Beneficiation and leaching study of a muti-Au carrier and low grade refractory gold ore

NASA Astrophysics Data System (ADS)

Li, W. J.; Song, Y. S.; Chen, Y.; Cai, L. L.; Zhou, G. Y.

2017-09-01

Detailed mineralogy and beneficiation and leaching study of a muti-Au carrier, low grade refractory gold ore from a beneficiation plant in Henan Province, China, was investigated. Mineral liberation analysis, scanning electron microscopy, element phase analysis and etc. by a mineral liberation analyser were used for mineralogical characterization study of this ore. The present work describes an experimental study on the effect of traditional parameters (such as grinding fineness and reagent regimes), middling processing method and flowsheet construction on the total recovery and the assay of the floatation concentrate. Two-step floatation and part of middling combined to the floatation tailing for gold leaching process resulted in high gold grade (g.t-1) and gold recovery (%) for this refractory gold ore. This process opens the possibilities of maximizing Au grade and recoveries in a muti-Au carrier and low grade refractory gold ore where low recoveries are common.

Ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction for the separation and determination of estrogens in water samples by high-performance liquid chromatography with fluorescence detection.

PubMed

Zhang, Rui; Wang, Chuanliu; Yue, Qiaohong; Zhou, Tiecheng; Li, Na; Zhang, Hanqi; Hao, Xiaoke

2014-11-01

An ionic liquid foam floatation coupled with ionic liquid dispersive liquid-liquid microextraction method was proposed for the extraction and concentration of 17-α-estradiol, 17-β-estradiol-benzoate, and quinestrol in environmental water samples by high-performance liquid chromatography with fluorescence detection. 1-Hexyl-3-methylimidazolium tetrafluoroborate was applied as foaming agent in the foam flotation process and dispersive solvent in microextraction. The introduction of the ion-pairing and salting-out agent NH4 PF6 was beneficial to the improvement of recoveries for the hydrophobic ionic liquid phase and analytes. Parameters of the proposed method including concentration of 1-hexyl-3-methylimidazolium tetrafluoroborate, flow rate of carrier gas, floatation time, types and concentration of ionic liquids, salt concentration in samples, extraction time, and centrifugation time were evaluated. The recoveries were between 98 and 105% with relative standard deviations lower than 7% for lake water and well water samples. The isolation of the target compounds from the water was found to be efficient, and the enrichment factors ranged from 4445 to 4632. This developing method is free of volatile organic solvents compared with regular extraction. Based on the unique properties of ionic liquids, the application of foam floatation, and dispersive liquid-liquid microextraction was widened. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reducing iliotibial band contractures in patients with muscular dystrophy using custom dry floatation cushions.

PubMed

Wong, C K; Wade, C K

1995-07-01

Custom dry floatation cushions were used to potentially reduce iliotibial band (ITB) contractures in long-term wheelchair users. Time-series with repeated measures pretreatment and posttreatment with follow-up at 6 and 12 months. Community wheelchair users seen in private office. A volunteer sample of nine subjects diagnosed with Duchenne's or limb-girdle muscular dystrophy, nonambulatory at least 3 years, and able to lie prone were included. One subject dropped out owing to adverse effects, one for technical reasons. Seven subjects completed the study and were contacted 6 months later; two were evaluated 1 year later. The participants ranged in age from 9 to 69 years, were nonambulatory an average of 7 years, and spent 12 to 16 hours a day in their wheelchairs. Subjects used custom dry floatation (ROHO) wheelchair cushions for 9 weeks. The cushions were designed with a sunken middle portion and separately inflated lateral portions, providing adduction to the thighs. ITB contractures were measured using goniometry every 3 weeks, twice before and three times after cushion delivery. After 9 weeks, a 13 degrees average decrease in ITB contracture was noted, representing a 34% change from baseline (p < .001, 99% confidence intervals, paired one-tailed t test). Using a custom dry floatation cushion for 9 weeks reduced ITB contractures in nonambulatory muscular dystrophy patients by an average 34%. Patients with large initial ITB contractures benefited the most. Such a cushion could be used to reduce ITB contractures in similar patient populations.

The basic aerodynamics of floatation

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

Davies, M.J.; Wood, D.H.

1983-09-01

The original derivation of the basic theory governing the aerodynamics of both hovercraft and modern floatation ovens, requires the validity of some extremely crude assumptions. However, the basic theory is surprisingly accurate. It is shown that this accuracy occurs because the final expression of the basic theory can be derived by approximating the full Navier-Stokes equations in a manner that clearly shows the limitations of the theory. These limitations are used in discussing the relatively small discrepancies between the theory and experiment, which may not be significant for practical purposes.

Water turbine system and method of operation

DOEpatents

Costin, Daniel P [Montpelier, VT

2011-05-10

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Water turbine system and method of operation

DOEpatents

Costin, Daniel P [Montpelier, VT

2009-02-10

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Water turbine system and method of operation

DOEpatents

Costin, Daniel P.

2010-06-15

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Zero-order delivery of a highly soluble, low dose drug alfuzosin hydrochloride via gastro-retentive system.

PubMed

Liu, Quan; Fassihi, Reza

2008-02-04

A composite gastro-retentive matrix for zero-order delivery of highly soluble drug alfuzosin hydrochloride (10mg) has been designed and characterized. Two systems containing polyethylene oxide (PEO), hydroxypropylmethylcellulose (HPMC), sodium bicarbonate, citric acid and polyvinyl pyrrolidone were dry blended and compressed into triple layer and bi-layer composite matrices. Dissolution studies using the USP 27 paddle method at 100 and 50rpm in pH 2.0 and 6.8 were performed using UV spectroscopy at 244nm, with automatic sampling over a 24h period using a marketed product as a reference to calculate the "f(2)" factor. Textural characteristics of each layer, the composite matrix as a whole, and floatation potential were determined under conditions similar to dissolution. Percent matrix swelling and erosion along with digital images were also obtained. Both systems proved to be effective in providing prolonged floatation, zero-order release, and complete disentanglement and erosion based on the analysis of data with "f(2)" of 68 and 71 for PEO and HPMC based systems, respectively. The kinetics of drug release, swelling and erosion, and dynamics of textural changes during dissolution for the designed composite systems offer a novel approach for developing gastro-retentive drug delivery system that has potential to enhance bioavailability and site-specific delivery to the proximal small intestine.

The method for froth floatation condition recognition based on adaptive feature weighted

NASA Astrophysics Data System (ADS)

Wang, Jieran; Zhang, Jun; Tian, Jinwen; Zhang, Daimeng; Liu, Xiaomao

2018-03-01

The fusion of foam characteristics can play a complementary role in expressing the content of foam image. The weight of foam characteristics is the key to make full use of the relationship between the different features. In this paper, an Adaptive Feature Weighted Method For Froth Floatation Condition Recognition is proposed. Foam features without and with weights are both classified by using support vector machine (SVM).The classification accuracy and optimal equaling algorithm under the each ore grade are regarded as the result of the adaptive feature weighting algorithm. At the same time the effectiveness of adaptive weighted method is demonstrated.

Ionic liquid foam floatation coupled with solid phase extraction for separation and determination of hormones by high-performance liquid chromatography.

PubMed

Zhang, Rui; Li, Na; Wang, Chuanliu; Bai, Yuping; Ren, Ruibing; Gao, Shiqian; Yu, Wenzhi; Zhao, Tianqi; Zhang, Hanqi

2011-10-17

The foaming property of ionic liquids (ILs) was found and the factors that can influence foamability of the ILs were investigated. Based on the property of the ILs, the foam floatation-solid phase extraction (FF-SPE) was developed. The IL-based FF-SPE was applied to the extraction and concentration of steroid hormones, including corticosterone, 17-β-estadiol, 17-α-estradiol, 19-nortestosterone, estrone, testosterone, 17-α-hydroxyprogesterone, medroxyprogesterone, chloromadinon 17-acetate, norethisterone acetate, medroxyprogesterone-17-acetate, progesterone, 17-β-estradiol 3-benzoate and testosteron 17-propionate in water samples and then the steroid hormones were determined by high-performance liquid chromatography. The extraction and concentration were performed synchronously in 10 min. Some experimental conditions were examined and optimized. The recoveries ranged from 50.6% to 95.2% for lake water sample and from 53.4% to 98.7% for rain water sample. The precision ranged from 2.43% to 7.43% for the lake water sample and 2.07-7.01% for rain water sample. Based on the foaming property of ILs, the application of foam floatation should be widened. Copyright © 2011 Elsevier B.V. All rights reserved.

Floating drug delivery systems: a review.

PubMed

Arora, Shweta; Ali, Javed; Ahuja, Alka; Khar, Roop K; Baboota, Sanjula

2005-10-19

The purpose of writing this review on floating drug delivery systems (FDDS) was to compile the recent literature with special focus on the principal mechanism of floatation to achieve gastric retention. The recent developments of FDDS including the physiological and formulation variables affecting gastric retention, approaches to design single-unit and multiple-unit floating systems, and their classification and formulation aspects are covered in detail. This review also summarizes the in vitro techniques, in vivo studies to evaluate the performance and application of floating systems, and applications of these systems. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.

Astrobiological relevance and feasibility of a sample collection mission to the atmosphere of Venus

NASA Astrophysics Data System (ADS)

Schulze-Makuch, Dirk; Irwin, Louis N.; Irwin, Troy

2002-11-01

The lower cloud level of the Venusian atmosphere is an environmental niche that could harbor microbial life. Particularly the mode 3 particles that are enriched in this atmospheric layer are of astrobiological interest. We propose here a sample collection mission to the atmosphere of Venus and evaluate three mission options. The first option is a Stardust-type spacecraft used for sample collection, the second option is a Rotating Probe Tether System, and the third option is a Parachute Drop - Balloon Floatation System. Given the current state of technology, the result of our preliminary analysis is that the Parachute Drop - Balloon Floatation Mission is the most feasible and practical option.

Wheelchair cushion effect on skin temperature, heat flux, and relative humidity.

PubMed

Stewart, S F; Palmieri, V; Cochran, G V

1980-05-01

For patients subject to decubitus ulcers, wheelchair cushions should be prescribed with knowledge of the cushion's effect on the thermal as well as mechanical environment of the skin. To define thermal effects that may be encountered during routine use, tests werr made on 24 commercially available cushions. Skin temperature, heat flux and relative humidity were measured under the ischial tuberosities of a normal 24-year-old man during a 1-hour period of sitting on each cushion. After 1 hour, skin temperatures increased by means of 3.4 C and 2.8 C on foams and viscoelastic foams and there were slight decreases in heat flux as compared with control values in air. On gels, skin temperatures remained constant and heat flux increased, while water "floatation" pads caused a mean skin temperature decreased of 2.7 C along with a marked increase in heat flux. Relative humidity at the skin cushion interface increased by 10.4%, 22.8% and 19.8% on foams, gels and water floatation pads, as compared with room air values. Representative cushions from each of the general types (foam, viscoelastic foam, gel and water floatation) also were subjected to 2-hour tests which indicated the measured parameters continued to change asymptotically.

Intermediate eXperimental Vehicle Jettison Mechanism Engineering and Test

NASA Astrophysics Data System (ADS)

Caldirola, L.; Schmid, B.

2015-09-01

The IXV (Intermediate eXperimental Vehicle) is a project of the European Space Agency that aims to develop an autonomous atmospheric re-entry system. A flight model has been launched on a Vega rocket on the 11th of February 2015 and after descending from an altitude of 420km splashed down in the Pacific Ocean. In the frame of this project RUAG space has developed the entire cold structure and the mechanisms able to eject the panels closing the parachute and floatation balloons bays. Panels ejection allows respectively parachutes deployment, reducing the IXV re-entry speed from Mach 1.5 to few meters per second just before the splash down, and buoyancy balloons inflation which let the vehicle float on the sea surface until arrival of the recovery ship.Such panels and the relevant mechanisms had to be designed not only to guarantee the correct external aerodynamic shape needed for the flight performance, but also to provide enough stiffness and strength to the IXV structure, being capable of transfer high shear loads.Moreover the floatation doors design enclosed both the hold down and release mechanism, based on a non- explosive separation nut, and the jettison springs, therefore particular attention had to be put to prevent any damage to the panel during the release which could have potentially led to jamming of the panel itself which jeopardise the floatation balloon deployment. The chosen design was therefore based on a spherical joint, so that shear load can be withstand and bending moment on the jettison-able panels limited at the same time.Test activities have been performed at mechanism level for environmental and preliminary functional qualification, subsystem level, including dummy panel jettison and full scale IXV drop test, to complete the functional qualification and system level test to close qualification campaign.The purpose of this paper is to present the mechanism design and the activities performed to qualify at component and sub-system level the jettison mechanism of the floatation balloons doors.

Application of Mössbauer spectroscopy for: (1) characterization of Egyptian Maghara coal; (2) evaluating the efficiency of different methods for coal desulphurization

NASA Astrophysics Data System (ADS)

Eissa, N. A.; Sheta, N. H.; Ahmed, M. A.

1992-04-01

Coal has been recently discovered in Maghara mine at Northern Sinai, Egypt. Coal samples have been collected from different depths and were measured by XRD, XRF, and MS, in order to characterize this type of coal. It has been found that the iron bearing minerals are mainly pyrite and different sulphates depending on the depth of the sample. The second part contains the application of desulphurization techniques to Egyptian coal which are: floatation (one step and two steps) chemical [(HCl+HNO3), and Fe2(SO4)3] and bacterial methods (Chromatium and Chlorobium species). The efficiency of each technique was calculated. A comparative discussion is given of each desulphurization method, from which the bacterial method has proved to be the most efficient one.

Parasitic contamination of vegetables in Jos, Nigeria.

PubMed

Damen, J G; Banwat, E B; Egah, D Z; Allanana, J A

2007-09-01

Intestinal parasites are very common in developing countries including Nigeria. There are diverse ways of their transmission; the study attempts to determine the level of intestinal parasitic contamination on vegetables sold in Jos. Sample of 200 each of Tomatoes (Lycopersium sativus), Letus (Loctus satival) Carrot (Davcus carota L) Cabbage (Brassica Denceal) and Green leafy vegetables were analyzed using standardized Centrifugal-floatation technique methods. Of the 1250 samples of vegetables examined, 450 (36.0%) were positive for intestinal parasites, cabbage recorded the highest prevalence of 64% while tomatoes had the least prevalence of 20%. Vegetables in Jos are heavily contaminated with intestinal parasites and there is need for public enlightenment campaign on the danger of consuming inadequately washed and prepared vegetables.

Percutaneous treatment of Lutembacher syndrome in a case with difficult mitral valve crossing.

PubMed

Bhambhani, Anupam; Somanath, H S

2012-03-01

Most cases of combination congenital cardiac anomalies are treated with open-heart surgeries because the coexisting anomalies change the cardiac anatomy in an adverse way, making catheter manipulations complex. Lutembacher syndrome is a combination of acquired mitral stenosis and congenital ostium secundum atrial septal defect. The large defect in the septum makes an Inoue balloon catheter unstable, which provides excessive space for free floatation of the catheter, making its passage into the left ventricle difficult by Inoue technique. We present a case of elective definitive percutaneous treatment of Lutembacher syndrome, discussing the technical difficulties faced in mitral valve crossing and reviewing the possible strategies to improve chances of success.

A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

NASA Technical Reports Server (NTRS)

Williams, R. J.

1986-01-01

The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or floatation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacites with small quantities of gas which are recirculated over the sample is described. This system should be adaptable to reduced gravity space experiments requiring redox control. Experiments done conventionally and those done using this technique yield identical results done in a 1-g field.

A simple method for the extraction and identification of light density microplastics from soil.

PubMed

Zhang, Shaoliang; Yang, Xiaomei; Gertsen, Hennie; Peters, Piet; Salánki, Tamás; Geissen, Violette

2018-03-01

This article introduces a simple and cost-saving method developed to extract, distinguish and quantify light density microplastics of polyethylene (PE) and polypropylene (PP) in soil. A floatation method using distilled water was used to extract the light density microplastics from soil samples. Microplastics and impurities were identified using a heating method (3-5s at 130°C). The number and size of particles were determined using a camera (Leica DFC 425) connected to a microscope (Leica wild M3C, Type S, simple light, 6.4×). Quantification of the microplastics was conducted using a developed model. Results showed that the floatation method was effective in extracting microplastics from soils, with recovery rates of approximately 90%. After being exposed to heat, the microplastics in the soil samples melted and were transformed into circular transparent particles while other impurities, such as organic matter and silicates were not changed by the heat. Regression analysis of microplastics weight and particle volume (a calculation based on image J software analysis) after heating showed the best fit (y=1.14x+0.46, R 2 =99%, p<0.001). Recovery rates based on the empirical model method were >80%. Results from field samples collected from North-western China prove that our method of repetitive floatation and heating can be used to extract, distinguish and quantify light density polyethylene microplastics in soils. Microplastics mass can be evaluated using the empirical model. Copyright © 2017 Elsevier B.V. All rights reserved.

Tapioca starch graft copolymers and Dome Matrix® modules II. Effect of modules assemblage on riboflavin release kinetics.

PubMed

Casas, Marta; Strusi, Orazio Luca; Jiménez-Castellanos, M Rosa; Colombo, Paolo

2011-01-01

This paper studies the Riboflavin release from systems made of assembled modules of Dome Matrix® technology using tapioca starch-ethylmethacrylate (TSEMA) and tapioca hydroxypropylstarch-ethylmethacrylate (THSEMA) graft copolymers produced by two different drying methods. Two different shape modules were manufactured for this study, i.e., female and male modules, in order to facilitate their assemblage in "void configuration", a system with an internal void space. Drug release studies on void configurations based on THSEMA show faster releases than TSEMA; HPMC systems used as a comparative reference showed intermediate release. Moreover, using void configurations made with one module of TSEMA and the other of THSEMA is possible to average the drug release, without difference between the drying methods used for the polymers. With respect to the floatation characteristics, all the void configurations floated immediately and, due to the mass center of the system, the floatation position of the system was always axial with the female module up and the male down. The drug release studies performed with a sinker to force the immersion of the systems in the medium did not show differences with respect to the dissolution test without a sinker. The combination of floatation capability of the assembled modules and the prolonged drug release provided with the graft copolymers make these assembled modules candidates as controlled release gastro-retentive dosage forms. Copyright © 2010 Elsevier B.V. All rights reserved.

Closeup View - Sigma "7" Capsule - Recovery Ship

NASA Image and Video Library

1962-10-03

S62-06175 (3 Oct. 1962) --- Closeup view of the Mercury-Atlas 8 (MA-8) Sigma 7 capsule being lowered to recovery ship's deck. Navy personnel remove the floatation device before opening the capsule. Photo credit: NASA

Recovery of Copper from Slow Cooled Ausmelt Furnace Slag by Floatation

NASA Astrophysics Data System (ADS)

Xue, Ping; Li, Guangqiang; Qin, Qingwei

Ausmelt furnace slag contains about 0.9% Cu (mass %). With increasing the amount of Ausmelt furnace slag, the recovery of copper from it will produce an enormous economic yield. The recovery of copper by floatation from slow cooled Ausmelt furnace slag was studied in this paper. The phases and composition of the slow cooled slag were analyzed. The factors which affected the copper recovery efficiency such as grinding fineness, pH value of flotation medium, different collectors and floating process were investigated. It was shown that the size distribution of the primary grinding and secondary grinding of middling were 75% for particles less than 0.074mm and 82% for particles less than 0.043mm respectively. The closed-circuit experimental results with butyl xanthate as collector in laboratory showed that the copper grade reached 16.11% and the recovery rate of copper reached 69.90% and the copper grade of tailings was only 0.2%.

Association between wearing a personal floatation device and death by drowning among recreational boaters: a matched cohort analysis of United States Coast Guard data.

PubMed

Cummings, P; Mueller, B A; Quan, L

2011-06-01

To estimate the association between wearing a personal floatation device (PFD) and death by drowning among recreational boaters. Matched cohort study analysis of Coast Guard data. United States. Recreational boaters during 2000-2006. Risk ratio (RR) for drowning death comparing boaters wearing a PFD with boaters not wearing a PFD. Approximately 4915 boater records from 1809 vessels may have been eligible for our study, but because of missing records and other problems, the analysis was restricted to 1597 boaters in 625 vessels with 878 drowning deaths. The adjusted RR was 0.51 (95% CI 0.35 to 0.74). If the estimated association is causal, wearing a PFD may potentially prevent one in two drowning deaths among recreational boaters. However, this estimate may be biased because many vessels had to be excluded from the analysis.

29 CFR 1915.158 - Lifesaving equipment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Personal Protective Equipment (PPE) § 1915.158 Lifesaving equipment. (a) Personal flotation devices. (1) PFDs (life preservers, life... Equipment Specifications. (2) Prior to each use, personal floatation devices shall be inspected for dry rot...

29 CFR 1915.158 - Lifesaving equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Personal Protective Equipment (PPE) § 1915.158 Lifesaving equipment. (a) Personal flotation devices. (1) PFDs (life preservers, life... Equipment Specifications. (2) Prior to each use, personal floatation devices shall be inspected for dry rot...

Pascal's Snowshoes

ERIC Educational Resources Information Center

Akcay, Behiye

2004-01-01

The chief purpose of this activity is to strengthen students' understanding of concepts of floatation such as surface area and pressure (weight per unit area) via snowshoes. Students brainstorm, make predictions, perform calculations, and practice communication skills through interviewing elders and experts. This activity lets students see the…

Prevalence and risk factors of Echinococcus granulosus infection in dogs in Moroto and Bukedea districts in Uganda.

PubMed

Oba, Peter; Ejobi, Francis; Omadang, Leonard; Chamai, Martin; Okwi, Andrew Livex; Othieno, Emmanuel; Inangolet, Francis Olaki; Ocaido, Michael

2016-02-01

A cross sectional study was conducted in Moroto and Bukedea districts of Uganda from May to September 2013 to determine the prevalence and risk factors of Echinococcus granulosus infection in dogs. Fresh dog faecal samples were collected, preserved in 70 % ethanol, and later screened for presence of taeniid eggs using zinc chloride floatation method. Positive samples were confirmed by a copro-PCR (polymerase chain reaction) for E. granulosus using NADH dehydrogenase sub-unit 1 gene (NADH1) as a target molecular marker. Structured questionnaires and focus group discussions were used to collect quantitative and qualitative data for risk factor identification. Study sub-counties were selected by simple random sampling. Overall apparent prevalence of taeniid infection in dogs of 14.9 % (39/261, confidence interval 10.6-19.2) in both districts was recorded using the faecal floatation test. The sensitivity of the faecal floatation test was found to be 78 % (25/32), while the specificity was 93 % (215/229). Copro-PCR results revealed a true prevalence of 14.4 % (9.91-19.0, 95 % CI) in dogs in Moroto district and 7.4 % (2.14-12.60, 95 % CI) in Bukedea district. The overall true prevalence of cystic echinococcosis (CE) was 12.2 % (8.70-15.76, 95 % CI) in both districts. The major risk factors identified using logistic regression were uncontrolled access of dogs to animal slaughter facilities, higher cattle herd sizes and lack of knowledge about the disease. It was recommended that restricting dog access to infected tissues and public health education about epidemiology of CE should be done.

Risk assessment of false-positive quantitative real-time PCR results in food, due to detection of DNA originating from dead cells.

PubMed

Wolffs, Petra; Norling, Börje; Rådström, Peter

2005-03-01

Real-time PCR technology is increasingly used for detection and quantification of pathogens in food samples. A main disadvantage of nucleic acid detection is the inability to distinguish between signals originating from viable cells and DNA released from dead cells. In order to gain knowledge concerning risks of false-positive results due to detection of DNA originating from dead cells, quantitative PCR (qPCR) was used to investigate the degradation kinetics of free DNA in four types of meat samples. Results showed that the fastest degradation rate was observed (1 log unit per 0.5 h) in chicken homogenate, whereas the slowest rate was observed in pork rinse (1 log unit per 120.5 h). Overall results indicated that degradation occurred faster in chicken samples than in pork samples and faster at higher temperatures. Based on these results, it was concluded that, especially in pork samples, there is a risk of false-positive PCR results. This was confirmed in a quantitative study on cell death and signal persistence over a period of 28 days, employing three different methods, i.e. viable counts, direct qPCR, and finally floatation, a recently developed discontinuous density centrifugation method, followed by qPCR. Results showed that direct qPCR resulted in an overestimation of up to 10 times of the amount of cells in the samples compared to viable counts, due to detection of DNA from dead cells. However, after using floatation prior to qPCR, results resembled the viable count data. This indicates that by using of floatation as a sample treatment step prior to qPCR, the risk of false-positive PCR results due to detection of dead cells, can be minimized.

Evaluation of a spot-on imidacloprid-moxidectin formulation (Advocate®) for the treatment of naturally occurring esophageal spirocercosis in dogs: a double-blinded, placebo-controlled study.

PubMed

Segev, Gilad; Rojas, Alicia; Lavy, Eran; Yaffe, Marganit; Aroch, Itamar; Baneth, Gad

2018-03-05

Dogs are the definitive hosts of Spirocerca lupi. Spirocercosis is treated by prolonged avermectin administration by injection or daily oral doses. In this prospective, double-blinded, placebo-controlled, clinical trial, the efficacy of imidacloprid and moxidectin spot-on formulation (Advocate®) was compared to injectable doramectin (Dectomax®). Dogs diagnosed with benign esophageal spirocercosis were divided randomly into doramectin (400 μg/kg IM) or moxidectin and imidacloprid spot-on (2.5-6.25 mg/kg and 10-25 mg/kg, respectively) groups and treated weekly for 12 consecutive weeks. Dogs were followed for 20 weeks by physical examination, owners' questionnaire, blood work, fecal floatation, PCR and endoscopy. All the doramectin group dogs (n = 10) completed the treatment and follow-up, and the disease had completely resolved in all by week 12. Of the Advocate® group (n = 10), four had complete resolution at week 12, four had partial resolution, one dog did not respond to treatment, and one dog was switched to the doramectin protocol on week 5 due to persistent severe clinical signs. PCR analysis was more sensitive in detecting S. lupi eggs compared to fecal floatation. Discrepancies were detected on 22 occasions, of which on 20 occasions, the PCR was positive while fecal floatation was negative, and only on two occasions the PCR results were negative while fecal flotation was positive. The present results indicate that weekly Advocate® spot-on administration may be effective for treating benign esophageal spirocercosis, but is less effective than the currently used injectable doramectin therapy at the dose and duration used herein.

24 CFR 3285.302 - Flood hazard areas.

Code of Federal Regulations, 2010 CFR

2010-04-01

... loads associated with design flood and wind events or combined wind and flood events, and homes must be installed on foundation supports that are designed and anchored to prevent floatation, collapse, or lateral... URBAN DEVELOPMENT MODEL MANUFACTURED HOME INSTALLATION STANDARDS Foundations § 3285.302 Flood hazard...

36 CFR 3.7 - What are the NPS Personal Floatation Device (PFD) requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.7 What are the NPS Personal... designated times and/or during designated water based activities in accordance with §§ 1.5 and 1.7 of this...

36 CFR 3.7 - What are the NPS Personal Floatation Device (PFD) requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.7 What are the NPS Personal... designated times and/or during designated water based activities in accordance with §§ 1.5 and 1.7 of this...

Maintenance Manual for the Automated Airdrop Information Retrieval System; Human Factors Database

DTIC Science & Technology

1994-09-01

Sensorimotor Abilities Loss of Cognitive/Perceptual Abilities Treatment drug therapy physical therapy cognitive therapy biofeedback therapy 63 9...Device (AOD) Oxygen System oxygen mask oxygen hose oxygen cylinders on/off valve prebreather Floatation Devices life preserver Scuba Gear Ankle Braces

Conversion of microalgae to jet fuel: process design and simulation.

PubMed

Wang, Hui-Yuan; Bluck, David; Van Wie, Bernard J

2014-09-01

Microalgae's aquatic, non-edible, highly genetically modifiable nature and fast growth rate are considered ideal for biomass conversion to liquid fuels providing promise for future shortages in fossil fuels and for reducing greenhouse gas and pollutant emissions from combustion. We demonstrate adaptability of PRO/II software by simulating a microalgae photo-bio-reactor and thermolysis with fixed conversion isothermal reactors adding a heat exchanger for thermolysis. We model a cooling tower and gas floatation with zero-duty flash drums adding solids removal for floatation. Properties data are from PRO/II's thermodynamic data manager. Hydrotreating is analyzed within PRO/II's case study option, made subject to Jet B fuel constraints, and we determine an optimal 6.8% bioleum bypass ratio, 230°C hydrotreater temperature, and 20:1 bottoms to overhead distillation ratio. Process economic feasibility occurs if cheap CO2, H2O and nutrient resources are available, along with solar energy and energy from byproduct combustion, and hydrotreater H2 from product reforming. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mechanism of Electro-Coagulation with Al/Fe Periodically Reversing Treating Berberine Pharmaceutical Wastewater

NASA Astrophysics Data System (ADS)

Sun, Zhaonan; Liu, Zheng; Hu, Xiaomin

2017-05-01

The method of treating pharmaceutical wastewater by electro-coagulation with Al/Fe periodically reversing (ECPR) was proposed based on traditional electrochemical method. The principle of ECPR was generalized. Mechanism of ECPR to treat berberine pharmaceutical wastewater was investigated. Treatability and mechanism studies were conducted under laboratory conditions. For berberine wastewater (800 mg/L), decolourization efficiency and COD removal efficiency were highest to 98% and 95% respectively when voltage was 8V, reaction time was 60 min, alternating period was 10 S electrolyte concentration was 0.015 mol/L, stirring speed was 750 rpm, pH value was 3-10 and distance between two plates was 0.6 cm. For removal berberine, flocculation, floatation and oxidation provided 73%, 8% and 18% removal efficiency, which can be inferred by analysing UV-visible absorption spectrum, acidification experiment, EDTA shielding experiment, structure-activity relationship, oxidation and floatation. Meanwhile decolourization and COD removal conformed to apparent pseudo-first order and zero-order kinetics for 200mg/L and 400-1000 mg/L berberine wastewater respectively.

Fracture, inflation and floatation embolisation of PTCA balloon.

PubMed

O'Neill, Louisa; Sowbhaga, Vinay; Owens, Patrick

2015-01-09

This case outlines an unusual complication of coronary intervention, the likely mechanisms leading to this and possible retrieval options. It is the first case to the best of our knowledge reporting this complication. A 78-year-old Caucasian man underwent coronary stenting. During the procedure kinking and subsequent fracture of a non-compliant percutaneous transluminal coronary angioplasty (PTCA) balloon occurred. Injection of contrast down the guide to opacify the coronary arteries resulted in 'inflation' of the balloon with air, and embolisation of the inflated balloon into the proximal left anterior descending artery. The embolised balloon was retrieved by removal of the guide catheter and wire as a unit. The patient had a good angiographic outcome. This case highlights risks associated with usage of kinked balloons catheters, and describes for the first time to our knowledge, the inflation of a PTCA balloon with air from its shaft within the catheter, causing 'floatation' embolisation into the coronary artery. 2015 BMJ Publishing Group Ltd.

Module assemblage technology for floating systems: in vitro flotation and in vivo gastro-retention.

PubMed

Strusi, Orazio Luca; Sonvico, Fabio; Bettini, Ruggero; Santi, Patrizia; Colombo, Gaia; Barata, Pedro; Oliveira, Ana; Santos, Delfim; Colombo, Paolo

2008-07-14

The aim of this research was to study, in vitro by resultant-weight measurement and in vivo by gamma-scintigraphy experiments in humans, the floatation behavior of systems obtained by modules assembled in void configuration. The assembled system technology allowed the manufacturing of a system characterized by the presence of an internal void space that provided an apparent density lower than water. The gastro-retention times of floating assembled systems were determined in comparison with non-floating systems having the same mass and composition. In vitro the floatation of the system started immediately after immersion in water and lasted for more than 5 h. The in vivo studies confirmed that the in vitro floating ability of void configuration was maintained also in the human stomach where the system stayed for periods of time ranging from 2.5 to 5.0 h, depending on the food regimen and the sex of the subject. Reiterate eating and drinking further prolonged the stomach residence time.

46 CFR 197.346 - Diver's equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... communications cable is at least equal to that required for the lifeline, the communications cable can serve as... reserve cylinder connected and ready for use; (2) A face mask; (3) An inflatable floatation device; (4) A... fittings, the control valve, the lifeline, communications cable, and a pneumofathometer; and (4) Be...

78 FR 52407 - Airworthiness Directives; Eurocopter France Helicopters

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

... the flotation gear. (A) Unfold and visually inspect the float assemblies for any cuts, tears... inflating valve and inspect the fabric panels and girts for any cuts, tears, punctures, or abrasion. If there is a cut, tear, puncture, or any abrasion, repair the float. (2) For emergency floatation gear...

Utilization of calcium carbonate particles from eggshell waste as coating pigments for ink-jet printing paper.

PubMed

Yoo, Sukjoon; Hsieh, Jeffery S; Zou, Peter; Kokoszka, John

2009-12-01

The effective treatment and utilization of biowaste have been emphasized in our society for environmental and economic concerns. Recently, the eggshell waste in the poultry industry has been highlighted because of its reclamation potential. This study presents an economical treatment process to recover useful bioproducts from eggshell waste and their utilization in commercial products. We developed the dissolved air floatation (DAF) separation unit, which successfully recovered 96% of eggshell membrane and 99% of eggshell calcium carbonate (ECC) particles from eggshell waste within 2 h of operation. The recovered ECC particles were utilized as coating pigments for ink-jet printing paper and their impact on the ink density and paper gloss were investigated. The addition of the ECC particles as coating pigments enhances the optical density of cyan, magenta and yellow inks while decreasing the black ink density and the gloss of the coated paper.

Protein composition of oil bodies from mature Brassica napus seeds.

PubMed

Jolivet, Pascale; Boulard, Céline; Bellamy, Annick; Larré, Colette; Barre, Marion; Rogniaux, Hélène; d'Andréa, Sabine; Chardot, Thierry; Nesi, Nathalie

2009-06-01

Seed oil bodies (OBs) are intracellular particles storing lipids as food or biofuel reserves in oleaginous plants. Since Brassica napus OBs could be easily contaminated with protein bodies and/or myrosin cells, they must be purified step by step using floatation technique in order to remove non-specifically trapped proteins. An exhaustive description of the protein composition of rapeseed OBs from two double-zero varieties was achieved by a combination of proteomic and genomic tools. Genomic analysis led to the identification of sequences coding for major seed oil body proteins, including 19 oleosins, 5 steroleosins and 9 caleosins. Most of these proteins were also identified through proteomic analysis and displayed a high level of sequence conservation with their Arabidopsis thaliana counterparts. Two rapeseed oleosin orthologs appeared acetylated on their N-terminal alanine residue and both caleosins and steroleosins displayed a low level of phosphorylation.

A small-scale, portable method for extracting microplastics from marine sediments.

PubMed

Coppock, Rachel L; Cole, Matthew; Lindeque, Penelope K; Queirós, Ana M; Galloway, Tamara S

2017-11-01

Microplastics (plastic particles, 0.1 μm-5 mm in size) are widespread marine pollutants, accumulating in benthic sediments and shorelines the world over. To gain a clearer understanding of microplastic availability to marine life, and the risks they pose to the health of benthic communities, ecological processes and food security, it is important to obtain accurate measures of microplastic abundance in marine sediments. To date, methods for extracting microplastics from marine sediments have been disadvantaged by complexity, expense, low extraction efficiencies and incompatibility with very fine sediments. Here we present a new, portable method to separate microplastics from sediments of differing types, using the principle of density floatation. The Sediment-Microplastic Isolation (SMI) unit is a custom-built apparatus which consistently extracted microplastics from sediments in a single step, with a mean efficiency of 95.8% (±SE 1.6%; min 70%, max 100%). Zinc chloride, at a density of 1.5 g cm -3 , was deemed an effective and relatively inexpensive floatation media, allowing fine sediment to settle whilst simultaneously enabling floatation of dense polymers. The method was validated by artificially spiking sediment with low and high density microplastics, and its environmental relevance was further tested by extracting plastics present in natural sediment samples from sites ranging in sediment type; fine silt/clay (mean size 10.25 ± SD 3.02 μm) to coarse sand (mean size 149.3 ± SD 49.9 μm). The method presented here is cheap, reproducible and is easily portable, lending itself for use in the laboratory and in the field, eg. on board research vessels. By employing this method, accurate estimates of microplastic type, distribution and abundance in natural sediments can be achieved, with the potential to further our understanding of the availability of microplastics to benthic organisms. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Transfemoral implantation of an Edwards SAPIEN valve in a tricuspid bioprosthesis without fluoroscopic landmarks.

PubMed

Calvert, Patrick A; Himbert, Dominique; Brochet, Eric; Radu, Costin; Iung, Bernard; Hvass, Ulrik; Darondel, Jean-Marc; Depoix, Jean-Pol; Nataf, Patrick; Vahanian, Alec

2012-03-01

We describe the first report of an Edwards SAPIEN valve implanted in a tricuspid bioprosthesis from the femoral vein. We highlight the feasibility of this previously avoided approach and the techniques involved. A 61-year-old woman with multiple valve replacements for rheumatic heart disease presented with NHYA IV dyspnoea secondary to a severely stenosed tricuspid bioprosthesis. After failed aggressive medical therapy and surgical turn down, an Edwards SAPIEN XT valve was deployed in the tricuspid bioprosthesis via the right femoral vein. Adaptations to the standard transfemoral transcatheter aortic valve implantation (TAVI) technique included: (1) crossing the tricuspid bioprosthesis with a balloon floatation catheter; (2) temporary pacing wire in the coronary sinus rather than the right ventricle; (3) mounting of the SAPIEN XT valve in the reverse orientation to transfemoral TAVI; and (4) fine positioning of the final valve position pre-deployment by 3D transoesophageal echocardiography (3D TOE) alone due to complete radiolucency of the tricuspid bioprosthesis. The procedure was completed without complication and resulted in significant symptomatic improvement. Deployment of an Edwards SAPIEN valve in a tricuspid bioprosthesis via the femoral vein is feasible and, with careful adaptations to established TAVI techniques, can be performed without complications and with good clinical response.

The Molecular Boat: A Hands-On Experiment to Demonstrate the Forces Applied to Self-Assembled Monolayers at Interfaces

ERIC Educational Resources Information Center

Chan, Charlene J.; Salaita, Khalid

2012-01-01

Demonstrating how surface chemistry and self-assembled monolayers (SAMs) control the macroscopic properties of materials is challenging as it often necessitates the use of specialized instrumentation. In this hands-on experiment, students directly measure a macroscopic property, the floatation of glass coverslips on water as a function of…

Automated Airdrop Information Retrieval System-Human Fact ors Database (AAIRS-HFD) (Users Manual)

DTIC Science & Technology

1994-09-01

creeps, or chokes) Pressure Change Disorders Loss of Sensorimotor Abilities Loss of Cognitive/Perceptual Abilities Treatment drug therapy ...physical therapy cognitive therapy biofeedback therapy 73 9. Psychological Factors Situational Awareness altitude awareness Visual/Spatial...on/off valve prebreather Floatation Devices life preserver Scuba Gear Ankle Braces Knee Braces/Pads 82 7. Cargo/Resupply Parachute Assembly

Assessing fullness of asthma patients' aerosol inhalers.

PubMed

Rickenbach, M A; Julious, S A

1994-07-01

The importance of regular medication in order to control asthma symptoms is recognized. However, there is no accurate mechanism for assessing the fullness of aerosol inhalers. The contribution to asthma morbidity of unexpectedly running out of inhaled medication is unknown. A study was undertaken to determine how patients assess inhaler fullness and the accuracy of their assessments, and to evaluate the floatation method of assessing inhaler fullness. An interview survey of 98 patients (51% of those invited to take part), using 289 inhalers, was completed at one general practice in Hampshire. One third of participants said they had difficulty assessing aerosol inhaler fullness and those aged 60 years and over were found to be more inaccurate in assessing fullness than younger participants. Shaking the inhaler to feel the contents move was the commonest method of assessment. When placed in water, an inhaler canister floating on its side with a corner of the canister valve exposed to air indicates that the canister is less than 15% full (sensitivity 90%, specificity 99%). Floating a canister in water provides an objective measurement of aerosol inhaler fullness. Providing the method is recommended by the aerosol inhaler manufacturer, general practitioners should demonstrate the floatation method to patients experiencing difficulty in assessing inhaler fullness.

In vivo anthelmintic efficacy of Aloe ferox, Agave sisalana, and Gunnera perpensa in village chickens naturally infected with Heterakis gallinarum.

PubMed

Mwale, Marizvikuru; Masika, Patrick Julius

2015-01-01

The study was conducted to determine the anthelmintic efficacy of Aloe ferox, Agave sisalana, and Gunnera perpensa against Heterakis gallinarum in village chickens. The chickens naturally infected with H. gallinarum were randomly divided into 14 groups of eight chickens and orally administered distilled water (negative control), mebendazole (positive control), and graded levels (50-, 100-, 200-, and 400-mg/kg doses) of the three plant extracts. At days 0, 7, and 14, the floatation technique was used to determine fecal egg counts and H. gallinarum worms from chicken ceca were counted at days 0 and 14. Egg count reduction percentage (ECR%) was high at day 7 for all the test materials except for A. sisalana (100 mg/kg) that had 33%. At day 14, ECR% was high for all the other test materials save for A. ferox (200 mg/kg), mebendazole, and distilled water which was 50, 32, and 50%, respectively. A. ferox (200 mg/kg), G. perpensa (200 and 400 mg/kg), and A. sisalana (50 and 100 mg/kg) had the highest (85, 78, 74, 86, and 73%, respectively) worm count reduction percentage. The plants had anthelmintic properties. Advocacy and utilization of these plants in improving the health of village chickens could lead to increased productivity, boosting profits for the poultry industry thereby enabling it to meet the supply of animal protein and enhance livelihoods. It is imperative to determine compounds in the crude extracts of these medicinal plants which are responsible for the anthelmintic activities and their mechanism of action.

PROCESS FOR THE CONCENTRATION OF ORES CONTAINING GOLD AND URANIUM

DOEpatents

Gaudin, A.M.; Dasher, J.

1958-06-10

ABS>A process is described for concentrating certain low grade uranium and gold bearing ores, in which the gangue is mainly quartz. The production of the concentrate is accomplished by subjecting the crushed ore to a froth floatation process using a fatty acid as a collector in conjunction with a potassium amyl xanthate collector. Pine oil is used as the frothing agent.

Helminth Infections by Coprological Examination in Sheep-Dogs and Their Zoonotic Importance.

PubMed

Öge, Hatice; Öge, Semih; Özbakış, Gökben; Gürcan, I Safa

2017-03-01

This study was conducted to determine the prevalence of gastrointestinal helminths and diagnose the species of important zoonotic helminths in sheep dogs. Firstly, fecal samples were macroscopically examined; subsequently, formalin-ethyl acetate sedimentation and ZnSO4 centrifugal floatation techniques were applied for the examination of helminth eggs. PCR technique was utilized to determine the species of E. granulosus and T. canis in dogs found positive for Taenia spp. and Toxocara spp. Helminth infection was detected in 35.26% of sheep dogs. Taenia spp. was the most common helminth (12.05%), followed by Toxocara spp. (9.38%), Toxascaris leonina (6.25%), and Trichuris spp. (4.2%). The positive results in the E. granulosus and T. canis-specific PCR-based molecular tests were obtained in 14 of the Taenia egg-positive samples and in 5 of the Toxocara egg-positive samples from dogs. This study has suggested that coprophagy and feed raw offal and meat to dogs may be responsible for finding atypical helminth eggs in fecal samples from dogs in the absence of an actual infection. To make the diagnosis of their owned parasites of dogs, E. granulosus and T. canis which have zoonotic importance, feces must be examined by both conventional and copro-PCR techniques. In addition to dogs' feeding habits, other related factors must be taken into account in the epidemiology of helminth infection; thus, precaution and control measures will be more reliable.

Methods for the preparation of an autologous serum-free cultured epidermis and for autografting applications.

PubMed

Wille, John J; Burdge, Jeremy J; Park, Jong Y

2014-01-01

Cell culture techniques for producing a three-dimensional autologous epidermal autograft (cultured epidermal autograft) suitable for tissue grafting and wound healing procedures are described. This chapter commences with surgical biopsy of patient's skin tissue, further reduction of skin tissues to keratinocyte cells by enzymatic treatment, and recovery of viable adult keratinocytes in a new balanced buffered salt media supportive of the growth of clonally enriched isolated basal keratinocytes. Culture techniques required for the formation of a hole-free monolayer of undifferentiated basal keratinocytes without the use of an organotypic matrix substrate are accomplished with a specially designed nutrient basal media (HECK 109) that is a chemically defined and subsequent culture in this serum-free culture media supplemented with hormones and two human recombinant protein growth factors (EGF and IGF-1). Further culture techniques and media manipulations, including brief exposure to β-TGF to induce reversible G1-phase growth arrest, are followed by para-synchronous induction of a multilayered stratification and keratinizing epidermal differentiation, yielding a living three-dimensional epidermis formed entirely in cell culture. Protocols are listed for its enzymatic removal, floatation, and transfer for shipment to the clinic ready for surgical grafting to the self-same patient's debrided chronic leg ulcers. Recent clinical trial results have demonstrated the utility and efficacy of these grafts in forming durably healed chronic wounds.

Assessing fullness of asthma patients' aerosol inhalers.

PubMed Central

Rickenbach, M A; Julious, S A

1994-01-01

BACKGROUND. The importance of regular medication in order to control asthma symptoms is recognized. However, there is no accurate mechanism for assessing the fullness of aerosol inhalers. The contribution to asthma morbidity of unexpectedly running out of inhaled medication is unknown. AIM. A study was undertaken to determine how patients assess inhaler fullness and the accuracy of their assessments, and to evaluate the floatation method of assessing inhaler fullness. METHOD. An interview survey of 98 patients (51% of those invited to take part), using 289 inhalers, was completed at one general practice in Hampshire. RESULTS. One third of participants said they had difficulty assessing aerosol inhaler fullness and those aged 60 years and over were found to be more inaccurate in assessing fullness than younger participants. Shaking the inhaler to feel the contents move was the commonest method of assessment. When placed in water, an inhaler canister floating on its side with a corner of the canister valve exposed to air indicates that the canister is less than 15% full (sensitivity 90%, specificity 99%). CONCLUSION. Floating a canister in water provides an objective measurement of aerosol inhaler fullness. Providing the method is recommended by the aerosol inhaler manufacturer, general practitioners should demonstrate the floatation method to patients experiencing difficulty in assessing inhaler fullness. PMID:7619099

Floating modular drug delivery systems with buoyancy independent of release mechanisms to sustain amoxicillin and clarithromycin intra-gastric concentrations.

PubMed

Rossi, Alessandra; Conti, Chiara; Colombo, Gaia; Castrati, Luca; Scarpignato, Carmelo; Barata, Pedro; Sandri, Giuseppina; Caramella, Carla; Bettini, Ruggero; Buttini, Francesca; Colombo, Paolo

2016-01-01

Release modules of amoxicillin and clarithromycin combined in a single dosage form designed to float in the gastric content and to sustain the intra-gastric concentrations of these two antibiotics used for the eradication of Helicobacter pylori have been studied. The modules having a disc shape with curved bases were formulated as hydrophilic matrices. Two modules of clarithromycin were assembled by sticking the concave base of one module to the concave base of the other, creating an internal void chamber. The final dosage form was a floating assembly of three modules of clarithromycin and two of amoxicillin in which the drug release mechanism did not interfere with the floatation mechanism. The assembled system showed immediate in vitro floatation at pH 1.2, lasting 5 h. The in vitro antibiotics release profiles from individual modules and assembled systems exhibited linear release rate during buoyancy for at least 8 h. The predicted antibiotic concentrations in the stomach maintained for long time levels significantly higher than the respective minimum inhibitory concentrations (MIC). In addition, an in vivo absorption study performed on beagle dogs confirmed the slow release of clarithromycin and amoxicillin from the assembled system during the assembly's permanence in the stomach for at least 4 h.

Preparation and Elastic Moduli of Germanate Glass Containing Lead and Bismuth

PubMed Central

Sidek, Hj A. A.; Bahari, Hamid R.; Halimah, Mohamed K.; Yunus, Wan M. M.

2012-01-01

This paper reports the rapid melt quenching technique preparation for the new family of bismuth-lead germanate glass (BPG) systems in the form of (GeO2)60–(PbO)40−x–(½Bi2O3)x where x = 0 to 40 mol%. Their densities with respect of Bi2O3 concentration were determined using Archimedes’ method with acetone as a floatation medium. The current experimental data are compared with those of bismuth lead borate (B2O3)20–(PbO)80−x–(Bi2O3)x. The elastic properties of BPG were studied using the ultrasonic pulse-echo technique where both longitudinal and transverse sound wave velocities have been measured in each glass samples at a frequency of 15 MHz and at room temperature. Experimental data shows that all the physical parameters of BPG including density and molar volume, both longitudinal and transverse velocities increase linearly with increasing of Bi2O3 content in the germanate glass network. Their elastic moduli such as longitudinal, shear and Young’s also increase linearly with addition of Bi2O3 but the bulk modulus did not. The Poisson’s ratio and fractal dimensionality are also found to vary linearly with the Bi2O3 concentration. PMID:22606000

Intestinal parasitosis in school children of Lalitpur district of Nepal.

PubMed

Tandukar, Sarmila; Ansari, Shamshul; Adhikari, Nabaraj; Shrestha, Anisha; Gautam, Jyotshana; Sharma, Binita; Rajbhandari, Deepak; Gautam, Shikshya; Nepal, Hari Prasad; Sherchand, Jeevan B

2013-11-09

Enteric parasites are the most common cause of parasitic diseases and cause significant morbidity and mortality, particularly in developing countries like Nepal. The objective of this study was to estimate the prevalence and risk factors of intestinal parasitic infections among school going children of Lalitpur district of Nepal. A total of 1392 stool samples were collected from school children of two government, two private and two community schools of the same district. The stool samples were examined for evidence of parasitic infections by direct microscopy and confirmed by concentration methods (formal ether sedimentation technique or floatation technique by using Sheather's sugar solution). Modified Ziehl-Neelsen (ZN) staining was performed for the detection of coccidian parasites. Prevalence of intestinal parasitosis was found to be 16.7%. The highest prevalence rate was seen with Giardia lamblia (7.4%) followed by Entamoeba histolytica (3.4%) and Cyclospora cayetanensis (1.6%). Children aged 11-15 years and the ones belonging to family of agriculture workers were most commonly affected. Hand washing practice and type of drinking water also showed significant difference. The burden of parasitic infections among the school children, coupled with the poor sanitary conditions in the schools, should be regarded as an issue of public health priority and demands for effective school health programs involving periodic health education and screening.

Preparation and elastic moduli of germanate glass containing lead and bismuth.

PubMed

Sidek, Hj A A; Bahari, Hamid R; Halimah, Mohamed K; Yunus, Wan M M

2012-01-01

This paper reports the rapid melt quenching technique preparation for the new family of bismuth-lead germanate glass (BPG) systems in the form of (GeO(2))(60)-(PbO)(40-) (x)-(½Bi(2)O(3))(x) where x = 0 to 40 mol%. Their densities with respect of Bi(2)O(3) concentration were determined using Archimedes' method with acetone as a floatation medium. The current experimental data are compared with those of bismuth lead borate (B(2)O(3))(20)-(PbO)(80-) (x)-(Bi(2)O(3))(x). The elastic properties of BPG were studied using the ultrasonic pulse-echo technique where both longitudinal and transverse sound wave velocities have been measured in each glass samples at a frequency of 15 MHz and at room temperature. Experimental data shows that all the physical parameters of BPG including density and molar volume, both longitudinal and transverse velocities increase linearly with increasing of Bi(2)O(3) content in the germanate glass network. Their elastic moduli such as longitudinal, shear and Young's also increase linearly with addition of Bi(2)O(3) but the bulk modulus did not. The Poisson's ratio and fractal dimensionality are also found to vary linearly with the Bi(2)O(3) concentration.

Detection of Cryptosporidium and Cyclospora Oocysts from Environmental Water for Drinking and Recreational Activities in Sarawak, Malaysia.

PubMed

Bilung, Lesley Maurice; Tahar, Ahmad Syatir; Yunos, Nur Emyliana; Apun, Kasing; Lim, Yvonne Ai-Lian; Nillian, Elexson; Hashim, Hashimatul Fatma

2017-01-01

Cryptosporidiosis and cyclosporiasis are caused by waterborne coccidian protozoan parasites of the genera Cryptosporidium and Cyclospora, respectively. This study was conducted to detect Cryptosporidium and Cyclospora oocysts from environmental water abstracted by drinking water treatment plants and recreational activities in Sarawak, Malaysia. Water samples (12 each) were collected from Sungai Sarawak Kanan in Bau and Sungai Sarawak Kiri in Batu Kitang, respectively. In addition, 6 water samples each were collected from Ranchan Recreational Park and UNIMAS Lake at Universiti Malaysia Sarawak, Kota Samarahan, respectively. Water physicochemical parameters were also recorded. All samples were concentrated by the iron sulfate flocculation method followed by the sucrose floatation technique. Cryptosporidium and Cyclospora were detected by modified Ziehl-Neelsen technique. Correlation of the parasites distribution with water physicochemical parameters was analysed using bivariate Pearson correlation. Based on the 24 total samples of environmental water abstracted by drinking water treatment plants, all the samples (24/24; 100%) were positive with Cryptosporidium , and only 2 samples (2/24; 8.33%) were positive with Cyclospora . Based on the 12 total samples of water for recreational activities, 4 samples (4/12; 33%) were positive with Cryptosporidium , while 2 samples (2/12; 17%) were positive with Cyclospora . Cryptosporidium oocysts were negatively correlated with dissolved oxygen (DO).

Detection of Cryptosporidium and Cyclospora Oocysts from Environmental Water for Drinking and Recreational Activities in Sarawak, Malaysia

PubMed Central

Tahar, Ahmad Syatir; Yunos, Nur Emyliana; Apun, Kasing; Nillian, Elexson; Hashim, Hashimatul Fatma

2017-01-01

Cryptosporidiosis and cyclosporiasis are caused by waterborne coccidian protozoan parasites of the genera Cryptosporidium and Cyclospora, respectively. This study was conducted to detect Cryptosporidium and Cyclospora oocysts from environmental water abstracted by drinking water treatment plants and recreational activities in Sarawak, Malaysia. Water samples (12 each) were collected from Sungai Sarawak Kanan in Bau and Sungai Sarawak Kiri in Batu Kitang, respectively. In addition, 6 water samples each were collected from Ranchan Recreational Park and UNIMAS Lake at Universiti Malaysia Sarawak, Kota Samarahan, respectively. Water physicochemical parameters were also recorded. All samples were concentrated by the iron sulfate flocculation method followed by the sucrose floatation technique. Cryptosporidium and Cyclospora were detected by modified Ziehl-Neelsen technique. Correlation of the parasites distribution with water physicochemical parameters was analysed using bivariate Pearson correlation. Based on the 24 total samples of environmental water abstracted by drinking water treatment plants, all the samples (24/24; 100%) were positive with Cryptosporidium, and only 2 samples (2/24; 8.33%) were positive with Cyclospora. Based on the 12 total samples of water for recreational activities, 4 samples (4/12; 33%) were positive with Cryptosporidium, while 2 samples (2/12; 17%) were positive with Cyclospora. Cryptosporidium oocysts were negatively correlated with dissolved oxygen (DO). PMID:29234679

Airport cleanup rises above problems

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

Pressly, N.; Lucas, B.; Frumer, B.

Engineers used a treatment combination to improve the in-situ bioremediation system`s efficiency in removing underground fuel leaks at JFK Airport. John F. Kennedy International Airport, in New York City, on Jamaica Bay, has an above-ground storage capacity of about 32 million gallons of jet fuel, which flow through about 50 miles of high-pressure underground pipe to the central terminal area. EAch terminal`s fuel hydrant system was the major source os subsurface contamination at the site. The site is covered by 1 to 1.5 feet of reinforced concrete pavement. Liquid phase jet fuel (free product) was measured on the water tablemore » with true thickness ranging from less than 1 inch to 1 foot. After analysis of core samples, contamination was found adsorbed to the soil with maximum levels at the water table. This article describes the clean up, covering the following topics: microbial conditions during system operation; above-ground treatment challenges: free product emulsification, presence of biomass; evaluation of enhancements: dissolved air floatation, coagulation and flocculation, retention time adjustments; conclusions.« less

Oil-water separation property of polymer-contained wastewater from polymer-flooding oilfields in Bohai Bay, China.

PubMed

Chen, Hua-xing; Tang, Hong-ming; Duan, Ming; Liu, Yi-gang; Liu, Min; Zhao, Feng

2015-01-01

In this study, the effects of gravitational settling time, temperature, speed and time of centrifugation, flocculant type and dosage, bubble size and gas amount were investigated. The results show that the simple increase in settling time and temperature is of no use for oil-water separation of the three wastewater samples. As far as oil-water separation efficiency is concerned, increasing centrifugal speed and centrifugal time is highly effective for L sample, and has a certain effect on J sample, but is not valid for S sample. The flocculants are highly effective for S and L samples, and the oil-water separation efficiency increases with an increase in the concentration of inorganic cationic flocculants. There exist critical reagent concentrations for the organic cationic and the nonionic flocculants, wherein a higher or lower concentration of flocculant would cause a decrease in the treatment efficiency. Flotation is an effective approach for oil-water separation of polymer-contained wastewater from the three oilfields. The oil-water separation efficiency can be enhanced by increasing floatation agent concentration, flotation time and gas amount, and by decreasing bubble size.

[Prevalence of Echinococcus granulosus determined with polymerase chain reaction in dogs in Aydın district].

PubMed

Kuru, Buket Boğa; Aypak, Süleyman; Aysul, Nuran

2013-01-01

In this study, it was aimed to determine the prevalence of E. granulosus in the Aydın district. Clean and fresh faeces samples were collected off the ground from owned dogs (n=100; 25 female, 75 male) with the range of 6-16 months old. These faeces samples were obtained in 13 villages from five different locations (Centre, Söke, Çine, Bozdoğan and Kuyucak) of the Aydın district. The prevalence of E. granulosus was investigated with PCR and prior to applications of molecular techniques, faeces samples were investigated with macroscopic and floatation methods E. granulosus was determined in only one dog (1%; 1/100) and Toxocara canis (11%), Ancylostoma caninum (%3), Taenia spp. (2%) and Capillaria spp. (1%) eggs were also identified. Current prevalence (1%) of E. granulosus in this study is lower than the other studies conducted in different parts of Turkey. Determination of E. granulosus with PCR in faeces without determining any parasites with either macroscopic or microscopic examinations could indicate the potential risk of dog faeces for animal owners, veterinarians and parasitology laboratory technicians.

Eimeria infection in camels (Camelus dromedarius) in Yazd province, central Iran.

PubMed

Sazmand, A; Hamidinejat, H; Hekmatimoghaddam, S; Asadollahi, Z; Mirabdollahi, S

2012-03-01

This study was carried out during the winter of 2008 to the summer 2010 to determine the rate of infection of Eimeria spp. in dromedary camels in Yazd province, Iran at that period. A total of 305 faecal samples were taken per recta from live and slaughtered, apparently healthy camels 9 months to 23 years old. Using saturated zinc sulfate solution floatation technique, samples were prepared and investigated microscopically to detect Eimeria spp. oocysts. Results revealed that the overall frequency of infection in samples was 9.51%. Identified species were Eimeria cameli (47.5%), Eimeria dromedarii (42.5%) and Eimeria bactriani (10%). The rate of infection was higher in the winter season, and in camels aged 5 to 10 years old. Statistical analysis showed that there is a significant difference between infection rate and season, but no effect by age or sex on eimeriosis was found. Since most of the positive cases in our study were adult, our findings suggest that older camels may play an important role in spreading infection as asymptomatic oocyst shedders.

Formulation development of gastroretentive tablets of lamivudine using the floating-bioadhesive potential of optimized polymer blends.

PubMed

Singh, Bhupinder; Garg, Babita; Chaturvedi, Subhash Chand; Arora, Sharry; Mandsaurwale, Rachana; Kapil, Rishi; Singh, Baljinder

2012-05-01

The current studies entail successful formulation of optimized gastroretentive tablets of lamivudine using the floating-bioadhesive potential of carbomers and cellulosic polymers, and their subsequent in-vitro and in-vivo evaluation in animals and humans. Effervescent floating-bioadhesive hydrophilic matrices were prepared and evaluated for in-vitro drug release, floatation and ex-vivo bioadhesive strength. The optimal composition of polymer blends was systematically chosen using central composite design and overlay plots. Pharmacokinetic studies were carried out in rabbits, and various levels of in-vitro/in-vivo correlation (IVIVC) were established. In-vivo gamma scintigraphic studies were performed in human volunteers using (99m) Tc to evaluate formulation retention in the gastric milieu. The optimized formulation exhibited excellent bioadhesive and floatational characteristics besides possessing adequate drug-release control and pharmacokinetic extension of plasma levels. The successful establishment of various levels of IVIVC substantiated the judicious choice of in-vitro dissolution media for simulating the in-vivo conditions. In-vivo gamma scintigraphic studies ratified the gastroretentive characteristics of the optimized formulation with a retention time of 5 h or more. Besides unravelling the polymer synergism, the study helped in developing an optimal once-a-day gastroretentive drug delivery system with improved bioavailability potential exhibiting excellent swelling, floating and bioadhesive characteristics. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

The pulmonary artery catheter: a critical reappraisal.

PubMed

Gidwani, Umesh K; Mohanty, Bibhu; Chatterjee, Kanu

2013-11-01

Balloon floatation pulmonary artery catheters (PACs) have been used for hemodynamic monitoring in cardiac, medical, and surgical intensive care units since the 1970s. With the availability of newer noninvasive diagnostic modalities, particularly echocardiography, the frequency of diagnostic pulmonary artery catheterization has declined. In this review, the evolution of PACs, the results of nonrandomized and randomized studies in various clinical conditions, the uses and abuses of bedside hemodynamic monitoring, and current indications for pulmonary artery catheterization are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Evaluation of secondary protein nutrients as a substitute for soybean meal in diets for beef steers and meat goats.

PubMed

Freeman, S R; Poore, M H; Huntington, G B; Middleton, T F

2008-01-01

Finding appropriate disposal techniques for waste products is one of many challenges facing the poultry-processing industry. One waste generated in significant quantities is dissolved air floatation sludge, a product of wastewater treatment. Converting dissolved air floatation sludge into a dry feed product (meal) for incorporation into livestock feed appears to be a viable solution. This meal, called secondary protein nutrients (SPN), is high in protein (45% CP), fat (28% crude fat), and minerals. The protein consists of 85% B(2) and B(3) fractions, which are moderately to slowly degradable in the rumen, and therefore may potentially escape ruminal degradation and be available for digestion in the lower gastrointestinal tract. The goal of this research was to evaluate SPN as an alternative to traditional protein sources for ruminants by substituting it on an equivalent N basis for soybean meal in cattle and meat goat diets (0, 25, 50, 75, and 100% for cattle; 0, 20, and 40% for goats). When included in corn silage-based steer diets, increasing SPN resulted in linear and quadratic declines in both DMI and ADG (P < 0.001). Dry matter intake diminished with inclusion rates above 50%, and ADG were reduced after inclusion of SPN reached 25% of added N. Feed efficiency (the reciprocal of the efficiency of gain, which is represented by G:F) declined linearly (P < 0.001) with each incremental increase in SPN. Addition of up to 40% added N as SPN in goat diets caused no change in DMI, digestibility of DM or fiber, or N retention. Ruminal VFA concentrations showed little variation in either species. Increasing the proportion of SPN in the feed caused linear declines in ruminal NH(3) in steers (P < 0.001). Increasing SPN in goat diets, however, resulted in only a trend toward reductions of this parameter (P = 0.14). The decreases observed may have resulted from decreasing ruminal protein degradability or increasing fat caused by increasing the proportion of SPN in the feed. Urinary urea N as a percentage of urinary N showed significant declines in cattle, but not in goats, over the ranges of SPN offered. These results indicate that SPN can be included in diets for ruminants to supply up to 40% of supplemental N with little negative impact on animal performance.

