built hardware consisting of an arbitrary waveform generator and dual-channel super heterodyne receiver, providing high SNR and in turn, accuracy in detection.

Novel structure formation at the bottom surface of porous anodic alumina fabricated by single step anodization process.

Science.gov (United States)

Ali, Ghafar; Ahmad, Maqsood; Akhter, Javed Iqbal; Maqbool, Muhammad; Cho, Sung Oh

2010-08-01

A simple approach for the growth of long-range highly ordered nanoporous anodic alumina film in H(2)SO(4) electrolyte through a single step anodization without any additional pre-anodizing procedure is reported. Free-standing porous anodic alumina film of 180 microm thickness with through hole morphology was obtained. A simple and single step process was used for the detachment of alumina from aluminum substrate. The effect of anodizing conditions, such as anodizing voltage and time on the pore diameter and pore ordering is discussed. The metal/oxide and oxide/electrolyte interfaces were examined by high resolution scanning transmission electron microscope. The arrangement of pores on metal/oxide interface was well ordered with smaller diameters than that of the oxide/electrolyte interface. The inter-pore distance was larger in metal/oxide interface as compared to the oxide/electrolyte interface. The size of the ordered domain was found to depend strongly upon anodizing voltage and time. (c) 2010 Elsevier Ltd. All rights reserved.

A two-step method for rapid characterization of electroosmotic flows in capillary electrophoresis.

Science.gov (United States)

Zhang, Wenjing; He, Muyi; Yuan, Tao; Xu, Wei

2017-12-01

The measurement of electroosmotic flow (EOF) is important in a capillary electrophoresis (CE) experiment in terms of performance optimization and stability improvement. Although several methods exist, there are demanding needs to accurately characterize ultra-low electroosmotic flow rates (EOF rates), such as in coated capillaries used in protein separations. In this work, a new method, called the two-step method, was developed to accurately and rapidly measure EOF rates in a capillary, especially for measuring the ultra-low EOF rates in coated capillaries. In this two-step method, the EOF rates were calculated by measuring the migration time difference of a neutral marker in two consecutive experiments, in which a pressure driven was introduced to accelerate the migration and the DC voltage was reversed to switch the EOF direction. Uncoated capillaries were first characterized by both this two-step method and a conventional method to confirm the validity of this new method. Then this new method was applied in the study of coated capillaries. Results show that this new method is not only fast in speed, but also better in accuracy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A simple method for encapsulating single cells in alginate microspheres allows for direct PCR and whole genome amplification.

Directory of Open Access Journals (Sweden)

Saharnaz Bigdeli

Full Text Available Microdroplets are an effective platform for segregating individual cells and amplifying DNA. However, a key challenge is to recover the contents of individual droplets for downstream analysis. This paper offers a method for embedding cells in alginate microspheres and performing multiple serial operations on the isolated cells. Rhodobacter sphaeroides cells were diluted in alginate polymer and sprayed into microdroplets using a fingertip aerosol sprayer. The encapsulated cells were lysed and subjected either to conventional PCR, or whole genome amplification using either multiple displacement amplification (MDA or a two-step PCR protocol. Microscopic examination after PCR showed that the lumen of the occupied microspheres contained fluorescently stained DNA product, but multiple displacement amplification with phi29 produced only a small number of polymerase colonies. The 2-step WGA protocol was successful in generating fluorescent material, and quantitative PCR from DNA extracted from aliquots of microspheres suggested that the copy number inside the microspheres was amplified up to 3 orders of magnitude. Microspheres containing fluorescent material were sorted by a dilution series and screened with a fluorescent plate reader to identify single microspheres. The DNA was extracted from individual isolates, re-amplified with full-length sequencing adapters, and then a single isolate was sequenced using the Illumina MiSeq platform. After filtering the reads, the only sequences that collectively matched a genome in the NCBI nucleotide database belonged to R. sphaeroides. This demonstrated that sequencing-ready DNA could be generated from the contents of a single microsphere without culturing. However, the 2-step WGA strategy showed limitations in terms of low genome coverage and an uneven frequency distribution of reads across the genome. This paper offers a simple method for embedding cells in alginate microspheres and performing PCR on isolated

Kinematic Differences During Single-Leg Step-Down Between Individuals With Femoroacetabular Impingement Syndrome and Individuals Without Hip Pain.

Science.gov (United States)

Lewis, Cara L; Loverro, Kari L; Khuu, Anne

2018-04-01

Study Design Controlled laboratory study, case-control design. Background Despite recognition that femoroacetabular impingement syndrome (FAIS) is a movement-related disorder, few studies have examined dynamic unilateral tasks in individuals with FAIS. Objectives To determine whether movements of the pelvis and lower extremities in individuals with FAIS differ from those in individuals without hip pain during a single-leg step-down, and to analyze kinematic differences between male and female participants within groups. Methods Individuals with FAIS and individuals without hip pain performed a single-leg step-down while kinematic data were collected. Kinematics were evaluated at 60° of knee flexion. A linear regression analysis assessed the main effects of group, sex, and side, and the interaction of sex by group. Results Twenty individuals with FAIS and 40 individuals without hip pain participated. Individuals with FAIS performed the step-down with greater hip flexion (4.9°; 95% confidence interval [CI]: 0.5°, 9.2°) and anterior pelvic tilt (4.1°; 95% CI: 0.9°, 7.3°) than individuals without hip pain. Across groups, female participants performed the task with more hip flexion (6.1°; 95% CI: 1.7°, 10.4°), hip adduction (4.8°; 95% CI: 2.2°, 7.4°), anterior pelvic tilt (5.8°; 95% CI: 2.6°, 9.0°), pelvic drop (1.4°; 95% CI: 0.3°, 2.5°), and thigh adduction (2.7°; 95% CI: 1.3°, 4.2°) than male participants. Conclusion The results of this study suggest that individuals with FAIS have alterations in pelvic motion during a dynamic unilateral task. The noted altered movement patterns in the FAIS group may contribute to the development of hip pain and may be due to impairments that are modifiable through rehabilitation. J Orthop Sports Phys Ther 2018;48(4):270-279. Epub 6 Mar 2018. doi:10.2519/jospt.2018.7794.

Simulation of the two-fluid model on incompressible flow with Fractional Step method for both resolved and unresolved scale interfaces

International Nuclear Information System (INIS)

Hou, Xiaofei; Rigola, Joaquim; Lehmkuhl, Oriol; Oliva, Assensi

2015-01-01

Highlights: • Two phase flow with free surface is solved by means of two-fluid model (TFM). • Fractional Step method and finite volume technique is used to solve TFM. • Conservative Level Set method reduces interface sharpening diffusion problem. • Cases including high density ratios and high viscosities validate the models. - Abstract: In the present paper, the Fractional Step method usually used in single fluid flow is here extended and applied for the two-fluid model resolution using the finite volume discretization. The use of a projection method resolution instead of the usual pressure-correction method for multi-fluid flow, successfully avoids iteration processes. On the other hand, the main weakness of the two fluid model used for simulations of free surface flows, which is the numerical diffusion of the interface, is also solved by means of the conservative Level Set method (interface sharpening) (Strubelj et al., 2009). Moreover, the use of the algorithm proposed has allowed presenting different free-surface cases with or without Level Set implementation even under coarse meshes under a wide range of density ratios. Thus, the numerical results presented, numerically verified, experimentally validated and converged under high density ratios, shows the capability and reliability of this resolution method for both mixed and unmixed flows

A Novel Ship Detection Method Based on Gradient and Integral Feature for Single-Polarization Synthetic Aperture Radar Imagery

Directory of Open Access Journals (Sweden)

Hao Shi

2018-02-01

Full Text Available With the rapid development of remote sensing technologies, SAR satellites like China’s Gaofen-3 satellite have more imaging modes and higher resolution. With the availability of high-resolution SAR images, automatic ship target detection has become an important topic in maritime research. In this paper, a novel ship detection method based on gradient and integral features is proposed. This method is mainly composed of three steps. First, in the preprocessing step, a filter is employed to smooth the clutters and the smoothing effect can be adaptive adjusted according to the statistics information of the sub-window. Thus, it can retain details while achieving noise suppression. Second, in the candidate area extraction, a sea-land segmentation method based on gradient enhancement is presented. The integral image method is employed to accelerate computation. Finally, in the ship target identification step, a feature extraction strategy based on Haar-like gradient information and a Radon transform is proposed. This strategy decreases the number of templates found in traditional Haar-like methods. Experiments were performed using Gaofen-3 single-polarization SAR images, and the results showed that the proposed method has high detection accuracy and rapid computational efficiency. In addition, this method has the potential for on-board processing.

One step linear reconstruction method for continuous wave diffuse optical tomography

Science.gov (United States)

Ukhrowiyah, N.; Yasin, M.

2017-09-01

The method one step linear reconstruction method for continuous wave diffuse optical tomography is proposed and demonstrated for polyvinyl chloride based material and breast phantom. Approximation which used in this method is selecting regulation coefficient and evaluating the difference between two states that corresponding to the data acquired without and with a change in optical properties. This method is used to recovery of optical parameters from measured boundary data of light propagation in the object. The research is demonstrated by simulation and experimental data. Numerical object is used to produce simulation data. Chloride based material and breast phantom sample is used to produce experimental data. Comparisons of results between experiment and simulation data are conducted to validate the proposed method. The results of the reconstruction image which is produced by the one step linear reconstruction method show that the image reconstruction almost same as the original object. This approach provides a means of imaging that is sensitive to changes in optical properties, which may be particularly useful for functional imaging used continuous wave diffuse optical tomography of early diagnosis of breast cancer.

Methods for growth of relatively large step-free SiC crystal surfaces

Science.gov (United States)

Neudeck, Philip G. (Inventor); Powell, J. Anthony (Inventor)

2002-01-01

A method for growing arrays of large-area device-size films of step-free (i.e., atomically flat) SiC surfaces for semiconductor electronic device applications is disclosed. This method utilizes a lateral growth process that better overcomes the effect of extended defects in the seed crystal substrate that limited the obtainable step-free area achievable by prior art processes. The step-free SiC surface is particularly suited for the heteroepitaxial growth of 3C (cubic) SiC, AlN, and GaN films used for the fabrication of both surface-sensitive devices (i.e., surface channel field effect transistors such as HEMT's and MOSFET's) as well as high-electric field devices (pn diodes and other solid-state power switching devices) that are sensitive to extended crystal defects.

Comparison of Stepped Care Delivery Against a Single, Empirically Validated Cognitive-Behavioral Therapy Program for Youth With Anxiety: A Randomized Clinical Trial.

Science.gov (United States)

Rapee, Ronald M; Lyneham, Heidi J; Wuthrich, Viviana; Chatterton, Mary Lou; Hudson, Jennifer L; Kangas, Maria; Mihalopoulos, Cathrine

2017-10-01

Stepped care is embraced as an ideal model of service delivery but is minimally evaluated. The aim of this study was to evaluate the efficacy of cognitive-behavioral therapy (CBT) for child anxiety delivered via a stepped-care framework compared against a single, empirically validated program. A total of 281 youth with anxiety disorders (6-17 years of age) were randomly allocated to receive either empirically validated treatment or stepped care involving the following: (1) low intensity; (2) standard CBT; and (3) individually tailored treatment. Therapist qualifications increased at each step. Interventions did not differ significantly on any outcome measures. Total therapist time per child was significantly shorter to deliver stepped care (774 minutes) compared with best practice (897 minutes). Within stepped care, the first 2 steps returned the strongest treatment gains. Stepped care and a single empirically validated program for youth with anxiety produced similar efficacy, but stepped care required slightly less therapist time. Restricting stepped care to only steps 1 and 2 would have led to considerable time saving with modest loss in efficacy. Clinical trial registration information-A Randomised Controlled Trial of Standard Care Versus Stepped Care for Children and Adolescents With Anxiety Disorders; http://anzctr.org.au/; ACTRN12612000351819. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Design and fabrication of a chitosan hydrogel with gradient structures via a step-by-step cross-linking process.

Science.gov (United States)

Xu, Yongxiang; Yuan, Shenpo; Han, Jianmin; Lin, Hong; Zhang, Xuehui

2017-11-15

The development of scaffolds to mimic the gradient structure of natural tissue is an important consideration for effective tissue engineering. In the present study, a physical cross-linking chitosan hydrogel with gradient structures was fabricated via a step-by-step cross-linking process using sodium tripolyphosphate and sodium hydroxide as sequential cross-linkers. Chitosan hydrogels with different structures (single, double, and triple layers) were prepared by modifying the gelling process. The properties of the hydrogels were further adjusted by varying the gelling conditions, such as gelling time, pH, and composition of the crosslinking solution. Slight cytotoxicity was showed in MTT assay for hydrogels with uncross-linking chitosan solution and non-cytotoxicity was showed for other hydrogels. The results suggest that step-by-step cross-linking represents a practicable method to fabricate scaffolds with gradient structures. Copyright © 2017. Published by Elsevier Ltd.

Aerial robot intelligent control method based on back-stepping

Science.gov (United States)

Zhou, Jian; Xue, Qian

2018-05-01

The aerial robot is characterized as strong nonlinearity, high coupling and parameter uncertainty, a self-adaptive back-stepping control method based on neural network is proposed in this paper. The uncertain part of the aerial robot model is compensated online by the neural network of Cerebellum Model Articulation Controller and robust control items are designed to overcome the uncertainty error of the system during online learning. At the same time, particle swarm algorithm is used to optimize and fix parameters so as to improve the dynamic performance, and control law is obtained by the recursion of back-stepping regression. Simulation results show that the designed control law has desired attitude tracking performance and good robustness in case of uncertainties and large errors in the model parameters.

Single step synthesis and organization of gold colloids assisted by copolymer templates

Science.gov (United States)

Sarrazin, Aurélien; Gontier, Arthur; Plaud, Alexandre; Béal, Jérémie; Yockell-Lelièvre, Hélène; Bijeon, Jean-Louis; Plain, Jérôme; Adam, Pierre-Michel; Maurer, Thomas

2014-06-01

We report here an original single-step process for the synthesis and self-organization of gold colloids by simply incorporating gold salts into a solution prepared using polystyrene (PS)-polymethylmethacrylate copolymer and thiolated PS with propylene glycol methyl ether acetate as a solvent. The spin-coating and annealing of this solution then allows the formation of PS domains. Depending on the polymer concentration of the as-prepared solution, there can be either one or several gold nanoparticles (Au NPs) per PS domain. For high concentrations of Au NPs in PS domains, the coupling between plasmonic NPs leads to the observation of a second peak in the optical extinction spectrum. Such a collective effect could be relevant for the development of optical strain sensors in the near future.

A new plastic scintillation resin for single-step separation, concentration and measurement of technetium-99.

Science.gov (United States)

Barrera, J; Tarancón, A; Bagán, H; García, J F

2016-09-14

Technetium is a synthetic element with no stable isotopes, produced as waste in nuclear power plants and in cyclotrons used for nuclear medicine. The element has high mobility, in the form of TcO4(-); its determination is therefore important for environmental protection. Technetium is found in low concentrations and therefore common methods for its analysis include long treatments in several steps and require large amounts of reagents for its purification and preconcentration. Plastic scintillation resins (PSresin) are novel materials used to separate, preconcentrate and measure radionuclides in a single step. The objective of this study is to prepare and characterise a PSresin for the preconcentration and measurement of (99)Tc. The study first evaluates the reproducibility of the production of PSresins between batches and over time; showing good reproducibility and storage stability. Next, we studied the effect of some common non-radioactive interferences, showing small influences on measurement, and radioactive interferences ((36)Cl and (238)U/(234)U). (36)Cl can be removed by a simple treatment with 0.5 M HCl and (238)U/(234)U can be removed from the column by cleaning with a mixture of 0.1 M HNO3 and 0.1 M HF. In the latter case, a slight change in the morphology of the PSresin caused an increase in detection efficiency. Finally, the PSresin was applied to the measurement of real spiked samples (sea water and urine) with deviations lower than 10% in all cases. Copyright © 2016 Elsevier B.V. All rights reserved.

A one-step method to fabricate PLLA scaffolds with deposition of bioactive hydroxyapatite and collagen using ice-based microporogens

Science.gov (United States)

Li, Jiashen; Chen, Yun; Mak, Arthur F.T.; Tuan, Rocky S.; Li, Lin; Li, Yi

2010-01-01

Porous poly(L-lactic acid) (PLLA) scaffolds with bioactive coatings were prepared by a novel one-step method. In this process, ice-based microporogens containing bioactive molecules, such as hydroxyapatite (HA) and collagen, served as both porogens to form the porous structure and vehicles to transfer the bioactive molecules to the inside of PLLA scaffolds in a single step. Based on scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis, the bioactive components were found to be transferred successfully from the porogens to PLLA scaffolds evenly. Osteoblast cells were used to evaluate the cellular behaviors of the composite scaffolds. After 8 days culturing, MTT assay and alkaline phosphatase (ALP) activity results suggested that HA/collagen could improve the interactions between osteoblast cells and the polymeric scaffold. PMID:20004261

Single-step brazing process for mono-block joints and mechanical testing

Energy Technology Data Exchange (ETDEWEB)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S. [Politecnico di Torino, Materials Science and Chemical Engineering Dept., Torino (Italy); Merola, M. [ITER International Team, llER Joint Work Site, Cadarache, 13 - St Paul Lez Durance (France)

2007-07-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non

Single-step brazing process for mono-block joints and mechanical testing

International Nuclear Information System (INIS)

Casalegno, V.; Ferraris, M.; Salvo, M.; Rizzo, S.; Merola, M.

2007-01-01

Full text of publication follows: Plasma facing components act as actively cooled thermal shields to sustain thermal and particle loads during normal and transient operations in ITER (International Thermonuclear Experimental Reactor). The plasma-facing layer is referred to as 'armour', which is made of either carbon fibre reinforced carbon composite (CFC) or tungsten (W). CFC is the reference design solution for the lower part of the vertical target of the ITER divertor. The armour is joined onto an actively cooled substrate, the heat sink, made of precipitation hardened copper alloy CuCrZr through a thin pure copper interlayer to decrease, by plastic deformation, the joint interface stresses; in fact, the CFC to Cu joint is affected by the CTE mismatch between the ceramic and metallic material. A new method of joining CFC to copper and CFC/Cu to CuCrZr alloy was effectively developed for the flat-type configuration; the feasibility of this process also for mono-block geometry and the development of a procedure for testing mono-block-type mock-ups is described in this work. The mono-block configuration consists of copper alloy pipe shielded by CFC blocks. It is worth noting that in mono-block configuration, the large thermal expansion mismatch between CFC and copper alloy is more significant than for flat-tile configuration, due to curved interfaces. The joining technique foresees a single-step brazing process: the brazing of the three materials (CFC-Cu-CuCrZr) can be performed in a single heat treatment using the same Cu/Ge based braze. The composite surface was modified by solid state reaction with chromium with the purpose of increasing the wettability of CFC by the brazing alloy. The CFC substrate reacts with Cr which, forming a carbide layer, allows a large reduction of the contact angle; then, the brazing of CFC to pure copper and pure copper to CuCrZr by the same treatment is feasible. This process allows to obtain good joints using a non-active brazing

Single-Step Transepithelial PRK vs Alcohol-Assisted PRK in Myopia and Compound Myopic Astigmatism Correction

OpenAIRE

Kaluzny, Bartlomiej J.; Cieslinska, Iwona; Mosquera, Samuel A.; Verma, Shwetabh

2016-01-01

Abstract Transepithelial photorefractive keratectomy (tPRK), where both the epithelium and stroma are removed in a single-step, is a relatively new procedure of laser refractive error correction. This study compares the 3-month results of myopia and compound myopic astigmatism correction by tPRK or conventional alcohol-assisted PRK (aaPRK). This prospective, nonrandomized, case?control study recruited 148 consecutive patients; 93 underwent tPRK (173 eyes) and 55 aaPRK (103 eyes). Refractive r...

Dose Rate Experiment at JET for Benchmarking the Calculation Direct One Step Method

International Nuclear Information System (INIS)

Angelone, M.; Petrizzi, L.; Pillon, M.; Villari, R.; Popovichev, S.

2006-01-01

Neutrons produced by D-D and D-T plasmas induce the activation of tokamak materials and of components. The development of reliable methods to assess dose rates is a key issue for maintenance and operating nuclear machines, in normal and off-normal conditions. In the frame of the EFDA Fusion Technology work programme, a computational tool based upon MCNP Monte Carlo code has been developed to predict the dose rate after shutdown: it is called Direct One Step Method (D1S). The D1S is an innovative approach in which the decay gammas are coupled to the neutrons as in the prompt case and they are transported in one single step in the same run. Benchmarking of this new tool with experimental data taken in a complex geometry like that of a tokamak is a fundamental step to test the reliability of the D1S method. A dedicated benchmark experiment was proposed for the 2005-2006 experimental campaign of JET. Two irradiation positions have been selected for the benchmark: one inner position inside the vessel, not far from the plasma, called the 2 upper irradiation end (IE2), where neutron fluence is relatively high. The second position is just outside a vertical port in an external position (EX). Here the neutron flux is lower and the dose rate to be measured is not very far from the residual background. Passive detectors are used for in-vessel measurements: the high sensitivity Thermo Luminescent Dosimeters (TLDs) GR-200A (natural LiF), which ensure measurements down to environmental dose level. An active detector of Geiger-Muller (GM) type is used for out of vessel dose rate measurement. Before their use the detectors were calibrated in a secondary gamma-ray standard (Cs-137 and Co-60) facility in term of air-kerma. The background measurement was carried-out in the period July -September 2005 in the outside position EX using the GM tube and in September 2005 inside the vacuum vessel using TLD detectors located in the 2 Upper irradiation end IE2. In the present work

Colloidal Quantum Dot Inks for Single-Step-Fabricated Field-Effect Transistors: The Importance of Postdeposition Ligand Removal.

Science.gov (United States)

Balazs, Daniel M; Rizkia, Nisrina; Fang, Hong-Hua; Dirin, Dmitry N; Momand, Jamo; Kooi, Bart J; Kovalenko, Maksym V; Loi, Maria Antonietta

2018-02-14

Colloidal quantum dots are a class of solution-processed semiconductors with good prospects for photovoltaic and optoelectronic applications. Removal of the surfactant, so-called ligand exchange, is a crucial step in making the solid films conductive, but performing it in solid state introduces surface defects and cracks in the films. Hence, the formation of thick, device-grade films have only been possible through layer-by-layer processing, limiting the technological interest for quantum dot solids. Solution-phase ligand exchange before the deposition allows for the direct deposition of thick, homogeneous films suitable for device applications. In this work, fabrication of field-effect transistors in a single step is reported using blade-coating, an upscalable, industrially relevant technique. Most importantly, a postdeposition washing step results in device properties comparable to the best layer-by-layer processed devices, opening the way for large-scale fabrication and further interest from the research community.

Fluoroscopic-guided primary single-step percutaneous gastrostomy. Initial results using the Freka {sup registered} GastroTube; Primaere einzeitige durchleuchtungsgesteuerte perkutane Gastrostomie (PG). Erste Ergebnisse mit dem Freka {sup registered} GastroTube

Energy Technology Data Exchange (ETDEWEB)

Hahne, J.D.; Schoennagel, B.P.; Arndt, C.; Bannas, P.; Koops, A.; Adam, G.; Habermann, C.R. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Zentrum fuer Radiologie; Herrmann, J. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Zentrum fuer Radiologie; Universitaetsklinikum Hamburg-Eppendorf (Germany). Abt. Paediatrische Radiologie

2011-07-15

Purpose: To determine the practicability and outcome of fluoroscopic-guided primary one-step treatment of percutaneous gastrostomy (PG) with the system Freka {sup registered} Gastro Tube (Fresenius Kabi, Germany). Materials and Methods: In 39 patients (mean age 62.7 {+-} 12.0 years), primary PG was performed based on clinical indication from August 2009 to April 2010. The intervention was performed by an experienced radiologist under aseptic conditions by direct puncture with Freka {sup registered} Gastro Tube under fluoroscopic guidance. The clinical data and outcome as well as any complications originated from the electronic archive of the University Medical Center Hamburg-Eppendorf. Results: The intervention was technically successful in all 39 patients. Within the mean follow-up time of 155.3 {+-} 73.6 days, 29 patients (74.4 %) did not experience complications. 10 patients (25.6 %) had to be revised. Complications manifested after a mean of 135.6 {+-} 61.2 days and mainly corresponded to accidental dislocation (50 %). One patient had to be surgically revised under suspicion of a malpositioned tube and suspected intestinal perforation. Clinically relevant wound infections were not detected. The total costs per patient were 553.17 Euro for our single-step treatment (OPS 5 - 431.x) vs. 963.69 Euro (OPS 5 - 431.x and OPS 8 - 123.0) for the recommended two-step treatment. Conclusion: Fluoroscopic-guided primary single-step treatment with Freka {sup registered} Gastro Tube system is feasible and not associated with an increased complication rate when compared to published literature applying a two-step treatment approach. Material costs as well as human and time resources could be significantly reduced using the single-step treatment. (orig.)

SPAR-H Step-by-Step Guidance

Energy Technology Data Exchange (ETDEWEB)

April M. Whaley; Dana L. Kelly; Ronald L. Boring; William J. Galyean

2012-06-01

Step-by-step guidance was developed recently at Idaho National Laboratory for the US Nuclear Regulatory Commission on the use of the Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) method for quantifying Human Failure Events (HFEs). This work was done to address SPAR-H user needs, specifically requests for additional guidance on the proper application of various aspects of the methodology. This paper overviews the steps of the SPAR-H analysis process and highlights some of the most important insights gained during the development of the step-by-step directions. This supplemental guidance for analysts is applicable when plant-specific information is available, and goes beyond the general guidance provided in existing SPAR-H documentation. The steps highlighted in this paper are: Step-1, Categorizing the HFE as Diagnosis and/or Action; Step-2, Rate the Performance Shaping Factors; Step-3, Calculate PSF-Modified HEP; Step-4, Accounting for Dependence, and; Step-5, Minimum Value Cutoff.

Two-step method for creating a gastric tube during laparoscopic-thoracoscopic Ivor-Lewis esophagectomy.

Science.gov (United States)

Liu, Yu; Li, Ji-Jia; Zu, Peng; Liu, Hong-Xu; Yu, Zhan-Wu; Ren, Yi

2017-12-07

To introduce a two-step method for creating a gastric tube during laparoscopic-thoracoscopic Ivor-Lewis esophagectomy and assess its clinical application. One hundred and twenty-two patients with middle or lower esophageal cancer who underwent laparoscopic-thoracoscopic Ivor-Lewis esophagectomy at Liaoning Cancer Hospital and Institute from March 2014 to March 2016 were included in this study, and divided into two groups based on the procedure used for creating a gastric tube. One group used a two-step method for creating a gastric tube, and the other group used the conventional method. The two groups were compared regarding the operating time, surgical complications, and number of stapler cartridges used. The mean operating time was significantly shorter in the two-step method group than in the conventional method group [238 (179-293) min vs 272 (189-347) min, P creating a gastric tube during laparoscopic-thoracoscopic Ivor-Lewis esophagectomy has the advantages of simple operation, minimal damage to the tubular stomach, and reduced use of stapler cartridges.

A Three Step Explicit Method for Direct Solution of Third Order ...

African Journals Online (AJOL)

This study produces a three step discrete Linear Multistep Method for Direct solution of third order initial value problems of ordinary differential equations of the form y'''= f(x,y,y',y''). Taylor series expansion technique was adopted in the development of the method. The differential system from the basis polynomial function to ...

An efficient single-step scheme for manipulating quantum information of two trapped ions beyond the Lamb-Dicke limit

International Nuclear Information System (INIS)

Wei, L.F.; Nori, Franco

2003-01-01

Based on the exact conditional quantum dynamics for a two-ion system, we propose an efficient single-step scheme for coherently manipulating quantum information of two trapped cold ions by using a pair of synchronous laser pulses. Neither the auxiliary atomic level nor the Lamb-Dicke approximation are needed

The effects of strength and power training on single-step balance recovery in older adults: a preliminary study.

Science.gov (United States)

Pamukoff, Derek N; Haakonssen, Eric C; Zaccaria, Joseph A; Madigan, Michael L; Miller, Michael E; Marsh, Anthony P

2014-01-01

Improving muscle strength and power may mitigate the effects of sarcopenia, but it is unknown if this improves an older adult's ability to recover from a large postural perturbation. Forward tripping is prevalent in older adults and lateral falls are important due to risk of hip fracture. We used a forward and a lateral single-step balance recovery task to examine the effects of strength training (ST) or power (PT) training on single-step balance recovery in older adults. Twenty older adults (70.8±4.4 years, eleven male) were randomly assigned to either a 6-week (three times/week) lower extremity ST or PT intervention. Maximum forward (FLean(max)) and lateral (LLean(max)) lean angle and strength and power in knee extension and leg press were assessed at baseline and follow-up. Fifteen participants completed the study (ST =7, PT =8). Least squares means (95% CI) for ΔFLean(max) (ST: +4.1° [0.7, 7.5]; PT: +0.6° [-2.5, 3.8]) and ΔLLean(max) (ST: +2.2° [0.4, 4.1]; PT: +2.6° [0.9, 4.4]) indicated no differences between groups following training. In exploratory post hoc analyses collapsed by group, ΔFLean(max) was +2.4° (0.1, 4.7) and ΔLLean(max) was +2.4° (1.2, 3.6). These improvements on the balance recovery tasks ranged from ~15%-30%. The results of this preliminary study suggest that resistance training may improve balance recovery performance, and that, in this small sample, PT did not lead to larger improvements in single-step balance recovery compared to ST.

Two-step calibration method for multi-algorithm score-based face recognition systems by minimizing discrimination loss

NARCIS (Netherlands)

Susyanto, N.; Veldhuis, R.N.J.; Spreeuwers, L.J.; Klaassen, C.A.J.; Fierrez, J.; Li, S.Z.; Ross, A.; Veldhuis, R.; Alonso-Fernandez, F.; Bigun, J.

2016-01-01

We propose a new method for combining multi-algorithm score-based face recognition systems, which we call the two-step calibration method. Typically, algorithms for face recognition systems produce dependent scores. The two-step method is based on parametric copulas to handle this dependence. Its

Stability of cell-free DNA from maternal plasma isolated following a single centrifugation step.

Science.gov (United States)

Barrett, Angela N; Thadani, Henna A; Laureano-Asibal, Cecille; Ponnusamy, Sukumar; Choolani, Mahesh

2014-12-01

Cell-free fetal DNA can be used for prenatal testing with no procedure-related risk to the fetus. However, yield of fetal DNA is low compared with maternal cell-free DNA fragments, resulting in technical challenges for some downstream applications. To maximize the fetal fraction, careful blood processing procedures are essential. We demonstrate that fetal fraction can be preserved using a single centrifugation step followed by postage of plasma to the laboratory for further processing. Digital PCR was used to quantify copies of total, maternal, and fetal DNA present in single-spun plasma at time points over a two-week period, compared with immediately processed double-spun plasma, with storage at room temperature, 4°C, and -80°C representing different postage scenarios. There was no significant change in total, maternal, or fetal DNA copy numbers when single-spun plasma samples were stored for up to 1 week at room temperature and 2 weeks at -80°C compared with plasma processed within 4 h. Following storage at 4°C no change in composition of cell-free DNA was observed. Single-spun plasma can be transported at room temperature if the journey is expected to take one week or less; shipping on dry ice is preferable for longer journeys. © 2014 John Wiley & Sons, Ltd.