Transforming the "unacceptable" donor: outcomes from the adoption of a standardized donor management technique.

PubMed

Wheeldon, D R; Potter, C D; Oduro, A; Wallwork, J; Large, S R

1995-01-01

Donor management remains one of the most neglected areas of transplantation. A comprehensive donor management regimen has been developed. The results of the application of this strategy form the basis of this report. Full hemodynamic data were collected from 150 multiorgan donors between October 1990 and August 1993. The data were collected at the time of donor team arrival, after insertion of a pulmonary artery floatation catheter and immediately before cardiac excision. Fifty-two donors (35%) fell well outside our minimum acceptance criteria on arrival. Twenty-one of fifty-two had a mean arterial pressure less than 55 mm Hg (mean 47 mm Hg) despite inotropic support in most cases; 10 of 52 had a central venous pressure greater than 15 mm Hg (mean 18.0 mm Hg); 2 of 52 had a high inotrope requirement greater than 20 micrograms/kg/min (mean 25 micrograms/kg/min). After the insertion of a pulmonary artery floatation catheter, an additional 13 of 52 donors were found to have a pulmonary capillary wedge pressure greater than 15 mm Hg (mean 19.8 mm Hg), and the final 6 of 52 had a low left ventricular stroke work index, less than 15 gm (mean 12.8 gm). After optimal management, including hormone replacement 44 of 52 donors yielded transplantable organs (29 hearts, 15 heart and lung blocks). Thirty-seven of forty-four patients (84%) were alive and well from 13 to 48 months after transplantation. There were five early deaths (11%) caused by infection (heart), adult respiratory distress syndrome (heart), arrhythmia (heart), cerebrovascular event (heart and lung), and infection (heart, lung, and liver). Two late deaths (5%) occurred as a result of tamponade (3 months, heart) and infection (14 months, heart and lung). Eight of fifty-two organs were still unsuitable for transplantation after optimum management during the splanchnic dissection as a result of inotrope dependency (n = 4), left ventricular hypertrophy (n = 2), and coronary artery disease (n = 2). The data indicate that, of the organs which initially fall outside our transplant acceptance criteria, 92% are capable of functional resuscitation. Conversely, superficial assessment may not show compromised function. Optimizing cardiovascular performance also has important implications for the viability of all transplantable organs. This aggressive approach to donor management has resulted in the transplantation of 44 donor hearts that may otherwise have been turned down or inappropriately managed.

Hollow silica microspheres for buoyancy-assisted separation of infectious pathogens from stool.

PubMed

Weigum, Shannon E; Xiang, Lichen; Osta, Erica; Li, Linying; López, Gabriel P

2016-09-30

Separation of cells and microorganisms from complex biological mixtures is a critical first step in many analytical applications ranging from clinical diagnostics to environmental monitoring for food and waterborne contaminants. Yet, existing techniques for cell separation are plagued by high reagent and/or instrumentation costs that limit their use in many remote or resource-poor settings, such as field clinics or developing countries. We developed an innovative approach to isolate infectious pathogens from biological fluids using buoyant hollow silica microspheres that function as "molecular buoys" for affinity-based target capture and separation by floatation. In this process, antibody functionalized glass microspheres are mixed with a complex biological sample, such as stool. When mixing is stopped, the target-bound, low-density microspheres float to the air/liquid surface, which simultaneously isolates and concentrates the target analytes from the sample matrix. The microspheres are highly tunable in terms of size, density, and surface functionality for targeting diverse analytes with separation times of ≤2min in viscous solutions. We have applied the molecular buoy technique for isolation of a protozoan parasite that causes diarrheal illness, Cryptosporidium, directly from stool with separation efficiencies over 90% and low non-specific binding. This low-cost method for phenotypic cell/pathogen separation from complex mixtures is expected to have widespread use in clinical diagnostics as well as basic research. Copyright © 2016 Elsevier B.V. All rights reserved.

Intestinal parasitosis in school children of Lalitpur district of Nepal

PubMed Central

2013-01-01

Background Enteric parasites are the most common cause of parasitic diseases and cause significant morbidity and mortality, particularly in developing countries like Nepal. The objective of this study was to estimate the prevalence and risk factors of intestinal parasitic infections among school going children of Lalitpur district of Nepal. Methods A total of 1392 stool samples were collected from school children of two government, two private and two community schools of the same district. The stool samples were examined for evidence of parasitic infections by direct microscopy and confirmed by concentration methods (formal ether sedimentation technique or floatation technique by using Sheather’s sugar solution). Modified Ziehl-Neelsen (ZN) staining was performed for the detection of coccidian parasites. Results Prevalence of intestinal parasitosis was found to be 16.7%. The highest prevalence rate was seen with Giardia lamblia (7.4%) followed by Entamoeba histolytica (3.4%) and Cyclospora cayetanensis (1.6%). Children aged 11–15 years and the ones belonging to family of agriculture workers were most commonly affected. Hand washing practice and type of drinking water also showed significant difference. Conclusions The burden of parasitic infections among the school children, coupled with the poor sanitary conditions in the schools, should be regarded as an issue of public health priority and demands for effective school health programs involving periodic health education and screening. PMID:24207086

Effect of three typical sulfide mineral flotation collectors on soil microbial activity.

PubMed

Guo, Zunwei; Yao, Jun; Wang, Fei; Yuan, Zhimin; Bararunyeretse, P; Zhao, Yue

2016-04-01

The sulfide mineral flotation collectors are wildly used in China, whereas their toxic effect on soil microbial activity remains largely unexplored. In this study, isothermal microcalorimetric technique and soil enzyme assay techniques were employed to investigate the toxic effect of typical sulfide mineral flotation collectors on soil microbial activity. Soil samples were treated with different concentrations (0-100 μg•g - 1 soil) of butyl xanthate, butyl dithiophosphate, and sodium diethyldithiocarbamate. Results showed a significant adverse effect of butyl xanthate (p < 0.05), butyl dithiophosphate, and sodium diethyldithiocarbamate (p < 0.01) on soil microbial activity. The growth rate constants k decreased along with the increase of flotation collectors concentration from 20.0 to 100.0 μg•g(-1). However, the adverse effects of these three floatation collectors showed significant difference. The IC 20 of the investigated flotation reagents followed such an order: IC 20 (butyl xanthate) > IC 20 (sodium diethyldithiocarbamate) > IC 20 (butyl dithiophosphate) with their respective inhibitory concentration as 47.03, 38.36, and 33.34 μg•g(-1). Besides, soil enzyme activities revealed that these three flotation collectors had an obvious effect on fluorescein diacetate hydrolysis (FDA) enzyme and catalase (CAT) enzyme. The proposed methods can provide meaningful toxicological information of flotation reagents to soil microbes in the view of metabolism and biochemistry, which are consistent and correlated to each other.

A cross-sectional study on schistosomiasis and soil-transmitted helminths in Mbita district, western Kenya using different copromicroscopic techniques.

PubMed

Ng'etich, Annette I; Rawago, Fredrick O; Jura, Walter G Z O; Mwinzi, Pauline N; Won, Kimberly Y; Odiere, Maurice R

2016-02-16

Identification of populations to be targeted for individual treatment and broad-spectrum therapy in schistosomiasis-endemic areas, assessment of therapy efficacy, morbidity, and evaluation of control strategies need to be based on reliable diagnostic tools. Kato-Katz is routinely used and remains the standard diagnostic technique for schistosomiasis, despite its many challenges. This study was conducted in Nyamanga village, Mbita, western Kenya, and evaluated the diagnostic performance of Kato-Katz, Mini-Parasep and modified Mini-FLOTAC techniques in detection of Schistosoma mansoni and soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura and hookworm) ova. Stool samples from 132 individuals were screened for eggs of S. mansoni by the 3 techniques. Mini-Parasep faecal parasite concentrator (Apacor Ltd, England), a single-use diagnostic device with a built-in filter for faecal concentration of helminth eggs by sedimentation was employed on stool samples fixed in 10% formalin. A modified Mini-FLOTAC (University of Naples, Italy) was based on floatation of helminths eggs with two different solutions (FS2 and FS7) using a closed system (Fill-FLOTAC) with 5% formalin. Kato-Katz was performed following WHO recommendation. Prevalence of S. mansoni and STH, sensitivity and degree of agreement among the 3 techniques were determined. Prevalence of S. mansoni was 47.0%, 34.1% and 20.5% by Mini-Parasep, Kato-Katz and modified Mini-FLOTAC FS7 techniques, respectively. Prevalence of any STH infection was 6.1%, 3.0%, 6.1% and 6.8% by Mini-Parasep, Kato-Katz, modified Mini-FLOTAC FS2 and modified Mini-FLOTAC FS7 techniques, respectively. Considering the pooled results of the three methods (Mini-Parasep, Kato-Katz and modified Mini-FLOTAC FS7) as diagnostic 'gold' standard, the sensitivity of Mini-Parasep, Kato-Katz and modified Mini-FLOTAC FS7 for S. mansoni was 77.5%, 56.1%, and 33.8%, respectively. Mini-Parasep and modified Mini-FLOTAC FS7 techniques had moderate (κ = 0.46) and fairly good (κ = 0.25) agreements with Kato-Katz for S. mansoni, respectively. Mini-Parasep detected a higher proportion of light intensity S. mansoni infections compared to Kato-Katz, which detected high proportions of heavy infections. Mini-Parasep detected a similar mean number of S. mansoni eggs per gram (EPG) of stool compared to the standard Kato-Katz (62.9 vs 97.3; t (131) = -0.49, P = 0.6265) and significantly higher EPG compared to the modified Mini-FLOTAC FS7 (62.9 vs 34.6; t (131) = 5.39, P < 0.0001). The high sensitivity of Mini-Parasep suggests its promising potential as an alternative tool in enhancing diagnosis and in monitoring schistosomiasis transmission and determining endpoint of intervention programs, especially in low endemicity areas. Mini-Parasep is also easy to operate, safe and also permits work with fresh stool.

Turbulence Measurements from a Moored Platform at Mid-Depth in a Swift Tidal Channel

NASA Astrophysics Data System (ADS)

Hay, Alex; Lueck, Rolf; Wolk, Fabian; McMillan, Justine

2014-05-01

Results are presented from a turbulence experiment with a 3-m long streamlined floatation body, instrumented with velocity shear probes, fast-response thermistors, a 1 MHz Acoustic Doppler Current Profiler (AD2CP), and an Acoustic Doppler Velocimeter (ADV). The system was deployed over seven tidal cycles at mid-depth in a 30-m deep tidal channel in the lower Bay of Fundy, Canada. Peak flow speeds exceeded 2 m s-1, and while 10-min time scale average speeds were similar between ebb and flood, the variances were markedly higher during flood. Turbulent kinetic energy (TKE) dissipation rates measured with the shear probes exhibit a pronounced flood/ebb contrast: O(10-4) W kg-1 peak values during flood, but lower by an order of magnitude during ebb. Dissipation rates follow u3 scaling over a wide range of flow speeds between 0.5 and 2.5 m s-1. Below 0.5 m s-1 an asymmetry in the mounting arrangement caused the floatation body to pitch upward, biasing the measured dissipation values high. The ADV on the platform registered mean speed - used to implement Taylor's hypothesis - which was corroborated with the platform-mounted ADCP. Additional ADCPs were also deployed on a nearby bottom pod, sampling at turbulence resolving rates - up to 8 Hz. Comparisons between the shear probe and acoustic estimates of the TKE spectrum and dissipation rate - at comparable depths - are presented.

Optimization of Cu-Zn Massive Sulphide Flotation by Selective Reagents

NASA Astrophysics Data System (ADS)

Soltani, F.; Koleini, S. M. J.; Abdollahy, M.

2014-10-01

Selective floatation of base metal sulphide minerals can be achieved by using selective reagents. Sequential floatation of chalcopyrite-sphalerite from Taknar (Iran) massive sulphide ore with 3.5 % Zn and 1.26 % Cu was studied. D-optimal design of response surface methodology was used. Four mixed collector types (Aer238 + SIPX, Aero3477 + SIPX, TC1000 + SIPX and X231 + SIPX), two depressant systems (CuCN-ZnSO4 and dextrin-ZnSO4), pH and ZnSO4 dosage were considered as operational factors in the first stage of flotation. Different conditions of pH, CuSO4 dosage and SIPX dosage were studied for sphalerite flotation from first stage tailings. Aero238 + SIPX induced better selectivity for chalcopyrite against pyrite and sphalerite. Dextrin-ZnSO4 was as effective as CuCN-ZnSO4 in sphalerite-pyrite depression. Under optimum conditions, Cu recovery, Zn recovery and pyrite content in Cu concentrate were 88.99, 33.49 and 1.34 % by using Aero238 + SIPX as mixed collector, CuCN-ZnSO4 as depressant system, at ZnSO4 dosage of 200 g/t and pH 10.54. When CuCN was used at the first stage, CuSO4 consumption increased and Zn recovery decreased during the second stage. Maximum Zn recovery was 72.19 % by using 343.66 g/t of CuSO4, 22.22 g/t of SIPX and pH 9.99 at the second stage.

[Study on preparation of phenols gastric floating tablet].

PubMed

Zhai, Xiao-Ling; Ni, Jian; Gu, Yu-Long

2008-01-01

To study the preparation of phenols gastric floating tablet. The tablets which were prepared using Eudragit IV, HPMC(K4M), MCC101 and Octadecanol as excipients were evaluated by vitro floatation and releasing performance. The pressure of preparationg was also study to select the optimal preparation. The tablets were successfully prepared in which the drug, Eudragit IV, Octadecanol were 31% respectively,and MCC101 was 7%. And 3-4 kg was found to be the eligible pressure. The study was found to be effective in the process of phenols gastric floating tablet.

Nitazoxanide in the treatment of Ascaris lumbricoides in a rural zone of Colima, Mexico.

PubMed

Galvan-Ramirez, M L; Rivera, N; Loeza, M E; Avila, X; Acero, J; Troyo, R; Bernal, R

2007-09-01

Intestinal parasites in Mexico are an endemic problem. A study was conducted in children, teenagers and adults in a rural community in Colima, Mexico to examine the prevalence and intensity of Ascaris lumbricoides infection and to evaluate the parasitological and clinical efficacy of nitazoxanide (NTZ). Two hundred and eighty children, teenagers and adults participated in this study. Parasitological diagnosis from faeces was confirmed by three consecutive stool samples using the floatation concentration Faust method. Egg counts were performed as described by the Kato-Katz technique before and after treatment. A questionnaire was systematically applied to obtain information about socio-economic status and hygienic habits. One hundred and six participants (38%) were diagnosed as harbouring intestinal parasites, and 86 of them (81%) were infected with A. lumbricoides. All patients with ascariasis infections underwent a complete physical examination before and after NTZ treatment. NTZ resolved 88% of the ascariasis cases, with a 89% clinical efficacy, and there was a 97.5% reduction in the levels of morbidity. The most intense infections for A. lumbricoides were found in housewives, and statistically significant associations were found between ascariasis and the absence of drainage and living in houses with dirt floors.

Formulation and evaluation of non-effervescent floating tablets of losartan potassium.

PubMed

Getyala, Anil; Gangadharappa, H V; Prasad, M Sarat Chandra; Reddy, M Praveen Kumar; Kumar, T M Pramod

2013-10-01

The aim of the work is to modify the solubility and bioavailability of Losartan potassium, by employing noneffervescent floating drug delivery (tablet dosage forms). Non-effervescent systems are a type of floating drug delivery systems, that have been used to boost the gastric residence and the floatation time in the gastro intestinal tract. The study included formulation of floating tablets using polymers like Chitosan and Karaya gum as matrix forming agents. Accurel(®) MP 1000 was used as floating agent. The tablets were prepared by direct compression technique. FTIR, DSC studies conformed that there was no incompatibility between the polymer and the drug. Tablet preformulation parameters were within the Pharmacopoeial limit. Tablet showed zero lag time, contisnuance of buoyancy for >12 h. The tablet showed good in vitro release. Drug release was through swelling and abided by the gellation mechanism. In vivo X-ray studies depicted that tablets continued to float in the GIT for 12 h. Accelerated stability showed that, tablets were stable for over 6 month. Thus the prepared non-effervescent floating tablet of Losartan potassium can be used for the treatment of hypertension for more than 12 h with single dose administration.

Development of a Sitting MicroEnvironment Simulator for wheelchair cushion assessment.

PubMed

Freeto, Tyler; Cypress, Allissa; Amalraj, Sarah; Yusufishaq, Mohamed Shaif; Bogie, Kath M

2016-08-01

Pressure ulcers (PU) are a common comorbidity among wheelchair users. An appropriate wheelchair cushion is essential to relieve pressure and reduce PU development during sitting. The microenvironment, specifically excessive heat and moisture, impacts risk for PU development. An effective wheelchair cushion should maintain a healthy microenvironment at the seating interface. Measurement of heat and moisture can characterize microenvironmental conditions at the wheelchair cushion interface under load. We describe the development of a Sitting MicroEnvironment Simulator (SMES) for the reliable assessment of wheelchair cushion microenvironments. The prototype SMES was developed for use mounted on a Materials Testing Systems (MTS) 810(®) uniaxial servo-hydraulic loading rig and used to assess microenvironmental conditions for Jay Medical Jay 2(®), Roho High Profile Dry Floatation(®) and Low Profile Dry Floatation(®) cushions and a novel modular gel cushion. Each cushion was assessed for two hours in triplicate. The SMES was used to load the cushions to 300N ± 10N, with an interface surface temperature of 37 °C±1 °C and fluid delivery of 13 mL/h±1 mL/h of water. Interface temperature and humidity were measured at the left ischial tuberosity (IT) region every five minutes. Heat and moisture responses were similar for the three commercial cushions. The modular gel cushion stayed cooler for at least 15 min longer than any commercial cushion. The SMES maintained performance to technical specifications for over one hundred hours of total testing and is a reliable tool for characterizing the microenvironmental conditions of wheelchair cushions. Published by Elsevier Ltd.

RoHo Dry Floatation system: an alternative means of pressure relief.

PubMed

Williams, C

Pressure sores are believed to occur as a result of two pressures, external pressure leading to occlusion, and disruptive shearing forces causing endothelial damage to the micro circulation. One of the main principles, therefore, of pressure sore prevention is relief or reduction of pressure. Scandinavian Mobility produces a range of systems--therapeutic cushions, specialist cushions and products, and mattresses--that can reduce the pressure, reportedly achieving interface pressures of 21-28 mmHg. These systems have been shown to be cost-effective in the clinical setting and provide pressure relief in low-, medium- and high risk patients.

Exosome and Microvesicle-Enriched Fractions Isolated from Mesenchymal Stem Cells by Gradient Separation Showed Different Molecular Signatures and Functions on Renal Tubular Epithelial Cells.

PubMed

Collino, Federica; Pomatto, Margherita; Bruno, Stefania; Lindoso, Rafael Soares; Tapparo, Marta; Sicheng, Wen; Quesenberry, Peter; Camussi, Giovanni

2017-04-01

Several studies have suggested that extracellular vesicles (EVs) released from mesenchymal stem cells (MSCs) may mediate MSC paracrine action on kidney regeneration. This activity has been, at least in part, ascribed to the transfer of proteins/transcription factors and different RNA species. Information on the RNA/protein content of different MSC EV subpopulations and the correlation with their biological activity is currently incomplete. The aim of this study was to evaluate the molecular composition and the functional properties on renal target cells of MSC EV sub-populations separated by gradient floatation. The results demonstrated heterogeneity in quantity and composition of MSC EVs. Two peaks of diameter were observed (90-110 and 170-190 nm). The distribution of exosomal markers and miRNAs evaluated in the twelve gradient fractions showed an enrichment in fractions with a flotation density of 1.08-1.14 g/mL. Based on this observation, we evaluated the biological activity on renal cell proliferation and apoptosis resistance of low (CF1), medium (CF2) and high (CF3) floatation density fractions. EVs derived from all fractions, were internalized by renal cells, CF1 and CF2 but not CF3 fraction stimulated significant cell proliferation. CF2 also inhibited apoptosis on renal tubular cells submitted to ischemia-reperfusion injury. Comparative miRNomic and proteomic profiles reveal a cluster of miRNAs and proteins common to all three fractions and an enrichment of selected molecules related to renal regeneration in CF2 fraction. In conclusion, the CF2 fraction enriched in exosomal markers was the most active on renal tubular cell proliferation and protection from apoptosis.

Thermal effects of dorsal head immersion in cold water on nonshivering humans.

PubMed

Giesbrecht, Gordon G; Lockhart, Tamara L; Bristow, Gerald K; Steinman, Allan M

2005-11-01

Personal floatation devices maintain either a semirecumbent flotation posture with the head and upper chest out of the water or a horizontal flotation posture with the dorsal head and whole body immersed. The contribution of dorsal head and upper chest immersion to core cooling in cold water was isolated when the confounding effect of shivering heat production was inhibited with meperidine (Demerol, 2.5 mg/kg). Six male volunteers were immersed four times for up to 60 min, or until esophageal temperature = 34 degrees C. An insulated hoodless dry suit or two different personal floatation devices were used to create four conditions: 1) body insulated, head out; 2) body insulated, dorsal head immersed; 3) body exposed, head (and upper chest) out; and 4) body exposed, dorsal head (and upper chest) immersed. When the body was insulated, dorsal head immersion did not affect core cooling rate (1.1 degrees C/h) compared with head-out conditions (0.7 degrees C/h). When the body was exposed, however, the rate of core cooling increased by 40% from 3.6 degrees C/h with the head out to 5.0 degrees C/h with the dorsal head and upper chest immersed (P < 0.01). Heat loss from the dorsal head and upper chest was approximately proportional to the extra surface area that was immersed (approximately 10%). The exaggerated core cooling during dorsal head immersion (40% increase) may result from the extra heat loss affecting a smaller thermal core due to intense thermal stimulation of the body and head and resultant peripheral vasoconstriction. Dorsal head and upper chest immersion in cold water increases the rate of core cooling and decreases potential survival time.

Prevalence and molecular characterization of Cryptosporidium species in cattle and buffalo calves in Mumbai region of India.

PubMed

Hingole, A C; Gudewar, J G; Pednekar, R P; Gatne, M L

2017-03-01

Faecal samples of cattle and buffaloes of Mumbai region collected between November 2012 to June 2013 were analysed by conventional and molecular tools to note the prevalence of cryptosporidiosis and species involved in the infection. Conventional analysis viz., direct faecal smear examination, faecal smear examination after normal saline sedimentation, Sheather's floatation and Sheather's floatation sedimentation smear methods demonstrated oocysts of Cryptosporidium in 141 (36.06 %) of 391 samples with higher occurrence in buffaloes (36.99 %) than cattle (34.48 %). Diarrhoeic loose faeces showed higher prevalence (42.07 %) than apparently normal faeces (31.72 %) irrespective of the host species. When data were arranged as per age groups viz., calves of 0-1 month, 1-2 months, 2-3 months and adults, the highest prevalence was noted in the youngest group (47.12 %) declining gradually with the advancing age with lowest (6.25 %) in adults indicating inverse correlation between prevalence rate and age of the host. These differences were statistically significant in case of buffaloes. Cryptosporidium andersoni was tentatively identified by morphometric analysis. By employing molecular tools like nested PCR, PCR-RFLP and sequence analysis of few samples showed good correlation in the identification of species of Cryptosporidium involved in the infection and demonstrated occurrence of C. parvum , C. ryanae and C. bovis. Thus all the four commonly occurring bovine species of Cryptosporidium were encountered in the study area which appears to be a first record reporting the occurrence of Cryptosporidium with species level identification in large ruminants from Western region of India. Additionally, the public health significance of C. parvum was also discussed in light of epidemiological factors pertaining to the region.

Making Mercury's Core with Light Elements

NASA Technical Reports Server (NTRS)

Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Ross, D. Kent

2016-01-01

Recent results obtained from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft showed the surface of Mercury has low FeO abundances (less than 2 wt%) and high S abundances (approximately 4 wt%), suggesting the oxygen fugacity of Mercury's surface materials is somewhere between 3 to 7 log10 units below the IW buffer. The highly reducing nature of Mercury has resulted in a relatively thin mantle and a large core that has the potential to exhibit an exotic composition in comparison to the other terrestrial planets. This exotic composition may extend to include light elements (e.g., Si, C, S). Furthermore, has argued for a possible primary floatation crust on Mercury composed of graphite, which may require a core that is C-saturated. In order to investigate mercurian core compositions, we conducted piston cylinder experiments at 1 GPa, from 1300 C to 1700 C, using a range of starting compositions consisting of various Si-Fe metal mixtures (Si5Fe95, Si10Fe90, Si22Fe78, and Si35Fe65). All metals were loaded into graphite capsules used to ensure C-saturation during the duration of each experimental run. Our experiments show that Fe-Si metallic alloys exclude carbon relative to more Fe-rich metal. This exclusion of carbon commences within the range of 5 to 10 wt% Si. These results indicate that if Mercury has a Si-rich core (having more than approximately 5 wt% silicon), it would have saturated in carbon at low C abundances allowing for the possible formation of a graphite floatation crust as suggested by. These results have important implications for the thermal and magmatic evolution of Mercury.

QbD-Enabled Development of Novel Stimuli-Responsive Gastroretentive Systems of Acyclovir for Improved Patient Compliance and Biopharmaceutical Performance.

PubMed

Singh, Bhupinder; Kaur, Anterpreet; Dhiman, Shashi; Garg, Babita; Khurana, Rajneet Kaur; Beg, Sarwar

2016-04-01

The current studies entail systematic quality by design (QbD)-based development of stimuli-responsive gastroretentive drug delivery systems (GRDDS) of acyclovir using polysaccharide blends for attaining controlled drug release profile and improved patient compliance. The patient-centric quality target product profile was defined and critical quality attributes (CQAs) earmarked. Risk assessment studies, carried out through Ishikawa fish bone diagram and failure mode, effect, and criticality analysis, helped in identifying the plausible risks or failure modes affecting the quality attributes of the drug product. A face-centered cubic design was employed for systematic development and optimization of the concentration of sodium alginate (X 1) and gellan (X 2) as the critical material attributes (CMAs) in the stimuli-responsive formulations, which were evaluated for CQAs viz. viscosity, gel strength, onset of floatation, and drug release characteristics. Mathematical modeling was carried out for generation of design space, and optimum formulation was embarked upon, exhibiting formulation characteristics marked by excellent floatation and bioadhesion characteristics along with promising drug release control up to 24 h. Drug-excipient compatibility studies through FTIR and DSC revealed absence of any interaction(s) among the formulation excipients. In vivo pharmacokinetic studies in Wistar rats corroborated extension in the drug absorption profile from the optimized stimuli-responsive GR formulations vis-à-vis the marketed suspension (ZOVIRAX®). Establishment of in vitro/in vivo correlation (IVIVC) revealed a high degree of correlation between the in vitro and in vivo data. In a nutshell, the present investigations report the successful development of stimuli-responsive GRDDS of acyclovir, which can be applicable as a platform approach for other drugs too.

Influence of refrigeration and formalin on the floatability of Giardia duodenalis cysts.

PubMed

Moitinho, M d; Bertoli, M; Guedes, T A; Ferreira, C S

1999-01-01

Giardia duodenalis cysts obtained from fresh fecal samples, fecal samples kept under refrigeration and fecal samples treated with formalin were studied as to their floatability on sucrose solutions with the following specific gravities: 1,040 kg/m3; 1,050 kg/m3; 1, 060 kg/m3; 1,070 kg/m3; 1,080 kg/m3; 1,090 kg/m3; 1,100 kgm3; 1,150 kg/m3; 1,200 kg/m3; and 1,250 kg/m3, contained within counting-chambers 0.17 mm high. Cysts that floated on and those settled down as sediments were counted, and had their percentages estimated. Sucrose solutions of 1,200 kg/m3 specific gravity (the average specific gravity of diluting liquids employed in floatation techniques) caused to float 77.7%, 78.4% and 6.6% of the G. duodenalis cysts obtained, respectively, from fresh fecal samples, fecal samples kept under refrigeration, and fecal samples treated with formalin. Cysts obtained both from fresh fecal samples and fecal samples kept under refrigeration presented similar results concerning floatability. It was observed, however, that the treatment of feces with formalin diminished the cysts floatability under the various specific gravities studied. This results should influence, the recommendations for transport and storage of fecal samples used for parasitological coproscopy.

Method and apparatus for production of subsea hydrocarbon formations

DOEpatents

Blandford, Joseph W.

1995-01-01

A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external floatation tanks located below the water surface. The surface buoy is secured to the seabed by one or more tendons which are anchored to a foundation with piles imbedded in the seabed. The system accommodates multiple versions on the surface buoy configuration.

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

Rehder, J.B.

The project focuses on an appropriate technology for small-scale hydro power: floating waterwheels and turbines. For background, relic and existing systems such as early floating mills, traditional Amish waterwheels, and micro-hydro systems are examined. In the design phase of the project, new designs for Floating Hydro Power Systems include: an analysis of floatation materials and systems; a floating undershot waterwheel design; a floating cylinder (fiberglass storage tank) design; a submerged tube design; and a design for a floating platform with submerged propellers. Finally, in the applications phase, stream flow data from East Tennessee streams are used in a discussion ofmore » the potential applications of floating hydro power systems in small streams.« less

Levitation in physics.

PubMed

Brandt, E H

1989-01-20

Several physical effects allow free floatation of solid and even liquid matter. Materials may be levitated by a jet of gas, by intense sound waves, or by beams of laser light. In addition, conductors levitate in strong radio-frequency fields, charged particles in alternating electric fields, and magnets above superconductors or vice versa. Although levitation by means of ferromagnets is unstable, supper-conductors may be suspended both above and below a magnet as a result of flux pinning. Levitation is used for containerless processing and investigation of materials, for frictionless bearings and high-speed ground transportation, for spectroscopy of single atoms and microparticles, and for demonstrating superconductivity in the new oxide superconductors.

Snare-assisted anterograde balloon mitral and aortic valvotomy using Inoue balloon catheter.

PubMed

Krishnan, Mangalath N; Syamkumar, M D; Sajeev, C G; Venugopal, K; Johnson, Francis; Vinaykumar, D; Velayudhan, C C; Jayakumar, T G

2007-01-02

We performed concurrent antegrade mitral and aortic valvotomy using Inoue dilatation catheter in 3 cases of combined rheumatic mitral and aortic stenosis. Following mitral valvotomy by standard procedure, aortic valve was crossed with the help of a floatation catheter. Stiff long length guide wire was fixed in descending aorta using a snare. Inoue catheter was threaded over the wire across the aortic valve and aortic valvotomy completed. Mitral valve area increased from mean 1 cm2 to 2 cm2; aortic gradient dropped from mean of 97 mm to 36 mm. Concurrent anterograde balloon mitral and aortic valvotomy may be effective and safe.

Westinghouse modular grinding process - improvement for follow on processes

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

Fehrmann, Henning

2013-07-01

In nuclear power plants (NPP) ion exchange (IX) resins are used in several systems for water treatment. The resins can be in bead or powdered form. For waste treatment of spent IX resins, two methods are basically used: Direct immobilization (e.g. with cement, bitumen, polymer or High Integrity Container (HIC)); Thermal treatment (e.g. drying, oxidation or pyrolysis). Bead resins have some properties (e.g. particle size and density) that can have negative impacts on following waste treatment processes. Negative impacts could be: Floatation of bead resins in cementation process; Sedimentation in pipeline during transportation; Poor compaction properties for Hot Resin Supercompactionmore » (HRSC). Reducing the particle size of the bead resins can have beneficial effects enhancing further treatment processes and overcoming prior mentioned effects. Westinghouse Electric Company has developed a modular grinding process to crush/grind the bead resins. This modular process is designed for flexible use and enables a selective adjustment of particle size to tailor the grinding system to the customer needs. The system can be equipped with a crusher integrated in the process tank and if necessary a colloid mill. The crusher reduces the bead resins particle size and converts the bead resins to a pump able suspension with lower sedimentation properties. With the colloid mill the resins can be ground to a powder. Compared to existing grinding systems this equipment is designed to minimize radiation exposure of the worker during operation and maintenance. Using the crushed and/or ground bead resins has several beneficial effects like facilitating cementation process and recipe development, enhancing oxidation of resins, improving the Hot Resin Supercompaction volume reduction performance. (authors)« less

Mini-FLOTAC and Kato-Katz: helminth eggs watching on the shore of Lake Victoria.

PubMed

Barda, Beatrice; Zepherine, Henry; Rinaldi, Laura; Cringoli, Giuseppe; Burioni, Roberto; Clementi, Massimo; Albonico, Marco

2013-07-31

One of the challenges for monitoring helminth control programmes based on preventive chemotherapy is the lack of a copro-parasitological gold-standard method that combines good sensitivity with quantitative performance, low cost, and easy-to-learn technique.The aim of our study was to evaluate and compare, the WHO recommended quantitative diagnostic technique (Kato-Katz) and the Mini-FLOTAC. Mini-FLOTAC is an innovative method based on floatation of helminths eggs with two different solutions (FS2 and FS7) using a close system (Fill-FLOTAC) with 5% fixative. Kato-Katz was performed following WHO recommendation. The study was carried out in a rural part of Tanzania, close to Lake Victoria, where the laboratory facilities are fairly scarce, and the basic technique used in the local laboratory (direct smear) was taken as reference standard. 201 children were screened for intestinal helminths and 91% of them were found to be positive. The agreement among the three techniques was calculated with k Cohen coefficient and was fairly good (k = 0.4), although the Mini-FLOTAC results were more sensitive for hookworm (98%) with FS2, and for S.mansoni (90%) with FS7 followed by Kato-Katz (91% and 60% respectively) and direct smear (30% and 10% respectively). A good agreement was found between Mini-FLOTAC and Kato-Katz (k = 0.81) with FS7 (k = 0.76) for hookworm diagnosis and a fairly good one for S.mansoni diagnosis (k = 0.5). For both infections we had a poor agreement between the two quantitative techniques and the direct smear (k<0.3). Kato-Katz diagnosed a higher number of eggs (calculated by arithmetic mean) both for hookworm (455 vs 424 EPG) and for S.mansoni (71 vs 58 EPG) compared with the Mini-FLOTAC, but the differences were not significant (p = 0.4). Mini-FLOTAC is a promising technique, comparable and as sensitive as the Kato-Katz, which is the recommended method in intestinal helminthology for monitoring helminth control programmes. A comparative advantage of the Mini-FLOTAC is that it comprises of a closed system with preserved samples that both protects the operators and allows subsequent examination of the samples. Further studies are needed to validate the mini-FLOTAC with other quantitative techniques (McMaster) and in different settings where other soil-transmitted helminths are also endemic.

Bioavailability enhancement of baclofen by gastroretentive floating formulation: statistical optimization, in vitro and in vivo pharmacokinetic studies.

PubMed

Thakar, Krishna; Joshi, Garima; Sawant, Krutika K

2013-06-01

The study was aimed to improve bioavailability of baclofen by developing gastroretentive floating drug delivery system (GFDDS). Preliminary optimization was done to select various release retardants to obtain minimum floating lag time, maximum floating duration and sustained release. Optimization by 3(2) factorial design was done using Polyox WSR 303 (X1) and HPMC K4M (X2) as independent variables and cumulative percentage drug released at 6 h (Q6h) as dependent variable. Optimized formulation showed floating lag time of 4-5 s, floated for more than 12 h and released the drug in sustained manner. In vitro release followed zero ordered kinetics and when fitted to Korsemeyer Peppas model, indicated drug release by combination of diffusion as well as chain relaxation. In vivo floatability study confirmed floatation for more than 6 h. In vivo pharmacokinetic studies in rabbits showed Cmax of 189.96 ± 13.04 ng/mL and Tmax of 4 ± 0.35 h for GFDDS. The difference for AUC(0-T) and AUC(0-∞) between the test and reference formulation was statistically significant (p > 0.05). AUC(0-T) and AUC(0-∞) for GFDDS was 2.34 and 2.43 times greater than the marketed formulation respectively. GFDDS provided prolonged gastric residence and showed significant increase in bioavailability of baclofen.

Evaluation of the effectiveness of two support surfaces following myocutaneous flap surgery.

PubMed

Economides, N G; Skoutakis, V A; Carter, C A; Smith, V H

1995-01-01

Recurrence of pressure ulcers is a serious problem following myocutaneous flap surgery and can lead to prolonged and expensive hospitalization. One of the most important aspects of patient care after surgery is the monitoring of reduced pressure in the area of the flap. Usually reducing pressure requires an expensive high-tech support surface. The purpose of this study was to evaluate the effectiveness of a less expensive support surface. There were 12 patients involved in a clinical trial that lasted 14 days and compared the effectiveness of the ROHO dry-floatation mattress to that of the Clinitron bed. Findings indicated that post-operative patients were effectively treated on either support surface.

[Target chemotherapy of intestinal nematode infection in area with low endemicity].

PubMed

Zhang, Tao; Shen, Yi-ping; Liu, Ying; Yang, Wei-ping; Shao, Jing-ou; Ju, Shao-you; Dong, Kai; Xu, Ju-ling; Jiang, Ji-min

2002-01-01

To evaluate the control measures for intestinal nematodiasis in endemic area with low prevalence and intensity of infection. Target chemotherapy was carried out in high-risk population based on the epidemiological characteristics such as age and clinical findings. Albendazole and mebendazole were administered each 200 mg once daily every year for 3 or 5 years. Saturated brine floatation and Kato-Katz thick smear techniques were used for stool examination to evaluate the efficacy of treatment. Two hundred residents from each of the three investigation villages were selected for target chemotherapy once a year for three years. The prevalence of intestinal nematodes decreased from 6.2% in 1995 to 5.4% in 1996 and 3.2% in 1997, and remained at 2.3% after three years in 2000. One control village where only primary school students were treated once a year for 5 years, the prevalence of Ascaris and Trichuris infection also decreased from 1.4% and 4.2% in 1995 to 0.9% and 1.4% in 2000, respectively. The target chemotherapy on the predisposed population to hookworm infection showed that the prevalence in the population above 41 years old was declined from 19.4% to 10.9%. The target chemotherapy is an economical and effective approach for the control of intestinal nematode infection in endemic area with low prevalence and intensity of infection.

CHANGES IN LIPID-ENCAPSULATED MICROBUBBLE POPULATION DURING CONTINUOUS INFUSION AND METHODS TO MAINTAIN CONSISTENCY

PubMed Central

KAYA, MEHMET; GREGORY, THOMAS S.; DAYTON, PAUL A.

2009-01-01

Stabilized microbubbles are utilized as ultrasound contrast agents. These micron-sized gas capsules are injected into the bloodstream to provide contrast enhancement during ultrasound imaging. Some contrast imaging strategies, such as destruction-reperfusion, require a continuous injection of microbubbles over several minutes. Most quantitative imaging strategies rely on the ability to administer a consistent dose of contrast agent. Because of the buoyancy of these gas-filled agents, their spatial distribution within a syringe changes over time. The population of microbubbles that is pumped from a horizontal syringe outlet differs from initial population as the microbubbles float to the syringe top. In this manuscript, we study the changes in the population of a contrast agent that is pumped from a syringe due to microbubble floatation. Results are presented in terms of change in concentration and change in mean diameter, as a function of time, suspension medium, and syringe diameter. Data illustrate that the distribution of contrast agents injected from a syringe changes in both concentration and mean diameter over several minutes without mixing. We discuss the application of a mixing system and viscosity agents to keep the contrast solution more evenly distributed in a syringe. These results are significant for researchers utilizing microbubble contrast agents in continuous-infusion applications where it is important to maintain consistent contrast agent delivery rate, or in situations where the injection syringe cannot be mixed immediately prior to administration. PMID:19632760

Influence of hydroxypropyl methylcellulose on drug release pattern of a gastroretentive floating drug delivery system using a 3(2) full factorial design.

PubMed

Swain, Kalpana; Pattnaik, Satyanarayan; Mallick, Subrata; Chowdary, Korla Appana

2009-01-01

In the present investigation, controlled release gastroretentive floating drug delivery system of theophylline was developed employing response surface methodology. A 3(2) randomized full factorial design was developed to study the effect of formulation variables like various viscosity grades and contents of hydroxypropyl methylcellulose (HPMC) and their interactions on response variables. The floating lag time for all nine experimental trial batches were less than 2 min and floatation time of more than 12 h. Theophylline release from the polymeric matrix system followed non-Fickian anomalous transport. Multiple regression analysis revealed that both viscosity and content of HPMC had statistically significant influence on all dependent variables but the effect of these variables found to be nonlinear above certain threshold values.

Long-Term Observations of Atmospheric CO2, O3 and BrO over the Transitioning Arctic Ocean Pack-ice: The O-Buoy Chemical Network

NASA Astrophysics Data System (ADS)

Matrai, P.

2016-02-01

Autonomous, sea ice-tethered O-Buoys have been deployed (2009-2016) across the Arctic sea ice for long-term atmospheric measurements (http://www.o-buoy.org). O-Buoys (15) provide in-situ concentrations of three sentinel atmospheric chemicals, ozone, CO2 and BrO, as well as meteorological parameters and imagery, over the frozen ocean. O-Buoys were designed to transmit daily data over a period of 2 years while deployed in sea ice, as part of automated ice-drifting stations that include snow/ice measurement systems (e.g. Ice Mass Balance buoys) and oceanographic measurements (e.g. Ice Tethered Profilers). Seasonal changes in Arctic atmospheric chemistry are influenced by changes in the characteristics and presence of the sea ice vs. open water as well as air mass trajectories, especially during the winter-spring and summer-fall transitions when sea ice is melting and freezing, respectively. The O-Buoy Chemical Network provides the unique opportunity to observe these transition periods in real-time with high temporal resolution, and to compare them with those collected on land-based monitoring stations located. Due to the logistical challenges of measurements over the Arctic Ocean region, most long term, in-situ observations of atmospheric chemistry have been made at coastal or island sites around the periphery of the Arctic Ocean, leaving large spatial and temporal gaps that O-Buoys overcome. Advances in floatation, communications, power management, and sensor hardware have been made to overcome the challenges of diminished Arctic sea ice. O-Buoy data provide insights into enhanced seasonal, interannual and spatial variability in atmospheric composition, atmospheric boundary layer control on the amount of halogen activation, enhancement of the atmospheric CO2 signal over the more variable and porous pack ice, and to develop an integrated picture of the coupled ocean/ice/atmosphere system. As part of the Arctic Observing Network, we provide data to the community (www.aoncadis.org).

Characterisation of FOGs in grease trap waste from the processing of chickens in Thailand.

PubMed

Nitayapat, Nuttakan; Chitprasert, Pakamon

2014-06-01

Industrial firms that kill and process chickens generate wastewater that contains fat, oil, and grease (FOG). The FOGs are located in the fatty waste that is collected by floatation in grease traps. Chemical and physical characterisation of FOGs would provide useful information that would help in the development of methods designed to decrease the extent of pollution caused by disposal of the waste and to utilise commercially some of its lipid constituents. Employing these methods would enhance the profitability and competitive potential of these commercial organisations. Samples of grease trap waste from 14 firms in central Thailand have been examined. Due to the very different schemes of waste management employed by these firms, the physical appearance of their fatty wastes showed considerable variation. The chemical and physical properties of the FOGs present in these wastes showed considerable variation also. Large amounts of free fatty acids (10-70% as oleic acid) were detected in most of the 14 wastes and palmitic, cis-9-oleic, cis,cis-9,12-linoleic, stearic, and palmitoleic acids were the predominant species of free and esterified acids. Most of the FOGs were solid at temperatures below 40 °C. Many of them contained traces of heavy metals (Cu and Pb) and some contained traces of the pesticides dimethoate and cypermethrin. The content of these potentially hazardous substances would have to be considered very carefully before discarding the fatty wastes and during the development of methods designed to isolate their potentially profitable lipid constituents. Copyright © 2013 Elsevier Ltd. All rights reserved.

Beware Swan-Ganz complications. Perioperative management.

PubMed

Asteri, T; Tsagaropoulou, I; Vasiliadis, K; Fessatidis, I; Papavasi-Liou, E; Spyrou, P

2002-08-01

Since the introduction of the pulmonary artery catheter (PAC) in 1970 by Swan et al., various complications are recognized with the insertion and the use of Swan-Ganz catheter. We present two different cases with rare but life threatening complications which had been successfully managed. The first case is a carotid cannulation with an 8.5 Fr introducer sheath, in an attempt to insert a pulmonary catheter via the right internal jugular vein. Two weeks later, the patient was re-admitted to the hospital and when an arteriovenous fistulae (carotid artery-internal jugular vein) was diagnosed, he was treated surgically. The second case presents the rupture of the right atrium in the conjunction with the superior vena cava. This serious cardiac complication was developed during the floatation of the PAC and the lesion was repaired while the mitral valve replacement was in progress.

Ecology of the gastrointestinal parasites of Colobus vellerosus at Boabeng-Fiema, Ghana: possible anthropozoonotic transmission.

PubMed

Teichroeb, Julie A; Kutz, Susan J; Parkar, Unaiza; Thompson, R C Andrew; Sicotte, Pascale

2009-11-01

Parasite richness and prevalence in wild animals can be used as indicators of population and ecosystem health. In this study, the gastrointestinal parasites of ursine colobus monkeys (Colobus vellerosus) at the Boabeng-Fiema Monkey Sanctuary (BFMS), Ghana, were investigated. BFMS is a sacred grove where monkeys and humans have long lived in relatively peaceful proximity. Fecal samples (n = 109) were collected opportunistically from >27 adult and subadult males in six bisexual groups and one all-male band from July 2004 to August 2005. Using fecal floatation, we detected three protozoans (two Entamoeba sp., Isospora sp.), five nematodes (Ascaris sp., Enterobius sp., Trichuris sp., two strongyle sp.), and one digenean trematode. Using fluorescein labeled antibodies, we detected an additional protozoan (Giardia sp.), and with PCR techniques, we characterized this as G. duodenalis Assemblage B and also identified a protistan (Blastocystis sp., subtype 2). The most prevalent parasite species were G. duodenalis and Trichuris sp. Parasites were more prevalent in the long wet season than the long dry. Parasite prevalence did not vary by age, and average parasite richness did not differ by rank for males whose status remained unchanged. However, males that changed rank tended to show higher average parasite richness when they were lower ranked. Individuals that spent more time near human settlements had a higher prevalence of Isospora sp. that morphologically resembled the human species I. belli. The presence of this parasite and G. duodenalis Assemblage B indicates possible anthropozoonotic and/or zoonotic transmission between humans and colobus monkeys at this site.

Effect of renal replacement therapy on viscosity in end-stage renal disease patients.

PubMed

Feriani, M; Kimmel, P L; Kurantsin-Mills, J; Bosch, J P

1992-02-01

Viscosity, an important determinant of microcirculatory hemodynamics, is related to hematocrit (HCT), and may be altered by renal failure or its treatment. To assess these factors, we studied the effect of dialysis on the viscosity of whole blood, plasma, and reconstituted 70% HCT blood of eight continuous ambulatory peritoneal dialysis (CAPD) and nine hemodialysis (HD) patients under steady shear flow conditions at different shear rates, before and after dialysis, compared with nine normal subjects. The density of the red blood cells (RBCs), a marker of cell hydration, was measured in HD patients by a nonaqueous differential floatation technique. Whole blood viscosity was higher in controls than patients, and correlated with HCT before treatment (P less than 0.05) at shear rates of 11.5 to 230 s-1) in HD patients, and 23 to 230 s-1 in all end-stage renal disease (ESRD) patients. In contrast, whole blood viscosity correlated with HCT in CAPD patients only at the lowest shear rates (2.3 and 5.75 s-1, P less than 0.05). Plasma viscosity was higher in CAPD patients than both HD patients before treatment and controls (P less than 0.05, analysis of variance [ANOVA]), despite lower plasma total protein, albumin, and similar fibrinogen concentration compared with HD patients. When all samples were reconstituted to 70% HCT, CAPD patients had higher whole blood viscosity than control subjects'. The high HCT blood viscosity of the ESRD patients was higher than control subjects' at capillary shear rates, suggesting increased RBC aggregation and decreased RBC deformability in patients with renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Visibility enhancement of color images using Type-II fuzzy membership function

NASA Astrophysics Data System (ADS)

Singh, Harmandeep; Khehra, Baljit Singh

2018-04-01

Images taken in poor environmental conditions decrease the visibility and hidden information of digital images. Therefore, image enhancement techniques are necessary for improving the significant details of these images. An extensive review has shown that histogram-based enhancement techniques greatly suffer from over/under enhancement issues. Fuzzy-based enhancement techniques suffer from over/under saturated pixels problems. In this paper, a novel Type-II fuzzy-based image enhancement technique has been proposed for improving the visibility of images. The Type-II fuzzy logic can automatically extract the local atmospheric light and roughly eliminate the atmospheric veil in local detail enhancement. The proposed technique has been evaluated on 10 well-known weather degraded color images and is also compared with four well-known existing image enhancement techniques. The experimental results reveal that the proposed technique outperforms others regarding visible edge ratio, color gradients and number of saturated pixels.

Representing grounding line migration in synchronous coupling between a marine ice sheet model and a z-coordinate ocean model

NASA Astrophysics Data System (ADS)

Goldberg, D. N.; Snow, K.; Holland, P.; Jordan, J. R.; Campin, J.-M.; Heimbach, P.; Arthern, R.; Jenkins, A.

2018-05-01

Synchronous coupling is developed between an ice sheet model and a z-coordinate ocean model (the MITgcm). A previously-developed scheme to allow continuous vertical movement of the ice-ocean interface of a floating ice shelf ("vertical coupling") is built upon to allow continuous movement of the grounding line, or point of floatation of the ice sheet ("horizontal coupling"). Horizontal coupling is implemented through the maintenance of a thin layer of ocean ( ∼ 1 m) under grounded ice, which is inflated into the real ocean as the ice ungrounds. This is accomplished through a modification of the ocean model's nonlinear free surface evolution in a manner akin to a hydrological model in the presence of steep bathymetry. The coupled model is applied to a number of idealized geometries and shown to successfully represent ocean-forced marine ice sheet retreat while maintaining a continuous ocean circulation.

Experimental and modeling study of a two-stage pilot scale high solid anaerobic digester system.

PubMed

Yu, Liang; Zhao, Quanbao; Ma, Jingwei; Frear, Craig; Chen, Shulin

2012-11-01

This study established a comprehensive model to configure a new two-stage high solid anaerobic digester (HSAD) system designed for highly degradable organic fraction of municipal solid wastes (OFMSW). The HSAD reactor as the first stage was naturally separated into two zones due to biogas floatation and low specific gravity of solid waste. The solid waste was retained in the upper zone while only the liquid leachate resided in the lower zone of the HSAD reactor. Continuous stirred-tank reactor (CSTR) and advective-diffusive reactor (ADR) models were constructed in series to describe the whole system. Anaerobic digestion model No. 1 (ADM1) was used as reaction kinetics and incorporated into each reactor module. Compared with the experimental data, the simulation results indicated that the model was able to well predict the pH, volatile fatty acid (VFA) and biogas production. Copyright © 2012 Elsevier Ltd. All rights reserved.

Electrophoresis tests on STS-3 and ground control experiments - A basis for future biological sample selections

NASA Technical Reports Server (NTRS)

Morrison, D. R.; Lewis, M. L.

1982-01-01

Static zone electrophoresis is an electrokinetic method of separating macromolecules and small particles. However, its application for the isolation of biological cells and concentrated protein solutions is limited by sedimentation and convection. Microgravity eliminates or reduces sedimentation, floatation, and density-driven convection arising from either Joule heating or concentration differences. The advantages of such an environment were first demonstrated in space during the Apollo 14 and 16 missions. In 1975 the Electrophoresis Technology Experiment (MA-011) was conducted during the Apollo-Soyuz Test Project flight. In 1979 a project was initiated to repeat the separations of human kidney cells. One of the major objectives of the Electrophoresis Equipment Verification Tests (EEVT) on STS-3 was to repeat and thereby validate the first successful electrophoretic separation of human kidney cells. Attention is given to the EEVT apparatus, the preflight electrophoresis, and inflight operational results.

Excavating and loading equipment for peat mining

NASA Astrophysics Data System (ADS)

Mikhailov, A. V.; Zhigulskaya, A. I.; Yakonovskaya, T. B.

2017-10-01

Recently, the issues of sustainable development of Russian regions, related to ensuring energy security, are more urgent than ever. To achieve sustainable development, an integrated approach to the use of local natural resources is needed. Practically in all north regions of the Russian Federation, peat as a local natural resource is widespread, which has a practical application in the area of housing services. The paper presents the evaluation of technologies for open-pit peat mining, as well as analysis of technological equipment for peat production. Special attention is paid to a question of peat materials excavating and loading. The problem of equipment selection in a peat surface mine is complex. Many features, restrictions and criteria need to be considered. Use of low and ultra-low ground pressure excavators and low ground pressure front-end loaders with full-range tires to provide the necessary floatation in the peat bog environment is offered.

[Peculiarities of treatment policy for lower-limb phlebothromboses].

PubMed

Kletskin, A É; Kudykin, M N; Mukhin, A S; Durandin, P Iu

2014-01-01

Quality of treatment for acute venous thrombosis is determined by adequacy of conservative treatment and optimization of the operative procedure. We analysed the outcomes of management of 1,768 patients presenting with various forms of lower-limb phlebothrombosis. Deep veins were affected in 1,158 (65.5%) cases. Of these, thrombosis of crural veins was revealed in 672 (58%) patients, iliofemoral phlebothrombosis in 486 (42%) subjects. A total of 47 (9.7%) patients were operated on for iliofemoral thrombosis with floating thrombus confirmed by ultrasonic angioscanning. Criteria for floatation were determined. A total of 610 (43.5%) patients were diagnosed as having ascending subcutaneous thrombophlebitis of the femur. Of these, a total of 592 (97%) patients were operated on within 1-48 hours following admission. We propose a methodology of comprehensive conservative treatment with the use of Antistax in a double dose and alternating pneumocompression with elevated pressure in the cuffs.

Numerical Simulations of Inclusion Behavior in Gas-Stirred Ladles

NASA Astrophysics Data System (ADS)

Lou, Wentao; Zhu, Miaoyong

2013-06-01

A computation fluid dynamics-population balance model (CFD-PBM) coupled model has been proposed to investigate the bubbly plume flow and inclusion behavior including growth, size distribution, and removal in gas-stirred ladles, and some new and important phenomena and mechanisms were presented. For the bubbly plume flow, a modified k- ɛ model with extra source terms to account for the bubble-induced turbulence was adopted to model the turbulence, and the bubble turbulent dispersion force was taken into account to predict gas volume fraction distribution in the turbulent gas-stirred system. For inclusion behavior, the phenomena of inclusions turbulent random motion, bubbles wake, and slag eye forming on the molten steel surface were considered. In addition, the multiple mechanisms both that promote inclusion growth due to inclusion-inclusion collision caused by turbulent random motion, shear rate in turbulent eddy, and difference inclusion Stokes velocities, and the mechanisms that promote inclusion removal due to bubble-inclusion turbulence random collision, bubble-inclusion turbulent shear collision, bubble-inclusion buoyancy collision, inclusion own floatation near slag-metal interface, bubble wake capture, and wall adhesion were investigated. The importance of different mechanisms and total inclusion removal ratio under different conditions, and the distribution of inclusion number densities in ladle, were discussed and clarified. The results show that at a low gas flow rate, the inclusion growth is mainly attributed to both turbulent shear collision and Stokes collision, which is notably affected by the Stokes collision efficiency, and the inclusion removal is mainly attributed to the bubble-inclusion buoyancy collision and inclusion own floatation near slag-metal interface. At a higher gas flow rate, the inclusions appear as turbulence random motion in bubbly plume zone, and both the inclusion-inclusion and inclusion-bubble turbulent random collisions become important for inclusion growth and removal. With the increase of the gas flow rate, the total removal ratio increases, but when the gas flow rate exceeds 200 NL/min in 150-ton ladle, the total removal ration almost does not change. For the larger size inclusions, the number density in bubbly plume zone is less than that in the sidewall recirculation zones, but for the small size inclusions, the distribution of number density shows the opposite trend.

Effect of contact angle on the orientation, stability, and assembly of dense floating cubes.

PubMed

Daniello, Robert; Khan, Kashan; Donnell, Michael; Rothstein, Jonathan P

2014-02-01

In this paper, the effect of contact angle, density, and size on the orientation, stability, and assembly of floating cubes was investigated. All the cubes tested were more dense than water. Floatation occurred as a result of capillary stresses induced by deformation of the air-water interface. The advancing contact angle of the bare acrylic cubes was measured to be 85°. The contact angle of the cubes was increased by painting the cubes with a commercially available superhydrophobic paint to reach an advancing contact angle of 150°. Depending on their size, density, and contact angle, the cubes were observed to float in one of three primary orientations: edge up, vertex up, and face up. An experimental apparatus was built such that the sum of the gravitational force, buoyancy force, and capillary forces could be measured using a force transducer as a function of cube position as it was lowered through the air-water interface. Measurements showed that the maximum capillary forces were always experienced for the face up orientation. However, when floatation was possible in the vertex up orientation, it was found to be the most stable cube orientation because it had the lowest center of gravity. A series of theoretical predictions were performed for the cubes floating in each of the three primary orientations to calculate the net force on the cube. The theoretical predictions were found to match the experimental measurements well. A cube stability diagram of cube orientation as a function of cube contact angle and size was prepared from the predictions of theory and found to match the experimental observations quite well. The assembly of cubes floating face up and vertex up were also studied for assemblies of two, three, and many cubes. Cubes floating face up were found to assemble face-to-face and form regular square lattice patterns with no free interface between cubes. Cubes floating vertex up were found to assemble in a variety of different arrangements including edge-to-edge, vertex-to-vertex, face-to-face, and vertex-to-face with the most probably assembly being edge-to-edge. Large numbers of vertex up cubes were found to pack with a distribution of orientations and alignments.

A comparative study on preprocessing techniques in diabetic retinopathy retinal images: illumination correction and contrast enhancement.

PubMed

Rasta, Seyed Hossein; Partovi, Mahsa Eisazadeh; Seyedarabi, Hadi; Javadzadeh, Alireza

2015-01-01

To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest Coefficients of variations in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low Coefficients of variations. The contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as CLAHE, for fundus images presented good potentials in enhancing the vasculature segmentation.

Ignition of an organic water-coal fuel droplet floating in a heated-air flow

NASA Astrophysics Data System (ADS)

Valiullin, T. R.; Strizhak, P. A.; Shevyrev, S. A.; Bogomolov, A. R.

2017-01-01

Ignition of an organic water-coal fuel (CWSP) droplet floating in a heated-air flow has been studied experimentally. Rank B2 brown-coal particles with a size of 100 μm, used crankcase Total oil, water, and a plasticizer were used as the main CWSP components. A dedicated quartz-glass chamber has been designed with inlet and outlet elements made as truncated cones connected via a cylindrical ring. The cones were used to shape an oxidizer flow with a temperature of 500-830 K and a flow velocity of 0.5-5.0 m/s. A technique that uses a coordinate-positioning gear, a nichrome thread, and a cutter element has been developed for discharging CWSP droplets into the working zone of the chamber. Droplets with an initial size of 0.4 to 2.0 mm were used. Conditions have been determined for a droplet to float in the oxidizer flow long enough for the sustainable droplet burning to be initiated. Typical stages and integral ignition characteristics have been established. The integral parameters (ignition-delay times) of the examined processes have been compared to the results of experiments with CWSP droplets suspended on the junction of a quick-response thermocouple. It has been shown that floating fuel droplets ignite much quicker than the ones that sit still on the thermocouple due to rotation of an CWSP droplet in the oxidizer flow, more uniform heating of the droplet, and lack of heat drainage towards the droplet center. High-speed video recording of the peculiarities of floatation of a burning fuel droplet makes it possible to complement the existing models of water-coal fuel burning. The results can be used for a more substantiated modeling of furnace CWSP burning with the ANSYS, Fluent, and Sigma-Flow software packages.

[Surveillance on the prevalence of soil-transmitted nematode infection in Fujian in 2006-2010].

PubMed

Chen, Bao-jian; Li, Li-sha; Zhang, Rong-yan; Li, Yan-rong; Zhang, Zhi-fang; Zheng, Guo-bin; Fang, Yan-yan; Lin, Chen-xin; Jiang, Dian-wei

2012-02-29

To analyze the prevalent trend of soil-transmitted nematode infection in Fujian Province during the past 5 year surveillance and evaluate the control effect. From 2006 to 2010, fecal samples of the inhabitants of 3 years old and above were collected every November and examined for intestinal helminth eggs by the modified Kato s thick smear technique at the 2 surveillance sites: Punan village of Zhangzhou and Gushan village of Shaowu. Cellophane tapes were used to detect pinworm eggs for children aged 3-12. Soil samples were also collected from vegetable field, lavatory, courtyard and kitchen of 20 randomly selected families (in 2 villages) each with stool egg-positive findings and examined for ascaris eggs by a modified saturated sodium nitrate floatation method. The prevalence of soil-transmitted nematode infection at the surveillance sites decreased from 45.3% (946/2087) in 2006 to 15.1% (226/1494) in 2010, with a reduction of 66.6%. Among the infected subjects, hookworm infection occupied 75%-85%, while ascaris or trichuris infections each accounted for less than 10%. In terms of infection intensity, 65.2%-85.5% of the hookworm infection was light, and majority of the infected subjects were farmers. The pinworm prevalence in children were still high although it had dropped down from 46.1% (140/304) in 2006 to 29.8% (36/121) in 2010, declined by 35.4%. In the 5 years, totally 400 soil samples from 100 families were examined and 21 samples were found ascaris egg positive with viable eggs in only one sample. The 5 year surveillance reveals a decreasing trend of the soil-transmitted nematode prevalence but shows a relatively high hookworm infection rate in the population and pinworm infection in children.

[Comprehensive monitoring of cerebral haemodynamics during surgical interventions on brachiocephalic arteries].

PubMed

Ignat'ev, I M; Bredikhin, R A; Falina, T G; Vinogradova, V V; Khismatullina, L I

2010-01-01

The authors analysed a total of 152 surgical interventions on the brachiocephalic arteries (BCAs) performed in 142 patients. All the patients were subjected to intraoperative monitoring of cerebral haemodynamics by means of transcranial Doppler (TCD) ultrasonography simultaneously accompanied by electroencephalography (EEG). Additionally, the state of the reconstructed carotid arteries was controlled by means of ultrasonographic duplex scanning (USDS). Comparing the findings of the TCD recording and EEG made it possible to single out 5 groups of the operated patients. The EEG technique turned out to have more informative value as compared with TCD ultrasonography in determining the degree of cerebral ischaemia during clamping of the carotid arteries (CAs). Nine (5.9%) patients demonstrated lower tolerance of the brain to ischaemia, and the operation on the BCA was performed with the use of a temporal intraluminal bypass graft. Microembolic signals (MES) were registered in 54.6% of cases. Single MES were detected in six patients, sporadic MES--in 53, and multiple MES--in 24. Mention should be made that the--MES associated with the placement of the bypass graft appeared to be multiple and were registered in all the operated patients. Diffusion-weighted magnetic resonance tomography revealed fresh foci of lacunar cerebral infarctions in 14 (25%) of the 56 patients thus examined. Intraoperative USDS of the reconstructed carotid arteries revealed floatation of the residual remnants of the intima in two patients, which was the cause of a repeat intervention. Combined monitoring of cerebral haemodynamics makes it possible to timely prevent cerebral ischaemia, to narrow the indications for placement of an intraluminal bypass graft, and to dramatically decrease the rate of postoperative complications.

QbD-Oriented Development and Characterization of Effervescent Floating-Bioadhesive Tablets of Cefuroxime Axetil.

PubMed

Bansal, Sanjay; Beg, Sarwar; Garg, Babita; Asthana, Abhay; Asthana, Gyati S; Singh, Bhupinder

2016-10-01

The objective of the present studies was systematic development of floating-bioadhesive gastroretentive tablets of cefuroxime axetil employing rational blend of hydrophilic polymers for attaining controlled release drug delivery. As per the QbD-based approach, the patient-centric target product profile and quality attributes of tablet were earmarked, and preliminary studies were conducted for screening the suitability of type of polymers, polymer ratio, granulation technique, and granulation time for formulation of tablets. A face-centered cubic design (FCCD) was employed for optimization of the critical material attributes, i.e., concentration of release controlling polymers, PEO 303 and HPMC K100 LV CR, and evaluating in vitro buoyancy, drug release, and ex vivo mucoadhesion strength. The optimized formulation was embarked upon through numerical optimization, which yield excellent floatation characteristic with drug release control (i.e., T 60% > 6 h) and bioadhesion strength. Drug-excipient compatibility studies through FTIR and P-XRD revealed the absence of any interaction between the drug and polymers. In vivo evaluation of the gastroretentive characteristics through X-ray imaging and in vivo pharmacokinetic studies in rabbits revealed significant extension in the rate of drug absorption (i.e., T max, K a, and MRT) from the optimized tablet formulation as compared to the marketed formulation. Successful establishment of various levels of in vitro/in vivo correlations (IVIVC) substantiated high degree of prognostic ability of in vitro dissolution conditions in predicting the in vivo performance. In a nutshell, the studies demonstrate successful development of the once-a-day gastroretentive formulations of cefuroxime axetil with controlled drug release profile and improved compliance.

Efficacy of Broadline® spot-on against Aelurostrongylus abstrusus and Troglostrongylus brevior lungworms in naturally infected cats from Italy.

PubMed

Giannelli, Alessio; Brianti, Emanuele; Varcasia, Antonio; Colella, Vito; Tamponi, Claudia; Di Paola, Giancarlo; Knaus, Martin; Halos, Lénaïg; Beugnet, Frederic; Otranto, Domenico

2015-04-30

The increasing reports of Aelurostrongylus abstrusus infection and the new information on Troglostrongylus brevior have spurred the interest of the scientific community towards the research of pharmaceutical compounds effective against both pathogens. A novel topical combination of fipronil, (S)-methoprene, eprinomectin and praziquantel (Broadline®, Merial) has been released for the treatment of a variety of feline parasitic infections. The present study reports the efficacy of this spot-on in treating cats naturally infected by feline lungworms. Client owned cats (n=191) were enrolled from three geographical areas of Italy and faecal samples were examined by floatation and Baermann techniques. Twenty-three individuals were positive for L1 of A. abstrusus (n=18) or T. brevior (n=3) or for both species (n=2) and they were topically treated with Broadline®. Seventeen of them were also concomitantly infected by other parasites. Four weeks after treatment, faecal samples were collected and examined to assess the efficacy of a single administration of the product. Based on lungworm larvae counts, the efficacy of the treatment was 90.5% or 100% for A. abstrusus or T. brevior, respectively. Cats released significantly lower amounts of lungworm larvae after treatment compared to pre-treatment (p<0.0001). All but three cats were negative for other nematodes after treatment and all cats recovered from respiratory signs. Results of this study indicate that a single administration of the topical combination fipronil, (S)-methoprene, eprinomectin and praziquantel is effective and safe for the treatment of A. abstrusus and/or T. brevior infections in cats living under field conditions. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

QbD-enabled systematic development of gastroretentive multiple-unit microballoons of itopride hydrochloride.

PubMed

Bansal, Sanjay; Beg, Sarwar; Asthana, Abhay; Garg, Babita; Asthana, Gyati Shilakari; Kapil, Rishi; Singh, Bhupinder

2016-01-01

The objectives of present studies were to develop the systematically optimized multiple-unit gastroretentive microballoons, i.e. hollow microspheres of itopride hydrochloride (ITH) employing quality by design (QbD)-based approach. Initially, the patient-centric QTPP and CQAs were earmarked, and preliminary studies were conducted to screen the suitable polymer, solvent, solvent ratio, pH and temperature conditions. Microspheres were prepared by non-aqueous solvent evaporation method employing Eudragit S-100. Risk assessment studies carried out by constructing Ishikawa cause-effect fish-bone diagram, and techniques like risk estimation matrix (REM) and failure mode effect analysis (FMEA) facilitated the selection of plausible factors affecting the drug product CQAs, i.e. percent yield, entrapment efficiency (EE) and percent buoyancy. A 3(3) Box-Behnken design (BBD) was employed for optimizing CMAs and CPPs selected during factor screening studies employing Taguchi design, i.e. drug-polymer ratio (X1), stirring temperature (X2) and stirring speed (X3). The hollow microspheres, as per BBD, were evaluated for EE, particle size and drug release characteristics. The optimum formulation was embarked upon using numerical desirability function yielding excellent floatation characteristics along with adequate drug release control. Drug-excipient compatibility studies employing FT-IR, DSC and powder XRD revealed absence of significant interaction among the formulation excipients. The SEM studies on the optimized formulation showed hollow and spherical nature of the prepared microspheres. In vivo X-ray imaging studies in rabbits confirmed the buoyant nature of the hollow microspheres for 8 h in the upper GI tract. In a nutshell, the current investigations report the successful development of gastroretentive floating microspheres for once-a-day administration of ITH.

Anthelmintic utilisation practices and prevalence of gastrointestinal helminth infections in sheep kept in the urban and peri-urban areas of Bishoftu Town.

PubMed

Datiko, Jallale; Terefe, Getachew; Bekele, Jemere

2013-02-01

Assessment of the anthelmintic (AH) utilisation practices and estimation of the prevalence of gastrointestinal helminth infections in sheep were carried out from November 2010 to April 2011 in urban and peri-urban areas of Bishoftu Town, central Ethiopia. A structured questionnaire was employed to assess the AH utilisation practices in sheep of 310 owners/households, while floatation and sedimentation techniques were used to study the prevalence of helminth infections. Faecal examinations revealed that 53.9 % of sheep harboured gastrointestinal helminth infections with a high frequency due to strongyles (77.3 %). The questionnaire survey revealed that sources of AH for sheep were government and private veterinary clinics for 98.5 % of urban and 65.4 % peri-urban respondents. In peri-urban areas, AH were also purchased from open markets and illegal dealers. Albendazole was the most common (75.5 %) drug used in sheep followed by ivermectin (18.7 %) and tetramisole (5.8 %). The criteria for selecting AH were: prescription by veterinarians (51.6 %), efficacy (31.9 %), price (12.3 %) and arbitrary reasons (4.2 %). Treatment frequency was minimal with 51.3, 32.3 and 15.8 % of the owners treating their sheep once, twice and less than once per year, respectively. Treatments mainly depended on manifestations of general (45.8 %) and digestive (23.3 %) symptoms. Irrespective of the body weight of the sheep, albendazole was the only drug reported to be given at half bolus/sheep (14.1 %). Owing to this practice, albendazole faces the risk of reduced efficacy or AH resistance due to its wide spread utilisation, handling by untrained personnel and suspected underdosage, which altogether support the perception of sheep owners on its lower effect on the performance of treated sheep.

Combining Vector Quantization and Histogram Equalization.

ERIC Educational Resources Information Center

Cosman, Pamela C.; And Others

1992-01-01

Discussion of contrast enhancement techniques focuses on the use of histogram equalization with a data compression technique, i.e., tree-structured vector quantization. The enhancement technique of intensity windowing is described, and the use of enhancement techniques for medical images is explained, including adaptive histogram equalization.…

A Comparative Study on Preprocessing Techniques in Diabetic Retinopathy Retinal Images: Illumination Correction and Contrast Enhancement

PubMed Central

Rasta, Seyed Hossein; Partovi, Mahsa Eisazadeh; Seyedarabi, Hadi; Javadzadeh, Alireza

2015-01-01

To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest Coefficients of variations in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low Coefficients of variations. The contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as CLAHE, for fundus images presented good potentials in enhancing the vasculature segmentation. PMID:25709940

Microplastic concentrations in beach sediments along the German Baltic coast.

PubMed

Stolte, Andrea; Forster, Stefan; Gerdts, Gunnar; Schubert, Hendrik

2015-10-15

The contamination with microplastic particles and fibres was evaluated on beaches along the German Baltic coast. Sediments were sampled near the Warnow and Oder/Peene estuaries, on Rügen island and along the Rostock coast to derive possible entry pathways. Seasonal variations were monitored along the Rostock coast from March to July 2014. After density separation in saline solution, floating particles were found to be dominated by sand grains. Water surface tension is shown to be sufficient to explain floatation of grains with sizes less than 1.5mm. Selecting intensely coloured particles and fibres, we find lower limits of the microplastic concentrations of 0-7 particles/kg and 2-11 fibres/kg dry sediment. The largest microplastic contaminations are measured at the Peene outlet into the Baltic Sea and in the North Sea Jade Bay. City discharges, industrial production sites, fishing activity and tourism are the most likely sources for the highest microplastic concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Suspended Microplastics in the Surface Water of the Yangtze Estuary System, China: First Observations on Occurrence, Distribution

NASA Astrophysics Data System (ADS)

Zhao, S.

2014-12-01

Levels of microplastics (MPs) in China are completely unknown. Here suspended MPs were characterized quantitatively and qualitatively for the Yangtze Estuary and East China Sea. MPs were extracted via a floatation method. MPs were then counted and categorized according to shape and size under a dissecting microscope. The MP densities were 4137.3±2461.5 and 0.167±0.138 n/m3 in the estuarine and the sea waters, respectively. Plastic abundances varied strongly in the estuary. Higher density in the C transect corroborated that rivers were the important sources of MP to the marine environment. MPs (0.5-5mm) constituted more than 90% of total plastics. Plastic particles (> 5 mm) were observed with a maximum size of 12.46 mm. The most frequent plastics were fibres, followed by granules and films. Plastic spherules occurred sparsely. Transparent and coloured plastics comprised the majority of the particle colours. This study provides clues in understanding MPs fate and potential source.

Boundary condition of grounding lines prior to collapse, Larsen-B Ice Shelf, Antarctica.

PubMed

Rebesco, M; Domack, E; Zgur, F; Lavoie, C; Leventer, A; Brachfeld, S; Willmott, V; Halverson, G; Truffer, M; Scambos, T; Smith, J; Pettit, E

2014-09-12

Grounding zones, where ice sheets transition between resting on bedrock to full floatation, help regulate ice flow. Exposure of the sea floor by the 2002 Larsen-B Ice Shelf collapse allowed detailed morphologic mapping and sampling of the embayment sea floor. Marine geophysical data collected in 2006 reveal a large, arcuate, complex grounding zone sediment system at the front of Crane Fjord. Radiocarbon-constrained chronologies from marine sediment cores indicate loss of ice contact with the bed at this site about 12,000 years ago. Previous studies and morphologic mapping of the fjord suggest that the Crane Glacier grounding zone was well within the fjord before 2002 and did not retreat further until after the ice shelf collapse. This implies that the 2002 Larsen-B Ice Shelf collapse likely was a response to surface warming rather than to grounding zone instability, strengthening the idea that surface processes controlled the disintegration of the Larsen Ice Shelf. Copyright © 2014, American Association for the Advancement of Science.

Deployment, release and recovery of ocean riser pipes

DOEpatents

Person, Abraham; Wetmore, Sherman B.; McNary, James F.

1980-11-18

An ocean thermal energy conversion facility includes a long pipe assembly which is supported at its upper end by the hull of the floating facility. Cold water flows to the facility from deep in the ocean. The pipe assembly comprises an elongate pipe construction and a weight connected to the lower end of the construction by a line of selected length. A floatation collar is connected to the construction at its upper end to cause the construction to have positive buoyancy and a center of buoyancy closer to the upper end of the construction than its center of mass. The weight renders the entire pipe assembly negatively buoyant. In the event that support of the pipe assembly should be lost, as by release of the assembly from the facility hull in an emergency, the assembly sinks to the ocean floor where it is moored by the weight. The pipe construction floats submerged above the ocean floor in a substantially vertical attitude which facilitates recovery of the assembly.

Public health risk assessment associated with heavy metal and arsenic exposure near an abandoned mine (Kirki, Greece).

PubMed

Nikolaidis, Christos; Orfanidis, Moysis; Hauri, Dimitri; Mylonas, Stratos; Constantinidis, Theodore

2013-12-01

The 'Agios Philippos' lead-zinc mine in the Kirki region (NE Greece) is now closed, but its legacy of heavy metal contamination remains at the site. At present, management of the contaminated land is of major concern. The area is in a reclamation process and requires immediate remediation action, whereas human risks need to be carefully evaluated. In order to assess these risks, samples from around the mine were collected and analyzed and a scenario involving the oral, dermal, and inhaled doses of arsenic and heavy metals was formulated. A Monte Carlo approach was undertaken, in order to model the average daily dose and quantify the corresponding hazard index and cancer risk. A toxicological risk was associated with samples collected in the vicinity of the mine (floatation, mine tailings) and a pronounced carcinogenic risk for arsenic was evident at the broader occupational/environmental setting. These findings urge for immediate rehabilitation actions that will mitigate population exposures and promote long-term environmental safety in the area.

Design and Implementation of a new Autonomous Sensor Fish to Support Advanced Hydropower Development

DOE PAGES

Deng, Zhiqun; Lu, Jun; Myjak, Mitchell J.; ...

2014-11-04

Acceleration in development of additional conventional hydropower requires tools and methods to perform laboratory and in-field validation of turbine performance and fish passage claims. The new-generation Sensor Fish has been developed with more capabilities to accommodate a wider range of users over a wider range of turbine designs and operating environments. It provides in situ measurements of three dimensional (3D) accelerations, 3D rotational velocities, 3D orientation, pressure, and temperature at a sampling frequency of 2048 Hz. It also has an automatic floatation system and built-in radio frequency transmitter for recovery. The relative errors of the pressure, acceleration and rotational velocitymore » were within ±2%, ±5%, and ±5%, respectively. The accuracy of orientation was within ±4° and accuracy of temperature was ±2°C. It is being deployed to evaluate the biological effects of turbines or other hydraulic structures in several countries.« less

Plastic debris and microplastics along the beaches of the Strait of Hormuz, Persian Gulf.

PubMed

Naji, Abolfazl; Esmaili, Zinat; Khan, Farhan R

2017-01-30

Currently little is known about the prevalence of plastics and microplastics (MPs) in the Persian Gulf. Five sampling stations were selected along the Strait of Hormuz (Iran) that exhibited different levels of industrialization and urbanization, and included a marine protected area. Debris was observed and sediments were collected for MPs extraction via fluidization/floatation methodology. The order of MP abundance (par/kg) generally reflected the level of anthropogenic activity: Bostanu (1258±291)>Gorsozan (122±23)>Khor-e-Yekshabeh (26±6)>Suru (14±4)>Khor-e-Azini (2±1). Across all sites fibers dominated (83%, 11% film, 6% fragments). FT-IR analysis showed polyethylene (PE), nylon, and PET (polyethylene terephthalate) were the commonly recovered polymers. Likely sources include beach debris, discarded fishing gear, and urban and industrial outflows that contain fibers from clothes. This study provides a 'snapshot' of MP pollution and longitudinal studies are required to fully understand plastic contamination in the region. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fracture, inflation and floatation embolisation of PTCA balloon

PubMed Central

O'Neill, Louisa; Sowbhaga, Vinay; Owens, Patrick

2015-01-01

This case outlines an unusual complication of coronary intervention, the likely mechanisms leading to this and possible retrieval options. It is the first case to the best of our knowledge reporting this complication. A 78-year-old Caucasian man underwent coronary stenting. During the procedure kinking and subsequent fracture of a non-compliant percutaneous transluminal coronary angioplasty (PTCA) balloon occurred. Injection of contrast down the guide to opacify the coronary arteries resulted in ‘inflation’ of the balloon with air, and embolisation of the inflated balloon into the proximal left anterior descending artery. The embolised balloon was retrieved by removal of the guide catheter and wire as a unit. The patient had a good angiographic outcome. This case highlights risks associated with usage of kinked balloons catheters, and describes for the first time to our knowledge, the inflation of a PTCA balloon with air from its shaft within the catheter, causing ‘floatation’ embolisation into the coronary artery. PMID:25576524

A simple method to obtain low density marrow cells for human marrow transplantation.

PubMed

de Witte, T; Plas, A; Vet, J; Koekman, E; Preyers, F; Wessels, J

1987-01-01

Removal of more than 99% of the erythrocytes and 74% of the nucleated cells from marrow grafts was achieved by density floatation separation in Percoll gradients with a density of 1.070 g/ml in eight 250-ml tubes, containing up to 3 X 10(9) nucleated cells per gradient. More than 90% of the myeloid and erythroid progenitor cells were recovered in the low density fraction. It appeared mandatory to use a centrifuge with the possibility of a gradual acceleration and deceleration. Twenty-five patients received a marrow graft from a histocompatible sibling after additional lymphocyte depletion by counterflow centrifugation, and 5 patients with T lymphoblastic malignancies received an autograft after in vitro purging with immunotoxins. All evaluable patients engrafted within normal limits, except 1 patient with an autoimmune pancytopenia who responded to steroids and 1 patient with a CMV infection. Four patients died too early for complete evaluation. The described separation method is easy, cheap and requires only 2 h for the complete processing of a marrow graft.

Osmium isotope and highly siderophile element systematics of the lunar crust

NASA Astrophysics Data System (ADS)

Day, James M. D.; Walker, Richard J.; James, Odette B.; Puchtel, Igor S.

2010-01-01

Coupled 187Os/ 188Os and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for pristine lunar crustal rocks 60025, 62255, 65315 (ferroan anorthosites, FAN) and 76535, 78235, 77215 and a norite clast in 15455 (magnesian-suite rocks, MGS). Osmium isotopes permit more refined discrimination than previously possible of samples that have been contaminated by meteoritic additions and the new results show that some rocks, previously identified as pristine, contain meteorite-derived HSE. Low HSE abundances in FAN and MGS rocks are consistent with derivation from a strongly HSE-depleted lunar mantle. At the time of formation, the lunar floatation crust, represented by FAN, had 1.4 ± 0.3 pg g - 1 Os, 1.5 ± 0.6 pg g - 1 Ir, 6.8 ± 2.7 pg g - 1 Ru, 16 ± 15 pg g - 1 Pt, 33 ± 30 pg g - 1 Pd and 0.29 ± 0.10 pg g - 1 Re (˜ 0.00002 × CI) and Re/Os ratios that were modestly elevated ( 187Re/ 188Os = 0.6 to 1.7) relative to CI chondrites. MGS samples are, on average, characterised by more elevated HSE abundances (˜ 0.00007 × CI) compared with FAN. This either reflects contrasting mantle-source HSE characteristics of FAN and MGS rocks, or different mantle-crust HSE fractionation behaviour during production of these lithologies. Previous studies of lunar impact-melt rocks have identified possible elevated Ru and Pd in lunar crustal target rocks. The new results provide no supporting evidence for such enrichments. If maximum estimates for HSE in the lunar mantle are compared with FAN and MGS averages, crust-mantle concentration ratios ( D-values) must be ≤ 0.3. Such D-values are broadly similar to those estimated for partitioning between the terrestrial crust and upper mantle, with the notable exception of Re. Given the presumably completely different mode of origin for the primary lunar floatation crust and tertiary terrestrial continental crust, the potential similarities in crust-mantle HSE partitioning for the Earth and Moon are somewhat surprising. Low HSE abundances in the lunar crust, coupled with estimates of HSE concentrations in the lunar mantle implies there may be a 'missing component' of late-accreted materials (as much as 95%) to the Moon if the Earth/Moon mass-flux estimates are correct and terrestrial mantle HSE abundances were established by late accretion.

Osmium isotope and highly siderophile element systematics of the lunar crust

USGS Publications Warehouse

Day, J.M.D.; Walker, R.J.; James, O.B.; Puchtel, I.S.

2010-01-01

Coupled 187Os/188Os and highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundance data are reported for pristine lunar crustal rocks 60025, 62255, 65315 (ferroan anorthosites, FAN) and 76535, 78235, 77215 and a norite clast in 15455 (magnesian-suite rocks, MGS). Osmium isotopes permit more refined discrimination than previously possible of samples that have been contaminated by meteoritic additions and the new results show that some rocks, previously identified as pristine, contain meteorite-derived HSE. Low HSE abundances in FAN and MGS rocks are consistent with derivation from a strongly HSE-depleted lunar mantle. At the time of formation, the lunar floatation crust, represented by FAN, had 1.4 ?? 0.3 pg g- 1 Os, 1.5 ?? 0.6 pg g- 1 Ir, 6.8 ?? 2.7 pg g- 1 Ru, 16 ?? 15 pg g- 1 Pt, 33 ?? 30 pg g- 1 Pd and 0.29 ?? 0.10 pg g- 1 Re (??? 0.00002 ?? CI) and Re/Os ratios that were modestly elevated (187Re/188Os = 0.6 to 1.7) relative to CI chondrites. MGS samples are, on average, characterised by more elevated HSE abundances (??? 0.00007 ?? CI) compared with FAN. This either reflects contrasting mantle-source HSE characteristics of FAN and MGS rocks, or different mantle-crust HSE fractionation behaviour during production of these lithologies. Previous studies of lunar impact-melt rocks have identified possible elevated Ru and Pd in lunar crustal target rocks. The new results provide no supporting evidence for such enrichments. If maximum estimates for HSE in the lunar mantle are compared with FAN and MGS averages, crust-mantle concentration ratios (D-values) must be ??? 0.3. Such D-values are broadly similar to those estimated for partitioning between the terrestrial crust and upper mantle, with the notable exception of Re. Given the presumably completely different mode of origin for the primary lunar floatation crust and tertiary terrestrial continental crust, the potential similarities in crust-mantle HSE partitioning for the Earth and Moon are somewhat surprising. Low HSE abundances in the lunar crust, coupled with estimates of HSE concentrations in the lunar mantle implies there may be a 'missing component' of late-accreted materials (as much as 95%) to the Moon if the Earth/Moon mass-flux estimates are correct and terrestrial mantle HSE abundances were established by late accretion. ?? 2009 Elsevier B.V. All rights reserved.

Eliminating the Attentional Blink through Binaural Beats: A Case for Tailored Cognitive Enhancement.

PubMed

Reedijk, Susan A; Bolders, Anne; Colzato, Lorenza S; Hommel, Bernhard

2015-01-01

Enhancing human cognitive performance is a topic that continues to spark scientific interest. Studies into cognitive-enhancement techniques often fail to take inter-individual differences into account, however, which leads to underestimation of the effectiveness of these techniques. The current study investigated the effect of binaural beats, a cognitive-enhancement technique, on attentional control in an attentional blink (AB) task. As predicted from a neurocognitive approach to cognitive control, high-frequency binaural beats eliminated the AB, but only in individuals with low spontaneous eye-blink rates (indicating low striatal dopamine levels). This suggests that the way in which cognitive-enhancement techniques, such as binaural beats, affect cognitive performance depends on inter-individual differences.

"Relative CIR": an image enhancement and visualization technique

USGS Publications Warehouse

Fleming, Michael D.

1993-01-01

Many techniques exist to spectrally and spatially enhance digital multispectral scanner data. One technique enhances an image while keeping the colors as they would appear in a color-infrared (CIR) image. This "relative CIR" technique generates an image that is both spectrally and spatially enhanced, while displaying a maximum range of colors. The technique enables an interpreter to visualize either spectral or land cover classes by their relative CIR characteristics. A relative CIR image is generated by developed spectral statistics for each class in the classifications and then, using a nonparametric approach for spectral enhancement, the means of the classes for each band are ranked. A 3 by 3 pixel smoothing filter is applied to the classification for spatial enhancement and the classes are mapped to the representative rank for each band. Practical applications of the technique include displaying an image classification product as a CIR image that was not derived directly from a spectral image, visualizing how a land cover classification would look as a CIR image, and displaying a spectral classification or intermediate product that will be used to label spectral classes.

Resolution enhancement techniques in microscopy

NASA Astrophysics Data System (ADS)

Cremer, Christoph; Masters, Barry R.

2013-05-01

We survey the history of resolution enhancement techniques in microscopy and their impact on current research in biomedicine. Often these techniques are labeled superresolution, or enhanced resolution microscopy, or light-optical nanoscopy. First, we introduce the development of diffraction theory in its relation to enhanced resolution; then we explore the foundations of resolution as expounded by the astronomers and the physicists and describe the conditions for which they apply. Then we elucidate Ernst Abbe's theory of optical formation in the microscope, and its experimental verification and dissemination to the world wide microscope communities. Second, we describe and compare the early techniques that can enhance the resolution of the microscope. Third, we present the historical development of various techniques that substantially enhance the optical resolution of the light microscope. These enhanced resolution techniques in their modern form constitute an active area of research with seminal applications in biology and medicine. Our historical survey of the field of resolution enhancement uncovers many examples of reinvention, rediscovery, and independent invention and development of similar proposals, concepts, techniques, and instruments. Attribution of credit is therefore confounded by the fact that for understandable reasons authors stress the achievements from their own research groups and sometimes obfuscate their contributions and the prior art of others. In some cases, attribution of credit is also made more complex by the fact that long term developments are difficult to allocate to a specific individual because of the many mutual connections often existing between sometimes fiercely competing, sometimes strongly collaborating groups. Since applications in biology and medicine have been a major driving force in the development of resolution enhancing approaches, we focus on the contribution of enhanced resolution to these fields.

A comparison of enhancement techniques for footwear impressions on dark and patterned fabrics.

PubMed

Farrugia, Kevin J; Bandey, Helen; Dawson, Lorna; Daéid, Niamh Nic

2013-11-01

The use of chemical enhancement techniques on porous substrates, such as fabrics, poses several challenges predominantly due to the occurrence of background staining and diffusion as well as visualization difficulties. A range of readily available chemical and lighting techniques were utilized to enhance footwear impressions made in blood, soil, and urine on dark and patterned fabrics. Footwear impressions were all prepared at a set force using a specifically built footwear rig. In most cases, results demonstrated that fluorescent chemical techniques were required for visualization as nonfluorescent techniques provided little or no contrast with the background. Occasionally, this contrast was improved by oblique lighting. Successful results were obtained for the enhancement of footwear impressions in blood; however, the enhancement of footwear impressions in urine and soil on dark and patterned fabrics was much more limited. The results demonstrate that visualization and fluorescent enhancement on porous substrates such as fabrics is possible. © 2013 American Academy of Forensic Sciences.

Effects of Enhancement Techniques on L2 Incidental Vocabulary Learning

ERIC Educational Resources Information Center

Duan, Shiping

2018-01-01

Enhancement Techniques are conducive to incidental vocabulary learning. This study investigated the effects of two types of enhancement techniques-multiple-choice glosses (MC) and L1 single-gloss (SG) on L2 incidental learning of new words and retention of them. A total of 89 university learners of English as a Foreign Language (EFL) were asked to…

Eliminating the Attentional Blink through Binaural Beats: A Case for Tailored Cognitive Enhancement

PubMed Central

Reedijk, Susan A.; Bolders, Anne; Colzato, Lorenza S.; Hommel, Bernhard

2015-01-01

Enhancing human cognitive performance is a topic that continues to spark scientific interest. Studies into cognitive-enhancement techniques often fail to take inter-individual differences into account, however, which leads to underestimation of the effectiveness of these techniques. The current study investigated the effect of binaural beats, a cognitive-enhancement technique, on attentional control in an attentional blink (AB) task. As predicted from a neurocognitive approach to cognitive control, high-frequency binaural beats eliminated the AB, but only in individuals with low spontaneous eye-blink rates (indicating low striatal dopamine levels). This suggests that the way in which cognitive-enhancement techniques, such as binaural beats, affect cognitive performance depends on inter-individual differences. PMID:26089802

Holographic radar imaging privacy techniques utilizing dual-frequency implementation

NASA Astrophysics Data System (ADS)

McMakin, Douglas L.; Hall, Thomas E.; Sheen, David M.

2008-04-01

Over the last 15 years, the Pacific Northwest National Laboratory has performed significant research and development activities to enhance the state of the art of holographic radar imaging systems to be used at security checkpoints for screening people for concealed threats hidden under their garments. These enhancement activities included improvements to privacy techniques to remove human features and providing automatic detection of body-worn concealed threats. The enhanced privacy and detection methods used both physical and software imaging techniques. The physical imaging techniques included polarization-diversity illumination and reception, dual-frequency implementation, and high-frequency imaging at 60 GHz. Software imaging techniques to enhance the privacy of the person under surveillance included extracting concealed threat artifacts from the imagery to automatically detect the threat. This paper will focus on physical privacy techniques using dual-frequency implementation.

Effects of Restricted Launch Conditions for the Enhancement of Bandwidth-Distance Product of Multimode Fiber Links

NASA Technical Reports Server (NTRS)

Andrawis, Alfred S.

2000-01-01

Several techniques had been proposed to enhance multimode fiber bandwidth-distance product. Single mode-to-multimode offset launch condition technique had been experimented with at Kennedy Space Center. Significant enhancement in multimode fiber link bandwidth is achieved using this technique. It is found that close to three-fold bandwidth enhancement can be achieved compared to standard zero offset launch technique. Moreover, significant reduction in modal noise has been observed as a function of offset launch displacement. However, significant reduction in the overall signal-to-noise ratio is also observed due to signal attenuation due to mode radiation from fiber core to its cladding.

Enhanced cell volume regulation: a key protective mechanism of ischemic preconditioning in rabbit ventricular myocytes.

PubMed

Diaz, Roberto J; Armstrong, Stephen C; Batthish, Michelle; Backx, Peter H; Ganote, Charles E; Wilson, Gregory J

2003-01-01

Accumulation of osmotically active metabolites, which create an osmotic gradient estimated at ~60 mOsM, and cell swelling are prominent features of ischemic myocardial cell death. This study tests the hypothesis that reduction of ischemic swelling by enhanced cell volume regulation is a key mechanism in the delay of ischemic myocardial cell death by ischemic preconditioning (IPC). Experimental protocols address whether: (i) IPC triggers a cell volume regulation mechanism that reduces cardiomyocyte swelling during subsequent index ischemia; (ii) this reduction in ischemic cell swelling is sufficient in magnitude to account for the IPC protection; (iii) the molecular mechanism that mediates IPC also mediates cell volume regulation. Two experimental models with rabbit ventricular myocytes were studied: freshly isolated pelleted myocytes and 48-h cultured myocytes. Myocytes were preconditioned either by distinct short simulated ischemia (SI)/simulated reperfusion protocols (IPC), or by subjecting myocytes to a pharmacological preconditioning (PPC) protocol (1 microM calyculin A, or 1 microM N(6)-2-(4-aminophenyl)ethyladenosine (APNEA), prior to subjecting them to either different durations of long SI or 30 min hypo-osmotic stress. Cell death (percent blue square myocytes) was monitored by trypan blue staining. Cell swelling was determined by either the bromododecane cell flotation assay (qualitative) or video/confocal microscopy (quantitative). Simulated ischemia induced myocyte swelling in both the models. In pelleted myocytes, IPC or PPC with either calyculin A or APNEA produced a marked reduction of ischemic cell swelling as determined by the cell floatation assay. In cultured myocytes, IPC substantially reduced ischemic cell swelling (P < 0.001). This IPC effect on ischemic cell swelling was related to an IPC and PPC (with APNEA) mediated triggering of cell volume regulatory decrease (RVD). IPC and APNEA also significantly (P < 0.001) reduced hypo-osmotic cell swelling. This IPC and APNEA effect was blocked by either adenosine receptor, PKC or Cl(-) channel inhibition. The osmolar equivalent for IPC protection approximated 50-60 mOsM, an osmotic gradient similar to the estimated ischemic osmotic load for preconditioned and non-preconditioned myocytes. The results suggest that cell volume regulation is a key mechanism that accounts for most of the IPC protection in cardiomyocytes.

An investigation into the enhancement of sea-spray exposed fingerprints on glass.

PubMed

Goldstone, S L; Francis, S C; Gardner, S J

2015-07-01

Fingerprints are considered one of the best forms of personal identification. While numerous enhancement techniques exist to develop fingerprints under various conditions, the enhancement of fingerprints exposed to sea spray aerosol (SSA) still remains problematic. 1056 fingerprints from four donors, using a depletion series and triplicate repeats, were deposited onto glass panels and exposed to SSA for 1 week and 1 month. Control prints were deposited in the same manner and left under laboratory conditions. All prints were enhanced using fingerprint enhancement techniques available to Forensic Police Officers and subsequently examined for identifiability by a Fingerprint Expert. Significantly fewer identifiable prints (p<0.01) were developed after exposure to SSA for 1 month (11%) compared to exposure for 1 week (69%) (compared to the control prints 99%) for all enhancement techniques. After 1 week's exposure, all techniques enhanced over 50% of prints, except SPR white (12%), with iron (III) oxide and Wetwop™ white producing over 90% identifiable prints. Only iron (III) oxide, Wetwop™ white and SPR black returned any identifiable prints following 1 month's SSA exposure. Iron (III) oxide being significantly better (p<0.01, 67%) than the other techniques. Iron (III) oxide suspension and Wetwop™ white were found to be superior at enhancing prints at both SSA exposure times. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Differential Association of the Na+/H+ Exchanger Regulatory Factor (NHERF) Family of Adaptor Proteins with the Raft-and the Non-Raft Brush Border Membrane Fractions of NHE3

PubMed Central

Sultan, Ayesha; Luo, Min; Yu, Qin; Riederer, Brigitte; Xia, Weiliang; Chen, Mingmin; Lissner, Simone; Gessner, Johannes E.; Donowitz, Mark; Yun, C. Chris; deJonge, Hugo; Lamprecht, Georg; Seidler, Ursula

2014-01-01

Background/Aims Trafficking, brush border membrane (BBM) retention, and signal-specific regulation of the Na+/H+ exchanger NHE3 is regulated by the Na+/H+ Exchanger Regulatory Factor (NHERF) family of PDZ-adaptor proteins, which enable the formation of multiprotein complexes. It is unclear, however, what determines signal specificity of these NHERFs. Thus, we studied the association of NHE3, NHERF1 (EBP50), NHERF2 (E3KARP), and NHERF3 (PDZK1) with lipid rafts in murine small intestinal BBM. Methods Detergent resistant membranes (“lipid rafts”) were isolated by floatation of Triton X-incubated small intestinal BBM from a variety of knockout mouse strains in an Optiprep step gradient. Acid-activated NHE3 activity was measured fluorometrically in BCECF-loaded microdissected villi, or by assessment of CO2/HCO3− mediated increase in fluid absorption in perfused jejunal loops of anethetized mice. Results NHE3 was found to partially associate with lipid rafts in the native BBM, and NHE3 raft association had an impact on NHE3 transport activity and regulation in vivo. NHERF1, 2 and 3 were differentially distributed to rafts and non-rafts, with NHERF2 being most raft-associated and NHERF3 entirely non-raft associated. NHERF2 expression enhanced the localization of NHE3 to membrane rafts. The use of acid sphingomyelinase-deficient mice, which have altered membrane lipid as well as lipid raft composition, allowed us to test the validity of the lipid raft concept in vivo. Conclusions The differential association of the NHERFs with the raft-associated and the non-raft fraction of NHE3 in the brush border membrane is one component of the differential and signal-specific NHE3 regulation by the different NHERFs. PMID:24297041

Differential association of the Na+/H+ Exchanger Regulatory Factor (NHERF) family of adaptor proteins with the raft- and the non-raft brush border membrane fractions of NHE3.

PubMed

Sultan, Ayesha; Luo, Min; Yu, Qin; Riederer, Brigitte; Xia, Weiliang; Chen, Mingmin; Lissner, Simone; Gessner, Johannes E; Donowitz, Mark; Yun, C Chris; deJonge, Hugo; Lamprecht, Georg; Seidler, Ursula

2013-01-01

Trafficking, brush border membrane (BBM) retention, and signal-specific regulation of the Na+/H+ exchanger NHE3 is regulated by the Na+/H+ Exchanger Regulatory Factor (NHERF) family of PDZ-adaptor proteins, which enable the formation of multiprotein complexes. It is unclear, however, what determines signal specificity of these NHERFs. Thus, we studied the association of NHE3, NHERF1 (EBP50), NHERF2 (E3KARP), and NHERF3 (PDZK1) with lipid rafts in murine small intestinal BBM. Detergent resistant membranes ("lipid rafts") were isolated by floatation of Triton X-incubated small intestinal BBM from a variety of knockout mouse strains in an Optiprep step gradient. Acid-activated NHE3 activity was measured fluorometrically in BCECF-loaded microdissected villi, or by assessment of CO2/HCO3(-) mediated increase in fluid absorption in perfused jejunal loops of anethetized mice. NHE3 was found to partially associate with lipid rafts in the native BBM, and NHE3 raft association had an impact on NHE3 transport activity and regulation in vivo. NHERF1, 2 and 3 were differentially distributed to rafts and non-rafts, with NHERF2 being most raft-associated and NHERF3 entirely non-raft associated. NHERF2 expression enhanced the localization of NHE3 to membrane rafts. The use of acid sphingomyelinase-deficient mice, which have altered membrane lipid as well as lipid raft composition, allowed us to test the validity of the lipid raft concept in vivo. The differential association of the NHERFs with the raft-associated and the non-raft fraction of NHE3 in the brush border membrane is one component of the differential and signal-specific NHE3 regulation by the different NHERFs. © 2013 S. Karger AG, Basel.

Post-processing techniques to enhance reliability of assignment algorithm based performance measures.

DOT National Transportation Integrated Search

2011-01-01

This study develops an enhanced transportation planning framework by augmenting the sequential four-step : planning process with post-processing techniques. The post-processing techniques are incorporated through a feedback : mechanism and aim to imp...

Enhancing multi-spot structured illumination microscopy with fluorescence difference

NASA Astrophysics Data System (ADS)

Ward, Edward N.; Torkelsen, Frida H.; Pal, Robert

2018-03-01

Structured illumination microscopy is a super-resolution technique used extensively in biological research. However, this technique is limited in the maximum possible resolution increase. Here we report the results of simulations of a novel enhanced multi-spot structured illumination technique. This method combines the super-resolution technique of difference microscopy with structured illumination deconvolution. Initial results give at minimum a 1.4-fold increase in resolution over conventional structured illumination in a low-noise environment. This new technique also has the potential to be expanded to further enhance axial resolution with three-dimensional difference microscopy. The requirement for precise pattern determination in this technique also led to the development of a new pattern estimation algorithm which proved more efficient and reliable than other methods tested.

Effects of High Pressure ORE Grinding on the Efficiency of Flotation Operations

NASA Astrophysics Data System (ADS)

Saramak, Daniel; Krawczykowska, Aldona; Młynarczykowska, Anna

2014-10-01

This article discusses issues related to the impact of the high pressure comminution process on the efficiency of the copper ore flotation operations. HPGR technology improves the efficiency of mineral resource enrichment through a better liberation of useful components from waste rock as well as more efficient comminution of the material. Research programme included the run of a laboratory flotation process for HPGR crushing products at different levels of operating pressures and moisture content. The test results showed that products of the high-pressure grinding rolls achieved better recoveries in flotation processes and showed a higher grade of useful components in the flotation concentrate, in comparison to the ball mill products. Upgrading curves have also been marked in the following arrangement: the content of useful component in concentrate the floatation recovery. All upgrading curves for HPGR products had a more favourable course in comparison to the curves of conventionally grinded ore. The results also indicate that various values of flotation recoveries have been obtained depending on the machine operating parameters (i.e. the operating pressure), and selected feed properties (moisture).

Design and implementation of a new autonomous sensor fish to support advanced hydropower development.

PubMed

Deng, Z D; Lu, J; Myjak, M J; Martinez, J J; Tian, C; Morris, S J; Carlson, T J; Zhou, D; Hou, H

2014-11-01

Acceleration in development of additional conventional hydropower requires tools and methods to perform laboratory and in-field validation of turbine performance and fish passage claims. The new-generation Sensor Fish has been developed with more capabilities to accommodate a wider range of users over a broader range of turbine designs and operating environments. It provides in situ measurements of three-dimensional (3D) linear accelerations, 3D rotational velocities, 3D orientation, pressure, and temperature at a sampling frequency of 2048 Hz. It also has an automatic floatation system and built-in radio-frequency transmitter for recovery. The relative errors of the pressure, acceleration, and rotational velocity were within ±2%, ±5%, and ±5%, respectively. The accuracy of orientation was within ±4° and accuracy of temperature was ±2 °C. The new-generation Sensor Fish is becoming a major technology and being deployed for evaluating the conditions for fish passage of turbines or other hydraulic structures in both the United States and several other countries.

Contamination, distribution and pathogenicity of Toxocara canis and T. cati eggs from sandpits in Tokyo, Japan.

PubMed

Macuhova, K; Akao, N; Fujinami, Y; Kumagai, T; Ohta, N

2013-09-01

The contamination, distribution and pathogenicity of Toxocara canis and T. cati eggs in sandpits in the Tokyo metropolitan area, Japan, are described. A total of 34 sandpits were examined, 14 of which were contaminated with T. cati eggs, as assessed by the floatation method and polymerase chain reaction (PCR) analysis. Two naturally contaminated sandpits were investigated to determine the vertical and horizontal distribution of eggs, and an inverse relationship between the sand depth and number of eggs was observed. To examine the pathogenicity of the eggs, three ICR mice were inoculated with 300 eggs, which were recovered from sandpits. The mice exhibited eosinophilia in the peripheral blood and IgG antibody production in the sera after 3 weeks of infection. Most migrating larvae were recovered from carcasses, although three were found in the brains of two infected mice. These three larvae were determined to be T. canis by PCR, revealing that not only T. cati, but also T. canis eggs could be found in sandpits and, further, that eggs recovered from sandpits have the ability to invade a paratenic host.

Removal of organic compounds from shale gas flowback water.

PubMed

Butkovskyi, Andrii; Faber, Ann-Hélène; Wang, Yue; Grolle, Katja; Hofman-Caris, Roberta; Bruning, Harry; Van Wezel, Annemarie P; Rijnaarts, Huub H M

2018-07-01

Ozonation, sorption to granular activated carbon and aerobic degradation were compared as potential treatment methods for removal of dissolved organic carbon (DOC) fractions and selected organic compounds from shale gas flowback water after pre-treatment in dissolved air flotation unit. Flowback water was characterised by high chemical oxygen demand and DOC. Low molecular weight (LMW) acids and neutral compounds were the most abundant organic fractions, corresponding to 47% and 35% of DOC respectively. Ozonation did not change distribution of organic carbon fractions and concentrations of detected individual organic compounds significantly. Sorption to activated carbon targeted removal of individual organic compounds with molecular weight >115 Da, whereas LMW compounds remained largely unaffected. Aerobic degradation was responsible for removal of LMW compounds and partial ammonium removal, whereas formation of intermediates with molecular weight of 200-350 Da was observed. Combination of aerobic degradation for LMW organics removal with adsorption to activated carbon for removal of non-biodegradable organics is proposed to be implemented between pre-treatment (dissolved air floatation) and desalination (thermal or membrane desalination) steps. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Comparison of the Pitfall Trap, Winkler Extractor and Berlese Funnel for Sampling Ground-Dwelling Arthropods in Tropical Montane Cloud Forests

PubMed Central

Sabu, Thomas K.; Shiju, Raj T.; Vinod, KV.; Nithya, S.

2011-01-01

Little is known about the ground-dwelling arthropod diversity in tropical montane cloud forests (TMCF). Due to unique habitat conditions in TMCFs with continuously wet substrates and a waterlogged forest floor along with the innate biases of the pitfall trap, Berlese funnel and Winkler extractor are certain to make it difficult to choose the most appropriate method to sample the ground-dwelling arthropods in TMCFs. Among the three methods, the Winkler extractor was the most efficient method for quantitative data and pitfall trapping for qualitative data for most groups. Inclusion of floatation method as a complementary method along with the Winkler extractor would enable a comprehensive quantitative survey of ground-dwelling arthropods. Pitfall trapping is essential for both quantitative and qualitative sampling of Diplopoda, Opiliones, Orthoptera, and Diptera. The Winkler extractor was the best quantitative method for Psocoptera, Araneae, Isopoda, and Formicidae; and the Berlese funnel was best for Collembola and Chilopoda. For larval forms of different insect orders and the Acari, all the three methods were equally effective. PMID:21529148

Radio controlled release apparatus for animal data acquisition devices

DOEpatents

Stamps, James Frederick

2000-01-01

A novel apparatus for reliably and selectively releasing a data acquisition package from an animal for recovery. The data package comprises two parts: 1) an animal data acquisition device and 2) a co-located release apparatus. One embodiment, which is useful for land animals, the release apparatus includes two major components: 1) an electronics package, comprising a receiver; a decoder comparator, having at plurality of individually selectable codes; and an actuator circuit and 2) a release device, which can be a mechanical device, which acts to release the data package from the animal. To release a data package from a particular animal, a radio transmitter sends a coded signal which is decoded to determine if the code is valid for that animal data package. Having received a valid code, the release device is activated to release the data package from the animal for subsequent recovery. A second embodiment includes floatation means and is useful for releasing animal data acquisition devices attached to sea animals. This embodiment further provides for releasing a data package underwater by employing an acoustic signal.

Use of bioassays for testing soils and/or sediments contaminated by mining activities

NASA Astrophysics Data System (ADS)

Pérez-Sirvent, C.; Martínez-Sánchez, M. J.; García-Lorenzo, M. L.; Molina, J.

2009-04-01

Ecotoxicity tests measure the bioavailability of the contaminants and the effects of the chemically not measured toxic compounds on the members of the soil community. Therefore, ecotoxicological testing may be a useful approach for assessing the toxicity as a complement to chemical analysis. They are solid phase tests based on terrestrial methods and tests performed on water extracts using aquatic test protocols. The extent and degree of heavy metal contamination around mines may vary depending on geochemical characteristics, the mineralization of tailings, physico-chemical conditions and the processes used to extract metals. Portman Bay was subject to mining from the time of the Roman Empire to 1991 when the activity ceased. Since 1957, the wastes from mining operations were discharged directly into the sea. These wastes mainly consisted of clay, quartz, siderite, magnetite, remains of sphalerite, pyrite and galena and residues of the chemical reagents used in floatation. In our study two methods of environmental toxicological tests were compared and applied to sediments of the Portman Bay (SE, Spain): the standardized toxicological test based on inhibition of luminescence employing Microtox

Fatty-binding protein and galectin of Baylisascaris schroederi: Prokaryotic expression and preliminary evaluation of serodiagnostic potential

PubMed Central

Sun, Ying; Li, Yu; Wu, Yiran; Xiong, Lang; Li, Caiwu; Wang, Chengdong; Li, Desheng; Lan, Jingchao; Zhang, Zhihe; Jing, Bo; Gu, Xiaobing; Xie, Yue; Lai, Weimin; Peng, Xuerong

2017-01-01

Baylisascaris schroederi is a common parasite of captive giant pandas. The diagnosis of this ascariasis is normally carried out by a sedimentation-floatation method or PCR to detect eggs in feces, but neither method is suitable for early diagnosis. Fatty acid-binding protein (FABP) and galectin (GAL) exist in various animals and participate in important biology of parasites. Because of their good immunogenicity, they are seen as potential antigens for the diagnosis of parasitic diseases. In this study, we cloned and expressed recombinant FABP and GAL from B. schroederi (rBs-FABP and rBs-GAL) and developed indirect enzyme-linked immunosorbent assays (ELISAs) to evaluate their potential for diagnosing ascariasis in giant pandas. Immunolocalization showed that Bs-FABP and Bs-GAL were widely distributed in adult worms. The ELISA based on rBs-FABP showed sensitivity of 95.8% (23/24) and specificity of 100% (12/12), and that based on rBs-GAL had sensitivity of 91.7% (22/24) and specificity of 100% (12/12). PMID:28750056

Seasonality of Cryptosporidium oocyst detection in surface waters of Meru, Kenya as determined by two isolation methods followed by PCR

PubMed Central

Muchiri, John M.; Ascolillo, Luke; Mugambi, Mutuma; Mutwiri, Titus; Ward, Honorine D.; Naumova, Elena N.; Egorov, Andrey I.; Cohen, Seth; Else, James G.; Griffiths, Jeffrey K.

2009-01-01

Meru, Kenya has watersheds which are shared by wildlife, humans and domesticated animals. These surface waters can be contaminated by the waterborne pathogen Cryptosporidium. To quantify the seasonality and prevalence of Cryptosporidium in Meru regional surface waters, we used a calcium carbonate flocculation (CCF) and sucrose floatation method, and a filtration and immunomagnetic bead separation method, each of which used PCR for Cryptosporidium detection and genotyping. Monthly water samples were collected from January through June in 2003 and 2004, bracketing two April-May rainy seasons. We detected significant seasonality with 8 of 9 positive samples from May and June (p < 0.0014), which followed peak rainy season precipitation and includes some of the subsequent dry season. Six of 9 positive samples revealed C. parvum, and 3 contained C. andersoni. None contained C. hominis. Our results indicate that Meru surface waters are Cryptosporidium-contaminated at the end of rainy seasons, consistent with the timing of human infections reported by others from East Africa and contrasting with the onset of rainy season peak incidence reported from West Africa. PMID:18957776

Heat shock protein-containing exosomes in mid-trimester amniotic fluids.

PubMed

Asea, Alexzander; Jean-Pierre, Claudel; Kaur, Punit; Rao, Preethi; Linhares, Iara M; Skupski, Daniel; Witkin, Steven S

2008-10-01

Exosomes are multivesicular bodies formed by inverse membrane budding into the lumen of an endocytic compartment. Fusion with the plasma membrane leads to their release into the external milieu. The incorporation of heat shock proteins into exosomes has been associated with immune regulatory activity. We have examined whether heat shock protein-containing exosomes are present in mid-trimester amniotic fluid. Exosomes were isolated from mid-trimester amniotic fluids by sequential low-speed and high-speed centrifugation followed by sucrose density gradient centrifugation. Biochemical characterization included floatation pattern in sucrose gradients, acetylcholinesterase (AChE) activity and Western blot analysis for exosome-containing proteins. Exosomes were present in each of 23 amniotic fluids tested. They banded at a density of 1.17g/ml in sucrose gradients, were positive for AChE activity and contained tubulin, the inducible 72kDa heat shock protein, Hsp72 and the constitutively expressed heat shock protein, Hsc73; they were negative for calnexin. Exosome concentrations correlated positively with the number of pregnancies. Heat shock protein-containing exosomes are constituents of mid-trimester amniotic fluids and may contribute to immune regulation within the amniotic cavity.

Wet and wild: results from a pilot study assessing injuries among recreational water users in Western Australia.

PubMed

Pikora, T J; Braham, R; Hill, C; Mills, C

2011-06-01

To identify, describe and compare injuries among three water sport activities: kite surfing (KS), personal watercraft (PWC) and towed water sports (TWS). The study was a cross sectional, online survey. The setting was on Perth, Western Australia's popular beaches and riverbanks. Main outcome measures were number of injuries and level of severity; level of exposure and protection measures. Overall, 43% reported at least one injury in the past 12 months, a rate of 22.3 injuries per 100 h. Kite surfers were more likely to report an injury than PWC or TWS. One-half of injuries occurred while on the water. Most injuries were caused by landing awkwardly (56%) and/or trying new tricks (41%). Despite 90% of respondents having used at least one personal protective equipment (PPE) item, half (49%) reported always using a personal floatation device. This study provided information on KS, PWC and TWS injuries as well as a range of safety behaviours. It is recommended that these results form the basis of further research to reduce injury rates and encourage the use of PPE items.

Floating capsules containing alginate-based beads of salbutamol sulfate: In vitro-in vivo evaluations.

PubMed

Malakar, Jadupati; Datta, Prabir Kumar; Purakayastha, Saikat Das; Dey, Sanjay; Nayak, Amit Kumar

2014-03-01

The present study deals with the development and evaluations of stomach-specific floating capsules containing salbutamol sulfate-loaded oil-entrapped alginate-based beads. Salbutamol sulfate-loaded oil-entrapped beads were prepared and capsulated within hard gelatin capsules (size 1). The effects of HPMC K4M and potato starch weight masses on drug encapsulation efficiency (DEE) of beads and cumulative drug release at 10h (R10 h) from capsules was analyzed by 3(2) factorial design. The optimization results indicate increasing of DEE in the oil-entrapped beads and decreasing R10 h from capsules with increment of HPMC K4M and potato starch weight masses. The optimized formulation showed DEE of 70.02 ± 3.16% and R10 h of 56.96 ± 2.92%. These capsules showed floatation over 6h and sustained drug release over 10h in gastric pH (1.2). In vivo X-ray imaging study of optimized floating capsules in rabbits showed stomach-specific gastroretention over a prolonged period. Copyright © 2013 Elsevier B.V. All rights reserved.

Swarm Intelligence for Optimizing Hybridized Smoothing Filter in Image Edge Enhancement

NASA Astrophysics Data System (ADS)

Rao, B. Tirumala; Dehuri, S.; Dileep, M.; Vindhya, A.

In this modern era, image transmission and processing plays a major role. It would be impossible to retrieve information from satellite and medical images without the help of image processing techniques. Edge enhancement is an image processing step that enhances the edge contrast of an image or video in an attempt to improve its acutance. Edges are the representations of the discontinuities of image intensity functions. For processing these discontinuities in an image, a good edge enhancement technique is essential. The proposed work uses a new idea for edge enhancement using hybridized smoothening filters and we introduce a promising technique of obtaining best hybrid filter using swarm algorithms (Artificial Bee Colony (ABC), Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO)) to search for an optimal sequence of filters from among a set of rather simple, representative image processing filters. This paper deals with the analysis of the swarm intelligence techniques through the combination of hybrid filters generated by these algorithms for image edge enhancement.

Contrast-enhanced spectral mammography based on a photon-counting detector: quantitative accuracy and radiation dose

NASA Astrophysics Data System (ADS)

Lee, Seungwan; Kang, Sooncheol; Eom, Jisoo

2017-03-01

Contrast-enhanced mammography has been used to demonstrate functional information about a breast tumor by injecting contrast agents. However, a conventional technique with a single exposure degrades the efficiency of tumor detection due to structure overlapping. Dual-energy techniques with energy-integrating detectors (EIDs) also cause an increase of radiation dose and an inaccuracy of material decomposition due to the limitations of EIDs. On the other hands, spectral mammography with photon-counting detectors (PCDs) is able to resolve the issues induced by the conventional technique and EIDs using their energy-discrimination capabilities. In this study, the contrast-enhanced spectral mammography based on a PCD was implemented by using a polychromatic dual-energy model, and the proposed technique was compared with the dual-energy technique with an EID in terms of quantitative accuracy and radiation dose. The results showed that the proposed technique improved the quantitative accuracy as well as reduced radiation dose comparing to the dual-energy technique with an EID. The quantitative accuracy of the contrast-enhanced spectral mammography based on a PCD was slightly improved as a function of radiation dose. Therefore, the contrast-enhanced spectral mammography based on a PCD is able to provide useful information for detecting breast tumors and improving diagnostic accuracy.

Scanning angle Raman spectroscopy: Investigation of Raman scatter enhancement techniques for chemical analysis

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

Meyer, Matthew W.

2013-01-01

This thesis outlines advancements in Raman scatter enhancement techniques by applying evanescent fields, standing-waves (waveguides) and surface enhancements to increase the generated mean square electric field, which is directly related to the intensity of Raman scattering. These techniques are accomplished by employing scanning angle Raman spectroscopy and surface enhanced Raman spectroscopy. A 1064 nm multichannel Raman spectrometer is discussed for chemical analysis of lignin. Extending dispersive multichannel Raman spectroscopy to 1064 nm reduces the fluorescence interference that can mask the weaker Raman scattering. Overall, these techniques help address the major obstacles in Raman spectroscopy for chemical analysis, which include themore » inherently weak Raman cross section and susceptibility to fluorescence interference.« less

Microneedles as the technique of drug delivery enhancement in diverse organs and tissues.

PubMed

Rzhevskiy, Alexey S; Singh, Thakur Raghu Raj; Donnelly, Ryan F; Anissimov, Yuri G

2018-01-28

Microneedles is the technique of drug delivery enhancement, which was primarily designed for facilitating percutaneous drug delivery. Started from the development of simple solid microneedles, providing microporation of stratum corneum and therefore enhancement of topical drug delivery, for two decades the technique has progressed in various modifications such as hollow, coated, dissolving and hydrogel forming microneedles. In their turn, the modifications have resulted in new mechanisms of drug delivery enhancement and followed by the expansion of applicability range in terms of targeted tissues and organs. Thus, in addition to percutaneous drug delivery, microneedles have been considered as an efficient technique facilitating ocular, oral mucosal, gastrointestinal, ungual and vaginal drug administration. It is anticipated that the technique of microneedle-assisted drug delivery will soon become relevant for majority of organs and tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

A Comparison of the Multiscale Retinex With Other Image Enhancement Techniques

NASA Technical Reports Server (NTRS)

Rahman, Zia-Ur; Woodell, Glenn A.; Jobson, Daniel J.

1997-01-01

The multiscale retinex with color restoration (MSRCR) has shown itself to be a very versatile automatic image enhancement algorithm that simultaneously provides dynamic range compression, color constancy, and color rendition. A number of algorithms exist that provide one or more of these features, but not all. In this paper we compare the performance of the MSRCR with techniques that are widely used for image enhancement. Specifically, we compare the MSRCR with color adjustment methods such as gamma correction and gain/offset application, histogram modification techniques such as histogram equalization and manual histogram adjustment, and other more powerful techniques such as homomorphic filtering and 'burning and dodging'. The comparison is carried out by testing the suite of image enhancement methods on a set of diverse images. We find that though some of these techniques work well for some of these images, only the MSRCR performs universally well on the test set.

Enhancing multi-spot structured illumination microscopy with fluorescence difference

PubMed Central

Torkelsen, Frida H.

2018-01-01

Structured illumination microscopy is a super-resolution technique used extensively in biological research. However, this technique is limited in the maximum possible resolution increase. Here we report the results of simulations of a novel enhanced multi-spot structured illumination technique. This method combines the super-resolution technique of difference microscopy with structured illumination deconvolution. Initial results give at minimum a 1.4-fold increase in resolution over conventional structured illumination in a low-noise environment. This new technique also has the potential to be expanded to further enhance axial resolution with three-dimensional difference microscopy. The requirement for precise pattern determination in this technique also led to the development of a new pattern estimation algorithm which proved more efficient and reliable than other methods tested. PMID:29657751

Penile Enhancement Procedures with Simultaneous Penile Prosthesis Placement

PubMed Central

Hakky, Tariq S.; Suber, Jessica; Henry, Gerard; Smith, David; Bradley, Paul; Martinez, Daniel; Carrion, Rafael E.

2012-01-01

Here we present an overview of various techniques performed concomitantly during penile prosthesis surgery to enhance penile length and girth. We report on the technique of ventral phalloplasty and its outcomes along with augmentation corporoplasty, suprapubic lipectomy, suspensory ligament release, and girth enhancement procedures. For the serious implanter, outcomes can be improved by combining the use of techniques for each scar incision. These adjuvant procedures are a key addition in the armamentarium for the serious implant surgeon. PMID:22811703

Digital image enhancement techniques used in some ERTS application problems. [geology, geomorphology, and oceanography

NASA Technical Reports Server (NTRS)

Goetz, A. F. H.; Billingsley, F. C.

1974-01-01

Enhancements discussed include contrast stretching, multiratio color displays, Fourier plane operations to remove striping and boosting MTF response to enhance high spatial frequency content. The use of each technique in a specific application in the fields of geology, geomorphology and oceanography is demonstrated.

Classroom Techniques for Black Male Student Retention.

ERIC Educational Resources Information Center

Gardenhire, John Fouts

This paper describes and encourages the application of 20 classroom techniques to enhance the retention and success of black male college students. Though retention enhancement programs work best when institution-wide support and commitment are behind them, the techniques described here can be implemented in the classroom with significant results…

An automatic optimum kernel-size selection technique for edge enhancement

USGS Publications Warehouse

Chavez, Pat S.; Bauer, Brian P.

1982-01-01

Edge enhancement is a technique that can be considered, to a first order, a correction for the modulation transfer function of an imaging system. Digital imaging systems sample a continuous function at discrete intervals so that high-frequency information cannot be recorded at the same precision as lower frequency data. Because of this, fine detail or edge information in digital images is lost. Spatial filtering techniques can be used to enhance the fine detail information that does exist in the digital image, but the filter size is dependent on the type of area being processed. A technique has been developed by the authors that uses the horizontal first difference to automatically select the optimum kernel-size that should be used to enhance the edges that are contained in the image. 

Improved aortic enhancement in CT angiography using slope-based triggering with table speed optimization: a pilot study.

PubMed

Bashir, Mustafa R; Weber, Paul W; Husarik, Daniela B; Howle, Laurens E; Nelson, Rendon C

2012-08-01

To assess whether a scan triggering technique based on the slope of the time-attenuation curve combined with table speed optimization may improve arterial enhancement in aortic CT angiography compared to conventional threshold-based triggering techniques. Measurements of arterial enhancement were performed in a physiologic flow phantom over a range of simulated cardiac outputs (2.2-8.1 L/min) using contrast media boluses of 80 and 150 mL injected at 4 mL/s. These measurements were used to construct computer models of aortic attenuation in CT angiography, using cardiac output, aortic diameter, and CT table speed as input parameters. In-plane enhancement was calculated for normal and aneurysmal aortic diameters. Calculated arterial enhancement was poor (<150 HU) along most of the scan length using the threshold-based triggering technique for low cardiac outputs and the aneurysmal aorta model. Implementation of the slope-based triggering technique with table speed optimization improved enhancement in all scenarios and yielded good- (>200 HU; 13/16 scenarios) to excellent-quality (>300 HU; 3/16 scenarios) enhancement in all cases. Slope-based triggering with table speed optimization may improve the technical quality of aortic CT angiography over conventional threshold-based techniques, and may reduce technical failures related to low cardiac output and slow flow through an aneurysmal aorta.

Digital enhancement of computerized axial tomograms

NASA Technical Reports Server (NTRS)

Roberts, E., Jr.

1978-01-01

A systematic evaluation was conducted of certain digital image enhancement techniques performed in image space. Three types of images were used, computer generated phantoms, tomograms of a synthetic phantom, and axial tomograms of human anatomy containing images of lesions, artificially introduced into the tomograms. Several types of smoothing, sharpening, and histogram modification were explored. It was concluded that the most useful enhancement techniques are a selective smoothing of singular picture elements, combined with contrast manipulation. The most useful tool in applying these techniques is the gray-scale histogram.

Contrast-enhanced ultrasound in diagnosis and characterization of focal hepatic lesions.

PubMed

Molins, Inés Gómez; Font, Juan Manuel Fernández; Alvaro, Juan Carrero; Navarro, Jose Luís Lledó; Gil, Marta Fernández; Rodríguez, Conrado M Fernández

2010-12-28

The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases, has led to an important increase in identification of focal liver lesions. The development of contrast-enhanced ultrasound (CEUS) opens a new window in the diagnosis and follow-up of these lesions. This technique offers obvious advantages over the computed tomography and magnetic resonance, without a decrease in its sensitivity and specificity. The new second generation contrast agents, due to their intravascular distribution, allow a continuous evaluation of the enhancement pattern, which is crucial in characterization of liver lesions. The dual blood supply in the liver shows three different phases, namely arterial, portal and late phases. The enhancement during portal and late phases can give important information about the lesion's behavior. Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis. The role of emerging techniques as a contrast-enhanced three-dimensional US is also discussed. In this article, the advantages, indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed.