Design of a Two-Step Calibration Method of Kinematic Parameters for Serial Robots

Science.gov (United States)

WANG, Wei; WANG, Lei; YUN, Chao

2017-03-01

Serial robots are used to handle workpieces with large dimensions, and calibrating kinematic parameters is one of the most efficient ways to upgrade their accuracy. Many models are set up to investigate how many kinematic parameters can be identified to meet the minimal principle, but the base frame and the kinematic parameter are indistinctly calibrated in a one-step way. A two-step method of calibrating kinematic parameters is proposed to improve the accuracy of the robot's base frame and kinematic parameters. The forward kinematics described with respect to the measuring coordinate frame are established based on the product-of-exponential (POE) formula. In the first step the robot's base coordinate frame is calibrated by the unit quaternion form. The errors of both the robot's reference configuration and the base coordinate frame's pose are equivalently transformed to the zero-position errors of the robot's joints. The simplified model of the robot's positioning error is established in second-power explicit expressions. Then the identification model is finished by the least square method, requiring measuring position coordinates only. The complete subtasks of calibrating the robot's 39 kinematic parameters are finished in the second step. It's proved by a group of calibration experiments that by the proposed two-step calibration method the average absolute accuracy of industrial robots is updated to 0.23 mm. This paper presents that the robot's base frame should be calibrated before its kinematic parameters in order to upgrade its absolute positioning accuracy.

Step size of the rotary proton motor in single FoF1-ATP synthase from a thermoalkaliphilic bacterium by DCO-ALEX FRET

Science.gov (United States)

Hammann, Eva; Zappe, Andrea; Keis, Stefanie; Ernst, Stefan; Matthies, Doreen; Meier, Thomas; Cook, Gregory M.; Börsch, Michael

2012-02-01

Thermophilic enzymes operate at high temperatures but show reduced activities at room temperature. They are in general more stable during preparation and, accordingly, are considered to be more rigid in structure. Crystallization is often easier compared to proteins from bacteria growing at ambient temperatures, especially for membrane proteins. The ATP-producing enzyme FoF1-ATP synthase from thermoalkaliphilic Caldalkalibacillus thermarum strain TA2.A1 is driven by a Fo motor consisting of a ring of 13 c-subunits. We applied a single-molecule Förster resonance energy transfer (FRET) approach using duty cycle-optimized alternating laser excitation (DCO-ALEX) to monitor the expected 13-stepped rotary Fo motor at work. New FRET transition histograms were developed to identify the smaller step sizes compared to the 10-stepped Fo motor of the Escherichia coli enzyme. Dwell time analysis revealed the temperature and the LDAO dependence of the Fo motor activity on the single molecule level. Back-and-forth stepping of the Fo motor occurs fast indicating a high flexibility in the membrane part of this thermophilic enzyme.

The large discretization step method for time-dependent partial differential equations

Science.gov (United States)

Haras, Zigo; Taasan, Shlomo

1995-01-01

A new method for the acceleration of linear and nonlinear time dependent calculations is presented. It is based on the Large Discretization Step (LDS) approximation, defined in this work, which employs an extended system of low accuracy schemes to approximate a high accuracy discrete approximation to a time dependent differential operator. Error bounds on such approximations are derived. These approximations are efficiently implemented in the LDS methods for linear and nonlinear hyperbolic equations, presented here. In these algorithms the high and low accuracy schemes are interpreted as the same discretization of a time dependent operator on fine and coarse grids, respectively. Thus, a system of correction terms and corresponding equations are derived and solved on the coarse grid to yield the fine grid accuracy. These terms are initialized by visiting the fine grid once in many coarse grid time steps. The resulting methods are very general, simple to implement and may be used to accelerate many existing time marching schemes.

Effect of annealing temperature on a single step processed Cu{sub 2}ZnSnS{sub 4} thin film via solution method

Energy Technology Data Exchange (ETDEWEB)

Prabeesh, P.; Selvam, I. Packia; Potty, S.N.

2016-05-01

Cu{sub 2}ZnSnS{sub 4} (CZTS) is a promising material for thin film solar cell applications because of its excellent photovoltaic properties, high abundance and non-toxicity. Thin films of CZTS are generally fabricated by vacuum based techniques or by using toxic solvents and these routes reduce its attention as a low cost and environmental friendly material. In this study, we have prepared CZTS through a solution based single step approach using non-toxic chemicals by spin coating and studied the effect of annealing temperature in the range 350–550 °C in nitrogen atmosphere on structural, optical and electrical properties. XRD results revealed the formation of kesterite phase at all annealing temperatures, while the Raman studies indicated Cu{sub 2}SnS{sub 2} impurity phase in the film annealed at 550 °C. Band gap of the films annealed in nitrogen varies from 1.46 eV to 1.56 eV, depending on the annealing temperature. Optimum properties, such as, good crystallinity, dense structure, ideal band gap (1.49 eV) and good absorption coefficient (10{sup 4} cm{sup −1}), were obtained for the film annealed at 500 °C for 30 min in nitrogen. - Highlights: • Prepared CZTS film through one-step liquid based approach using non-toxic chemicals. • Studied the effect of N{sub 2} annealing on structural, optical and electrical properties. • The phase pure CZTS absorber film exhibited excellent photovoltaic properties • The film annealed at 500 °C for 30 min in nitrogen exhibited optimum properties.

A new plastic scintillation resin for single-step separation, concentration and measurement of technetium-99

Energy Technology Data Exchange (ETDEWEB)

Barrera, J. [Department of Analytical Chemistry, Universitat de Barcelona, Martí i Franqués, 1-11, E-08028, Barcelona (Spain); Tarancón, A., E-mail: alex.tarancon@ub.edu [Department of Analytical Chemistry, Universitat de Barcelona, Martí i Franqués, 1-11, E-08028, Barcelona (Spain); Bagán, H. [Department of Pure and Applied Biochemistry, Lund University, Getingevägen 60, hus II, 22100 SE, Lund (Sweden); García, J.F. [Department of Analytical Chemistry, Universitat de Barcelona, Martí i Franqués, 1-11, E-08028, Barcelona (Spain)

2016-09-14

Technetium is a synthetic element with no stable isotopes, produced as waste in nuclear power plants and in cyclotrons used for nuclear medicine. The element has high mobility, in the form of TcO{sub 4}{sup −}; its determination is therefore important for environmental protection. Technetium is found in low concentrations and therefore common methods for its analysis include long treatments in several steps and require large amounts of reagents for its purification and preconcentration. Plastic scintillation resins (PSresin) are novel materials used to separate, preconcentrate and measure radionuclides in a single step. The objective of this study is to prepare and characterise a PSresin for the preconcentration and measurement of {sup 99}Tc. The study first evaluates the reproducibility of the production of PSresins between batches and over time; showing good reproducibility and storage stability. Next, we studied the effect of some common non-radioactive interferences, showing small influences on measurement, and radioactive interferences ({sup 36}Cl and {sup 238}U/{sup 234}U). {sup 36}Cl can be removed by a simple treatment with 0.5 M HCl and {sup 238}U/{sup 234}U can be removed from the column by cleaning with a mixture of 0.1 M HNO{sub 3} and 0.1 M HF. In the latter case, a slight change in the morphology of the PSresin caused an increase in detection efficiency. Finally, the PSresin was applied to the measurement of real spiked samples (sea water and urine) with deviations lower than 10% in all cases. - Highlights: • A plastic scintillation resin for selective analysis of {sup 99}Tc has been developed. • The method is valid for analysis of {sup 99}Tc in seawater and urine samples. • Presence of Cl{sup −}, NO{sub 3}{sup −}, SO{sub 4}{sup 2−}, {sup 36}Cl, U and Th not affect retention of {sup 99}Tc.

A new plastic scintillation resin for single-step separation, concentration and measurement of technetium-99

International Nuclear Information System (INIS)

Barrera, J.; Tarancón, A.; Bagán, H.; García, J.F.

2016-01-01

Technetium is a synthetic element with no stable isotopes, produced as waste in nuclear power plants and in cyclotrons used for nuclear medicine. The element has high mobility, in the form of TcO_4"−; its determination is therefore important for environmental protection. Technetium is found in low concentrations and therefore common methods for its analysis include long treatments in several steps and require large amounts of reagents for its purification and preconcentration. Plastic scintillation resins (PSresin) are novel materials used to separate, preconcentrate and measure radionuclides in a single step. The objective of this study is to prepare and characterise a PSresin for the preconcentration and measurement of "9"9Tc. The study first evaluates the reproducibility of the production of PSresins between batches and over time; showing good reproducibility and storage stability. Next, we studied the effect of some common non-radioactive interferences, showing small influences on measurement, and radioactive interferences ("3"6Cl and "2"3"8U/"2"3"4U). "3"6Cl can be removed by a simple treatment with 0.5 M HCl and "2"3"8U/"2"3"4U can be removed from the column by cleaning with a mixture of 0.1 M HNO_3 and 0.1 M HF. In the latter case, a slight change in the morphology of the PSresin caused an increase in detection efficiency. Finally, the PSresin was applied to the measurement of real spiked samples (sea water and urine) with deviations lower than 10% in all cases. - Highlights: • A plastic scintillation resin for selective analysis of "9"9Tc has been developed. • The method is valid for analysis of "9"9Tc in seawater and urine samples. • Presence of Cl"−, NO_3"−, SO_4"2"−, "3"6Cl, U and Th not affect retention of "9"9Tc.

Single step synthesis and organization of gold colloids assisted by copolymer templates

International Nuclear Information System (INIS)

Sarrazin, Aurélien; Gontier, Arthur; Plaud, Alexandre; Béal, Jérémie; Yockell-Lelièvre, Hélène; Bijeon, Jean-Louis; Plain, Jérôme; Adam, Pierre-Michel; Maurer, Thomas

2014-01-01

We report here an original single-step process for the synthesis and self-organization of gold colloids by simply incorporating gold salts into a solution prepared using polystyrene (PS)-polymethylmethacrylate copolymer and thiolated PS with propylene glycol methyl ether acetate as a solvent. The spin-coating and annealing of this solution then allows the formation of PS domains. Depending on the polymer concentration of the as-prepared solution, there can be either one or several gold nanoparticles (Au NPs) per PS domain. For high concentrations of Au NPs in PS domains, the coupling between plasmonic NPs leads to the observation of a second peak in the optical extinction spectrum. Such a collective effect could be relevant for the development of optical strain sensors in the near future. (papers)

Ion-step method for surface potential sensing of silicon nanowires

NARCIS (Netherlands)

Chen, S.; van Nieuwkasteele, Jan William; van den Berg, Albert; Eijkel, Jan C.T.

2016-01-01

This paper presents a novel stimulus-response method for surface potential sensing of silicon nanowire (Si NW) field-effect transistors. When an "ion-step" from low to high ionic strength is given as a stimulus to the gate oxide surface, an increase of double layer capacitance is therefore expected.

Single-step generation of fluorophore-encapsulated gold nanoparticle core-shell materials

International Nuclear Information System (INIS)

Sardar, R; Shem, P M; Pecchia-Bekkum, C; Bjorge, N S; Shumaker-Parry, J S

2010-01-01

We report a simple route to produce fluorophore-encapsulated gold nanoparticles (AuNPs) in a single step under aqueous conditions using the fluorophore 1-pyrenemethylamine (PMA). Different amounts of PMA were used and the resulting core-shell gold nanoparticles were analyzed using UV-visible absorption spectroscopy, fluorescence spectroscopy, and transmission and scanning electron microscopy. Electron microscopy analysis shows nanoparticles consisting of a gold nanoparticle core which is encapsulated with a lower contrast shell. In the UV-visible spectra, we observed a significant red shift (37 nm) of the localized surface plasmon resonance (LSPR) absorption maximum (λ max ) compared to citrate-stabilized AuNPs of a similar size. We attribute the prominent LSPR wavelength shift for PMA-AuNP conjugates to the increase in the local dielectric environment near the gold nanoparticles due to the shell formation. This simple, aqueous-based synthesis is a new approach to the production of fluorophore-encapsulated AuNPs that could be applicable in biological sensing systems and photonic device fabrication.

A Dimensionality Reduction-Based Multi-Step Clustering Method for Robust Vessel Trajectory Analysis

Directory of Open Access Journals (Sweden)

Huanhuan Li

2017-08-01

Full Text Available The Shipboard Automatic Identification System (AIS is crucial for navigation safety and maritime surveillance, data mining and pattern analysis of AIS information have attracted considerable attention in terms of both basic research and practical applications. Clustering of spatio-temporal AIS trajectories can be used to identify abnormal patterns and mine customary route data for transportation safety. Thus, the capacities of navigation safety and maritime traffic monitoring could be enhanced correspondingly. However, trajectory clustering is often sensitive to undesirable outliers and is essentially more complex compared with traditional point clustering. To overcome this limitation, a multi-step trajectory clustering method is proposed in this paper for robust AIS trajectory clustering. In particular, the Dynamic Time Warping (DTW, a similarity measurement method, is introduced in the first step to measure the distances between different trajectories. The calculated distances, inversely proportional to the similarities, constitute a distance matrix in the second step. Furthermore, as a widely-used dimensional reduction method, Principal Component Analysis (PCA is exploited to decompose the obtained distance matrix. In particular, the top k principal components with above 95% accumulative contribution rate are extracted by PCA, and the number of the centers k is chosen. The k centers are found by the improved center automatically selection algorithm. In the last step, the improved center clustering algorithm with k clusters is implemented on the distance matrix to achieve the final AIS trajectory clustering results. In order to improve the accuracy of the proposed multi-step clustering algorithm, an automatic algorithm for choosing the k clusters is developed according to the similarity distance. Numerous experiments on realistic AIS trajectory datasets in the bridge area waterway and Mississippi River have been implemented to compare our

A Dimensionality Reduction-Based Multi-Step Clustering Method for Robust Vessel Trajectory Analysis.

Science.gov (United States)

Li, Huanhuan; Liu, Jingxian; Liu, Ryan Wen; Xiong, Naixue; Wu, Kefeng; Kim, Tai-Hoon

2017-08-04

The Shipboard Automatic Identification System (AIS) is crucial for navigation safety and maritime surveillance, data mining and pattern analysis of AIS information have attracted considerable attention in terms of both basic research and practical applications. Clustering of spatio-temporal AIS trajectories can be used to identify abnormal patterns and mine customary route data for transportation safety. Thus, the capacities of navigation safety and maritime traffic monitoring could be enhanced correspondingly. However, trajectory clustering is often sensitive to undesirable outliers and is essentially more complex compared with traditional point clustering. To overcome this limitation, a multi-step trajectory clustering method is proposed in this paper for robust AIS trajectory clustering. In particular, the Dynamic Time Warping (DTW), a similarity measurement method, is introduced in the first step to measure the distances between different trajectories. The calculated distances, inversely proportional to the similarities, constitute a distance matrix in the second step. Furthermore, as a widely-used dimensional reduction method, Principal Component Analysis (PCA) is exploited to decompose the obtained distance matrix. In particular, the top k principal components with above 95% accumulative contribution rate are extracted by PCA, and the number of the centers k is chosen. The k centers are found by the improved center automatically selection algorithm. In the last step, the improved center clustering algorithm with k clusters is implemented on the distance matrix to achieve the final AIS trajectory clustering results. In order to improve the accuracy of the proposed multi-step clustering algorithm, an automatic algorithm for choosing the k clusters is developed according to the similarity distance. Numerous experiments on realistic AIS trajectory datasets in the bridge area waterway and Mississippi River have been implemented to compare our proposed method with

Cp2 TiX Complexes for Sustainable Catalysis in Single-Electron Steps.

Science.gov (United States)

Richrath, Ruben B; Olyschläger, Theresa; Hildebrandt, Sven; Enny, Daniel G; Fianu, Godfred D; Flowers, Robert A; Gansäuer, Andreas

2018-04-25

We present a combined electrochemical, kinetic, and synthetic study with a novel and easily accessible class of titanocene catalysts for catalysis in single-electron steps. The tailoring of the electronic properties of our Cp 2 TiX-catalysts that are prepared in situ from readily available Cp 2 TiX 2 is achieved by varying the anionic ligand X. Of the complexes investigated, Cp 2 TiOMs proved to be either equal or substantially superior to the best catalysts developed earlier. The kinetic and thermodynamic properties pertinent to catalysis have been determined. They allow a mechanistic understanding of the subtle interplay of properties required for an efficient oxidative addition and reduction. Therefore, our study highlights that efficient catalysts do not require the elaborate covalent modification of the cyclopentadienyl ligands. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Magnetic Beads-Based Sensor with Tailored Sensitivity for Rapid and Single-Step Amperometric Determination of miRNAs

Directory of Open Access Journals (Sweden)

Eva Vargas

2017-11-01

Full Text Available This work describes a sensitive amperometric magneto-biosensor for single-step and rapid determination of microRNAs (miRNAs. The developed strategy involves the use of direct hybridization of the target miRNA (miRNA-21 with a specific biotinylated DNA probe immobilized on streptavidin-modified magnetic beads (MBs, and labeling of the resulting heteroduplexes with a specific DNA–RNA antibody and the bacterial protein A (ProtA conjugated with an horseradish peroxidase (HRP homopolymer (Poly-HRP40 as an enzymatic label for signal amplification. Amperometric detection is performed upon magnetic capture of the modified MBs onto the working electrode surface of disposable screen-printed carbon electrodes (SPCEs using the H2O2/hydroquinone (HQ system. The magnitude of the cathodic signal obtained at −0.20 V (vs. the Ag pseudo-reference electrode demonstrated linear dependence with the concentration of the synthetic target miRNA over the 1.0 to 100 pM range. The method provided a detection limit (LOD of 10 attomoles (in a 25 μL sample without any target miRNA amplification in just 30 min (once the DNA capture probe-MBs were prepared. This approach shows improved sensitivity compared with that of biosensors constructed with the same anti-DNA–RNA Ab as capture instead of a detector antibody and further labeling with a Strep-HRP conjugate instead of the Poly-HRP40 homopolymer. The developed strategy involves a single step working protocol, as well as the possibility to tailor the sensitivity by enlarging the length of the DNA/miRNA heteroduplexes using additional probes and/or performing the labelling with ProtA conjugated with homopolymers prepared with different numbers of HRP molecules. The practical usefulness was demonstrated by determination of the endogenous levels of the mature target miRNA in 250 ng raw total RNA (RNAt extracted from human mammary epithelial normal (MCF-10A and cancer (MCF-7 cells and tumor tissues.

A reliable method for the counting and control of single ions for single-dopant controlled devices

International Nuclear Information System (INIS)

Shinada, T; Kurosawa, T; Nakayama, H; Zhu, Y; Hori, M; Ohdomari, I

2008-01-01

By 2016, transistor device size will be just 10 nm. However, a transistor that is doped at a typical concentration of 10 18 atoms cm -3 has only one dopant atom in the active channel region. Therefore, it can be predicted that conventional doping methods such as ion implantation and thermal diffusion will not be available ten years from now. We have been developing a single-ion implantation (SII) method that enables us to implant dopant ions one-by-one into semiconductors until the desired number is reached. Here we report a simple but reliable method to control the number of single-dopant atoms by detecting the change in drain current induced by single-ion implantation. The drain current decreases in a stepwise fashion as a result of the clusters of displaced Si atoms created by every single-ion incidence. This result indicates that the single-ion detection method we have developed is capable of detecting single-ion incidence with 100% efficiency. Our method potentially could pave the way to future single-atom devices, including a solid-state quantum computer

Online hyphenation of extraction, Sephadex LH-20 column chromatography, and high-speed countercurrent chromatography: A highly efficient strategy for the preparative separation of andrographolide from Andrographis paniculata in a single step.

Science.gov (United States)

Zhang, Ying-Qi; Wang, Shan-Shan; Han, Chao; Xu, Jin-Fang; Luo, Jian-Guang; Kong, Ling-Yi

2017-12-01

A novel isolation strategy, online hyphenation of ultrasonic extraction, Sephadex LH-20 column chromatography combined with high-speed countercurrent chromatography, was developed for pure compounds extraction and purification. Andrographolide from Andrographis paniculata was achieved only in a single step purification protocol via the present strategy. The crude powder was ultrasonic extracted and extraction was pumped into Sephadex LH-20 column directly to cut the nontarget fractions followed by the second-dimensional high-speed countercurrent chromatography, hyphenated by a six-port valve equipped at the post-end of Sephadex LH-20 column, for the final purification. The results yielded andrographolide with the amount of 1.02 mg and a purity of 98.5% in a single step, indicating that the present method is effective to harvest target compound from medicinal plant. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Convergence and Stability of the Split-Step θ-Milstein Method for Stochastic Delay Hopfield Neural Networks

Directory of Open Access Journals (Sweden)

Qian Guo

2013-01-01

Full Text Available A new splitting method designed for the numerical solutions of stochastic delay Hopfield neural networks is introduced and analysed. Under Lipschitz and linear growth conditions, this split-step θ-Milstein method is proved to have a strong convergence of order 1 in mean-square sense, which is higher than that of existing split-step θ-method. Further, mean-square stability of the proposed method is investigated. Numerical experiments and comparisons with existing methods illustrate the computational efficiency of our method.

One-step leapfrog ADI-FDTD method for simulating electromagnetic wave propagation in general dispersive media.

Science.gov (United States)

Wang, Xiang-Hua; Yin, Wen-Yan; Chen, Zhi Zhang David

2013-09-09

The one-step leapfrog alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method is reformulated for simulating general electrically dispersive media. It models material dispersive properties with equivalent polarization currents. These currents are then solved with the auxiliary differential equation (ADE) and then incorporated into the one-step leapfrog ADI-FDTD method. The final equations are presented in the form similar to that of the conventional FDTD method but with second-order perturbation. The adapted method is then applied to characterize (a) electromagnetic wave propagation in a rectangular waveguide loaded with a magnetized plasma slab, (b) transmission coefficient of a plane wave normally incident on a monolayer graphene sheet biased by a magnetostatic field, and (c) surface plasmon polaritons (SPPs) propagation along a monolayer graphene sheet biased by an electrostatic field. The numerical results verify the stability, accuracy and computational efficiency of the proposed one-step leapfrog ADI-FDTD algorithm in comparison with analytical results and the results obtained with the other methods.

Recursive regularization step for high-order lattice Boltzmann methods

Science.gov (United States)

Coreixas, Christophe; Wissocq, Gauthier; Puigt, Guillaume; Boussuge, Jean-François; Sagaut, Pierre

2017-09-01

A lattice Boltzmann method (LBM) with enhanced stability and accuracy is presented for various Hermite tensor-based lattice structures. The collision operator relies on a regularization step, which is here improved through a recursive computation of nonequilibrium Hermite polynomial coefficients. In addition to the reduced computational cost of this procedure with respect to the standard one, the recursive step allows to considerably enhance the stability and accuracy of the numerical scheme by properly filtering out second- (and higher-) order nonhydrodynamic contributions in under-resolved conditions. This is first shown in the isothermal case where the simulation of the doubly periodic shear layer is performed with a Reynolds number ranging from 104 to 106, and where a thorough analysis of the case at Re=3 ×104 is conducted. In the latter, results obtained using both regularization steps are compared against the Bhatnagar-Gross-Krook LBM for standard (D2Q9) and high-order (D2V17 and D2V37) lattice structures, confirming the tremendous increase of stability range of the proposed approach. Further comparisons on thermal and fully compressible flows, using the general extension of this procedure, are then conducted through the numerical simulation of Sod shock tubes with the D2V37 lattice. They confirm the stability increase induced by the recursive approach as compared with the standard one.

Methods for forming particles from single source precursors

Science.gov (United States)

Fox, Robert V [Idaho Falls, ID; Rodriguez, Rene G [Pocatello, ID; Pak, Joshua [Pocatello, ID

2011-08-23

Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.

Single step production of Cas9 mRNA for zygote injection.

Science.gov (United States)

Redel, Bethany K; Beaton, Benjamin P; Spate, Lee D; Benne, Joshua A; Murphy, Stephanie L; O'Gorman, Chad W; Spate, Anna M; Prather, Randall S; Wells, Kevin D

2018-03-01

Production of Cas9 mRNA in vitro typically requires the addition of a 5´ cap and 3´ polyadenylation. A plasmid was constructed that harbored the T7 promoter followed by the EMCV IRES and a Cas9 coding region. We hypothesized that the use of the metastasis associated lung adenocarcinoma transcript 1 (Malat1) triplex structure downstream of an IRES/Cas9 expression cassette would make polyadenylation of in vitro produced mRNA unnecessary. A sequence from the mMalat1 gene was cloned downstream of the IRES/Cas9 cassette described above. An mRNA concentration curve was constructed with either commercially available Cas9 mRNA or the IRES/ Cas9/triplex, by injection into porcine zygotes. Blastocysts were genotyped to determine if differences existed in the percent of embryos modified. The concentration curve identified differences due to concentration and RNA type injected. Single step production of Cas9 mRNA provides an alternative source of Cas9 for use in zygote injections.

A simple two-step method to fabricate highly transparent ITO/polymer nanocomposite films

International Nuclear Information System (INIS)

Liu, Haitao; Zeng, Xiaofei; Kong, Xiangrong; Bian, Shuguang; Chen, Jianfeng

2012-01-01

Highlights: ► A simple two-step method without further surface modification step was employed. ► ITO nanoparticles were easily to be uniformly dispersed in polymer matrix. ► ITO/polymer nanocomposite film had high transparency and UV/IR blocking properties. - Abstract: Transparent functional indium tin oxide (ITO)/polymer nanocomposite films were fabricated via a simple approach with two steps. Firstly, the functional monodisperse ITO nanoparticles were synthesized via a facile nonaqueous solvothermal method using bifunctional chemical agent (N-methyl-pyrrolidone, NMP) as the reaction solvent and surface modifier. Secondly, the ITO/acrylics polyurethane (PUA) nanocomposite films were fabricated by a simple sol-solution mixing method without any further surface modification step as often employed traditionally. Flower-like ITO nanoclusters with about 45 nm in diameter were mono-dispersed in ethyl acetate and each nanocluster was assembled by nearly spherical nanoparticles with primary size of 7–9 nm in diameter. The ITO nanoclusters exhibited an excellent dispersibility in polymer matrix of PUA, remaining their original size without any further agglomeration. When the loading content of ITO nanoclusters reached to 5 wt%, the transparent functional nanocomposite film featured a high transparency more than 85% in the visible light region (at 550 nm), meanwhile cutting off near-infrared radiation about 50% at 1500 nm and blocking UV ray about 45% at 350 nm. It could be potential for transparent functional coating materials applications.

Effect of increased exposure times on amount of residual monomer released from single-step self-etch adhesives.

Science.gov (United States)

Altunsoy, Mustafa; Botsali, Murat Selim; Tosun, Gonca; Yasar, Ahmet

2015-10-16

The aim of this study was to evaluate the effect of increased exposure times on the amount of residual Bis-GMA, TEGDMA, HEMA and UDMA released from single-step self-etch adhesive systems. Two adhesive systems were used. The adhesives were applied to bovine dentin surface according to the manufacturer's instructions and were polymerized using an LED curing unit for 10, 20 and 40 seconds (n = 5). After polymerization, the specimens were stored in 75% ethanol-water solution (6 mL). Residual monomers (Bis-GMA, TEGDMA, UDMA and HEMA) that were eluted from the adhesives (after 10 minutes, 1 hour, 1 day, 7 days and 30 days) were analyzed by high-performance liquid chromatography (HPLC). The data were analyzed using 1-way analysis of variance and Tukey HSD tests. Among the time periods, the highest amount of released residual monomers from adhesives was observed in the 10th minute. There were statistically significant differences regarding released Bis-GMA, UDMA, HEMA and TEGDMA between the adhesive systems (p<0.05). There were no significant differences among the 10, 20 and 40 second polymerization times according to their effect on residual monomer release from adhesives (p>0.05). Increasing the polymerization time did not have an effect on residual monomer release from single-step self-etch adhesives.

A two-step FEM-SEM approach for wave propagation analysis in cable structures

Science.gov (United States)

Zhang, Songhan; Shen, Ruili; Wang, Tao; De Roeck, Guido; Lombaert, Geert

2018-02-01

Vibration-based methods are among the most widely studied in structural health monitoring (SHM). It is well known, however, that the low-order modes, characterizing the global dynamic behaviour of structures, are relatively insensitive to local damage. Such local damage may be easier to detect by methods based on wave propagation which involve local high frequency behaviour. The present work considers the numerical analysis of wave propagation in cables. A two-step approach is proposed which allows taking into account the cable sag and the distribution of the axial forces in the wave propagation analysis. In the first step, the static deformation and internal forces are obtained by the finite element method (FEM), taking into account geometric nonlinear effects. In the second step, the results from the static analysis are used to define the initial state of the dynamic analysis which is performed by means of the spectral element method (SEM). The use of the SEM in the second step of the analysis allows for a significant reduction in computational costs as compared to a FE analysis. This methodology is first verified by means of a full FE analysis for a single stretched cable. Next, simulations are made to study the effects of damage in a single stretched cable and a cable-supported truss. The results of the simulations show how damage significantly affects the high frequency response, confirming the potential of wave propagation based methods for SHM.

Fast Synthesis of High Quality Biodiesel from ‘Waste Fish Oil’ by Single Step Transesterification

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Yogesh C. Sharma

2014-09-01

Full Text Available A large volume of fish wastes is produced on a daily basis in the Indian sub-continent. This abundant waste source could serve as an economic feedstock for bioenergy generation. In the present study, oil extracted from discarded fish parts was used for high quality biodiesel production. More specifically, a single step transesterification of ‘waste fishoil’ with methanol using sodium methoxide (CH3ONa as homogeneous catalyst under moderate operational conditions resulted in highly pure biodiesel of > 98% of fatty acid methyl ester (FAME content. Characterization was performed by Fourier Transform-Nuclear Magnetic Resonance (FT-NMR.

A brief introduction to single-molecule fluorescence methods

NARCIS (Netherlands)

Wildenberg, S.M.J.L.; Prevo, B.; Peterman, E.J.G.; Peterman, EJG; Wuite, GJL

2011-01-01

One of the more popular single-molecule approaches in biological science is single-molecule fluorescence microscopy, which is the subject of the following section of this volume. Fluorescence methods provide the sensitivity required to study biology on the single-molecule level, but they also allow

A brief introduction to single-molecule fluorescence methods

NARCIS (Netherlands)

van den Wildenberg, Siet M.J.L.; Prevo, Bram; Peterman, Erwin J.G.

2018-01-01

One of the more popular single-molecule approaches in biological science is single-molecule fluorescence microscopy, which will be the subject of the following section of this volume. Fluorescence methods provide the sensitivity required to study biology on the single-molecule level, but they also

An Improved Split-Step Wavelet Transform Method for Anomalous Radio Wave Propagation Modelling

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A. Iqbal

2014-12-01

Full Text Available Anomalous tropospheric propagation caused by ducting phenomenon is a major problem in wireless communication. Thus, it is important to study the behavior of radio wave propagation in tropospheric ducts. The Parabolic Wave Equation (PWE method is considered most reliable to model anomalous radio wave propagation. In this work, an improved Split Step Wavelet transform Method (SSWM is presented to solve PWE for the modeling of tropospheric propagation over finite and infinite conductive surfaces. A large number of numerical experiments are carried out to validate the performance of the proposed algorithm. Developed algorithm is compared with previously published techniques; Wavelet Galerkin Method (WGM and Split-Step Fourier transform Method (SSFM. A very good agreement is found between SSWM and published techniques. It is also observed that the proposed algorithm is about 18 times faster than WGM and provide more details of propagation effects as compared to SSFM.

Fully-Polymeric pH Sensor Realized by Means of a Single-Step Soft Embossing Technique

Science.gov (United States)

Fanzio, Paola; Chang, Chi-Tung; Skolimowski, Maciej; Tanzi, Simone; Sasso, Luigi

2017-01-01

We present here an electrochemical sensor microsystem for the monitoring of pH. The all-polymeric device is comprised of a cyclic olefin copolymer substrate, a 200 nm-thin patterned layer of conductive polymer (PEDOT), and a 70 nm electropolymerized layer of a pH sensitive conductive polymer (polyaniline). The patterning of the fluidic (microfluidic channels) and conductive (wiring and electrodes) functional elements was achieved with a single soft PDMS mold via a single embossing step process. A post-processing treatment with ethylene glycol assured the functional enhancement of the electrodes, as demonstrated via an electrical and electrochemical characterization. A surface modification of the electrodes was carried out, based on voltammetric electropolymerization, to obtain a thin layer of polyaniline. The mechanism for pH sensing is based on the redox reactions of the polyaniline layer caused by protonation. The sensing performance of the microsystem was finally validated by monitoring its potentiometric response upon exposure to a relevant range of pH. PMID:28531106

Fully-Polymeric pH Sensor Realized by Means of a Single-Step Soft Embossing Technique

Directory of Open Access Journals (Sweden)

Paola Fanzio

2017-05-01

Full Text Available We present here an electrochemical sensor microsystem for the monitoring of pH. The all-polymeric device is comprised of a cyclic olefin copolymer substrate, a 200 nm-thin patterned layer of conductive polymer (PEDOT, and a 70 nm electropolymerized layer of a pH sensitive conductive polymer (polyaniline. The patterning of the fluidic (microfluidic channels and conductive (wiring and electrodes functional elements was achieved with a single soft PDMS mold via a single embossing step process. A post-processing treatment with ethylene glycol assured the functional enhancement of the electrodes, as demonstrated via an electrical and electrochemical characterization. A surface modification of the electrodes was carried out, based on voltammetric electropolymerization, to obtain a thin layer of polyaniline. The mechanism for pH sensing is based on the redox reactions of the polyaniline layer caused by protonation. The sensing performance of the microsystem was finally validated by monitoring its potentiometric response upon exposure to a relevant range of pH.

Fully-Polymeric pH Sensor Realized by Means of a Single-Step Soft Embossing Technique.

Science.gov (United States)

Fanzio, Paola; Chang, Chi-Tung; Skolimowski, Maciej; Tanzi, Simone; Sasso, Luigi

2017-05-20

We present here an electrochemical sensor microsystem for the monitoring of pH. The all-polymeric device is comprised of a cyclic olefin copolymer substrate, a 200 nm-thin patterned layer of conductive polymer (PEDOT), and a 70 nm electropolymerized layer of a pH sensitive conductive polymer (polyaniline). The patterning of the fluidic (microfluidic channels) and conductive (wiring and electrodes) functional elements was achieved with a single soft PDMS mold via a single embossing step process. A post-processing treatment with ethylene glycol assured the functional enhancement of the electrodes, as demonstrated via an electrical and electrochemical characterization. A surface modification of the electrodes was carried out, based on voltammetric electropolymerization, to obtain a thin layer of polyaniline. The mechanism for pH sensing is based on the redox reactions of the polyaniline layer caused by protonation. The sensing performance of the microsystem was finally validated by monitoring its potentiometric response upon exposure to a relevant range of pH.

Analytic observations for the d=1+ 1 bridge site (or single-step) deposition model

International Nuclear Information System (INIS)

Evans, J.W.; Kang, H.C.

1991-01-01

Some exact results for a reversible version of the d=1+1 bridge site (or single-step) deposition model are presented. Exact steady-state properties are determined directly for finite systems with various mean slopes. These show explicitly how the asymptotic growth velocity and fluctuations are quenched as the slope approaches its maximum allowed value. Next, exact hierarchial equations for the dynamics are presented. For the special case of ''equilibrium growth,'' these are analyzed exactly at the pair-correlation level directly for an infinite system. This provided further insight into asymptotic scaling behavior. Finally, the above hierarchy is compared with one generated from a discrete form of the Kardar--Parisi--Zhang equations. Some differences are described

Nonlinear Stability and Convergence of Two-Step Runge-Kutta Methods for Volterra Delay Integro-Differential Equations

Directory of Open Access Journals (Sweden)

Haiyan Yuan

2013-01-01

Full Text Available This paper introduces the stability and convergence of two-step Runge-Kutta methods with compound quadrature formula for solving nonlinear Volterra delay integro-differential equations. First, the definitions of (k,l-algebraically stable and asymptotically stable are introduced; then the asymptotical stability of a (k,l-algebraically stable two-step Runge-Kutta method with 0step Runge-Kutta method is algebraically stable and diagonally stable and its generalized stage order is p, then the method with compound quadrature formula is D-convergent of order at least min{p,ν}, where ν depends on the compound quadrature formula.

Study on evaluation method for image quality of radiograph by step plate, (2)

International Nuclear Information System (INIS)

Terada, Yukihiro; Hirayama, Kazuo; Katoh, Mitsuaki.

1992-01-01

Recently, penetrameter sensitivity is used not only for the evaluation of radiographic image quality but also as a control method for examination conditions. However, it is necessary to take the parametric data for radiation quality in order to use it for the second purpose. The quantitative factor of radiation quality is determined by the absorption coefficient and the ratio of scattered radiation to transmitted radiation reaching the X-ray film. When the X-ray equipment changes in conducting the radiographic examination, these data must be measured in each case. This is a demerit in controlling examination conditions based on parametric data. As shown theoretically in the first report, the image quality value of a step plate which is defined by the density difference divided by film contrast and step plate thickness is useful to obtain the value of the radiation quality factor. This report deal with experimental investigation to measure it with the step plate. The result is showing that the value of the radiation quality factor calculated by the parametric data corresponded well with the image quality value measured by the step plate. Therefore, the convenient method to measure the value of the radiation quality factor has been established in order to control examination conditions in radiographic examination. (author)

A novel two-step optimization method for tandem and ovoid high-dose-rate brachytherapy treatment for locally advanced cervical cancer.

Science.gov (United States)

Sharma, Manju; Fields, Emma C; Todor, Dorin A

2015-01-01

To present a novel method allowing fast volumetric optimization of tandem and ovoid high-dose-rate treatments and to quantify its benefits. Twenty-seven CT-based treatment plans from 6 consecutive cervical cancer patients treated with four to five intracavitary tandem and ovoid insertions were used. Initial single-step optimized plans were manually optimized, approved, and delivered plans created with a goal to cover high-risk clinical target volume (HR-CTV) with D90 >90% and minimize rectum, bladder, and sigmoid D2cc. For the two-step optimized (TSO) plan, each single-step optimized plan was replanned adding a structure created from prescription isodose line to the existent physician delineated HR-CTV, rectum, bladder, and sigmoid. New, more rigorous dose-volume histogram constraints for the critical organs at risks (OARs) were used for the optimization. HR-CTV D90 and OAR D2ccs were evaluated in both plans. TSO plans had consistently smaller D2ccs for all three OARs while preserving HR-CTV D90. On plans with "excellent" CTV coverage, average D90 of 96% (91-102%), sigmoid, bladder, and rectum D2cc, respectively, reduced on average by 37% (16-73%), 28% (20-47%), and 27% (15-45%). Similar reductions were obtained on plans with "good" coverage, average D90 of 93% (90-99%). For plans with "inferior" coverage, average D90 of 81%, the coverage increased to 87% with concurrent D2cc reductions of 31%, 18%, and 11% for sigmoid, bladder, and rectum, respectively. The TSO can be added with minimal planning time increase but with the potential of dramatic and systematic reductions in OAR D2ccs and in some cases with concurrent increase in target dose coverage. These single-fraction modifications would be magnified over the course of four to five intracavitary insertions and may have real clinical implications in terms of decreasing both acute and late toxicities. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

A simple three step method for selective placement of organic groups in mesoporous silica thin films

Energy Technology Data Exchange (ETDEWEB)

Franceschini, Esteban A. [Gerencia Química, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, Av. Gral Paz 1499 (B1650KNA) San Martín, Buenos Aires (Argentina); Llave, Ezequiel de la; Williams, Federico J. [Departamento de Química Inorgánica, Analítica y Química Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, C1428EHA Buenos Aires (Argentina); Soler-Illia, Galo J.A.A., E-mail: galo.soler.illia@gmail.com [Departamento de Química Inorgánica, Analítica y Química Física and INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón II, C1428EHA Buenos Aires (Argentina); Instituto de Nanosistemas, Universidad Nacional de General San Martín, 25 de Mayo y Francia (1650) San Martín, Buenos Aires (Argentina)

2016-02-01

Selective functionalization of mesoporous silica thin films was achieved using a three step method. The first step consists in an outer surface functionalization, followed by washing off the structuring agent (second step), leaving the inner surface of the pores free to be functionalized in the third step. This reproducible method permits to anchor a volatile silane group in the outer film surface, and a second type of silane group in the inner surface of the pores. As a concept test we modified the outer surface of a mesoporous silica film with trimethylsilane (–Si–(CH{sub 3}){sub 3}) groups and the inner pore surface with propylamino (–Si–(CH{sub 2}){sub 3}–NH{sub 2}) groups. The obtained silica films were characterized by Environmental Ellipsometric Porosimetry (EEP), EDS, XPS, contact angle and electron microscopy. The selectively functionalized silica (SF) shows an amount of surface amino functions 4.3 times lower than the one-step functionalized (OSF) silica samples. The method presented here can be extended to a combination of silane chlorides and alkoxides as functional groups, opening up a new route toward the synthesis of multifunctional mesoporous thin films with precisely localized organic functions. - Highlights: • Selective functionalization of mesoporous silica thin films was achieved using a three step method. • A volatile silane group is anchored by evaporation on the outer film surface. • A second silane is deposited in the inner surface of the pores by post-grafting. • Contact angle, EDS and XPS measurements show different proportions of amino groups on both surfaces. • This method can be extended to a combination of silane chlorides and alkoxides functional groups.

The effect of step thickness on the surface diffusion of a Pt adatom

International Nuclear Information System (INIS)

Yang, Jianyu; Deng, Yonghe; Xiao, Gang; Hu, Wangyu; Chen, Shuguang

2009-01-01

The diffusion of a single Pt adatom on the Pt(1 1 1) surface with {1 1 1}-faceted steps is studied using a combination of molecular dynamics and the nudged elastic band method. The interatomic interactions are described with the analytic embedded atom method. The simulation indicates that before diffusion across the descending step, the adatom becomes trapped at the step edge, and has to overcome an energy barrier to return the plane's center. The energy barrier for adatom migration to the step edge is almost independent of step thickness. In addition, the step thickness dependence of the diffusion energy barrier for the adatom over descending and ascending steps edge is obtained. For a monolayer step, the upward diffusion of the adatom to the {1 1 1}-faceted steps is very rare as compared with the downward diffusion. However, the probability of the adatom to ascend the {1 1 1}-faceted steps increases with increasing step thickness. The calculated character temperatures indicate the three-dimensional pyramidal island on the clean Pt(1 1 1) surface can be formed at higher temperature

Fire-through Ag contact formation for crystalline Si solar cells using single-step inkjet printing.

Science.gov (United States)

Kim, Hyun-Gang; Cho, Sung-Bin; Chung, Bo-Mook; Huh, Joo-Youl; Yoon, Sam S

2012-04-01

Inkjet-printed Ag metallization is a promising method of forming front-side contacts on Si solar cells due to its non-contact printing nature and fine grid resolution. However, conventional Ag inks are unable to punch through the SiN(x) anti-reflection coating (ARC) layer on emitter Si surfaces. In this study, a novel formulation of Ag ink is examined for the formation of fire-through contacts on a SiN(x)-coated Si substrate using the single-step printing of Ag ink, followed by rapid thermal annealing at 800 degrees C. In order to formulate Ag inks with fire-through contact formation capabilities, a liquid etching agent was first formulated by dissolving metal nitrates in an organic solvent and then mixing the resulting solution with a commercial Ag nanoparticle ink at various volume ratios. During the firing process, the dissolved metal nitrates decomposed into metal oxides and acted in a similar manner to the glass frit contained in Ag pastes for screen-printed Ag metallization. The newly formulated ink with a 1 wt% loading ratio of metal oxides to Ag formed finely distributed Ag crystallites on the Si substrate after firing at 800 degrees C for 1 min.

SYSTEMATIZATION OF THE BASIC STEPS OF THE STEP-AEROBICS

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Darinka Korovljev

2011-03-01

Full Text Available Following the development of the powerful sport industry, in front of us appeared a lot of new opportunities for creating of the new programmes of exercising with certain requisites. One of such programmes is certainly step-aerobics. Step-aerobics can be defined as a type of aerobics consisting of the basic aerobic steps (basic steps applied in exercising on stepper (step bench, with a possibility to regulate its height. Step-aerobics itself can be divided into several groups, depending on the following: type of music, working methods and adopted knowledge of the attendants. In this work, the systematization of the basic steps in step-aerobics was made on the basis of the following criteria: steps origin, number of leg motions in stepping and relating the body support at the end of the step. Systematization of the basic steps of the step-aerobics is quite significant for making a concrete review of the existing basic steps, thus making creation of the step-aerobics lesson easier

LiLEDDA: A Six-Step Forum-Based Netnographic Research Method for Nursing Science

Directory of Open Access Journals (Sweden)

MARTIN SALZMANN-ERIKSON

2012-01-01

Full Text Available Internet research methods in nursing science are less developed than in other sciences. We choose to present an approach to conducting nursing research on an internet-based forum. This paper presents LiLEDDA, a six-step forum-based netnographic research method for nursing science. The steps consist of: 1. Literature review and identification of the research question(s; 2. Locating the field(s online; 3. Ethical considerations; 4. Data gathering; 5. Data analysis and interpretation; and 6. Abstractions and trustworthiness. Traditional research approaches are limiting when studying non-normative and non-mainstream life-worlds and their cultures. We argue that it is timely to develop more up-to-date research methods and study designs applicable to nursing science that reflect social developments and human living conditions that tend to be increasingly online-based.

Combined Effects of Numerical Method Type and Time Step on Water Stressed Actual Crop ET

Directory of Open Access Journals (Sweden)

B. Ghahraman

2016-02-01

Full Text Available Introduction: Actual crop evapotranspiration (Eta is important in hydrologic modeling and irrigation water management issues. Actual ET depends on an estimation of a water stress index and average soil water at crop root zone, and so depends on a chosen numerical method and adapted time step. During periods with no rainfall and/or irrigation, actual ET can be computed analytically or by using different numerical methods. Overal, there are many factors that influence actual evapotranspiration. These factors are crop potential evapotranspiration, available root zone water content, time step, crop sensitivity, and soil. In this paper different numerical methods are compared for different soil textures and different crops sensitivities. Materials and Methods: During a specific time step with no rainfall or irrigation, change in soil water content would be equal to evapotranspiration, ET. In this approach, however, deep percolation is generally ignored due to deep water table and negligible unsaturated hydraulic conductivity below rooting depth. This differential equation may be solved analytically or numerically considering different algorithms. We adapted four different numerical methods, as explicit, implicit, and modified Euler, midpoint method, and 3-rd order Heun method to approximate the differential equation. Three general soil types of sand, silt, and clay, and three different crop types of sensitive, moderate, and resistant under Nishaboor plain were used. Standard soil fraction depletion (corresponding to ETc=5 mm.d-1, pstd, below which crop faces water stress is adopted for crop sensitivity. Three values for pstd were considered in this study to cover the common crops in the area, including winter wheat and barley, cotton, alfalfa, sugar beet, saffron, among the others. Based on this parameter, three classes for crop sensitivity was considered, sensitive crops with pstd=0.2, moderate crops with pstd=0.5, and resistive crops with pstd=0

One-step method for the production of nanofluids

Science.gov (United States)

Kostic, Milivoje [Chicago, IL; Golubovic, Mihajlo [Chicago, IL; Hull, John R [Downers Grove, IL; Choi, Stephen U. S. [Napersville, IL

2010-05-18

A one step method and system for producing nanofluids by a particle-source evaporation and deposition of the evaporant into a base fluid. The base fluid such (i.e. ethylene glycol) is placed in a rotating cylindrical drum having an adjustable heater-boat-evaporator and heat exchanger-cooler apparatus. As the drum rotates, a thin liquid layer is formed on the inside surface of the drum. A heater-boat-evaporator having an evaporant material (particle-source) placed within its boat evaporator is adjustably positioned near a portion of the rotating thin liquid layer, the evaporant material being heated thereby evaporating a portion of the evaporant material, the evaporated material absorbed by the liquid film to form nanofluid.

Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

KAUST Repository

Pestana, Reynam C.

2009-01-01

We show that the wave equation solution using a conventional finite‐difference scheme, derived commonly by the Taylor series approach, can be derived directly from the rapid expansion method (REM). After some mathematical manipulation we consider an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second order time finite‐difference scheme that is frequently used in more conventional finite‐difference implementations. We then show that if we use more terms from the REM we can obtain a more accurate time integration of the wave field. Consequently, we have demonstrated that the REM is more accurate than the usual finite‐difference schemes and it provides a wave equation solution which allows us to march in large time steps without numerical dispersion and is numerically stable. We illustrate the method with post and pre stack migration results.

Novel two-step method to form silk fibroin fibrous hydrogel

International Nuclear Information System (INIS)

Ming, Jinfa; Li, Mengmeng; Han, Yuhui; Chen, Ying; Li, Han; Zuo, Baoqi; Pan, Fukui

2016-01-01

Hydrogels prepared by silk fibroin solution have been studied. However, mimicking the nanofibrous structures of extracellular matrix for fabricating biomaterials remains a challenge. Here, a novel two-step method was applied to prepare fibrous hydrogels using regenerated silk fibroin solution containing nanofibrils in a range of tens to hundreds of nanometers. When the gelation process of silk solution occurred, it showed a top-down type gel within 30 min. After gelation, silk fibroin fibrous hydrogels exhibited nanofiber network morphology with β-sheet structure. Moreover, the compressive stress and modulus of fibrous hydrogels were 31.9 ± 2.6 and 2.8 ± 0.8 kPa, respectively, which was formed using 2.0 wt.% concentration solutions. In addition, fibrous hydrogels supported BMSCs attachment and proliferation over 12 days. This study provides important insight in the in vitro processing of silk fibroin into useful new materials. - Highlights: • SF fibrous hydrogel was prepared by a novel two-step method. • SF solution containing nanofibrils in a range of tens to hundreds of nanometers was prepared. • Gelation process was top-down type gel with several minutes. • SF fibrous hydrogels exhibited nanofiber network morphology with β-sheet structure. • Fibrous hydrogels had higher compressive stresses superior to porous hydrogels.

Effects of phylogenetic reconstruction method on the robustness of species delimitation using single-locus data.

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Tang, Cuong Q; Humphreys, Aelys M; Fontaneto, Diego; Barraclough, Timothy G; Paradis, Emmanuel

2014-10-01

Coalescent-based species delimitation methods combine population genetic and phylogenetic theory to provide an objective means for delineating evolutionarily significant units of diversity. The generalised mixed Yule coalescent (GMYC) and the Poisson tree process (PTP) are methods that use ultrametric (GMYC or PTP) or non-ultrametric (PTP) gene trees as input, intended for use mostly with single-locus data such as DNA barcodes. Here, we assess how robust the GMYC and PTP are to different phylogenetic reconstruction and branch smoothing methods. We reconstruct over 400 ultrametric trees using up to 30 different combinations of phylogenetic and smoothing methods and perform over 2000 separate species delimitation analyses across 16 empirical data sets. We then assess how variable diversity estimates are, in terms of richness and identity, with respect to species delimitation, phylogenetic and smoothing methods. The PTP method generally generates diversity estimates that are more robust to different phylogenetic methods. The GMYC is more sensitive, but provides consistent estimates for BEAST trees. The lower consistency of GMYC estimates is likely a result of differences among gene trees introduced by the smoothing step. Unresolved nodes (real anomalies or methodological artefacts) affect both GMYC and PTP estimates, but have a greater effect on GMYC estimates. Branch smoothing is a difficult step and perhaps an underappreciated source of bias that may be widespread among studies of diversity and diversification. Nevertheless, careful choice of phylogenetic method does produce equivalent PTP and GMYC diversity estimates. We recommend simultaneous use of the PTP model with any model-based gene tree (e.g. RAxML) and GMYC approaches with BEAST trees for obtaining species hypotheses.

Evaluation of lung and chest wall mechanics during anaesthesia using the PEEP-step method.

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Persson, P; Stenqvist, O; Lundin, S

2018-04-01

Postoperative pulmonary complications are common. Between patients there are differences in lung and chest wall mechanics. Individualised mechanical ventilation based on measurement of transpulmonary pressures would be a step forward. A previously described method evaluates lung and chest wall mechanics from a change of ΔPEEP and calculation of change in end-expiratory lung volume (ΔEELV). The aim of the present study was to validate this PEEP-step method (PSM) during general anaesthesia by comparing it with the conventional method using oesophageal pressure (PES) measurements. In 24 lung healthy subjects (BMI 18.5-32), three different sizes of PEEP steps were performed during general anaesthesia and ΔEELVs were calculated. Transpulmonary driving pressure (ΔPL) for a tidal volume equal to each ΔEELV was measured using PES measurements and compared to ΔPEEP with limits of agreement and intraclass correlation coefficients (ICC). ΔPL calculated with both methods was compared with a Bland-Altman plot. Mean differences between ΔPEEP and ΔPL were mechanical properties among the lung healthy patients stresses the need for individualised ventilator settings based on measurements of lung and chest wall mechanics. The agreement between ΔPLs measured by the two methods during general anaesthesia suggests the use of the non-invasive PSM in this patient population. NCT 02830516. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Twinning processes in Cu-Al-Ni martensite single crystals investigated by neutron single crystal diffraction method

International Nuclear Information System (INIS)

Molnar, P.; Sittner, P.; Novak, V.; Lukas, P.

2008-01-01

A neutron single crystal diffraction method for inspecting the quality of martensite single crystals is introduced. True interface-free martensite single crystals are indispensable for, e.g. measurement of elastic constants of phases by ultrasonic techniques. The neutron diffraction method was used to detect and distinguish the presence of individual lattice correspondence variants of the 2H orthorhombic martensite phase in Cu-Al-Ni as well as to follow the activity of twinning processes during the deformation test on the martensite variant single crystals. When preparing the martensite single variant prism-shaped crystals by compression deformation method, typically a small fraction of second unwanted martensitic variant (compound twin) remains in the prism samples. Due to the very low stress (∼1 MPa) for the compound twinning in many shape memory alloys, it is quite difficult not only to deplete the martensite prisms of all internal interfaces but mainly to keep them in the martensite single variant state for a long time needed for further investigations

Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)

KAUST Repository

Pestana, Reynam C.; Stoffa, Paul L.

2009-01-01

an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second

Single droplet drying step characterization in microsphere preparation.

Science.gov (United States)

Al Zaitone, Belal; Lamprecht, Alf

2013-05-01

Spray drying processes are difficult to characterize since process parameters are not directly accessible. Acoustic levitation was used to investigate microencapsulation by spray drying on one single droplet facilitating the analyses of droplet behavior upon drying. Process parameters were simulated on a poly(lactide-co-glycolide)/ethyl acetate combination for microencapsulation. The results allowed quantifying the influence of process parameters such as temperature (0-40°C), polymer concentration (5-400 mg/ml), and droplet size (0.5-1.37 μl) on the drying time and drying kinetics as well as the particle morphology. The drying of polymer solutions at temperature of 21°C and concentration of 5 mg/ml, shows that the dimensionless particle diameter (Dp/D0) approaches 0.25 and the particle needs 350 s to dry. At 400 mg/ml, Dp/D0=0.8 and the drying time increases to one order of magnitude and a hollow particle is formed. The study demonstrates the benefit of using the acoustic levitator as a lab scale method to characterize and study the microparticle formation. This method can be considered as a helpful tool to mimic the full scale spray drying process by providing identical operational parameters such as air velocity, temperature, and variable droplet sizes. Copyright © 2013 Elsevier B.V. All rights reserved.

Coupling of Spinosad Fermentation and Separation Process via Two-Step Macroporous Resin Adsorption Method.

Science.gov (United States)

Zhao, Fanglong; Zhang, Chuanbo; Yin, Jing; Shen, Yueqi; Lu, Wenyu

2015-08-01

In this paper, a two-step resin adsorption technology was investigated for spinosad production and separation as follows: the first step resin addition into the fermentor at early cultivation period to decrease the timely product concentration in the broth; the second step of resin addition was used after fermentation to adsorb and extract the spinosad. Based on this, a two-step macroporous resin adsorption-membrane separation process for spinosad fermentation, separation, and purification was established. Spinosad concentration in 5-L fermentor increased by 14.45 % after adding 50 g/L macroporous at the beginning of fermentation. The established two-step macroporous resin adsorption-membrane separation process got the 95.43 % purity and 87 % yield for spinosad, which were both higher than that of the conventional crystallization of spinosad from aqueous phase that were 93.23 and 79.15 % separately. The two-step macroporous resin adsorption method has not only carried out the coupling of spinosad fermentation and separation but also increased spinosad productivity. In addition, the two-step macroporous resin adsorption-membrane separation process performs better in spinosad yield and purity.

Three-dimensional photonic crystals created by single-step multi-directional plasma etching.

Science.gov (United States)

Suzuki, Katsuyoshi; Kitano, Keisuke; Ishizaki, Kenji; Noda, Susumu

2014-07-14

We fabricate 3D photonic nanostructures by simultaneous multi-directional plasma etching. This simple and flexible method is enabled by controlling the ion-sheath in reactive-ion-etching equipment. We realize 3D photonic crystals on single-crystalline silicon wafers and show high reflectance (>95%) and low transmittance (photonic bandgap. Moreover, our method simply demonstrates Si-based 3D photonic crystals that show the photonic bandgap effect in a shorter wavelength range around 0.6 μm, where further fine structures are required.

Investigating the Effectiveness of Teaching Methods Based on a Four-Step Constructivist Strategy

Science.gov (United States)

Çalik, Muammer; Ayas, Alipaşa; Coll, Richard K.

2010-02-01

This paper reports on an investigation of the effectiveness an intervention using several different methods for teaching solution chemistry. The teaching strategy comprised a four-step approach derived from a constructivist view of learning. A sample consisting of 44 students (18 boys and 26 girls) was selected purposively from two different Grade 9 classes in the city of Trabzon, Turkey. Data collection employed a purpose-designed `solution chemistry concept test', consisting of 17 items, with the quantitative data from the survey supported by qualitative interview data. The findings suggest that using different methods embedded within the four-step constructivist-based teaching strategy enables students to refute some alternative conceptions, but does not completely eliminate student alternative conceptions for solution chemistry.

Controlling dental enamel-cavity ablation depth with optimized stepping parameters along the focal plane normal using a three axis, numerically controlled picosecond laser.

Science.gov (United States)

Yuan, Fusong; Lv, Peijun; Wang, Dangxiao; Wang, Lei; Sun, Yuchun; Wang, Yong

2015-02-01

The purpose of this study was to establish a depth-control method in enamel-cavity ablation by optimizing the timing of the focal-plane-normal stepping and the single-step size of a three axis, numerically controlled picosecond laser. Although it has been proposed that picosecond lasers may be used to ablate dental hard tissue, the viability of such a depth-control method in enamel-cavity ablation remains uncertain. Forty-two enamel slices with approximately level surfaces were prepared and subjected to two-dimensional ablation by a picosecond laser. The additive-pulse layer, n, was set to 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70. A three-dimensional microscope was then used to measure the ablation depth, d, to obtain a quantitative function relating n and d. Six enamel slices were then subjected to three dimensional ablation to produce 10 cavities, respectively, with additive-pulse layer and single-step size set to corresponding values. The difference between the theoretical and measured values was calculated for both the cavity depth and the ablation depth of a single step. These were used to determine minimum-difference values for both the additive-pulse layer (n) and single-step size (d). When the additive-pulse layer and the single-step size were set 5 and 45, respectively, the depth error had a minimum of 2.25 μm, and 450 μm deep enamel cavities were produced. When performing three-dimensional ablating of enamel with a picosecond laser, adjusting the timing of the focal-plane-normal stepping and the single-step size allows for the control of ablation-depth error to the order of micrometers.

Home-based step training using videogame technology in people with Parkinson's disease: a single-blinded randomised controlled trial.

Science.gov (United States)

Song, Jooeun; Paul, Serene S; Caetano, Maria Joana D; Smith, Stuart; Dibble, Leland E; Love, Rachelle; Schoene, Daniel; Menant, Jasmine C; Sherrington, Cathie; Lord, Stephen R; Canning, Colleen G; Allen, Natalie E

2018-03-01

To determine whether 12-week home-based exergame step training can improve stepping performance, gait and complementary physical and neuropsychological measures associated with falls in Parkinson's disease. A single-blinded randomised controlled trial. Community (experimental intervention), university laboratory (outcome measures). Sixty community-dwelling people with Parkinson's disease. Home-based step training using videogame technology. The primary outcomes were the choice stepping reaction time test and Functional Gait Assessment. Secondary outcomes included physical and neuropsychological measures associated with falls in Parkinson's disease, number of falls over six months and self-reported mobility and balance. Post intervention, there were no differences between the intervention ( n = 28) and control ( n = 25) groups in the primary or secondary outcomes except for the Timed Up and Go test, where there was a significant difference in favour of the control group ( P = 0.02). Intervention participants reported mobility improvement, whereas control participants reported mobility deterioration-between-group difference on an 11-point scale = 0.9 (95% confidence interval: -1.8 to -0.1, P = 0.03). Interaction effects between intervention and disease severity on physical function measures were observed ( P = 0.01 to P = 0.08) with seemingly positive effects for the low-severity group and potentially negative effects for the high-severity group. Overall, home-based exergame step training was not effective in improving the outcomes assessed. However, the improved physical function in the lower disease severity intervention participants as well as the self-reported improved mobility in the intervention group suggest home-based exergame step training may have benefits for some people with Parkinson's disease.

Experimental Investigation of a Base Isolation System Incorporating MR Dampers with the High-Order Single Step Control Algorithm

Directory of Open Access Journals (Sweden)

Weiqing Fu

2017-03-01

Full Text Available The conventional isolation structure with rubber bearings exhibits large deformation characteristics when subjected to infrequent earthquakes, which may lead to failure of the isolation layer. Although passive dampers can be used to reduce the layer displacement, the layer deformation and superstructure acceleration responses will increase in cases of fortification earthquakes or frequently occurring earthquakes. In addition to secondary damages and loss of life, such excessive displacement results in damages to the facilities in the structure. In order to overcome these shortcomings, this paper presents a structural vibration control system where the base isolation system is composed of rubber bearings with magnetorheological (MR damper and are regulated using the innovative control strategy. The high-order single-step algorithm with continuity and switch control strategies are applied to the control system. Shaking table test results under various earthquake conditions indicate that the proposed isolation method, compared with passive isolation technique, can effectively suppress earthquake responses for acceleration of superstructure and deformation within the isolation layer. As a result, this structural control method exhibits excellent performance, such as fast computation, generic real-time control, acceleration reduction and high seismic energy dissipation etc. The relative merits of the continuity and switch control strategies are also compared and discussed.

Comparison of the phenolic composition of fruit juices by single step gradient HPLC analysis of multiple components versus multiple chromatographic runs optimised for individual families.

Science.gov (United States)

Bremner, P D; Blacklock, C J; Paganga, G; Mullen, W; Rice-Evans, C A; Crozier, A

2000-06-01

After minimal sample preparation, two different HPLC methodologies, one based on a single gradient reversed-phase HPLC step, the other on multiple HPLC runs each optimised for specific components, were used to investigate the composition of flavonoids and phenolic acids in apple and tomato juices. The principal components in apple juice were identified as chlorogenic acid, phloridzin, caffeic acid and p-coumaric acid. Tomato juice was found to contain chlorogenic acid, caffeic acid, p-coumaric acid, naringenin and rutin. The quantitative estimates of the levels of these compounds, obtained with the two HPLC procedures, were very similar, demonstrating that either method can be used to analyse accurately the phenolic components of apple and tomato juices. Chlorogenic acid in tomato juice was the only component not fully resolved in the single run study and the multiple run analysis prior to enzyme treatment. The single run system of analysis is recommended for the initial investigation of plant phenolics and the multiple run approach for analyses where chromatographic resolution requires improvement.

Automated methods for single-stranded DNA isolation and dideoxynucleotide DNA sequencing reactions on a robotic workstation

International Nuclear Information System (INIS)

Mardis, E.R.; Roe, B.A.