Contrast-enhanced ultrasound in diagnosis and characterization of focal hepatic lesions

PubMed Central

Molins, Inés Gómez; Font, Juan Manuel Fernández; Álvaro, Juan Carrero; Navarro, Jose Luís Lledó; Gil, Marta Fernández; Rodríguez, Conrado M Fernández

2010-01-01

The extensive use of imaging techniques in differential diagnosis of abdominal conditions and screening of hepatocellular carcinoma in patients with chronic hepatic diseases, has led to an important increase in identification of focal liver lesions. The development of contrast-enhanced ultrasound (CEUS) opens a new window in the diagnosis and follow-up of these lesions. This technique offers obvious advantages over the computed tomography and magnetic resonance, without a decrease in its sensitivity and specificity. The new second generation contrast agents, due to their intravascular distribution, allow a continuous evaluation of the enhancement pattern, which is crucial in characterization of liver lesions. The dual blood supply in the liver shows three different phases, namely arterial, portal and late phases. The enhancement during portal and late phases can give important information about the lesion’s behavior. Each liver lesion has a different enhancement pattern that makes possible an accurate approach to their diagnosis. The role of emerging techniques as a contrast-enhanced three-dimensional US is also discussed. In this article, the advantages, indications and technique employed during CEUS and the different enhancement patterns of most benign and malignant focal liver lesions are discussed. PMID:21225000

An Adaptive Image Enhancement Technique by Combining Cuckoo Search and Particle Swarm Optimization Algorithm

PubMed Central

Ye, Zhiwei; Wang, Mingwei; Hu, Zhengbing; Liu, Wei

2015-01-01

Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO) for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper. PMID:25784928

An adaptive image enhancement technique by combining cuckoo search and particle swarm optimization algorithm.

PubMed

Ye, Zhiwei; Wang, Mingwei; Hu, Zhengbing; Liu, Wei

2015-01-01

Image enhancement is an important procedure of image processing and analysis. This paper presents a new technique using a modified measure and blending of cuckoo search and particle swarm optimization (CS-PSO) for low contrast images to enhance image adaptively. In this way, contrast enhancement is obtained by global transformation of the input intensities; it employs incomplete Beta function as the transformation function and a novel criterion for measuring image quality considering three factors which are threshold, entropy value, and gray-level probability density of the image. The enhancement process is a nonlinear optimization problem with several constraints. CS-PSO is utilized to maximize the objective fitness criterion in order to enhance the contrast and detail in an image by adapting the parameters of a novel extension to a local enhancement technique. The performance of the proposed method has been compared with other existing techniques such as linear contrast stretching, histogram equalization, and evolutionary computing based image enhancement methods like backtracking search algorithm, differential search algorithm, genetic algorithm, and particle swarm optimization in terms of processing time and image quality. Experimental results demonstrate that the proposed method is robust and adaptive and exhibits the better performance than other methods involved in the paper.

Seed enhancement/upgrading techniques: Read the seed

Treesearch

Kim R. Creasy

2002-01-01

To the nursery industry in Canada, seed enhancing and upgrading techniques have ever increasingly become and are now an integral part of their operations prior to greenhouse sowing. The terms "enhancing" and "upgrading" can be used interchangeably, but they essentially mean the same thing. It's the idea of improving the quality of initial...

Holographic Radar Imaging Privacy Techniques Utilizing Dual-Frequency Implementation

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

McMakin, Douglas L.; Hall, Thomas E.; Sheen, David M.

2008-04-18

Over the last 15 years, the Pacific Northwest National Laboratory has performed significant research and development activities to enhance the state of the art of holographic radar imaging systems to be used at security checkpoints for screening people for concealed threats hidden under their garments. These enhancement activities included improvements to privacy techniques to remove human features and providing automatic detection of body-worn concealed threats. The enhanced privacy and detection methods used both physical and software imaging techniques. The physical imaging techniques included polarization-diversity illumination and reception, dual-frequency implementation, and high-frequency imaging at 60 GHz. Software imaging techniques to enhancemore » the privacy of the person under surveillance included extracting concealed threat artifacts from the imagery to automatically detect the threat. This paper will focus on physical privacy techniques using dual-frequency implementation.« less

Digital enhancement of sub-quality bitemark photographs.

PubMed

Karazalus, C P; Palmbach, T T; Lee, H C

2001-07-01

Digital enhancement software was used to enhance bitemark photographs. This enhancement technique improved the resolution of the bitemark images. Lucis was the software program utilized in this study and case applications. First, this technique was applied on known bitemark images to evaluate the potential effectiveness of this digital enhancement method. Subsequently, Lucis was utilized on two separate unsolved cases involving enhancement of bitemark evidence. One case involved a severely beaten infant with a bitemark on the upper thigh. The second case involves a bitemark observed on the breast of a female sexual assault strangulation victim. In both cases, bitemark images were significantly improved after digital enhancement.

The M&M Approach: Using Mental and Mechanical Strategies in Teaching and Coaching

ERIC Educational Resources Information Center

Rhea, Chris K.; Wisdom, Stacey

2007-01-01

Mental and mechanical (M&M) techniques are very useful in teaching and coaching. Mental techniques are strategies that enhance movement through psychological preparation, such as using imagery to practice a skill. Mechanical techniques are strategies that enhance the physical side of the movement, such as correcting the biomechanics of a golf…

Digital enhancement of computerized axial tomograms

NASA Technical Reports Server (NTRS)

Roberts, E., Jr.

1978-01-01

A systematic evaluation has been conducted of certain digital image enhancement techniques performed in image space. Three types of images have been used, computer generated phantoms, tomograms of a synthetic phantom, and axial tomograms of human anatomy containing images of lesions, artificially introduced into the tomograms. Several types of smoothing, sharpening, and histogram modification have been explored. It has been concluded that the most useful enhancement techniques are a selective smoothing of singular picture elements, combined with contrast manipulation. The most useful tool in applying these techniques is the gray-scale histogram.

Focused ultrasound-enhanced intranasal brain delivery of brain-derived neurotrophic factor

NASA Astrophysics Data System (ADS)

Chen, Hong; Yang, Georgiana Zong Xin; Getachew, Hoheteberhan; Acosta, Camilo; Sierra Sánchez, Carlos; Konofagou, Elisa E.

2016-06-01

The objective of this study was to unveil the potential mechanism of focused ultrasound (FUS)-enhanced intranasal (IN) brain drug delivery and assess its feasibility in the delivery of therapeutic molecules. Delivery outcomes of fluorescently-labeled dextrans to mouse brains by IN administration either before or after FUS sonication were compared to evaluate whether FUS enhances IN delivery by active pumping or passive diffusion. Fluorescence imaging of brain slices found that IN administration followed by FUS sonication achieved significantly higher delivery than IN administration only, while pre-treatment by FUS sonication followed by IN administration was not significantly different from IN administration only. Brain-derived neurotrophic factor (BDNF), a promising neurotrophic factor for the treatment of many central nervous system diseases, was delivered by IN followed by FUS to demonstrate the feasibility of this technique and compared with the established FUS technique where drugs are injected intravenously. Immunohistochemistry staining of BDNF revealed that FUS-enhanced IN delivery achieved similar locally enhanced delivery as the established FUS technique. This study suggested that FUS enhances IN brain drug delivery by FUS-induced active pumping of the drug and demonstrated that FUS-enhanced IN delivery is a promising technique for noninvasive and localized delivery of therapeutic molecules to the brain.

Local gray level S-curve transformation - A generalized contrast enhancement technique for medical images.

PubMed

Gandhamal, Akash; Talbar, Sanjay; Gajre, Suhas; Hani, Ahmad Fadzil M; Kumar, Dileep

2017-04-01

Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bond enhancement techniques for PCC white topping

DOT National Transportation Integrated Search

1996-01-01

This research was initiated in 1991 as a part of a whitetopping project to study the effectiveness of various techniques to enhance bond strength between a new portland cement concrete (PCC) overlay and an existing asphalt cement concrete (ACC) pavem...

Male chest enhancement: pectoral implants.

PubMed

Benito-Ruiz, J; Raigosa, J M; Manzano-Surroca, M; Salvador, L

2008-01-01

The authors present their experience with the pectoral muscle implant for male chest enhancement in 21 patients. The markings and technique are thoroughly described. The implants used were manufactured and custom made. The candidates for implants comprised three groups: group 1 (18 patients seeking chest enhancement), group 2 (1 patient with muscular atrophy), and group 3 (2 patients with muscular injuries). Because of the satisfying results obtained, including significant enhancement of the chest contour and no major complications, this technique is used for an increasing number of male cosmetic surgeries.

Large surface-enhanced Raman scattering from self-assembled gold nanosphere monolayers

NASA Astrophysics Data System (ADS)

Fontana, Jake; Livenere, John; Bezares, Francisco J.; Caldwell, Joshua D.; Rendell, Ronald; Ratna, Banahalli R.

2013-05-01

We demonstrate an average surface-enhanced Raman scattering enhancement on the order of 108 from benzenethiol molecules using self-assembled, macroscopic, and tunable gold nanosphere monolayers on non-templated substrates. The self-assembly of the nanosphere monolayers uses a simple and efficient technique that allows for the creation of a high-density, chemically functionalized gold nanosphere monolayers with enhancement factors comparable to those produced using top-down fabrication techniques. These films may provide an approach for the future development of portable chemical/biological sensors.

Balance Contrast Enhancement using piecewise linear stretching

NASA Astrophysics Data System (ADS)

Rahavan, R. V.; Govil, R. C.

1993-04-01

Balance Contrast Enhancement is one of the techniques employed to produce color composites with increased color contrast. It equalizes the three images used for color composition in range and mean. This results in a color composite with large variation in hue. Here, it is shown that piecewise linear stretching can be used for performing the Balance Contrast Enhancement. In comparison with the Balance Contrast Enhancement Technique using parabolic segment as transfer function (BCETP), the method presented here is algorithmically simple, constraint-free and produces comparable results.

Evaluation of pulmonary function using single-breath-hold dual-energy computed tomography with xenon

PubMed Central

Kyoyama, Hiroyuki; Hirata, Yusuke; Kikuchi, Satoshi; Sakai, Kosuke; Saito, Yuriko; Mikami, Shintaro; Moriyama, Gaku; Yanagita, Hisami; Watanabe, Wataru; Otani, Katharina; Honda, Norinari; Uematsu, Kazutsugu

2017-01-01

Abstract Xenon-enhanced dual-energy computed tomography (xenon-enhanced CT) can provide lung ventilation maps that may be useful for assessing structural and functional abnormalities of the lung. Xenon-enhanced CT has been performed using a multiple-breath-hold technique during xenon washout. We recently developed xenon-enhanced CT using a single-breath-hold technique to assess ventilation. We sought to evaluate whether xenon-enhanced CT using a single-breath-hold technique correlates with pulmonary function testing (PFT) results. Twenty-six patients, including 11 chronic obstructive pulmonary disease (COPD) patients, underwent xenon-enhanced CT and PFT. Three of the COPD patients underwent xenon-enhanced CT before and after bronchodilator treatment. Images from xenon-CT were obtained by dual-source CT during a breath-hold after a single vital-capacity inspiration of a xenon–oxygen gas mixture. Image postprocessing by 3-material decomposition generated conventional CT and xenon-enhanced images. Low-attenuation areas on xenon images matched low-attenuation areas on conventional CT in 21 cases but matched normal-attenuation areas in 5 cases. Volumes of Hounsfield unit (HU) histograms of xenon images correlated moderately and highly with vital capacity (VC) and total lung capacity (TLC), respectively (r = 0.68 and 0.85). Means and modes of histograms weakly correlated with VC (r = 0.39 and 0.38), moderately with forced expiratory volume in 1 second (FEV1) (r = 0.59 and 0.56), weakly with the ratio of FEV1 to FVC (r = 0.46 and 0.42), and moderately with the ratio of FEV1 to its predicted value (r = 0.64 and 0.60). Mode and volume of histograms increased in 2 COPD patients after the improvement of FEV1 with bronchodilators. Inhalation of xenon gas caused no adverse effects. Xenon-enhanced CT using a single-breath-hold technique depicted functional abnormalities not detectable on thin-slice CT. Mode, mean, and volume of HU histograms of xenon images reflected pulmonary function. Xenon images obtained with xenon-enhanced CT using a single-breath-hold technique can qualitatively depict pulmonary ventilation. A larger study comprising only COPD patients should be conducted, as xenon-enhanced CT is expected to be a promising technique for the management of COPD. PMID:28099359

Evaluation of pulmonary function using single-breath-hold dual-energy computed tomography with xenon: Results of a preliminary study.

PubMed

Kyoyama, Hiroyuki; Hirata, Yusuke; Kikuchi, Satoshi; Sakai, Kosuke; Saito, Yuriko; Mikami, Shintaro; Moriyama, Gaku; Yanagita, Hisami; Watanabe, Wataru; Otani, Katharina; Honda, Norinari; Uematsu, Kazutsugu

2017-01-01

Xenon-enhanced dual-energy computed tomography (xenon-enhanced CT) can provide lung ventilation maps that may be useful for assessing structural and functional abnormalities of the lung. Xenon-enhanced CT has been performed using a multiple-breath-hold technique during xenon washout. We recently developed xenon-enhanced CT using a single-breath-hold technique to assess ventilation. We sought to evaluate whether xenon-enhanced CT using a single-breath-hold technique correlates with pulmonary function testing (PFT) results.Twenty-six patients, including 11 chronic obstructive pulmonary disease (COPD) patients, underwent xenon-enhanced CT and PFT. Three of the COPD patients underwent xenon-enhanced CT before and after bronchodilator treatment. Images from xenon-CT were obtained by dual-source CT during a breath-hold after a single vital-capacity inspiration of a xenon-oxygen gas mixture. Image postprocessing by 3-material decomposition generated conventional CT and xenon-enhanced images.Low-attenuation areas on xenon images matched low-attenuation areas on conventional CT in 21 cases but matched normal-attenuation areas in 5 cases. Volumes of Hounsfield unit (HU) histograms of xenon images correlated moderately and highly with vital capacity (VC) and total lung capacity (TLC), respectively (r = 0.68 and 0.85). Means and modes of histograms weakly correlated with VC (r = 0.39 and 0.38), moderately with forced expiratory volume in 1 second (FEV1) (r = 0.59 and 0.56), weakly with the ratio of FEV1 to FVC (r = 0.46 and 0.42), and moderately with the ratio of FEV1 to its predicted value (r = 0.64 and 0.60). Mode and volume of histograms increased in 2 COPD patients after the improvement of FEV1 with bronchodilators. Inhalation of xenon gas caused no adverse effects.Xenon-enhanced CT using a single-breath-hold technique depicted functional abnormalities not detectable on thin-slice CT. Mode, mean, and volume of HU histograms of xenon images reflected pulmonary function. Xenon images obtained with xenon-enhanced CT using a single-breath-hold technique can qualitatively depict pulmonary ventilation. A larger study comprising only COPD patients should be conducted, as xenon-enhanced CT is expected to be a promising technique for the management of COPD.

Hepatic lesions: improved image quality and detection with the periodically rotated overlapping parallel lines with enhanced reconstruction technique--evaluation of SPIO-enhanced T2-weighted MR images.

PubMed

Hirokawa, Yuusuke; Isoda, Hiroyoshi; Maetani, Yoji S; Arizono, Shigeki; Shimada, Kotaro; Okada, Tomohisa; Shibata, Toshiya; Togashi, Kaori

2009-05-01

To evaluate the effectiveness of the periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) technique for superparamagnetic iron oxide (SPIO)-enhanced T2-weighted magnetic resonance (MR) imaging with respiratory compensation with the prospective acquisition correction (PACE) technique in the detection of hepatic lesions. The institutional human research committee approved this prospective study, and all patients provided written informed consent. Eighty-one patients (mean age, 58 years) underwent hepatic 1.5-T MR imaging. Fat-saturated T2-weighted turbo spin-echo images were acquired with the PACE technique and with and without the PROPELLER method after administration of SPIO. Images were qualitatively evaluated for image artifacts, depiction of liver edge and intrahepatic vessels, overall image quality, and presence of lesions. Three radiologists independently assessed these characteristics with a five-point confidence scale. Diagnostic performance was assessed with receiver operating characteristic (ROC) curve analysis. Quantitative analysis was conducted by measuring the liver signal-to-noise ratio (SNR) and the lesion-to-liver contrast-to-noise ratio (CNR). The Wilcoxon signed rank test and two-tailed Student t test were used, and P < .05 indicated a significant difference. MR imaging with the PROPELLER and PACE techniques resulted in significantly improved image quality, higher sensitivity, and greater area under the ROC curve for hepatic lesion detection than did MR imaging with the PACE technique alone (P < .001). The mean liver SNR and the lesion-to-liver CNR were higher with the PROPELLER technique than without it (P < .001). T2-weighted MR imaging with the PROPELLER and PACE technique and SPIO enhancement is a promising method with which to improve the detection of hepatic lesions. (c) RSNA, 2009.

Flow-based analysis using microfluidics-chemiluminescence systems.

PubMed

Al Lawati, Haider A J

2013-01-01

This review will discuss various approaches and techniques in which analysis using microfluidics-chemiluminescence systems (MF-CL) has been reported. A variety of applications is examined, including environmental, pharmaceutical, biological, food and herbal analysis. Reported uses of CL reagents, sample introduction techniques, sample pretreatment methods, CL signal enhancement and detection systems are discussed. A hydrodynamic pumping system is predominately used for these applications. However, several reports are available in which electro-osmotic (EO) pumping has been implemented. Various sample pretreatment methods have been used, including liquid-liquid extraction, solid-phase extraction and molecularly imprinted polymers. A wide range of innovative techniques has been reported for CL signal enhancement. Most of these techniques are based on enhancement of the mixing process in the microfluidics channels, which leads to enhancement of the CL signal. However, other techniques are also reported, such as mirror reaction, liquid core waveguide, on-line pre-derivatization and the use of an opaque white chip with a thin transparent seal. Photodetectors are the most commonly used detectors; however, other detection systems have also been used, including integrated electrochemiluminescence (ECL) and organic photodiodes (OPDs). Copyright © 2012 John Wiley & Sons, Ltd.

Simulation of pattern and defect detection in periodic amplitude and phase structures using photorefractive four-wave mixing

NASA Astrophysics Data System (ADS)

Nehmetallah, Georges; Banerjee, Partha; Khoury, Jed

2015-03-01

The nonlinearity inherent in four-wave mixing in photorefractive (PR) materials is used for adaptive filtering. Examples include script enhancement on a periodic pattern, scratch and defect cluster enhancement, periodic pattern dislocation enhancement, etc. through intensity filtering image manipulation. Organic PR materials have large space-bandwidth product, which makes them useful in adaptive filtering techniques in quality control systems. For instance, in the case of edge enhancement, phase conjugation via four-wave mixing suppresses the low spatial frequencies of the Fourier spectrum of an aperiodic image and consequently leads to image edge enhancement. In this work, we model, numerically verify, and simulate the performance of a four wave mixing setup used for edge, defect and pattern detection in periodic amplitude and phase structures. The results show that this technique successfully detects the slightest defects clearly even with no enhancement. This technique should facilitate improvements in applications such as image display sharpness utilizing edge enhancement, production line defect inspection of fabrics, textiles, e-beam lithography masks, surface inspection, and materials characterization.

Ultrafast and nonlinear surface-enhanced Raman spectroscopy.

PubMed

Gruenke, Natalie L; Cardinal, M Fernanda; McAnally, Michael O; Frontiera, Renee R; Schatz, George C; Van Duyne, Richard P

2016-04-21

Ultrafast surface-enhanced Raman spectroscopy (SERS) has the potential to study molecular dynamics near plasmonic surfaces to better understand plasmon-mediated chemical reactions such as plasmonically-enhanced photocatalytic or photovoltaic processes. This review discusses the combination of ultrafast Raman spectroscopic techniques with plasmonic substrates for high temporal resolution, high sensitivity, and high spatial resolution vibrational spectroscopy. First, we introduce background information relevant to ultrafast SERS: the mechanisms of surface enhancement in Raman scattering, the characterization of plasmonic materials with ultrafast techniques, and early complementary techniques to study molecule-plasmon interactions. We then discuss recent advances in surface-enhanced Raman spectroscopies with ultrafast pulses with a focus on the study of molecule-plasmon coupling and molecular dynamics with high sensitivity. We also highlight the challenges faced by this field by the potential damage caused by concentrated, highly energetic pulsed fields in plasmonic hotspots, and finally the potential for future ultrafast SERS studies.

The O-Buoy Chemical Network

NASA Astrophysics Data System (ADS)

Matrai, P. A.; Williams, C. R.; Rauschenberg, C. D.

2012-12-01

Autonomous, sea ice-tethered buoys ("O-Buoys") are being deployed across the Arctic sea ice for long-term atmospheric measurements, with several O-Buoys having been deployed within the Hudson Bay, Beaufort Sea, and the North Pole. These buoys provide in-situ measurements of ozone, CO_{2} and BrO, as well as meteorological parameters, over the frozen ocean. O-Buoys were designed to transmit daily data over a period of 2 years while deployed in sea ice, as part of automated ice-drifting stations. Due to the logistical challenges of measurements over the Arctic Ocean region, most long term,in-situ observations of atmospheric chemistry have been made at coastal sites or islands near the coast, leaving large spatial and temporal gaps that O-Buoys can overcome. The significant uncertainty that remains in our understanding of the temporal and spatial variability in these parameters as well as the magnitude and/or frequency of long (CO_{2}) and short (ozone depletion) patterns can be overcome. Advances in floatation, communications, power management, and sensor hardware have been made to the original design to overcome the challenges of diminished Arctic sea ice which have resulted in our longest deployments into the summer so far.

Polishing Step Purification of High-Strength Wastewaters by Nanofiltration and Reverse Osmosis

PubMed Central

Zhou, Jinxiang; Baker, Brian O.; Grimsley, Charles T.; Husson, Scott M.

2016-01-01

This article reports findings on the use of nanofiltration (NF) and reverse osmosis (RO) for secondary treatment of high-strength rendering facility wastewaters following an ultrafiltration step. These wastewaters present significant challenges to classical treatment technologies. Constant-pressure, direct-flow membrane filtration experiments were done to screen for flux and effluent water permeate quality of ten commercial NF and RO membranes. All membranes tested were effective in reducing total dissolved salts (TDS) and chemical oxygen demand (COD); however, only two membranes (Koch MPF-34 and Toray 70UB) gave sufficiently stable flux values to warrant longer term cross-flow filtration studies. Cross-flow flux measurements, scanning electron microscopy (SEM), X-ray dispersive spectroscopy (EDS), and attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR) indicated that both membranes were eventually fouled by organic and inorganic foulants; however, the Toray 70UB RO membrane yielded a capacity of 1600 L/m2 prior to cleaning. A preliminary economic analysis compared the estimated costs of energy and consumables for a dual-stage UF/RO membrane process and dissolved air floatation (DAF) and found membrane process costs could be less than about 40% of the current DAF process. PMID:26978407

Pilot test of pollution control and metal resource recovery for acid mine drainage.

PubMed

Yan, Bo; Mai, Ge; Chen, Tao; Lei, Chang; Xiao, Xianming

2015-01-01

The study was undertaken in order to recover the metal resources from acid mine drainage (AMD). A 300 m(3)/d continuous system was designed and fractional precipitation technology employed for the main metals Fe, Cu, Zn, and Mn recovery. The system was operated for six months using actual AMD in situ. The chemicals' input and also the retention time was optimized. Furthermore, the material balance was investigated. With the system, the heavy metals of the effluent after the Mn neutralization precipitation were below the threshold value of the Chinese integrated wastewater discharge limit. The precipitates generated contained 42%, 12%, 31%, and 18% for Fe, Cu, Zn, and Mn, respectively, and the recovery rates of Fe, Cu, Zn, and Mn were 82%, 79%, 83%, and 83%, respectively. The yield range of the precipitate had significant correlation with the influent metal content. Using the X-ray diffraction analysis, the refinement for Fe, Cu, and Zn could be achieved through the processes of roasting and floatation. Cost-benefit was also discussed; the benefit from the recycled metal was able to pay for the cost of chemical reagents used. Most important of all, through the use of this technology, the frustrating sludge problems were solved.

Expansion rate and geometry of floating vegetation mats on the margins of thermokarst lakes, northern Seward Peninsula, Alaska, USA

USGS Publications Warehouse

Parsekian, A.D.; Jones, Benjamin M.; Jones, M.; Grosse, G.; Walter, Anthony K.M.; Slater, L.

2011-01-01

Investigations on the northern Seward Peninsula in Alaska identified zones of recent (<50years) permafrost collapse that led to the formation of floating vegetation mats along thermokarst lake margins. The occurrence of floating vegetation mat features indicates rapid degradation of near-surface permafrost and lake expansion. This paper reports on the recent expansion of these collapse features and their geometry is determined using geophysical and remote sensing measurements. The vegetation mats were observed to have an average thickness of 0.57m and petrophysical modeling indicated that gas content of 1.5-5% enabled floatation above the lake surface. Furthermore, geophysical investigation provides evidence that the mats form by thaw and subsidence of the underlying permafrost rather than terrestrialization. The temperature of the water below a vegetation mat was observed to remain above freezing late in the winter. Analysis of satellite and aerial imagery indicates that these features have expanded at maximum rates of 1-2myr-1 over a 56year period. Including the spatial coverage of floating 'thermokarst mats' increases estimates of lake area by as much as 4% in some lakes. ?? 2011 John Wiley & Sons, Ltd.

Apparatus for restraining and transporting dies

DOEpatents

Allison, James W.; LaBarre, Timothy L.

1994-01-01

Apparatus for restraining and transporting dies in punch press operations is provided. A floatation platen for supporting a die on the platen's upper surface has a plurality of recessed gas exhaust ports on the platen's lower surface. A source of pressurized gas delivers gas to a platen manifold, for delivery to orifices located in the gas exhaust ports. The flow of gas is controlled by a first valve adjacent the gas source and a second valve adjacent the manifold, with the second valve being used to control the gas flow during movement of the die. In this fashion, a die may be moved on a cushion of air from one workstation to a selected second workstation. A moveable hydraulically operated restraining fixture is also provided, for clamping the die in position during the compacting phase, and for releasing the die after completion of the compacting phase by releasing the hydraulic pressure on the restraining fixture. When pressure in the hydraulic cylinders on the restraining fixture is reversed, the restraining fixture will retract so that there is no contact between the die and the restraining fixture, thereby allowing the die to be removed from a first workstation and moved to a second selected workstation.

Grain Floatation During Equiaxed Solidification of an Al-Cu Alloy in a Side-Cooled Cavity: Part II—Numerical Studies

NASA Astrophysics Data System (ADS)

Kumar, Arvind; Walker, Mike J.; Sundarraj, Suresh; Dutta, Pradip

2011-08-01

In this article, a single-phase, one-domain macroscopic model is developed for studying binary alloy solidification with moving equiaxed solid phase, along with the associated transport phenomena. In this model, issues such as thermosolutal convection, motion of solid phase relative to liquid and viscosity variations of the solid-liquid mixture with solid fraction in the mobile zone are taken into account. Using the model, the associated transport phenomena during solidification of Al-Cu alloys in a rectangular cavity are predicted. The results for temperature variation, segregation patterns, and eutectic fraction distribution are compared with data from in-house experiments. The model predictions compare well with the experimental results. To highlight the influence of solid phase movement on convection and final macrosegregation, the results of the current model are also compared with those obtained from the conventional solidification model with stationary solid phase. By including the independent movement of the solid phase into the fluid transport model, better predictions of macrosegregation, microstructure, and even shrinkage locations were obtained. Mechanical property prediction models based on microstructure will benefit from the improved accuracy of this model.

Simple explant culture of the embryonic chicken retina with long-term preservation of photoreceptors.

PubMed

Thangaraj, Gopenath; Greif, Alexander; Layer, Paul G

2011-10-01

Structurally stable in vitro-model systems are indispensible to analyse neural development during embryogenesis, follow cellular differentiation and evaluate neurotoxicological or growth factor effects. Here we describe a three-dimensional, long-term in vitro-culture system of the embryonic chick retina which supports photoreceptor development. Retinal tissue was isolated from E6 chick eye, and cultured as explants by continuous orbital rotation to allow free floatation without any supporting materials. Young stage (E6) immature retinas were cultured for various time periods in order to follow the differentiation of cell types and plexiform layers by immunocytochemical methods. These explants could be cultured for at least 2-3 weeks with remarkable retention of retinal architecture. Interestingly, photoreceptors developed in the absence of pigment epithelium. Electron microscopic studies revealed formation of structures resembling photoreceptor outer segments, a feature not reported previously. Thus, the verification of photoreceptors, Müller cells, inner retinal cells and the inner plexiform layer described in our study establishes this explant culture as a valuable in vivo-like model system. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Molecular identification of parasitic nematodes (Nematoda: Strongylida) in feces of wild ruminants from Tunisia.

PubMed

Said, Yousra; Gharbi, Mohamed; Mhadhbi, Moez; Dhibi, Moktar; Lahmar, Samia

2017-11-08

In Tunisia and other North African countries, there is a lack of knowledge about parasite biodiversity within threatened wild ruminants and there are not any studies on their gastrointestinal nematodes. Thus the aim of this study was to identify gastrointestinal fauna in the faecal samples of Tunisian wild ruminants. A total of 262 faecal samples were collected from domestic sheep and goat, and wild ruminants (Addax, Barbary sheep, Barbary red deer, Dorcas gazelle, Slender-horned gazelle and Scimitar-horned Oryx) living in protected areas. Samples were examined with floatation (saturated sodium chloride solution), polymerase chain reaction and sequencing of the second internal transcribed spacer region of the rDNA. Microscopic analysis allowed the identification of only Nematodirus genus or molecular tools allowed a first identification of five gastrointestinal nematode species in North African wild ruminants: Chabertia ovina (1.6%), Camelostrongylus mentulatus (1.6%), Marshallagia marshalli (4.7%), Nematodirus helvetianus (62.5%) and Nematodirus spathiger (29.7%). This study reported the first records of C. mentulatus and M. marshalli in Addax and of M. marshalli in Dorcas gazelle and it was the first reported record of N. helvetianus and M. marshalli in Tunisia.

Survey on gastrointestinal parasites and detection of Cryptosporidium spp. on cattle in West Java, Indonesia.

PubMed

Ananta, Sylvia Maharani; Suharno; Hidayat, Adi; Matsubayashi, Makoto

2014-03-01

To evaluate the presence of gastrointestinal parasites on cattle in Indonesia because the prevalence of parasites varies between countries depending on the terrain surrounding livestock farms and investigations in Indonesia have never been performed. Fecal samples from cattle at 35 farms in 7 districts in West Java, Indonesia, has been examined using the floatation or sedimentation methods, and a immunofluorescence assay and experimentally inoculation to mice for Cryptosporidium or Giardia.spp. 153 of 394 examined cattle (38.8%) were infected with gastrointestinal parasites. The prevalence of Eimeria spp., Nematoda spp. (including Oesophagustomum and Bunostomum-like), Fasciola gigantica and Paramphistomum spp. was 22.4%, 11.2%, 12.5% and 3.8%, respectively. Cryptosporidium andersoni (C. andersoni) was also found in two samples. One isolate of this parasite was confirmed to be transmitted to mice, in contrast to the isolates from other countries. although this survey is preliminary, the results shows that the infection of gastrointestinal parasites in Indonesia was not high, but these infected cattle could be as a potential source leading to economic losses in livestock production. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Gastrointestinal Helminths in Slaughtered Cattle in Ibadan, South-Western Nigeria.

PubMed

Adedipe, Olubukola Deborah; Uwalaka, Emmanuel Chibuike; Akinseye, Victor Oluwatoyin; Adediran, Oyeduntan Adejoju; Cadmus, Simeon Idowu Babalola

2014-01-01

As part of an ongoing project to investigate the epidemiology of gastrointestinal helminths of cattle in Nigeria, we carried out a systematic random sampling of cattle slaughtered in a major abattoir in Ibadan, south-western Nigeria. Using sedimentation and floatation methods, we analyzed fecal samples from 397 animals between March and May 2013. Overall, 163 (41.6%) of the animals had at least one gastrointestinal helminth egg, comprising a total of eight helminths from different genera (i.e., four nematodes, three trematodes, and one cestode), with nematode infection being the highest (71.54%). In addition, eggs of four helminths of zoonotic importance were also obtained. Among the cattle examined, the Bunaji breed was the most infected (46%; 69/150). Furthermore, female animals (OR = 1.1; 95% CI: 0.60-1.84) and animals with moderate body condition (OR = 1.2; 95% CI: 0.80-1.79) are more likely to be positive to helminth infection. Our findings reveal that there were helminth infections of both zoonotic and socioeconomic importance among the cattle screened. Considering the impact of the infections on animal production and public health, we advocate that effective prophylactic measures be adopted as a first step to curtail helminth infections of cattle in Nigeria.

Floating dosage forms to prolong gastro-retention--the characterisation of calcium alginate beads.

PubMed

Stops, Frances; Fell, John T; Collett, John H; Martini, Luigi G

2008-02-28

Floating calcium alginate beads, designed to improve drug bioavailability from oral preparations compared with that from many commercially available and modified release products, have been investigated as a possible gastro-retentive dosage form. A model drug, riboflavin, was also incorporated into the formula. The aims of the current work were (a) to obtain information regarding the structure, floating ability and changes that occurred when the dosage form was placed in aqueous media, (b) to investigate riboflavin release from the calcium alginate beads in physiologically relevant media prior to in vivo investigations. Physical properties of the calcium alginate beads were investigated. Using SEM and ESEM, externally the calcium alginate beads were spherical in shape, and internally, air filled cavities were present thereby enabling floatation of the beads. The calcium alginate beads remained buoyant for times in excess of 13h, and the density of the calcium alginate beads was <1.000gcm(-3). Riboflavin release from the calcium alginate beads showed that riboflavin release was slow in acidic media, whilst in more alkali media, riboflavin release was more rapid. The characterisation studies showed that the calcium alginate beads could be considered as a potential gastro-retentive dosage form.

Effect of matrix composition and process conditions on casein-gelatin beads floating properties.

PubMed

Bulgarelli, E; Forni, F; Bernabei, M T

2000-04-05

Casein-gelatin beads have been prepared by emulsification extraction method and cross-linked with D,L-glyceraldehyde in an acetone-water mixture 3:1 (v/v). Casein emulsifying properties cause air bubble incorporation and the formation of large holes in the beads. The high porosity of the matrix influences the bead properties such as drug loading, drug release and floatation. These effects have been stressed by comparison with low porous beads, artificially prepared without cavities. The percentage of casein in the matrix increases the drug loading of both low and high porous matrices, although the loading of high porous matrices is lower than that of low porous matrices. As a matter of fact, the drug should be more easily removed during washing and recovery because of the higher superficial pore area of the beads. This can explain the drug release rate increase, observed in high porous matrix, in comparison with beads without cavities. This is due to the rapid diffusion of the drug through water filled pores. The study shows that cavities act as an air reservoir and enable beads to float. Therefore, casein seems to be a material suitable to the inexpensive formation of an air reservoir for floating systems.

Assembled modules technology for site-specific prolonged delivery of norfloxacin.

PubMed

Oliveira, Paulo Renato; Bernardi, Larissa Sakis; Strusi, Orazio Luca; Mercuri, Salvatore; Segatto Silva, Marcos A; Colombo, Paolo; Sonvico, Fabio

2011-02-28

The aim of this research was to design and study norfloxacin (NFX) release in floating conditions from compressed hydrophilic matrices of hydroxypropylmethylcellulose (HPMC) or poly(ethylene oxide) (PEO). Module assembling technology for drug delivery system manufacturing was used. Two differently cylindrical base curved matrix/modules, identified as female and male, were assembled in void configuration by friction interlocking their concave bases obtaining a floating release system. Drug release and floatation behavior of this assembly was investigated. Due to the higher surface area exposed to the release medium, faster release was observed for individual modules compared to their assembled configuration, independently on the polymer used and concentration. The release curves analyzed using the Korsmeyer exponential equation and Peppas & Sahlin binomial equation showed that the drug release was controlled both by drug diffusion and polymer relaxation or erosion mechanisms. However, convective transport was predominant with PEO and at low content of polymers. NFX release from PEO polymeric matrix was more erosion dependent than HPMC. The assembled systems were able to float in vitro for up to 240min, indicating that this drug delivery system of norfloxacin could provide gastro-retentive site-specific release for increasing norfloxacin bioavailability. Copyright © 2010. Published by Elsevier B.V.

Formulation and evaluation of gastroretentive microballoons containing baclofen for a floating oral controlled drug delivery system.

PubMed

Dube, T S; Ranpise, N S; Ranade, A N

2014-01-01

The objective of the present study was to fabricate and evaluate a multiparticulate oral gastroretentive dosage form of baclofen characterized by a central large cavity (hollow core) promoting unmitigated floatation with practical applications to alleviate the signs and symptoms of spasticity and muscular rigidity. Solvent diffusion and evaporation procedure were applied to prepare floating microspheres with a central large cavity using various combinations of ethylcellulose (release retardant) and HPMC K4M (release modifier) dissolved in a mixture of dichloromethane and methanol (2:1). The obtained microspheres (700-1000 µm) exhibit excellent floating ability (86 ± 2.00%) and release characteristics with entrapment efficiency of 95.2 ± 0.32%. Microspheres fabricated with ethylcellulose to HPMC K4M in the ratio 8.5:1.5 released 98.67% of the entrapped drug in 12 h. Muscle relaxation caused by baclofen microspheres impairs the rotarod performance for more than 12 h. Abdominal X-ray images showed that the gastroretention period of the floating barium sulfate- labeled microspheres was no less than 10 h. The buoyant baclofen microspheres provide a promising gastroretentive drug delivery system to deliver baclofen in spastic patients with a sustained release rate.

Surface-enhanced FAST CARS: en route to quantum nano-biophotonics

NASA Astrophysics Data System (ADS)

Voronine, Dmitri V.; Zhang, Zhenrong; Sokolov, Alexei V.; Scully, Marlan O.

2018-02-01

Quantum nano-biophotonics as the science of nanoscale light-matter interactions in biological systems requires developing new spectroscopic tools for addressing the challenges of detecting and disentangling weak congested optical signals. Nanoscale bio-imaging addresses the challenge of the detection of weak resonant signals from a few target biomolecules in the presence of the nonresonant background from many undesired molecules. In addition, the imaging must be performed rapidly to capture the dynamics of biological processes in living cells and tissues. Label-free non-invasive spectroscopic techniques are required to minimize the external perturbation effects on biological systems. Various approaches were developed to satisfy these requirements by increasing the selectivity and sensitivity of biomolecular detection. Coherent anti-Stokes Raman scattering (CARS) and surface-enhanced Raman scattering (SERS) spectroscopies provide many orders of magnitude enhancement of chemically specific Raman signals. Femtosecond adaptive spectroscopic techniques for CARS (FAST CARS) were developed to suppress the nonresonant background and optimize the efficiency of the coherent optical signals. This perspective focuses on the application of these techniques to nanoscale bio-imaging, discussing their advantages and limitations as well as the promising opportunities and challenges of the combined coherence and surface enhancements in surface-enhanced coherent anti-Stokes Raman scattering (SECARS) and tip-enhanced coherent anti-Stokes Raman scattering (TECARS) and the corresponding surface-enhanced FAST CARS techniques. Laser pulse shaping of near-field excitations plays an important role in achieving these goals and increasing the signal enhancement.

General method to evaluate substrate surface modification techniques for light extraction enhancement of organic light emitting diodes

NASA Astrophysics Data System (ADS)

Krummacher, B. C.; Mathai, M. K.; Choong, V.; Choulis, S. A.; So, F.; Winnacker, A.

2006-09-01

The external light output of organic light emitting diodes (OLEDs) can be increased by modifying the light emitting surface. The apparent light extraction enhancement is given by the ratio between the efficiency of the unmodified device and the efficiency of the modified device. This apparent light extraction enhancement is dependent on the OLED architecture itself and is not the correct value to judge the effectiveness of a technique to enhance light outcoupling due to substrate surface modification. We propose a general method to evaluate substrate surface modification techniques for light extraction enhancement of OLEDs independent from the device architecture. This method is experimentally demonstrated using green electrophosphorescent OLEDs with different device architectures. The substrate surface of these OLEDs was modified by applying a prismatic film to increase light outcoupling from the device stack. It was demonstrated that the conventionally measured apparent light extraction enhancement by means of the prismatic film does not reflect the actual performance of the light outcoupling technique. Rather, by comparing the light extracted out of the prismatic film to that generated in the OLED layers and coupled into the substrate (before the substrate/air interface), a more accurate evaluation of light outcoupling enhancement can be achieved. Furthermore we show that substrate surface modification can change the output spectrum of a broad band emitting OLED.

Convective Heat Transfer Enhancement Using Alternating Magnetic Fields and Particle Laden Fluid Applied to the Microscale

DTIC Science & Technology

2010-05-11

convective heat transfer , researchers have been drawn to the high heat flux potentials of microfluidic devices. Microchannel flows, with hydraulic...novel heat transfer enhancement technique proven on the conventional scale to the mini and microchannel scales. 1.3 Background: Conventional...S.G., 2004, “Single-Phase Heat Transfer Enhancement Techniques in Microchannel and Minichannel Flows,” International Conference on Microchannels

Diazo processing of LANDSAT imagery: A low-cost instructional technique

NASA Technical Reports Server (NTRS)

Lusch, D. P.

1981-01-01

Diazo processing of LANDSAT imagery is a relatively simple and cost effective method of producing enhanced renditions of the visual LANDSAT products. This technique is capable of producing a variety of image enhancements which have value in a teaching laboratory environment. Additionally, with the appropriate equipment, applications research which relys on accurate and repeatable results is possible. Exposure and development equipment options, diazo materials, and enhancement routines are discussed.

Surface-Enhanced Raman Spectroscopy.

ERIC Educational Resources Information Center

Garrell, Robin L.

1989-01-01

Reviews the basis for the technique and its experimental requirements. Describes a few examples of the analytical problems to which surface-enhanced Raman spectroscopy (SERS) has been and can be applied. Provides a perspective on the current limitations and frontiers in developing SERS as an analytical technique. (MVL)

Visual enhancement of images of natural resources: Applications in geology

NASA Technical Reports Server (NTRS)

Dejesusparada, N. (Principal Investigator); Neto, G.; Araujo, E. O.; Mascarenhas, N. D. A.; Desouza, R. C. M.

1980-01-01

The principal components technique for use in multispectral scanner LANDSAT data processing results in optimum dimensionality reduction. A powerful tool for MSS IMAGE enhancement, the method provides a maximum impression of terrain ruggedness; this fact makes the technique well suited for geological analysis.

Black Oral Art Forms: Guided Group Interaction Techniques.

ERIC Educational Resources Information Center

Toldson, Ivory L.; Pasteur, Alfred B.

1981-01-01

Describes how oral art can positively influence the development of Black people through therapeutic guidance. Group techniques are suggested to stimulate the counselor's creative potential and enhance clients' self-worth Presents guidelines to enhance educational achievement and school retention, and develop determination and persistence. (JAC)

Contrast-enhanced magnetic resonance imaging of pulmonary lesions: description of a technique aiming clinical practice.

PubMed

Koenigkam-Santos, Marcel; Optazaite, Elzbieta; Sommer, Gregor; Safi, Seyer; Heussel, Claus Peter; Kauczor, Hans-Ulrich; Puderbach, Michael

2015-01-01

To propose a technique for evaluation of pulmonary lesions using contrast-enhanced MRI; to assess morphological patterns of enhancement and correlate quantitative analysis with histopathology. Thirty-six patients were prospectively studied. Volumetric-interpolated T1W images were obtained during consecutive breath holds after bolus triggered contrast injection. Volume coverage of first three acquisitions was limited (higher temporal resolution) and last acquisition obtained at 4th min. Two radiologists individually evaluated the patterns of enhancement. Region-of-interest-based signal intensity (SI)-time curves were created to assess quantitative parameters. Readers agreed moderately to substantially concerning lesions' enhancement pattern. SI-time curves could be created for all lesions. In comparison to benign, malignant lesions showed higher values of maximum enhancement, early peak, slope and 4th min enhancement. Early peak >15% showed 100% sensitivity to detect malignancy, maximum enhancement >40% showed 100% specificity. The proposed technique is robust, simple to perform and can be applied in clinical scenario. It allows visual evaluation of enhancement pattern/progression together with creation of SI-time curves and assessment of derived quantitative parameters. Perfusion analysis was highly sensitive to detect malignancy, in accordance to what is recommended by most recent guidelines on imaging evaluation of pulmonary lesions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Theorists and Techniques: Connecting Education Theories to Lamaze Teaching Techniques

PubMed Central

Podgurski, Mary Jo

2016-01-01

ABSTRACT Should childbirth educators connect education theory to technique? Is there more to learning about theorists than memorizing facts for an assessment? Are childbirth educators uniquely poised to glean wisdom from theorists and enhance their classes with interactive techniques inspiring participant knowledge and empowerment? Yes, yes, and yes. This article will explore how an awareness of education theory can enhance retention of material through interactive learning techniques. Lamaze International childbirth classes already prepare participants for the childbearing year by using positive group dynamics; theory will empower childbirth educators to address education through well-studied avenues. Childbirth educators can provide evidence-based learning techniques in their classes and create true behavioral change. PMID:26848246

Dual-energy contrast-enhanced mammography.

PubMed

Travieso Aja, M M; Rodríguez Rodríguez, M; Alayón Hernández, S; Vega Benítez, V; Luzardo, O P

2014-01-01

The degree of vascularization in breast lesions is related to their malignancy. For this reason, functional diagnostic imaging techniques have become important in recent years. Dual-energy contrast-enhanced mammography is a new, apparently promising technique in breast cancer that provides information about the degree of vascularization of the lesion in addition to the morphological information provided by conventional mammography. This article describes the state of the art for dual-energy contrast-enhanced mammography. Based on 15 months' clinical experience, we illustrate this review with clinical cases that allow us to discuss the advantages and limitations of this technique. Copyright © 2014 SERAM. Published by Elsevier Espana. All rights reserved.

Selectivity/Specificity Improvement Strategies in Surface-Enhanced Raman Spectroscopy Analysis

PubMed Central

Wang, Feng; Cao, Shiyu; Yan, Ruxia; Wang, Zewei; Wang, Dan; Yang, Haifeng

2017-01-01

Surface-enhanced Raman spectroscopy (SERS) is a powerful technique for the discrimination, identification, and potential quantification of certain compounds/organisms. However, its real application is challenging due to the multiple interference from the complicated detection matrix. Therefore, selective/specific detection is crucial for the real application of SERS technique. We summarize in this review five selective/specific detection techniques (chemical reaction, antibody, aptamer, molecularly imprinted polymers and microfluidics), which can be applied for the rapid and reliable selective/specific detection when coupled with SERS technique. PMID:29160798

Contrast-enhanced Spectral Mammography: Technique, Indications, and Clinical Applications.

PubMed

Bhimani, Chandni; Matta, Danielle; Roth, Robyn G; Liao, Lydia; Tinney, Elizabeth; Brill, Kristin; Germaine, Pauline

2017-01-01

Contrast-enhanced spectral mammography (CESM) combines the benefits of full field digital mammography with the concept of tumor angiogenesis. Technique and practical applications of CESM are discussed. An overview of the technique is followed by a demonstration of practical applications of CESM in our practice. We have successfully implemented CESM into our practice as a screening, diagnostic, staging, and treatment response tool. It is important to understand the technique of CESM and how to incorporate it into practice. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Scribliotherapy: Enhancing Communication among Students, Parents, and Teachers.

ERIC Educational Resources Information Center

Fine, Joyce C.

Researchers have long noted the psychologically-liberating effects of expressive language. This paper explores how a writing technique, scribliotherapy, enhances communication among students, parents, and teachers. Scribliography is the technique of matching children with books on the topics of their emotional concerns and writing their response…

Randomized response estimates for the 12-month prevalence of cognitive-enhancing drug use in university students.

PubMed

Dietz, Pavel; Striegel, Heiko; Franke, Andreas G; Lieb, Klaus; Simon, Perikles; Ulrich, Rolf

2013-01-01

To estimate the 12-month prevalence of cognitive-enhancing drug use. Paper-and-pencil questionnaire that used the randomized response technique. University in Mainz, Germany. A total of 2569 university students who completed the questionnaire. An anonymous, specialized questionnaire that used the randomized response technique was distributed to students at the beginning of classes and was collected afterward. From the responses, we calculated the prevalence of students taking drugs only to improve their cognitive performance and not to treat underlying mental disorders such as attention-deficit-hyperactivity disorder, depression, and sleep disorders. The estimated 12-month prevalence of using cognitive-enhancing drugs was 20%. Prevalence varied by sex (male 23.7%, female 17.0%), field of study (highest in students studying sports-related fields, 25.4%), and semester (first semester 24.3%, beyond first semester 16.7%). To our knowledge, this is the first time that the randomized response technique has been used to survey students about cognitive-enhancing drug use. Using the randomized response technique, our questionnaire provided data that showed a high 12-month prevalence of cognitive-enhancing drug use in German university students. Our study suggests that other direct survey techniques have underestimated the use of these drugs. Drug prevention programs need to be established at universities to address this issue. © 2013 Pharmacotherapy Publications, Inc.

Backscatter X-Ray Development for Space Vehicle Thermal Protection Systems

NASA Astrophysics Data System (ADS)

Bartha, Bence B.; Hope, Dale; Vona, Paul; Born, Martin; Corak, Tony

2011-06-01

The Backscatter X-Ray (BSX) imaging technique is used for various single sided inspection purposes. Previously developed BSX techniques for spray-on-foam insulation (SOFI) have been used for detecting defects in Space Shuttle External Tank foam insulation. The developed BSX hardware and techniques are currently being enhanced to advance Non-Destructive Evaluation (NDE) methods for future space vehicle applications. Various Thermal Protection System (TPS) materials were inspected using the enhanced BSX imaging techniques, investigating the capability of the method to detect voids and other discontinuities at various locations within each material. Calibration standards were developed for the TPS materials in order to characterize and develop enhanced BSX inspection capabilities. The ability of the BSX technique to detect both manufactured and natural defects was also studied and compared to through-transmission x-ray techniques. The energy of the x-ray, source to object distance, angle of x-ray, focal spot size and x-ray detector configurations were parameters playing a significant role in the sensitivity of the BSX technique to image various materials and defects. The image processing of the results also showed significant increase in the sensitivity of the technique. The experimental results showed BSX to be a viable inspection technique for space vehicle TPS systems.

Resolution enhancement of fiber Bragg grating temperature sensor using a cavity ring-down technique

NASA Astrophysics Data System (ADS)

Yarai, Atsushi; Hara, Katsuyuki

2018-02-01

A new technique for enhancing the measurement resolution of a fiber Bragg grating (FBG) temperature sensor is proposed. This technique uses a cavity ring-down approach to amplify optical intensity by accumulating unremarkable intensity changes. A wavelength-stabilized optical pulse with a width of 10 ns rotates several times inside an optical fiber loop that contains a FBG sensor. In other words, the loop system functions as an integrator of slight intensity transition. A temperature resolution of at least 0.02 °C was achieved at 20.0 °C. Resolution with this technique is at least five times higher than previous techniques.

Can contrast-enhanced ultrasonography improve Zone III REBOA placement for prehospital care?

PubMed

Chaudery, Muzzafer; Clark, James; Morrison, Jonathan J; Wilson, Mark H; Bew, Duncan; Darzi, Ara

2016-01-01

Torso hemorrhage is the primary cause of potentially preventable mortality in trauma. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has been advocated as an adjunct to bridge patients to definitive hemorrhage control. The primary aim of this study was to assess whether contrast-enhanced ultrasonography can improve the accuracy of REBOA placement in the infrarenal aorta (Zone III). A fluoroscopy-free "enhanced" Zone III REBOA technique was developed using a porcine cadaver model. A "standard" over-the-wire Seldinger technique was used, which was enhanced with the addition of a microbubble contrast medium to inflate the balloon, observed with ultrasonography. Following this, attending- and resident-level physicians were randomized into two groups. They were taught either the enhanced with ultrasonography guidance (Group A) or the standard measuring length of catheter insertion (Group B) technique as part of a human cadaver trauma skills course. Outcomes assessed included time (seconds) from insertion to inflation, accuracy, and missed targets. All results were benchmarked against three endovascular experts. There were 20 participants who performed REBOA with Group A (51 [31]) being significantly faster than Group B (90 [63]) (p = 0.003) and more accurate (p = 0.023) with no missed targets. Group B had five missed targets, the most common error being inflation within Zone II. For Zone III REBOA, contrast-enhanced ultrasonography technique is faster and more accurate than the standard technique. This may have value in time-critical and austere environments. Clinical studies are now required to evaluate this approach further.

The SQ3R Study Technique Enhances Comprehension of an Introductory Psychology Textbook.

ERIC Educational Resources Information Center

Chastain, Garvin; Thurber, Steven

1989-01-01

Examines the effectiveness of the SQ3R study technique in enhancing comprehension of material in an introductory psychology textbook. Finds significantly better performance on tests of recall or conceptual items for students using SQ3R than for those using individual study methods. (RS)

Use of Martial Art Exercises in Performance Enhancement Training.

ERIC Educational Resources Information Center

McClellan, Tim; Anderson, Warren

2002-01-01

Details some of the many martial arts training techniques and their potential applications for inclusion in performance enhancement programs, focusing on the benefits of martial training, the arts continuum, and martial arts training modes. The article concludes that the various martial arts techniques provide a stimulating and intuitively…

Practical techniques for enhancing the high-frequency MASW method

USDA-ARS?s Scientific Manuscript database

For soil exploration in the vadose zone, a high-frequency multi-channel analysis of surface waves (HF-MASW) method has been developed. In the study, several practical techniques were applied to enhance the overtone image of the HF-MASW method. They included (1) the self-adaptive MASW method using a ...

Privacy enhancing techniques - the key to secure communication and management of clinical and genomic data.

PubMed

De Moor, G J E; Claerhout, B; De Meyer, F

2003-01-01

To introduce some of the privacy protection problems related to genomics based medicine and to highlight the relevance of Trusted Third Parties (TTPs) and of Privacy Enhancing Techniques (PETs) in the restricted context of clinical research and statistics. Practical approaches based on two different pseudonymisation models, both for batch and interactive data collection and exchange, are described and analysed. The growing need of managing both clinical and genetic data raises important legal and ethical challenges. Protecting human rights in the realm of privacy, while optimising research potential and other statistical activities is a challenge that can easily be overcome with the assistance of a trust service provider offering advanced privacy enabling/enhancing solutions. As such, the use of pseudonymisation and other innovative Privacy Enhancing Techniques can unlock valuable data sources.

Privacy protection for clinical and genomic data. The use of privacy-enhancing techniques in medicine.

PubMed

Claerhout, B; DeMoor, G J E

2005-03-01

Privacy includes the right of individuals and organisations to determine for themselves when, how and to what extent information about them is communicated to others. The growing need of managing large amounts of both clinical and genetic data raises important legal and ethical challenges. This paper introduces some of the privacy-protection problems related to classical and genomic medicine, and highlights the relevance of trusted third parties and of privacy-enhancing techniques (PETs) in the context of data collection, e.g., for research. Practical approaches based on two pseudonymisation models, for both batch data collection and interactive data storage, are presented. The actual application of the described techniques today proves the possible benefits for medicine that innovative privacy-enhancing techniques can provide. Technical PET solutions can unlock valuable data sources, otherwise not available.

Comparison of contrast-enhanced T1-weighted FLAIR with BLADE, and spin-echo T1-weighted sequences in intracranial MRI.

PubMed

Alkan, Ozlem; Kizilkiliç, Osman; Yildirim, Tülin; Alibek, Sedat

2009-06-01

We compared periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER, BLADE) MR technique with spin echo (SE) technique for evaluation of artifacts, and detection and delineation of brain lesions. Contrast-enhanced T1-weighted fluid attenuated inversion recovery (FLAIR) images with BLADE technique (CE T1W-FLAIR BLADE) and contrast-enhanced T1-weighted SE (CE T1W-SE) were performed in 50 patients with intracranial enhancing lesions. These techniques were compared by two neuroradiologists for qualitative analysis of artifacts, lesion detectability, lesion delineation from adjacent structures, and preferred imaging technique; and for quantitative variables, i.e., lesion-to-background and lesion-to-cerebrospinal fluid (CSF) contrast-to-noise (CNR) ratios. Reader agreement was assessed by kappa statistics. All lesions depicted with the CE T1W-SE were also detected with the CE T1W-FLAIR BLADE technique. Delineation of lesions was better on CE T1W-FLAIR BLADE in the majority of patients. Flow-related artifacts were considerably reduced with CE T1W-FLAIR BLADE. A star-like artifact at the level of the 4(th) ventricle was noted on CE T1W-FLAIR BLADE but not on CE T1W-SE. The lesion-to-background CNR and lesion-to-CSF CNR did not show a statistically significant difference between the two techniques. CE T1W-FLAIR BLADE images were preferred by the observers over the CE T1w-SE images, indicating good interobserver agreement (k = 0.70). CE T1W-FLAIR BLADE technique is superior to CE T1WSE for delineation of lesions and reduction of flow-related artifacts, especially within the posterior fossa, and is preferred by readers. CE T1W-FLAIR BLADE may be an alternative approach to imaging, especially for posterior fossa lesions.

Penile Lengthening, Girth, and Size Preservation at the Time of Penile Prosthesis Insertion.

PubMed

Tran, Henry; Goldfarb, Robert; Ackerman, Anika; Valenzuela, Robert J

2017-07-01

Penile prosthetic devices are the gold standard treatment of medication-refractory erectile dysfunction. Inflatable penile prosthetic (IPP) devices have been available and used for more than four decades. Oftentimes, medical conditions causing erectile dysfunction also cause penile shortening, causing decreased patient quality of life. To identify and review all available penile lengthening procedures that can be performed at time of IPP insertion. An extensive, systematic literature review was performed using PubMed searching for key terms penile lengthening, inflatable penile prosthesis, penile girth, corporoplasty, glans augmentation, and penile enhancement; all articles with subjective and/or objective penile length outcomes were reviewed. A review of various techniques for penile length and girth preservation and enhancement during penile prosthesis insertion. Several advanced and novel techniques were found for penile length preservation and enhancement at time of IPP insertion, including the sub-coronal IPP insertion technique, and adjuvant maneuvers during insertion, such as the sliding technique, modified sliding technique, multiple slice technique, and circumferential incision and grafting. Other adjuvant techniques that can enhance perception of increased length include ventral phalloplasty, suprapubic lipectomy, and suspensory ligament release. Further enhancement can be obtained using augmentation corporoplasty and glans augmentation with hyaluronic acid and other fillers. The different techniques vary in complexity and could require specialized training and experience. Maximum length gain appears to be limited by the length of the neurovascular bundles. Overall, surgical penile lengthening procedures at time of IPP insertion appear safe and effective for treatment of patients with penile shortening and severe erectile dysfunction. These therapies can significantly improve patient self-esteem and quality of life in properly selected patients. Tran H, Goldfarb R, Ackerman A, Valenxuela RJ. Penile Lengthening, Girth and Size Preservation at the Time of Penile Prosthesis Insertion. Sex Med Rev 2017;5:403-412. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Diminishing-cues retrieval practice: A memory-enhancing technique that works when regular testing doesn't.

PubMed

Fiechter, Joshua L; Benjamin, Aaron S

2017-08-28

Retrieval practice has been shown to be a highly effective tool for enhancing memory, a fact that has led to major changes to educational practice and technology. However, when initial learning is poor, initial retrieval practice is unlikely to be successful and long-term benefits of retrieval practice are compromised or nonexistent. Here, we investigate the benefit of a scaffolded retrieval technique called diminishing-cues retrieval practice (Finley, Benjamin, Hays, Bjork, & Kornell, Journal of Memory and Language, 64, 289-298, 2011). Under learning conditions that favored a strong testing effect, diminishing cues and standard retrieval practice both enhanced memory performance relative to restudy. Critically, under learning conditions where standard retrieval practice was not helpful, diminishing cues enhanced memory performance substantially. These experiments demonstrate that diminishing-cues retrieval practice can widen the range of conditions under which testing can benefit memory, and so can serve as a model for the broader application of testing-based techniques for enhancing learning.

The computer treatment of remotely sensed data: An introduction to techniques which have geologic applications. [image enhancement and thematic classification in Brazil

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator); Paradella, W. R.; Vitorello, I.

1982-01-01

Several aspects of computer-assisted analysis techniques for image enhancement and thematic classification by which LANDSAT MSS imagery may be treated quantitatively are explained. On geological applications, computer processing of digital data allows, possibly, the fullest use of LANDSAT data, by displaying enhanced and corrected data for visual analysis and by evaluating and assigning each spectral pixel information to a given class.

Optical vs. electronic enhancement of remote sensing imagery

NASA Technical Reports Server (NTRS)

Colwell, R. N.; Katibah, E. F.

1976-01-01

Basic aspects of remote sensing are considered and a description is provided of the methods which are employed in connection with the optical or electronic enhancement of remote sensing imagery. The advantages and limitations of various image enhancement methods and techniques are evaluated. It is pointed out that optical enhancement methods and techniques are currently superior to electronic ones with respect to spatial resolution and equipment cost considerations. Advantages of electronic procedures, on the other hand, are related to a greater flexibility regarding the presentation of the information as an aid for the interpretation by the image analyst.

Digital processing of orbital radar data to enhance geologic structure - Examples from the Canadian Shield

NASA Technical Reports Server (NTRS)

Masuoka, Penny M.; Harris, Jeff; Lowman, Paul D., Jr.; Blodget, Herbert W.

1988-01-01

Various digital enhancement techniques for SAR are compared using SIR-B and Seasat images of the Canadian Shield. The three best methods for enhancing geological structure were found to be: (1) a simple linear contrast stretch; (2) a mean or median low-pass filter to reduce speckle prior to edge enhancement or a K nearest-neighbor average to cosmetically reduce speckle; and (3) a modification of the Moore-Waltz (1983) technique. Three look directions were coregistered and several means of data display were investigated as means of compensating for radar azimuth biasing.

Scale-model charge-transfer technique for measuring enhancement factors

NASA Technical Reports Server (NTRS)

Kositsky, J.; Nanevicz, J. E.

1991-01-01

Determination of aircraft electric field enhancement factors is crucial when using airborne field mill (ABFM) systems to accurately measure electric fields aloft. SRI used the scale model charge transfer technique to determine enhancement factors of several canonical shapes and a scale model Learjet 36A. The measured values for the canonical shapes agreed with known analytic solutions within about 6 percent. The laboratory determined enhancement factors for the aircraft were compared with those derived from in-flight data gathered by a Learjet 36A outfitted with eight field mills. The values agreed to within experimental error (approx. 15 percent).

Propulsion Health Monitoring for Enhanced Safety

NASA Technical Reports Server (NTRS)

Butz, Mark G.; Rodriguez, Hector M.

2003-01-01

This report presents the results of the NASA contract Propulsion System Health Management for Enhanced Safety performed by General Electric Aircraft Engines (GE AE), General Electric Global Research (GE GR), and Pennsylvania State University Applied Research Laboratory (PSU ARL) under the NASA Aviation Safety Program. This activity supports the overall goal of enhanced civil aviation safety through a reduction in the occurrence of safety-significant propulsion system malfunctions. Specific objectives are to develop and demonstrate vibration diagnostics techniques for the on-line detection of turbine rotor disk cracks, and model-based fault tolerant control techniques for the prevention and mitigation of in-flight engine shutdown, surge/stall, and flameout events. The disk crack detection work was performed by GE GR which focused on a radial-mode vibration monitoring technique, and PSU ARL which focused on a torsional-mode vibration monitoring technique. GE AE performed the Model-Based Fault Tolerant Control work which focused on the development of analytical techniques for detecting, isolating, and accommodating gas-path faults.

Topological study of nanomaterials using surface-enhanced ellipsometric contrast microscopy (SEEC)

NASA Astrophysics Data System (ADS)

Muckenhirn, Sylvain

2016-03-01

Innovations in nanotechnology are empowering scientists to deepen their understanding of physical, chemical and biological mechanisms. Powerful and precise characterization systems are essential to meet researchers' requirements. SEEC (Surface Enhanced Ellipsometric Contrast) microscopy is an innovative advanced optical technique based on ellipsometric and interference fringes of Fizeau principles. This technique offers live and label-free topographic imaging of organic, inorganic and biological samples with high Z resolution (down to 0.1nm thickness), and enhanced X-Y detection limit (down to 1.5nm width). This technique has been successfully applied to the study of nanometric films and structures, biological layers, and nano-objects. We applied SEEC technology to different applications explored below.