1989-01-01

Automated procedures have been developed for both the simultaneous isolation of 96 single-stranded M13 chimeric template DNAs in less than two hours, and for simultaneously pipetting 24 dideoxynucleotide sequencing reactions on a commercially available laboratory workstation. The DNA sequencing results obtained by either radiolabeled or fluorescent methods are consistent with the premise that automation of these portions of DNA sequencing projects will improve the reproducibility of the DNA isolation and the procedures for these normally labor-intensive steps provides an approach for rapid acquisition of large amounts of high quality, reproducible DNA sequence data

s-Step Krylov Subspace Methods as Bottom Solvers for Geometric Multigrid

Energy Technology Data Exchange (ETDEWEB)

Williams, Samuel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lijewski, Mike [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Almgren, Ann [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Straalen, Brian Van [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Carson, Erin [Univ. of California, Berkeley, CA (United States); Knight, Nicholas [Univ. of California, Berkeley, CA (United States); Demmel, James [Univ. of California, Berkeley, CA (United States)

2014-08-14

Geometric multigrid solvers within adaptive mesh refinement (AMR) applications often reach a point where further coarsening of the grid becomes impractical as individual sub domain sizes approach unity. At this point the most common solution is to use a bottom solver, such as BiCGStab, to reduce the residual by a fixed factor at the coarsest level. Each iteration of BiCGStab requires multiple global reductions (MPI collectives). As the number of BiCGStab iterations required for convergence grows with problem size, and the time for each collective operation increases with machine scale, bottom solves in large-scale applications can constitute a significant fraction of the overall multigrid solve time. In this paper, we implement, evaluate, and optimize a communication-avoiding s-step formulation of BiCGStab (CABiCGStab for short) as a high-performance, distributed-memory bottom solver for geometric multigrid solvers. This is the first time s-step Krylov subspace methods have been leveraged to improve multigrid bottom solver performance. We use a synthetic benchmark for detailed analysis and integrate the best implementation into BoxLib in order to evaluate the benefit of a s-step Krylov subspace method on the multigrid solves found in the applications LMC and Nyx on up to 32,768 cores on the Cray XE6 at NERSC. Overall, we see bottom solver improvements of up to 4.2x on synthetic problems and up to 2.7x in real applications. This results in as much as a 1.5x improvement in solver performance in real applications.

The Step Method - Battling Identity Theft Using E-Retailers' Websites

Science.gov (United States)

Schulze, Marion; Shah, Mahmood H.

Identity theft is the fastest growing crime in the 21st century. This paper investigates firstly what well-known e-commerce organizations are communicating on their websites to address this issue. For this purpose we analyze secondary data (literature and websites of ten organizations). Secondly we investigate the good practice in this area and recommend practical steps. The key findings are that some organizations only publish minimum security information to comply with legal requirements. Others inform consumers on how they actively try to prevent identity theft, how consumers can protect themselves, and about supporting actions when identity theft related fraud actually happens. From these findings we developed the Support - Trust - Empowerment -Prevention (STEP) method. It is aimed at helping to prevent identity theft and dealing with consequences when it occurs. It can help organizations on gaining and keeping consumers’ trust which is so essential for e-retailers in a climate of rising fraud.

Complex single step skull reconstruction in Gorham's disease - a technical report and review of the literature.

Science.gov (United States)

Ohla, Victoria; Bayoumi, Ahmed B; Hefty, Markus; Anderson, Matthew; Kasper, Ekkehard M

2015-03-11

Gorham's disease is a rare osteolytic disorder characterized by progressive resorption of bone and replacement of osseous matrix by a proliferative non-neoplastic vascular or lymphatic tissue. A standardized treatment protocol has not yet been defined due to the unpredictable natural history of the disease and variable clinical presentations. No single treatment has proven to be superior in arresting the course of the disease. Trials have included surgery, radiation and medical therapies using drugs such as calcium salts, vitamin D supplements and hormones. We report on our advantageous experience in the management of this osteolyic disorder in a case when it affected only the skull vault. A brief review of pertinent literature about Gorham's disease with skull involvement is provided. A 25-year-old Caucasian male presented with a skull depression over the left fronto-temporal region. He noticed progressive enlargement of the skull defect associated with local pain and mild headache. Physical examination revealed a tender palpable depression of the fronto-temporal convexity. Conventional X-ray of the skull showed widespread loss of bone substance. Subsequent CT scans showed features of patchy erosions indicative of an underlying osteolysis. MRI also revealed marginal enhancement at the site of the defect. The patient was in need of a pathological diagnosis as well as complex reconstruction of the afflicted area. A density graded CT scan was done to determine the variable degrees of osteolysis and a custom made allograft was designed for cranioplasty preoperatively to allow for a single step excisional craniectomy with synchronous skull repair. Gorham's disease was diagnosed based on histopathological examination. No neurological deficit or wound complications were reported postoperatively. Over a two-year follow up period, the patient had no evidence of local recurrence or other systemic involvement. A single step excisional craniectomy and cranioplasty can be an

Hepatitis B virus DNA quantification with the three-in-one (3io) method allows accurate single-step differentiation of total HBV DNA and cccDNA in biopsy-size liver samples.

Science.gov (United States)

Taranta, Andrzej; Tien Sy, Bui; Zacher, Behrend Johan; Rogalska-Taranta, Magdalena; Manns, Michael Peter; Bock, Claus Thomas; Wursthorn, Karsten

2014-08-01

Hepatitis B virus (HBV) replicates via reverse transcription converting its partially double stranded genome into the covalently closed circular DNA (cccDNA). The long-lasting cccDNA serves as a replication intermediate in the nuclei of hepatocytes. It is an excellent, though evasive, parameter for monitoring the course of liver disease and treatment efficiency. To develop and test a new approach for HBV DNA quantification in serum and small-size liver samples. The p3io plasmid contains an HBV fragment and human β-actin gene (hACTB) as a standard. Respective TaqMan probes were labeled with different fluorescent dyes. A triplex real-time PCR for simultaneous quantification of total HBV DNA, cccDNA and hACTB could be established. Three-in-one method allows simultaneous analysis of 3 targets with a lower limit of quantification of 48 copies per 20 μl PCR reaction and a wide range of linearity (R(2)>0.99, pDNA samples from HBV infected patients. Total HBV DNA and cccDNA could be quantified in 32 and 22 of 33 FFPE preserved liver specimens, respectively. Total HBV DNA concentrations quantified by the 3io method remained comparable with Cobas TaqMan HBV Test v2.0. The three-in-one protocol allows the single step quantification of viral DNA in samples from different sources. Therefore lower sample input, faster data acquisition, a lowered error and significantly lower costs are the advantages of the method. Copyright © 2014 Elsevier B.V. All rights reserved.

Single-Step Transepithelial PRK vs Alcohol-Assisted PRK in Myopia and Compound Myopic Astigmatism Correction.

Science.gov (United States)

Kaluzny, Bartlomiej J; Cieslinska, Iwona; Mosquera, Samuel A; Verma, Shwetabh

2016-02-01

Transepithelial photorefractive keratectomy (tPRK), where both the epithelium and stroma are removed in a single-step, is a relatively new procedure of laser refractive error correction. This study compares the 3-month results of myopia and compound myopic astigmatism correction by tPRK or conventional alcohol-assisted PRK (aaPRK).This prospective, nonrandomized, case-control study recruited 148 consecutive patients; 93 underwent tPRK (173 eyes) and 55 aaPRK (103 eyes). Refractive results, predictability, safety, and efficacy were evaluated during the 3-month follow-up. The main outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and mean refractive spherical equivalent (MRSE).Mean preoperative MRSE was -4.30 ± 1.72 D and -4.33 ± 1.96 D, respectively (P = 0.87). The 3-month follow-up rate was 82.1% in the tPRK group (n = 145) and 86.4% in aaPRK group (n = 90), P = 0.81. Postoperative UDVA was 20/20 or better in 97% and 94% of eyes, respectively (P = 0.45). In the tPRK and aaPRK groups, respectively, 13% and 21% of eyes lost 1 line of CDVA, and 30% and 31% gained 1 or 2 lines (P = 0.48). Mean postoperative MRSE was -0.14 ± 0.26 D in the tPRK group and -0.12 ± 0.20 D in the aaPRK group (P = 0.9). The correlation between attempted versus achieved MRSE was equally high in both groups.Single-step transepithelial PRK and conventional PRK provide very similar results 3 months postoperatively. These procedures are predictable, effective, and safe for correction of myopia and compound myopic astigmatism.

Well-Defined Silica Supported Aluminum Hydride: Another Step Towards the Utopian Single Site Dream?

KAUST Repository

Werghi, Baraa; Bendjeriou-Sedjerari, Anissa; Sofack-Kreutzer, Julien; Jedidi, Abdesslem; Abou-Hamad, Edy; Cavallo, Luigi; Basset, Jean-Marie

2015-01-01

Reaction of triisobutylaluminum with SBA15700 at room temperature occurs by two parallel pathways involving either silanol or siloxane bridges. It leads to the formation of a well-defined bipodal [(≡SiO)2Al-CH2CH(CH3)2] 1a, silicon isobutyl [≡Si-CH2CH(CH3)2] 1b and a silicon hydride [≡Si-H] 1c. Their structural identity was characterized by FT-IR and advance solid-state NMR spectroscopies (1H, 13C, 29Si, 27Al and 2D multiple quantum), elemental and gas phase analysis, and DFT calculations. The reaction involves the formation of a highly reactive monopodal intermediate: [≡SiO-Al-[CH2CH(CH3)2]2], with evolution of isobutane. This intermediate undergoes two parallel routes: Transfer of either one isobutyl fragment or of one hydride to an adjacent silicon atom. Both processes occur by opening of a strained siloxane bridge, ≡Si-O-Si≡ but with two different mechanisms, showing that the reality of “single site” catalyst may be an utopia: DFT calculations indicate that isobutyl transfer occurs via a simple metathesis between the Al-isobutyl and O-Si bonds, while hydride transfer occurs via a two steps mechanism, the first one is a ß-H elimination to Al with elimination of isobutene, whereas the second is a metathesis step between the formed Al-H bond and a O-Si bond. Thermal treatment of 1a (at 250 °C) under high vacuum (10-5 mbar) generates Al-H through a ß-H elimination of isobutyl fragment. These supported well-defined Al-H which are highly stable with time, are tetra, penta and octa coordinated as demonstrated by IR and 27Al–1H J-HMQC NMR spectroscopy. All these observations indicate that surfaces atoms around the site of grafting play a considerable role in the reactivity of a single site system.

Well-Defined Silica Supported Aluminum Hydride: Another Step Towards the Utopian Single Site Dream?

KAUST Repository

Werghi, Baraa

2015-07-17

Reaction of triisobutylaluminum with SBA15700 at room temperature occurs by two parallel pathways involving either silanol or siloxane bridges. It leads to the formation of a well-defined bipodal [(≡SiO)2Al-CH2CH(CH3)2] 1a, silicon isobutyl [≡Si-CH2CH(CH3)2] 1b and a silicon hydride [≡Si-H] 1c. Their structural identity was characterized by FT-IR and advance solid-state NMR spectroscopies (1H, 13C, 29Si, 27Al and 2D multiple quantum), elemental and gas phase analysis, and DFT calculations. The reaction involves the formation of a highly reactive monopodal intermediate: [≡SiO-Al-[CH2CH(CH3)2]2], with evolution of isobutane. This intermediate undergoes two parallel routes: Transfer of either one isobutyl fragment or of one hydride to an adjacent silicon atom. Both processes occur by opening of a strained siloxane bridge, ≡Si-O-Si≡ but with two different mechanisms, showing that the reality of “single site” catalyst may be an utopia: DFT calculations indicate that isobutyl transfer occurs via a simple metathesis between the Al-isobutyl and O-Si bonds, while hydride transfer occurs via a two steps mechanism, the first one is a ß-H elimination to Al with elimination of isobutene, whereas the second is a metathesis step between the formed Al-H bond and a O-Si bond. Thermal treatment of 1a (at 250 °C) under high vacuum (10-5 mbar) generates Al-H through a ß-H elimination of isobutyl fragment. These supported well-defined Al-H which are highly stable with time, are tetra, penta and octa coordinated as demonstrated by IR and 27Al–1H J-HMQC NMR spectroscopy. All these observations indicate that surfaces atoms around the site of grafting play a considerable role in the reactivity of a single site system.

Shutdown Dose Rate Analysis Using the Multi-Step CADIS Method

International Nuclear Information System (INIS)

Ibrahim, Ahmad M.; Peplow, Douglas E.; Peterson, Joshua L.; Grove, Robert E.

2015-01-01

The Multi-Step Consistent Adjoint Driven Importance Sampling (MS-CADIS) hybrid Monte Carlo (MC)/deterministic radiation transport method was proposed to speed up the shutdown dose rate (SDDR) neutron MC calculation using an importance function that represents the neutron importance to the final SDDR. This work applied the MS-CADIS method to the ITER SDDR benchmark problem. The MS-CADIS method was also used to calculate the SDDR uncertainty resulting from uncertainties in the MC neutron calculation and to determine the degree of undersampling in SDDR calculations because of the limited ability of the MC method to tally detailed spatial and energy distributions. The analysis that used the ITER benchmark problem compared the efficiency of the MS-CADIS method to the traditional approach of using global MC variance reduction techniques for speeding up SDDR neutron MC calculation. Compared to the standard Forward-Weighted-CADIS (FW-CADIS) method, the MS-CADIS method increased the efficiency of the SDDR neutron MC calculation by 69%. The MS-CADIS method also increased the fraction of nonzero scoring mesh tally elements in the space-energy regions of high importance to the final SDDR

Development of interface between MCNP-FISPACT-MCNP (IPR-MFM) based on rigorous two step method

International Nuclear Information System (INIS)

Shaw, A.K.; Swami, H.L.; Danani, C.

2015-01-01

In this work we present the development of interface tool between MCNP-FISPACT-MCNP (MFM) based on Rigorous Two Step method for the shutdown dose rate (SDDR) calculation. The MFM links MCNP radiation transport and the FISPACT inventory code through a suitable coupling scheme. MFM coupling scheme has three steps. In first step it picks neutron spectrum and total flux from MCNP output file to use as input parameter for FISPACT. It prepares the FISPACT input files by using irradiation history, neutron flux and neutron spectrum and then execute the FISPACT input file in the second step. Third step of MFM coupling scheme extracts the decay gammas from the FISPACT output file and prepares MCNP input file for decay gamma transport followed by execution of MCNP input file and estimation of SDDR. Here detailing of MFM methodology and flow scheme has been described. The programming language PYTHON has been chosen for this development of the coupling scheme. A complete loop of MCNP-FISPACT-MCNP has been developed to handle the simplified geometrical problems. For validation of MFM interface a manual cross-check has been performed which shows good agreements. The MFM interface also has been validated with exiting MCNP-D1S method for a simple geometry with 14 MeV cylindrical neutron source. (author)

Study of CdTe quantum dots grown using a two-step annealing method

Science.gov (United States)

Sharma, Kriti; Pandey, Praveen K.; Nagpal, Swati; Bhatnagar, P. K.; Mathur, P. C.

2006-02-01

High size dispersion, large average radius of quantum dot and low-volume ratio has been a major hurdle in the development of quantum dot based devices. In the present paper, we have grown CdTe quantum dots in a borosilicate glass matrix using a two-step annealing method. Results of optical characterization and the theoretical model of absorption spectra have shown that quantum dots grown using two-step annealing have lower average radius, lesser size dispersion, higher volume ratio and higher decrease in bulk free energy as compared to quantum dots grown conventionally.

Single-step generation of gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9.

Science.gov (United States)

Matsunaga, Taichi; Yamashita, Jun K

2014-02-07

Specific gene knockout and rescue experiments are powerful tools in developmental and stem cell biology. Nevertheless, the experiments require multiple steps of molecular manipulation for gene knockout and subsequent rescue procedures. Here we report an efficient and single step strategy to generate gene knockout-rescue system in pluripotent stem cells by promoter insertion with CRISPR/Cas9 genome editing technology. We inserted a tetracycline-regulated inducible gene promoter (tet-OFF/TRE-CMV) upstream of the endogenous promoter region of vascular endothelial growth factor receptor 2 (VEGFR2/Flk1) gene, an essential gene for endothelial cell (EC) differentiation, in mouse embryonic stem cells (ESCs) with homologous recombination. Both homo- and hetero-inserted clones were efficiently obtained through a simple selection with a drug-resistant gene. The insertion of TRE-CMV promoter disrupted endogenous Flk1 expression, resulting in null mutation in homo-inserted clones. When the inserted TRE-CMV promoter was activated with doxycycline (Dox) depletion, Flk1 expression was sufficiently recovered from the downstream genomic Flk1 gene. Whereas EC differentiation was almost completely perturbed in homo-inserted clones, Flk1 rescue with TRE-CMV promoter activation restored EC appearance, indicating that phenotypic changes in EC differentiation can be successfully reproduced with this knockout-rescue system. Thus, this promoter insertion strategy with CRISPR/Cas9 would be a novel attractive method for knockout-rescue experiments. Copyright © 2014 Elsevier Inc. All rights reserved.

Czochralski method of growing single crystals. State-of-art

International Nuclear Information System (INIS)

Bukowski, A.; Zabierowski, P.

1999-01-01

Modern Czochralski method of single crystal growing has been described. The example of Czochralski process is given. The advantages that caused the rapid progress of the method have been presented. The method limitations that motivated the further research and new solutions are also presented. As the example two different ways of the technique development has been described: silicon single crystals growth in the magnetic field; continuous liquid feed of silicon crystals growth. (author)

One-step synthesis of chlorinated graphene by plasma enhanced chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

Fan, Liwei; Zhang, Hui; Zhang, Pingping; Sun, Xuhui, E-mail: xhsun@suda.edu.cn

2015-08-30

Highlights: • We developed a simple approach to synthesize the single layer chlorinated graphene. • CuCl{sub 2} on Cu surface is used as Cl source under the plasma treatment. • The formation of covalent C−Cl bond has been investigated by Raman and XPS. • Raman results indicate the p-type doping effect of chlorination. - Abstract: We developed an approach to synthesize the chlorinated single layer graphene (Cl-G) by one-step plasma enhanced chemical vapor deposition. Copper foil was simply treated with hydrochloric acid and then CuCl{sub 2} formed on the surface was used as Cl source under the assistance of plasma treatment. Compared with other two-step methods by post plasma/photochemical treatment of CVD-grown single layer graphene (SLG), one-step Cl-G synthesis approach is quite straightforward and effective. X-ray photoelectron spectroscopy (XPS) revealed that ∼2.45 atom% Cl remained in SLG. Compared with the pristine SLG, the obvious blue shifts of G band and 2D band along with the appearance of D’ band and D + G band in the Raman spectra indicate p-type doping of Cl-G.

The UIC 406 capacity method used on single track sections

DEFF Research Database (Denmark)

Landex, Alex; Kaas, Anders H.; Jacobsen, Erik M.

2007-01-01

This paper describes the relatively new UIC 406 capacity method which is an easy and effective way of calculating capacity consumption on railway lines. However, it is possible to expound the method in different ways which can lead to different capacity consumptions. This paper describes the UIC...... 406 method for single track lines and how it is expounded in Denmark. Many capacity analyses using the UIC 406 capacity method for double track lines have been carried out and presented internationally but only few capacity analyses using the UIC 406 capacity method on single track lines have been...... presented. Therefore, the differences between capacity analysis for double track lines and single track lines are discussed in the beginning of this paper. Many of the principles of the UIC 406 capacity analyses on double track lines can be used on single track lines – at least when more than one train...

Evaluating tamsulosin hydrochloride-released microparticles prepared using single-step matrix coating.

Science.gov (United States)

Maeda, Atsushi; Shinoda, Tatsuki; Ito, Naoki; Baba, Keizo; Oku, Naoto; Mizumoto, Takao

2011-04-15

The objective of the present study was to determine the optimum composition for sustained-release of tamsulosin hydrochloride from microparticles intended for orally disintegrating tablets. Microparticles were prepared from an aqueous ethylcellulose dispersion (Aquacoa®), and an aqueous copolymer based on ethyl acrylate and methyl methacrylate dispersion (Eudragit®) NE30D), with microcrystalline cellulose as core particles with a fluidized bed coating process. Prepared microparticles were about 200 μm diameter and spherical. The microparticles were evaluated for in vitro drug release and in vivo absorption to assess bioequivalence in a commercial product, Harnal® pellets. The optimum ratio of Aquacoat® and Eudragit® NE30D in the matrix was 9:1. We observed similar drug release profiles in microparticles and Harnal® pellets. Higuchi model analysis of the in vitro drug release from microparticles was linear up to 80% release, typical of Fickian diffusion sustained-release profile. The in vivo absorption properties from microparticles were comparable to Harnal® pellets, and there was a linear relationship between in vitro drug release and in vivo drug release. In conclusion, this development produces microparticles in single-step coating, that provided a sustained-release of tamsulosin hydrochloride comparable to Harnal® pellets. Copyright © 2011 Elsevier B.V. All rights reserved.

Catalysts, methods of making catalysts, and methods of use

KAUST Repository

Renard, Laetitia; El Eter, Mohamad; Caps, Valerie; Basset, Jean-Marie

2014-01-01

Embodiments of the present disclosure provide for catalysts, methods of making catalysts, methods of using catalysts, and the like. In an embodiment, the method of making the catalysts can be performed in a single step with a metal nanoparticle precursor and a metal oxide precursor, where a separate stabilizing agent is not needed.

Catalysts, methods of making catalysts, and methods of use

KAUST Repository

Renard, Laetitia

2014-03-06

Embodiments of the present disclosure provide for catalysts, methods of making catalysts, methods of using catalysts, and the like. In an embodiment, the method of making the catalysts can be performed in a single step with a metal nanoparticle precursor and a metal oxide precursor, where a separate stabilizing agent is not needed.

Development of nondestructive screening methods for single kernel characterization of wheat

DEFF Research Database (Denmark)

Nielsen, J.P.; Pedersen, D.K.; Munck, L.

2003-01-01

predictability. However, by applying an averaging approach, in which single seed replicate measurements are mathematically simulated, a very good NIT prediction model was achieved. This suggests that the single seed NIT spectra contain hardness information, but that a single seed hardness method with higher......The development of nondestructive screening methods for single seed protein, vitreousness, density, and hardness index has been studied for single kernels of European wheat. A single kernel procedure was applied involving, image analysis, near-infrared transmittance (NIT) spectroscopy, laboratory...

Development of two dimensional electrophoresis method using single chain DNA

International Nuclear Information System (INIS)

Ikeda, Junichi; Hidaka, So

1998-01-01

By combining a separation method due to molecular weight and a method to distinguish difference of mono-bases, it was aimed to develop a two dimensional single chain DNA labeled with Radioisotope (RI). From electrophoretic pattern difference of parent and variant strands, it was investigated to isolate the root module implantation control gene. At first, a Single Strand Conformation Polymorphism (SSCP) method using concentration gradient gel was investigated. As a result, it was formed that intervals between double chain and single chain DNAs expanded, but intervals of both single chain DNAs did not expand. On next, combination of non-modified acrylic amide electrophoresis method and Denaturing Gradient-Gel Electrophoresis (DGGE) method was examined. As a result, hybrid DNA developed by two dimensional electrophoresis arranged on two lines. But, among them a band of DNA modified by high concentration of urea could not be found. Therefore, in this fiscal year's experiments, no preferable result could be obtained. By the used method, it was thought to be impossible to detect the differences. (G.K.)

Bioconversion of starch to ethanol in a single-step process by coculture of amylolytic yeasts and Saccharomyces cerevisiae 21

Energy Technology Data Exchange (ETDEWEB)

Verma, G.; Singh, D.; Chaudhary, K. [CCS Haryana Agricultural Univ., Hisar (India). Dept. of Biotechnology and Molecular Biology; Nigam, P. [Ulster Univ., Coleraine, Northern Ireland (United Kingdom). School of Applied Biological and Chemical Sciences

2000-05-01

Ethanol production by a coculture of Saccharomyces diastaticus and Saccharomyces cerevisiae 21 was 24.8 g/l using raw unhydrolysed starch in a single-step fermentation. This was 48% higher than the yield obtained with the monoculture of S. diastaticus (16.8 g/l). The maximum ethanol fermentation efficiency was achieved (93% of the theoretical value) using 60 g/l starch concentration. In another coculture fermentation with E. capsularis and S. cerevisiae 21, maximum ethanol yield was 16.0 g/l, higher than the yield with the monoculture of Endomycopsis capsularis. In batch fermentations using cocultures maximum ethanol production occurred in 48 h of fermentation at 30{sup o}C using 60 g/l starch. Fermentation efficiency was found lower in a two-step process using {alpha}-amylase and glucoamylase-treated starch. (Author)

A Method of MPPT Control Based on Power Variable Step-size in Photovoltaic Converter System

Directory of Open Access Journals (Sweden)

Xu Hui-xiang

2016-01-01

Full Text Available Since the disadvantage of traditional MPPT algorithms of variable step-size, proposed power tracking based on variable step-size with the advantage method of the constant-voltage and the perturb-observe (P&O[1-3]. The control strategy modify the problem of voltage fluctuation caused by perturb-observe method, at the same time, introducing the advantage of constant-voltage method and simplify the circuit topology. With the theoretical derivation, control the output power of photovoltaic modules to change the duty cycle of main switch. Achieve the maximum power stabilization output, reduce the volatility of energy loss effectively, and improve the inversion efficiency[3,4]. Given the result of experimental test based theoretical derivation and the curve of MPPT when the prototype work.

Single banking supervision and the single supervisory mechanism

Directory of Open Access Journals (Sweden)

Gheorghe, C. A.

2013-06-01

Full Text Available A resolution seems to have been found for the banking crisis. The first steps have been made towards the construction of the Economic and Monetary Union, steps involving the single supervision of banks, in order to avoid the discount of a new financial crisis on the expense of the EU state members. The Single Supervisory Mechanism – SSM is to become effective as of March 1, 2014, at the earliest.

A direct, single-step plasma arc-vitreous ceramic process for stabilizing spent nuclear fuels, sludges, and associated wastes

International Nuclear Information System (INIS)

Feng, X.; Einziger, R.E.; Eschenbach, R.C.

1997-01-01

A single-step plasma arc-vitreous ceramic (PAVC) process is described for converting spent nuclear fuel (SNF), SNF sludges, and associated wastes into a vitreous ceramic waste form. This proposed technology is built on extensive experience of nuclear waste form development and nuclear waste treatment using the commercially available plasma arc centrifugal (PAC) system. SNF elements will be loaded directly into a PAC furnace with minimum additives and converted into vitreous ceramics with up to 90 wt% waste loading. The vitreous ceramic waste form should meet the functional requirements for borosilicate glasses for permanent disposal in a geologic repository and for interim storage. Criticality safety would be ensured through the use of batch modes, and controlling the amount of fuel processed in one batch. The minimum requirements on SNF characterization and pretreatment, the one-step process, and minimum secondary waste generation may reduce treatment duration, radiation exposure, and treatment cost

The Effect of Phosphoric Acid Pre-etching Times on Bonding Performance and Surface Free Energy with Single-step Self-etch Adhesives.

Science.gov (United States)

Tsujimoto, A; Barkmeier, W W; Takamizawa, T; Latta, M A; Miyazaki, M

2016-01-01

The purpose of this study was to evaluate the effect of phosphoric acid pre-etching times on shear bond strength (SBS) and surface free energy (SFE) with single-step self-etch adhesives. The three single-step self-etch adhesives used were: 1) Scotchbond Universal Adhesive (3M ESPE), 2) Clearfil tri-S Bond (Kuraray Noritake Dental), and 3) G-Bond Plus (GC). Two no pre-etching groups, 1) untreated enamel and 2) enamel surfaces after ultrasonic cleaning with distilled water for 30 seconds to remove the smear layer, were prepared. There were four pre-etching groups: 1) enamel surfaces were pre-etched with phosphoric acid (Etchant, 3M ESPE) for 3 seconds, 2) enamel surfaces were pre-etched for 5 seconds, 3) enamel surfaces were pre-etched for 10 seconds, and 4) enamel surfaces were pre-etched for 15 seconds. Resin composite was bonded to the treated enamel surface to determine SBS. The SFEs of treated enamel surfaces were determined by measuring the contact angles of three test liquids. Scanning electron microscopy was used to examine the enamel surfaces and enamel-adhesive interface. The specimens with phosphoric acid pre-etching showed significantly higher SBS and SFEs than the specimens without phosphoric acid pre-etching regardless of the adhesive system used. SBS and SFEs did not increase for phosphoric acid pre-etching times over 3 seconds. There were no significant differences in SBS and SFEs between the specimens with and without a smear layer. The data suggest that phosphoric acid pre-etching of ground enamel improves the bonding performance of single-step self-etch adhesives, but these bonding properties do not increase for phosphoric acid pre-etching times over 3 seconds.

GNSS Single Frequency, Single Epoch Reliable Attitude Determination Method with Baseline Vector Constraint

Directory of Open Access Journals (Sweden)

Ang Gong

2015-12-01

Full Text Available For Global Navigation Satellite System (GNSS single frequency, single epoch attitude determination, this paper proposes a new reliable method with baseline vector constraint. First, prior knowledge of baseline length, heading, and pitch obtained from other navigation equipment or sensors are used to reconstruct objective function rigorously. Then, searching strategy is improved. It substitutes gradually Enlarged ellipsoidal search space for non-ellipsoidal search space to ensure correct ambiguity candidates are within it and make the searching process directly be carried out by least squares ambiguity decorrelation algorithm (LAMBDA method. For all vector candidates, some ones are further eliminated by derived approximate inequality, which accelerates the searching process. Experimental results show that compared to traditional method with only baseline length constraint, this new method can utilize a priori baseline three-dimensional knowledge to fix ambiguity reliably and achieve a high success rate. Experimental tests also verify it is not very sensitive to baseline vector error and can perform robustly when angular error is not great.

Methods of forming single source precursors, methods of forming polymeric single source precursors, and single source precursors formed by such methods

Science.gov (United States)

Fox, Robert V.; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin; Margulieux, Kelsey R.; Holland, Andrew W.

2014-09-09

Methods of forming single source precursors (SSPs) include forming intermediate products having the empirical formula 1/2{L.sub.2N(.mu.-X).sub.2M'X.sub.2}.sub.2, and reacting MER with the intermediate products to form SSPs of the formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2, wherein L is a Lewis base, M is a Group IA atom, N is a Group IB atom, M' is a Group IIIB atom, each E is a Group VIB atom, each X is a Group VIIA atom or a nitrate group, and each R group is an alkyl, aryl, vinyl, (per)fluoro alkyl, (per)fluoro aryl, silane, or carbamato group. Methods of forming polymeric or copolymeric SSPs include reacting at least one of HE.sup.1R.sup.1E.sup.1H and MER with one or more substances having the empirical formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2 or L.sub.2N(.mu.-X).sub.2M'(X).sub.2 to form a polymeric or copolymeric SSP. New SSPs and intermediate products are formed by such methods.

Research on the range side lobe suppression method for modulated stepped frequency radar signals

Science.gov (United States)

Liu, Yinkai; Shan, Tao; Feng, Yuan

2018-05-01

The magnitude of time-domain range sidelobe of modulated stepped frequency radar affects the imaging quality of inverse synthetic aperture radar (ISAR). In this paper, the cause of high sidelobe in modulated stepped frequency radar imaging is analyzed first in real environment. Then, the chaos particle swarm optimization (CPSO) is used to select the amplitude and phase compensation factors according to the minimum sidelobe criterion. Finally, the compensated one-dimensional range images are obtained. Experimental results show that the amplitude-phase compensation method based on CPSO algorithm can effectively reduce the sidelobe peak value of one-dimensional range images, which outperforms the common sidelobe suppression methods and avoids the coverage of weak scattering points by strong scattering points due to the high sidelobes.