Computerized proof techniques for undergraduates

NASA Astrophysics Data System (ADS)

Smith, Christopher J.; Tefera, Akalu; Zeleke, Aklilu

2012-12-01

The use of computer algebra systems such as Maple and Mathematica is becoming increasingly important and widespread in mathematics learning, teaching and research. In this article, we present computerized proof techniques of Gosper, Wilf-Zeilberger and Zeilberger that can be used for enhancing the teaching and learning of topics in discrete mathematics. We demonstrate by examples how one can use these computerized proof techniques to raise students' interests in the discovery and proof of mathematical identities and enhance their problem-solving skills.

Enhancing Self-Efficacy and Performance: An Experimental Comparison of Psychological Techniques

ERIC Educational Resources Information Center

Wright, Bradley James; O'Halloran, Paul Daniel; Stukas, Arthur Anthony

2016-01-01

Purpose: We assessed how 6 psychological performance enhancement techniques (PETs) differentially improved self-efficacy (SE) and skill performance. We also assessed whether vicarious experiences and verbal persuasion as posited sources of SE (Bandura, 1982) were supported and, further, if the effects of the 6 PETs remained after controlling for…

A Phase-Only technique for enhancing the high-frequency MASW method

USDA-ARS?s Scientific Manuscript database

For soil exploration in the vadose zone, a high-frequency multi-channel analysis of surface waves (HF-MASW) method has been developed. In the study, several practical techniques were applied to enhance the overtone image of the HF-MASW method. They included (1) the self-adaptive MASW method using a ...

Flash X-ray with image enhancement applied to combustion events

NASA Astrophysics Data System (ADS)

White, K. J.; McCoy, D. G.

1983-10-01

Flow visualization of interior ballistic processes by use of X-rays has placed more stringent requirements on flash X-ray techniques. The problem of improving radiographic contrast of propellants in X-ray transparent chambers was studied by devising techniques for evaluating, measuring and reducing the effects of scattering from both the test object and structures in the test area. X-ray film and processing is reviewed and techniques for evaluating and calibrating these are outlined. Finally, after X-ray techniques were optimized, the application of image enhancement processing which can improve image quality is described. This technique was applied to X-ray studies of the combustion of very high burning rate (VHBR) propellants and stick propellant charges.

Buddhism and neuroethics: the ethics of pharmaceutical cognitive enhancement.

PubMed

Fenton, Andrew

2009-08-01

This paper integrates some Buddhist moral values, attitudes and self-cultivation techniques into a discussion of the ethics of cognitive enhancement technologies - in particular, pharmaceutical enhancements. Many Buddhists utilize meditation techniques that are both integral to their practice and are believed to enhance the cognitive and affective states of experienced practitioners. Additionally, Mahāyāna Buddhism's teaching on skillful means permits a liberal use of methods or techniques in Buddhist practice that yield insight into our selfnature or aid in alleviating or eliminating duhkha (i.e. dissatisfaction). These features of many, if not most, Buddhist traditions will inform much of the Buddhist assessment of pharmaceutical enhancements offered in this paper. Some Buddhist concerns about the effects and context of the use of pharmaceutical enhancements will be canvassed in the discussion. Also, the author will consider Buddhist views of the possible harms that may befall human and nonhuman research subjects, interference with a recipient's karma, the artificiality of pharmaceutical enhancements, and the possible motivations or intentions of healthy individuals pursuing pharmacological enhancement. Perhaps surprisingly, none of these concerns will adequately ground a reflective Buddhist opposition to the further development and continued use of pharmaceutical enhancements, either in principle or in practice. The author argues that Buddhists, from at least certain traditions - particularly Mahāyāna Buddhist traditions - should advocate the development or use of pharmaceutical enhancements if a consequence of their use is further insight into our self-nature or the reduction or alleviation of duhkha.

Synchrotron x-ray imaging visualization study of capillary-induced flow and critical heat flux on surfaces with engineered micropillars

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

Yu, Dong In; Kwak, Ho Jae; Noh, Hyunwoo

Over the past several decades, phenomena related to critical heat flux (CHF) on structured surfaces have received a large amount of attention from the research community. The purpose of such research has been to enhance the safety and efficiency of a variety of thermal systems. A number of theories have been put forward to explain the key CHF enhancement mechanisms on structured surfaces. However, these theories have not been confirmed experimentally due to limitations in the available visualization techniques and the complexity of the phenomena. To overcome the limitations of the previous visualization techniques and elucidate the CHF enhancement mechanismmore » on the structured surfaces, we introduce synchrotron X-ray imaging with high spatial (~2 μm) and time (~20,000 Hz) resolutions. Lastly, this technique has enabled us to confirm that capillary-induced flow is the key CHF enhancement mechanism on structured surfaces.« less

Towards high concentration enhancement of microfluidic temperature gradient focusing of sample solutes using combined AC and DC field induced Joule heating.

PubMed

Ge, Zhengwei; Wang, Wei; Yang, Chun

2011-04-07

It is challenging to continuously concentrate sample solutes in microfluidic channels. We present an improved electrokinetic technique for enhancing microfluidic temperature gradient focusing (TGF) of sample solutes using combined AC and DC field induced Joule heating effects. The introduction of an AC electric field component services dual functions: one is to produce Joule heat for generating temperature gradient; the other is to suppress electroosmotic flow. Consequently the required DC voltages for achieving sample concentration by Joule heating induced TGF are reduced, thereby leading to smaller electroosmotic flow (EOF) and thus backpressure effects. As a demonstration, the proposed technique can lead to concentration enhancement of sample solutes of more than 2500-fold, which is much higher than the existing literature reported microfluidic concentration enhancement by utilizing the Joule heating induced TGF technique.

Synchrotron x-ray imaging visualization study of capillary-induced flow and critical heat flux on surfaces with engineered micropillars

DOE PAGES

Yu, Dong In; Kwak, Ho Jae; Noh, Hyunwoo; ...

2018-02-23

Over the past several decades, phenomena related to critical heat flux (CHF) on structured surfaces have received a large amount of attention from the research community. The purpose of such research has been to enhance the safety and efficiency of a variety of thermal systems. A number of theories have been put forward to explain the key CHF enhancement mechanisms on structured surfaces. However, these theories have not been confirmed experimentally due to limitations in the available visualization techniques and the complexity of the phenomena. To overcome the limitations of the previous visualization techniques and elucidate the CHF enhancement mechanismmore » on the structured surfaces, we introduce synchrotron X-ray imaging with high spatial (~2 μm) and time (~20,000 Hz) resolutions. Lastly, this technique has enabled us to confirm that capillary-induced flow is the key CHF enhancement mechanism on structured surfaces.« less

Owning genetic information and gene enhancement techniques: why privacy and property rights may undermine social control of the human genome.

PubMed

Moore, A D

2000-04-01

In this article I argue that the proper subjects of intangible property claims include medical records, genetic profiles, and gene enhancement techniques. Coupled with a right to privacy these intangible property rights allow individuals a zone of control that will, in most cases, justifiably exclude governmental or societal invasions into private domains. I argue that the threshold for overriding privacy rights and intangible property rights is higher, in relation to genetic enhancement techniques and sensitive personal information, than is commonly suggested. Once the bar is raised, so-to-speak, the burden of overriding it is formidable. Thus many policy decisions that have been recently proposed or enacted--citywide audio and video surveillance, law enforcement DNA sweeps, genetic profiling, national bans on genetic testing and enhancement of humans, to name a few--will have to be backed by very strong arguments.

QRS classification and spatial combination for robust heart rate detection in low-quality fetal ECG recordings.

PubMed

Warmerdam, G; Vullings, R; Van Pul, C; Andriessen, P; Oei, S G; Wijn, P

2013-01-01

Non-invasive fetal electrocardiography (ECG) can be used for prolonged monitoring of the fetal heart rate (FHR). However, the signal-to-noise-ratio (SNR) of non-invasive ECG recordings is often insufficient for reliable detection of the FHR. To overcome this problem, source separation techniques can be used to enhance the fetal ECG. This study uses a physiology-based source separation (PBSS) technique that has already been demonstrated to outperform widely used blind source separation techniques. Despite the relatively good performance of PBSS in enhancing the fetal ECG, PBSS is still susceptible to artifacts. In this study an augmented PBSS technique is developed to reduce the influence of artifacts. The performance of the developed method is compared to PBSS on multi-channel non-invasive fetal ECG recordings. Based on this comparison, the developed method is shown to outperform PBSS for the enhancement of the fetal ECG.

Information-Adaptive Image Encoding and Restoration

NASA Technical Reports Server (NTRS)

Park, Stephen K.; Rahman, Zia-ur

1998-01-01

The multiscale retinex with color restoration (MSRCR) has shown itself to be a very versatile automatic image enhancement algorithm that simultaneously provides dynamic range compression, color constancy, and color rendition. A number of algorithms exist that provide one or more of these features, but not all. In this paper we compare the performance of the MSRCR with techniques that are widely used for image enhancement. Specifically, we compare the MSRCR with color adjustment methods such as gamma correction and gain/offset application, histogram modification techniques such as histogram equalization and manual histogram adjustment, and other more powerful techniques such as homomorphic filtering and 'burning and dodging'. The comparison is carried out by testing the suite of image enhancement methods on a set of diverse images. We find that though some of these techniques work well for some of these images, only the MSRCR performs universally well oil the test set.

Phacoemulsification using a chisel-shaped illuminator: enhanced depth trench, one-shot crack, and phaco cut.

PubMed

Wi, Jaemin; Seo, Hyejin; Lee, Jong Yeon; Nam, Dong Heun

2016-01-01

To evaluate the efficacy and outcomes of intracameral illuminator-assisted nucleofractis technique in cataract surgery. Since June 2012, this novel technique has been performed in all cataract cases by one surgeon (approximately 300 cases of various densities). Trenching continues until the posterior plate white reflex between an endonucleus and an epinucleus is identified (enhanced depth trench). After trenching, cracking is initiated with minimal separation force, and completion of cracking is confirmed by posterior capsule reflex (one-shot crack). With followability enhanced by an elliptical phaco mode, the divided nucleus is efficiently cut into small fragments by a chisel-shaped illuminator (phaco cut). We have not experienced any capsular bag or zonular complications, and the effective phacoemulsification time seemed to be shorter than that with the conventional technique. This technique simplifies the complete division of the nucleus, which is the most challenging step in safe and efficient phacoemulsification.

Minimally invasive esthetic ridge preservation with growth-factor enhanced bone matrix.

PubMed

Nevins, Marc L; Said, Sherif

2017-12-28

Extraction socket preservation procedures are critical to successful esthetic implant therapy. Conventional surgical approaches are technique sensitive and often result in alteration of the soft tissue architecture, which then requires additional corrective surgical procedures. This case series report presents the ability of flapless surgical techniques combined with a growth factor-enhanced bone matrix to provide esthetic ridge preservation at the time of extraction for compromised sockets. When considering esthetic dental implant therapy, preservation, or further enhancement of the available tissue support at the time of tooth extraction may provide an improved esthetic outcome with reduced postoperative sequelae and decreased treatment duration. Advances in minimally invasive surgical techniques combined with recombinant growth factor technology offer an alternative for bone reconstruction while maintaining the gingival architecture for enhanced esthetic outcome. The combination of freeze-dried bone allograft (FDBA) and rhPDGF-BB (platelet-derived growth factor-BB) provides a growth-factor enhanced matrix to induce bone and soft tissue healing. The use of a growth-factor enhanced matrix is an option for minimally invasive ridge preservation procedures for sites with advanced bone loss. Further studies including randomized clinical trials are needed to better understand the extent and limits of these procedures. The use of minimally invasive techniques with growth factors for esthetic ridge preservation reduces patient morbidity associated with more invasive approaches and increases the predictability for enhanced patient outcomes. By reducing the need for autogenous bone grafts the use of this technology is favorable for patient acceptance and ease of treatment process for esthetic dental implant therapy. © 2017 Wiley Periodicals, Inc.

Noncontrast-enhanced magnetic resonance renal angiography using a repetitive artery and venous labelling technique at 3 T: comparison with contrast-enhanced magnetic resonance angiography in subjects with normal renal function.

PubMed

Park, Sung Yoon; Kim, Chan Kyo; Kim, EunJu; Park, Byung Kwan

2015-02-01

To investigate the feasibility of noncontrast-enhanced MR angiography (NC-MRA) using the repetitive artery and venous labelling (RAVEL) technique to evaluate renal arteries compared to contrast-enhanced MR angiography (CE-MRA). Twenty-five subjects with normal renal function underwent NC-MRA using a RAVEL technique and CE-MRA at 3 T. Two independent readers analysed the MRA images. Image quality, number of renal arteries, presence or absence of an early branching vessel, and diameter of the main renal arteries were evaluated. The overall image quality of NC-MRA was fair or greater in 88% of right and 92% of left renal arteries, while it was 96% in both sides with CE-MRA. On NC-MRA, the number of renal arteries in all subjects was perfectly predicted by both readers. Sensitivity and specificity for predicting early branching vessels were 82% and 100% for reader 1 and 82% and 95% for reader 2. Inter-modality agreement for comparing the diameters of main renal arteries was good or excellent at all segments for both readers. Inter-reader agreement was moderate or good at all segments except at the right distal segment on NC-MRA. NC-MRA with the RAVEL technique at 3 T may have comparable diagnostic feasibility for evaluating renal arteries compared to CE-MRA. • Accurate pre-treatment evaluation of renal artery anatomy helps clinical decision-making. • NC-MRA using RAVEL offers acceptable imaging quality for renal artery evaluation. • The 3 T RAVEL technique provides excellent diagnostic performance for renal artery evaluation. • The 3 T RAVEL technique may be an alternative to contrast-enhanced MRA.

Wavelength modulated surface enhanced (resonance) Raman scattering for background-free detection.

PubMed

Praveen, Bavishna B; Steuwe, Christian; Mazilu, Michael; Dholakia, Kishan; Mahajan, Sumeet

2013-05-21

Spectra in surface-enhanced Raman scattering (SERS) are always accompanied by a continuum emission called the 'background' which complicates analysis and is especially problematic for quantification and automation. Here, we implement a wavelength modulation technique to eliminate the background in SERS and its resonant version, surface-enhanced resonance Raman scattering (SERRS). This is demonstrated on various nanostructured substrates used for SER(R)S. An enhancement in the signal to noise ratio for the Raman bands of the probe molecules is also observed. This technique helps to improve the analytical ability of SERS by alleviating the problem due to the accompanying background and thus making observations substrate independent.

Resolution enhancement in deep-tissue nanoparticle imaging based on plasmonic saturated excitation microscopy

NASA Astrophysics Data System (ADS)

Deka, Gitanjal; Nishida, Kentaro; Mochizuki, Kentaro; Ding, Hou-Xian; Fujita, Katsumasa; Chu, Shi-Wei

2018-03-01

Recently, many resolution enhancing techniques are demonstrated, but most of them are severely limited for deep tissue applications. For example, wide-field based localization techniques lack the ability of optical sectioning, and structured light based techniques are susceptible to beam distortion due to scattering/aberration. Saturated excitation (SAX) microscopy, which relies on temporal modulation that is less affected when penetrating into tissues, should be the best candidate for deep-tissue resolution enhancement. Nevertheless, although fluorescence saturation has been successfully adopted in SAX, it is limited by photobleaching, and its practical resolution enhancement is less than two-fold. Recently, we demonstrated plasmonic SAX which provides bleaching-free imaging with three-fold resolution enhancement. Here we show that the three-fold resolution enhancement is sustained throughout the whole working distance of an objective, i.e., 200 μm, which is the deepest super-resolution record to our knowledge, and is expected to extend into deeper tissues. In addition, SAX offers the advantage of background-free imaging by rejecting unwanted scattering background from biological tissues. This study provides an inspirational direction toward deep-tissue super-resolution imaging and has the potential in tumor monitoring and beyond.

Meta-Analysis of Free-Response Studies, 1992-2008: Assessing the Noise Reduction Model in Parapsychology

ERIC Educational Resources Information Center

Storm, Lance; Tressoldi, Patrizio E.; Di Risio, Lorenzo

2010-01-01

We report the results of meta-analyses on 3 types of free-response study: (a) ganzfeld (a technique that enhances a communication anomaly referred to as "psi"); (b) nonganzfeld noise reduction using alleged psi-enhancing techniques such as dream psi, meditation, relaxation, or hypnosis; and (c) standard free response (nonganzfeld, no noise…

Using the IGCRA (Individual, Group, Classroom Reflective Action) Technique to Enhance Teaching and Learning in Large Accountancy Classes

ERIC Educational Resources Information Center

Poyatos Matas, Cristina; Ng, Chew; Muurlink, Olav

2011-01-01

First year accounting has generally been perceived as one of the more challenging first year business courses for university students. Various Classroom Assessment Techniques (CATs) have been proposed to attempt to enrich and enhance student learning, with these studies generally positioning students as learners alone. This paper uses an…

Enhance Video Film using Retnix method

NASA Astrophysics Data System (ADS)

Awad, Rasha; Al-Zuky, Ali A.; Al-Saleh, Anwar H.; Mohamad, Haidar J.

2018-05-01

An enhancement technique used to improve the studied video quality. Algorithms like mean and standard deviation are used as a criterion within this paper, and it applied for each video clip that divided into 80 images. The studied filming environment has different light intensity (315, 566, and 644Lux). This different environment gives similar reality to the outdoor filming. The outputs of the suggested algorithm are compared with the results before applying it. This method is applied into two ways: first, it is applied for the full video clip to get the enhanced film; second, it is applied for every individual image to get the enhanced image then compiler them to get the enhanced film. This paper shows that the enhancement technique gives good quality video film depending on a statistical method, and it is recommended to use it in different application.

Optimization of single shot 3D breath-hold non-enhanced MR angiography of the renal arteries.

PubMed

Tan, Huan; Koktzoglou, Ioannis; Glielmi, Christopher; Galizia, Mauricio; Edelman, Robert R

2012-05-19

Cardiac and navigator-gated, inversion-prepared non-enhanced magnetic resonance angiography techniques can accurately depict the renal arteries without the need for contrast administration. However, the scan time and effectiveness of navigator-gated techniques depend on the subject respiratory pattern, which at times results in excessively prolonged scan times or suboptimal image quality. A single-shot 3D magnetization-prepared steady-state free precession technique was implemented to allow the full extent of the renal arteries to be depicted within a single breath-hold. Technical optimization of the breath-hold technique was performed with fourteen healthy volunteers. An alternative magnetization preparation scheme was tested to maximize inflow signal. Quantitative and qualitative comparisons were made between the breath-hold technique and the clinically accepted navigator-gated technique in both volunteers and patients on a 1.5 T scanner. The breath-hold technique provided an average of seven fold reduction in imaging time, without significant loss of image quality. Comparable single-to-noise and contrast-to-noise ratios of intra- and extra-renal arteries were found between the breath-hold and the navigator-gated techniques in volunteers. Furthermore, the breath-hold technique demonstrated good image quality for diagnostic purposes in a small number of patients in a pilot study. The single-shot, breath-hold technique offers an alternative to navigator-gated methods for non-enhanced renal magnetic resonance angiography. The initial results suggest a potential supplementary clinical role for the breath-hold technique in the evaluation of suspected renal artery diseases.

White Paper AGA: Advanced Imaging in Barrett's Esophagus.

PubMed

Sharma, Prateek; Brill, Joel; Canto, Marcia; DeMarco, Daniel; Fennerty, Brian; Gupta, Neil; Laine, Loren; Lieberman, David; Lightdale, Charles; Montgomery, Elizabeth; Odze, Robert; Tokar, Jeffrey; Kochman, Michael

2015-12-01

Enhanced imaging technologies such as narrow band imaging, flexible spectral imaging color enhancement, i-Scan, confocal laser endomicroscopy, and optical coherence tomography are readily available for use by endoscopists in routine clinical practice. In November 2014, the American Gastroenterological Association's Center for GI Innovation and Technology conducted a 2-day workshop to discuss endoscopic image enhancement technologies, focusing on their role in 2 specific clinical conditions (colon polyps and Barrett's esophagus) and on issues relating to training and implementation of these technologies (white papers). Although the majority of the studies that use enhanced imaging technologies have been positive, these techniques ideally need to be validated in larger cohorts and in community centers. As it stands today, detailed endoscopic examination with high-definition white-light endoscopy and random 4-quadrant biopsy remains the standard of care. However, the workshop panelists agreed that in the hands of endoscopists who have met the preservation and incorporation of valuable endoscopic innovation thresholds (diagnostic accuracy) with enhanced imaging techniques (specific technologies), use of the technique in Barrett's esophagus patients is appropriate. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

The Increasing Interest of ANAMMOX Research in China: Bacteria, Process Development, and Application

PubMed Central

Chai, Li-Yuan; Tang, Chong-Jian; Zheng, Ping; Min, Xiao-Bo; Yang, Zhi-Hui; Song, Yu-Xia

2013-01-01

Nitrogen pollution created severe environmental problems and increasingly has become an important issue in China. Since the first discovery of ANAMMOX in the early 1990s, this related technology has become a promising as well as sustainable bioprocess for treating strong nitrogenous wastewater. Many Chinese research groups have concentrated their efforts on the ANAMMOX research including bacteria, process development, and application during the past 20 years. A series of new and outstanding outcomes including the discovery of new ANAMMOX bacterial species (Brocadia sinica), sulfate-dependent ANAMMOX bacteria (Anammoxoglobus sulfate and Bacillus benzoevorans), and the highest nitrogen removal performance (74.3–76.7 kg-N/m3/d) in lab scale granule-based UASB reactors around the world were achieved. The characteristics, structure, packing pattern and floatation mechanism of the high-rate ANAMMOX granules in ANAMMOX reactors were also carefully illustrated by native researchers. Nowadays, some pilot and full-scale ANAMMOX reactors were constructed to treat different types of ammonium-rich wastewater including monosodium glutamate wastewater, pharmaceutical wastewater, and leachate. The prime objective of the present review is to elucidate the ongoing ANAMMOX research in China from lab scale to full scale applications, comparative analysis, and evaluation of significant findings and to set a design to usher ANAMMOX research in culmination. PMID:24381935

Endoparasites of Wild Mammals Sheltered in Wildlife Hospitals and Rehabilitation Centres in Greece

PubMed Central

Liatis, Theophanes K.; Monastiridis, Antonios A.; Birlis, Panagiotis; Prousali, Sophia; Diakou, Anastasia

2017-01-01

Wildlife parasitic diseases represent an important field of investigation as they may have a significant impact on wild animals’ health and fitness, and may also have zoonotic implications. This study aimed to investigate the occurrence of endoparasites in wild mammals admitted to wildlife hospitals and rehabilitation centres in Greece. Sixty-five animals belonging to 17 species and originated from various areas of continental and insular Greece were included in the survey. The most numerous animal species examined were hedgehogs (n = 19), red foxes (n = 16), and European roe deer (n = 6). Faecal samples were collected individually and examined by floatation and sedimentation method. Parasites were found in 46 (70.7%) of the animals. Most parasites found in canids, felids, and ruminants are of great relevance to the domestic animals’ health and some of them are also of zoonotic importance. To the best of the author’s knowledge, this is the first report of endoparasites in hedgehogs, roe deers, fallow deers, badgers, and bats, and the first report of the pulmonary nematode Troglostrongylus brevior in a wild cat in Greece. The significance of the parasites found in each animal species in regard to their health and their relevance to domestic animals and human health is discussed. PMID:29326954

Evidence for an early wet Moon from experimental crystallization of the lunar magma ocean

NASA Astrophysics Data System (ADS)

Lin, Yanhao; Tronche, Elodie J.; Steenstra, Edgar S.; van Westrenen, Wim

2017-01-01

The Moon is thought to have been covered initially by a deep magma ocean, its gradual solidification leading to the formation of the plagioclase-rich highland crust. We performed a high-pressure, high-temperature experimental study of lunar mineralogical and geochemical evolution during magma ocean solidification that yields constraints on the presence of water in the earliest lunar interior. In the experiments, a deep layer containing both olivine and pyroxene is formed in the first ~50% of crystallization, β-quartz forms towards the end of crystallization, and the last per cent of magma remaining is extremely iron rich. In dry experiments, plagioclase appears after 68 vol.% solidification and yields a floatation crust with a thickness of ~68 km, far above the observed average of 34-43 km based on lunar gravity. The volume of plagioclase formed during crystallization is significantly less in water-bearing experiments. Using the relationship between magma water content and the resulting crustal thickness in the experiments, and considering uncertainties in initial lunar magma ocean depth, we estimate that the Moon may have contained at least 270 to 1,650 ppm water at the time of magma ocean crystallization, suggesting the Earth-Moon system was water-rich from the start.

The effect of the natural bentonite to reduce COD in palm oil mill effluent by using a hybrid adsorption-flotation method

NASA Astrophysics Data System (ADS)

Dewi, Ratni; Sari, Ratna; Syafruddin

2017-06-01

Palm oil mill effluent is waste produced from palm oil processing activities. This waste are comingfrom condensate water, process water and hydrocyclone water. The high levels of contaminants in the palm oil mill effluent causes the waste becomes inappropriate to be discharged to water body before processing, one of the most major contaminants in wastewater is fats, oils and COD.This study investigated the effectiveness of chemically activated bentonite that serves as an alternative to reduce the COD in adsorption and floatation based palm oil effluent waste processing. Natural bentonite was activated by using nitrit acid and benzene. In the existing adsorption material to improve COD reduction capability whereas the flotation method was used to further remove residual effluent which is still remain after the adsorption process. An adsorption columns which operated in batch was used in the present study. By varying the circulation time and adsorbent treatment (activated and non-activated), it was shown that percentage of COD reduction reached 75% at the circulation time of 180 minutes for non activated adsorbent. On the other hand the percentof COD reduction in adsorption and flotation process using activated bentonite reached as high as 88% and 93% at the circulation time of 180 minutes.

Design and manufacture of 8.4 m primary mirror segments and supports for the GMT

NASA Astrophysics Data System (ADS)

Martin, H. M.; Angel, J. R. P.; Burge, J. H.; Cuerden, B.; Davison, W. B.; Johns, M.; Kingsley, J. S.; Kot, L. B.; Lutz, R. D.; Miller, S. M.; Shectman, S. A.; Strittmatter, P. A.; Zhao, C.

2006-06-01

The design, manufacture and support of the primary mirror segments for the GMT build on the successful primary mirror systems of the MMT, Magellan and Large Binocular telescopes. The mirror segment and its support system are based on a proven design, and the experience gained in the existing telescopes has led to significant refinements that will provide even better performance in the GMT. The first 8.4 m segment has been cast at the Steward Observatory Mirror Lab, and optical processing is underway. Measurement of the off-axis surface is the greatest challenge in the manufacture of the segments. A set of tests that meets the requirements has been defined and the concepts have been developed in some detail. The most critical parts of the tests have been demonstrated in the measurement of a 1.7 m off-axis prototype. The principal optical test is a full-aperture, high-resolution null test in which a hybrid reflective-diffractive null corrector compensates for the 14 mm aspheric departure of the off-axis segment. The mirror support uses the same synthetic floatation principle as the MMT, Magellan, and LBT mirrors. Refinements for GMT include 3-axis actuators to accommodate the varying orientations of segments in the telescope.

The in vitro interactions between serum lipoproteins and proteoglycans of the neointima of rabbit aorta after a single balloon catheter injury.

PubMed

Alavi, M Z; Richardson, M; Moore, S

1989-02-01

The effect of injury-induced alterations in the aortic neointimal proteoglycans on their binding with homologous serum lipoproteins was examined. Proteoglycans of the aortic intimal-medial tissues of rabbits that had undergone denudation with a balloon catheter 12 weeks earlier were isolated after homogenization of the tissues in 0.33 M sucrose, ultracentrifugation and subsequently by gel-exclusion chromatography. Lipoproteins from the plasma of healthy donors were prepared by sequential, ultracentrifugal floatation after density adjustment with KBr. To study the interactions, aliquots of electrophoretically pure very low-density lipoproteins (VLDL, d less than 1.006 g/ml), low-density lipoproteins (LDL, d = 1.019-1.063 g/ml), or high-density lipoproteins (HDL, d = 1.210 g/ml) were incubated with proteoglycans in the presence of Ca++ and Mg++ at 4 C. The amount of cholesterol found in the resulting pellet was measured as a marker of the binding capacity of the proteoglycans. Among lipoprotein fractions both VLDL and LDL showed strong binding with proteoglycans, whereas no appreciable binding was observed when incubation experiments were done with HDL. There were significant differences in the lipoprotein binding capacity of proteoglycan of control and injured animals, indicating that injury induced changes in proteoglycan composition exert profound influences on their ionic interactions.

Evaluation of an active seating system for pressure relief.

PubMed

Koo, T K; Mak, A F; Lee, Y L

1995-01-01

In the first part of this study, the inflation-pressure and interface-pressure profiles of an active cushion system, the Talley active air bellows cushion, were examined continuously for one complete working cycle using the dynamic pressure monitor. The relationship between the inflation pressure and the interface pressure was explored. A well-defined relationship was found in the areas directly over the air bellows. In the second part of this study, the pressure-relieving characteristics of the active cushion were assessed quantitatively and compared to two types of passive cushions--the Roho high-profile air floatation cushion and the polyurethane (PU) foam cushion. Eight non-disabled subjects were positioned on the active cushion at two inflation-pressure levels--30 mmHg and 60 mmHg, or on the Roho or the PU foam cushions. Interface pressures were recorded using the Oxford pressure monitor. For the active cushion it was shown that the higher the inflation pressure was, the better the pressure-relieving characteristics seemed to be. In general, the pressure-relieving characteristics of the active cushion were not as good as those of the passive cushions being tested. The active cushion could alter the pressures over the ischial tuberosities cyclically but the amount of pressure alternation depended on the relative position of the ischial tuberosities and the air bellows.

Floating elementary osmotic pump tablet (FEOPT) for controlled delivery of diethylcarbamazine citrate: a water-soluble drug.

PubMed

Khan, Zulfequar Ahamad; Tripathi, Rahul; Mishra, Brahmeshwar

2011-12-01

The present work investigates the feasibility of the design of a novel floating elementary osmotic pump tablet (FEOPT) to prolong the gastric residence of a highly water-soluble drug. Diethylcarbamazine citrate (DEC) was chosen as a model drug. The FEOPT consisted of an osmotic core (DEC, mannitol, and hydrophilic polymers) coated with a semipermeable layer (cellulose acetate) and a gas-generating gelling layer (sodium bicarbonate, hydrophilic polymers) followed by a polymeric film (Eudragit RL 30D). The effect of formulation variables such as concentration of polymers, types of diluent, and coat thickness of semipermeable membrane was evaluated in terms of physical parameters, floating lag time, duration of floatation, and in vitro drug release. The Fourier transform infrared and X-ray diffraction analysis were carried out to study the physicochemical changes in the drug excipients powder blend. The integrity of the orifice and polymeric film layer was confirmed from scanning electron microscopy image. All the developed FEOPT showed floating lag time of less than 8 min and floating duration of 24 h. A zero-order drug release could be attained for DEC. The formulations were found to be stable up to 3 months of stability testing at 40°C/75% relative humidity.

GPI-anchored GFP signals Ca2+ but is homogeneously distributed on the cell surface.

PubMed

Hiscox, Stephen; Hallett, Maurice B; Morgan, B Paul; van den Berg, Carmen W

2002-05-03

Glycosyl-phosphatidylinositol (GPI)-anchored proteins are unique in that they penetrate only the outer leaflet of the plasma membrane but are still able to mediate intracellular signalling events following antibody-induced ligation. Detergent solubilisation studies suggest that microdomains exist at the cell surface within which are sequestered GPI-linked proteins. Here we report the construction and expression of a fluorescent GPI anchor on the surface of CHO, EL4, and U937 cells by fusing green fluorescent protein (GFP) to the GPI-attachment site of CD59. The resultant GFP-GPI has properties comparable to that of endogenously expressed GPI-anchored molecules as shown by Triton X-114 partitioning. However, sucrose gradient floatation showed that GFP-GPI was only partially resistant to detergent solubilisation. Furthermore confocal scanning laser microscopy revealed a homogeneous distribution of GFP-GPI at the cell surface, which only became clustered following cross-linking of the GPI anchor via an anti-GFP antibody. Surprisingly, GFP-GPI signalled Ca2+ change upon cross-linking demonstrating its signalling competence. Our results suggest that the GPI-anchor itself does not confer a clustered distribution to molecules but that clustering occurs following ligation with antibody, which allows the protein to become Ca2+ signalling competent. Copyright 2002 Elsevier Science (USA).

Cardiac output increases prior to development of pulmonary edema after re-expansion of spontaneous pneumothorax.

PubMed

Tan, H C; Mak, K H; Johan, A; Wang, Y T; Poh, S C

2002-06-01

Pulmonary edema following reexpansion of spontaneous pneumothorax is an uncommon complication. The underlying mechanism of this condition is unclear. We report the hemodynamic characteristics in a series of 7 male patients with spontaneous large (>50%) pneumothoraces of > or = 24 h and correlate the changes with reexpansion pulmonary edema (REPE). A pulmonary artery floatation catheter was inserted and hemodynamic data were obtained before therapeutic chest tube insertion, 1 h after chest tube insertion and the following day. Four (57%) patients developed REPE. There was a tendency for larger pneumothorax to develop REPE. Capillary wedge pressure did not change significantly 1 h after the insertion of chest tube in all our patients. Cardiac output increased significantly in patients who developed REPE compared to those who did not (+ 1.06 l/min vs -0.27 l/min; P = 0.03) 1 h after insertion of chest tube. One patient did not develop pulmonary edema despite having a large (> 80%) pneumothorax. His cardiac output did not rise 1 h after chest tube insertion. REPE is not an uncommon complication following chest tube drainage in patients with large and long-standing pneumothorax. The increase in cardiac output after chest tube insertion may be associated with subsequent development of REPE.

The synthesis and characterization of fatty acid salts of chitosan as novel matrices for prolonged intragastric drug delivery.

PubMed

Bani-Jaber, Ahmad; Hamdan, Imad; Alkawareek, Mahmoud

2012-07-01

The aim of this study was to prepare fatty acid salts of chitosan (CS) and to evaluate the salts as matrices for sustained drug release and prolonged gastric retention. CS-laurate and CS-palmitate were formed by mixing saturated CS solution and aqueous solutions of sodium laurate and sodium palmitate, respectively, and collected by centrifugation. They were characterized using Fourier-transform infrared spectroscopy and differential scanning calorimetry. Different matrices as effervescent tablets were prepared using each of these CS-salts, CS and the corresponding physical mixtures of CS and the fatty acids. Sodium bicarbonate as an effervescent agent and ranitidine HCl as a model drug were incorporated into these matrices. In vitro buoyancy and drug dissolution were studied for the matrices in 0.1 M HCl. Tablets with fatty acid salts of CS showed both rapid and prolonged buoyancy (> 8 h). Comparatively, CS tablets exhibited a short floatation period (< 2 h) and tablets were completely disintegrated within 1 h of soaking. In addition, slow and prolonged drug release was achieved from tablets of fatty acid salts of CS with average drug release of 80.1 and 71.8% for CS-laurate and CS-palmitate, respectively. Rapid drug release (> 80% at 1 h) was exhibited by tablets with CS or the physical mixtures.

Development of a gastroretentive pulsatile drug delivery platform.

PubMed

Thitinan, Sumalee; McConville, Jason T

2012-04-01

To develop a novel gastroretentive pulsatile drug delivery platform by combining the advantages of floating dosage forms for the stomach and pulsatile drug delivery systems. A gastric fluid impermeable capsule body was used as a vessel to contain one or more drug layer(s) as well as one or more lag-time controlling layer(s). A controlled amount of air was sealed in the innermost portion of the capsule body to reduce the overall density of the drug delivery platform, enabling gastric floatation. An optimal mass fill inside the gastric fluid impermeable capsule body enabled buoyancy in a vertical orientation to provide a constant surface area for controlled erosion of the lag-time controlling layer. The lag-time controlling layer consisted of a swellable polymer, which rapidly formed a gel to seal the mouth of capsule body and act as a barrier to gastric fluid ingress. By varying the composition of the lag-time controlling layer, it was possible to selectively program the onset of the pulsatile delivery of a drug. This new delivery platform offers a new method of delivery for a variety of suitable drugs targeted in chronopharmaceutical therapy. This strategy could ultimately improve drug efficacy and patient compliance, and reduce harmful side effects by scaling back doses of drug administered. © 2012 The Authors. JPP © 2012 Royal Pharmaceutical Society.

Polarization and Color Filtering Applied to Enhance Photogrammetric Measurements of Reflective Surfaces

NASA Technical Reports Server (NTRS)

Wells, Jeffrey M.; Jones, Thomas W.; Danehy, Paul M.

2005-01-01

Techniques for enhancing photogrammetric measurement of reflective surfaces by reducing noise were developed utilizing principles of light polarization. Signal selectivity with polarized light was also compared to signal selectivity using chromatic filters. Combining principles of linear cross polarization and color selectivity enhanced signal-to-noise ratios by as much as 800 fold. More typical improvements with combining polarization and color selectivity were about 100 fold. We review polarization-based techniques and present experimental results comparing the performance of traditional retroreflective targeting materials, cornercube targets returning depolarized light, and color selectivity.

Development of optimized techniques and requirements for computer enhancement of structural weld radiographs. Volume 1: Technical report

NASA Technical Reports Server (NTRS)

Adams, J. R.; Hawley, S. W.; Peterson, G. R.; Salinger, S. S.; Workman, R. A.

1971-01-01

A hardware and software specification covering requirements for the computer enhancement of structural weld radiographs was considered. Three scanning systems were used to digitize more than 15 weld radiographs. The performance of these systems was evaluated by determining modulation transfer functions and noise characteristics. Enhancement techniques were developed and applied to the digitized radiographs. The scanning parameters of spot size and spacing and film density were studied to optimize the information content of the digital representation of the image.

Novel techniques for optical sensor using single core multi-layer structures for electric field detection

NASA Astrophysics Data System (ADS)

Ali, Amir R.; Kamel, Mohamed A.

2017-05-01

This paper studies the effect of the electrostriction force on the single optical dielectric core coated with multi-layers based on whispering gallery mode (WGM). The sensing element is a dielectric core made of polymeric material coated with multi-layers having different dielectric and mechanical properties. The external electric field deforming the sensing element causing shifts in its WGM spectrum. The multi-layer structures will enhance the body and the pressure forces acting on the core of the sensing element. Due to the gradient on the dielectric permittivity; pressure forces at the interface between every two layers will be created. Also, the gradient on Young's modulus will affect the overall stiffness of the optical sensor. In turn the sensitivity of the optical sensor to the electric field will be increased when the materials of each layer selected properly. A mathematical model is used to test the effect for that multi-layer structures. Two layering techniques are considered to increase the sensor's sensitivity; (i) Pressure force enhancement technique; and (ii) Young's modulus reduction technique. In the first technique, Young's modulus is kept constant for all layers, while the dielectric permittivity is varying. In this technique the results will be affected by the value dielectric permittivity of the outer medium surrounding the cavity. If the medium's dielectric permittivity is greater than that of the cavity, then the ascending ordered layers of the cavity will yield the highest sensitivity (the core will have the smallest dielectric permittivity) to the applied electric field and vice versa. In the second technique, Young's modulus is varying along the layers, while the dielectric permittivity has a certain constant value per layer. On the other hand, the descending order will enhance the sensitivity in the second technique. Overall, results show the multi-layer cavity based on these techniques will enhance the sensitivity compared to the typical polymeric optical sensor.

Integrating Internet Video Conferencing Techniques and Online Delivery Systems with Hybrid Classes to Enhance Student Interaction and Learning in Accelerated Programs

ERIC Educational Resources Information Center

Beckwith, E. George; Cunniff, Daniel T.

2009-01-01

Online course enrollment has increased dramatically over the past few years. The authors cite the reasons for this rapid growth and the opportunities open for enhancing teaching/learning techniques such as video conferencing and hybrid class combinations. The authors outlined an example of an accelerated learning, eight-class session course…

IMAGE ENHANCEMENT FOR IMPAIRED VISION: THE CHALLENGE OF EVALUATION

PubMed Central

PELI, ELI; WOODS, RUSSELL L

2009-01-01

With the aging of the population, the prevalence of eye diseases and thus of vision impairment is increasing. The TV watching habits of people with vision impairments are comparable to normally sighted people1, however their vision loss prevents them from fully benefiting from this medium. For over 20 years we have been developing video image-enhancement techniques designed to assist people with visual impairments, particularly those due to central retinal vision loss. A major difficulty in this endeavor is the lack of evaluation techniques to assess and compare the effectiveness of various enhancement methods. This paper reviews our approaches to image enhancement and the results we have obtained, with special emphasis on the difficulties encountered in the evaluation of the benefits of enhancement and the solutions we have developed to date. PMID:20161188

Photo-reconnaissance applications of computer processing of images.

NASA Technical Reports Server (NTRS)

Billingsley, F. C.

1972-01-01

Discussion of imaging processing techniques for enhancement and calibration of Jet Propulsion Laboratory imaging experiment pictures returned from NASA space vehicles such as Ranger, Mariner and Surveyor. Particular attention is given to data transmission, resolution vs recognition, and color aspects of digital data processing. The effectiveness of these techniques in applications to images from a wide variety of sources is noted. It is anticipated that the use of computer processing for enhancement of imagery will increase with the improvement and cost reduction of these techniques in the future.

Rapid and sensitive phenotypic marker detection on breast cancer cells using surface-enhanced Raman scattering (SERS) imaging.

PubMed

Lee, Sangyeop; Chon, Hyangah; Lee, Jiyoung; Ko, Juhui; Chung, Bong Hyun; Lim, Dong Woo; Choo, Jaebum

2014-01-15

We report a surface-enhanced Raman scattering (SERS)-based cellular imaging technique to detect and quantify breast cancer phenotypic markers expressed on cell surfaces. This technique involves the synthesis of SERS nano tags consisting of silica-encapsulated hollow gold nanospheres (SEHGNs) conjugated with specific antibodies. Hollow gold nanospheres (HGNs) enhance SERS signal intensity of individual particles by localizing surface electromagnetic fields through pinholes in the hollow particle structures. This capacity to enhance imaging at the level of single molecules permits the use of HGNs to detect specific biological markers expressed in living cancer cells. In addition, silica encapsulation greatly enhances the stability of nanoparticles. Here we applied a SERS-based imaging technique using SEHGNs in the multiplex imaging of three breast cancer cell phenotypes. Expression of epidermal growth factor (EGF), ErbB2, and insulin-like growth factor-1 (IGF-1) receptors were assessed in the MDA-MB-468, KPL4 and SK-BR-3 human breast cancer cell lines. SERS imaging technology described here can be used to test the phenotype of a cancer cell and quantify proteins expressed on the cell surface simultaneously. Based on results, this technique may enable an earlier diagnosis of breast cancer than is currently possible and offer guidance in treatment. © 2013 Elsevier B.V. All rights reserved.

Fingerprint pattern restoration by digital image processing techniques.

PubMed

Wen, Che-Yen; Yu, Chiu-Chung

2003-09-01

Fingerprint evidence plays an important role in solving criminal problems. However, defective (lacking information needed for completeness) or contaminated (undesirable information included) fingerprint patterns make identifying and recognizing processes difficult. Unfortunately. this is the usual case. In the recognizing process (enhancement of patterns, or elimination of "false alarms" so that a fingerprint pattern can be searched in the Automated Fingerprint Identification System (AFIS)), chemical and physical techniques have been proposed to improve pattern legibility. In the identifying process, a fingerprint examiner can enhance contaminated (but not defective) fingerprint patterns under guidelines provided by the Scientific Working Group on Friction Ridge Analysis, Study and Technology (SWGFAST), the Scientific Working Group on Imaging Technology (SWGIT), and an AFIS working group within the National Institute of Justice. Recently, the image processing techniques have been successfully applied in forensic science. For example, we have applied image enhancement methods to improve the legibility of digital images such as fingerprints and vehicle plate numbers. In this paper, we propose a novel digital image restoration technique based on the AM (amplitude modulation)-FM (frequency modulation) reaction-diffusion method to restore defective or contaminated fingerprint patterns. This method shows its potential application to fingerprint pattern enhancement in the recognizing process (but not for the identifying process). Synthetic and real images are used to show the capability of the proposed method. The results of enhancing fingerprint patterns by the manual process and our method are evaluated and compared.

Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method.

PubMed

Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

2018-01-17

Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat 'brighter' than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

Bone surface enhancement in ultrasound images using a new Doppler-based acquisition/processing method

NASA Astrophysics Data System (ADS)

Yang, Xu; Tang, Songyuan; Tasciotti, Ennio; Righetti, Raffaella

2018-01-01

Ultrasound (US) imaging has long been considered as a potential aid in orthopedic surgeries. US technologies are safe, portable and do not use radiations. This would make them a desirable tool for real-time assessment of fractures and to monitor fracture healing. However, image quality of US imaging methods in bone applications is limited by speckle, attenuation, shadow, multiple reflections and other imaging artifacts. While bone surfaces typically appear in US images as somewhat ‘brighter’ than soft tissue, they are often not easily distinguishable from the surrounding tissue. Therefore, US imaging methods aimed at segmenting bone surfaces need enhancement in image contrast prior to segmentation to improve the quality of the detected bone surface. In this paper, we present a novel acquisition/processing technique for bone surface enhancement in US images. Inspired by elastography and Doppler imaging methods, this technique takes advantage of the difference between the mechanical and acoustic properties of bones and those of soft tissues to make the bone surface more easily distinguishable in US images. The objective of this technique is to facilitate US-based bone segmentation methods and improve the accuracy of their outcomes. The newly proposed technique is tested both in in vitro and in vivo experiments. The results of these preliminary experiments suggest that the use of the proposed technique has the potential to significantly enhance the detectability of bone surfaces in noisy ultrasound images.

Effect of scene illumination conditions on digital enhancement techniques of multispectral scanner LANDSAT images

NASA Technical Reports Server (NTRS)

Parada, N. D. J.; Novo, E. M. L. M.

1983-01-01

Two sets of MSS/LANDSAT data with solar elevation ranging from 22 deg to 41 deg were used at the Image-100 System to implement the Eliason et alii technique for extracting the topographic modulation component. An unsupervised cluster analysis was used to obtain an average brightness image for each channel. Analysis of the enhanced imaged shows that the technique for extracting topographic modulation component is more appropriated to MSS data obtained under high sun elevation ngles. Low sun elevation increases the variance of each cluster so that the average brightness doesn't represent its albedo proprties. The topographic modulation component applied to low sun elevation angle damages rather than enhance topographic information. Better results were produced for channels 4 and 5 than for channels 6 and 7.

Surface- and Tip-Enhanced Raman Spectroscopy in Catalysis

PubMed Central

2016-01-01

Surface- and tip-enhanced Raman spectroscopy (SERS and TERS) techniques exhibit highly localized chemical sensitivity, making them ideal for studying chemical reactions, including processes at catalytic surfaces. Catalyst structures, adsorbates, and reaction intermediates can be observed in low quantities at hot spots where electromagnetic fields are the strongest, providing ample opportunities to elucidate reaction mechanisms. Moreover, under ideal measurement conditions, it can even be used to trigger chemical reactions. However, factors such as substrate instability and insufficient signal enhancement still limit the applicability of SERS and TERS in the field of catalysis. By the use of sophisticated colloidal synthesis methods and advanced techniques, such as shell-isolated nanoparticle-enhanced Raman spectroscopy, these challenges could be overcome. PMID:27075515

Data analysis techniques

NASA Technical Reports Server (NTRS)

Park, Steve

1990-01-01

A large and diverse number of computational techniques are routinely used to process and analyze remotely sensed data. These techniques include: univariate statistics; multivariate statistics; principal component analysis; pattern recognition and classification; other multivariate techniques; geometric correction; registration and resampling; radiometric correction; enhancement; restoration; Fourier analysis; and filtering. Each of these techniques will be considered, in order.

Probabilistic retinal vessel segmentation

NASA Astrophysics Data System (ADS)

Wu, Chang-Hua; Agam, Gady

2007-03-01

Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

Cavity-enhanced Raman microscopy of individual carbon nanotubes

PubMed Central

Hümmer, Thomas; Noe, Jonathan; Hofmann, Matthias S.; Hänsch, Theodor W.; Högele, Alexander; Hunger, David

2016-01-01

Raman spectroscopy reveals chemically specific information and provides label-free insight into the molecular world. However, the signals are intrinsically weak and call for enhancement techniques. Here, we demonstrate Purcell enhancement of Raman scattering in a tunable high-finesse microcavity, and utilize it for molecular diagnostics by combined Raman and absorption imaging. Studying individual single-wall carbon nanotubes, we identify crucial structural parameters such as nanotube radius, electronic structure and extinction cross-section. We observe a 320-times enhanced Raman scattering spectral density and an effective Purcell factor of 6.2, together with a collection efficiency of 60%. Potential for significantly higher enhancement, quantitative signals, inherent spectral filtering and absence of intrinsic background in cavity-vacuum stimulated Raman scattering render the technique a promising tool for molecular imaging. Furthermore, cavity-enhanced Raman transitions involving localized excitons could potentially be used for gaining quantum control over nanomechanical motion and open a route for molecular cavity optomechanics. PMID:27402165

Dose to the contralateral breast: a comparison of two techniques using the enhanced dynamic wedge versus a standard wedge.

PubMed

Warlick, W B; O'Rear, J H; Earley, L; Moeller, J H; Gaffney, D K; Leavitt, D D

1997-01-01

The dose to the contralateral breast has been associated with an increased risk of developing a second breast malignancy. Varying techniques have been devised and described in the literature to minimize this dose. Metal beam modifiers such as standard wedges are used to improve the dose distribution in the treated breast, but unfortunately introduce an increased scatter dose outside the treatment field, in particular to the contralateral breast. The enhanced dynamic wedge is a means of remote wedging created by independently moving one collimator jaw through the treatment field during dose delivery. This study is an analysis of differing doses to the contralateral breast using two common clinical set-up techniques with the enhanced dynamic wedge versus the standard metal wedge. A tissue equivalent block (solid water), modeled to represent a typical breast outline, was designed as an insert in a Rando phantom to simulate a standard patient being treated for breast conservation. Tissue equivalent material was then used to complete the natural contour of the breast and to reproduce appropriate build-up and internal scatter. Thermoluminescent dosimeter (TLD) rods were placed at predetermined distances from the geometric beam's edge to measure the dose to the contralateral breast. A total of 35 locations were used with five TLDs in each location to verify the accuracy of the measured dose. The radiation techniques used were an isocentric set-up with co-planar, non divergent posterior borders and an isocentric set-up with a half beam block technique utilizing the asymmetric collimator jaw. Each technique used compensating wedges to optimize the dose distribution. A comparison of the dose to the contralateral breast was then made with the enhanced dynamic wedge vs. the standard metal wedge. The measurements revealed a significant reduction in the contralateral breast dose with the enhanced dynamic wedge compared to the standard metal wedge in both set-up techniques. The dose was measured at varying distances from the geometric field edge, ranging from 2 to 8 cm. The average dose with the enhanced dynamic wedge was 2.7-2.8%. The average dose with the standard wedge was 4.0-4.7%. Thermoluminescent dosimeter measurements suggest an increase in both scattered electrons and photons with metal wedges. The enhanced dynamic wedge is a practical clinical advance which improves the dose distribution in patients undergoing breast conservation while at the same time minimizing dose to the contralateral breast, thereby reducing the potential carcinogenic effects.

Enhanced in vivo visualization of the microcirculation by topical application of fructose solution confirmed with correlation mapping optical coherence tomography

NASA Astrophysics Data System (ADS)

Enfield, Joey; McGrath, James; Daly, Susan M.; Leahy, Martin

2016-08-01

Changes within the microcirculation can provide an early indication of the onset of a plethora of ailments. Various techniques have thus been developed that enable the study of microcirculatory irregularities. Correlation mapping optical coherence tomography (cmOCT) is a recently proposed technique, which enables mapping of vasculature networks at the capillary level in a noninvasive and noncontact manner. This technique is an extension of conventional optical coherence tomography (OCT) and is therefore likewise limited in the penetration depth of ballistic photons in biological media. Optical clearing has previously been demonstrated to enhance the penetration depth and the imaging capabilities of OCT. In order to enhance the achievable maximum imaging depth, we propose the use of optical clearing in conjunction with the cmOCT technique. We demonstrate in vivo a 13% increase in OCT penetration depth by topical application of a high-concentration fructose solution, thereby enabling the visualization of vessel features at deeper depths within the tissue.

Condensation enhancement by means of electrohydrodynamic techniques

NASA Astrophysics Data System (ADS)

Butrymowicz, Dariusz; Karwacki, Jarosław; Trela, Marian

2014-12-01

Short state-of-the-art on the enhancement of condensation heat transfer techniques by means of condensate drainage is presented in this paper. The electrohydrodynamic (EHD) technique is suitable for dielectric media used in refrigeration, organic Rankine cycles and heat pump devices. The electric field is commonly generated in the case of horizontal tubes by means of a rod-type electrode or mesh electrodes. Authors proposed two geometries in the presented own experimental investigations. The first one was an electrode placed just beneath the tube bottom and the second one consisted of a horizontal finned tube with a double electrode placed beneath the tube. The experimental investigations of these two configurations for condensation of refrigerant R-123 have been accomplished. The obtained results confirmed that the application of the EHD technique for the investigated tube and electrode arrangement caused significant increase in heat transfer coefficient. The condensation enhancement depends both on the geometry of the electrode system and on the applied voltage.

Wavelet-enhanced convolutional neural network: a new idea in a deep learning paradigm.

PubMed

Savareh, Behrouz Alizadeh; Emami, Hassan; Hajiabadi, Mohamadreza; Azimi, Seyed Majid; Ghafoori, Mahyar

2018-05-29

Manual brain tumor segmentation is a challenging task that requires the use of machine learning techniques. One of the machine learning techniques that has been given much attention is the convolutional neural network (CNN). The performance of the CNN can be enhanced by combining other data analysis tools such as wavelet transform. In this study, one of the famous implementations of CNN, a fully convolutional network (FCN), was used in brain tumor segmentation and its architecture was enhanced by wavelet transform. In this combination, a wavelet transform was used as a complementary and enhancing tool for CNN in brain tumor segmentation. Comparing the performance of basic FCN architecture against the wavelet-enhanced form revealed a remarkable superiority of enhanced architecture in brain tumor segmentation tasks. Using mathematical functions and enhancing tools such as wavelet transform and other mathematical functions can improve the performance of CNN in any image processing task such as segmentation and classification.

Results of vardenafil mediated power Doppler ultrasound, contrast enhanced ultrasound and systematic random biopsies to detect prostate cancer.

PubMed

Morelli, Girolamo; Pagni, Riccardo; Mariani, Chiara; Minervini, Riccardo; Morelli, Andrea; Gori, Francesco; Ferdeghini, Ezio Maria; Paterni, Marco; Mauro, Eva; Guidi, Elisa; Armillotta, Nicola; Canale, Domenico; Vitti, Paolo; Caramella, Davide; Minervini, Andrea

2011-06-01

We evaluated the ability of the phosphodiesterase-5 inhibitor vardenafil to increase prostate microcirculation during power Doppler ultrasound. We also evaluated the results of contrast and vardenafil enhanced targeted biopsies compared to those of standard 12-core random biopsies to detect cancer. Between May 2008 and January 2010, 150 consecutive patients with prostate specific antigen more than 4 ng/ml at first diagnosis with negative digital rectal examination and transrectal ultrasound, and no clinical history of prostatitis underwent contrast enhanced power Doppler ultrasound (bolus injection of 2.4 ml SonoVue® contrast agent), followed by vardenafil enhanced power Doppler ultrasound (1 hour after oral administration of vardenafil 20 mg). All patients underwent standard 12-core transrectal ultrasound guided random prostate biopsy plus 1 further sampling from each suspected hypervascular lesion detected by contrast and vardenafil enhanced power Doppler ultrasound. Prostate cancer was detected in 44 patients (29.3%). Contrast and vardenafil enhanced power Doppler ultrasound detected suspicious, contrast enhanced and vardenafil enhanced areas in 112 (74.6%) and 110 patients (73.3%), and was diagnostic for cancer in 32 (28.5%) and 42 (38%), respectively. Analysis of standard technique, and contrast and vardenafil enhanced power Doppler ultrasound findings by biopsy core showed significantly higher detection using vardenafil vs contrast enhanced power Doppler ultrasound and standard technique (41.2% vs 22.7% and 8.1%, p <0.005 and <0.001, respectively). The detection rate of standard plus contrast or vardenafil enhanced power Doppler ultrasound was 10% and 11.7% (p not significant). Vardenafil enhanced power Doppler ultrasound enables excellent visualization of the microvasculature associated with cancer and can improve the detection rate compared to contrast enhanced power Doppler ultrasound and the random technique. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Evaluation of lymph node perfusion using continuous mode harmonic ultrasonography with a second-generation contrast agent.

PubMed

Rubaltelli, Leopoldo; Khadivi, Yeganeh; Tregnaghi, Alberto; Stramare, Roberto; Ferro, Federica; Borsato, Simonetta; Fiocco, Ugo; Adami, Fausto; Rossi, Carlo Riccardo

2004-06-01

To evaluate the contribution of continuous mode contrast-enhanced harmonic ultrasonography (CE-HUS) with a second-generation contrast agent to the characterization of superficial lymphadenopathies with respect to conventional ultrasonographic techniques (B-mode and power Doppler). Fifty-six lymph nodes from 45 patients were studied both by conventional techniques and by CE-HUS. The dimensions, intranodal architecture, margins, and location of vessels were evaluated. Subsequently, all the lymph nodes were examined by CE-HUS, and enhancement of echogenicity was evaluated. The diagnoses obtained by means of fine-needle aspiration cytologic examination, surgical biopsy, or both were compared with those obtained by ultrasonography. Of the lymph nodes examined, 30 were benign and 26 were malignant (18 metastases and 8 non-Hodgkin lymphomas). The study using CE-HUS showed intense homogeneous enhancement in 28 of 30 reactive lymph nodes; perfusion defects in 17, of which 15 were neoplastic and 2 were inflammatory; intense but inhomogeneous speckled enhancement in the early arterial phase in 5 cases of lymphoma; and, last, scarce or absent intranodal enhancement in 4 metastases. The specificity, sensitivity, and accuracy of conventional techniques in differentiation between benign and malignant lymph nodes were 76%, 80%, and 78% versus 93%, 92%, and 92.8% for CE-HUS. The increase in correct diagnoses was significant (P = .05) when conventional ultrasonography was tested against CE-HUS. Superficial lymph nodes can be characterized as being neoplastic or benign with a high degree of diagnostic accuracy on the basis of the perfusion characteristics evaluated by CE-HUS. This technique has been shown to afford a higher degree of accuracy than currently obtainable by any other ultrasonographic technique.

Orientation-Enhanced Parallel Coordinate Plots.

PubMed

Raidou, Renata Georgia; Eisemann, Martin; Breeuwer, Marcel; Eisemann, Elmar; Vilanova, Anna

2016-01-01

Parallel Coordinate Plots (PCPs) is one of the most powerful techniques for the visualization of multivariate data. However, for large datasets, the representation suffers from clutter due to overplotting. In this case, discerning the underlying data information and selecting specific interesting patterns can become difficult. We propose a new and simple technique to improve the display of PCPs by emphasizing the underlying data structure. Our Orientation-enhanced Parallel Coordinate Plots (OPCPs) improve pattern and outlier discernibility by visually enhancing parts of each PCP polyline with respect to its slope. This enhancement also allows us to introduce a novel and efficient selection method, the Orientation-enhanced Brushing (O-Brushing). Our solution is particularly useful when multiple patterns are present or when the view on certain patterns is obstructed by noise. We present the results of our approach with several synthetic and real-world datasets. Finally, we conducted a user evaluation, which verifies the advantages of the OPCPs in terms of discernibility of information in complex data. It also confirms that O-Brushing eases the selection of data patterns in PCPs and reduces the amount of necessary user interactions compared to state-of-the-art brushing techniques.

Computer image processing - The Viking experience. [digital enhancement techniques

NASA Technical Reports Server (NTRS)

Green, W. B.

1977-01-01

Computer processing of digital imagery from the Viking mission to Mars is discussed, with attention given to subjective enhancement and quantitative processing. Contrast stretching and high-pass filtering techniques of subjective enhancement are described; algorithms developed to determine optimal stretch and filtering parameters are also mentioned. In addition, geometric transformations to rectify the distortion of shapes in the field of view and to alter the apparent viewpoint of the image are considered. Perhaps the most difficult problem in quantitative processing of Viking imagery was the production of accurate color representations of Orbiter and Lander camera images.

Use of eddy current mixes to solve a weld examination application

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

Ward, R.C.; LaBoissonniere, A.

1995-12-31

The augmentation of typical nondestructive (i.e., ultrasound) weld inspection techniques by the use of eddy current tools may significantly enhance the quality and reliability of weld inspections. One recent example is the development of an eddy current technique for use in the examination of BWR core shroud welds, where multi-frequency mixes are used to eliminate signals coming from the weld material so that the examination of the heat affected zone is enhanced. An analysis tool most commonly associated with ultrasound examinations, the C-Scan based on gated information, may be implemented with eddy current data to enhance analysis.

Preparation and Raman enhancement properties of gold nanostars

NASA Astrophysics Data System (ADS)

Shan, Feng; Zhang, Tong

2018-03-01

Gold nanostars (GNSs) have a series of sharp tips structures, which will produce strong hot spots and have great application potential in Raman enhancement. In this paper, muti-tip GNSs have been prepared experimentally, and the control techniques of their tip and size have been mastered. For the first time, a fast and efficient self-assembly technique without additives has been developed, and a series of Surface Enhanced Raman Scattering (SERS) substrates have been successfully prepared by using this technique. The effect of different GNSs density of substrates on SERS signal is further studied experimentally. The results show that the SERS signal is closely related to the density of particles in the substrate. The higher density of GNSs in the substrate, the more hot spots covered by the incident light plate, and the greater contribution to the SERS signal.

Enhanced Indirect Somatic Embryogenesis of Date Palm Using Low Levels of Seawater.

PubMed

Taha, Rania A

2017-01-01

Date palm tolerates salinity, drought, and high temperatures. Arid and semiarid zones, especially the Middle East region, need a huge number of date palms for cultivation. To meet this demand, tissue culture techniques have great potential for mass production of plantlets, especially using the indirect embryogenesis technique; any improvement of these techniques is a worthy objective. Low levels of salinity can enhance growth and development of tolerant plants. A low level of seawater, a natural source of salinity, reduces the time required for micropropagation processes of date palm cv. Malkaby when added to MS medium. Medium containing seawater at 500 ppm total dissolved solid (TDS) (12.2 mL/L) improves callus proliferation, whereas 1500 ppm (36.59 mL/L) enhances plant regeneration including multiplication of secondary embryos, embryo germination, and rooting.

Enhanced sampling techniques in biomolecular simulations.

PubMed

Spiwok, Vojtech; Sucur, Zoran; Hosek, Petr

2015-11-01

Biomolecular simulations are routinely used in biochemistry and molecular biology research; however, they often fail to match expectations of their impact on pharmaceutical and biotech industry. This is caused by the fact that a vast amount of computer time is required to simulate short episodes from the life of biomolecules. Several approaches have been developed to overcome this obstacle, including application of massively parallel and special purpose computers or non-conventional hardware. Methodological approaches are represented by coarse-grained models and enhanced sampling techniques. These techniques can show how the studied system behaves in long time-scales on the basis of relatively short simulations. This review presents an overview of new simulation approaches, the theory behind enhanced sampling methods and success stories of their applications with a direct impact on biotechnology or drug design. Copyright © 2014 Elsevier Inc. All rights reserved.

Towards optical brain imaging: getting light through a bone

NASA Astrophysics Data System (ADS)

Thompson, J. V.; Hokr, B. H.; Nodurft, D. T.; Yakovlev, V. V.