A two-step method for fast and reliable EUV mask metrology

Science.gov (United States)

Helfenstein, Patrick; Mochi, Iacopo; Rajendran, Rajeev; Yoshitake, Shusuke; Ekinci, Yasin

2017-03-01

One of the major obstacles towards the implementation of extreme ultraviolet lithography for upcoming technology nodes in semiconductor industry remains the realization of a fast and reliable detection methods patterned mask defects. We are developing a reflective EUV mask-scanning lensless imaging tool (RESCAN), installed at the Swiss Light Source synchrotron at the Paul Scherrer Institut. Our system is based on a two-step defect inspection method. In the first step, a low-resolution defect map is generated by die to die comparison of the diffraction patterns from areas with programmed defects, to those from areas that are known to be defect-free on our test sample. In a later stage, a die to database comparison will be implemented in which the measured diffraction patterns will be compared to those calculated directly from the mask layout. This Scattering Scanning Contrast Microscopy technique operates purely in the Fourier domain without the need to obtain the aerial image and, given a sufficient signal to noise ratio, defects are found in a fast and reliable way, albeit with a location accuracy limited by the spot size of the incident illumination. Having thus identified rough locations for the defects, a fine scan is carried out in the vicinity of these locations. Since our source delivers coherent illumination, we can use an iterative phase-retrieval method to reconstruct the aerial image of the scanned area with - in principle - diffraction-limited resolution without the need of an objective lens. Here, we will focus on the aerial image reconstruction technique and give a few examples to illustrate the capability of the method.

Solving delay differential equations in S-ADAPT by method of steps.

Science.gov (United States)

Bauer, Robert J; Mo, Gary; Krzyzanski, Wojciech

2013-09-01

S-ADAPT is a version of the ADAPT program that contains additional simulation and optimization abilities such as parametric population analysis. S-ADAPT utilizes LSODA to solve ordinary differential equations (ODEs), an algorithm designed for large dimension non-stiff and stiff problems. However, S-ADAPT does not have a solver for delay differential equations (DDEs). Our objective was to implement in S-ADAPT a DDE solver using the methods of steps. The method of steps allows one to solve virtually any DDE system by transforming it to an ODE system. The solver was validated for scalar linear DDEs with one delay and bolus and infusion inputs for which explicit analytic solutions were derived. Solutions of nonlinear DDE problems coded in S-ADAPT were validated by comparing them with ones obtained by the MATLAB DDE solver dde23. The estimation of parameters was tested on the MATLB simulated population pharmacodynamics data. The comparison of S-ADAPT generated solutions for DDE problems with the explicit solutions as well as MATLAB produced solutions which agreed to at least 7 significant digits. The population parameter estimates from using importance sampling expectation-maximization in S-ADAPT agreed with ones used to generate the data. Published by Elsevier Ireland Ltd.

Development and Single-Laboratory Validation of a Liquid Chromatography Tandem Mass Spectrometry Method for Quantitation of Tetrodotoxin in Mussels and Oysters.

Science.gov (United States)

Turner, Andrew D; Boundy, Michael J; Rapkova, Monika Dhanji

2017-09-01

In recent years, evidence has grown for the presence of tetrodotoxin (TTX) in bivalve mollusks, leading to the potential for consumers of contaminated products to be affected by Tetrodotoxin Shellfish Poisoning (TSP). A single-laboratory validation was conducted for the hydrophilic interaction LC (HILIC) tandem MS (MS/MS) analysis of TTX in common mussels and Pacific oysters-the bivalve species that have been found to contain TTXs in the United Kingdom in recent years. The method consists of a single-step dispersive extraction in 1% acetic acid, followed by a carbon SPE cleanup step before dilution and instrumental analysis. The full method was developed as a rapid tool for the quantitation of TTX, as well as for the associated analogs 4-epi-TTX; 5,6,11-trideoxy TTX; 11-nor TTX-6-ol; 5-deoxy TTX; and 4,9-anhydro TTX. The method can also be run as the acquisition of TTX together with paralytic shellfish toxins. Results demonstrated acceptable method performance characteristics for specificity, linearity, recovery, ruggedness, repeatability, matrix variability, and within-laboratory reproducibility for the analysis of TTX. The LOD and LOQ were fit-for-purpose in comparison to the current action limit for TTX enforced in The Netherlands. In addition, aspects of method performance (LOD, LOQ, and within-laboratory reproducibility) were found to be satisfactory for three other TTX analogs (11-nor TTX-6-ol, 5-deoxy TTX, and 4,9-anhydro TTX). The method was found to be practical and suitable for use in regulatory testing, providing rapid turnaround of sample analysis. Plans currently underway on a full collaborative study to validate a HILIC-MS/MS method for paralytic shellfish poisoning toxins will be extended to include TTX in order to generate international acceptance, ultimately for use as an alternative official control testing method should regulatory controls be adopted.

Comparison of reverse transcription-quantitative polymerase chain reaction methods and platforms for single cell gene expression analysis.

Science.gov (United States)

Fox, Bridget C; Devonshire, Alison S; Baradez, Marc-Olivier; Marshall, Damian; Foy, Carole A

2012-08-15

Single cell gene expression analysis can provide insights into development and disease progression by profiling individual cellular responses as opposed to reporting the global average of a population. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) is the "gold standard" for the quantification of gene expression levels; however, the technical performance of kits and platforms aimed at single cell analysis has not been fully defined in terms of sensitivity and assay comparability. We compared three kits using purification columns (PicoPure) or direct lysis (CellsDirect and Cells-to-CT) combined with a one- or two-step RT-qPCR approach using dilutions of cells and RNA standards to the single cell level. Single cell-level messenger RNA (mRNA) analysis was possible using all three methods, although the precision, linearity, and effect of lysis buffer and cell background differed depending on the approach used. The impact of using a microfluidic qPCR platform versus a standard instrument was investigated for potential variability introduced by preamplification of template or scaling down of the qPCR to nanoliter volumes using laser-dissected single cell samples. The two approaches were found to be comparable. These studies show that accurate gene expression analysis is achievable at the single cell level and highlight the importance of well-validated experimental procedures for low-level mRNA analysis. Copyright © 2012 Elsevier Inc. All rights reserved.

The Value of Step-by-Step Risk Assessment for Unmanned Aircraft

DEFF Research Database (Denmark)

La Cour-Harbo, Anders

2018-01-01

The new European legislation expected in 2018 or 2019 will introduce a step-by-step process for conducting risk assessments for unmanned aircraft flight operations. This is a relatively simple approach to a very complex challenge. This work compares this step-by-step process to high fidelity risk...... modeling, and shows that at least for a series of example flight missions there is reasonable agreement between the two very different methods....

The Experiment Method for Manufacturing Grid Development on Single Computer

Institute of Scientific and Technical Information of China (English)

XIAO Youan; ZHOU Zude

2006-01-01

In this paper, an experiment method for the Manufacturing Grid application system development in the single personal computer environment is proposed. The characteristic of the proposed method is constructing a full prototype Manufacturing Grid application system which is hosted on a single personal computer with the virtual machine technology. Firstly, it builds all the Manufacturing Grid physical resource nodes on an abstraction layer of a single personal computer with the virtual machine technology. Secondly, all the virtual Manufacturing Grid resource nodes will be connected with virtual network and the application software will be deployed on each Manufacturing Grid nodes. Then, we can obtain a prototype Manufacturing Grid application system which is working in the single personal computer, and can carry on the experiment on this foundation. Compared with the known experiment methods for the Manufacturing Grid application system development, the proposed method has the advantages of the known methods, such as cost inexpensively, operation simple, and can get the confidence experiment result easily. The Manufacturing Grid application system constructed with the proposed method has the high scalability, stability and reliability. It is can be migrated to the real application environment rapidly.

Pyrosequencing™ : A one-step method for high resolution HLA typing

Directory of Open Access Journals (Sweden)

Marincola Francesco M

2003-11-01

Full Text Available Abstract While the use of high-resolution molecular typing in routine matching of human leukocyte antigens (HLA is expected to improve unrelated donor selection and transplant outcome, the genetic complexity of HLA still makes the current methodology limited and laborious. Pyrosequencing™ is a gel-free, sequencing-by-synthesis method. In a Pyrosequencing reaction, nucleotide incorporation proceeds sequentially along each DNA template at a given nucleotide dispensation order (NDO that is programmed into a pyrosequencer. Here we describe the design of a NDO that generates a pyrogram unique for any given allele or combination of alleles. We present examples of unique pyrograms generated from each of two heterozygous HLA templates, which would otherwise remain cis/trans ambiguous using standard sequencing based typing (SBT method. In addition, we display representative data that demonstrate long read and linear signal generation. These features are prerequisite of high-resolution typing and automated data analysis. In conclusion Pyrosequencing is a one-step method for high resolution DNA typing.

Thin film complementary metal oxide semiconductor (CMOS) device using a single-step deposition of the channel layer

KAUST Repository

Nayak, Pradipta K.

2014-04-14

We report, for the first time, the use of a single step deposition of semiconductor channel layer to simultaneously achieve both n-and p-type transport in transparent oxide thin film transistors (TFTs). This effect is achieved by controlling the concentration of hydroxyl groups (OH-groups) in the underlying gate dielectrics. The semiconducting tin oxide layer was deposited at room temperature, and the maximum device fabrication temperature was 350C. Both n and p-type TFTs showed fairly comparable performance. A functional CMOS inverter was fabricated using this novel scheme, indicating the potential use of our approach for various practical applications.

SALP, a new single-stranded DNA library preparation method especially useful for the high-throughput characterization of chromatin openness states.

Science.gov (United States)

Wu, Jian; Dai, Wei; Wu, Lin; Wang, Jinke

2018-02-13

Next-generation sequencing (NGS) is fundamental to the current biological and biomedical research. Construction of sequencing library is a key step of NGS. Therefore, various library construction methods have been explored. However, the current methods are still limited by some shortcomings. This study developed a new NGS library construction method, Single strand Adaptor Library Preparation (SALP), by using a novel single strand adaptor (SSA). SSA is a double-stranded oligonucleotide with a 3' overhang of 3 random nucleotides, which can be efficiently ligated to the 3' end of single strand DNA by T4 DNA ligase. SALP can be started with any denatured DNA fragments such as those sheared by Tn5 tagmentation, enzyme digestion and sonication. When started with Tn5-tagmented chromatin, SALP can overcome a key limitation of ATAC-seq and become a high-throughput NGS library construction method, SALP-seq, which can be used to comparatively characterize the chromatin openness state of multiple cells unbiasly. In this way, this study successfully characterized the comparative chromatin openness states of four different cell lines, including GM12878, HepG2, HeLa and 293T, with SALP-seq. Similarly, this study also successfully characterized the chromatin openness states of HepG2 cells with SALP-seq by using 10 5 to 500 cells. This study developed a new NGS library construction method, SALP, by using a novel kind of single strand adaptor (SSA), which should has wide applications in the future due to its unique performance.

Single step purification of recombinant proteins using the metal ion-inducible autocleavage (MIIA) domain as linker for tag removal.

Science.gov (United States)

Ibe, Susan; Schirrmeister, Jana; Zehner, Susanne

2015-08-20

For fast and easy purification, proteins are typically fused with an affinity tag, which often needs to be removed after purification. Here, we present a method for the removal of the affinity tag from the target protein in a single step protocol. The protein VIC_001052 of the coral pathogen Vibrio coralliilyticus ATCC BAA-450 contains a metal ion-inducible autocatalytic cleavage (MIIA) domain. Its coding sequence was inserted into an expression vector for the production of recombinant fusion proteins. Following, the target proteins MalE and mCherry were produced as MIIA-Strep fusion proteins in Escherichia coli. The target proteins could be separated from the MIIA-Strep part simply by the addition of calcium or manganese(II) ions within minutes. The cleavage is not affected in the pH range from 5.0 to 9.0 or at low temperatures (6°C). Autocleavage was also observed with immobilized protein on an affinity column. The protein yield was similar to that achieved with a conventional purification protocol. Copyright © 2015 Elsevier B.V. All rights reserved.

A Brief Introduction to Single-Molecule Fluorescence Methods.

Science.gov (United States)

van den Wildenberg, Siet M J L; Prevo, Bram; Peterman, Erwin J G

2018-01-01

One of the more popular single-molecule approaches in biological science is single-molecule fluorescence microscopy, which will be the subject of the following section of this volume. Fluorescence methods provide the sensitivity required to study biology on the single-molecule level, but they also allow access to useful measurable parameters on time and length scales relevant for the biomolecular world. Before several detailed experimental approaches will be addressed, we will first give a general overview of single-molecule fluorescence microscopy. We start with discussing the phenomenon of fluorescence in general and the history of single-molecule fluorescence microscopy. Next, we will review fluorescent probes in more detail and the equipment required to visualize them on the single-molecule level. We will end with a description of parameters measurable with such approaches, ranging from protein counting and tracking, single-molecule localization super-resolution microscopy, to distance measurements with Förster Resonance Energy Transfer and orientation measurements with fluorescence polarization.

Single-step preparation of selected biological fluids for the high performance liquid chromatographic analysis of fat-soluble vitamins and antioxidants.

Science.gov (United States)

Lazzarino, Giacomo; Longo, Salvatore; Amorini, Angela Maria; Di Pietro, Valentina; D'Urso, Serafina; Lazzarino, Giuseppe; Belli, Antonio; Tavazzi, Barbara

2017-12-08

Fat-soluble vitamins and antioxidants are of relevance in health and disease. Current methods to extract these compounds from biological fluids mainly need use of multi-steps and multi organic solvents. They are time-consuming and difficult to apply to treat simultaneously large sample number. We here describe a single-step, one solvent extraction of fat-soluble vitamins and antioxidants from biological fluids, and the chromatographic separation of all-trans-retinoic acid, 25-hydroxycholecalciferol, all-trans-retinol, astaxanthin, lutein, zeaxanthin, trans-β-apo-8'-carotenal, γ-tocopherol, β-cryptoxanthin, α-tocopherol, phylloquinone, lycopene, α-carotene, β-carotene and coenzyme Q 10 . Extraction is obtained by adding one volume of biological fluid to two acetonitrile volumes, vortexing for 60s and incubating for 60min at 37°C under agitation. HPLC separation occurs in 30min using Hypersil C18, 100×4.6mm, 5μm particle size column, gradient from 70% methanol+30% H 2 O to 100% acetonitrile, flow rate of 1.0ml/min and 37°C column temperature. Compounds are revealed using highly sensitive UV-VIS diode array detector. The HPLC method suitability was assessed in terms of sensitivity, reproducibility and recovery. Using the present extraction and chromatographic conditions we obtained values of the fat-soluble vitamins and antioxidants in serum from 50 healthy controls similar to those found in literature. Additionally, the profile of these compounds was also measured in seminal plasma from 20 healthy fertile donors. Results indicate that this simple, rapid and low cost sample processing is suitable to extract fat-soluble vitamins and antioxidants from biological fluids and can be applied in clinical and nutritional studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Method to make a single-step etch mask for 3D monolithic nanostructures

NARCIS (Netherlands)

Grishina, Diana; Harteveld, Cornelis A.M.; Woldering, L.A.; Vos, Willem L.

2015-01-01

Current nanostructure fabrication by etching is usually limited to planar structures as they are defined by a planar mask. The realization of three-dimensional (3D) nanostructures by etching requires technologies beyond planar masks. We present a method for fabricating a 3D mask that allows one to

Distributed Feedback Laser Based on Single Crystal Perovskite

Science.gov (United States)

Sun, Shang; Xiao, Shumin; Song, Qinghai

2017-06-01

We demonstrate a single crystal perovskite based, with grating-structured photoresist on top, highly polarized distributed feedback laser. A lower laser threshold than the Fabry-Perot mode lasers from the same single crystal CH3NH3PbBr3 microplate was obtained. Single crystal CH3NH3PbBr3 microplates was synthesized with one-step solution processed precipitation method. Once the photoresist on top of the microplate was patterned with electron beam, the device was realized. This one-step fabrication process utilized the advantage of single crystal to the greatest extend. The ultra-low defect density in single crystalline microplate offer an opportunity for lower threshold lasing action compare with poly-crystal perovskite films. In the experiment, the lasing action based on the distributed feedback grating design was found with lower threshold and higher intensity than the Fabry-Perot mode lasers supported by the flat facets of the same microplate.

Radiometric method for the determination of uranium in soil and air: single-laboratory evaluation and interlaboratory collaborative study

International Nuclear Information System (INIS)

Casella, V.R.; Bishop, C.T.; Glosby, A.A.

1980-02-01

Results of a single-laboratory evaluation and an interlaboratory collaborative study of a method for determining uranium isotopes in soil and air samples are presented. The method is applicable to 10-gram soil samples and to both glass fiber and polystyrene (Microsorban) air filter samples. Sample decomposition is accomplished with a nitric-hydrofluoric acid dissolution. After a solvent extraction step to remove most of the iron present, the uranium is isolated by anion exchange chromatography and electrodeposition. Alpha spectrometry is used to measure the uranium isotopes. Two soil samples, a glass fiber air filter sample, and a polystyrene air filter sample were used to evaluate the method for uranium concentrations ranging from a few tenths to about one hundred disintegrations per minute per sample. Tracer recoveries for the single-laboratory evaluation averaged 78%, while the tracer recoveries for the collaborative study averaged 66%. Although the precision of the collaborative study results did not approach counting statistics errors, the measured uranium concentrations for these samples agreed to within 5% of the reference concentrations when the uranium concentration was greater than one disintegration per minute per gram of soil or one disintegration per minute per air filter

Calibration of a single hexagonal NaI(Tl) detector using a new numerical method based on the efficiency transfer method

Energy Technology Data Exchange (ETDEWEB)

Abbas, Mahmoud I., E-mail: mabbas@physicist.net [Physics Department, Faculty of Science, Alexandria University, 21511 Alexandria (Egypt); Badawi, M.S. [Physics Department, Faculty of Science, Alexandria University, 21511 Alexandria (Egypt); Ruskov, I.N. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 1784 Sofia (Bulgaria); El-Khatib, A.M. [Physics Department, Faculty of Science, Alexandria University, 21511 Alexandria (Egypt); Grozdanov, D.N. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, 1784 Sofia (Bulgaria); Thabet, A.A. [Department of Medical Equipment Technology, Faculty of Allied Medical Sciences, Pharos University in Alexandria (Egypt); Kopatch, Yu.N. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Gouda, M.M. [Physics Department, Faculty of Science, Alexandria University, 21511 Alexandria (Egypt); Skoy, V.R. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

2015-01-21

Gamma-ray detector systems are important instruments in a broad range of science and new setup are continually developing. The most recent step in the evolution of detectors for nuclear spectroscopy is the construction of large arrays of detectors of different forms (for example, conical, pentagonal, hexagonal, etc.) and sizes, where the performance and the efficiency can be increased. In this work, a new direct numerical method (NAM), in an integral form and based on the efficiency transfer (ET) method, is used to calculate the full-energy peak efficiency of a single hexagonal NaI(Tl) detector. The algorithms and the calculations of the effective solid angle ratios for a point (isotropic irradiating) gamma-source situated coaxially at different distances from the detector front-end surface, taking into account the attenuation of the gamma-rays in the detector's material, end-cap and the other materials in-between the gamma-source and the detector, are considered as the core of this (ET) method. The calculated full-energy peak efficiency values by the (NAM) are found to be in a good agreement with the measured experimental data.

Optimization of One-Step In Situ Transesterification Method for Accurate Quantification of EPA in Nannochloropsis gaditana

Directory of Open Access Journals (Sweden)

Yuting Tang

2016-11-01

Full Text Available Microalgae are a valuable source of lipid feedstocks for biodiesel and valuable omega-3 fatty acids. Nannochloropsis gaditana has emerged as a promising producer of eicosapentaenoic acid (EPA due to its fast growth rate and high EPA content. In the present study, the fatty acid profile of Nannochloropsis gaditana was found to be naturally high in EPA and devoid of docosahexaenoic acid (DHA, thereby providing an opportunity to maximize the efficacy of EPA production. Using an optimized one-step in situ transesterification method (methanol:biomass = 90 mL/g; HCl 5% by vol.; 70 °C; 1.5 h, the maximum fatty acid methyl ester (FAME yield of Nannochloropsis gaditana cultivated under rich condition was quantified as 10.04% ± 0.08% by weight with EPA-yields as high as 4.02% ± 0.17% based on dry biomass. The total FAME and EPA yields were 1.58- and 1.23-fold higher separately than that obtained using conventional two-step method (solvent system: methanol and chloroform. This one-step in situ method provides a fast and simple method to measure fatty acid methyl ester (FAME yields and could serve as a promising method to generate eicosapentaenoic acid methyl ester from microalgae.

Imaginary Time Step Method to Solve the Dirac Equation with Nonlocal Potential

International Nuclear Information System (INIS)

Zhang Ying; Liang Haozhao; Meng Jie

2009-01-01

The imaginary time step (ITS) method is applied to solve the Dirac equation with nonlocal potentials in coordinate space. Taking the nucleus 12 C as an example, even with nonlocal potentials, the direct ITS evolution for the Dirac equation still meets the disaster of the Dirac sea. However, following the recipe in our former investigation, the disaster can be avoided by the ITS evolution for the corresponding Schroedinger-like equation without localization, which gives the convergent results exactly the same with those obtained iteratively by the shooting method with localized effective potentials.

Development and evaluation of one step single tube multiplex RT-PCR for rapid detection and typing of dengue viruses

OpenAIRE

Parida Manmohan; Shrivastava Ambuj; Santhosh SR; Dash Paban; Saxena Parag; Rao PV

2008-01-01

Abstract Background Dengue is emerging as a major public health concern in many parts of the world. The development of a one-step, single tube, rapid, and multiplex reverse transcription polymerase chain reaction (M-RT-PCR) for simultaneous detection and typing of dengue virus using serotype specific primers during acute phase of illness is reported. Results An optimal assay condition with zero background was established having no cross-reaction with closely related members of flavivirus (Jap...

Single step biotransformation of corn oil phytosterols to boldenone by a newly isolated Pseudomonas aeruginosa

Directory of Open Access Journals (Sweden)

Mohamed Eisa

2016-09-01

Full Text Available A new potent Pseudomonas aeruginosa isolate capable for biotransformation of corn oil phytosterol (PS to 4-androstene-3, 17-dione (AD, testosterone (T and boldenone (BOL was identified by phenotypic analysis and 16S rRNA gene sequencing. Sequential statistical strategy was used to optimize the biotransformation process mainly concerning BOL using Factorial design and response surface methodology (RSM. The production of BOL in single step microbial biotransformation from corn oil phytosterols by P. aeruginosa was not previously reported. Results showed that the pH concentration of the medium, (NH42SO4 and KH2PO4 were the most significant factors affecting BOL production. By analyzing the statistical model of three-dimensional surface plot, BOL production increased from 36.8% to 42.4% after the first step of optimization, and the overall biotransformation increased to 51.9%. After applying the second step of the sequential statistical strategy BOL production increased to 53.6%, and the overall biotransformation increased to 91.9% using the following optimized medium composition (g/l distilled water (NH42SO4, 2; KH2PO4, 4; Na2HPO4. 1; MgSO4·7H2O, 0.3; NaCl, 0.1; CaCl2·2H2O, 0.1; FeSO4·7H2O, 0.001; ammonium acetate 0.001; Tween 80, 0.05%; corn oil 0.5%; 8-hydroxyquinoline 0.016; pH 8; 200 rpm agitation speed and incubation time 36 h at 30 °C. Validation experiments proved the adequacy and accuracy of model, and the results showed the predicted value agreed well with the experimental values.

Single-reagent one-step procedures for the purification of ovine IgG, F(ab')2 and Fab antivenoms by caprylic acid.

Science.gov (United States)

Al-Abdulla, Ibrahim; Casewell, Nicholas R; Landon, John

2014-01-15

Antivenoms are typically produced in horses or sheep and often purified using salt precipitation of immunoglobulins or F(ab')2 fragments. Caprylic (octanoic) acid fractionation of antiserum has the advantage of not precipitating the desired antibodies, thereby avoiding potential degradation that can lead to the formation of aggregates, which may be the cause of some adverse reactions to antivenoms. Here we report that when optimising the purification of immunoglobulins from ovine antiserum raised against snake venom, caprylic acid was found to have no effect on the activity of the enzymes pepsin and papain, which are employed in antivenom manufacturing to digest immunoglobulins to obtain F(ab')2 and Fab fragments, respectively. A "single-reagent" method was developed for the production of F(ab')2 antivenom whereby whole ovine antiserum was mixed with both caprylic acid and pepsin and incubated for 4h at 37°C. For ovine Fab antivenom production from whole antiserum, the "single reagent" comprised of caprylic acid, papain and l-cysteine; after incubation at 37°C for 18-20h, iodoacetamide was added to stop the reaction. Caprylic acid facilitated the precipitation of albumin, resulting in a reduced protein load presented to the digestion enzymes, culminating in substantial reductions in processing time. The ovine IgG, F(ab')2 and Fab products obtained using these novel caprylic acid methods were comparable in terms of yield, purity and specific activity to those obtained by multi-step conventional salt fractionation with sodium sulphate. Copyright © 2013 Elsevier B.V. All rights reserved.

Isotopically pure single crystal epitaxial diamond films and their preparation

International Nuclear Information System (INIS)

Banholzer, W.F.; Anthony, T.R.; Williams, D.M.

1992-01-01

The present invention is directed to the production of single crystal diamond consisting of isotopically pure carbon-12 or carbon-13. In the present invention, isotopically pure single crystal diamond is grown on a single crystal substrate directly from isotopically pure carbon-12 or carbon-13. One method for forming isotopically pure single crystal diamond comprises the steps of placing in a reaction chamber a single substrate heated to an elevated diamond forming temperature. Another method for forming isotopically pure single crystal diamond comprises diffusing isotopically pure carbon-12 or carbon-13 through a metallic catalyst under high pressure to a region containing a single crystal substrate to form an isotopically pure single crystal diamond layer on said single crystal substrate

Accelerated solvent extraction method with one-step clean-up for hydrocarbons in soil

International Nuclear Information System (INIS)

Nurul Huda Mamat Ghani; Norashikin Sain; Rozita Osman; Zuraidah Abdullah Munir

2007-01-01

The application of accelerated solvent extraction (ASE) using hexane combined with neutral silica gel and sulfuric acid/ silica gel (SA/ SG) to remove impurities prior to analysis by gas chromatograph with flame ionization detector (GC-FID) was studied. The efficiency of extraction was evaluated based on the three hydrocarbons; dodecane, tetradecane and pentadecane spiked to soil sample. The effect of ASE operating conditions (extraction temperature, extraction pressure, static time) was evaluated and the optimized condition obtained from the study was extraction temperature of 160 degree Celsius, extraction pressure of 2000 psi with 5 minutes static extraction time. The developed ASE with one-step clean-up method was applied in the extraction of hydrocarbons from spiked soil and the amount extracted was comparable to ASE extraction without clean-up step with the advantage of obtaining cleaner extract with reduced interferences. Therefore in the developed method, extraction and clean-up for hydrocarbons in soil can be achieved rapidly and efficiently with reduced solvent usage. (author)

A three operator split-step method covering a larger set of non-linear partial differential equations

Science.gov (United States)

Zia, Haider

2017-06-01

This paper describes an updated exponential Fourier based split-step method that can be applied to a greater class of partial differential equations than previous methods would allow. These equations arise in physics and engineering, a notable example being the generalized derivative non-linear Schrödinger equation that arises in non-linear optics with self-steepening terms. These differential equations feature terms that were previously inaccessible to model accurately with low computational resources. The new method maintains a 3rd order error even with these additional terms and models the equation in all three spatial dimensions and time. The class of non-linear differential equations that this method applies to is shown. The method is fully derived and implementation of the method in the split-step architecture is shown. This paper lays the mathematical ground work for an upcoming paper employing this method in white-light generation simulations in bulk material.

Changes in step-width during dual-task walking predicts falls.

Science.gov (United States)

Nordin, E; Moe-Nilssen, R; Ramnemark, A; Lundin-Olsson, L

2010-05-01

The aim was to evaluate whether gait pattern changes between single- and dual-task conditions were associated with risk of falling in older people. Dual-task cost (DTC) of 230 community living, physically independent people, 75 years or older, was determined with an electronic walkway. Participants were followed up each month for 1 year to record falls. Mean and variability measures of gait characteristics for 5 dual-task conditions were compared to single-task walking for each participant. Almost half (48%) of the participants fell at least once during follow-up. Risk of falling increased in individuals where DTC for performing a subtraction task demonstrated change in mean step-width compared to single-task walking. Risk of falling decreased in individuals where DTC for carrying a cup and saucer demonstrated change compared to single-task walking in mean step-width, mean step-time, and step-length variability. Degree of change in gait characteristics related to a change in risk of falling differed between measures. Prognostic guidance for fall risk was found for the above DTCs in mean step-width with a negative likelihood ratio of 0.5 and a positive likelihood ratio of 2.3, respectively. Findings suggest that changes in step-width, step-time, and step-length with dual tasking may be related to future risk of falling. Depending on the nature of the second task, DTC may indicate either an increased risk of falling, or a protective strategy to avoid falling. Copyright 2010. Published by Elsevier B.V.

GOTHIC: Gravitational oct-tree code accelerated by hierarchical time step controlling

Science.gov (United States)

Miki, Yohei; Umemura, Masayuki

2017-04-01

The tree method is a widely implemented algorithm for collisionless N-body simulations in astrophysics well suited for GPU(s). Adopting hierarchical time stepping can accelerate N-body simulations; however, it is infrequently implemented and its potential remains untested in GPU implementations. We have developed a Gravitational Oct-Tree code accelerated by HIerarchical time step Controlling named GOTHIC, which adopts both the tree method and the hierarchical time step. The code adopts some adaptive optimizations by monitoring the execution time of each function on-the-fly and minimizes the time-to-solution by balancing the measured time of multiple functions. Results of performance measurements with realistic particle distribution performed on NVIDIA Tesla M2090, K20X, and GeForce GTX TITAN X, which are representative GPUs of the Fermi, Kepler, and Maxwell generation of GPUs, show that the hierarchical time step achieves a speedup by a factor of around 3-5 times compared to the shared time step. The measured elapsed time per step of GOTHIC is 0.30 s or 0.44 s on GTX TITAN X when the particle distribution represents the Andromeda galaxy or the NFW sphere, respectively, with 224 = 16,777,216 particles. The averaged performance of the code corresponds to 10-30% of the theoretical single precision peak performance of the GPU.

Demonstration of Single-Barium-Ion Sensitivity for Neutrinoless Double-Beta Decay Using Single-Molecule Fluorescence Imaging

Energy Technology Data Exchange (ETDEWEB)

McDonald, A. D.; Jones, B. J. P.; Nygren, D. R.; Adams, C.; Álvarez, V.; Azevedo, C. D. R.; Benlloch-Rodríguez, J. M.; Borges, F. I. G. M.; Botas, A.; Cárcel, S.; Carrión, J. V.; Cebrián, S.; Conde, C. A. N.; Díaz, J.; Diesburg, M.; Escada, J.; Esteve, R.; Felkai, R.; Fernandes, L. M. P.; Ferrario, P.; Ferreira, A. L.; Freitas, E. D. C.; Goldschmidt, A.; Gómez-Cadenas, J. J.; González-Díaz, D.; Gutiérrez, R. M.; Guenette, R.; Hafidi, K.; Hauptman, J.; Henriques, C. A. O.; Hernandez, A. I.; Hernando Morata, J. A.; Herrero, V.; Johnston, S.; Labarga, L.; Laing, A.; Lebrun, P.; Liubarsky, I.; López-March, N.; Losada, M.; Martín-Albo, J.; Martínez-Lema, G.; Martínez, A.; Monrabal, F.; Monteiro, C. M. B.; Mora, F. J.; Moutinho, L. M.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Para, A.; Pérez, J.; Querol, M.; Repond, J.; Renner, J.; Riordan, S.; Ripoll, L.; Rodríguez, J.; Rogers, L.; Santos, F. P.; dos Santos, J. M. F.; Simón, A.; Sofka, C.; Sorel, M.; Stiegler, T.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F. C. A.; Webb, R.; White, J. T.; Yahlali, N.

2018-03-01

A new method to tag the barium daughter in the double beta decay of $^{136}$Xe is reported. Using the technique of single molecule fluorescent imaging (SMFI), individual barium dication (Ba$^{++}$) resolution at a transparent scanning surface has been demonstrated. A single-step photo-bleach confirms the single ion interpretation. Individual ions are localized with super-resolution ($\\sim$2~nm), and detected with a statistical significance of 12.9~$\\sigma$ over backgrounds. This lays the foundation for a new and potentially background-free neutrinoless double beta decay technology, based on SMFI coupled to high pressure xenon gas time projection chambers.

Demonstration of Single-Barium-Ion Sensitivity for Neutrinoless Double-Beta Decay Using Single-Molecule Fluorescence Imaging

Science.gov (United States)

McDonald, A. D.; Jones, B. J. P.; Nygren, D. R.; Adams, C.; Álvarez, V.; Azevedo, C. D. R.; Benlloch-Rodríguez, J. M.; Borges, F. I. G. M.; Botas, A.; Cárcel, S.; Carrión, J. V.; Cebrián, S.; Conde, C. A. N.; Díaz, J.; Diesburg, M.; Escada, J.; Esteve, R.; Felkai, R.; Fernandes, L. M. P.; Ferrario, P.; Ferreira, A. L.; Freitas, E. D. C.; Goldschmidt, A.; Gómez-Cadenas, J. J.; González-Díaz, D.; Gutiérrez, R. M.; Guenette, R.; Hafidi, K.; Hauptman, J.; Henriques, C. A. O.; Hernandez, A. I.; Hernando Morata, J. A.; Herrero, V.; Johnston, S.; Labarga, L.; Laing, A.; Lebrun, P.; Liubarsky, I.; López-March, N.; Losada, M.; Martín-Albo, J.; Martínez-Lema, G.; Martínez, A.; Monrabal, F.; Monteiro, C. M. B.; Mora, F. J.; Moutinho, L. M.; Muñoz Vidal, J.; Musti, M.; Nebot-Guinot, M.; Novella, P.; Palmeiro, B.; Para, A.; Pérez, J.; Querol, M.; Repond, J.; Renner, J.; Riordan, S.; Ripoll, L.; Rodríguez, J.; Rogers, L.; Santos, F. P.; dos Santos, J. M. F.; Simón, A.; Sofka, C.; Sorel, M.; Stiegler, T.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F. C. A.; Webb, R.; White, J. T.; Yahlali, N.; NEXT Collaboration

2018-03-01

A new method to tag the barium daughter in the double-beta decay of Xe 136 is reported. Using the technique of single molecule fluorescent imaging (SMFI), individual barium dication (Ba++ ) resolution at a transparent scanning surface is demonstrated. A single-step photobleach confirms the single ion interpretation. Individual ions are localized with superresolution (˜2 nm ), and detected with a statistical significance of 12.9 σ over backgrounds. This lays the foundation for a new and potentially background-free neutrinoless double-beta decay technology, based on SMFI coupled to high pressure xenon gas time projection chambers.

Promotion of the oxidation of carbon monoxide at stepped platinum single-crystal electrodes in alkaline media by lithium and beryllium cations.

Science.gov (United States)

Stoffelsma, Chantal; Rodriguez, Paramaconi; Garcia, Gonzalo; Garcia-Araez, Nuria; Strmcnik, Dusan; Marković, Nenad M; Koper, Marc T M

2010-11-17

The role of alkali cations (Li(+), Na(+), K(+), Cs(+), and Be(2+)) on the blank voltammetric response and the oxidative stripping of carbon monoxide from stepped Pt single-crystal electrodes in alkaline media has been investigated by cyclic voltammetry. A strong influence of the nature of the cation on both the blank voltammetric profile and the CO oxidation is observed and related to the influence of the cation on the specific adsorption of OH on the platinum surface. Especially Li(+) and Be(2+) cations markedly affect the adsorption of OH and thereby have a significant promoting effect on CO(ads) oxidation. The voltammetric experiments suggest that, on Pt(111), the influence of Li(+) (and Be(2+)) is primarily through a weakening of the repulsive interactions between the OH in the OH adlayer, whereas in the presence of steps also, the onset of OH adsorption is at a lower potential, both on steps and on terraces.

Optimizing the calculation of DM,CO and VC via the single breath single oxygen tension DLCO/NO method.

Science.gov (United States)

Coffman, Kirsten E; Taylor, Bryan J; Carlson, Alex R; Wentz, Robert J; Johnson, Bruce D

2016-01-15

Alveolar-capillary membrane conductance (D(M,CO)) and pulmonary-capillary blood volume (V(C)) are calculated via lung diffusing capacity for carbon monoxide (DL(CO)) and nitric oxide (DL(NO)) using the single breath, single oxygen tension (single-FiO2) method. However, two calculation parameters, the reaction rate of carbon monoxide with blood (θ(CO)) and the D(M,NO)/D(M,CO) ratio (α-ratio), are controversial. This study systematically determined optimal θ(CO) and α-ratio values to be used in the single-FiO2 method that yielded the most similar D(M,CO) and V(C) values compared to the 'gold-standard' multiple-FiO2 method. Eleven healthy subjects performed single breath DL(CO)/DL(NO) maneuvers at rest and during exercise. D(M,CO) and V(C) were calculated via the single-FiO2 and multiple-FiO2 methods by implementing seven θ(CO) equations and a range of previously reported α-ratios. The RP θ(CO) equation (Reeves, R.B., Park, H.K., 1992. Respiration Physiology 88 1-21) and an α-ratio of 4.0-4.4 yielded DM,CO and VC values that were most similar between methods. The RP θ(CO) equation and an experimental α-ratio should be used in future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Modified random hinge transport mechanics and multiple scattering step-size selection in EGS5

International Nuclear Information System (INIS)

Wilderman, S.J.; Bielajew, A.F.

2005-01-01

The new transport mechanics in EGS5 allows for significantly longer electron transport step sizes and hence shorter computation times than required for identical problems in EGS4. But as with all Monte Carlo electron transport algorithms, certain classes of problems exhibit step-size dependencies even when operating within recommended ranges, sometimes making selection of step-sizes a daunting task for novice users. Further contributing to this problem, because of the decoupling of multiple scattering and continuous energy loss in the dual random hinge transport mechanics of EGS5, there are two independent step sizes in EGS5, one for multiple scattering and one for continuous energy loss, each of which influences speed and accuracy in a different manner. Further, whereas EGS4 used a single value of fractional energy loss (ESTEPE) to determine step sizes at all energies, to increase performance by decreasing the amount of effort expended simulating lower energy particles, EGS5 permits the fractional energy loss values which are used to determine both the multiple scattering and continuous energy loss step sizes to vary with energy. This results in requiring the user to specify four fractional energy loss values when optimizing computations for speed. Thus, in order to simplify step-size selection and to mitigate step-size dependencies, a method has been devised to automatically optimize step-size selection based on a single material dependent input related to the size of problem tally region. In this paper we discuss the new transport mechanics in EGS5 and describe the automatic step-size optimization algorithm. (author)

Development of a three dimensional circulation model based on fractional step method

Directory of Open Access Journals (Sweden)

Mazen Abualtayef

2010-03-01

Full Text Available A numerical model was developed for simulating a three-dimensional multilayer hydrodynamic and thermodynamic model in domains with irregular bottom topography. The model was designed for examining the interactions between flow and topography. The model was based on the three-dimensional Navier-Stokes equations and was solved using the fractional step method, which combines the finite difference method in the horizontal plane and the finite element method in the vertical plane. The numerical techniques were described and the model test and application were presented. For the model application to the northern part of Ariake Sea, the hydrodynamic and thermodynamic results were predicted. The numerically predicted amplitudes and phase angles were well consistent with the field observations.

Single beam pass migmacell method and apparatus

International Nuclear Information System (INIS)

Maglich, B.C.; Nering, J.E.; Mazarakis, M.G.; Miller, R.A.

1976-01-01

The invention provides improvements in migmacell apparatus and method by dispensing with the need for metastable confinement of injected molecular ions for multiple precession periods. Injected molecular ions undergo a 'single pass' through the reaction volume. By preconditioning the injected beam such that it contains a population distribution of molecules in higher vibrational states than in the case of a normal distribution, injected molecules in the single pass exper-ience collisionless dissociation in the migmacell under magnetic influence, i.e., so-called Lorentz dissociation. Dissociationions then form atomic migma

Acomparative Study Comparing Low-dose Step-up Versus Step-down in Polycystic Ovary Syndrome Resistant to Clomiphene

Directory of Open Access Journals (Sweden)

S Peivandi

2010-03-01

Full Text Available Introduction: Polycystic ovary syndrome(PCOS is one of the most common cause of infertility in women. clomiphene is the first line of treatment. however 20% of patients are resistant to clomiphene. because of follicular hypersensitivity to gonadotropins in pcod, multiple follicular growth and development occurs which is cause of OHSS and multiple pregnancy. Our aim of this random and clinical study was comparation between step-down and low dose step-up methods for induction ovulation in clomiphene resistant. Methods: 60 cases were included 30 women in low-dose step-up group and 30 women in step-down group. In low-dose step-up HMG 75u/d and in step-down HMG 225u/d was started on 3th days of cycle, monitoring with vaginal sonography was done on 8th days of cycle. When follicle with>14 mm in diameter was seen HMG dose was continued in low-dose step-up and was decreased in step-down group. When follicle reached to 18mm in diameter, amp HCG 10000 unit was injected and IUI was performed 36 hours later. Results: Number of HMG ampules, number of follicles> 14mm on the day of HCG injection and level of serum estradiol was greater in low dose step up protocol than step down protocol(p<0/0001. Ovulation rate and pregnancy rate was greater in lowdose step up group than step down group with significant difference (p<0/0001. Conclusion: Our study showed that low-dose step-up regimen with HMG is effective for stimulating ovulation and clinical pregnancy but in view of monofollicular growth, the step down method was more effective and safe. In our study multifolliular growth in step-up method was higher than step-down method. We can predict possibility of Ovarian Hyperstimulation Syndrome syndrome in highly sensitive PCOS patients.

Influence of the drying method in chitosans purification step

International Nuclear Information System (INIS)

Fonseca, Ana C.M.; Batista, Jorge G.S.; Bettega, Antonio; Lima, Nelson B. de

2015-01-01

Currently, the study of extracellular biopolymers properties has received prominence for being easy extraction and purification. Chitosan has been an attractive proposition for applications in various fields such as engineering, biotechnology, medicine and pharmacology. For such applications, it is necessary purification of chitosan to obtain a product more concentrated and free of undesirable impurities. However, at this stage of the process of obtaining the biopolymer may occur morphological and physicochemical changes. This study evaluated the influence of the drying process after purification of a commercial chitosan sample and the importance of this step and its cost/benefit in applications requiring a high degree of purity. The method of drying influenced in the organoleptic properties and in the main characteristics of material. Analysis of the crystal structure by X-ray diffraction showed that the degree of crystallinity, X (%), in the purified chitosan samples was lower when compared with the unpurified sample. The degree of acetylation, DA (%), was analyzed by spectroscopy infrared with no significant changes on the three drying methods assessed, unlike the viscosimetric molecular weight, M_v, determined by capillary viscometry. (author)

Influence of application methods of one-step self-etching adhesives on microtensile bond strength

OpenAIRE

Chul-Kyu Choi,; Sung-Ae Son; Jin-Hee Ha; Bock Hur; Hyeon-Cheol Kim; Yong-Hun Kwon; Jeong-Kil Park

2011-01-01

Objectives The purpose of this study was to evaluate the effect of various application methods of one-step self-etch adhesives to microtensile resin-dentin bond strength. Materials and Methods Thirty-six extracted human molars were used. The teeth were assigned randomly to twelve groups (n = 15), according to the three different adhesive systems (Clearfil Tri-S Bond, Adper Prompt L-Pop, G-Bond) and application methods. The adhesive systems were applied on the dentin as follows: 1) T...

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

International Nuclear Information System (INIS)

Wright, Norrie

1989-01-01

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

Electron diffraction of CBr{sub 4} in superfluid helium droplets: A step towards single molecule diffraction

Energy Technology Data Exchange (ETDEWEB)

He, Yunteng; Zhang, Jie; Kong, Wei, E-mail: wei.kong@oregonstate.edu [Department of Chemistry, Oregon State University, Corvallis, Oregon 97331-4003 (United States)

2016-07-21

We demonstrate the practicality of electron diffraction of single molecules inside superfluid helium droplets using CBr{sub 4} as a testing case. By reducing the background from pure undoped droplets via multiple doping, with small corrections for dimers and trimers, clearly resolved diffraction rings of CBr{sub 4} similar to those of gas phase molecules can be observed. The experimental data from CBr{sub 4} doped droplets are in agreement with both theoretical calculations and with experimental results of gaseous species. The abundance of monomers and clusters in the droplet beam also qualitatively agrees with the Poisson statistics. Possible extensions of this approach to macromolecular ions will also be discussed. This result marks the first step in building a molecular goniometer using superfluid helium droplet cooling and field induced orientation. The superior cooling effect of helium droplets is ideal for field induced orientation, but the diffraction background from helium is a concern. This work addresses this background issue and identifies a possible solution. Accumulation of diffraction images only becomes meaningful when all images are produced from molecules oriented in the same direction, and hence a molecular goniometer is a crucial technology for serial diffraction of single molecules.

Comparison of step-by-step kinematics of resisted, assisted and unloaded 20-m sprint runs.

Science.gov (United States)

van den Tillaar, Roland; Gamble, Paul

2018-03-26

This investigation examined step-by-step kinematics of sprint running acceleration. Using a randomised counterbalanced approach, 37 female team handball players (age 17.8 ± 1.6 years, body mass 69.6 ± 9.1 kg, height 1.74 ± 0.06 m) performed resisted, assisted and unloaded 20-m sprints within a single session. 20-m sprint times and step velocity, as well as step length, step frequency, contact and flight times of each step were evaluated for each condition with a laser gun and an infrared mat. Almost all measured parameters were altered for each step under the resisted and assisted sprint conditions (η 2  ≥ 0.28). The exception was step frequency, which did not differ between assisted and normal sprints. Contact time, flight time and step frequency at almost each step were different between 'fast' vs. 'slow' sub-groups (η 2  ≥ 0.22). Nevertheless overall both groups responded similarly to the respective sprint conditions. No significant differences in step length were observed between groups for the respective condition. It is possible that continued exposure to assisted sprinting might allow the female team-sports players studied to adapt their coordination to the 'over-speed' condition and increase step frequency. It is notable that step-by-step kinematics in these sprints were easy to obtain using relatively inexpensive equipment with possibilities of direct feedback.

Radiation grafting of pH-sensitive acrylic acid and 4-vinyl pyridine onto nylon-6 using one- and two-step methods

International Nuclear Information System (INIS)

Ortega, Alejandra; Alarcón, Darío; Muñoz-Muñoz, Franklin; Garzón-Fontecha, Angélica; Burillo, Guillermina

2015-01-01

Acrylic acid (AAc) and 4-vinyl pyridine (4VP) were γ-ray grafted onto nylon-6 (Ny 6 ) films via pre-irradiation oxidative method. These monomers were grafted using a one-step method to render Ny 6 -g–(AAc/4VP). A two-step or sequential method was used to render (Ny 6 -g–AAc)-g–4VP. Random copolymer branches were obtained when the grafting was carried out via one-step method using the two monomers together. The two-step method was applied to graft chains of 4VP on both Ny 6 substrate and previously grafted AAc chains (Ny 6 -g–AAc). The two types of binary copolymers synthesized were characterized to determine the amount of grafted polymers, the thermal behavior (DSC and TGA), the surface composition (XPS), and the pH responsiveness. In the two-step process, it is possible to achieve a higher graft yield, better control of the amount of each monomer, good reversibility in the swelling/deswelling process and shorter time to achieve equilibrium swelling. - Highlights: • A new binary graft of 4VP and AAc onto Ny 6 films was synthesized by γ-radiation. • The binary grafted material has potential application for heavy ion retention. • The two-step method shows better conditions in swelling and reversibility properties. • Surface distribution of monomers was evaluate by XPS characterization

Canine distemper virus detection by different methods of One-Step RT-qPCR

Directory of Open Access Journals (Sweden)

Claudia de Camargo Tozato

2016-01-01

Full Text Available ABSTRACT: Three commercial kits of One-Step RT-qPCR were evaluated for the molecular diagnosis of Canine Distemper Virus. Using the kit that showed better performance, two systems of Real-time RT-PCR (RT-qPCR assays were tested and compared for analytical sensitivity to Canine Distemper Virus RNA detection: a One-Step RT-qPCR (system A and a One-Step RT-qPCR combined with NESTED-qPCR (system B. Limits of detection for both systems were determined using a serial dilution of Canine Distemper Virus synthetic RNA or a positive urine sample. In addition, the same urine sample was tested using samples with prior centrifugation or ultracentrifugation. Commercial kits of One-Step RT-qPCR assays detected canine distemper virus RNA in 10 (100% urine samples from symptomatic animals tested. The One-Step RT-qPCR kit that showed better results was used to evaluate the analytical sensitivity of the A and B systems. Limit of detection using synthetic RNA for the system A was 11 RNA copies µL-1 and 110 RNA copies µl-1 for first round System B. The second round of the NESTED-qPCR for System B had a limit of detection of 11 copies µl-1. Relationship between Ct values and RNA concentration was linear. The RNA extracted from the urine dilutions was detected in dilutions of 10-3 and10-2 by System A and B respectively. Urine centrifugation increased the analytical sensitivity of the test and proved to be useful for routine diagnostics. The One-Step RT-qPCR is a fast, sensitive and specific method for canine distemper routine diagnosis and research projects that require sensitive and quantitative methodology.

Three-step interferometric method with blind phase shifts by use of interframe correlation between interferograms

Science.gov (United States)

Muravsky, Leonid I.; Kmet', Arkady B.; Stasyshyn, Ihor V.; Voronyak, Taras I.; Bobitski, Yaroslav V.

2018-06-01

A new three-step interferometric method with blind phase shifts to retrieve phase maps (PMs) of smooth and low-roughness engineering surfaces is proposed. Evaluating of two unknown phase shifts is fulfilled by using the interframe correlation between interferograms. The method consists of two stages. The first stage provides recording of three interferograms of a test object and their processing including calculation of unknown phase shifts, and retrieval of a coarse PM. The second stage implements firstly separation of high-frequency and low-frequency PMs and secondly producing of a fine PM consisting of areal surface roughness and waviness PMs. Extraction of the areal surface roughness and waviness PMs is fulfilled by using a linear low-pass filter. The computer simulation and experiments fulfilled to retrieve a gauge block surface area and its areal surface roughness and waviness have confirmed the reliability of the proposed three-step method.

Effect of One-Step and Multi-Steps Polishing System on Enamel Roughness

Directory of Open Access Journals (Sweden)

Cynthia Sumali

2013-07-01

Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 The final procedures of orthodontic treatment are bracket debonding and cleaning the remaining adhesive. Multi-step polishing system is the most common method used. The disadvantage of that system is long working time, because of the stages that should be done. Therefore, dental material manufacturer make an improvement to the system, to reduce several stages into one stage only. This new system is known as one-step polishing system. Objective: To compare the effect of one-step and multi-step polishing system on enamel roughness after orthodontic bracket debonding. Methods: Randomized control trial was conducted included twenty-eight maxillary premolar randomized into two polishing system; one-step OptraPol (Ivoclar, Vivadent and multi-step AstroPol (Ivoclar, Vivadent. After bracket debonding, the remaining adhesive on each group was cleaned by subjective polishing system for ninety seconds using low speed handpiece. The enamel roughness was subjected to profilometer, registering two roughness parameters (Ra, Rz. Independent t-test was used to analyze the mean score of enamel roughness in each group. Results: There was no significant difference of enamel roughness between one-step and multi-step polishing system (p>0.005. Conclusion: One-step polishing system can produce a similar enamel roughness to multi-step polishing system after bracket debonding and adhesive cleaning.DOI: 10.14693/jdi.v19i3.136

Longitudinal coupling impedance of step discontinuities in a circular beam tube

International Nuclear Information System (INIS)

Hahn, H.; Zatz, S.

1979-01-01

The longitudinal coupling impedance presented by a single wall discontinuity to the circulating beam in a circular accelerator or storage ring is usually analyzed by considering a developed periodic structure. However, the typical parameters are often such that it becomes adequate to treat the discontinuity as a nonperiodic problem. Using modal field matching methods, solutions were derived for the cases of a single as well as a double-step discontinuity in a circular beam tube. Numerical results are presented in this paper and the typical behavior at low frequency, at reasonance, and above cut-off is discussed

Validation of single-sample doubly labeled water method

International Nuclear Information System (INIS)

Webster, M.D.; Weathers, W.W.

1989-01-01

We have experimentally validated a single-sample variant of the doubly labeled water method for measuring metabolic rate and water turnover in a very small passerine bird, the verdin (Auriparus flaviceps). We measured CO 2 production using the Haldane gravimetric technique and compared these values with estimates derived from isotopic data. Doubly labeled water results based on the one-sample calculations differed from Haldane values by less than 0.5% on average (range -8.3 to 11.2%, n = 9). Water flux computed by the single-sample method differed by -1.5% on average from results for the same birds based on the standard, two-sample technique (range -13.7 to 2.0%, n = 9)

Single-Step Fabrication Using a Phase Inversion Method of Poly(vinylidene fluoride) (PVDF) Activated Carbon Air Cathodes for Microbial Fuel Cells

KAUST Repository

Yang, Wulin

2014-10-14

Air cathodes used in microbial fuel cells (MFCs) need to have high catalytic activity for oxygen reduction, but they must also be easy to manufacture, inexpensive, and watertight. A simple one-step, phase inversion process was used here to construct an inexpensive MFC cathode using a poly(vinylidene fluoride) (PVDF) binder and an activated carbon catalyst. The phase inversion process enabled cathode preparation at room temperatures, without the need for additional heat treatment, and it produced for the first time a cathode that did not require a separate diffusion layer to prevent water leakage. MFCs using this new type of cathode produced a maximum power density of 1470 ± 50 mW m–2 with acetate as a substrate, and 230 ± 10 mW m–2 with domestic wastewater. These power densities were similar to those obtained using cathodes made using more expensive materials or more complex procedures, such as cathodes with a polytetrafluoroethylene (PTFE) binder and a poly(dimethylsiloxane) (PDMS) diffusion layer, or a Pt catalyst. Even though the PVDF cathodes did not have a diffusion layer, they withstood up to 1.22 ± 0.04 m of water head (∼12 kPa) without leakage, compared to 0.18 ± 0.02 m for cathodes made using PTFE binder and PDMS diffusion layer. The cost of PVDF and activated carbon ($3 m–2) was less than that of the stainless steel mesh current collector ($12 m–2). PVDF-based AC cathodes therefore are inexpensive, have excellent performance in terms of power and water leakage, and they can be easily manufactured using a single phase inversion process at room temperature.

Sharp Penalty Term and Time Step Bounds for the Interior Penalty Discontinuous Galerkin Method for Linear Hyperbolic Problems

NARCIS (Netherlands)

Geevers, Sjoerd; van der Vegt, J.J.W.

2017-01-01

We present sharp and sucient bounds for the interior penalty term and time step size to ensure stability of the symmetric interior penalty discontinuous Galerkin (SIPDG) method combined with an explicit time-stepping scheme. These conditions hold for generic meshes, including unstructured

A new method of preparing single-walled carbon nanotubes

Indian Academy of Sciences (India)

A novel method of purification for single-walled carbon nanotubes, prepared by an arc-discharge method, is described. The method involves a combination of acid washing followed by high temperature hydrogen treatment to remove the metal nanoparticles and amorphous carbon present in the as-synthesized singlewalled ...

A Novel Motion Compensation Method for Random Stepped Frequency Radar with M-sequence

Science.gov (United States)

Liao, Zhikun; Hu, Jiemin; Lu, Dawei; Zhang, Jun

2018-01-01

The random stepped frequency radar is a new kind of synthetic wideband radar. In the research, it has been found that it possesses a thumbtack-like ambiguity function which is considered to be the ideal one. This also means that only a precise motion compensation could result in the correct high resolution range profile. In this paper, we will introduce the random stepped frequency radar coded by M-sequence firstly and briefly analyse the effect of relative motion between target and radar on the distance imaging, which is called defocusing problem. Then, a novel motion compensation method, named complementary code cancellation, will be put forward to solve this problem. Finally, the simulated experiments will demonstrate its validity and the computational analysis will show up its efficiency.

Large-area gold nanohole arrays fabricated by one-step method for surface plasmon resonance biochemical sensing.

Science.gov (United States)

Qi, Huijie; Niu, Lihong; Zhang, Jie; Chen, Jian; Wang, Shujie; Yang, Jingjing; Guo, Siyi; Lawson, Tom; Shi, Bingyang; Song, Chunpeng

2018-04-01

Surface plasmon resonance (SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale arrays is essential for the development of SPR nanosensors. In this work, we report a one-step method to fabricate nanohole arrays by thermal nanoimprinting in the matrix of IPS (Intermediate Polymer Stamp). No additional etching process or supporting substrate is required. The preparation process is simple, time-saving and compatible for roll-to-roll process, potentially allowing mass production. Moreover, the nanohole arrays were integrated into detection platform as SPR sensors to investigate different types of biological binding interactions. The results demonstrate that our one-step method can be used to efficiently fabricate large-area and uniform nanohole arrays for biochemical sensing.

Methods for Gas Sensing with Single-Walled Carbon Nanotubes

Science.gov (United States)

Kaul, Anupama B. (Inventor)

2013-01-01

Methods for gas sensing with single-walled carbon nanotubes are described. The methods comprise biasing at least one carbon nanotube and exposing to a gas environment to detect variation in temperature as an electrical response.

On the limitations of fixed-step-size adaptive methods with response confidence.

Science.gov (United States)

Hsu, Yung-Fong; Chin, Ching-Lan

2014-05-01

The family of (non-parametric, fixed-step-size) adaptive methods, also known as 'up-down' or 'staircase' methods, has been used extensively in psychophysical studies for threshold estimation. Extensions of adaptive methods to non-binary responses have also been proposed. An example is the three-category weighted up-down (WUD) method (Kaernbach, 2001) and its four-category extension (Klein, 2001). Such an extension, however, is somewhat restricted, and in this paper we discuss its limitations. To facilitate the discussion, we characterize the extension of WUD by an algorithm that incorporates response confidence into a family of adaptive methods. This algorithm can also be applied to two other adaptive methods, namely Derman's up-down method and the biased-coin design, which are suitable for estimating any threshold quantiles. We then discuss via simulations of the above three methods the limitations of the algorithm. To illustrate, we conduct a small scale of experiment using the extended WUD under different response confidence formats to evaluate the consistency of threshold estimation. © 2013 The British Psychological Society.

A single model procedure for tank calibration function estimation

International Nuclear Information System (INIS)

York, J.C.; Liebetrau, A.M.

1995-01-01

Reliable tank calibrations are a vital component of any measurement control and accountability program for bulk materials in a nuclear reprocessing facility. Tank volume calibration functions used in nuclear materials safeguards and accountability programs are typically constructed from several segments, each of which is estimated independently. Ideally, the segments correspond to structural features in the tank. In this paper the authors use an extension of the Thomas-Liebetrau model to estimate the entire calibration function in a single step. This procedure automatically takes significant run-to-run differences into account and yields an estimate of the entire calibration function in one operation. As with other procedures, the first step is to define suitable calibration segments. Next, a polynomial of low degree is specified for each segment. In contrast with the conventional practice of constructing a separate model for each segment, this information is used to set up the design matrix for a single model that encompasses all of the calibration data. Estimation of the model parameters is then done using conventional statistical methods. The method described here has several advantages over traditional methods. First, modeled run-to-run differences can be taken into account automatically at the estimation step. Second, no interpolation is required between successive segments. Third, variance estimates are based on all the data, rather than that from a single segment, with the result that discontinuities in confidence intervals at segment boundaries are eliminated. Fourth, the restrictive assumption of the Thomas-Liebetrau method, that the measured volumes be the same for all runs, is not required. Finally, the proposed methods are readily implemented using standard statistical procedures and widely-used software packages

One-Step Method for Preparation of Magnetic Nanoparticles Coated with Chitosan

Directory of Open Access Journals (Sweden)

Karla M. Gregorio-Jauregui

2012-01-01

Full Text Available Preparation of magnetic nanoparticles coated with chitosan in one step by the coprecipitation method in the presence of different chitosan concentrations is reported here. Obtaining of magnetic superparamagnetic nanoparticles was confirmed by X-ray diffraction and magnetic measurements. Scanning transmission electron microscopy allowed to identify spheroidal nanoparticles with around 10-11 nm in average diameter. Characterization of the products by Fourier transform infrared spectroscopy demonstrated that composite chitosan-magnetic nanoparticles were obtained. Chitosan content in obtained nanocomposites was estimated by thermogravimetric analysis. The nanocomposites were tested in Pb2+ removal from a PbCl2 aqueous solution, showing a removal efficacy up to 53.6%. This work provides a simple method for chitosan-coated nanoparticles obtaining, which could be useful for heavy metal ions removal from water.

Self-seeded single-frequency laser peening method

Science.gov (United States)

DAne, C Brent; Hackey, Lloyd A; Harris, Fritz B

2012-06-26

A method of operating a laser to obtain an output pulse having a single wavelength, comprises inducing an intracavity loss into a laser resonator having an amount that prevents oscillation during a time that energy from the pump source is being stored in the gain medium. Gain is built up in the gain medium with energy from the pump source until formation of a single-frequency relaxation oscillation pulse in the resonator. Upon detection of the onset of the relaxation oscillation pulse, the intracavity loss is reduced, such as by Q-switching, so that the built-up gain stored in the gain medium is output from the resonator in the form of an output pulse at a single frequency. An electronically controllable output coupler is controlled to affect output pulse characteristics. The laser acts a master oscillator in a master oscillator power amplifier configuration. The laser is used for laser peening.

EnsembleGASVR: A novel ensemble method for classifying missense single nucleotide polymorphisms

KAUST Repository

Rapakoulia, Trisevgeni

2014-04-26

Motivation: Single nucleotide polymorphisms (SNPs) are considered the most frequently occurring DNA sequence variations. Several computational methods have been proposed for the classification of missense SNPs to neutral and disease associated. However, existing computational approaches fail to select relevant features by choosing them arbitrarily without sufficient documentation. Moreover, they are limited to the problem ofmissing values, imbalance between the learning datasets and most of them do not support their predictions with confidence scores. Results: To overcome these limitations, a novel ensemble computational methodology is proposed. EnsembleGASVR facilitates a twostep algorithm, which in its first step applies a novel evolutionary embedded algorithm to locate close to optimal Support Vector Regression models. In its second step, these models are combined to extract a universal predictor, which is less prone to overfitting issues, systematizes the rebalancing of the learning sets and uses an internal approach for solving the missing values problem without loss of information. Confidence scores support all the predictions and the model becomes tunable by modifying the classification thresholds. An extensive study was performed for collecting the most relevant features for the problem of classifying SNPs, and a superset of 88 features was constructed. Experimental results show that the proposed framework outperforms well-known algorithms in terms of classification performance in the examined datasets. Finally, the proposed algorithmic framework was able to uncover the significant role of certain features such as the solvent accessibility feature, and the top-scored predictions were further validated by linking them with disease phenotypes. © The Author 2014.