2018-06-01

Optical imaging and detection in biological samples is severely limited by scattering effects. In particular, optical techniques for measuring conditions beneath the skull and within the bone marrow hold significant promise when it comes to speed, sensitivity and specificity. However, the strong optical scattering due to bone hinders the realization of these methods. In this article, we propose a technique to enhance the transmittance of light through bone. This is achieved by injecting light below the top surface of the bone and utilizing multiple scattering to increase transmittance. This technique suggests that enhancements of 2-6 times may be realized by injection of light 1 mm below the surface of the bone. By enhancing the transmittance of light through bone, we will greatly improve our ability to utilize optical methods to better understand and diagnose conditions within biological media.

Implementation of spatial overlap modulation nonlinear optical microscopy using an electro-optic deflector

PubMed Central

Isobe, Keisuke; Kawano, Hiroyuki; Kumagai, Akiko; Miyawaki, Atsushi; Midorikawa, Katsumi

2013-01-01

A spatial overlap modulation (SPOM) technique is a nonlinear optical microscopy technique which enhances the three-dimensional spatial resolution and rejects the out-of-focus background limiting the imaging depth inside a highly scattering sample. Here, we report on the implementation of SPOM in which beam pointing modulation is achieved by an electro-optic deflector. The modulation and demodulation frequencies are enhanced to 200 kHz and 400 kHz, respectively, resulting in a 200-fold enhancement compared with the previously reported system. The resolution enhancement and suppression of the out-of-focus background are demonstrated by sum-frequency-generation imaging of pounded granulated sugar and deep imaging of fluorescent beads in a tissue-like phantom, respectively. PMID:24156055

Note: A novel technique for analysis of aqueous solutions by laser-induced breakdown spectroscopy

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

Rusak, D. A.; Bell, Z. T.; Anthony, T. P.

2015-11-15

Surface-enhanced Raman spectroscopy (SERS) substrates typically consist of gold or silver nanoparticles deposited on a non-conductive substrate. In Raman spectroscopy, the nanoparticles produce an enhancement of the electromagnetic field which, in turn, leads to greater electronic excitation of molecules in the local environment. Here, we show that these same surfaces can be used to enhance the signal-to-noise ratio obtained in laser-induced breakdown spectroscopy of aqueous solutions. In this case, the SERS substrates not only lower breakdown thresholds and lead to more efficient plasma initiation but also provide an appropriately wettable surface for the deposition of the liquid. We refer tomore » this technique as surface-enhanced laser-induced breakdown spectroscopy.« less

Real-time multiplexed digital cavity-enhanced spectroscopy

DOE PAGES

Boyson, Toby K.; Dagdigian, Paul J.; Pavey, Karl D.; ...

2015-10-01

Cavity-enhanced spectroscopy is a sensitive optical absorption technique but one where the practical applications have been limited to studying small wavelength ranges. In addition, this Letter shows that wideband operation can be achieved by combining techniques usually reserved for the communications community with that of cavity-enhanced spectroscopy, producing a multiplexed real-time cavity-enhanced spectrometer. We use multiple collinear laser sources operating asynchronously and simultaneously while being detected on a single photodetector. This is synonymous with radio frequency (RF) cellular systems in which signals are detected on a single antenna but decoded uniquely. Here, we demonstrate results with spectra of methyl salicylatemore » and show parts-per-billion per root hertz sensitivity measured in real-time.« less

Tip-Enhanced Raman Scattering Microscopy: A Step toward Nanoscale Control of Intrinsic Molecular Properties

NASA Astrophysics Data System (ADS)

Yano, Taka-aki; Hara, Masahiko

2018-06-01

Tip-enhanced Raman scattering microscopy, a family of scanning probe microscopy techniques, has been recognized as a powerful surface analytical technique with both single-molecule sensitivity and angstrom-scale spatial resolution. This review covers the current status of tip-enhanced Raman scattering microscopy in surface and material nanosciences, including a brief history, the basic principles, and applications for the nanoscale characterization of a variety of nanomaterials. The focus is on the recent trend of combining tip-enhanced Raman scattering microscopy with various external stimuli such as pressure, voltage, light, and temperature, which enables the local control of the molecular properties and functions and also enables chemical reactions to be induced on a nanometer scale.

On-the-Fly Control of High-Harmonic Generation Using a Structured Pump Beam

NASA Astrophysics Data System (ADS)

Hareli, Liran; Lobachinsky, Lilya; Shoulga, Georgiy; Eliezer, Yaniv; Michaeli, Linor; Bahabad, Alon

2018-05-01

We demonstrate experimentally a relatively simple yet powerful all-optical enhancement and control technique for high harmonic generation. This is achieved by using as a pump beam two different spatial optical modes interfering together to realize tunable periodic quasi-phase matching of the interaction. With this technique, we demonstrate on-the-fly quasi-phase matching of harmonic orders 29-41 at ambient gas pressure levels of 50 and 100 Torr, where an up to 100-fold enhancement of the emission is observed. The technique is scalable to different harmonic orders and ambient pressure conditions.

On-the-Fly Control of High-Harmonic Generation Using a Structured Pump Beam.

PubMed

Hareli, Liran; Lobachinsky, Lilya; Shoulga, Georgiy; Eliezer, Yaniv; Michaeli, Linor; Bahabad, Alon

2018-05-04

We demonstrate experimentally a relatively simple yet powerful all-optical enhancement and control technique for high harmonic generation. This is achieved by using as a pump beam two different spatial optical modes interfering together to realize tunable periodic quasi-phase matching of the interaction. With this technique, we demonstrate on-the-fly quasi-phase matching of harmonic orders 29-41 at ambient gas pressure levels of 50 and 100 Torr, where an up to 100-fold enhancement of the emission is observed. The technique is scalable to different harmonic orders and ambient pressure conditions.

Pump-probe differencing technique for cavity-enhanced, noise-canceling saturation laser spectroscopy.

PubMed

de Vine, Glenn; McClelland, David E; Gray, Malcolm B; Close, John D

2005-05-15

We present an experimental technique that permits mechanical-noise-free, cavity-enhanced frequency measurements of an atomic transition and its hyperfine structure. We employ the 532-nm frequency-doubled output from a Nd:YAG laser and an iodine vapor cell. The cell is placed in a folded ring cavity (FRC) with counterpropagating pump and probe beams. The FRC is locked with the Pound-Drever-Hall technique. Mechanical noise is rejected by differencing the pump and probe signals. In addition, this differenced error signal provides a sensitive measure of differential nonlinearity within the FRC.

Wide-field in vivo neocortical calcium dye imaging using a convection-enhanced loading technique combined with simultaneous multiwavelength imaging of voltage-sensitive dyes and hemodynamic signals

PubMed Central

Ma, Hongtao; Harris, Samuel; Rahmani, Redi; Lacefield, Clay O.; Zhao, Mingrui; Daniel, Andy G. S.; Zhou, Zhiping; Bruno, Randy M.; Berwick, Jason; Schwartz, Theodore H.

2014-01-01

Abstract. In vivo calcium imaging is an incredibly powerful technique that provides simultaneous information on fast neuronal events, such as action potentials and subthreshold synaptic activity, as well as slower events that occur in the glia and surrounding neuropil. Bulk-loading methods that involve multiple injections can be used for single-cell as well as wide-field imaging studies. However, multiple injections result in inhomogeneous loading as well as multiple sites of potential cortical injury. We used convection-enhanced delivery to create smooth, continuous loading of a large area of the cortical surface through a solitary injection site and demonstrated the efficacy of the technique using confocal microscopy imaging of single cells and physiological responses to single-trial events of spontaneous activity, somatosensory-evoked potentials, and epileptiform events. Combinations of calcium imaging with voltage-sensitive dye and intrinsic signal imaging demonstrate the utility of this technique in neurovascular coupling investigations. Convection-enhanced loading of calcium dyes may be a useful technique to advance the study of cortical processing when widespread loading of a wide-field imaging is required. PMID:25525611

Wide-field in vivo neocortical calcium dye imaging using a convection-enhanced loading technique combined with simultaneous multiwavelength imaging of voltage-sensitive dyes and hemodynamic signals.

PubMed

Ma, Hongtao; Harris, Samuel; Rahmani, Redi; Lacefield, Clay O; Zhao, Mingrui; Daniel, Andy G S; Zhou, Zhiping; Bruno, Randy M; Berwick, Jason; Schwartz, Theodore H

2014-07-24

In vivo calcium imaging is an incredibly powerful technique that provides simultaneous information on fast neuronal events, such as action potentials and subthreshold synaptic activity, as well as slower events that occur in the glia and surrounding neuropil. Bulk-loading methods that involve multiple injections can be used for single-cell as well as wide-field imaging studies. However, multiple injections result in inhomogeneous loading as well as multiple sites of potential cortical injury. We used convection-enhanced delivery to create smooth, continuous loading of a large area of the cortical surface through a solitary injection site and demonstrated the efficacy of the technique using confocal microscopy imaging of single cells and physiological responses to single-trial events of spontaneous activity, somatosensory-evoked potentials, and epileptiform events. Combinations of calcium imaging with voltage-sensitive dye and intrinsic signal imaging demonstrate the utility of this technique in neurovascular coupling investigations. Convection-enhanced loading of calcium dyes may be a useful technique to advance the study of cortical processing when widespread loading of a wide-field imaging is required.

The effects of solar incidence angle over digital processing of LANDSAT data

NASA Technical Reports Server (NTRS)

Parada, N. D. J. (Principal Investigator); Novo, E. M. L. M.

1983-01-01

A technique to extract the topography modulation component from digital data is described. The enhancement process is based on the fact that the pixel contains two types of information: (1) reflectance variation due to the target; (2) reflectance variation due to the topography. In order to enhance the signal variation due to topography, the technique recommends the extraction from original LANDSAT data of the component resulting from target reflectance. Considering that the role of topographic modulation over the pixel information will vary with solar incidence angle, the results of this technique of digital processing will differ from one season to another, mainly in highly dissected topography. In this context, the effects of solar incidence angle over the topographic modulation technique were evaluated. Two sets of MSS/LANDSAT data, with solar elevation angles varying from 22 to 41 deg were selected to implement the digital processing at the Image-100 System. A secondary watershed (Rio Bocaina) draining into Rio Paraiba do Sul (Sao Paulo State) was selected as a test site. The results showed that the technique used was more appropriate to MSS data acquired under higher Sun elevation angles. Topographic modulation components applied to low Sun elevation angles lessens rather than enhances topography.

[Rapid measurement of trace mercury in aqueous solutions with optical-electrical dual pulse LIBS technique].

PubMed

Zhang, Qian; Xiong, Wei; Chen, Yu-Qi; Li, Run-Hua

2011-02-01

A wood slice was used as absorber to transfer liquid sample to solid sample in order to solve the problems existing in directly analyzing aqueous solutions with laser-induced breakdown spectroscopy (LIBS). An optical-electrical dual pulse LIBS (OEDP-LIBS) technique was first used to enhance atomic emission of mercury in laser-induced plasma. The calibration curves of mercury were obtained by typical single pulse LIBS and OEDP-LIBS techniques. The limit of detection (LOD) of mercury in these two techniques reaches 2.4 and 0.3 mg x L(-1), respectively. Under current experimental conditions, the time-integrated a tomic emission of mercury at 253.65 nm was enhanced 50 times and the LOD of mercury was improved by one order, if comparing OEDP-LIBS to single pulse LIBS. The required time for a whole analysis process is less than 5 minutes. As the atomic emission of mercury decays slowly while increasing the delay time between electrical pulse and laser pulse, increasing the electrical pulse width can further enhance the time integrated intensity of mercury emission and improve the detection sensitivity of mercury by OEDP-LIBS technique.

Perfluorocarbons enhance a T2*-based MRI technique for identifying the penumbra in a rat model of acute ischemic stroke

PubMed Central

Deuchar, Graeme A; Brennan, David; Griffiths, Hugh; Macrae, I  Mhairi; Santosh, Celestine

2013-01-01

Accurate imaging of ischemic penumbra is crucial for improving the management of acute stroke patients. T2* magnetic resonance imaging (MRI) combined with a T2*oxygen challenge (T2*OC) is being developed to detect penumbra based on changes in blood deoxyhemoglobin. Using 100% O2, T2*OC-defined penumbra exhibits ongoing glucose metabolism and tissue recovery on reperfusion. However, potential limitations in translating this technique include a sinus artefact in human scans with delivery of 100% OC and relatively small signal changes. Here we investigate whether an oxygen-carrying perfluorocarbon (PFC) emulsion can enhance the sensitivity of the technique, enabling penumbra detection with lower levels of inspired oxygen. Stroke was induced in male Sprague-Dawley rats (n=17) with ischemic injury and perfusion deficit determined by diffusion and perfusion MRI, respectively. T2* signal change was measured in regions of interest (ROIs) located within ischemic core, T2*OC-defined penumbra and equivalent contralateral areas during 40% O2±prior PFC injection. Region of interest analyses between groups showed that PFC significantly enhanced the T2* response to 40% O2 in T2*-defined penumbra (mean increase of 10.6±2.3% compared to 5.6±1.5% with 40% O2, P<0.001). This enhancement was specific to the penumbra ROI. Perfluorocarbon emulsions therefore enhances the translational potential of the T2*OC technique for identifying penumbra in acute stroke patients. PMID:23801243

Experimental validation of energy parameters in parabolic trough collector with plain absorber and analysis of heat transfer enhancement techniques

NASA Astrophysics Data System (ADS)

Bilal, F. R.; Arunachala, U. C.; Sandeep, H. M.

2018-01-01

The quantum of heat loss from the receiver of the Parabolic Trough Collector is considerable which results in lower thermal efficiency of the system. Hence heat transfer augmentation is essential which can be attained by various techniques. An analytical model to evaluate the system with bare receiver performance was developed using MATLAB. The experimental validation of the model resulted in less than 5.5% error in exit temperature using both water and thermic oil as heat transfer fluid. Further, heat transfer enhancement techniques were incorporated in the model which included the use of twisted tape inserts, nanofluid, and a combination of both for further enhancement. It was observed that the use of evacuated glass cover in the existing setup would increase the useful heat gain up to 5.3%. Fe3O4/H2O nanofluid showed a maximum enhancement of 56% in the Nusselt number for the volume concentration of 0.6% at highest Reynolds number. Similarly, twisted tape turbulators (with twist ratio of 2) taken alone with water exhibited 59% improvement in Nusselt number. Combining both the heat transfer augmentation techniques at their best values revealed the Nusselt number enhancement up to 87%. It is concluded that, use of twisted tape with water is the best method for heat transfer augmentation since it gives the maximum effective thermal efficiency amongst all for the range of Re considered. The first section in your paper

Spectral Analysis and Experimental Modeling of Ice Accretion Roughness

NASA Technical Reports Server (NTRS)

Orr, D. J.; Breuer, K. S.; Torres, B. E.; Hansman, R. J., Jr.

1996-01-01

A self-consistent scheme for relating wind tunnel ice accretion roughness to the resulting enhancement of heat transfer is described. First, a spectral technique of quantitative analysis of early ice roughness images is reviewed. The image processing scheme uses a spectral estimation technique (SET) which extracts physically descriptive parameters by comparing scan lines from the experimentally-obtained accretion images to a prescribed test function. Analysis using this technique for both streamwise and spanwise directions of data from the NASA Lewis Icing Research Tunnel (IRT) are presented. An experimental technique is then presented for constructing physical roughness models suitable for wind tunnel testing that match the SET parameters extracted from the IRT images. The icing castings and modeled roughness are tested for enhancement of boundary layer heat transfer using infrared techniques in a "dry" wind tunnel.

Nano-Optics for Chemical and Materials Characterization

NASA Astrophysics Data System (ADS)

Beversluis, Michael; Stranick, Stephan

2007-03-01

Light microscopy can provide non-destructive, real-time, three-dimensional imaging with chemically-specific contrast, but diffraction frequently limits the resolution to roughly 200 nm. Recently, structured illumination techniques have allowed fluorescence imaging to reach 50 nm resolution [1]. Since these fluorescence techniques were developed for use in microbiology, a key challenge is to take the resolution-enhancing features and apply them to contrast mechanisms like vibrational spectroscopy (e.g., Raman and CARS microscopy) that provide morphological and chemically specific imaging.. We are developing a new hybrid technique that combines the resolution enhancement of structured illumination microscopy with scanning techniques that can record hyperspectral images with 100 nm spatial resolution. We will show such superresolving images of semiconductor nanostructures and discuss the advantages and requirements for this technique. Referenence: 1. M. G. L. Gustafsson, P. Natl. Acad. Sci. USA 102, 13081-13086 (2005).

Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications

PubMed Central

Ohno, Yoshiharu; Koyama, Hisanobu; Lee, Ho Yun; Miura, Sachiko; Yoshikawa, Takeshi; Sugimura, Kazuro

2016-01-01

Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases. PMID:27523813

Image contrast enhancement using adjacent-blocks-based modification for local histogram equalization

NASA Astrophysics Data System (ADS)

Wang, Yang; Pan, Zhibin

2017-11-01

Infrared images usually have some non-ideal characteristics such as weak target-to-background contrast and strong noise. Because of these characteristics, it is necessary to apply the contrast enhancement algorithm to improve the visual quality of infrared images. Histogram equalization (HE) algorithm is a widely used contrast enhancement algorithm due to its effectiveness and simple implementation. But a drawback of HE algorithm is that the local contrast of an image cannot be equally enhanced. Local histogram equalization algorithms are proved to be the effective techniques for local image contrast enhancement. However, over-enhancement of noise and artifacts can be easily found in the local histogram equalization enhanced images. In this paper, a new contrast enhancement technique based on local histogram equalization algorithm is proposed to overcome the drawbacks mentioned above. The input images are segmented into three kinds of overlapped sub-blocks using the gradients of them. To overcome the over-enhancement effect, the histograms of these sub-blocks are then modified by adjacent sub-blocks. We pay more attention to improve the contrast of detail information while the brightness of the flat region in these sub-blocks is well preserved. It will be shown that the proposed algorithm outperforms other related algorithms by enhancing the local contrast without introducing over-enhancement effects and additional noise.

Therapeutic enhancement: nursing intervention category for patients diagnosed with Readiness for Therapeutic Regimen Management.

PubMed

Kelly, Cynthia W

2008-04-01

To present a new nursing intervention category called therapeutic enhancement. Fewer than half of North Americans follow their physician's recommendations for diet and exercise, even when such are crucial to their health or recovery. It is imperative that nurses consider new ways to promote healthy behaviours. Therapeutic enhancement is intended to provide such a fresh approach. Traditional intervention techniques focusing on education, contracts, social support and more frequent interaction with physicians appear not to be effective when used alone. Successful strategies have been multidisciplinary; and have included interventions by professional nurses who assist patients to understand their disease and the disease process and that helps them to develop disease-management and self-management skills. Therapeutic enhancement incorporates The Stages of Change Theory, Commitment to Health Theory, Motivational Interviewing techniques and instrumentation specifically designed for process evaluation of health-promoting interventions. This is a critical review of approaches that, heretofore, have not been synthesised in a single published article. Based on the commonly used Stages of Change model, therapeutic enhancement is useful for patients who are at the action stage of change. Using therapeutic enhancement as well as therapeutic strategies identified in Stages of Change Theory, such as contingency management, helping relationships, counterconditioning, stimulus control and Motivational Interviewing techniques, nursing professionals can significantly increase the chances of patients moving from action to the maintenance stage of change for a specific health behaviour. Using the nursing intervention category, therapeutic enhancement can increase caregivers' success in helping patients maintain healthy behaviours.

The Random-Map Technique: Enhancing Mind-Mapping with a Conceptual Combination Technique to Foster Creative Potential

ERIC Educational Resources Information Center

Malycha, Charlotte P.; Maier, Günter W.

2017-01-01

Although creativity techniques are highly recommended in working environments, their effects have been scarcely investigated. Two cognitive processes are often considered to foster creative potential and are, therefore, taken as a basis for creativity techniques: knowledge activation and conceptual combination. In this study, both processes were…

Image enhancement using MCNP5 code and MATLAB in neutron radiography.

PubMed

Tharwat, Montaser; Mohamed, Nader; Mongy, T

2014-07-01

This work presents a method that can be used to enhance the neutron radiography (NR) image for objects with high scattering materials like hydrogen, carbon and other light materials. This method used Monte Carlo code, MCNP5, to simulate the NR process and get the flux distribution for each pixel of the image and determines the scattered neutron distribution that caused image blur, and then uses MATLAB to subtract this scattered neutron distribution from the initial image to improve its quality. This work was performed before the commissioning of digital NR system in Jan. 2013. The MATLAB enhancement method is quite a good technique in the case of static based film neutron radiography, while in neutron imaging (NI) technique, image enhancement and quantitative measurement were efficient by using ImageJ software. The enhanced image quality and quantitative measurements were presented in this work. Copyright © 2014 Elsevier Ltd. All rights reserved.

Perfluorocarbon Enhanced Glasgow Oxygen Level Dependent (GOLD) Magnetic Resonance Metabolic Imaging Identifies the Penumbra Following Acute Ischemic Stroke

PubMed Central

Deuchar, Graeme A; Brennan, David; Holmes, William M; Shaw, Martin; Macrae, I Mhairi; Santosh, Celestine

2018-01-01

The ability to identify metabolically active and potentially salvageable ischaemic penumbra is crucial for improving treatment decisions in acute stroke patients. Our solution involves two complementary novel MRI techniques (Glasgow Oxygen Level Dependant (GOLD) Metabolic Imaging), which when combined with a perfluorocarbon (PFC) based oxygen carrier and hyperoxia can identify penumbra due to dynamic changes related to continued metabolism within this tissue compartment. Our aims were (i) to investigate whether PFC offers similar enhancement of the second technique (Lactate Change) as previously demonstrated for the T2*OC technique (ii) to demonstrate both GOLD metabolic imaging techniques working concurrently to identify penumbra, following administration of Oxycyte® (O-PFC) with hyperoxia. Methods: An established rat stroke model was utilised. Part-1: Following either saline or PFC, magnetic resonance spectroscopy was applied to investigate the effect of hyperoxia on lactate change in presumed penumbra. Part-2; rats received O-PFC prior to T2*OC (technique 1) and MR spectroscopic imaging, which was used to identify regions of tissue lactate change (technique 2) in response to hyperoxia. In order to validate the techniques, imaging was followed by [14C]2-deoxyglucose autoradiography to correlate tissue metabolic status to areas identified as penumbra. Results: Part-1: PFC+hyperoxia resulted in an enhanced reduction of lactate in the penumbra when compared to saline+hyperoxia. Part-2: Regions of brain tissue identified as potential penumbra by both GOLD metabolic imaging techniques utilising O-PFC, demonstrated maintained glucose metabolism as compared to adjacent core tissue. Conclusion: For the first time in vivo, enhancement of both GOLD metabolic imaging techniques has been demonstrated following intravenous O-PFC+hyperoxia to identify ischaemic penumbra. We have also presented preliminary evidence of the potential therapeutic benefit offered by O-PFC. These unique theranostic applications would enable treatment based on metabolic status of the brain tissue, independent of time from stroke onset, leading to increased uptake and safer use of currently available treatment options. PMID:29556351

Contrast enhancement of bite mark images using the grayscale mixer in ACR in Photoshop®.

PubMed

Evans, Sam; Noorbhai, Suzanne; Lawson, Zoe; Stacey-Jones, Seren; Carabott, Romina

2013-05-01

Enhanced images may improve bite mark edge definition, assisting forensic analysis. Current contrast enhancement involves color extraction, viewing layered images by channel. A novel technique, producing a single enhanced image using the grayscale mix panel within Adobe Camera Raw®, has been developed and assessed here, allowing adjustments of multiple color channels simultaneously. Stage 1 measured RGB values in 72 versions of a color chart image; eight sliders in Photoshop® were adjusted at 25% intervals, all corresponding colors affected. Stage 2 used a bite mark image, and found only red, orange, and yellow sliders had discernable effects. Stage 3 assessed modality preference between color, grayscale, and enhanced images; on average, the 22 survey participants chose the enhanced image as better defined for nine out of 10 bite marks. The study has shown potential benefits for this new technique. However, further research is needed before use in the analysis of bite marks. © 2013 American Academy of Forensic Sciences.

Breath Analysis Using Laser Spectroscopic Techniques: Breath Biomarkers, Spectral Fingerprints, and Detection Limits

PubMed Central

Wang, Chuji; Sahay, Peeyush

2009-01-01

Breath analysis, a promising new field of medicine and medical instrumentation, potentially offers noninvasive, real-time, and point-of-care (POC) disease diagnostics and metabolic status monitoring. Numerous breath biomarkers have been detected and quantified so far by using the GC-MS technique. Recent advances in laser spectroscopic techniques and laser sources have driven breath analysis to new heights, moving from laboratory research to commercial reality. Laser spectroscopic detection techniques not only have high-sensitivity and high-selectivity, as equivalently offered by the MS-based techniques, but also have the advantageous features of near real-time response, low instrument costs, and POC function. Of the approximately 35 established breath biomarkers, such as acetone, ammonia, carbon dioxide, ethane, methane, and nitric oxide, 14 species in exhaled human breath have been analyzed by high-sensitivity laser spectroscopic techniques, namely, tunable diode laser absorption spectroscopy (TDLAS), cavity ringdown spectroscopy (CRDS), integrated cavity output spectroscopy (ICOS), cavity enhanced absorption spectroscopy (CEAS), cavity leak-out spectroscopy (CALOS), photoacoustic spectroscopy (PAS), quartz-enhanced photoacoustic spectroscopy (QEPAS), and optical frequency comb cavity-enhanced absorption spectroscopy (OFC-CEAS). Spectral fingerprints of the measured biomarkers span from the UV to the mid-IR spectral regions and the detection limits achieved by the laser techniques range from parts per million to parts per billion levels. Sensors using the laser spectroscopic techniques for a few breath biomarkers, e.g., carbon dioxide, nitric oxide, etc. are commercially available. This review presents an update on the latest developments in laser-based breath analysis. PMID:22408503

A Geophysical Inversion Model Enhancement Technique Based on the Blind Deconvolution

NASA Astrophysics Data System (ADS)

Zuo, B.; Hu, X.; Li, H.

2011-12-01

A model-enhancement technique is proposed to enhance the geophysical inversion model edges and details without introducing any additional information. Firstly, the theoretic correctness of the proposed geophysical inversion model-enhancement technique is discussed. An inversion MRM (model resolution matrix) convolution approximating PSF (Point Spread Function) method is designed to demonstrate the correctness of the deconvolution model enhancement method. Then, a total-variation regularization blind deconvolution geophysical inversion model-enhancement algorithm is proposed. In previous research, Oldenburg et al. demonstrate the connection between the PSF and the geophysical inverse solution. Alumbaugh et al. propose that more information could be provided by the PSF if we return to the idea of it behaving as an averaging or low pass filter. We consider the PSF as a low pass filter to enhance the inversion model basis on the theory of the PSF convolution approximation. Both the 1D linear and the 2D magnetotelluric inversion examples are used to analyze the validity of the theory and the algorithm. To prove the proposed PSF convolution approximation theory, the 1D linear inversion problem is considered. It shows the ratio of convolution approximation error is only 0.15%. The 2D synthetic model enhancement experiment is presented. After the deconvolution enhancement, the edges of the conductive prism and the resistive host become sharper, and the enhancement result is closer to the actual model than the original inversion model according the numerical statistic analysis. Moreover, the artifacts in the inversion model are suppressed. The overall precision of model increases 75%. All of the experiments show that the structure details and the numerical precision of inversion model are significantly improved, especially in the anomalous region. The correlation coefficient between the enhanced inversion model and the actual model are shown in Fig. 1. The figure illustrates that more information and details structure of the actual model are enhanced through the proposed enhancement algorithm. Using the proposed enhancement method can help us gain a clearer insight into the results of the inversions and help make better informed decisions.

The Use of Confocal Photoluminescence Microscopy for Determination of Defect Densities in Various 2-6 Semiconductors

DTIC Science & Technology

2014-03-11

optical configuration that significantly enhances both lateral and depth resolution and returns crisp PL images 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND...that significantly enhances both lateral and depth resolution and returns crisp PL images with high contrast. This technique revolutionized fluorescent...resolution and returns crisp PL images with high contrast. This technique revolutionized fluorescent imaging in biology, and has the potential to

Enhanced weak-signal sensitivity in two-photon microscopy by adaptive illumination.

PubMed

Chu, Kengyeh K; Lim, Daryl; Mertz, Jerome

2007-10-01

We describe a technique to enhance both the weak-signal relative sensitivity and the dynamic range of a laser scanning optical microscope. The technique is based on maintaining a fixed detection power by fast feedback control of the illumination power, thereby transferring high measurement resolution to weak signals while virtually eliminating the possibility of image saturation. We analyze and demonstrate the benefits of adaptive illumination in two-photon fluorescence microscopy.

Research to support sterile-male-release and genetic alteration techniques for sea lamprey control

USGS Publications Warehouse

Bergstedt, Roger A.; Twohey, Michael B.

2007-01-01

Integrated pest management of sea lampreys in the Laurentian Great Lakes has recently been enhanced by addition of a sterile-male-release program, and future developments in genetic approaches may lead to additional methods for reducing sea lamprey reproduction. We review the development, implementation, and evaluation of the sterile-male-release technique (SMRT) as it is being applied against sea lampreys in the Great Lakes, review the current understanding of SMRT efficacy, and identify additional research areas and topics that would increase either the efficacy of the SMRT or expand its geographic potential for application. Key areas for additional research are in the sterilization process, effects of skewed sex ratios on mating behavior, enhancing attractiveness of sterilized males, techniques for genetic alteration of sea lampreys, and sources of animals to enhance or expand the use of sterile lampreys.

Image smoothing and enhancement via min/max curvature flow

NASA Astrophysics Data System (ADS)

Malladi, Ravikanth; Sethian, James A.

1996-03-01

We present a class of PDE-based algorithms suitable for a wide range of image processing applications. The techniques are applicable to both salt-and-pepper gray-scale noise and full- image continuous noise present in black and white images, gray-scale images, texture images and color images. At the core, the techniques rely on a level set formulation of evolving curves and surfaces and the viscosity in profile evolution. Essentially, the method consists of moving the isointensity contours in an image under curvature dependent speed laws to achieve enhancement. Compared to existing techniques, our approach has several distinct advantages. First, it contains only one enhancement parameter, which in most cases is automatically chosen. Second, the scheme automatically stops smoothing at some optimal point; continued application of the scheme produces no further change. Third, the method is one of the fastest possible schemes based on a curvature-controlled approach.

APPLICATION OF VARIOUS POLYMERS AND POLYMERS BASED TECHNIQUES USED TO IMPROVE SOLUBILITY OF POORLY WATER SOLUBLE DRUGS: A REVIEW.

PubMed

Muhammad Sarfraz, Rai; Bashir, Sajid; Mahmood, Asif; Ahsan, Haseeb; Riaz, Humayun; Raza, Hina; Rashid, Zermina; Atif Raza, Syed; Asad Abrar, Muhammad; Abbas, Khawar; Yasmeen, Tahira

2017-03-01

Solubility is concerned with solute and solvent to form a homogenous mixture. If solubility of a drug is low, then usually it is difficult to achieve desired therapeutic level of drug. Most of the newly developed entities have solubility problems and encounter difficulty in dissolution. Basic aim of solubility enhancement is to achieve desired therapeutic'level of drug to produce required pharmacological response. Different techniques are being used to enhance the solubility of water insoluble drugs. These techniques include particle size reduction, spray drying, kneading method, solvent evaporation method, salt formation, microemulsions, co-solven- cy, hydrosols, prodrug approach, supercritical fluid process, hydrogel micro particles etc. Selection of solubility improving method depends on drug properties, site of absorption, and required dosage form characteristics. Variety of polymers are also used to enhance solubility of these drugs like polyethylene glycol 300, polyvinyl pyrrolidone, chitosan, β-cyclodextrins etc.

Time-resolved two-window measurement of Wigner functions for coherent backscatter from a turbid medium

NASA Astrophysics Data System (ADS)

Reil, Frank; Thomas, John E.

2002-05-01

For the first time we are able to observe the time-resolved Wigner function of enhanced backscatter from a random medium using a novel two-window technique. This technique enables us to directly verify the phase-conjugating properties of random media. An incident divergent beam displays a convergent enhanced backscatter cone. We measure the joint position and momentum (x, p) distributions of the light field as a function of propagation time in the medium. The two-window technique allows us to independently control the resolutions for position and momentum, thereby surpassing the uncertainty limit associated with Fourier transform pairs. By using a low-coherence light source in a heterodyne detection scheme, we observe enhanced backscattering resolved by path length in the random medium, providing information about the evolution of optical coherence as a function of penetration depth in the random medium.

Osteopathic lymphatic pump techniques to enhance immunity and treat pneumonia.

PubMed

Hodge, Lisa M

2012-03-01

Pneumonia is a common cause of morbidity and mortality worldwide. While antibiotics are generally effective for the treatment of infection, the emergence of resistant strains of bacteria threatens their success. The osteopathic medical profession has designed a set of manipulative techniques called lymphatic pump techniques (LPT), to enhance the flow of lymph through the lymphatic system. Clinically, LPT is used to treat infection and oedemaand might be an effective adjuvant therapy in patients with pneumonia.The immune system uses the lymphatic and blood systems to survey to rid the body of pathogens; however, only recently have the effects of LPT on the lymphatic and immune systems been investigated. This short review highlightsclinical and basic science research studies that support the use of LPT to enhance the lymphatic and immune systems and treat pneumonia, and discusses the potential mechanisms by which LPT benefits patients with pneumonia.

Teaching communication skills: using action methods to enhance role-play in problem-based learning.

PubMed

Baile, Walter F; Blatner, Adam

2014-08-01

Role-play is a method of simulation used commonly to teach communication skills. Role-play methods can be enhanced by techniques that are not widely used in medical teaching, including warm-ups, role-creation, doubling, and role reversal. The purposes of these techniques are to prepare learners to take on the role of others in a role-play; to develop an insight into unspoken attitudes, thoughts, and feelings, which often determine the behavior of others; and to enhance communication skills through the participation of learners in enactments of communication challenges generated by them. In this article, we describe a hypothetical teaching session in which an instructor applies each of these techniques in teaching medical students how to break bad news using a method called SPIKES [Setting, Perception, Invitation, Knowledge, Emotions, Strategy, and Summary]. We illustrate how these techniques track contemporary adult learning theory through a learner-centered, case-based, experiential approach to selecting challenging scenarios in giving bad news, by attending to underlying emotion and by using reflection to anchor new learning.

Pressurized capillary electrochromatographic analysis of water-soluble vitamins by combining with on-line concentration technique.

PubMed

Jia, Li; Liu, Yaling; Du, Yanyan; Xing, Da

2007-06-22

A pressurized capillary electrochromatography (pCEC) system was developed for the separation of water-soluble vitamins, in which UV absorbance was used as the detection method and a monolithic silica-ODS column as the separation column. The parameters (type and content of organic solvent in the mobile phase, type and concentration of electrolyte, pH of the electrolyte buffer, applied voltage and flow rate) affecting the separation resolution were evaluated. The combination of two on-line concentration techniques, namely, solvent gradient zone sharpening effect and field-enhanced sample stacking, was utilized to improve detection sensitivity, which proved to be beneficial to enhance the detection sensitivity by enabling the injection of large volumes of samples. Coupling electrokinetic injection with the on-line concentration techniques was much more beneficial for the concentration of positively charged vitamins. Comparing with the conventional injection mode, the enhancement in the detection sensitivities of water-soluble vitamins using the on-line concentration technique is in the range of 3 to 35-fold. The developed pCEC method was applied to evaluate water-soluble vitamins in corns.

Exploiting Sub-threshold and above-threshold characteristics in a silver-enhanced gold nanoparticle based biochip.

PubMed

Liu, Yang; Alocilja, Evangelyn; Chakrabartty, Shantanu

2009-01-01

Silver-enhanced labeling is a technique used in immunochromatographic assays for improving the sensitivity of pathogen detection. In this paper, we employ the silver enhancement approach for constructing a biomolecular transistor that uses a high-density interdigitated electrode to detect rabbit IgG. We show that the response of the biomolecular transistor comprises of: (a) a sub-threshold region where the conductance change is an exponential function of the enhancement time and; (b) an above-threshold region where the conductance change is a linear function with respect to the enhancement time. By exploiting both these regions of operation, it is shown that the silver enhancing time is a reliable indicator of the IgG concentration. The method provides a relatively straightforward alternative to biomolecular signal amplification techniques. The measured results using a biochip prototype fabricated in silicon show that 240 pg/mL rabbit IgG can be detected at the silver enhancing time of 42 min. Also, the biomolecular transistor is compatible with silicon based processing making it ideal for designing integrated CMOS biosensors.

Deposition of dopant impurities and pulsed energy drive-in

DOEpatents

Wickboldt, Paul; Carey, Paul G.; Smith, Patrick M.; Ellingboe, Albert R.

2008-01-01

A semiconductor doping process which enhances the dopant incorporation achievable using the Gas Immersion Laser Doping (GILD) technique. The enhanced doping is achieved by first depositing a thin layer of dopant atoms on a semiconductor surface followed by exposure to one or more pulses from either a laser or an ion-beam which melt a portion of the semiconductor to a desired depth, thus causing the dopant atoms to be incorporated into the molten region. After the molten region recrystallizes the dopant atoms are electrically active. The dopant atoms are deposited by plasma enhanced chemical vapor deposition (PECVD) or other known deposition techniques.

Deposition of dopant impurities and pulsed energy drive-in

DOEpatents

Wickboldt, Paul; Carey, Paul G.; Smith, Patrick M.; Ellingboe, Albert R.

1999-01-01

A semiconductor doping process which enhances the dopant incorporation achievable using the Gas Immersion Laser Doping (GILD) technique. The enhanced doping is achieved by first depositing a thin layer of dopant atoms on a semiconductor surface followed by exposure to one or more pulses from either a laser or an ion-beam which melt a portion of the semiconductor to a desired depth, thus causing the dopant atoms to be incorporated into the molten region. After the molten region recrystallizes the dopant atoms are electrically active. The dopant atoms are deposited by plasma enhanced chemical vapor deposition (PECVD) or other known deposition techniques.

Deposition of dopant impurities and pulsed energy drive-in

DOEpatents

Wickboldt, P.; Carey, P.G.; Smith, P.M.; Ellingboe, A.R.

1999-06-29

A semiconductor doping process which enhances the dopant incorporation achievable using the Gas Immersion Laser Doping (GILD) technique is disclosed. The enhanced doping is achieved by first depositing a thin layer of dopant atoms on a semiconductor surface followed by exposure to one or more pulses from either a laser or an ion-beam which melt a portion of the semiconductor to a desired depth, thus causing the dopant atoms to be incorporated into the molten region. After the molten region recrystallizes the dopant atoms are electrically active. The dopant atoms are deposited by plasma enhanced chemical vapor deposition (PECVD) or other known deposition techniques. 2 figs.

Tip-enhanced near-field optical microscopy

PubMed Central

Mauser, Nina; Hartschuh, Achim

2013-01-01

Tip-enhanced near-field optical microscopy (TENOM) is a scanning probe technique capable of providing a broad range of spectroscopic information on single objects and structured surfaces at nanometer spatial resolution and with highest detection sensitivity. In this review, we first illustrate the physical principle of TENOM that utilizes the antenna function of a sharp probe to efficiently couple light to excitations on nanometer length scales. We then discuss the antenna-induced enhancement of different optical sample responses including Raman scattering, fluorescence, generation of photocurrent and electroluminescence. Different experimental realizations are presented and several recent examples that demonstrate the capabilities of the technique are reviewed. PMID:24100541

[Application of surface-enhanced Raman spectra to the analysis of Chinese Ephedra soup medicines].

PubMed

Zhang, J; Wang, Y

1998-06-01

A new method was developed to analyse the spectra of ephedrine in Chinese ephedra soup medicines, using surface-enhanced technique to combine thin layer chromatographic (TLC) technique with surface-enhanced Raman spectroscopy (SERS). The study indicates that the main vibrant characteristic spec tral band of the ephedrine molecules can be obtained by TLC in the samples of about 8 microg, and expounds char acteristics of the sample molecules and the silica gel. Therefore, it is clarified that the main chemical composi tion of Chinese medicines can be carried as finger-print type appraisal by combining TLC and SERS.

Detecting fluorescence hot-spots using mosaic maps generated from multimodal endoscope imaging

NASA Astrophysics Data System (ADS)

Yang, Chenying; Soper, Timothy D.; Seibel, Eric J.

2013-03-01

Fluorescence labeled biomarkers can be detected during endoscopy to guide early cancer biopsies, such as high-grade dysplasia in Barrett's Esophagus. To enhance intraoperative visualization of the fluorescence hot-spots, a mosaicking technique was developed to create full anatomical maps of the lower esophagus and associated fluorescent hot-spots. The resultant mosaic map contains overlaid reflectance and fluorescence images. It can be used to assist biopsy and document findings. The mosaicking algorithm uses reflectance images to calculate image registration between successive frames, and apply this registration to simultaneously acquired fluorescence images. During this mosaicking process, the fluorescence signal is enhanced through multi-frame averaging. Preliminary results showed that the technique promises to enhance the detectability of the hot-spots due to enhanced fluorescence signal.

An Efficient VLSI Architecture of the Enhanced Three Step Search Algorithm

NASA Astrophysics Data System (ADS)

Biswas, Baishik; Mukherjee, Rohan; Saha, Priyabrata; Chakrabarti, Indrajit

2016-09-01

The intense computational complexity of any video codec is largely due to the motion estimation unit. The Enhanced Three Step Search is a popular technique that can be adopted for fast motion estimation. This paper proposes a novel VLSI architecture for the implementation of the Enhanced Three Step Search Technique. A new addressing mechanism has been introduced which enhances the speed of operation and reduces the area requirements. The proposed architecture when implemented in Verilog HDL on Virtex-5 Technology and synthesized using Xilinx ISE Design Suite 14.1 achieves a critical path delay of 4.8 ns while the area comes out to be 2.9K gate equivalent. It can be incorporated in commercial devices like smart-phones, camcorders, video conferencing systems etc.

Diffraction enhance x-ray imaging for quantitative phase contrast studies

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

Agrawal, A. K.; Singh, B., E-mail: balwants@rrcat.gov.in; Kashyap, Y. S.

2016-05-23

Conventional X-ray imaging based on absorption contrast permits limited visibility of feature having small density and thickness variations. For imaging of weakly absorbing material or materials possessing similar densities, a novel phase contrast imaging techniques called diffraction enhanced imaging has been designed and developed at imaging beamline Indus-2 RRCAT Indore. The technique provides improved visibility of the interfaces and show high contrast in the image forsmall density or thickness gradients in the bulk. This paper presents basic principle, instrumentation and analysis methods for this technique. Initial results of quantitative phase retrieval carried out on various samples have also been presented.

Development and evaluation of vision rehabilitation devices.

PubMed

Luo, Gang; Peli, Eli

2011-01-01

We have developed a range of vision rehabilitation devices and techniques for people with impaired vision due to either central vision loss or severely restricted peripheral visual field. We have conducted evaluation studies with patients to test the utilities of these techniques in an effort to document their advantages as well as their limitations. Here we describe our work on a visual field expander based on a head mounted display (HMD) for tunnel vision, a vision enhancement device for central vision loss, and a frequency domain JPEG/MPEG based image enhancement technique. All the evaluation studies included visual search paradigms that are suitable for conducting indoor controllable experiments.

A new simple technique for improving the random properties of chaos-based cryptosystems

NASA Astrophysics Data System (ADS)

Garcia-Bosque, M.; Pérez-Resa, A.; Sánchez-Azqueta, C.; Celma, S.

2018-03-01

A new technique for improving the security of chaos-based stream ciphers has been proposed and tested experimentally. This technique manages to improve the randomness properties of the generated keystream by preventing the system to fall into short period cycles due to digitation. In order to test this technique, a stream cipher based on a Skew Tent Map algorithm has been implemented on a Virtex 7 FPGA. The randomness of the keystream generated by this system has been compared to the randomness of the keystream generated by the same system with the proposed randomness-enhancement technique. By subjecting both keystreams to the National Institute of Standards and Technology (NIST) tests, we have proved that our method can considerably improve the randomness of the generated keystreams. In order to incorporate our randomness-enhancement technique, only 41 extra slices have been needed, proving that, apart from effective, this method is also efficient in terms of area and hardware resources.

EDITORIAL: Imaging systems and techniques Imaging systems and techniques

NASA Astrophysics Data System (ADS)

Yang, Wuqiang; Giakos, George; Nikita, Konstantina; Pastorino, Matteo; Karras, Dimitrios

2009-10-01

The papers in this special issue focus on providing the state-of-the-art approaches and solutions to some of the most challenging imaging areas, such as the design, development, evaluation and applications of imaging systems, measuring techniques, image processing algorithms and instrumentation, with an ultimate aim of enhancing the measurement accuracy and image quality. This special issue explores the principles, engineering developments and applications of new imaging systems and techniques, and encourages broad discussion of imaging methodologies, shaping the future and identifying emerging trends. The multi-faceted field of imaging requires drastic adaptation to the rapid changes in our society, economy, environment and technological evolution. There is an urgent need to address new problems, which tend to be either static but complex, or dynamic, e.g. rapidly evolving with time, with many unknowns, and to propose innovative solutions. For instance, the battles against cancer and terror, monitoring of space resources and enhanced awareness, management of natural resources and environmental monitoring are some of the areas that need to be addressed. The complexity of the involved imaging scenarios and demanding design parameters, e.g. speed, signal-to-noise ratio (SNR), specificity, contrast, spatial resolution, scatter rejection, complex background and harsh environments, necessitate the development of a multi-functional, scalable and efficient imaging suite of sensors, solutions driven by innovation, and operation on diverse detection and imaging principles. Efficient medical imaging techniques capable of providing physiological information at the molecular level present another important research area. Advanced metabolic and functional imaging techniques, operating on multiple physical principles, and using high-resolution, high-selectivity nano-imaging methods, quantum dots, nanoparticles, biomarkers, nanostructures, nanosensors, micro-array imaging chips and nano-clinics for optical diagnostics and targeted therapy, can play an important role in the diagnosis and treatment of cancer. These techniques can also be used to provide efficient drug delivery for treatment of other diseases, with increased sensitivity and specificity. Similarly, enhanced stand-off detection, classification, identification and surveillance techniques, for comprehensive civilian and military target protection and enhanced space situational awareness can open new frontiers of research and applications in the defence arena and homeland security. For instance, the development of potential imaging sensor architectures, enhanced remote sensing systems, ladars, lidars and radars can provide data capable of ensuring continuous monitoring of various imaging/physical/chemical parameters under different operating conditions, using both active and passive detection principles, reconfigurable and scalable focal plane array architectures, reliable systems for stand-off detection of explosives, and enhanced airport security. The above areas pose challenging problems to the technical community and indicate an ever-growing need for innovative and auspicious solutions. We would like to thank all authors for their valuable contributions, without which this special issue would not have become reality.

Effect of 16-Day Spaceflight on the Morphology of Thick-Toed Geckos (Pachydactylus Bibronii Smith, 1846)

NASA Technical Reports Server (NTRS)

Gulimova, V. I.; Nikitin, V. B.; Asadchikov, V. E.; Buzmakov, A. V.; Okshtein, I. L.; Almeida, E. A. C.; Ilyin, E. A.; Tairbekov, M. G.; Saveliev, S. V.

2006-01-01

There are grounds to believe that space flown experiments on thick-toed geckos may help solve the problem of floatation of vertebrates in microgravity. Geckos of this species carry on the lower surface of their toes numerous setae, which allow them to remain attached to any surfaces regardless of the gravitational effects. Experiments were performed on 5 animals in each of the following groups: flight, basal, synchronous and laboratory controls. 32 hours after a 16- day flight the animals were euthanazed and examined using traditional histology and X-ray microtomography. Body mass losses were 10% in the flight animals, 7.4% in the synchronous controls, and 12.3% in the laboratory controls. Since the flight and synchronous animals were kept at 15-19 C, whereas the laboratory controls - at 26-28 C, it can be inferred that environmental temperatures impacted animal metabolism no less than flight induced stress. Blood tests of the flown animals showed a 12% decrease of erythrocytes and a 40% decrease of dark-nuclear granulocytes, with the number of light-nuclear granulocytes remaining unchanged. In the small intestine the number of goblet cells increased allowing them to occupy a large portion of the cyptal surface. Enhanced secretion was accompanied by the appearance of dead intestinal cells in the lumen. Clusters of degraded hepatocytes were found at the liver edges of flight animals. Signs of liver involution were similar to the changes produced by alcohol consumption but did not spread to its central part. In the heart, insignificant hypertrophy and excessive blood supply that still remained within the physiological norm were detected. No significant changes were found in the pancreas, lungs, nervous systems or the snouts of the flown animals, but the volume of their gallbladders was greater than in controls. The epithelium of toe pads of the flight animals became thinner. Histological examination of the humerus did not demonstrate significant mineral losses. However, X-ray microtomography showed changes in the trabecular structure in the subepyphyseal zone of bones in flight animals compared to the controls. In summary, all the changes detected in the flight animals were adaptive. Therefore, geckos of this species can be used as an animal model for morphological studies in longer-duration space flights.

Integrating Technology-Enhanced Collaborative Surfaces and Gamification for the Next Generation Classroom

ERIC Educational Resources Information Center

Barneva, Reneta P.; Kanev, Kamen; Kapralos, Bill; Jenkin, Michael; Brimkov, Boris

2017-01-01

We place collaborative student engagement in a nontraditional perspective by considering a novel, more interactive educational environment and explaining how to employ it to enhance student learning. To this end, we explore modern technological classroom enhancements as well as novel pedagogical techniques which facilitate collaborative learning.…

75 FR 4615 - Agency Information Collection Activities: Notice of Request for Extension of Currently Approved...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-28

... educational programs relating to the history and construction techniques of historic covered bridges... cultural tourism or enhances the history/ economic development of the community; and other benefits upon... preservation efforts; how it enhances cultural tourism or enhances the history/ economic development of the...

Pterin detection using surface-enhanced Raman spectroscopy incorporating a straightforward silver colloid-based synthesis technique

NASA Astrophysics Data System (ADS)

Smyth, Ciarán A.; Mehigan, Sam; Rakovich, Yury P.; Bell, Steven E. J.; McCabe, Eithne M.

2011-07-01

Optical techniques toward the realization of sensitive and selective biosensing platforms have received considerable attention in recent times. Techniques based on interferometry, surface plasmon resonance, and waveguides have all proved popular, while spectroscopy in particular offers much potential. Raman spectroscopy is an information-rich technique in which the vibrational frequencies reveal much about the structure of a compound, but it is a weak process and offers poor sensitivity. In response to this problem, surface-enhanced Raman scattering (SERS) has received much attention, due to significant increases in sensitivity instigated by bringing the sample into contact with an enhancing substrate. Here we discuss a facile and rapid technique for the detection of pterins using SERS-active colloidal silver suspensions. Pterins are a family of biological compounds that are employed in nature in color pigmentation and as facilitators in metabolic pathways. In this work, small volumes of xanthopterin, isoxanthopterin, and 7,8-dihydrobiopterin have been examined while adsorbed to silver colloids. Limits of detection have been examined for both xanthopterin and isoxanthopterin using a 10-s exposure to a 12 mW 532 nm laser, which, while showing a trade-off between scan time and signal intensity, still provides the opportunity for the investigation of simultaneous detection of both pterins in solution.

A Sparsity-based Framework for Resolution Enhancement in Optical Fault Analysis of Integrated Circuits

DTIC Science & Technology

2015-01-01

for IC fault detection . This section provides background information on inversion methods. Conventional inversion techniques and their shortcomings are...physical techniques, electron beam imaging/analysis, ion beam techniques, scanning probe techniques. Electrical tests are used to detect faults in 13 an...hand, there is also the second harmonic technique through which duty cycle degradation faults are detected by collecting the magnitude and the phase of

Re-impacting Debris Facilitated Cooling of the Lunar Magma Ocean

NASA Astrophysics Data System (ADS)

Perera, Viranga; Jackson, Alan; Elkins-Tanton, Linda T.; Asphaug, Erik

2017-10-01

It is widely believed that the Moon formed from the debris of a giant impact between the proto-Earth and a roughly Mars-sized body. Concomitant to this formation scenario, and also inferred from geochemical analyses of Apollo samples, is the past existence of a Lunar Magma Ocean (LMO). After about 80% of the LMO solidified, it is believed that the mineral plagioclase would have become stable and crystallized out of the LMO. Rocks that formed principally of plagioclase would have been buoyant in the residual liquid and thus helped form a floatation crust that acted as a thermally conductive blanket over the LMO. Previous modelling work found that the LMO would have solidified in about 10 Myr. However, studies have shown that, during the giant impact event, a large quantity of debris (totaling over a Lunar mass) would have been released that was not immediately incorporated into the Earth and the Moon. This material would have subsequently re-impacted the Earth and the Moon. Particularly for the Moon, this debris would have punctured holes into the nascent lunar crust, attenuated its thermal blanketing effect, and thus facilitated the cooling of the LMO. We improve upon previous studies of the solidification of the LMO by incorporating this re-impacting debris, and find that the re-impacting debris may have reduced the LMO solidification time.

Controlled Bulk Properties of Composite Polymeric Solutions for Extensive Structural Order of Honeycomb Polysulfone Membranes

PubMed Central

Gugliuzza, Annarosa; Perrotta, Maria Luisa; Drioli, Enrico

2016-01-01

This work provides additional insights into the identification of operating conditions necessary to overcome a current limitation to the scale-up of the breath figure method, which is regarded as an outstanding manufacturing approach for structurally ordered porous films. The major restriction concerns, indeed, uncontrolled touching droplets at the boundary. Herein, the bulk of polymeric solutions are properly managed to generate honeycomb membranes with a long-range structurally ordered texture. Water uptake and dynamics are explored as chemical environments are changed with the intent to modify the hydrophilic/hydrophobic balance and local water floatation. In this context, a model surfactant such as the polyoxyethylene sorbitan monolaurate is used in combination with alcohols at different chain length extents and a traditional polymer such as the polyethersufone. Changes in the interfacial tension and kinematic viscosity taking place in the bulk of composite solutions are explored and examined in relation to competitive droplet nucleation and growth rate. As a result, extensive structurally ordered honeycomb textures are obtained with the rising content of the surfactant while a broad range of well-sized pores is targeted as a function of the hydrophilic-hydrophobic balance and viscosity of the composite polymeric mixture. The experimental findings confirm the consistency of the approach and are expected to give propulsion to the commercially production of breath figures films shortly. PMID:27196938

Controlled Bulk Properties of Composite Polymeric Solutions for Extensive Structural Order of Honeycomb Polysulfone Membranes.

PubMed

Gugliuzza, Annarosa; Perrotta, Maria Luisa; Drioli, Enrico

2016-05-16

This work provides additional insights into the identification of operating conditions necessary to overcome a current limitation to the scale-up of the breath figure method, which is regarded as an outstanding manufacturing approach for structurally ordered porous films. The major restriction concerns, indeed, uncontrolled touching droplets at the boundary. Herein, the bulk of polymeric solutions are properly managed to generate honeycomb membranes with a long-range structurally ordered texture. Water uptake and dynamics are explored as chemical environments are changed with the intent to modify the hydrophilic/hydrophobic balance and local water floatation. In this context, a model surfactant such as the polyoxyethylene sorbitan monolaurate is used in combination with alcohols at different chain length extents and a traditional polymer such as the polyethersufone. Changes in the interfacial tension and kinematic viscosity taking place in the bulk of composite solutions are explored and examined in relation to competitive droplet nucleation and growth rate. As a result, extensive structurally ordered honeycomb textures are obtained with the rising content of the surfactant while a broad range of well-sized pores is targeted as a function of the hydrophilic-hydrophobic balance and viscosity of the composite polymeric mixture. The experimental findings confirm the consistency of the approach and are expected to give propulsion to the commercially production of breath figures films shortly.

Practical parasitology courses and infection with intestinal parasites in students.

PubMed

Fallahi, Sh; Rostami, A; Mohammadi, M; Ebrahimzadeh, F; Pournia, Y

2016-01-01

Students who are working in research or educational laboratories of parasitology, as well as health care workers providing care for patients, are at the risk of becoming infected with parasites through accidental exposure. The main purpose of this study was to identify potential positive cases of intestinal parasitic infections among students who took practical parasitology courses compared with students who did not take any practical parasitology courses in Lorestan University of Medical Sciences, Khorramabad, Iran, in 2013-2014. A total of 310 subjects from various majors were invited to voluntarily participate in the study. Various demographic data were collected using questionnaires. Three stool samples were collected from each individual on alternate days. Saline wet mounts (SWM), formalin-ether sedimentation test (FEST), Sheather floatation test (SHFT) and trichrome and modified Ziehl-Neelsen staining methods were used to diagnose the presence of intestinal parasites. The prevalence rate of intestinal parasites (IPs) among the students was 11.93%. There was a significant difference between majors in the infection with IPs (P<0.05). The most frequently observed IPs were Blastocystis hominis (4.51%) and Giardia intestinalis (3.54%). The results of this study showed that the transmission of pathogenic parasites in the educational course of practical parasitology could occur and must be taken into careful consideration. Copyright © 2015 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Greenland Regional and Ice Sheet-wide Geometry Sensitivity to Boundary and Initial conditions

NASA Astrophysics Data System (ADS)

Logan, L. C.; Narayanan, S. H. K.; Greve, R.; Heimbach, P.

2017-12-01

Ice sheet and glacier model outputs require inputs from uncertainly known initial and boundary conditions, and other parameters. Conservation and constitutive equations formalize the relationship between model inputs and outputs, and the sensitivity of model-derived quantities of interest (e.g., ice sheet volume above floatation) to model variables can be obtained via the adjoint model of an ice sheet. We show how one particular ice sheet model, SICOPOLIS (SImulation COde for POLythermal Ice Sheets), depends on these inputs through comprehensive adjoint-based sensitivity analyses. SICOPOLIS discretizes the shallow-ice and shallow-shelf approximations for ice flow, and is well-suited for paleo-studies of Greenland and Antarctica, among other computational domains. The adjoint model of SICOPOLIS was developed via algorithmic differentiation, facilitated by the source transformation tool OpenAD (developed at Argonne National Lab). While model sensitivity to various inputs can be computed by costly methods involving input perturbation simulations, the time-dependent adjoint model of SICOPOLIS delivers model sensitivities to initial and boundary conditions throughout time at lower cost. Here, we explore both the sensitivities of the Greenland Ice Sheet's entire and regional volumes to: initial ice thickness, precipitation, basal sliding, and geothermal flux over the Holocene epoch. Sensitivity studies such as described here are now accessible to the modeling community, based on the latest version of SICOPOLIS that has been adapted for OpenAD to generate correct and efficient adjoint code.

Group aquatic training improves gait efficiency in adolescents with cerebral palsy.

PubMed

Ballaz, Laurent; Plamondon, Suzanne; Lemay, Martin

2011-01-01

To evaluate the effect and feasibility of a 10-week group aquatic training programme on gait efficiency in adolescents with cerebral palsy (CP). The secondary purpose was to determine the exercise intensity during aquatic training in a heterogeneous group of adolescents with CP and to investigate the impact of the training programme on the musculoskeletal system. Twelve ambulatory adolescents with spastic CP were recruited. They participated in 20 aquatic training sessions (45 min twice a week). Three physical therapists and a sports teacher supervised the training sessions. Participants wore a heart rate monitor to assess sessions' intensity and a floatation device as appropriate. The primary outcome measure was gait efficiency as measured by the gait energy expenditure index (EEI). The secondary measures were (1) gait spatiotemporal parameters, (2) maximal isometric knee strength and (3) gross motor function. Ten adolescents completed the training programme. No adverse effect was reported. Average exercise intensity was mild to moderate for more than half of the training session. A significant reduction of the EEI and the heart rate during walking was observed following the training programme. No significant change was observed on secondary outcome measures. Group aquatic training increases gait efficiency in adolescents with CP. This improvement is related to systemic cardiorespiratory adaptations. Group aquatic training programme is feasible in adolescents presenting CP at different levels of severity.

Aggregation of MBP in chronic demyelination

PubMed Central

Frid, Kati; Einstein, Ofira; Friedman-Levi, Yael; Binyamin, Orli; Ben-Hur, Tamir; Gabizon, Ruth

2015-01-01

Objectives Misfolding of key disease proteins to an insoluble state is associated with most neurodegenerative conditions, such as prion, Parkinson, and Alzheimer’s diseases. In this work, and by studying animal models of multiple sclerosis, we asked whether this is also the case for myelin basic protein (MBP) in the late and neurodegenerative phases of demyelinating diseases. Methods To this effect, we tested whether MBP, an essential myelin component, present prion-like properties in animal models of MS, as is the case for Cuprizone-induced chronic demyelination or chronic phases of Experimental Autoimmune Encephalomyelitis (EAE). Results We show here that while total levels of MBP were not reduced following extensive demyelination, part of these molecules accumulated thereafter as aggregates inside oligodendrocytes or around neuronal cells. In chronic EAE, MBP precipitated concomitantly with Tau, a marker of diverse neurodegenerative conditions, including MS. Most important, analysis of fractions from Triton X-100 floatation gradients suggest that the lipid composition of brain membranes in chronic EAE differs significantly from that of naïve mice, an effect which may relate to oxidative insults and subsequently prevent the appropriate insertion and compaction of new MBP in the myelin sheath, thereby causing its misfolding and aggregation. Interpretation Prion-like aggregation of MBP following chronic demyelination may result from an aberrant lipid composition accompanying this pathological status. Such aggregation of MBP may contribute to neuronal damage that occurs in the progressive phase of MS. PMID:26273684

Different populations of Wnt-containing vesicles are individually released from polarized epithelial cells

PubMed Central

Chen, Qiuhong; Takada, Ritsuko; Noda, Chiyo; Kobayashi, Satoru; Takada, Shinji

2016-01-01

Accumulating evidence suggests that exosomes are heterogeneous in molecular composition and physical properties. Here we examined whether epithelial cells secrete a heterogeneous population of exosomes, and if that is the case, whether epithelial cell polarity affects release of different populations of exosomes, especially that of those carrying Wnt. Sucrose-density ultracentrifugation and molecular marker analysis revealed that different populations of exosomes or exosome-like vesicles were released from MDCK cells depending on the cell polarity. Wnt3a associated with these vesicles were detectable in culture media collected from both apical and basolateral sides of the cells. Basolaterally secreted Wnt3a were co-fractionated with a typical exosomal protein TSG101 in fractions having typical exosome densities. In contrast, most of apically secreted Wnt3a, as well as Wnt11, were co-fractionated with CD63 and Hsp70, which are also common to the most exosomes, but recovered in higher density fractions. Wnt3a exhibiting similar floatation behavior to the apically secreted ones were also detectable in the culture media of Wnt3a-expressing L and HEK293 cells. The lipidation of Wnt3a was required for its basolateral secretion in exosomes but was dispensable for the apical one. Thus, epithelial cells release Wnt via distinct populations of vesicles differing in secretion polarity and lipidation dependency. PMID:27765945

Evaluation of water uptake and mechanical properties of blended polymer films for preparing gas-generated multiple-unit floating drug delivery systems.

PubMed

Chen, Ying-Chen; Lee, Lin-Wen; Ho, Hsiu-O; Sha, Chen; Sheu, Ming-Thau

2012-10-01

Among various strategies of gastroretentive drug delivery systems (DDSs) developed to prolong the gastric residence time and to increase the overall bioavailability, effervescent multiple-unit floating DDSs (muFDDSs) were studied here. These systems consist of drug (losartan)- and effervescent (sodium bicarbonate)-containing pellets coated with a blended polymeric membrane, which was a mixture of gastrointestinal tract (GIT)-soluble and GIT-insoluble polymers. The addition of GIT-soluble polymers, such as hydroxypropyl methylcellulose, polyethylene glycol (PEG) 6000, PEG 600, and Kollicoat® IR, greatly increased the water uptake ability of the GIT-insoluble polymers (Eudragit® NE, RS, and RL; Surelease®; and Kollicoat® SR) and caused them to immediately initiate the effervescent reaction and float, but the hydrated films should also be impermeable to the generated CO(2) to maintain floatation and sufficiently flexible to withstand the pressure of carbon dioxide to avoid rupturing. The study demonstrated that the water uptake ability and mechanical properties could be applied as screening tools during the development of effervescent muFDDSs. The optimized system of SRT(5)P600(5) (i.e., a mixture of 5% Kollicoat® SR and 5% PEG 600) with a 20% coating level began to completely float within 15 min and maintained its buoyancy over a period of 12 h with a sustained-release effect. Copyright © 2012 Wiley Periodicals, Inc.