Effect of caries-affected dentin on one-step universal and multi-step etch-and-rinse adhesives’ bond strength

Directory of Open Access Journals (Sweden)

Clecila MÜLLER

2017-10-01

Full Text Available Abstract Objective To evaluate the influence of caries-affected dentin on bond strength of a universal one-step and a multi-step etch-and-rinse adhesive system. Material and method Enamel of 60 third human molars with and without caries was removed to expose dentin. The teeth were randomly assigned to six groups: Single Bond Universal (3M ESPE, St. Paul, MN, USA in etch-and-rinse and in self-etch mode and Prime & Bond NT (Dentsply Co, Konstanz, Germany, all on sound and caries-affected dentin. Smear layer of the 30 sound dentin specimens was standardized by polishing with 600-grit SiC paper under water cooling. Residual infected dentin of the 30 caries-affected specimens was removed with a number 4 CA carbide bur until no caries smooth tissue was detectable by tactile-visual inspection. Cylinders of a light cured composite resin (Filtek Z350 XT, 3M ESPE were built up using starch tubes and microshear test was performed until failure. The data was analyzed by one-way ANOVA and Tukey’s post hoc test. Result Significant differences in microshear bond strength (μSBS were observed for the caries-affected groups, but not for sound dentin. The μSBS of Single Bond Universal were not influenced by the application protocol on sound dentin, however they were lower in the caries-affected group with both application protocols. The μSBS for Prime & Bond NT was not influenced by the dentin conditions. Conclusion Caries-affected dentin decrease in bond strength of Single Bond Universal in comparison to sound dentin. The bond strength of Prime & Bond NT was not altered by substrate conditions.

Imaging by the SSFSE single slice method at different viscosities of bile

International Nuclear Information System (INIS)

Kubo, Hiroya; Usui, Motoki; Fukunaga, Kenichi; Yamamoto, Naruto; Ikegami, Toshimi

2001-01-01

The single shot fast spin echo single thick slice method (single slice method) is a technique that visualizes the water component alone using a heavy T 2 . However, this method is considered to be markedly affected by changes in the viscosity of the material because a very long TE is used, and changes in the T 2 value, which are related to viscosity, directly affect imaging. In this study, we evaluated the relationship between the effects of TE and the T 2 value of bile in the single slice method and also examined the relationship between the signal intensity of bile on T 1 - and T 2 -weighted images and imaging by MR cholangiography (MRC). It was difficult to image bile with high viscosities at a usual effective TE level of 700-1,500 ms. With regard to the relationship between the signal intensity of bile and MRC imaging, all T 2 values of the bile samples showing relatively high signal intensities on the T 1 -weighted images suggested high viscosities, and MRC imaging of these bile samples was poor. In conclusion, MRC imaging of bile with high viscosities was poor with the single slice method. Imaging by the single slice method alone of bile showing a relatively high signal intensity on T 1 -weighted images should be avoided, and combination with other MRC sequences should be used. (author)

Rapid one-step selection method for generating nucleic acid aptamers: development of a DNA aptamer against α-bungarotoxin.

Directory of Open Access Journals (Sweden)

Lasse H Lauridsen

Full Text Available BACKGROUND: Nucleic acids based therapeutic approaches have gained significant interest in recent years towards the development of therapeutics against many diseases. Recently, research on aptamers led to the marketing of Macugen®, an inhibitor of vascular endothelial growth factor (VEGF for the treatment of age related macular degeneration (AMD. Aptamer technology may prove useful as a therapeutic alternative against an array of human maladies. Considering the increased interest in aptamer technology globally that rival antibody mediated therapeutic approaches, a simplified selection, possibly in one-step, technique is required for developing aptamers in limited time period. PRINCIPAL FINDINGS: Herein, we present a simple one-step selection of DNA aptamers against α-bungarotoxin. A toxin immobilized glass coverslip was subjected to nucleic acid pool binding and extensive washing followed by PCR enrichment of the selected aptamers. One round of selection successfully identified a DNA aptamer sequence with a binding affinity of 7.58 µM. CONCLUSION: We have demonstrated a one-step method for rapid production of nucleic acid aptamers. Although the reported binding affinity is in the low micromolar range, we believe that this could be further improved by using larger targets, increasing the stringency of selection and also by combining a capillary electrophoresis separation prior to the one-step selection. Furthermore, the method presented here is a user-friendly, cheap and an easy way of deriving an aptamer unlike the time consuming conventional SELEX-based approach. The most important application of this method is that chemically-modified nucleic acid libraries can also be used for aptamer selection as it requires only one enzymatic step. This method could equally be suitable for developing RNA aptamers.

Single-step synthesis of [18F]haloperidol from the chloro-precursor and its applications in PET imaging of a cat's brain

International Nuclear Information System (INIS)

Hashizume, Kazunari; Tamakawa, Hiroki; Hashimoto, Naoto; Miyake, Yoshihiro

1997-01-01

We have established a convenient synthesis process for the synthesis of [ 18 F]haloperidol using a single-step 18 F - for -Cl exchange reaction and a new elution system for the preparative high performance liquid chromatography (HPLC) using C18 bonded vinylalcohol copolymer gel (ODP) and a basic eluent. We successfully applied the product to cat-PET study and got clear images of the striatum, showing the usefulness of this synthesis. (author)

Two-step reconstruction method using global optimization and conjugate gradient for ultrasound-guided diffuse optical tomography.

Science.gov (United States)

Tavakoli, Behnoosh; Zhu, Quing

2013-01-01

Ultrasound-guided diffuse optical tomography (DOT) is a promising method for characterizing malignant and benign lesions in the female breast. We introduce a new two-step algorithm for DOT inversion in which the optical parameters are estimated with the global optimization method, genetic algorithm. The estimation result is applied as an initial guess to the conjugate gradient (CG) optimization method to obtain the absorption and scattering distributions simultaneously. Simulations and phantom experiments have shown that the maximum absorption and reduced scattering coefficients are reconstructed with less than 10% and 25% errors, respectively. This is in contrast with the CG method alone, which generates about 20% error for the absorption coefficient and does not accurately recover the scattering distribution. A new measure of scattering contrast has been introduced to characterize benign and malignant breast lesions. The results of 16 clinical cases reconstructed with the two-step method demonstrates that, on average, the absorption coefficient and scattering contrast of malignant lesions are about 1.8 and 3.32 times higher than the benign cases, respectively.

One-Step Protein Conjugation to Upconversion Nanoparticles.

Science.gov (United States)

Lu, Jie; Chen, Yinghui; Liu, Deming; Ren, Wei; Lu, Yiqing; Shi, Yu; Piper, James; Paulsen, Ian; Jin, Dayong

2015-10-20

The emerging upconversion nanoparticles offer a fascinating library of ultrasensitive luminescent probes for a range of biotechnology applications from biomarker discovery to single molecule tracking, early disease diagnosis, deep tissue imaging, and drug delivery and therapies. The effective bioconjugation of inorganic nanoparticles to the molecule-specific proteins, free of agglomeration, nonspecific binding, or biomolecule deactivation, is crucial for molecular recognition of target molecules or cells. The current available protocols require multiple steps which can lead to low probe stability, specificity, and reproducibility. Here we report a simple and rapid protein bioconjugation method based on a one-step ligand exchange using the DNAs as the linker. Our method benefits from the robust DNA-protein conjugates as well as from multiple ions binding capability. Protein can be preconjugated via an amino group at the 3' end of a synthetic DNA molecule, so that the 5' end phosphoric acid group and multiple phosphate oxygen atoms in the phosphodiester bonds are exposed to replace the oleic acid ligands on the surface of upconversion nanoparticles due to their stronger chelating capability to lanthanides. We demonstrated that our method can efficiently pull out the upconversion nanoparticles from organic solvent into an aqueous phase. The upconversion nanoparticles then become hydrophilic, stable, and specific biomolecules recognition. This allows us to successfully functionalize the upconversion nanoparticles with horseradish peroxidise (HRP) for catalytic colorimetric assay and for streptavidin (SA)-biotin immunoassays.

The Seven Step Strategy

Science.gov (United States)

Schaffer, Connie

2017-01-01

Many well-intended instructors use Socratic or leveled questioning to facilitate the discussion of an assigned reading. While this engages a few students, most can opt to remain silent. The seven step strategy described in this article provides an alternative to classroom silence and engages all students. Students discuss a single reading as they…

Methods of forming single source precursors, methods of forming polymeric single source precursors, and single source precursors and intermediate products formed by such methods

Science.gov (United States)

Fox, Robert V.; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin; Margulieux, Kelsey R.; Holland, Andrew W.

2012-12-04

Methods of forming single source precursors (SSPs) include forming intermediate products having the empirical formula 1/2{L.sub.2N(.mu.-X).sub.2M'X.sub.2}.sub.2, and reacting MER with the intermediate products to form SSPs of the formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2, wherein L is a Lewis base, M is a Group IA atom, N is a Group IB atom, M' is a Group IIIB atom, each E is a Group VIB atom, each X is a Group VIIA atom or a nitrate group, and each R group is an alkyl, aryl, vinyl, (per)fluoro alkyl, (per)fluoro aryl, silane, or carbamato group. Methods of forming polymeric or copolymeric SSPs include reacting at least one of HE.sup.1R.sup.1E.sup.1H and MER with one or more substances having the empirical formula L.sub.2N(.mu.-ER).sub.2M'(ER).sub.2 or L.sub.2N(.mu.-X).sub.2M'(X).sub.2 to form a polymeric or copolymeric SSP. New SSPs and intermediate products are formed by such methods.

Single-Step Fabrication Using a Phase Inversion Method of Poly(vinylidene fluoride) (PVDF) Activated Carbon Air Cathodes for Microbial Fuel Cells

KAUST Repository

Yang, Wulin; He, Weihua; Zhang, Fang; Hickner, Michael A.; Logan, Bruce E.

2014-01-01

Air cathodes used in microbial fuel cells (MFCs) need to have high catalytic activity for oxygen reduction, but they must also be easy to manufacture, inexpensive, and watertight. A simple one-step, phase inversion process was used here to construct

A successful backward step correlates with hip flexion moment of supporting limb in elderly people.

Science.gov (United States)

Takeuchi, Yahiko

2018-01-01

The objective of this study was to determine the positional relationship between the center of mass (COM) and the center of pressure (COP) at the time of step landing, and to examine their relationship with the joint moments exerted by the supporting limb, with regard to factors of the successful backward step response. The study population comprised 8 community-dwelling elderly people that were observed to take successive multi steps after the landing of a backward stepping. Using a motion capture system and force plate, we measured the COM, COP and COM-COP deviation distance on landing during backward stepping. In addition, we measured the moment of the supporting limb joint during backward stepping. The multi-step data were compared with data from instances when only one step was taken (single-step). Variables that differed significantly between the single- and multi-step data were used as objective variables and the joint moments of the supporting limb were used as explanatory variables in single regression analyses. The COM-COP deviation in the anteroposterior was significantly larger in the single-step. A regression analysis with COM-COP deviation as the objective variable obtained a significant regression equation in the hip flexion moment (R2 = 0.74). The hip flexion moment of supporting limb was shown to be a significant explanatory variable in both the PS and SS phases for the relationship with COM-COP distance. This study found that to create an appropriate backward step response after an external disturbance (i.e. the ability to stop after 1 step), posterior braking of the COM by a hip flexion moment are important during the single-limbed standing phase.

High-resolution wave-theory-based ultrasound reflection imaging using the split-step fourier and globally optimized fourier finite-difference methods

Science.gov (United States)

Huang, Lianjie

2013-10-29

Methods for enhancing ultrasonic reflection imaging are taught utilizing a split-step Fourier propagator in which the reconstruction is based on recursive inward continuation of ultrasonic wavefields in the frequency-space and frequency-wave number domains. The inward continuation within each extrapolation interval consists of two steps. In the first step, a phase-shift term is applied to the data in the frequency-wave number domain for propagation in a reference medium. The second step consists of applying another phase-shift term to data in the frequency-space domain to approximately compensate for ultrasonic scattering effects of heterogeneities within the tissue being imaged (e.g., breast tissue). Results from various data input to the method indicate significant improvements are provided in both image quality and resolution.

Genome-wide association mapping including phenotypes from relatives without genotypes in a single-step (ssGWAS for 6-week body weight in broiler chickens

Directory of Open Access Journals (Sweden)

Huiyu eWang

2014-05-01

Full Text Available The purpose of this study was to compare results obtained from various methodologies for genome-wide association studies, when applied to real data, in terms of number and commonality of regions identified and their genetic variance explained, computational speed, and possible pitfalls in interpretations of results. Methodologies include: two iteratively reweighted single-step genomic BLUP procedures (ssGWAS1 and ssGWAS2, a single-marker model (CGWAS, and BayesB. The ssGWAS methods utilize genomic breeding values (GEBVs based on combined pedigree, genomic and phenotypic information, while CGWAS and BayesB only utilize phenotypes from genotyped animals or pseudo-phenotypes. In this study, ssGWAS was performed by converting GEBVs to SNP marker effects. Unequal variances for markers were incorporated for calculating weights into a new genomic relationship matrix. SNP weights were refined iteratively. The data was body weight at 6 weeks on 274,776 broiler chickens, of which 4553 were genotyped using a 60k SNP chip. Comparison of genomic regions was based on genetic variances explained by local SNP regions (20 SNPs. After 3 iterations, the noise was greatly reduced of ssGWAS1 and results are similar to that of CGWAS, with 4 out of the top 10 regions in common. In contrast, for BayesB, the plot was dominated by a single region explaining 23.1% of the genetic variance. This same region was found by ssGWAS1 with the same rank, but the amount of genetic variation attributed to the region was only 3%. These finding emphasize the need for caution when comparing and interpreting results from various methods, and highlight that detected associations, and strength of association, strongly depends on methodologies and details of implementations. BayesB appears to overly shrink regions to zero, while overestimating the amount of genetic variation attributed to the remaining SNP effects. The real world is most likely a compromise between methods and remains to

Imaging by the SSFSE single slice method at different viscosities of bile

Energy Technology Data Exchange (ETDEWEB)

Kubo, Hiroya; Usui, Motoki; Fukunaga, Kenichi; Yamamoto, Naruto; Ikegami, Toshimi [Kawasaki Hospital, Kobe (Japan)

2001-11-01

The single shot fast spin echo single thick slice method (single slice method) is a technique that visualizes the water component alone using a heavy T{sub 2}. However, this method is considered to be markedly affected by changes in the viscosity of the material because a very long TE is used, and changes in the T{sub 2} value, which are related to viscosity, directly affect imaging. In this study, we evaluated the relationship between the effects of TE and the T{sub 2} value of bile in the single slice method and also examined the relationship between the signal intensity of bile on T{sub 1}- and T{sub 2}-weighted images and imaging by MR cholangiography (MRC). It was difficult to image bile with high viscosities at a usual effective TE level of 700-1,500 ms. With regard to the relationship between the signal intensity of bile and MRC imaging, all T{sub 2} values of the bile samples showing relatively high signal intensities on the T{sub 1}-weighted images suggested high viscosities, and MRC imaging of these bile samples was poor. In conclusion, MRC imaging of bile with high viscosities was poor with the single slice method. Imaging by the single slice method alone of bile showing a relatively high signal intensity on T{sub 1}-weighted images should be avoided, and combination with other MRC sequences should be used. (author)

Method: a single nucleotide polymorphism genotyping method for Wheat streak mosaic virus

Science.gov (United States)

2012-01-01

Background The September 11, 2001 attacks on the World Trade Center and the Pentagon increased the concern about the potential for terrorist attacks on many vulnerable sectors of the US, including agriculture. The concentrated nature of crops, easily obtainable biological agents, and highly detrimental impacts make agroterrorism a potential threat. Although procedures for an effective criminal investigation and attribution following such an attack are available, important enhancements are still needed, one of which is the capability for fine discrimination among pathogen strains. The purpose of this study was to develop a molecular typing assay for use in a forensic investigation, using Wheat streak mosaic virus (WSMV) as a model plant virus. Method This genotyping technique utilizes single base primer extension to generate a genetic fingerprint. Fifteen single nucleotide polymorphisms (SNPs) within the coat protein and helper component-protease genes were selected as the genetic markers for this assay. Assay optimization and sensitivity testing was conducted using synthetic targets. WSMV strains and field isolates were collected from regions around the world and used to evaluate the assay for discrimination. The assay specificity was tested against a panel of near-neighbors consisting of genetic and environmental near-neighbors. Result Each WSMV strain or field isolate tested produced a unique SNP fingerprint, with the exception of three isolates collected within the same geographic location that produced indistinguishable fingerprints. The results were consistent among replicates, demonstrating the reproducibility of the assay. No SNP fingerprints were generated from organisms included in the near-neighbor panel, suggesting the assay is specific for WSMV. Using synthetic targets, a complete profile could be generated from as low as 7.15 fmoles of cDNA. Conclusion The molecular typing method presented is one tool that could be incorporated into the forensic

Combination of electromembrane extraction and liquid-phase microextraction in a single step: Simultaneous group separation of acidic and basic drugs

DEFF Research Database (Denmark)

Huang, Chuixiu; Seip, Knut Fredrik; Gjelstad, Astrid

2015-01-01

at high concentration. This approach was further investigated from human plasma. Extraction recoveries were strongly dependent on dilution of plasma with buffer and on extraction time. Finally, this simultaneous EME/LPME approach was evaluated in combination with liquid chromatography (LC......Electromembrane extraction (EME) and liquid-phase microextraction (LPME) were combined in a single step for the first time to realize simultaneous and clear group separation of basic and acidic drugs. Using 2-nitrophenyl octyl ether as the supported liquid membrane (SLM) for EME and dihexyl ether...

In situ synthesis carbonated hydroxyapatite layers on enamel slices with acidic amino acids by a novel two-step method

International Nuclear Information System (INIS)

Wu, Xiaoguang; Zhao, Xu; Li, Yi; Yang, Tao; Yan, Xiujuan; Wang, Ke

2015-01-01

In situ fabrication of carbonated hydroxyapatite (CHA) remineralization layer on an enamel slice was completed in a novel, biomimetic two-step method. First, a CaCO 3 layer was synthesized on the surface of demineralized enamel using an acidic amino acid (aspartic acid or glutamate acid) as a soft template. Second, at the same concentration of the acidic amino acid, rod-like carbonated hydroxyapatite was produced with the CaCO 3 layer as a sacrificial template and a reactant. The morphology, crystallinity and other physicochemical properties of the crystals were characterized using field emission scanning electron microscopy (FESEM), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) and energy-dispersive X-ray analysis (EDAX), respectively. Acidic amino acid could promote the uniform deposition of hydroxyapatite with rod-like crystals via absorption of phosphate and carbonate ions from the reaction solution. Moreover, compared with hydroxyapatite crystals coated on the enamel when synthesized by a one-step method, the CaCO 3 coating that was synthesized in the first step acted as an active bridge layer and sacrificial template. It played a vital role in orienting the artificial coating layer through the template effect. The results show that the rod-like carbonated hydroxyapatite crystals grow into bundles, which are similar in size and appearance to prisms in human enamel, when using the two-step method with either aspartic acid or acidic glutamate (20.00 mmol/L). - Graphical abstract: FESEM images of enamel slices etched for 60 s and repaired by the two-step method with Glu concentration of 20.00 mmol/L. (A) The boundary (dotted line) of the repaired areas (b) and unrepaired areas (a). (Some selected areas of etched enamel slices were coated with a nail polish before the reaction, which was removed by acetone after the reaction); (B) high magnification image of Ga, (C) high magnification image of Gb. In situ fabrication of carbonated

In situ synthesis carbonated hydroxyapatite layers on enamel slices with acidic amino acids by a novel two-step method

Energy Technology Data Exchange (ETDEWEB)

Wu, Xiaoguang [Department of Pediatric Dentistry, The Hospital of Stomatology, Jilin University, Changchun 130021 (China); Zhao, Xu [College of Chemistry, Jilin University, Changchun 130021 (China); Li, Yi, E-mail: lyi99@jlu.edu.cn [Department of Pediatric Dentistry, The Hospital of Stomatology, Jilin University, Changchun 130021 (China); Yang, Tao [Department of Stomatology, Children' s Hospital of Changchun, 130051 (China); Yan, Xiujuan; Wang, Ke [Department of Pediatric Dentistry, The Hospital of Stomatology, Jilin University, Changchun 130021 (China)

2015-09-01

In situ fabrication of carbonated hydroxyapatite (CHA) remineralization layer on an enamel slice was completed in a novel, biomimetic two-step method. First, a CaCO{sub 3} layer was synthesized on the surface of demineralized enamel using an acidic amino acid (aspartic acid or glutamate acid) as a soft template. Second, at the same concentration of the acidic amino acid, rod-like carbonated hydroxyapatite was produced with the CaCO{sub 3} layer as a sacrificial template and a reactant. The morphology, crystallinity and other physicochemical properties of the crystals were characterized using field emission scanning electron microscopy (FESEM), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) and energy-dispersive X-ray analysis (EDAX), respectively. Acidic amino acid could promote the uniform deposition of hydroxyapatite with rod-like crystals via absorption of phosphate and carbonate ions from the reaction solution. Moreover, compared with hydroxyapatite crystals coated on the enamel when synthesized by a one-step method, the CaCO{sub 3} coating that was synthesized in the first step acted as an active bridge layer and sacrificial template. It played a vital role in orienting the artificial coating layer through the template effect. The results show that the rod-like carbonated hydroxyapatite crystals grow into bundles, which are similar in size and appearance to prisms in human enamel, when using the two-step method with either aspartic acid or acidic glutamate (20.00 mmol/L). - Graphical abstract: FESEM images of enamel slices etched for 60 s and repaired by the two-step method with Glu concentration of 20.00 mmol/L. (A) The boundary (dotted line) of the repaired areas (b) and unrepaired areas (a). (Some selected areas of etched enamel slices were coated with a nail polish before the reaction, which was removed by acetone after the reaction); (B) high magnification image of Ga, (C) high magnification image of Gb. In situ fabrication of

Method of stabilizing single channel analyzers

International Nuclear Information System (INIS)

Fasching, G.E.; Patton, G.H.

1975-01-01

A method and the apparatus to reduce the drift of single channel analyzers are described. Essentially, this invention employs a time-sharing or multiplexing technique to insure that the outputs from two single channel analyzers (SCAS) maintain the same count ratio regardless of variations in the threshold voltage source or voltage changes, the multiplexing technique is accomplished when a flip flop, actuated by a clock, changes state to switch the output from the individual SCAS before these outputs are sent to a ratio counting scalar. In the particular system embodiment disclosed that illustrates this invention, the sulfur content of coal is determined by subjecting the coal to radiation from a neutron producing source. A photomultiplier and detector system equates the transmitted gamma radiation to an analog voltage signal and sends the same signal after amplification, to a SCA system that contains the invention. Therein, at least two single channel analyzers scan the analog signal over different parts of a spectral region. The two outputs may then be sent to a digital multiplexer so that the output from the multiplexer contains counts falling within two distinct segments of the region. By dividing the counts from the multiplexer by each other, the percentage of sulfur within the coal sample under observation may be determined. (U.S.)

Single-step laser deposition of functionally graded coating by dual ‘wire powder’ or ‘powder powder’ feeding—A comparative study

Science.gov (United States)

Syed, Waheed Ul Haq; Pinkerton, Andrew J.; Liu, Zhu; Li, Lin

2007-07-01

The creation of iron-copper (Fe-Cu) alloys has practical application in improving the surface heat conduction and corrosion resistance of, for example, conformal cooling channels in steel moulds, but is difficult to achieve because the elements have got low inter-solubility and are prone to solidification cracking. Previous work by these authors has reported a method to produce a graded iron-nickel-copper coating in a single-step by direct diode laser deposition (DLD) of nickel wire and copper powder as a combined feedstock. This work investigates whether dual powder feeds can be used in that process to afford greater geometric flexibility and compares attributes of the 'nickel wire and copper powder' and 'nickel powder and copper powder' processes for deposition on a H13 tool steel substrate. In wire-powder deposition, a higher temperature developed in the melt pool causing a clad with a smooth gradient structure. The nickel powder in powder-powder deposition did not impart much heat into the melt pool so the melt pool solidified with sharp composition boundaries due to single metal melting in some parts. In wire-powder experiments, a graded structure was obtained by varying the flow rates of wire and powder. However, a graded structure was not realised in powder-powder experiments by varying either the feed or the directions. Reasons for the differences and flow patterns in the melt pools and their effect on final part properties of parts produced are discussed.

Two-step extraction method for lead isotope fractionation to reveal anthropogenic lead pollution.

Science.gov (United States)

Katahira, Kenshi; Moriwaki, Hiroshi; Kamura, Kazuo; Yamazaki, Hideo

2018-05-28

This study developed the 2-step extraction method which eluted the Pb adsorbing on the surface of sediments in the first solution by aqua regia and extracted the Pb absorbed inside particles into the second solution by mixed acid of nitric acid, hydrofluoric acid and hydrogen peroxide solution. We applied the method to sediments in the enclosed water area and found out that the isotope ratios of Pb in the second solution represented those of natural origin. This advantage of the method makes it possible to distinguish the Pb between natural origin and anthropogenic source on the basis of the isotope ratios. The results showed that the method was useful to discuss the Pb sources and that anthropogenic Pb in the sediment samples analysed was mainly derived from China because of transboundary air pollution.

General Methods for Analysis of Sequential “n-step” Kinetic Mechanisms: Application to Single Turnover Kinetics of Helicase-Catalyzed DNA Unwinding

Science.gov (United States)

Lucius, Aaron L.; Maluf, Nasib K.; Fischer, Christopher J.; Lohman, Timothy M.

2003-01-01

Helicase-catalyzed DNA unwinding is often studied using “all or none” assays that detect only the final product of fully unwound DNA. Even using these assays, quantitative analysis of DNA unwinding time courses for DNA duplexes of different lengths, L, using “n-step” sequential mechanisms, can reveal information about the number of intermediates in the unwinding reaction and the “kinetic step size”, m, defined as the average number of basepairs unwound between two successive rate limiting steps in the unwinding cycle. Simultaneous nonlinear least-squares analysis using “n-step” sequential mechanisms has previously been limited by an inability to float the number of “unwinding steps”, n, and m, in the fitting algorithm. Here we discuss the behavior of single turnover DNA unwinding time courses and describe novel methods for nonlinear least-squares analysis that overcome these problems. Analytic expressions for the time courses, fss(t), when obtainable, can be written using gamma and incomplete gamma functions. When analytic expressions are not obtainable, the numerical solution of the inverse Laplace transform can be used to obtain fss(t). Both methods allow n and m to be continuous fitting parameters. These approaches are generally applicable to enzymes that translocate along a lattice or require repetition of a series of steps before product formation. PMID:14507688

Enhanced Water Oxidation Photoactivity of Nano-Architectured α-Fe2O3-WO3 Composite Synthesized by Single-Step Hydrothermal Method

Science.gov (United States)

Rahman, Gul; Joo, Oh-Shim; Chae, Sang Youn; Shah, Anwar-ul-Haq Ali; Mian, Shabeer Ahmad

2018-04-01

This study reports the one-step in situ synthesis of a hematite-tungsten oxide (α-Fe2O3-WO3) composite on fluorine-doped tin oxide substrate via a simple hydrothermal method. Scanning electron microscopy images indicated that the addition of tungsten (W) precursor into the reaction mixture altered the surface morphology from nanorods to nanospindles. Energy-dispersive x-ray spectroscopy analysis confirmed the presence of W content in the composite. From the ultraviolet-visible spectrum of α-Fe2O3-WO3, it was observed that absorption began at ˜ 600 nm which corresponded to the bandgap energy of ˜ 2.01 eV. The α-Fe2O3-WO3 electrode demonstrated superior performance, with water oxidation photocurrent density of 0.80 mA/cm2 (at 1.6 V vs. reversible hydrogen electrode under standard illumination conditions; AM 1.5G, 100 mW/cm2) which is 2.4 times higher than α-Fe2O3 (0.34 mA/cm2). This enhanced water oxidation performance can be attributed to the better charge separation properties in addition to the large interfacial area of small-sized particles present in the α-Fe2O3-WO3 nanocomposite film.

Two-Step Injection Method for Collecting Digital Evidence in Digital Forensics

Directory of Open Access Journals (Sweden)

Nana Rachmana Syambas

2015-01-01

Full Text Available In digital forensic investigations, the investigators take digital evidence from computers, laptops or other electronic goods. There are many complications when a suspect or related person does not want to cooperate or has removed digital evidence. A lot of research has been done with the goal of retrieving data from flash memory or other digital storage media from which the content has been deleted. Unfortunately, such methods cannot guarantee that all data will be recovered. Most data can only be recovered partially and sometimes not perfectly, so that some or all files cannot be opened. This paper proposes the development of a new method for the retrieval of digital evidence called the Two-Step Injection method (TSI. It focuses on the prevention of the loss of digital evidence through the deletion of data by suspects or other parties. The advantage of this method is that the system works in secret and can be combined with other digital evidence applications that already exist, so that the accuracy and completeness of the resulting digital evidence can be improved. An experiment to test the effectiveness of the method was set up. The developed TSI system worked properly and had a 100% success rate.

Determination of Sintered (Th,U)O2 Pellet at the Grain Growth Step

International Nuclear Information System (INIS)

Indrati-Y, Tundjung; Pristi-Hartati, Murdani; Ari-Handayani; Ginting, Aslina Br

2000-01-01

The determination of sintered (Th,U)O 2 pellet at the grain growth stephave been done by dilatometer and Scanning Electron Microscope (SEM). Thecalculation method based on the densification curve and quantitativemetallurgy. The green pellet be produced by single action compaction. Itspellet was heated on the dilatometer with heating rate 11 o C/minute and inthe argon atmosphere, 2 liters/hour. The activation energy at thedensification step can be calculated by densification curve only, but theactivation energy at the grain growth step can be calculated by densificationcurve or quantitative metallurgy. The capability of the dilatometer can beoperated until 1200 o C, so the densification curve based on the experiencecan be used to calculate activation energy at the densification step, 4.492kcal/mole. The activation energy at the grain growth step, which is 25.277kcal/mole, can be predicted by trial and error on n value. That activationenergy is almost the same with activation energy that based on thequantitative metallurgy method 25.042 kcal/mole. All of the activation energyfor the (Th,U)O 2 pellet sintering process is 29.769 kcal/mole. (author)

Frequency guided methods for demodulation of a single fringe pattern.

Science.gov (United States)

Wang, Haixia; Kemao, Qian

2009-08-17

Phase demodulation from a single fringe pattern is a challenging task but of interest. A frequency-guided regularized phase tracker and a frequency-guided sequential demodulation method with Levenberg-Marquardt optimization are proposed to demodulate a single fringe pattern. Demodulation path guided by the local frequency from the highest to the lowest is applied in both methods. Since critical points have low local frequency values, they are processed last so that the spurious sign problem caused by these points is avoided. These two methods can be considered as alternatives to the effective fringe follower regularized phase tracker. Demodulation results from one computer-simulated and two experimental fringe patterns using the proposed methods will be demonstrated. (c) 2009 Optical Society of America

Adaptive step-size algorithm for Fourier beam-propagation method with absorbing boundary layer of auto-determined width.

Science.gov (United States)

Learn, R; Feigenbaum, E

2016-06-01

Two algorithms that enhance the utility of the absorbing boundary layer are presented, mainly in the framework of the Fourier beam-propagation method. One is an automated boundary layer width selector that chooses a near-optimal boundary size based on the initial beam shape. The second algorithm adjusts the propagation step sizes based on the beam shape at the beginning of each step in order to reduce aliasing artifacts.

Method: a single nucleotide polymorphism genotyping method for Wheat streak mosaic virus.

Science.gov (United States)

Rogers, Stephanie M; Payton, Mark; Allen, Robert W; Melcher, Ulrich; Carver, Jesse; Fletcher, Jacqueline

2012-05-17

The September 11, 2001 attacks on the World Trade Center and the Pentagon increased the concern about the potential for terrorist attacks on many vulnerable sectors of the US, including agriculture. The concentrated nature of crops, easily obtainable biological agents, and highly detrimental impacts make agroterrorism a potential threat. Although procedures for an effective criminal investigation and attribution following such an attack are available, important enhancements are still needed, one of which is the capability for fine discrimination among pathogen strains. The purpose of this study was to develop a molecular typing assay for use in a forensic investigation, using Wheat streak mosaic virus (WSMV) as a model plant virus. This genotyping technique utilizes single base primer extension to generate a genetic fingerprint. Fifteen single nucleotide polymorphisms (SNPs) within the coat protein and helper component-protease genes were selected as the genetic markers for this assay. Assay optimization and sensitivity testing was conducted using synthetic targets. WSMV strains and field isolates were collected from regions around the world and used to evaluate the assay for discrimination. The assay specificity was tested against a panel of near-neighbors consisting of genetic and environmental near-neighbors. Each WSMV strain or field isolate tested produced a unique SNP fingerprint, with the exception of three isolates collected within the same geographic location that produced indistinguishable fingerprints. The results were consistent among replicates, demonstrating the reproducibility of the assay. No SNP fingerprints were generated from organisms included in the near-neighbor panel, suggesting the assay is specific for WSMV. Using synthetic targets, a complete profile could be generated from as low as 7.15 fmoles of cDNA. The molecular typing method presented is one tool that could be incorporated into the forensic science tool box after a thorough

The method of quick satellite aiming with 3-Steps on the mobile satellite station

Directory of Open Access Journals (Sweden)

Sheng Liang

2017-02-01

Full Text Available The study analyses and concludes the technology of the satellite aiming during real-time broadcast of mobile video.We conclude a method of quick satellite aiming with 3-steps according to practical exercises and users' requirement to meet situation of facts and standardized operation,which can improve efficiency and quality of service.

Real stabilization method for nuclear single-particle resonances

International Nuclear Information System (INIS)

Zhang Li; Zhou Shangui; Meng Jie; Zhao Enguang

2008-01-01

We develop the real stabilization method within the framework of the relativistic mean-field (RMF) model. With the self-consistent nuclear potentials from the RMF model, the real stabilization method is used to study single-particle resonant states in spherical nuclei. As examples, the energies, widths, and wave functions of low-lying neutron resonant states in 120 Sn are obtained. These results are compared with those from the scattering phase-shift method and the analytic continuation in the coupling constant approach and satisfactory agreements are found

An explicit multi-time-stepping algorithm for aerodynamic flows

OpenAIRE

Niemann-Tuitman, B.E.; Veldman, A.E.P.

1997-01-01

An explicit multi-time-stepping algorithm with applications to aerodynamic flows is presented. In the algorithm, in different parts of the computational domain different time steps are taken, and the flow is synchronized at the so-called synchronization levels. The algorithm is validated for aerodynamic turbulent flows. For two-dimensional flows speedups in the order of five with respect to single time stepping are obtained.

Characteristic analysis of laser isotope separation process by two-step photodissociation method

International Nuclear Information System (INIS)

Okamoto, Tsuyoshi; Suzuki, Atsuyuki; Kiyose, Ryohei

1981-01-01

A large number of laser isotope separation experiments have been performed actively in many countries. In this paper, the selective two-step photodissociation method is chosen and simultaneous nonlinear differential equations that express the separation process are solved directly by using computer. Predicted separation factors are investigated in relation to the incident pulse energy and the concentration of desired molecules. Furthermore, the concept of separative work is used to evaluate the results of separation for this method. It is shown from an example of numerical calculation that a very large separation factor can be obtained if the concentration of desired molecules is lowered and two laser pulses to be closely synchronized are not always required in operation for the photodissociation of molecules. (author)

Hybrid single node genetic programming for symbolic regression

NARCIS (Netherlands)

Kubalìk, Jiřì; Alibekov, Eduard; Žegklitz, Jan; Babuska, R.; Nguyen, NT; Kowalczyk, R; Filipe, J

2016-01-01

This paper presents a first step of our research on designing an effective and efficient GP-based method for symbolic regression. First, we propose three extensions of the standard Single Node GP, namely (1) a selection strategy for choosing nodes to be mutated based on depth and performance of

Single-step simultaneous side-by-side placement of a self-expandable metallic stent with a 6-Fr delivery system for unresectable malignant hilar biliary obstruction: a feasibility study.

Science.gov (United States)

Kawakubo, Kazumichi; Kawakami, Hiroshi; Kuwatani, Masaki; Kudo, Taiki; Abe, Yoko; Kawahata, Shuhei; Kubo, Kimitoshi; Kubota, Yoshimasa; Sakamoto, Naoya

2015-02-01

Bilateral self-expandable metallic stent (SEMS) placement for the management of unresectable malignant hilar biliary obstruction (UMHBO) is technically challenging to perform using the existing metallic stents with thick delivery systems. The recently developed 6-Fr delivery systems could facilitate a single-step simultaneous side-by-side placement through the accessory channel of the duodenoscope. The aim of this study was to evaluate the feasibility of this procedure. Between May and September 2013, 13 consecutive patients with UMHBO underwent a single-step simultaneous side-by-side placement of SEMS with the 6-Fr delivery system. The technical success rate, stent patency, and rate of complications were evaluated from the prospectively collected database. Technical success was achieved in 11 (84.6%, 95% confidence interval [CI]: 57.8-95.8) patients. The median procedure time was 25 min. Early and late complications were observed in 23% (one segmental cholangitis and two liver abscesses) and 15% (one segmental cholangitis and one cholecystitis) patients, respectively. Median dysfunction free patency was 263 days (95% CI: 37-263). Five patients (38%) experienced stent occlusion that was successfully managed by endoscopic stent placement. A single-step simultaneous side-by-side placement of SEMS with a 6-Fr delivery system was feasible for the management of UMHBO. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

A new multi-step technique with differential transform method for analytical solution of some nonlinear variable delay differential equations.

Science.gov (United States)

Benhammouda, Brahim; Vazquez-Leal, Hector

2016-01-01

This work presents an analytical solution of some nonlinear delay differential equations (DDEs) with variable delays. Such DDEs are difficult to treat numerically and cannot be solved by existing general purpose codes. A new method of steps combined with the differential transform method (DTM) is proposed as a powerful tool to solve these DDEs. This method reduces the DDEs to ordinary differential equations that are then solved by the DTM. Furthermore, we show that the solutions can be improved by Laplace-Padé resummation method. Two examples are presented to show the efficiency of the proposed technique. The main advantage of this technique is that it possesses a simple procedure based on a few straight forward steps and can be combined with any analytical method, other than the DTM, like the homotopy perturbation method.

Rudimentary simple, single step fabrication of nano-flakes like AgCd alloy electro-catalyst for oxygen reduction reaction in alkaline fuel cell

International Nuclear Information System (INIS)

Bhandary, Nimai; Basu, Suddhasatwa; Ingole, Pravin P.

2016-01-01

In this work, for the first time, we report rudimentary simple, single step fabrication of an electro-catalyst based on AgCd alloy nanoparticles with flakes like geometry which shows highly efficient activity towards oxygen reduction reaction (ORR). A simple potentiostatic deposition method has been employed for co-depositing AgCd alloy nanostructures with flakes like shapes along with dendrites on the surface of carbon fibre paper. The chemico-physical properties of the catalyst are investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDXS). Electro-catalytic activity of AgCd alloy based electro-catalyst towards ORR is studied in alkaline medium by cyclic voltammetry and rotating ring disk electrode (RRDE) technique. Electrochemical in-situ FTIR measurements are also performed to identify the species generated during ORR process. Based on the results from electro-catalysis experiment, it is concluded that nano-alloyed AgCd electrodeposited on carbon paper shows excellent activity for ORR, following four electron pathways with H_2O_2 yield less than 15%. The combination of low cost of Ag and Cd, fast and facile method of its fabrication and higher activity towards ORR makes the AgCd electro-catalyst an attractive catalyst of choice for alkaline fuel cell.

Single molecule measurements of DNA helicase activity with magnetic tweezers and t-test based step-finding analysis

Science.gov (United States)

Seol, Yeonee; Strub, Marie-Paule; Neuman, Keir C.

2016-01-01

Magnetic tweezers is a versatile and easy to implement single-molecule technique that has become increasingly prevalent in the study of nucleic acid based molecular motors. Here, we provide a description of the magnetic tweezers instrument and guidelines for measuring and analyzing DNA helicase activity. Along with experimental methods, we describe a robust method of single-molecule trajectory analysis based on the Student’s t-test that accommodates continuous transitions in addition to the discrete transitions assumed in most widely employed analysis routines. To illustrate the single-molecule unwinding assay and the analysis routine, we provide DNA unwinding measurements of Escherichia coli RecQ helicase under a variety of conditions (Na+, ATP, temperature, and DNA substrate geometry). These examples reveal that DNA unwinding measurements under various conditions can aid in elucidating the unwinding mechanism of DNA helicase but also emphasize that environmental effects on DNA helicase activity must be considered in relation to in vivo activity and mechanism. PMID:27131595

Penyelesaian Persoalan Transportasi Fuzzy Cost Menggunakan Pendekatan Basis Tree dan Metode Nwc-stepping Stone

OpenAIRE

Ari, Maxsi; Herman, Asep

2013-01-01

The issue of transportation is a linier program. Practically, variables of transportation problems may vary that emerges more than single. Fuzzy cost idea in transportation problems is required. The application of basis tree approach and NWC-Stepping Stone method is used to determine a minimum cost of purchase and delivery of commodity occurred for some suppliers. The company can do a cost-saving and be more effective in determining goods purchase from the supplier. The method used is quanti...

Methods for the continuous production of plastic scintillator materials

Science.gov (United States)

Bross, Alan; Pla-Dalmau, Anna; Mellott, Kerry

1999-10-19

Methods for producing plastic scintillating material employing either two major steps (tumble-mix) or a single major step (inline-coloring or inline-doping). Using the two step method, the polymer pellets are mixed with silicone oil, and the mixture is then tumble mixed with the dopants necessary to yield the proper response from the scintillator material. The mixture is then placed in a compounder and compounded in an inert gas atmosphere. The resultant scintillator material is then extruded and pelletized or formed. When only a single step is employed, the polymer pellets and dopants are metered into an inline-coloring extruding system. The mixture is then processed under a inert gas atmosphere, usually argon or nitrogen, to form plastic scintillator material in the form of either scintillator pellets, for subsequent processing, or as material in the direct formation of the final scintillator shape or form.

Comparing a single-stage geocoding method to a multi-stage geocoding method: how much and where do they disagree?

Directory of Open Access Journals (Sweden)

Rice Kenneth

2007-03-01

Full Text Available Abstract Background Geocoding methods vary among spatial epidemiology studies. Errors in the geocoding process and differential match rates may reduce study validity. We compared two geocoding methods using 8,157 Washington State addresses. The multi-stage geocoding method implemented by the state health department used a sequence of local and national reference files. The single-stage method used a single national reference file. For each address geocoded by both methods, we measured the distance between the locations assigned by each method. Area-level characteristics were collected from census data, and modeled as predictors of the discordance between geocoded address coordinates. Results The multi-stage method had a higher match rate than the single-stage method: 99% versus 95%. Of 7,686 addresses were geocoded by both methods, 96% were geocoded to the same census tract by both methods and 98% were geocoded to locations within 1 km of each other by the two methods. The distance between geocoded coordinates for the same address was higher in sparsely populated and low poverty areas, and counties with local reference files. Conclusion The multi-stage geocoding method had a higher match rate than the single-stage method. An examination of differences in the location assigned to the same address suggested that study results may be most sensitive to the choice of geocoding method in sparsely populated or low-poverty areas.

A novel two-step method for screening shade tolerant mutant plants via dwarfism

Directory of Open Access Journals (Sweden)

Wei Li

2016-10-01

Full Text Available When subjected to shade, plants undergo rapid shoot elongation, which often makes them more prone to disease and mechanical damage. Shade-tolerant plants can be difficult to breed; however, they offer a substantial benefit over other varieties in low-light areas. Although perennial ryegrass (Lolium perenne L. is a popular species of turf grasses because of their good appearance and fast establishment, the plant normally does not perform well under shade conditions. It has been reported that, in turfgrass, induced dwarfism can enhance shade tolerance. Here we describe a two-step procedure for isolating shade tolerant mutants of perennial ryegrass by first screening for dominant dwarf mutants, and then screening dwarf plants for shade tolerance. The two-step screening process to isolate shade tolerant mutants can be done efficiently with limited space at early seedling stages, which enables quick and efficient isolation of shade tolerant mutants, and thus facilitates development of shade tolerant new cultivars of turfgrasses. Using the method, we isolated 136 dwarf mutants from 300,000 mutagenized seeds, with 65 being shade tolerant (0.022%. When screened directly for shade tolerance, we recovered only four mutants from a population of 150,000 (0.003% mutagenized seeds. One shade tolerant mutant, shadow-1, was characterized in detail. In addition to dwarfism, shadow-1 and its sexual progeny displayed high degrees of tolerance to both natural and artificial shade. We showed that endogenous gibberellin (GA content in shadow-1 was higher than wild-type controls, and shadow-1 was also partially GA insensitive. Our novel, simple and effective two-step screening method should be applicable to breeding shade tolerant cultivars of turfgrasses, ground covers, and other economically important crop plants that can be used under canopies of existing vegetation to increase productivity per unit area of land.

Current lipid extraction methods are significantly enhanced adding a water treatment step in Chlorella protothecoides.

Science.gov (United States)

Ren, Xiaojie; Zhao, Xinhe; Turcotte, François; Deschênes, Jean-Sébastien; Tremblay, Réjean; Jolicoeur, Mario

2017-02-11

Microalgae have the potential to rapidly accumulate lipids of high interest for the food, cosmetics, pharmaceutical and energy (e.g. biodiesel) industries. However, current lipid extraction methods show efficiency limitation and until now, extraction protocols have not been fully optimized for specific lipid compounds. The present study thus presents a novel lipid extraction method, consisting in the addition of a water treatment of biomass between the two-stage solvent extraction steps of current extraction methods. The resulting modified method not only enhances lipid extraction efficiency, but also yields a higher triacylglycerols (TAG) ratio, which is highly desirable for biodiesel production. Modification of four existing methods using acetone, chloroform/methanol (Chl/Met), chloroform/methanol/H 2 O (Chl/Met/H 2 O) and dichloromethane/methanol (Dic/Met) showed respective lipid extraction yield enhancement of 72.3, 35.8, 60.3 and 60.9%. The modified acetone method resulted in the highest extraction yield, with 68.9 ± 0.2% DW total lipids. Extraction of TAG was particularly improved with the water treatment, especially for the Chl/Met/H 2 O and Dic/Met methods. The acetone method with the water treatment led to the highest extraction level of TAG with 73.7 ± 7.3 µg/mg DW, which is 130.8 ± 10.6% higher than the maximum value obtained for the four classical methods (31.9 ± 4.6 µg/mg DW). Interestingly, the water treatment preferentially improved the extraction of intracellular fractions, i.e. TAG, sterols, and free fatty acids, compared to the lipid fractions of the cell membranes, which are constituted of phospholipids (PL), acetone mobile polar lipids and hydrocarbons. Finally, from the 32 fatty acids analyzed for both neutral lipids (NL) and polar lipids (PL) fractions, it is clear that the water treatment greatly improves NL-to-PL ratio for the four standard methods assessed. Water treatment of biomass after the first solvent extraction step

Cheap arbitrary high order methods for single integrand SDEs

DEFF Research Database (Denmark)

Debrabant, Kristian; Kværnø, Anne

2017-01-01

For a particular class of Stratonovich SDE problems, here denoted as single integrand SDEs, we prove that by applying a deterministic Runge-Kutta method of order $p_d$ we obtain methods converging in the mean-square and weak sense with order $\\lfloor p_d/2\\rfloor$. The reason is that the B-series...

Acceleration of step and linear discontinuous schemes for the method of characteristics in DRAGON5

Directory of Open Access Journals (Sweden)

Alain Hébert

2017-09-01

Full Text Available The applicability of the algebraic collapsing acceleration (ACA technique to the method of characteristics (MOC in cases with scattering anisotropy and/or linear sources was investigated. Previously, the ACA was proven successful in cases with isotropic scattering and uniform (step sources. A presentation is first made of the MOC implementation, available in the DRAGON5 code. Two categories of schemes are available for integrating the propagation equations: (1 the first category is based on exact integration and leads to the classical step characteristics (SC and linear discontinuous characteristics (LDC schemes and (2 the second category leads to diamond differencing schemes of various orders in space. The acceleration of these MOC schemes using a combination of the generalized minimal residual [GMRES(m] method preconditioned with the ACA technique was focused on. Numerical results are provided for a two-dimensional (2D eight-symmetry pressurized water reactor (PWR assembly mockup in the context of the DRAGON5 code.

A multi-step dealloying method to produce nanoporous gold with no volume change and minimal cracking

Energy Technology Data Exchange (ETDEWEB)

Sun Ye [Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506 (United States); Balk, T. John [Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506 (United States)], E-mail: balk@engr.uky.edu

2008-05-15

We report a simple two-step dealloying method for producing bulk nanoporous gold with no volume change and no significant cracking. The galvanostatic dealloying method used here appears superior to potentiostatic methods for fabricating millimeter-scale samples. Care must be taken when imaging the nanoscale, interconnected sponge-like structure with a focused ion beam, as even brief exposure caused immediate and extensive cracking of nanoporous gold, as well as ligament coarsening at the surface00.

Dual color single particle tracking via nanobodies

International Nuclear Information System (INIS)

Albrecht, David; Winterflood, Christian M; Ewers, Helge

2015-01-01

Single particle tracking is a powerful tool to investigate the function of biological molecules by following their motion in space. However, the simultaneous tracking of two different species of molecules is still difficult to realize without compromising the length or density of trajectories, the localization accuracy or the simplicity of the assay. Here, we demonstrate a simple dual color single particle tracking assay using small, bright, high-affinity labeling via nanobodies of accessible targets with widely available instrumentation. We furthermore apply a ratiometric step-size analysis method to visualize differences in apparent membrane viscosity. (paper)

Symplectic integrators with adaptive time steps

Science.gov (United States)

Richardson, A. S.; Finn, J. M.

2012-01-01

In recent decades, there have been many attempts to construct symplectic integrators with variable time steps, with rather disappointing results. In this paper, we identify the causes for this lack of performance, and find that they fall into two categories. In the first, the time step is considered a function of time alone, Δ = Δ(t). In this case, backward error analysis shows that while the algorithms remain symplectic, parametric instabilities may arise because of resonance between oscillations of Δ(t) and the orbital motion. In the second category the time step is a function of phase space variables Δ = Δ(q, p). In this case, the system of equations to be solved is analyzed by introducing a new time variable τ with dt = Δ(q, p) dτ. The transformed equations are no longer in Hamiltonian form, and thus do not benefit from integration methods which would be symplectic for Hamiltonian systems. We analyze two methods for integrating the transformed equations which do, however, preserve the structure of the original equations. The first is an extended phase space method, which has been successfully used in previous studies of adaptive time step symplectic integrators. The second, novel, method is based on a non-canonical mixed-variable generating function. Numerical trials for both of these methods show good results, without parametric instabilities or spurious growth or damping. It is then shown how to adapt the time step to an error estimate found by backward error analysis, in order to optimize the time-stepping scheme. Numerical results are obtained using this formulation and compared with other time-stepping schemes for the extended phase space symplectic method.

Using a Two-Step Method to Measure Transgender Identity in Latin America/the Caribbean, Portugal, and Spain

Science.gov (United States)

Reisner, Sari L.; Biello, Katie; Rosenberger, Joshua G.; Austin, S. Bryn; Haneuse, Sebastien; Perez-Brumer, Amaya; Novak, David S.; Mimiaga, Matthew J.

2014-01-01

Few comparative data are available internationally to examine health differences by transgender identity. A barrier to monitoring the health and well-being of transgender people is the lack of inclusion of measures to assess natal sex/gender identity status in surveys. Data were from a cross-sectional anonymous online survey of members (n > 36,000) of a sexual networking website targeting men who have sex with men in Spanish- and Portuguese-speaking countries/ territories in Latin America/the Caribbean, Portugal, and Spain. Natal sex/gender identity status was assessed using a two-step method (Step 1: assigned birth sex, Step 2: current gender identity). Male-to-female (MTF) and female-to-male (FTM) participants were compared to non-transgender males in age-adjusted regression models on socioeconomic status (SES) (education, income, sex work), masculine gender conformity, psychological health and well-being (lifetime suicidality, past-week depressive distress, positive self-worth, general self-rated health, gender related stressors), and sexual health (HIV-infection, past-year STIs, past-3 month unprotected anal or vaginal sex). The two-step method identified 190 transgender participants (0.54%; 158 MTF, 32 FTM). Of the 12 health-related variables, six showed significant differences between the three groups: SES, masculine gender conformity, lifetime suicidality, depressive distress, positive self-worth, and past-year genital herpes. A two-step approach is recommended for health surveillance efforts to assess natal sex/gender identity status. Cognitive testing to formally validate assigned birth sex and current gender identity survey items in Spanish and Portuguese is encouraged. PMID:25030120

A multi-time-step noise reduction method for measuring velocity statistics from particle tracking velocimetry

Science.gov (United States)

Machicoane, Nathanaël; López-Caballero, Miguel; Bourgoin, Mickael; Aliseda, Alberto; Volk, Romain

2017-10-01

We present a method to improve the accuracy of velocity measurements for fluid flow or particles immersed in it, based on a multi-time-step approach that allows for cancellation of noise in the velocity measurements. Improved velocity statistics, a critical element in turbulent flow measurements, can be computed from the combination of the velocity moments computed using standard particle tracking velocimetry (PTV) or particle image velocimetry (PIV) techniques for data sets that have been collected over different values of time intervals between images. This method produces Eulerian velocity fields and Lagrangian velocity statistics with much lower noise levels compared to standard PIV or PTV measurements, without the need of filtering and/or windowing. Particle displacement between two frames is computed for multiple different time-step values between frames in a canonical experiment of homogeneous isotropic turbulence. The second order velocity structure function of the flow is computed with the new method and compared to results from traditional measurement techniques in the literature. Increased accuracy is also demonstrated by comparing the dissipation rate of turbulent kinetic energy measured from this function against previously validated measurements.

Single-tube library preparation for degraded DNA

DEFF Research Database (Denmark)

Carøe, Christian; Gopalakrishnan, Shyam; Vinner, Lasse

2018-01-01

these obstacles and enable higher throughput are therefore of interest to researchers working with degraded DNA. 2.In this study, we compare four Illumina library preparation protocols, including two “single-tube” methods developed for this study with the explicit aim of improving data quality and reducing...... of chemically damaged and highly fragmented DNA molecules. In particular, the enzymatic reactions and DNA purification steps during library preparation can result in DNA template loss and sequencing biases, affecting downstream analyses. The development of library preparation methods that circumvent...... preparation time and expenses. The methods are tested on grey wolf (Canis lupus) museum specimens. 3.We found single-tube protocols increase library complexity, yield more reads that map uniquely to the reference genome, reduce processing time, and may decrease laboratory costs by 90%. 4.Given the advantages...

Growth of ZrSiO4 single crystal by flux method

International Nuclear Information System (INIS)

Ushio, Masumi; Nishitani, Yoshinari

1982-01-01

ZrSiO 4 single crystals were grown from the Na 2 O.3 V 2 O 5 fluxed melt at constant soaking temperatures of 900 0 C and 1000 0 C for periods up to 1710h, using the natural zircon seeds. Temperature difference between the seed and nutrient was 0.5 -- 5 0 C. A solubility curve of the natural zircon in Na 2 O.3 V 2 O 5 was determined. It was found that about 5.7g of the natural crystal dissolved in Na 2 O.3 V 2 O 5 in 48h at 1000 0 C and about 7.5g at 1200 0 C. .the maximum growth weight was about 0.35 2 g under conditions of the temperature difference of 2 0 C and the soaking for 1205h at 1000 0 C. The grown crystal was initially bounded with the c-, m-, p-, a-planes and very small planes consisting of the u- and x-, and finally bounded with the m- and p-planes. The observed linear growth rates of planes of ZrSiO 4 single crystals were in the following order:a(100) > c(001) > p(111) > m(110). The growth rates of a- and m-planes were about 5 -- 7 x 10 -4 mm/h and 0.9 -- 1.0 x 10 -4 mm/h, respectively. The growth hillocks of rounded triangular shape and elliptic shape extended to the direction of c-axis, were observed on the p- and m-planes, respectively. The observed step distence of the spiral and the step height were about 0.97 5 μm and 0.17 2 μm, respectively. The observed linear rate of advance of the step on the m-plane was about 0.4 0 -- 1.2 x 10 -8 cm/s. A linear growth rate of the m-plane was then calculated to be 0.2 5 -- 0.7 1 x 10 -4 mm/h by the BCF theory, which agreed in order of magnitude with the observes growth rate of the m-plabe. (author)

The Finite-Surface Method for incompressible flow: a step beyond staggered grid

Science.gov (United States)

Hokpunna, Arpiruk; Misaka, Takashi; Obayashi, Shigeru

2017-11-01

We present a newly developed higher-order finite surface method for the incompressible Navier-Stokes equations (NSE). This method defines the velocities as a surface-averaged value on the surfaces of the pressure cells. Consequently, the mass conservation on the pressure cells becomes an exact equation. The only things left to approximate is the momentum equation and the pressure at the new time step. At certain conditions, the exact mass conservation enables the explicit n-th order accurate NSE solver to be used with the pressure treatment that is two or four order less accurate without loosing the apparent convergence rate. This feature was not possible with finite volume of finite difference methods. We use Fourier analysis with a model spectrum to determine the condition and found that the range covers standard boundary layer flows. The formal convergence and the performance of the proposed scheme is compared with a sixth-order finite volume method. Finally, the accuracy and performance of the method is evaluated in turbulent channel flows. This work is partially funded by a research colloaboration from IFS, Tohoku university and ASEAN+3 funding scheme from CMUIC, Chiang Mai University.

The Theory and Practice of the Six-Step Method in EFL and Its Transferability to Engineering Programmes

Science.gov (United States)

Ntombela, Berrington X. S.

2013-01-01

This paper outlines the theory of the six-step method developed by personnel in the Language and Learning department at Caledonian College of Engineering, Oman. The paper further illustrates the application of this method in teaching Project, Listening, Reading, Writing, and Speaking & Debate at Foundation level. The assumption in applying the…

Atomic-scale friction on stepped surfaces of ionic crystals.

Science.gov (United States)

Steiner, Pascal; Gnecco, Enrico; Krok, Franciszek; Budzioch, Janusz; Walczak, Lukasz; Konior, Jerzy; Szymonski, Marek; Meyer, Ernst

2011-05-06

We report on high-resolution friction force microscopy on a stepped NaCl(001) surface in ultrahigh vacuum. The measurements were performed on single cleavage step edges. When blunt tips are used, friction is found to increase while scanning both up and down a step edge. With atomically sharp tips, friction still increases upwards, but it decreases and even changes sign downwards. Our observations extend previous results obtained without resolving atomic features and are associated with the competition between the Schwöbel barrier and the asymmetric potential well accompanying the step edges.

Electric-current-induced step bunching on Si(111)

International Nuclear Information System (INIS)

Homma, Yoshikazu; Aizawa, Noriyuki

2000-01-01

We experimentally investigated step bunching induced by direct current on vicinal Si(111)'1x1' surfaces using scanning electron microscopy and atomic force microscopy. The scaling relation between the average step spacing l b and the number of steps N in a bunch, l b ∼N -α , was determined for four step-bunching temperature regimes above the 7x7-'1x1' transition temperature. The step-bunching rate and scaling exponent differ between neighboring step-bunching regimes. The exponent α is 0.7 for the two regimes where the step-down current induces step bunching (860-960 and 1210-1300 deg. C), and 0.6 for the two regimes where the step-up current induces step bunching (1060-1190 and >1320 deg. C). The number of single steps on terraces also differs in each of the four temperature regimes. For temperatures higher than 1280 deg. C, the prefactor of the scaling relation increases, indicating an increase in step-step repulsion. The scaling exponents obtained agree reasonably well with those predicted by theoretical models. However, they give unrealistic values for the effective charges of adatoms for step-up-current-induced step bunching when the 'transparent' step model is used

Principles of crystallization, and methods of single crystal growth

International Nuclear Information System (INIS)

Chacra, T.

2010-01-01

Most of single crystals (monocrystals), have distinguished optical, electrical, or magnetic properties, which make from single crystals, key elements in most of technical modern devices, as they may be used as lenses, Prisms, or grating sin optical devises, or Filters in X-Ray and spectrographic devices, or conductors and semiconductors in electronic, and computer industries. Furthermore, Single crystals are used in transducer devices. Moreover, they are indispensable elements in Laser and Maser emission technology.Crystal Growth Technology (CGT), has started, and developed in the international Universities and scientific institutions, aiming at some of single crystals, which may have significant properties and industrial applications, that can attract the attention of international crystal growth centers, to adopt the industrial production and marketing of such crystals. Unfortunately, Arab universities generally, and Syrian universities specifically, do not give even the minimum interest, to this field of Science.The purpose of this work is to attract the attention of Crystallographers, Physicists and Chemists in the Arab universities and research centers to the importance of crystal growth, and to work on, in the first stage to establish simple, uncomplicated laboratories for the growth of single crystal. Such laboratories can be supplied with equipment, which are partly available or can be manufactured in the local market. Many references (Articles, Papers, Diagrams, etc..) has been studied, to conclude the most important theoretical principles of Phase transitions,especially of crystallization. The conclusions of this study, are summarized in three Principles; Thermodynamic-, Morphologic-, and Kinetic-Principles. The study is completed by a brief description of the main single crystal growth methods with sketches, of equipment used in each method, which can be considered as primary designs for the equipment, of a new crystal growth laboratory. (author)

Single-mismatch 2LSB embedding method of steganography

OpenAIRE

Khalind, Omed; Aziz, Benjamin

2013-01-01

This paper proposes a new method of 2LSB embedding steganography in still images. The proposed method considers a single mismatch in each 2LSB embedding between the 2LSB of the pixel value and the 2-bits of the secret message, while the 2LSB replacement overwrites the 2LSB of the image’s pixel value with 2-bits of the secret message. The number of bit-changes needed for the proposed method is 0.375 bits from the 2LSBs of the cover image, and is much less than the 2LSB replacement which is 0.5...

Single Camera Calibration in 3D Vision

Directory of Open Access Journals (Sweden)

Caius SULIMAN

2009-12-01

Full Text Available Camera calibration is a necessary step in 3D vision in order to extract metric information from 2D images. A camera is considered to be calibrated when the parameters of the camera are known (i.e. principal distance, lens distorsion, focal length etc.. In this paper we deal with a single camera calibration method and with the help of this method we try to find the intrinsic and extrinsic camera parameters. The method was implemented with succes in the programming and simulation environment Matlab.

Step responses of a torsional system with multiple clearances: Study of vibro-impact phenomenon using experimental and computational methods

Science.gov (United States)

Oruganti, Pradeep Sharma; Krak, Michael D.; Singh, Rajendra

2018-01-01

Recently Krak and Singh (2017) proposed a scientific experiment that examined vibro-impacts in a torsional system under a step down excitation and provided preliminary measurements and limited non-linear model studies. A major goal of this article is to extend the prior work with a focus on the examination of vibro-impact phenomena observed under step responses in a torsional system with one, two or three controlled clearances. First, new measurements are made at several locations with a higher sampling frequency. Measured angular accelerations are examined in both time and time-frequency domains. Minimal order non-linear models of the experiment are successfully constructed, using piecewise linear stiffness and Coulomb friction elements; eight cases of the generic system are examined though only three are experimentally studied. Measured and predicted responses for single and dual clearance configurations exhibit double sided impacts and time varying periods suggest softening trends under the step down torque. Non-linear models are experimentally validated by comparing results with new measurements and with those previously reported. Several metrics are utilized to quantify and compare the measured and predicted responses (including peak to peak accelerations). Eigensolutions and step responses of the corresponding linearized models are utilized to better understand the nature of the non-linear dynamic system. Finally, the effect of step amplitude on the non-linear responses is examined for several configurations, and hardening trends are observed in the torsional system with three clearances.

METHOD FOR MANUFACTURING A SINGLE CRYSTAL NANO-WIRE