Formulation and evaluation of atenolol floating bioadhesive system using optimized polymer blends

PubMed Central

Siddam, Haritha; Kotla, Niranjan G.; Maddiboyina, Balaji; Singh, Sima; Sunnapu, Omprakash; Kumar, Anil; Sharma, Dinesh

2016-01-01

Introduction: Oral sustained release gastro retentive dosage forms offer several advantages for drugs having absorption from the upper gastrointestinal tract to improve the bioavailability of medications which have narrow absorption window. The aim of the study was to develop a floating bioadhesive drug delivery system exhibiting a unique combination of floatation and bioadhesion to prolong the residence in the stomach using atenolol as a model drug. Methods: Prior to compression, polymeric blend(s) were evaluated for flow properties. The tablets were prepared by direct compression method using bioadhesive polymer like Carbopol 934P and hydrophilic polymers like HPMC K4M, HPMC K15M, and HPMC K100M. The prepared tablets were evaluated for physical characteristics, bioadhesive strength, buoyancy lag time, swelling index and in vitro drug release studies. Results: The mean bioadhesive strength was found to be in the range of 16.2 to 52.1 gm. The optimized blend (F11) showed 92.3% drug releases after 24 hrs. Whilst, increase in concentration of carbopol 934P, bioadhesive strength and swelling index was increased with slow release. The n values of optimized formulations were found in the range of 0.631-0.719 indicating non-fickian anomalous type transport mechanism. Conclusion: The study aided in developing an ideal once-a-day gastro retentive floating drug delivery system with improved floating, swelling and bioadhesive characteristics with better bioavailability. PMID:27051631

Hollow microspheres of diclofenac sodium - a gastroretentive controlled delivery system.

PubMed

Bv, Basavaraj; R, Deveswaran; S, Bharath; Abraham, Sindhu; Furtado, Sharon; V, Madhavan

2008-10-01

Most of the floating systems have an inherent drawback of high variability in the GI transit time, invariably affecting the bioavailability of drug. To overcome it, a multiple unit floating system with extended GI transit time, capable of distributing widely throughout the GIT for effective enteric release of the drug has been sought. Microballoons loaded with drug in their outer polymer shells were prepared by novel emulsion solvent diffusion method. The ethanol: dicloromethane solution of drug and Eudragit-S were poured into an aqueous solution of PVA that was thermally controlled at 40 degrees C. The gas phase generated in the dispersed polymer droplet by the evaporation of solvent formed an internal cavity in the microsphere of the polymer with the drug. The flowability of the resulting microballoons improved when compared to pure drug. The microballoons on floatation along with the surfactant, floated continuously for more than 12 hours in the acidic medium in-vitro conditions. The in-vitro drug release profile of the formulation in the simulated gastric buffer showed no drug release, which emphasizes the enteric release property and in simulated intestinal buffer, a slow and controlled drug release of 60 to 84% was obtained over a period of 8 hours. Drug release was significantly affected by increased drug to polymer concentration at pH 6.8. The formulation was found to be physically and chemically stable as per the ICH guidelines.

Interferometric at-wavelength flare characterization of EUV optical systems

DOEpatents

Naulleau, Patrick P.; Goldberg, Kenneth Alan

2001-01-01

The extreme ultraviolet (EUV) phase-shifting point diffraction interferometer (PS/PDI) provides the high-accuracy wavefront characterization critical to the development of EUV lithography systems. Enhancing the implementation of the PS/PDI can significantly extend its spatial-frequency measurement bandwidth. The enhanced PS/PDI is capable of simultaneously characterizing both wavefront and flare. The enhanced technique employs a hybrid spatial/temporal-domain point diffraction interferometer (referred to as the dual-domain PS/PDI) that is capable of suppressing the scattered-reference-light noise that hinders the conventional PS/PDI. Using the dual-domain technique in combination with a flare-measurement-optimized mask and an iterative calculation process for removing flare contribution caused by higher order grating diffraction terms, the enhanced PS/PDI can be used to simultaneously measure both figure and flare in optical systems.

Geological and Structural Patterns on Titan Enhanced Through Cassini's SAR PCA and High-Resolution Radiometry

NASA Astrophysics Data System (ADS)

Paganelli, F.; Schubert, G.; Lopes, R. M. C.; Malaska, M.; Le Gall, A. A.; Kirk, R. L.

2016-12-01

The current SAR data coverage on Titan encompasses several areas in which multiple radar passes are present and overlapping, providing additional information to aid the interpretation of geological and structural features. We exploit the different combinations of look direction and variable incidence angle to examine Cassini Synthetic Aperture RADAR (SAR) data using the Principal Component Analysis (PCA) technique and high-resolution radiometry, as a tool to aid in the interpretation of geological and structural features. Look direction and variable incidence angle is of particular importance in the analysis of variance in the images, which aid in the perception and identification of geological and structural features, as extensively demonstrated in Earth and planetary examples. The PCA enhancement technique uses projected non-ortho-rectified SAR imagery in order to maintain the inherent differences in scattering and geometric properties due to the different look directions, while enhancing the geometry of surface features. The PC2 component provides a stereo view of the areas in which complex surface features and structural patterns can be enhanced and outlined. We focus on several areas of interest, in older and recently acquired flybys, in which evidence of geological and structural features can be enhanced and outlined in the PC1 and PC2 components. Results of this technique provide enhanced geometry and insights into the interpretation of the observed geological and structural features, thus allowing a better understanding towards the geology and tectonics on Titan.

Collaborative Learning in the Dance Technique Class

ERIC Educational Resources Information Center

Raman, Tanja

2009-01-01

This research was designed to enhance dance technique learning by promoting critical thinking amongst students studying on a degree programme at the University of Wales Institute, Cardiff. Students were taught Cunningham-based dance technique using pair work together with the traditional demonstration/copying method. To evaluate the study,…

Exploring Childhood Memories with Adult Survivors of Sexual Abuse: Concrete Reconstruction and Visualization Techniques.

ERIC Educational Resources Information Center

Roland, Catherine B.

1993-01-01

Describes two memory-enhancing techniques, visualization and concrete reconstruction, that have been successful in counseling adult survivors of sexual abuse. Includes suggested implementations, case examples, and implications for incorporating memory techniques into counseling process. Describes various risk factors involved in using these…

Fusing Observations and Model Results for Creation of Enhanced Ozone Spatial Fields: Comparison of Three Techniques

EPA Science Inventory

This paper presents three simple techniques for fusing observations and numerical model predictions. The techniques rely on model/observation bias being considered either as error free, or containing some uncertainty, the latter mitigated with a Kalman filter approach or a spati...

Application of the Overclaiming Technique to Scholastic Assessment

ERIC Educational Resources Information Center

Paulhus, Delroy L.; Dubois, Patrick J.

2014-01-01

The overclaiming technique is a novel assessment procedure that uses signal detection analysis to generate indices of knowledge accuracy (OC-accuracy) and self-enhancement (OC-bias). The technique has previously shown robustness over varied knowledge domains as well as low reactivity across administration contexts. Here we compared the OC-accuracy…

Techniques for Enhancing Web-Based Education.

ERIC Educational Resources Information Center

Barbieri, Kathy; Mehringer, Susan

The Virtual Workshop is a World Wide Web-based set of modules on high performance computing developed at the Cornell Theory Center (CTC) (New York). This approach reaches a large audience, leverages staff effort, and poses challenges for developing interesting presentation techniques. This paper describes the following techniques with their…

Temporal contrast enhancement of a femtosecond fiber CPA system by filtering of SPM broadened spectra

NASA Astrophysics Data System (ADS)

Buldt, J.; Müller, M.; Klas, R.; Eidam, T.; Limpert, J.; Tünnermann, A.

2018-02-01

We present a novel approach for temporal contrast enhancement of energetic laser pulses by filtered SPM broadened spectra. A measured temporal contrast enhancement by at least 7 orders of magnitude in a simple setup has been achieved. This technique is applicable to a wide range of laser parameters and poses a highly efficient alternative to existing contrast-enhancement methods.

A contrast enhancement method for improving the segmentation of breast lesions on ultrasonography.

PubMed

Flores, Wilfrido Gómez; Pereira, Wagner Coelho de Albuquerque

2017-01-01

This paper presents an adaptive contrast enhancement method based on sigmoidal mapping function (SACE) used for improving the computerized segmentation of breast lesions on ultrasound. First, from the original ultrasound image an intensity variation map is obtained, which is used to generate local sigmoidal mapping functions related to distinct contextual regions. Then, a bilinear interpolation scheme is used to transform every original pixel to a new gray level value. Also, four contrast enhancement techniques widely used in breast ultrasound enhancement are implemented: histogram equalization (HEQ), contrast limited adaptive histogram equalization (CLAHE), fuzzy enhancement (FEN), and sigmoid based enhancement (SEN). In addition, these contrast enhancement techniques are considered in a computerized lesion segmentation scheme based on watershed transformation. The performance comparison among techniques is assessed in terms of both the quality of contrast enhancement and the segmentation accuracy. The former is quantified by the measure, where the greater the value, the better the contrast enhancement, whereas the latter is calculated by the Jaccard index, which should tend towards unity to indicate adequate segmentation. The experiments consider a data set with 500 breast ultrasound images. The results show that SACE outperforms its counterparts, where the median values for the measure are: SACE: 139.4, SEN: 68.2, HEQ: 64.1, CLAHE: 62.8, and FEN: 7.9. Considering the segmentation performance results, the SACE method presents the largest accuracy, where the median values for the Jaccard index are: SACE: 0.81, FEN: 0.80, CLAHE: 0.79, HEQ: 77, and SEN: 0.63. The SACE method performs well due to the combination of three elements: (1) the intensity variation map reduces intensity variations that could distort the real response of the mapping function, (2) the sigmoidal mapping function enhances the gray level range where the transition between lesion and background is found, and (3) the adaptive enhancing scheme for coping with local contrasts. Hence, the SACE approach is appropriate for enhancing contrast before computerized lesion segmentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Clustering of financial time series with application to index and enhanced index tracking portfolio

NASA Astrophysics Data System (ADS)

Dose, Christian; Cincotti, Silvano

2005-09-01

A stochastic-optimization technique based on time series cluster analysis is described for index tracking and enhanced index tracking problems. Our methodology solves the problem in two steps, i.e., by first selecting a subset of stocks and then setting the weight of each stock as a result of an optimization process (asset allocation). Present formulation takes into account constraints on the number of stocks and on the fraction of capital invested in each of them, whilst not including transaction costs. Computational results based on clustering selection are compared to those of random techniques and show the importance of clustering in noise reduction and robust forecasting applications, in particular for enhanced index tracking.

Image Processing for Binarization Enhancement via Fuzzy Reasoning

NASA Technical Reports Server (NTRS)

Dominguez, Jesus A. (Inventor)

2009-01-01

A technique for enhancing a gray-scale image to improve conversions of the image to binary employs fuzzy reasoning. In the technique, pixels in the image are analyzed by comparing the pixel's gray scale value, which is indicative of its relative brightness, to the values of pixels immediately surrounding the selected pixel. The degree to which each pixel in the image differs in value from the values of surrounding pixels is employed as the variable in a fuzzy reasoning-based analysis that determines an appropriate amount by which the selected pixel's value should be adjusted to reduce vagueness and ambiguity in the image and improve retention of information during binarization of the enhanced gray-scale image.

Novel Raman Techniques for Imaging and Sensing

NASA Astrophysics Data System (ADS)

Edwards, Perry S.

Raman scattering spectroscopy is extensively demonstrated as a label-free, chemically selective sensing and imaging technique for a multitude of chemical and biological applications. The ability to detect "fingerprint" spectral signatures of individual molecules, without the need to introduce chemical labelers, makes Raman scattering a powerful sensing technique. However, spectroscopy based on spontaneous Raman scattering traditionally suffers from inherently weak signals due to small Raman scattering cross-sections. Thus, considerable efforts have been put forth to find pathways towards enhancing Raman signals to bolster sensitivity for detecting small concentrations of molecules or particles. The development of coherent Raman techniques that can offer orders of magnitude increase in signal have garnered significant interest in recent years for their application in imaging; such techniques include coherent anti-Stokes Raman scattering and stimulated Raman scattering. Additionally, methods to enhance the local field of either the pump or generated Raman signal, such as through surface enhanced Raman scattering, have been investigated for their orders of magnitude improvement in sensitivity and single molecule sensing capability. The work presented in this dissertation describes novel techniques for performing high speed and highly sensitive Raman imaging as well as sensing applications towards bioimaging and biosensing. Coherent anti-Stokes Raman scattering (CARS) is combined with holography to enable recording of high-speed (single laser shot), wide field CARS holograms which can be used to reconstruct the both the amplitude and the phase of the anti-Stokes field therefore allowing 3D imaging. This dissertation explores CARS holography as a viable label-free bio-imaging technique. A Raman scattering particle sensing system is also developed that utilizes wave guide properties of optical fibers and ring-resonators to perform enhanced particle sensing. Resonator-enhanced particle sensing is experimentally examined as a new method for enhancing Raman scattering from particles interacting with circulating optical fields within both a fiber ring-cavity and whispering gallery mode microtoroid microresonators. The achievements described in this dissertation include: (1) Demonstration of the bio-imaging capability of CARS holography by recording of CARS holograms of subcellular components in live cancer (HeLa) cells. (2) Label-free Raman microparticle sensing using a tapered optical fibers. A tapered fiber can guide light to particles adsorbed on the surface of the taper to generate scattered Raman signal which can be collected by a microRaman detection system. (3) Demonstration of the proof of concept of resonator-enhanced Raman spectroscopy in a fiber ring resonator consisting of a section of fiber taper. (4) A method for locking the pump laser to the resonate frequencies of a resonator. This is demonstrated using a fiber ring resonator and microtoroid microresonators. (5) Raman scattered signal from particles adhered to microtoroid microresonators is acquired using 5 seconds of signal integration time and with the pump laser locked to a cavity resonance. (6) Theoretical analysis is performed that indicates resonator-enhanced Raman scattering from microparticles adhered to microresonators can be achieved with the pump laser locked to the frequency of a high-Q cavity resonant mode.

Computer literacy enhancement in the Teaching Hospital Olomouc. Part I: project management techniques. Short communication.

PubMed

Sedlár, Drahomír; Potomková, Jarmila; Rehorová, Jarmila; Seckár, Pavel; Sukopová, Vera

2003-11-01

Information explosion and globalization make great demands on keeping pace with the new trends in the healthcare sector. The contemporary level of computer and information literacy among most health care professionals in the Teaching Hospital Olomouc (Czech Republic) is not satisfactory for efficient exploitation of modern information technology in diagnostics, therapy and nursing. The present contribution describes the application of two basic problem solving techniques (brainstorming, SWOT analysis) to develop a project aimed at information literacy enhancement.

Geological mapping in northwestern Saudi Arabia using LANDSAT multispectral techniques

NASA Technical Reports Server (NTRS)

Blodget, H. W.; Brown, G. F.; Moik, J. G.

1975-01-01

Various computer enhancement and data extraction systems using LANDSAT data were assessed and used to complement a continuing geologic mapping program. Interactive digital classification techniques using both the parallel-piped and maximum-likelihood statistical approaches achieve very limited success in areas of highly dissected terrain. Computer enhanced imagery developed by color compositing stretched MSS ratio data was constructed for a test site in northwestern Saudi Arabia. Initial results indicate that several igneous and sedimentary rock types can be discriminated.

Artwork Separation

NASA Technical Reports Server (NTRS)

1983-01-01

Under a grant from California Institute of Technology, Jet Propulsion Laboratory (JPL) and LACMA (Los Angeles County Museum of Art) used image enhancement techniques to separate x-ray images of paintings when one had been painted on top of another. The technique is derived from computer processing of spacecraft-acquired imagery, and will allow earlier paintings, some of which have been covered for centuries, to be evaluated. JPL developed the program for "subtracting" the top painting and enhancing the bottom one, and believes an even more advanced system is possible.

Understanding ice sheet evolution to avoid massive sea level rise instead of experiencing it (Louis Agassiz Medal Lecture)

NASA Astrophysics Data System (ADS)

Rignot, Eric

2017-04-01

With unabated climate warming, massive sea level rise from the melting of ice sheets in Greenland and Antarctica looms at the horizon. This is unfortunately an experiment that we can afford to run only once. Satellite and airborne sensors have significantly helped reveal the magnitude of the mass balance of the ice sheets, where the changes take place, when they started, how they change with time and the nature of the physical processes controlling them. These observations have constrained the maturation of numerical modeling techniques for projecting changes in these ice sheets, including the coupling of ocean and ice sheet models, yet significant uncertainties remain to make these projections directly policy relevant and many challenges remain. I will review the state of balance of the ice sheets as we know it today and the fundamental processes that will drive fast ice sheet retreat and sea level change: ice-ocean interaction and iceberg calving. Ice-ocean interaction are dominated by the wind-forced intrusion of warm, salty, subsurface waters toward the ice sheet periphery to melt ice from below at rates orders of magnitude greater than at the surface. In Greenland, these rates are difficult to observe, but model simulations indicate rates of ice melt along vertical calving faces of meters per day, along with undercutting of the ice faces. Constraining the temperature of the ocean waters from high resolution models and observations, however, remains a significant challenge. I will describe the progress we have made in addressing one major issue which is the mapping of fjord bathymetry around Greenland to define the pathways for warm waters. In Antarctica, the rates of melt are measured from remote sensing data but averaged over long periods, so that we are dependent on in-situ observations to understand the interaction of ocean waters with ice within the sub-ice-shelf cavities. I will describe progress made in mapping the bathymetry of the ice shelves and how the results have impacted our understanding of these interactions. In terms of calving, there is a range of processes acting upon the glacier and ice shelf faces, proceeding from the surface and mostly from below, that are still not sufficiently well explored. I will discuss processes elucidated in Greenland (undercutting and rotation of ice blocks near floatation) and those that are not well known in Antarctica.

Prevalence of pathogenic free-living amoeba and other protozoa in natural and communal piped tap water from Queen Elizabeth protected area, Uganda.

PubMed

Sente, Celsus; Erume, Joseph; Naigaga, Irene; Mulindwa, Julius; Ochwo, Sylvester; Magambo, Phillip Kimuda; Namara, Benigna Gabriela; Kato, Charles Drago; Sebyatika, George; Muwonge, Kevin; Ocaido, Michael

2016-08-03

Pathogenic water dwelling protozoa such as Acanthamoeba spp., Hartmannella spp., Naegleria spp., Cryptosporidium spp. and Giardia spp. are often responsible for devastating illnesses especially in children and immunocompromised individuals, yet their presence and prevalence in certain environment in sub-Saharan Africa is still unknown to most researchers, public health officials and medical practitioners. The objective of this study was to establish the presence and prevalence of pathogenic free-living amoeba (FLA), Cryptosporidium and Giardia in Queen Elizabeth Protected Area (QEPA). Samples were collected from communal taps and natural water sites in QEPA. Physical water parameters were measured in situ. The samples were processed to detect the presence of FLA trophozoites by xenic cultivation, Cryptosporidium oocysts by Ziehl-Neelsen stain and Giardia cysts by Zinc Sulphate floatation technique. Parasites were observed microscopically, identified, counted and recorded. For FLA, genomic DNA was extracted for amplification and sequencing. Both natural and tap water sources were contaminated with FLA, Cryptosporidium spp. and Giardia spp. All protozoan parasites were more abundant in the colder rainy season except for Harmannella spp. and Naegleria spp. which occurred more in the warmer months. The prevalence of all parasites was higher in tap water than in natural water samples. There was a strong negative correlation between the presence of Acanthamoeba spp., Hartmannella spp., Cryptosporidium spp. and Giardia spp. with Dissolved Oxygen (DO) (P < 0.05). The presence of Cryptosporidium spp. showed a significant positive correlation (P < 0.05) with conductivity, pH and Total Dissolved Solids (TDS); whereas the presence of Giardia spp. had only a strong positive correlation with TDS. Molecular genotyping of FLA produced 7 Acanthamoeba, 5 Echinamoeba, 2 Hartmannella, 1 Bodomorpha, 1 Nuclearia and 1 Cercomonas partial sequences. All water collection sites were found to be contaminated with pathogenic protozoa that could possibly be the cause of a number of silent morbidities and mortalities among rural households in QEPA. This implies that water used by communities in QEPA is of poor quality and predisposes them to a variety of protozoan infections including the FLA whose public health importance was never reported, thus necessitating adoption of proper water safety measures.

High Resolution Imaging of the Sun with CORONAS-1

NASA Technical Reports Server (NTRS)

Karovska, Margarita

1998-01-01

We applied several image restoration and enhancement techniques, to CORONAS-I images. We carried out the characterization of the Point Spread Function (PSF) using the unique capability of the Blind Iterative Deconvolution (BID) technique, which recovers the real PSF at a given location and time of observation, when limited a priori information is available on its characteristics. We also applied image enhancement technique to extract the small scale structure imbeded in bright large scale structures on the disk and on the limb. The results demonstrate the capability of the image post-processing to substantially increase the yield from the space observations by improving the resolution and reducing noise in the images.

Reducing Error Rates for Iris Image using higher Contrast in Normalization process

NASA Astrophysics Data System (ADS)

Aminu Ghali, Abdulrahman; Jamel, Sapiee; Abubakar Pindar, Zahraddeen; Hasssan Disina, Abdulkadir; Mat Daris, Mustafa

2017-08-01

Iris recognition system is the most secured, and faster means of identification and authentication. However, iris recognition system suffers a setback from blurring, low contrast and illumination due to low quality image which compromises the accuracy of the system. The acceptance or rejection rates of verified user depend solely on the quality of the image. In many cases, iris recognition system with low image contrast could falsely accept or reject user. Therefore this paper adopts Histogram Equalization Technique to address the problem of False Rejection Rate (FRR) and False Acceptance Rate (FAR) by enhancing the contrast of the iris image. A histogram equalization technique enhances the image quality and neutralizes the low contrast of the image at normalization stage. The experimental result shows that Histogram Equalization Technique has reduced FRR and FAR compared to the existing techniques.

Second principle approach to the analysis of unsteady flow and heat transfer in a tube with arc-shaped corrugation

NASA Astrophysics Data System (ADS)

Pagliarini, G.; Vocale, P.; Mocerino, A.; Rainieri, S.

2017-01-01

Passive convective heat transfer enhancement techniques are well known and widespread tool for increasing the efficiency of heat transfer equipment. In spite of the ability of the first principle approach to forecast the macroscopic effects of the passive techniques for heat transfer enhancement, namely the increase of both the overall heat exchanged and the head losses, a first principle analysis based on energy, momentum and mass local conservation equations is hardly able to give a comprehensive explanation of how local modifications in the boundary layers contribute to the overall effect. A deeper insight on the heat transfer enhancement mechanisms can be instead obtained within a second principle approach, through the analysis of the local exergy dissipation phenomena which are related to heat transfer and fluid flow. To this aim, the analysis based on the second principle approach implemented through a careful consideration of the local entropy generation rate seems the most suitable, since it allows to identify more precisely the cause of the loss of efficiency in the heat transfer process, thus providing a useful guide in the choice of the most suitable heat transfer enhancement techniques.

Chain of evidence generation for contrast enhancement in digital image forensics

NASA Astrophysics Data System (ADS)

Battiato, Sebastiano; Messina, Giuseppe; Strano, Daniela

2010-01-01

The quality of the images obtained by digital cameras has improved a lot since digital cameras early days. Unfortunately, it is not unusual in image forensics to find wrongly exposed pictures. This is mainly due to obsolete techniques or old technologies, but also due to backlight conditions. To extrapolate some invisible details a stretching of the image contrast is obviously required. The forensics rules to produce evidences require a complete documentation of the processing steps, enabling the replication of the entire process. The automation of enhancement techniques is thus quite difficult and needs to be carefully documented. This work presents an automatic procedure to find contrast enhancement settings, allowing both image correction and automatic scripting generation. The technique is based on a preprocessing step which extracts the features of the image and selects correction parameters. The parameters are thus saved through a JavaScript code that is used in the second step of the approach to correct the image. The generated script is Adobe Photoshop compliant (which is largely used in image forensics analysis) thus permitting the replication of the enhancement steps. Experiments on a dataset of images are also reported showing the effectiveness of the proposed methodology.

Personal photograph enhancement using internet photo collections.

PubMed

Zhang, Chenxi; Gao, Jizhou; Wang, Oliver; Georgel, Pierre; Yang, Ruigang; Davis, James; Frahm, Jan-Michael; Pollefeys, Marc

2014-02-01

Given the growth of Internet photo collections, we now have a visual index of all major cities and tourist sites in the world. However, it is still a difficult task to capture that perfect shot with your own camera when visiting these places, especially when your camera itself has limitations, such as a limited field of view. In this paper, we propose a framework to overcome the imperfections of personal photographs of tourist sites using the rich information provided by large-scale Internet photo collections. Our method deploys state-of-the-art techniques for constructing initial 3D models from photo collections. The same techniques are then used to register personal photographs to these models, allowing us to augment personal 2D images with 3D information. This strong available scene prior allows us to address a number of traditionally challenging image enhancement techniques and achieve high-quality results using simple and robust algorithms. Specifically, we demonstrate automatic foreground segmentation, mono-to-stereo conversion, field-of-view expansion, photometric enhancement, and additionally automatic annotation with geolocation and tags. Our method clearly demonstrates some possible benefits of employing the rich information contained in online photo databases to efficiently enhance and augment one's own personal photographs.

Dielectrophoretic positioning of single nanoparticles on atomic force microscope tips for tip-enhanced Raman spectroscopy.

PubMed

Leiterer, Christian; Deckert-Gaudig, Tanja; Singh, Prabha; Wirth, Janina; Deckert, Volker; Fritzsche, Wolfgang

2015-05-01

Tip-enhanced Raman spectroscopy, a combination of Raman spectroscopy and scanning probe microscopy, is a powerful technique to detect the vibrational fingerprint of molecules at the nanometer scale. A metal nanoparticle at the apex of an atomic force microscope tip leads to a large enhancement of the electromagnetic field when illuminated with an appropriate wavelength, resulting in an increased Raman signal. A controlled positioning of individual nanoparticles at the tip would improve the reproducibility of the probes and is quite demanding due to usually serial and labor-intensive approaches. In contrast to commonly used submicron manipulation techniques, dielectrophoresis allows a parallel and scalable production, and provides a novel approach toward reproducible and at the same time affordable tip-enhanced Raman spectroscopy tips. We demonstrate the successful positioning of an individual plasmonic nanoparticle on a commercial atomic force microscope tip by dielectrophoresis followed by experimental proof of the Raman signal enhancing capabilities of such tips. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluation of aircraft microwave data for locating zones for well stimulation and enhanced gas recovery. [Arkansas Arkoma Basin

NASA Technical Reports Server (NTRS)

Macdonald, H.; Waite, W.; Elachi, C.; Babcock, R.; Konig, R.; Gattis, J.; Borengasser, M.; Tolman, D.

1980-01-01

Imaging radar was evaluated as an adjunct to conventional petroleum exploration techniques, especially linear mapping. Linear features were mapped from several remote sensor data sources including stereo photography, enhanced LANDSAT imagery, SLAR radar imagery, enhanced SAR radar imagery, and SAR radar/LANDSAT combinations. Linear feature maps were compared with surface joint data, subsurface and geophysical data, and gas production in the Arkansas part of the Arkoma basin. The best LANDSAT enhanced product for linear detection was found to be a winter scene, band 7, uniform distribution stretch. Of the individual SAR data products, the VH (cross polarized) SAR radar mosaic provides for detection of most linears; however, none of the SAR enhancements is significantly better than the others. Radar/LANDSAT merges may provide better linear detection than a single sensor mapping mode, but because of operator variability, the results are inconclusive. Radar/LANDSAT combinations appear promising as an optimum linear mapping technique, if the advantages and disadvantages of each remote sensor are considered.

Chemical Enhancements to Pump-and-Treat Remediation

EPA Pesticide Factsheets

The intent of this document is to explore the use of chemical enhancement to improve groundwater remediation efficiencies using pump-and-treat technologies, and point out arenas of contamination where such techniques are not practical.

Liquigroud technique: a new concept for enhancing dissolution rate of glibenclamide by combination of liquisolid and co-grinding technologies.

PubMed

Azharshekoufeh, Leila; Shokri, Javad; Barzegar-Jalali, Mohammad; Javadzadeh, Yousef

2017-01-01

Introduction: The potential of combining liquisolid and co-grinding technologies (liquiground technique) was investigated to improve the dissolution rate of a water-insoluble agent (glibenclamide) with formulation-dependent bioavailability. Methods: To this end, different formulations of liquisolid tablets with a wide variety of non-volatile solvents contained varied ratios of drug: solvent and dissimilar carriers were prepared, and then their release profiles were evaluated. Furthermore, the effect of size reduction by ball milling on the dissolution behavior of glibenclamide from liquisolid tablets was investigated. Any interaction between the drug and the excipient or crystallinity changes during formulation procedure was also examined using X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results: The present study revealed that classic liquisolid technique did not significantly affect the drug dissolution profile as compared to the conventional tablets. Size reduction obtained by co-grinding of liquid medication was more effective than the implementation of liquisolid technique in enhancing the dissolution rate of glibenclamide. The XRD and DSC data displayed no formation of complex or any crystallinity changes in both formulations. Conclusion: An enhanced dissolution rate of glibenclamide is achievable through the combination of liquisolid and co-grinding technologies.

Arterial Wall Imaging in Pediatric Stroke.

PubMed

Dlamini, Nomazulu; Yau, Ivanna; Muthusami, Prakash; Mikulis, David J; Elbers, Jorina; Slim, Mahmoud; Askalan, Rand; MacGregor, Daune; deVeber, Gabrielle; Shroff, Manohar; Moharir, Mahendranath

2018-04-01

Arteriopathy is common in childhood arterial ischemic stroke (AIS) and predicts stroke recurrence. Currently available vascular imaging techniques mainly image the arterial lumen rather than the vessel wall and have a limited ability to differentiate among common arteriopathies. We aimed to investigate the value of a magnetic resonance imaging-based technique, namely noninvasive arterial wall imaging (AWI), for distinguishing among arteriopathy subtypes in a consecutive cohort of children presenting with AIS. Children with confirmed AIS and magnetic resonance angiography underwent 3-Tesla AWI including T1-weighted 2-dimensional fluid-attenuated inversion recovery fast spin echo sequences pre- and post-gadolinium contrast. AWI characteristics, including wall enhancement, wall thickening, and luminal stenosis, were documented for all. Twenty-six children with AIS had AWI. Of these, 9 (35%) had AWI enhancement. AWI enhancement was associated with anterior circulation magnetic resonance angiography abnormality and cortical infarction in 8 of 9 (89%) children and normal magnetic resonance angiography with posterior circulation subcortical infarction in 1 (1 of 9; 11%) child. AWI enhancement was not seen in 17 (65%), 10 (59%) of whom had an abnormal magnetic resonance angiography. Distinct patterns of pre- and postcontrast signal abnormality were demonstrated in the vessel wall in the region of interest in children with transient cerebral arteriopathy, arterial dissection, primary central nervous system angiitis, dissecting aneurysm, and cardioembolic stroke. AWI is a noninvasive, high-resolution magnetic resonance AWI technique, which can be successfully used in children presenting with AIS. Patterns of AWI enhancement are recognizable and associated with specific AIS pathogeneses. Further studies are required to assess the additional diagnostic utility of AWI over routine vascular imaging techniques, in childhood AIS. © 2018 American Heart Association, Inc.

Blob-enhanced reconstruction technique

NASA Astrophysics Data System (ADS)

Castrillo, Giusy; Cafiero, Gioacchino; Discetti, Stefano; Astarita, Tommaso

2016-09-01

A method to enhance the quality of the tomographic reconstruction and, consequently, the 3D velocity measurement accuracy, is presented. The technique is based on integrating information on the objects to be reconstructed within the algebraic reconstruction process. A first guess intensity distribution is produced with a standard algebraic method, then the distribution is rebuilt as a sum of Gaussian blobs, based on location, intensity and size of agglomerates of light intensity surrounding local maxima. The blobs substitution regularizes the particle shape allowing a reduction of the particles discretization errors and of their elongation in the depth direction. The performances of the blob-enhanced reconstruction technique (BERT) are assessed with a 3D synthetic experiment. The results have been compared with those obtained by applying the standard camera simultaneous multiplicative reconstruction technique (CSMART) to the same volume. Several blob-enhanced reconstruction processes, both substituting the blobs at the end of the CSMART algorithm and during the iterations (i.e. using the blob-enhanced reconstruction as predictor for the following iterations), have been tested. The results confirm the enhancement in the velocity measurements accuracy, demonstrating a reduction of the bias error due to the ghost particles. The improvement is more remarkable at the largest tested seeding densities. Additionally, using the blobs distributions as a predictor enables further improvement of the convergence of the reconstruction algorithm, with the improvement being more considerable when substituting the blobs more than once during the process. The BERT process is also applied to multi resolution (MR) CSMART reconstructions, permitting simultaneously to achieve remarkable improvements in the flow field measurements and to benefit from the reduction in computational time due to the MR approach. Finally, BERT is also tested on experimental data, obtaining an increase of the signal-to-noise ratio in the reconstructed flow field and a higher value of the correlation factor in the velocity measurements with respect to the volume to which the particles are not replaced.

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

PubMed Central

2014-01-01

Summary Vibrational transitions contain some of the richest fingerprints of molecules and materials, providing considerable physicochemical information. Vibrational transitions can be characterized by different spectroscopies, and alternatively by several imaging techniques enabling to reach sub-microscopic spatial resolution. In a quest to always push forward the detection limit and to lower the number of needed vibrational oscillators to get a reliable signal or imaging contrast, surface plasmon resonances (SPR) are extensively used to increase the local field close to the oscillators. Another approach is based on maximizing the collective response of the excited vibrational oscillators through molecular coherence. Both features are often naturally combined in vibrational nonlinear optical techniques. In this frame, this paper reviews the main achievements of the two most common vibrational nonlinear optical spectroscopies, namely surface-enhanced sum-frequency generation (SE-SFG) and surface-enhanced coherent anti-Stokes Raman scattering (SE-CARS). They can be considered as the nonlinear counterpart and/or combination of the linear surface-enhanced infrared absorption (SEIRA) and surface-enhanced Raman scattering (SERS) techniques, respectively, which are themselves a branching of the conventional IR and spontaneous Raman spectroscopies. Compared to their linear equivalent, those nonlinear vibrational spectroscopies have proved to reach higher sensitivity down to the single molecule level, opening the way to astonishing perspectives for molecular analysis. PMID:25551056

Enhanced degradation of spiro-insecticides and their leacher enol derivatives in soil by solarization and biosolarization techniques.

PubMed

Fenoll, José; Garrido, Isabel; Vela, Nuria; Ros, Caridad; Navarro, Simón

2017-04-01

The leaching potential of three insecticides (spirodiclofen, spiromesifen, and spirotetramat) was assessed using disturbed soil columns. Small quantities of spirodiclofen and spiromesifen were detected in leachate fraction, while spirotetramat residues were not found in the leachates. In addition, the transformation products (enol derivatives) are relatively more mobile than the parent compounds and may leach into groundwater. Moreover, the use of disinfection soil techniques (solarization and biosolarization) to enhance their degradation rates in soil was investigated. The results show that both practices achieved a reduction in the number of juvenile nematodes, enhancing in a parallel way degradation rates of the insecticides and their enol derivatives as compared with the non-disinfected soil. This behavior can be mainly attributed to the increase in soil temperature and changes in microbial activity. All insecticides showed similar behavior under solarization and biosolarization conditions. As a consequence, both agronomic techniques could be considered as suitable strategies for detoxification of soils polluted with the studied pesticides.

Generalized image contrast enhancement technique based on Heinemann contrast discrimination model

NASA Astrophysics Data System (ADS)

Liu, Hong; Nodine, Calvin F.

1994-03-01

This paper presents a generalized image contrast enhancement technique which equalizes perceived brightness based on the Heinemann contrast discrimination model. This is a modified algorithm which presents an improvement over the previous study by Mokrane in its mathematically proven existence of a unique solution and in its easily tunable parameterization. The model uses a log-log representation of contrast luminosity between targets and the surround in a fixed luminosity background setting. The algorithm consists of two nonlinear gray-scale mapping functions which have seven parameters, two of which are adjustable Heinemann constants. Another parameter is the background gray level. The remaining four parameters are nonlinear functions of gray scale distribution of the image, and can be uniquely determined once the previous three are given. Tests have been carried out to examine the effectiveness of the algorithm for increasing the overall contrast of images. It can be demonstrated that the generalized algorithm provides better contrast enhancement than histogram equalization. In fact, the histogram equalization technique is a special case of the proposed mapping.

Improving compliance in remote healthcare systems through smartphone battery optimization.

PubMed

Alshurafa, Nabil; Eastwood, Jo-Ann; Nyamathi, Suneil; Liu, Jason J; Xu, Wenyao; Ghasemzadeh, Hassan; Pourhomayoun, Mohammad; Sarrafzadeh, Majid

2015-01-01

Remote health monitoring (RHM) has emerged as a solution to help reduce the cost burden of unhealthy lifestyles and aging populations. Enhancing compliance to prescribed medical regimens is an essential challenge to many systems, even those using smartphone technology. In this paper, we provide a technique to improve smartphone battery consumption and examine the effects of smartphone battery lifetime on compliance, in an attempt to enhance users' adherence to remote monitoring systems. We deploy WANDA-CVD, an RHM system for patients at risk of cardiovascular disease (CVD), using a wearable smartphone for detection of physical activity. We tested the battery optimization technique in an in-lab pilot study and validated its effects on compliance in the Women's Heart Health Study. The battery optimization technique enhanced the battery lifetime by 192% on average, resulting in a 53% increase in compliance in the study. A system like WANDA-CVD can help increase smartphone battery lifetime for RHM systems monitoring physical activity.

Analytical methods in multivariate highway safety exposure data estimation

DOT National Transportation Integrated Search

1984-01-01

Three general analytical techniques which may be of use in : extending, enhancing, and combining highway accident exposure data are : discussed. The techniques are log-linear modelling, iterative propor : tional fitting and the expectation maximizati...

Using the Delphi Technique to Support Curriculum Development

ERIC Educational Resources Information Center

Sitlington, Helen Barbara; Coetzer, Alan John

2015-01-01

Purpose: The purpose of this paper is to present an analysis of the use of the Delphi technique to support curriculum development with a view to enhancing existing literature on use of the technique for renewal of business course curricula. Design/methodology/approach: The authors outline the Delphi process for obtaining consensus amongst a…

Multibeam satellite EIRP adaptability for aeronautical communications.

NASA Technical Reports Server (NTRS)

Kinal, G. V.; Bisaga, J. J.

1973-01-01

EIRP enhancement and management techniques, emphasizing aeronautical communications and adaptable multibeam concepts, are classified and characterized. User requirement and demand characteristics that exploit the improvement available from each technique are identified, and the relative performance improvement of each is discussed. It is concluded that aeronautical satellite communications could benefit greatly by the employment of these techniques.

Increased-resolution OCT thickness mapping of the human macula: a statistically based registration.

PubMed

Bernardes, Rui; Santos, Torcato; Cunha-Vaz, José

2008-05-01

To describe the development of a technique that enhances spatial resolution of retinal thickness maps of the Stratus OCT (Carl Zeiss Meditec, Inc., Dublin, CA). A retinal thickness atlas (RT-atlas) template was calculated, and a macular coordinate system was established, to pursue this objective. The RT-atlas was developed from principal component analysis of retinal thickness analyzer (RTA) maps acquired from healthy volunteers. The Stratus OCT radial thickness measurements were registered on the RT-atlas, from which an improved macular thickness map was calculated. Thereafter, Stratus OCT circular scans were registered on the previously calculated map to enhance spatial resolution. The developed technique was applied to Stratus OCT thickness data from healthy volunteers and from patients with diabetic retinopathy (DR) or age-related macular degeneration (AMD). Results showed that for normal, or close to normal, macular thickness maps from healthy volunteers and patients with DR, this technique can be an important aid in determining retinal thickness. Efforts are under way to improve the registration of retinal thickness data in patients with AMD. The developed technique enhances the evaluation of data acquired by the Stratus OCT, helping the detection of early retinal thickness abnormalities. Moreover, a normative database of retinal thickness measurements gained from this technique, as referenced to the macular coordinate system, can be created without errors induced by missed fixation and eye tilt.

Investigation of MR scanning, image registration, and image processing techniques to visualize cortical veins for neurosurgery

NASA Astrophysics Data System (ADS)

Noordmans, Herke J.; Rutten, G. J. M.; Willems, Peter W. A.; Hoogduin, J.; Viergever, Max A.

2001-01-01

The visualization of brain vessels on the cortex helps the neurosurgeon in two ways: To avoid blood vessels when specifying the trepanation entry, and to overcome errors in the surgical navigation system due to brain shift. We compared 3D T1 MR, 3D T1 MR with gadolinium contrast, MR venography and MR phase contrast angiography as scanning techniques, mutual information as registration technique, and thresholding and multi-vessel enhancement as image processing techniques. We evaluated the volume rendered results based on their quality and correspondence with photos took during surgery. It appears that with 3D T1 MR scans, gadolinium is required to show cortical veins. The visibility of small cortical veins is strongly enhanced by subtracting a 3D T1 MR baseline scan, which should be registered to the scan with gadolinium contrast, even when the scans are made during the same session. Multi-vessel enhancement helps to clarify the view on small vessels by reducing the noise level, but strikingly does not reveal more. MR venography does show intracerebral veins with high detail, but is, as is, unsuited to show cortical veins due to the low contrast with CSF. MR phase contrast angiography can perform equally well as the subtraction technique, but its quality seems to show more inter-patient variability.

Enhanced Multiobjective Optimization Technique for Comprehensive Aerospace Design. Part A

NASA Technical Reports Server (NTRS)

Chattopadhyay, Aditi; Rajadas, John N.

1997-01-01

A multidisciplinary design optimization procedure which couples formal multiobjectives based techniques and complex analysis procedures (such as computational fluid dynamics (CFD) codes) developed. The procedure has been demonstrated on a specific high speed flow application involving aerodynamics and acoustics (sonic boom minimization). In order to account for multiple design objectives arising from complex performance requirements, multiobjective formulation techniques are used to formulate the optimization problem. Techniques to enhance the existing Kreisselmeier-Steinhauser (K-S) function multiobjective formulation approach have been developed. The K-S function procedure used in the proposed work transforms a constrained multiple objective functions problem into an unconstrained problem which then is solved using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. Weight factors are introduced during the transformation process to each objective function. This enhanced procedure will provide the designer the capability to emphasize specific design objectives during the optimization process. The demonstration of the procedure utilizes a computational Fluid dynamics (CFD) code which solves the three-dimensional parabolized Navier-Stokes (PNS) equations for the flow field along with an appropriate sonic boom evaluation procedure thus introducing both aerodynamic performance as well as sonic boom as the design objectives to be optimized simultaneously. Sensitivity analysis is performed using a discrete differentiation approach. An approximation technique has been used within the optimizer to improve the overall computational efficiency of the procedure in order to make it suitable for design applications in an industrial setting.

Enlargement and sculpturing of a small and deformed glans.

PubMed

Perovic, Savra; Radojicic, Zoran I; Djordjevic, Miroslav Lj; Vukadinovic, Vojkan V

2003-10-01

We present 2 techniques of enhancement and sculpturing of a small and/or deformed glans. The small glans in primary or re-do hypospadias repair was enhanced by longitudinal double-faced island flaps incorporated onto the ventral side of the glans between the glans wings. The deformed glans, of small or normal size (with normal urethra or well functioning neourethra), was enlarged and sculptured by injection of hydrogel. Between May 1997 and March 2002, 27 patients underwent glans enhancement and sculpturing. Small deformed glans occurred after failed hypospadias repair in 10 patients, penile trauma in 3, hemangioma sclerozation in 2, primary hypospadias in 8 and normally developed penile body in 4. A double-faced island flap was performed in 14 patients, glans was enhanced by hydrogel injection in 9 and both procedures were performed in 4. Mean followup was 34 months for the double-faced flap technique 17 months for hydrogel injection. Satisfactory enlargement and esthetic appearance were achieved in 13 of the 14 patients who underwent the double-faced flap technique and 1 required surgical correction. Of the 9 patients who underwent either single or multistage hydrogel injection 8 had good results and 1 required partial removal of hydrogel after hypercorrection. The combination of these 2 techniques provided satisfactory results in all 4 cases. Enlargement and sculpturing of a small deformed glans are challenging and difficult. A double-faced island flap and/or injection of hydrogel resolves this problem satisfactorily.

Enhancement of Fluorescence-Based Sandwich Immunoassay Using Multilayered Microplates Modified with Plasma-Polymerized Films

PubMed Central

Yano, Kazuyoshi; Iwasaki, Akira

2016-01-01

A functional modification of the surface of a 96-well microplate coupled with a thin layer deposition technique is demonstrated for enhanced fluorescence-based sandwich immunoassays. The plasma polymerization technique enabling the deposition of organic thin films was employed for the modification of the well surface of a microplate. A silver layer and a plasma-polymerized film were consecutively deposited on the microplate as a metal mirror and the optical interference layer, respectively. When Cy3-labeled antibody was applied to the wells of the resulting multilayered microplate without any immobilization step, greatly enhanced fluorescence was observed compared with that obtained with the unmodified one. The same effect could be also exhibited for an immunoassay targeting antigen directly adsorbed on the multilayered microplate. Furthermore, a sandwich immunoassay for the detection of interleukin 2 (IL-2) was performed with the multilayered microplates, resulting in specific and 88-fold–enhanced fluorescence detection. PMID:28029144

Optimizing laser crater enhanced Raman scattering spectroscopy

NASA Astrophysics Data System (ADS)

Lednev, V. N.; Sdvizhenskii, P. A.; Grishin, M. Ya.; Fedorov, A. N.; Khokhlova, O. V.; Oshurko, V. B.; Pershin, S. M.

2018-05-01

The laser crater enhanced Raman scattering (LCERS) spectroscopy technique has been systematically studied for chosen sampling strategy and influence of powder material properties on spectra intensity enhancement. The same nanosecond pulsed solid state Nd:YAG laser (532 nm, 10 ns, 0.1-1.5 mJ/pulse) was used for laser crater production and Raman scattering experiments for L-aspartic acid powder. Increased sampling area inside crater cavity is the key factor for Raman signal improvement for the LCERS technique, thus Raman signal enhancement was studied as a function of numerous experimental parameters including lens-to-sample distance, wavelength (532 and 1064 nm) and laser pulse energy utilized for crater production. Combining laser pulses of 1064 and 532 nm wavelengths for crater ablation was shown to be an effective way for additional LCERS signal improvement. Powder material properties (particle size distribution, powder compactness) were demonstrated to affect LCERS measurements with better results achieved for smaller particles and lower compactness.

Tip-enhanced Raman mapping with top-illumination AFM.

PubMed

Chan, K L Andrew; Kazarian, Sergei G

2011-04-29

Tip-enhanced Raman mapping is a powerful, emerging technique that offers rich chemical information and high spatial resolution. Currently, most of the successes in tip-enhanced Raman scattering (TERS) measurements are based on the inverted configuration where tips and laser are approaching the sample from opposite sides. This results in the limitation of measurement for transparent samples only. Several approaches have been developed to obtain tip-enhanced Raman mapping in reflection mode, many of which involve certain customisations of the system. We have demonstrated in this work that it is also possible to obtain TERS nano-images using an upright microscope (top-illumination) with a gold-coated Si atomic force microscope (AFM) cantilever without significant modification to the existing integrated AFM/Raman system. A TERS image of a single-walled carbon nanotube has been achieved with a spatial resolution of ∼ 20-50 nm, demonstrating the potential of this technique for studying non-transparent nanoscale materials.

Evidence based review of the impact of image enhanced endoscopy in the diagnosis of gastric disorders

PubMed Central

Hussain, Ikram; Ang, Tiing Leong

2016-01-01

Gastric cancer is the third most common cause of cancer-related death. Advanced stages of gastric cancers generally have grim prognosis. But, good prognosis can be achieved if such cancers are detected, diagnosed and resected at early stages. However, early gastric cancers and its precursors often produce only subtle mucosal changes and therefore quite commonly remain elusive at the conventional examination with white light endoscopy. Image-enhanced endoscopy makes mucosal lesions more conspicuous and can therefore potentially yield earlier and more accurate diagnoses. Recent years have seen growing work of research in support of various types of image enhanced endoscopy (IEE) techniques (e.g., dye-chromoendoscopy; magnification endoscopy; narrow-band imaging; flexible spectral imaging color enhancement; and I-SCAN) for a variety of gastric pathologies. In this review, we will examine the evidence for the utilization of various IEE techniques in the diagnosis of gastric disorders. PMID:28042388

Using a Strategy of "Structured Conversation" to Enhance the Quality of Tutorial Time

ERIC Educational Resources Information Center

Robinson, Stephanie

2008-01-01

This article considers the impact of a technique of structured conversation to enhance a student-centred approach to tutorial time. It is suggested that the development of such an approach can provide enhanced learning support in the current challenge of widening diversity in the learner population. Many students in modern tertiary education show…

EFSUMB guidelines 2011: comment on emergent indications and visions.

PubMed

Dietrich, C F; Cui, X W; Barreiros, A P; Hocke, M; Ignee, A

2012-07-01

The focus of this article is the emergent and potential indications of contrast-enhanced ultrasound (CEUS). Emergent applications of CEUS techniques include extravascular and intracavitary contrast-enhanced ultrasound, quantitative assessment of microvascular circulation for tumor response assessment, and tumor characterization using dynamic contrast-enhanced ultrasound (DCE-US). Potential indications for microbubble agents include novel molecular imaging and drug and gene delivery techniques, which have been successfully tested in animal models. "Comments and Illustrations of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Non-Liver Guidelines 2011" which focus more on established applications are published in the same supplement to Ultraschall in der Medizin (European Journal of Ultrasound). © Georg Thieme Verlag KG Stuttgart · New York.

Hydroponic Culture

ERIC Educational Resources Information Center

Steucek, G. L.; Yurkiewicz, W. J.

1973-01-01

Describes a hydroponic culture technique suitable for student exercises in biology. This technique of growing plants in nutrient solutions enhances plant growth, and is an excellent way to obtain intact plants with root systems free of soil or other particulate matter. (JR)

Clustering: An Interactive Technique to Enhance Learning in Biology.

ERIC Educational Resources Information Center

Ambron, Joanna

1988-01-01

Explains an interdisciplinary approach to biology and writing which increases students' mastery of vocabulary, scientific concepts, creativity, and expression. Describes modifications of the clustering technique used to summarize lectures, integrate reading and understand textbook material. (RT)

Enhanced ultrasonic inspection of steel bridge pin components.

DOT National Transportation Integrated Search

1998-01-01

This report describes the development of a technique for obtaining a reliable assessment of the condition of steel bridge pins already determined by ultrasound to contain imperfections. The details of a technique for performing high-definition ultras...

Systems-Level Synthetic Biology for Advanced Biofuel Production

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

Ruffing, Anne; Jensen, Travis J.; Strickland, Lucas Marshall

2015-03-01

Cyanobacteria have been shown to be capable of producing a variety of advanced biofuels; however, product yields remain well below those necessary for large scale production. New genetic tools and high throughput metabolic engineering techniques are needed to optimize cyanobacterial metabolisms for enhanced biofuel production. Towards this goal, this project advances the development of a multiple promoter replacement technique for systems-level optimization of gene expression in a model cyanobacterial host: Synechococcus sp. PCC 7002. To realize this multiple-target approach, key capabilities were developed, including a high throughput detection method for advanced biofuels, enhanced transformation efficiency, and genetic tools for Synechococcusmore » sp. PCC 7002. Moreover, several additional obstacles were identified for realization of this multiple promoter replacement technique. The techniques and tools developed in this project will help to enable future efforts in the advancement of cyanobacterial biofuels.« less

Recent progress in tissue optical clearing

PubMed Central

Zhu, Dan; Larin, Kirill V; Luo, Qingming; Tuchin, Valery V

2013-01-01

Tissue optical clearing technique provides a prospective solution for the application of advanced optical methods in life sciences. This paper gives a review of recent developments in tissue optical clearing techniques. The physical, molecular and physiological mechanisms of tissue optical clearing are overviewed and discussed. Various methods for enhancing penetration of optical-clearing agents into tissue, such as physical methods, chemical-penetration enhancers and combination of physical and chemical methods are introduced. Combining the tissue optical clearing technique with advanced microscopy image or labeling technique, applications for 3D microstructure of whole tissues such as brain and central nervous system with unprecedented resolution are demonstrated. Moreover, the difference in diffusion and/or clearing ability of selected agents in healthy versus pathological tissues can provide a highly sensitive indicator of the tissue health/pathology condition. Finally, recent advances in optical clearing of soft or hard tissue for in vivo imaging and phototherapy are introduced. PMID:24348874

A manual for inexpensive methods of analyzing and utilizing remote sensor data

NASA Technical Reports Server (NTRS)

Elifrits, C. D.; Barr, D. J.

1978-01-01

Instructions are provided for inexpensive methods of using remote sensor data to assist in the completion of the need to observe the earth's surface. When possible, relative costs were included. Equipment need for analysis of remote sensor data is described, and methods of use of these equipment items are included, as well as advantages and disadvantages of the use of individual items. Interpretation and analysis of stereo photos and the interpretation of typical patterns such as tone and texture, landcover, drainage, and erosional form are described. Similar treatment is given to monoscopic image interpretation, including LANDSAT MSS data. Enhancement techniques are detailed with respect to their application and simple techniques of creating an enhanced data item. Techniques described include additive and subtractive (Diazo processes) color techniques and enlargement of photos or images. Applications of these processes, including mappings of land resources, engineering soils, geology, water resources, environmental conditions, and crops and/or vegetation, are outlined.

A study of J-coupling spectroscopy using the Earth's field nuclear magnetic resonance inside a laboratory.

PubMed

Liao, Shu-Hsien; Chen, Ming-Jye; Yang, Hong-Chang; Lee, Shin-Yi; Chen, Hsin-Hsien; Horng, Herng-Er; Yang, Shieh-Yueh

2010-10-01

In this paper, an instrumentation of the Earth's field nuclear magnetic resonance (EFNMR) inside a laboratory is presented. A lock-in analysis (LIA) technique was proposed to enhance the signal-to-noise ratio (SNR). A SNR of 137.8 was achieved in a single measurement for 9 ml tap water, and the LIA technique significantly enhanced the SNR to 188 after a 10-average in a noisy laboratory environment. The proton-phosphorus coupling in trimethyl phosphate ((CH(3)O)(3)PO) with J-coupling J[H,F]=(10.99±0.013) Hz has been demonstrated. The LIA technique improves the SNR, and a 2.6-fold improvement in SNR over that of the frequency-adjusted averaging is achieved. To reduce the noise in EFNMR, it was suggested that the LIA technique and the first order gradient shim be used to achieve a subhertz linewidth.

Contrast enhancement of transparencies

NASA Technical Reports Server (NTRS)

Shulman, A. R.; Lee, S. H.

1976-01-01

System can enhance or reduce contrast of photographic transparency for printing or projection by using constructive and destructive interference of collimated laser beam. System is potentially less expensive than electronic CRT methods and is more accurate than trial-and-error manual techniques.

Guidelines for Enhancement of Visual Conspicuity of Trains at Grade Crossings

DOT National Transportation Integrated Search

1975-05-01

This report summarizes a comprehensive study of potential means of reducing the probability of train-motor vehicle collisions at railroad-highway grade crossings through enhancement of the visual conspicuity of locomotives. Passive techniques are rev...

Transmission and storage of medical images with patient information.

PubMed

Acharya U, Rajendra; Subbanna Bhat, P; Kumar, Sathish; Min, Lim Choo

2003-07-01

Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images, to reduce storage and transmission overheads. The text data is encrypted before interleaving with images to ensure greater security. The graphical signals are interleaved with the image. Two types of error control-coding techniques are proposed to enhance reliability of transmission and storage of medical images interleaved with patient information. Transmission and storage scenarios are simulated with and without error control coding and a qualitative as well as quantitative interpretation of the reliability enhancement resulting from the use of various commonly used error control codes such as repetitive, and (7,4) Hamming code is provided.

Hyperpolarized NMR: d-DNP, PHIP, and SABRE.

PubMed

Kovtunov, Kirill Viktorovich; Pokochueva, Ekaterina; Salnikov, Oleg; Cousin, Samuel; Kurzbach, Dennis; Vuichoud, Basile; Jannin, Sami; Chekmenev, Eduard; Goodson, Boyd; Barskiy, Danila; Koptyug, Igor

2018-05-23

NMR signals intensities can be enhanced by several orders of magnitude via utilization of techniques for hyperpolarization of different molecules, and it allows one to overcome the main sensitivity challenge of modern NMR/MRI techniques. Hyperpolarized fluids can be successfully used in different applications of material science and biomedicine. This focus review covers the fundamentals of the preparation of hyperpolarized liquids and gases via dissolution dynamic nuclear polarization (d-DNP) and parahydrogen-based techniques such as signal amplification by reversible exchange (SABRE) and parahydrogen-induced polarization (PHIP) in both heterogeneous and homogeneous processes. The different novel aspects of hyperpolarized fluids formation and utilization along with the possibility of NMR signal enhancement observation are described. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Plasma deposition and surface modification techniques for wear resistance

NASA Technical Reports Server (NTRS)

Spalvins, T.

1982-01-01

The ion-assisted or plasma coating technology is discussed as it applies to the deposition of hard, wear resistant refractory compound films. Of the many sputtering and ion plating modes and configurations the reactive magnetron sputtering and the reactive triode ion plating techniques are the preferred ones to deposit wear resistant coatings for tribological applications. Both of these techniques incorporate additional means to enhance the ionization efficiency and chemical reaction to precision tailor desirable tribological characteristics. Interrelationships between film formation, structure, and ribological properties are strictly controlled by the deposition parameters and the substrate condition. The enhanced ionization contributes to the excellent adherence and coherence, reduced internal stresses and improved structural growth to form dense, cohesive, equiaxed grain structure for improved wear resistance and control.

Niobium pentoxide: a promising surface-enhanced Raman scattering active semiconductor substrate

NASA Astrophysics Data System (ADS)

Shan, Yufeng; Zheng, Zhihui; Liu, Jianjun; Yang, Yong; Li, Zhiyuan; Huang, Zhengren; Jiang, Dongliang

2017-03-01

Surface-enhanced Raman scattering technique, as a powerful tool to identify the molecular species, has been severely restricted to the noble metals. The surface-enhanced Raman scattering substrates based on semiconductors would overcome the shortcomings of metal substrates and promote development of surface-enhanced Raman scattering technique in surface science, spectroscopy, and biomedicine studies. However, the detection sensitivity and enhancement effects of semiconductor substrates are suffering from their weak activities. In this work, a semiconductor based on Nb2O5 is reported as a new candidate for highly sensitive surface-enhanced Raman scattering detection of dye molecules. The largest enhancement factor value greater than 107 was observed with the laser excitation at 633 and 780 nm for methylene blue detection. As far as literature review shows, this is in the rank of the highest sensitivity among semiconductor materials; even comparable to the metal nanostructure substrates with "hot spots". The impressive surface-enhanced Raman scattering activities can be attributed to the chemical enhancement dominated by the photo-induced charge transfer, as well as the electromagnetic enhancement, which have been supported by the density-functional-theory and finite element method calculation results. The chemisorption of dye on Nb2O5 creates a new highest occupied molecular orbital and lowest unoccupied molecular orbital contributed by both fragments in the molecule-Nb2O5 system, which makes the charge transfer more feasible with longer excitation wavelength. In addition, the electromagnetic enhancement mechanism also accounts for two orders of magnitude enhancement in the overall enhancement factor value. This work has revealed Nb2O5 nanoparticles as a new semiconductor surface-enhanced Raman scattering substrate that is able to replace noble metals and shows great potentials applied in the fields of biology related.

A technique for enhancing and matching the resolution of microwave measurements from the SSM/I instrument

NASA Technical Reports Server (NTRS)

Robinson, Wayne D.; Kummerrow, Christian; Olson, William S.

1992-01-01

A correction technique is presented for matching the resolution of all the frequencies of the satelliteborne Special Sensor Microwave/Imager (SSM/I) to the about-25-km spatial resolution of the 37-GHz channel. This entails, on the one hand, the enhancement of the spatial resolution of the 19- and 22-GHz channels, and on the other, the degrading of that of the 85-GHz channel. The Backus and Gilbert (1970) approach is found to yield sufficient spatial resolution to render such a correction worthwhile.

Remote sensing of land-based voids using computer enhanced infrared thermography

NASA Astrophysics Data System (ADS)

Weil, Gary J.

1989-10-01

Experiments are described in which computer-enhanced infrared thermography techniques are used to detect and describe subsurface land-based voids, such as voids surrounding buried utility pipes, voids in concrete structures such as airport taxiways, abandoned buried utility storage tanks, and caves and underground shelters. Infrared thermography also helps to evaluate bridge deck systems, highway pavements, and garage concrete. The IR thermography techniques make it possible to survey large areas quickly and efficiently. The paper also surveys the advantages and limitations of thermographic testing in comparison with other forms of NDT.

Method of Stamping Surface-Enhance Raman Spectroscopy for Label-Free, Multiplexed, Molecular Sensing and Imaging

NASA Technical Reports Server (NTRS)

Shih, Wei-Chuan (Inventor)

2017-01-01

The present disclosure relates the use of a stamping surface enhanced Raman scattering (S-SERS) technique with nanoporous gold disk (NPGD) plasmonic substrates to produce a label-free, multiplexed molecular sensing and imaging technique. A NPGD SERS substrate is stamped onto a surface containing one or more target molecules, followed by SERS measurement of the target molecules located between the surface and SERS substrate. The target molecules may be deposited on the surface, which may be a carrier substrate such as polydimethylsiloxane (PDMS).

Water immersion in neonatal bereavement photography.

PubMed

Duffey, Heather

2014-01-01

Water immersion in neonatal bereavement photography is a new technique intended to enhance the quality of the photographs provided to families following their loss. Water immersion appears to be most helpful following a second trimester fetal demise. This technique can be used by nurses, professional photographers and others in addition to more traditional neonatal bereavement photography. It does not require special skills or equipment and can be implemented in virtually any perinatal setting. The enhanced quality of photographs produced with this method can potentially provide a source of comfort to grieving families. © 2014 AWHONN.

Optical design applications for enhanced illumination performance

NASA Astrophysics Data System (ADS)

Gilray, Carl; Lewin, Ian

1995-08-01

Nonimaging optical design techniques have been applied in the illumination industry for many years. Recently however, powerful software has been developed which allows accurate simulation and optimization of illumination devices. Wide experience has been obtained in using such design techniques for practical situations. These include automotive lighting where safety is of greatest importance, commercial lighting systems designed for energy efficiency, and numerous specialized applications. This presentation will discuss the performance requirements of a variety of illumination devices. It will further cover design methodology and present a variety of examples of practical applications for enhanced system performance.

Semiochemical mediated enhancement of males to complement sterile insect technique in management of the tephritid pest Bactrocera tryoni (Froggatt)

USDA-ARS?s Scientific Manuscript database

Queensland fruit fly, Bactrocera tryoni (Froggatt), is the most significant pest of Australia’s $9 billion horticulture industry. The sterile insect technique (SIT) and male annihilation technique (MAT) based on traps baited with a synthetic analogue of raspberry ketone (RK) are two of the most effe...

Appraising Two Techniques for Increasing the Honesty of Students' Answers to Self-Report Assessment Devices.

ERIC Educational Resources Information Center

Popham, W. James

1993-01-01

Techniques for increasing honesty of student self-report measures, the inaccessible coding system and the alphabet-soup response form, were investigated in a study involving over 1,200 high school students. Both techniques were regarded favorably by students. Because both enhance anonymity, it appears that they could be used jointly. (SLD)

A Posteriori Restoration of Block Transform-Compressed Data

NASA Technical Reports Server (NTRS)

Brown, R.; Boden, A. F.

1995-01-01

The Galileo spacecraft will use lossy data compression for the transmission of its science imagery over the low-bandwidth communication system. The technique chosen for image compression is a block transform technique based on the Integer Cosine Transform, a derivative of the JPEG image compression standard. Considered here are two known a posteriori enhancement techniques, which are adapted.

Development of novel series and parallel sensing system based on nanostructured surface enhanced Raman scattering substrate for biomedical application

NASA Astrophysics Data System (ADS)

Chang, Te-Wei

With the advance of nanofabrication, the capability of nanoscale metallic structure fabrication opens a whole new study in nanoplasmonics, which is defined as the investigation of photon-electron interaction in the vicinity of nanoscale metallic structures. The strong oscillation of free electrons at the interface between metal and surrounding dielectric material caused by propagating surface plasmon resonance (SPR) or localized surface plasmon resonance (LSPR) enables a variety of new applications in different areas, especially biological sensing techniques. One of the promising biological sensing applications by surface resonance polariton is surface enhanced Raman spectroscopy (SERS), which significantly reinforces the feeble signal of traditional Raman scattering by at least 104 times. It enables highly sensitive and precise molecule identification with the assistance of a SERS substrate. Until now, the design of new SERS substrate fabrication process is still thriving since no dominant design has emerged yet. The ideal process should be able to achieve both a high sensitivity and low cost device in a simple and reliable way. In this thesis two promising approaches for fabricating nanostructured SERS substrate are proposed: thermal dewetting technique and nanoimprint replica technique. These two techniques are demonstrated to show the capability of fabricating high performance SERS substrate in a reliable and cost efficient fashion. In addition, these two techniques have their own unique characteristics and can be integrated with other sensing techniques to build a serial or parallel sensing system. The breakthrough of a combination system with different sensing techniques overcomes the inherent limitations of SERS detection and leverages it to a whole new level of systematic sensing. The development of a sensing platform based on thermal dewetting technique is covered as the first half of this thesis. The process optimization, selection of substrate material, and improved deposition technique are discussed in detail. Interesting phenomena have been found including the influence of Raman enhancement on substrate material selection and hot-spot rich bimetallic nanostructures by physical vapor deposition on metallic seed array, which are barely discussed in past literature but significantly affect the performance of SERS substrate. The optimized bimetallic backplane assisted resonating nanoantenna (BARNA) SERS substrate is demonstrated with the enhancement factor (EF) of 5.8 x 108 with 4.7 % relative standard deviation. By serial combination with optical focusing from nanojet effect, the nanojet and surface enhanced Raman scattering (NASERS) are proved to provide more than three orders of enhancement and enable us to perform stable, nearly single molecule detection. The second part of this thesis includes the development of a parallel dual functional nano Lycurgus cup array (nanoLCA) plasmonic device fabricated by nanoimprint replica technique. The unique configuration of the periodic nanoscale cup-shaped substrate enables a novel hybrid resonance coupling between SPR from extraordinary (EOT) and LSPR from dense sidewall metal nanoparticles with only single deposition process. The sub-50nm dense sidewall metal nanoparticles lead to high SERS performance in solution based detection, by which most biological and chemical analyses are typically performed. The SERS EF was calculated as 2.8 x 107 in a solution based environment with 10.2 % RSD, which is so far the highest reported SERS enhancement achieved with similar periodic EOT devices. In addition, plasmonic colorimetric sensing can be achieved in the very same device and the sensitivity was calculated as 796 nm/RIU with the FOM of 12.7. It creates a unique complementary sensing platform with both rapid on-site colorimetric screening and follow-up precise Raman analysis for point of care and resource limited environment applications. The implementations of bifunctional sensing on opto-microfluidic and smartphone platforms are proposed and examined here as well.

Comparison of gadobenate dimeglumine-enhanced breast MRI and gadopentetate dimeglumine-enhanced breast MRI with mammography and ultrasound for the detection of breast cancer.

PubMed

Gilbert, Fiona J; van den Bosch, Harrie C M; Petrillo, Antonella; Siegmann, Katja; Heverhagen, Johannes T; Panizza, Pietro; Gehl, Hans-Björn; Pediconi, Federica; Diekmann, Felix; Peng, Wei-Jun; Ma, Lin; Sardanelli, Francesco; Belli, Paolo; Corcione, Stefano; Zechmann, Christian M; Faivre-Pierret, Matthieu; Martincich, Laura

2014-05-01

To compare gadobenate dimeglumine-enhanced magnetic resonance imaging (MRI) with gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound for breast cancer detection across different malignant lesion types and across different densities of breast tissue. In all, 153 women with Breast Imaging Reporting and Data System (BI-RADS) 3–5 findings on mammography and/or ultrasound underwent identical breast MRI exams at 1.5T with gadobenate dimeglumine and gadopentetate dimeglumine. Images were evaluated by three independent blinded radiologists. Mammography, ultrasound, and combined mammography and/or ultrasound findings were available for 108, 109, and 131 women. Imaging findings were matched with histology data by a fourth, independent, blinded radiologist. Malignant lesion detection rates and diagnostic performance were compared. In all, 120, 120, and 140 confirmed malignant lesions were present in patients undergoing MRI+mammography, MRI+ultrasound, and MRI+mammography and/or ultrasound, respectively. Significantly greater cancer detection rates were noted by all three readers for comparisons of gadobenate dimeglumine-enhanced MRI with mammography (Δ15.8–17.5%; P < 0.0001), ultrasound (Δ18.3–20.0%; P < 0.0001), and mammography and/or ultrasound (Δ8.6–10.7%; P ≤ 0.0105) but not for comparisons of gadopentetate dimeglumine-enhanced MRI with conventional techniques (P > 0.05). The false-positive detection rates were lower on gadobenate dimeglumine-enhanced MRI than on conventional imaging (4.0–5.5% vs. 11.1% at mammography; 6.3–8.4% vs. 15.5% at ultrasound). Significantly improved cancer detection on MRI was noted in heterogeneously dense breast (91.2–97.3% on gadobenate dimeglumine-enhanced MRI vs. 77.2–84.9% on gadopentetate dimeglumine-enhanced MRI vs. 71.9-84.9% with conventional techniques) and for invasive cancers (93.2–96.2% for invasive ductal carcinoma [IDC] on gadobenate dimeglumine-enhanced MRI vs. 79.7–88.5% on gadopentetate dimeglumine-enhanced MRI vs. 77.0–84.4% with conventional techniques). Overall diagnostic performance for the detection of cancer was superior on gadobenate dimeglumine-enhanced MRI than on conventional imaging or gadopentetate dimeglumine-enhanced MRI. Gadobenate dimeglumine-enhanced MRI significantly improves cancer detection compared to gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound in a selected group of patients undergoing breast MRI for preoperative staging or because of inconclusive findings at conventional imaging.

EVALUATION OF ANALYTICAL METHODS FOR DETERMINING PESTICIDES IN BABY FOOD

EPA Science Inventory

Three extraction methods and two detection techniques for determining pesticides in baby food were evaluated. The extraction techniques examined were supercritical fluid extraction (SFE), enhanced solvent extraction (ESE), and solid phase extraction (SPE). The detection techni...

Photo-reconnaissance applications of computer processing of images.

NASA Technical Reports Server (NTRS)

Billingsley, F. C.

1971-01-01

An imaging processing technique is developed for enhancement and calibration of imaging experiments. The technique is shown to be useful not only for the original application but also when applied to images from a wide variety of sources.

REMEDIATION OF CONTAMINATED SOILS BY SOLVENT FLUSHING

EPA Science Inventory

Solvent flushing is a potential technique for remediating a waste disposal/spill site contaminated with organic chemicals. This technique involves the injection of a solvent mixture (e.g., water plus alcohols) that enhances contaminant solubility, reduces the retardation factor, ...

Geologic studies of Yellowstone National Park imagery using an electronic image enhancement system

NASA Technical Reports Server (NTRS)

Smedes, H. W.

1970-01-01

The image enhancement system is described, as well as the kinds of enhancement attained. Results were obtained from various kinds of remote sensing imagery (mainly black and white multiband, color, color infrared, thermal infrared, and side-looking K-band radar) of parts of Yellowstone National Park. Possible additional fields of application of these techniques are considered.

Predicted Performance of a Thrust-Enhanced SR-71 Aircraft with an External Payload

NASA Technical Reports Server (NTRS)

Conners, Timothy R.

1997-01-01

NASA Dryden Flight Research Center has completed a preliminary performance analysis of the SR-71 aircraft for use as a launch platform for high-speed research vehicles and for carrying captive experimental packages to high altitude and Mach number conditions. Externally mounted research platforms can significantly increase drag, limiting test time and, in extreme cases, prohibiting penetration through the high-drag, transonic flight regime. To provide supplemental SR-71 acceleration, methods have been developed that could increase the thrust of the J58 turbojet engines. These methods include temperature and speed increases and augmentor nitrous oxide injection. The thrust-enhanced engines would allow the SR-71 aircraft to carry higher drag research platforms than it could without enhancement. This paper presents predicted SR-71 performance with and without enhanced engines. A modified climb-dive technique is shown to reduce fuel consumption when flying through the transonic flight regime with a large external payload. Estimates are included of the maximum platform drag profiles with which the aircraft could still complete a high-speed research mission. In this case, enhancement was found to increase the SR-71 payload drag capability by 25 percent. The thrust enhancement techniques and performance prediction methodology are described.

Writing as Counseling.

ERIC Educational Resources Information Center

Brand, Alice G.

1987-01-01

Promotes writing as a counseling technique to enhance a child's psychological growth. Notes that writing enhances awareness by helping individuals organize their inner selves, contributing to personal integration and self-validation, and providing a cathartic emotional release. Describes current therapeutic writing practices and a therapeutic…

Rapid stabilization of thawing soils For enhanced vehicle mobility: a field demonstration project

DOT National Transportation Integrated Search

1999-02-01

Thawing soil presents a formidable challenge for vehicle operations cross-country and on unsurfaced roads. To mitigate the problem, a variety of stabilization techniques were evaluated for their suitability for rapid employment to enhance military ve...

Color enhancement of landsat agricultural imagery: JPL LACIE image processing support task

NASA Technical Reports Server (NTRS)

Madura, D. P.; Soha, J. M.; Green, W. B.; Wherry, D. B.; Lewis, S. D.

1978-01-01

Color enhancement techniques were applied to LACIE LANDSAT segments to determine if such enhancement can assist analysis in crop identification. The procedure involved increasing the color range by removing correlation between components. First, a principal component transformation was performed, followed by contrast enhancement to equalize component variances, followed by an inverse transformation to restore familiar color relationships. Filtering was applied to lower order components to reduce color speckle in the enhanced products. Use of single acquisition and multiple acquisition statistics to control the enhancement were compared, and the effects of normalization investigated. Evaluation is left to LACIE personnel.

Distributed Generation Planning using Peer Enhanced Multi-objective Teaching-Learning based Optimization in Distribution Networks

NASA Astrophysics Data System (ADS)

Selvam, Kayalvizhi; Vinod Kumar, D. M.; Siripuram, Ramakanth

2017-04-01

In this paper, an optimization technique called peer enhanced teaching learning based optimization (PeTLBO) algorithm is used in multi-objective problem domain. The PeTLBO algorithm is parameter less so it reduced the computational burden. The proposed peer enhanced multi-objective based TLBO (PeMOTLBO) algorithm has been utilized to find a set of non-dominated optimal solutions [distributed generation (DG) location and sizing in distribution network]. The objectives considered are: real power loss and the voltage deviation subjected to voltage limits and maximum penetration level of DG in distribution network. Since the DG considered is capable of injecting real and reactive power to the distribution network the power factor is considered as 0.85 lead. The proposed peer enhanced multi-objective optimization technique provides different trade-off solutions in order to find the best compromise solution a fuzzy set theory approach has been used. The effectiveness of this proposed PeMOTLBO is tested on IEEE 33-bus and Indian 85-bus distribution system. The performance is validated with Pareto fronts and two performance metrics (C-metric and S-metric) by comparing with robust multi-objective technique called non-dominated sorting genetic algorithm-II and also with the basic TLBO.

A 25-Gbps high-sensitivity optical receiver with 10-Gbps photodiode using inductive input coupling for optical interconnects

NASA Astrophysics Data System (ADS)

Oku, Hideki; Narita, Kiyomi; Shiraishi, Takashi; Ide, Satoshi; Tanaka, Kazuhiro

2012-01-01

A 25-Gbps high-sensitivity optical receiver with a 10-Gbps photodiode (PD) using inductive input coupling has been demonstrated for optical interconnects. We introduced the inductive input coupling technique to achieve the 25-Gbps optical receiver using a 10-Gbps PD. We implemented an input inductor (Lin) between the PD and trans-impedance amplifier (TIA), and optimized inductance to enhance the bandwidth and reduce the input referred noise current through simulation with the RF PD-model. Near the resonance frequency of the tank circuit formed by PD capacitance, Lin, and TIA input capacitance, the PD photo-current through Lin into the TIA is enhanced. This resonance has the effects of enhancing the bandwidth at TIA input and reducing the input equivalent value of the noise current from TIA. We fabricated the 25-Gbps optical receiver with the 10-Gbps PD using an inductive input coupling technique. Due to the application of an inductor, the receiver bandwidth is enhanced from 10 GHz to 14.2 GHz. Thanks to this wide-band and low-noise performance, we were able to improve the sensitivity at an error rate of 1E-12 from non-error-free to -6.5 dBm. These results indicate that our technique is promising for cost-effective optical interconnects.

Enhancement of Raman scattering signal of a few molecules using photonic nanojet mediated SERS technique

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

Das, G. M.; Parit, M. K.; Laha, R.

2016-05-06

Now a days, single molecule surface enhanced Raman spectroscopy (SMSERS) has become a fascinating tool for studying the structural properties, static and dynamic events of single molecules (instead of ensemble average), with the help of efficient plasmonic nanostructures. This is extremely useful in the field of proteomics because the structural properties of protein molecules are heterogeneous. Even though, SMSERS provides wealthy information about single molecules, it demands high quality surface enhanced Raman scattering (SERS) substrates. So far, a very few researchers succeeded in demonstrating the single molecule Raman scattering using conventional SERS technique. However, the experimental S/N of the Ramanmore » signal has been found to be very poor. Recently, with the help of photonic nanojet of an optical microsphere, we were able to enhance the SERS signal of a few molecules adsorbed on the SERS substrates (gold symmetric and asymmetric nanodimers and trimers dispersed on a glass slide). Herein, we report a few details about photonic nanojet mediated SERS technique, a few experimental results and a detailed theoretical study on symmetric and asymmetric nanosphere dimers to understand the dependence of localised surface plasmon resonance (LSPR) wavelength of a nanodimer on the nanogap size and polarization of the excitation light.« less

Personal Photo Enhancement Using Internet Photo Collections.

PubMed

Zhang, Chenxi; Gao, Jizhou; Wang, Oliver; Georgel, Pierre; Yang, Ruigang; Davis, James; Frahm, Jan-Michael; Pollefeys, Marc

2013-04-26

Given the growth of Internet photo collections we now have a visual index of all major cities and tourist sites in the world. However, it is still a difficult task to capture that perfect shot with your own camera when visiting these places, especially when your camera itself has limitations, such as a limited field of view. In this paper, we propose a framework to overcome the imperfections of personal photos of tourist sites using the rich information provided by large scale Internet photo collections. Our method deploys state-of-the-art techniques for constructing initial 3D models from photo collections. The same techniques are then used to register personal photos to these models, allowing us to augment personal 2D images with 3D information. This strong available scene prior allows us to address a number of traditionally challenging image enhancement techniques, and achieve high quality results using simple and robust algorithms. Specifically, we demonstrate automatic foreground segmentation, mono-to-stereo conversion, the field of view expansion, photometric enhancement, and additionally automatic annotation with geo-location and tags. Our method clearly demonstrates some possible benefits of employing the rich information contained in on-line photo databases to efficiently enhance and augment one’s own personal photos.

Enhanced microwave characterisation technique for cryogenic temperatures

NASA Astrophysics Data System (ADS)

Smuk, J. W.; Stubbs, M. G.; Wight, J. S.

1990-12-01

A real-time technique to de-embed broadband S-parameter measurements of MIC/MMIC devices at temperatures down to 13 K is presented. Exceptional accuracy is obtained by using a split-block test fixture and the TRL calibration technique at cryogenic temperatures for the first time. The repeatability of the technique and the measurement of a transmission line at 297 K and 77 K are demonstrated from 0.1 GHz to 20 GHz.

Psychological skills training as a way to enhance an athlete's performance in high-intensity sports.

PubMed

Birrer, D; Morgan, G

2010-10-01

The importance of psychological skills training (PST) in the development of athletic performance is widely recognized. This paper is a comprehensive review of PST in elite sports, with a special focus on high-intensity sports (HIS). The reviewed literature showed a lack of convincing evidence and theoretical underpinning concerning traditional psychological skills to enhance performance in HIS. Therefore, a model with three conceptual levels (psychological demands, skills and techniques) is presented. The model facilitates the identification of the psychological demands of a specific sport, which in turn enables distinguishing which psychological skills are required. This allows an expert to choose psychological techniques to improve the athlete's psychological skill. Considerations based on our model and the limited HIS-related literature available revealed self-skills, personal development and life skills, arousal-regulation skills, volitional skills, motivational skills and recovery skills as the most important skills to address in order to enhance performance. Development of harmonious passion, in-practice integration of volitional strategies, use of associative attentional techniques, pain management techniques, use of the mindfulness-acceptance approach and the facilitative interpretation of cognitive and somatic sensations are regarded as suitable to meet the psychological demands of HIS. They are recommended for systematic application by athletes and coaches. © 2010 John Wiley & Sons A/S.

Contrast enhanced ultrasonography in assessing the treatment response to transarterial chemoembolization in patients with hepatocellular carcinoma.

PubMed

Sparchez, Zeno; Mocan, Tudor; Radu, Pompilia; Anton, Ofelia; Bolog, Nicolae

2016-03-01

The last decades have known continuous development of therapeutic strategies in hepatocellular carcinoma (HCC). Unfortunately the disease it still not diagnosed until it is already at an intermediate or even an advanced disease. In these circumstances transarterial chemoembolization (TACE) is considered an effective treatment for HCC. The most important independent prognostic factor of both disease free survival and overall survival is the presence of complete necrosis. Therefore, treatment outcomes are dictated by the proper use of radiological imaging. Current guidelines recommend contrast enhanced computer tomography (CECT) as the standard imaging technique for evaluating the therapeutic response in patients with HCC after TACE. One of the most important disadvantage of CECT is the overestimation of tumor response. As an attempt to overcome this limitation contrast enhanced ultrasound (CEUS) has gained particular attention as an imaging modality in HCC patients after TACE. Of all available imaging modalities, CEUS performs better in the early and very early assessment of TACE especially after lipiodol TACE. As any other imaging techniques CEUS has disadvantages especially in hypovascular tumors or in cases of tumor multiplicity. Not far from now the current limitations of CEUS will be overcome by the new CEUS techniques that are already tested in clinical practice such as dynamic CEUS with quantification, three-dimensional CEUS or fusion techniques.

Linear Covariance Analysis For Proximity Operations Around Asteroid 2008 EV5

NASA Technical Reports Server (NTRS)

Wright, Cinnamon A.; Bhatt, Sagar; Woffinden, David; Strube, Matthew; D'Souza, Chris

2015-01-01

The NASA initiative to collect an asteroid, the Asteroid Robotic Redirect Mission (ARRM), is currently investigating the option of retrieving a boulder from an asteroid, demonstrating planetary defense with an enhanced gravity tractor technique, and returning it to a lunar orbit. Techniques for accomplishing this are being investigated by the Satellite Servicing Capabilities Office (SSCO) at NASA GSFC in collaboration with JPL, NASA JSC, LaRC, and Draper Laboratory, Inc. Two critical phases of the mission are the descent to the boulder and the Enhanced Gravity Tractor demonstration. A linear covariance analysis is done for these phases to assess the feasibility of these concepts with the proposed design of the sensor and actuator suite of the Asteroid Redirect Vehicle (ARV). The sensor suite for this analysis includes a wide field of view camera, LiDAR, and an IMU. The proposed asteroid of interest is currently the C-type asteroid 2008 EV5, a carbonaceous chondrite that is of high interest to the scientific community. This paper presents an overview of the linear covariance analysis techniques and simulation tool, provides sensor and actuator models, and addresses the feasibility of descending to the surface of the asteroid within allocated requirements as well as the possibility of maintaining a halo orbit to demonstrate the Enhanced Gravity Tractor technique.

A comparison of line enhancement techniques: applications to guide-wire detection and respiratory motion tracking

NASA Astrophysics Data System (ADS)

Bismuth, Vincent; Vancamberg, Laurence; Gorges, Sébastien

2009-02-01

During interventional radiology procedures, guide-wires are usually inserted into the patients vascular tree for diagnosis or healing purpose. These procedures are monitored with an Xray interventional system providing images of the interventional devices navigating through the patient's body. The automatic detection of such tools by image processing means has gained maturity over the past years and enables applications ranging from image enhancement to multimodal image fusion. Sophisticated detection methods are emerging, which rely on a variety of device enhancement techniques. In this article we reviewed and classified these techniques into three families. We chose a state of the art approach in each of them and built a rigorous framework to compare their detection capability and their computational complexity. Through simulations and the intensive use of ROC curves we demonstrated that the Hessian based methods are the most robust to strong curvature of the devices and that the family of rotated filters technique is the most suited for detecting low CNR and low curvature devices. The steerable filter approach demonstrated less interesting detection capabilities and appears to be the most expensive one to compute. Finally we demonstrated the interest of automatic guide-wire detection on a clinical topic: the compensation of respiratory motion in multimodal image fusion.

Transformer-Feedback Interstage Bandwidth Enhancement for MMIC Multistage Amplifiers

NASA Astrophysics Data System (ADS)

Nikandish, Gholamreza; Medi, Ali

2015-02-01

The transformer-feedback (TRFB) interstage bandwidth enhancement technique for broadband multistage amplifiers is presented. Theory of the TRFB bandwidth enhancement and the design conditions for maximum bandwidth, maximally flat gain, and maximally flat group delay are provided. It is shown that the TRFB bandwidth enhancement can provide higher bandwidth compared to the conventional techniques based on reactive impedance matching networks. A three-stage low-noise amplifier (LNA) monolithic microwave integrated circuit with the TRFB between its consecutive stages is designed and implemented in a 0.1- μm GaAs pHEMT process. The TRFB is realized by coupling between the drain bias lines of transistors. The reuse of bias lines leads to bandwidth enhancement without increasing the chip area and power consumption. The LNA features average gain of 23 dB and 3-dB bandwidth of 11-39 GHz. It provides a noise figure of 2.1-3.0 dB and an output 1-dB compression point of 8.6 dBm, while consuming 40 mA of current from a 2-V supply.

Optimization of subcutaneous vein contrast enhancement

NASA Astrophysics Data System (ADS)

Zeman, Herbert D.; Lovhoiden, Gunnar; Deshmukh, Harshal

2000-05-01

A technique for enhancing the contrast of subcutaneous veins has been demonstrated. This techniques uses a near IR light source and one or more IR sensitive CCD TV cameras to produce a contrast enhanced image of the subcutaneous veins. This video image of the veins is projected back onto the patient's skin using a n LCD video projector. The use of an IR transmitting filter in front of the video cameras prevents any positive feedback from the visible light from the video projector from causing instabilities in the projected image. The demonstration contrast enhancing illuminator has been tested on adults and children, both Caucasian and African-American, and it enhances veins quite well in all cases. The most difficult cases are those where significant deposits of subcutaneous fat are present which make the veins invisible under normal room illumination. Recent attempts to see through fat using different IR wavelength bands and both linearly and circularly polarized light were unsuccessful. The key to seeing through fat turns out to be a very diffuse source of RI light. Results on adult and pediatric subjects are shown with this new IR light source.

Enhanced Performance of Thin Film Composite Forward Osmosis Membrane by Chemical Post-Treatment

NASA Astrophysics Data System (ADS)

Liu, Zheng; Chen, Jiangrong; Cao, Zhen; Wang, Jian; Guo, Chungang

2018-01-01

Forward osmosis is an attractive technique in water purification and desalination fields. Enhancement of the forward osmosis membrane performance is essential to the application of this technique. In this study, an optimized chemical post-treatment approach which was used to improve RO membrane performance was employed for enhancing water flux of thin film composite forward osmosis membrane. Home-made polysulfide-based forward osmosis membrane was prepared and nitric acid, sulfuric acid, ethanol, 2-propanol were employed as post-treatment solutions. After a short-term treatment, all the membrane samples manifested water flux enhancement compared with their untreated counterparts. Over 50% increase of water flux had been obtained by ethanol solution treatment. The swelling, changes of hydrophobicity and solvency in both active layer and substrate were verified as the major causes for the enhancement of the water flux. It is noted that the treatment time and solution concentration should be controlled to get both appropriate water flux and reverse salt flux. The results obtained in this study will be useful for further FO membrane development and application.

DeMAID/GA an Enhanced Design Manager's Aid for Intelligent Decomposition

NASA Technical Reports Server (NTRS)

Rogers, J. L.

1996-01-01

Many companies are looking for new tools and techniques to aid a design manager in making decisions that can reduce the time and cost of a design cycle. One tool is the Design Manager's Aid for Intelligent Decomposition (DeMAID). Since the initial public release of DeMAID in 1989, much research has been done in the areas of decomposition, concurrent engineering, parallel processing, and process management; many new tools and techniques have emerged. Based on these recent research and development efforts, numerous enhancements have been added to DeMAID to further aid the design manager in saving both cost and time in a design cycle. The key enhancement, a genetic algorithm (GA), will be available in the next public release called DeMAID/GA. The GA sequences the design processes to minimize the cost and time in converging a solution. The major enhancements in the upgrade of DeMAID to DeMAID/GA are discussed in this paper. A sample conceptual design project is used to show how these enhancements can be applied to improve the design cycle.

Coatings for minimally processed fruits and vegetables

USDA-ARS?s Scientific Manuscript database

Fresh-cut fruit and vegetables are gaining increasing popularity and market share. Techniques to enhance stability of fresh cut produce are reviewed. Among these techniques, edibles coatings can provide protection against dehydration, microbial decay and decrease events related to physiological sene...

Photoacoustic Techniques for Trace Gas Sensing Based on Semiconductor Laser Sources

PubMed Central

Elia, Angela; Lugarà, Pietro Mario; Di Franco, Cinzia; Spagnolo, Vincenzo

2009-01-01

The paper provides an overview on the use of photoacoustic sensors based on semiconductor laser sources for the detection of trace gases. We review the results obtained using standard, differential and quartz enhanced photoacoustic techniques. PMID:22303143

The Techniques of Teletraining--New Enhancements.

ERIC Educational Resources Information Center

Kundu, Mahima Ranjan

1993-01-01

Discusses potential benefits of audio and video teletraining as an effective tool for distance education in the Department of Defense. Teletraining needs assessment is addressed; instructional design techniques are discussed, including the use of lesson modules; and trainee involvement is considered. (LRW)

Evaluation of Marrow Perfusion in the Femoral Head by Dynamic Magnetic Resonance Imaging

PubMed Central

Tsukamoto, Hiroshi; Kang, Young S.; Jones, Lynne C.; Cova, Maria; Herold, Christian J.; McVeigh, Elliot; Hungerford, David S.; Zerhouni, Elias A.

2007-01-01

Rationale and Objectives There is a continuing need for a greater sensitivity of magnetic resonance imaging (MRI) in the diagnosis of avascular necrosis (AVN). Previously, it was demonstrated that a dynamic MRI method, with gadolinium-DTPA (Gd-DTPA) enhancement, can detect acute changes not seen on spin-echo images after arterial occlusion in a dog model. Because venous congestion appears to be a more directly relevant hemodynamic abnormality in a majority of clinical AVN cases, the authors extended the dynamic MRI technique to study changes in venous occlusion. Methods Dynamic MRI of the proximal femur was performed in five adult dogs before and after unilateral ligation of common iliac and lateral circumflex veins. Sixteen sequential gradient-recalled pulse sequence (GRASS) images (time resolution = 45 mseconds, echo time = 9 mseconds, flip angle = 65°) were obtained immediately after a bolus intravenous injection of 0.2 mmol/kg of Gd-DTPA. Simultaneous measurements of regional blood flow were made using the radioactive microsphere method. Results After venous ligation, there was a 25% to 45% decrease in the degree of enhancement compared with preligation values on the ligated side. The decrease in cumulative enhancement (integrated over the entire time course) was statistically significant. The occlusion technique was verified by confirming a statistically significant decrease in blood flow determined by the microsphere method. Conclusions Dynamic Gd-DTPA-enhanced fast MRI technique can detect acute changes in bone marrow perfusion due to venous occlusion. This technique may have applications in the early detection of nontraumatic AVN. PMID:1601616

Enhancing the bioavailability of mebendazole by integrating the principles solid dispersion and nanocrystal techniques, for safe and effective management of human echinococcosis.

PubMed

Chaudhary, Sushant; Garg, Tarun; Rath, Goutam; Murthy, Rs Rayasa; Goyal, Amit K

2016-05-01

The method based on integrating the principles of solid dispersion and nanocrystal techniques was developed to prepare polymer crystals (PCs) of mebendazole (MBZ) and polyethylene glycol (PEG). Powder X-Ray diffraction (PXRD) of the PC crystals shows the required integrated crystalline and amorphous regions. The in vitro solubility studies showed a 32-fold increase in the solubility of the drug. Tests of dissolution of the PCs showed that the crystals have an enhanced dissolution rate in comparison to those in the MF. The results of the pharmacokinetic study showed a 2.12-fold increase in the bioavailability of the drug. Thus, the present study has proved the potential in enhancing solubility, dissolution, and bioavailability of the drug.

Arsenic detection in water: YPO{sub 4}:Eu{sup 3+} nanoparticles

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

Ghosh, Debasish; Luwang, Meitram Niraj, E-mail: mn.luwang@ncl.res.in; Academy of Scientific and Innovative Research

This work reports on the novel technique of detection of arsenic in aqueous solution utilising the luminescence properties of lanthanide doped nanomaterials. Eu{sup 3+} (5%) doped YPO{sub 4}nanorodswere utilised for the said experiment. Co-precipitation method was used for the synthesis of the materials and characterised them with different instrumental techniques like X-ray diffraction (XRD), Infra-red (IR), UV-absorption, scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence studies. This nanoparticle can adsorb both arsenic and arsenious acids. We studied the effect of arsenic adsorption on the luminescence behaviour of the nanoparticles. Arsenic acid enhanced the luminescencemore » intensity whereas arsenious acid quenched the luminescence. This luminescence enhancement or quenching is related with arsenic concentration. This relation of luminescence property with concentration of arsenic can be used to detect arsenic in industrial waste. - Graphical abstract: Novel technique of detection of Arsenic ion in aqueous solution utilising the luminescence properties of lanthanide doped nanomaterials. Potential application for detection of arsenic in drinking and industrial waste water. - Highlights: • Novel technique of detection of Arsenic in aqueous solution by YPO{sub 4}:Eu{sup 3+} nanomaterials. • The effect of arsenic adsorption on the luminescence behaviour of the nanoparticles was studied. • Arsenic acid enhance whereas arsenious acid quenches the luminescence intensity. • This technique can be used to detect arsenic in industrial waste.« less

Biological sensing with surface-enhanced Raman spectroscopy (SERS) using a facile and rapid silver colloid-based synthesis technique

NASA Astrophysics Data System (ADS)

Smyth, C.; Mehigan, S.; Rakovich, Y. P.; Bell, S. E. J.; McCabe, E. M.

2011-03-01

Optical techniques towards the realisation of sensitive and selective biosensing platforms have received a considerable amount of attention in recent times. Techniques based on interferometry, surface plasmon resonance, field-effect transistors and waveguides have all proved popular, and in particular, spectroscopy offers a large range of options. Raman spectroscopy has always been viewed as an information rich technique in which the vibrational frequencies reveal a lot about the structure of a compound. The issue with Raman spectroscopy has traditionally been that its rather low cross section leads to poor limits-of-detection. In response to this problem, Surface-enhanced Raman Scattering (SERS), which increases sensitivity by bringing the sample in contact with many types of enhanceing substrates, has been developed. Here we discuss a facile and rapid technique for the detection of pterins using colloidal silver suspensions. Pteridine compounds are a family of biochemicals, heterocyclic in structure, and employed in nature as components of colour pigmentation and also as facilitators for many metabolic pathways, particularly those relating to the amino acid hydroxylases. In this work, xanthopterin, isoxanthopterin and 7,8- dihydrobiopterin have been examined whilst absorbed to SERS-active silver colloids. SERS, while far more sensitive than regular Raman spectroscopy, has its own issues relating to the reproducibility of substrates. In order to obtain quantitative data for the pteridine compounds mentioned above, exploratory studies of methods for introducing an internal standard for normalisation of the signals have been carried out.e

Enhanced Lamb dip for absolute laser frequency stabilization

NASA Technical Reports Server (NTRS)

Siegman, A. E.; Byer, R. L.; Wang, S. C.

1972-01-01

Enhanced Lamb dip width is 5 MHz and total depth is 10 percent of peak power. Present configuration is useful as frequency standard in near infrared. Technique extends to other lasers, for which low pressure narrow linewidth gain tubes can be constructed.

Feature-extracted joint transform correlation.

PubMed

Alam, M S

1995-12-10

A new technique for real-time optical character recognition that uses a joint transform correlator is proposed. This technique employs feature-extracted patterns for the reference image to detect a wide range of characters in one step. The proposed technique significantly enhances the processing speed when compared with the presently available joint transform correlator architectures and shows feasibility for multichannel joint transform correlation.

Turbulent flow separation control through passive techniques

NASA Technical Reports Server (NTRS)

Lin, J. C.; Howard, F. G.; Selby, G. V.

1989-01-01

Several passive separation control techniques for controlling moderate two-dimensional turbulent flow separation over a backward-facing ramp are studied. Small transverse and swept grooves, passive porous surfaces, large longitudinal grooves, and vortex generators were among the techniques used. It was found that, unlike the transverse and longitudinal grooves of an equivalent size, the 45-deg swept-groove configurations tested tended to enhance separation.

Environmental Electrokinetics for a sustainable subsurface.

PubMed

Lima, A T; Hofmann, A; Reynolds, D; Ptacek, C J; Van Cappellen, P; Ottosen, L M; Pamukcu, S; Alshawabekh, A; O'Carroll, D M; Riis, C; Cox, E; Gent, D B; Landis, R; Wang, J; Chowdhury, A I A; Secord, E L; Sanchez-Hachair, A

2017-08-01

Soil and groundwater are key components in the sustainable management of the subsurface environment. Source contamination is one of its main threats and is commonly addressed using established remediation techniques such as in-situ chemical oxidation (ISCO), in-situ chemical reduction (ISCR; most notably using zero-valent iron [ZVI]), enhanced in-situ bioremediation (EISB), phytoremediation, soil-washing, pump-and-treat, soil vapour extraction (SVE), thermal treatment, and excavation and disposal. Decades of field applications have shown that these techniques can successfully treat or control contaminants in higher permeability subsurface materials such as sands, but achieve only limited success at sites where low permeability soils, such as silts and clays, prevail. Electrokinetics (EK), a soil remediation technique mostly recognized in in-situ treatment of low permeability soils, has, for the last decade, been combined with more conventional techniques and can significantly enhance the performance of several of these remediation technologies, including ISCO, ISCR, EISB and phytoremediation. Herein, we discuss the use of emerging EK techniques in tandem with conventional remediation techniques, to achieve improved remediation performance. Furthermore, we highlight new EK applications that may come to play a role in the sustainable treatment of the contaminated subsurface. Copyright © 2017 Elsevier Ltd. All rights reserved.

Visualization and characterization of the acoustic radiation force assisted displacement of particles using an OCT technique (Conference Presentation)

NASA Astrophysics Data System (ADS)

Razani, Marjan; Zam, Azhar; Arezza, Nico J. J.; Wang, Yan J.; Kolios, Michael C.

2016-03-01

In this study, we present a technique to image the enhanced particle displacement generated using an acoustic radiation force (ARF) excitation source. A swept-source OCT (SS-OCT) system with a center wavelength of 1310nm, a bandwidth of ~100nm, and an A-scan rate of 100 kHz (MEMS-VCSEL OCT Thorlabs) was used to detect gold nanoparticle (70nm in diameter) displacement .ARF was applied after the nanoparticles passed through a porous membrane and diffused into a collagen (6% collagen) matrix. B-mode, M-B mode, 3D and Speckle Variance (SV) images were acquired before and after the ARF beam was on. Differential OCT speckle variance images with and without the ARF were used to measure the particle displacement. The images were used to detect the microscopic enhancement of nanoparticle displacement generated by the ARF. Using this OCT imaging technique, the extravasation of particles though a porous membrane and characterization of the enhanced particle displacement in a collagen gel after using an ARF excitation was achieved.

Generalized image contrast enhancement technique based on the Heinemann contrast discrimination model

NASA Astrophysics Data System (ADS)

Liu, Hong; Nodine, Calvin F.

1996-07-01

This paper presents a generalized image contrast enhancement technique, which equalizes the perceived brightness distribution based on the Heinemann contrast discrimination model. It is based on the mathematically proven existence of a unique solution to a nonlinear equation, and is formulated with easily tunable parameters. The model uses a two-step log-log representation of luminance contrast between targets and surround in a luminous background setting. The algorithm consists of two nonlinear gray scale mapping functions that have seven parameters, two of which are adjustable Heinemann constants. Another parameter is the background gray level. The remaining four parameters are nonlinear functions of the gray-level distribution of the given image, and can be uniquely determined once the previous three are set. Tests have been carried out to demonstrate the effectiveness of the algorithm for increasing the overall contrast of radiology images. The traditional histogram equalization can be reinterpreted as an image enhancement technique based on the knowledge of human contrast perception. In fact, it is a special case of the proposed algorithm.

Minimally Invasive Techniques to Accelerate the Orthodontic Tooth Movement: A Systematic Review of Animal Studies

PubMed Central

Qamruddin, Irfan; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli; Husein, Adam

2015-01-01

Objective. To evaluate various noninvasive and minimally invasive procedures for the enhancement of orthodontic tooth movement in animals. Materials and Methods. Literature was searched using NCBI (PubMed, PubMed Central, and PubMed Health), MedPilot (Medline, Catalogue ZB MED, Catalogue Medicine Health, and Excerpta Medica Database (EMBASE)), and Google Scholar from January 2009 till 31 December 2014. We included original articles related to noninvasive and minimally invasive procedures to enhance orthodontic tooth movement in animals. Extraction of data and quality assessments were carried out by two observers independently. Results. The total number of hits was 9195 out of which just 11 fulfilled the inclusion criteria. Nine articles were good and 5 articles were moderate in quality. Low level laser therapy (LLLT) was among the most common noninvasive techniques whereas flapless corticision using various instruments was among the commonest minimally invasive procedures to enhance velocity of tooth movement. Conclusions. LLLT, low intensity pulsed ultrasound (LIPUS), mechanical vibration, and flapless corticision are emerging noninvasive and minimally invasive techniques which need further researches to establish protocols to use them clinically with conviction. PMID:26881201

Nonlinear oscillation and interfacial stability of an encapsulated microbubble under dual-frequency ultrasound

NASA Astrophysics Data System (ADS)

Calvisi, Michael; Liu, Yunqiao; Wang, Qianxi

2016-11-01

Encapsulated microbubbles (EMBs) are widely used in medical ultrasound imaging as contrast-enhanced agents. However, the potential damaging effects of violent, collapsing EMBs to cells and tissues in clinical practice have remained a concern. Dual-frequency ultrasound is a promising technique for improving the efficacy and safety of sonography. The EMB system modeled consists of the external liquid, membrane, and internal gases. The microbubble dynamics are simulated using a simple nonlinear interactive theory, considering the compressibility of the internal gas, viscosity of the liquid flow, and elasticity of the membrane. The radial oscillation and interfacial stability of an EMB under single and dual-frequency excitations are compared. The simulation results show that the dual-frequency technique produces larger backscatter pressure at higher harmonics of the primary driving frequency. This enriched acoustic spectrum can enhance blood-tissue contrast and improve sonographic image quality. The results further show that the acoustic pressure threshold associated with the onset of shape instability is greater for dual-frequency driving. This suggests that the dual-frequency technique stabilizes the EMB, thereby improving the efficacy and safety of contrast-enhanced agents.

Mid-IR enhanced laser ablation molecular isotopic spectrometry

NASA Astrophysics Data System (ADS)

Brown, Staci; Ford, Alan; Akpovo, Codjo A.; Johnson, Lewis

2016-08-01

A double-pulsed laser-induced breakdown spectroscopy (DP-LIBS) technique utilizing wavelengths in the mid-infrared (MIR) for the second pulse, referred to as double-pulse LAMIS (DP-LAMIS), was examined for its effect on detection limits compared to single-pulse laser ablation molecular isotopic spectrometry (LAMIS). A MIR carbon dioxide (CO2) laser pulse at 10.6 μm was employed to enhance spectral emissions from nanosecond-laser-induced plasma via mid-IR reheating and in turn, improve the determination of the relative abundance of isotopes in a sample. This technique was demonstrated on a collection of 10BO and 11BO molecular spectra created from enriched boric acid (H3BO3) isotopologues in varying concentrations. Effects on the overall ability of both LAMIS and DP-LAMIS to detect the relative abundance of boron isotopes in a starting sample were considered. Least-squares fitting to theoretical models was used to deduce plasma parameters and understand reproducibility of results. Furthermore, some optimization for conditions of the enhanced emission was achieved, along with a comparison of the overall emission intensity, plasma density, and plasma temperature generated by the two techniques.

A survey of various enhancement techniques for square rings antennas

NASA Astrophysics Data System (ADS)

Mumin, Abdul Rashid O.; Alias, Rozlan; Abdullah, Jiwa; Abdulhasan, Raed Abdulkareem; Ali, Jawad; Dahlan, Samsul Haimi; Awaleh, Abdisamad A.

2017-09-01

The square ring shape becomes a famous reconfiguration on antenna design. The researchers have been developed the square ring by different configurations. It has high efficiency and simple calculation method. The performance enhancement for an antenna is the main reason to use this setting. Furthermore, the multi-objectives for the antenna also are considered. In this paper, different studies of square ring shape are discussed. This shape is developed in five different techniques, which are the gain enhancement, dual band antenna, reconfigurable antenna, CSRR, and circularly polarization. Moreover, the validation between these configurations also demonstrates for square ring shapes. In particular, the square ring slot improved the gain by 4.3 dB, provide dual band resonance at 1.4 and 2.6 GHz while circular polarization at 1.54 GHz, and multi-mode antenna. However, square ring strip achieved an excellent band rejection on UWB antenna at 5.5 GHz. The square ring slot length is the most influential factor on the antenna performance, which refers to the free space wavelength. Finally, comparisons between these techniques are presented.

Environmental Development Plan (EDP). Enhanced gas recovery, FY 1977

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

Not Available

1978-03-01

This Enhanced Gcs Recovery EDP addresses the environmental impacts of enhanced gas recovery processes in shale and sandstone, methane drainage from coalbeds, and methane recovery from geopressured aquifers. The EDP addresses planning in two basic areas: environmental research and environmental assessment. Environmental research can be categorized as follows: characterization of pollutants from EGR processes; selective application of monitoring and measuring techniques; evaluation of control/mitigation techniques; and evaluation of the synergistic impacts of the development of EGR techniques. Environmental assessment activities scheduled by EDP include: assessment of ecological impacts; assessment of socioeconomic effects; EIA/EIS preparation; evaluation of control technology needs; andmore » analysis of applicable and proposed emission, effluent, and health and safety standards. The EGR EDP includes an EGR technology overview (Section 2), a discussion of EGR environmental issues and requirements (Section 3), an environmental action plan (Section 4), an environmental management strategy for the EGR program (Section 5), and supporting appendices which present information on Federal legislation applicable to EGR technology, a summary of ongoing and completed research, and future research and assessment projects.« less

The post-humanist embryo: genetic manipulation, assisted reproductive technologies and the Principle of Procreative Beneficence.

PubMed

Güell Pelayo, Francisco

2014-01-01

Drawing from Julian Savulescu's argument for the obligation to use technological interventions for the enhancement human life, the Principle of Procreative Beneficence (PPB) states that parents have a moral obligation to use available reproductive technologies, including techniques of genetic manipulation, to create children who have the best chance of enjoying the best possible life. The aim of this study is to analyse the extent to which the possibility of using genetic manipulation to promote specific personality traits and thereby enhance human life is actually supported by current scientific knowledge and to determine whether the techniques employed in embryo selection comply with the PPB. In light of this analysis, the importance of involving the scientific community in the enhancement debate will be made clear. Moreover, when current knowledge of genetic and epigenetic processes and evidence of the risks of assisted reproductive technologies are taken into account, we find sufficient reason - even when guided by the PPB - to abstain from the use of current techniques of genetic manipulation and embryonic selection.

Facilitating the exploitation of ERTS imagery using snow enhancement techniques

NASA Technical Reports Server (NTRS)

Wobber, F. J. (Principal Investigator); Martin, K. R.; Sheffield, C.; Russell, O.; Amato, R. V.

1972-01-01

The author has identified the following significant results. Analysis of all available (Gemini, Apollo, Nimbus, NASA aircraft) small scale snow covered imagery has been conducted to develop and refine snow enhancement techniques. A detailed photographic interpretation of ERTS-simulation imagery covering the Feather River/Lake Tahoe area was completed and the 580-680nm. band was determined to be the optimum band for fracture detection. ERTS-1 MSS bands 5 and 7 are best suited for detailed fracture mapping. The two bands should provide more complete fracture detail when utilized in combination. Analysis of early ERTS-1 data along with U-2 ERTS simulation imagery indicates that snow enhancement is a viable technique for geological fracture mapping. A wealth of fracture detail on snow-free terrain was noted during preliminary analysis of ERTS-1 images 1077-15005-6 and 7, 1077-15011-5 and 7, and 1079-15124-5 and 7. A direct comparison of data yield on snow-free versus snow-covered terrain will be conducted within these areas following receipt of snow-covered ERTS-1 imagery.

Effect of passive concentration as instructional set for training enhancement of EEG alpha.

PubMed

Knox, S S

1980-12-01

The technique of passive concentration, employed by autogenic training and Transcendental Meditation for achieving relaxation, was tested here as a technique for enhancing EEG alpha. Of 30 subjects displaying between 15% and 74% alpha in their resting EEGs recruited, 10 had to be eliminated. The remaining 20 constituted two groups. One was instructed only to attempt to maintain a tone indicating alpha but given no information about technique (control group). The other was given additional instructions in passive concentration (experimental group). Both were given four 5-min. trials a day for 4 consecutive days. Heart rate and skin conductance were measured to monitor autonomic arousal. The group receiving instructions in passive concentration had significantly less alpha than the control group, which did not increase amount of alpha above baseline. The reduction of alpha in the experimental group was interpreted as resulting from beginning long training periods (20 min. per day), a practice advocated by Transcendental Meditation but discouraged by autogenic training. It was concluded that the relevance of passive concentration for alpha enhancement is doubtful.

Enhanced dissolution, stability and physicochemical characterization of ATRA/2-hydroxypropyl-β-cyclodextrin inclusion complex pellets prepared by fluid-bed coating technique.

PubMed

Chen, Zhongjian; Lu, Yi; Qi, Jianping; Wu, Wei

2013-02-01

The aim of this work was to prepare stable all-trans-retinoic acid (ATRA)/2-hydroxypropyl-β-cyclodextrin (HPCD) inclusion complex pellets with industrial feasible technology, the fluid-bed coating technique, using PVP K30 simultaneously as binder and reprecipitation retarder. The coating process was fluent with high coating efficiency. In vitro dissolution of the inclusion complex pellets in 5% w/v Cremopher EL solution was dramatically enhanced with no reprecipitation observed, and significantly improved stability against humidity (92.5% and 75% RH) and illumination (4500 lx ± 500 lx) was achieved by HPCD inclusion. Differential scanning calorimetry and powder X-ray diffractometry confirmed the absence of crystallinity of ATRA. Fourier transform-infrared spectrometry revealed interaction between ATRA and HPCD adding evidence on inclusion of ATRA moieties into HPCD cavities. Solid-state (13)C NMR spectrometry indicated possible inclusion of ATRA through the polyene chain, which was the main reason for the enhanced photostability. It is concluded that the fluid-bed coating technique has the potential use in the industrial preparation of ATRA/HPCD inclusion complex pellets.

Comparison of Image Processing Techniques for Nonviable Tissue Quantification in Late Gadolinium Enhancement Cardiac Magnetic Resonance Images.

PubMed

Carminati, M Chiara; Boniotti, Cinzia; Fusini, Laura; Andreini, Daniele; Pontone, Gianluca; Pepi, Mauro; Caiani, Enrico G

2016-05-01

The aim of this study was to compare the performance of quantitative methods, either semiautomated or automated, for left ventricular (LV) nonviable tissue analysis from cardiac magnetic resonance late gadolinium enhancement (CMR-LGE) images. The investigated segmentation techniques were: (i) n-standard deviations thresholding; (ii) full width at half maximum thresholding; (iii) Gaussian mixture model classification; and (iv) fuzzy c-means clustering. These algorithms were applied either in each short axis slice (single-slice approach) or globally considering the entire short-axis stack covering the LV (global approach). CMR-LGE images from 20 patients with ischemic cardiomyopathy were retrospectively selected, and results from each technique were assessed against manual tracing. All methods provided comparable performance in terms of accuracy in scar detection, computation of local transmurality, and high correlation in scar mass compared with the manual technique. In general, no significant difference between single-slice and global approach was noted. The reproducibility of manual and investigated techniques was confirmed in all cases with slightly lower results for the nSD approach. Automated techniques resulted in accurate and reproducible evaluation of LV scars from CMR-LGE in ischemic patients with performance similar to the manual technique. Their application could minimize user interaction and computational time, even when compared with semiautomated approaches.

Culture in the Cockpit-CRM in a Multicultural World

NASA Technical Reports Server (NTRS)

Engle, Michael

2000-01-01

Crew Resource Management (CRM) is fundamentally a method for enhancing personal interactions among crewmembers so that safety and efficiency are increased, and at its core involves issues of culture and social interaction. Since CRM is increasingly being adopted by foreign carriers, it is important to evaluate standard CRM techniques from a cultural standpoint, especially if some of these techniques may be enhanced by adapting them to particular cultures. The purpose of this paper is to propose a model for an ideal CRM culture, and to suggest ways that CRM may be adapted to suit particular cultures. The research method was a simple literature search to gather data on CRM techniques and multicultural crews. The results indicate that CRM can be tailored to specific cultures for maximum effectiveness.

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

Lee, Seong-Joo, E-mail: sj.lee@kriss.re.kr; Shim, Jeong Hyun; Kim, Kiwoong

A strong pre-polarization field, usually tenths of a milli-tesla in magnitude, is used to increase the signal-to-noise ratio in ordinary superconducting quantum interference device-based nuclear magnetic resonance/magnetic resonance imaging experiments. Here, we introduce an experimental approach using two techniques to remove the need for the pre-polarization field. A dynamic nuclear polarization (DNP) technique enables us to measure an enhanced resonance signal. In combination with a π/2 pulse to avoid the Bloch-Siegert effect in a micro-tesla field, we obtained an enhanced magnetic resonance image by using DNP technique with a 34.5 μT static external magnetic field without field cycling. In this approach,more » the problems of eddy current and flux trapping in the superconducting pickup coil, both due to the strong pre-polarization field, become negligible.« less

Improvement to the scanning electron microscope image adaptive Canny optimization colorization by pseudo-mapping.

PubMed

Lo, T Y; Sim, K S; Tso, C P; Nia, M E

2014-01-01

An improvement to the previously proposed adaptive Canny optimization technique for scanning electron microscope image colorization is reported. The additional feature, called pseudo-mapping technique, is that the grayscale markings are temporarily mapped to a set of pre-defined pseudo-color map as a mean to instill color information for grayscale colors in chrominance channels. This allows the presence of grayscale markings to be identified; hence optimization colorization of grayscale colors is made possible. This additional feature enhances the flexibility of scanning electron microscope image colorization by providing wider range of possible color enhancement. Furthermore, the nature of this technique also allows users to adjust the luminance intensities of selected region from the original image within certain extent. © 2014 Wiley Periodicals, Inc.

ERTS-1 image enhancement by optically combining density slices

NASA Technical Reports Server (NTRS)

Tapper, G. O.; Pease, R. W.

1973-01-01

The technique of density slicing using a photographic film and its application to enhancement of ERTS-1 imagery has proved to be useful for mapping varigated areal phenomena and provides a useful supplement ot the I2S MiniAddcol viewing system. The intial experiments conducted with this film were encouraging, and indicated that this technique of density slicing using readily accessible darkroom facilities and simple darkroom procedures allows rapid, accurate, and facile interpretation of certain areal phenomena to be made from the imagery. The distribution of the tree yucca, Yucca brevifolia Jaegeriana, in the eastern Mojave Desert of Southern California and southern Nevada was used as an example to test the accuracy of the technique for mapping purposes. The distribution was mapped at a relatively high level of accuracy.

Strategies to enhance waste minimization and energy conservation within organizations: a case study from the UK construction sector.

PubMed

Jones, Jo; Jackson, Janet; Tudor, Terry; Bates, Margaret

2012-09-01

Strategies for enhancing environmental management are a key focus for the government in the UK. Using a manufacturing company from the construction sector as a case study, this paper evaluates selected interventionist techniques, including environmental teams, awareness raising and staff training to improve environmental performance. The study employed a range of methods including questionnaire surveys and audits of energy consumption and generation of waste to examine the outcomes of the selected techniques. The results suggest that initially environmental management was not a focus for either the employees or the company. However, as a result of employing the techniques, the company was able to reduce energy consumption, increase recycling rates and achieve costs savings in excess of £132,000.

Density-controlled, solution-based growth of ZnO nanorod arrays via layer-by-layer polymer thin films for enhanced field emission

NASA Astrophysics Data System (ADS)

Weintraub, Benjamin; Chang, Sehoon; Singamaneni, Srikanth; Han, Won Hee; Choi, Young Jin; Bae, Joonho; Kirkham, Melanie; Tsukruk, Vladimir V.; Deng, Yulin

2008-10-01

A simple, scalable, and cost-effective technique for controlling the growth density of ZnO nanorod arrays based on a layer-by-layer polyelectrolyte polymer film is demonstrated. The ZnO nanorods were synthesized using a low temperature (T = 90 °C), solution-based method. The density-control technique utilizes a polymer thin film pre-coated on the substrate to control the mass transport of the reactant to the substrate. The density-controlled arrays were investigated as potential field emission candidates. The field emission results revealed that an emitter density of 7 nanorods µm-2 and a tapered nanorod morphology generated a high field enhancement factor of 5884. This novel technique shows promise for applications in flat panel display technology.

Comparison of normal and phase stepping shearographic NDE

NASA Astrophysics Data System (ADS)

Andhee, A.; Gryzagoridis, J.; Findeis, D.

2005-05-01

The paper presents results of non-destructive testing of composite main rotor helicopter blade calibration specimens using the laser based optical NDE technique known as Shearography. The tests were performed initially using the already well established near real-time non-destructive technique of Shearography, with the specimens perturbed during testing for a few seconds using the hot air from a domestic hair dryer. Subsequent to modification of the shearing device utilized in the shearographic setup, phase stepping of one of the sheared images to be captured by the CCD camera was enabled and identical tests were performed on the composite main rotor helicopter blade specimens. Considerable enhancement of the images manifesting or depicting the defects on the specimens is noted suggesting that phase stepping is a desirable enhancement technique to the traditional Shearographic setup.

Au nanostructure arrays for plasmonic applications: annealed island films versus nanoimprint lithography

NASA Astrophysics Data System (ADS)

Lopatynskyi, Andrii M.; Lytvyn, Vitalii K.; Nazarenko, Volodymyr I.; Guo, L. Jay; Lucas, Brandon D.; Chegel, Volodymyr I.

2015-03-01

This paper attempts to compare the main features of random and highly ordered gold nanostructure arrays (NSA) prepared by thermally annealed island film and nanoimprint lithography (NIL) techniques, respectively. Each substrate possesses different morphology in terms of plasmonic enhancement. Both methods allow such important features as spectral tuning of plasmon resonance position depending on size and shape of nanostructures; however, the time and cost is quite different. The respective comparison was performed experimentally and theoretically for a number of samples with different geometrical parameters. Spectral characteristics of fabricated NSA exhibited an expressed plasmon peak in the range from 576 to 809 nm for thermally annealed samples and from 606 to 783 nm for samples prepared by NIL. Modelling of the optical response for nanostructures with typical shapes associated with these techniques (parallelepiped for NIL and semi-ellipsoid for annealed island films) was performed using finite-difference time-domain calculations. Mathematical simulations have indicated the dependence of electric field enhancement on the shape and size of the nanoparticles. As an important point, the distribution of electric field at so-called `hot spots' was considered. Parallelepiped-shaped nanoparticles were shown to yield maximal enhancement values by an order of magnitude greater than their semi-ellipsoid-shaped counterparts; however, both nanoparticle shapes have demonstrated comparable effective electrical field enhancement values. Optimized Au nanostructures with equivalent diameters ranging from 85 to 143 nm and height equal to 35 nm were obtained for both techniques, resulting in the largest electrical field enhancement. The application of island film thermal annealing method for nanochips fabrication can be considered as a possible cost-effective platform for various surface-enhanced spectroscopies; while the NIL-fabricated NSA looks like more effective for sensing of small-size objects.

Bas-relief map using texture analysis with application to live enhancement of ultrasound images.

PubMed

Du, Huarui; Ma, Rui; Wang, Xiaoying; Zhang, Jue; Fang, Jing

2015-05-01

For ultrasound imaging, speckle is one of the most important factors in the degradation of contrast resolution because it masks meaningful texture and has the potential to interfere with diagnosis. It is expected that researchers would explore appropriate ways to reduce the speckle noise, to find the edges of structures and enhance weak borders between different organs in ultrasound imaging. Inspired by the principle of differential interference contrast microscopy, a "bas-relief map" is proposed that depicts the texture structure of ultrasound images. Based on a bas-relief map, an adaptive bas-relief filter was developed for ultrafast despeckling. Subsequently, an edge map was introduced to enhance the edges of images in real time. The holistic bas-relief map approach has been used experimentally with synthetic phantoms and digital ultrasound B-scan images of liver, kidney and gallbladder. Based on the visual inspection and the performance metrics of the despeckled images, it was found that the bas-relief map approach is capable of effectively reducing the speckle while significantly enhancing contrast and tissue boundaries for ultrasonic images, and its speckle reduction ability is comparable to that of Kuan, Lee and Frost filters. Meanwhile, the proposed technique could preserve more intra-region details compared with the popular speckle reducing anisotropic diffusion technique and more effectively enhance edges. In addition, the adaptive bas-relief filter was much less time consuming than the Kuan, Lee and Frost filter and speckle reducing anisotropic diffusion techniques. The bas-relief map strategy is effective for speckle reduction and live enhancement of ultrasound images, and can provide a valuable tool for clinical diagnosis. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Mechanistic investigations in sono-hybrid techniques for rice straw pretreatment.

PubMed

Suresh, Kelothu; Ranjan, Amrita; Singh, Shuchi; Moholkar, Vijayanand S

2014-01-01

This paper reports comparative study of two chemical techniques (viz. dilute acid/alkali treatment) and two physical techniques (viz. hot water bath and autoclaving) coupled with sonication, termed as sono-hybrid techniques, for hydrolysis of rice straw. The efficacy of each sono-hybrid technique was assessed on the basis of total sugar and reducing sugar release. The system of biomass pretreatment is revealed to be mass transfer controlled. Higher sugar release is obtained during dilute acid treatment than dilute alkali treatment. Autoclaving alone was found to increase sugar release marginally as compared to hot water bath. Sonication of the biomass solution after autoclaving and stirring resulted in significant rise of sugar release, which is attributed to strong convection generated during sonication that assists effective transport of sugar molecules. Discrimination between individual contributions of ultrasound and cavitation to mass transfer enhancement reveals that contribution of ultrasound (through micro-streaming) is higher. Micro-turbulence as well as acoustic waves generated by cavitation did not contribute much to enhancing of mass transfer in the system. Copyright © 2013 Elsevier B.V. All rights reserved.

Demonstration of vessels in CNS and other organs by AMG silver enhancement of colloidal gold particles dispersed in gelatine.

PubMed

Danscher, G; Andreasen, A

1997-12-01

We present a new autometallographic technique for demonstrating vessels and other small cavities at light microscopy (LM) and electron microscopy (EM) levels. It is possible to obtain detailed knowledge of the 3-D appearance of the vascular system by exchanging blood with a 40 degrees C, 8% gelatine solution containing colloidal gold particles (gold gelatine solution, GGS) and ensuing silver enhancement of the gold particles by autometallography (AMG). The GGS-AMG technique demonstrates the vascular system as a dark web that can be studied in cryostat, vibratome, methacrylate, paraffin and Epon sections at all magnifications. The infused GGS becomes increasingly viscous and finally becomes rigid when the temperature falls below 20 degrees C. An additional advantage of this technique is the fact that none of the tested counterstains or immunotechniques interfere with this AMG approach. The GGS-AMG technique is demonstrated on rat brains but can be applied to any organ. We believe that the present technique is valuable for both experimental studies and routine pathology.

The combined use of order tracking techniques for enhanced Fourier analysis of order components

NASA Astrophysics Data System (ADS)

Wang, K. S.; Heyns, P. S.

2011-04-01

Order tracking is one of the most important vibration analysis techniques for diagnosing faults in rotating machinery. It can be performed in many different ways, each of these with distinct advantages and disadvantages. However, in the end the analyst will often use Fourier analysis to transform the data from a time series to frequency or order spectra. It is therefore surprising that the study of the Fourier analysis of order-tracked systems seems to have been largely ignored in the literature. This paper considers the frequently used Vold-Kalman filter-based order tracking and computed order tracking techniques. The main pros and cons of each technique for Fourier analysis are discussed and the sequential use of Vold-Kalman filtering and computed order tracking is proposed as a novel idea to enhance the results of Fourier analysis for determining the order components. The advantages of the combined use of these order tracking techniques are demonstrated numerically on an SDOF rotor simulation model. Finally, the approach is also demonstrated on experimental data from a real rotating machine.

Influence of forest and rangeland management on anadromous fish habitat in Western North America: rehabilitating and enhancing stream habitat—2. Field applications.

Treesearch

Gordon H. Reeves; Terry D. Roelofs

1982-01-01

Current techniques for rehabilitating and enhancing habitat to increase natural production of anadromous salmonids in the Pacific Northwest and Alaska are described. Methods to enhance spawning, rearing, and riparian habitat, and to improve access are reviewed. The information was compiled from published literature, unpublished reports by State and Federal agencies,...

A Summary of the FHWA Contract Administration Techniques for Quality Enhancement Study Tour (CATQEST)

DOT National Transportation Integrated Search

1994-06-01

There is a widespread impression in the United States that roads and highway structures in Europe are generally superior to comparable facilities in the United States. The joint industry and government project, the Contract Administration Techniques ...

Image Enhancement for Astronomical Scenes

DTIC Science & Technology

2013-09-01

address this problem in the context of natural scenes. However, these techniques often misbehave when confronted with low-SNR scenes that are also...scenes. However, these techniques often misbehave when confronted with low-SNR scenes that are also mostly empty space. We compare two classes of